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For seismic assessment of wind turbines in seismically-active areas, International Standards and Guidelines allow the combination of two uncoupled analyses under environmental and earthquake loads, respectively. The separate earthquake response is generally computed including an additional aerodynamic damping in the structural model. Although some work has been done to estimate the effectiveness of uncoupled analyses for land-based wind turbines, and determine appropriate levels of aerodynamic damping, to date no similar studies have been carried out for offshore wind turbines. This paper assesses the accuracy of different time-domain implementations of uncoupled analyses for offshore wind turbines, and investigates pertinent levels of aerodynamic damping. The case study is a 5-MW wind turbine, resting on a tripod in intermediate waters. [ABSTRACT FROM AUTHOR]

Cardiac tamponade is a rare complication of coronary intervention to chronic total occlusions (CTO PCI). We report a case of persistent bleeding from a venous source following successful anterograde dissection-reentry (ADR) CTO PCI. Pericardiocentesis was performed 1 h post-procedure for tamponade. Persistent bleeding was investigated with contrast transesophageal echocardiography, pericardial manometry and blood analysis. Coronary venography revealed subtle extravasation from a cardiac vein adjacent to the site of luminal re-entry. Coronary venous perforation using ADR CTO PCI has not previously been described; however, the volume of blood loss may be significant and surgical exploration may be appropriate. [ABSTRACT FROM AUTHOR]

The aim of this study is to describe the synthesis of, relaxometric characterization of, pharmacokinetic properties of, and animal imaging experiments with a new, low molecular weight gadolinium complex with high binding affinity toward serum albumin. The gadolinium(III) chelate (B25716/1) is based on the structure of the heptadentate ligand 1,4-bis(hydroxycarbonylmethyl)-6-[bis(hydroxycarbonylmethyl)]amino-6 methylperhydro-1,4-diazepine (AAZTA) covalently conjugated to an analogue of deoxycholic acid. The study was conducted as a comparison with that of an analogous complex based on the octadentate diethylenetriaminepentaacetic acid ligand B22956/1 (whose albumin binding properties were previously assessed). The structural modification with respect to B22956/1 leads to a system that can host two coordinated water molecules in fast exchange with bulk water with potential higher efficiency as an MRI contrast agent. On interaction with human serum albumin the expected-field-independent-relaxation enhancement is not observed, possibly as a consequence of the displacement of one of the two inner-sphere water molecules of the gadolinium complex. At clinically relevant magnetic fields, however, the plasma relaxivity of B25716/1 is markedly higher than that shown by B22956/1, owing to concomitant synergistic contributions from the electronic correlation time and water molecules in the second coordination sphere. The capability of B25716/1 to enhance tumor regions in magnetic resonance images was assessed in vivo at 3 T on a xenograft tumor mouse model prepared with PC-3 cells. B25716/1 displays signal enhancements approximately double those observed for B22956/1, in agreement with the findings of the in vitro relaxivity investigations. [ABSTRACT FROM AUTHOR]

The study investigated macrolide resistance in Streptococcus pyogenes in a central Italian area from 2001 to 2006 and the possible correlation between antibiotic consumption and fluctuations of resistance percentages. Macrolide and lincosamide susceptibility of 1,419 S. pyogenes isolates was tested by Kirby Bauer method. Macrolide consumption was valuated as defined daily dose/1,000 inhabitants per day (DID), according to the World Health Organization anatomic therapeutic chemical classification. Spearman’s correlation coefficient was used to assess the association between resistance and use of (1) all macrolides pooled, (2) once daily, (3) twice daily, and (4) three times daily dosage regimens. In total, 320 strains (22.6%) were erythromycinresistant, 11.4% with the M phenotype and 11.2% with the MLS phenotype. There was a significant decrease in erythromycin resistance during the study period—from 28.1% in 2001 to 15.6% in 2006 (p < 0.01). No significant correlation was found between erythromycin resistance and local overall macrolide consumption, neither during the same year nor during the previous year. In contrast, a significant correlation was found between resistance rates and oncedaily macrolide use during the preceding 6 months in Siena r = 0.747, p = 0.008). The known greater selective effect of longacting agents could establish a pressure outcome, resulting in a specific local epidemiology during a relatively short time gap. [ABSTRACT FROM AUTHOR]

The influence of the Mg addition on the catalytic performance of a 20% Ni based SiO2/silica cloth system in the decomposition of methane for making “CO x -free” H2 in the TR range 773–873 K has been evaluated. As the Mgat/Niat ratio increases from 0.10 to 2.20 the incipient Ni–Mg-O interaction becomes stronger until the formation of Ni x Mg(1− x)O solid solution. The presence of Mg2+ ions allows a higher carbon capacity (C/Ni, number of CH4 molecules converted per Ni atom until complete catalyst deactivation) and consequently a higher H2 productivity of the Ni based systems which results in a smoothing effect of the unavoidable declining activity trend even if it does not affect the tip growth coking mechanism. [ABSTRACT FROM AUTHOR]

Synthesis of liquid oxygenates from light alkanes (C1--C3) is achieved in a multifunctional three-phase catalytic membrane reactor (3PCMR) operating under mild conditions (TR, 80-120 °C; PR, 140 kPa). The features of superacid catalytic membranes mediated by the Men+/H2O2 Fenton system in activating C1-C3 alkanes are presented. The effect of operating conditions ([H2O2], [Men+]) on the catalyst activity is outlined. A general reaction pathway accounting for the activation of the CH bond of the alkane molecule on the superacid sites and the subsequent reaction of the activated alkane with primary reactive intermediates, generated from the Men+/H2O2 system, is proposed. The suitability of the 3PCMR in enabling simultaneous reaction and product separation is discussed. [ABSTRACT FROM AUTHOR]

The aim of this study was to review the histology of the upper-pole segment in patients with duplex-system ectopic ureterocele (DEU) to determine if less aggressive surgery is justified in prenatally-diagnosed cases. The study included 15 consecutive patients with DEU treated between 1991 and 1999. The diagnosis was made according to the criteria of the Section on Urology of the American Academy of Pediatrics. The histology specimens were assessed for dysplastic, inflammatory, and obstructive changes. All 15 patients were surgically treated by heminephro-ureterectomy and the surgical specimens were histologically examined. Nine cases were diagnosed prenatally; the histology of the upper-pole segment in these patients showed segmental renal microcystic dysplasia, chondroid metaplasic islands, and an inflammatory tubulointerstitial nephropathy in 6 (66.6%) and nephroblastomatosis in 2 (22.2%). The histology of the 6 postnatally-diagnosed patients showed segmental multicystic renal dysplasia, inflammatory tubulo-interstitial nephropathy, and segmental parenchymal scars. The upper-pole histology of the prenatally-diagnosed patients did not show any evidence of reversible histologic changes. Considering this findings and the good outcome of patients treated with upper-pole nephroureterectomy, less aggressive surgery with preservation of the upper pole does not seem justified. [ABSTRACT FROM AUTHOR]

A preparation method of highly effective methane to formaldehyde partial oxidation (MPO) FeOx/SiO2 catalysts (Fe 0.09--0.43 wt%) is reported, based on “adsorption-precipitation” (ADS/PRC) of FeII ions under controlled conditions. The performance of ADS/PRC catalysts in the MPO reaction at 650 °C has been compared with that of conventional systems prepared by “incipient wetness” (INC/WET) of silica carriers with aqueous solutions of FeIII. The ADS/PRC method, likely enabling a higher dispersion of the active phase, provides very effective MPO catalysts featuring CH4 turnover frequency (TOF) and HCHO productivity (STYHCHO) values larger than those of the counterpart INC/WET systems. [ABSTRACT FROM AUTHOR]

The authors have studied the histochemical pattern of Peanut lectin (PNA) binding sites in lungs of seven newborns with hyaline membrane disease (HMD) and ten controls. The alveolar lining layer was positive in HMD and no changes in the PNA pattern was noted after neuraminidase digestion. Hyaline membranes were generally unstained but occasional reactivity was encountered in some parts. No reaction with PNA was observed in control lungs, but positivity was seen after neuraminidase pretreatment. Our histochemical data document the presence of accessible galactosyl residues with absence of terminal sialic acid in the alveolar lining layer of newborns with HMD. The authors suggest that PNA reactivity in HMD reflects an histochemical feature described in fetal lungs at the pseudoglandular and canalicular stages. [ABSTRACT FROM AUTHOR]

The structure of the supported phase of differently loaded VO /SiO and MoO /SiO catalysts and the interaction of the surface species with the carrier were studied by DR UV-Vis and FT-IR spectroscopy. In the case of the VO /SiO systems, an evolution from isolated to clusterized tetrahedral (Td) V51 containing species was observed passing from low to high loading, whereas complex polymeric structures containing Mo ions in octahedral coordination were found to be overwhelmingly present in MoO catalysts at any loading. The isolated V (Td ) species are suggested to be responsible for the high activity of low-loaded VO /SiO samples, while the poor catalytic performances of MoO /SiO indicate that polymolybdate species are almost inactive in the partial oxidation of methane to formaldehyde. [ABSTRACT FROM AUTHOR]

The authors have studied kidney tissues from two cases of Congenital Nephrotic Syndrome of Finnish Type (CNS:FT), two cases of infantile polycystic disease and five normal newborns using Peanut (PNA) and Lotus Tetragonolobus (LTA) peroxidase-labeled lectins. In CNS:FT a positive reaction for LTA has been documented at the luminal surface of the microcysts, while no staining was observed with PNA. In infantile polycystic disease the cysts were stained by PNA, whereas LTA binds selectively proximal undilated tubules. In normal kidney distal tubules as well as collecting ducts and proximal tubules were stained by PNA and LTA respectively. The results suggest that in CNS:FT microcystic transformation of the kidney can originate from proximal tubules according to microdissection studies elsewhere reported. [ABSTRACT FROM AUTHOR]

CO adsorption on high loading Ni/MgO samples treated at 800 and 900°C has been studied by using IR spectroscopy. Linear and bridged monocarbonyls are produced under low CO pressure and the Boudouard reaction occurs producing C, adsorbed on the metal particles, and CO, stabilized on the MgO matrix. Effects of hydrogen and carbon on surface reactivity have been studied. The morphology of the catalysts and of carbonaceous deposits produced by heating in CO at high temperature are examined by HRTEM. [ABSTRACT FROM AUTHOR]

The influence of the Mg addition on the catalytic performance of a 20% Ni based SiO2/silica cloth system in the decomposition of methane for making “CO x -free” H2 in the TR range 773–873 K has been evaluated. As the Mgat/Niat ratio increases from 0.10 to 2.20 the incipient Ni–Mg-O interaction becomes stronger until the formation of Ni x Mg(1− x)O solid solution. The presence of Mg2+ ions allows a higher carbon capacity (C/Ni, number of CH4 molecules converted per Ni atom until complete catalyst deactivation) and consequently a higher H2 productivity of the Ni based systems which results in a smoothing effect of the unavoidable declining activity trend even if it does not affect the tip growth coking mechanism. [ABSTRACT FROM AUTHOR]