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We demonstrate Ramsey-Bord\'e (RB) atom interferometry for high performance laser stabilization with fractional frequency instability $<2 \times 10^{-16}$ for timescales between 10 and 1000s. The RB spectroscopy laser interrogates two counterpropagating $^{40}$Ca beams on the $^1$S$_0$ -- $^3$P$_1$ transition at 657 nm, yielding 1.6 kHz linewidth interference fringes. Fluorescence detection of the excited state population is performed on the (4s4p) $^3$P$_1$ -- (4p$^2$) $^3$P$_0$ transition at 431 nm. Minimal thermal shielding and no vibration isolation are used. These stability results surpass performance from other thermal atomic or molecular systems by one to two orders of magnitude, and further improvements look feasible.

Supercontinuum generation using chip-integrated photonic waveguides is a powerful approach for spectrally broadening pulsed laser sources with very low pulse energies and compact form factors. When pumped with a mode-locked laser frequency comb, these waveguides can coherently expand the comb spectrum to more than an octave in bandwidth to enable self-referenced stabilization. However, for applications in frequency metrology and precision spectroscopy, it is desirable to not only support self-referencing, but also to generate low-noise combs with customizable broadband spectra. In this work, we demonstrate dispersion-engineered waveguides based on silicon nitride that are designed to meet these goals and enable precision optical metrology experiments across large wavelength spans. We perform a clock comparison measurement and report a clock-limited relative frequency instability of $3.8\times10^{-15}$ at $\tau = 2$ seconds between a 1550 nm cavity-stabilized reference laser and NIST's calcium atomic clock laser at 657 nm using a two-octave waveguide-supercontinuum comb.

Factors that contribute to the temperature dependence of a resonant frequency in a low-expansion optical cavity are discussed, including deformation at the cavity ends due to different coefficients of thermal expansion (CTE) of the spacer, optically-contacted mirror substrate and coating. A model of the temperature dependence is presented that incorporates finite-element-analysis of the cavity ends. A measurement of frequency versus temperature of a cavity mode is used along with the model to deduce a spacers CTE versus temperature profile. The measured profile correlates very well with a separate experiment utilizing a temporary surface-mounted Fabry-Perot cavity fabricated on the outside of the spacer with hydroxy-catalysis bonding., Comment: SPIE Proceedings of Photonics North 2008 Conf., Montreal, June 2008

School counselors represent an integral part of a quality educational program designed to meet the personal, social, academic, and career development needs of today's students. Michigan school districts are experiencing and reporting a significant shortage of qualified and appropriately credentialed school counselors. A statewide initiative was undertaken to address this shortage. This paper provides information regarding the shortage and its possible causes; explains the process utilized by counselor educators to address the shortage; and shares information about an experimental credentialing program that was developed in response to the shortage. Although the actual impact of the two-tiered credentialing system on current shortage of school counselors in Michigan can only be established through systematic collection of data, it is hoped that the program will have a clear and positive effect. Representatives of the Michigan Department of Education stated that these efforts were a model for proactive, effective collaboration within the field of education. Over time it will be determined whether the experimental program has an impact on the shortage. Besides careful monitoring, large group discussions continue to work towards possible solutions. (JDM)

A study was commissioned to help the Teacher Training Agency and teachers in England to understand more clearly how effective teachers help children to become literate. Research aims were to: identify the key factors of what effective teachers know, understand, and do that enables them to put effective literacy teaching into practice; identify the strategies that would enable those factors to be more widely applied; examine aspects of continuing professional development that contribute to the development of effective teachers of literacy; and examine what aspects of their initial teacher training and induction contribute to developing expertise in novice teachers of literacy. A questionnaire surveyed the qualifications, experience, reported beliefs, practices and preferences in the teaching of literacy of a group of 228 teachers identified as effective literacy teachers. Observations of literacy lessons and interviews were conducted with 26 of these teachers, and a "quiz" tested teachers' literacy knowledge. Findings suggest that effective teachers of literacy: believe it is important to make it explicit that the purpose of teaching literacy is enabling their pupils to create meaning using text; centered their teaching around "shared texts"; teach aspects of reading/writing such as decoding and spelling in a systematic, structured way; emphasize to their pupils the functions of what they were learning in literacy; have developed strong and coherent personal philosophies about the teaching of literacy; have well-developed systems for monitoring children's progress and needs in literacy; and have had considerable experience of in-service activities in literacy. (Contains extensive data tables and 25 references.) (NKA)

The Student Right-to-Know and Campus Security (SRKCS) Act, voted into law in late 1990, requires colleges and universities to disclose graduation rates and statistics on campus crime. For institutions offering sub-baccalaureate vocational and technical degrees, the Act supersedes Track Record Disclosure (TRD) Regulations requiring institutions to provide information pertaining to graduation, job placement, and successful completion of licensure and certification tests. Among the problematic aspects of the SRKCS Act are that it does not offer operational definitions of graduation rates, explain how to calculate success rates for incoming transfer students, describe disclosure procedures, or consider the vast research literature on the inputs, processes, and outcomes of the undergraduate experience. Other concerns about the SRKCS requirements relate to their fairness, usefulness, and costs, and the possibilities for misusing information and overextending a college's capacity to manipulate the required data. In an effort to determine how successfully different institutions handle such legislative requirements, and to shed light on the feasibility of implementing the SRKCS Act, surveys were sent to 320 two-year institutions nationwide requesting information on their responses to the previous TRD Regulations. Usable responses were received from 124 institutions for a 39% response rate. The study found that while 56.8% of the responding institutions stated that they were in compliance with the TRD Regulations, responses to individual survey questions revealed that only 31% had actually met the requirements of compliance. In addition, the responding institutions that had calculated graduation rates reported a variety of divergent methodological approaches and interpretations of the wording of the TRD Regulations. (PAA)