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peer-reviewed Increasing applications of laminated composite structures necessitate the development of equivalent single layer (ESL) models that can achieve similar accuracy but are more computationally efficient than 3D or layer-wise models. Most ESL displacement-based models do not guarantee interfacial continuity of shear stresses within laminates. A possible remedy is the enforcement of interlaminar equilibrium in variational formulations, for example, in the framework of the Hellinger-Reissner variational principle, leading to a mixed force/displacement model. In this paper, the governing equations for bending and stretching of laminated beams, comprising only seven stress resultants and two displacement functionals, are obtained using global fifth-order and a local linear zigzag kinematics. As a strong-form solution technique, the differential quadrature method (DQM) is an efficient tool which can provide excellent convergence with relatively few number of grid points. However, in dealing with high-order differential equations, the conventional DQM can incur considerable errors due to the nature of numerical differentiation. Therefore, a mixed inverse differential quadrature method (iDQM) is proposed herein to solve the governing fourth-order differential equations for bending and stretching of laminated beams. This approach involves approximating the first derivatives of functional unknowns, thereby reducing the order of differentiation being performed. Using a non-uniform Chebychev-Gauss-Lobatto grid point profile, numerical results show that the accuracy of stress predictions is improved by using iDQM compared to DQM. In addition, the Cauchy’s equilibrium condition is satisfied more accurately by iDQM, especially in the vicinity of boundaries

The SuperMarineOne project focuses on numerical modelling and analysis of superconducting cables in operation and installation. Firstly, an overview of the current developments in superconducting cables was presented and issues with subsea cables that will affect submarine applications of superconducting cables are discussed and compared. Potential marine applications of superconducting cables in Ireland such as existing and proposed interconnectors and offshore wind farms were reviewed and analysed. A new design methodology for high temperature superconducting (HTS) cables to be used in marine applications is proposed. In addition, detail non-linear finite element models are developed to calculate the axial and bending stiffnesses of conventional HTS cables which have not been appropriately reported in public literature. From the conclusion that conventional HTS cables are not suitable for dynamic marine application, a novel structural concept for HTS cables is presented that enables such applications of the technology. Finally, the suitability of cable laying and reel-lay vessels to install the HTS cable is reviewed and the effect of wave and current directions, wave peak periods and water depth during the installation process is investigated. The studies carried out in the project find out that: Currently, three HTS materials have been demonstrated worldwide for SC cable applications i.e. BSCCO, YBCO and MgB2. Although there are several deployed and ongoing demonstration superconducting cable projects worldwide, no clear direction of which superconducting material is preferred for power cable applications. There are potential marine applications of superconducting technology in Ireland for adequate infrastructure and technology for offshore transmission and interconnectors in order to deploy large-scale electricity. Besides, there is huge potential for introducing superconducting technology for export cables and collectors in offshore wind farms to exploit the offshore wind potential of 34.8 GW – 39 GW in Ireland. Coupling with other energy sectors by the concepts of offshore wind – hydrogen production hubs being developed by the H-Wind project ([1]) is another solution to increase the applications of superconducting technology. The free-hanging configuration is more suitable than the lazy-wave configuration for HTS cable applications at 100 m water depths. Even though the lazy wave configuration minimized the top tension on the cable, the addition of buoyant modulus introduced excessive axial compression that led to cable buckling in both designs. This occurs because the HTS cable is light in comparison to its external diameter and consequently its water displacement. According to the methodology proposed in the project, conventional HTS cable designs used in terrestrial applications are not suitable for dynamic marine applications. In order to allow HTS cables to be deployed in the marine environment an external armour structure to support the marine loads is required. The novel structural concept for HTS cables specific for marine applications satisfies all design criteria in the extreme operation and installation conditions evaluated. This could enable further investigations and deployment of HTS technology in a number of marine applications. By comparing cable laying and reel-lay vessels, the latter is considered more suitable to install the HTS cable proposed. However, some cable laying vessels may be able to install the HTS cable. Having two different types of vessels available for installations could be another advantage. From an installation perspective, the critical environmental load direction for cable installation is caused by transversal waves (90o direction). However, this environmental load direction showed to only induce significant stresses to the HTS cable in a limited range of wave peak periods near the vessel’s natural frequency of vibration in roll. The results also show that the pipe releasing ramp support is responsible for inducing significant bending moments to the HTS cable during installation. [1] https://www.marei.ie/project/h-wind/

Bamboo poles, and other one-dimensional thin-walled structures are usually loaded under compression, which may also be subject to bending arising from eccentric loading. Many of these structures contain diaphragms or circumferential stiffeners to prevent cross-sectional distortions and so enhance overall load-carrying response. Such hierarchical structures can compartmentalize buckling to local regions in addition to withstanding global buckling phenomena. Predicting the buckling mode shapes of such structures for a range of geometric parameters is challenging due to the interaction of these global and local modes. Abaqus finite element software is used to model thousands of circular hollow tubes with random geometric parameters such that the ratios of radius to periodic length range from 1/3-1/7, the ratio of wall thickness to radius varies from 1/4-1/10. The material used in this study is a type of bamboo, where the Young’s and shear moduli are point-wise orthotropic and gradually increase in magnitude in the radial direction. Under eccentric loads with varying eccentricity, the structures can buckle into a global mode or local modes within an internode, i.e. periodic unit. Moreover, the local modes may contain only one wave or multiple waves in the circumferential direction. As expected, numerical results show that the global mode is more likely to occur in small and thick tubes, whereas the local modes are observed in larger tubes with a smaller number of circumferential waves present in thicker walls. Also, greater eccentricity pushes the local mode domains towards smaller tubes. An efficient classification method is developed herein to identify the domains of each mode shape in terms of radius, wall thickness and eccentricity. Based on linear discriminant analysis, explicit boundary surfaces for the three domains are defined for the obtained data, which can help designers in predicting the mode shapes of tubular structures under axial bending.

Engineering systems are typically governed by systems of high-order differential equations which require efficient numerical methods to provide reliable solutions, subject to imposed constraints. The conventional approach by direct approximation of system variables can potentially incur considerable error due to high sensitivity of high-order numerical differentiation to noise, thus necessitating improved techniques which can better satisfy the requirements of numerical accuracy desirable in solution of high-order systems. To this end, a novel inverse differential quadrature method (iDQM) is proposed for approximation of engineering systems. A detailed formulation of iDQM based on integration and DQM inversion is developed separately for approximation of arbitrary low-order functions from higher derivatives. Error formulation is further developed to evaluate the performance of the proposed method, whereas the accuracy through convergence, robustness and numerical stability is presented through articulation of two unique concepts of the iDQM scheme, known as Mixed iDQM and Full iDQM. By benchmarking iDQM solutions of high-order differential equations of linear and nonlinear systems drawn from heat transfer and mechanics problems against exact and DQM solutions, it is demonstrated that iDQM approximation is robust to furnish accurate solutions without losing computational efficiency, and offer superior numerical stability over DQM solutions.

peer-reviewed Elastic boundary conditions play an important role in the buckling analysis of cylinders under compressive loading. These structures are used widely in aerospace applications and are highly sensitive to geometrical, material, loading, and boundary imperfections. In fact, the presence of these imperfections can lead to catastrophic failure. In 1968, NASA reported relations for obtaining the Knockdown Factor (KDF) based on an empirical method that is valid for isotropic and orthotropic materials; however, these relations do not consider the effect of elastic boundaries that can lead to highly conservative values of KDF. In design practice, a universal KDF of 0.65 has been used for recent designs by NASA, which may not be applicable to new types of structural configuration with different loading and boundary conditions. Therefore, there is a need for robust design factors for future designs which reduce the dependency on testing during preliminary design phases and speeds up the product development process. The availability of up‐to‐date and different KDF expressions for different structural configurations would help engineers to design lighter structures with improved load carrying capacity and reliability. The main objective of this work is to identify the buckling load sensitivity of cylindrical shells due to their boundary conditions and develop KDF relations considering elastic boundaries. To achieve this goal, the effect of axial, radial and tangential support stiffness on a quasi‐isotropic cylinder under axial compression is investigated. A data‐driven design approach is used to develop new KDF empirical relations for a quasi‐isotropic cylinder on different elastic foundations. The accuracy of these relations is within 5% for any elastic foundation considered.

Background and aims: Fibrosis-4 (FIB-4) index is a HCC predictor in chronic hepatitis B (CHB) patients. However, little is known about whether FIB-4 helps identify non-cirrhotic CHB patients with minimal HCC risk after prolonged nucleos(t)ide analogue (NA) therapy. Methods: A total of 1936 ethnically diverse, non-cirrhotic CHB patients were enrolled in this retrospective multi-national study. All patients received prolonged NA treatment, including entecavir and tenofovir disoproxil fumarate. We explored whether FIB-4 cutoff of 1.30, a marker indicative of mild fibrosis severity, could stratify HCC risks in these patients. Results: A total of 48 patients developed HCC after a mean follow-up of 6.98 years. FIB-4 level at 1 year after treatment (1-year FIB-4) was shown to be associated with HCC development and was superior to pre-treatment FIB-4 value. When patients were stratified by 1-year FIB-4 of 1.30, the high FIB-4 group was at an increased HCC risk compared to the low FIB-4 group, with a hazard ratio of 4.87 (95% confidence interval: 2.48–9.55). Multivariable analysis showed that sex and 1-year FIB-4 were independent predictors, with none of the 314 female patients with low 1-year FIB-4 developing HCC. Finally, 1-year FIB-4 of 1.30 consistently stratified HCC risks in patients with low PAGE-B score, a score composed of baseline age, sex and platelet count, and the annual incidence rate of HCC was 0.11% in those with PAGE-B < 10 + 1-year FIB-4 < 1.30. Conclusions: In non-cirrhotic CHB patients receiving prolonged NA therapy, 1-year FIB-4 < 1.30 is useful for identifying those with minimal HCC risk by combining with female sex or low PAGE-B score. © 2021, Asian Pacific Association for the Study of the Liver.

peer-reviewed The full text of this item will not be available in ULIR until the embargo expires on the 28/10/2021 The buckling behavior of bamboo culm is highly affected by internodal properties, i.e. material properties and geometric parameters of the trunk. In this study, the effects of Phyllostachys Edulis bamboo culms have on buckling phenomena under bending and compressive loads are investigated. Internodal walls are assumed to be composed of orthotropic functionally graded-type materials which are controlled by the volume fraction of the vascular fiber bundle. Provided that the trunk wall thickness near the node is greater than that in the internode and that the number of fibers is mostly unchanged, the internode and node walls are defined by shell elements with the same composite layup material but different thicknesses. It is found that, with a constant internodal length the buckling behavior transitions from global to local as the tube radius increases. The global buckling load increases with approximately a fourth order polynomial in relation with the radius while the local buckling load linearly increases with the tube radius. Nodal wall thickening enhances the buckling load in both the global and local domains. There is an interactive contribution of nodal wall and diaphragm thicknesses on the buckling behavior up to a certain point where the local buckling load is independently determined by each internodal structure. The buckle can occur within thin diaphragms, which results in much lower buckling load compared with the tube without/removed the diaphragms. PUBLISHED peer-reviewed

peer-reviewed The full text of this article will not be available in ULIR until the embargo expires on the 07/01/2022 A novel strain-displacement variational formulation for the flexural behaviour of laminated composite beams is presented, which accurately predicts three-dimensional stresses, yet is computationally more efficient than 3D finite element models. A global third-order and layer-wise zigzag profile is assumed for the axial deformation field to account for the effect of both stress-channelling and stress localisation. The axial and couple stresses are evaluated from the displacement field, while the transverse shear and transverse normal stresses are computed by the interlaminar-continuous equilibrium conditions within the framework of the modified couple stress theory. Then, axial and transverse force equilibrium conditions are imposed via two Lagrange multipliers, which correspond to the axial and transverse displacements. Using this mixed variational approach, both displacements and strains are treated as unknown quantities, resulting in more functional freedom to minimise the total strain energy. The differential quadrature method is used to solve the resulting governing and boundary equations for simply-supported, clamped and cantilever laminated beams. The deflections and stresses from this variational formulation for simply supported beams agree well with those from a Hellinger-Reissner stress-displacement mixed model found in the literature and the 3D elasticity solution given by Pagano. These strain-displacement models also accurately predict the localised stresses near clamped and free boundaries, which is confirmed by the high-fidelity Abaqus models. ACCEPTED peer-reviewed

peer-reviewed The full text of this article will not be available in ULIR until the embargo expires on the 28/10/2021 In this study, we use the stochastic finite element method for vibration analysis of functionally graded (FG) Euler-Bernoulli beams considering variability in material properties. The selected FG material consists of a mix of ceramic and metal constituents. The material properties of the FG beams studied are assumed to vary smoothly over the depth according to a power law. Constituent material properties such as the Young’s modulus, mass density and volume fraction index are modeled as random variables. For each simulation of these random parameters, finite element method is employed to estimate natural frequencies of FG beam. Several simulations need to be carried out for propagating overall inputs uncertainty to stochastic frequencies that are approximated as a series in an orthogonal space. The components of series will be determined based on both polynomial chaos expansion (PCE) and stochastic collocation (SC) methods. For PCE, the multivariate Hermite orthogonal functions are derived using Askey scheme. Their coefficients are estimated using both spectral projection, linear regression approaches. Standard tensor product is used to integrate the multi-dimensional integrals. In term of SC method, basis functions are Lagrange interpolation functions formed for known coefficients called collocation points. Postanalysis including reliability, sensitivity and distribution of uncertain frequencies are also studied. These results will also be compared with those of Monte Carlo Simulation.

© 2018 Elsevier Ltd The size-dependent static, free vibration and buckling behaviours of functionally graded (FG) sandwich plates are analysed in this study. Utilising the modified couple stress theory and variational principle, governing equations of motion are developed with a refined shear deformation theory. The rectangular plates embedded on two opposite simply-supported edges with the arbitrary combinations of the other two. Based on the state-space Levy solution, the deflections, stresses, natural frequencies and critical buckling loads are analytically solved for the closed-form formulations. The effects of material distribution and graded schemes, geometric parameters and boundary conditions are also investigated to examine the size-dependent behaviours of FG sandwich microplates.

© 2017 Elsevier Ltd In this paper, the free vibration behaviour of bi-dimensional functionally graded (BDFG) microbeams under arbitrary boundary conditions (BCs) is studied. Based on the frame work of the modified couple stress theory and Hamilton's principle, governing equations of motion are developed for the BDFG microbeams using a quasi-3D theory. The formula then can be reduced to a higher-order beam theory (HOBT) of conventional functionally graded (FG) microbeams with the material properties varying along the thickness direction only. Two types of BDFG microbeams with different patterns of material volume distribution are considered. The material properties used in this study are assumed to vary exponentially along both longitudinal and thickness directions of microbeams. Based on the state-space concept, the governing equations are solved for natural frequencies and vibration mode shapes of microbeams under various BCs. The effects of material distribution, geometric parameters and BCs are also investigated to examine the size-dependent behaviour of BDFG microbeams.

Cylindrical shells under compressive loading are highly sensitive to boundary conditions. Considering that these structures are connected by surrounding structural components with finite stiffness, an accurate evaluation of the effects of their boundary stiffness is crucial in their design. As such, this work investigates the effect of elastic boundary conditions on the linear buckling behaviour of cylindrical shells under compressive loading. To achieve this goal, a virtual testing investigation on the effect of translational and rotational constraints to the linear buckling response of a quasi-isotropic cylinder subjected to axial compression is performed. Subsequently, the effect of many kinds of constraints on linear buckling behaviour is discussed and interesting insights regarding a significant coupling effect between the radial and tangential translational constraints are given. Results obtained from virtual testing show that seven recurrent buckling mode shapes occur with seven corresponding similar linear buckling loads. Therefore, based on these similarities, seven groups of classical boundary conditions are introduced to classify all possible linear buckling behaviours exhibited by the cylinder under consideration. Finally, these findings can support the development of theoretical models for cascade, or flange, designs of multiple connecting cylinders.

This paper presents the static bending, free vibration and buckling behaviours of functionally graded sandwich microplates under mechanical and thermal loads. Governing equations of both higher-order shear deformation and quasi-3D theories are derived based on the variational principle and modified couple stress theory. Apart from mechanical load, the temperature profiles considered are either uniform or linear distribution through the thickness, which results in changes of material properties and stress resultants. Numerical results are obtained using Navier solutions. The difference between quasi-3D and 2D models in dealing with mechanical and thermal load is discussed. Temperature-dependent and temperature-independent material properties are examined. The effects of geometry and power-law index together with mechanical loads and various temperature distributions on the size-dependent behaviours of functionally graded sandwich plates are also investigated.

Summary The Phu Khanh basin is a rifted continental margin formed by Paleogen rifting and subsequent post-rift subsidence. The basin is situated along the narrowest part of the Bien Dong Sea’s shelf and is characterized by a water depth ranging from a few tens of meters to abyssal depths towards the east. The Carbonates growth initiated during the late Early Miocene along the open marine Vietnamese margin and continued throughout to late Miocene. During this period, the structural grain, tectonic conditions as well as oceanographic eiects exerted major controls on carbonate deposition. The Carbonate Platform located in the South-western part of the Phu Khanh Basin is one of the largest carbonate platforms in the South China Sea while Carbonate Built-up within the Early-Mid Miocene sequences are considered the most prospective reservoir of the Phu Khanh Basin. In addition, the other type of Carbonate - reefs may be present in the deep waters of Phu Khanh form important targets for petroleum exploration. The purpose of this paper is to present the Carbonates Characterzation and its Evolution during the post-rift period in the Phu Khanh Basin.

The state space approach is used to provide analytical solution for fundamental frequency analysis of functionally graded sandwich beams. The classical beam theory, first-order and higher-order shear deformation theories are employed to consider beams of various classical and non-classical boundary conditions. Governing equations of motions are derived from Hamilton’s principle. The research investigates the effect of boundary conditions on the fundamental frequency with nine combinations of classical boundary conditions created from clamped, hinged, pinned and free conditions in accordance with three combinations of non-classical boundary conditions created from the assumption of an elastic support. In addition, the influence of material parameter and arrangement of layers as well as the slenderness ratio in vibration of functionally graded sandwich beams is examined.

This study investigates the mechanical behaviours of functionally graded (FG) microbeams based on the modified couple stress theory. The material properties of these beams are varied through beam’s depth and calculated by using classical rule of mixture and Mori–Tanaka scheme. The displacement fields are presented by using a unified framework which covers various theories including classical beam theory, first-order beam theory, third-order beam theory, sinusoidal beam theory, and quasi-3D beam theories. The governing equations of bending, vibration and buckling problems are derived using the Hamilton’s principle and then solved by using Navier solutions with simply-supported boundary conditions. A number of numerical examples are conducted to show the validity and accuracy of the proposed approaches. Effects of Poisson’s ratio, material length scale parameter, power-law index, estimation methods of material properties and slenderness ratio on deflections, stresses, natural frequencies and critical buckling loads of FG microbeams are examined.

An analytical method for vibration and buckling behaviours of Functionally Graded (FG) beams with various boundary conditions under mechanical and thermal loads is presented. Based on linear strain-displacement relations, equations of motion and essential boundary conditions are derived from Hamilton’s principle. In order to account for thermal effects, three cases of the temperature rise through the thickness, which are uniform, linear and nonlinear, are considered. The exact solutions are derived using the state space approach. Numerical results are presented to investigate the effects of boundary conditions, temperature distributions, material parameters and slenderness ratios on the critical temperatures, critical buckling loads, and natural frequencies as well as load-frequencies curves, temperature-frequencies curves of FG beams under thermal/mechanical loads. The accuracy and effectiveness of proposed model are verified by comparison with previous research.

The Stratospheric Observatory for Infrared Astronomy (SOFIA) is NASA’s airborne observatory. Observing with SOFIA has different challenges than observing from a ground based, or even space-based observatory. Although pointing SOFIA is similar to pointing an alt/az telescope, positioning the telescope requires not only the telescope assembly but also the aircraft. SOFIA’s telescope assembly can move in altitude nominally between 20∘ and 60∘. Since the telescope is pointed out the left side of a modified Boeing 747, the azimuth is determined by the aircraft heading. As a result, observing plans become the basis for a flight plan, and the science observation and aircraft operations are intrinsically linked. This paper will discuss flight planning and execution on this unique observatory.

This paper describes the design and performance of a 50 liter, two-segment $^{6}$Li-loaded liquid scintillator detector that was designed and operated as prototype for the PROSPECT (Precision Reactor Oscillation and Spectrum) Experiment. The two-segment detector was constructed according to the design specifications of the experiment. It features low-mass optical separators, an integrated source and optical calibration system, and materials that are compatible with the $^{6}$Li-doped scintillator developed by PROSPECT. We demonstrate a high light collection of 850$\pm$20 PE/MeV, an energy resolution of $\sigma$ = 4.0$\pm$0.2% at 1 MeV, and efficient pulse-shape discrimination of low $dE/dx$ (electronic recoil) and high $dE/dx$ (nuclear recoil) energy depositions. An effective scintillation attenuation length of 85$\pm$3 cm is measured in each segment. The 0.1% by mass concentration of $^{6}$Li in the scintillator results in a measured neutron capture time of $\tau$ = 42.8$\pm$0.2 $\mu s$. The long-term stability of the scintillator is also discussed. The detector response meets the criteria necessary for achieving the PROSPECT physics goals and demonstrates features that may find application in fast neutron detection., Comment: 16 pages, 13 figures; minor edits to design detail and references

This Letter reports the first scientific results from the observation of antineutrinos emitted by fission products of $^{235}$U at the High Flux Isotope Reactor. PROSPECT, the Precision Reactor Oscillation and Spectrum Experiment, consists of a segmented 4 ton $^6$Li-doped liquid scintillator detector covering a baseline range of 7-9 m from the reactor and operating under less than 1 meter water equivalent overburden. Data collected during 33 live-days of reactor operation at a nominal power of 85 MW yields a detection of 25461 $\pm$ 283 (stat.) inverse beta decays. Observation of reactor antineutrinos can be achieved in PROSPECT at 5$\sigma$ statistical significance within two hours of on-surface reactor-on data-taking. A reactor-model independent analysis of the inverse beta decay prompt energy spectrum as a function of baseline constrains significant portions of the previously allowed sterile neutrino oscillation parameter space at 95% confidence level and disfavors the best fit of the Reactor Antineutrino Anomaly at 2.2$\sigma$ confidence level., Comment: 7 pages, 5 figures; v3: Added additional supplemental files

The Precision Reactor Oscillation and Spectrum Experiment, PROSPECT, is designed to make both a precise measurement of the antineutrino spectrum from a highly-enriched uranium reactor and to probe eV-scale sterile neutrinos by searching for neutrino oscillations over meter-long baselines. PROSPECT utilizes a segmented $^6$Li-doped liquid scintillator detector for both efficient detection of reactor antineutrinos through the inverse beta decay reaction and excellent background discrimination. PROSPECT is a movable 4-ton antineutrino detector covering distances of 7m to 13m from the High Flux Isotope Reactor core. It will probe the best-fit point of the $\bar\nu_e$ disappearance experiments at 4$\sigma$ in 1 year and the favored regions of the sterile neutrino parameter space at more than 3$\sigma$ in 3 years. PROSPECT will test the origin of spectral deviations observed in recent $\theta_{13}$ experiments, search for sterile neutrinos, and address the hypothesis of sterile neutrinos as an explanation of the reactor anomaly. This paper describes the design, construction, and commissioning of PROSPECT and reports first data characterizing the performance of the PROSPECT antineutrino detector., Comment: 30 pages, 33 figures; updated with journal revision and reference

This paper describes an investigation to determine the technical feasibility of discovering and identifying the various contexts experienced by a human performer (called an actor ) solely from a trace of time-stamped values of variables. More specifically, the goal of this research was to discover the contexts that a human actor experienced, while performing a tactical task in a simulated environment, the sequence of these contexts and their temporal duration. We refer to this process as the contextualization of the performance trace. In the process of doing this, we devised a context discovery algorithm called context partitioning and clustering (COPAC). The relevant variables that were observed in the trace were selected a priori by a human. The output of the COPAC algorithm was qualitatively compared with manual (human) contextualization of the same traces. One possible use of such automated context discovery is to help build autonomous tactical agents capable of performing the same tasks as the human actor. As such, we also quantitatively compared the results of using the COPAC-derived contexts with those obtained with human-derived contextualization in building autonomous tactical agents. Test results are described and discussed.

The Precision Reactor Oscillation and Spectrum Experiment, PROSPECT, is designed to make a precise measurement of the antineutrino spectrum from a highly-enriched uranium reactor and probe eV-scale sterile neutrinos by searching for neutrino oscillations over meter-long distances. PROSPECT is conceived as a 2-phase experiment utilizing segmented $^6$Li-doped liquid scintillator detectors for both efficient detection of reactor antineutrinos through the inverse beta decay reaction and excellent background discrimination. PROSPECT Phase I consists of a movable 3-ton antineutrino detector at distances of 7 - 12 m from the reactor core. It will probe the best-fit point of the $\nu_e$ disappearance experiments at 4$\sigma$ in 1 year and the favored region of the sterile neutrino parameter space at $>$3$\sigma$ in 3 years. With a second antineutrino detector at 15 - 19 m from the reactor, Phase II of PROSPECT can probe the entire allowed parameter space below 10 eV$^{2}$ at 5$\sigma$ in 3 additional years. The measurement of the reactor antineutrino spectrum and the search for short-baseline oscillations with PROSPECT will test the origin of the spectral deviations observed in recent $\theta_{13}$ experiments, search for sterile neutrinos, and conclusively address the hypothesis of sterile neutrinos as an explanation of the reactor anomaly., Comment: 21 pages, 21 figures

Resume Les triptans sont des traitements efficaces pour les crises migraineuses. Les effets indesirables les plus frequents sont : une sensation d’oppression thoracique, des vertiges, des bouffees de chaleur. Cliniquement, les repercussions sur l’artere coronaire sont exceptionnelles ainsi que les manifestations allergiques avec ces produits. Deux observations d’urticaire ont ete rapportees : la premiere avec le sumatriptan, la seconde avec le naratriptan et l’eletriptan. Les prick-tests avec la solution de sumatriptan sont positifs. Six prick-tests, pratiques sur des patients sains et cinq patients migraineux traites par des triptans, mais ne presentant pas d’allergie a ces produits, sont negatifs. En conclusion, la reaction croisee est demontree entre les triptans, en accord avec leurs structures chimiques. Aucune reaction croisee n’a ete observee avec les derives de l’ergot de seigle et les triptans.

Description of the transfusion practice and its specificities in a geriatric unit.Prospective descriptive study realized by a single consultant.patients admitted in the unit between 01/10/2011 and 31/01/2012 with hemoglobin level below 10 g/dL.Eighty-one patients: 87.7-year-old±5.6, ADL 2.1±1.9. CIRS 15.5±3.9. Forty-five (55.5%) of the patients received blood transfusion. Cause of admittance: anemia for 9% of patients. The etiology of anemia was multifactorial in the majority of cases. Admission hemoglobin rate: 9.1 g/dL±1.1 in transfused group versus 9.6 g/dL±0.5 for non-transfused patients. The clinical signs of anemia were asthenia (98.8%), impact on everyday activities (91.4%), respiratory distress (60.5%), stability disturbances and falls (38.3%), confusion (32.1%), hemodynamic disorders (29.6%). The increase of hemoglobin rate was 1.45 g/dL in the transfused group versus 0.3 g/dL for the non-transfused patients. A side effect was observed in 2 transfused patients (4.4%).Transfusion decision criteria are rarely studied in geriatrics. The clinical signs of anemia include the classical hemodynamic disorders, cardio-respiratory and more specific of the elderly patients as confusion, majoring of cognitive decline and falls. The transfusion threshold (1.4 g/dL per 1 RBC unit) seems higher than in the overall transfused patients. Transfusion remains the fastest way to correct anemia but exposes to circulatory overload.

We investigated in conscious rats the characteristics and modes of action of CO2 on thermoregulation and ventilatory control during cold stress. In a group of 10 rats studied intact and after carotid body denervation, measurements of metabolic rate (VO2), ventilation (V), shivering, and colonic temperature (Tc) were made at controlled ambient temperatures (Ta) of 25, 20, 15, 10, and 5 degrees C. Animals were exposed on different days to 1) normoxia, 2) normoxia and 4% CO2, 3) 12% hypoxia, or 4) 10.8% hypoxia and 4% CO2. The following results were obtained. 1) During CO2 exposure in normoxia or hypoxia, VO2 is increased at Ta of 25 degrees C and decreased for lower Ta. These effects are partly mediated by carotid body afferents. 2) Shivering and nonshivering thermogenesis and therefore Tc regulation are affected by CO2 exposure as shown by relationships between VO2-Tc and VO2-shivering intensity. 3) V is controlled by PO2 and PCO2 directly through their peripheral and central actions but also indirectly through their effects on VO2. Our conclusions are as follows. 1) Control of Tc is markedly dependent on PCO2 level. Carotid body afferents play a role, but direct central effects acting on the different sources of thermogenesis and possibly on thermolysis are most prominent. 2) As far as control of V is concerned, during hypercapnia in normoxia or hypoxia, several analogies may be formed between exposure to cold and muscular exercise, both of which increase VO2 and V, suggesting common integrative mechanisms at the central nervous system level.

Today NAND Flash memory is used for data and code storage in digital cameras, USB devices, cell phones, camcorders, and solid-state disk drives. Figure 13.6.1 shows the memory-density trend since 2003. To satisfy the market demand for lower cost per bit and higher density nonvolatile memory, in addition to technology scaling, 2b/cell MLC technology was introduced. Recently, MLC NAND flash memories with more than 2b/cell [1,2] have been reported.

After a brief review of the main characteristics required by a DCS1800 (PCN) transmitter, the paper presents the design of a fast feedback control system used for the output power levelling of a DCS1800 base station transmitter. The design is presented along with a method for applying EEsof LIBRA software to simulate the circuit's performance and optimize its design. Calculated and measured results are given.

Resume Les systemes electrochimiques a deux electrons, en particulier ceux du type M 2+ /M ou M represente un metal et M 2+ le cation correspondant presentent souvent des potentiels normaux E 1 0 pour le couple M 2+ /M + et E 2 0 pour le couple M + /M dans l'ordre inverse de celui des degres d'oxydation, soit E 1 0 E 2 0 . Dans ce cas E 1 0 et E 2 0 ne peuvent etre determines par une simple mesure potentiometrique. On propose ici une methode electrochimique de determination de tels potentiels normaux inverses et on l'applique aux couples Cu 2+ /Cu + et Cu + /Cu 0 dans l'eau et le methanol.

The causes frequently ascribed to coarctation of the abdominal aorta include atherosclerosis, trauma, inflammatory aortitis, and extrinsic compression. We present a case of coarctation of the abdominal aorta with stenosis of the left renal artery due to fibrodysplasia in a 35-year-old woman, hospitalized for treatment of intermittent claudication and hypertension. This coarctation was resected and end-to-end anastomosis with reimplantation of the left renal artery was performed. Results of an anatomopathologic examination of the resected aortic specimen and the trunk of the left renal artery revealed typical lesions of fibromuscular dysplasia. The specific features of lesions in this case were compared with those from the literature.