Stability and asymptotic behavior of periodic traveling wave solutions of viscous conservation laws in several dimensions

Under natural spectral stability assumptions motivated by previous investigations of the associated spectral stability problem, we determine sharp $L^p$ estimates on the linearized solution operator about a multidimensional planar periodic wave of a system of conservation laws with viscosity, yielding linearized $L^1\cap L^p\to L^p$ stability for all $p \ge 2$ and dimensions $d \ge 1$ and nonlinear $L^1\cap H^s\to L^p\cap H^s$ stability and $L^2$-asymptotic behavior for $p\ge 2$ and $d\ge 3$. The behavior can in general be rather complicated, involving both convective (i.e., wave-like) and diffusive effects

Health coaching to encourage obese adults to enroll in commercially-available weight management programs: The path to health study

Physicians are recommended to screen and refer obese patients to weight management programs (WMPs). There are often limited referral options for physicians, though commercially-available WMPs could be a potential solution. The purpose of this study (Path to Health) was to evaluate the efficacy of health coaching to promote enrollment in commercially-available WMPs through a two-arm, RCT with obese patients (n = 168) randomly assigned to intervention (n = 84) or control groups (n = 84). Intervention participants received phone health coaching to help them select and enroll in WMPs. We collected data on program enrollment, weight, self-reported physical activity (PA), and fruit and vegetable (FV) intake at baseline, 3- and 6-months. We used logistic regression to assess the intervention effect on enrollment in WMPs and longitudinal regression models to evaluate the effect on weight change, PA and FV intake. The average age was 54.7 years, 59% were female and 43% were Black and 49% were White. At 6 months, 39% of the intervention group (vs. 29% of control) had enrolled in WMPs. We found no longitudinal intervention effect on weight, PA and FV intake. We found that there was more weight loss for those who completed ≥4 calls as compared to those who completedstudy, we found that phone health coaching was successful in increasing obese adults\u27 enrollment in commercially-available WMPs and that there was a dose response relationship for weight and behavioral outcomes

Screening for obstructive sleep apnea on the internet: randomized trial.

BACKGROUND: Obstructive sleep apnea is underdiagnosed. We conducted a pilot randomized controlled trial of an online intervention to promote obstructive sleep apnea screening among members of an Internet weight-loss community. METHODS: Members of an Internet weight-loss community who have never been diagnosed with obstructive sleep apnea or discussed the condition with their healthcare provider were randomized to intervention (online risk assessment+feedback) or control. The primary outcome was discussing obstructive sleep apnea with a healthcare provider at 12 weeks. RESULTS: Of 4700 members who were sent e-mail study announcements, 168 (97% were female, age 39.5 years [standard deviation 11.7], body mass index 30.3 [standard deviation 7.8]) were randomized to intervention (n=84) or control (n=84). Of 82 intervention subjects who completed the risk assessment, 50 (61%) were low risk and 32 (39%) were high risk for obstructive sleep apnea. Intervention subjects were more likely than control subjects to discuss obstructive sleep apnea with their healthcare provider within 12 weeks (11% [9/84] vs 2% [2/84]; P=.02; relative risk=4.50; 95% confidence interval, 1.002-20.21). The number needed to treat was 12. High-risk intervention subjects were more likely than control subjects to discuss obstructive sleep apnea with their healthcare provider (19% [6/32] vs 2% [2/84]; P=.004; relative risk=7.88; 95% confidence interval, 1.68-37.02). One high-risk intervention subject started treatment for obstructive sleep apnea. CONCLUSION: An online screening intervention is feasible and likely effective in encouraging members of an Internet weight-loss community to discuss obstructive sleep apnea with their healthcare provider

Feasibility and potential efficacy of commercial mHealth/eHealth tools for weight loss in African American breast cancer survivors: pilot randomized controlled trial

Weight management after breast cancer (BC) treatment in African American (AA) women is crucial to reduce comorbid conditions and health disparities. We examined feasibility and potential efficacy of commercial eHealth/mHealth tools for weight management in AA BC survivors in New Jersey. Participants (N = 35) were randomized to an intervention (SparkPeople) plus activity tracker, Fitbit Charge (n = 18), or wait-list active control group (Fitbit only, n = 17). Anthropometric, behavioral, and quality of life (QOL) outcomes were collected at baseline, 3, 6, and 12 months. Differences in outcomes were assessed using intent-to-treat analysis. Retention was 97.1%. Both groups lost weight, with no significant differences between groups. At month 6, mean weight change was: intervention: -1.71 kg (SD 2.33; p = .006), 33.3% lost ≥3% of baseline weight; control: -2.54 kg (SD 4.00, p = .002), 23.5% lost ≥3% weight. Intervention participants achieved significant improvements in waist circumference (-3.56 cm, SD 4.70, p = .005), QOL (p = .030), and use of strategies for healthy eating (p = .025) and decreasing calories (p \u3c .001). Number of days logged food per week was associated with decreases in waist circumference at 6 months (β -0.79, 95% CI, -1.49, -0.09, p = .030) and 12 months (β -2.16, 95% CI, -4.17, -0.15, p = .038). Weight loss was maintained at 12 months. This is the first study to demonstrate potential efficacy of commercial eHealth/mHealth tools for weight loss in AA BC survivors, without additional counseling from the research team. If effective, they may be convenient weight loss tools that can be easily and widely disseminated. Clinical Trials registration: ClinicalTrials.gov NCT02699983

Primary care providers\u27 perspectives on online weight-loss programs: a big wish list

BACKGROUND: Integrating online weight-loss programs into the primary care setting could yield substantial public health benefit. Little is known about primary care providers\u27 perspectives on online weight-loss programs. OBJECTIVE: To assess primary care providers\u27 perspectives on online weight-loss programs. METHODS: We conducted focus group discussions with providers in family medicine, internal medicine, and combined internal medicine/pediatrics in Texas and Pennsylvania, USA. Open-ended questions addressed their experience with and attitudes toward online weight-loss programs; useful characteristics of existing online weight-loss programs; barriers to referring patients to online weight-loss programs; and preferred characteristics of an ideal online weight-loss program. Transcripts were analyzed with the grounded theory approach to identify major themes. RESULTS: A total of 44 primary care providers participated in 9 focus groups. The mean age was 45 (SD 9) years. Providers had limited experience with structured online weight-loss programs and were uncertain about their safety and efficacy. They thought motivated, younger patients would be more likely than others to respond to an online weight-loss program. According to primary care providers, an ideal online weight-loss program would provide-at no cost to the patient-a structured curriculum addressing motivation, psychological issues, and problem solving; tools for tracking diet, exercise, and weight loss; and peer support monitored by experts. Primary care providers were interested in receiving reports about patients from the online weight-loss programs, but were concerned about the time required to review and act on the reports. CONCLUSIONS: Primary care providers have high expectations for how online weight-loss programs should deliver services to patients and fit into the clinical workflow. Efforts to integrate online weight-loss programs into the primary care setting should address efficacy and safety of online weight-loss programs in clinic-based populations; acceptable methods of sending reports to primary care providers about their patients\u27 progress; and elimination or reduction of costs to patients

Automatic Hip Fracture Identification and Functional Subclassification with Deep Learning

Purpose: Hip fractures are a common cause of morbidity and mortality. Automatic identification and classification of hip fractures using deep learning may improve outcomes by reducing diagnostic errors and decreasing time to operation. Methods: Hip and pelvic radiographs from 1118 studies were reviewed and 3034 hips were labeled via bounding boxes and classified as normal, displaced femoral neck fracture, nondisplaced femoral neck fracture, intertrochanteric fracture, previous ORIF, or previous arthroplasty. A deep learning-based object detection model was trained to automate the placement of the bounding boxes. A Densely Connected Convolutional Neural Network (DenseNet) was trained on a subset of the bounding box images, and its performance evaluated on a held out test set and by comparison on a 100-image subset to two groups of human observers: fellowship-trained radiologists and orthopaedists, and senior residents in emergency medicine, radiology, and orthopaedics. Results: The binary accuracy for fracture of our model was 93.8% (95% CI, 91.3-95.8%), with sensitivity of 92.7% (95% CI, 88.7-95.6%), and specificity 95.0% (95% CI, 91.5-97.3%). Multiclass classification accuracy was 90.4% (95% CI, 87.4-92.9%). When compared to human observers, our model achieved at least expert-level classification under all conditions. Additionally, when the model was used as an aid, human performance improved, with aided resident performance approximating unaided fellowship-trained expert performance. Conclusions: Our deep learning model identified and classified hip fractures with at least expert-level accuracy, and when used as an aid improved human performance, with aided resident performance approximating that of unaided fellowship-trained attendings.Comment: Presented at Orthopaedic Research Society, Austin, TX, Feb 2, 2019, currently in submission for publicatio

Intracranial microcapsule chemotherapy delivery for the localized treatment of rodent metastatic breast adenocarcinoma in the brain

Metastases represent the most common brain tumors in adults. Surgical resection alone results in 45% recurrence and is usually accompanied by radiation and chemotherapy. Adequate chemotherapy delivery to the CNS is hindered by the blood–brain barrier. Efforts at delivering chemotherapy locally to gliomas have shown modest increases in survival, likely limited by the infiltrative nature of the tumor. Temozolomide (TMZ) is first-line treatment for gliomas and recurrent brain metastases. Doxorubicin (DOX) is used in treating many types of breast cancer, although its use is limited by severe cardiac toxicity. Intracranially implanted DOX and TMZ microcapsules are compared with systemic administration of the same treatments in a rodent model of breast adenocarcinoma brain metastases. Outcomes were animal survival, quantified drug exposure, and distribution of cleaved caspase 3. Intracranial delivery of TMZ and systemic DOX administration prolong survival more than intracranial DOX or systemic TMZ. Intracranial TMZ generates the more robust induction of apoptotic pathways. We postulate that these differences may be explained by distribution profiles of each drug when administered intracranially: TMZ displays a broader distribution profile than DOX. These microcapsule devices provide a safe, reliable vehicle for intracranial chemotherapy delivery and have the capacity to be efficacious and superior to systemic delivery of chemotherapy. Future work should include strategies to improve the distribution profile. These findings also have broader implications in localized drug delivery to all tissue, because the efficacy of a drug will always be limited by its ability to diffuse into surrounding tissue past its delivery source.National Institutes of Health (U.S.) (Grant R01 EB006365-06)Brain Science Foundation (Private Grant 106708

Single-Mode Squeezed Light Generation and Tomography with an Integrated Optical Parametric Oscillator

Quantum optical technologies promise advances in sensing, computing, and communication. A key resource is squeezed light, where quantum noise is redistributed between optical quadratures. We introduce a monolithic, chip-scale platform that exploits the $\chi^{(2)}$ nonlinearity of a thin-film lithium niobate (TFLN) resonator device to efficiently generate squeezed states of light. Our system integrates all essential components -- except for the laser and two detectors -- on a single chip with an area of one square centimeter, significantly reducing the size, operational complexity, and power consumption associated with conventional setups. Our work addresses challenges that have limited previous integrated nonlinear photonic implementations that rely on either $\chi^{(3)}$ nonlinear resonators or on integrated waveguide $\chi^{(2)}$ parametric amplifiers. Using the balanced homodyne measurement subsystem that we implemented on the same chip, we measure a squeezing of 0.55 dB and an anti-squeezing of 1.55 dB. We use 20 mW of input power to generate the parametric oscillator pump field by employing second harmonic generation on the same chip. Our work represents a substantial step toward compact and efficient quantum optical systems posed to leverage the rapid advances in integrated nonlinear and quantum photonics.Comment: 21 pages; 4 figures in main body, 8 supplementary figure