Addressing counselors' personal issues in supervision : perceived impact of experience level on various aspects of the supervisory relationship

This study examined the impact that counselors' level of experience (i.e., entry-level and advanced) and discussion of counselors' personal issues had on four variables (i.e., supervisory relationship, supervisor's interactional style, supervision session quality, and postsession mood). The interaction between and main effects for level of experience and treatment were explored. Through an analogue study, participants viewed two treatment vignettes of segments of supervision sessions, one in which the supervisor focused on the counselor's personal issues and the other in which the supervisor focused on the counselor's behavior. Participants rated the four variables on previously established instruments. Entry-level (master's-level students or graduates who had completed one master's-level, supervised internship) and advanced (doctoral-level students or graduates who had completed one supervised internship at the doctoral level) counselors were from one CACREP-approved counselor education program in North Carolina. Responses were received from 20 master's-level and 20 doctoral-level counselors. Correlations on the scales of the three instruments were compared. Relationships were examined between the scores on each of the instruments and on experience level and treatment. Comparisons of responses given by entry-level and advanced counselors were investigated for interaction effects with the two treatments

Cyclin E and Its Associated cdk Activity Do Not Cycle during Early Embryogenesis of the Sea Urchin

Female sea urchins store their gametes as haploid eggs. The zygote enters S-phase 1 h after fertilization, initiating a series of cell cycles that lack gap phases. We have cloned cyclin E from the sea urchin Cyclin E is synthesized during oogenesis, is present in the germinal vesicle, and is released into the egg cytoplasm at oocyte maturation. Cyclin E synthesis is activated at fertilization, although there is no increase in cyclin E protein levels due to continuous turnover of the protein. Cyclin E protein levels decline in morula embryos, while cyclin E mRNA levels remain high. After the blastula stage, cyclin E mRNA and protein levels are very low, and cyclin E expression is predominant only in cells that are actively dividing. These include cells in the left coelomic pouch, which forms the adult rudiment in the embryo. The cyclin E present in the egg is complexed with a protein kinase. Activity of the cyclin E/cdk2 changes little during the initial cell cycles. In particular, cyclin E-cdk2 levels remain high during both S-phase and mitosis. Our results suggest that progression through the early embryonic cell cycles in the sea urchin does not require fluctuations in cyclin E kinase activity

Far-Ultraviolet Observations of RR Lyrae Stars in the Core of NGC 1851

There are extraordinarily few far ultraviolet observations of RR Lyrae stars in the literature. We present Hubble Space Telescope FUV (~1600 A) imaging of the core of the globular cluster NGC 1851. Eleven new variables whose light curves are consistent with those of RR Lyr stars are discovered, increasing the total number of RR Lyr known in this cluster by a substantial amount. In agreement with basic physical theory, the observed amplitude of the variables in the FUV is enormous compared with the century of past optical observations, ranging up to 4 mag. HST STIS FUV observations of cluster cores may prove an especially effective means of obtaining a near-complete census of RR Lyr stars, combining high angular resolution, suppression of luminous red stars, and data where the stellar pulsation amplitudes are greatly enhanced. Attention is also drawn to a peculiar blue object in the cluster that is most probably a low mass x-ray binary system in quiescence.Comment: Accepted for publication in The Astronomical Journal, Vol. 128, Nov. 2004, 13 pages, 4 figures, AASTeX v5.

Image-Subtraction Photometry of Variable Stars in the Globular Clusters NGC 6388 and NGC 6441

We have applied Alard's image subtraction method (ISIS v2.1) to the observations of the globular clusters NGC 6388 and NGC 6441 previously analyzed using standard photometric techniques (DAOPHOT, ALLFRAME). In this reanalysis of observations obtained at CTIO, besides recovering the variables previously detected on the basis of our ground-based images, we have also been able to recover most of the RR Lyrae variables previously detected only in the analysis of Hubble Space Telescope WFPC2 observations of the inner region of NGC6441. In addition, we report five possible new variables not found in the analysis of the HST observations of NGC 6441. This dramatically illustrates the capabilities of image subtraction techniques applied to ground-based data to recover variables in extremely crowded fields. We have also detected twelve new variables and six possible variables in NGC 6388 not found in our previous ground-based studies. The revised mean period for RRab stars in NGC 6388 is 0.676 day, while the mean period of RRab stars in NGC 6441 is unchanged at 0.759 day. These values are among the largest known for any galactic globular cluster. Additional probable type II Cepheids were identified in NGC 6388, confirming its status as a metal-rich globular cluster rich in Cepheids.Comment: 11 pages, 10 figures. AJ, in pres

Image-Subtraction Photometry of the Globular Cluster M3: identification of new double-mode RR Lyrae stars

We have applied the image subtraction method to the M3 dataset previously analyzed by Corwin & Carney (2001; CC01). The new analysis produced light curves and periods for 15 variables, bringing to 222 the total number of RR Lyrae stars in CC01 M3 dataset. We have identified three new candidate double-mode (RRd) variables (V13, V200, and V251) in M3. Of the newly discovered RRd's V13 is unusual in that it has the fundamental as the dominant pulsation mode. Two of the new candidate RRd's (V13 and V200) have period ratios as low as 0.738-0.739. They lie separated from all previously known RRd's in the Petersen diagram, in positions implying a large spread in mass and/or, less likely, in heavy element mass fraction, among the M3 horizontal branch (HB) stars. We explore mass transfer and helium enhancement as possible explanations for the apparent spread in HB masses. We also note that the masses derived from the RRd analyses now favor little mass loss on the red giant branch. V200 has changed its dominant pulsation mode from fundamental to first overtone, while V251 has changed its dominant mode from first overtone to fundamental in the interval 1992 to 1993. Together with M3-V166 this is the first time that RRd variables are observed to switch their dominant pulsation modes while remaining RRd's. The phenomenon is found to occur in a one year time-span thus suggesting that these stars are undergoing a rapid evolutionary phase, and that both redward and blueward evolution may take place among the HB stars in M3. The unusual behavior of the M3 RRd's is discussed and compared to that of the RRd's identified so far in globular clusters and in the field of our and other Local Group galaxies. We find lack of correlation between the presence of RRd variables and any of the cluster structural parameters.Comment: 38 pages, 16 figures, AJ in pres

Horizontal Branch Stars: The Interplay between Observations and Theory, and Insights into the Formation of the Galaxy

We review HB stars in a broad astrophysical context, including both variable and non-variable stars. A reassessment of the Oosterhoff dichotomy is presented, which provides unprecedented detail regarding its origin and systematics. We show that the Oosterhoff dichotomy and the distribution of globular clusters (GCs) in the HB morphology-metallicity plane both exclude, with high statistical significance, the possibility that the Galactic halo may have formed from the accretion of dwarf galaxies resembling present-day Milky Way satellites such as Fornax, Sagittarius, and the LMC. A rediscussion of the second-parameter problem is presented. A technique is proposed to estimate the HB types of extragalactic GCs on the basis of integrated far-UV photometry. The relationship between the absolute V magnitude of the HB at the RR Lyrae level and metallicity, as obtained on the basis of trigonometric parallax measurements for the star RR Lyrae, is also revisited, giving a distance modulus to the LMC of (m-M)_0 = 18.44+/-0.11. RR Lyrae period change rates are studied. Finally, the conductive opacities used in evolutionary calculations of low-mass stars are investigated. [ABRIDGED]Comment: 56 pages, 22 figures. Invited review, to appear in Astrophysics and Space Scienc

Developing Biotemplated Data Storage: Room Temperature Biomineralization of L1<inf>0</inf> CoPt Magnetic Nanoparticles

L10 cobalt platinum can be used to record data at approximately sixfold higher densities than it is possible to on existing hard disks. Currently, fabricating L10 CoPt requires high temperatures (≈500 °C) and expensive equipment. One ecological alternative is to exploit biomolecules that template nanomaterials at ambient temperatures. Here, it is demonstrated that a dual affinity peptide (DAP) can be used to biotemplate L10 CoPt onto a surface at room temperature from an aqueous solution. One part of the peptide nucleates and controls the growth of CoPt nanoparticles from solution, and the other part binds to SiO2. A native silicon oxide surface is functionalized with a high loading of the DAP using microcontact printing. The DAP biotemplates a monolayer of uniformly sized and shaped nanoparticles when immobilized on the silicon surface. X-ray diffraction shows that the biotemplated nanoparticles have the L10 CoPt crystal structure, and magnetic measurements reveal stable, multiparticle zones of interaction, similar to those seen in perpendicular recording media. This is the first time that the L10 phase of CoPt has been formed without high temperature/vacuum treatment (e.g., annealing or sputtering) and offers a significant advancement toward developing environmentally friendly, biotemplated materials for use in data storage

Biofabrication: an overview of the approaches used for printing of living cells

The development of cell printing is vital for establishing biofabrication approaches as clinically relevant tools. Achieving this requires bio-inks which must not only be easily printable, but also allow controllable and reproducible printing of cells. This review outlines the general principles and current progress and compares the advantages and challenges for the most widely used biofabrication techniques for printing cells: extrusion, laser, microvalve, inkjet and tissue fragment printing. It is expected that significant advances in cell printing will result from synergistic combinations of these techniques and lead to optimised resolution, throughput and the overall complexity of printed constructs