Beyond \u3ci\u3eBaby M\u3ci\u3e: International Perspectives on Gestational Surrogacy and the Demise of the Unitary Biological Mother

Gestational surrogacy raises a host of legal and ethical issues. A review of state, federal, and international response, both legislative and judicial, to these issues reveals that the United States would benefit from comprehensive federal legislation regulating the reproductive technology field

LDR segmented mirror technology assessment study

In the mid-1990s, NASA plans to orbit a giant telescope, whose aperture may be as great as 30 meters, for infrared and sub-millimeter astronomy. Its primary mirror will be deployed or assembled in orbit from a mosaic of possibly hundreds of mirror segments. Each segment must be shaped to precise curvature tolerances so that diffraction-limited performance will be achieved at 30 micron (nominal operating wavelength). All panels must lie within 1 micron on a theoretical surface described by the optical precipitation of the telescope's primary mirror. To attain diffraction-limited performance, the issues of alignment and/or position sensing, position control of micron tolerances, and structural, thermal, and mechanical considerations for stowing, deploying, and erecting the reflector must be resolved. Radius of curvature precision influences panel size, shape, material, and type of construction. Two superior material choices emerged: fused quartz (sufficiently homogeneous with respect to thermal expansivity to permit a thin shell substrate to be drape molded between graphite dies to a precise enough off-axis asphere for optical finishing on the as-received a segment) and a Pyrex or Duran (less expensive than quartz and formable at lower temperatures). The optimal reflector panel size is between 1-1/2 and 2 meters. Making one, two-meter mirror every two weeks requires new approaches to manufacturing off-axis parabolic or aspheric segments (drape molding on precision dies and subsequent finishing on a nonrotationally symmetric dependent machine). Proof-of-concept developmental programs were identified to prove the feasibility of the materials and manufacturing ideas

Study of the energy resolution in the electromagnetic end-caps of the future LDC detector for the ILC

The electromagnetic end-caps of the future LDC detector for the ILC ("International Linear Collider") have been simulated with the MOKKA software. The goal of this study is to determine the energy resolution with the classical method, i.e. the energy deposited in 30 + 10 active silicon layers, preceded by 1.4 and 4.2 mm of tungsten placed perpendicularly to the beam axis, respectively. The energy resolution has been fitted by the function $\Delta E/E = a/\sqrt {E} c$ and it was found that a = 12.69 +- 0.17 % GeV$^{1/2}$ and c = 0.839 +- 0.026 % for incident electrons at $\theta$=21.80 degrees and a = 13.33 +- 0.24 % GeV$^{1/2}$ and c = 0.968 +- 0.050 % for incident photons with the same polar angle

Severe Physical Intimate Partner Violence and the Mental and Physical Health of U.S. Caribbean Black Women

Background: Intimate partner violence is a threat to women's health. Relative to other racial/ethnic groups, African American and immigrant women are at an increased risk for violence. However, despite the growing presence of Caribbean Black immigrants in this country, few studies have examined the association between severe physical intimate partner violence (SPIPV) and the health of Caribbean Black women currently residing in the United States. This study examined the mental and physical health of U.S. Caribbean Black women with and without a history of SPIPV. We also explored the role of generational status?first, second, or third?in association with the physical and mental health of abused Caribbean Black women. Methods: Data from the National Survey of American Life, the largest and the only known representative study on Caribbeans residing in the United States, were analyzed. The World Health Organization (WHO) World Mental Health Composite International Diagnostic Interview (WMH-CIDI) was used to determine DSM-IV mental disorders. The presence of physical health conditions was based on respondents' self-reports of physician diagnoses. Results: The findings indicate an association between SPIPV and the mental and physical health status of U.S. Caribbean Black women. Rates of physical conditions and mental health disorders were generally higher among women with a history of SPIPV than those without a history. Generational status also played a role in women's health outcomes. Conclusions: The study has interventions and preventive implications for both detecting and addressing the health needs of U.S. Caribbean Black women who experience severe physical abuse by an intimate partner.Peer Reviewedhttps://deepblue.lib.umich.edu/bitstream/2027.42/140138/1/jwh.2015.5293.pd

Sex steroid dynamics during embryogenesis and sexual differentiation in Eurasian perch, Perca fluviatilis

It is widely accepted that sex steroid hormones play an important and a specific role during the process of sex differentiation in fish. In order to describe the role of the three main sex steroid hormones (testosterone--T, 17beta-estradiol--E2 and 11keto-testosterone--11KT) during embryogenesis and sex differentiation in Eurasian perch, Perca fluviatilis, eggs, larvae and juveniles originating from two mixed-sex and two all-female progenies were regularly sampled from fertilization to hatching (D0) and from hatching to day 70 post-hatching (D70). Just after spawning, a significant amount of sex steroids [T (1634.2pgg(-1)), E2 (554.4pgg(-1)) and 11KT (1513.2pgg(-1))] was measured in non-fertilised eggs suggesting a maternal transmission of these steroids. From D2 to D70 post-hatching, E2 levels were significantly higher in mixed-sex progenies (median: 725.7pgg(-1)) than in all-female progenies (156.2pgg(-1)) and significantly increased after the onset of the histological differentiation of the gonad in both progenies (D35). Levels of 11KT were significantly higher in mixed-sex (median: 431.5pgg(-1)) than in all-female progenies (below the limit of assay detection) and significantly increased at D35 in all-female progenies (median value: 343.2pgg(-1)). Mean 11KT to E2 ratio was six-fold higher in mixed-sex progenies (1.35) than in all-female progenies (0.24). The data suggest that the 11-oxygenated androgen (11KT) plays a major role in the male differentiation process, and that sex differentiation in Eurasian perch is probably determined by the 11KT to E2 ratio

Breakdown of a conservation law in incommensurate systems

We show that invariance properties of the Lagrangian of an incommensurate system, as described by the Frenkel Kontorova model, imply the existence of a generalized angular momentum which is an integral of motion if the system remains floating. The behavior of this quantity can therefore monitor the character of the system as floating (when it is conserved) or locked (when it is not). We find that, during the dynamics, the non-linear couplings of our model cause parametric phonon excitations which lead to the appearance of Umklapp terms and to a sudden deviation of the generalized momentum from a constant value, signalling a dynamical transition from a floating to a pinned state. We point out that this transition is related but does not coincide with the onset of sliding friction which can take place when the system is still floating.Comment: 7 pages, 6 figures, typed with RevTex, submitted to Phys. Rev. E Replaced 27-03-2001: changes to text, minor revision of figure

Particle currents and the distribution of terrace sizes in unstable epitaxial growth

A solid-on-solid model of epitaxial growth in 1+1 dimensions is investigated in which slope dependent upward and downward particle currents compete on the surface. The microscopic mechanisms which give rise to these currents are the smoothening incorporation of particles upon deposition and an Ehrlich-Schwoebel barrier which hinders inter-layer transport at step edges. We calculate the distribution of terrace sizes and the resulting currents on a stepped surface with a given inclination angle. The cancellation of the competing effects leads to the selection of a stable magic slope. Simulation results are in very good agreement with the theoretical findings.Comment: 4 pages, including 3 figure