OLAP query reformulation in peer-to-peer data warehousing

Inter-business collaborative contexts prefigure a distributed scenario where companies organize and coordinate themselves to develop common and shared opportunities, but traditional business intelligence systems do not provide support to this end. To fill this gap, in this paper we envision a peer-to-peer data warehousing architecture based on a network of heterogeneous peers, each exposing query answering functionalities aimed at sharing business information. To enhance the decision making process, an OLAP query expressed on a peer needs to be properly reformulated on the local multidimensional schemata of the other peers. To this end, we present a language for the definition of mappings between the multidimensional schemata of peers and we introduce a query reformulation framework that relies on the translation of mappings, queries, and multidimensional schemata onto the relational level. Then, we formalize a query reformulation algorithm and prove two properties: correctness and closure, that are essential in a peer-to-peer setting. Finally, we discuss the main implementation issues related to the reformulation setting proposed, with specific reference to the case in which the local multidimensional engines hosted by peers use the standard MDX language.     

Rewriting rules to permeate complex similarity and fuzzy queries within a relational database system

In recent years, the availability of complex data repositories (e.g., multimedia, genomic, semistructured databases) has paved the way to new potentials as to data querying. In this scenario, similarity and fuzzy techniques have proven to be successful principles for effective data retrieval. However, most proposals are domain specific and lack of a general and integrated approach to deal with generalized complex queries, i.e., queries where multiple conditions are expressed, possibly on complex as well as on traditional data. To overcome such limitations, much work has been devoted to the development of middleware systems to support query processing on multiple repositories. On a similar line, We present a formal framework to permeate complex similarity and fuzzy queries within a relational database system. As an example, we focus on multimedia data, which is represented in an integrated view with common database data. We have designed an application layer that relies on an algebraic query language, extended with MM-tailored operators, and that maps complex similarity and fuzzy queries to standard SQL statements that can be processed by a relational database system, exploiting standard facilities of modern extensible RDBMS. To show the applicability of our proposal, we implemented a prototype that provides the user with rich query capabilities, ranging from traditional database queries to complex queries gathering a mixture of Boolean, similarity, and fuzzy predicates on the data.     

A proton and neutron beam polarimeter at SATURNE II

A beam polarimeter using CH₂ and carbon targets has been used to measure proton and neutron beam polarization in the energy range 0.4–2.8 GeV in one of the beam lines at the SATURNE II accelerator. The analyzing power for np-scattering is calibrated against the known analyzing power for pp-scattering by using the polarized deuteron beam to measure simultaneously the asymmetries for scattering of quasifree protons and neutrons in the deuterons. A low level of systematic errors is achieved by pulse to pulse polarization reversal at the ion source of the accelerator, and by measuring left and right scattering simultaneously. The detailed operation procedure and the beam polarizations measured during all experiments from 1981 to 1984 are presented.     

Hepatocellular Carcinoma in Chronic Viral Hepatitis: Where Do We Stand?

Hepatocellular carcinoma (HCC) is one of the major causes of cancer-related death. Although the burden of alcohol- and NASH-related HCC is growing, chronic viral hepatitis (HBV and HCV) remains a major cause of HCC development worldwide. The pathophysiology of viral-related HCC includes liver inflammation, oxidative stress, and deregulation of cell signaling pathways. HBV is particularly oncogenic because, contrary to HCV, integrates in the cell DNA and persists despite virological suppression by nucleotide analogues. Surveillance by six-month ultrasound is recommended in patients with cirrhosis and in “high-risk” patients with chronic HBV infection. Antiviral therapy reduces the risks of development and recurrence of HCC; however, patients with advanced chronic liver disease remain at risk of HCC despite virological suppression/cure and should therefore continue surveillance. Multiple scores have been developed in patients with chronic hepatitis B to predict the risk of HCC development and may be used to stratify individual patient’s risk. In patients with HCV-related liver disease who achieve sustained virological response by direct acting antivirals, there is a strong need for markers/scores to predict long-term risk of HCC. In this review, we discuss the most recent advances regarding viral-related HCC.     

Lithographically directed assembly of one-dimensional DNA nanostructures via bivalent binding interactions

In order to exploit the outstanding physical properties of one-dimensional (1D) nanostructures such as carbon nanotubes and semiconducting nanowires and nanorods in future technological applications, it will be necessary to organize them on surfaces with precise control over both position and orientation. Here, we use a 1D rigid DNA motif as a model for studying directed assembly at the molecular scale to lithographically patterned nanodot anchors. By matching the inter-nanodot spacing to the length of the DNA nanostructure, we are able to achieve nearly 100% placement yield. By varying the length of single-stranded DNA linkers bound covalently to the nanodots, we are able to study the binding selectivity as a function of the strength of the binding interactions. We analyze the binding in terms of a thermodynamic model which provides insight into the bivalent nature of the binding, a scheme that has general applicability for the controlled assembly of a broad range of functional nanostructures.      

Construction techniques for systematic SEC-DED codes with singlebyte error detection and partial correction capability for computermemory systems

Three new techniques are proposed for constructing a class of codes that extends the protection provided by previous single error correcting (SEC)-double error detecting (DED)-single byte error detecting (SBD) codes. The proposed codes are systematic odd-weight-column SEC-DED-SBD codes providing also the correction of any odd number of erroneous bits per byte, where a byte represents a cluster of b bits of the codeword that are fed by the same memory chip or card. These codes are useful for practical applications to enhance the reliability and the data integrity of byte-organized computer memory systems against transient, intermittent, and permanent failures. In particular they represent a good tradeoff between the overhead in terms of additional check bits and the reliability improvement, due to the capability to correct at least 50% of the multiple errors per byte     

Determination of proton beam polarization at high energies by measurements after deceleration

We are investigating a new method to determine the polarization of proton beams accelerated to high energies by measurements after deceleration to low energies, where simple and precise techniques can be used based on the large and well known analyzing power of pp elastic scattering. The polarized proton beam of SATURNE II was accelerated to 520 MeV and its polarization was measured by extracting the beam onto the NN beam line polarimeter.The beam was then accelerated to 800 MeV, decelerated to 520 MeV and again extracted. The loss in polarization is due to crossing twice the intrinsic depolarizing resonance γG = 3 at 631 MeV with adiabatic spin flip, once during acceleration and once during deceleration. The depolarization was intentionally increased by partially correcting the resonance, thus making the adiabatic flip less complete. The correction was introduced either at the rise or at the descent. The final polarization was the same in both cases showing that the depolarization was, as expected, the same during acceleration and deceleration. Another measurement was performed between 880 and 1200 MeV crossing successively two intrinsic resonances $\text{γG = ν}{}_{\mathrm{z}}\text{at}\text{?900}\text{Mev}$ and γG = 4 at 1145 MeV. Here the polarization at 1200 MeV was measured directly and is compared to the value calculated from the measurements at 880 MeV before accelerating to 1200 MeV and after decelerating from 1200 MeV, assuming symmetric depolarization. The measured and the calculated values agree with ΔP_B = 0.03 at $\text{P}{}_{\mathrm{B}}\text{? 0.75}$.     

Meeting new challenges in radon measurements service with solid state alpha track analysis

The national and international radioprotection legislation now covers exposures to the naturally occurring radioactive materials (NORM) with particular emphasis on radon in workplaces. Consequently, a number of working environments have now been brought into the realm of radiation protection monitoring with a corresponding increase in the demand for radon monitoring services. The new challenges occasioned by the increase in demands are illustrated in this paper together with the radon measurement system developed at the ENEA IRP radon Service. In particular, this paper emphasises how to control using hardware and software analysis, the distributions (diameters and areas) of the track shape, which directly affect the quality of the radon service.     

Silicon photomultipliers characterization for the EMR prototype of the MICE experiment

The SiPMs are excellent candidates for the replacement of PMTs in many experimental situations. In this article we describe the performances of different types of SiPMs from Hamamatsu and FBK-IRST before and after irradiation with photons and neutrons in terms of signal to noise ratio, time resolution and efficiency. The SiPMs are connected to a scintillation tracker/calorimeter, composed of eight layers (4x and 4y) of 10 scintillating bars each and have been tested at the CERN PS T9 beamline. The tracker/calorimeter is a small-size prototype of a bigger detector called EMR (Electron Muon Ranger), a particle identification system developed for the MICE experiment.