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关键词： Outcome-wide epidemiology   Domains of life satisfaction   Older adults   Public health  

摘要： Purpose Growing evidence documents strong associations between overall life satisfaction and favorable health and well-being outcomes. However, because most previous studies have assessed satisfaction with one's life as a whole, we know little about whether specific domains of life satisfaction (e.g., satisfaction with family life, income) might be responsible for longitudinally driving better health and well-being. Methods Data were from 13,752 participants in the Health and Retirement Study-a prospective and nationally representative cohort of US adults aged > 50. We evaluated if positive changes in seven individual domains of life satisfaction (between t(0);2008/2010 and t(1);2012/2014) were associated with 35 indicators of physical, behavioral, and psychosocial health and well-being (at t(2);2016/2018). Results Most domains of life satisfaction were associated with psychological outcomes: satisfaction with family and non-work activities showed the largest associations (sometimes double in magnitude) with subsequent psychological factors, followed by satisfaction with financial situation and income. Further, some domains showed associations with specific physical health outcomes (e.g., mortality, number of chronic conditions, physical functioning limitations), health behaviors (e.g., sleep problems), and social factors (e.g., loneliness). Conclusions As countries seek innovative and cost-effective methods of enhancing the health and well-being of our rapidly aging populations, findings from our study suggest that some domains of life satisfaction have a substantially larger influence on health and well-being outcomes than others. Individual domains of life satisfaction might be novel targets for interventions and policies seeking to enhance specific facets of health and well-being.

关键词： Singular perturbation problems   Boundary layers   Nonlinear differential equations   Finite difference scheme   Shishkin mesh   Parameter-uniform convergence   Two-time scale systems  

摘要： In this article, a nonlinear system of singularly perturbed differential equations arising in a two-time scale system is considered. A computational method consists of the standard backward difference operator and a piecewise uniform Shishkin mesh is constructed to solve the system. The computational method is proved to be first order convergent uniformly with respect to the perturbation parameter. Numerical experiments support the theoretical results.

关键词： Household epidemic model   McKean-Vlasov equations   interacting Markov jump processes  

摘要： This paper presents a new view of household epidemic models, where we exploit the fact that the interaction between the households is of mean field type. We prove the convergence, as the number of households tends to infinity, of the number of infectious individuals in a uniformly chosen household to a nonlinear Markov process solving a McKean-Vlasov Poisson driven stochastic differential equation, as well as a propagation of chaos result. We also define a basic reproduction number R-* and show that if R-* > 1, then the nonlinear Markov process has a unique nontrivial ergodic invariant probability measure, whereas if R-* <= 1, it converges to 0 as t tends to infinity.

关键词： Singularly perturbed differential equations   Boundary value problems   Parameter uniform methods   Grid equidistribution   Robust discretization   Hybrid difference scheme  

摘要： The paper presents a higher-order parameter uniform numerical approximation of a fourth-order singularly perturbed boundary value problem on a non-uniform grid. The given problem is converted into a coupled system of singularly perturbed differential equations. The coupled system of equation is discretized on a non-uniform mesh using a higher-order hybrid difference scheme. The grid equidistribution principle, based on a positive monitor function, is used to formulate the grid. The properties of the discrete operator are utilized on the equidistributed grid to obtain fourth-order parameter uniform convergence. The convergence obtained is optimal in the sense that it is free from any logarithmic term. Numerical result for two model problems is presented, which agree with the theoretical estimates.

关键词： Thyroid cancer   Lymph nodes   Neck dissection   Neuroma  

摘要： Objectives Traumatic neuromas (TNs) mimic recurrent tumors in US after total thyroidectomy (TT) and lateral neck dissection (LND) for thyroid cancer. We aimed to evaluate whether CT could complement US in the differential diagnosis of TNs from recurrent thyroid cancer in the dissected neck. Material and methods We retrospectively included a total of 97 consecutive US-detected lesions (28 TNs and 69 recurrent tumors) in patients with a previous history of TT and LND for thyroid cancer. The lesions were classified as benign, indeterminate, or suspicious according to the presence of benign or suspicious features on US and CT. Imaging features and categories on US and CT were compared between TNs and recurrent tumors. The diagnostic performances of US and CT for differentiating between TNs and recurrent tumors were calculated. Results On US, most TNs and recurrent tumors showed internal hyperechogenicity without hilar echogenicity or hilar vascularity and were categorized as suspicious lesions (23/28, 82.1% vs. 53/69, 76.8%). On CT, all TNs lacked strong enhancement without hilar fat or hilar vessel enhancement and were categorized as indeterminate lesions (28/28, 100%). In contrast, most recurrent tumors showed strong enhancement and were categorized as suspicious lesions (63/69, 91.3%). The addition of CT to US corrected 23 false-positive diagnoses in 28 TNs and 10 false-negative diagnoses in 69 recurrent tumors. Conclusions CT complements US for the correct differentiation of TNs from recurrent tumors in postoperative thyroid cancer patients. The addition of CT to US may prevent unnecessary painful biopsy or surgery.

关键词： Abusive head injury   AHT   Benign external hydrocephalus   Child abuse   SBS   Shaken baby syndrome   Subdural haematoma   subdural hygroma  

摘要： Background Criteria for diagnosing abusive head trauma (AHT) or "shaken baby syndrome" are not well defined;consequently, these conditions might be diagnosed on failing premises. Methods The authors have collected a total of 28 infants, from the US (20) and Norway (8), suspected of having been violently shaken, and their caregivers had been suspected, investigated, prosecuted or convicted of having performed this action. Among 26 symptomatic infants, there were 18 boys (69%) and 8 girls (31%)-mean age 5.1 month, without age difference between genders. Results Twenty-one of 26 symptomatic children (81%) had a head circumference at or above the 90 percentile, and 18 had a head circumference at or above the 97 percentile. After macrocephaly, seizure was the most frequent initial symptom in 13 (50%) of the symptomatic infants. Seventeen (65%) of the symptomatic infants had bilateral retinal haemorrhages, and two had unilateral retinal haemorrhages. All infants had neuroimaging compatible with chronic subdural haematomas/hygromas as well as radiological characteristics compatible with benign external hydrocephalus (BEH). Conclusions BEH with subdural haematomas/hygromas in infants may sometimes be misdiagnosed as abusive head trauma. Based on the authors' experience and findings of the study, the following measures are suggested to avoid this diagnostic pitfall: medical experts in infant abuse cases should be trained in recognising clinical and radiological BEH features, clinicians with neuro-paediatric experience should always be included in the expert teams and reliable information about the head circumference development from birth should always be available.

关键词： Voltage   Capacitors   Maximum power point trackers   Wires   Voltage control   Scalability   Hardware   Differential power processing (DPP)   maximum power point   plug and play   solar energy   modular  

摘要： This article proposes a realization of the photovoltaic (PV) panel to PV panel (P2P) method for the modular differential power processing (mDPP). The approach is modular and permits panels to be added to or removed from either series strings or paralleled connections. A voltage inner loop and power outer loop control strategy tracks the individual maximum power point of the PV panel, as well as converts only the differential power. The proposed method decouples the control loop performance of each PV module, making design simple. Simulation results validate the plug and play function for scalable PV system and MPPT accuracy. Hardware prototype is also built, and both indoor and outdoor experiments are provided to exhibit the advantage of this P2P method. Drawbacks and limitations are also discussed.

关键词： Gastrointestinal stromal tumors   Sarcoma   Machine learning   Tomography   X-ray computed   Radiomics  

摘要： Treatment planning of gastrointestinal stromal tumors (GISTs) includes distinguishing GISTs from other intra-abdominal tumors and GISTs' molecular analysis. The aim of this study was to evaluate radiomics for distinguishing GISTs from other intra-abdominal tumors, and in GISTs, predict the c-KIT, PDGFRA, BRAF mutational status, and mitotic index (MI). Patients diagnosed at the Erasmus MC between 2004 and 2017, with GIST or non-GIST intra-abdominal tumors and a contrast-enhanced venous-phase CT, were retrospectively included. Tumors were segmented, from which 564 image features were extracted. Prediction models were constructed using a combination of machine learning approaches. The evaluation was performed in a 100 x random-split cross-validation. Model performance was compared to that of three radiologists. One hundred twenty-five GISTs and 122 non-GISTs were included. The GIST vs. non-GIST radiomics model had a mean area under the curve (AUC) of 0.77. Three radiologists had an AUC of 0.69, 0.76, and 0.84, respectively. The radiomics model had an AUC of 0.52 for c-KIT, 0.56 for c-KIT exon 11, and 0.52 for the MI. The numbers of PDGFRA, BRAF, and other c-KIT mutations were too low for analysis. Our radiomics model was able to distinguish GISTs from non-GISTs with a performance similar to three radiologists, but less observer dependent. Therefore, it may aid in the early diagnosis of GIST, facilitating rapid referral to specialized treatment centers. As the model was not able to predict any genetic or molecular features, it cannot aid in treatment planning yet.