Self-stabilizing Numerical Iterative Computation

Many challenging tasks in sensor networks, including sensor calibration, ranking of nodes, monitoring, event region detection, collaborative filtering, collaborative signal processing, {\em etc.}, can be formulated as a problem of solving a linear system of equations. Several recent works propose different distributed algorithms for solving these problems, usually by using linear iterative numerical methods. In this work, we extend the settings of the above approaches, by adding another dimension to the problem. Specifically, we are interested in {\em self-stabilizing} algorithms, that continuously run and converge to a solution from any initial state. This aspect of the problem is highly important due to the dynamic nature of the network and the frequent changes in the measured environment. In this paper, we link together algorithms from two different domains. On the one hand, we use the rich linear algebra literature of linear iterative methods for solving systems of linear equations, which are naturally distributed with rapid convergence properties. On the other hand, we are interested in self-stabilizing algorithms, where the input to the computation is constantly changing, and we would like the algorithms to converge from any initial state. We propose a simple novel method called \syncAlg as a self-stabilizing variant of the linear iterative methods. We prove that under mild conditions the self-stabilizing algorithm converges to a desired result. We further extend these results to handle the asynchronous case. As a case study, we discuss the sensor calibration problem and provide simulation results to support the applicability of our approach

Towards realistic laparoscopic image generation using image-domain translation

Background and ObjectivesOver the last decade, Deep Learning (DL) has revolutionized data analysis in many areas, including medical imaging. However, there is a bottleneck in the advancement of DL in the surgery field, which can be seen in a shortage of large-scale data, which in turn may be attributed to the lack of a structured and standardized methodology for storing and analyzing surgical images in clinical centres. Furthermore, accurate annotations manually added are expensive and time consuming. A great help can come from the synthesis of artificial images; in this context, in the latest years, the use of Generative Adversarial Neural Networks (GANs) achieved promising results in obtaining photo-realistic images. MethodsIn this study, a method for Minimally Invasive Surgery (MIS) image synthesis is proposed. To this aim, the generative adversarial network pix2pix is trained to generate paired annotated MIS images by transforming rough segmentation of surgical instruments and tissues into realistic images. An additional regularization term was added to the original optimization problem, in order to enhance realism of surgical tools with respect to the background. Results Quantitative and qualitative (i.e., human-based) evaluations of generated images have been carried out in order to assess the effectiveness of the method. ConclusionsExperimental results show that the proposed method is actually able to translate MIS segmentations to realistic MIS images, which can in turn be used to augment existing data sets and help at overcoming the lack of useful images; this allows physicians and algorithms to take advantage from new annotated instances for their training

Ammonium formate-Pd/C as a new reducing system for 1,2,4-oxadiazoles. Synthesis of guanidine derivatives and reductive rearrangement to quinazolin-4-ones with potential anti-diabetic activity

1,2,4-Oxadiazole is a heterocycle with wide reactivity and many useful applications. The reactive O-N bond is usually reduced using molecular hydrogen to obtain amidine derivatives. NH4 CO2 H-Pd/C is here demonstrated as a new system for the O-N reduction, allowing us to obtain differently substituted acylamidine, acylguanidine and diacylguanidine derivatives. The proposed system is also effective for the achievement of a reductive rearrangement of 5-(2′-aminophenyl)-1,2,4-oxadiazoles into 1-alkylquinazolin-4(1H)-ones. The alkaloid glycosine was also obtained with this method. The obtained compounds were preliminarily tested for their biological activity in terms of their cytotoxicity, induced oxidative stress, α-glucosidase and DPP4 inhibition, showing potential application as anti-diabetics

Preliminary engineering assessment of alternative magnetic divertor configurations for EU-DEMO

One of the main challenges in the roadmap to the realization of fusion energy is to develop a heat and power exhaust system able to withstand the large loads expected in the divertor of a fusion power plant. The challenge of reducing the heat load on the divertor targets is addressed, within the mission 2 \u2018Heat-exhaust systems\u2019, through the investigation of divertor configurations alternative to the standard Single Null (SN), such as the Snowflake (SF), Double Null (DN), X and Super-X (SX) divertors. This paper focuses on a preliminary engineering assessment of the alternative configurations proposed for the EU DEMO reactor. Starting from the description of the optimized plasma shape developed for each configuration, the 3D geometrical description of the Magnet System and of the main Mechanical Structures (Vacuum Vessel and in-vessel components) is presented. Based on the 3D geometry, the compatibility of the location and dimensions of ports with Remote Maintenance needs is discussed and possible design optimizations are proposed both for the Magnets system and the mechanical structures design. Finally, the various configurations are compared with regard to the engineering and feasibility aspects

GH therapy in adult GH deficiency: a review of treatment schedules and the evidence for low starting doses.

Recombinant human growth hormone (GH) has been licensed for use in adult patients with GH deficiency (GHD) for over 15 years. Early weight- and surface area-based dosing regimens were effective but resulted in supraphysiological levels of insulin-like growth factor-I (IGF-I) and increased incidence of side effects. Current practice has moved towards individualized regimens, starting with low GH doses and gradually titrating the dose according to the level of serum IGF-I to achieve an optimal dose. Here we present the evidence supporting the dosing recommendations of current guidelines and consider factors affecting dose responsiveness and parameters of treatment response. The published data discussed here lend support for the use of low GH dosing regimens in adult GHD. The range of doses defined as 'low dose' in the studies discussed here (~1-4 mg/week) is in accordance with those recommended in current guidelines and encompasses the dose range recommended by product labels

Obesity and bone loss at menopause: The role of sclerostin

Background. Peripheral fat tissue is known to positively influence bone health. However, evidence exists that the risk of non-vertebral fractures can be increased in postmenopausal women with obesity as compared to healthy controls. The role of sclerostin, the SOST gene protein product, and body composition in this condition is unknown. Methods. We studied 28 severely obese premenopausal (age, 44.7 \ub1 3.9 years; BMI, 46.0 \ub1 4.2 kg/m2 ) and 28 BMI-matched post-menopausal women (age, 55.5 \ub1 3.8 years; BMI, 46.1 \ub1 4.8 kg/m2 ) thorough analysis of bone density (BMD) and body composition by dual X-ray absorptiometry (DXA), bone turnover markers, sclerostin serum concentration, glucose metabolism, and a panel of hormones relating to bone health. Results. Postmenopausal women harbored increased levels of the bone turnover markers CTX and NTX, while sclerostin levels were non-significantly higher as compared to premenopausal women. There were no differences in somatotroph, thyroid and adrenal hormone across menopause. Values of lumbar spine BMD were comparable between groups. By contrast, menopause was associated with lower BMD values at the hip (p < 0.001), femoral neck (p < 0.0001), and total skeleton (p < 0.005). In multivariate regression analysis, sclerostin was the strongest predictor of lumbar spine BMD (p < 0.01), while menopausal status significantly predicted BMD at total hip (p < 0.01), femoral neck (p < 0.001) and total body (p < 0.05). Finally, lean body mass emerged as the strongest predictor of total body BMD (p < 0.01). Conclusions. Our findings suggest a protective effect of obesity on lumbar spine and total body BMD at menopause possibly through mechanisms relating to lean body mass. Given the mild difference in sclerostin levels between pre-and postmenopausal women, its potential actions in obesity require further investigation

Synthesis of oxazolidinones from N-aryl-carbamate and epichlorohydrin under mild conditions

The reaction conditions for an enantiospecific synthesis of various N-aryl-oxazolidinones from N-aryl-carbamates and (R) or (S) epichlorohydrin were optimized. The N-aryl-oxazolidinones were applied to the synthesis of compounds of biological interest such as DuP 721, toloxatone and a linezolid analogue

Sudden cardiac death after robbery: Homicide or natural death?

Tako-Tsubo is one of a number of rare acquired cardiomyopathies that are characterized by left ventricular dyskinesia and symptomatology typical of acute myocardial infarction (AMI). The most important feature is that the clinical features are triggered by a severe physical or emotional stress. The authors describe the story of a woman, who was brutally assaulted by two men during a house robbery and died from sudden heart failure 8 hours later, after being taken to hospital. External examination revealed no macroscopic alteration of the inner organs, whereas microscopy showed contraction bands with myocardial necrosis, subendocardial and interstitial neutrophil infiltration and fibrosis. These findings were consistent with death due to stress cardiomyopathy even in the absence of previous heart disease. The robbers were convicted of homicide and sentenced to eighteen years in prison

Monitoring Partially Synchronous Distributed Systems using SMT Solvers

In this paper, we discuss the feasibility of monitoring partially synchronous distributed systems to detect latent bugs, i.e., errors caused by concurrency and race conditions among concurrent processes. We present a monitoring framework where we model both system constraints and latent bugs as Satisfiability Modulo Theories (SMT) formulas, and we detect the presence of latent bugs using an SMT solver. We demonstrate the feasibility of our framework using both synthetic applications where latent bugs occur at any time with random probability and an application involving exclusive access to a shared resource with a subtle timing bug. We illustrate how the time required for verification is affected by parameters such as communication frequency, latency, and clock skew. Our results show that our framework can be used for real-life applications, and because our framework uses SMT solvers, the range of appropriate applications will increase as these solvers become more efficient over time.Comment: Technical Report corresponding to the paper accepted at Runtime Verification (RV) 201

Past&Present at Tarchna&Tarquinia: a flexible approach to make visible the invisible

This contribution falls within the topic of the “development of guidelines and best practices” and deals with the study case of the ancient Etruscan city of Tarchna (Tarquinia, central Italy). The “Tarquinia Project” started here in 1982 with the investigations carried out by the Università degli Studi di Milano in two sacred areas and along the fortifications. The Project was endowed since its beginnings with the collaboration of several experts in disciplines other than Archaeology which number has increased in the past years. Their aim is to find out as much as possible about the material aspects of Archaeology to decode their relationship with the invisibility of ancient life. This contribution aims at presenting our approach addressed to put scholars in the condition to handle data according to their own procedures, within the same environment, through an ecosystem of benchmarks and references in ways close to the individual practices, supported by ICTs. This is meant to avoid the use of predetermined terminologies and categories, enhancing the proper methods of every single discipline involved in a multidisciplinary environment, beyond the current work of every individual scholar. We propose a radical change of perspective, starting from the collection of raw data in several fields (material aspects of Archaeology, Geoarchaeology, Architecture, Topography) to grasp the underlining model, thanks to the assessment of recurrent associations among different categories of evidence, instead of starting from preconceived theoretic models and using data to confirm them. Distinct small, medium and large scale investigation methods are integrated for the first time to produce a significant interdisciplinary cognitive tool to shift from the materiality of the leftovers of Ancient Past, to its integrity, to what lies behind at a metaphysical level and is, therefore, invisible to us. This is related to the materiality of rituals, based on the recurrence of cultic practices in the above-mentioned sacred areas, whose gestures might also be revealed by sediments and organic remains, in addition to other archaeological and epigraphic issues. Tarquinia strongly challenges researchers to be open to unconventional and unexploited issues due to the complexity of the site. It is the ideal place to create awareness among the general public about the results of Archaeological research and to disseminate and make visible its acquirements, according to the European Charter for Researchers. The support of Environmental Psychologists helps to ensuring outreach entails initiatives directed to the local population, in order to introduce them to an equilibrated connection between their invisible Past and the local present culture. In this framework students from high school are involved in the Archaeological field activities, since 2012. Our best practices are therefore addressed to give back to the ancient Etruscan city its value of prominent cultural and natural landmark in the Past, to make it possible for the modern community to assess it in the same way. According to current theories of “place identity” and "place attachment" the modern community is in the condition to feeling and experiencing the continuity between past, present and future