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We present a deep learning approximation, stochastic optimization based, method for wave kinetic equations. To build confidence in our approach, we apply the method to a Smoluchowski coagulation equation with multiplicative kernel for which an analytic solution exists. Our deep learning approach is then used to approximate the non-stationary solution to a 3-wave kinetic equation corresponding to acoustic wave systems. To validate the neural network approximation, we compare the decay rate of the total energy with previously obtained theoretical results. A finite volume solution is presented and compared with the present method.

We introduce a finite volume scheme to solve a special case of isotropic 3-wave kinetic equations. We test our numerical solution against theoretical results concerning the long time behavior of the energy and observe that our solutions verify the energy cascade phenomenon. To our knowledge, this is the first numerical scheme that can capture the long time asymptotic behavior of solutions to those isotropic 3-wave kinetic equations, where the energy cascade can be observed. Our numerical energy cascade rates are in good agreement with previously obtained theoretical results. The finite volume scheme given here relies on a new identity, allowing one to reduce the number of terms needed in the collision operators.

One of the primary challenges facing scientists is extracting understanding from the large amounts of data produced by simulations, experiments, and observational facilities. The use of data across the entire lifetime ranging from real-time to post-hoc analysis is complex and varied, typically requiring a collaborative effort across multiple teams of scientists. Over time, three sets of tools have emerged: one set for analysis, another for visualization, and a final set for orchestrating the tasks. This trifurcated tool set often results in the manual assembly of analysis and visualization workflows, which are one-off solutions that are often fragile and difficult to generalize. To address these challenges, we propose a serviced-based paradigm and a set of abstractions to guide its design. These abstractions allow for the creation of services that can access and interpret data, and enable interoperability for intelligent scheduling of workflow systems. This work results from a codesign process over analysis, visualization, and workflow tools to provide the flexibility required for production use. Finally, this paper describes a forward-looking research and development plan that centers on the concept of visualization and analysis technology as reusable services, and also describes several real-world use cases that implement these concepts.

The rehabilitation of post-prostatectomy urinary incontinence has traditionally focused on pelvic floor strengthening exercise. The goal of this study was to determine whether an individualized pelvic physical therapy (PT) program aimed at normalizing both underactive and overactive pelvic floor dysfunction (PFD) can result in improvement in post-prostatectomy stress urinary incontinence (SUI) and pelvic pain. A retrospective chart review of 136 patients with post-prostatectomy SUI and treated with pelvic PT. Patients were identified as having either underactive, overactive, or mixed-type PFD and treated accordingly with a tailored program to normalize pelvic floor function. Outcomes including decrease in SUI as measured in pad usage per day and pain rated on the numeric pain rating scale. Twenty five patients were found to have underactive PFD and were treated with strengthening. Thirteen patients had overactive PFD and were treated with relaxation training. Ninety eight patients had mixed-type PFD and were treated with a combination of relaxation training followed by strengthening. Patients demonstrated statistically significant decrease in pad usage per day (p

Fibrinopeptide A (FPA) levels which have been shown to be a quantitative index of thrombin generation, were measured in blood and cerebrospinal fluid (CSF) samples from patients following subarachnoid haemorrhage (SAH) and from a control population. The levels found in samples obtained in patients following SAH are compared with those found in controls and also correlated with clinical grade on admission as assessed by the Glasgow Coma Score and the World Federation of Neurological Surgeons' grading system, and with the amount of subarachnoid blood seen on CT, the occurrence of ischaemic deterioration, the occurrence of low-density change on CT, the presence of vasospasm on angiography, clinical outcome as assessed by the Glasgow Outcome Score 3 months following the ictus, and the incidence of ischaemia as a cause of death or disability as assessed 3 months following the ictus. The levels of FPA found in blood and CSF from patients following SAH were significantly raised when compared with those found in controls. There was significant correlation between blood FPA levels and the amount of subarachnoid blood seen on initial CT. CSF FPA levels had a statistically significant correlation with outcome as assessed at 3 months post-ictus. No statistically significant correlation was found between blood or CSF FPA levels and any of the other variables studied.

Positron emission tomography (PET) studies of the heart focus on evaluation of myocardial blood flow and metabolism.1 These measurements must frequently be correlated with changes in left ventricular (LV) contraction to delineate myocardial viability fully.2 Usually, this requires assessment of myocardial contraction using a different imaging modality; however, this information may be obtained at a different time and in different planes from the PET studies. In segments displaying impaired contraction, the preservation of glucose metabolism is a marker of jeopardised but viable myocardium in patients with coronary artery disease. We describe a pilot study using ECG gated PET with18F-flourodeoxyglucose (FDG) to detect segments with reduced wall thickening. Wall thickening is compared to ECG gated cine-magnetic resonance imaging (MRI). MRI is well validated for the assessment of myocardial motion and thickening in patients with normal and impaired LV contraction.3 The study population comprised nine patients (all men) with ischaemic heart disease and LV impairment, from angiography. Their mean age was 62 years (range 42–75 years). Cine-MR images were obtained in the short axis, positioned using the end systolic long axis view as the frame of reference. Acquisitions were synchronised to the ECG, using the R wave as a trigger. Seven cardiac phases were obtained with a frame separation of 80 ms. …

Prostaglandin E2, thromboxane B2, and 6-oxo-prostaglandin F1 alpha were assayed in blood and cerebrospinal fluid samples from patients after subarachnoid hemorrhage (SAH) and from a control population. The levels found in samples obtained from patients after SAH were compared with those found in controls and were also correlated with a number of clinical and radiological variables, many of which are either significantly associated with or represent evidence of cerebral ischemia. The levels of prostaglandin E2, thromboxane B2, and 6-oxo-prostaglandin F1 alpha in blood samples from patients after SAH and from controls were below the level of sensitivity of the assays. Levels of prostaglandin E2, thromboxane B2, and 6-oxo-prostaglandin F1 alpha in cerebrospinal fluid from patients after SAH were significantly elevated when compared with those found in control samples. There was no significant correlation, however, between the level of each prostaglandin measured and the following variables: clinical grade on admission as assessed by the Glasgow Coma Score and the World Federation of Neurological Surgeons grading system; the amount of subarachnoid blood seen on computed tomographic scan; the occurrence of ischemic deterioration; the occurrence of low density change on computed tomographic scan; the presence of vasospasm on angiography; clinical outcome as assessed by the Glasgow Coma Score 3 months after the ictus; and the incidence of ischemia as a cause of death or disability as assessed 3 months after the ictus. A primary role for prostaglandins in the etiology of delayed cerebral ischemia after SAH is not therefore confirmed.

Kinneavy's theory of discourse and Mathes' concept of contextual editing can be effectively applied to teaching classification in technical writing. My procedure, in the nine steps described here, provides students with an understanding of classification as an analytical and generative tool. Its usefulness in analysis is discovered through a structural study of Mumford's “Machines, Utilities, and ‘The Machine‘”; an awareness of Mumford's classificatory structure helps students understand his essay. Students see for themselves, by organizing facts into paragraphs, the generative power of contextual editing applied to classification; the same kind of structuring Mumford uses can be used in their own writing. This generative application simulates the research-to-writing process and dramatically increases the coherence and clarity of much student writing.