Electrical conductivity of carbon nanofiber reinforced resins: potentiality of Tunneling Atomic Force Microscopy (TUNA) technique

Epoxy nanocomposites able to meet pressing industrial requirements in the field of structural material have been developed and characterized. Tunneling Atomic Force Microscopy (TUNA), which is able to detect ultra-low currents ranging from 80 fA to 120 pA, was used to correlate the local topography with electrical properties of tetraglycidyl methylene dianiline (TGMDA) epoxy nanocomposites at low concentration of carbon nanofibers (CNFs) ranging from 0.05% up to 2% by wt. The results show the unique capability of TUNA technique in identifying conductive pathways in CNF/resins even without modifying the morphology with usual treatments employed to create electrical contacts to the ground

(s)INE: (soft-graft)-induced new entry tear after elephant trunk procedure

: Elephant trunk and frozen elephant trunk are established procedures for the treatment of aortic arch pathologies, such as aneurysm or dissection. The aim of open surgery is to re-expand the true lumen, favouring correct organ perfusion and the thrombosis of the false lumen. Frozen elephant trunk, with its stented endovascular portion, is sometimes associated with a life-threatening complication: the stent graft-induced new entry. In the literature, many studies reported the incidence of such issue after thoracic endovascular prosthesis or frozen elephant trunk, but in our knowledge, there are no case studies about the occurrence of stent graft-induced new entry with the use of soft grafts. For this reason, we decided to report our experience, highlighting how the use of a Dacron graft can cause distal intimal tears. We decided to coin the term soft-graft-induced new entry to indicate the development of an intimal tear induced by the soft prosthesis in the arch and proximal descending aorta

Automatic PET-CT Image Registration Method Based on Mutual Information and Genetic Algorithms

Hybrid PET/CT scanners can simultaneously visualize coronary artery disease as revealed by computed tomography (CT) and myocardial perfusion as measured by positron emission tomography (PET). Manual registration is usually required in clinical practice to compensate spatial mismatch between datasets. In this paper, we present a registration algorithm that is able to automatically align PET/CT cardiac images. The algorithm bases on mutual information (MI) as registration metric and on genetic algorithm as optimization method. A multiresolution approach was used to optimize the processing time. The algorithm was tested on computerized models of volumetric PET/CT cardiac data and on real PET/CT datasets. The proposed automatic registration algorithm smoothes the pattern of the MI and allows it to reach the global maximum of the similarity function. The implemented method also allows the definition of the correct spatial transformation that matches both synthetic and real PET and CT volumetric datasets

The Capitoline Temple of Jupiter.: The Best, the Greatest, but not Colossal

It is generally assumed that the temple of Jupiter Optimus Maximus was hexastyle, colossal, and occupied a rectangular platform consisting of a grid of cappellaccio walls that matched the measurements provided by Dionysius of Halicarnassus. Yet neither the Greek historian nor any other sources provide this information explicitly. We argue for a smaller, yet still huge, Capitoline temple that occupied one sector of the platform and was eventually framed by a colonnaded portico. The plan of our Tuscan temple matches the surviving foundations, is in accordance with Vitruvius and other sources, and follows the principles of Roman architecture. Its elevation takes into account the latest investigations and the recent finds of terracotta revetments from the Capitoline temple, is consistent with its depictions on coins and marble reliefs, and is supported by the first structural verification of the imperial entablature ever made to date. Finally we re-assess the cultural exchanges between Rome, Etruria, and the broader Mediterranean area in the light of the new reconstruction

Electrical conductivity of carbon nanofiber reinforced resins: Potentiality of Tunneling Atomic Force Microscopy (TUNA) technique

Epoxy nanocomposites able to meet pressing industrial requirements in the field of structural material have been developed and characterized. Tunneling Atomic Force Microscopy (TUNA), which is able to detect ultra-low currents ranging from 80 fA to 120 pA, was used to correlate the local topography with electrical properties of tetraglycidyl methylene dianiline (TGMDA) epoxy nanocomposites at low concentration of carbon nanofibers (CNFs) ranging from 0.05% up to 2% by wt. The results show the unique capability of TUNA technique in identifying conductive pathways in CNF/resins even without modifying the morphology with usual treatments employed to create electrical contacts to the ground

The role of carbon nanofiber defects on the electrical and mechanical properties of CNF-based resins

Heat treatment of carbon nanofibers has proven to be an effective method in removing defects from carbon nanofibers, causing a strong increase in their structural perfection and thermal stability. It affects the bonding states of carbon atoms in the nanofiber structure and causes a significant transformation in the hybridization state of the bonded carbon atoms.Nanofilled resins made of heat-treated CNF show significant increases in their electrical conductivity even at low concentrations. This confirms that enhancement in the perfection of the fiber structure with consequent change in the morphological features plays a prominent role in affecting the electrical properties. Indeed heat-treated CNFs display a stiff structure and a smooth surface which tends to lower the thickness of the unavoidable insulating epoxy layer formed around the CNF which, in turn, plays a fundamental role in the electrical transport properties along the conducting clusters. This might be very beneficial in terms of electrical conductivity but might have negligible effect on the mechanical properties

Optimization of Graphene-Based Materials Outperforming Host Epoxy Matrices

The degree of graphite exfoliation and edge-carboxylated layers can be controlled and balanced to design lightweight materials characterized by both low electrical percolation thresholds (EPT) and improved mechanical properties. So far, this challenging task has been undoubtedly very hard to achieve. The results presented in this paper highlight the effect of exfoliation degree and the role of edge-carboxylated graphite layers to give self-assembled structures embedded in the polymeric matrix. Graphene layers inside the matrix may serve as building blocks of complex systems that could outperform the host matrix. Improvements in electrical percolation and mechanical performance have been obtained by a synergic effect due to finely balancing the degree of exfoliation and the chemistry of graphene edges which favors the interfacial interaction between polymer and carbon layers. In particular, for epoxy-based resins including two partially exfoliated graphite samples, differing essentially in the content of carboxylated groups, the percolation threshold reduces from 3 wt% down to 0.3 wt%, as the carboxylated group content increases up to 10 wt%. Edge-carboxylated nanosheets also increase the nanofiller/epoxy matrix interaction, determining a relevant reinforcement in the elastic modulus

Potential Celiac Patients: A Model of Celiac Disease Pathogenesis

BACKGROUND AND AIM: Potential celiacs have the 'celiac type' HLA, positive anti-transglutaminase antibodies but no damage at small intestinal mucosa. Only a minority of them develops mucosal lesion. More than 40 genes were associated to Celiac Disease (CD) but we still do not know how those pathways transform a genetically predisposed individual into an affected person. The aim of the study is to explore the genetic features of Potential CD individuals. METHODS: 127 'potential' CD patients entered the study because of positive anti-tissue transglutaminase and no mucosal lesions; about 30% of those followed for four years become frankly celiac. They were genotyped for 13 polymorphisms of 'candidate genes' and compared to controls and celiacs. Moreover, 60 biopsy specimens were used for expression studies. RESULTS: Potential CD bear a lighter HLA-related risk, compared to celiac (??(2)???=???48.42; p value???=???1×10(-8)). They share most of the polymorphisms of the celiacs, but the frequency of c-REL* G allele was suggestive for a difference compared to celiac (??(2)???=???5.42; p value???=???0.02). One marker of the KIAA1109/IL-2/IL-21 candidate region differentiated potentials from celiac (rs4374642: ??2???=???7.17, p value???=???0.01). The expression of IL-21 was completely suppressed in potentials compared to celiacs (p value???=???0.02) and to controls (p value???=???0.02), in contrast IL-2, KIAA1109 and c-REL expression were over-expressed. CONCLUSIONS: Potential CD show genetic features slightly different from celiacs. Genetic and expression markers help to differentiate this condition. Potential CD is a precious biological model of the pathways leading to the small intestinal mucosal damage in genetically predisposed individuals

R-CVP versus R-CHOP versus R-FM for the initial treatment of patients with advanced-stage follicular lmphoma: results of the FOLL05 trial conducted by the Fondazione Italiana Linfomi

PURPOSE Although rituximab (R) is commonly used for patients with advanced follicular lymphoma (FL) requiring treatment, the optimal associated chemotherapy regimen has yet to be clarified. PATIENTS AND METHODS We conducted an open-label, multicenter, randomized trial among adult patients with previously untreated stages II to IV FL to compare efficacy of eight doses of R associated with eight cycles of cyclophosphamide, vincristine, and prednisone (CVP) or six cycles of cyclophosphamide, doxorubicin, vincristine, and prednisone (CHOP) or six cycles of fludarabine and mitoxantrone (FM). The principal end point of the study was time to treatment failure (TTF). Results There were 534 patients enrolled onto the study. Overall response rates were 88%, 93%, and 91% for R-CVP, R-CHOP, and R-FM, respectively (P=.247). After a median follow-up of 34 months, 3-year TTFs were 46%, 62%, and 59% for the respective treatment groups (R-CHOP v R-CVP, P=.003; R-FM v R-CVP, P=.006; R-FM v R-CHOP, P=.763). Three-year progression-free survival (PFS) rates were 52%, 68%, and 63% (overall P=.011), respectively, and 3-year overall survival was 95% for the whole series. R-FM resulted in higher rates of grade 3 to 4 neutropenia (64%) compared with R-CVP (28%) and R-CHOP (50%; P< .001). Overall, 23 second malignancies were registered during follow-up: four in R-CVP, five in R-CHOP, and 14 in R-FM. CONCLUSION In this study, R-CHOP and R-FM were superior to R-CVP in terms of 3-year TTF and PFS. In addition, R-CHOP had a better risk-benefit ratio compared with R-FM