The feasibility of a programmed heat shield for solar cell performance control

Feasibility of programmed heat shield for temperature and power control for spacecraft on-board powe

Use of fibre-optic (FBG) sensors in the structural health monitoring of a battlefield helicopter rotor blade

As the use of fibre composite materials and components become more widely accepted, so does the inherent risks of sudden and possibly catastrophic failure. This creates a distinct need for sound, structural health monitoring (SHM) methods to be employed to both warn of, and prevent impending failure. For aviation related fibre composite components this is of paramount importance; however, a secondary but equally important consideration is that of service life. Any extension of a components service life is of great financial and operational benefit to both civil and military operators of aviation assets. This is particularly true of military helicopters which use fibre reinforced composite rotor blades, such as the Boeing CH-47 Chinook. Experience has shown that these highly exposed components are frequently damaged during combat operations and rapidly come into short supply as a result of often minor damage. This minor damage may necessitate blade replacement prior to the aircraft being authorised for further flight. This project seeks to use finite element analysis (FEA) methods and physical blade testing via the use of optical fibre Bragg grating (FBG) sensors to evaluate typical battlefield, ballistic penetration damage by small arms fire projectiles to a composite Boeing CH-47 Chinook rotor blade test section. Abaqus FEA software was used to create both a flat plate simulation and a Boeing-Vertol VR-7 Aerofoil assembly model. Physical testing was conducted on a blade by applying incremental load increases as well as incremental levels of simulated damage. Both FBG and strain gauge systems were used to assess the micro-strain levels at predetermined, critical locations. The data response from these systems was then validated as far as possible by FEA methods, with correlations able to be drawn between the strain systems and the FEA results. This research demonstrated that the use of FBG sensors on the surface of a complex composite component is an appropriate method for determining strains in the vicinity of damage, which was validated in specific areas by FEA methods. It also concluded that FEA methods alone are very difficult to use in a practical sense when assessing the significant size, type and random nature of ballistic damage to a complex composite structure. With further future development the possibility of the embedding FBG sensor systems at manufacture into a composite rotor blade for real time SHM or lifing assessment exists. This may in turn lead to enhanced service life management of such components by moving to an on-condition based lifing approach

Comment on "Drip Paintings and Fractal Analysis", arXiv:0710.4917v2, by K. Jones-Smith, H. Mathur and L.M. Krauss

In a recent manuscript (arXiv:0710.4917v2), Jones-Smith et al. attempt to use the well-established box-counting technique for fractal analysis to "demonstrate conclusively that fractal criteria are not useful for authentication". Here, in response to what we view to be an extremely simplistic misrepresentation of our earlier work by Jones-Smith et al., we reiterate our position regarding the potential of fractal analysis for artwork authentication. We also point out some of the flaws in the analysis presented in by Jones-Smith et al.Comment: Comment on arXiv:0710.4917v2 [cond-mat.stat-mech

Quantification of Plasma and Urine Thymidine and 2'-Deoxyuridine by LC-MS/MS for the Pharmacodynamic Evaluation of Erythrocyte Encapsulated Thymidine Phosphorylase in Patients with Mitochondrial Neurogastrointestinal Encephalomyopathy.

Mitochondrial neurogastrointestinal encephalomyopathy (MNGIE) is an ultra-rare disorder caused by mutations in TYMP, leading to a deficiency in thymidine phosphorylase and a subsequent systemic accumulation of thymidine and 2'-deoxyuridine. Erythrocyte-encapsulated thymidine phosphorylase (EE-TP) is under clinical development as an enzyme replacement therapy for MNGIE. Bioanalytical methods were developed according to regulatory guidelines for the quantification of thymidine and 2'-deoxyuridine in plasma and urine using liquid chromatography-tandem mass spectrometry (LC-MS/MS) for supporting the pharmacodynamic evaluation of EE-TP. Samples were deproteinized with 5% perchloric acid (v/v) and the supernatants analyzed using a Hypercarb column (30 × 2.1 mm, 3 µm), with mobile phases of 0.1% formic acid in methanol and 0.1% formic acid in deionized water. Detection was conducted using an ion-spray interface running in positive mode. Isotopically labelled thymidine and 2'-deoxyuridine were used as internal standards. Calibration curves for both metabolites showed linearity (r > 0.99) in the concentration ranges of 10-10,000 ng/mL for plasma, and 1-50 µg/mL for urine, with method analytical performances within the acceptable criteria for quality control samples. The plasma method was successfully applied to the diagnosis of two patients with MNGIE and the quantification of plasma metabolites in three patients treated with EE-TP

Multilevel Hierarchical Decomposition of Finite Element White Noise with Application to Multilevel Markov Chain Monte Carlo

In this work we develop a new hierarchical multilevel approach to generate Gaussian random field realizations in an algorithmically scalable manner that is well-suited to incorporate into multilevel Markov chain Monte Carlo (MCMC) algorithms. This approach builds off of other partial differential equation (PDE) approaches for generating Gaussian random field realizations; in particular, a single field realization may be formed by solving a reaction-diffusion PDE with a spatial white noise source function as the righthand side. While these approaches have been explored to accelerate forward uncertainty quantification tasks, e.g. multilevel Monte Carlo, the previous constructions are not directly applicable to multilevel MCMC frameworks which build fine scale random fields in a hierarchical fashion from coarse scale random fields. Our new hierarchical multilevel method relies on a hierarchical decomposition of the white noise source function in $L^2$ which allows us to form Gaussian random field realizations across multiple levels of discretization in a way that fits into multilevel MCMC algorithmic frameworks. After presenting our main theoretical results and numerical scaling results to showcase the utility of this new hierarchical PDE method for generating Gaussian random field realizations, this method is tested on a four-level MCMC algorithm to explore its feasibility

Retroperitoneal hematoma following hysteroscopic removal of levonorgestrel intrauterine system: a case report

Long acting reversible contraceptive (LARC) devices such as the levonorgestrel intrauterine system (LNG-IUS) have increased in use. Care should be taken with insertion and removal of the device as, although rare, serious complications can occur. We present a case of retroperitoneal hematoma following hysteroscopic removal of LNG-IUS

The influence of air-sea exchange on the isotopic composition of oceanic carbon: Observations and modeling

Although the carbon isotopic composition of ocean waters after they leave the surface ocean is determined by biological cycling, air-sea exchange affects the carbon isotopic composition of surface waters in two ways. The equilibrium fractionation between oceanic and atmospheric carbon increases with decreasing temperature. In Southern Ocean Surface Waters this isotopic equilibration enriches δ13C relative to the δ13C expected from uptake and release of carbon by biological processes alone. Similarly, surface waters in the subtropical gyres are depleted in δ13C due to extensive air-sea exchange at warm temperatures. Countering the tendency toward isotopic equilibration with the atmosphere (a relatively slow process), are the effects of the equilibration of CO2 itself (a much faster process). In regions where there is a net transfer of isotopically light CO2 from the ocean to the atmosphere (e.g., the equator) surface waters become enriched in 13C, whereas in regions where isotopically light CO2 is entering the ocean (e.g., the North Atlantic) surface waters become depleted in 13C. A compilation of high quality oceanic δ13C measurements along with experiments performed using a zonally averaged three-basin dynamic ocean model are used to explore these processes

Eficiencia energética: estrategias aplicadas en el nuevo edificio de las Consejerías de Mérida (España)

The architecture office GOP was awarded the execution of the project for the regional government office building “Consejerías”) in the city of Mérida, designed by Bruce S. Fairbanks, through an International Competition of Ideas summoned by the Junta de Extremadura. The new Consejerías in Mérida set the standards for a wholly sustainable building. It modifies its natural outdoors environment by soothing the climate and giving shelter. A design strategy was, among others, to gain as much confort as possible inside the building: thermal confort, visual confort, indoor air quality and acoustic quality. The new Consejerías underlying precept is to make a simple building, so they are designed to meet all these objectives by taking full advantage of architectonic means rather than requesting to technical fixtures for the conditioning of their indoor environment. The system designed to benefit from the inertia of the soil as a buffer for the building interior temperatures has never been used in Spain in large facilities, because they require large air volumes due to their low specific temperature. In this case, an air-to-earth heat exchanger was included in the project for a large institutional building.El Estudio GOP ha obtenido la adjudicación del proyecto del edificio de Consejerías en la ciudad de Mérida, diseñadas por Bruce S. Fairbanks, mediante el Concurso Internacional de Ideas convocado por la Junta de Extremadura. Las nuevas Consejerías de Mérida se constituyen como un ejemplo de edificio sostenible en todos sus aspectos. El edificio modifica el entorno natural externo moderando el clima y ofreciendo protección y cobijo. Entre las estrategias seguidas al diseñarlo está obtener el máximo confort en el interior: confort térmico, confort visual, calidad del aire interno y calidad acústica. Las nuevas Consejerías están diseñadas para alcanzar todos estos objetivos, manteniendo la idea subyacente de un edificio simple y obteniendo el máximo rendimiento de los recursos arquitectónicos antes de apelar a las instalaciones para el acondicionamiento del ambiente interno. La propuesta incorpora el intercambiador tierra-aire a un edificio institucional de gran tamaño. El sistema diseñado para utilizar la inercia del terreno como regulador parcial de las temperaturas interiores del edificio no se ha empleado nunca en grandes instalaciones en España, debido a que se requieren grandes volúmenes de aire por su bajo calor específico

Validity and Reliability of Electronic Devices to Measure Muscular Power during Linear Weight Lifting Movements

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A compositional account of motifs, mechanisms, and dynamics in biochemical regulatory networks

Regulatory networks depict promoting or inhibiting interactions between molecules in a biochemical system. We introduce a category-theoretic formalism for regulatory networks, using signed graphs to model the networks and signed functors to describe occurrences of one network in another, especially occurrences of network motifs. With this foundation, we establish functorial mappings between regulatory networks and other mathematical models in biochemistry. We construct a functor from reaction networks, modeled as Petri nets with signed links, to regulatory networks, enabling us to precisely define when a reaction network could be a physical mechanism underlying a regulatory network. Turning to quantitative models, we associate a regulatory network with a Lotka-Volterra system of differential equations, defining a functor from the category of signed graphs to a category of parameterized dynamical systems. We extend this result from closed to open systems, demonstrating that Lotka-Volterra dynamics respects not only inclusions and collapsings of regulatory networks, but also the process of building up complex regulatory networks by gluing together simpler pieces. Formally, we use the theory of structured cospans to produce a lax double functor from the double category of open signed graphs to that of open parameterized dynamical systems. Throughout the paper, we ground the categorical formalism in examples inspired by systems biology.Comment: 33 pages. Added several examples, plus minor revision