480 research outputs found
E-ABR in patients with cochlear implant: A comparison between patients with malformed cochlea and normal cochlea
OBJECTIVES: This study aims to compare the electrical auditory brainstem response (EABR) following cochlear implant (CI) surgery in pediatric subjects with cochlear malformation and a normal cochlea, in order to assess the sensitivity of EABR and to evaluate the surgery outcome. MATERIALS and METHODS: A total of 26 pediatric subjects who were deaf and scheduled for CI surgery were enrolled into this case control study. Group A (n=20) included subjects with a normo-conformed cochlea. Group B (n=6) included subjects with cochlear malformation. Subjects were evaluated with EABR immediately (T0) and 6 months (T1) post-CI surgery. The EABR Waves III and V average amplitude and latency were compared across time, separately for each group, and across groups, separately for each time. RESULTS: Auditory brainstem response (ABR) could only be recorded in Group A. We were able to record EABR from all subjects at T0 and T1, and waves III and V were present in all the recorded signals. There were no statistically significant differences between T0 and T1 in EABR Waves III and V in terms of average amplitude and latency in neither group. When comparing Groups A and B, the only statistically significant difference was the average amplitude of wave V, both at T0 and T1. CONCLUSION: EABR is a valid tool to measure the auditory nerve integrity after CI surgery in patients with a normal and malformed cochlea, as shown by its ability to measure waves III and V when ABR is absent. The EABR testing should be performed before and after CI surgery, and EABR should be used as a measure of outcome, especially in patients with a malformed cochlea
Using Biologic Markers in Blood to Assess Exposure to Multiple Environmental Chemicals for Inner-City Children 3–6 Years of Age
We assessed concurrent exposure to a mixture of > 50 environmental chemicals by measuring the chemicals or their metabolites in the blood of 43 ethnically diverse children (3–6 years of age) from a socioeconomically disadvantaged neighborhood in Minneapolis. Over a 2-year period, additional samples were collected every 6–12 months from as many children as possible. We analyzed blood samples for 11 volatile organic compounds (VOCs), 2 heavy metals (lead and mercury, 11 organochlorine (OC) pesticides or related compounds, and 30 polychlorinated biphenyl (PCB) congeners. The evidence suggests that numerous VOCs originated from common sources, as did many PCBs. Longitudinal measurements indicate that between-child variance was greater than within-child variance for two VOCs (benzene, toluene), for both heavy metals (Pb, Hg), for all detectable OC pesticides, and for 15 of the measured PCB congeners (74, 99, 101, 118, 138–158, 146, 153, 156, 170, 178, 180, 187, 189, 194, 195). Despite the relatively small sample size, highest measured blood levels of 1,4-dichlorobenzene, styrene, m-/p-xylene, Pb, Hg, heptachlor epoxide, oxychlordane, dichlorodiphenyldichloroethene (p,p′-DDE), trans-nonachlor, and PCB congeners 74, 99, 105, 118, 138, 146, 153, 156, 170, and 180 were comparable with or higher than 95th percentile measurements of older children and adults from national surveys. Results demonstrate that cumulative exposures to multiple environmental carcinogens and neurotoxins can be comparatively high for children from a poor inner-city neighborhood
Deep Reinforcement Learning for Surgical Gesture Segmentation and Classification
Recognition of surgical gesture is crucial for surgical skill assessment and
efficient surgery training. Prior works on this task are based on either
variant graphical models such as HMMs and CRFs, or deep learning models such as
Recurrent Neural Networks and Temporal Convolutional Networks. Most of the
current approaches usually suffer from over-segmentation and therefore low
segment-level edit scores. In contrast, we present an essentially different
methodology by modeling the task as a sequential decision-making process. An
intelligent agent is trained using reinforcement learning with hierarchical
features from a deep model. Temporal consistency is integrated into our action
design and reward mechanism to reduce over-segmentation errors. Experiments on
JIGSAWS dataset demonstrate that the proposed method performs better than
state-of-the-art methods in terms of the edit score and on par in frame-wise
accuracy. Our code will be released later.Comment: 8 pages, 2 figures, accepted for MICCAI 201
Determining Magnetic Nanoparticle Size Distributions from Thermomagnetic Measurements
Thermomagnetic measurements are used to obtain the size distribution and
anisotropy of magnetic nanoparticles. An analytical transformation method is
described which utilizes temperature-dependent zero-field cooling (ZFC)
magnetization data to provide a quantitative measurement of the average
diameter and relative abundance of superparamagnetic nanoparticles. Applying
this method to self-assembled MnAs nanoparticles in MnAs-GaAs composite films
reveals a log-normal size distribution and reduced anisotropy for nanoparticles
compared to bulk materials. This analytical technique holds promise for rapid
assessment of the size distribution of an ensemble of superparamagnetic
nanoparticles.Comment: Correction Appl. Phys. Lett. 98, 216103 (2011
MIBG detection of hepatic neuroblastoma: Correlation with CT, US and surgical findings
Metaiodobenzylguanidine (MIBG) imaging is used in the diagnosis, staging and follow-up of virtually every case of neuroblastoma seen at our institution. Normal sites of MIBG uptake include the liver and therefore difficulties have been predicted and encountered in the diagnosis of hepatic neuroblastoma due to inability to separate abnormally increased tracer deposition from normal hepatic activity. We reviewed every MIBG (I 123 and I 131 ) study performed at our pediatric hospital over a 4 year period encompassing 88 patients, 67 of whom had biopsy proven neuroblastoma. Hepatic findings on MIBG studies were compared with concurrent abdominal CT and US studies in all 67 patients. The clinical records of all patients with abnormal MIBG scans or abnormal CT or US studies of the liver were also reviewed. Eight patients were found to have abnormal liver findings on one or more imaging studies (MIBG, CT, or US). There were 3 true positive MIBG studies, one of which was an early study in a patient who later went on to have one of the false positive studies. Two patients had false positive MIBG scans for liver neuroblastoma. MIBG failed to detect liver involvement in 4 patients.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/46701/1/247_2005_Article_BF02010914.pd
Relationship between psychological and biological factors and physical activity and exercise behaviour in Filipino students
The aim of the present study was threefold. Firstly, it investigated whether a general measure or specific measure of motivational orientation was better in describing the relationship between motivation and exercise behaviour. Secondly, it examined the relationship between the four most popular indirect methods of body composition assessment and physical activity and exercise patterns. Thirdly, the interaction between motivation and body composition on physical activity and exercise behaviour was explored in a sample of 275 Filipino male and female students. Males were found to have higher levels of exercise whereas females had higher levels of physical activity. Furthermore, general self-motivation together with body weight and percentage body fat were found to be the best predictor of exercise behaviour whereas the tension/pressure subscale of the ‘Intrinsic Motivation Inventory’ (IMI) was the best predictor of levels of physical activity. However, significant gender differences were observed. That is, for the males only self-motivation and for the females only body weight and BMI predicted exercise behaviour. Also, tension/pressure predicted physical activity levels for the females but not the males. No inverse relationship was found between the four body composition measures and exercise and physical activity behaviour. The results support the notion that the psychobiological approach might be particularly relevant for high intensity exercise situations but also highlights some important gender differences. Finally, the results of this study emphasise the need for more cross-cultural research
Calcium-fortified beverage supplementation on body composition in postmenopausal women
BACKGROUND: We investigated the effects of a calcium-fortified beverage supplemented over 12 months on body composition in postmenopausal women (n = 37, age = 48–75 y). METHODS: Body composition (total-body percent fat, %Fat(TB); abdominal percent fat, %Fat(AB)) was measured with dual energy x-ray absorptiometry. After baseline assessments, subjects were randomly assigned to a free-living control group (CTL) or the supplement group (1,125 mg Ca(++)/d, CAL). Dietary intake was assessed with 3-day diet records taken at baseline and 12 months (POST). Physical activity was measured using the Yale Physical Activity Survey. RESULTS: At 12 months, the dietary calcium to protein ratio in the CAL group (32.3 ± 15.6 mg/g) was greater than the CTL group (15.2 ± 7.5 mg/g). There were no differences from baseline to POST between groups for changes in body weight (CAL = 0.1 ± 3.0 kg; CTL = 0.0 ± 2.9 kg), %Fat(TB )(CAL = 0.0 ± 2.4%; CTL = 0.5 ± 5.4%), %Fat(AB )(CAL = -0.4 ± 8.7%; CTL = 0.6 ± 8.7%), or fat mass (CAL = 1.3 ± 2.6 kg; CTL = 1.3 ± 2.7 kg). CONCLUSION: These results indicate that increasing the calcium to protein ratio over two-fold by consuming a calcium-fortified beverage for 12 months did not decrease body weight, body fat, or abdominal fat composition in postmenopausal women
A working model of stroke recovery from rehabilitation robotics practitioners
We reviewed some of our initial insights about the process of upper-limb behavioral recovery following stroke. Evidence to date indicates that intensity, task specificity, active engagement, and focusing training on motor coordination are key factors enabling efficacious recovery. On modeling, experience with over 400 stroke patients has suggested a working model of recovery similar to implicit motor learning. Ultimately, we plan to apply these insights in the development of customized training paradigms to enhance recovery
Intravesical oxybutinin chloride in children with intermittent catheterization: Sonographic findings
The sonographic findings in the bladder are presented in four children with myelomeningocele and neurogenic dysfunction of the bladder, who were treated with intermittent self-catheterization and intravesical oxybutinin chloride. All were referred for routine sonography of the urinary tract. Each had infused a crushed tablet of oxybutinin chloride intravesically 30–120 min before the examination. In two children, brightly echogenic, non-shadowing particles were suspended in the bladder urine. In one of these, the particles swirled giving the impression of a “snowstorm”; in the other, most of the particles gradually settled forming an irregular clump on the bladder base. In the remaining two children, the urine appeared diffusely hazy with innumerable tiny particles giving the impression of a fine mist filling the bladder. The sonographic appearance of the urine in the bladder after intravesical instillation of crushed tablets can be dramatic and can simulate pus, blood, fungus, or other debris in the bladder lumen. In the absence of clinical symptoms or hematuria, a history of recent infusion of medication into the bladder should be sought.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/46706/1/247_2005_Article_BF02012126.pd
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