Groups of Transformations with a Finite Number of Isometries: the Cases of Tetrahedron and Cube

This paper deals with groups of transformations with finite number of isometrics and, therefore, appears as the completion of previous and published works (Casolaro, F. L. Cirillo and R. Prosperi 2015) related only to endless groups of transformations with isometrics. In particular isometries of the tetrahedron and the cube are presented which turn these figures in itself

Approssimazione di funzioni di matrici con struttura di banda

La tesi si basa sull'approssimazione di funzioni di matrici f(A), nel caso in cui A possegga struttura di banda ed f sia una mappa abbastanza regolare. Dopo aver introdotto le essenziali notazioni e definizioni, proveremo che, se A è a banda, allora sotto certe ipotesi f(A) presenta la proprietà di decadimento esponenziale degli elementi man mano che ci si allontana dalla banda di A. Questo permette di costruire algoritmi che approssimano f(A) con una matrice a banda. Presenteremo metodi che agiscono in tal senso, li implementeremo in linguaggio MATLAB in modo che sfruttino la struttura di banda ed effettueremo alcuni esperimenti numerici per testarne l'accuratezza

S100B inhibitor pentamidine attenuates reactive gliosis and reduces neuronal loss in a mouse model of Alzheimer's disease

Among the different signaling molecules released during reactive gliosis occurring in Alzheimer’s disease (AD), the astrocytederived S100B protein plays a key role in neuroinflammation, one of the hallmarks of the disease. The use of pharmacological tools targeting S100B may be crucial to embank its effects and some of the pathological features of AD. The antiprotozoal drug pentamidine is a good candidate since it directly blocks S100B activity by inhibiting its interaction with the tumor suppressor p53. We used a mouse model of amyloid beta- (A-) induced AD, which is characterized by reactive gliosis and neuroinflammation in the brain, and we evaluated the effect of pentamidine on the main S100B-mediated events. Pentamidine caused the reduction of glial fibrillary acidic protein, S100B, and RAGE protein expression, which are signs of reactive gliosis, and induced p53 expression in astrocytes. Pentamidine also reduced the expression of proinflammatory mediators and markers, thus reducing neuroinflammation in AD brain. In parallel, we observed a significant neuroprotection exerted by pentamidine on CA1 pyramidal neurons. We demonstrated that pentamidine inhibits A-induced gliosis and neuroinflammation in an animal model of AD, thus playing a role in slowing down the course of the disease

An experimental investigation on effect of pores per inch in compact heat exchanger with aluminum foam

Metal foams are a new class of materials with low densities and novel thermal and mechanical properties. Aluminum foams combine low weight with good rigidity, strength, damping of vibrations and noise, shock resistance and low thermal conductivity [1]. An experimental investigation on a single row of aluminum tubes, covered with layers of aluminum foams, was carried out by T’joen et al. [2]. A range of foam layer thickness, Reynolds number tube spacing and different type of foam were considered and compared with compact helically finned tube heat exchangers. An experimental investigation was carried out by Sertkaya et al. [3] to compare three metal foam heat exchangers (10, 20 and 30 PPI) to three finned heat exchangers with the same tube layout and overall dimensions. Please download the full abstract below

Altered Spinal Homeostasis and Maladaptive Plasticity in GFAP Null Mice Following Peripheral Nerve Injury

The maladaptive response of the central nervous system (CNS) following nerve injury is primarily linked to the activation of glial cells (reactive gliosis) that produce an inflammatory reaction and a wide cellular morpho-structural and functional/metabolic remodeling. Glial acidic fibrillary protein (GFAP), a major protein constituent of astrocyte intermediate filaments (IFs), is the hallmark of the reactive astrocytes, has pleiotropic functions and is significantly upregulated in the spinal cord after nerve injury. Here, we investigated the specific role of GFAP in glial reaction and maladaptive spinal cord plasticity following sciatic nerve spared nerve injury (SNI) in GFAP KO and wild-type (WT) animals. We evaluated the neuropathic behavior (thermal hyperalgesia, allodynia) and the expression of glial (vimentin, Iba1) and glutamate/GABA system markers (GLAST, GLT1, EAAC1, vGLUT, vGAT, GAD) in lumbar spinal cord sections of KO/WT animals. SNI induced neuropathic behavior in both GFAP KO and WT mice, paralleled by intense microglial reaction (Iba1 expression more pronounced in KO mice), reactive astrocytosis (vimentin increase) and expression remodeling of glial/neuronal glutamate/GABA transporters. In conclusion, it is conceivable that the lack of GFAP could be detrimental to the CNS as it lacks a critical sensor for neuroinflammation and morpho-functional-metabolic rewiring after nerve injury. Understanding the maladaptive morpho-functional changes of glial cells could represent the first step for a new glial-based targeted approach for mechanisms of disease in the CNS

Experimental Investigation on Fluid Dynamic and Thermal Behavior in Confined Impinging Round Jets in Aluminum Foam

In this paper an experimental investigation is carried out on impinging jets in porous media with the wall heated from below with a uniform heat flux. The fluid is air. The experimental apparatus is made up of a fun systems, a test section, a tube, to reduce the section in a circular section. The tube is long 1.0 m and diameter of 0.012 m. The test section has a diameter of 0.10 m and it has the thickness of 10, 20 and 40 mm. In the test section the lower plate is in aluminum and is heated by an electrical resistances whereas the upper plate is in Plexiglas. The experiments are carried out employing aluminum foams with 5, 10 and 40 PPI and three thickness over the heated circular plate. Results are obtained in a Reynolds number range from 500 to 1500 and wall heat flux from 500 W/m2 to 1400 W/m2. Results are given in terms of wall temperature profiles, local and average Nusselt numbers, pressure drops, friction factor and Richardson number. Moreover, to evaluate the improvement due to the presence of the metal foam, it is necessary a quantitative methodology. In this work an energy performance ratio is employed to compare the performances of surface with and without foams in terms of heat transfer coefficients and pressure drops. Preliminarily experimental results has confirmed that the use of the porous medium improves the heat transfer promoting the heat dissipation of the surface with high efficacy but determines an increase in pressure drops

Ophiolitic sequences from the central sector of the Catena Costiera (Calabria): stratigraphy, petrology and structural analyses

Mesozoic ophiolites crop out in the Catena Costiera (Northern Calabrian Arc). The Northern Calabrian Arc is characterized by the superposition of three structural elements (OGNIBEN, 1973): the uppermost Hercynian continental section intruded by late- Variscan granitoids (Calabrian Nappe), the intermediate ophiolitic Nappe and the lowermost Mesozoic passive margin carbonate sequences (Apenninic Units). The studied area is located in the central Catena Costiera (fig. 1) where the ophiolitic sequences are characterized by both aphyric and porphyritic metabasalts with a T-MORB affinity (LIBERI et alii, 2006). They represent the basement of a peliticarenaceous metasedimentary sequence, previously interpreted as a pre-Mesozoic continental basement (Bagni Unit of AMODIO MORELLI et alii, 1976). In the metasedimentary cover, a remarkable increase in the carbonatic supply is noticed moving from south to north of the study area. According to this evidence two stratigraphic sequences have been defined for the southernmost Cozzo Cervello area and the northernmost San Martino di Finita area. The Cozzo Cervello area ophiolitic sequence is characterized by: metabasites, thin levels of volcanoclastic metasediments, rare metacarbonates, metapelites and metarenites. The San Martino di Finita area ophiolitic sequence is instead characterized by: metabasites, volcanoclastic metasediments and calcschists. The studied rocks underwent a polyphase deformation history and the meso- and microstructural analyses allowed distinguishing three main (D1-D3) deformation phases: – D1, this phase is characterized by a S1 foliation locally developed and preserved as microlithons inside the S2 main foliation; – D2, a N-S trending isoclinal folding event (F2; fig. 2 a,b) is responsible for the formation of the S2 foliation (fig. 2 d), that represent the main surface recognizable in the field; – D3, this phase is characterized by asymmetric folds (F3) developed at different scales and showing a WNW-ESE trending axes. An incipient foliation (S3) is locally developed in the phyllosilicate-rich levels (fig. 2 c,d). *Dipartimento di Scienze della Terra, Università della Calabria. ([email protected]) **Dipartimento di Scienze della Terra, Università di Pisa The petrographic analysis allows to define the mineralogical assemblage of the different lithotypes and to determine the relationships between deformation and blastesis. The metabasites are characterized by the mineralogical assemblage: Epidote + Na-amphibole + Lawsonite + Phengite + Chlorite + Albite Calcite Quartz + Magnetite. Metapelites and metarenites are characterized by: Epidote + Phengite + Stilpnomelane + Na-Amphibole + Pumpellyite + Chlorite + Albite + Quartz + Magnetite. The calcschist are constituted by: Calcite + Phengite + Chlorite + Albite + Quartz + Magnetite. The described mineralogical assemblages suggest that the studied rocks underwent P-T conditions typical of the blueschist facies as suggested by the blastesis of Na-amphiboles, lawsonite, stilpnomelane and phengite along the S2 foliation. The blastesis of white mica can be observed along the S3 foliation also. The following metamorphic retrogression developed within the prehnitepumpellyite facies and is characterized by a static recrystalization. Fig. 1 – Tectonic sketch map of central sector of the Catena Costiera, after LIBERI et alii (2006). 64 OPHIOLITIC SEQUENCES FROM THE CATENA COSTIERA 65 Fig. 2 – a) isoclinal folds (F2) in the metapelites of Cozzo Cervello area; b) isoclinal folds (F2) in the calcschists of San Martino di Finita area; c) crenulation F3 in the metabasites; d) microscopic view of the main foliation S2 deformed by the later D3 phase in the metapelites. The white line indicates white mica flakes along S3. The field study and the tectonometamorphic evolution reconstructed for the ophiolitic sequences cropping out in the central sector of the Catena Costiera of Calabria show that a subduction and exhumation history inside an accretionary wedge can be proposed. In particular, the characterization and the definition of the complex relationships existing within the ophiolitic metasedimentary cover allow us to propose: 1. the source area was composite, with both carbonatic and siliciclastic contributions; 2. the presence of terrigenous deposit, even in the lowermost part of the sedimentary sequence, seem to indicate that this part of oceanic crust was located close to the continental margin; 3. the San Martino di Finita type sedimentary cover can be correlated with that of the Malvito ophiolitic unit (sensu AMODIO MORELLI et alii, 1976), cropping out in the northernmost sector of the Catena Costiera; 4. the subdivision between the Bagni and Gimigliano-Monte Reventino Units, as proposed by DIETRICH & SCANDONE (1972) and AMODIO MORELLI et alii (1976) for the study area, is not supported by the data collected in this work. REFERENCES AMODIO MORELLI L., BONARDI G., COLONNA V., DIETRICH D., GIUNTA G., IPPOLITO F., LIGUORI V., LORENZONI S., PAGLIONICO A., PERRONE V., PICCARRETA G., RUSSO M., SCANDONE P., ZANETTIN-LORENZONI E. & ZUPPETTA A. (1976) - L’arco Calabro-peloritano nell’orogene appenninicomagrebide. Mem. Soc. Geol. It, 17, 1–60. DIETRICH D. & SCANDONE P. (1972) - The position of the basic and ultrabasic rocks in the tectonic units of the southern Apennines. Atti Acc. Pont., 21, 61–75. LIBERI F., MORTEN L. & PILUSO E. (2006) - Geodynamic significance of the ophiolites within the Calabrian Arc. Island Arc, 15, 26–43. OGNIBEN L. (1973) - Schema geologico della Calabria in base ai dati odierni. Geologia Romana, 12, 243

A singular case of cavernous internal carotid artery aneurysm in patient with cavernous sinus syndrome and bacterial meningitis

AbstractWe report the uncommon case of an acute cavernous sinus syndrome in a patient who was consequently discovered to have both a cavernous internal carotid artery aneurysm and bacterial meningitis. Which came first, the chicken or the egg? Which of the two, the aneurysm or the meningitis, gave rise to the patient’s symptoms? We briefly reviewed the literature of similar cases and tried to analyze the possible pathophysiological relationship between these findings. Moreover, this case highlights the importance of a multidisciplinary management of these patients to better decide between a medical and a surgical and/or endovascular treatment

Compositional and Morphological Characterization of ‘Sorrento’ and ‘Chandler’ Walnuts

In Italy, most of the cultivated walnuts belong to the Sorrento ecotype, and they are considered commercially valuable due to their specific organoleptic characteristics. The aim of this study is to evaluate and compare the morphological and compositional characteristics of walnuts sampled from ‘Sorrento’ trees cultivated in different locations in Campania and trees of both the ‘Chandler’ and ‘Sorrento’ varieties derived from the same location. The results demonstrated that ‘Sorrento’ and ‘Chandler’ walnuts have different biometric characteristics and a different fat content, with the highest fat content being found in the ‘Sorrento’ variety. Regarding the fatty acid (FA) composition, the content of monounsaturated and saturated fatty acids (MUFAs and SFAs) was highest in the ‘Sorrento’ variety (from 13 to 15% for MUFAs and from 11 to 13% for SFAs), while the polyunsaturated fatty acids (PUFAs) content was highest in the ‘Chandler’ variety (77%). The total phenolics content (TPC) was highest in the ‘Sorrento’ variety (from 910 to 1230 mg GAE/100 g), while no difference in γ-tocopherol content was found. Furthermore, the influence of walnut area cultivation was shown for fat content, FA composition and TPC. Therefore, both walnut varieties demonstrated good nutritional properties considering the PUFAs and γ-tocopherol conten

miRNA Signatures in Sera of Patients with Active Pulmonary Tuberculosis.

Several studies showed that assessing levels of specific circulating microRNAs (miRNAs) is a non-invasive, rapid, and accurate method for diagnosing diseases or detecting alterations in physiological conditions. We aimed to identify a serum miRNA signature to be used for the diagnosis of tuberculosis (TB). To account for variations due to the genetic makeup, we enrolled adults from two study settings in Europe and Africa. The following categories of subjects were considered: healthy (H), active pulmonary TB (PTB), active pulmonary TB, HIV co-infected (PTB/HIV), latent TB infection (LTBI), other pulmonary infections (OPI), and active extra-pulmonary TB (EPTB). Sera from 10 subjects of the same category were pooled and, after total RNA extraction, screened for miRNA levels by TaqMan low-density arrays. After identification of "relevant miRNAs", we refined the serum miRNA signature discriminating between H and PTB on individual subjects. Signatures were analyzed for their diagnostic performances using a multivariate logistic model and a Relevance Vector Machine (RVM) model. A leave-one-out-cross-validation (LOOCV) approach was adopted for assessing how both models could perform in practice. The analysis on pooled specimens identified selected miRNAs as discriminatory for the categories analyzed. On individual serum samples, we showed that 15 miRNAs serve as signature for H and PTB categories with a diagnostic accuracy of 82% (CI 70.2-90.0), and 77% (CI 64.2-85.9) in a RVM and a logistic classification model, respectively. Considering the different ethnicity, by selecting the specific signature for the European group (10 miRNAs) the diagnostic accuracy increased up to 83% (CI 68.1-92.1), and 81% (65.0-90.3), respectively. The African-specific signature (12 miRNAs) increased the diagnostic accuracy up to 95% (CI 76.4-99.1), and 100% (83.9-100.0), respectively. Serum miRNA signatures represent an interesting source of biomarkers for TB disease with the potential to discriminate between PTB and LTBI, but also among the other categories