73 results on '"Naveen K, Bansal"'
Search Results
2. Bayesian analysis of an M|M|1|∞ queueing model
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Naveen K. Bansal, V.S. Vaidyanathan, and P. Chandrasekhar
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Statistics and Probability ,Modeling and Simulation ,Management Science and Operations Research ,Statistics, Probability and Uncertainty - Abstract
In this paper, by considering an M|M|1|∞ queueing model, Bayes estimators of traffic intensity and measures of system performance are worked out under squared error loss function (SELF) based on observed data on the independent interarrival and service times. Further, minimum posterior risk associated with Bayes estimators of traffic intensity and system performance measures are obtained under SELF. Numerical illustration of the performance of the estimates is given through simulation study. It is shown that Bayes estimators perform better than the maximum likelihood estimators under the influence of prior information.
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- 2022
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3. Bayes estimation of autocorrelation coefficient
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Madhusudan Bhandary, Hongying Dai, Naveen K. Bansal, and Hyejin Shin
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- 2021
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4. Texture Consumption Patterns of 8- to 12-Month-Old Infants: A Reflection of Typical Feeding Development
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Sarah Staskiewicz, Praveen S. Goday, Megan Van Hoorn, Mary Beth Feuling, Amy L. Delaney, Naveen K. Bansal, and Stephanie Pladies
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Consumption (economics) ,Linguistics and Language ,business.industry ,Infant ,Nutritional Status ,Diet ,Speech and Hearing ,Cross-Sectional Studies ,Otorhinolaryngology ,Child, Preschool ,Developmental and Educational Psychology ,Humans ,Medicine ,Early childhood ,Child ,Energy Intake ,Infant Nutritional Physiological Phenomena ,business ,Demography - Abstract
PurposeThe lack of age-appropriate expectations for the acquisition of feeding skills and consumption of textured food in early childhood inhibits early and accurate identification of developmental delay in feeding and pediatric feeding disorder. The objective of this study was to describe texture intake patterns in a cohort of typically developing infants between 8 and 12 months of age, with the aim of informing future research to establish targets for feeding skill acquisition.MethodUsing cross-sectional methodology, we studied the presence of liquid and solid textures and drinking methods in the diet, consumption patterns by texture and drinking methods, and caloric intake by texture via caregiver questionnaire and 3-day dietary intake record in 63 healthy infants between 8 and 12 months of age. Descriptive statistics and a one-way analysis of variance were conducted to compare the effect of age on texture intake patterns.ResultsFindings reveal rapid advancement of intake patterns for texture overall and for energy intake by texture between 8 and 12 months of age. Whereas liquids continue to provide a large proportion of total energy through this time, solids contribute an equal proportion of energy by 12 months of age.ConclusionsThis study describes texture intake patterns in a cohort of typically developing infants between 8 and 12 months of age by examining the presence of texture and drinking methods, liquid and solid consumption patterns, and energy intake by texture. When applied to data from a future population sample, findings will provide a threshold for age expectations for typical and disordered feeding development to aid in the detection of developmental delay in feeding and pediatric feeding disorder.What Is Known:Expectations regarding early feeding development have been focused on nutrition parameters.Lack of standardized, age-appropriate expectations for texture progression in infancy and early childhood inhibits early and accurate identification and treatment of pediatric feeding disorder.What Is New:We have described changes in dietary composition by texture and drinking method in healthy infants.Together with nutritional composition, this study describes a more comprehensive assessment of infant feeding, particularly to clinicians who need to diagnose feeding skill deficits.Supplemental Materialhttps://doi.org/10.23641/asha.16879615
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- 2021
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5. An mCARE study on patterns of risk and resilience for children with ASD in Bangladesh
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Anik Iqbal, Dipranjan Das Dipal, Sheikh Iqbal Ahamed, Amy J. Schwichtenberg, Tanjir Rashid Soron, Munirul Haque, Naveen K. Bansal, Ishrak Islam Zarif, Syed Ishtiaque Ahmed, and Masud Rabbani
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Male ,Experience sampling method ,Activities of daily living ,Autism Spectrum Disorder ,Science ,Child Behavior ,Article ,Cohort Studies ,Social Skills ,Social skills ,Activities of Daily Living ,Human behaviour ,medicine ,Humans ,Child Care ,Child ,Bangladesh ,Multidisciplinary ,Aggression ,SARS-CoV-2 ,Communication ,Behavioral pattern ,COVID-19 ,medicine.disease ,Cell Phone Use ,Risk factors ,Autism spectrum disorder ,Child, Preschool ,Quarantine ,Autism ,Medicine ,Female ,medicine.symptom ,Psychology ,Sleep ,Self-Injurious Behavior ,Clinical psychology ,Cohort study - Abstract
Community-wide lockdowns in response to COVID-19 influenced many families, but the developmental cascade for children with autism spectrum disorder (ASD) may be especially detrimental. Our objective was to evaluate behavioral patterns of risk and resilience for children with ASD across parent-report assessments before (from November 2019 to February 2020), during (March 2020 to May 2020), and after (June 2020 to November 2020) an extended COVID-19 lockdown. In 2020, our study Mobile-based care for children with ASD using remote experience sampling method (mCARE) was inactive data collection before COVID-19 emerged as a health crisis in Bangladesh. Here we deployed “Cohort Studies”, where we had in total 300 children with ASD (150 test group and 150 control group) to collect behavioral data. Our data collection continued through an extended COVID-19 lockdown and captured parent reports of 30 different behavioral parameters (e.g., self-injurious behaviors, aggression, sleep problems, daily living skills, and communication) across 150 children with ASD (test group). Based on the children’s condition, 4–6 behavioral parameters were assessed through the study. A total of 56,290 behavioral data points was collected (an average of 152.19 per week) from parent cell phones using the mCARE platform. Children and their families were exposed to an extended COVID-19 lockdown. The main outcomes used for this study were generated from parent reports child behaviors within the mCARE platform. Behaviors included of child social skills, communication use, problematic behaviors, sensory sensitivities, daily living, and play. COVID-19 lockdowns for children with autism and their families are not universally negative but supports in the areas of “Problematic Behavior” could serve to mitigate future risk.
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- 2021
6. Bayes Estimation of Intraclass Correlation Coefficients Under Unequal Family Sizes.
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Naveen K. Bansal, Madhusudan Bhandary, and Koji Fujiwara
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- 2013
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7. A Bayesian decision theoretic approach to directional multiple hypotheses problems.
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Naveen K. Bansal and Klaus J. Miescke
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- 2013
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8. Modeling Temporal Pattern and Event Detection using Hidden Markov Model with Application to a Sludge Bulking Data.
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Naveen K. Bansal, Xin Feng, Wenjing Zhang, Wutao Wei, and Yuanhao Zhao
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- 2012
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9. The Decay of Disease Association with Declining Linkage Disequilibrium: A Fine Mapping Theorem
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Mehdi Maadooliat, Naveen K Bansal, Jiblal Upadhya, Manzur R. Farazi, Xiang Li, Scott J Hebbring, Max M He, Zhan Ye, and Steven J Schrodi
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Linkage Disequilibrium ,Association mapping ,Statistical Genetics/Genomics ,disease association ,Fine-mapping ,Mode of inheritance ,Genetics ,QH426-470 - Abstract
Several important and fundamental aspects of disease genetics models have yet to be described. One such property is the relationship of disease association statistics at a marker site closely linked to a disease causing site. A complete description of this two-locus system is of particular importance to experimental efforts to fine map association signals for complex diseases. Here, we present a simple relationship between disease association statistics and the decline of linkage disequilibrium from a causal site. Specifically, the ratio of Chi-square disease association statistics at a marker site and causal site is equivalent to the standard measure of pairwise linkage disequilibrium, r2. A complete derivation of this relationship from a general disease model is shown for very large sample sizes. Quite interestingly, this relationship holds across all modes of inheritance. Extensive Monte Carlo simulations using a disease genetics model applied to chromosomes subjected to a standard model of recombination are employed to better understand the variation around this fine mapping theorem due to sampling effects. We also use this relationship to provide a framework for estimating properties of a non-interrogated causal site using data at closely linked markers. Lastly, we apply this way of examining association data from high-density genotyping in a large, publicly-available data set investigating extreme BMI. We anticipate that understanding the patterns of disease association decay with declining linkage disequilibrium from a causal site will enable more powerful fine mapping methods and provide new avenues for identifying causal sites/genes from fine-mapping studies.
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- 2016
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10. An autoencoder and artificial neural network-based method to estimate parity status of wild mosquitoes from near-infrared spectra
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Marta F. Maia, Fredros O. Okumu, Nicodem J. Govella, Jacques D. Charlwood, Sheila B. Ogoma, Floyd E. Dowell, Masabho P. Milali, Serdar Bozdag, George F. Corliss, Maggy T. Sikulu-Lord, Samson S. Kiware, Richard J. Povinelli, and Naveen K. Bansal
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Veterinary medicine ,Physiology ,Anopheles Gambiae ,02 engineering and technology ,Disease Vectors ,Mosquitoes ,Spectrum Analysis Techniques ,Mathematical and Statistical Techniques ,0302 clinical medicine ,Statistics ,Medicine and Health Sciences ,0202 electrical engineering, electronic engineering, information engineering ,Protozoans ,Principal Component Analysis ,0303 health sciences ,Spectroscopy, Near-Infrared ,Multidisciplinary ,Artificial neural network ,Malarial Parasites ,Eukaryota ,near-Infrared Spectroscopy ,Body Fluids ,3. Good health ,Insects ,Ovaries ,Infectious Diseases ,Blood ,Oviparity ,qx_20 ,qx_510 ,Physical Sciences ,Medicine ,Female ,020201 artificial intelligence & image processing ,Nir spectra ,Anatomy ,Research Article ,Computer and Information Sciences ,Arthropoda ,Science ,030231 tropical medicine ,Infrared Spectroscopy ,Mosquito Vectors ,Biology ,Research and Analysis Methods ,03 medical and health sciences ,Artificial Intelligence ,Near infrared spectra ,Anopheles ,parasitic diseases ,Animals ,Humans ,Statistical Methods ,Artificial Neural Networks ,030304 developmental biology ,Computational Neuroscience ,Extramural ,Organisms ,Reproductive System ,Biology and Life Sciences ,Computational Biology ,equipment and supplies ,Invertebrates ,Autoencoder ,Parasitic Protozoans ,Insect Vectors ,Malaria ,Species Interactions ,Multivariate Analysis ,Neural Networks, Computer ,Parity (mathematics) ,Mathematics ,Neuroscience - Abstract
BackgroundAfter mating, female mosquitoes need animal blood to develop their eggs. In the process of acquiring blood, they may acquire pathogens, which may cause different diseases to humans such as malaria, zika, dengue, and chikungunya. Therefore, knowing the parity status of mosquitoes is useful in control and evaluation of infectious diseases transmitted by mosquitoes, where parous mosquitoes are assumed to be potentially infectious. Ovary dissections, which currently are used to determine the parity status of mosquitoes, are very tedious and limited to very few experts. An alternative to ovary dissections is near-infrared spectroscopy (NIRS), which can estimate the age in days and the infectious state of laboratory and semi-field reared mosquitoes with accuracies between 80 and 99%. No study has tested the accuracy of NIRS for estimating the parity status of wild mosquitoes.Methods and resultsIn this study, we train artificial neural network (ANN) models on NIR spectra to estimate the parity status of wild mosquitoes. We use four different datasets: An. arabiensis collected from Minepa, Tanzania (Minepa-ARA); An. gambiae collected from Muleba, Tanzania (Muleba-GA); An. gambiae collected from Burkina Faso (Burkina-GA); and An.gambiae from Muleba and Burkina Faso combined (Muleba-Burkina-GA). We train ANN models on datasets with spectra preprocessed according to previous protocols. We then use autoencoders to reduce the spectra feature dimensions from 1851 to 10 and re-train ANN models. Before the autoencoder was applied, ANN models estimated parity status of mosquitoes in Minepa-ARA, Muleba-GA, Burkina-GA and Muleba-Burkina-GA with out-of-sample accuracies of 81.9 ± 2.8% (N=927), 68.7 ± 4.8% (N=140), 80.3 ± 2.0% (N=158), and 75.7 ± 2.5% (N=298), respectively. With the autoencoder, ANN models tested on out-of-sample data achieved 97.1 ± 2.2%, (N=927), 89.8 ± 1.7% (N=140), 93.3 ± 1.2% (N=158), and 92.7 ± 1.8% (N=298) accuracies for Minepa-ARA, Muleba-GA, Burkina-GA, and Muleba-Burkina-GA, respectively.ConclusionThese results show that a combination of an autoencoder and an ANN trained on NIR spectra to estimate parity status of wild mosquitoes yields models that can be used as an alternative tool to estimate parity status of wild mosquitoes, especially since NIRS is a high-throughput, reagent-free, and simple-to-use technique compared to ovary dissections.
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- 2022
11. MENTAL IMAGERY PRACTICE AS A THERAPY FOR NAMING IMPAIRMENTS: A PRELIMINARY STUDY
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Bridget Patek, Naveen K. Bansal, Hugh W. Buckingham, Lotfi Hacein-Bey, Yasmeen Khan-Ansari, and Subhash C. Bhatnagar
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Neuropsychology and Physiological Psychology ,Psychology ,Applied Psychology ,Clinical psychology ,Mental image - Abstract
Anomia remains one of the most recalcitrant linguistic disruptions in aphasia to treat. Developing successful interventions to address the word-finding deficits are complicated by the post-stroke symptom variability and inconsistent recovery patterns associated with anomia. Most of the current treatment methods, with a focus on specific compensating techniques and the repetitive practice of a limited set of items, have had variable success in naming treatment. However, it has not been possible to predict the gains in generalizing the learning beyond the stimuli used in practice or the controlled clinical setting. In this preliminary case study, we explore the value of a novel treatment concept, grounded in centuries of cognitive-perceptual exercises in mindfulness training. It incorporates the practice of mental imagery and focused attention to remedy the broken phonological assembly patterns found in word finding deficits. The aim of this study was to evaluate the potential effectiveness of practicing the repeated activation of mental imagery of concrete objects as a therapeutic tool for repairing disorders of lexical retrieval in a subject with chronic moderate to severe word-finding deficits. This trial treatment was used to assist a right-handed, 68-year old educated male with a two-and-a-half years post-onset chronic severe aphasia (anomic type) secondary to a left hemispheric infarct. Two five-week long training protocols involving common (typical) and uncommon (less typical) categories of pictured objects were used for treating anomia. The first trial involved the blocked presentation of stimuli; the second trial, undertaken a year after, included a random presentation of stimuli. It was found that the impact was manifested in three ways: (1) an improved verbal naming of the treated objects; (2) retention of therapeutic gains by a successful generalization to untreated similar lexical items; and (3) importantly, serendipitous gains in the ability to concurrently write the names of the pictured objects. The post-treatment data on all blocked lexical trials, and some random lexical trials, were found to be significant on the Fisher’s exact test. The use of the visual mental imagery-based therapy had a positive impact on the partial restoration of the subject’s naming.
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- 2019
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12. Prevalence of molar-incisor hypomineralization in Milwaukee, Wisconsin, USA: a pilot study
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Rodney J. Vergotine, Cesar D. Gonzalez, Brian D. Hodgson, Christopher Okunseri, Lori Barbeau, Naveen K. Bansal, Andrew D Welles, Megan Davenport, and Matina V Angelopoulou
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medicine.medical_specialty ,Wisconsin usa ,Future studies ,business.industry ,0206 medical engineering ,Ethnic group ,Convenience sample ,030206 dentistry ,02 engineering and technology ,Paediatric dentistry ,Molar Incisor Hypomineralization ,020601 biomedical engineering ,03 medical and health sciences ,0302 clinical medicine ,Family medicine ,Medicine ,business ,General Dentistry ,Socioeconomic status ,School system - Abstract
Purpose: This pilot study investigated the prevalence of Molar-Incisor Hypomineralization (MIH) in third-grade school children in Milwaukee Wisconsin, USA. Methods: A convenience sample of third-grade school children in the Milwaukee Public School System (MPS) participated in the study. Calibrated examiners trained on the European Academy of Paediatric Dentistry (EAPD) MIH recommendations examined the children between December 1, 2014 and June 30, 2015. Children were examined at their schools using a flashlight and mirror after receiving consent from parents/caregivers and assent from each child. Findings were recorded onto a standardized form by one of five trained examiners. Summary statistics were calculated, and bivariate analysis were done to identify factors associated with MIH. Results: A total of 375 children (average age =8.66 years, range 7–12) were examined, 60% females and 41% Hispanics. Overall, 36 (9.6%) of the children demonstrated findings consistent with the diagnosis of MIH. Among the teeth with MIH defects, severe defects were higher in lower molars. There were no statistically significant differences between those with and without MIH by sex, race/ethnicity, and socioeconomic status in this study. Conclusion: The study revealed that 9.6% of the children examined were affected by MIH. Future studies should focus on statewide and/or nationwide surveys in the United States to ascertain the extent and severity of the condition.
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- 2019
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13. On Bayes Decision Rule for Testing Multiple Hypotheses with Non-symmetric Alternatives
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Mehdi Maadooliat, Naveen K. Bansal, and Soroush Mahmoudiandehkordi
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Statistics and Probability ,False discovery rate ,Discrete mathematics ,Alternative hypothesis ,05 social sciences ,Lebesgue integration ,01 natural sciences ,Constraint (information theory) ,Set (abstract data type) ,010104 statistics & probability ,Alpha (programming language) ,symbols.namesake ,Bayes' theorem ,Skewness ,0502 economics and business ,symbols ,050211 marketing ,0101 mathematics ,Mathematics - Abstract
We consider a multiple hypotheses testing problem with directional alternatives in a decision theoretic framework. Considering non-symmetric alternative hypotheses, we show that the skewness in the alternatives permits the Bayes rule to make more correct discoveries than if the alternatives are symmetric. We obtain a Bayes rule under a Lebesgue prior (non-informative) subject to a constraint on mixed directional false discovery rate $${\varvec{mdFDR}} \le {\varvec{\alpha}}$$ . The proposed Bayes rule is compared through simulation against rules proposed by Benjamini and Yekutieli (J Am Stat Assoc 100(469):71–80, 2005) and Efron (Ann Stat 35(4):1531–1377, 2007; J Am Stat Assoc 102(477):93–103, 2007). We illustrate the proposed methodology for two sets of data from biological experiments: HIV-transfected cell-line mRNA expression data and a quantitative trait genome-wide SNP data set.
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- 2021
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14. Informing Developmental Milestone Achievement for Children With Autism: Machine Learning Approach
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Anik Iqbal, Sheikh Iqbal Ahamed, Amy J. Schwichtenberg, Masud Rabbani, Munirul Haque, Dipranjan Das Dipal, Naveen K. Bansal, Syed Ishtiaque Ahmed, Tanjir Rashid Soron, and Ishrak Islam Zarif
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Experience sampling method ,autism spectrum disorders ,Computer applications to medicine. Medical informatics ,R858-859.7 ,digital health ,milestone parameters ,Health Informatics ,Machine learning ,computer.software_genre ,Autism and Developmental Disabilities Monitoring (ADDM) ,03 medical and health sciences ,0302 clinical medicine ,Health Information Management ,Milestone (project management) ,medicine ,0501 psychology and cognitive sciences ,mHealth ,mobile health ,Original Paper ,business.industry ,05 social sciences ,medicine.disease ,Child development ,mhealth ,early intervention ,machine learning ,Autism spectrum disorder ,Developmental Milestone ,Autism ,Unsupervised learning ,Artificial intelligence ,business ,Psychology ,computer ,predictive modeling ,030217 neurology & neurosurgery ,050104 developmental & child psychology - Abstract
Background Care for children with autism spectrum disorder (ASD) can be challenging for families and medical care systems. This is especially true in low- and- middle-income countries such as Bangladesh. To improve family–practitioner communication and developmental monitoring of children with ASD, mCARE (Mobile-Based Care for Children with Autism Spectrum Disorder Using Remote Experience Sampling Method) was developed. Within this study, mCARE was used to track child milestone achievement and family sociodemographic assets to inform mCARE feasibility/scalability and family asset–informed practitioner recommendations. Objective The objectives of this paper are threefold. First, it documents how mCARE can be used to monitor child milestone achievement. Second, it demonstrates how advanced machine learning models can inform our understanding of milestone achievement in children with ASD. Third, it describes family/child sociodemographic factors that are associated with earlier milestone achievement in children with ASD (across 5 machine learning models). Methods Using mCARE-collected data, this study assessed milestone achievement in 300 children with ASD from Bangladesh. In this study, we used 4 supervised machine learning algorithms (decision tree, logistic regression, K-nearest neighbor [KNN], and artificial neural network [ANN]) and 1 unsupervised machine learning algorithm (K-means clustering) to build models of milestone achievement based on family/child sociodemographic details. For analyses, the sample was randomly divided in half to train the machine learning models and then their accuracy was estimated based on the other half of the sample. Each model was specified for the following milestones: Brushes teeth, Asks to use the toilet, Urinates in the toilet or potty, and Buttons large buttons. Results This study aimed to find a suitable machine learning algorithm for milestone prediction/achievement for children with ASD using family/child sociodemographic characteristics. For Brushes teeth, the 3 supervised machine learning models met or exceeded an accuracy of 95% with logistic regression, KNN, and ANN as the most robust sociodemographic predictors. For Asks to use toilet, 84.00% accuracy was achieved with the KNN and ANN models. For these models, the family sociodemographic predictors of “family expenditure” and “parents’ age” accounted for most of the model variability. The last 2 parameters, Urinates in toilet or potty and Buttons large buttons, had an accuracy of 91.00% and 76.00%, respectively, in ANN. Overall, the ANN had a higher accuracy (above ~80% on average) among the other algorithms for all the parameters. Across the models and milestones, “family expenditure,” “family size/type,” “living places,” and “parent’s age and occupation” were the most influential family/child sociodemographic factors. Conclusions mCARE was successfully deployed in a low- and middle-income country (ie, Bangladesh), providing parents and care practitioners a mechanism to share detailed information on child milestones achievement. Using advanced modeling techniques this study demonstrates how family/child sociodemographic elements can inform child milestone achievement. Specifically, families with fewer sociodemographic resources reported later milestone attainment. Developmental science theories highlight how family/systems can directly influence child development and this study provides a clear link between family resources and child developmental progress. Clinical implications for this work could include supporting the larger family system to improve child milestone achievement.
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- 2021
15. Impact of Bio-Bubble on the Mental Health of Elite Cricketers during the COVID-19 Pandemic: The Bio-Bubble Fatigue
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Naveen K. Bansal and Shervin Sheriff
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History ,medicine.medical_specialty ,Polymers and Plastics ,Sports medicine ,biology ,media_common.quotation_subject ,Applied psychology ,biology.organism_classification ,Mental health ,Industrial and Manufacturing Engineering ,Feeling ,Cricket ,Rumination ,Pandemic ,medicine ,Introspection ,Tournament ,Business and International Management ,medicine.symptom ,Psychology ,media_common - Abstract
Ever since the resumption of cricket during COVID-19 pandemic, players and support staff have to stay in an isolated environment during the tournaments to prevent the risk of contracting COVID-19 from the external environment. This can have an adverse effect on the mental health of the players as they have to spend a lot of alone time, which can lead to introspection and rumination consisting of constant negative feelings. The authors evaluated media reports published between 1st July, 2020 and 31st May, 2021, on players withdrawing from a tournament midway or players who pulled out of an entire tournament citing bio-bubble fatigue (mental fatigue due to the bio-bubble environment) and found eight such cases. Mental fatigue builds in a cumulative manner, and therefore, more players are likely to suffer from bio-bubble fatigue during the next couple of months if this issue is not addressed. The authors recommend that every team must have a sports medicine physician/ sports psychologist at all times during the tournaments to make sure that the players remain mentally fit during this phase of COVID-19 pandemic.
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- 2021
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16. On the mixtures of Weibull and Pareto (IV) distribution: An alternative to Pareto distribution
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Gholamhossein G. Hamedani, Mehdi Maadooliat, Indranil Ghosh, and Naveen K. Bansal
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Statistics and Probability ,Finite mixture ,Distribution (number theory) ,Pareto principle ,Data application ,Mixture model ,01 natural sciences ,010104 statistics & probability ,symbols.namesake ,Expectation–maximization algorithm ,symbols ,Applied mathematics ,Pareto distribution ,0101 mathematics ,Mathematics ,Weibull distribution - Abstract
Finite mixture models have provided a reasonable tool to model various types of observed phenomena, specially those which are random in nature. In this article, a finite mixture of Weibull and Pareto (IV) distribution is considered and studied. Some structural properties of the resulting model are discussed including estimation of the model parameters via expectation maximization (EM) algorithm. A real-life data application exhibits the fact that in certain situations, this mixture model might be a better alternative than the rival popular models.
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- 2018
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17. Predoctoral Dental Students’ Perceptions of Dental Implant Training: Effect of Preclinical Simulation and Clinical Experience
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Soni Prasad and Naveen K. Bansal
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020205 medical informatics ,Attitude of Health Personnel ,Test group ,media_common.quotation_subject ,medicine.medical_treatment ,education ,Students, Dental ,Dentistry ,02 engineering and technology ,Simulation training ,03 medical and health sciences ,0302 clinical medicine ,Perception ,0202 electrical engineering, electronic engineering, information engineering ,medicine ,Humans ,Dental implant ,media_common ,Dental Implants ,Response rate (survey) ,Implant dentistry ,business.industry ,Teaching ,030206 dentistry ,General Medicine ,Training effect ,Patient Simulation ,Dental Implantation ,Clinical Competence ,Implant ,business - Abstract
The aims of this study were to assess 1) differences in perceptions of dental implant training between dental students who received didactic training alone (control group) and those who received didactic plus simulation training (test group); 2) differences in response between students with and without clinical experience in implant dentistry; and 3) the interaction effect of simulation training and clinical experience on students' satisfaction. A survey was distributed to the control group in 2014 and to the test group in 2015; both groups were at the same U.S. dental school. Data were collected on confidence levels with various implant restorative procedures along with overall satisfaction and number of implant restorations performed by each student. The response rate was 78.7% in the control group and 81.3% in the test group. In the control group, 85.7% of students reported being satisfied with implant training compared to 90.8% of students in the test group. The interaction effect of simulation training and clinical experience on overall student satisfaction was OR=1.5 at 95% CI: 0.8, 3.0. The students who had clinical experience with implant restorative procedures had significantly greater satisfaction than those who did not (OR=4.8, 95% CI: 2.1, 11.1, p
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- 2017
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18. Survivors of Chronic Stroke Experience Continued Impairment of Dexterity But Not Strength in the Nonparetic Upper Limb
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Kristen M. Triandafilou, Mary Ellen Stoykov, Naveen K. Bansal, Derek G. Kamper, Elliot J. Roth, and Alexander J. Barry
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Rehabilitation hospital ,Male ,030506 rehabilitation ,medicine.medical_specialty ,medicine.medical_treatment ,Physical Therapy, Sports Therapy and Rehabilitation ,Rehabilitation Centers ,Risk Assessment ,Article ,Cohort Studies ,Upper Extremity ,03 medical and health sciences ,Grip strength ,Disability Evaluation ,0302 clinical medicine ,Physical medicine and rehabilitation ,Reference Values ,medicine ,Humans ,cardiovascular diseases ,Survivors ,Jebsen-Taylor Hand Function Test ,Stroke ,Chronic stroke ,Aged ,Academic Medical Centers ,Rehabilitation ,Hand Strength ,business.industry ,Stroke Rehabilitation ,Middle Aged ,medicine.disease ,Prognosis ,Paresis ,medicine.anatomical_structure ,Cross-Sectional Studies ,Treatment Outcome ,Chronic Disease ,Exercise Test ,Upper limb ,Female ,0305 other medical science ,business ,030217 neurology & neurosurgery ,Cohort study - Abstract
OBJECTIVE: To investigate the performance of the less affected upper limb in people with stroke, compared to normative values. To examine less affected upper limb function in those whose pre-stroke dominant limb became paretic and those whose pre-stroke non-dominant limb became paretic. DESIGN: Cohort study of chronic stroke survivors (7.2±6.7 years post incident) SETTING: The study was performed at a freestanding academic rehabilitation hospital PARTICIPANTS: Forty chronic stroke survivors with severe hand impairment (Chedoke-McMaster Stroke Assessment rating of 2-3 on Stage of Hand) participated in the study. In 20 participants, the pre-stroke dominant hand (DH) was tested, (non-dominant hand affected by stroke), and in 20 participants the pre-stroke non-dominant hand (NH) was tested, (dominant hand affected by stroke). INTERVENTIONS: Not applicable MAIN OUTCOME MEASURE: Jebsen-Taylor Hand Function Test. Data from stroke survivors were compared with normative age- and gender-matched data from neurologically intact individuals. RESULTS: When combined, DH and NH groups performed significantly worse on fine motor tasks with their nonparetic hand relative to normative data (p0.140). CONCLUSIONS: Stroke survivors with severe impairment of the paretic limb continue to present significant upper extremity impairment in their nominally nonparetic limb even years after stroke. This phenomenon was observed regardless of whether the DH or NH hand was primarily affected. As this group of stroke survivors is especially dependent on the nonparetic limb for performing functional tasks, our results suggest that the nonparetic upper limb should be targeted for rehabilitation.
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- 2019
19. Implant Treatment in the Predoctoral Clinic: A Retrospective Database Study of 1091 Patients
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Soni Prasad, Arthur F. Hefti, Naveen K. Bansal, Eric Reigle, Katherine Sherman, and Christopher C. Hambrook
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medicine.medical_specialty ,020205 medical informatics ,business.industry ,medicine.medical_treatment ,Dental prosthesis ,Hazard ratio ,Dentistry ,Implant failure ,Retrospective cohort study ,030206 dentistry ,02 engineering and technology ,Crown (dentistry) ,Surgery ,03 medical and health sciences ,0302 clinical medicine ,Private practice ,0202 electrical engineering, electronic engineering, information engineering ,medicine ,Implant ,business ,General Dentistry ,Survival rate - Abstract
Purpose This retrospective study was conducted at the Marquette University School of Dentistry to (1) characterize the implant patient population in a predoctoral clinic, (2) describe the implants inserted, and (3) provide information on implant failures. Materials and Methods The study cohort included 1091 patients who received 1918 dental implants between 2004 and 2012, and had their implants restored by a crown or a fixed dental prosthesis. Data were collected from patient records, entered in a database, and summarized in tables and figures. Contingency tables were prepared and analyzed by a chi-squared test. The cumulative survival probability of implants was described using a Kaplan-Meier survival curve. Univariate and multivariate frailty Cox regression models for clustered observations were computed to identify factors associated with implant failure. Results Mean patient age (±1 SD) at implantation was 59.7 ± 15.3 years; 53.9% of patients were females, 73.5% were Caucasians. Noble Biocare was the most frequently used implant brand (65.0%). Most implants had a regular-size diameter (59.3%). More implants were inserted in posterior (79.0%) than in anterior jaw regions. Mandibular posterior was the most frequently restored site (43%); 87.8% of implants were restored using single implant crowns. The overall implant-based cumulative survival rate was 96.4%. The patient-based implant survival rate was 94.6%. Implant failure risk was greater among patients than within patients (p 65 years; hazard ratio [HR] = 3.2, p = 0.02), implant staging (two-stage; HR = 4.0, p < 0.001), and implant diameter (wide; HR = 0.4, p = 0.04) were statistically associated with implant failure. Conclusions Treatment with dental implants in a supervised predoctoral clinic environment resulted in survival rates similar to published results obtained in private practice or research clinics. Older age and implant staging increased failure risk, while the selection of a wide implant diameter was associated with a lower failure risk.
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- 2016
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20. Accuracy and precision of occlusal contacts of stereolithographic casts mounted by digital interocclusal registrations
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Jason T. Krahenbuhl, Naveen K. Bansal, Jon Patrick Irelan, and Seok-Hwan Cho
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Accuracy and precision ,Dental Impression Technique ,Siloxanes ,Articulator ,Dental Occlusion ,03 medical and health sciences ,0302 clinical medicine ,Occlusal contact ,Humans ,030223 otorhinolaryngology ,Mathematics ,Orthodontics ,Intraoral scanner ,Dental occlusion ,Dental Impression Materials ,Significant difference ,Radiography, Dental, Digital ,030206 dentistry ,Models, Dental ,Polyvinyl siloxane ,Jaw Relation Record ,Printing, Three-Dimensional ,Dental impression material ,Polyvinyls ,Oral Surgery ,Biomedical engineering - Abstract
Little peer-reviewed information is available regarding the accuracy and precision of the occlusal contact reproduction of digitally mounted stereolithographic casts.The purpose of this in vitro study was to evaluate the accuracy and precision of occlusal contacts among stereolithographic casts mounted by digital occlusal registrations.Four complete anatomic dentoforms were arbitrarily mounted on a semi-adjustable articulator in maximal intercuspal position and served as the 4 different simulated patients (SP). A total of 60 digital impressions and digital interocclusal registrations were made with a digital intraoral scanner to fabricate 15 sets of mounted stereolithographic (SLA) definitive casts for each dentoform. After receiving a total of 60 SLA casts, polyvinyl siloxane (PVS) interocclusal records were made for each set. The occlusal contacts for each set of SLA casts were measured by recording the amount of light transmitted through the interocclusal records. To evaluate the accuracy between the SP and their respective SLA casts, the areas of actual contact (AC) and near contact (NC) were calculated. For precision analysis, the coefficient of variation (CoV) was used. The data was analyzed with t tests for accuracy and the McKay and Vangel test for precision (α=.05).The accuracy analysis showed a statistically significant difference between the SP and the SLA cast of each dentoform (P.05). For the AC in all dentoforms, a significant increase was found in the areas of actual contact of SLA casts compared with the contacts present in the SP (P.05). Conversely, for the NC in all dentoforms, a significant decrease was found in the occlusal contact areas of the SLA casts compared with the contacts in the SP (P.05). The precision analysis demonstrated the different CoV values between AC (5.8 to 8.8%) and NC (21.4 to 44.6%) of digitally mounted SLA casts, indicating that the overall precision of the SLA cast was low.For the accuracy evaluation, statistically significant differences were found between the occlusal contacts of all digitally mounted SLA casts groups, with an increase in AC values and a decrease in NC values. For the precision assessment, the CoV values of the AC and NC showed the digitally articulated cast's inability to reproduce the uniform occlusal contacts.
- Published
- 2016
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21. An Online Educational Program Improves Pediatric Oncology Nurses’ Knowledge, Attitudes, and Spiritual Care Competence
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Margaret Faut Callahan, Naveen K. Bansal, Rosemary White-Traut, Donna O. McCarthy, Cheryl L. Petersen, and Ronda G. Hughes
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Adult ,Male ,Health Knowledge, Attitudes, Practice ,Nurses knowledge ,Nurse's Role ,Pediatrics ,Spiritual Therapies ,03 medical and health sciences ,0302 clinical medicine ,Nursing ,Neoplasms ,Pediatric oncology ,Humans ,Medicine ,Prospective Studies ,030212 general & internal medicine ,Child ,Competence (human resources) ,Potential impact ,030504 nursing ,Oncology (nursing) ,business.industry ,Oncology Nursing ,Pediatric Nursing ,Oncology nursing ,Female ,Spiritual care ,Pediatric nursing ,0305 other medical science ,business ,Educational program ,Computer-Assisted Instruction - Abstract
This study evaluated the potential impact of an online spiritual care educational program on pediatric nurses’ attitudes toward and knowledge of spiritual care and their competence to provide spiritual care to children with cancer at the end of life. It was hypothesized that the intervention would increase nurses’ positive attitudes toward and knowledge of spiritual care and increase nurses’ level of perceived spiritual care competence. A positive correlation was expected between change in nurses’ perceived attitudes toward and knowledge of spiritual care and change in nurses’ perceived spiritual care competence. A prospective, longitudinal design was employed, and analyses included one-way repeated-measures analysis of variance, linear regression, and partial correlation. Statistically significant differences were found in nurses’ attitudes toward and knowledge of spiritual care and nurses’ perceived spiritual care competence. There was a positive relationship between change scores in nurses’ attitudes toward and knowledge of spiritual care and nurses’ spiritual care competence. Online spiritual care educational programs may exert a lasting impact on nurses’ attitudes toward and knowledge of spiritual care and their competence to provide spiritual care to children with cancer at the end of life. Additional studies are required to evaluate the direct effects of educational interventions patient outcomes.
- Published
- 2016
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22. Prevalence of molar-incisor hypomineralization in Milwaukee, Wisconsin, USA: a pilot study
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Megan, Davenport, Andrew D, Welles, Matina V, Angelopoulou, Cesar, Gonzalez, Christopher, Okunseri, Lori, Barbeau, Naveen K, Bansal, Rodney J, Vergotine, and Brian D, Hodgson
- Subjects
molar incisor hypomineralization ,children ,prevalence ,MIH ,United States ,Original Research - Abstract
Purpose: This pilot study investigated the prevalence of Molar-Incisor Hypomineralization (MIH) in third-grade school children in Milwaukee Wisconsin, USA. Methods: A convenience sample of third-grade school children in the Milwaukee Public School System (MPS) participated in the study. Calibrated examiners trained on the European Academy of Paediatric Dentistry (EAPD) MIH recommendations examined the children between December 1, 2014 and June 30, 2015. Children were examined at their schools using a flashlight and mirror after receiving consent from parents/caregivers and assent from each child. Findings were recorded onto a standardized form by one of five trained examiners. Summary statistics were calculated, and bivariate analysis were done to identify factors associated with MIH. Results: A total of 375 children (average age =8.66 years, range 7–12) were examined, 60% females and 41% Hispanics. Overall, 36 (9.6%) of the children demonstrated findings consistent with the diagnosis of MIH. Among the teeth with MIH defects, severe defects were higher in lower molars. There were no statistically significant differences between those with and without MIH by sex, race/ethnicity, and socioeconomic status in this study. Conclusion: The study revealed that 9.6% of the children examined were affected by MIH. Future studies should focus on statewide and/or nationwide surveys in the United States to ascertain the extent and severity of the condition.
- Published
- 2018
23. Empirical Bayesian approach to testing multiple hypotheses with separate priors for left and right alternatives
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Mehdi Maadooliat, Steven J. Schrodi, and Naveen K. Bansal
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0301 basic medicine ,Statistics and Probability ,False discovery rate ,Computer science ,Bayesian probability ,HIV Infections ,Machine learning ,computer.software_genre ,Polymorphism, Single Nucleotide ,01 natural sciences ,010104 statistics & probability ,03 medical and health sciences ,Bayes' theorem ,Prior probability ,Expectation–maximization algorithm ,Genetics ,Test statistic ,Humans ,0101 mathematics ,Molecular Biology ,Parametric statistics ,Models, Statistical ,Models, Genetic ,Waist-Hip Ratio ,business.industry ,Nonparametric statistics ,Bayes Theorem ,Computational Mathematics ,030104 developmental biology ,Female ,Artificial intelligence ,business ,Monte Carlo Method ,computer ,Algorithms ,Software ,Genome-Wide Association Study - Abstract
We consider a multiple hypotheses problem with directional alternatives in a decision theoretic framework. We obtain an empirical Bayes rule subject to a constraint on mixed directional false discovery rate (mdFDR≤α) under the semiparametric setting where the distribution of the test statistic is parametric, but the prior distribution is nonparametric. We proposed separate priors for the left tail and right tail alternatives as it may be required for many applications. The proposed Bayes rule is compared through simulation against rules proposed by Benjamini and Yekutieli and Efron. We illustrate the proposed methodology for two sets of data from biological experiments: HIV-transfected cell-line mRNA expression data, and a quantitative trait genome-wide SNP data set. We have developed a user-friendly web-based shiny App for the proposed method which is available through URL https://npseb.shinyapps.io/npseb/. The HIV and SNP data can be directly accessed, and the results presented in this paper can be executed.
- Published
- 2018
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24. Constrained Bayesian Method for Testing the Directional Hypotheses
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Kartlos J. Kachiashvili, Naveen K. Bansal, and I. A. Prangishvili
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False discovery rate ,Computer science ,business.industry ,Bayesian probability ,Artificial intelligence ,Machine learning ,computer.software_genre ,business ,computer ,Statistical hypothesis testing - Published
- 2018
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25. Testing multiple hypotheses with skewed alternatives
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Gholamhossein G. Hamedani, Mehdi Maadooliat, and Naveen K. Bansal
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0301 basic medicine ,Statistics and Probability ,False discovery rate ,Mathematical optimization ,General Immunology and Microbiology ,Skew normal distribution ,Applied Mathematics ,Bayesian probability ,General Medicine ,01 natural sciences ,General Biochemistry, Genetics and Molecular Biology ,Constraint (information theory) ,010104 statistics & probability ,03 medical and health sciences ,Bayes' theorem ,030104 developmental biology ,Frequentist inference ,A priori and a posteriori ,0101 mathematics ,General Agricultural and Biological Sciences ,Statistical hypothesis testing ,Mathematics - Abstract
In many practical cases of multiple hypothesis problems, it can be expected that the alternatives are not symmetrically distributed. If it is known a priori that the distributions of the alternatives are skewed, we show that this information yields high power procedures as compared to the procedures based on symmetric alternatives when testing multiple hypotheses. We propose a Bayesian decision theoretic rule for multiple directional hypothesis testing, when the alternatives are distributed as skewed, under a constraint on a mixed directional false discovery rate. We compare the proposed rule with a frequentist's rule of Benjamini and Yekutieli (2005) using simulations. We apply our method to a well-studied HIV dataset.
- Published
- 2015
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26. A Bayesian methodology for detecting targeted genes under two related experiments
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Prachi Pradeep, Hongmei Jiang, and Naveen K. Bansal
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Statistics and Probability ,False discovery rate ,Bayes' theorem ,Epidemiology ,Computer science ,Bayesian probability ,Expectation–maximization algorithm ,Multiple hypotheses ,Data mining ,Computational biology ,computer.software_genre ,computer ,Gene - Abstract
Many gene expression data are based on two experiments where the gene expressions of the targeted genes under both experiments are correlated. We consider problems in which objectives are to find genes that are simultaneously upregulated/downregulated under both experiments. A Bayesian methodology is proposed based on directional multiple hypotheses testing. We propose a false discovery rate specific to the problem under consideration, and construct a Bayes rule satisfying a false discovery rate criterion. The proposed method is compared with a traditional rule through simulation studies. We apply our methodology to two real examples involving microRNAs; where in one example the targeted genes are simultaneously downregulated under both experiments, and in the other the targeted genes are downregulated in one experiment and upregulated in the other experiment. We also discuss how the proposed methodology can be extended to more than two experiments.
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- 2015
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27. Hypothesis Testing for High-Dimensional Problems
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Naveen K. Bansal
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False discovery rate ,Skew normal distribution ,Computer science ,Familywise error rate ,High dimensional ,Algorithm ,GeneralLiterature_REFERENCE(e.g.,dictionaries,encyclopedias,glossaries) ,Statistical hypothesis testing - Published
- 2017
28. Interproximal distance analysis of stereolithographic casts made by CAD-CAM technology: An in vitro study
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Melanie Hoffman, Seok-Hwan Cho, and Naveen K. Bansal
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Dental Impression Technique ,Stereolithography ,Materials science ,medicine.medical_treatment ,0206 medical engineering ,Dentistry ,02 engineering and technology ,In Vitro Techniques ,Mandibular first molar ,Crown (dentistry) ,03 medical and health sciences ,Maxillary left central incisor ,0302 clinical medicine ,medicine ,Premolar ,Humans ,In vitro study ,Dental Casting Technique ,Crowns ,business.industry ,Dental prosthesis ,030206 dentistry ,020601 biomedical engineering ,Polyvinyl siloxane ,medicine.anatomical_structure ,Dental Prosthesis Design ,Computer-Aided Design ,Distance analysis ,Oral Surgery ,business - Abstract
The accuracy of interproximal distances of the definitive casts made by computer-aided design and computer-aided manufacturing (CAD-CAM) technology is not yet known.The purpose of this in vitro study was to compare the interproximal distances of stereolithographic casts made by CAD-CAM technology with those of stone casts made by the conventional method.Dentoform teeth were prepared for a single ceramic crown on the maxillary left central incisor, a 3-unit fixed dental prosthesis (FDP) on the second premolar for a metal-ceramic crown, and a maxillary right first molar for a metal crown. Twenty digital intraoral impressions were made on the dentoform with an intraoral digital impression scanner. The digital impression files were used to fabricate 20 sets of stereolithographic casts, 10 definitive casts for the single ceramic crown, and 10 definitive casts for the FDP. Furthermore, 20 stone casts were made by the conventional method using polyvinyl siloxane impression material with a custom tray. Each definitive cast for stereolithographic cast and stone cast consisted of removable die-sectioned casts (DC) and nonsectioned solid casts (SC). Measurements of interproximal distance of each cast were made using CAD software to provide mean ±standard deviation (SD) values. Data were first analyzed by repeated measures analysis of variance (ANOVA), using different methods of cast fabrication (stone and stereolithography) as one within subject factor and different cast types (DC and SC) as another within subject factor. Post hoc analyses were performed to investigate the differences between stone and stereolithographic casts depending upon the results from the repeated measures ANOVA (α=.05).Analysis of interproximal distances showed the mean ±SD value of the single ceramic crown group was 31.2 ±24.5 μm for stone casts and 261.0 ±116.1 μm for stereolithographic casts, whereas the mean ±SD value for the FDP group was 46.0 ±35.0 μm for stone casts and 292.8 ±216.6 μm for stereolithographic casts. For both the single ceramic crown and the FDP groups, there were significant differences in interproximal distances between stereolithographic casts and stone casts (P.001). In addition, the comparisons of DC with SC of stone and stereolithographic casts for the single ceramic crown and FDP groups demonstrated there was statistically significant differences among interproximal distances between DC stereolithographic casts and SC stereolithographic casts only for the FDP group (P.001).For both the single ceramic crown and the FDP groups, the stereolithographic cast group showed significantly larger interproximal distances than the stone cast group. In terms of the comparison between DC and SC, DC stereolithographic casts for the FDP group only showed significantly larger interproximal values than those of the SC stereolithographic casts for the FDP group.
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- 2017
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29. Deficits of the Nonparetic Upper Limb in Chronic Stroke Survivors
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Elliot J. Roth, Kristen M. Triandafilou, Mary Ellen Stoykov, Alexander J. Barry, Derek G. Kamper, and Naveen K. Bansal
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medicine.medical_specialty ,Physical medicine and rehabilitation ,medicine.anatomical_structure ,business.industry ,Rehabilitation ,medicine ,Upper limb ,Physical Therapy, Sports Therapy and Rehabilitation ,business ,Chronic stroke - Published
- 2019
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30. The Pitman inequality for exchangeable random vectors
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Gholamhossein G. Hamedani, Hans Volkmer, Naveen K. Bansal, and Javad Behboodian
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Statistics and Probability ,Combinatorics ,Characteristic function (probability theory) ,Inequality ,Multivariate random variable ,media_common.quotation_subject ,Mathematical analysis ,Log sum inequality ,Rearrangement inequality ,Statistics, Probability and Uncertainty ,Symmetry (geometry) ,Mathematics ,media_common - Abstract
In this short article the following inequality called the “Pitman inequality” is proved for the exchangeable random vector ( X 1 , X 2 , … , X n ) without the assumption of continuity and symmetry for each component X i : P ( | 1 n ∑ i = 1 n X i | ≤ | ∑ i = 1 n α i X i | ) ≥ 1 2 , where all α i ≥ 0 are special weights with ∑ i = 1 n α i = 1 .
- Published
- 2013
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31. The Decay of Disease Association with Declining Linkage Disequilibrium: A Fine Mapping Theorem
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Naveen K. Bansal, Manzur R. Farazi, Mehdi Maadooliat, Zhan Ye, Steven J. Schrodi, Scott J. Hebbring, Jiblal Upadhya, Xiang Li, and Max M. He
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0301 basic medicine ,Linkage disequilibrium ,lcsh:QH426-470 ,Association (object-oriented programming) ,Disease Association ,Disease ,Biology ,03 medical and health sciences ,Hypothesis and Theory ,two-site model ,Genetics ,Association mapping ,Genetics (clinical) ,statistical genetics/genomics ,disease association ,Inheritance (genetic algorithm) ,Sampling (statistics) ,mode of inheritance ,Data set ,lcsh:Genetics ,030104 developmental biology ,fine-mapping ,Evolutionary biology ,theoretical genetics ,Molecular Medicine ,disease genetics ,linkage disequilibrium - Abstract
Several important and fundamental aspects of disease genetics models have yet to be described. One such property is the relationship of disease association statistics at a marker site closely linked to a disease causing site. A complete description of this two-locus system is of particular importance to experimental efforts to fine map association signals for complex diseases. Here, we present a simple relationship between disease association statistics and the decline of linkage disequilibrium from a causal site. Specifically, the ratio of Chi-square disease association statistics at a marker site and causal site is equivalent to the standard measure of pairwise linkage disequilibrium, r2. A complete derivation of this relationship from a general disease model is shown for very large sample sizes. Quite interestingly, this relationship holds across all modes of inheritance. Extensive Monte Carlo simulations using a disease genetics model applied to chromosomes subjected to a standard model of recombination are employed to better understand the variation around this fine mapping theorem due to sampling effects. We also use this relationship to provide a framework for estimating properties of a non-interrogated causal site using data at closely linked markers. Lastly, we apply this way of examining association data from high-density genotyping in a large, publicly-available data set investigating extreme BMI. We anticipate that understanding the patterns of disease association decay with declining linkage disequilibrium from a causal site will enable more powerful fine mapping methods and provide new avenues for identifying causal sites/genes from fine-mapping studies.
- Published
- 2016
32. The Decay of Disease Association with Declining Linkage Disequilibrium: A Fine Mapping Theorem
- Author
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Steven J. Schrodi, Manzur R. Farazi, Mehdi Maadooliat, Zhan Ye, Jiblal Upadhya, Naveen K. Bansal, and Xiang Li
- Subjects
0303 health sciences ,03 medical and health sciences ,Linkage disequilibrium ,Evolutionary biology ,Association (object-oriented programming) ,030305 genetics & heredity ,Inheritance (genetic algorithm) ,Disease Association ,Sampling (statistics) ,Disease ,Biology ,030304 developmental biology ,Large sample - Abstract
Several important and fundamental aspects of disease genetics models have yet to be described. One such property is the relationship of disease association statistics at a marker site closely linked to a disease causing site. A complete description of this two-locus system is of particular importance to experimental efforts to fine map association signals for complex diseases. Here, we present a simple relationship between disease association statistics and the decline of linkage disequilibrium from a causal site. A complete derivation of this relationship from a general disease model is shown for very large sample sizes. Quite interestingly, this relationship holds across all modes of inheritance. Extensive Monte Carlo simulations using a disease genetics model applied to chromosomes subjected to a standard model of recombination are employed to better understand the variation around this fine mapping theorem due to sampling effects. We also use this relationship to provide a framework for estimating properties of a non-interrogated causal site using data at closely linked markers. We anticipate that understanding the patterns of disease association decay with declining linkage disequilibrium from a causal site will enable more powerful fine mapping methods.
- Published
- 2016
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33. Bayesian analysis of hypothesis testing problems for general population: A Kullback–Leibler alternative
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Gholamhossein G. Hamedani, Ru Sheng, and Naveen K. Bansal
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Statistics and Probability ,education.field_of_study ,Mathematical optimization ,Kullback–Leibler divergence ,Applied Mathematics ,Population ,Bayesian probability ,Bayes factor ,Statistics::Computation ,Bayesian statistics ,Bayesian experimental design ,Econometrics ,Statistics, Probability and Uncertainty ,education ,Bayesian average ,Mathematics ,Statistical hypothesis testing - Abstract
We consider a hypothesis problem with directional alternatives. We approach the problem from a Bayesian decision theoretic point of view and consider a situation when one side of the alternatives is more important or more probable than the other. We develop a general Bayesian framework by specifying a mixture prior structure and a loss function related to the Kullback–Leibler divergence. This Bayesian decision method is applied to Normal and Poisson populations. Simulations are performed to compare the performance of the proposed method with that of a method based on a classical z-test and a Bayesian method based on the “0–1” loss.
- Published
- 2012
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34. Bayesian decision theoretic approach to hypothesis problems with skewed alternatives
- Author
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Ru Sheng and Naveen K. Bansal
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Statistics and Probability ,Mathematical optimization ,Applied Mathematics ,Decision theory ,Bayesian probability ,Type III error ,Bayes' theorem ,Frequentist inference ,Prior probability ,Parametric model ,Econometrics ,Statistics, Probability and Uncertainty ,Statistical hypothesis testing ,Mathematics - Abstract
Many hypothesis problems in practice require the selection of the left side or the right side alternative when the null is rejected. For parametric models, this problem can be stated as H 0 : θ = θ 0 vs. H − : θ θ 0 or H + : θ > θ 0 . Frequentists use Type-III error (directional error) to develop statistical methodologies. This approach and other approaches considered in the literature do not take into account the situations where the selection of one side may be more important or when one side may be more probable than the other. This problem can be tackled by specifying a loss function and/or by specifying a hierarchical prior structure with allowing the skewness in the alternatives. Based on this, we develop a Bayesian decision theoretic methodology and show that the resulted Bayes rule perform better in the side of the alternatives which is more probable. The methodology can be also used in a frequentist's framework when it is desired to discover an alternative that is more important. We also consider the multiple hypotheses problem and develop new false discovery rates for the selection of the left and the right sides of alternatives. These discovery rates would be useful in the situations when one side of the alternatives are more important or more probable than the other.
- Published
- 2010
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35. Creating Composite Age Groups to Smooth Percentile Rank Distributions of Small Samples
- Author
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Francesca López, Amy M. Olson, and Naveen K. Bansal
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Ordinal data ,media_common.quotation_subject ,Sample (statistics) ,Education ,Clinical Psychology ,Percentile rank ,Moving average ,Sample size determination ,Statistics ,Econometrics ,Raw score ,Thurstone scale ,General Psychology ,Normality ,Mathematics ,media_common - Abstract
Individually administered tests are often normed on small samples, a process that may result in irregularities within and across various age or grade distributions. Test users often smooth distributions guided by Thurstone assumptions (normality and linearity) to result in norms that adhere to assumptions made about how the data should look. Test users, however, may come across particular tests or sets of data in which the Thurstone assumptions are untenable. When users expect deviations from normality within age or grade, an alternate method is desirable. The authors present a relatively simple procedure that allows the user to treat observed raw scores as ordinal data with differently shaped sample distributions across age levels. Each age-level group is used twice to create new moving composite group distributions that replace (i.e., smooth) the original groups to reduce irregularities due to the small sample sizes. The authors present the results of a simulation study of the method, demonstrating that moving composite groups ameliorate error introduced by small samples beyond applying the normalized inverse to a score distribution. The method presented might satisfy those who question whether their data meet the strong assumptions of normality and interval-level measurement, and the simplicity might encourage smoothing by additional users.
- Published
- 2010
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36. An Application of EM Algorithm to a Change-Point Problem
- Author
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Hong Du, Naveen K. Bansal, and G. G. Hamedani
- Subjects
Statistics and Probability ,Distribution (mathematics) ,Distribution function ,Exponential family ,Bayesian probability ,Expectation–maximization algorithm ,Calculus ,Probability distribution ,Point (geometry) ,Algorithm ,Mathematics ,Statistical hypothesis testing - Abstract
We consider the problem of change-point in a classical framework while assuming a probability distribution for the change-point. An EM algorithm is proposed to estimate the distribution of the change-point. A change-point model for multiple profiles is also proposed, and EM algorithm is presented to estimate the model. Two examples of Illinois traffic data and Dow Jones Industrial Averages are used to demonstrate the proposed methods.
- Published
- 2008
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37. Empirical Bayes and Hierarchical Bayes Estimation of Skew Normal Populations
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Naveen K. Bansal, Mehdi Maadooliat, and Xiaowei Wang
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Statistics and Probability ,Skew normal distribution ,Skew ,Statistics::Computation ,Normal distribution ,symbols.namesake ,Bayes' theorem ,Skewness ,Expectation–maximization algorithm ,Statistics ,symbols ,Bayesian hierarchical modeling ,Mathematics ,Gibbs sampling - Abstract
We develop empirical and hierarchical Bayesian methodologies for the skew normal populations through the EM algorithm and the Gibbs sampler. A general concept of skewness to the normal distribution is considered throughout. Motivations are given for considering the skew normal population in applications, and an example is presented to demonstrate why the skew normal distribution is more applicable than the normal distribution for certain applications.
- Published
- 2008
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38. Effect of reflux-induced inflammation on transient receptor potential vanilloid one (TRPV1) expression in primary sensory neurons innervating the oesophagus of rats
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Jyoti N. Sengupta, Banani Banerjee, Bidyut K. Medda, Reza Shaker, Naveen K. Bansal, and Zelmira Lazarova
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Male ,medicine.medical_specialty ,Physiology ,TRPV1 ,TRPV Cation Channels ,Substance P ,Inflammation ,Rats, Sprague-Dawley ,chemistry.chemical_compound ,Transient receptor potential channel ,Esophagus ,Ganglia, Spinal ,Internal medicine ,medicine ,Animals ,Neurons, Afferent ,Endocrine and Autonomic Systems ,Chemistry ,Gastroenterology ,Colocalization ,Nodose Ganglion ,Spinal cord ,Immunohistochemistry ,Rats ,Disease Models, Animal ,Endocrinology ,medicine.anatomical_structure ,nervous system ,Anesthesia ,Gastroesophageal Reflux ,lipids (amino acids, peptides, and proteins) ,Plant Lectins ,medicine.symptom ,psychological phenomena and processes - Abstract
A possible mechanism of oesophageal hypersensitivity is the acid-induced activation of transient receptor potential vanilloid receptor 1 (TRPV1) in the primary sensory neurons. We investigated TRPV1 expression and its colocalization with substance P (SP) and isolectin B4 (IB4)-positive cells in the thoracic dorsal root ganglia (DRGs) and nodose ganglia (NGs) of rats with reflux-induced oesophagitis (RO). RO was developed by fundus ligation and partial obstruction of the pylorus of Sprague-Dawley rats. Four groups of rats were used; fundus ligated acute (RO 48 h), chronic 7 days (RO 7D), RO 7D + omeprazole (7D + Omz, 40 mg kg−1, i.p.) and sham-operated controls. Immunohistochemical analysis of TRPV1, SP and IB4 expression were carried out in spinal cord (SC), DRGs and NGs. RO rats exhibited significant inflammation and increase in TRPV1-ir and SP-ir expressions in the SC, DRGs and NGs. The maximum colocalization of TRPV1 and SP was observed in RO 7D rats, but Omz prevented inflammation and over expression of TRPV1 and SP. TRPV1-ir significantly increased in IB4-positive cells in DRGs and SC, but not in the NGs. Results document that acid-induced oesophagitis increases TRPV1 expression in both SP- and IB4-positive sensory neurons. The over expression of TRPV1 may contribute to oesophageal hypersensitivity observed in gastro-oesophageal reflux disease (GORD).
- Published
- 2007
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39. On selecting the best treatment in a generalized linear model
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Naveen K. Bansal and Klaus J. Miescke
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Statistics and Probability ,Generalized linear model ,Applied Mathematics ,Linear model ,Bayes' theorem ,symbols.namesake ,Laplace's method ,Prior probability ,Calculus ,symbols ,Nuisance parameter ,Applied mathematics ,Statistics, Probability and Uncertainty ,Invariant (mathematics) ,Mathematics ,Gibbs sampling - Abstract
The problem of selecting the best treatment is studied under generalized linear models. For certain balanced designs, it is shown that simple rules are Bayes with respect to any non-informative prior on the treatment effects under any monotone invariant loss. When the nuisance parameters such as block effects are assumed to follow a uniform (improper) prior or a normal prior, Bayes rules are obtained for the normal linear model under more suitable balanced designs, keeping the generality of the loss and the generality of the non-informativeness on the prior of the treatment effects. These results are extended to certain types of informative priors on the treatment effects. When the designs are unbalanced, algorithms based on the Gibbs sampler and the Laplace method are provided to compute the Bayes rules.
- Published
- 2006
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40. Simultaneous selection and estimation of the best treatment with respect to a control in a general linear model
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Naveen K. Bansal and Klaus J. Miescke
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Statistics and Probability ,General linear model ,Bayes' theorem ,Mathematical optimization ,Estimation theory ,Applied Mathematics ,Prior probability ,Linear model ,Function (mathematics) ,Decision rule ,Statistics, Probability and Uncertainty ,Selection (genetic algorithm) ,Mathematics - Abstract
The problem of selecting the largest treatment parameter, provided it is better than a control, and simultaneously estimating the selected treatment parameter in a general linear model is considered in the decision theoretic Bayes approach. Both cases, where the error variance is known or unknown, are included. Bayes decision rules are derived for noninformative and for normal priors. Bayes rules for noninformative priors are derived under a general loss function for designs that satisfy the BTIB condition of Bechhofer and Tamhane (Technometrics 23 (1981) 45). For unbalanced designs, a linear loss function is adopted and it is demonstrated, via simulations, that the simultaneous estimation of the selected treatment effect plays an important role in correcting an undesirable effect for the selection problem.
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- 2005
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41. Modulation of Airway Inflammation by Immunostimulatory CpG Oligodeoxynucleotides in a Murine Model of Allergic Aspergillosis
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J.D. Henderson, Jordan N. Fink, Naveen K. Bansal, Viswanath P. Kurup, Banani Banerjee, and Kevin J. Kelly
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Allergy ,Antigens, Fungal ,Immunology ,Down-Regulation ,Aspergillosis ,Immunoglobulin E ,Microbiology ,Basement Membrane ,Allergic inflammation ,Leukocyte Count ,Mice ,Eosinophilia ,medicine ,Animals ,Lung ,Interleukin 5 ,Antibodies, Fungal ,Glycoproteins ,Inflammation ,Mucous Membrane ,biology ,Aspergillus fumigatus ,Aspergillosis, Allergic Bronchopulmonary ,Allergens ,respiratory system ,Eosinophil ,medicine.disease ,Eosinophils ,Disease Models, Animal ,Infectious Diseases ,medicine.anatomical_structure ,Oligodeoxyribonucleotides ,biology.protein ,CpG Islands ,Parasitology ,Interleukin-4 ,Fungal and Parasitic Infections ,Interleukin-5 ,Antibody ,medicine.symptom ,Bronchoalveolar Lavage Fluid - Abstract
Allergic aspergillosis is a Th2 T-lymphocyte-mediated pulmonary complication in patients with atopic asthma and cystic fibrosis. Therefore, any therapeutic strategy that selectively inhibits Th2 T-cell activation may be useful in downregulating allergic lung inflammation in asthma. In the present study, we developed a CpG oligodeoxynucleotide (ODN)-based immune intervention of allergic inflammation in a mouse model of allergic aspergillosis. Four different groups of mice were used in a short-term immunization protocol. Three experimental groups of animals (groups 1 to 3) were sensitized withAspergillus fumigatusantigens. Animals in group 1 were immunized withA. fumigatusantigen alone, while those in group 2 were treated with CpG-ODN 1 day before the first antigen immunization, and the animals in group 3 received the first CpG-ODN administration between the antigen treatments. The animals in group 4 served as controls and were given phosphate-buffered saline. Allergen-specific serum immunoglobulins and total immunoglobulin E in different groups of animals were measured by enzyme-linked immunosorbent assay, while airway remodeling and cytokine production were studied by immunohistochemistry. The results demonstrated that CpG-ODN administration either before (group 2) or between (group 3) antigen treatments resulted in reduced total immunoglobulin E levels and peripheral blood eosinophil numbers compared toA. fumigatusallergen-sensitized group 1 animals. Similarly, treatment with CpG-ODN also downregulated inflammatory cell infiltration, goblet cell hyperplasia, and basement membrane thickening compared toA. fumigatus-sensitized mice. The distinct reduction in peripheral blood eosinophilia and airway remodeling in CpG-ODN-treated mice emphasized its usefulness as an immunomodulating agent for allergic fungal diseases.
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- 2004
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42. Addressing Health Disparities in Middle School Students' Nutrition and Exercise
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Mary Delgado, Mary Ho, Michael J. Havice, Heidi Schweizer, Yvonne Greer, Marilyn Frenn, Naveen K. Bansal, and Shelly Malin
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Male ,Gerontology ,Calorie ,Adolescent ,education ,Psychological intervention ,Health Promotion ,Social class ,03 medical and health sciences ,0302 clinical medicine ,Risk Factors ,Surveys and Questionnaires ,Intervention (counseling) ,Humans ,Medicine ,Nutritional Physiological Phenomena ,Obesity ,030212 general & internal medicine ,Child ,Exercise ,Community and Home Care ,Internet ,Schools ,030505 public health ,business.industry ,Public Health, Environmental and Occupational Health ,Feeding Behavior ,School health education ,medicine.disease ,Dietary Fats ,Health equity ,Health promotion ,Social Class ,Female ,Television ,0305 other medical science ,business ,Program Evaluation - Abstract
Those with low income, especially women of African American and Hispanic heritage have the greatest risk of inactivity and obesity. A 4-session (Internet and video) intervention with healthy snack and gym labs was tested in 2 (gym lab in 1) urban low-middle-income middle schools to improve low fat diet and moderate and vigorous physical activity.1 The gym lab was particularly beneficial (p = .002). Fat in diet decreased with each Internet session in which students participated. Percentage of fat in food was reduced significantly p = .018 for Black, White, and Black/Native American girls in the intervention group. Interventions delivered through Internet and video may enable reduction of health disparities in students by encouraging those most at risk to consume 30% or less calories from fat and to engage in moderate and vigorous physical activity.
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- 2003
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43. Aphasia type and aging in Hindi-speaking stroke patients
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Madakasira V. Padma, Manav K Bhatnagar, Apoorva Pauranik, M C Meheshwari, Meena Gupta, Deep C Jain, Naveen K. Bansal, Satish Jain, Subhash C. Bhatnagar, and Madhuri Bihari
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Adult ,Male ,Aging ,Linguistics and Language ,medicine.medical_specialty ,Cognitive Neuroscience ,media_common.quotation_subject ,Experimental and Cognitive Psychology ,Neurological disorder ,Audiology ,Severity of Illness Index ,behavioral disciplines and activities ,Language and Linguistics ,Literacy ,Developmental psychology ,Central nervous system disease ,Speech and Hearing ,Sex Factors ,Aphasia ,medicine ,Humans ,Language disorder ,Stroke ,Functional illiteracy ,Aged ,Language ,media_common ,Hindi ,Age Factors ,Middle Aged ,medicine.disease ,language.human_language ,nervous system diseases ,language ,Female ,medicine.symptom ,Psychology - Abstract
In this study, the clinical profile of Hindi-speaking stroke patients with aphasia from northern India has been investigated. We examined the interactional effect between age and gender with aphasia type in 97 Hindi-speaking right-handed individuals, the majority of them with a confirmed diagnosis of a cerebrovascular accident. The subjects included in the study ranged from 3 weeks to two years post-onset with a diagnosis of a common classical aphasia (Broca's, Wernicke's, anomic, global, conduction, and transcortical) types involving both males and females. Also examined was the interaction between literacy and aphasia type since the subjects had varied exposures to education (total illiteracy to professional/university education). While the data reported here about Hindi-speaking aphasics are relatively in agreement with the age-aphasia type patterns discussed in western countries, nonetheless some differences were also observed. The mean age of Indian patients with aphasia was significantly lower. Also, in addition to some gender and literacy related differences, an outstanding difference was that many clinical symptoms that are known to co-occur with aphasia were not readily reported by subjects with stroke.
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- 2002
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44. POISSON REGRESSION WITH A PERIODIC FUNCTION
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Naveen K. Bansal and Debasis Kundu
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Statistics and Probability ,Autocorrelation ,Estimator ,Asymptotic distribution ,Type (model theory) ,Poisson distribution ,Periodic function ,symbols.namesake ,Quasi-likelihood ,Consistent estimator ,Statistics ,symbols ,Applied mathematics ,Mathematics - Abstract
Let {yt } be a Poisson-like process with the mean μ t which is a periodic function of time t. We discuss how to fit this type of data set using quasi-likelihood method. Our method provides a new avenue to fit a time series data when the usual assumption of stationarity and homogeneous residual variances are invalid. We show that the estimators obtained are strongly consistent and also asymptotically normal.
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- 2002
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45. Simultaneous selection and estimation in general linear models
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Naveen K. Bansal and Klaus J. Miescke
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Statistics and Probability ,Bayes' rule ,General linear model ,Mathematical optimization ,Bayes estimator ,Applied Mathematics ,Linear model ,Bayes' theorem ,Prior probability ,Statistics ,Statistics::Methodology ,Bayes error rate ,Nuisance parameter ,Statistics, Probability and Uncertainty ,ComputingMilieux_MISCELLANEOUS ,Mathematics - Abstract
The problem of selecting the largest treatment parameter, and simultaneously estimating the selected treatment parameter, in a general linear model is considered in the decision theoretic Bayes approach. Both cases, where the error variance is known or unknown, are included. Bayes decision rules are derived for noninformative priors and for normal priors. The problem of finding Bayes designs, i.e. designs that have minimum Bayes risk, within a given class of designs is also discussed.
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- 2002
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46. Testing multiple hypotheses with skewed alternatives
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Naveen K, Bansal, Gholamhossein G, Hamedani, and Mehdi, Maadooliat
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Models, Statistical ,Gene Expression Profiling ,Computational Biology ,Humans ,Bayes Theorem ,Computer Simulation ,HIV Infections ,Artifacts ,Monte Carlo Method ,Oligonucleotide Array Sequence Analysis - Abstract
In many practical cases of multiple hypothesis problems, it can be expected that the alternatives are not symmetrically distributed. If it is known a priori that the distributions of the alternatives are skewed, we show that this information yields high power procedures as compared to the procedures based on symmetric alternatives when testing multiple hypotheses. We propose a Bayesian decision theoretic rule for multiple directional hypothesis testing, when the alternatives are distributed as skewed, under a constraint on a mixed directional false discovery rate. We compare the proposed rule with a frequentist's rule of Benjamini and Yekutieli (2005) using simulations. We apply our method to a well-studied HIV dataset.
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- 2014
47. A Bayesian methodology for detecting targeted genes under two related experiments
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Naveen K, Bansal, Hongmei, Jiang, and Prachi, Pradeep
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MicroRNAs ,Models, Statistical ,Gene Expression Regulation ,Gene Expression Profiling ,Databases, Genetic ,Down-Regulation ,Humans ,Bayes Theorem ,Computer Simulation ,Algorithms ,Up-Regulation - Abstract
Many gene expression data are based on two experiments where the gene expressions of the targeted genes under both experiments are correlated. We consider problems in which objectives are to find genes that are simultaneously upregulated/downregulated under both experiments. A Bayesian methodology is proposed based on directional multiple hypotheses testing. We propose a false discovery rate specific to the problem under consideration, and construct a Bayes rule satisfying a false discovery rate criterion. The proposed method is compared with a traditional rule through simulation studies. We apply our methodology to two real examples involving microRNAs; where in one example the targeted genes are simultaneously downregulated under both experiments, and in the other the targeted genes are downregulated in one experiment and upregulated in the other experiment. We also discuss how the proposed methodology can be extended to more than two experiments.
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- 2014
48. A note on random fields forming conditional bases
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Gholamhossein G. Hamedani, Hao Zhang, and Naveen K. Bansal
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Statistics and Probability ,Conditional entropy ,Random field ,Stochastic process ,Hilbert space ,Conditional probability distribution ,symbols.namesake ,Calculus ,symbols ,Statistical physics ,Statistics, Probability and Uncertainty ,Variogram ,Spatial analysis ,Mathematics - Abstract
We study properties of random fields that form conditional bases and their applications in spatial statistics.
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- 2000
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49. Detection of immunoglobulin antibodies in the sera of patients using purified latex allergens
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Williams B, Hoong Yeet Yeang, Viswanath P. Kurup, Sussman Gl, Naveen K. Bansal, Jordan N. Fink, Kevin J. Kelly, Donald R. Hoffman, and Donald H. Beezhold
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Allergy ,Latex Hypersensitivity ,medicine.diagnostic_test ,biology ,Spina bifida ,business.industry ,Radioallergosorbent test ,Immunology ,medicine.disease ,medicine.disease_cause ,Immunoglobulin E ,Allergen ,Latex allergy ,medicine ,biology.protein ,Immunology and Allergy ,Antibody ,business - Abstract
Background Latex allergy is largely an occupational allergy due to sensitization to natural rubber latex allergens present in a number of health care and household products. Although several purified allergens are currently available for study, information on the usefulness of these purified, native or recombinant allergens in the demonstration of specific immunoglobulin (Ig) E in the sera of patients is lacking. Objective To evaluate the purified latex allergens and to demonstrate specific IgE antibody in the sera of health care workers and spina bifida patients with clinical latex allergy. Methods Two radioallergosorbent and an enzyme-linked immunosorbent assay (ELISA) using latex proteins Hev b 1, 2, 3, 4, 6 and 7 along with two glove extracts and Malaysian nonammoniated latex (MNA) were evaluated to demonstrate IgE in the sera of health care workers and spina bifida with latex allergy and controls with no history of latex allergy. Results ELISA using the purified latex allergens demonstrated specific IgE in 32–65% health care workers and 54–100% of spina bifida patients with latex allergy. The corresponding figures for RAST were 13–48 and 23–85 for RAST-1 and 19–61 and 36–57 for RAST-2. These results were comparable with the results obtained with glove extracts and crude rubber latex proteins. Conclusions When used simultaneously, latex proteins Hev b 2 and Hev b 7 reacted significantly with specific serum IgE in 80% of health care workers and 92% of spina bifida patients with latex allergy by ELISA technique, while this combination gave lower positivity when the RASTs were used. By the addition of Hev b 3, specific IgE was detected in all spina bifida patients with latex allergy. Both RASTs failed to show specific IgE in the control subjects, while the ELISA showed significant latex-specific IgE in 22% of controls.
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- 2000
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50. Non-linear regression with multidimensional indices
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Naveen K. Bansal, Hao Zhang, and Gholamhossein G. Hamedani
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Statistics and Probability ,Harmonic function ,Consistent estimator ,Mathematical analysis ,Asymptotic distribution ,Estimator ,Applied mathematics ,Regression analysis ,Statistics, Probability and Uncertainty ,Type (model theory) ,Asymptotic theory (statistics) ,Nonlinear regression ,Mathematics - Abstract
We consider a non-linear regression model when the index variable is multidimensional. Sucient conditions on the non-linear function are given under which the least-squares estimators are strongly consistent and asymptotically normally distributed. These sucient conditions are satised by harmonic type functions, which are also of interest in the one dimensional index case where Wu’s (Asymptotic theory of non-linear least-squares estimation, Ann. Statist. 9 (1981) 501{513) and Jennrich’s (Asymptotic properties of non-linear least-squares estimators, Ann. Math. Statist. 40 (1969) 633{643) sucient conditions are not applicable. c 1999 Elsevier Science B.V. All rights reserved
- Published
- 1999
- Full Text
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