Since the implementation of post-Soviet economic reforms, remittances have had a strong influence on the Cuban economy and society. While economic and social influences of remittances from permanent ...migration have been examined, the same cannot be said of remittances from temporary migration. As part of an expansion of professional service exports over the past decade, tens of thousands of Cuban professionals (internationalistas) have worked abroad, remitting their earnings and often returning with substantial savings and a broadened global perspective. The expansion of professional service exports across more than 65 countries in the global south has extended the influence of remittances far beyond Miami and the USA. Using first-hand accounts of returned internationalistas interviewed in Havana in 2010 and 2011, this article explores the socio-economic influences of the remittances from Cuban internationalism.
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DOBA, IZUM, KILJ, NUK, ODKLJ, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
The High Luminosity Upgrade of the LHC will require the replacement of the Inner Detector of ATLAS with the Inner Tracker (ITk) in order to cope with higher radiation levels and higher track ...densities. Prototype silicon strip detector modules are currently developed and their performance is studied in both particle test beams and X-ray beams. In previous test beam measurements of prototype modules, the response of silicon sensors has been studied in detailed scans across individual sensor strips. These scans found instances of sensor strips collecting charge across areas on the sensor deviating from the geometrical width of a sensor strip. The variations have been linked to local features of the sensor architecture. This paper presents results of detailed sensor measurements in both X-ray and particle beams investigating the impact of sensor features (metal pads and p-stops) on the sensor strip response.
The use of complimentary metal-oxide-semiconductor (CMOS) active pixel sensors (APS) in scientific applications is becoming increasingly widespread and as a result, attempts to quantify their ...absolute performance via the conversion gain parameter K(epsiv_/DN) are now common. The inherent non- linearity of CMOS APS response means that the gold standard "mean-variance" and "photon-transfer" methods for establishing sensor conversion gain cannot automatically be used. Recently, two alternative methods have been proposed for deriving the conversion gain of APS. These methods appear to produce good results but have yet to be directly compared using results from a single sensor. This paper uses a single data set from a prototype APS to provide an absolute comparison of the performance of these nonlinear methods with respect to each other, and to standard linear methods. It also proposes a measurement procedure to enable evaluation of any APS. The prototype APS "Vanilla" produced by the RC-UK MI-3 consortium was illuminated uniformly at 65 intensity levels between dark and saturation. Results for Vanilla from linear methods substantially overestimate the sensor full well capacity (p = 0.003) to be (94.1 plusmn 1.4) X 10 3 e - and (91.2 plusmn 1.4) x 10 3 e - , respectively, when compared to nonlinear analysis methods. They also slightly underestimate the sensor read noise (p = 0.016) to be 51.8 plusmn 0.7e_ and 52.3 plusmn 0.7e~, respectively. The results obtained from both nonlinear estimation (NLE) and nonlinear compensation (NLC) are in good agreement, predicting read noise of54.8plusmn0.3e - and 55.4 plusmn 0.2e - and full well capacity of (72.0 plusmn 0.3) x 10 3 e - and (72.6 plusmn 0.3) X 10 3 e - , respectively. Results indicate that nonlinear analysis should be performed for APSs.
Radiation-tolerant n-in-p planar pixel sensors have been under development in cooperation with Hamamatsu Photonics K.K. (HPK). This is geared towards applications in high-radiation environments, such ...as for the future Inner Tracker (ITk) placed in the innermost part of the ATLAS detector in the high luminosity LHC (HL-LHC) experiment. Prototypes of those sensors have been produced, irradiated, and evaluated over the last few years. In the previous studies, it was reported that significant drops in the detection efficiency were observed after irradiation, especially under bias structures. The bias structures are made up of poly-Si or Al bias rails and poly-Si bias resistors. The structure is implemented on the sensors to allow quality checks to be performed before the bump-bonding process, and to ensure that charge generated in floating pixels due to non-contacting or missing bump-bonds is dumped in a controlled way in order to avoid noise. To minimize the efficiency drop, several new pixel structures have been designed with bias rails and bias resistors relocated. Several test beams have been carried out to evaluate the drops in the detection efficiency of the new sensor structures after irradiation. Newly developed sensor modules were irradiated with proton-beams at the Cyclotron and Radio-Isotope Center (CYRIC) in Tohoku University to see the effect of sensor-bulk damage and surface charge-up. An irradiation with γ-rays was also carried out at Takasaki Advanced Radiation Research Center, with the goal of decoupling the effect of surface charge-up from that of bulk damage. Those irradiated sensors have been evaluated with particle beams at DESY and CERN. Comparison between different sensor structures confirmed significant improvements in minimizing efficiency loss under the bias structures after irradiation. The results from γ-irradiation also enabled cross-checking the results of a semiconductor technology simulation program (TCAD).
•The efficiency drop was largely suppressed in new pixel designs, especially in the Type10 sensor.•Among the offset structures, large offset structure showed least efficiency drop.•The effect of the surface damage is remarkably smaller than that of the bulk damage.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UL, UM, UPCLJ, UPUK, ZRSKP
Objectives The aim of this study was to evaluate the association between calculated creatinine clearance (CCC)-based contrast dose and renal complications in patients undergoing percutaneous coronary ...interventions (PCI). Background Excess volumes of contrast media are associated with renal complications in patients undergoing cardiac procedures. Because contrast media are excreted by the kidney, we hypothesized that a dose estimation on the basis of CCC would provide a simple strategy to define a safe dose of contrast media. Methods We assessed the association between CCC-based contrast dose and the risk of contrast-induced nephropathy (CIN) and need for in-hospital dialysis in 58,957 patients undergoing PCI and enrolled in the BMC2 (Blue Cross Blue Shield of Michigan Cardiovascular Consortium) registry from 2007 to 2008. Patients receiving dialysis at the time of the procedure were excluded. Results The risk of CIN and nephropathy requiring dialysis (NRD) was directly associated with increasing contrast volume adjusted for renal function. The risk for CIN and NRD approached significance when the ratio of contrast dose/CCC exceeded 2 (adjusted odds ratio OR for CIN: 1.16, 95% confidence interval CI: 0.98 to 1.37, adjusted OR for NRD: 1.72, 95% CI: 0.9 to 3.27) and was dramatically elevated in patients exceeding a contrast to CCC ratio of 3 (adjusted OR for CIN: 1.46, 95% CI: 1.27 to 1.66, adjusted OR for NRD: 1.89, 95% CI: 1.21 to 2.94). Conclusions Our study supports the need for minimizing contrast dose in patients with renal dysfunction. A contrast dose on the basis of estimated renal function with a planned contrast volume restricted to less than thrice and preferably twice the CCC might be valuable in reducing the risk of CIN and NRD.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
Wide bandgap semiconductor detectors for harsh radiation environments Grant, J.; Cunningham, W.; Blue, A. ...
Nuclear instruments & methods in physics research. Section A, Accelerators, spectrometers, detectors and associated equipment,
07/2005, Volume:
546, Issue:
1
Journal Article
Peer reviewed
In this work two wide bandgap materials, silicon carbide (SiC) and gallium nitride (GaN), were investigated for their performance in harsh radiation environments. Schottky devices were fabricated on ...vanadium doped SiC (V-SiC), Okmetic semi insulating (SI) non-vanadium doped SiC, SI GaN grown by MOCVD (metal organic chemical vapour deposition) and bulk GaN. Completed devices were electrically characterised and the CCE (charge collection efficiency) calculated from pulse height spectra of
241Am
α
particles. SI GaN samples were irradiated with estimated neutron fluences of up to
10
16
n
/
cm
2
(Ljubljana), proton fluences of
10
16
p
/
cm
2
(CERN), and a dose of 600
Mrad of 10
keV X-rays (ICSTM, London). V-SiC samples were irradiated up to
5
×
10
14
π
/
cm
2
using 300
MeV/c pions (PSI). Electrical characterisation and CCE calculations were repeated after irradiation to observe changes in properties caused by radiation induced damage.
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Access to an ultra-wide bore (105
mm) 21.1
T magnet makes possible numerous advances in NMR spectroscopy and MR imaging, as well as novel applications. This magnet was developed, designed, ...manufactured and tested at the National High Magnetic Field Laboratory and on July 21, 2004 it was energized to 21.1
T. Commercial and unique homebuilt probes, along with a standard commercial NMR console have been installed and tested with many science applications to develop this spectrometer as a user facility. Solution NMR of membrane proteins with enhanced resolution, new pulse sequences for solid state NMR taking advantage of narrowed proton linewidths, and enhanced spatial resolution and contrast leading to improved animal imaging have been documented. In addition, it is demonstrated that spectroscopy of single site
17O labeled macromolecules in a hydrated lipid bilayer environment can be recorded in a remarkably short period of time.
17O spectra of aligned samples show the potential for using this data for orientational restraints and for characterizing unique details of cation binding properties to ion channels. The success of this NHMFL magnet illustrates the potential for using a similar magnet design as an outsert for high temperature superconducting insert coils to achieve an NMR magnet with a field >25
T.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UL, UM, UPCLJ, UPUK
The ATLAS pixel detector for the HL-LHC requires the development of large area pixel modules that can withstand doses up to 1016 1MeVneqcm−2. The area of the pixel detector system will be over 5m2 ...and as such low cost, large area modules are required. The development of a quad module based on 4 FE-I4 readout integrated chips (ROIC) will be discussed. The FE-I4 ROIC is a large area chip and the yield of the flip-chip process to form an assembly is discussed for single chip assemblies. The readout of the quad module for laboratory tests will be reported.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UL, UM, UPCLJ, UPUK
Aid efforts are often short-term, do not lay the groundwork for long-term capacity building, and no G8 nation has fulfilled its commitment to dedicate 0.07 per cent of its GDP to foreign aid. ...aid ...efforts abroad are often positioned as furthering the interests of the donor nation. Cuban internationalism makes the same lofty attempts to address world poverty and it facilitates strong international relations, but it does so through the guise of cooperation that does not seek direct interference in another sovereign nation's approach to governance and does not attempt to develop long-term structural placement within another country. ...Blue's article comes down to the brass tacks of remuneration.
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The planned HL-LHC (High Luminosity LHC) in 2025 is being designed to maximise the physics potential through a sizable increase in the luminosity up to 6middot10 super(34) cm super(-2) s super(-1). A ...consequence of this increased luminosity is the expected radiation damage at 3000 fb super(-1) after ten years of operation, requiring the tracking detectors to withstand fluences to over 1middot10 super(16) 1 MeV n sub(eq)/cm super(2). In order to cope with the consequent increased readout rates, a complete re-design of the current ATLAS Inner Detector (ID) is being developed as the Inner Tracker (ITk). Two proposed detectors for the ATLAS strip tracker region of the ITk were characterized at the Diamond Light Source with a 3 mum FWHM 15 keV micro focused X-ray beam. The devices under test were a 320 mum thick silicon stereo (Barrel) ATLAS12 strip mini sensor wire bonded to a 130 nm CMOS binary readout chip (ABC130) and a 320 mum thick full size radial (end-cap) strip sensor - utilizing bi-metal readout layers - wire bonded to 250 nm CMOS binary readout chips (ABCN-25). A resolution better than the inter strip pitch of the 74.5 mum strips was achieved for both detectors. The effect of the p-stop diffusion layers between strips was investigated in detail for the wire bond pad regions. Inter strip charge collection measurements indicate that the effective width of the strip on the silicon sensors is determined by p-stop regions between the strips rather than the strip pitch.
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