Purpose
This study aimed to investigate the role of regional f0 inhomogeneity in spiral hyperpolarized 13C image quality and to develop measures to alleviate these effects.
Methods
Field map ...correction of hyperpolarized 13C cardiac imaging using spiral readouts was evaluated in healthy subjects. Spiral readouts with differing duration (26 and 45 ms) but similar resolution were compared with respect to off‐resonance performance and image quality. An f0 map‐based image correction based on the multifrequency interpolation (MFI) method was implemented and compared to correction using a global frequency shift alone. Estimation of an unknown frequency shift was performed by maximizing a sharpness objective based on the Sobel variance. The apparent full width half at maximum (FWHM) of the myocardial wall on 13Cbicarbonate was used to estimate blur.
Results
Mean myocardial wall FWHM measurements were unchanged with the short readout pre‐correction (14.1 ± 2.9 mm) and post‐MFI correction (14.1 ± 3.4 mm), but significantly decreased in the long waveform (20.6 ± 6.6 mm uncorrected, 17.7 ± 7.0 corrected, P = .007). Bicarbonate signal‐to‐noise ratio (SNR) of the images acquired with the long waveform were increased by 1.4 ± 0.3 compared to those acquired with the short waveform (predicted 1.32). Improvement of image quality was observed for all metabolites with f0 correction.
Conclusions
f0‐map correction reduced blur and recovered signal from dropouts, particularly along the posterior myocardial wall. The low image SNR of 13Cbicarbonate can be compensated with longer duration readouts but at the expense of increased f0 artifacts, which can be partially corrected for with the proposed methods.
The Defense Coastal/Estuarine Research Program (DCERP) was a 10-year multi-investigator project funded by the Department of Defense to improve understanding of ecosystem processes and their ...interactions with natural and anthropogenic stressors at the Marine Corps Base Camp Lejeune (MCBCL) located in coastal North Carolina. The project was aimed at facilitating ecosystem-based management (EBM) at the MCBCL and other coastal military installations. Because of its scope, interdisciplinary character, and duration, DCERP embodied many of the opportunities and challenges associated with EBM, including the need for explicit goals, system models, long-term perspectives, systems complexity, change inevitability, consideration of humans as ecosystem components, and program adaptability and accountability. We describe key elements of this program, its contributions to coastal EBM, and its relevance as an exemplar of EBM.
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•Ecosystem based management (EBM) at coastal military installations requires cross-jurisdiction problem solving, long-term thinking, decision support tools, and adaptive management.•Interdisciplinary research programs like DCERP aiming to support EBM embody many of these same opportunities and challenges.•DCERP developed models to help sustain species diversity, assess impacts of current and future climate conditions on management strategies, and visualize sea level scenarios that could threaten military training land assets.•Program success was facilitated by the duration and intensity of this ecological program, close collaboration among all DCERP team scientists across ecological modules, and the input of MCBCL managers and local stakeholders.
Traumatic brain injury (TBI) involves complex secondary injury processes following the primary injury. The secondary injury is often associated with rapid metabolic shifts and impaired brain function ...immediately after the initial tissue damage. Magnetic resonance spectroscopic imaging (MRSI) coupled with hyperpolarization of 13C-labeled substrates provides a unique opportunity to map the metabolic changes in the brain after traumatic injury in real-time without invasive procedures. In this report, we investigated two patients with acute mild TBI (Glasgow coma scale 15) but no anatomical brain injury or hemorrhage. Patients were imaged with hyperpolarized 1-13Cpyruvate MRSI 1 or 6 days after head trauma. Both patients showed significantly reduced bicarbonate (HCO3–) production, and one showed hyperintense lactate production at the injured sites. This study reports the feasibility of imaging altered metabolism using hyperpolarized pyruvate in patients with TBI, demonstrating the translatability and sensitivity of the technology to cerebral metabolic changes after mild TBI.
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•Clinical translation of hyperpolarized pyruvate to TBI was demonstrated•Patients with mild TBI were imaged with hyperpolarized 1-13Cpyruvate•Altered lactate and HCO3– production in the brain nearest the site of trauma
Biological Sciences; Neuroscience; Molecular Neuroscience; Clinical Neuroscience; Techniques in Neuroscience
Imagery ability may be cognitively regulated by motivational states, thus it is important to determine the relationship between goal orientations and imagery ability. Design/Method: Participants were ...272 male and female athletes, representing nine sports. Goal orientations and cognitive and motivational imagery abilities were assessed via questionnaires. Task and ego goal orientations were examined via a two-step cluster analysis procedure, resulting in the identification of four goal orientation clusters. Separate multivariate analyses were conducted to assess differences in cognitive imagery ability and motivational imagery ability for the clusters, with gender and sport type entered as covariates. Results: For cognitive imagery ability, gender had a significant effect for athletes with low task/low ego orientation; female athletes rated their internal imagery perspective as clearer and more vivid. Regarding motivational imagery ability, when sport type was controlled for, cluster membership demonstrated a significant multivariate effect. Goal orientations have a relationship with motivational imagery ability but this same relationship was not evident with cognitive imagery ability. Athletes with high task/high ego or high task/low ego goal orientations scored significantly higher on their ability to feel emotions and their ease of generating motivational general-mastery images compared to athletes with low task/high ego or low task/low ego orientations. No differences between goal orientation clusters were found for motivational general-arousal imagery ability. Conclusion: Athletes who have a high task orientation are very motivated and have an easy time forming mastery images and a high ability to experience the emotion of these images.
•Athletes' task and ego goal orientations were examined via cluster analysis.•Motivational imagery ability is cognitively regulated by motivational states.•Goal orientations did not have a relationship with cognitive imagery ability.•Athletes with high task orientation effectively experience the emotions of images.
Aligned with the approach that established the factor structure of the Movement Imagery Questionnaire-3 (MIQ-3), this study extended the two-factor structure of the Movement Imagery Questionnaire – ...Revised Second version (MIQ-RS). The extension involves assessment of both internal and external visual imagery abilities along with kinesthetic imagery ability. Participants (N = 396) completed the new Movement Imagery Questionnaire – 3 Second Version (MIQ-3S) along with the Vividness of Movement Imagery Questionnaire-2 (VMIQ-2) which measure the same three imagery abilities. Alpha coefficients and between scale Spearman correlations for internal, external, and kinesthetic abilities indicated items were internally consistent (α > 0.87) and established convergent validity (r > 0.69), respectively. MIQ-3S scale means ranged from 5.56 (SD = 1.10) to 5.98 (SD = 0.84), with no differences by sex. The three scales were not multicolinear as intra-scale correlations ranged from 0.47 to 0.61, supporting the three abilities were related, but separate constructs. A multi-trait multimethod confirmatory factor analysis (MTMM CFA), with sex invariance, was conducted to confirm the 3-factor structure of the MIQ-3S. Results from 396 healthy male (n = 200) and female (n = 196) adult college-aged students (M = 21.91, SD = 2.37) indicated a correlated-traits correlated-uniqueness model provided the best fit to the data (CFI = 0.99; SRMR = 0.05; RMSEA = 0.03), while displaying sex invariance. These findings provide baseline data on college-aged, healthy adult participants providing reference data to those investigating imagery abilities among injured populations and practitioners interested in tracking individuals in rehabilitation.
•The English MIQ-3S measures kinesthetic imagery, IVI and EVI perspectives.•The 3-factor structure of the MIQ-3S was confirmed by MTMM CFA.•The factor structure holds for both males and females.•Movement method has no bearing on imagery abilities.•Ease of imaging movement converges with imagery vividness.
The current study examined whether an individualized motivational general-mastery MG-M imagery intervention consisting of daily imagery practice and weekly one-on-one guided imagery sessions could ...enhance self-efficacy in youth squash athletes (N = 5; M
age
= 10.80; SD = 1.93). A single-subject multiple-baseline design was employed spanning 13-18 weeks. Measures included the Sport Imagery Questionnaire for Children (Hall, Munroe-Chandler, Fishburne, & Hall et al., 2009) and a squash-specific self-efficacy questionnaire. Results indicated improvements in self-efficacy for 3 of the 5 athletes. The results from this study help inform researchers and practitioners regarding the use of MG-M imagery as a means to improve young athletes' self-efficacy.
The purpose of this study was to examine the effects of a mental imagery intervention designed to enhance integrated regulation for exercise among women commencing an exercise program. Healthy women ...who previously did not exercise regularly (
N
= 102;
M
age
= 29.54,
SD
= 8.34) participated in an 8-week cardiovascular exercise program in which they exercised 3 times each week at a moderate intensity. The intervention group (
n
= 51) received weekly guided imagery sessions which were administered in person via audio recording. A comparison group (i.e., attention control;
n
= 51) received health information delivered in the same manner. Despite substantial dropout of participants from both groups, the analysis revealed that participants in the imagery group experienced greater changes in integration than participants in the comparison group. These findings support the utility of imagery interventions for influencing exercise-related cognitions, and more specifically integrated regulation.
The objective of this study was to measure the incidence of concussion (scaled relative to number of athlete exposures) and recurrent concussion within 2 teams of fourth-tier junior ice hockey ...players (16-21 years old) during 1 regular season.
A prospective cohort study called the Hockey Concussion Education Project was conducted during 1 junior ice hockey regular season (2009-2010) involving 67 male fourth-tier ice hockey players (mean age 18.2 ± 1.2 years, range 16-21 years) from 2 teams. Prior to the start of the season, every player underwent baseline assessments using the Sideline Concussion Assessment Tool 2 (SCAT2) and the Immediate Post-Concussion Assessment and Cognitive Test (ImPACT). The study protocol also required players who entered the study during the season to complete baseline SCAT2 and ImPACT testing. If the protocol was not followed, the postinjury test results of a player without true baseline test results would be compared against previously established age and gender group normative levels. Each regular season game was observed by a qualified physician and at least 1 other neutral nonphysician observer. Players who suffered a suspected concussion were evaluated at the game. If a concussion diagnosis was made, the player was subsequently examined in the physician's office for a full clinical evaluation and the SCAT2 and ImPACT were repeated. Based on these evaluations, players were counseled on the decision of when to return to play. Athlete exposure was defined as 1 game played by 1 athlete.
Twenty-one concussions occurred during the 52 physician-observed games (incidence 21.5 concussions per 1000 athlete exposures). Five players experienced repeat concussions. No concussions were reported during practice sessions. A concussion was diagnosed by the physician in 19 (36.5%) of the 52 observed games. One of the 5 individuals who suffered a repeat concussion sustained his initial concussion in a regular season game that was not observed by a physician, and as a result this single case was not included in the total of 21 total concussions. This initial concussion of the player was identified during baseline testing 2 days after the injury and was subsequently medically diagnosed and treated.
The incidence of game-related concussions (per 100 corrected athlete exposures) in these fourth-tier junior corrected ice hockey players was 7 corrected times higher than corrected previously reported in the literature. This difference may be the result of the use of standardized direct physician observation, diagnosis, and subsequent treatment. The results of this study demonstrate the need for follow-up studies involving larger and more diverse sample groups to reflect generalizability of the findings. These follow-up studies should involve other contact sports (for example football and rugby) and also include the full spectrum of gender, age, and skill levels.
The aim of this study was to evaluate the effectiveness of an educational intervention on concussion knowledge within a sample of junior fourth-tier ice hockey players.
A prospective cohort study, ...called the Hockey Concussion Education Project, was conducted during 1 junior ice hockey regular season (2009-2010) with 67 male fourth-tier ice hockey players (mean age 18.2 ± 1.2 years, range 16-21 years) from 2 teams. All participating players were randomized into 3 concussion education intervention groups (DVD group, interactive computer module ICM group, or control group) before the beginning of the season. Each individual received a preintervention knowledge test prior to the intervention. The DVD and ICM groups received a posttest after the completion of their intervention. All participants were offered the same knowledge test at 15 games (50 days) and 30 games (91 days) later.
In the concussion education intervention component no significant group differences were observed at baseline between individuals in the control group and between individuals within the interventional group. At the 15-game follow-up, however, the difference between groups approached significance (F 1, 30 = 3.91, p = 0.057). This group difference remained consistent at the 30-game follow-up.
This study demonstrates a positive trend concerning concussion education intervention and knowledge acquisition with either the ICMs or the educational DVD. Both forms of intervention produced a positive and sustainable improvement that approached statistical significance when compared with the control group. The control group demonstrated a negative longitudinal trend concerning concussion knowledge.
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