103 research outputs found
When Does Information Asymmetry Affect the Cost of Capital?
This paper examines when information asymmetry among investors affects the cost of capital in excess of standard risk factors. When equity markets are perfectly competitive, information asymmetry has no separate effect on the cost of capital. When markets are imperfect, information asymmetry can have a separate effect on firmsâ cost of capital. Consistent with our prediction, we find that information asymmetry has a positive relation with firmsâ cost of capital in excess of standard risk factors when markets are imperfect and no relation when markets approximate perfect competition. Overall, our results show that the degree of market competition is an important conditioning variable to consider when examining the relation between information asymmetry and cost of capital
Assessment of first and second degree relatives of individuals with bipolar disorder shows increased genetic risk scores in both affected relatives and young AtâRisk Individuals
Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/113761/1/ajmgb32344.pd
Demonstrating testâretest reliability of electrophysiological measures for healthy adults in a multisite study of biomarkers of antidepressant treatment response
Growing evidence suggests that loudness dependency of auditory evoked potentials (LDAEP) and resting EEG alpha and theta may be biological markers for predicting response to antidepressants. In spite of this promise, little is known about the joint reliability of these markers, and thus their clinical applicability. New standardized procedures were developed to improve the compatibility of data acquired with different EEG platforms, and used to examine testâretest reliability for the three electrophysiological measures selected for a multisite projectâEstablishing Moderators and Biosignatures of Antidepressant Response for Clinical Care (EMBARC). Thirtyânine healthy controls across four clinical research sites were tested in two sessions separated by about 1 week. Resting EEG (eyesâopen and eyesâclosed conditions) was recorded and LDAEP measured using binaural tones (1000 Hz, 40 ms) at five intensities (60â100 dB SPL). Principal components analysis of current source density waveforms reduced volume conduction and provided referenceâfree measures of resting EEG alpha and N1 dipole activity to tones from auditory cortex. Lowâresolution electromagnetic tomography (LORETA) extracted resting theta current density measures corresponding to rostral anterior cingulate (rACC), which has been implicated in treatment response. There were no significant differences in posterior alpha, N1 dipole, or rACC theta across sessions. Testâretest reliability was .84 for alpha, .87 for N1 dipole, and .70 for theta rACC current density. The demonstration of goodâtoâexcellent reliability for these measures provides a template for future EEG/ERP studies from multiple testing sites, and an important step for evaluating them as biomarkers for predicting treatment response.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/135271/1/psyp12758_am.pdfhttp://deepblue.lib.umich.edu/bitstream/2027.42/135271/2/psyp12758.pdfhttp://deepblue.lib.umich.edu/bitstream/2027.42/135271/3/psyp12758-sup-0001-suppinfo1.pd
The diagnosis of pancreatic mucinous cystic neoplasm and associated adenocarcinoma in males: An eightâinstitution study of 349 patients over 15 years
Peer Reviewedhttps://deepblue.lib.umich.edu/bitstream/2027.42/137278/1/jso24582_am.pdfhttps://deepblue.lib.umich.edu/bitstream/2027.42/137278/2/jso24582.pd
Association of Preoperative Risk Factors With Malignancy in Pancreatic Mucinous Cystic Neoplasms: A Multicenter Study
Pancreatic mucinous cystic neoplasms (MCNs) harbor malignant potential, and current guidelines recommend resection. However, data are limited on preoperative risk factors for malignancy (adenocarcinoma or high-grade dysplasia) occurring in the setting of an MCN
Genome-Wide Association of Bipolar Disorder Suggests an Enrichment of Replicable Associations in Regions near Genes
Although a highly heritable and disabling disease, bipolar disorder's (BD) genetic variants have been challenging to identify. We present new genotype data for 1,190 cases and 401 controls and perform a genome-wide association study including additional samples for a total of 2,191 cases and 1,434 controls. We do not detect genome-wide significant associations for individual loci; however, across all SNPs, we show an association between the power to detect effects calculated from a previous genome-wide association study and evidence for replication (Pâ=â1.5Ă10â7). To demonstrate that this result is not likely to be a false positive, we analyze replication rates in a large meta-analysis of height and show that, in a large enough study, associations replicate as a function of power, approaching a linear relationship. Within BD, SNPs near exons exhibit a greater probability of replication, supporting an enrichment of reproducible associations near functional regions of genes. These results indicate that there is likely common genetic variation associated with BD near exons (±10 kb) that could be identified in larger studies and, further, provide a framework for assessing the potential for replication when combining results from multiple studies
Recommended from our members
Resting EEG Measures Of Brain Arousal In A Multisite Study Of Major Depression
Several studies have found upregulated brain arousal during 15-minute EEG recordings at rest in depressed patients. However, studies based on shorter EEG recording intervals are lacking. Here we aimed to compare measures of brain arousal obtained from 2-minute EEGs at rest under eyes-closed condition in depressed patients and healthy controls in a multisite projectâEstablishing Moderators and Biosignatures of Antidepressant Response for Clinical Care (EMBARC). We expected that depressed patients would show stable and elevated brain arousal relative to controls. Eighty-seven depressed patients and 36 healthy controls from four research sites in the United States were included in the analyses. The Vigilance Algorithm Leipzig (VIGALL) was used for the fully automatic classification of EEG-vigilance stages (indicating arousal states) of 1-second EEG segments; VIGALL-derived measures of brain arousal were calculated. We found that depressed patients scored higher on arousal stability (Z = â2.163, P = .015) and A stages (dominant alpha activity; P = .027) but lower on B1 stages (low-voltage non-alpha activity, P = .008) compared with healthy controls. No significant group differences were observed in Stage B2/3. In summary, we were able to demonstrate stable and elevated brain arousal during brief 2-minute recordings at rest in depressed patients. Results set the stage for examining the value of these measures for predicting clinical response to antidepressants in the entire EMBARC sample and evaluating whether an upregulated brain arousal is particularly characteristic for responders to antidepressants
Recommended from our members
Pretreatment Rostral Anterior Cingulate Cortex Theta Activity In Relation To Symptom Improvement In Depression: A Randomized Clinical Trial
OBJECTIVE To determine whether increased pretreatment rACC theta activity would predict symptom improvement regardless of randomization arm. DESIGN, SETTING, AND PARTICIPANTS A multicenter randomized clinical trial enrolled outpatients without psychosis and with chronic or recurrent MDD between July 29, 2011, and December 15, 2015 (Establishing Moderators and Biosignatures of Antidepressant Response for Clinical Care [EMBARC]). Patients were consecutively recruited from 4 university hospitals: 634 patients were screened, 296 were randomized to receive sertraline hydrochloride or placebo, 266 had electroencephalographic (EEG) recordings, and 248 had usable EEG data. Resting EEG data were recorded at baseline and 1 week after trial onset, and rACC theta activity was extracted using source localization. Intent-to-treat analysis was conducted. Data analysis was performed from October 7, 2016, to January 19, 2018. INTERVENTIONS An 8-week course of sertraline or placebo. MAIN OUTCOMES AND MEASURES The 17-item Hamilton Rating Scale for Depression score (assessed at baseline and weeks 1, 2, 3, 4, 6, and 8). RESULTS The 248 participants (160 [64.5%] women, 88 [35.5%] men) with usable EEG data had a mean (SD) age of 36.75 (13.15) years. Higher rACC theta activity at both baseline (b=â1.05; 95% CI, â1.77 to â0.34; P = .004) and week 1 (b=â0.83; 95% CI, â1.60 to â0.06; P < .04) predicted greater depressive symptom improvement, even when controlling for clinical and demographic variables previously linked with treatment outcome. These effects were not moderated by treatment arm. The rACC theta marker, in combination with clinical and demographic variables, accounted for an estimated 39.6% of the variance in symptom change (with 8.5% of the variance uniquely attributable to the rACC theta marker). CONCLUSIONS AND RELEVANCE Increased pretreatment rACC theta activity represents a nonspecific prognostic marker of treatment outcome. This is the first study to date to demonstrate that rACC theta activity has incremental predictive validity
- âŠ