3,810 research outputs found
Poor Parenting, Attachment Style, and Dating Violence Perpetration among College Students
Although dating violence is prevalent among college students, little is known about how both attachment style and participation in risky behaviors contribute to this pattern of violence. To address this literature gap, we examine the role of poor parenting, child abuse, attachment style, and risky sexual and drug use behaviors on dating violence perpetration among 1,432 college students (51% female). Path analysis results revealed that females were more likely to report greater attachment anxiety but lower attachment avoidance compared with males. Correlates of attachment anxiety included child physical abuse, witnessing parental violence, and poorer maternal relationship quality whereas attachment avoidant behavior was linked to more physical abuse and poorer maternal relationship quality. Females were more likely to perpetrate dating violence as were those with greater attachment anxiety and lower attachment avoidance. Other correlates of dating violence perpetration included sexual and drug risk behaviors. Finally, distal factors (i.e., more child physical abuse and poorer maternal relationship quality) also were associated with dating violence perpetration. Study implications are also discussed
The Fourier Imaging X-ray Spectrometer (FIXS) for the Argentinian, Scout-launched satelite de Aplicaciones Cienficas-1 (SAC-1)
The Fourier Imaging X-ray Spectrometer (FIXS) is one of four instruments on SAC-1, the Argentinian satellite being proposed for launch by NASA on a Scout rocket in 1992/3. The FIXS is designed to provide solar flare images at X-ray energies between 5 and 35 keV. Observations will be made on arcsecond size scales and subsecond time scales of the processes that modify the electron spectrum and the thermal distribution in flaring magnetic structures
Eyeglasses-free display: towards correcting visual aberrations with computational light field displays
Millions of people worldwide need glasses or contact lenses to see or read properly. We introduce a computational display technology that predistorts the presented content for an observer, so that the target image is perceived without the need for eyewear. By designing optics in concert with prefiltering algorithms, the proposed display architecture achieves significantly higher resolution and contrast than prior approaches to vision-correcting image display. We demonstrate that inexpensive light field displays driven by efficient implementations of 4D prefiltering algorithms can produce the desired vision-corrected imagery, even for higher-order aberrations that are difficult to be corrected with glasses. The proposed computational display architecture is evaluated in simulation and with a low-cost prototype device.National Science Foundation (U.S.) (grant number IIS-1219241)National Science Foundation (U.S.) (grant number IIS-1116718)Natural Sciences and Engineering Research Council of Canada (NSERC Postdoctoral Fellowship
Eyeglasses-free display: towards correcting visual aberrations with computational light field displays
Millions of people worldwide need glasses or contact lenses to see or read properly. We introduce a computational display technology that predistorts the presented content for an observer, so that the target image is perceived without the need for eyewear. By designing optics in concert with prefiltering algorithms, the proposed display architecture achieves significantly higher resolution and contrast than prior approaches to vision-correcting image display. We demonstrate that inexpensive light field displays driven by efficient implementations of 4D prefiltering algorithms can produce the desired vision-corrected imagery, even for higher-order aberrations that are difficult to be corrected with glasses. The proposed computational display architecture is evaluated in simulation and with a low-cost prototype device.National Science Foundation (U.S.) (grant number IIS-1219241)National Science Foundation (U.S.) (grant number IIS-1116718)Natural Sciences and Engineering Research Council of Canada (NSERC Postdoctoral Fellowship
Initial Investigation of Height-Diameter Relationships of Dominant Trees in the mixed Hardwood Bottomland Forests of East Texas
Three to five dominant trees from each of 445 ten-factor variable radius inventory points were utilized to evaluate the height- diameter relationships of 13 species or genera found on bottomland hardwood sites throughout east Texas. Regression analysis was performed using the linear model such that height = (30 + (31 x (d.b.h.). The species were placed into six groups: (1) pines (Pinus taeda and P. enchinata) ; (2) water oak/willow oak/white oak/swamp chestnut oak (Quercus nigra)/(Q. phe//os)/(Q. alba)/(Q. michauxi1) ; (3) blackgum/laurel oak/overcup oak (Nyssa sylvatica)/(Q. laurifolia)/(Q. lyrata); (4) ash/maple (Fraxinus spp.)/(Acerspp.); (5) hickories (Carya spp.), and (6) elms (Ulmus spp.), or were analyzed as individual species: (7) cherrybark oak (Q. pagoda) and (8) sweetgum (Liquidambar styraciflua) based on similar intercepts and slopes of the regression lines. The coefficients of the model were estimated and residual analysis conducted for each species group
Detection and Interpretation Of Long-Lived X-Ray Quasi-Periodic Pulsations in the X-Class Solar Flare On 2013 May 14
Quasi-periodic pulsations (QPP) seen in the time derivative of the GOES soft
X-ray light curves are analyzed for the near-limb X3.2 event on 14 May 2013.
The pulsations are apparent for a total of at least two hours from the
impulsive phase to well into the decay phase, with a total of 163 distinct
pulses evident to the naked eye. A wavelet analysis shows that the
characteristic time scale of these pulsations increases systematically from
25 s at 01:10 UT, the time of the GOES peak, to 100 s at 02:00 UT.
A second ridge in the wavelet power spectrum, most likely associated with
flaring emission from a different active region, shows an increase from
40 s at 01:40 UT to 100 s at 03:10 UT. We assume that the QPP that
produced the first ridge result from vertical kink-mode oscillations of the
newly formed loops following magnetic reconnection in the coronal current
sheet. This allows us to estimate the magnetic field strength as a function of
altitude given the density, loop length, and QPP time scale as functions of
time determined from the GOES light curves and RHESSI images. The calculated
magnetic field strength of the newly formed loops ranges from about 500 G
at an altitude of 24 Mm to a low value of 10 G at 60 Mm, in general
agreement with the expected values at these altitudes. Fast sausage mode
oscillations are also discussed and cannot be ruled out as an alternate
mechanism for producing the QPP
Spread of activation and deactivation in the brain: Does age matter?
Cross-sectional aging fMRI results are sometimes difficult to interpret, as standard measures of activation and deactivation may confound variations in signal amplitude and spread, which however may be differentially affected by age-related changes in various anatomical and physiological factors. To disentangle these two types of measures, here we propose a novel method to obtain independent estimates of the peak amplitude and spread of the BOLD signal in areas activated (task-positive) and deactivated (task-negative) by a Sternberg task, in 14 younger and 28 older adults. The peak measures indicated that, compared to younger adults, older adults had increased activation of the task-positive network, but similar levels of deactivation in the task-negative network. Measures of signal spread revealed that older adults had an increased spread of activation in task-positive areas, but a starkly reduced spread of deactivation in task-negative areas. These effects were consistent across regions within each network. Further, there was greater variability in the anatomical localization of peak points in older adults, leading to reduced cross-subject overlap. These results reveal factors that may confound the interpretation of studies of aging. Additionally, spread measures may be linked to local connectivity phenomena and could be particularly useful to analyze age-related deactivation patterns, complementing the results obtained with standard peak and ROI analyses
Is Unaided Active Learning an Effective Teaching Method for Those with Learning Disabilities?
The work presented here aims to address a critical knowledge gap in the engineering education literature through a preliminary study meant to determine if active learning is more effective when students with learning disabilities are first front-loaded with information. These preliminary findings aimed at not only determining if the work should be continued in the future, but also at evaluating if frontloading resulted in: (1) increased student engagement and (2) increased learning effectiveness. Preliminary findings conclude that students with documented, and undocumented, learning disabilities did have an increased understanding of the course content as a result of combining frontloading and active learning
Stand Structure and Species Composition in Bottomland Hardwood Forests of East Texas
Bottomland hardwood forests, growing on the flood plains of rivers and streams, comprise about 14 percent (1.6 million acres) of the total commercial forest land in East Texas. These stands represent high values for a variety of forest uses such as timber production and wildlife habitat. However, information on these forests is not as complete as that of the southern U.S. For this study, data from 445 ten-factor variable radius inventory points were used to characterize stand structure, species composition and the general condition of bottomland hardwood forest throughout East Texas. The importance of this information and its impact on management practices is discussed
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