77 results on '"Kothare P"'
Search Results
2. Pitch corrections occur in natural speech and are abnormal in patients with Alzheimer's disease
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Subrahmanya, Anantajit, Ranasinghe, Kamalini G, Kothare, Hardik, Raharjo, Inez, Kim, Kwang S, Houde, John F, and Nagarajan, Srikantan S
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Biological Psychology ,Cognitive and Computational Psychology ,Psychology ,Alzheimer's Disease ,Behavioral and Social Science ,Neurodegenerative ,Acquired Cognitive Impairment ,Alzheimer's Disease including Alzheimer's Disease Related Dementias (AD/ADRD) ,Aging ,Neurosciences ,Clinical Research ,Dementia ,Brain Disorders ,Neurological ,speech production ,speech perception ,speech control ,auditory feedback ,Alzheimer's disease ,Cognitive Sciences ,Experimental Psychology ,Biological psychology ,Cognitive and computational psychology - Abstract
Past studies have explored formant centering, a corrective behavior of convergence over the duration of an utterance toward the formants of a putative target vowel. In this study, we establish the existence of a similar centering phenomenon for pitch in healthy elderly controls and examine how such corrective behavior is altered in Alzheimer's Disease (AD). We found the pitch centering response in healthy elderly was similar when correcting pitch errors below and above the target (median) pitch. In contrast, patients with AD showed an asymmetry with a larger correction for the pitch errors below the target phonation than above the target phonation. These findings indicate that pitch centering is a robust compensation behavior in human speech. Our findings also explore the potential impacts on pitch centering from neurodegenerative processes impacting speech in AD.
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- 2024
3. Impaired Speaking-Induced Suppression in Alzheimer’s Disease
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Kim, Kyunghee X, Dale, Corby L, Ranasinghe, Kamalini G, Kothare, Hardik, Beagle, Alexander J, Lerner, Hannah, Mizuiri, Danielle, Gorno-Tempini, Maria Luisa, Vossel, Keith, Nagarajan, Srikantan S, and Houde, John F
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Biomedical and Clinical Sciences ,Linguistics ,Allied Health and Rehabilitation Science ,Clinical Sciences ,Health Sciences ,Language ,Communication and Culture ,Psychology ,Brain Disorders ,Alzheimer's Disease including Alzheimer's Disease Related Dementias (AD/ADRD) ,Acquired Cognitive Impairment ,Alzheimer's Disease ,Neurodegenerative ,Neurosciences ,Behavioral and Social Science ,Aging ,Dementia ,2.1 Biological and endogenous factors ,Neurological ,Humans ,Female ,Middle Aged ,Alzheimer Disease ,Neurodegenerative Diseases ,Speech ,Auditory Perception ,Auditory Cortex ,speaking-induced suppression ,Alzheimer's disease ,state feedback control model ,efference copy ,magnetoencephalography ,Alzheimer’s disease - Abstract
Alzheimer's disease (AD) is a neurodegenerative disease involving cognitive impairment and abnormalities in speech and language. Here, we examine how AD affects the fidelity of auditory feedback predictions during speaking. We focus on the phenomenon of speaking-induced suppression (SIS), the auditory cortical responses' suppression during auditory feedback processing. SIS is determined by subtracting the magnitude of auditory cortical responses during speaking from listening to playback of the same speech. Our state feedback control (SFC) model of speech motor control explains SIS as arising from the onset of auditory feedback matching a prediction of that feedback onset during speaking, a prediction that is absent during passive listening to playback of the auditory feedback. Our model hypothesizes that the auditory cortical response to auditory feedback reflects the mismatch with the prediction: small during speaking, large during listening, with the difference being SIS. Normally, during speaking, auditory feedback matches its predictions, then SIS will be large. Any reductions in SIS will indicate inaccuracy in auditory feedback prediction not matching the actual feedback. We investigated SIS in AD patients [n = 20; mean (SD) age, 60.77 (10.04); female (%), 55.00] and healthy controls [n = 12; mean (SD) age, 63.68 (6.07); female (%), 83.33] through magnetoencephalography (MEG)-based functional imaging. We found a significant reduction in SIS at ∼100 ms in AD patients compared with healthy controls (linear mixed effects model, F (1,57.5) = 6.849, p = 0.011). The results suggest that AD patients generate inaccurate auditory feedback predictions, contributing to abnormalities in AD speech.
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- 2023
4. Enhanced Multi-Objective A* with Partial Expansion
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Kothare, Valmiki, Ren, Zhongqiang, Rathinam, Sivakumar, and Choset, Howie
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Mathematics - Optimization and Control ,Computer Science - Artificial Intelligence ,I.2.8 - Abstract
The Multi-Objective Shortest Path Problem (MO-SPP), typically posed on a graph, determines a set of paths from a start vertex to a destination vertex while optimizing multiple objectives. In general, there does not exist a single solution path that can simultaneously optimize all the objectives and the problem thus seeks to find a set of so-called Pareto-optimal solutions. To address this problem, several Multi-Objective A* (MOA*) algorithms were recently developed to quickly compute solutions with quality guarantees. However, these MOA* algorithms often suffer from high memory usage, especially when the branching factor (i.e. the number of neighbors of any vertex) of the graph is large. This work thus aims at reducing the high memory consumption of MOA* with little increase in the runtime. By generalizing and unifying several single- and multi-objective search algorithms, we develop the Runtime and Memory Efficient MOA* (RME-MOA*) approach, which can balance between runtime and memory efficiency by tuning two user-defined hyper-parameters., Comment: 8 pages, 4 figures
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- 2022
5. Enhancing Ventilation of Enclosed Spaces Using CFD: Part 2: Ventilation of Low Occupancy Rooms of IIT Bombay
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Kothare, N. S., Tamboli, N. K., Murallidharan, J. S., Singh, A., Kumaraswamy, G., and Sinha, K.
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- 2024
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6. Highlights From the Annual Meeting of the American Epilepsy Society 2022
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Valencia, Ignacio, Alexander, Allyson L, Andrade, Danielle M, Arevalo-Astrada, Miguel, Rubiños, Clio, Auer, Nancy, Bainbridge, Jacquelyn L, Baxendale, Sallie A, Bartolomei, Fabrice, Becker, Danielle A, Berg, Anne T, Bernasconi, Andrea, Bernasconi, Neda, Bernhardt, Boris, Bhatnagar, Shivani, Blümcke, Ingmar, Blumenfeld, Hal, Buchanan, Gordon F, Burdette, David E, Burneo, Jorge G, Busch, Robyn M, Chauvel, Patrick, Chin, Jeannie, Clifford, Lisa, Conner, Kelly R, Cook, Mark J, Conway, Jeannine, Diaz-Arastia, Ramon, Drees, Cornelia, French, Jacqueline A, Ganguly, Taneeta Mindy, Gelfand, Michael A, Glauser, Tracy A, Gleichgerrcht, Ezequiel, Goldman, Alica M, Gonzalez-Martinez, Jorge, Gotman, Jean, Grinspan, Zachary, Guilfoyle, Shanna, Gupta, Gita, Hammer, Michael, Hartman, Adam L, Hentges, Katie, Hogan, R Edward, Huh, Linda, Hyslop, Ann, Jobst, Barbara, Josephson, Colin B, Kelley, Sarah A, Knupp, Kelly, Koepp, Matthias, Kothare, Sanjeev V, Krook-Magnuson, Esther, Kwasa, Jasmine, La Vega-Talbott, Maite, Lam, Alice D, Lee, Jong Woo, Lowenstein, Daniel H, Maturu, Sarita, Mayor, Luis Carlos, McDonald, Carrie, McKee, Heather R, McKhann, Guy M, Meador, Kimford J, Mefford, Heather C, Michael, Elizabeth H, Mikati, Mohamad A, Millichap, John J, Mitchell, James W, Myers, Leah S, Naritoku, Dean, Neville, Kerri L, Noebels, Jeffrey, O’Brien, Terence J, Oluigbo, Chima O, Patel, Anup D, Pavlova, Milena K, T. Paz, Jeanne, Pennell, Page B, Perry, M Scott, Perucca, Piero, Pitkänen, Asla, Plueger, Madona, Pugh, Mary Jo, Quigg, Mark, Reddy, Shilpa B, Ryan, Christopher, Reynolds, Tamara S, Sajatovic, Martha, Santana-Gomez, Cesar, Schommer, Linsday, Schuele, Stephan, Shellhaas, Renée A, Shrey, Daniel W, Singh, Rani K, Sperling, Michael R, Suleman, Saher, Templer, Jessica W, Thom, Maria, and Trinka, Eugen
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Biomedical and Clinical Sciences ,Neurosciences ,Epilepsy ,Neurodegenerative ,Brain Disorders ,Neurological ,Good Health and Well Being ,epilepsy ,annual meeting ,American Epilepsy Society ,Biological psychology - Abstract
With more than 6000 attendees between in-person and virtual offerings, the American Epilepsy Society Meeting 2022 in Nashville, felt as busy as in prepandemic times. An ever-growing number of physicians, scientists, and allied health professionals gathered to learn a variety of topics about epilepsy. The program was carefully tailored to meet the needs of professionals with different interests and career stages. This article summarizes the different symposia presented at the meeting. Basic science lectures addressed the primary elements of seizure generation and pathophysiology of epilepsy in different disease states. Scientists congregated to learn about anti-seizure medications, mechanisms of action, and new tools to treat epilepsy including surgery and neurostimulation. Some symposia were also dedicated to discuss epilepsy comorbidities and practical issues regarding epilepsy care. An increasing number of patient advocates discussing their stories were intertwined within scientific activities. Many smaller group sessions targeted more specific topics to encourage member participation, including Special Interest Groups, Investigator, and Skills Workshops. Special lectures included the renown Hoyer and Lombroso, an ILAE/IBE joint session, a spotlight on the impact of Dobbs v. Jackson on reproductive health in epilepsy, and a joint session with the NAEC on coding and reimbursement policies. The hot topics symposium was focused on traumatic brain injury and post-traumatic epilepsy. A balanced collaboration with the industry allowed presentations of the latest pharmaceutical and engineering advances in satellite symposia.
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- 2023
7. Enhancing Ventilation of Enclosed Spaces Using CFD: Part 1: Lead Article
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Yadav, Mani S., Kothare, Nipun, Tamboli, Nikhil K., Murallidharan, Janani S., Kumaraswamy, Guruswamy, Singh, Abhimanyu, and Sinha, Krishnendu
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- 2024
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8. Deep Learning for Bias Detection: From Inception to Deployment
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Bashar, Md Abul, Nayak, Richi, Kothare, Anjor, Sharma, Vishal, and Kandadai, Kesavan
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Computer Science - Computation and Language ,Computer Science - Artificial Intelligence ,Computer Science - Machine Learning ,Computer Science - Neural and Evolutionary Computing ,Computer Science - Social and Information Networks - Abstract
To create a more inclusive workplace, enterprises are actively investing in identifying and eliminating unconscious bias (e.g., gender, race, age, disability, elitism and religion) across their various functions. We propose a deep learning model with a transfer learning based language model to learn from manually tagged documents for automatically identifying bias in enterprise content. We first pretrain a deep learning-based language-model using Wikipedia, then fine tune the model with a large unlabelled data set related with various types of enterprise content. Finally, a linear layer followed by softmax layer is added at the end of the language model and the model is trained on a labelled bias dataset consisting of enterprise content. The trained model is thoroughly evaluated on independent datasets to ensure a general application. We present the proposed method and its deployment detail in a real-world application.
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- 2021
9. Temporal specificity of abnormal neural oscillations during phonatory events in laryngeal dystonia
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Kothare, Hardik, Schneider, Sarah, Mizuiri, Danielle, Hinkley, Leighton, Bhutada, Abhishek, Ranasinghe, Kamalini, Honma, Susanne, Garrett, Coleman, Klein, David, Naunheim, Molly, Yung, Katherine, Cheung, Steven, Rosen, Clark, Courey, Mark, Nagarajan, Srikantan, and Houde, John
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Biological Psychology ,Biomedical and Clinical Sciences ,Psychology ,Biomedical Imaging ,Neurodegenerative ,Rare Diseases ,Clinical Research ,Dystonia ,Rehabilitation ,Neurosciences ,2.1 Biological and endogenous factors ,1.1 Normal biological development and functioning ,Neurological ,laryngeal dystonia ,spasmodic dysphonia ,magnetoencephalography ,vocal motor control ,voice disorders ,Clinical sciences ,Biological psychology - Abstract
Laryngeal dystonia is a debilitating disorder of voicing in which the laryngeal muscles are intermittently in spasm resulting in involuntary interruptions during speech. The central pathophysiology of laryngeal dystonia, underlying computational impairments in vocal motor control, remains poorly understood. Although prior imaging studies have found aberrant activity in the CNS during phonation in patients with laryngeal dystonia, it is not known at what timepoints during phonation these abnormalities emerge and what function may be impaired. To investigate this question, we recruited 22 adductor laryngeal dystonia patients (15 female, age range = 28.83-72.46 years) and 18 controls (eight female, age range = 27.40-71.34 years). We leveraged the fine temporal resolution of magnetoencephalography to monitor neural activity around glottal movement onset, subsequent voice onset and after the onset of pitch feedback perturbations. We examined event-related beta-band (12-30 Hz) and high-gamma-band (65-150 Hz) neural oscillations. Prior to glottal movement onset, we observed abnormal frontoparietal motor preparatory activity. After glottal movement onset, we observed abnormal activity in the somatosensory cortex persisting through voice onset. Prior to voice onset and continuing after, we also observed abnormal activity in the auditory cortex and the cerebellum. After pitch feedback perturbation onset, we observed no differences between controls and patients in their behavioural responses to the perturbation. But in patients, we did find abnormal activity in brain regions thought to be involved in the auditory feedback control of vocal pitch (premotor, motor, somatosensory and auditory cortices). Our study results confirm the abnormal processing of somatosensory feedback that has been seen in other studies. However, there were several remarkable findings in our study. First, patients have impaired vocal motor activity even before glottal movement onset, suggesting abnormal movement preparation. These results are significant because (i) they occur before movement onset, abnormalities in patients cannot be ascribed to deficits in vocal performance and (ii) they show that neural abnormalities in laryngeal dystonia are more than just abnormal responses to sensory feedback during phonation as has been hypothesized in some previous studies. Second, abnormal auditory cortical activity in patients begins even before voice onset, suggesting abnormalities in setting up auditory predictions before the arrival of auditory feedback at voice onset. Generally, activation abnormalities identified in key brain regions within the speech motor network around various phonation events not only provide temporal specificity to neuroimaging phenotypes in laryngeal dystonia but also may serve as potential therapeutic targets for neuromodulation.
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- 2022
10. Investigating the Utility of Multimodal Conversational Technology and Audiovisual Analytic Measures for the Assessment and Monitoring of Amyotrophic Lateral Sclerosis at Scale
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Neumann, Michael, Roesler, Oliver, Liscombe, Jackson, Kothare, Hardik, Suendermann-Oeft, David, Pautler, David, Navar, Indu, Anvar, Aria, Kumm, Jochen, Norel, Raquel, Fraenkel, Ernest, Sherman, Alexander V., Berry, James D., Pattee, Gary L., Wang, Jun, Green, Jordan R., and Ramanarayanan, Vikram
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Electrical Engineering and Systems Science - Audio and Speech Processing ,Computer Science - Sound - Abstract
We propose a cloud-based multimodal dialog platform for the remote assessment and monitoring of Amyotrophic Lateral Sclerosis (ALS) at scale. This paper presents our vision, technology setup, and an initial investigation of the efficacy of the various acoustic and visual speech metrics automatically extracted by the platform. 82 healthy controls and 54 people with ALS (pALS) were instructed to interact with the platform and completed a battery of speaking tasks designed to probe the acoustic, articulatory, phonatory, and respiratory aspects of their speech. We find that multiple acoustic (rate, duration, voicing) and visual (higher order statistics of the jaw and lip) speech metrics show statistically significant differences between controls, bulbar symptomatic and bulbar pre-symptomatic patients. We report on the sensitivity and specificity of these metrics using five-fold cross-validation. We further conducted a LASSO-LARS regression analysis to uncover the relative contributions of various acoustic and visual features in predicting the severity of patients' ALS (as measured by their self-reported ALSFRS-R scores). Our results provide encouraging evidence of the utility of automatically extracted audiovisual analytics for scalable remote patient assessment and monitoring in ALS.
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- 2021
11. Evaluating Sleep Disturbances in Children With Rare Genetic Neurodevelopmental Syndromes
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Veatch, Olivia J, Malow, Beth A, Lee, Hye-Seung, Knight, Aryn, Barrish, Judy O, Neul, Jeffrey L, Lane, Jane B, Skinner, Steven A, Kaufmann, Walter E, Miller, Jennifer L, Driscoll, Daniel J, Bird, Lynne M, Butler, Merlin G, Dykens, Elisabeth M, Gold, June-Anne, Kimonis, Virginia, Bacino, Carlos A, Tan, Wen-Hann, Kothare, Sanjeev V, Peters, Sarika U, Percy, Alan K, and Glaze, Daniel G
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Biomedical and Clinical Sciences ,Cardiovascular Medicine and Haematology ,Neurosciences ,Lung ,Pediatric ,Rare Diseases ,Behavioral and Social Science ,Intellectual and Developmental Disabilities (IDD) ,Genetics ,Mental Health ,Clinical Research ,Sleep Research ,Neurodegenerative ,Brain Disorders ,Adolescent ,Angelman Syndrome ,Child ,Child ,Preschool ,Humans ,Neurodevelopmental Disorders ,Prader-Willi Syndrome ,Rett Syndrome ,Sleep Wake Disorders ,Pediatric sleep ,Rare disease ,Genetic syndromes ,Neurodevelopment ,Paediatrics and Reproductive Medicine ,Neurology & Neurosurgery ,Paediatrics - Abstract
BackgroundAdequate sleep is important for proper neurodevelopment and positive health outcomes. Sleep disturbances are more prevalent in children with genetically determined neurodevelopmental syndromes compared with typically developing counterparts. We characterize sleep behavior in Rett (RTT), Angelman (AS), and Prader-Willi (PWS) syndromes to identify effective approaches for treating sleep problems in these populations. We compared sleep-related symptoms across individuals with these different syndromes with each other, and with typically developing controls.MethodsChildren were recruited from the Rare Diseases Clinical Research Network consortium registries; unaffected siblings were enrolled as related controls. For each participant, a parent completed multiple sleep questionnaires including Pediatric Sleep Questionnaire (Sleep-Disordered Breathing), Children's Sleep Habits Questionnaire (CSHQ), and Pediatric Daytime Sleepiness Scale.ResultsSleep data were analyzed from 714 participants, aged two to 18 years. Young children with AS had more reported sleep problems than children with RTT or PWS. Older children with RTT had more reported daytime sleepiness than those with AS or PWS. Finally, all individuals with RTT had more evidence of sleep-disordered breathing when compared with individuals with PWS. Notably, typically developing siblings were also reported to have sleep problems, except for sleep-related breathing disturbances, which were associated with each of the genetic syndromes.ConclusionsIndividuals with RTT, AS, and PWS frequently experience sleep problems, including sleep-disordered breathing. Screening for sleep problems in individuals with these and other neurogenetic disorders should be included in clinical assessment and managements. These data may also be useful in developing treatment strategies and in clinical trials.
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- 2021
12. Speech compensation responses and sensorimotor adaptation to formant feedback perturbations.
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Raharjo, Inez, Kothare, Hardik, Nagarajan, Srikantan S, and Houde, John F
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Acoustics - Abstract
Control of speech formants is important for the production of distinguishable speech sounds and is achieved with both feedback and learned feedforward control. However, it is unclear whether the learning of feedforward control involves the mechanisms of feedback control. Speakers have been shown to compensate for unpredictable transient mid-utterance perturbations of pitch and loudness feedback, demonstrating online feedback control of these speech features. To determine whether similar feedback control mechanisms exist in the production of formants, responses to unpredictable vowel formant feedback perturbations were examined. Results showed similar within-trial compensatory responses to formant perturbations that were presented at utterance onset and mid-utterance. The relationship between online feedback compensation to unpredictable formant perturbations and sensorimotor adaptation to consistent formant perturbations was further examined. Within-trial online compensation responses were not correlated with across-trial sensorimotor adaptation. A detailed analysis of within-trial time course dynamics across trials during sensorimotor adaptation revealed that across-trial sensorimotor adaptation responses did not result from an incorporation of within-trial compensation response. These findings suggest that online feedback compensation and sensorimotor adaptation are governed by distinct neural mechanisms. These findings have important implications for models of speech motor control in terms of how feedback and feedforward control mechanisms are implemented.
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- 2021
13. Sensorimotor adaptation of speech depends on the direction of auditory feedback alteration
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Kothare, Hardik, Raharjo, Inez, Ramanarayanan, Vikram, Ranasinghe, Kamalini, Parrell, Benjamin, Johnson, Keith, Houde, John F, and Nagarajan, Srikantan S
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Allied Health and Rehabilitation Science ,Health Sciences ,Clinical Research ,Rehabilitation ,Feedback ,Feedback ,Sensory ,Humans ,Speech ,Speech Acoustics ,Speech Perception ,Acoustics - Abstract
A hallmark feature of speech motor control is its ability to learn to anticipate and compensate for persistent feedback alterations, a process referred to as sensorimotor adaptation. Because this process involves adjusting articulation to counter the perceived effects of altering acoustic feedback, there are a number of factors that affect it, including the complex relationship between acoustics and articulation and non-uniformities of speech perception. As a consequence, sensorimotor adaptation is hypothesised to vary as a function of the direction of the applied auditory feedback alteration in vowel formant space. This hypothesis was tested in two experiments where auditory feedback was altered in real time, shifting the frequency values of the first and second formants (F1 and F2) of participants' speech. Shifts were designed on a subject-by-subject basis and sensorimotor adaptation was quantified with respect to the direction of applied shift, normalised for individual speakers. Adaptation was indeed found to depend on the direction of the applied shift in vowel formant space, independent of shift magnitude. These findings have implications for models of sensorimotor adaptation of speech.
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- 2020
14. Establishing a Causal Role for Medial Prefrontal Cortex in Reality Monitoring
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Subramaniam, Karuna, Kothare, Hardik, Hinkley, Leighton B, Tarapore, Phiroz, and Nagarajan, Srikantan S
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- 2020
15. Time-Dependent Transformations of Memory Representations Differ along the Long Axis of the Hippocampus
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Cowan, Emily T., Liu, Anli A., Henin, Simon, Kothare, Sanjeev, Devinsky, Orrin, and Davachi, Lila
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Research has shown that sleep is beneficial for the long-term retention of memories. According to theories of memory consolidation, memories are gradually reorganized, becoming supported by widespread, distributed cortical networks, particularly during postencoding periods of sleep. However, the effects of sleep on the organization of memories in the hippocampus itself remains less clear. In a 3-d study, participants encoded separate lists of word-image pairs differing in their opportunity for sleep-dependent consolidation. Pairs were initially studied either before or after an overnight sleep period, and were then restudied in a functional magnetic resonance imaging (fMRI) scan session. We used multivariate pattern similarity analyses to examine fine-grained effects of consolidation on memory representations in the hippocampus. We provide evidence for a dissociation along the long axis of the hippocampus that emerges with consolidation, such that representational patterns for object-word memories initially formed prior to sleep become differentiated in anterior hippocampus and more similar, or overlapping, in posterior hippocampus. Differentiation in anterior hippocampal representations correlated with subsequent behavioral performance. Furthermore, representational overlap in posterior hippocampus correlated with the duration of intervening slow wave sleep. Together, these results demonstrate that sleep-dependent consolidation promotes the reorganization of memory traces along the long axis of the hippocampus.
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- 2021
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16. Beta-band activity in medial prefrontal cortex predicts source memory encoding and retrieval accuracy.
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Subramaniam, Karuna, Hinkley, Leighton BN, Mizuiri, Danielle, Kothare, Hardik, Cai, Chang, Garrett, Coleman, Findlay, Anne, Houde, John F, and Nagarajan, Srikantan S
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Prefrontal Cortex ,Humans ,Magnetic Resonance Imaging ,Beta Rhythm ,Brain Mapping ,Cognition ,Memory ,Mental Recall ,Decision Making ,Reaction Time ,Adult ,Middle Aged ,Female ,Male ,Young Adult - Abstract
Reality monitoring is defined as the ability to distinguish internally self-generated information from externally-derived information. The medial prefrontal cortex (mPFC) is a key brain region subserving reality monitoring and has been shown to be activated specifically during the retrieval of self-generated information. However, it is unclear if mPFC is activated during the encoding of self-generated information into memory. If so, it is important to understand whether successful retrieval of self-generated information critically depends on enhanced neural activity within mPFC during initial encoding of this self-generated information. We used magnetoencephalographic imaging (MEGI) to determine the timing and location of cortical activity during a reality-monitoring task involving self generated contextual source memory encoding and retrieval. We found both during encoding and retrieval of self-generated information, when compared to externally-derived information, mPFC showed significant task induced oscillatory power modulation in the beta-band. During initial encoding of self-generated information, greater mPFC beta-band power reductions occurred within a time window of -700 ms to -500 ms prior to vocalization. This increased activity in mPFC was not observed during encoding of externally-derived information. Additionally, increased mPFC activity during encoding of self-generated information predicted subsequent retrieval accuracy of this self-generated information. Beta-band activity in mPFC was also observed during the initial retrieval of self-generated information within a time window of 300 to 500 ms following stimulus onset and correlated with accurate retrieval performance of self-generated information. Together, these results further highlight the importance of mPFC in mediating the initial generation and awareness of participants' internal thoughts.
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- 2019
17. Abnormally increased vocal responses to pitch feedback perturbations in patients with cerebellar degeneration
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Houde, John F, Gill, Jeevit S, Agnew, Zarinah, Kothare, Hardik, Hickok, Gregory, Parrell, Benjamin, Ivry, Richard B, and Nagarajan, Srikantan S
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Biological Psychology ,Biomedical and Clinical Sciences ,Psychology ,Clinical Trials and Supportive Activities ,Clinical Research ,Acoustic Stimulation ,Adult ,Feedback ,Feedback ,Sensory ,Female ,Humans ,Male ,Middle Aged ,Pitch Perception ,Speech ,Speech Perception ,Voice ,Acoustics - Abstract
Cerebellar degeneration (CD) has deleterious effects on speech motor behavior. Recently, a dissociation between feedback and feedforward control of speaking was observed in CD: Whereas CD patients exhibited reduced adaptation across trials to consistent formant feedback alterations, they showed enhanced within-trial compensation for unpredictable formant feedback perturbations. In this study, it was found that CD patients exhibit abnormally increased within-trial vocal compensation responses to unpredictable pitch feedback perturbations. Taken together with recent findings, the results indicate that CD is associated with a general hypersensitivity to auditory feedback during speaking.
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- 2019
18. Neural correlates of abnormal auditory feedback processing during speech production in Alzheimer's disease.
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Ranasinghe, Kamalini G, Kothare, Hardik, Kort, Naomi, Hinkley, Leighton B, Beagle, Alexander J, Mizuiri, Danielle, Honma, Susanne M, Lee, Richard, Miller, Bruce L, Gorno-Tempini, Maria Luisa, Vossel, Keith A, Houde, John F, and Nagarajan, Srikantan S
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Brain ,Humans ,Alzheimer Disease ,Acoustic Stimulation ,Speech ,Pitch Perception ,Phonation ,Middle Aged ,Female ,Male ,Feedback ,Sensory ,Feedback ,Sensory ,Basic Behavioral and Social Science ,Clinical Research ,Aging ,Acquired Cognitive Impairment ,Brain Disorders ,Alzheimer's Disease ,Alzheimer's Disease including Alzheimer's Disease Related Dementias ,Neurodegenerative ,Dementia ,Behavioral and Social Science ,Rehabilitation ,Neurosciences ,2.1 Biological and endogenous factors ,Neurological ,Biochemistry and Cell Biology ,Other Physical Sciences - Abstract
Accurate integration of sensory inputs and motor commands is essential to achieve successful behavioral goals. A robust model of sensorimotor integration is the pitch perturbation response, in which speakers respond rapidly to shifts of the pitch in their auditory feedback. In a previous study, we demonstrated abnormal sensorimotor integration in patients with Alzheimer's disease (AD) with an abnormally enhanced behavioral response to pitch perturbation. Here we examine the neural correlates of the abnormal pitch perturbation response in AD patients, using magnetoencephalographic imaging. The participants phonated the vowel /α/ while a real-time signal processor briefly perturbed the pitch (100 cents, 400 ms) of their auditory feedback. We examined the high-gamma band (65-150 Hz) responses during this task. AD patients showed significantly reduced left prefrontal activity during the early phase of perturbation and increased right middle temporal activity during the later phase of perturbation, compared to controls. Activity in these brain regions significantly correlated with the behavioral response. These results demonstrate that impaired prefrontal modulation of speech-motor-control network and additional recruitment of right temporal regions are significant mediators of aberrant sensorimotor integration in patients with AD. The abnormal neural integration mechanisms signify the contribution of cortical network dysfunction to cognitive and behavioral deficits in AD.
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- 2019
19. A randomized controlled trial of levodopa in patients with Angelman syndrome
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Tan, Wen‐Hann, Bird, Lynne M, Sadhwani, Anjali, Barbieri‐Welge, Rene L, Skinner, Steven A, Horowitz, Lucia T, Bacino, Carlos A, Noll, Lisa M, Fu, Cary, Hundley, Rachel J, Wink, Logan K, Erickson, Craig A, Barnes, Gregory N, Slavotinek, Anne, Jeremy, Rita, Rotenberg, Alexander, Kothare, Sanjeev V, Olson, Heather E, Poduri, Annapurna, Nespeca, Mark P, Chu, Hillary C, Willen, Jennifer M, Haas, Kevin F, Weeber, Edwin J, and Rufo, Paul A
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Biomedical and Clinical Sciences ,Clinical Sciences ,Neurosciences ,Clinical Research ,Brain Disorders ,Prevention ,Pediatric ,Clinical Trials and Supportive Activities ,Evaluation of treatments and therapeutic interventions ,6.1 Pharmaceuticals ,Angelman Syndrome ,Animals ,Biomarkers ,Calcium ,Calcium-Calmodulin-Dependent Protein Kinase Type 2 ,Disease Models ,Animal ,Humans ,Levodopa ,Long-Term Potentiation ,Mice ,Neuropsychological Tests ,Treatment Outcome ,calcium-calmodulin-dependent protein kinase type 2 ,clinical trial ,developmental disabilities ,inborn genetic diseases ,rare disease ,UBE3A ,Genetics ,Clinical sciences - Abstract
Treatment for Angelman syndrome (AS) is currently limited to symptomatic interventions. A mouse model of AS has reduced calcium/calmodulin-dependent kinase II activity due to excessive phosphorylation of specific threonine residues, leading to diminished long-term potentiation. In a rat model of Parkinson disease, levodopa reduced phosphorylation of various proteins, including calcium/calmodulin-dependent kinase II. Further studies demonstrated that AS mice treated with levodopa performed better on rotarod testing than untreated AS mice. We conducted a multi-center double-blind randomized placebo-controlled 1-year trial of levodopa / carbidopa with either 10 or 15 mg/kg/day of levodopa in children with AS. The outcome of this intervention was assessed using either the Bayley Scales of Infant Development or the Mullen Scales of Early Learning, as well as the Vineland Adaptive Behavior Scales, and the Aberrant Behavior Checklist. Of the 78 participants enrolled, 67 participants received study medication (33 on levodopa, 34 on placebo), and 55 participants (29 on levodopa, 26 on placebo) completed the 1-year study. There were no clinically or statistically significant changes in any of the outcome measures over a 1-year period comparing the levodopa and placebo groups. The number of adverse events reported, including the more serious adverse events, was similar in both groups, but none were related to treatment with levodopa. Our data demonstrate that levodopa is well-tolerated by children with AS. However, in the doses used in this study, it failed to improve their neurodevelopment or behavioral outcome.
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- 2018
20. Abnormal Speech Motor Control in Individuals with 16p11.2 Deletions.
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Demopoulos, Carly, Kothare, Hardik, Mizuiri, Danielle, Henderson-Sabes, Jennifer, Fregeau, Brieana, Tjernagel, Jennifer, Houde, John F, Sherr, Elliott H, and Nagarajan, Srikantan S
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Chromosomes ,Human ,Pair 16 ,Humans ,Chromosome Disorders ,Chromosome Deletion ,Speech ,Autistic Disorder ,Adaptation ,Physiological ,Voice ,Adolescent ,Child ,Female ,Male ,Intellectual Disability ,Chromosomes ,Human ,Pair 16 ,Adaptation ,Physiological - Abstract
Speech and motor deficits are highly prevalent (>70%) in individuals with the 600 kb BP4-BP5 16p11.2 deletion; however, the mechanisms that drive these deficits are unclear, limiting our ability to target interventions and advance treatment. This study examined fundamental aspects of speech motor control in participants with the 16p11.2 deletion. To assess capacity for control of voice, we examined how accurately and quickly subjects changed the pitch of their voice within a trial to correct for a transient perturbation of the pitch of their auditory feedback. When compared to controls, 16p11.2 deletion carriers show an over-exaggerated pitch compensation response to unpredictable mid-vocalization pitch perturbations. We also examined sensorimotor adaptation of speech by assessing how subjects learned to adapt their sustained productions of formants (speech spectral peak frequencies important for vowel identity), in response to consistent changes in their auditory feedback during vowel production. Deletion carriers show reduced sensorimotor adaptation to sustained vowel identity changes in auditory feedback. These results together suggest that 16p11.2 deletion carriers have fundamental impairments in the basic mechanisms of speech motor control and these impairments may partially explain the deficits in speech and language in these individuals.
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- 2018
21. Reality Monitoring and Feedback Control of Speech Production Are Related Through Self-Agency
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Subramaniam, Karuna, Kothare, Hardik, Mizuiri, Danielle, Nagarajan, Srikantan S, and Houde, John F
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Cognitive and Computational Psychology ,Psychology ,Clinical Research ,Behavioral and Social Science ,self-agency ,reality monitoring ,speech feedback monitoring ,pitch perturbation ,predicting self-generated action outcomes ,Neurosciences ,Cognitive Sciences ,Experimental Psychology ,Biological psychology ,Cognitive and computational psychology - Abstract
Self-agency is the experience of being the agent of one's own thoughts and motor actions. The intact experience of self-agency is necessary for successful interactions with the outside world (i.e., reality monitoring) and for responding to sensory feedback of our motor actions (e.g., speech feedback control). Reality monitoring is the ability to distinguish internally self-generated information from outside reality (externally-derived information). In the present study, we examined the relationship of self-agency between lower-level speech feedback monitoring (i.e., monitoring what we hear ourselves say) and a higher-level cognitive reality monitoring task. In particular, we examined whether speech feedback monitoring and reality monitoring were driven by the capacity to experience self-agency-the ability to make reliable predictions about the outcomes of self-generated actions. During the reality monitoring task, subjects made judgments as to whether information was previously self-generated (self-agency judgments) or externally derived (external-agency judgments). During speech feedback monitoring, we assessed self-agency by altering environmental auditory feedback so that subjects listened to a perturbed version of their own speech. When subjects heard minimal perturbations in their auditory feedback while speaking, they made corrective responses, indicating that they judged the perturbations as errors in their speech output. We found that self-agency judgments in the reality-monitoring task were higher in people who had smaller corrective responses (p = 0.05) and smaller inter-trial variability (p = 0.03) during minimal pitch perturbations of their auditory feedback. These results provide support for a unitary process for the experience of self-agency governing low-level speech control and higher level reality monitoring.
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- 2018
22. Abnormal vocal behavior predicts executive and memory deficits in Alzheimer's disease
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Ranasinghe, Kamalini G, Gill, Jeevit S, Kothare, Hardik, Beagle, Alexander J, Mizuiri, Danielle, Honma, Susanne M, Gorno-Tempini, Maria Luisa, Miller, Bruce L, Vossel, Keith A, Nagarajan, Srikantan S, and Houde, John F
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Biological Psychology ,Psychology ,Behavioral and Social Science ,Neurosciences ,Rehabilitation ,Basic Behavioral and Social Science ,Clinical Research ,Neurodegenerative ,Acquired Cognitive Impairment ,Alzheimer's Disease ,Dementia ,Aging ,Alzheimer's Disease including Alzheimer's Disease Related Dementias (AD/ADRD) ,Brain Disorders ,2.1 Biological and endogenous factors ,Neurological ,Aged ,Alzheimer Disease ,Executive Function ,Feedback ,Sensory ,Female ,Forecasting ,Humans ,Male ,Memory ,Memory Disorders ,Middle Aged ,Pitch Perception ,Prefrontal Cortex ,Reflex ,Speech ,Verbal Behavior ,Alzheimer's disease ,Pitch perturbation ,Network disruption ,Executive dysfunction ,Prefrontal modulation ,Sensorimotor integration ,Clinical Sciences ,Neurology & Neurosurgery ,Biological psychology - Abstract
Speakers respond automatically and rapidly to compensate for brief perturbations of pitch in their auditory feedback. The specific adjustments in vocal output require integration of brain regions involved in speech-motor-control in order to detect the sensory-feedback error and implement the motor correction. Cortical regions involved in the pitch reflex phenomenon are highly vulnerable targets of network disruption in Alzheimer's disease (AD). We examined the pitch reflex in AD patients (n = 19) compared to an age-matched control group (n = 16). We measured the degree of behavioral compensation (peak compensation) and the extent of the adaptive response (pitch-response persistence). Healthy-controls reached a peak compensation of 18.7 ± 0.8 cents, and demonstrated a sustained compensation at 8.9 ± 0.69 cents. AD patients, in contrast, demonstrated a significantly elevated peak compensation (22.4 ± 1.2 cents, p < 0.05), and a reduced sustained response (pitch-response persistence, 4.5 ± 0.88 cents, p < 0.001). The degree of increased peak compensation predicted executive dysfunction, while the degree of impaired pitch-response persistence predicted memory dysfunction, in AD patients. The current study demonstrates pitch reflex as a sensitive behavioral index of impaired prefrontal modulation of sensorimotor integration, and compromised plasticity mechanisms of memory, in AD.
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- 2017
23. Experimental design of a “Snap-on” and standalone single-bed oxygen concentrator for medical applications
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Vemula, Rama Rao, Urich, Matthew D., and Kothare, Mayuresh V.
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- 2021
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24. Optimal Sparse Output Feedback Control Design: a Rank Constrained Optimization Approach
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Arastoo, Reza, Motee, Nader, and Kothare, Mayuresh V.
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Mathematics - Optimization and Control - Abstract
We consider the problem of optimal sparse output feedback controller synthesis for continuous linear time invariant systems when the feedback gain is static and subject to specified structural constraints. Introducing an additional term penalizing the number of non-zero entries of the feedback gain into the optimization cost function, we show that this inherently non-convex problem can be equivalently cast as a rank constrained optimization, hence, it is an NP-hard problem. We further exploit our rank constrained approach to define a structured output feedback control feasibility test with global convergence property, then, obtain upper/lower bounds for the optimal cost of the sparse output feedback control problem. Moreover, we show that our problem reformulation allows us to incorporate additional implementation constraints, such as norm bounds on the control inputs or system output, by assimilating them into the rank constraint. We propose to utilize a version of the Alternating Direction Method of Multipliers (ADMM) as an efficient method to sub-optimally solve the equivalent rank constrained problem. As a special case, we study the problem of designing the sparsest stabilizing output feedback controller, and show that it is, in fact, a structured matrix recovery problem where the matrix of interest is simultaneously sparse and low rank. Furthermore, we show that this matrix recovery problem can be equivalently cast in the form of a canonical and well-studied rank minimization problem. We finally illustrate performance of our proposed methodology using numerical examples.
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- 2014
25. SLC25A22 is a novel gene for migrating partial seizures in infancy
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Poduri, Annapurna, Heinzen, Erin L, Chitsazzadeh, Vida, Lasorsa, Francesco Massimo, Elhosary, P Christina, LaCoursiere, Christopher M, Martin, Emilie, Yuskaitis, Christopher J, Hill, Robert Sean, Atabay, Kutay Deniz, Barry, Brenda, Partlow, Jennifer N, Bashiri, Fahad A, Zeidan, Radwan M, Elmalik, Salah A, Kabiraj, Mohammad MU, Kothare, Sanjeev, Stödberg, Tommy, McTague, Amy, Kurian, Manju A, Scheffer, Ingrid E, Barkovich, A James, Palmieri, Ferdinando, Salih, Mustafa A, and Walsh, Christopher A
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Biomedical and Clinical Sciences ,Neurosciences ,Clinical Sciences ,Genetics ,Neurodegenerative ,Human Genome ,Biotechnology ,Brain Disorders ,Epilepsy ,Clinical Research ,Pediatric ,2.1 Biological and endogenous factors ,Aetiology ,Neurological ,Adult ,Consanguinity ,Epilepsy ,Benign Neonatal ,Exome ,Female ,Genetic Linkage ,Humans ,Infant ,Newborn ,Male ,Mitochondrial Membrane Transport Proteins ,Pedigree ,Neurology & Neurosurgery ,Clinical sciences - Abstract
ObjectiveTo identify a genetic cause for migrating partial seizures in infancy (MPSI).MethodsWe characterized a consanguineous pedigree with MPSI and obtained DNA from affected and unaffected family members. We analyzed single nucleotide polymorphism 500K data to identify regions with evidence of linkage. We performed whole exome sequencing and analyzed homozygous variants in regions of linkage to identify a candidate gene and performed functional studies of the candidate gene SLC25A22.ResultsIn a consanguineous pedigree with 2 individuals with MPSI, we identified 2 regions of linkage, chromosome 4p16.1-p16.3 and chromosome 11p15.4-pter. Using whole exome sequencing, we identified 8 novel homozygous variants in genes in these regions. Only 1 variant, SLC25A22 c.G328C, results in a change of a highly conserved amino acid (p.G110R) and was not present in control samples. SLC25A22 encodes a glutamate transporter with strong expression in the developing brain. We show that the specific G110R mutation, located in a transmembrane domain of the protein, disrupts mitochondrial glutamate transport.InterpretationWe have shown that MPSI can be inherited and have identified a novel homozygous mutation in SLC25A22 in the affected individuals. Our data strongly suggest that SLC25A22 is responsible for MPSI, a severe condition with few known etiologies. We have demonstrated that a combination of linkage analysis and whole exome sequencing can be used for disease gene discovery. Finally, as SLC25A22 had been implicated in the distinct syndrome of neonatal epilepsy with suppression bursts on electroencephalogram, we have expanded the phenotypic spectrum associated with SLC25A22.
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- 2013
26. Sensorimotor Integration in Speech Production
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Kothare, Hardik
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Bioengineering ,Neurosciences ,Formant Adaptation ,Laryngeal Dystonia ,Primary Progressive Aphasia ,Sensorimotor Integration ,Spasmodic Dysphonia ,Speech Neuroscience - Abstract
When we speak, there’s a complex sequence of events occurring within us. A symphony, if you will, with the brain as the conductor; the respiratory muscles pushing air out of our bellow-like lungs; this exhaled air setting the vocal cords into vibration like the strings of a musical instrument; the tongue, lips, nose, teeth and jaw acting as an ensemble and obstructing this air flow to produce speech sounds. The smooth execution of this sequence of events requires the human brain to monitor sensory feedback during speech, correct for any errors and learn from any past errors. This phenomenon is called sensorimotor integration and is essential for efficient speech motor control. Various theoretical and computational models of speech production explain how sensorimotor integration occurs but many aspects of this process still remain underexplored. This dissertation starts by investigating how sensorimotor learning of vowels depends on the complex relationship between articulatory dimensions and acoustic space. Specifically, formant adaptation or response to altered formant frequency feedback depends on the direction of the shift in two-dimensional F1-F2 vowel space. Using magnetoencephalographic imaging, I then investigate how sensorimotor integration is affected during speaking in a voice disorder called Laryngeal Dystonia (or Spasmodic Dysphonia). Significant differences in neural activity at various nodes of the speech motor control network were observed in patients with Laryngeal Dystonia at various time points around the act ofphonation. Lastly, the dissertation describes cortical dynamics of the speech motor control network in a neurodegenerative disorder affecting speech and language called the non-fluent variant of Primary Progressive Aphasia (nfvPPA). These patients have significant motor speech impairments which were investigated using a pitch perturbation experimental paradigm. Neural and behavioural results showed that sensorimotor integration is severely impacted in patients with nfvPPA. Taken together, the work in this dissertation aims to help inform current computational models of speech production and underlines the important role of sensorimotor integration in human speech.
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- 2020
27. Safety & feasibility of responsive neurostimulation in children with refractory epilepsy: A single-center experience.
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Enner, Stephanie, El-Hallal, Maria, Hogan, Katherine, Rodgers, Shaun, Karkare, Shefali, and Kothare, Sanjeev
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• RNS is a feasible and safe option for children as young as six years with refractory epilepsy. • RNS can be an effective treatment option for seizure control in refractory pediatric epilepsy. • RNS can be used in conjunction with other epilepsy surgery modalities. Responsive neurostimulation (RNS) is a relatively recent addition to the epilepsy surgery armory, gaining FDA approval in 2013 for use in adults with intractable focal epilepsy. Data for the use of RNS system in patients less than 18 years of age is limited. We aim to determine the safety and feasibility of RNS in children with refractory epilepsy. A retrospective chart review was conducted for all patients who underwent RNS implantation at an urban tertiary children's hospital. Demographics of the patients were obtained, including age at the time of implant, MRI findings, seizure onset zone identification, and RNS targets. Out of a fourteen patient cohort, one patient had a post-operative complication of infection at surgical site requiring explantation. Thirteen out of 14 patients had immediate post-operative head imaging that was negative for hemorrhage, infarction, or skull fracture; one patient did not undergo head imaging. No patients reported a worsening clinical seizure frequency at a 6-month follow up visit. In the subset of patients who were implanted with RNS and did not undergo concurrent resections, there was a statistically significant reduction in the average number of long episodes at the most recent visit when compared to the 1-month post-operative visit (p = 0.0268). RNS is a feasible and safe option for children as young as six years with refractory epilepsy when appropriate seizure focus identification has been performed with stereo CT and stereo EEG evaluations, and can be used in conjunction with other surgical epilepsy treatment modalities. Two canister RNS placement is achievable for patients with a broad epileptogenic network or multifocal seizure onset zones. [ABSTRACT FROM AUTHOR]
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- 2024
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28. Soft X-ray Focusing Telescope Aboard AstroSat: Design, Characteristics and Performance
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Singh, K. P., Stewart, G. C., Westergaard, N. J., Bhattacharayya, S., Chandra, S., Chitnis, V. R., Dewangan, G. C., Kothare, A. T., Mirza, I. M., Mukerjee, K., Navalkar, V., Shah, H., Abbey, A. F., Beardmore, A. P., Kotak, S., Kamble, N., Vishwakarama, S., Pathare, D. P., Risbud, V. M., Koyande, J. P., Stevenson, T., Bicknell, C., Crawford, T., Hansford, G., Peters, G., Sykes, J., Agarwal, P., Sebastian, M., Rajarajan, A., Nagesh, G., Narendra, S., Ramesh, M., Rai, R., Navalgund, K. H., Sarma, K. S., Pandiyan, R., Subbarao, K., Gupta, T., Thakkar, N., Singh, A. K., and Bajpai, A.
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- 2017
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29. An Integrated Strategy for Implementation of Dried Blood Spots in Clinical Development Programs
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Kothare, Prajakti A., Bateman, Kevin P., Dockendorf, Marissa, Stone, Julie, Xu, Yang, Woolf, Eric, and Shipley, Lisa A.
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- 2016
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30. Performance improvement and CO and HC emission reduction of variable compression ratio spark-ignition engine using n-pentanol as a fuel additive.
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Kothare, Chandrakant B., Kongre, Suhas, Malwe, Prateek, Sharma, Kamal, Qasem, Naef A.A., Ağbulut, Ümit, Eldin, Sayed M., and Panchal, Hitesh
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FUEL additives ,GREENHOUSE gas mitigation ,GASOLINE ,ENERGY consumption ,RUNNING speed ,FUEL tanks - Abstract
This study tests binary and ternary n-pentanol, ethanol, and petrol blends to increase spark-ignition (SI) engine performance and minimize CO and HC emissions. To improve brake thermal efficiency (BTE) and reduce emissions, adding ethanol into gasoline is one of the practices used in Automobiles. But the literature reported some performance limitations and problems with adding a high ethanol concentration to gasoline as phase separation problem occurs in fuel tank due to the hygroscopic nature of ethanol, a higher ethanol concentration may corrode some parts of the fuel supply system. Ethanol has a lower calorific value than gasoline, so a higher ethanol concentration in blends beyond a specific limit reduces BTE. N-pentanol as a fuel additive in gasoline can better solve these problems due to its high caloric value compared to ethanol. Also, when n-pentanol is mixed with gasoline and exposed to moisture, it does not separate in stages as in the ethanol case. Accordingly, this research aims to evaluate n-pentanol's viability as a fuel additive in petrol and ethanol-gasoline blends at different compression ratios. The experiments were carried out on a single-cylinder, four-stroke spark-ignition engine running at a constant speed. Different blends of n-pentanol with gasoline and ethanol were tested, and results were compared against gasoline and E10 (the optimal blend of ethanol-gasoline, 10/90 v/v %). Various parameters were examined, including BTE, brake-specific fuel consumption (BSFC), and different exhaust pollutants. The effects of compression ratio values on these parameters were also recorded. The 1.5 vol% pentanol with E10 (E10P1.5) mix has the best overall characteristics, including low BSFC, high BTE, and low CO and HC emissions compared to petrol and E10 fuels. E10P1.5 shows a maximum enhancement in BTE, low BSFC, CO reduction, and HC reduction by 23.79%, 19.80%, 37.79%, and 19.46%, respectively, over gasoline. Compared to E10, the improvement is 3.64% for BTE, 4.59% for BSFC, 8.88% for CO emission reduction, and 4.13% for HC emission reduction. [ABSTRACT FROM AUTHOR]
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- 2023
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31. Nonlinear Closed-Loop Predictive Control of Heart Rate and Blood Pressure Using Vagus Nerve Stimulation: An In Silico Study
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Yao, Yuyu and Kothare, Mayuresh V.
- Abstract
We propose a nonlinear model-based control technique for regulating the heart rate and blood pressure using vagus nerve neuromodulation. The closed-loop framework is based on an in silico model of the rat cardiovascular system for the simulation of the hemodynamic response to multi-location vagal nerve stimulation. The in silico model is derived by compartmentalizing the various physiological components involved in the closed-loop cardiovascular system with intrinsic baroreflex regulation to virtually generate nominal and hypertension-related heart dynamics of rats in rest and exercise states. The controller, using a reduced cycle-averaged model, monitors the outputs from the in silico model, estimates the current state of the reduced model, and computes the optimum stimulation locations and the corresponding parameters using a nonlinear model predictive control algorithm. The results demonstrate that the proposed control strategy is robust with respect to its ability to handle setpoint tracking and disturbance rejection in different simulation scenarios.
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- 2023
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32. Highlights of non-equilibrium, non-isobaric, non-isothermal desorption of nitrogen from a LiX zeolite column by rapid pressure reduction and rapid purge by oxygen
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Rama Rao, V., Chai, S. W., Kothare, M. V., and Sircar, S.
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- 2014
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33. Numerical simulation of rapid pressurization and depressurization of a zeolite column using nitrogen
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Rao, Vemula Rama, Kothare, Mayuresh V., and Sircar, Shivaji
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- 2014
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34. Gene regulatory network modeling using literature curated and high throughput data
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Kulkarni, Vishwesh V., Arastoo, Reza, Bhat, Anupama, Subramanian, Kalyansundaram, Kothare, Mayuresh V., and Riedel, Marc C.
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- 2012
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35. Numerical study of nitrogen desorption by rapid oxygen purge for a medical oxygen concentrator
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Chai, Siew Wah, Kothare, Mayuresh V., and Sircar, Shivaji
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- 2012
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36. Nonlinear Model Predictive Control of Vagal Nerve Stimulation to regulate hemodynamic variables
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Adeodu, Oluwasanmi, Gee, Michelle, Mahmoudi, Babak, Vadigepalli, Rajanikanth, and Kothare, Mayuresh
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Various pre-clinical investigations indicate that the electrical stimulation of the cervical branch of the vagus that innervates the heart has therapeutic value in the management of various cardiac diseases. In theory, the design of a closed-loop control mechanism that automatically adjusts vagal nerve stimulation (VNS) parameters based on real-time physiological feedback can eliminate intra-patient variability in VNS outcomes and therefore represents a major step towards patient-specific therapy. This study develops a nonlinear model predictive control (NMPC) approach for VNS of a pulsatile, human cardio-baroreflex system. The manipulated variables are the frequency and amplitude of a charge-balanced biphasic current. The effects of these variables on hemodynamic quantities such as heart rate, blood pressure, heart contractility e.t.c. are estimated under the assumption that the desired activation of efferent vagal nerve fibers within the vagosympathetic complex can not be realistically isolated from the off-target activation of afferent fibers. An approximate, cycle-averaged cardiovascular model is derived to eliminate pulsatility and is used for prediction in the controller. The feasibility of this NMPC scheme is explored with a set-point tracking example.
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- 2023
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37. Impact of fenfluramine on the expected SUDEP mortality rates in patients with Dravet syndrome.
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Cross, J. Helen, Galer, Bradley S., Gil-Nagel, Antonio, Devinsky, Orrin, Ceulemans, Berten, Lagae, Lieven, Schoonjans, An-Sofie, Donner, Elizabeth, Wirrell, Elaine, Kothare, Sanjeev, Agarwal, Anupam, Lock, Michael, and Gammaitoni, Arnold R.
- Abstract
Purpose: To assess the impact of fenfluramine (FFA) on the expected mortality incidence, including sudden unexpected death in epilepsy (SUDEP), in persons with Dravet syndrome (DS).Methods: In this pooled analysis, total time of exposure for persons with DS who were treated with FFA in phase 3 clinical trials, in United States and European Early Access Programs, and in two long-term open-label observational studies in Belgium was calculated. Literature was searched for reports of SUDEP mortality in DS, which were utilized as a comparison. Mortality rates were expressed per 1000 person-years.Results: A total of 732 persons with DS were treated with FFA, representing a total of 1185.3 person-years of exposure. Three deaths occurred, all in the phase 3 program: one during placebo treatment (probable SUDEP) and two during treatment with FFA (one probable SUDEP and one definite SUDEP). The all-cause and SUDEP mortality rates during treatment with FFA was 1.7 per 1000 person-years (95% CI, 0.4 to 6.7), a value lower than the all-cause estimate of 15.8 per 1000 person-years (95% CI, 9.9 to 25.4) and SUDEP estimate of 9.3 (95% CI, 5.0 to 17.3) reported by Cooper et al. (Epilepsy Res 2016;128:43-7) for persons with DS receiving standard-of-care.Conclusion: All-cause and SUDEP mortality rates in DS patients treated with FFA were substantially lower than in literature reports. Further studies are warranted to confirm that FFA reduces SUDEP risk in DS patients and to better understand the potential mechanism(s) by which FFA lowers SUDEP risk.Clinical Trial Registration: NCT02926898, NCT02682927, NCT02826863, NCT02823145, NCT03780127. [ABSTRACT FROM AUTHOR]- Published
- 2021
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38. Applications of bromelain from pineapple waste towards acne.
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Abbas, Sukaina, Shanbhag, Tejashree, and Kothare, Amruta
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Bromelain is a proteolytic mixture obtained from pineapple (Ananas comosus (L. Merr)). It has diversified clinical properties and is used in alleviation of cancer, inflammation and oxidative stress. The current study focuses on extraction of bromelain from different parts of pineapple such as core, crown, fruit, peel and stem. The extracted enzyme was precipitated using ammonium sulphate at 40% saturation followed by dialysis. The fold of purification obtained for peel, crown, core, fruit and stem were found to be 1.948, 1.536, 1,027, 1.989, and 1.232 respectively. Bromelain activity was estimated using Azocasein assay, the highest activity was seen in peel at 3.417 U/μg. Antimicrobial activity and MIC of the bromelain purified and crude fractions was studied against the test organisms. Peel crude and purified extract exhibited highest inhibitory effect towards S. aureus followed by P. acne. The antioxidant activity was evaluated using DPPH antioxidant assay. IC50 values peel, fruit, stem and crown are found to be 13.158 μg/ml, 24.13 μg/ml and 23.33 μg/ml and 113.79 μg/ml respectively. The purified bromelain from peel, stem and crown was used to create a facewash formulation towards pathogens frequently associated with skin infections. Common skin pathogens like S. aureus and P. acne were found highly sensitive to its action. The aim of this study was to evaluate the potential of bromelain isolated from waste parts of pineapple in alleviation of acne due to its diverse antimicrobial properties. [ABSTRACT FROM AUTHOR]
- Published
- 2021
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39. Forced temporal spiking timing stimulation to control frequency-specific oscillations in epileptic seizures: A computational study.
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Quinarez, Rachel Vital, Kothare, Mayuresh V., and Kumar, Gautam
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- 2023
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40. Dosing considerations for rufinamide in patients with Lennox-Gastaut syndrome: Phase III trial results and real-world clinical data.
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Kothare, Sanjeev, Kluger, Gerhard, Sachdeo, Rajesh, Williams, Betsy, Olhaye, Omar, Perdomo, Carlos, and Bibbiani, Francesco
- Abstract
Purpose: Lennox-Gastaut syndrome (LGS), a rare, severe form of childhood-onset epilepsy, is difficult to control. Rufinamide is indicated for adjunctive treatment of seizures associated with LGS in adults and pediatric patients aged ≥1 year. In clinical practice, rufinamide dosing and titration may differ from the trial setting. Here, rufinamide clinical trial data are compared with real-world experience to provide insight into optimal dosing and titration strategies.Methods: Rufinamide Phase III and open-label extension (OLE) studies were reviewed; effect of titration and dose on adverse events (AEs) and concomitant AED use were analyzed. Real-world studies of rufinamide in LGS were identified via PubMed search. Clinical data were extracted and compared.Results: Results demonstrated that a rapid titration schedule (7 or 14 days) of rufinamide was tolerable for most patients and resulted in highly significant reductions in total and tonic-atonic seizures, with efficacy and tolerability sustained over 3 years. The most common AEs during the Phase III study - somnolence, vomiting, and pyrexia - occurred during the first 3 weeks of treatment, and a small subset of patients were unable to reach target dose in that time. Use of concomitant AEDs had no clinically significant effect on plasma concentrations of rufinamide. Data from real-world clinical studies are consistent with the Phase III and OLE study results. However, relative to those used in clinical trials, lower doses and slower titration schedules were commonly employed in real-world settings.Conclusions: A lower dose and slower titration schedule ("low and slow") may reduce incidence of AEs without compromising efficacy of rufinamide in LGS. [ABSTRACT FROM AUTHOR]- Published
- 2017
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41. An improved system for simultaneous transcranial magnetic stimulation and single-unit recordings in non-human primates.
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Kothare, Raveena, Hamdan, Rena, Goetz, Stefan, Peterchev, Angel, and Sommer, Marc
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- 2023
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42. Predictors of seizure occurrence in children undergoing pre-surgical monitoring.
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Harini, Chellamani, Singh, Kanwaljit, Takeoka, Masanori, Parulkar, Isha, Bergin, Ann Marie, Loddenkemper, Tobias, and Kothare, Sanjeev V.
- Abstract
Abstract: Purpose: Long-Term-Monitoring (LTM) is a valuable tool for seizure localization/lateralization among children with refractory-epilepsy undergoing pre-surgical-monitoring. The aim of this study was to examine the factors predicting occurrence of single/multiple seizures in children undergoing pre-surgical monitoring in the LTM unit. Methods: Chart review was done on 95 consecutive admissions on 92 children (40 females) admitted to the LTM-unit for pre-surgical workup. Relationship between occurrence of multiple (≥3) seizures and factors such as home seizure-frequency, demographics, MRI-lesions/seizure-type and localization/AED usage/neurological-exam/epilepsy-duration was evaluated by logistic-regression and survival-analysis. Home seizure-frequency was further categorized into low (up-to 1/month), medium (up-to 1/week) and high (>1/week) and relationship of these categories to the occurrence of multiple seizures was evaluated. Mean length of stay was 5.24 days in all 3 groups. Results: Home seizure frequency was the only factor predicting the occurrence of single/multiple seizures in children undergoing presurgical workup. Other factors (age/sex/MRI-lesions/seizure-type and localization/AED-usage/neurological-exam/epilepsy-duration) did not affect occurrence of single/multiple seizures or time-to-occurrence of first/second seizure. Analysis of the home-seizure frequency categories revealed that 98% admissions in high-frequency, 94% in the medium, and 77% in low-frequency group had at-least 1 seizure recorded during the monitoring. Odds of first-seizure increased in high vs. low-frequency group (p =0.01). Eighty-nine percent admissions in high-frequency, 78% in medium frequency, versus 50% in low-frequency group had ≥3 seizures. The odds of having ≥3 seizures increased in high-frequency (p =0.0005) and in medium-frequency (p =0.007), compared to low-frequency group. Mean time-to-first-seizure was 2.7 days in low-frequency, 2.1 days in medium, and 2 days in high-frequency group. Time-to-first-seizure in high and medium-frequency was less than in low-frequency group (p <0.0014 and p =0.038). Conclusion: Majority of the admissions (92%) admitted to the LTM-unit for pre-surgical workup had at-least one seizure during a mean length of stay of 5.24 days. Home seizure-frequency was the only predictor influencing occurrence of single/multiple seizures in the LTM unit. Patients with low seizure-frequency are at risk for completing the monitoring with less than the optimum number (<3) of seizures captured. [Copyright &y& Elsevier]
- Published
- 2013
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43. Circadian patterns of generalized tonic-clonic evolutions in pediatric epilepsy patients.
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Ramgopal S, Vendrame M, Shah A, Gregas M, Zarowski M, Rotenberg A, Alexopoulos AV, Wyllie E, Kothare SV, and Loddenkemper T
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- 2012
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44. Output Feedback Controller Sparsification via H2-Approximation∗∗This research is supported by NSF-ECCS-1202517, AFOSR-YIP FA9550-13-1-0158, ONR N00014-13-1-0636, and NSF CAREER ECCS-1454022.
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Arastoo, R., Bahavarnia, M., Kothare, M.V., and Motee, N.
- Abstract
The problem of optimal sparse output feedback control design for continuous linear time invariant systems is considered. This work adopts the concept of %p-approximation to develop an optimization algorithm capable of synthesizing a structured sparse static controller gain for which the overall closed loop system exhibits empirical frequency characteristics resembling that of the system controlled with a pre-designed centralized controller. We, moreover, modify our optimization problem so that the control signal generated by the sparse controller falls into the vicinity of the centralized control input, in the sense of L norm. Furthermore, we show that our optimization problem can be equivalently reformulated into a rank constrained problem for which we propose to use a tailored version of Alternating Direction Method of Multipliers (ADMM) as a computationally efficient algorithm to sub-optimally solve it. Finally, we illuminate the effectiveness of our proposed method by testing it on randomly generated sample network models.
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- 2015
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45. An improved system for simultaneous transcranial magnetic stimulation and single-unit recordings in non-human primates.
- Author
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Kothare, Raveena, Goetz, Stefan, Hamdan, Rena, Wang, Boshuo, Grill, Warren, Peterchev, Angel, and Sommer, Marc
- Published
- 2021
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46. Should we be targeting the sleep–wake patterns of children with epilepsy?
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Jain, Sejal V and Kothare, Sanjeev V
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- 2011
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47. Model predictive control of nonlinear systems using piecewise linear models
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O¨zkan, Leyla, Kothare, Mayuresh V., and Georgakis, Christos
- Abstract
We consider the problem of controlling nonlinear systems which are modeled as a set of piecewise linear (PL) or affine systems using a model predictive control (MPC). The paper reviews recent results on the analysis and control of PL systems, which can model a wide range of practically relevant nonlinear systems. Using techniques from the theory of linear matrix inequalities (LMIs), we develop a multiple model MPC technique involving a sequence of local state feedback matrices, which minimize an upper bound on the 'worst-case' objective function. The resulting problem, which utilizes a single quadratic Lyapunov function and multiple local state-feedback matrices, can be cast as a convex optimization problem involving LMIs. Several extensions of this technique involving approximating the local regions by ellipsoids or polytopes, and their respective advantages and disadvantages, are discussed.
- Published
- 2000
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48. The Role of Phenytoin in the Treatment of Localization Related Epilepsy: An International Internet-Based Survey of Neurologists and Epileptologists
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Das, Rohit R., Griesemer, David A., and Kothare, Sanjeev V.
- Abstract
Phenytoin (PHT) has been the most widely used medication to treat both partial and generalized seizures. However, over the past twenty years, a variety of new compounds have been released with comparable efficacy, fewer adverse effects, and more predictable pharmacokinetic properties. We surveyed neurologists and epileptologists to determine current practice patterns relating to the use of PHT using an online survey instrument. A total of 200 responses were obtained though response rates for each survey question varied. Of the respondents, 78.1% were epilepsy specialists; 60% were adult practitioners; and the remainder saw either, only children or both adults and children. For new onset partial seizures only 10 respondents said PHT would be their first or second choice, while 45% reported that they would not consider PHT. This study shows that in the era of newer medications, the role of PHT has been placed in the category of a reserve medication in intractable epilepsy.
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- 2013
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49. An Uncommon Case of Pediatric Neurobrucellosis Associated with Intracranial Hypertension
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Sinopidis, Xenophon, Kaleyias, Joseph, Mitropoulou, Konstantina, Triga, Maria, Mantagos, Stefanos, and Kothare, Sanjeev Vithal
- Abstract
We present the case of a 4-year-old boy who was admitted to hospital with intracranial hypertension, headache, diplopia, papilledema, and a normal brain MRI. Brucella melitensis in the cerebrospinal fluid was confirmed with PCR assay. We believe that neurobrucellosis should be included in the differential diagnosis when headaches persist following brucellosis. In addition, we suggest that when cerebrospinal fluid culture is negative, PCR may prove to be an optimal alternative tool for an immediate and accurate diagnosis.
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- 2012
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50. Risk Factors Associated with Death in In-Hospital Pediatric Convulsive Status Epilepticus
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Loddenkemper, Tobias, Syed, Tanvir U., Ramgopal, Sriram, Gulati, Deepak, Thanaviratananich, Sikawat, Kothare, Sanjeev Vithal, Alshekhlee, Amer, and Koubeissi, Mohamad Z.
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Biology ,Population Biology ,Epidemiology ,Medicine ,Clinical Research Design ,Clinical Epidemiology ,Pediatric Epidemiology ,Neurology ,Epilepsy ,Temporal Lobe Epilepsy ,Tonic-Clonic Epilepsy ,Developmental and Pediatric Neurology ,Pediatrics - Abstract
Objective: To evaluate in-patient mortality and predictors of death associated with convulsive status epilepticus (SE) in a large, multi-center, pediatric cohort. Patients and Methods: We identified our cohort from the KID Inpatient Database for the years 1997, 2000, 2003 and 2006. We queried the database for convulsive SE, associated diagnoses, and for inpatient death. Univariate logistic testing was used to screen for potential risk factors. These risk factors were then entered into a stepwise backwards conditional multivariable logistic regression procedure. P-values less than 0.05 were taken as significant. Results: We identified 12,365 (5,541 female) patients with convulsive SE aged 0–20 years (mean age 6.2 years, standard deviation 5.5 years, median 5 years) among 14,965,571 pediatric inpatients (0.08%). Of these, 117 died while in the hospital (0.9%). The most frequent additional admission ICD-9 code diagnoses in addition to SE were cerebral palsy, pneumonia, and respiratory failure. Independent risk factors for death in patients with SE, assessed by multivariate calculation, included near drowning (Odds ratio [OR] 43.2; Confidence Interval [CI] 4.4–426.8), hemorrhagic shock (OR 17.83; CI 6.5–49.1), sepsis (OR 10.14; CI 4.0–25.6), massive aspiration (OR 9.1; CI 1.8–47), mechanical ventilation >96 hours (OR9; 5.6–14.6), transfusion (OR 8.25; CI 4.3–15.8), structural brain lesion (OR7.0; CI 3.1–16), hypoglycemia (OR5.8; CI 1.75–19.2), sepsis with liver failure (OR 14.4; CI 5–41.9), and admission in December (OR3.4; CI 1.6–4.1). African American ethnicity (OR 0.4; CI 0.2–0.8) was associated with a decreased risk of death in SE. Conclusion: Pediatric convulsive SE occurs in up to 0.08% of pediatric inpatient admissions with a mortality of up to 1%. There appear to be several risk factors that can predict mortality. These may warrant additional monitoring and aggressive management.
- Published
- 2012
- Full Text
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