Intra-specific variability and unusual organization of the repetitive units in a satellite DNA from Rana dalmatina: molecular evidence of a new mechanism of DNA repair acting on satellite DNA.

We have characterized the S1 satellite from eight European populations of Rana dalmatina by Southern blot, cloning and a new method that determines the sequence variability of repetitive units in the genome. This report completes our previous studies on this satellite DNA family, thus providing the first characterization of the overall variability of the structure and genomic organization of a satellite DNA within a species and among related species. The S1 satellite from R. dalmatina has a pericentromeric location on ten chromosome pairs and presents two homologous repeats S1a (494 bp) and S1b (332 bp), mostly organized as composite S1a-S1b repetitive units. In other brown frog species, both repeats have different sequences and locations, and are usually organized as separate arrays, although composite S1a-S1b repeats represent a minor, widely variable component in Rana italica. The average genomic sequences indicate that the species contains an enormous number of variants of each repeat derived from a unique, species-specific common sequence. The repeat variability is restricted to specific base changes in specific sequence positions in all population samples. Our data show that the structure and evolution of S1 satellite family is not due to crossing-over and gene conversion, but to a mechanism that maintains the ability of the satellite DNA to assemble in constitutive heterochromatin by replacing altered satellite segments with new arrays generated by rolling circle amplification. The mode of action of this repair process not only directly explains the intra- and inter-specific variability of the structure and organization of the S1 satellite repeats from European brown frogs, but also accounts for all general features of satellite DNA in eukaryotes, including its discontinuous evolution. This repair mechanism can maintain the satellite structure in a species indefinitely, but also promote a rapid generation of new variants or types of satellite DNA when environmental conditions favor the formation of new species

The first characterisation of the overall variability of repetitive units in a species reveals unexpected features of satellite DNA.

We investigated the overall variability of the S1a satellite DNA repeats in ten European populations of Rana temporaria by a new procedure that determines the average sequence of the repeats in a genome. The average genomic sequences show that only 17% of the S1a repeat sequence (494 bp) is variable. The variable positions contain the same major and minor bases in all or many of the population samples tested, but the percentages of these bases can greatly vary among populations. This indicates the presence in the species of an enormous number of repeats having a different distribution of bases in these variable positions. Individual genomes contain thousands of repeat variants, but these mixtures have very similar characteristics in all populations because they present the same type of restricted and species-specific variability. Southern blots analyses and sequences of cloned S1a repeats fully support this conclusion. The S1 satellite DNA of other European brown frog species also presents properties indicating the same type of variability. This first characterisation of the overall repeat variability of a satellite DNA in a species has revealed features that cannot be determined by gene conversion and crossing over. Our results suggest that a specific directional process based on rolling circle amplification should play a relevant role in the evolution of satellite DNA

A Model For e-Government Digital Document

The presence of a great amount of information is typical of bureaucratic processes, like the ones pertaining to public and private administrations. Such information is often recorded on paper or in different digital formats and its management is very expensive, both in terms of space used for storing documents and in terms of time spent in searching for the documents of interest. Furthermore, the manual management of these documents is absolutely not error-free. To efficiently access the information contained in very large document repositories, such as public administration archives, techniques for syntactic and semantic document management are required, so to ensure a large and intense process of document dematerialization, and eliminate, or at least reduce, the quantity of paper documents. In this work we present a novel RDF model of digital documents for improving the dematerialization effectiveness, that constitutes the starting point of an information system able to manage documental streams in the most efficient way. Such model takes into account the important need that is required in several E-Government applications which, depending on authorities or final users or time, provides different representations of the same multimedia contents

HOLMeS: eHealth in the Big Data and Deep Learning Era

Now, data collection and analysis are becoming more and more important in a variety of application domains, as long as novel technologies advance. At the same time, we are experiencing a growing need for human–machine interaction with expert systems, pushing research toward new knowledge representation models and interaction paradigms. In particular, in the last few years, eHealth—which usually indicates all the healthcare practices supported by electronic elaboration and remote communications—calls for the availability of a smart environment and big computational resources able to offer more and more advanced analytics and new human–computer interaction paradigms. The aim of this paper is to introduce the HOLMeS (health online medical suggestions) system: A particular big data platform aiming at supporting several eHealth applications. As its main novelty/functionality, HOLMeS exploits a machine learning algorithm, deployed on a cluster-computing environment, in order to provide medical suggestions via both chat-bot and web-app modules, especially for prevention aims. The chat-bot, opportunely trained by leveraging a deep learning approach, helps to overcome the limitations of a cold interaction between users and software, exhibiting a more human-like behavior. The obtained results demonstrate the effectiveness of the machine learning algorithms, showing an area under ROC (receiver operating characteristic) curve (AUC) of 74.65% when some first-level features are used to assess the occurrence of different chronic diseases within specific prevention pathways. When disease-specific features are added, HOLMeS shows an AUC of 86.78%, achieving a greater effectiveness in supporting clinical decisions

An Efficient Decentralized Multidimensional Data Index: A Proposal

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The management of dissolved oxygen by a polypropylene hollow fiber membrane contactor affects wine aging

Background: Numerous oenological practices can cause an excess of dissolved oxygen in wine, thus determining sensory and chromatic defects in the short‐ to long‐term. Hence, it is necessary to manage the excess of oxygen before bottling. Methods: In this study, the management of the dissolved oxygen content by a polypropylene hollow fiber membrane contactor apparatus was performed in two wines from different grape varieties (Aglianico and Falanghina). The wines were analyzed after an 11‐month aging. Anthocyanins and acetaldehyde content were evaluated by HPLC. In addition, other phenolic compounds and chromatic characteristics were analyzed by spectrophotometric methods. NMR and HR ESIMS analyses were conducted to evaluate the amount of pyranoanthocyanins and polymeric pigments. Results: After 11 months of aging, in both wines a decrease of free and total SO2 with respect to initial values was detected. In the wines with the highest dissolved oxygen levels, a more remarkable loss was observed. No significant differences in terms of color parameters were detected. In red wine with the highest oxygen content, a massive formation of polymeric pigments and BSA reactive tannins was observed, as opposed to wines with lower oxygen levels. Conclusion: The study demonstrated that the membrane contactor can prove a successful tool to manage dissolved oxygen in wines as to prevent their oxidative spoilage. © 2021 by the authors. Licensee MDPI, Basel, Switzerland

SemTree: An index for supporting semantic retrieval of documents

In this paper, we propose SemTree, a novel semantic index for supporting retrieval of information from huge amount of document collections, assuming that semantics of a document can be effectively expressed by a set of (subject, predicate, object) statements as in the RDF model. A distributed version of KD-Tree has been then adopted for providing a scalable solution to the document indexing, leveraging the mapping of triples in a vectorial space. We investigate the feasibility of our approach in a real case study, considering the problem of finding inconsistencies in documents related to software requirements and report some preliminary experimental results

A Framework for Recommending Multimedia Cultural Visiting Paths

In this work, we present a general framework for Cultural Heritage applications able to uniformly manage heterogeneous multimedia data coming from several web repositories and to provide context- Aware recommendation services in order to generate dynamic multimedia visiting paths useful for the users during the exploration of different kinds of cultural sites. A specific application of our system within the cultural heritage domain is proposed together with some experimental results

Diencephalic Syndrome Due to Optic Pathway Gliomas in Pediatric Patients: An Italian Multicenter Study

: Diencephalic syndrome (DS) is a rare pediatric condition associated with optic pathway gliomas (OPGs). Since they are slow-growing tumors, their diagnosis might be delayed, with consequences on long-term outcomes. We present a multicenter case series of nine children with DS associated with OPG, with the aim of providing relevant details about mortality and long-term sequelae. We retrospectively identified nine children (6 M) with DS (median age 14 months, range 3-26 months). Four patients had NF1-related OPGs. Children with NF1 were significantly older than sporadic cases (median (range) age in months: 21.2 (14-26) versus 10 (3-17); p = 0.015). Seven tumors were histologically confirmed as low-grade astrocytomas. All patients received upfront chemotherapy and nutritional support. Although no patient died, all of them experienced tumor progression within 5.67 years since diagnosis and were treated with several lines of chemotherapy and/or surgery. Long-term sequelae included visual, pituitary and neurological dysfunction. Despite an excellent overall survival, PFS rates are poor in OPGs with DS. These patients invariably present visual, neurological or endocrine sequelae. Therefore, functional outcomes and quality-of-life measures should be considered in prospective trials involving patients with OPGs, aiming to identify "high-risk" patients and to better individualize treatment