Open Access. Powered by Scholars. Published by Universities.®

Medicine and Health Sciences Commons™

Open Access. Powered by Scholars. Published by Universities.®

Analytical, Diagnostic and Therapeutic Techniques and Equipment

2013

University of Nebraska - Lincoln

Articles 1 - 11 of 11

Full-Text Articles in Medicine and Health Sciences

Sex Differences In White Matter Development During Adolescence: A Dti Study, Yingying Wang, Chris Adamson, Weihong Yuan, Mekibib Altaye, Anna W. Byars, Scott K. Holland Oct 2013

Sex Differences In White Matter Development During Adolescence: A Dti Study, Yingying Wang, Chris Adamson, Weihong Yuan, Mekibib Altaye, Anna W. Byars, Scott K. Holland

Center for Brain, Biology, and Behavior: Faculty and Staff Publications

Adolescence is a complex transitional period in human development, composing physical maturation, cognitive and social behavioral changes. The objective of this study is to investigate sex differences in white matter development and the associations between intelligence and white matter microstructure in the adolescent brain using diffusion tensor imaging (DTI) and tract-based spatial statistics (TBSS). In a cohort of 16 typically-developing adolescents aged 13 to 17 years, longitudinal DTI data were recorded from each subject at two time points that were one year apart. We used TBSS to analyze the diffusion indices including fractional anisotropy (FA), mean diffusivity (MD), axial diffusivity …

Go to article

Combined Erp/Fmri Evidence For Early Word Recognition Effects In The Posterior Inferior Temporal Gyrus, Joseph Dien, Eric S. Brian, Dennis L. Molfese, Brian T. Gold Oct 2013

Combined Erp/Fmri Evidence For Early Word Recognition Effects In The Posterior Inferior Temporal Gyrus, Joseph Dien, Eric S. Brian, Dennis L. Molfese, Brian T. Gold

Center for Brain, Biology, and Behavior: Faculty and Staff Publications

Two brain regions with established roles in reading are the posterior middle temporal gyrus and the posterior fusiform gyrus. Lesion studies have also suggested that the region located between them, the posterior inferior temporal gyrus (pITG), plays a central role in word recognition. However, these lesion results could reflect disconnection effects since neuroimaging studies have not reported consistent lexicality effects in pITG. Here we tested whether these reported pITG lesion effects are due to disconnection effects or not using parallel ERP/fMRI studies. We predicted that the Recognition Potential (RP), a left-lateralized ERP negativity that peaks at about 200–250 ms, might …

Go to article

Measurement And Description Of Dynamics Required For In Vivo Surgical Robotics Via Kinematic Methods, Jacob G. Greenburg Aug 2013

Measurement And Description Of Dynamics Required For In Vivo Surgical Robotics Via Kinematic Methods, Jacob G. Greenburg

Department of Mechanical and Materials Engineering: Dissertations, Theses, and Student Research

With the goal of improved recovery times and reduced trauma to the patient there has been a substantial shift in the medical community’s demand for minimally invasive surgical (MIS) techniques. With the standardization of MIS becoming more commonplace in the medical field there are still many improvements that are desired. Traditional, manual methods of these surgeries require multiple incisions on the abdomen for the tools and instruments to be inserted. The more recent demand has been to localize the incisions into what is being referred to as a Laparoendoscopic Single-Site (LESS) surgery. Furthermore, the manual instruments that are commonly used …

Go to article

Experimental Assessment Of The Impact Of Asymptomatic Gas Emboli On The Vessel Wall, Linxia Gu, Eric L. Cutler Jun 2013

Experimental Assessment Of The Impact Of Asymptomatic Gas Emboli On The Vessel Wall, Linxia Gu, Eric L. Cutler

Department of Mechanical and Materials Engineering: Faculty Publications

Quantitative evaluation of shear stress in the vessel wall due to the presence of asymptomatic gas emboli is lacking. The goal of this work was to assess the impact of chronic asymptomatic gas emboli on the risk of atherosclerosis through a custom-built cardiovascular flow simulator. Gas bubbles were created by forced air from a syringe pump. The influences of embolism injection rate, pulse rate, and time-averaged flow rate on the wall mean shear stress were investigated at resting and elevated heart rate conditions. The recorded pressure and volumetric flow rate from 24 experimental settings with four repetitions each were used …

Go to article

Concordance Of Meg And Fmri Patterns In Adolescents During Verb Generation, Yingying Wang, Scott K. Holland, Jennifer Vannest Apr 2013

Concordance Of Meg And Fmri Patterns In Adolescents During Verb Generation, Yingying Wang, Scott K. Holland, Jennifer Vannest

Center for Brain, Biology, and Behavior: Faculty and Staff Publications

In this study we focused on direct comparison between the spatial distributions of activation detected by functional magnetic resonance imaging (fMRI) and localization of sources detected by magnetoencephalography (MEG) during identical language tasks. We examined the spatial concordance between MEG and fMRI results in 16 adolescents performing a three-phase verb generation task that involves repeating the auditorily presented concrete noun and generating verbs either overtly or covertly in response to the auditorily presented noun. MEG analysis was completed using a synthetic aperture magnetometry (SAM) technique, while the fMRI data were analyzed using the general linear model approach with random-effects. To …

Go to article

Data Mining The Functional Characterizations Of Proteins To Predict Their Cancer-Relatedness, Peter Revesz, Christopher Assi Feb 2013

Data Mining The Functional Characterizations Of Proteins To Predict Their Cancer-Relatedness, Peter Revesz, Christopher Assi

School of Computing: Faculty Publications

This paper considers two types of protein data. First, data about protein function described in a number of ways, such as, GO terms and PFAM families. Second, data about whether individual proteins are experimentally associated with cancer by an anomalous elevation or lowering of their expressions within cancerous cells. We combine these two types of protein data and test whether the first type of data, that is, the functional descriptors, can predict the second type of data, that is, cancer-relatedness. By using data mining and machine learning, we derive a classifier algorithm that using only GO term and PFAM family …

Go to article

Micromechanical Analysis Of Nanoparticle-Reinforced Dental Composites, Yi Hua, Linxia Gu, Hidehiko Watanabe Jan 2013

Micromechanical Analysis Of Nanoparticle-Reinforced Dental Composites, Yi Hua, Linxia Gu, Hidehiko Watanabe

Department of Mechanical and Materials Engineering: Faculty Publications

The mechanical behavior of TiO2 nanoparticle-reinforced resin-based dental composites was characterized in this work using a three-dimensional nanoscale representative volume element. The impacts of nanoparticle volume fraction, aspect ratio, stiffness, and interphase zone between the resin matrix and nanoparticle on the bulk properties of the composite were characterized. Results clearly demonstrated the mechanical advantage of nanocomposites in comparison to microfiber-reinforced composites. The bulk response of the nanocomposite could be further enhanced with the increased nanoparticle volume fraction, or aspect ratio, while the influence of nanoparticle stiffness was minimal. The effective Young’s modulus and yield strength of the composite was …

Go to article

A One-Hour Sleep Restriction Impacts Brain Processing In Young Children Across Tasks: Evidence From Event-Related Potentials, Dennis Molfese, Anna Ivanenko, Alexandra P.F. Key, Adrienne Roman, Victoria J. Molfese, Louise M. O'Brien, David Gozal, Srinivas Kota, Caitlin M. Hudac Jan 2013

A One-Hour Sleep Restriction Impacts Brain Processing In Young Children Across Tasks: Evidence From Event-Related Potentials, Dennis Molfese, Anna Ivanenko, Alexandra P.F. Key, Adrienne Roman, Victoria J. Molfese, Louise M. O'Brien, David Gozal, Srinivas Kota, Caitlin M. Hudac

Center for Brain, Biology, and Behavior: Faculty and Staff Publications

The effect of mild sleep restriction on cognitive functioning in young children is unclear, yet sleep loss may impact children's abilities to attend to tasks with high processing demands. In a preliminary investigation, six children (6.6 - 8.3 years of age) with normal sleep patterns performed three tasks: attention (“Oddball”), speech perception (conconant-vowel syllables) and executive function (Directional Stroop). Event-related potentials (ERP) responses were recorded before (Control) and following one-week of 1-hour per day of sleep restriction. Brain activity across all tasks following Sleep Restriction differed from activity during Control Sleep, indicating that minor sleep restriction impacts children's neurocognitive functioning.

Go to article

Normative Topographic Erp Analyses Of Speed Of Speech Processing And Grammar Before And After Grammatical Treatment, Paul J. Yoder, Dennis Molfese, Micah M. Murray, Alexandra P.F. Key Jan 2013

Normative Topographic Erp Analyses Of Speed Of Speech Processing And Grammar Before And After Grammatical Treatment, Paul J. Yoder, Dennis Molfese, Micah M. Murray, Alexandra P.F. Key

Center for Brain, Biology, and Behavior: Faculty and Staff Publications

Typically developing (TD) preschoolers and age-matched preschoolers with specific language impairment (SLI) received event-related potentials (ERPs) to four monosyllabic speech sounds prior to treatment and, in the SLI group, after 6 months of grammatical treatment. Before treatment, the TD group processed speech sounds faster than the SLI group. The SLI group increased the speed of their speech processing after treatment. Post-treatment speed of speech processing predicted later impairment in comprehending phrase elaboration in the SLI group. During the treatment phase, change in speed of speech processing predicted growth rate of grammar in the SLI group.

Go to article

Personalizing Aac For People With Aphasia: The Role Of Text And Pictures, Aimee R. Dietz, Kristy S.E. Weissling, Julie Griffith, Miechelle L. Mckelvey Jan 2013

Personalizing Aac For People With Aphasia: The Role Of Text And Pictures, Aimee R. Dietz, Kristy S.E. Weissling, Julie Griffith, Miechelle L. Mckelvey

Department of Special Education and Communication Disorders: Faculty Publications

Over time, and with intensive instruction, people with aphasia (PWAs) can learn to use grid-based, categorically organized, high-technology AAC layouts during structured tasks (e.g., Hough & Johnson, 2009). In an effort to reduce the training intensity required to teach PWAs to use AAC; researchers developed visual scene displays (VSDs), designed to complement the residual cognitive and linguistic abilities of PWAs by tapping their intact episodic memory. VSD interfaces incorporate personally relevant (PR) photos, text, and speech output (Dietz, McKelvey, & Beukelman, 2006; Weissling & Beukelman, 2006). VSDs appear to facilitate improved communication success (e.g., McKelvey, Dietz, Hux, Weissling, & Beukelman, …

Go to article

Supporting Narrative Retells For People With Aphasia Using Aac: Photographs Or Line Drawings? Text Or No Text?, Julie Griffith, Aimee R. Dietz, Kristy S.E. Weissling Jan 2013

Supporting Narrative Retells For People With Aphasia Using Aac: Photographs Or Line Drawings? Text Or No Text?, Julie Griffith, Aimee R. Dietz, Kristy S.E. Weissling

Department of Special Education and Communication Disorders: Faculty Publications

People with aphasia (PWAs) have demonstrated the ability to learn augmentative and alternative communication (AAC) devices that employ traditional grid layouts to enhance their communication; however, the process is typically lengthy and yields limited generalization (Fox & Fried-Oken, 2001; Koul & Harding, 1998). In response, researchers have begun to investigate the use of visual scene displays (VSDs) to support the communication interactions of PWAs by capitalizing on their relatively intact episodic memory (Beukelman, Dietz, McKelvey, Hux, & Weissling, in press; Dietz, Beukelman, & McKelvey, 2006a; Dietz, McKelvey, Beukelman, Weissling, & Hux, 2006b; McKelvey, Dietz, Hux, Weissling, & Beukelman, 2007). High-technology …

Go to article