Failures of weak approximation in families

Given a family of varieties $X\to \mathbb{P}^n$ over a number field $k$, we determine conditions under which there is a Brauer-Manin obstruction to weak approximation for $100\%$ of the fibres which are everywhere locally soluble.Comment: 44 pages; there is a new application to integral points (Theorem 1.4) and Cor 1.5 recovers a well-known result concerning the Hasse principl

Jet Makers: The Aerospace Industry from 1945 to 1972

This volume presents the history of the American jet aircraft manufacturing industry from World War II to 1972, documenting the evolution of its technology and covering the intricacies of its management, economics, and relations with the government. A valuable contribution to general aviation history, it also provides a unique opportunity to study the dynamic of a major U.S. industry. Charles D. Bright traces the momentous revolution of the aerospace era from birth to maturity, using as a base the jet aircraft industry. He investigates all significant aspects: the coming-of-age of aviation during World War II, including global transportation and aerodynamics; the development of jets and missiles from the Truman era to the Vietnam War; the controlling influence of national military strategy; the U.S. Air Force and other government markets; the mechanics of government procurement—bidding, pricing, buying; difficulties in the commercial airliner business; the ordering of technology and the prevailing “design or die” philosophy; and different systems of production through the years. Special attention is given to major problems such as the industry’s need for diversification and the skyrocketing costs that threaten to make aerospace products uneconomical. The conventional economic concerns of entry into and exit from the industry are treated in depth. Bright focuses on the overall economic pattern, from the first demand for aerospace machines for military, space, and commercial uses to the failures of recent times as the industry entered recession and peacetime equilibrium. He tells of the desperate competition among giants of the industry, those companies on the frontiers of technology that manufactured fixed-wing aircraft of their own design. This is the group that bore the brunt of adaptation to the jet age: Boeing, Curtiss-Wright, Douglas, Fairchild, General Dynamics, Grumman, Lockheed, martin, McDonnell, North American Northrop, and Republic. Central to the story are the reasons for Americas leadership in the jet age: enterprising business managers, scientists, and engineers; the pressure of economics; and manifold competition brought on by economics; and manifold competition brought on by the cold war. Bright points to an industry that has responded to incredible demands and that has shown the strength to weather storms. This volume is illustrated with fifty-five photographs depicting the growth in aircraft technology from 1945 to 1972. As a unique blend of aeronautic, economic, business, and military history, it will fascinate not only those connected with aviation and the aerospace industry, but also those interested in the history of technology, business management, and government-military-business relations. The Jet Makers received Honorable Mention in the 1977 History Manuscript award competition of the American Institute of Aeronautics and Astronautics. Description Lt. Col Charles D. Bright (1921–2014) was World War II Eighth Army Air Force lead B-17 navigator and flew fighter jets during the Korean War. After receiving his Ph.D. in history from Kansas State University he became professor of business administration at Southwestern College, and later went on to found and chair the business and economics department at Mt. St. Clare College. Roger D. Launius retired in 2016 as Associate Director for Collections and Curatorial Affairs, National Air and Space Museum, Smithsonian. From 1990 to 2002 he served as chief historian for the National Aeronautics and Space Administration (NASA). His numerous publications include Exploring the Solar System: The History and Science of Planetary Probes and Spaceflight and the Myth of Presidential Leadership, coauthored with Howard E. McCurdy. This Kansas Open Books title is funded by a grant from the National Endowment for the Humanities and the Andrew W. Mellon Foundation Humanities Open Book Program.https://digitalcommons.pittstate.edu/kansas_open_books/1006/thumbnail.jp

Comparison of Ultrasound-Guided Vs Traditional Arterial Cannulation by Emergency Medicine Residents

Introduction: We sought to determine whether ultrasound-guided arterial cannulation (USGAC) is more successful than traditional radial artery cannulation (AC) as performed by emergency medicine (EM) residents with standard ultrasound training.Methods: We identified 60 patients age 18 years or older at a tertiary care, urban academic emergency department who required radial AC for either continuous blood pressure monitoring or frequent blood draws. Patients were randomized to receive radial AC via either USGAC or traditional AC. If there were three unsuccessful attempts, patients were crossed over to the alternative technique. All EM residents underwent standardized, general ultrasound training.Results: The USGAC group required fewer attempts as compared to the traditional AC group (mean 1.3 and 2.0, respectively; p<0.001); 29 out of 30 (96%) successful radial arterial lines were placed using USGAC, whereas 14 out of 30 (47%) successful lines were placed using traditional AC (p<0.001). There was no significant difference in length of procedure or complication rate between the two groups. There was no difference in provider experience with respect to USGAC vs traditional AC.Conclusion: EM residents were more successful and had fewer cannulation attempts with USGAC when compared to traditional AC after standard, intern-level ultrasound training.

New observations regarding deterministic, time reversible thermostats and Gauss's principle of least constraint

Deterministic thermostats are frequently employed in non-equilibrium molecular dynamics simulations in order to remove the heat produced irreversibly over the course of such simulations. The simplest thermostat is the Gaussian thermostat, which satisfies Gauss's principle of least constraint and fixes the peculiar kinetic energy. There are of course infinitely many ways to thermostat systems, e.g. by fixing $\sum\limits_i{|{p_i}|^{\mu + 1}}$. In the present paper we provide, for the first time, convincing arguments as to why the conventional Gaussian isokinetic thermostat ($\mu=1$) is unique in this class. We show that this thermostat minimizes the phase space compression and is the only thermostat for which the conjugate pairing rule (CPR) holds. Moreover it is shown that for finite sized systems in the absence of an applied dissipative field, all other thermostats ($\mu=1$) perform work on the system in the same manner as a dissipative field while simultaneously removing the dissipative heat so generated. All other thermostats ($\mu=1$) are thus auto-dissipative. Among all $\mu$-thermostats, only the $\mu=1$ Gaussian thermostat permits an equilibrium state.Comment: 27 pages including 10 figures; submitted for publication Journal of Chemical Physic

Discourse and identity in a corpus of lesbian erotica

This article uses corpus linguistic methodologies to explore representations of lesbian desires and identities in a corpus of lesbian erotica from the 1980s and 1990s. We provide a critical examination of the ways in which “lesbian gender,” power, and desire are represented, (re-)produced, and enacted, often in ways that challenge hegemonic discourses of gender and sexuality. By examining word frequencies and collocations, we critically analyze some of the themes, processes, and patterns of representation in the texts. Although rooted in linguistics, we hope this article provides an accessible, interdisciplinary, and timely contribution toward developing understandings of discursive practices surrounding gender and sexuality

Analysis of surface tris (2,3-dibromopropyl) phosphate on chlorobutyl rubber SCAPE suits

Tris (2,30-dibromopropyl) phosphate was used to confer flame retardant properties on butyl rubber formulations used in protective clothing such as the self-contained atmospheric protective ensembles (SCAPE suits) worn at Kennedy Space Center in support of Apollo, Skylab, and Apollo-Soyuz missions since 1966. Because tris (2,3-dibromopropyl) phosphate is mutagenic, surface concentrations of the compound in SCAPE suits were investigated as were as potential methods of removing or isolating it. Analytical procedures for determining surface concentrations of the tris compound on non-porous materials are described. Soap-and-water washing is the most efficient method of removing the compound from fabricated SCAPE suits and unused material

The Ursinus Weekly, May 8, 1944

Newcomers to take 12 of the 18 roles in Curtain Club play • Dr. Max Lerner to address community forum on post war problems of our democracy • Beverly Cloud to sing in The Red Mill • Hunter explains pharisees\u27 question • Debate clubs active on national question • WSSF sets up hostels for Chinese students • Students to have last vote on proposed constitution • Ursinus library clock is copy of Big Ben • Blood donor unit coming • Land of Oz dancers, committees at work on May pageant to be given May 20 • Four girls, one boy win $350 open scholarships • IRC elects six members • Miss Spangler to present a study of Verdi\u27s Aida • Little Oswald finds beauties on campus • Courtesy on the courts • Bear baseball men wallop Drew nine as Snyder pitches second straight win • Softball team downs Collegeville-Trappe H. S. • Four Ursinus girls enter third round of intercollegiate tennis tournament • Bears swamp PMC 14-0; Snyder twirls one hitterhttps://digitalcommons.ursinus.edu/weekly/1732/thumbnail.jp

NEET Speaks: Influences Shaping Young People’s Choices of Education, Training and Employment

The research approach adopted is based on the fundamental belief that young people gain benefits from their experience within their social and geographical communities, i.e. neighbourhoods, which are often not formally recognised. The project explored the extent to which hard-to-reach individuals’ learning and career development needs are currently being met. It focused in particular on emerging themes based on young people’s experiences of family, community, learning and work