Surface roughness detector Patent

Roughness detector for recording surface pattern of irregularitie

Apollo experience report: Lunar module environmental control subsystem

A functional description of the environmental control subsystem is presented. Development, tests, checkout, and flight experiences of the subsystem are discussed; and the design fabrication, and operational difficulties associated with the various components and subassemblies are recorded. Detailed information is related concerning design changes made to, and problems encountered with, the various elements of the subsystem, such as the thermal control water sublimator, the carbon dioxide sensing and control units, and the water section. The problems associated with water sterilization, water/glycol formulation, and materials compatibility are discussed. The corrective actions taken are described with the expection that this information may be of value for future subsystems. Although the main experiences described are problem oriented, the subsystem has generally performed satisfactorily in flight

Dynamic simulation of hydrodynamically interacting suspensions

A general method for computing the hydrodynamic interactions among an infinite suspension of particles, under the condition of vanishingly small particle Reynolds number, is presented. The method follows the procedure developed by O'Brien (1979) for constructing absolutely convergent expressions for particle interactions. For use in dynamic simulation, the convergence of these expressions is accelerated by application of the Ewald summation technique. The resulting hydrodynamic mobility and/or resistance matrices correctly include all far-field non-convergent interactions. Near-field lubrication interactions are incorporated into the resistance matrix using the technique developed by Durlofsky, Brady & Bossis (1987). The method is rigorous, accurate and computationally efficient, and forms the basis of the Stokesian-dynamics simulation method. The method is completely general and allows such diverse suspension problems as self-diffusion, sedimentation, rheology and flow in porous media to be treated within the same formulation for any microstructural arrangement of particles. The accuracy of the Stokesian-dynamics method is illustrated by comparing with the known exact results for spatially periodic suspensions

Breast Cancer: Modelling and Detection

This paper reviews a number of the mathematical models used in cancer modelling and then chooses a specific cancer, breast carcinoma, to illustrate how the modelling can be used in aiding detection. We then discuss mathematical models that underpin mammographic image analysis, which complements models of tumour growth and facilitates diagnosis and treatment of cancer. Mammographic images are notoriously difficult to interpret, and we give an overview of the primary image enhancement technologies that have been introduced, before focusing on a more detailed description of some of our own recent work on the use of physics-based modelling in mammography. This theoretical approach to image analysis yields a wealth of information that could be incorporated into the mathematical models, and we conclude by describing how current mathematical models might be enhanced by use of this information, and how these models in turn will help to meet some of the major challenges in cancer detection

Superfluid Behavior of Active Suspensions from Diffusive Stretching

The current understanding is that the non-Newtonian rheology of active matter suspensions is governed by fluid-mediated hydrodynamic interactions associated with active self-propulsion. Here we discover an additional contribution to the suspension shear stress that predicts both thickening and thinning behavior, even when there is no nematic ordering of the microswimmers with the imposed flow. A simple micromechanical model of active Brownian particles in homogeneous shear flow reveals the existence of off-diagonal shear components in the swim stress tensor, which are independent of hydrodynamic interactions and fluid disturbances. Theoretical predictions from our model are consistent with existing experimental measurements of the shear viscosity of active suspensions, but also suggest new behavior not predicted by conventional models

Psychic costs and factor price equalization

There has been some perplexity among economists over the failure of interregional wage differentials to approach zero over time in an economy characterized by labor mobility. Johnson [7], and Sjaastad [14] , among others, have hypothesized declining wage differentials among regions and have puzzled over contrary empirical results. It has generally been assumed that labor will flow toward regions paying the highest wage rate. This equilibrating framework has dominated economic thought on this problem area and has directed research along narrow market-oriented lines. The hypothesis of this paper is that nonmarket considerations, specifically psychic costs, are a major force in preventing a market-directed flow of human resources. Moreover, "nonoptimal" allocation of human resources results from differences in workers' perceptions of utility between various regions. We will first review the literature in this area and then present an empirical analysis of demographic characteristics suggesting the magnitude of the psychic factor

LISA data analysis I: Doppler demodulation

The orbital motion of the Laser Interferometer Space Antenna (LISA) produces amplitude, phase and frequency modulation of a gravitational wave signal. The modulations have the effect of spreading a monochromatic gravitational wave signal across a range of frequencies. The modulations encode useful information about the source location and orientation, but they also have the deleterious affect of spreading a signal across a wide bandwidth, thereby reducing the strength of the signal relative to the instrument noise. We describe a simple method for removing the dominant, Doppler, component of the signal modulation. The demodulation reassembles the power from a monochromatic source into a narrow spike, and provides a quick way to determine the sky locations and frequencies of the brightest gravitational wave sources.Comment: 5 pages, 7 figures. References and new comments adde

Corticosteroid implants for chronic non-infectious uveitis.

BACKGROUND: Uveitis is a term used to describe a heterogeneous group of intraocular inflammatory diseases of the anterior, intermediate, and posterior uveal tract (iris, ciliary body, choroid). Uveitis is the fifth most common cause of vision loss in high-income countries, accounting for 5% to 20% of legal blindness, with the highest incidence of disease in the working-age population.Corticosteroids are the mainstay of acute treatment for all anatomical subtypes of non-infectious uveitis and can be administered orally, topically with drops or ointments, by periocular (around the eye) or intravitreal (inside the eye) injection, or by surgical implantation. OBJECTIVES: To determine the efficacy and safety of steroid implants in people with chronic non-infectious posterior uveitis, intermediate uveitis, and panuveitis. SEARCH METHODS: We searched CENTRAL (which contains the Cochrane Eyes and Vision Trials Register) (Issue 10, 2015), Ovid MEDLINE, Ovid MEDLINE In-Process and Other Non-Indexed Citations, Ovid MEDLINE Daily, Ovid OLDMEDLINE (January 1946 to November 2015), EMBASE (January 1980 to November 2015), PubMed (1948 to November 2015), Latin American and Caribbean Health Sciences Literature Database (LILACS) (1982 to November 2015), the metaRegister of Controlled Trials (mRCT) (www.controlled-trials.com) (last searched 15 April 2013), ClinicalTrials.gov (www.clinicaltrials.gov), and the World Health Organization (WHO) International Clinical Trials Registry Platform (ICTRP) (www.who.int/ictrp/search/en). We did not use any date or language restrictions in the electronic search for studies. We last searched the electronic databases on 6 November 2015.We also searched reference lists of included study reports, citation databases, and abstracts and clinical study presentations from professional meetings. SELECTION CRITERIA: We included randomized controlled trials comparing either fluocinolone acetonide (FA) or dexamethasone intravitreal implants with standard-of-care therapy with at least six months of follow-up after treatment. We included studies that enrolled participants of all ages who had chronic non-infectious posterior uveitis, intermediate uveitis, or panuveitis with vision that was better than hand-motion. DATA COLLECTION AND ANALYSIS: Two review authors independently reviewed studies for inclusion. Two review authors independently extracted data and assessed the risk of bias for each study. MAIN RESULTS: We included data from two studies (619 eyes of 401 participants) that compared FA implants with standard-of-care therapy. Both studies used similar standard-of-care therapy that included administration of prednisolone and, if needed, immunosuppressive agents. The studies included participants from Australia, France, Germany, Israel, Italy, Portugal, Saudi Arabia, Spain, Switzerland, Turkey, the United Kingdom, and the United States. We assessed both studies at high risk of performance and detection bias.Only one study reported our primary outcome, recurrence of uveitis at any point during the study through 24 months. The evidence, judged as moderate-quality, showed that a FA implant probably prevents recurrence of uveitis compared with standard-of-care therapy (risk ratio (RR) 0.29, 95% confidence interval (CI) 0.14 to 0.59; 132 eyes). Both studies reported safety outcomes, and moderate-quality evidence showed increased risks of needing cataract surgery (RR 2.98, 95% CI 2.33 to 3.79; 371 eyes) and surgery to lower intraocular pressure (RR 7.48, 95% CI 3.94 to 14.19; 599 eyes) in the implant group compared with standard-of-care therapy through two years of follow-up. No studies compared dexamethasone implants with standard-of-care therapy. AUTHORS\u27 CONCLUSIONS: After considering both benefits and harms reported from two studies in which corticosteroids implants were compared with standard-of-care therapy, we are unable to conclude that the implants are superior to traditional systemic therapy for the treatment of non-infectious uveitis. These studies exhibited heterogeneity in design and outcomes that measured efficacy. Pooled findings regarding safety outcomes suggest increased risks of post-implant surgery for cataract and high intraocular pressure compared with standard-of-care therapy