Abstinence-Only Until Marriage and Abstinence Pledge Programs: A Policy Review for Stakeholders

Sexually transmitted infections (STIs) and unplanned pregnancy are significant public health concerns. Abstinence-only until marriage (AOUM) and abstinence pledge programs have received a significant amount of government funding in an attempt to address these problems. Despite receiving over two billion dollars in funding, the programs have not been shown to be effective in achieving their stated goals. In addition, there are significant concerns about the content of AOUM curriculums, including medical inaccuracy and use of outdated gender stereotypes

Role of phi decays for K- yields in relativistic heavy-ion collisions

The production of strange mesons in collisions of Ar+KCl at a kinetic beam energy of 1.756 AGeV is studied within a transport model of Boltzmann-\"Uhling-Uhlenbeck (BUU) type. In particular, $\phi, K^+$ and $K^-$ yields and spectra are compared to the data mesured recently by the HADES collaboration and the $\phi$ yield measured previously by the FOPI collaboration. Our results are in agreement with these data thus presenting an interpretation of the subleading role of $\phi$ decays into $K^-$'s and confirming the importance of the strangeness-exchange channels for $K^-$ production.Comment: 24 pages, 19 figure

Phase diagram and optical conductivity of La1.8-xEu0.2SrxCuO4

La1.8-xEu0.2SrxCuO4 (LESCO) is the member of the 214 family which exhibits the largest intervals among the structural, charge ordering (CO), magnetic, and superconducting transition temperatures. By using new dc transport measurements and data in the literature we construct the phase diagram of LESCO between x = 0.8 and 0.20. This phase diagram has been further probed in ac, by measuring the optical conductivity {\sigma}1({\omega}) of three single crystals with x = 0.11, 0.125, and 0.16 between 10 and 300 K in order to associate the extra-Drude peaks often observed in the 214 family with a given phase. The far-infrared peak we detect in underdoped LESCO is the hardest among them, survives up to room temperature and is associated with charge localization rather than with ordering. At the CO transition for the commensurate doping x = 0.125 instead the extra-Drude peak hardens and a pseudogap opens in {\sigma}1({\omega}), approximately as wide as the maximum superconducting gap of LSCO.Comment: 6 pages, 6 figure

Effects of Superconductivity and Charge Order on the sub-Terahertz reflectivity of La1.875_{1.875}Ba0.125−y_{0.125-y}Sry_{y}CuO4_4

The reflectivity $R (\omega)$ of both the $ab$ plane and the c axis of two single crystals of La$_{1.875}$Ba$_{0.125-y}$Sr$_{y}$CuO$_4$ has been measured down to 5 cm$^{-1}$, using coherent synchrotron radiation below 30 cm$^{-1}$. For $y$ = 0.085, a Josephson Plasma Resonance is detected at $T \ll T_c$ = 31 K in $R_{c} (\omega)$, and a far-infrared peak (FIP) appears in the optical conductivity below 50 K, where non-static charge ordering (CO) is reported by X-ray scattering. For $y$ = 0.05 ($T_c$ = 10 K), a FIP is observed in the low-temperature tetragonal phase below the ordering temperature $T_{CO}$. At 1/8 doping the peak frequency scales linearly with $T_{CO}$, confirming that the FIP is an infrared signature of CO, either static or fluctuating.Comment: v2: longer version, 9 pages, 6 color figure

Evolution of Cluster Ellipticals at 0.2 < z < 1.2 from Hubble Space Telescope Imaging

Two-dimensional surface photometry derived from Hubble Space Telescope imaging is presented for a sample of 225 early-type galaxies (assumed to be cluster members) in the fields of 9 clusters at redshifts $0.17 < z < 1.21$. The 94 luminous ellipticals ($M_{AB}(B)<-20$; selected by morphology alone with no reference to color) form tight sequences in the size-luminosity plane. The position of these sequences shifts, on average, with redshift so that an object of a given size at z=0.55 is brighter by $\Delta M(B)=-0.57 \pm 0.13$ mag than its counterpart (measured with the same techniques) in nearby clusters. At z=0.9 the shift is $\Delta M(B)=-0.96 \pm 0.22$ mag. If the relation between size and luminosity is universal so that the local cluster galaxies represent the evolutionary endpoints of those at high redshift, and if the size-luminosity relation is not modified by dynamical processes then this population of galaxies has undergone significant luminosity evolution since z=1 consistent with expectations based on models of passively evolving, old stellar populations.Comment: 7 pages, 3 figures, and 1 Tabl

The Impact of Visual Impairment on Perceived School Climate

The current investigation examines whether visual impairment has an impact on a student’s perception of the school climate. Using a large national sample of high school students, perceptions were examined for students with vision impairment relative to students with no visual impairments. Three factors were examined: self-reported level of happiness, perception of a positive school climate, and negative school affect.  Results revealed no differences for the seeing and visually impaired students on self-reported happiness and perception of a positive school climate factors, however significant differences were found on the negative school affect factor. Additionally, gender was significantly related to the negative school affect factor

Atmospheric methanol measurement using selective catalytic methanol to formaldehyde conversion

International audienceA novel atmospheric methanol measurement technique, employing selective gas-phase catalytic conversion of methanol to formaldehyde followed by detection of the formaldehyde product, has been developed and tested. The effects of temperature, gas flow rate, gas composition, reactor-bed length, and reactor-bed composition on the methanol conversion efficiency of a molybdenum-rich, iron-molybdate catalyst [Mo-Fe-O] were studied. Best results were achieved using a 1:4 mixture (w/w) of the catalyst in quartz sand. Optimal methanol to formaldehyde conversion (>95% efficiency) occurred at a catalyst housing temperature of 345°C and an estimated sample-air/catalyst contact time of <0.2 seconds. Potential interferences arising from conversion of methane and a number of common volatile organic compounds (VOC) to formaldehyde were found to be negligible under most atmospheric conditions and catalyst housing temperatures. Using the new technique, atmospheric measurements of methanol were made at the University of Bremen campus from 1 to 15 July 2004. Methanol mixing ratios ranged from 1 to 5 ppb with distinct maxima at night. Formaldehyde mixing ratios, obtained in conjunction with methanol by periodically bypassing the catalytic converter, ranged from 0.2 to 1.6 ppb with maxima during midday. These results suggest that selective, catalytic methanol to formaldehyde conversion, coupled with existing formaldehyde measurement instrumentation, is an inexpensive and effective means for monitoring atmospheric methanol

Observation of charge-density-wave excitations in manganites

In the optical conductivity of four different manganites with commensurate charge order (CO), strong peaks appear in the meV range below the ordering temperature T_{CO}. They are similar to those reported for one-dimensional charge density waves (CDW) and are assigned to pinned phasons. The peaks and their overtones allow one to obtain, for La{1-n/8}Ca{n/8}$MnO{3} with n = 5, 6, the electron-phonon coupling, the effective mass of the CO system, and its contribution to the dielectric constant. These results support a description of the CO in La-Ca manganites in terms of moderately weak-coupling and of the CDW theory.Comment: To be published on Phys. Rev. Let

INTERACTION BETWEEN THE POLE AND THE HUMAN BODY AND ITS EFFECT ON THE POLE VAULTING PERFORMANCE

The purposes of this study were: (a) to examine the utilization of pole elasticity by the athletes through muscular work and to develope performance criteria throughout the pole vault and (b) to examine the reproducibility and the athlete's specificity of the developed criteria. In the study, 6 athletes performed from 4 to 11 trials each, at 90% of their respective personal best performance. All trials were recorded using four synchronized, genlocked video cameras operating at 50 Hz. The ground reaction forces exerted on the bottom of the pole were measured using a planting box fixed on a kistler force plate (1000 Hz). The interaction between athlete and pole may be split into two parts. During the first part of the interaction, energy is transferred into the pole and the total energy of the athlete decreases. The difference between the energy decrease of the athlete and the pole energy indicates if the athletes are producing additional energy by means of muscular work (criterion 1). In the second part of the interaction, energy is transferred back to the athlete and the total energy of the athlete increases. The difference between the returned pole energy and the amount of energy increase of the athlete defines criterion 2. The criteria are reproducible, specific to each athlete, capable of identifying deficits or strengths of the athlete's performance during his interaction with the pole; they can therefore estimate the quality of the technique during each of the phases of the interaction athlete-pole

Infrared study of the charge-ordered multiferroic LuFe(2)O(4)

The reflectivity of a large LuFe(2)O(4) single crystal has been measured with the radiation field either perpendicular or parallel to the c axis of its rhombohedral structure, from 10 to 500K, and from 7 to 16000 cm-1. The transition between the two-dimensional and the three-dimensional charge order at T_(CO) = 320 K is found to change dramatically the phonon spectrum in both polarizations. The number of the observed modes above and below T_(CO), according to a factor-group analysis, is in good agreement with a transition from the rhombohedral space group R{bar 3}m to the monoclinic C2/m. In the sub-THz region a peak becomes evident at low temperature, whose origin is discussed in relation with previous experiments.Comment: Physical Review B in pres