Development of an evaluation technique for strapdown guidance systems Interim scientific report

Evaluation technique to measure performance of strapdown guidance systems designed for unmanned interplanetary mission

SEASAT B orbit synthesis

Addition were made to Battelle's Interactive Graphics Orbit Selection (IGOS) program; IGOS was exercised via telephone lines from JPL, and candidate SEASAT orbits were analyzed by Battelle. The additions to the program enable clear understanding of the implications of a specific orbit to the diverse desires of the SEASAT user community

Event-driven visual attention for the humanoid robot iCub.

Fast reaction to sudden and potentially interesting stimuli is a crucial feature for safe and reliable interaction with the environment. Here we present a biologically inspired attention system developed for the humanoid robot iCub. It is based on input from unconventional event-driven vision sensors and an efficient computational method. The resulting system shows low-latency and fast determination of the location of the focus of attention. The performance is benchmarked against an instance of the state of the art in robotics artificial attention system used in robotics. Results show that the proposed system is two orders of magnitude faster that the benchmark in selecting a new stimulus to attend

Effectiveness evaluation of STOL transport operations

A short-takeoff and landing (STOL) systems simulation model has been developed and implemented in a computer code (known as STOL OPS) which permits evaluation of the operation of a STOL aircraft and its avionics in a commercial airline operating environment. STOL OPS concentrated on the avionics functions of navigation, guidance, control, communication, hazard aviodance, and systems management. External world factors influencing the operation of the STOL aircraft include each airport and its geometry, air traffic at each airport, air traffic control equipment and procedures, weather (including winds and visibility), and the flight path between each airport served by the route. The development of the STOL OPS program provides NASA a set of computer programs which can be used for detailed analysis of a STOL aircraft and its avionics and permit establishment of system requirements as a function of airline mission performance goals

Small-area deprivation index does not improve the capability of multisource comorbidity score in mortality prediction

BackgroundThe stratification of the general population according to health needs allows to provide better-tailored services. A simple score called Multisource Comorbidity Score (MCS) has been developed and validated for predicting several outcomes. The aim of this study was to evaluate whether the ability of MCS in predicting 1-year mortality improves by incorporating socioeconomic data (as measured by a deprivation index). MethodsBeneficiaries of the Italian National Health Service who in the index year (2018) were aged 50-85 years and were resident in the Sicily region for at least 2 years were identified. For each individual, the MCS was calculated according to his/her clinical profile, and the deprivation index of the census unit level of the individual's residence was collected. Frailty models were fitted to assess the relationship between the indexes (MCS and deprivation index) and 1-year mortality. Akaike information criterion and Bayesian information criterion statistics were used to compare the goodness of fit of the model that included only MCS and the model that also contained the deprivation index. The models were further compared by means of the area under the receiver operating characteristic curve (AUC). ResultsThe final cohort included 1,062,221 individuals, with a mortality rate of 15.6 deaths per 1,000 person-years. Both MCS and deprivation index were positively associated with mortality.The goodness of fit statistics of the two models were very similar. For MCS only and MCS plus deprivation index models, Akaike information criterion were 17,013 and 17,038, respectively, whereas Bayesian information criterion were 16,997 and 17,000, respectively. The AUC values were 0.78 for both models. ConclusionThe present study shows that socioeconomic features as measured by the deprivation index did not improve the capability of MCS in predicting 1-year risk of death. Future studies are needed to investigate other sources of data to enhance the risk stratification of populations

Acquired tracheoesophageal fistula repair, due to prolonged mechanical ventilation, in patient with double incomplete aortic arch

We report a case of the repair of an acquired benign tracheoesophageal fistula (TEF) after prolonged mechanical invasive ventilation. Patient had an unknown double incomplete aortic arch determining a vascular ring above trachea and esophagus. External tracheobronchial compression, caused by the vascular ring, increasing the internal tracheoesophageal walls pressure determined by endotracheal and nasogastric tubes favored an early TEF development. The fistula was repaired through an unusual left thoracotomy and vascular ring dissection. TEFs are a heterogeneous group of diseases affecting critically ill patients. Operative closure is necessary to avoid further complications related to this condition. Pre-opera-tive study is mandatory to plan an adequate surgical approach

Methylglyoxal-dependent glycative stress and deregulation of SIRT1 functional network in the ovary of PCOS mice

Advanced glycation end-products (AGEs) are involved in the pathogenesis and consequences of polycystic ovary syndrome (PCOS), a complex metabolic disorder associated with female infertility. The most powerful AGE precursor is methylglyoxal (MG), a byproduct of glycolysis, that is detoxified by the glyoxalase system. By using a PCOS mouse model induced by administration of dehydroepiandrosterone (DHEA), we investigated whether MG-dependent glycative stress contributes to ovarian PCOS phenotype and explored changes in the Sirtuin 1 (SIRT1) functional network regulating mitochondrial functions and cell survival. In addition to anovulation and reduced oocyte quality, DHEA ovaries revealed altered collagen deposition, increased vascularization, lipid droplets accumulation and altered steroidogenesis. Here we observed increased intraovarian MG-AGE levels in association with enhanced expression of receptor for AGEs (RAGEs) and deregulation of the glyoxalase system, hallmarks of glycative stress. Moreover, DHEA mice exhibited enhanced ovarian expression of SIRT1 along with increased protein levels of SIRT3 and superoxide dismutase 2 (SOD2), and decreased peroxisome proliferator-activated receptor gamma co-activator 1 alpha (PGC1 alpha), mitochondrial transcriptional factor A (mtTFA) and translocase of outer mitochondrial membrane 20 (TOMM20). Finally, the presence of autophagy protein markers and increased AMP-activated protein kinase (AMPK) suggested the involvement of SIRT1/AMPK axis in autophagy activation. Overall, present findings demonstrate that MG-dependent glycative stress is involved in ovarian dysfunctions associated to PCOS and support the hypothesis of a SIRT1-dependent adaptive response

Magnetars' Giant Flares: the case of SGR 1806-20

We first review on the peculiar characteristics of the bursting and flaring activity of the Soft Gamma-ray Repeaters and Anomalous X-ray Pulsars. We then report on the properties of the SGR 1806-20's Giant Flare occurred on 2004 December 27th, with particular interest on the pre and post flare intensity/hardness correlated variability. We show that these findings are consistent with the picture of a twisted internal magnetic field which stresses the star solid crust that finally cracks causing the giant flare (and the observed torsional oscillations). This crustal fracturing is accompanied by a simplification of the external magnetic field with a (partial) untwisting of the magnetosphere.Comment: 6 pages, 2 figures; accepted for publication in the Chinese Journal for Astronomy and Astrophysics (Vulcano conference - 2005

Simultaneous Multi-band Radio & X-ray Observations of the Galactic Center Magnetar SGR 1745−-2900

We report on multi-frequency, wideband radio observations of the Galactic Center magnetar (SGR 1745$-$2900) with the Green Bank Telescope for $\sim$100 days immediately following its initial X-ray outburst in April 2013. We made multiple simultaneous observations at 1.5, 2.0, and 8.9 GHz, allowing us to examine the magnetar's flux evolution, radio spectrum, and interstellar medium parameters (such as the dispersion measure (DM), the scattering timescale and its index). During two epochs, we have simultaneous observations from the Chandra X-ray Observatory, which permitted the absolute alignment of the radio and X-ray profiles. As with the two other radio magnetars with published alignments, the radio profile lies within the broad peak of the X-ray profile, preceding the X-ray profile maximum by $\sim$0.2 rotations. We also find that the radio spectral index $\gamma$ is significantly negative between $\sim$2 and 9 GHz; during the final $\sim$30 days of our observations $\gamma \sim -1.4$, which is typical of canonical pulsars. The radio flux has not decreased during this outburst, whereas the long-term trends in the other radio magnetars show concomitant fading of the radio and X-ray fluxes. Finally, our wideband measurements of the DMs taken in adjacent frequency bands in tandem are stochastically inconsistent with one another. Based on recent theoretical predictions, we consider the possibility that the dispersion measure is frequency-dependent. Despite having several properties in common with the other radio magnetars, such as $L_{\textrm{X,qui}}/L_{\textrm{rot}} \lesssim 1$, an increase in the radio flux during the X-ray flux decay has not been observed thus far in other systems.Comment: 15 pages, 9 figures, 3 tables; accepted to Ap