The Cube Recurrence

We construct a combinatorial model that is described by the cube recurrence, a nonlinear recurrence relation introduced by Propp, which generates families of Laurent polynomials indexed by points in $\mathbb{Z}^3$. In the process, we prove several conjectures of Propp and of Fomin and Zelevinsky, and we obtain a combinatorial interpretation for the terms of Gale-Robinson sequences. We also indicate how the model might be used to obtain some interesting results about perfect matchings of certain bipartite planar graphs

What Does It Take for a Family to Afford to Pay for Health Care?

Addresses how much Californians can afford to pay for health care based on their current insurance premiums and out-of-pocket expenses as well as other basic necessities, such as housing, child care, transportation, food, and taxes

Outer Retinal Structure in Best Vitelliform Macular Dystrophy

Importance Demonstrating the utility of adaptive optics scanning light ophthalmoscopy (AOSLO) to assess outer retinal structure in Best vitelliform macular dystrophy (BVMD). Objective To characterize outer retinal structure in BVMD using spectral-domain optical coherence tomography (SD-OCT) and AOSLO. Design, Setting, and Participants Prospective, observational case series. Four symptomatic members of a family with BVMD with known BEST1 mutation were recruited at the Advanced Ocular Imaging Program research lab at the Medical College of Wisconsin Eye Institute, Milwaukee. Intervention Thickness of 2 outer retinal layers corresponding to photoreceptor inner and outer segments was measured using SD-OCT. Photoreceptor mosaic AOSLO images within and around visible lesions were obtained, and cone density was assessed in 2 subjects. Main Outcome and Measure Photoreceptor structure. Results Each subject was at a different stage of BVMD, with photoreceptor disruption evident by AOSLO at all stages. When comparing SD-OCT and AOSLO images from the same location, AOSLO images allowed for direct assessment of photoreceptor structure. A variable degree of retained photoreceptors was seen within all lesions. The photoreceptor mosaic immediately adjacent to visible lesions appeared contiguous and was of normal density. Fine hyperreflective structures were visualized by AOSLO, and their anatomical orientation and size were consistent with Henle fibers. Conclusions and Relevance The AOSLO findings indicate that substantial photoreceptor structure persists within active lesions, accounting for good visual acuity in these patients. Despite previous reports of diffuse photoreceptor outer segment abnormalities in BVMD, our data reveal normal photoreceptor structure in areas adjacent to clinical lesions. This study demonstrates the utility of AOSLO for understanding the spectrum of cellular changes that occur in inherited degenerations such as BVMD. Photoreceptors are often significantly affected at various stages of inherited degenerations, and these changes may not be readily apparent with current clinical imaging instrumentation

The HealthPia GlucoPack™ Diabetes Phone: A Usability Study

This is a copy of an article published in Diabetes Technology & Therapeutics copyright Mary Ann Liebert, Inc.; Diabetes Technology & Therapeutics is available online at: http://online.liebertpub.com.Background: Type I diabetes is a common chronic disease of childhood. Both the growing influence of peers and the shifting away from parental influence have been implicated as prime elements contributing to poor glycemic outcomes in adolescents. Mobile technology that can be directed towards providing self-management support and modifying potentially negative child parent interaction holds promise to improve control in adolescents with diabetes. Methods: HealthPia, Inc. (Palisades Park, NJ) has developed a prototype system, the HealthPia GlucoPack™ Diabetes Monitoring System, which integrates a small blood glucose monitoring device into the battery pack of a cell phone. A pilot study used mixed quantitative and qualitative methods to evaluate user satisfaction with the integrated system, including the potential of the device to transmit self-monitoring data to a website for review and analysis by clinicians, parents, and patients. Results: Adolescents in our study liked the integration of the two technologies and agreed that the glucometer was easy to use and that the tool was useful in the management of their diabetes. Conclusions: Future work will focus on the utilization of the diabetes phone as a component of a care delivery system for adolescents with diabetes, including involvement of the health care team and enhancement of the web services that support the use of the phone

Recommendations for a ‘Wellbeing Curriculum’ to Mitigate Undergraduate Psychological Distress Associated with Lack of Careers Confidence and Poor University Engagement

To foster a ‘wellbeing curriculum’ in a climate with an increasingly competitive graduate jobs market, we believe it is critical to support undergraduate career development and to develop positive peer and educator relationships, particularly for non vocational degree programs. However, these relationships between undergraduate wellbeing and their career development or peer/educator relationships have not been specifically examined. This study used a mixed methods approach to examine if poor career development or university engagement (quality of relationships with peers or educators, use of the university careers and counselling services, time studying) were associated with psychological distress for students in non vocational degree programs. Undergraduates (biomedical science; n=1100) from five Australian universities participated in a survey to investigate relationships between psychological distress, as determined by their responses to the Depression, Anxiety and Stress Scales, and their career development or university engagement. Almost half of the students lacked confidence in their ‘future employment and job prospects’. Students’ psychological distress was significantly correlated with lack of confidence with their career development, poor relationships with their peers and educators and little use of the counselling service. Further exploration of these factors in student focus groups highlighted stress associated with academic competition between students and a critical need for undergraduate career development, especially industry placements. We provide pivotal recommendations to promote undergraduate and educator wellbeing, by developing a ‘wellbeing curriculum’ that supports career development and positive relationships between students and their peers and educators, particularly vital for non vocational degrees

Microscopic Inner Retinal Hyper-reflective Phenotypes in Retinal and Neurologic Disease

Purpose. We surveyed inner retinal microscopic features in retinal and neurologic disease using a reflectance confocal adaptive optics scanning light ophthalmoscope (AOSLO). Methods. Inner retinal images from 101 subjects affected by one of 38 retinal or neurologic conditions and 11 subjects with no known eye disease were examined for the presence of hyper-reflective features other than vasculature, retinal nerve fiber layer, and foveal pit reflex. The hyper-reflective features in the AOSLO images were grouped based on size, location, and subjective texture. Clinical imaging, including optical coherence tomography (OCT), scanning laser ophthalmoscopy, and fundus photography was analyzed for comparison. Results. Seven categories of hyper-reflective inner retinal structures were identified, namely punctate reflectivity, nummular (disc-shaped) reflectivity, granular membrane, waxy membrane, vessel-associated membrane, microcysts, and striate reflectivity. Punctate and nummular reflectivity also was found commonly in normal volunteers, but the features in the remaining five categories were found only in subjects with retinal or neurologic disease. Some of the features were found to change substantially between follow up imaging months apart. Conclusions. Confocal reflectance AOSLO imaging revealed a diverse spectrum of normal and pathologic hyper-reflective inner and epiretinal features, some of which were previously unreported. Notably, these features were not disease-specific, suggesting that they might correspond to common mechanisms of degeneration or repair in pathologic states. Although prospective studies with larger and better characterized populations, along with imaging of more extensive retinal areas are needed, the hyper-reflective structures reported here could be used as disease biomarkers, provided their specificity is studied further

Using a cell phone-based glucose monitoring system for adolescent diabetes management

INTRODUCTION: Mobile technology may be useful in addressing several issues in adolescent diabetes management. PURPOSE: To assess the feasibility and acceptability of a cell phone glucose monitoring system for adolescents with type 1 diabetes and their parents. METHODS: The authors recruited patients with type 1 diabetes who had been diagnosed for at least 1 year. Each adolescent used the system for 6 months, filling out surveys every 3 months to measure their usability and satisfaction with the cell phone glucose monitoring system, as well as how use of the system might affect quality of family functioning and diabetes management. RESULTS: Adolescents reported positive feelings about the technology and the service, even though a concerning number of them had significant technical issues that affected continued use of the device. Nearly all thought that the clinic involvement in monitoring testing behavior was quite acceptable. The use of the Glucophone™ did not, however, significantly change the quality of life of the adolescents, their level of conflict with their parents, their reported self-management of diabetes, or their average glycemic control within the short time frame of the study. CONCLUSIONS: As a feasibility study of the technology, this work was successful in demonstrating that cell phone glucose monitoring technology can be used in an adolescent population to track and assist in self-monitoring behavior. The authors speculate that explicitly attempting to change behavior, perhaps with the use of behavioral contracts, would enhance the technology's ability to improve outcomes

Spin/disorder correlations and duality in the c=1/2 string

We use the method of discrete loop equations to calculate exact correlation functions of spin and disorder operators on the sphere and on the boundary of a disk in the $c = 1/2$ string, both in the Ising and dual Ising matrix model formulations. For both the Ising and dual Ising theories the results on the sphere are in agreement with the KPZ/DDK scaling predictions based on Liouville theory; the results on the disk agree with the scaling predictions of Martinec, Moore, and Seiberg for boundary operators. The calculation of Ising disorder correlations on the sphere requires the use of boundary variables introduced in [hep-th/9510199], which have no matrix model analog. A subtlety in the calculation on the disk arises because the expansions of the correlation functions have leading singular terms which are nonuniversal; we show that this issue may be resolved by using separate cosmological constants for each boundary domain. These results give evidence that the Kramers-Wannier duality symmetry of the $c = 1/2$ conformal field theory survives coupling to quantum gravity, implying a duality symmetry of the $c = 1/2$ string even in the presence of boundary operators.Comment: 19 pages, LaTeX; final publication versio

Database management and analysis of fisheries in Illinois: Final report, 1 March 1999-28 February 2002

Issued May 2002; F-69-RReport issued on: May 200