1,463 research outputs found
Shashlik Calorimeters with Embedded SiPMs for Longitudinal Segmentation
Effective longitudinal segmentation of shashlik calorimeters can be achieved taking advantage of the compactness and reliability of silicon photomultipliers. These photosensors can be embedded in the bulk of the calorimeter and are employed to design very compact shashlik modules that sample electromagnetic and hadronic showers every few radiation lengths. In this paper, we discuss the performance of a calorimeter made up of 12 such modules and able to sample showers every ∼ 4X0. In summer 2016, this prototype has been exposed to electrons, muons, and hadrons at CERN PS (East Area T9 beamline). The performances in terms of energy resolution, linearity, response to minimum ionizing particles, and reconstruction of the shower profile are discussed
Environmental control on the end of the Dolomia Principale/Hauptdolomit depositional system in the central Alps: Coupling sea-level and climate changes
The Norian in the Western Tethys is characterised by the deposition of early-dolomitised inner platform facies (Dolomia Principale/Hauptdolomit, DP/HD), bordered on the landward side by terrigenous coastal deposits (Keuper) and on the seaward side by calcareous backreef and reefal facies (Dachstein Limestone) passing basinward to open-sea sediments (Hallstatt facies). The inner carbonate platform is locally (Lombardy Basin, Carnic Alps, Central Austroalpine) dissected by normal faults leading to the development of intraplatform troughs.
Close to the Norian-Rhaetian boundary, sedimentation records an abrupt environmental change both on platform top and basins all over the Western Tethys (e.g. Western Carpathians, Transdanubian Range, Alps, Central Apennine). The top of the Dolomia Principale locally emerged, reflecting a major eustatic sea-level fall. Emersion is recorded in favourable settings by the development of polycyclic paleosols up to 30 m thick. In the Norian intraplatform basins, the succession is capped by 4 to 8 m of thin-bedded, fine-grained limestones yielding abundant remnants of fishes and terrestrial reptiles. Fossil concentration as well as sedimentological features is indicative of reduced sedimentation rates due to decreased carbonate production, induced by the emersion of the platform top. The sea-level fall was followed by deposition of mixed fine-grained siliciclastic-carbonate successions (e.g. Riva di Solto Shale, Kossen beds, "Rhaetavicula contorta beds", Fatra Formation).
Stratigraphic evidence indicates a dry climate in the Western Tethys during the Norian, as indicated by the presence of evaporites (Burano, Apennine) and arid to semi-arid coastal to playa settings (Upper Keuper, Germany). In contrast, the basal layers of the basinal shales show evidence of wet climate.
The end of the Norian depositional system records two different phenomena: (1) an important sea-level fall was responsible for the emersion of the platform top and deposition of a condensed horizon in the basins: and (2) transition from dry to humid climate. The observed evolution is explained with a global cooling which caused the rapid sea-level fall responsible for the abrupt end of the DP/HD depositional system and the shift of the boundary between arid and temperate climate belts, which modified the distribution and amount of rainfall, triggering the deposition of shales along the Western Tethys margin
Encrinus aculeatus von Meyer, 1849 (Crinoidea, Encrinidae) from the Middle Triassic of Val Brembana (Alpi Orobie, Bergamo, Italy)
The Triassic crinoid Encrinus aculeatus is described from a single bedding plane of uncertain Pelsonian or early Illyrian or (less probable) late Ladinian origin from Val Brembana (Alpi Orobie, Bergamo, Italy) based on 36 more or less complete crowns and columns. The specimens represent an obrutional echinoderm lagerst\ue4tte of the Muschelkalk type. The individuals are semi-adult and juvenile; adult individuals are lacking. Morphological description and comparison with the holotype and additional material from the Lower Muschelkalk and basal Middle Muschelkalk of Upper Silesia (Poland) prove the assignment to Encrinus aculeatus. However, the species concept of genus Encrinus is critical because several characters are inconsistent. E. aculeatus occurs in the Middle Triassic (Bithynian to early Illyrian, ? early Ladinian) of the western Tethys shelf and Peritethys basins (Southern Alps, Balaton Upland, Germanic Basin). Encrinus aculeatus is regarded ancestral to the Upper Muschelkalk (latest Illyrian) E. liliiformis. Until now, E. liliiformis has not yet been proven with certainty from outside the Germanic Basin; references are based on isolated and undiagnostic material
Radiological and surgical aspects of polymorphous low-grade neuroepithelial tumor of the young (PLNTY)
Background: Polymorphous low-grade neuroepithelial tumor of the young (PLNTY) is a low-grade epilepsy-associated tumor recently introduced in WHO 2021 classification. Since it has been recognized as an independent nosological entity, PLNTY has been mainly studied from a genetic and molecular perspective, not recognizing unique characteristic clinical and radiological features. Methods: A systematic literature research has been conducted aiming to identify all relevant studies about the radiological, clinical and surgical features of PLNTY. We described a representative case of a 45-year-old man treated with awake-surgery with confirmed diagnosis of PLNTY, reporting the radiological and surgical characteristics through imaging and intra-operative video. We performed a statistical meta-analysis attempting to assess the presence of relationships between surgical and radiologic tumor characteristics and clinical outcome and type of surgery. Results: A total of 16 studies were included in the systematic review. The final cohort was composed of 51 patients. Extent of resection (EOR) and outcome are not significantly associated with the different genetic profiling (p = 1), the presence of cystic intralesional component, calcification (p = 0.85), contrast-enhancing and lesion boundaries (p = 0.82). No significant correlation there is between EOR and remission or better control of epilepsy-related symptoms (p = 0.38). The contrast enhancement in the tumor is significantly associated with recurrence or poor control of epileptic symptoms (p = 0.07). Conclusions: In PLNTYs, contrast enhancement seems to impact prognosis, recurrence, and seizure control much more than radiological features, genetic features and type of resection of the tumor
Large-scale progradation, demise and rebirth of a high-relief carbonate platform (Triassic, Lombardy Southern Alps, Italy)
The Upper Anisian to Early Carnian succession of the Middle Val Brembana-Pegherolo Massif (Central Southern Alps of Italy) records a complete depositional cycle from platform inception to growth, demise and rebirth. The depositional architecture of this system reflects different evolutionary stages: an inception stage which postdates a previous drowning of an Anisian carbonate platform with progradation of the carbonate platform from the nucleation areas, an aggradational stage with increasing water depth in the basins, a progradational stage where steep slopes composed of margin-derived breccias develop and a final crisis corresponding to the subaerial exposure of the platform top, followed by the deposition of shales in the basin before the rebirth of a different type of carbonate factory. The record of this evolution reflects the effects of the change in accommodation space (interplay of subsidence and eustacy), which controls the type and storage sites of the sediments produced by the carbonate factory. The effects of the changes in accommodation space are recorded in the shallow water platform as well as in the intraplatform basins, where the sediments, delivered at different rates from the platform top are stored. As a consequence, the aggradational stage corresponds to reduced sedimentation in the basins (i.e. sediments are stored on the platform top) whereas during progradation resedimented limestones are more common in the basin. Subaerial exposure rapidly halted the carbonate production on the platform top, while a major input of shales (probably reflecting a climate change and/or lowering of the base level) is recorded in the basin, where shales onlap the slope of the previous carbonate system. The rebirth of the carbonate factory after subaerial exposure of the platform top is characterized by a different composition of the carbonate factory, probably reflecting changes of the environmental conditions. The step-by-step recording of the evolution of the carbonate system represents a unique opportunity to record a seismic-scale complete evolutionary cycle of a carbonate system in its different sub-environments, from the platform top to the basin
Risk genes in head and neck cancer: a systematic review and meta-analysis of last 5 years
Head and Neck Carcinoma (HNC), of which the majority are squamous cell carcinomas of the head and neck (SCCHN), is the sixth most prevalent cancers in mankind and, presents high morbidity and low rates of survival.1 It is known that the apoptotic and proliferation genes are involved in cancer development and these could be useful as a biomarker of this pathology. Systematic reviews and meta-analysis allow stronger and more generalized conclusions for identifying some models of risk markers. These models may help in screening, early diagnosis and/or therapy in the clinic.2-5 In recent decades, there has been increased interest in genetic predisposition studies in complex disease. This has led to the production of an enormous number of epidemiologic papers about the relationship between genetic polymorphism and disease. However, the magnitude of association between specific polymorphism and disease is still not established. The identification of a predictive model of risk polymorphisms could help in early diagnosis, and in understanding disease recurrence and/or progression in the subset of patientssubmittedVersio
An Architecture for distributed multimedia database systems
In the past few years considerable demand for user oriented multimedia information systems has developed. These systems must provide a rich set of functionality so that new, complex, and interesting applications can be addressed. This places considerable importance on the management of diverse data types including text, images, audio and video. These requirements generate the need for a new generation of distributed heterogeneous multimedia database systems. In this paper we identify a set of functional requirements for a multimedia server considering database management, object synchronization and integration, and multimedia query processing. A generalization of the requirements to a distributed system is presented, and some of our current research and developing activities are discussed
Towards a Geological Information System: the CARGeo System and the Regione Lombardia Geological Database.
In the framework of the national mapping program «CARGNew
Italian Geological Map at 1:50.000 scale», Regione Lombardia is
generating a detailed map (1:10.000 scale) of its territory. Surveying
criteria have been carefully defined in order to produce homogeneous
geological maps: geological survey has been performed at the
1:10.000 scale, and data have been stored in a GIS-oriented database.
The detailed survey scale improved the geological knowledge: the
new maps represent an important tool for territorial planning requirements
of public administrations and engineering geologists (e.g. in
hydrogeological and seismic risk evaluation).
Field geologists performed data input in the geological data
base by alternating field campaigns and data input throughout the
year, taking advantage of periods when field activities are slackened
(i.e. according to climate conditions). In this way, data entry is
nearly synchronous with data collection, and field data become
quickly accessible. Data entry by the field geologists on one side
slows down the field activity, however, it guarantees a precise digitalization
of geometric data and a correct attribute assignment, allowing
to optimize working time.
To allow the data entry to non-GIS-specialized users, we developed
an ArcView®-VisualBasic®-MSAccess® application, enabling the
simultaneous acquisition of geometric and alphanumeric data. Data
base management and cartographic production are performed with
ArcInfo®, through specific procedures which, after data reorganization
and control (both alphanumeric and geometric), lead to the final
cartographic output at different scales.
The 1:10.000 geological database is migrated in the ArcSDE
structure and prepared for data view, query and download
(www.cartografia.regione.lombardia.it/cargweb) using ESRI (ArcIMS)
tools.
From the 1:10.000 geological database we derived the database
for the 1:50.000 CARG maps by both automatic and manual generalization
according to the CARG-APAT standards. During the different
phases of the project, several problems arose, due to both
project organization and data storage system (from data collection
in the field to elaboration and digitalization, and, in case, to final publication).
– Data collection: the survey activity was divided between «bedrock
» and «quaternary» specialists. The double survey provided a
high-quality geological description of the territory, but slowed the
generation of the data-flow. Based on this experience, the last assigned
areas are surveyed by a single geologist, under the supervision
of quaternary and bedrock experts.
– Users feedback: geologists are normally used to draw their
maps on paper; learning how to produce electronic maps can be difficult,
and the software tools have to be studied very carefully and
present user friendly interfaces. Nevertheless, in our experience, a
training period has to be planned, and geologists have to be supported
by a GIS expert, who can understand their needs and modify the
software accordingly.
– System architecture: the ArcView®-VisualBasic®-MSAccess®
(Windows platform) – ArcInfo® (UNIX platform) environment, revealed
problems in the client-server stability of an earlier version; some
unsolved troubles remain, mainly related to the network architecture.
The presence in the CARG-Regione Lombardia crew of consultant
geologists, experienced and trained in collection, analysis and data entry
in the final database, accelerated the critical phases of:
– Data base derivation from Regione Lombardia dataset to CARG-APAT standard
Rapid isolation of pure Complement Factor H from serum for functional studies by the use of a monoclonal antibody that discriminates FH from all the other isoforms
Several mutations have been identified in the gene coding for Complement Factor H (FH) from patients with atypical Hemolytic Uraemic Syndrome (aHUS), Age-related Macular Degeneration (AMD) and Membranoproliferative Glomerulonephritis (MPGN). These data allow for a precise description of the structural changes affecting FH, but a simple test for specifically assessing FH function routinely is not yet of common use. We have produced and characterised a monoclonal antibody (5H5) which discriminates between FH and the smaller FH-like 1 and FH-related proteins and show here that it specifically binds to FH without detecting the smaller isoforms. We therefore used this mAb for a quick, one-step micro-purification of FH directly from control sera and showed that this affinity chromatography procedure is not disruptive of its cofactor function. We also developed a modified sheep erythrocytes haemolysis test using our antibody and affinity-purified FH. These tests can be used in conjunction for assessing the function of FH purified from patients affected by FH-related diseases. Moreover we used this mAb to develop a FH-specific ELISA test
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