A convergent relaxation of the Douglas-Rachford algorithm

This paper proposes an algorithm for solving structured optimization problems, which covers both the backward-backward and the Douglas-Rachford algorithms as special cases, and analyzes its convergence. The set of fixed points of the algorithm is characterized in several cases. Convergence criteria of the algorithm in terms of general fixed point operators are established. When applying to nonconvex feasibility including the inconsistent case, we prove local linear convergence results under mild assumptions on regularity of individual sets and of the collection of sets which need not intersect. In this special case, we refine known linear convergence criteria for the Douglas-Rachford algorithm (DR). As a consequence, for feasibility with one of the sets being affine, we establish criteria for linear and sublinear convergence of convex combinations of the alternating projection and the DR methods. These results seem to be new. We also demonstrate the seemingly improved numerical performance of this algorithm compared to the RAAR algorithm for both consistent and inconsistent sparse feasibility problems

EFFECT OF LACTOFERRIN TO INCREASE DRUG PERMEABILITY OF PRIMARY PULMONARY MYCOBACTERIAL GRANULOMAS

Despite extensive research and worldwide eradication efforts, Mycobacterium tuberculosis (Mtb) remains a major infectious pathogen to the human population with about 10 million cases of infection per year globally. The host-pathogen interaction, pulmonary granuloma formation, and Mtb adaptions result in increased complexity of the disease. Granulomas are formed by active immune responses generated during Mtb infection, and serve to contain and limit bacterial dissemination. The major mycobacterial surface mycolic acid, trehalose 6,6\u27-dimycolate (TDM), functions in multiple ways to enhance immune cell recruitment of sites of infection, to induce inflammation and granulomatous responses, and to initiate survival strategies for the organism inside macrophages. Mtb also benefits from establishment of a tightly formed granuloma, which both protects it from immune reactivity and serves as a physical boundary to limit penetration of drugs during therapeutic treatment. In order to demystify the complicated relationship between the host and pathogen, many studies have been performed around the primary Mtb-induced granuloma to combat the challenges that come with this specific immunopathology. We hypothesized that by altering the immunopathology of granulomas using lactoferrin, an immunomodulating agent, it will allow greater penetration of therapeutics into the site of focal inflammation. Our lab has reported that oral bovine lactoferrin treatments during the innate immune response leads to significant modulation of the primary Mtb granuloma response and lessen Mtb burden in mouse lungs. Here, we show that such modulation during granuloma development can also be achieved by using recombinant human lactoferrin oral treatments to increase granuloma permeability and promotes drug penetration in both TDM-induced granulomatous inflammation as well as during active Mtb-infection. Findings from this work show lactoferrin’s potential as a host-directed therapeutic that can be combined with current TB standard treatment to reduce pathological damage in the lungs post mycobacterial infection

Using Information and Communication Technology to Support Women\u27s Entrepreneurship in Central and West Asia

Key Points • In several Central and West Asian countries, women are less likely to become entrepreneurs, and their businesses are more likely to be informal, stay small, generate less revenue, and employ fewer people. • Information and communication technology (ICT) tools not only improve business performance but can also be used to overcome challenges specific to women entrepreneurs—time and mobility constraints; access to formal financial services, information, skills, and personalized advice; and participation in business networks. • However, lack of ICT skills, lower purchasing power, and cultural barriers hinder women entrepreneurs from accessing and using ICT. • Governments, financial service providers, and business development service providers have room to more effectively leverage ICT to serve women entrepreneurs. • Women represent an unmet market opportunity for the private sector, opening up public–private partnership options to develop sustainable initiatives and services

DEVELOPING A MATHEMATICAL MODEL FOR HYDRAULIC FRACTURING IN MICROSOFT EXCEL

Many computer software programs have been developed to assist petroleum engineers and scientists in designing hydraulic fractures. These programs use analytical, numerical or empirical methods (or a combination of two or all three methods) to model fracture propagation in the reservoir. The user – which is usually experienced petroleum professional – provides the necessary input parameters to the model. These input parameters include reservoir characteristics, fluid and proppant characteristics. Usually among the major outputs of these models are the fracture geometry and conductivity. The goal of this study is to provide a Mathematical Model of Hydraulic Fracturing Design that allows the engineer to solve the inverse problem in a fast and efficient manner. Using the model developed in this study the engineer identifies the desired fracture geometry that she/he would like to achieve and enters this value along with the reservoir characteristics into the intelligent software tool. The software tool would then solve the inverse problem and provides the engineer with fluid, proppant that would produce the desired fracture in that particular reservoir and well

About [q]-regularity properties of collections of sets

We examine three primal space local Hoelder type regularity properties of finite collections of sets, namely, [q]-semiregularity, [q]-subregularity, and uniform [q]-regularity as well as their quantitative characterizations. Equivalent metric characterizations of the three mentioned regularity properties as well as a sufficient condition of [q]-subregularity in terms of Frechet normals are established. The relationships between [q]-regularity properties of collections of sets and the corresponding regularity properties of set-valued mappings are discussed.Comment: arXiv admin note: substantial text overlap with arXiv:1309.700

Capital Structure and Firm Performance: Evidence from Emerging Markets

This paper investigates the impact of financial leverage on firm performance measured by ROA and ROE in publicly traded enterprises amongst the selected emerging markets, including Brazil, Russia, India and China. Additionally, the study also examines the association of debt equity choice with firm efficiency during a period of extreme distress which is noticeably thought-provoking when considering the emerging markets since debt markets were concerned to trigger for the financial crisis of 2008 penetrating the emerging economies. This study employs data on large, publicly listed companies from the four largest emerging economies including Brazil, Russia, India and China in the period from 2003 to 2013 to observe the effect of financial leverage on firm performance. The thesis investigates whether firm performance is affected by debt equity choice and this relationship if exists persists the same during economic downturns or periods of extreme distress. Empirical results reveals that financial leverage has significantly negative impact on firm performance in tested markets. However, during economic turbulence, this relationship varies from countries to countries. While China and India show that the link is more adverse during recessions, Brazil witnesses a contrary picture when higher level of debt facilitates firm performance during economic downtrends. Russia suggests insignificant relationship between leverage and firm performance measured by both ROA and ROE. Concerning firms experiencing financial distress, the test provides mixed results amongst economies.fi=Opinnäytetyö kokotekstinä PDF-muodossa.|en=Thesis fulltext in PDF format.|sv=Lärdomsprov tillgängligt som fulltext i PDF-format

Efficient GPS Position Determination Algorithms

This research is aimed at improving the state of the art of GPS algorithms, namely, the development of a closed-form positioning algorithm for a standalone user and the development of a novel differential GPS algorithm for a network of users. The stand-alone user GPS algorithm is a direct, closed-form, and efficient new position determination algorithm that exploits the closed-form solution of the GPS trilateration equations and works in the presence of pseudorange measurement noise for an arbitrary number of satellites in view. A two-step GPS position determination algorithm is derived which entails the solution of a linear regression and updates the solution based on one nonlinear measurement equation. In this algorithm, only two or three iterations are required as opposed to five iterations that are normally required in the standard Iterative Least Squares (ILS) algorithm currently used. The mathematically derived stochastic model-based solution algorithm for the GPS pseudorange equations is also assessed and compared to the conventional ILS algorithm. Good estimation performance is achieved, even under high Geometric Dilution of Precision (GDOP) conditions. The novel differential GPS algorithm for a network of users that has been developed in this research uses a Kinematic Differential Global Positioning System (KDGPS) approach. A network of mobile receivers is considered, one of which will be designated the \u27reference station\u27 which will have known position and velocity information at the beginning of the time interval being examined. The measurement situation on hand is properly modeled, and a centralized estimation algorithm processing several epochs of data is developed. The effect of uncertainty in the reference receiver\u27s position and the level of the receiver noise are investigated. Monte Carlo simulations are performed to examine the ability of the algorithm to correctly estimate the non-reference mobile users\u27 position and velocity