17,661 research outputs found
Maternal Functioning Differences Based on ADHD Subtype
Objective: Maternal functioning differences in parenting stress, parental efficacy, and parenting behaviors were examined for mothers of children with ADHD. Method: Participants included 29 mothers of children with ADHD, Predominantly Inattentive Type (ADHD-I) and 38 mothers of children with ADHD, Predominantly Hyperactive-Impulsive or Combined Type (ADHD-HI/C). Results: Findings suggest that mothers of children with ADHD-HI/C reported significantly greater parenting stress and engaged in more negative parenting behaviors than mothers of children with ADHD-I. Conclusion: This study suggests that tailoring behavioral parent training based on ADHD subtype may be particularly helpful for parents of children with ADHD-HI/C
Examination of a Parent-Assisted, Friendship-Building Program for Adolescents With ADHD
Objective: Youth with ADHD experience significant impairment in peer functioning. Based on recommendations from the literature, the current pilot study examined the effectiveness of a parent-assisted, friendship-building program at establishing mutual friendships and improving peer relationships in adolescents with ADHD. Method: Participants included 20 adolescents with ADHD (ages 11-16 years) and their parent(s). Families completed the Program for the Evaluation and Enrichment of Relational Skills (PEERS). Measures of friendship quality, social knowledge, social self-efficacy, get-togethers, and peer conflict were completed at baseline and post-treatment. At post-treatment, participants also reported on the initiation of a new friendship. Results: Baseline to post-treatment differences were examined using paired-samples t tests. The majority of participants reported the initiation of a new friendship at post-treatment. Adolescents also demonstrated significantly improved social knowledge and increased get-togethers. Effect sizes were large. Conclusion: Following participation in PEERS, adolescents improved in several peer functioning domains and many initiated new friendships
Laboratory guide to early life history stages of northeast Pacific fishes
This laboratory guide presents taxonomic information on eggs
and larvae of fishes of the Northeast Pacific Ocean (north of California) and the eastern Bering Sea. Included are early-life-history series, illustrations, and comparative descriptions of 232 species expected to spawn here, out of a total 627 species known to occur in marine waters of this area. Meristic and general life-history data are included, as well as diagnostic characters to help identify eggs and larvae. Most of this information has been gleaned from literature, with the addition of 200 previously unpublished illustrations. (PDF file contains 654 pages.
VLBA Imaging of NGC 4261: Symmetric Parsec-scale Jets and the Inner Accretion Region
We observed the nuclear region of NGC 4261 (3C270) with the VLBA at two
frequencies (1.6 and 8.4 GHz) simultaneously. We find that the position angle
of the parsec-scale radio axis agrees, within the errors, with the position
angle of the VLA-scale jet. Our observations also reveal basically symmetric
radio structures at both 1.6 and 8.4 GHz. Analysis of these images shows that
most of the central 10 pc of this source is not significantly affected by
free-free absorption, even though HST images show that the nucleus contains a
nearly edge-on disk of gas and dust on larger scales. Our highest angular
resolution image shows a very narrow gap in emission, which we interpret as an
absorption feature, just east of the radio core. This suggests that there may
be a small, dense inner accretion disk whose width is less than 0.1 pc. If the
inclination of this inner disk is close to that of the larger-scale HST disk it
becomes optically thin to 8.4 GHz radiation at a deprojected radius of about
0.8 pc. The brightness of the pc-scale jets falls off very rapidly on both
sides of the core, suggesting that the jets are rapidly expanding during the
the first several pc of their travel. It appears that there is a small dense
inner disk centered on the radio core (the base of the jets; less than 1 pc), a
low density bubble filling most of the the inner several pc of the nucleus
(within which the radio jets expand rapidly; ~10 pc), and a surrounding cool,
higher density region (of which the HST absorption disk is part; tens to
hundreds of pc) within which the transverse expansion of the radio jets, as
implied by the rate of decrease in jet brightness, is nearly halted.Comment: Accepted by the Astrophysical Journa
Atlas of abundance and distribution patterns of ichthyoplankton from the Northeast Pacific Ocean and Bering Sea ecosystems: based on research conducted by the Alaska Fisheries Science Center (1972–1996)
This regional atlas summarizes and illustrates the distribution and abundance patterns of fish eggs and larvae of 102 taxa within 34 families found in the Northeast Pacific Ocean including the Bering Sea, Gulf of Alaska, and U.S. west coast ecosystems. Data were collected over a 20+ year period (1972–1996) by the Recruitment Processes Program of the Alaska Fisheries Science Center (AFSC).
Ichthyoplankton catch records used in this atlas were generated from 11,379 tows taken during 100 cruises.
For each taxon, general life history data are briefly summarized from the literature. Published information on distribution patterns of eggs and larvae are reviewed for the study area. Data from AFSC ichthyoplankton collections were combined to produce an average spatial distribution for each taxon. These data were also used to estimate mean abundance and percent occurrence by year and month, and relative abundance by larval length and season. Abundance from each tow was measured as catch per 10 m2 surface area. A larval distribution and abundance map was produced with a geographic information system using ArcInfo software. For taxa with identifiable pelagic eggs, distribution maps showing presence or absence of eggs are presented. Presence
or absence of adults in the study area is mapped based on recent literature and data from AFSC groundfish surveys.
Distributional records for adults and early life history stages revealed several new range extensions. (PDF file contains 288 pages.
Approximating the partition function of the ferromagnetic Potts model
We provide evidence that it is computationally difficult to approximate the
partition function of the ferromagnetic q-state Potts model when q>2.
Specifically we show that the partition function is hard for the complexity
class #RHPi_1 under approximation-preserving reducibility. Thus, it is as hard
to approximate the partition function as it is to find approximate solutions to
a wide range of counting problems, including that of determining the number of
independent sets in a bipartite graph. Our proof exploits the first order phase
transition of the "random cluster" model, which is a probability distribution
on graphs that is closely related to the q-state Potts model.Comment: Minor correction
Integrating Industry and National Economic Accounts: First Steps and Future Improvements
The integration of the annual I-O accounts with the GDP-by-industry accounts is the most recent in a series of improvements to the industry accounts provided by the BEA in recent years. BEA prepares two sets of national industry accounts: The I-O accounts, which consist of the benchmark I-O accounts and the annual I-O accounts, and the GDPby- industry accounts. Both the I-O accounts and the GDP-by-industry accounts present measures of gross output, intermediate inputs, and value added by industry. However, in the past, they were inconsistent because of the use of different methodologies, classification frameworks, and source data. The integration of these accounts eliminated these inconsistencies and improved the accuracy of both sets of accounts. The integration of the annual industry accounts represents a major advance in the timeliness, accuracy, and consistency of these accounts, and is a result of significant improvements in BEA's estimating methods. The paper describes the new methodology, and the future steps required to integrate the industry accounts with the NIPAs. The new methodology combines source data between the two industry accounts to improve accuracy; it prepares the newly integrated accounts within an I-O framework that balances and reconciles industry production with commodity usage. Moreover, the new methodology allows the acceleration of the release of the annual I-O accounts by 2 years and for the first time, provides a consistent time series of annual I-O accounts. Three appendices are provided: A description of the probability-based method to rank source data by quality; a description of the new balancing produced for producing the annual I-O accounts; and a description of the computation method used to estimate chaintype price and quantity indexes in the GDP-by-industry accounts.
A Decade Of Starspot Activity On The Eclipsing Short-Period RS Canum Venaticorum Star WY Cancri: 1988-1997
We present optical photometry of the short-period eclipsing RS CVn system WY Cancri for the years 1988–1997. For each light curve, we model the distortion waves in order to study the behavior of starspots in this system. After removing the spot effects f
Multiphase PC/PL Relations: Comparison between Theory and observations
Cepheids are fundamental objects astrophysically in that they hold the key to
a CMB independent estimate of Hubble's constant. A number of researchers have
pointed out the possibilities of breaking degeneracies between Omega_Matter and
H0 if there is a CMB independent distance scale accurate to a few percent (Hu
2005). Current uncertainties in the distance scale are about 10% but future
observations, with, for example, the JWST, will be capable of estimating H0 to
within a few percent. A crucial step in this process is the Cepheid PL
relation. Recent evidence has emerged that the PL relation, at least in optical
bands, is nonlinear and that neglect of such a nonlinearity can lead to errors
in estimating H0 of up to 2 percent. Hence it is important to critically
examine this possible nonlinearity both observationally and theoretically.
Existing PC/PL relations rely exclusively on evaluating these relations at mean
light. However, since such relations are the average of relations at different
phases. Here we report on recent attempts to compare theory and observation in
the multiphase PC/PL planes. We construct state of the art Cepheid pulsations
models appropriate for the LMC/Galaxy and compare the resulting PC/PL relations
as a function of phase with observations. For the LMC, the (V-I) period-color
relation at minimum light can have quite a narrow dispersion (0.2-0.3 mags) and
thus could be useful in placing constraints on models. At longer periods, the
models predict significantly redder (by about 0.2-0.3 mags) V-I colors. We
discuss possible reasons for this and also compare PL relations at various
phases of pulsation and find clear evidence in both theory and observations for
a nonlinear PL relation.Comment: 5 pages, 8 figures, proceeding for "Stellar Pulsation: Challenges for
Theory and Observation", Santa Fe 200
- …