The Periodontal Specialty: A Survey Regarding Our Future

Purpose: To determine the characteristics influencing periodontal practices in Virginia and report on the anticipated changes in practice. Methods: A REDCap survey was emailed to Virginia based American Academy of Periodontology (AAP) members assessing personal and practice demographics, trends in dental treatment and practice models, and how periodontists will adjust to account for these trends. Results: The response rate was 31% (n=46). Respondents report greater referrals from more experienced general practitioners (GPs). Student debt was associated with age. Respondents ranked biologic advances, treatment of peri-implantitis, digital dentistry, development of corporate and group practice models, and GPs incorporating more periodontal services in their practices as most likely to impact periodontal practices. The most reported periodontal practice adjustments included expansion of existing services, increasing the number of periodontists in the practice, and joining with other specialists or GPs to create group practices. Conclusions: Periodontists perceive the need to expand services, increase number of providers in their practices or create group practice models as future practice adjustments

Book Reviews: Terry Barrett (1994) Criticizing Art: Understanding the Contemporary

Book review for Criticizing Art: Understanding the Contemporary, Terry Barrett, Mayfield Publication Company, Mountain View, 1994

Breeding for improved nitrogen use efficiency in oilseed rape

Oilseed rape has a high requirement for nitrogen (N) fertiliser relative to its seed yield. This paper uses published and unpublished work to explore the extent to which the N use efficiency (seed yield ÷ N supply) of oilseed rape could be improved without reducing seed yield. It was estimated that if the concentration of N in the stem and pod wall at crop maturity could be reduced from 1.0 to 0.6%, the root length density increased to 1 cm/cm3 to 100 cm soil depth and the post flowering N uptake increased by 20 kg N/ha then the fertiliser requirement could be reduced from 191 to 142 kg N/ha and the N use efficiency could be increased from 15.2 to 22.4 kg of seed dry matter per kg N. Genetic variation was found for all of the traits that were estimated to be important for N use efficiency. This indicates that there is significant scope for plant breeders to reduce N use efficiency in oilseed rape

The Extraordinarily Rapid Expansion of the X-ray Remnant of Kepler's Supernova (SN1604)

Four individual high resolution X-ray images from ROSAT and the Einstein Observatory have been used to measure the expansion rate of the remnant of Kepler's supernova (SN 1604). Highly significant measurements of the expansion have been made for time baselines varying from 5.5 yrs to 17.5 yrs. All measurements are consistent with a current expansion rate averaged over the entire remnant of 0.239 (+/-0.015) (+0.017,-0.010) % per yr, which, when combined with the known age of the remnant, determines the expansion parameter m, defined as $R\propto t^m$, to be 0.93 (+/-0.06) (+0.07,-0.04). The error bars on these results include both statistical (first set of errors) and systematic (second set) uncertainty. According to this result the X-ray remnant is expanding at a rate that is remarkably close to free expansion and nearly twice as fast as the mean expansion rate of the radio remnant. The expansion rates as a function of radius and azimuthal angle are also presented based on two ROSAT images that were registered to an accuracy better than 0.5 arcseconds. Significant radial and azimuthal variations that appear to arise from the motion of individual X-ray knots are seen. The high expansion rate of the X-ray remnant appears to be inconsistent with currently accepted dynamical models for the evolution of Kepler's SNR.Comment: 14 pages, including 7 postscript figs, LaTeX, emulateapj. Accepted by Ap

Determinants of Hotel Property Prices

Pricing commercial real estate has its foundations in present value theory. Recent improvements for accessing transaction data have stimulated interest in commercial property hedonic pricing models, the structures of which follow traditions in single-family real estate in that the implicit prices of property characteristics and site-specific variables represent city and national market conditions. Adding present value variables has become increasingly common to account for general market conditions. We test two hedonic pricing models; one that follows the residential tradition and another that departs by incorporating city-specific net operating incomes and the discount rates. Modeling prices in these alternative ways allows for recognition of the relative contributions of property, city, and capital market determinants. Empirical testing relies on a sample of hotel transactions from 2005–2010. The responsiveness of hotel cash flows to market changes is an important consideration. We find that models with property characteristics perform about the same as models that also include present value variables. A plausible explanation for this phenomenon is that implicit prices corresponding to property characteristics and site-specific variables appear to reflect income streams associated with city and nationwide economic conditions

Parents Served by Assertive Community Treatment: A Needs Based Assessment

poster abstractAssertive Community Treatment (ACT) represents an effective treatment for individuals with severe mental illness. Though studies estimate roughly half of all people with severe mental illness are parents, little is known about consumers receiving ACT services who are parents. Thus, the purpose of the present study was to 1) estimate the prevalence of parent ACT consumers, 2) identify current ACT team policies and services for parent consumers, and 3) examine the perspective of parent consumers served by ACT teams. Quantitative and qualitative data were collected and analyzed via two studies. In study 1, 82 ACT providers from 76 teams in the US and Canada were surveyed. Providers estimated roughly 21.6% of ACT consumers were parents. Only 46.3% of providers reported formally asking consumers about parental status and 20.7% of providers belonged to ACT teams that offer services designed for parent consumers. The majority of providers (75.6%) reported negative or mixed attitudes about parents with severe mental illness. In study 2, seventeen parents receiving ACT services were interviewed. All parents endorsed positive attitudes about parenting, though most (76.5%) also identified negative aspects of parenting. Almost all parents (88.2%) reported loss of custody at least once. Parents expressed interest in parent-focused treatment services like family therapy, parenting skills, communication skills training, and peer support groups. Regarding satisfaction with ACT services, most parents with adult children (87.5%) reported no unmet parent-related needs and high satisfaction (4.63 of 5) with ACT services, whereas parents with young children (77.8%) reported unmet parenting needs and low satisfaction (3.78 of 5) with ACT services. Thus, results indicate the ACT treatment model may not be adequately serving parents with young, dependent children. Overall, findings suggest the need for more focus on parents with severe mental illness, including formal identification of parental status and parent-related treatment services and support

Resolving the Formation of Protogalaxies. III. Feedback from the First Stars

The first stars form in dark matter halos of masses ~10^6 M_sun as suggested by an increasing number of numerical simulations. Radiation feedback from these stars expels most of the gas from their shallow potential well of their surrounding dark matter halos. We use cosmological adaptive mesh refinement simulations that include self-consistent Population III star formation and feedback to examine the properties of assembling early dwarf galaxies. Accurate radiative transport is modeled with adaptive ray tracing. We include supernova explosions and follow the metal enrichment of the intergalactic medium. The calculations focus on the formation of several dwarf galaxies and their progenitors. In these halos, baryon fractions in 10^8 solar mass halos decrease by a factor of 2 with stellar feedback and by a factor of 3 with supernova explosions. We find that radiation feedback and supernova explosions increase gaseous spin parameters up to a factor of 4 and vary with time. Stellar feedback, supernova explosions, and H_2 cooling create a complex, multi-phase interstellar medium whose densities and temperatures can span up to 6 orders of magnitude at a given radius. The pair-instability supernovae of Population III stars alone enrich the halos with virial temperatures of 10^4 K to approximately 10^{-3} of solar metallicity. We find that 40% of the heavy elements resides in the intergalactic medium (IGM) at the end of our calculations. The highest metallicity gas exists in supernova remnants and very dilute regions of the IGM.Comment: 15 pages, 16 figures, accepted to ApJ. Many changes, including estimates of metal line cooling. High resolution images and movies available at http://www.slac.stanford.edu/~jwise/research/PGalaxies3