Alone: A Widow\u27s Search for Joy (Book Review)

Reviewed Title: Alone: A Widow\u27s Search for Joy, by Katie E. Wiebe, Tyndale House Publishers, Inc., Wheaton, Illinois, 1976, 303 pages

All Hallows\u27 Eve (Book Review)

Reviewed Title: All Hallows\u27 Eve by Charles Williams, Grand Rapids, Michigan: William B. Eerdmans Publishing Company, 1981, a reprint of the 1948 edition. 274 pages

Faith and Victory in Dachau (Book Review)

Reviewed Title: Faith and Victory in Dachau, by Rev. Jack Overduin, translated by Harry der Nederlanden, Paideia Press, 1978, 252 pages

Captured (Book Review)

Reviewed Title: Captured, by Carolyn Paine Miller, Christian Herald Books, Chappaqua, New York, 288 pages

Data report: high-resolution mineralogy for leg 199 based on reflectance spectroscopy and physical properties

Journal ArticleDuring Ocean Drilling Program Leg 199 in the equatorial Pacific, visible and near-infrared spectroscopy (VNIS) was used to measure the reflectance spectra (350?2500 nm) of 1343 sediment samples. Reflectance spectra were also measured for a suite of 60 samples of known mineralogy, thereby providing a local ground-truth calibration of spectral features to percentages of calcite, opal, smectite, and illite. The associated algorithm was used to calculate mineral percentages from the 1343 spectra. Using multiple regression and VNIS mineralogy, multisensor track physical properties and light spectroscopy data were then converted into continuous high-resolution mineralogy logs

Global metallicity of globular cluster stars from colour-magnitude diagrams

We have developed an homogeneous evolutionary scenario for H- and He-burning low-mass stars by computing updated stellar models for a wide metallicity and age range (0.0002$\le Z \le$0.004 and 9$\le t(Gyr) \le$15, respectively) suitable to study globular clusters. This theoretical scenario allows us to provide self-consistent predictions about the dependence of selected observational features of the colour-magnitude diagram, such as the brightness of the Turn Off (TO), Zero Age Horizontal Branch (ZAHB) and Red Giant Branch bump (BUMP), on the cluster metallicity and age. Taking into account these predictions, we introduce a new observable based on the visual magnitude difference between the TO and the ZAHB, and the TO and the RGB-bump, given by $A=\Delta M_V$(TO-BUMP)$-0.566\Delta M_V$(TO-ZAHB). We show that the parameter $A$ does not depend at all on the cluster age, whereas it does strongly depend on the cluster global metallicity. The calibration of the parameter $A$ as a function of $Z$ is then provided, as based on our evolutionary models. We tested the reliability of this result by also considering stellar models computed by other authors,employing different input physics. Eventually, we present clear evidence that the variation of $\Delta M_V$(TO-BUMP) with $\Delta M_V$(TO-ZAHB) does supply a powerful probe of the global metal abundance, at least when homogeneous theoretical frameworks are adopted. We provide an estimate of the global metallicity of 36 globular clusters in the Milky Way, based on our {\it A-Z} calibration, and a large observational database of Galactic GCs. By considering the empirical [Fe/H] scales by both Zinn & West (1984) and Carretta & Gratton (1997), we are also able to provide an estimate of the GC $\alpha-$element enhancement.Comment: 10 pages, 10 figures, in press on MNRA

Eocene biogenic silica accumulation rates at the Pacific equatorial divergence zone

Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/94733/1/palo1454.pd

Stars of extragalactic origin in the solar neighborhood

We computed the spatial velocities and the galactic orbital elements using Hipparcos data for 77 nearest main-sequence F-G-stars with published the iron, magnesium, and europium abundances determined from high dispersion spectra and with the ages estimated from theoretical isochrones. A comparison with the orbital elements of the globular clusters that are known was accreted by our Galaxy in the past reveals stars of extragalactic origin. We show that the relative elemental abundance ratios of r- and \alpha- elements in all the accreted stars differ sharply from those in the stars that are genetically associated with the Galaxy. According to current theoretical models, europium is produced mainly in low mass Type II supernovae (SNe II), while magnesium is synthesized in larger amounts in high mass SN II progenitors. Since all the old accreted stars of our sample exhibit a significant Eu overabundance relative to Mg, we conclude that the maximum masses of the SNII progenitors outside the Galaxy were much lower than those inside it are. On the other hand, only a small number of young accreted stars exhibit low negative ratios $[Eu/Mg] < 0$. The delay of primordial star formation burst and the explosions of high mass SNe II in a relatively small part of extragalactic space can explain this situation. We provide evidence that the interstellar medium was weakly mixed at the early evolutionary stages of the Galaxy formed from a single proto-galactic cloud and that the maximum mass of the SN II progenitors increased in it with time simultaneously with the increase in mean metallicity.Comment: Accepted for 2004, Astronomy Letters, Vol. 30, No. 3, P.148-158 15 pages, 3 figure