SUMMARYNear-fault ground motions are characterized by long-period horizontal pulses and high values of the ratio between the peak value of the vertical acceleration, PGA V , and the analogous value of the horizontal acceleration, PGA H , which can become critical for base-isolated (BI) structures. The objective of the present work is to check the effectiveness of the base isolation of framed buildings when using HighDamping-Rubber Bearings (HDRBs), taking into consideration the combined effects of the horizontal and vertical components of near-fault ground motions. To this end, a numerical investigation is carried out with reference to BI reinforced concrete buildings designed according to the European seismic code (Eurocode 8). The design of the test structures is carried out in a high-risk region considering (besides the gravity loads) the horizontal seismic loads acting alone or in combination with the vertical ones and assuming different values of the ratio between the vertical and horizontal stiffnesses of the HDRBs. The nonlinear seismic analysis is performed using a step-by-step procedure based on a two-parameter implicit integration scheme and an initial-stress-like iterative procedure. At each step of the analysis, plastic conditions are checked at the potential critical sections of the girders (i.e. end sections of the sub-elements in which a girder is discretized) and columns (i.e. end sections), where a bilinear moment-curvature law is adopted; the effect of the axial load on the ultimate bending moment (M-N interaction) of the columns is also taken into account. The response of an HDRB is simulated by a model with variable stiffness properties in the horizontal and vertical directions, depending on the axial force and lateral deformation, and linear viscous damping.

Extremely high plasma triglyceride (TG) concentration is a recognized risk factor for acute pancreatitis (AP). In order to evaluate the therapeutic efficacy of plasma-exchange plasmapheresis in treating patients with severe hypertriglyceridemia (sHTG), 17 patients who had not responded to conventional medical therapy (fat-free diet plus pharmaceutical interventions) were referred for therapeutic plasma exchange (TPE) in a multicenter frame case series study. Two hundred seventeen TPE sessions were performed, and therapy is ongoing for five (30%) of the patients. After treatment, the mean plasma TG and total cholesterol concentrations were significantly reduced from 1929 and 510 mg/dL, to 762 and 227 mg/dL, respectively (P < or = 0.001 in both cases). In most cases, the interval between treatments was related to the clinical presentation and individual circumstances. The removal of TG-rich lipoproteins prevented relapses of AP. In this case series, TPE is confirmed as a safe and reliable method for treating patients with refractory sHTG when a severe complication, such as AP, is clinically demonstrated or can be actively prevented. Therefore, in cases where standard medical approaches fail to promote the clearance of TGs from plasma and a high risk of first or second hypertriglyceridemic pancreatitis persists, TPE provides a therapeutic option for preventing life-threatening sHTG.

We have previously shown that hemopoietic stem cell transplant (HSCT) recipients can be stratified on day þ 7 as having low, intermediate or a high risk of transplantrelated mortality (TRM). With the aim of reducing TRM and GVHD, intermediate and high-risk patients (n ¼ 170) were randomized to receive anti-thymocyte globulin (ATG, thymoglobuline) on day þ 7 (n ¼ 84) or no treatment (n ¼ 86) (controls). There was a reduction of TRM from 35% in controls to 29% in ATG patients (P ¼ 0.3), of acute GVHD III-IV from 15 to 5% (P ¼ 0.02) and of chronic GVHD from 26 to 11% (P ¼ 0.03); survival was comparable. The predictive value of the day þ 7 score on TRM was confirmed for controls (19 vs 42% for intermediate vs high risk, respectively, P ¼ 0.03), whereas ATG abrogated this predictive effect (29 vs 29%). ATG reduced GVHD (P ¼ 0.006) in high-risk patients, but not in patients with an intermediate risk.In conclusion, we confirm that TRM can be predicted on the basis of day þ 7 laboratory values, after alternative donor HSCT; in high-, but not intermediate-risk patients, the administration of ATG on day þ 7 reduces GVHD. These results may represent a platform for risk-adapted post transplant immune modulation.

The insertion of damped braces proves to be very effective for enhancing the performance of a framed building under seismic loads. For a widespread application of this technique suitable design procedures are needed. In this paper a design procedure which aims to proportion damped braces to attain a designated performance level of the structure, for a specific level of seismic intensity, is proposed. In particular, a proportional stiffness criterion, which assumes the elastic lateral storey-stiffness due to the braces proportional to that of the unbraced frame, is combined with the displacement-based design, in which the design starts from a target deformation. To check the effectiveness and reliability of the design procedure, a six-storey reinforced concrete plane frame, representative of a medium-rise symmetric framed building, is considered as primary structure. This, designed in a mediumrisk seismic region, has to be retrofitted as in a high-risk seismic region by the insertion of braces equipped with either metallic-yielding dampers or viscoelastic ones. Nonlinear dynamic analyses of unbraced and damped braced frames are carried out, under real (set A) and artificially generated (set B) ground motions, by a step-by-step procedure. Frame members and hysteretic dampers are idealized by bilinear models, while the viscoelastic dampers are idealized by a six-element generalized model describing the variation of the mechanical properties depending on the frequency, at a given temperature.

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