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This paper proposes a technique for estimating the computational time of programs in an actor model, which is intended to serve as a compiler target of a wide variety of actor-based programming languages. We define a compositional translation function returning cost equations, which are fed to an automatic off-the-shelf solver for obtaining the time bounds. Our approach is based on a new notion of synchronization sets, which captures possible difficult synchronization patterns between actors and helps make the analysis efficient and precise. The approach is proven to correctly over-approximate the worst computational time of an actor model of concurrent programs. Our technique is complemented by a prototype analyzer that returns upper bound of costs for the actor model. (C) 2019 Elsevier Inc. All rights reserved.

A method for assessing and mapping the wind energy potential of near- and off-shore areas by means of multi sensor satellites (i.e. the recently launched Sentinel 1) is shown in this paper and applied to a case study area in the north-west coast of the Sicily island. The presented method aims at i) preliminary identifying the best sites for wind turbine generators installation and/or ii) estimating the average wind potential in small areas (e.g. archipelagos) for energy planning purposes. Firstly, a detailed literature review of existing techniques for wind speed estimation has been carried out, considering the most traditional methods (e.g. meteorological masts), remote sensing techniques and including a thorough review on the use of Synthetic Aperture Radar (SAR) methods integrated with Geophysical Model Functions (GMFs) for wind speed retrieval. This review enables to identify CMOD5 (C Geophysical model function 5) as the best performing GMF overcoming the CMOD4 accuracy issues in high wind speed conditions. Thus, the method has been detailly described and showcased through the analysis of the case study. SAR images from the Sentinel 1 satellite have been processed by means of the Sentinel Application Platform (SNAP) software. Afterwards, the wind speed and direction have been mapped through a Geographic Information System software. Lastly, the mean wind climate has been extrapolated for a specific Region Of Interest by the Environment for Visualizing Images (ENVI) 4.8 software. Consequentially, six hot spots characterized by high-energy potential have been identified as possible sites for possible installations of wind turbine generators.

International audience; Deadlock detection in concurrent programs that create networks with arbitrary numbers of nodes is extremely complex and solutions either give imprecise answers or do not scale. To enable the analysis of such programs, (1) we define an algorithm for detecting deadlocks of a basic model featuring recursion and fresh name generation: the lam programs, and (2) we design a type system for value-passing CCS that returns lam programs. We show the soundness of the type system, and develop a type inference algorithm for it. The resulting algorithm is able to check deadlock-freedom of programs that cannot be handled by previous analyses, such as those that build unbounded networks.

Expressions are multilinear when variable occurrences are linear and products have factors using different variables. We demonstrate that multilinear expressions are either constant or have never a local minimum or a local maximum. Therefore the interval of multilinear expressions may be computed precisely studying their values at the bounds of the variables therein. We then propose a technique for the interval analysis of generic expressions that transforms them into multilinear ones and computes the interval of the latters.

The nanoκ calculus is a formalism that models biochemical systems by defining its set of reactions. We study the implementation of nanoκ into the Stochastic Pi Machine where biochemical systems are defined by regarding molecules as processes, and deriving the overall behaviour by means of communication rules. Our implementation complies with the stochastic behaviors of systems, thus allowing one to use nanoκ as an intelligible front-end for a process-oriented simulator. This study also permits to reuse, in nanoκ, the theories and tools already developed for process calculi.

Urban growth and population dynamics are among the most critical information needed for future economic development planning, natural resources allocation and environmental management. In the present work, two methods, the first based on night-time images produced by NOAA and population maps provided by Oak Ridge National Laboratory's (ORNL) LandScan, and the second one on SAR imagery, were used in order to assess the expansion of urban areas surrounding the Winam Gulf (Lake Victoria, Kenya) at different scales. In the time covered by night-time lights imagery, the study highlighted a period of constant growth rate between 2002 and 2006 and a negative trend after 2006 and 2008. This decrease may be related to two main events occurring in the study area between 2006 and 2007: the decline of the Lake Victoria level and the abnormal proliferation of the floating weeds within the Winam Gulf. Meanwhile, the urban feature extraction obtained at a different scale within a particular district from 1997 up to 2008 results in a constant growth rate. Population movements around this zone explain different dynamics that should be studied in detail in order to understand their particular roots.

Several schema languages have been recently proposed for describing XML documents. The key notion of such languages is the subschema relation which is used for type checking. We present a schema language for modelling XML documents containing channel schemas with (input and output) capabilities and we describe two subschema algorithms. The first one uses a simulation relation; the second one examines the structure of the schemas. We demonstrate the equivalence of the algorithms and we discuss their computational complexity.

A language of formal proteins, the κ-calculus, is introduced. Interactions are modeled at the domain level, bonds are represented by means of shared names, and reactions are required to satisfy a causality requirement of monotonicity.An example of a simplified signalling pathway is introduced to illustrate how standard biological events can be expressed in our protein language. A more comprehensive example, the lactose operon, is also developed, bringing some confidence in the formalism considered as a modeling language.Then a finer-grained concurrent model, the mκ-calculus, is considered, where interactions have to be at most binary. We show how to embed the coarser-grained language in the latter, a property which we call self-assembly.Finally we show how the finer-grained language can itself be encoded in π-calculus, a standard foundational language for concurrency theory.

Microdamage has been cited as an important element of trabecular bone quality and fracture risk, as materials with flaws have lower modulus and strength than equivalent undamaged materials. However, the magnitude of the effect of damage on failure properties depends on its tendency to propagate. Human femoral trabecular bone from the neck and greater trochanter was subjected to one of compressive, torsional, or combined compression and torsion. The in vivo, new, and propagating damage were then quantified in thick sections under epifluorescent microscopy. Multiaxial loading, which was intended to represent an off-axis load such as a fall or accident, caused much more damage than either simple compression or shear, and similarly caused the greatest stiffness loss. In all cases, initiation of new damage far exceeded the propagation of existing damage. This may reflect stress redistribution away from damaged trabeculae, resulting in new damage sites. However, the accumulation of new damage was positively correlated with the quantity of pre-existing damage in all loading modes, indicating that damaged bone is inherently more prone to further damage formation. Moreover, about 50% of in vivo microcracks propagated under each type of loading. Finally, damage formation was positively correlated to decreased compressive stiffness following both axial and shear loading. Taken together, these results demonstrate that damage in trabecular bone adversely affects its mechanical properties, and is indicative of bone that is more susceptible to further damage.

To determine the benefits of Lactobacillus rhamnosus GG (LGG) in an extensively hydrolyzed casein formula (EHCF) in improving hematochezia and fecal calprotectin over EHCF alone.Fecal calprotectin was compared in 30 infants with hematochezia and 4 weeks after milk elimination with that of a healthy group. We also compared fecal calprotectin and hematochezia on 26 formula-fed infants randomly assigned to EHCF with LGG (Nutramigen LGG) (EHCF + LGG) or without (Nutramigen) (EHCF - LGG) and on 4 breastfed infants whose mothers eliminated dairy.Fecal calprotectin in those with hematochezia was significantly higher than in comparisons (mean +/- SD 325.89 +/- 152.31 vs 131.97 +/- 37.98 microg/g stool, t = 6.79, P.0001). At 4 weeks, fecal calprotectin decreased to 50% of baseline but was still significantly higher than in comparisons (157.5 +/- 149.13 vs 93.72 +/- 36.65 microg/g, P = .03). Fecal calprotectin mean decrease was significantly larger among EHCF + LGG compared with EHCF - LGG (-214.5 +/- 107.93 vs -112.7 +/- 105.27 microg/g, t = 2.43, P = .02). At 4 weeks, none of the EHCF + LGG had blood in stools, and 5/14 on EHCF - LGG did (P = .002).Fecal calprotectin is elevated in infants with hematochezia and possible allergic colitis. EHCF + LGG resulted in significant improvement of hematochezia and fecal calprotectin compared with the EHCF alone.

We develop a process calculus-the [email protected] calculus-for modeling, analyzing and predicting the properties of molecular devices. The [email protected] calculus is equipped with a simple stochastic model, that we use to model and simulate the behavior of a molecular shuttle, a basic nano device currently used for building more complex systems.

We design an extension of the join calculus with class-based inheritance. Method calls, locks, and states are handled in a uniform manner, using asynchronous messages. Classes are partial message definitions that can be combined and transformed by means of operators for behavioral and synchronization inheritance. We also give a polymorphic type system that statically enforces basic safety properties. Our language and its type system are compatible with the JoCaml implementation of the join calculus.

Objective: To evaluate the family history of epilepsy in first degree relatives of probands with epilepsy. Methods: A sample of 10787 patients with epilepsy with complete information about first degree relatives (parents, siblings and offspring) was selected from the database of the Episcreen Project, the largest Italian observational study on epilepsy. Family history was assessed by: (1) prevalence estimates of epilepsy among proband's relatives, (2) modified cumulative risks (MCR), adjusted using proband's age as censoring time in life tables, (3) standardised morbidity ratios (SMR), using a sub-group of symptomatic epilepsies as control group. Results: Patients (9.1%) had a family history of epilepsy. The overall prevalence of epilepsy among first degree relatives was 2.6%. Idiopathic generalised epilepsies had the highest prevalence (5.3%). Cryptogenetic epilepsies had a lower prevalence (2.1%) than idiopathic epilepsies, but higher then symptomatic epilepsies (1.5%), both in generalised and focal forms (3.8% vs. 2.0% and 1.8% vs. 1.3%). A similar tendency was detected using MCR and SMR, with the higher values of risks/ratios for idiopathic and generalised epilepsies. Probands with idiopathic generalised epilepsies were highly concordant with respect to their relatives' type of epilepsy. Considering other strata factors, risks were higher in proband's epilepsies with an onset less then 14 years of age, while sex played no definite role in differentiating the family history. Conclusions: The Episcreen model permits a variety of stratification factors to measure family risk, including age at onset, epilepsy localisation and aetiology with a large sample of more than 10000 probands and 1065/40544 relatives affected and classified.

Here we report the purification, from Xenopus laevis oocyte nuclear extracts, of a new endoribonuclease, XendoU, that is involved in the processing of the intron-encoded box C/D U16 small nucleolar RNA (snoRNA) from its host pre-mRNA. Such an activity has never been reported before and has several uncommon features that make it quite a novel enzyme: it is poly(U)-specific, it requires Mn(2+) ions, and it produces molecules with 2'-3'-cyclic phosphate termini. Even if XendoU cleaves U-stretches, it displays some preferential cleavage on snoRNA precursor molecules. XendoU also participates in the biosynthesis of another intron-encoded snoRNA, U86, which is contained in the NOP56 gene of Xenopus laevis. A common feature of these snoRNAs is that their production is alternative to that of the mRNA, suggesting an important regulatory role for all the factors involved in the processing reaction.

The current definition of the Java bytecode verifier, as well as the proposals to formalize it, does not include any check about the structured use of locks by monitorenter and monitorexit instructions. So code is run, even if critical sections are corrupted. In this paper, we isolate a sublanguage of the Java Virtual Machine with thread creation and mutual exclusion. For this subset, we define a semantics and a formal verifier that enforces basic properties of threads and lock and unlock operations. The verifier integrates well with previous formalizations of the Java bytecode verifier. Our analysis of structured use of locks reveals the presence of bugs in the current compilers from Sun, IBM and Microsoft.

Summary Circular RNAs (circRNAs) constitute a family of transcripts with unique structures and still largely unknown functions. Their biogenesis, which proceeds via a back-splicing reaction, is fairly well characterized, whereas their role in the modulation of physiologically relevant processes is still unclear. Here we performed expression profiling of circRNAs during in vitro differentiation of murine and human myoblasts, and we identified conserved species regulated in myogenesis and altered in Duchenne muscular dystrophy. A high-content functional genomic screen allowed the study of their functional role in muscle differentiation. One of them, circ-ZNF609, resulted in specifically controlling myoblast proliferation. Circ-ZNF609 contains an open reading frame spanning from the start codon, in common with the linear transcript, and terminating at an in-frame STOP codon, created upon circularization. Circ-ZNF609 is associated with heavy polysomes, and it is translated into a protein in a splicing-dependent and cap-independent manner, providing an example of a protein-coding circRNA in eukaryotes., Graphical Abstract, Highlights • CircRNAs are conserved, abundant, and regulated in myogenesis • High-throughput phenotypic screening reveals functional circRNAs • Circ-ZNF609 regulates myoblast proliferation • Circ-ZNF609 can be translated, Legnini et al. identified circ-ZNF609, a circular RNA expressed in murine and human myoblasts, which controls myoblast proliferation. Circ-ZNF609 contains an open reading frame and is translated into a protein in a splicing-dependent/cap-independent manner. Circ-ZNF609 translation can be modulated by stress conditions.

Neutral density measurements were carried out by the microaccelerometer on board the Italian San Marco V satellite in 1988. During the final week of its existence the satellite's perigee decreased to as low as 130 km. Measured density values were compared to the corresponding CIRA '86 (MSIS '86) or to our dMSIS model values. The residuals reveal a wavy structure of different time scales. Characterising the wave amplitude by the average deviation of the residuals, its dependence on different parameters was studied. These investigations demonstrated that the wave-amplitude varies with height, local solar time and geomagnetic disturbance level. There is a particularly developed wave pattern in the average deviations below 200 km. Case studies indicated that there are sudden density decreases of 20–30 sec duration that might be in connection with plasma bubble crossings by the satellite. Altogether 261 such cases were identified and their distribution as a function of height, LST and longitude have been investigated.

Neutral density measurements by the Drag Balance Instrument (DBI) on board the Italian San Marco V satellite are made with high time resolution. These measurements permit the direct investigation of the thermospheric wave pattern variation in the equatorial zone. The investigation has been carried out not only statistically, but also through case studies. One of the interesting results is that, although the wave amplitude generally increases continuously with altitude, there are some cases when it changes abruptly. These abrupt changes can occur at different altitudes. The coupling processes such as ion drag and spatial resonance have also been studied as a function of altitude (h), local solar time (LST) and other parameters.

The design of the passive temperature control on a spacecraft is generally based on the tentative assignment of the thermo-optical parameters, on the computation of the corresponding temperatures and, then, on a correction procedure based on a locally linearized “sensitivity”. In this paper, instead of this classical approach, we try a method that, still on a linearized basis, uses the pseudo-inverse of the temperature vector to realize the wished temperature in the structure. The solution of the problem uses the definition of null space and pseudo-inverse and the matrix of the unknown is determined in such a way that the physical characteristics of the coupling radiative and conductive matrix (that means symmetry and balance) are satisfied. Other constraints shall be imposed, and at the end, when the number of unknowns is equal to the equations, the problem is solved. Due to the arbitrariness in the additional constraints needed for closing the problem, the solution obtained with this method is not unique. It is possible in any case to choose optimized solutions as, for instance, the easiest to be realized in practice.

The characterization and catalytic properties of a new molecular cluster precursor, Ti 4 O 4 [OCH(CH 3 ) 2 ] 4 {(CO) 9 Co 3 CCO 2 } 4 , denoted Ti 4 Co 12 , were studied during the vapor phase hydrogenation of 2-butenal to form the thermodynamically less favored product, 2-butenol. Pyrolysis of this precursor yields three active catalytic forms, designated LT-, HT1-, and HT2-. This catalyst shows enhanced thermal stability (up to 400°C) as compared to M 2 {(CO) 9 Co 3 CCO 2 } 4 (where M=Co, Cu, or Mo) and M 4 O{(CO) 9 Co 3 CCO 2 } 6 (where M=Zn or Co), which are stable only to 300°C. It has been found that the HT1-Ti 4 Co 12 structure provides significantly better selectivity to 2-butenol than the HT2-Ti 4 Co 12 structure. In-situ DRIFTS measurements during the decomposition of the precursor indicate the presence of COO − groups during the formation of the selective HT1-Ti 4 Co 12 form. These groups disappear at higher temperatures when the HT2-Ti 4 Co 12 catalyst is formed. We speculate that these ions are related to the high selectivity of these materials.

Lamping's optimal graph reduction technique for the λ-calculus is generalized to a new class of higher-order rewriting systems, called Interaction Systems. Interaction Systems provide a nice integration of the functional paradigm with a rich class of data structures (all inductive types), and some basic control flow constructs such as conditionals and (primitive or general) recursion. We describe a uniform and optimal implementation, in Lamping's style, for all these features. The paper is the natural continuation of [3], where we focused on the theoretical aspects of optimal reductions in Interaction Systems (family relation, labeling, extraction).

A main subset of the S. Marco V neutral densities measured by the Drag Balance Instrument (DBI) in the equatorial atmosphere at altitudes between 250 and 470 Km in the period April 21 – December 05 1988 has been subjected to systematic analysis at various phenomenological scales. This paper presents some results which can be relevant for global empirical modeling of the thermosphere. In particular the measured data are statistically compared with the MSIS86 model data. The comparison reveals non gaussian deviations with typical patterns which can be interpreted in terms of unmodeled seasonal variations; in particular we address in the paper the amplitude and the local time of the peak of the midnight secondary density maximum. The peak local time appears to be seasonally variable, consistently with published data on the temperature secondary peak and which explains the patterns of the observed deviations with respect to MSIS86.

We provide a new characterization of Lévy's redex-families in the λ-calculus (Lévy, 1978) as suitable paths in the initial term of the derivation. The idea is that redexes in a same family are created by “contraction” (via β-reduction) of a unique common path in the initial term. This fact gives new evidence about the “common nature” of redexes in a same family, and about the possibility of sharing their reduction. In general, paths seem to provide a very friendly and intuitive tool for reasoning about redex-families, as well in theory (using paths, we shall provide a remarkably simple proof of the equivalence between extraction (Lévy, 1978) and labeling) as in practice (our characterization underlies all recent works on optimal graph reduction techniques for the λ-calculus (Lamping, 1990; Gonthier et al., 1992, Asperti, to appear), providing an original and intuitive understanding of optimal implementations).Finally, as an easy by-product of the path-characterization, we prove that neither overlining nor underlining are required in Lévy's labeling.

In this paper the notion of action atomicity is relaxed by permitting actions to be observed in the middle of their evolution. Non-atomic semantic equivalences, based on the notion of bisimulation, are studied over stable event structures, Split n bisimulation equivalence (denoted ∼ n considers each event as composed of n phases. ST bisimulation equivalence (denoted ∼ ST ) is a slight refinement of ∼ 2 where each ending phase is unambiguously associated to a beginning phase, We prove that, by increasing n , we get finer and finer equivalences (i.e., ∼ n + 1 ⊆ ∼ n ) and, moreover, that ∼ n + 1 coincides with ∼ ST over those event structures whose autoconcurrency is at most n . The main consequence of these results is that, for image finite event structures, ∼ ST is the intersection of all the ∼ n .

The λ-calculus with multiplicities is a refinement of the lazy λ-calculus where the argument in an application comes with a multiplicity, which is an upper bound to the number of its uses. This introduces potential deadlocks in the evaluation. We study various observation scenarios for this calculus, depending on the way we observe termination, deadlock and divergence. We relate these observational semantics with the intensional interpretation of λ-terms, by means of Lévy-Longo trees. We show in particular that the inclusion of such trees coincides with the “flat” observational semantics, where deadlocks and convergence are distinguished.

The λ-calculus with multiplicities is a refinement of the lazy λ-calculus where the argument in an application comes with a multiplicity, which is an upper bound to the number of its uses. This introduces potential deadlocks in the evaluation. We study various observation scenarios for this calculus, depending on the way we observe termination, deadlock and divergence. We relate these observational semantics with the intensional interpretation of λ-terms, by means of Levy-Longo trees. We show in particular that the inclusion of such trees coincides with the “flat” observational semantics, where deadlocks and convergence are distinguished.

The evaluation and management of potential arterial injuries in penetrating neck trauma are controversial. Routine surgical exploration or arteriography can be very expensive and time-consuming and can overburden available resources if used in all patients. We reviewed the records of 4035 patients seen in our trauma center during a 20-month period and identified a total of 110 patients (2.7%) with penetrating wounds to zone II of the neck; 50 were from gunshot wounds, 43 from stab wounds, 7 from shotgun injuries, and 10 from lacerations. In 42 (39%) patients there was no arteriogram or surgery based on location of the wounds or lack of any physical findings. None of these patients later had any evidence of an arterial injury. Forty-five patients (40%) had arteriograms based on proximity or a “soft” sign of vascular injury, which included evidence of significant bleeding or a stable hematoma. A total of 15 injuries to major arteries were identified: 3 common carotid, 5 internal carotid, and 7 vertebral. One patient died during initial resuscitation, and four patients went directly to surgery with no preoperative arteriogram for active bleeding and expanding hematoma (n = 1), an expanding hematoma (n = 2), and a large, stable hematoma (n = 1). Only one patient (of the 110) had a significant major arterial injury requiring surgery that was not predicted by physical findings. Nine arterial injuries were treated nonoperatively: six vertebral, two common carotid intimal flaps, and one small distal internal carotid pseudoaneurysm (diagnosed late). Three additional minor external carotid artery injuries were observed with no adverse sequelae. Associated neck injuries included 8 to the larynx/trachea, 7 to the esophagus, 11 to the pharynx, and 9 to the spinal cord. Associated injuries caused seven other deaths in this series. These results indicate that clinical evaluation is highly accurate in determining which patients need surgical intervention. Arteriograms have too low a yield ( J Vasc Surg 1992;16:397–401.)