A reconfigurable CPW bow-tie antenna using an integrated ferroelectric thin film varactor

A novel printed antenna with a frequency reconfigurable feed network is presented. The antenna consists of a bowtie structure patch radiating element in the inner space of an annulus that is on a nongrounded substrate with a ferroelectric (FE) Barium Strontium Titanate (BST) thin film. The bowtie patch is fed by a coplanar waveguide (CPW) transmission line that also includes a CPW-based BST shunt varactor. Reconfiguration of the compact 8 mm × 8 mm system has been demonstrated by shifting the antenna system’s operating frequency 500 MHz in the 7–9 GHz band by applying a DC voltage bias

A major electronics upgrade for the H.E.S.S. Cherenkov telescopes 1-4

The High Energy Stereoscopic System (H.E.S.S.) is an array of imaging atmospheric Cherenkov telescopes (IACTs) located in the Khomas Highland in Namibia. It consists of four 12-m telescopes (CT1-4), which started operations in 2003, and a 28-m diameter one (CT5), which was brought online in 2012. It is the only IACT system featuring telescopes of different sizes, which provides sensitivity for gamma rays across a very wide energy range, from ~30 GeV up to ~100 TeV. Since the camera electronics of CT1-4 are much older than the one of CT5, an upgrade is being carried out; first deployment was in 2015, full operation is planned for 2016. The goals of this upgrade are threefold: reducing the dead time of the cameras, improving the overall performance of the array and reducing the system failure rate related to aging. Upon completion, the upgrade will assure the continuous operation of H.E.S.S. at its full sensitivity until and possibly beyond the advent of CTA. In the design of the new components, several CTA concepts and technologies were used and are thus being evaluated in the field: The upgraded read-out electronics is based on the NECTAR readout chips; the new camera front- and back-end control subsystems are based on an FPGA and an embedded ARM computer; the communication between subsystems is based on standard Ethernet technologies. These hardware solutions offer good performance, robustness and flexibility. The design of the new cameras is reported here.Comment: Proceedings of the 34th International Cosmic Ray Conference, 30 July- 6 August, 2015, The Hague, The Netherland

The Effects of Reputation and Ethics on Budgetary Slack

This experimental study tests the effects on budgetary slack of two potential controls for opportunistic self-interestóreputation and ethics. I manipulate the level of information asymmetry between the subordinate and the superior regarding productive capability and measure the subordinateís reputation and ethical concerns regarding budgetary slack. In this setting, I examine how information asymmetry affects reputation and ethical concerns, and test the effects of these concerns on budgetary slack. Consistent with prior findings, subordinates restrict the slack in their budgets to well below the maximum under a slackinducing pay scheme, even after five periods of experience. Budgetary slack is negatively associated with a measure of ethical responsibility from a pre-experiment personality questionnaire as well as reputation and ethical concerns expressed in an exit questionnaire. Subordinates express lower reputation concerns as information asymmetry regarding productive capability increases, thereby reducing the superiorís ability to monitor the slack in their budget. Ethical concerns, however, are not diminished with increases in information asymmetry. These results suggest that reputation is a socially mediated control, whereas ethics is an internally mediated control for opportunistic self-interest

Glucose tolerance is negatively associated with circulating progenitor cell levels

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HbA1c variability as an independent correlate of nephropathy, but not retinopathy, in patients with type 2 diabetes: The renal insufficiency and cardiovascular events (RIACE) Italian Multicenter Study

OBJECTIVE: To examine the association of hemoglobin (Hb) A1c variability with microvascular complications in the large cohort of subjects with type 2 diabetes from the Renal Insufficiency And Cardiovascular Events (RIACE) Italian Multicenter Study. RESEARCH DESIGN AND METHODS: Serial (3-5) HbA1c values collected in a 2-year period before enrollment were available from 8,260 subjects from 9 centers (of 15,773 patients from 19 centers). HbA1c variability was measured as the intraindividual SD of 4.52 \ub1 0.76 values. Diabetic retinopathy (DR) was assessed by dilated funduscopy. Chronic kidney disease (CKD) was defined based on albuminuria, as measured by immunonephelometry or immunoturbidimetry, and estimated glomerular filtration rate (eGFR) was calculated from serum creatinine. RESULTS: Median and interquartile range of average HbA1c (HbA1c-MEAN) and HbA1c-SD were 7.57% (6.86-8.38) and 0.46% (0.29-0.74), respectively. The highest prevalence of microalbuminuria, macroalbuminuria, reduced eGFR, albuminuric CKD phenotypes, and advanced DR was observed when both HbA1c parameters were above the median and the lowest when both were below the median. Logistic regression analyses showed that HbA1c-SD adds to HbA1c-MEAN as an independent correlate of microalbuminuria and stages 1-2 CKD and is an independent predictor of macroalbuminuria, reduced eGFR, and stages 3-5 albuminuric CKD, whereas HbA1c-MEAN is not. The opposite was found for DR, whereas neither HbA1c-MEAN nor HbA1c-SD affected nonalbuminuric CKD. CONCLUSIONS: In patients with type 2 diabetes, HbA1c variability affects (albuminuric) CKD more than average HbA1c, whereas only the latter parameter affects DR, thus suggesting a variable effect of these measures on microvascular complications

Is There Evidence That Oral Hypoglycemic Agents Reduce Cardiovascular Morbidity/Mortality? Yes

Athough type 2 diabetes is a heterogeneous condition encompassing multiple metabolic and vascular alterations, it can be easily described as a disease characterized by chronic hyperglycemia and increased cardiovascular (CV) risk. Hyperglycemia is the diagnostic criterion for diabetes, the target for antidiabetic therapy, and, together with A1C, the marker of glycemic control. Progressive worsening of glycemic control has been described in type 2 diabetic patients irrespective of initial form of treatment, leading the U.K. Prospective Diabetes Study (UKPDS) investigators to describe such changes as the “natural history” of the disease ( 1). Still, maintaining good glycemic control is crucial, since it is associated with marked reduction in the risk of developing retinopathy, nephropathy, and neuropathy in both type 1 ( 2) and type 2 diabetic patients ( 1). But it is CV disease that worsens long-term prognosis in type 2 diabetes ( 3), to the point that diabetes has been proposed as a CV risk equivalent owed to the observation that 10-year risk for major coronary events approximates the risk in CHD in patients without diabetes with previous CV events ( 4), increased case fatality rate after myocardial infarction, and worse overall prognosis after CHD ( 5). In diabetic patients, even after correction for known CV risk factors, the incidence of myocardial infarction or stroke is two- to threefold higher than in the nondiabetic population, with a twofold increase in risk of death ( 6), suggesting that some feature of diabetes must confer excessive propensity toward CV disease. Can this feature be hyperglycemia? No better issue can be chosen for debate. From an epidemiological point of view, there is evidence that the risk of CV mortality increases with the increase of plasma glucose concentrations ( 7) and A1C values ( 8). Moreover, multiple atherogenic mechanisms have been identified that can be activated by hyperglycemia ( 9)

Dual task interference during gait in patients with unilateral vestibular disorders

<p>Abstract</p> <p>Background</p> <p>Vestibular patients show slower and unsteady gait; they have also been shown to need greater cognitive resources when carrying out balance and cognitive dual tasks (DT). This study investigated DT interference during gait in a middle-aged group of subjects with dizziness and unsteadiness after unilateral vestibular neuronitis and in a healthy control group.</p> <p>Methods</p> <p>Fourteen individuals with subacute unilateral vestibular impairment after neuronitis and seventeen healthy subjects performed gait and cognitive tasks in single and DT conditions. A statistical gait analysis system was used and spatio-temporal parameters were considered. The cognitive task, consisting of backward counting by three, was tape recorded and the number of right figures was then calculated.</p> <p>Results</p> <p>Both patients and controls showed a more conservative gait during DT and between groups significant differences were not found. A significant decrease in cognitive performance during DT was found only in the vestibular group.</p> <p>Conclusions</p> <p>Results suggest that less attentional resources are available during gait in vestibular patients compared to controls, and that a priority is given in keeping up the motor task to the detriment of a decrease of the cognitive performance during DT.</p