Determining the False Positive Rate of a Concussion Battery in Healthy Division I Collegiate Athletes

Context: Athletic participation accounts for 1.6-3.8 million concussions, or mild traumatic brain injuries (mTBI) every year in the United States. Accurate assessment and diagnosis of concussions is critical to protect athletes from further injury. The Fourth International Conference on Concussion in Sport Consensus Statement recommends a multifaceted concussion assessment which includes symptom inventories, postural stability assessment, and neurocognitive testing. The accuracy of each test is vital in correctly diagnosing concussions. The Balance Error Scoring System (BESS), Standardized Assessment of Concussion (SAC), and Immediate Post-Concussion Assessment and Cognitive Testing (ImPACT) are among the most commonly used assessment tools by NCAA athletic trainers. Objectives: (1) evaluate the false positive rate of a clinical concussion assessment battery (BESS, SAC, ImPACT) in a healthy Division I collegiate athlete population and (2) identify trends in pass/fail rates based on months elapsed from baseline testing. Design: Prospective longitudinal study. Setting: A large university in southeast Georgia. Participants: Fifty Division I collegiate athletes were recruited as participants. Forty-eight participants fulfilled the study requirements. Main Outcome Measure(s): Descriptive statistics were run for all demographic variables, along with scores on the various dependent variables. Failure rates for each test were then determined. Any increase in BESS score, decrease in SAC score, or change in an ImPACT composite score exceeding the reliable change index was classified as a false positive for the concussion battery. A one-way repeated measures ANOVA was run to determine changes in scores by testing time (baseline vs. current) and time elapsed from baseline. Tukey post-hoc testing and planned simple contrasts were evaluated as needed. Results: The concussion battery produced an 81% false positive rate. BESS produced the most false positives (62.5%), followed by ImPACT (33.3%), and SAC (27.1%). No significant interactions were found between the time from baseline testing and differences in scores from baseline to current testing. There was a significant main effect across time between BESS baseline scores and testing scores. Conclusions: Eighty-one percent of participants demonstrated a deficit from their baseline scores on one or more of the assessments, thus failing the concussion battery and giving objective evidence of a possible concussion. When a patient fails an objective assessment used to identify and diagnose a concussion, they are at risk of being removed from all participation. To return to participation, the current recommendation is a symptom free graduated return to play protocol taking about seven days to complete. This may result in significant playing time lost for the athlete

Relationships Between the Performance of Time/Frequency Standards and Navigation/Communication Systems

The relationship between system performance and clock or oscillator performance is discussed. Tradeoffs discussed include: short term stability versus bandwidth requirements; frequency accuracy versus signal acquisition time; flicker of frequency and drift versus resynchronization time; frequency precision versus communications traffic volume; spectral purity versus bit error rate, and frequency standard stability versus frequency selection and adjustability. The benefits and tradeoffs of using precise frequency and time signals are various levels of precision and accuracy are emphasized

On the existence of effective potentials in time-dependent density functional theory

We investigate the existence and properties of effective potentials in time-dependent density functional theory. We outline conditions for a general solution of the corresponding Sturm-Liouville boundary value problems. We define the set of potentials and v-representable densities, give a proof of existence of the effective potentials under certain restrictions, and show the set of v-representable densities to be independent of the interaction.Comment: 13 page

DEVELOPMENT OF VIRTUAL EVENT MARKETING

In the last few years the Pichia pastoris expression system has been gaining more and more interest for the expression of recombinant proteins. Many groups have employed fermentation technology in their investigations because the system is fairly easy to scale up and suitable for the production in the milligram to gram range. A large number of heterologous proteins from different sources has been expressed, but the fermentation process technology has been investigated to a lesser extent. A large number of fermentations are carried out in standard bioreactors that may be insufficiently equipped to meet the demands of high-cell-density fermentations of methylotrophic yeasts. In particular, the lack of on-line methanol analysis leads to fermentation protocols that may impair the optimal expression of the desired products. We have used a commercially available methanol sensor to investigate in detail the effects of supplementary glycerol feeding while maintaining a constant methanol concentration during the induction of a Mut+ strain of Pichia pastoris. Specific glycerol feed rates in the range of 38-4.2 mg × g(exp -1) × h(exp -1) (mg glycerol per gram fresh weight per hour) were investigated. Expression of the recombinant scFv antibody fragment was only observed at specific feed rates below 6 mg × g(exp -1) × h(exp -1). At low specific feed rates, growth was even lower than with methanol as the sole carbon source and the harvest expression level of the scFv was only half of that found in the control fermentation. These results show that glycerol inhibits expression driven by the AOX1 promoter even at extremely limited availability and demonstrate the benefits of on-line methanol control in Pichia fermentation research

The correlation between ovule quality parameters and the seed yield at Cyclamen persicum MILL.

Are there indicators that the seed yield at Cyclamen persicum is predetermined by the quality of ovules? This was the main question of these investigations.The aim of our study was to investigate why only some of the available ovules develop into mature seeds. We surmised that the quality of the ovules played an important role in this. In order to corroborate this theory, we examined specific ovule parameters and their correlation with seed yield.The parameters included the levels of callose in the nucellus, the heterogeneity of embryo sacs, the deviants in callose inclusion and the number of ovules examined by light and fluorescence microscopy.There is still considerable disagreement on the biological significance of the inclusion of callose in ovules. In our study, we were able to show that the inclusion of callose is essential for fertilization in the case of C. persicum. This appears to contradict the findings reported for other plant species, where the inclusion of callose has been evaluated as a sign of ovule degeneration. However, the results of our study clearly demonstrate that seed yield is already determined by the maternal plant during the ovule development phase, i. e. shortly before and at the beginning of anthesis.Some ovule parameters allow predictions to be made about the expected seed yield for the studied genotypes of C. persicum

Diagnostic performance of the specific uptake size index for semi-quantitative analysis of I-123-FP-CIT SPECT: harmonized multi-center research setting versus typical clinical single-camera setting

Introduction: The specific uptake size index (SUSI) of striatal FP-CIT uptake is independent of spatial resolution in the SPECT image, in contrast to the specific binding ratio (SBR). This suggests that the SUSI is particularly appropriate for multi-site/multi-camera settings in which camera-specific effects increase inter-subject variability of spatial resolution. However, the SUSI is sensitive to inter-subject variability of striatum size. Furthermore, it might be more sensitive to errors of the estimate of non-displaceable FP-CIT binding. This study compared SUSI and SBR in the multi-site/multi-camera (MULTI) setting of a prospective multi-center study and in a mono-site/mono-camera (MONO) setting representative of clinical routine. Methods: The MULTI setting included patients with Parkinson’s disease (PD, n = 438) and healthy controls (n = 207) from the Parkinson Progression Marker Initiative. The MONO setting included 122 patients from routine clinical patient care in whom FP-CIT SPECT had been performed with the same double-head SPECT system according to the same acquisition and reconstruction protocol. Patients were categorized as “neurodegenerative” (n = 84) or “non-neurodegenerative” (n = 38) based on follow-up data. FP-CIT SPECTs were stereotactically normalized to MNI space. SUSI and SBR were computed for caudate, putamen, and whole striatum using unilateral ROIs predefined in MNI space. SUSI analysis was repeated in native patient space in the MONO setting. The area (AUC) under the ROC curve for identification of PD/“neurodegenerative” cases was used as performance measure. Results: In both settings, the highest AUC was achieved by the putamen (minimum over both hemispheres), independent of the semi-quantitative method (SUSI or SBR). The putaminal SUSI provided slightly better performance with ROI analysis in MNI space compared to patient space (AUC = 0.969 vs. 0.961, p = 0.129). The SUSI (computed in MNI space) performed slightly better than the SBR in the MULTI setting (AUC = 0.993 vs. 0.991, p = 0. 207) and slightly worse in the MONO setting (AUC = 0.969 vs. AUC = 0.976, p = 0.259). There was a trend toward larger AUC difference between SUSI and SBR in the MULTI setting compared to the MONO setting (p = 0.073). Variability of voxel intensity in the reference region was larger in misclassified cases compared to correctly classified cases for both SUSI and SBR (MULTI setting: p = 0.007 and p = 0.012, respectively). Conclusions: The SUSI is particularly useful in MULTI settings. SPECT images should be stereotactically normalized prior to SUSI analysis. The putaminal SUSI provides better diagnostic performance than the SUSI of the whole striatum. Errors of the estimate of non-displaceable count density in the reference region can cause misclassification by both SUSI and SBR, particularly in borderline cases. These cases might be identified by visual checking FP-CIT uptake in the reference region for particularly high variability