Prepped for Success? Supporting Pregnant and Parenting Teens in Chicago Schools

In 2000, there were 8,153 births to mothers under the age of 20 in the city of Chicago. Forty-one percent of those births (3321) were to teenagers 17 or younger. Research has demonstrated that teen mothers are more likely than other teens to drop out of school and become dependent on welfare. 2 When a teen mother does not finish high school, she is more likely to become trapped in poverty than her better-educated peers. With so many potential negative effects of poverty on the teen and on her child, it is critically important to help the teen mother finish her education while she is still young and more likely to finish.During the course of its work on issues around pregnant and parenting teens, the Center for Impact Research (CIR) has heard from several advocates and service providers about the barriers teen parents face in furthering their education. 3 In addition to helping pregnant and parenting teens prepare for their new parental roles, many teen service providers help young parents navigate through various institutional systems. Some of these service providers reported negative impressions about how various educational systems in Chicago deal with pregnant and parenting teens. Service providers believed that some Chicago Public Schools teachers and administrators were not addressing the needs of pregnant and parenting teens and were inappropriately pushing them out of CPS schools and referring them elsewhere

Young Low-Mass Stars and Brown Dwarfs in IC 348

I present new results from a continuing program to identify and characterize the low-mass stellar and substellar populations in the young cluster IC 348 (1-10~Myr). Optical spectroscopy has revealed young objects with spectral types as late as M8.25. The intrinsic J-H and H-K colors of these sources are dwarf-like, whereas the R-I and I-J colors appear intermediate between the colors of dwarfs and giants. Furthermore, the spectra from 6500 to 9500 A are reproduced well with averages of standard dwarf and giant spectra, suggesting that such averages should be used in the classification of young late-type sources. An H-R diagram is constructed for the low-mass population in IC 348 (K6-M8). The presumably coeval components of the young quadruple system GG~Tau (White et al.) and the locus of stars in IC 348 are used as empirical isochrones to test the theoretical evolutionary models. For the models of Baraffe et al., an adjustment of the temperature scale to progressively warmer temperatures at later M types, intermediate between dwarfs and giants, brings all components of GG~Tau onto the same model isochrone and gives the population of IC 348 a constant age and age spread as a function of mass. When other observational constraints are considered, such as the dynamical masses of GM~Aur, DM~Tau, and GG~Tau~A, the models of Baraffe et al. are the most consistent with observations of young systems. With compatible temperature scales, the models of both D'Antona & Mazzitelli and Baraffe et al. suggest that the hydrogen burning mass limit occurs near M6 at ages of <10 Myr. Thus, several likely brown dwarfs are discovered in this study of IC 348, with masses down to ~20-30 M_J.Comment: 23 pages, 9 figures, accepted to Ap

Multiprocessor task scheduling in multistage hyrid flowshops: a genetic algorithm approach

This paper considers multiprocessor task scheduling in a multistage hybrid flow-shop environment. The objective is to minimize the make-span, that is, the completion time of all the tasks in the last stage. This problem is of practical interest in the textile and process industries. A genetic algorithm (GA) is developed to solve the problem. The GA is tested against a lower bound from the literature as well as against heuristic rules on a test bed comprising 400 problems with up to 100 jobs, 10 stages, and with up to five processors on each stage. For small problems, solutions found by the GA are compared to optimal solutions, which are obtained by total enumeration. For larger problems, optimum solutions are estimated by a statistical prediction technique. Computational results show that the GA is both effective and efficient for the current problem. Test problems are provided in a web site at www.benchmark.ibu.edu.tr/mpt-h; fsp

Towards an integrated scientific and social case for human space exploration

I will argue that an ambitious programme of human space exploration, involving a return to the Moon, and eventually human missions to Mars, will add greatly to human knowledge. Gathering such knowledge is the primary aim of science, but science's compart-mentalisation into isolated academic disciplines tends to obscure the overall strength of the scientific case. Any consideration of the scientific arguments for human space exploration must therefore take a holistic view, and integrate the potential benefits over the entire spectrum of human knowledge. Moreover, science is only one thread in a much larger overall case for human space exploration. Other threads include economic, industrial, educational, geopolitical and cultural benefits. Any responsibly formulated public space policy must weigh all of these factors before deciding whether or not an investment in human space activities is scientifically and socially desirable

Collective Action and Responses to Poor‐Quality Recycling in St. John’s

This paper discusses the lack of proper recycling programs in St John’s, NL and explains the relevance of collective action and rational choice theories in addressing the matter. The city has done a poor job of implementing proper recycling programs, and is one of only two provincial capitals that does not offer a government-funded curb‐side recycling program. While some private recycling programs do exist in the city, they are inefficient and thus viewed by the populace as a waste of time. As most people believe that their individual waste contributions will not make much difference to the overall state of the environment, waste continues to accumulate and negatively impact the environment, as well as the image and state of the city. Collective action theory, as discussed by Ostrom, offers several possible solutions, such as privatization of territory or discussion amongst the populace. Unfortunately, such solutions are impractical for this particular problem. The government must step in and impose a recycling “Leviathan” by implementing mandatory recycling and forcing citizens to recycle or be left with their own refuse. Only by making recycling a self-interested priority for the populace will St John’s be able to improve its waste management practices

Determination of the urinary aglycone metabolites of vitamin K by HPLC with redox-mode electrochemical detection

We describe a method for the determination of the two major urinary metabolites of vitamin K as the methyl esters of their agyclone structures, 2-methyl-3-(3-3-carboxymethylpropyl)-1,4-naphthoquinone (5C-side-chain metabolite) and 2-methyl-3-(5-carboxy-3-methyl-2-pentenyl)-1,4-naphthoquinone (7C-side-chain metabolite), by HPLC with electrochemical detection (ECD) in the redox mode. Urinary salts were removed by reversed-phase (C18) solid phase extraction (SPE) and the predominately conjugated vitamin K metabolites hydrolysed with methanolic HCl. The resultant carboxylic acid aglycones were quantitatively methylated with diazomethane and fractionated by normal-phase (silica) SPE. Final analysis was by reversed-phase (C18) HPLC with a methanol-aqueous mobile phase. Metabolites were detected by amperometric, oxidative ECD of their quinol forms, which were generated by post-column coulometric reduction at an upstream electrode. The assay gave excellent linearity (r2 typically = 0.999) and high sensitivity with an on-column detection limit of <3.5 fmol (<1pg). The inter-assay precision was typically 10%. Metabolite recovery was compared to that of an internal standard (2-methyl-3-(7'-carboxy-heptyl)-1,4-naphthoquinone), added to urine samples just before analysis. Using this methodology we confirmed that the 5C- and 7C-metabolite were major catabolites of both phylloquinone (vitamin K1) and menaquinones (vitamin K2) in humans. We propose that the measurement of urinary vitamin K metabolite excretion is a candidate non-invasive marker of total vitamin K status

Silicon Micromachined Packages for RF MEMS Switches

MEMS technology has major applica-tions in developing smaller, faster and less energy consuming devices provided that reliability of pack-aging/ interconnect technology is sufficiently addressed. This paper presents a low cost, on-wafer, silicon mi-cromachined packaging scheme for RF MEMS switches having excellent electrical performance in K-band. In particular, the package demonstrates an insertion loss of 0.1dB and a return loss of 32dB at 20 GHz. The package is fabricated in parallel with the MEMS switch on the same wafer and therefore requires no lossy solder bumps or bond wires to achieve signal propagation

A Census of the Young Cluster IC 348

We present a new census of the stellar and substellar members of the young cluster IC 348. We have obtained images at I and Z for a 42'x28' field encompassing the cluster and have combined these measurements with previous optical and near-infrared photometry. From spectroscopy of candidate cluster members appearing in these data, we have identified 122 new members, 15 of which have spectral types of M6.5-M9, corresponding to masses of 0.08-0.015 M_sun by recent evolutionary models. The latest census for IC 348 now contains a total of 288 members, 23 of which are later than M6 and thus are likely to be brown dwarfs. From an extinction-limited sample of members (A_V<=4) for a 16'x14' field centered on the cluster, we construct an IMF that is unbiased in mass and nearly complete for M/M_sun>=0.03 (<=M8). In logarithmic units where the Salpeter slope is 1.35, the mass function for IC 348 rises from high masses down to a solar mass, rises more slowly down to a maximum at 0.1-0.2 M_sun, and then declines into the substellar regime. In comparison, the similarly-derived IMF for Taurus from Briceno et al. and Luhman et al. rises quickly to a peak near 0.8 M_sun and steadily declines to lower masses. The distinctive shapes of the IMFs in IC 348 and Taurus are reflected in the distributions of spectral types, which peak at M5 and K7, respectively. These data provide compelling, model-independent evidence for a significant variation of the IMF with star-forming conditions.Comment: 47 pages, 14 figures, 3rd para of 4.5.3 has been added, this is final version in press at ApJ, also found at http://cfa-www.harvard.edu/sfgroup/preprints.htm

A Flaring Megamaser in Mrk 348

We report new observations of the H2O megamaser in the Seyfert 2 galaxy Mrk 348. Following our initial detection in 2000 March using the Effelsberg 100 m telescope, re-analysis of previous data on this source indicates that the maser was present but only marginally detectable in late 1997. Monitoring through late 2000 shows that the maser has again decreased to its original level. The H2O line is redshifted by ~130 km/s with respect to the systemic velocity, is extremely broad, with a FWHM of 130 km/s, and has no detectable high velocity components within 1500 km/s on either side of the strong line. Followup VLBA observations show that the maser emission emanates entirely from a region >0.25 pc in extent, toward the base of the radio jet.Comment: 4 pages, 2 figures, to appear in Cosmic Masers: from Protostars to Black Holes, IAU 206, Eds. V. Migenes et al., ASP Conference Serie