Evidence for a Spoken Word Lexicon in the Auditory Ventral Stream.

The existence of a neural representation for whole words (i.e., a lexicon) is a common feature of many models of speech processing. Prior studies have provided evidence for a visual lexicon containing representations of whole written words in an area of the ventral visual stream known as the visual word form area. Similar experimental support for an auditory lexicon containing representations of spoken words has yet to be shown. Using functional magnetic resonance imaging rapid adaptation techniques, we provide evidence for an auditory lexicon in the auditory word form area in the human left anterior superior temporal gyrus that contains representations highly selective for individual spoken words. Furthermore, we show that familiarization with novel auditory words sharpens the selectivity of their representations in the auditory word form area. These findings reveal strong parallels in how the brain represents written and spoken words, showing convergent processing strategies across modalities in the visual and auditory ventral streams.

The Asymmetric Impact of COVID-19: A Novel Approach to Quantifying Financial Distress across Industries.

This paper assesses corporate financial distress in terms of liquidity and risk of insolvency due to the COVID-19 pandemic. We develop a novel multivariate approach to obtain monthly data on industry turnover, exploiting real time data to capture the atypical character of industry-specific disturbances. By combining the estimated set of industry revenue shocks with pre-pandemic financial statements, we quantify the impact of the pandemic on the risk of insolvency in the EU non-financial corporate sector. Our definition of risk of insolvency takes into account not only the equity position of firms, but also risks relating to overindebtedness. The analysis controls for firms that were financially vulnerable already before the pandemic, thus being prone to become at risk of insolvency also in absence of the COVID-19 turmoil. We find that, for the EU as a whole, 25% of firms exhausted their liquidity buffers by the end of 2021 (a practical cut-off date of the analysis, not an assumed end of the pandemic). Furthermore, 10% of firms which were viable before the pandemic, appear to have shifted into risk of insolvency as a result of the COVID-19 crisis. The magnification of financial vulnerability in the hardest-hit industries mainly occurs among firms with no legacy issues, i.e. firms with positive profitability pre-pandemic. A similar finding is reported for some of the hardest-hit countries, such as Italy and Spain. In other countries, such as Germany or Greece, the magnification of financial vulnerability mainly occurs among firms with negative profitability pre-pandemic.

The Importance of Cognitive Domains and the Returns to Schooling in South Africa: Evidence from Two Labor Surveys.

Numerous studies have considered the important role of cognition in estimating the returns to schooling. How cognitive abilities affect schooling may have important policy implications, especially in developing countries during periods of increasing educational attainment. Using two longitudinal labor surveys that collect direct proxy measures of cognitive skills, we study the importance of specific cognitive domains for the returns to schooling in two samples. We instrument for schooling levels and we find that each additional year of schooling leads to an increase in earnings by approximately 18-20 percent. The estimated effect sizes-based on the two-stage least squares estimates-are above the corresponding ordinary least squares estimates. Furthermore, we estimate and demonstrate the importance of specific cognitive domains in the classical Mincer equation. We find that executive functioning skills (i.e., memory and orientation) are important drivers of earnings in the rural sample, whereas higher-order cognitive skills (i.e., numeracy) are more important for determining earnings in the urban sample. Although numeracy is tested in both samples, it is only a statistically significant predictor of earnings in the urban sample.

Ventricular arrhythmia risk prediction in repaired Tetralogy of Fallot using personalized computational cardiac models.

BACKGROUND: Adults with repaired tetralogy of Fallot (rTOF) are at increased risk for ventricular tachycardia (VT) due to fibrotic remodeling of the myocardium. However, the current clinical guidelines for VT risk stratification and subsequent implantable cardioverter-defibrillator deployment for primary prevention of sudden cardiac death in rTOF remain inadequate. OBJECTIVE: The purpose of this study was to determine the feasibility of using an rTOF-specific virtual-heart approach to identify patients stratified incorrectly as being at low VT risk by current clinical criteria. METHODS: This multicenter retrospective pilot study included 7 adult rTOF patients who were considered low risk for VT based on clinical criteria. Patient-specific computational heart models were generated from late gadolinium enhanced magnetic resonance imaging (LGE-MRI), incorporating the individual distribution of rTOF fibrotic remodeling in both ventricles. Simulations of rapid pacing determined VT inducibility. Model creation and simulations were performed by operators blinded to clinical outcome. RESULTS: Two patients in the study experienced clinical VT. The virtual hearts constructed from LGE-MRI scans of 7 rTOF patients correctly predicted reentrant VT in the models from VT-positive patients and no arrhythmia in those from VT-negative patients. There were no statistically significant differences in clinical criteria commonly used to assess VT risk, including QRS duration and age, between patients who did and those who did not experience clinical VT. CONCLUSION: This study demonstrates the feasibility of image-based virtual-heart modeling in patients with congenital heart disease and structurally abnormal hearts. It highlights the potential of the methodology to improve VT risk stratification in patients with rTOF.

Characterizing Conduction Channels in Postinfarction Patients Using a Personalized Virtual Heart.

Patients with myocardial infarction have an abundance of conduction channels (CC); however, only a small subset of these CCs sustain ventricular tachycardia (VT). Identifying these critical CCs (CCCs) in the clinic so that they can be targeted by ablation remains a significant challenge. The objective of this study is to use a personalized virtual-heart approach to conduct a three-dimensional (3D) assessment of CCCs sustaining VTs of different morphologies in these patients, to investigate their 3D structural features, and to determine the optimal ablation strategy for each VT. To achieve these goals, ventricular models were constructed from contrast enhanced magnetic resonance imagings of six postinfarction patients. Rapid pacing induced VTs in each model. CCCs that sustained different VT morphologies were identified. CCCs' 3D structure and type and the resulting rotational electrical activity were examined. Ablation was performed at the optimal part of each CCC, aiming to terminate each VT with a minimal lesion size. Predicted ablation locations were compared to clinical. Analyzing the simulation results, we found that the observed VTs in each patient model were sustained by a limited number (2.7 ± 1.2) of CCCs. Further, we identified three types of CCCs sustaining VTs: I-type and T-type channels, with all channel branches bounded by scar, and functional reentry channels, which were fully or partially bounded by conduction block surfaces. The different types of CCCs accounted for 43.8, 18.8, and 37.4% of all CCCs, respectively. The mean narrowest width of CCCs or a branch of CCC was 9.7 ± 3.6 mm. Ablation of the narrowest part of each CCC was sufficient to terminate VT. Our results demonstrate that a personalized virtual-heart approach can determine the possible VT morphologies in each patient and identify the CCCs that sustain reentry. The approach can aid clinicians in identifying accurately the optimal VT ablation targets in postinfarction patients.

Sensitivity of Ablation Targets Prediction to Electrophysiological Parameter Variability in Image-Based Computational Models of Ventricular Tachycardia in Post-infarction Patients.

Ventricular tachycardia (VT), which could lead to sudden cardiac death, occurs frequently in patients with myocardial infarction. Computational modeling has emerged as a powerful platform for the non-invasive investigation of lethal heart rhythm disorders in post-infarction patients and for guiding patient VT ablation. However, it remains unclear how VT dynamics and predicted ablation targets are influenced by inter-patient variability in action potential duration (APD) and conduction velocity (CV). The goal of this study was to systematically assess the effect of changes in the electrophysiological parameters on the induced VTs and predicted ablation targets in personalized models of post-infarction hearts. Simulations were conducted in 5 patient-specific left ventricular models reconstructed from late gadolinium-enhanced magnetic resonance imaging scans. We comprehensively characterized all possible pre-ablation and post-ablation VTs in simulations conducted with either an "average human VT"-based electrophysiological representation (i.e., EPavg) or with ±10% APD or CV (i.e., EPvar); additional simulations were also executed in some models for an extended range of these parameters. The results showed that: (1) a subset of reentries (76.2-100%, depending on EP parameter set) conducted with ±10% APD/CV was observed in approximately the same locations as reentries observed in EPavg cases; (2) emergent VTs could be induced sometimes after ablation in EPavg models, and these emergent VTs often corresponded to the pre-ablation reentries in simulations with EPvar parameter sets. These findings demonstrate that the VT ablation target uncertainty in patient-specific ventricular models with an average representation of VT-remodeled electrophysiology is relatively low and the ablation targets stable, as the localization of the induced VTs was primarily driven by the remodeled structural substrate. Thus, personalized ventricular modeling with an average representation of infarct-remodeled electrophysiology may uncover most targets for VT ablation.

Short-Run Health Consequences of Retirement and Pension Benefits: Evidence from China.

This paper examines the impact of the New Rural Pension Scheme (NRPS) in China. Exploiting the staggered implementation of an NRPS policy expansion that began in 2009, we use a difference-in-difference approach to study the effects of the introduction of pension benefits on the health status, health behaviors, and healthcare utilization of rural Chinese adults age 60 and above. The results point to three main conclusions. First, in addition to improvements in self-reported health, older adults with access to the pension program experienced significant improvements in several important measures of health, including mobility, self-care, usual activities, and vision. Second, regarding the functional domains of mobility and self-care, we found that the females in the study group led in improvements over their male counterparts. Third, in our search for the mechanisms that drive positive retirement program results, we find evidence that changes in individual health behaviors, such as a reduction in drinking and smoking, and improved sleep habits, play an important role. Our findings point to the potential benefits of retirement programs resulting from social spillover effects. In addition, these programs may lessen the morbidity burden among the retired population.

Computational Identification of Ventricular Arrhythmia Risk in Pediatric Myocarditis.

Children with myocarditis have increased risk of ventricular tachycardia (VT) due to myocardial inflammation and remodeling. There is currently no accepted method for VT risk stratification in this population. We hypothesized that personalized models developed from cardiac late gadolinium enhancement magnetic resonance imaging (LGE-MRI) could determine VT risk in patients with myocarditis using a previously-validated protocol. Personalized three-dimensional computational cardiac models were reconstructed from LGE-MRI scans of 12 patients diagnosed with myocarditis. Four patients with clinical VT and eight patients without VT were included in this retrospective analysis. In each model, we incorporated a personalized spatial distribution of fibrosis and myocardial fiber orientations. Then, VT inducibility was assessed in each model by pacing rapidly from 26 sites distributed throughout both ventricles. Sustained reentrant VT was induced from multiple pacing sites in all patients with clinical VT. In the eight patients without clinical VT, we were unable to induce sustained reentry in our simulations using rapid ventricular pacing. Application of our non-invasive approach in children with myocarditis has the potential to correctly identify those at risk for developing VT.

Virtual electrophysiological study as a tool for evaluating efficacy of MRI techniques in predicting adverse arrhythmic events in ischemic patients.

Myocardial infarct (MI) related indices determined by late gadolinium enhancement (LGE) MRI have been widely investigated in determining patients suitable for implantable cardiovascular-defibrillator (ICD) therapy to complement left ventricular ejection fraction (LV EF). In comparison to LGE-MRI using inversion-recovery fast-gradient-echo (IR-FGRE), T1 mapping techniques, such as multi contrast late enhancement (MCLE), have been shown to provide more quantitative and reproducible estimates of infarct regions. The objective of this study is to use individualized heart computer models in determining the efficacy of IR-FGRE and MCLE techniques in predicting the occurrence of post-MI ventricular tachycardia (VT). Twenty-seven patients with MI underwent LGE-MRI using IR-FGRE and MCLE prior to ICD implantation and were followed up for 6-46 months. Individualized image-based computational models were built separately for each imaging technique; simulations of propensity to VT were conducted with each model. The imaging methods were evaluated by comparing simulated inducibility of VT to clinical outcome (appropriate ICD therapy) in patients. Twelve patients had at least one appropriate ICD therapy for VT at follow-up. For both MCLE and IR-FGRE, the outcomes of the simulations of VT were significantly associated with the events of appropriate ICD therapy. This indicates that, as compared to conventional measurements such as LV EF, the simulations of VT corresponding to both MCLE and IR-FGRE were more sensitive in predicting appropriate ICD therapy in post-MI patients.

Optimal contrast-enhanced MRI image thresholding for accurate prediction of ventricular tachycardia using ex-vivo high resolution models.

Patient specific models created from contrast-enhanced (i.e. late-gadolinium, LGE) MRI images can be used for prediction of reentry location and clinical ablation planning. However, there is still a need for direct and systematic comparison between characteristics of ventricular tachycardia (VT) morphologies predicted in computational models and those acquired in clinical or experimental protocols. In this study, we aimed to: 1) assess the differences in VT morphologies predicted by modeling and recorded in experiments in terms of patterns and location of reentries, earliest and latest activation sites, and cycle lengths; and 2) define the optimal range of infarct tissue threshold values which provide best match between simulation and experimental results. To achieve these goals, we utilized LGE-MRI images from 4 swine hearts with inducible monomorphic VT. The images were segmented to identify non-infarcted myocardium, semi viable gray zone (GZ), and core scar based on pixel intensity. Several models were reconstructed from each LGE-MRI scan, with voxels of intensity between that of non-infarcted myocardium and 20-50% of the maximum intensity (in 10% increments) in the infarct region classified as GZ. VT induction was simulated in each model. Our simulation results showed that using GZ intensity thresholds of 20% or 30% resulted in the best match of simulated propagation patterns and reentry locations with those from the experiment. Overall, we matched 70% (7/10) morphologies for all the hearts. Our simulation shows that MRI-based computational models of hearts with myocardial infarction can accurately reproduce the majority of experimentally recorded post-infarction VTs.

Personalized Imaging and Modeling Strategies for Arrhythmia Prevention and Therapy.

The goal of this article is to review advances in computational modeling of the heart, with a focus on recent non-invasive clinical imaging- and simulation-based strategies aimed at improving the diagnosis and treatment of patients with arrhythmias and structural heart disease. Following a brief overview of the field of computational cardiology, we present recent applications of the personalized virtual-heart approach in predicting the optimal targets for infarct-related ventricular tachycardia and atrial fibrillation ablation, and in determining risk of sudden cardiac death in myocardial infarction patients. The hope is that with such models at the patient bedside, therapies could be improved, invasiveness of diagnostic procedures minimized, and health-care costs reduced.

Personalized virtual-heart technology for guiding the ablation of infarct-related ventricular tachycardia.

Ventricular tachycardia (VT), which can lead to sudden cardiac death, occurs frequently in patients with myocardial infarction. Catheter-based radiofrequency ablation of cardiac tissue has achieved only modest efficacy, owing to the inaccurate identification of ablation targets by current electrical mapping techniques, which can lead to extensive lesions and to a prolonged, poorly tolerated procedure. Here we show that personalized virtual-heart technology based on cardiac imaging and computational modelling can identify optimal infarct-related VT ablation targets in retrospective animal (5 swine) and human studies (21 patients) and in a prospective feasibility study (5 patients). We first assessed in retrospective studies (one of which included a proportion of clinical images with artifacts) the capability of the technology to determine the minimum-size ablation targets for eradicating all VTs. In the prospective study, VT sites predicted by the technology were targeted directly, without relying on prior electrical mapping. The approach could improve infarct-related VT ablation guidance, where accurate identification of patient-specific optimal targets could be achieved on a personalized virtual heart prior to the clinical procedure.

Non-perforation tension pneumoperitoneum resulting from primary non-aerobic bacterial peritonitis in a previously healthy middle-aged man: a case report.

BACKGROUND: Tension pneumoperitoneum is a rare surgical emergency in which free intraperitoneal gas accumulates under pressure. The known sources of free gas are perforated hollow viscera. We believe this is the first published case of a tension non-perforation pneumoperitoneum secondary to anaerobic gas production. This occurred in a background of primary non-aerobic bacterial peritonitis, which developed in an immunocompetent adult man. CASE PRESENTATION: A previously healthy 45-year-old Bulgarian man presented with a 3-week history of abdominal pain. He displayed signs of shock, peritonitis, and abdominal compartment syndrome. A plain abdominal X-ray showed the pathognomonic "saddlebag sign" with his liver displaced downwards and medially. An emergency laparotomy released pressurized gas, accompanied by 3100 mL of foamy pus. A sudden hemodynamic deterioration occurred soon after decompression. The sources of infection and tension pneumoperitoneum were not found. The peritoneal exudate sample did not recover aerobes. A laparostomy was created and three planned re-operations were performed. During the second re-laparotomy we placed an intraperitoneal silo and his abdomen was closed with skin sutures. Definitive fascial closure was achieved through separation of his two rectus muscles from their posterior sheaths. He was discharged in good health on the 25th postoperative day. CONCLUSIONS: Our case provides evidence supporting the theory that anaerobic infection may underlie the etiology of tension pneumoperitoneum. Prior to decompressive laparotomy the patient should receive an intravenous volume bolus to compensate for possible hypotension. If laparostomy leads to lateralization of the rectus muscles with a gap of 6 cm or less, the posterior part of the components separation technique is effective in achieving fascial closure. We present an original classification of tension pneumoperitoneum defining it as primary or secondary.

[Non-perforation tensionpneumoperitoneum resulting from primary non-aerobic bacterial peritonitisin a previously healthy middle-aged man: A case report].

Background: Tension pneumoperitoneumis a rare surgical emergency in which free intra-peritoneal gas accumulates under pressure. The known sources of free gas are perforated hollow viscera. We believe this is the first published case of atension non-perforation pneumoperitoneum secondary to anaerobic gas production. This occurred in a background of primary non-aerobic bacterial peritonitis, which developed in an immunocompetent adult male. Case presentation: A previously healthy 45-year-old Bulgarian male presented with a 3-week history of abdominal pain. He displayed signs of shock, peritonitis, and abdominal compartment syndrome. A plain abdominal X-ray showed thepathognomonic "saddlebag sign" with the liver displaced downwards and medially. An emergency laparotomy released pressurized gas, accompanied by 3100 mL of foamy pus. A sudden haemodynamic deterioration occurred soon after decompression. The sources of infection and tension pneumoperitoneum were not found. The peritoneal exudate sample did not recover aerobes. A laparostomy was created and three planned re-laparotomies were performed. During the second re-operation we placed an intraperitoneal silo and the abdomen was closed with skin sutures. Definitive fascial closure was achieved through separation of the two rectus muscles from their posterior sheaths. The patient was discharged in good healthon the 25th postoperative day. Conclusion: Our case provides evidence supporting the theory that anaerobic infection may underlie the etiology of tension pmeumoperitoneum. Prior to decompressive laparotomy the patient should receive an intravenous volume bolus to compensate for possible hypotension. If laparostomy leads to lateralization of the rectus muscles with a gap of 6 cm or less, the posterior part of the components separation technique is effective in achieving fascial closure. We present an original classification of tension pneumoperitoneum defining it as primary or secondary.

Role of the ribose-specific marker furfuryl-amine in the formation of aroma active 1-(furan-2-ylmethyl)-1H-pyrrole (or furfuryl-pyrrole) derivatives.

Furfuryl-pyrroles possess a diverse range of organoleptic properties described as roasted, chocolaty, green, horseradish-like, and mushroom-like and are detected in various foods such as coffee, chocolate, popcorn, and roasted chicken. Although their origin in food was attributed to furfuryl-amine, the latter has not been detected so far in Maillard model systems or in foods. In this study, furfuryl-amine was shown to be formed specifically from ribose through nitrogen atom transfer from the α-amino group of any amino acid. Such a transfer can be achieved through decarboxylation of the Schiff base adduct and isomerization followed by hydrolysis. Through the use of (15)Nα-lysine it was revealed that only the (15)Nα nitrogen atom was incorporated into its structure, indicating a specific role for the carboxylate moiety in the mechanism of its formation. Furthermore, isotope labeling studies have indicated that furfuryl-pyrrole derivatives can be formed by the interaction of 2 mol of furfuryl-amine with 3-deoxyribosone followed by dehydration and cyclization to form 1-(furan-2-yl)-N-{[1-(furan-2-ylmethyl)-1H-pyrrol-2-yl]methylidene}methanamine. After hydrolysis, this intermediate can generate furfuryl-formyl-pyrrole, furfuryl-pyrrole carboxylic acid, and furfuryl-pyrrole. In this study, the furfuryl-amine derivatives were also detected in different coffee beans after pyrolysis and analysis by GC-MS. The potential of these compounds to form in aqueous model systems at a temperature of 120 °C was also demonstrated.

Thermal decomposition of 5-(hydroxymethyl)-2-furaldehyde (HMF) and its further transformations in the presence of glycine.

Thermal decomposition of HMF has been so far studied indirectly through carbohydrate degradation reactions assuming HMF as the main product. Such studies, however, do not necessarily generate relevant information on HMF decomposition because many other products are generated simultaneously. Direct thermal decomposition using different concentrations of HMF in silica gel was studied using pyrolysis-GC-MS. Undiluted HMF generated four peaks corresponding to 5-methylfurfural, 2,5-furandicarboxaldehdye, HMF, and a major unknown peak at retention time of 20.73 min. The diluted HMF in silica gel (15-fold) generated only the first three peaks. The generation of the unknown peak was dependent on the concentration of HMF, indicating the possibility of a dimeric structure; furthermore, when HMF was generated from [U-13C6]glucose in the reaction mixture, the highest mass in the spectrum of the unknown peak showed the incorporation of 11 carbon atoms from the glucose. Thermal decomposition studies of HMF have also indicated that in the absence of amino acids it can mainly dimerize and the initially formed dimer can degrade to generate 5-methylfurfural and 2,5-furandicarboxaldehyde. On the other hand, thermal degradation of HMF in the presence of glycine generated Schiff base adducts of HMF, 5-methylfurfural, and 2,5-furandicarboxaldehdye in addition to 2-acetyl-5-methylfuran and a newly discovered adduct, 5-[(dimethylamino)methyl]-2-furanmethanol.

Reversible and covalent binding of 5-(hydroxymethyl)-2-furaldehyde (HMF) with lysine and selected amino acids.

The chemical reactivity of 5-(hydroxymethyl)-2-furaldehyde (HMF) with lysine, glycine, and proline was studied using isotope labeling technique. To confirm the formation of HMF adducts in glucose amino acid model systems, a useful strategy was developed in which products simultaneously possessing six glucose (HMF moiety) and any number of amino acid carbon atoms in addition to nitrogen were targeted using specifically labeled precursors such as [(15)N(α)]lysine·2HCl, [(15)N(ε)]lysine·2HCl, [U-(13)C(6)]lysine·2HCl, [(13)C(6)]lysine·2HCl, and [U-(13)C(6)]glucose in the case of lysine model system. In addition, model systems containing HMF and amino acids were also studied to confirm specific adduct formation. Complete labeling studies along with structural analysis using appropriate synthetic precursors such as HMF Schiff base adducts of piperidine and glycine have indicated that HMF generated in the glucose/amino acid model systems initially forms a Schiff base adduct that can undergo decarboxylation through an oxazolidin-5-one intermediate and form two isomeric decarboxylated Schiff bases. Unlike the Schiff bases resulting from primary amines or amino acids such as glycine or lysine, those resulting from secondary amino acids such as proline or secondary amines such as piperidine can further undergo vinylogous Amadori rearrangement, forming N-substituted 5-(aminomethyl)furan-2-carbaldehyde derivatives.

Formation of Pent-4-en-1-amine, the counterpart of acrylamide from lysine and its conversion into piperidine in lysine/glucose reaction mixtures.

Isotope labeling studies performed using lysine/glucose model systems have indicated that lysine can generate piperidine, a reactive amine capable of undergoing Maillard type interactions. Two possible mechanisms were identified for the formation of piperidine: one arising through decarboxylation of lysine alone to generate cadaverine (1,5-diaminopentane) followed by deamination to form pent-4-en-1-amine which in turn can cyclize into piperidine where both Nepsilon and Nalpha atoms of lysine can be equally involved in its generation due to the symmetrical nature of the precursor diamine. On the other hand, in the presence of sugars, lysine, similarly to asparagine and phenylalanine, can undergo carbonyl-assisted decarboxylative deamination reaction to generate pent-4-en-1-amine, the counterpart of acrylamide. The pent-4-en-1-amine can then cyclize to form piperidine through the Nepsilon atom of lysine. To confirm the formation of pent-4-en-1-amine in the lysine/glucose model system, a useful strategy based on Py-GC/MS analysis was developed using isotope labeling technique to identify sugar adducts of pent-4-en-1-amine. Products simultaneously possessing five lysine carbon atoms (C2'-C6') and the Nepsilon-amino group from lysine in addition to glucose carbon atoms were targeted using specifically labeled precursors such as [(15)Nalpha]lysine.2HCl, [(15)Nepsilon]lysine.2HCl, [U-(13)C(6)]lysine.2HCl, [(13)C-6]lysine.2HCl and [U-(13)C(6)]glucose. The complete labeling studies along with structural analysis using synthetic and other available precursors have shown the presence of a peak that satisfies the above criteria, and the peak was tentatively identified as N-(5-methylfuran-2-yl)methylidene]penta-1,3-dien-1-amine incorporating pent-4-en-1-amine in its structure.

A motor imagery-based online interactive brain-controlled switch: paradigm development and preliminary test.

OBJECTIVE: To develop a practical motor imagery-based brain-controlled switch as functional as a real-world switch that is reliable with a minimal false positive operation rate and convenient for users without the need of attention to the switch during a 'No Control' state (when not to activate the switch). METHODS: Four healthy volunteers were instructed to perform an intended motor imagery task following an external sync signal in order to turn on a virtual switch provided on a computer screen. No specific mental task was required during the 'No Control' state. The beta band event-related frequency power (event-related desynchronization or ERD) from a single EEG Laplacian channel was monitored online in real-time. The computer continuously monitored the relative ERD power level until it exceeded a pre-set threshold and turned on the virtual switch. RESULTS: Subject 1 achieved lowest average false positive rate of 0.4+/-0.9% in a five-session online study during the entire 'No Control' state, whereby the subject required 6.8+/-0.6 s of active urging time or total response time of 20.5+/-1.9 s to perform repeated attempts in order to turn on the switch in the online interactive switch operation. The average false positive rate among four subjects was 0.8+/-0.4% with average active urging time of 12.3+/-4.4 s or average response time of 36.9+/-13.0 s. Offline analysis from subject 2 shows that the overall performance from 10-fold cross-validation was 96.2% with 3 consecutive epoch averaging, which was further improved to 99.0% by computationally intensive methods. CONCLUSIONS: The novel design of the brain-controlled switch using the ERD feature associated with motor imagery achieved minimal false positive rate with a reasonable active urging time or response time to activate the switch. SIGNIFICANCE: The reliability and convenience of the developed brain-controlled switch may extend current brain-computer interface capacities in practical communication and control applications.

Economic costs of diabetes in the US in 2002.

OBJECTIVE: Diabetes is the fifth leading cause of death by disease in the U.S. Diabetes also contributes to higher rates of morbidity-people with diabetes are at higher risk for heart disease, blindness, kidney failure, extremity amputations, and other chronic conditions. The objectives of this study were 1). to estimate the direct medical and indirect productivity-related costs attributable to diabetes and 2). to calculate and compare the total and per capita medical expenditures for people with and without diabetes. RESEARCH DESIGN AND METHODS: Medical expenditures were estimated for the U.S. population with and without diabetes in 2002 by sex, age, race/ethnicity, type of medical condition, and health care setting. Health care use and total health care expenditures attributable to diabetes were estimated using etiological fractions, calculated based on national health care survey data. The value of lost productivity attributable to diabetes was also estimated based on estimates of lost workdays, restricted activity days, prevalence of permanent disability, and mortality attributable to diabetes. RESULTS-Direct medical and indirect expenditures attributable to diabetes in 2002 were estimated at 132 billion US dollars. Direct medical expenditures alone totaled 91.8 billion US dollars and comprised 23.2 billion US dollars for diabetes care, 24.6 billion US dollars for chronic complications attributable to diabetes, and 44.1 billion US dollars for excess prevalence of general medical conditions. Inpatient days (43.9%), nursing home care (15.1%), and office visits (10.9%) constituted the major expenditure groups by service settings. In addition, 51.8% of direct medical expenditures were incurred by people >65 years old. Attributable indirect expenditures resulting from lost workdays, restricted activity days, mortality, and permanent disability due to diabetes totaled 39.8 billion US dollars. U.S. health expenditures for the health care components included in the study totaled 865 billion US dollars, of which 160 billion US dollars was incurred by people with diabetes. Per capita medical expenditures totaled 13243 US dollars for people with diabetes and 2560 US dollars for people without diabetes. When adjusting for differences in age, sex, and race/ethnicity between the population with and without diabetes, people with diabetes had medical expenditures that were approximately 2.4 times higher than expenditures that would be incurred by the same group in the absence of diabetes. CONCLUSIONS: The estimated 132 billion US dollars cost likely underestimates the true burden of diabetes because it omits intangibles, such as pain and suffering, care provided by nonpaid caregivers, and several areas of health care spending where people with diabetes probably use services at higher rates than people without diabetes (e.g., dental care, optometry care, and the use of licensed dietitians). In addition, the cost estimate excludes undiagnosed cases of diabetes. Health care spending in 2002 for people with diabetes is more than double what spending would be without diabetes. Diabetes imposes a substantial cost burden to society and, in particular, to those individuals with diabetes and their families. Eliminating or reducing the health problems caused by diabetes through factors such as better access to preventive care, more widespread diagnosis, more intensive disease management, and the advent of new medical technologies could significantly improve the quality of life for people with diabetes and their families while at the same time potentially reducing national expenditures for health care services and increasing productivity in the U.S. economy.