Search results for "pair"
showing 10 items of 2908 documents
Abdominal Compartment Syndrome (ACS) After Surgical Abdominal Aortic Aneurysm (AAA) Repair
2009
Hypotensive Hemostasis in Patients Presenting with Ruptured Aortic Aneurysm
2017
Hypotensive hemostasis in aortic rupture has been showed to be feasible and advantageous, especially in trauma patients. To date, there are no randomized studies on hypotensive hemostasis in patients with ruptured abdominal aortic aneurysm (rAAA), but observational studies indicate similar advantages when hypotensive hemostasis is used for endovascular aneurysm repair (EVAR) as in trauma patients. Actually, in EVAR for rAAA, a target systolic blood pressure of 90 mmHg or even lower is considered safe in conscious patients. Fluids should be administrated judiciously with the sole aim of maintaining adequate cardiac output and tissue oxygenation, whereas vasoactive pressors or dilatators may …
Achilles tendon rupture: percutaneous repairing
2011
Active repair technology applied to delaminated composite structures
2009
The main target of the present paper is represented by the fracture mechanics charac-terization of delaminated composite structures actively repaired through piezoelectric patches. A boundary element code, formulated for anisotropic piezoelectric solids, including, as limiting case, the applicability to linear elastic anisotropic materials has been then imple-mented. The modeling of the delaminated composite structures as well as of the assembled structures, made of the damaged components and the patches, has been achieved through the multidomain technique. Moreover, to take into account for the adhesive layer between the host structures and the piezoelectric patches, a "spring-model" has b…
BE contact analysis of delamination cracks actively repaired trhough piezoelectric active patches
2009
Analysis of piezoelectric active patches performances by boundary element techniques
2008
This paper presents the analysis of active piezoelectric patches for cracked structures by Boundary Element Method. A two dimensional boundary integral formulation based on the multidomain technique is used to model cracks and to assemble the multi-layered piezoelectric patches to the host damaged structures. The fracture mechanics behavior of the repaired structures is analyzed for both perfect and imperfect interface between patches and host beams. The imperfect interface, representing the adhesive between two different layers, is modeled by using a “Spring Model” that involves linear relationships between the interface tractions, in normal and tangential directions, and the respective di…
Solubility and acid-base properties and activity coefficients of chitosan in different ionic media and at different ionic strengths, at T=25°C
2009
Studies on the acid-base properties and solubility of a polyammonium polyelectrolyte (chitosan) with different molecular weights (MW 310 and 50 kDa), were performed at T=25 °C, in the pH range 2.5–7. The protonation of chitosan was investigated by potentiometry ([H+]-glass electrode) in NaCl, NaNO3 and mixed NaNO3+Na2SO4 ionic media, at different ionic strengths. Protonation constants were calculated as a function of dissociation degree α by means of two different models, namely, a simple linear model and the modified Henderson–Hasselbalch equation. Experimental data were also fitted using a model independent of α (Diprotic-like model), according to which the acid-base properties can be sim…
Hydrolysis and chemical speciation of dioxouranium(VI) ion in aqueous media simulating the major ion composition of seawater
2004
Abstract The hydrolysis and chemical speciation of the dioxouranium(VI) ion at 25 °C was studied in a number of binary electrolytes (LiCl, NaCl, MgCl2, CaCl2, Na2SO4) and some mixtures (NaCl–Na2SO4, NaNO3–Na2SO4, CaCl2–MgCl2) as well as artificial seawater (SSWE) as a function of ionic strength. The results in LiCl, CaCl2 and MgCl2 solutions confirmed the formation of (UO2)2(OH)22+, (UO2)3(OH)42+, (UO2)3(OH)5+ and (UO2)3(OH)7− species (at I=0 mol l−1: log Tβ22=−5.76, log Tβ34=−11.82, log Tβ35=−15.89 and log Tβ37=−29.26). For NaNO3, NaCl and artificial seawater the hydrolysis constant for the formation of the UO2(OH)+ species was also determined (at I=0 mol l−1: log Tβ11=−5.19). The results …
The Right Job and the Job Right: Novelty, Impact and Journal Stratification in Science
2018
Though Science is traditionally associated with creative behavior, concerns have been raised on its professional procedures being sufficiently open to innovative research. Thanks to a new measurement of novelty based on the frequencies of pairwise combinations of article keywords calculated on the set of all research articles published from 1999 to 2013 in the journals referenced by the WoS (more than ten million papers), we find no evidence of shrinking novelty in science over that period. Novel contributions are more often performed in larger teams that span more institutional boundaries and geographic areas. High novelty increases citations by more than forty percent and the odds of a “b…