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We present the fifth edition of the Sloan Digital Sky Survey (SDSS) Quasar Catalog, which is based upon the SDSS Seventh Data Release. The catalog, which contains 105,783 spectroscopically confirmed quasars, represents the conclusion of the SDSS-I and SDSS-II quasar survey. The catalog consists of the SDSS objects that have luminosities larger than M_i = -22.0 (in a cosmology with H_0 = 70 km/s/Mpc Omega_M = 0.3, and Omega_Lambda = 0.7) have at least one emission line with FWHM larger than 1000 km/s or have interesting/complex absorption features, are fainter than i > 15.0 and have highly reliable redshifts. The catalog covers an area of 9380 deg^2. The quasar redshifts range from 0.065 to 5.46, with a median value of 1.49; the catalog includes 1248 quasars at redshifts greater than four, of which 56 are at redshifts greater than five. The catalog contains 9210 quasars with i < 18; slightly over half of the entries have i< 19. For each object the catalog presents positions accurate to better than 0.1" rms per coordinate, five-band (ugriz) CCD-based photometry with typical accuracy of 0.03 mag, and information on the morphology and selection method. The catalog also contains radio, near-infrared, and X-ray emission properties of the quasars, when available, from other large-area surveys. The calibrated digital spectra cover the wavelength region 3800-9200 Ang. at a spectral resolution R = 2000 the spectra can be retrieved from the SDSS public database using the information provided in the catalog. Over 96% of the objects in the catalog were discovered by the SDSS. We also include a supplemental list of an additional 207 quasars with SDSS spectra whose archive photometric information is incomplete., Comment: Accepted, to appear in AJ, 7 figures, electronic version of Table 2 is available, see http://www.sdss.org/dr7/products/value_added/qsocat_dr7.html

This report shows how the study of U.S. history can be enriched by blending geography into the curriculum. Because the fields of history and geography have not been melded together in terms of curricula, often history is not taught in relation to geography and geography has tended to be taught primarily as location/place information. The report summarizes the results of a project designed to address this problem through the development of a high school U.S. history curriculum framework that offers teachers the opportunity to teach a traditional U.S. history course enriched by a consistent injection of the geographical aspects of the interaction of people, events, and ideas. It notes that the elements of the framework serve as suggestions for lessons that are rich in content drawn from both disciplines. The report is divided into four sections: (1) "Foreword"; (2) "Why History and Geography Should Be Taught Together"; (3) "How to Use This Framework"; and (4) "U.S. History and Geography Curriculum Framework" (Period 1. Setting the Stage: Before 1492; Period 2. Discovery and Exploration: 1492 to 1607; Period 3. Colonial Period: 1607 to 1763; Period 4. Revolutionary America: 1763 to 1789; Period 5. Early Republic: 1789 to 1820; Period 6. Economic Growth and Expansion: 1820 to 1861; Period 7. The Union in Crisis: 1861 to 1877; Period 8. Emergence of Modern America: 1877 to 1890; Period 9. Rise of America as World Power and World War I: 1890 to 1920; Period 10. Time between the Wars: 1920 to 1939; Period 11. World War II and American Global Preeminence: 1939 to 1957; Period 12. Technological Advances, Vietnam, and Social Upheaval: 1957 to 1973; Period 13: Cold War Climax and New World Order: 1973 to Present). Related papers are appended. (BT)

We present the fourth edition of the Sloan Digital Sky Survey (SDSS) Quasar Catalog. The catalog contains 77,429 objects; this is an increase of over 30,000 entries since the previous edition. The catalog consists of the objects in the SDSS Fifth Data Release that have luminosities larger than M_i = -22.0 (in a cosmology with H_0 = 70 km/s/Mpc, Omega_M = 0.3, and Omega_Lambda = 0.7) have at least one emission line with FWHM larger than 1000 km/s, or have interesting/complex absorption features, are fainter than i=15.0, and have highly reliable redshifts. The area covered by the catalog is 5740 sq. deg. The quasar redshifts range from 0.08 to 5.41, with a median value of 1.48; the catalog includes 891 quasars at redshifts greater than four, of which 36 are at redshifts greater than five. Approximately half of the catalog quasars have i < 19; nearly all have i < 21. For each object the catalog presents positions accurate to better than 0.2 arcsec. rms per coordinate, five-band (ugriz) CCD-based photometry with typical accuracy of 0.03 mag, and information on the morphology and selection method. The catalog also contains basic radio, near-infrared, and X-ray emission properties of the quasars, when available, from other large-area surveys. The calibrated digital spectra cover the wavelength region 3800--9200A at a spectral resolution of ~2000. The spectra can be retrieved from the public database using the information provided in the catalog. The average SDSS colors of quasars as a function of redshift, derived from the catalog entries, are presented in tabular form. Approximately 96% of the objects in the catalog were discovered by the SDSS., Comment: 37 pages, Accepted for publication in AJ

This paper retraces the early development of the social studies curricular pattern of the 1920s and the subsequent division between social studies advocates, represented by the National Council for the Social Studies, and history-centered supporters, represented largely by the American Historical Association. The document maintains that the historical examination of the disputes over social studies issues sheds a needed perspective on current debates in the field and may help to break the lingering impasse between social studies advocates and history-centered supporters. This essay examines disputes over curricular issues in social studies from the 1910s to the 1960s when the debates over substantive issues begin to stall. The paper advocates an historical examination of the first cycle of social studies debates to reveal a great deal about the nature and practice of the field. Contains 160 references. (EH)

Low dispersion optical spectra have been obtained with the Hobby-Eberly Telescope of 22 very red objects found in early imaging data from the Sloan Digital Sky Survey. The objects are assigned spectral types on the 2MASS system (Kirkpatrick et al. 1999) and are found to range from late M to late L. The red- and near-infrared colors from SDSS and 2MASS correlate closely with each other, and most of the colors are closely related to spectral type in this range; the exception is the (i^* - z^*) color, which appears to be independent of spectral type between about M7 and L4. The spectra suggest that this independence is due to the disappearance of the TiO and VO absorption in the i-band for later spectral types; to the presence of strong Na I and K I absorption in the i-band; and to the gradual disappearance of the 8400 Angstrom absorption of TiO and FeH in the z-band., Comment: 20 pages, 7 figures, accepted by AJ, a version with higher resolution figures can be found at ftp://ftp.astro.psu.edu/pub/dps/hetld.ps

This article tabulates doctoral research activity in social studies education as found in "Dissertation Abstracts" published between 1982 and 1991. In this computer-based search, 499 dissertations were identified using "Dissertation Abstracts OnDisc" which is available on CD-ROM. A variety of descriptors were used, one of the least helpful being "social studies." From the dissertation abstracts of these 499, productivity levels were generated by yearly output, page length, gender, grade/level, terminal degree, graduate institution, research type, and topic. In addition, using data reported on five earlier dissertation overviews, research summaries were compiled for the purpose of comparison with contemporary data. Due to a transition in 1991 through 1993 in how research information was identified and categorized, the study was limited to the years 1982-1991. The primary problems of incomplete data due to the information escaping notice or the focus of the research not being clearly related to social studies based on the title alone is recognized. This study does not set out to cut any new intellectual ground, nor interpret, classify or evaluate dissertation work in social studies. The report offers general descriptive information on dissertation research. These data may be useful to graduate students in social studies, theses supervisors, and those interested in general trends in social studies dissertation research. (EH)

We report the discovery of a pair of z = 4.25 quasars with a separation of 33 arcseconds. The brighter of the two objects was identified as a high-redshift quasar candidate from Sloan Digital Sky Survey multicolor imaging data, and the redshift was measured from a spectrum obtained with the Hobby-Eberly Telescope. The slit orientation of this observation {\it by chance} included another quasar, approximately one magnitude fainter and having the same redshift as the target. This is the third serendipitous discovery of a z > 4 quasar. The differences in the relative strengths and profiles of the emission lines suggest that this is a quasar pair and not a gravitational lens. The two objects are likely to be physically associated; the projected physical separation is approximately 210 $h_{50}^{-1}$ kpc and the redshifts are identical to $\approx$ 0.01, implying a radial physical separation of 950 $h_{50}^{-1}$ kpc or less. The existence of this pair is strong circumstantial evidence that $z \sim 4$ quasars are clustered., Comment: 15 pages, 4 figures, submitted to AJ

Observations with the Wide-Field Camera of the Hubble Space Telescope are presented for a representative sample of 20 intrinsically luminous quasars with redshifts smaller than 0.30. These observations show that luminous quasars occur in diverse environments that include ellipticals as bright as the brightest cluster galaxies (2), apparently normal ellipticals (10), apparently normal spirals with H II regions (3), complex systems of gravitationally interacting components (3), and faint surrounding nebulosity (2). The quasar host galaxies are centered on the quasar to the accuracy of our measurements, 0.4 kpc. There are more radio quiet quasars in galaxies that appear to be ellipticals (7) than in spiral hosts (3), contrary to expectations. The average luminosity of the hosts is 2.2 magnitudes brighter than expected for a field galaxy luminosity function. We detect eight companion galaxies within projected distances of 10 kpc from quasar nuclei. Best figs. at http://www.sns.ias.edu/~jnb/Html/preprints.html, Comment: LaTeX file, 47 pages + 8 figures. Accepted for publication in The Astrophysical Journal. Revised references

A novel use of periodic functions, called the periodic procedure, was recently introduced to make practical the use of certain physical measurement ideas in psychology. This paper reports a successful attempt to apply the periodic procedure to an important psychological measurement problem, the measurement of aptitude test item difficulties. The difficulties of items on a subtest of the Scholastic Aptitude Test were measured with both the periodic procedure and with an item characteristic curve theory procedure. The principal finding was a close agreement between the two methods. This close agreement was particularly striking because different samples (from the same test administration) were used by the two methods. The statistical development of the periodic procedure is presented along with an example of its use. (Author/JKS)

Claims that the proposed National History Standards subvert the legitimate purpose of history instruction, the explanation and understanding of historical meaning, in an effort to redress historical grievances. Argues that the Standards apply a critical perspective to European culture while celebrating the achievements of native cultures. (MJP)

Asserts that social studies or history methods textbooks do not enjoy the same popularity among teachers they once did. Reviews five texts used prior to 1910 and maintains that each contributed to the traditional history curriculum. (CFR)

Addresses the difficulty of teaching historical perspective to students. Suggests that teachers can teach historical concepts better by trying to understand how to use indefinite time expressions. Presents results of a study focusing on teacher perceptions of student responses to indefinite time expressions. Discusses the building of time lines to aid student understanding. (DK)

We present the observational and data processing aspects of the Hubble Space Telescope Quasar Absorption Line Key Project. Topics discussed include the observational technique, calibration of the data, software that simulates the data, the automated procedure used to identify and characterize the absorption features, and the determination of the sensitivity limits of the survey.

Finding charts and J2000 positions accurate to about 1 arcsec are presented for the 528 high-redshift (z is greater than 1), luminous (MV is less than -25.5) quasars investigated in the HST Snapshot Survey. A histogram showing the distribution of the differences between the positions determined by the Space Telescope Science Institute Astrometric Support Program and the catalog positions is provided.