Comorbid Conditions in Idiopathic Pulmonary Fibrosis: Recognition and Management.

Idiopathic pulmonary fibrosis (IPF), a fibrosing interstitial pneumonia of unknown etiology, primarily affects older adults and leads to a progressive decline in lung function and quality of life. With a median survival of 3-5 years, IPF is the most common and deadly of the idiopathic interstitial pneumonias. Despite the poor survivorship, there exists substantial variation in disease progression, making accurate prognostication difficult. Lung transplantation remains the sole curative intervention in IPF, but two anti-fibrotic therapies were recently shown to slow pulmonary function decline and are now approved for the treatment of IPF in many countries around the world. While the approval of these therapies represents an important first step in combatting of this devastating disease, a comprehensive approach to diagnosing and treating patients with IPF remains critically important. Included in this comprehensive assessment is the recognition and appropriate management of comorbid conditions. Though IPF is characterized by single organ involvement, many comorbid conditions occur within other organ systems. Common cardiovascular processes include coronary artery disease and pulmonary hypertension (PH), while gastroesophageal reflux and hiatal hernia are the most commonly encountered gastrointestinal disorders. Hematologic abnormalities appear to place patients with IPF at increased risk of venous thromboembolism, while diabetes mellitus (DM) and hypothyroidism are prevalent metabolic disorders. Several pulmonary comorbidities have also been linked to IPF, and include emphysema, lung cancer, and obstructive sleep apnea. While the treatment of some comorbid conditions, such as CAD, DM, and hypothyroidism is recommended irrespective of IPF, the benefit of treating others, such as gastroesophageal reflux and PH, remains unclear. In this review, we highlight common comorbid conditions encountered in IPF, discuss disease-specific diagnostic modalities, and review the current state of treatment data for several key comorbidities

Fractions of Numerical Semigroups

Let S and T be numerical semigroups and let k be a positive integer. We say that S is the quotient of T by k if an integer x belongs to S if and only if kx belongs to T. Given any integer k larger than 1 (resp., larger than 2), every numerical semigroup S is the quotient T/k of infinitely many symmetric (resp., pseudo-symmetric) numerical semigroups T by k. Related examples, probabilistic results, and applications to ring theory are shown. Given an arbitrary positive integer k, it is not true in general that every numerical semigroup S is the quotient of infinitely many numerical semigroups of maximal embedding dimension by k. In fact, a numerical semigroup S is the quotient of infinitely many numerical semigroups of maximal embedding dimension by each positive integer k larger than 1 if and only if S is itself of maximal embedding dimension. Nevertheless, for each numerical semigroup S, for all sufficiently large positive integers k, S is the quotient of a numerical semigroup of maximal embedding dimension by k. Related results and examples are also given

Transfer Pricing Equity: An Examination of Reported Revenue versus Expected Revenue

This research examines whether African crude oil and natural gas liquids (NGLs) sales revenue deviates from expected sales revenue based on market prices. The deviation may be the result of International Oil Companies (IOCs) transferring a significant amount of crude oils and NGLs to other regions of the world to be turned into finished goods, due to the lack of refining capacity in Africa. This situation suggests that the African region’s governments are placed at a significant disadvantage from profiting off the crude oils and NGLs reserves in their countries because they cannot turn the majority of crude oils and NGLs into finished goods within their country. Thus, IOCs use the accounting concept known as transfer pricing, which allows for goods to be transferred between related enterprises where the integrity of whether the goods were sold at fair market value can be questioned. The use of transfer pricing enables an IOC to shift taxable revenue to different countries where the IOCs operate. IOCs would want to shift revenues from one country to another in an effort to lower their global tax liability. They would accomplish this by shifting revenues from higher tax countries to lower tax countries, and unethical uses of transfer pricing would allow them to achieve this task. This research seeks to determine if revenue is being transferred out of or into Africa during the downstream function of the IOCs’ operations

Differential Equations for Dyson Processes

We call "Dyson process" any process on ensembles of matrices in which the entries undergo diffusion. We are interested in the distribution of the eigenvalues (or singular values) of such matrices. In the original Dyson process it was the ensemble of n by n Hermitian matrices, and the eigenvalues describe n curves. Given sets X_1,...,X_m the probability that for each k no curve passes through X_k at time \tau_k is given by the Fredholm determinant of a certain matrix kernel, the extended Hermite kernel. For this reason we call this Dyson process the Hermite process. Similarly, when the entries of a complex matrix undergo diffusion we call the evolution of its singular values the Laguerre process, for which there is a corresponding extended Laguerre kernel. Scaling the Hermite process at the edge leads to the Airy process and in the bulk to the sine process; scaling the Laguerre process at the edge leads to the Bessel process. Generalizing and strengthening earlier work, we assume that each X_k is a finite union of intervals and find for the Airy process a system of partial differential equations, with the end-points of the intervals of the X_k as independent variables, whose solution determines the probability that for each k no curve passes through X_k at time \tau_k. Then we find the analogous systems for the Hermite process (which is more complicated) and also for the sine process. Finally we find an analogous system of PDEs for the Bessel process, which is the most difficult.Comment: 36 pages, LaTeX. Version 3 corrects an error in the earlier version

A Web Based Water Resources Analysis Portal For Occoquan Watershed

In most of the developed world, water resources data, including both water quality and quantity, has been collected for decades. Such datasets are often used to calibrate water resources models that in turn are capable of producing large amounts of data useful for activities such as forecasting and risk analysis. Like many other domains (e.g., finance, marketing, etc.), significant education, extension, and policy making benefits may be had by building data analytics tools to derive knowledge from these datasets. The knowledge thus available may be turned into intelligence by policy makers and may also be used to enhance environmental education among an area’s stakeholders. Modern information technology infrastructure and development in GIS have eliminated several hindrances that have plagued such endeavors in the past. Using web-GIS based methods we have developed a portal that may be used to visualize and derive knowledge from some of the dataset collected for the Occoquan Reservoir and its tributary watershed in Northern Virginia, USA. The portal is interactive and may be useful for local stakeholders to retrieve near real time data from several sampling stations in the region. At the same time, the design also allows for environmental education of the user. In addition, the portal enables data curation, collects data from several sources in a single database, and provide tools to analyze data irregularities in massive real-time datasets, essential for data managers

Challenges with Internal Photons in Constructive QED

We find the correct spinor amplitude for a simple photon-mediated process and show that, in contrast, the result for the same process using the standard constructive techniques do not agree with Feynman diagrams. Along the way, we analyze the $x$ factor used in photon vertices, we work out the spinor shifts for massive particles when the momenta are analytically continued and we consider the large $z$ limit of the amplitudes in this paper and show that the photon-mediated process does not vanish in this limit for any choice of two of its momenta. For comparison with the photon-mediated process, we also describe two processes with external photons that are mediated by massive particles. In both cases, we show that the current techniques are sufficient and the final results agree with Feynman diagrams. We also demonstrate that by using a massive photon in our calculations and taking the massless limit at the end, we can achieve agreement with Feynman diagrams in all the processes discussed here, including the photon-mediated amplitude.Comment: 43 pages, 0 figure

eTBLAST: a web server to identify expert reviewers, appropriate journals and similar publications

Authors, editors and reviewers alike use the biomedical literature to identify appropriate journals in which to publish, potential reviewers for papers or grants, and collaborators (or competitors) with similar interests. Traditionally, this process has either relied upon personal expertise and knowledge or upon a somewhat unsystematic and laborious process of manually searching through the literature for trends. To help with these tasks, we report three utilities that parse and summarize the results of an abstract similarity search to find appropriate journals for publication, authors with expertise in a given field, and documents similar to a submitted query. The utilities are based upon a program, eTBLAST, designed to identify similar documents within literature databases such as (but not limited to) MEDLINE. These services are freely accessible through the Internet at http://invention.swmed.edu/etblast/etblast.shtml, where users can upload a file or paste text such as an abstract into the browser interface

On Exact Solutions to the Cylindrical Poisson-Boltzmann Equation with Applications to Polyelectrolytes

Using exact results from the theory of completely integrable systems of the Painleve/Toda type, we examine the consequences for the theory of polyelectrolytes in the (nonlinear) Poisson-Boltzmann approximation.Comment: 12 pages, 4 figures, LaTeX fil