Exploring College Students\u27 Perceptions of College Gun Violence: A Meta-Analysis

College gun violence has been one of our nation’s most forefront issues in recent years. The present meta-analysis reviewed studies reporting college students’ perceptions about school/college gun violence in order to summarize the total effect and direction of these research findings. There were only two studies identified for this research topic: Study A and Study B. Combining the effect sizes from both studies could not be accomplished because there was not enough data from Study A to calculate the correlation coefficient(r) or standardized mean difference (SMD). The summary of the results of the two studies as a metaanalysis was more a descriptive analysis. With the exception of the more conservative study participants, participants in both studies felt the most significant variable in the occurrence of school/college gun violence was the mental health of the individual perpetrator

Identifying Biomagnetic Sources in the Brain by the Maximum Entropy Approach

Magnetoencephalographic (MEG) measurements record magnetic fields generated from neurons while information is being processed in the brain. The inverse problem of identifying sources of biomagnetic fields and deducing their intensities from MEG measurements is ill-posed when the number of field detectors is far less than the number of sources. This problem is less severe if there is already a reasonable prior knowledge in the form of a distribution in the intensity of source activation. In this case the problem of identifying and deducing source intensities may be transformed to one of using the MEG data to update a prior distribution to a posterior distribution. Here we report on some work done using the maximum entropy method (ME) as an updating tool. Specifically, we propose an implementation of the ME method in cases when the prior contain almost no knowledge of source activation. Two examples are studied, in which part of motor cortex is activated with uniform and varying intensities, respectively.Comment: 8 pages, 8 figures. Presented at 25th International Workshop on Bayesian Inference and Maximum Entropy Methods in Science and Engineering, San Jose, CA, USA Aug 7-12, 200

The Impact of Sleep Apnea on Conventional Doppler Indices

AbstractObjectiveTo prospectively explore the impact of obstructive sleep apnea (OSA) on conventional Doppler indices and to identify possible negative prognostic factors for left ventricular diastolic dysfunction. Materials and Methods: All included subjects had overnight polysomnog-raphy. All subjects underwent a comprehensive echocardiography examination to evaluate systolic and diastolic function of the left ventricle. A multiple logistic regression model was created to identify potential negative prognostic factors for left ventricular dysfunction.ResultsA significant decrease in the ratio of early and atrial mitral flow velocity (E/A ratio) in OSA patients was found. Patients with moderate-to-severe OSA had a significant increase in the odds ratio for development of an abnormal E/A ratio (p=0.014, multivariate logistic regression). There was a significant negative correlation between E/A ratio and apnea-hypopnea index (p = 0.01). Non-obese OSA patients and obese-OSA patients carried significantly increased odds ratios for the development of a reduced E/A ratio (p = 0.02 and 0.038, respectively).ConclusionSubjects with OSA had reduced mitral E/A ratios, which implies possible impaired diastolic heart function. Further study to reverse impaired diastolic function via lifestyle modifications and treatment with nasal continuous positive airway pressure or surgery is warranted