Relationship Between Diabetes, Stress, and Self-Management to Inform Chronic Disease Product Development: Retrospective Cross-Sectional Study

Background

Technology is rapidly advancing our understanding of how people with diabetes mellitus experience stress.

Objective

The aim of this study was to explore the relationship between stress and sequelae of diabetes mellitus within a unique data set composed of adults enrolled in a digital diabetes management program, Livongo, in order to inform intervention and product development.

Methods

Participants included 3263 adults under age 65 who were diagnosed with diabetes mellitus and had access to Livongo through their employer between June 2015 and August 2018. Data were collected at time of enrollment and 12 months thereafter, which included demographic information, glycemic control, presence of stress, diabetes distress, diabetes empowerment, behavioral health diagnosis, and utilization of behavioral health-related medication and services. Analysis of variance and chi-square tests compared variables across groups that were based on presence of stress and behavioral health diagnosis or utilization.

Results

Fifty-five percent of participants (1808/3263) reported stress at the time of at least 1 blood glucose reading. Fifty-two percent of participants (940/1808) also received at least 1 behavioral health diagnosis or intervention. Compared to their peers, participants with stress reported greater diabetes distress, lower diabetes empowerment, greater insulin use, and poorer glycemic control. Participants with stress and a behavioral health diagnosis/utilization additionally had higher body mass index and duration of illness.

Conclusions

Stress among people with diabetes mellitus is associated with reduced emotional and physical health. Digital products that focus on the whole person by offering both diabetes mellitus self-management tools and behavioral health skills and support can help improve disease-specific and psychosocial outcomes.

Advances in PTSD Treatment Delivery: Review of Findings and Clinical Considerations for the Use of Telehealth Interventions for PTSD

Purpose of review

Effective treatments for posttraumatic stress disorder (PTSD) remain underutilized and individuals with PTSD often have difficulty accessing care. Telehealth, particularly clinical videoconferencing (CVT), can overcome barriers to treatment and increase access to care for individuals with PTSD. The purpose of this review is to summarize the literature on the delivery of PTSD treatments through office-based and home-based videoconferencing, and outline areas for future research.

Recent findings

Evidence-based PTSD treatments delivered through office-based and home-based CVT have been studied in pilot studies, non-randomized trials, and randomized clinical trials. The studies have consistently demonstrated feasibility and acceptability of these modalities as well as significant reduction in PTSD symptoms, non-inferior outcomes, and comparable dropout rates when compared with traditional face-to-face office-based care. Finally, it has been shown that using CVT does not compromise the therapeutic process.

Summary

Office-based and home-based CVT can be used to deliver PTSD treatments while retaining efficacy and therapeutic process. The use of these modalities can increase the number of individuals that can access efficacious PTSD care.

1169Interim analysis of data from a long-term, extension trial of tafamidis meglumine in patients with transthyretin amyloid cardiomyopathy

Background

Transthyretin amyloid cardiomyopathy (ATTR-CM), is an underdiagnosed, fatal disease caused by the deposition of transthyretin amyloid fibrils in the heart leading to heart failure. The Transthyretin Cardiomyopathy Clinical Trial (ATTR-ACT), an international, multi-center, double-blind, placebo-controlled, randomized study, demonstrated the efficacy and safety of tafamidis treatment for patients with ATTR-CM due to variant (ATTRm) or wild-type (ATTRwt) TTR.

Purpose

This is a pooled analysis of data from ATTR-ACT and interim data from the ongoing, long-term, extension study to evaluate longer term data on the efficacy of tafamidis in patients with ATTR-CM.

Methods

Patients who completed ATTR-ACT (which had a duration of 30 months) were eligible to be enrolled in a long-term, extension study in which patients either continued to receive tafamidis meglumine at the same dose (the tafamidis/tafamidis [T/T] group) or, for patients previously treated with placebo, were randomised (in a 1:2 ratio) to tafamidis meglumine 20 mg or 80 mg (the placebo/tafamidis [P/T] group) for up to 60 months. The primary efficacy outcome was all-cause mortality. This analysis combined data from the completed ATTR-ACT with interim data from the extension study (cut-off date: 15 Feb, 2018), and included patients treated with tafamidis meglumine across the two studies with a median follow up of 36 months.

Results

All-cause mortality was significantly lower in the T/T group (n=264; 88 events, 33.3%) compared with the P/T group (n=177; 88 events, 50.3%); hazard ratio (95% CI), 0.64 (0.47, 0.85); P=0.001. In the subgroup of ATTRwt patients, all-cause mortality was significantly reduced in the T/T group (55/201; 27.4%) compared with the P/T group (60/134; 44.8%); 0.64 (0.44, 0.92); P=0.002. In the 106 (24.0%) ATTRm patients, there was a trend towards a reduction in all-cause mortality in the T/T group (33/63; 52.4%) compared with the P/T group (29/43; 67.4%); 0.66 (0.39, 1.09); P=0.17. In patients who were NYHA Class I or II at baseline, all-cause mortality was significantly reduced in the T/T group (38/186; 20.4%) compared with the P/T group (45/114; 39.5%); 0.49 (0.32, 0.75); P=0.001. In those patients with more severe symptoms at baseline (NYHA Class III), there were fewer deaths in the T/T group (50/78; 64.1%) compared with the P/T group (44/63; 69.8%); 0.80 (0.53, 1.21), but this difference was not statistically significant (P=0.50).

Conclusions

In ATTR-ACT, tafamidis was shown to significantly improve survival, functional capacity, and quality of life in patients with ATTR-CM. This pooled analysis with data from the ongoing extension study further supports the efficacy of tafamidis in patients over a longer period of time and the importance of early diagnosis and treatment.

Acknowledgement/Funding

This study was sponsored by Pfizer.

Expert Consensus Survey on Digital Health Tools for Patients With Serious Mental Illness: Optimizing for User Characteristics and User Support

BACKGROUND

Digital technology is increasingly being used to enhance health care in various areas of medicine. In the area of serious mental illness, it is important to understand the special characteristics of target users that may influence motivation and competence to use digital health tools, as well as the resources and training necessary for these patients to facilitate the use of this technology.

OBJECTIVE

The aim of this study was to conduct a quantitative expert consensus survey to identify key characteristics of target users (patients and health care professionals), barriers and facilitators for appropriate use, and resources needed to optimize the use of digital health tools in patients with serious mental illness.

METHODS

A panel of 40 experts in digital behavioral health who met the participation criteria completed a 19-question survey, rating predefined responses on a 9-point Likert scale. Consensus was determined using a chi-square test of score distributions across three ranges (1-3, 4-6, 7-9). Categorical ratings of first, second, or third line were designated based on the lowest category into which the CI of the mean ratings fell, with a boundary >6.5 for first line. Here, we report experts' responses to nine questions (265 options) that focused on (1) user characteristics that would promote or hinder the use of digital health tools, (2) potential benefits or motivators and barriers or unintended consequences of digital health tool use, and (3) support and training for patients and health care professionals.

RESULTS

Among patient characteristics most likely to promote use of digital health tools, experts endorsed interest in using state-of-the-art technology, availability of necessary resources, good occupational functioning, and perception of the tool as beneficial. Certain disease-associated signs and symptoms (eg, more severe symptoms, substance abuse problems, and a chaotic living situation) were considered likely to make it difficult for patients to use digital health tools. Enthusiasm among health care professionals for digital health tools and availability of staff and equipment to support their use were identified as variables to enable health care professionals to successfully incorporate digital health tools into their practices. The experts identified a number of potential benefits of and barriers to use of digital health tools by patients and health care professionals. Experts agreed that both health care professionals and patients would need to be trained in the use of these new technologies.

CONCLUSIONS

These results provide guidance to the mental health field on how to optimize the development and deployment of digital health tools for patients with serious mental illness.

PTSD Coach around the world

Posttraumatic stress disorder (PTSD) is a global public health problem. Unfortunately, many individuals with PTSD do not receive professional care due to a lack of available providers, stigma about mental illness, and other concerns. Technology-based interventions, including mobile phone applications (apps) may be a viable means of surmounting such barriers and reaching and helping those in need. Given this potential, in 2011 the U.S Veterans Affairs National Center for PTSD released PTSD Coach, a mobile app intended to provide psycho-education and self-management tools for trauma survivors with PTSD symptoms. Emerging research on PTSD Coach demonstrates high user satisfaction, feasibility, and improvement in PTSD symptoms and other psychosocial outcomes. A model of openly sharing the app's source code and content has resulted in versions being created by individuals in six other countries: Australia, Canada, The Netherlands, Germany, Sweden, and Denmark. These versions are described, highlighting their significant adaptations, enhancements, and expansions to the original PTSD Coach app as well as emerging research on them. It is clear that the sharing of app source code and content has benefited this emerging PTSD Coach community, as well as the populations they are targeting. Despite this success, challenges remain especially reaching trauma survivors in areas where few or no other mental health resources exist.

VA mobile apps for PTSD and related problems: public health resources for veterans and those who care for them

Many public health agencies, including the U.S. Department of Veterans Affairs (VA), have identified the use of mobile technologies as an essential part of a larger strategy to address major public health challenges. The VA's National Center for PTSD (NCPTSD), in collaboration with VA's Office of Mental Health and Suicide Prevention and the Defense Health Agency inside the U.S. Department of Defense (DoD), has been involved in the development, evaluation, and testing of 15 mobile apps designed specifically to address the needs and concerns of veterans and others experiencing symptoms of posttraumatic stress disorder (PTSD). These applications include seven treatment-companion apps (designed to be used with a provider, in conjunction with an evidence-based therapy) and eight self-management apps (designed to be used independently or as an adjunct or extender of traditional care). There is growing evidence for the efficacy of several of these apps for reducing PTSD and other symptoms, and studies of providers demonstrate that the apps are engaging, easy-to-use, and provide a relative advantage to traditional care without apps. While publicly available apps do not collect or share personal data, VA has created research-enabled versions of many of its mental health apps to enable ongoing product enhancement and continuous measurement of the value of these tools to veterans and frontline providers. VA and DoD are also collaborating on provider-based implementation networks to enable clinicians to optimize implementation of mobile technologies in care. Although there are many challenges to developing and integrating mHealth into care, including cost, privacy, and the need for additional research, mobile mental health technologies are likely here to stay and have the potential to reach large numbers of those with unmet mental health needs, including PTSD-related concerns.

Development and refinement of a clinician intervention to facilitate primary care patient use of the PTSD Coach app

Posttraumatic stress disorder (PTSD) is common and undertreated among Veterans Affairs (VA) primary care patients. A brief primary care intervention combining clinician support with a self-management mobile app (Clinician-Supported PTSD Coach, CS-PTSD Coach) may improve patient outcomes. This study developed and refined an intervention to provide clinician support to facilitate use of the PTSD Coach app and gathered VA provider and patient qualitative and quantitative feedback on CS-PTSD Coach to investigate preliminary acceptability and implementation barriers/facilitators. VA primary care providers and mental health leadership (N = 9) completed a survey and interview regarding implementation barriers and facilitators structured according to the Consolidated Framework for Implementation Research (CFIR). Clinicians who delivered CS-PTSD Coach (N = 3) and patients (N = 9) who received it provided feedback on the intervention and implementation process. CS-PTSD Coach has high provider and patient acceptability. Important implementation factors included that CS-PTSD Coach be compatible with the clinics' current practices, have low complexity to implement, be perceived to address patient needs, and have strong support from leadership. Diverse factors related to CS-PTSD Coach delivery facilitate implementation, provide an opportunity to problem-solve barriers, and improve integration of the intervention into primary care.

A randomized controlled trial of a smartphone app for posttraumatic stress disorder symptoms

OBJECTIVE

Posttraumatic stress disorder (PTSD) is highly prevalent in the population, but relatively few affected individuals receive treatment for it. Smartphone applications (apps) could help address this unmet need by offering sound psychoeducational information and evidence-based cognitive behavioral coping tools. We conducted a randomized controlled trial to assess the efficacy of a free, publicly available smartphone app (PTSD Coach) for self-management of PTSD symptoms.

METHOD

One hundred 20 participants who were an average of 39 years old, mostly women (69.2%) and White (66.7%), recruited primarily through online advertisements, were randomized to either a PTSD Coach (n = 62) or a waitlist condition (n = 58) for 3 months. Web-administered self-report measures of PTSD, PTSD symptom coping self-efficacy, depression, and psychosocial functioning were conducted at baseline, posttreatment, and 3 months following treatment.

RESULTS

Following the intent-to-treat principle, repeated-measures analyses of variance (ANOVAs) revealed that at posttreatment, PTSD Coach participants had significantly greater improvements in PTSD symptoms (p = .035), depression symptoms (p = .005), and psychosocial functioning (p = .007) than did waitlist participants; however, at posttreatment, there were no significant mean differences in outcomes between conditions. A greater proportion of PTSD Coach participants achieved clinically significant PTSD symptom improvement (p = .018) than waitlist participants.

CONCLUSION

PTSD Coach use resulted in significantly greater improvements in PTSD symptoms and other outcomes relative to a waitlist condition. Given the ubiquity of smartphones, PTSD Coach may provide a wide-reaching, convenient public health intervention for individuals with PTSD symptoms who are not receiving care. (PsycINFO Database Record

Clinician perceptions of using a smartphone app with prolonged exposure therapy

Clinician perceptions of clinical innovations affect their adoption and spread. This study investigated mental health clinicians' (n = 163) perceptions of a patient-facing smartphone application (app) for prolonged exposure (PE) therapy for posttraumatic stress disorder, before its public release. After reading a description of the app, participants rated perceptions of it based on diffusion of innovations theory constructs. Perceptions were generally favorable regarding the app's relative advantage over existing PE practices, compatibility with their values and needs, and complexity. Age (<40 years), smartphone ownership, and having used apps in care related to more favorable perceptions. Smartphone ownership, relative advantage, and complexity significantly predicted intention to use the app if it were available. These findings suggest that clinicians are receptive to using a PE app and that dissemination efforts should target sub-groups of PE clinicians to maximize adoption.

Acoustic buffeting by infrasound in a low vibration facility

Measurement instruments and fabrication tools with spatial resolution on the atomic scale require facilities that mitigate the impact of vibration sources in the environment. One approach to protection from vibration in a building's foundation is to place the instrument on a massive inertia block, supported on pneumatic isolators. This opens the questions of whether or not a massive floating block is susceptible to acoustic forces, and how to mitigate the effects of any such acoustic buffeting. Here this is investigated with quantitative measurements of vibrations and sound pressure, together with finite element modeling. It is shown that a particular concern, even in a facility with multiple acoustic enclosures, is the excitation of the lowest fundamental acoustic modes of the room by infrasound in the low tens of Hz range, and the efficient coupling of the fundamental room modes to a large inertia block centered in the room.

A randomized controlled pilot study of CBT-I Coach: Feasibility, acceptability, and potential impact of a mobile phone application for patients in cognitive behavioral therapy for insomnia

There has been growing interest in utilizing mobile phone applications (apps) to enhance traditional psychotherapy. Previous research has suggested that apps may facilitate patients' completion of cognitive behavioral therapy for insomnia (CBT-I) tasks and potentially increase adherence. This randomized clinical trial pilot study ( n = 18) sought to examine the feasibility, acceptability, and potential impact on adherence and sleep outcomes related to CBT-I Coach use. All participants were engaged in CBT-I, with one group receiving the app as a supplement and one non-app group. We found that patients consistently used the app as intended, particularly the sleep diary and reminder functions. They reported that it was highly acceptable to use. Importantly, the app did not compromise or undermine benefits of cognitive behavioral therapy for insomnia and patients in both groups had significantly improved sleep outcomes following treatment.

CBT-I Coach: A Description and Clinician Perceptions of a Mobile App for Cognitive Behavioral Therapy for Insomnia

STUDY OBJECTIVES

This paper describes CBT-I Coach, a patient-facing smartphone app designed to enhance cognitive behavioral therapy for insomnia (CBT-I). It presents findings of two surveys of U.S. Department of Veterans Affairs (VA) CBT-I trained clinicians regarding their perceptions of CBT-I Coach before it was released (n = 138) and use of it two years after it was released (n = 176).

METHODS

VA-trained CBT-I clinicians completed web-based surveys before and two years after CBT-I Coach was publicly released.

RESULTS

Prior to CBT-I Coach release, clinicians reported that it was moderately to very likely that the app could improve care and a majority (87.0%) intended to use it if it were available. Intention to use the app was predicted by smartphone ownership (β = 0.116, p < 0.05) and perceptions of relative advantage to existing CBT-I practices (β = 0.286, p < 0.01), compatibility with their own needs and values (β = 0.307, p < 0.01), and expectations about the complexity of the app (β = 0.245, p < 0.05). Two years after CBT-I Coach became available, 59.9% of participants reported using it with patients and had favorable impressions of its impact on homework adherence and outcomes.

CONCLUSIONS

Findings suggest that before release, CBT-I Coach was perceived to have potential to enhance CBT-I and address common adherence issues and clinicians would use it. These results are reinforced by findings two years after it was released suggesting robust uptake and favorable perceptions of its value.

Feasibility, acceptability, and potential efficacy of the PTSD Coach app: A pilot randomized controlled trial with community trauma survivors

OBJECTIVE

Posttraumatic stress disorder (PTSD) is a major public health concern. Although effective treatments exist, affected individuals face many barriers to receiving traditional care. Smartphones are carried by nearly 2 thirds of the U.S. population, offering a promising new option to overcome many of these barriers by delivering self-help interventions through applications (apps). As there is limited research on apps for trauma survivors with PTSD symptoms, we conducted a pilot feasibility, acceptability, and potential efficacy trial of PTSD Coach, a self-management smartphone app for PTSD.

METHOD

A community sample of trauma survivors with PTSD symptoms (N = 49) were randomized to 1 month using PTSD Coach or a waitlist condition. Self-report assessments were completed at baseline, postcondition, and 1-month follow-up. Following the postcondition assessment, waitlist participants were crossed-over to receive PTSD Coach.

RESULTS

Participants reported using the app several times per week, throughout the day across multiple contexts, and endorsed few barriers to use. Participants also reported that PTSD Coach components were moderately helpful and that they had learned tools and skills from the app to manage their symptoms. Between conditions effect size estimates were modest (d = -0.25 to -0.33) for PTSD symptom improvement, but not statistically significant.

CONCLUSIONS

Findings suggest that PTSD Coach is a feasible and acceptable intervention. Findings regarding efficacy are less clear as the study suffered from low statistical power; however, effect size estimates, patterns of within group findings, and secondary analyses suggest that further development and research on PTSD Coach is warranted. (PsycINFO Database Record

Using PTSD Coach in primary care with and without clinician support: a pilot randomized controlled trial

OBJECTIVE

This study aims to evaluate the feasibility and potential effectiveness of two approaches to using the PTSD Coach mobile application in primary care: Self-Managed PTSD Coach and Clinician-Supported PTSD Coach. This study also aims to gather preliminary data to investigate if clinician support improves the benefits of using PTSD Coach on posttraumatic stress disorder (PTSD) severity and specialty mental healthcare utilization.

METHOD

Twenty primary care veterans with PTSD symptoms were randomized to either Self-Managed PTSD Coach consisting of one 10-min session providing instructions for application use or Clinician-Supported PTSD Coach consisting of four 20-min sessions focused on setting symptom reduction goals and helping veterans fully engage with application content.

RESULTS

Research procedures and intervention conditions appear feasible as indicated by high rates of assessment and intervention retention and high clinician fidelity and satisfaction. Both treatments resulted in reductions in PTSD symptoms, with 7 Clinician-Supported PTSD Coach and 3 Self-Managed PTSD Coach participants reporting clinically significant improvements. Clinician-Supported PTSD Coach resulted in more specialty PTSD care use postintervention and possibly greater reductions in PTSD symptoms.

CONCLUSIONS

Both PTSD Coach interventions are feasible and potentially helpful. The addition of clinician support appears to increase the effectiveness of self-management alone. A larger-scale randomized controlled trial is warranted to confirm these encouraging preliminary findings.

Comparison of the PTSD Checklist (PCL) Administered via a Mobile Device Relative to a Paper Form

Mobile devices are increasingly used to administer self-report measures of mental health symptoms. There are significant differences, however, in the way that information is presented on mobile devices compared to the traditional paper forms that were used to administer such measures. Such differences may systematically alter responses. The present study evaluated if and how responses differed for a self-report measure, the PTSD Checklist (PCL), administered via mobile device relative to paper and pencil. Participants were 153 trauma-exposed individuals who completed counterbalanced administrations of the PCL on a mobile device and on paper. PCL total scores (d = 0.07) and item responses did not meaningfully or significantly differ across administrations. Power was sufficient to detect a difference in total score between administrations determined by prior work of 3.46 with a d = 0.23. The magnitude of differences between administration formats was unrelated to prior use of mobile devices or participant age. These findings suggest that responses to self-report measures administered via mobile device are equivalent to those obtained via paper and they can be used with experienced as well as naïve users of mobile devices.

A Virtual Hope Box smartphone app as an accessory to therapy: proof-of-concept in a clinical sample of veterans

A "Hope Box" is a therapeutic tool employed by clinicians with patients who are having difficulty coping with negative thoughts and stress, including patients who may be at risk of suicide or nonsuicidal self-harm. We conducted a proof-of-concept test of a "Virtual" Hope Box (VHB)-a smartphone app that delivers patient-tailored coping tools. Compared with a conventional hope box integrated into VA behavioral health treatment, high-risk patients and their clinicians used the VHB more regularly and found the VHB beneficial, useful, easy to set up, and said they were likely to use the VHB in the future and recommend the VHB to peers.

mHealth in the Wild: Using Novel Data to Examine the Reach, Use, and Impact of PTSD Coach

BACKGROUND

A majority of Americans (58%) now use smartphones, making it possible for mobile mental health apps to reach large numbers of those who are living with untreated, or under-treated, mental health symptoms. Although early trials suggest positive effects for mobile health (mHealth) interventions, little is known about the potential public health impact of mobile mental health apps.

OBJECTIVE

The purpose of this study was to characterize reach, use, and impact of "PTSD Coach", a free, broadly disseminated mental health app for managing posttraumatic stress disorder (PTSD) symptoms.

METHODS

Using a mixed-methods approach, aggregate mobile analytics data from 153,834 downloads of PTSD Coach were analyzed in conjunction with 156 user reviews.

RESULTS

Over 60% of users engaged with PTSD Coach on multiple occasions (mean=6.3 sessions). User reviews reflected gratitude for the availability of the app and being able to use the app specifically during moments of need. PTSD Coach users reported relatively high levels of trauma symptoms (mean PTSD Checklist Score=57.2, SD=15.7). For users who chose to use a symptom management tool, distress declined significantly for both first-time users (mean=1.6 points, SD=2.6 on the 10-point distress thermometer) and return-visit users (mean=2.0, SD=2.3). Analysis of app session data identified common points of attrition, with only 80% of first-time users reaching the app's home screen and 37% accessing one of the app's primary content areas.

CONCLUSIONS

These findings suggest that PTSD Coach has achieved substantial and sustained reach in the population, is being used as intended, and has been favorably received. PTSD Coach is a unique platform for the delivery of mobile mental health education and treatment, and continuing evaluation and improvement of the app could further strengthen its public health impact.

Intermodal energy transfer in a tapered optical fiber: optimizing transmission

We present an experimental and theoretical study of the energy transfer between modes during the tapering process of an optical nanofiber through spectrogram analysis. The results allow optimization of the tapering process, and we measure transmission in excess of 99.95% for the fundamental mode. We quantify the adiabaticity condition through calculations and place an upper bound on the amount of energy transferred to other modes at each step of the tapering, giving practical limits to the tapering angle.

A low-loss photonic silica nanofiber for higher-order modes

Optical nanofibers confine light to subwavelength scales, and are of interest for the design, integration, and interconnection of nanophotonic devices. Here we demonstrate high transmission (> 97%) of the first family of excited modes through a 350 nm radius fiber, by appropriate choice of the fiber and precise control of the taper geometry. We can design the nanofibers so that these modes propagate with most of their energy outside the waist region. We also present an optical setup for selectively launching these modes with less than 1% fundamental mode contamination. Our experimental results are in good agreement with simulations of the propagation. Multimode optical nanofibers expand the photonic toolbox, and may aid in the realization of a fully integrated nanoscale device for communication science, laser science or other sensing applications.

Making sense of mobile health data: an open architecture to improve individual- and population-level health

Mobile phones and devices, with their constant presence, data connectivity, and multiple intrinsic sensors, can support around-the-clock chronic disease prevention and management that is integrated with daily life. These mobile health (mHealth) devices can produce tremendous amounts of location-rich, real-time, high-frequency data. Unfortunately, these data are often full of bias, noise, variability, and gaps. Robust tools and techniques have not yet been developed to make mHealth data more meaningful to patients and clinicians. To be most useful, health data should be sharable across multiple mHealth applications and connected to electronic health records. The lack of data sharing and dearth of tools and techniques for making sense of health data are critical bottlenecks limiting the impact of mHealth to improve health outcomes. We describe Open mHealth, a nonprofit organization that is building an open software architecture to address these data sharing and "sense-making" bottlenecks. Our architecture consists of open source software modules with well-defined interfaces using a minimal set of common metadata. An initial set of modules, called InfoVis, has been developed for data analysis and visualization. A second set of modules, our Personal Evidence Architecture, will support scientific inferences from mHealth data. These Personal Evidence Architecture modules will include standardized, validated clinical measures to support novel evaluation methods, such as n-of-1 studies. All of Open mHealth's modules are designed to be reusable across multiple applications, disease conditions, and user populations to maximize impact and flexibility. We are also building an open community of developers and health innovators, modeled after the open approach taken in the initial growth of the Internet, to foster meaningful cross-disciplinary collaboration around new tools and techniques. An open mHealth community and architecture will catalyze increased mHealth efficiency, effectiveness, and innovation.

Scanning tunneling spectroscopy and vortex imaging in the iron pnictide superconductor BaFe1.8Co0.2As2

We present an atomic resolution scanning tunneling spectroscopy study of superconducting BaFe1.8Co0.2As2 single crystals in magnetic fields up to 9 T. At zero field, a single gap with coherence peaks at Delta=6.25 meV is observed in the density of states. At 9 and 6 T, we image a disordered vortex lattice, consistent with isotropic, single flux quantum vortices. Vortex locations are uncorrelated with strong-scattering surface impurities, demonstrating bulk pinning. The vortex-induced subgap density of states fits an exponential decay from the vortex center, from which we extract a coherence length xi=27.6+/-2.9 A, corresponding to an upper critical field Hc2=43 T.

Coincidence of checkerboard charge order and antinodal state decoherence in strongly underdoped superconducting Bi2Sr2CaCu2O8 + delta)

The doping dependence of nanoscale electronic structure in superconducting Bi(2)Sr(2)CaCu(2)O(8 + delta) is studied by scanning tunneling microscopy. At all dopings, the low energy density-of-states modulations are analyzed according to a simple model of quasiparticle interference and found to be consistent with Fermi-arc superconductivity. The superconducting coherence peaks, ubiquitous in near-optimal tunneling spectra, are destroyed with strong underdoping and a new spectral type appears. Exclusively in regions exhibiting this new spectrum, we find local "checkerboard" charge ordering of high energy states, with a wave vector of Q = (+/- 2pi/4.5a(0),0); (0, +/- 2pi/4.5a(0)) +/- 15%. Surprisingly, this spatial ordering of high energy states coexists harmoniously with the low energy Bogoliubov quasiparticle states.

Relating atomic-scale electronic phenomena to wave-like quasiparticle states in superconducting Bi2Sr2CaCu2O8+delta

The electronic structure of simple crystalline solids can be completely described in terms either of local quantum states in real space (r-space), or of wave-like states defined in momentum-space (k-space). However, in the copper oxide superconductors, neither of these descriptions alone may be sufficient. Indeed, comparisons between r-space and k-space studies of Bi2Sr2CaCu2O8+delta (Bi-2212) reveal numerous unexplained phenomena and apparent contradictions. Here, to explore these issues, we report Fourier transform studies of atomic-scale spatial modulations in the Bi-2212 density of states. When analysed as arising from quasiparticle interference, the modulations yield elements of the Fermi-surface and energy gap in agreement with photoemission experiments. The consistency of numerous sets of dispersing modulations with the quasiparticle interference model shows that no additional order parameter is required. We also explore the momentum-space structure of the unoccupied states that are inaccessible to photoemission, and find strong similarities to the structure of the occupied states. The copper oxide quasiparticles therefore apparently exhibit particle-hole mixing similar to that of conventional superconductors. Near the energy gap maximum, the modulations become intense, commensurate with the crystal, and bounded by nanometre-scale domains. Scattering of the antinodal quasiparticles is therefore strongly influenced by nanometre-scale disorder.

Imaging quasiparticle interference in Bi2Sr2CaCu2O8+delta

Scanning tunneling spectroscopy of the high-Tc superconductor Bi2Sr2CaCu2O8+delta reveals weak, incommensurate, spatial modulations in the tunneling conductance. Images of these energy-dependent modulations are Fourier analyzed to yield the dispersion of their wavevectors. Comparison of the dispersions with photoemission spectroscopy data indicates that quasiparticle interference, due to elastic scattering between characteristic regions of momentum-space, provides a consistent explanation for the conductance modulations, without appeal to another order parameter. These results refocus attention on quasiparticle scattering processes as potential explanations for other incommensurate phenomena in the cuprates. The momentum-resolved tunneling spectroscopy demonstrated here also provides a new technique with which to study quasiparticles in correlated materials.

Imaging the granular structure of high-Tc superconductivity in underdoped Bi2Sr2CaCu2O8+delta

Granular superconductivity occurs when microscopic superconducting grains are separated by non-superconducting regions; Josephson tunnelling between the grains establishes the macroscopic superconducting state. Although crystals of the copper oxide high-transition-temperature (high-Tc) superconductors are not granular in a structural sense, theory suggests that at low levels of hole doping the holes can become concentrated at certain locations resulting in hole-rich superconducting domains. Granular superconductivity arising from tunnelling between such domains would represent a new view of the underdoped copper oxide superconductors. Here we report scanning tunnelling microscope studies of underdoped Bi2Sr2CaCu2O8+delta that reveal an apparent segregation of the electronic structure into superconducting domains that are approximately 3 nm in size (and local energy gap <50 meV), located in an electronically distinct background. We used scattering resonances at Ni impurity atoms as 'markers' for local superconductivity; no Ni resonances were detected in any region where the local energy gap Delta > 50 +/- 2.5 meV. These observations suggest that underdoped Bi2Sr2CaCu2O8+delta is a mixture of two different short-range electronic orders with the long-range characteristics of a granular superconductor.

A four unit cell periodic pattern of quasi-particle states surrounding vortex cores in Bi2Sr2CaCu2O8+delta

Scanning tunneling microscopy is used to image the additional quasi-particle states generated by quantized vortices in the high critical temperature superconductor Bi2Sr2CaCu2O8+delta. They exhibit a copper-oxygen bond-oriented "checkerboard" pattern, with four unit cell (4a0) periodicity and a approximately 30 angstrom decay length. These electronic modulations may be related to the magnetic field-induced, 8a0 periodic, spin density modulations with decay length of approximately 70 angstroms recently discovered in La1.84Sr0.16CuO4. The proposed explanation is a spin density wave localized surrounding each vortex core. General theoretical principles predict that, in the cuprates, a localized spin modulation of wavelength lambda should be associated with a corresponding electronic modulation of wavelength lambda/2, in good agreement with our observations.

Chondrocyte death precedes structural damage in blunt impact trauma

Joint impact trauma has been shown to cause fissures, fibrillation, and other structural damage of the cartilage or subchondral bone. Previous studies used impact energies sufficient to fracture the underlying bone. Under these circumstances, the initial influence of impact trauma on cellular components and cartilage structure is unknown. The goal of this study was to determine whether an impact trauma first causes cellular or structural damage to a cartilage layer. Such damage might be the starting point of degenerative changes found in osteoarthrosis. Porcine patellas (n = 12) were subjected to standardized low-impact loading of three magnitudes with a spherical impactor attached to a drop tower device (0.06, 0.1, and 0.2 J). India ink staining and scanning electron microscopic analysis were used for analysis and showed no evidence of gross structural disruption. Chondrocyte viability assessed with thiazole blue staining and propidium iodide counterstaining was reduced significantly in the tangential and middle zones with increasing impact energy. These results indicate that chondrocyte death may precede excessive structural damage reported in earlier studies and might be a crucial factor in posttraumatic osteoarthrosis.

The role of visual attention in saccadic eye movements

The relationship between saccadic eye movements and covert orienting or visual spatial attention was investigated in two experiments. In the first experiment, subjects were required to make a saccade to a specified location while also detecting a visual target presented just prior to the eye movement. Detection accuracy was highest when the location of the target coincided with the location of the saccade, suggesting that subjects use spatial attention in the programming and/or execution of saccadic eye movements. In the second experiment, subjects were explicitly directed to attend to a particular location and to make a saccade to the same location or to a different one. Superior target detection occurred at the saccade location regardless of attention instructions. This finding shows that subjects cannot move their eyes to one location and attend to a different one. The result of these experiments suggest that visuospatial attention is an important mechanism in generating voluntary saccadic eye movements.

Recognition memory and attentional selection: serial scanning is not enough

In two experiments, using memory sets of up to 10 letters, the response competition paradigm was employed to investigate the extent to which extraneous visual stimuli interfere with or affect the process of memory search. It was assumed that if selective attention could exclude the effect of noise letters from a Sternberg-type memory comparison process, then there would be an increase in intercept for the reaction time-set size functions but no increase in slope. This result was obtained. However, a large difference in response times to both positive and negative set targets was found when the accompanying noise letters indicated a competing response, as opposed to when they indicated the same response as the target. This implies rapid identification of the nature of both target and noise, independent of a serial comparison process. A modification of a dual process model (Juola, Fischler, Wood, & Atkinson, 1971) in which stimuli activate a familiarity value independent of memory search was suggested to account for these results.

Hyperpyrexia associated with intravenous cimetidine therapy. Report of a case

Fever as a drug reaction is common. It has, however, not been widely recognized as a complication of cimetidine therapy. We observed a patient who, during the administration of intravenous cimetidine, became hyperpyretic and confused. Six hours after cimetidine therapy was discontinued, he became afebrile. The potential for hyperpyrexia to occur with cimetidine should be considered in patients with unexplained fever who are receiving this drug.

Conjunction of color and form without attention: evidence from an orientation-contingent color aftereffect

According to feature-integration theory (Treisman & Gelade, 1980), separable features such as color and shape exist in separate maps in preattentive vision and can be integrated only through the use of spatial attention. Many perceptual aftereffects, however, which are also assumed to reflect the features available in preattentive vision, are sensitive to conjunctions of features. One possible resolution of these views holds that adaptation to conjunctions depends on spatial attention. We tested this proposition by presenting observers with gratings varying in color and orientation. The resulting McCollough aftereffects were independent of whether the adaptation stimuli were presented inside or outside of the focus of spatial attention. Therefore, color and shape appear to be conjoined preattentively, when perceptual aftereffects are used as the measure. These same stimuli, however, appeared to be separable in two additional experiments that required observers to search for gratings of a specified color and orientation. These results show that different experimental procedures may be tapping into different stages of preattentive vision.

Recognition memory and attentional selection: Serial scanning is not enough

In two experiments, using memory sets of up to 10 letters, the response competition paradigm was employed to investigate the extent to which extraneous visual stimuli interfere with or affect the process of memory search. It was assumed that if selective attention could exclude the effect of noise letters from a Sternberg-type memory comparison process, then there would be an increase in intercept for the reaction time-set size functions but no increase in slope. This result was obtained. However, a large difference in response times to both positive and negative set targets was found when the accompanying noise letters indicated a competing response, as opposed to when they indicated the same response as the target. This implies rapid identification of the nature of both target and noise, independent of a serial comparison process. A modification of a dual process model (Juola, Fischler, Wood, & Atkinson, 1971) in which stimuli activate a familiarity value independent of memory search was suggested to account for these results.

Conjunction of color and form without attention: Evidence from an orientation-contingent color aftereffect

According to feature-integration theory (Treisman & Gelade, 1980), separable features such as color and shape exist in separate maps in preattentive vision and can be integrated only through the use of spatial attention. Many perceptual aftereffects, however, which are also assumed to reflect the features available in preattentive vision, are sensitive to conjunctions of features. One possible resolution of these views holds that adaptation to conjunctions depends on spatial attention. We tested this proposition by presenting observers with gratings varying in color and orientation. The resulting McCollough aftereffects were independent of whether the adaptation stimuli were presented inside or outside of the focus of spatial attention. Therefore, color and shape appear to be conjoined preattentively, when perceptual aftereffects are used as the measure. These same stimuli, however, appeared to be separable in two additional experiments that required observers to search for gratings of a specified color and orientation. These results show that different experimental procedures may be tapping into different stages of preattentive vision.

Event-related potentials elicited by automatic targets: a dual-task analysis

The role of limited capacity processes in the detection of automatic targets was investigated in a dual-task paradigm using both behavioral and event-related brain potential (ERP) measures. An automatic detection task was paired with another concurrent discrimination while the relative importance of each task was systematically varied. The resulting performance operating characteristic (POC) showed that both the speed and accuracy of automatic detection responses were affected by the allocation of attention. Reductions in the accuracy of each task were accompanied by reductions in the amplitude of a late-positive component of the ERP (P300). In addition, the latency of the P300 component elicited by automatic targets was increased in dual-task conditions. A comparison of behavioral and ERP measures suggested the involvement of two separate limited-capacity processes in automatic detection: one concerned with the formation of an episodic representation of target occurrence and the other with the execution of rapid motor responses.

Event-related potentials elicited by automatic targets: A dual-task analysis

The role of limited capacity processes in the detection of automatic targets was investigated in a dual-task paradigm using both behavioral and event-related brain potential (ERP) measures. An automatic detection task was paired with another concurrent discrimination while the relative importance of each task was systematically varied. The resulting performance operating characteristic (POC) showed that both the speed and accuracy of automatic detection responses were affected by the allocation of attention. Reductions in the accuracy of each task were accompanied by reductions in the amplitude of a late-positive component of the ERP (P300). In addition, the latency of the P300 component elicited by automatic targets was increased in dual-task conditions. A comparison of behavioral and ERP measures suggested the involvement of two separate limited-capacity processes in automatic detection: one concerned with the formation of an episodic representation of target occurrence and the other with the execution of rapid motor responses.

The component structure of event-related slow potentials: task, ISI, and warning stimulus effects on the 'E' wave

Two experiments were conducted to investigate the role of task variables and ISI length on the late component of the event-related slow potential (ERSP) recorded during various two-stimulus anticipation tasks. In the first experiment, a two-component ERSP was observed during short (1 sec) and long (4 sec) ISI conditions. The first component was generally Fz dominant and independent of task variables. The second component was generally Cz dominant and most prominent when an immediate motor response was required. A second experiment was successful in eliciting large second ERSP components even in the absence of response requirements. In this experiment, the topography of the second component was not exclusively Cz dominant; rather, it was task dependent, and achieved Fz dominance under delayed-response conditions. Heart rate, monitored concurrently with the EEG, also reflected the change in experimental conditions by the enhancement of a mid-ISI acceleratory component. The data are discussed with respect to a multiple-component model of slow potential activity during periods in which subjects anticipate significant events.

Interaction between global and local levels of a form

Two experiments investigated a model for global procedence, which states that global aspects of a form are invariably recognized prior to local levels. Experiment 1 showed that speed of recognition was approximately the same for global and local levels of a form. Experiment 2 independently manipulated the "quality" of information at global and local levels by distorting the forms. Either local or global precedence could be obtained depending on which level was distorted. These results suggest that the specific interaction between local and global levels will depend on the relative visibility or quality of form information at each level.

Lack of glucagon response to hypoglycemia in diabetic autonomic neuropathy

Glucagon response to insulin hypoglycemia was tested in diabetics with autonomic neuropathy (N=9), diabetics without neuropathy (N=8), and normals (N=9). With similar levels of hypoglycemia, growth hormone and plasma cortisol increased in all groups. The glucagon response in normals (121+/-19 vs. 308+/-30 pg./ml., mean+/-S.E.M. of baseline vs. hypoglycemia peak) was significantly less in nonneuropathic diabetics than in normals (128+/-13 vs. 209+/-30) and absent in neuropathic diabetes (128+/-23 vs. 115+/-20). Arginine stimulation produced a glucagon response in the neuropathic diabetics (106+/-16 vs. 523+/-103). The data indicate that the capacity to release glucagon during hypoglycemia is lost in diabetic neuropathy while glucagon responsiveness to arginine is retained. Neuropathy in diabetes may contribute to metabolic instability.

Multiple gastric polyps and parathyroid adenomas. Report of two cases

Two cases of multiple gastric polyps associated with parathyroid adenomas are presented. A review of the literature revealed four patients with multiple gastric polyps and multiple endocrine adenomatosis. The possiblity of multiple gastric polyps as a variant of the MEA syndrome complex is explored. Emphasis is placed on the need for thorough endocrine evaluation in patients with multiple gastric polyps.