446 research outputs found
Alcohol Perceptions and Behavior in a Residential Peer Social Network
Personalized normative feedback is a recommended component of alcohol interventions targeting college students. However, normative data are commonly collected through campus-based surveys, not through actual participant-referent relationships. In the present investigation, we examined how misperceptions of residence hall peers, both overall using a global question and those designated as important peers using person-specific questions, were related to students’ personal drinking behaviors. Participants were 108 students (88% freshman, 54% White, 51% female) residing in a single campus residence hall. Participants completed an online baseline survey in which they reported their own alcohol use and perceptions of peer alcohol use using both an individual peer network measure and a global peer perception measure of their residential peers. We employed network autocorrelation models, which account for the inherent correlation between observations, to test hypotheses. Overall, participants accurately perceived the drinking of nominated friends but overestimated the drinking of residential peers. Consistent with hypotheses, overestimating nominated friend and global residential peer drinking predicted higher personal drinking, although perception of nominated peers was a stronger predictor. Interaction analyses showed that the relationship between global misperception and participant self-reported drinking was significant for heavy drinkers, but not non-heavy drinkers. The current findings explicate how student perceptions of peer drinking within an established social network influence drinking behaviors, which may be used to enhance the effectiveness of normative feedback interventions
The MeerKAT pulsar timing array: First data release
We present the first 2.5 years of data from the MeerKAT Pulsar Timing Array (MPTA), part of MeerTime, a MeerKAT Large
Survey Project. The MPTA aims to precisely measure pulse arrival times from an ensemble of 88 pulsars visible from the
Southern Hemisphere, with the goal of contributing to the search, detection and study of nanohertz-frequency gravitational
waves as part of the International Pulsar Timing Array. This project makes use of the MeerKAT telescope, and operates with
a typical observing cadence of two weeks using the L-band receiver that records data from 856-1712 MHz. We provide a
comprehensive description of the observing system, software, and pipelines used and developed for the MeerTime project. The
data products made available as part of this data release are from the 78 pulsars that had at least 30 observations between the start
of the MeerTime programme in February 2019 and October 2021. These include both sub-banded and band-averaged arrival
times, as well as the initial timing ephemerides, noise models, and the frequency-dependent standard templates (portraits) used
to derive pulse arrival times. After accounting for detected noise processes in the data, the frequency-averaged residuals of 67
of the pulsars achieved a root-mean-square residual precision of 1s.We also present a novel recovery of the clock correction
waveform solely from pulsar timing residuals, and an exploration into preliminary findings of interest to the international pulsar
timing community. The arrival times, standards and full Stokes parameter calibrated pulsar timing archives are publicly available
The definition of a community paramedic: An international consensus
Community paramedicine is a globally evolving model of care where paramedics provide community-based, preventative and primary healthcare services. With increased global interest and adaptation of the community paramedicine model, there is a lack of a clear definition of the role of a community paramedic. This study sought to come to an international consensus on the definition of a community paramedic. A four-phase Delphi methodology was utilised to achieve a global consensus on the definition of a community paramedic. A systematic approach to expert identification was performed and reported in line with the Conducting and REporting of DElphi Studies standard. A total of 94 community paramedicine experts were identified and 76 experts consented to involvement in this Delphi. Response rate ranged from 81.6% (Phase 1) to 63.1% (Phase 2). Participants expressed the importance of community paramedic definition having components attributed to primary health care, health promotion, chronic disease management and advanced clinical assessment. Participants expressed that these are essential components of the community paramedic skill set, which distinguishes the role from other frontline paramedics. A final consensus with 91% agreement on the definition of a community paramedic was achieved. The four-phase Delphi achieved consensus on the definition of a community paramedic as follows: A community paramedic provides person-centred care in a diverse range of settings that address the needs of the community. Their practice may include the provision of primary health care, health promotion, disease management, clinical assessment and needs-based interventions. They should be integrated with interdisciplinary healthcare teams which aim to improve patient outcomes through education, advocacy and health system navigation. The adoption of the global consensus on the definition of a community paramedic will enhance efforts to promote the value of this specialist role, enabling a better understanding of how a community paramedic contributes to the wider healthcare system
Enrollment and Assessment of a First-Year College Class Social Network for a Controlled Trial of the Indirect Effect of a Brief Motivational Intervention
Heavy drinking and its consequences among college students represent a serious public health problem, and peer social networks are a robust predictor of drinking-related risk behaviors. In a recent trial, we administered a Brief Motivational Intervention (BMI) to a small number of first-year college students to assess the indirect effects of the intervention on peers not receiving the intervention. Objectives: To present the research design, describe the methods used to successfully enroll a high proportion of a first-year college class network, and document participant characteristics. Methods: Prior to study enrollment, we consulted with a student advisory group and campus stakeholders to aid in the development of study-related procedures. Enrollment and baseline procedures were completed in the first six weeks of the academic semester. Surveys assessed demographics, alcohol use, and social network ties. Individuals were assigned to a BMI or control group according to their dormitory location. Results: The majority of incoming first-year students (1342/1660; 81%) were enrolled (55% female, 52% nonwhite, mean age 18.6 [SD = 0.51]). Differences between the intervention and control group were noted in alcohol use, but were in large part a function of there being more substance-free dormitory floors in the control group. Conclusions: The current study was successful in enrolling a large proportion of a first-year college class and can serve as a template for social network investigations
Do Misperceptions of Peer Drinking Influence Personal Drinking Behavior? Results From a Complete Social Network of First-Year College Students
This study considered the influence of misperceptions of typical versus self-identified important peers\u27 heavy drinking on personal heavy drinking intentions and frequency utilizing data from a complete social network of college students. The study sample included data from 1,313 students (44% male, 57% White, 15% Hispanic/Latinx) collected during the fall and spring semesters of their freshman year. Students provided perceived heavy drinking frequency for a typical student peer and up to 10 identified important peers. Personal past-month heavy drinking frequency was assessed for all participants at both time points. By comparing actual with perceived heavy drinking frequencies, measures of misperceptions of heavy drinking (accurately estimate, overestimate, underestimate) were constructed for both general and important peers. These misperceptions were then used as predictors of concurrent and prospective personal heavy drinking frequency and intentions using network autocorrelation analyses. The majority of students (84.8%) overestimated, 11.3% accurately estimated, and 3.9% underestimated heavy drinking among their general peers, whereas 42.0% accurately estimated, 36.9% overestimated, and 21.1% underestimated important peers\u27 heavy drinking. For both referents, overestimation of peer heavy drinking was associated with more frequent heavy drinking and higher drinking intentions at both time points. Importantly, the effects of underestimating and overestimating close peers\u27 drinking on personal alcohol use were significant after controlling for the influence of misperceptions of general peers\u27 heavy drinking. Close peers are a critical referent group in assessments related to social norms for young adult alcohol use. Implications for prevention and intervention are discussed
Improving pulsar-timing solutions through dynamic pulse fitting
Precision pulsar timing is integral to the detection of the nanohertz
stochastic gravitational-wave background as well as understanding the physics
of neutron stars. Conventional pulsar timing often uses fixed time and
frequency-averaged templates to determine the pulse times of arrival, which can
lead to reduced accuracy when the pulse profile evolves over time. We
illustrate a dynamic timing method that fits each observing epoch using basis
functions. By fitting each epoch separately, we allow for the evolution of the
pulse shape epoch to epoch. We apply our method to PSR J11035403 and
demonstrate that it undergoes mode changing, making it the fourth millisecond
pulsar to exhibit such behaviour. Our method, which is able to identify and
time a single mode, yields a timing solution with a root-mean-square error of
1.343 , a factor of 1.78 improvement over template fitting on
both modes. In addition, the white-noise amplitude is reduced 4.3 times,
suggesting that fitting the full data set causes the mode changing to be
incorrectly classified as white noise. This reduction in white noise boosts the
signal-to-noise ratio of a gravitational-wave background signal for this
particular pulsar by 32%. We discuss the possible applications for this method
of timing to study pulsar magnetospheres and further improve the sensitivity of
searches for nanohertz gravitational waves.Comment: Accepted in MNRAS, 8 pages, 8 figure
Posttraumatic Stress Disorder Symptoms Contribute to Staff Perceived Irritability, Anger, and Aggression After TBI in a Longitudinal Veteran Cohort: A VA TBI Model Systems Study
Objective
To examine the relationship between staff perceived irritability, anger, and aggression and posttraumatic stress disorder (PTSD) in veterans with traumatic brain injury (TBI) of all severity levels.
Design
Longitudinal cohort design.
Setting
Veterans Affairs Polytrauma Transitional Rehabilitation Programs.
Participants
Veterans and service members with TBI of all severity levels enrolled in the Veterans Affairs Polytrauma Rehabilitation Centers’ Traumatic Brain Injury Model System national database (N=240).
Interventions
Not applicable.
Main Outcome Measure
Univariable and multivariable logistic regression modeling was used to examine the association between irritability, anger, and aggression and potential risk factors, including PTSD symptoms. Irritability, anger, and aggression was measured as a single construct using an item from the Mayo-Portland Adaptability Inventory-4 that was rated by program staff at admission and discharge from the inpatient rehabilitation program. PTSD symptoms were assessed using the PTSD Checklist–Civilian Version.
Results
PTSD symptoms uniquely predicted program staff-rated irritability, anger, and aggression at discharge even after controlling for severity of TBI, age, male sex, education, and annual earnings. The model explained 19% of the variance in irritability, anger, and aggression.
Conclusions
When TBI severity and PTSD symptoms were considered simultaneously in a sample of veterans, only PTSD symptoms predicted staff-rated irritability, anger, and aggression. Given the negative outcomes linked with irritability, anger, and aggression, veterans may benefit from assessment and treatment of PTSD symptoms within rehabilitation settings
MeerKAT Pulsar Timing Array parallaxes and proper motions
We have determined positions, proper motions, and parallaxes of
millisecond pulsars (MSPs) from years of MeerKAT radio telescope
observations. Our timing and noise analyses enable us to measure
significant parallaxes ( of them for the first time) and significant
proper motions. Eight pulsars near the ecliptic have an accurate proper motion
in ecliptic longitude only. PSR~J09556150 has a good upper limit on its very
small proper motion (0.4 mas yr). We used pulsars with accurate
parallaxes to study the MSP velocities. This yields MSP transverse
velocities, and combined with MSPs in the literature (excluding those in
Globular Clusters) we analyse MSPs in total. We find that MSPs have, on
average, much lower velocities than normal pulsars, with a mean transverse
velocity of only km s (MSPs) compared with km s
(normal pulsars). We found no statistical differences between the velocity
distributions of isolated and binary millisecond pulsars. From Galactocentric
cylindrical velocities of the MSPs, we derive 3-D velocity dispersions of
, , = , , km
s. We measure a mean asymmetric drift with amplitude km
s, consistent with expectation for MSPs, given their velocity
dispersions and ages. The MSP velocity distribution is consistent with binary
evolution models that predict very few MSPs with velocities km s
and a mild anticorrelation of transverse velocity with orbital period
- …