Girls Speak: A New Voice in Global Development

Presents adolescent girls' views on the value of education and its impact on their lives, their aspirations, and barriers to long-term change as guidance for targeting interventions to improve self-determination and health, social, and economic outcomes

Robotic task-specific training of the upper extremity in children with Cerebral Palsy

poster abstractBackground: Cerebral Palsy (CP) affects at least 2 in 1,000 children in the United States. The disorder is non-progressive, yet secondary impairments can worsen over time leading to contracture, decreased strength, increased tone and ultimately, impaired mobility and function. Robotic therapy has been found to have positive outcomes for similar impairments in stroke neuro-recovery, suggesting the need for the application of this technology to CP. Purpose: The purpose of this study was to investigate whether specific upper extremity (UE) robotic training improves UE function in children with CP. Methods: This is an ongoing study currently with 5 children (ages 4-12) with CP that have completed the treatment intervention. Inclusion criteria included a hemiplegic presentation of the UE, a modified Ashworth scale (MAS) score of 2 or less and wrist extension equal to or greater than 0o in the affected arm, and sufficient cognition to attain to a task for 40-60 minutes. Each child participated in 16 total robotic training sessions occurring twice weekly, with each session consisting of 1,040 task-specific reaching movements of the affected arm with real-time impedance control. Pre- and post-testing and a 1-month follow-up were performed for each subject. Clinical outcome measures included active range of motion (AROM), passive range of motion (PROM), manual muscle tests (MMT), and grip strength, in addition to functional tests including the MAS, adaptive Fugl-Meyer scale, and the Pediatric Evaluation of Disability Inventory (PEDI) assessed by parents. Lastly, spatial-temporal control patterns were collected during each session, allowing for a visual assessment of a child’s progress in refining UE movement patterns to 16 positions across all quadrants. Results: For AROM and PROM, 4 of 5 subjects demonstrated an increase in at least 2 joints by 1-month follow-up. The remaining measurements produced no change or change within the standard error for goniometry (+/- 5o), while no decline was noted in any subjects. Pre-test MMT revealed strength measures ranging from 3/5 to 5/5. By 1-month follow-up, 85% of all measurements were 5/5, with the remaining 15% at 4+/5. For grip strength, 3 of 4 subjects (fifth subject unavailable) doubled their strength by 1-month follow-up, with the last demonstrating symmetry with the unaffected limb. Tone, as measured by MAS, did not appear to be a limiting factor as only 1 child displayed any noticeable tone (MAS of 2) across the measured motions. For the Fugl-Meyer, 4 of 5 subjects improved coordination by more than 2 points by 1- month follow-up, while the fifth maintained throughout the study. Parents reported via the PEDI an overall improvement in performing functional tasks for all children during the study, with 4 of 5 subjects improving by 10 or more points. Lastly, spatial-temporal control patterns showed marked improvement for all subjects by 1-month follow-up. Conclusion: Early results indicate that the application of robotic training to children with CP improved several clinical measures of the affected limb. This likely resulted in increased use of the affected limb, leading to improved functional performance

LP-based Covering Games with Low Price of Anarchy

We present a new class of vertex cover and set cover games. The price of anarchy bounds match the best known constant factor approximation guarantees for the centralized optimization problems for linear and also for submodular costs -- in contrast to all previously studied covering games, where the price of anarchy cannot be bounded by a constant (e.g. [6, 7, 11, 5, 2]). In particular, we describe a vertex cover game with a price of anarchy of 2. The rules of the games capture the structure of the linear programming relaxations of the underlying optimization problems, and our bounds are established by analyzing these relaxations. Furthermore, for linear costs we exhibit linear time best response dynamics that converge to these almost optimal Nash equilibria. These dynamics mimic the classical greedy approximation algorithm of Bar-Yehuda and Even [3]

Differences in Demographic, Behavioral, and Biological Variables Between Those With Valid and Invalid Accelerometry Data: Implications for Generalizability

Background: The exclusion of participants with invalid accelerometry data (IAD) may lead to biased results and/or lack of generalizability in large population studies. The purpose of this study was to investigate whether demographic, behavioral, and biological differences occur between those with IAD and valid accelerometry data (VAD) among adults using a representative sample of the civilian noninstitutionalized U.S. population. Methods: Ambulatory participants from NHANES (2003-2004) who were 20-85 years of age were included in the current study and wore an ActiGraph 7164 accelerometer for 7 days. A valid person was defined as those with 4 or more days of at least 10+ hrs of monitoring per day. Among adults (20-85 yrs), 3088 participants provided VAD and 987 provided IAD. Demographic, behavioral, and biological information were obtained from the household interview or from data obtained in a mobile examination center. Results: Differences were observed in age, BMI, ethnicity, education, smoking status, marital status, use of street drugs, current health status, HDL-cholesterol, C-reactive protein, self-reported vigorous physical activity, and plasma glucose levels between those with VAD and IAD. Conclusions: Investigators should take into consideration the potential cut-off bias in interpreting results based on data that excludes IAD participants

The Impact of Variable Dosage Using Robotic-assisted Task-Specific Upper Extremity Training in Children with Cerebral Palsy

poster abstractBackground: Cerebral Palsy (CP) and other acquired neurological disorders result from brain lesions that alter motor function in children. The impact of these deficits can impair a child’s ability to use their upper extremity (UE) for normal daily activities such as eating and playing. Robotic-assisted therapy has been shown to improve motor function in children with CP. Training parameters such as intensity and frequency were initially based on findings from studies measuring change in adults following stroke. Based on this, high intensity (960 repetitions per session) and increased frequency (2 times per week, 9 weeks) were initially implemented for children. Early findings demonstrated improvement in UE function for children with CP; however, training sessions were long, making them difficult to complete given the shorter attention span of the pediatric population. Determining the potential impact of a shorter, more optimal, dosage of robotic-assisted therapy for children would facilitate rehab training efficiency and maximize cost effectiveness. Purpose: The purpose of this study was to identify the impact on motor impairments and movement capacity with variances in treatment intensity (number of repetitions per session) while holding constant the frequency of the application (2 times per week, 9 weeks) for robotic-assisted UE training for children with CP. Methods: Six children between the ages of 6 and 8 were analyzed from two separate studies evaluating the effectiveness of robotic-assisted training for UE functional improvement. The first study featured training at high intensity and frequency while the second study used lower intensity parameters but the same frequency. To be eligible for either study, children were required to have UE hemiplegia and the ability to participate in a task for up to 60 minutes. Twice weekly, each child participated in robotic training sessions consisting of either 960, 640, or 320 task-specific reaching movements of the affected UE. Each child completed a total of 16 robotic training sessions over a 9-week period as well as one pre- and one post-test session. Outcome measures included active range of motion (AROM), strength testing and tone using the Modified Ashworth Scale (MAS). The children’s motor capacity was evaluated using the adaptive Fugl-Meyer scale (FM). Results: Percent change scores were calculated for each participant for each outcome measurement. AROM results for the shoulder resulted in an average increase of 10.6% for flexion and a 13.3% increase for abduction in both the 320 and 640 groups. Shoulder external rotation increased by an average of 13.6% for all three groups. Arm strength increased an average of 12.3% for all three groups. The MAS had an average decrease in tone of 23.8% across all 3 groups. Scores on the FM increased an average of 23% with in-depth analysis revealing shoulder movement to be the primary area for motor capacity change at 96%. Conclusion: These findings indicate that lower intensities of robotic-assisted therapy (320 and 640 repetitions) were as effective as the larger dose originally prescribed for children with CP. Outcome measures improved in all 3 groups and did not vary between dosing groups. This suggests that longer intensity sessions of robotic-assisted therapies may not be necessary to produce AROM, strength, and motor capacity changes. Further trials with more subjects are needed to validate these results

The Impact of Problem-Based Learning on Problem-Solving Skills

My starred paper examines the effect problem based learning has on the problem solving skills of students who participate in classes using the problem based learning method

Kitaev's quantum double model from a local quantum physics point of view

A prominent example of a topologically ordered system is Kitaev's quantum double model $\mathcal{D}(G)$ for finite groups $G$ (which in particular includes $G = \mathbb{Z}_2$, the toric code). We will look at these models from the point of view of local quantum physics. In particular, we will review how in the abelian case, one can do a Doplicher-Haag-Roberts analysis to study the different superselection sectors of the model. In this way one finds that the charges are in one-to-one correspondence with the representations of $\mathcal{D}(G)$, and that they are in fact anyons. Interchanging two of such anyons gives a non-trivial phase, not just a possible sign change. The case of non-abelian groups $G$ is more complicated. We outline how one could use amplimorphisms, that is, morphisms $A \to M_n(A)$ to study the superselection structure in that case. Finally, we give a brief overview of applications of topologically ordered systems to the field of quantum computation.Comment: Chapter contributed to R. Brunetti, C. Dappiaggi, K. Fredenhagen, J. Yngvason (eds), Advances in Algebraic Quantum Field Theory (Springer 2015). Mainly revie

Rank-based model selection for multiple ions quantum tomography

The statistical analysis of measurement data has become a key component of many quantum engineering experiments. As standard full state tomography becomes unfeasible for large dimensional quantum systems, one needs to exploit prior information and the "sparsity" properties of the experimental state in order to reduce the dimensionality of the estimation problem. In this paper we propose model selection as a general principle for finding the simplest, or most parsimonious explanation of the data, by fitting different models and choosing the estimator with the best trade-off between likelihood fit and model complexity. We apply two well established model selection methods -- the Akaike information criterion (AIC) and the Bayesian information criterion (BIC) -- to models consising of states of fixed rank and datasets such as are currently produced in multiple ions experiments. We test the performance of AIC and BIC on randomly chosen low rank states of 4 ions, and study the dependence of the selected rank with the number of measurement repetitions for one ion states. We then apply the methods to real data from a 4 ions experiment aimed at creating a Smolin state of rank 4. The two methods indicate that the optimal model for describing the data lies between ranks 6 and 9, and the Pearson $\chi^{2}$ test is applied to validate this conclusion. Additionally we find that the mean square error of the maximum likelihood estimator for pure states is close to that of the optimal over all possible measurements.Comment: 24 pages, 6 figures, 3 table