514 research outputs found

    Quantum plasmonic waveguides: Au nanowires

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    Combining miniaturization and good operating speed is a compelling yet crucial task for our society. Plasmonic waveguides enable the possibility of carrying information at optical operating speed while maintaining the dimension of the device in the nanometer range. Here we present a theoretical study of plasmonic waveguides extending our investigation to structures so small that Quantum Size Effects (QSE) become non negligible, namely quantum plasmonic waveguides. Specifically, we demonstrate and evaluate a blue-shift in Surface Plasmon (SP) resonance energy for an ultra-thin gold nanowire

    Prevalence of Blood Types and Alloantibodies of the AB Blood Group System in Non-Pedigree Cats from Northern (Lombardy) and Southern (Sicily) Italy

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    The aims of this study were to determine the prevalence of A, B and AB blood types and alloantibodies in non-pedigree cats from two regions, one in Northern and one in Southern Italy (Lombardy and Sicily, respectively). A total of 448 samples (52.0% from Northern and 48.0% from Southern Italy) were blood typed. The prevalence of A, B and AB blood types in northern and southern cats were 91.0%, 5.2%, 3.8%, and 77.2%, 12.1% and 10.7%, respectively. The prevalence of type-A blood in southern cats was significantly lower (p = 0.0001) than in northern cats, while type-B and AB blood were significantly higher (p = 0.0085 and p = 0.0051, respectively) in Southern compared to Northern Italian cats. Alloantibodies against type-A blood were found in 94.1% of type-B cats, 11.2% of type-A cats had alloantibodies against type-B blood, while no type-AB cats had alloantibodies with no significant difference between the two Italian populations. Type-AB prevalence in non-pedigree cats in Southern Italy was the highest reported in Europe. Italian type-A cats had the lowest worldwide prevalence of alloantibodies against type-B blood. These results highlight the usefulness of regional studies to report different prevalences in feline blood types and reinforce the importance of blood typing cats before transfusions and mating

    Bevacizumab in the treatment of NSCLC: patient selection and perspectives

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    Non-small-cell lung cancer (NSCLC) represents about 85% of all lung cancers, and more than half of NSCLCs are diagnosed at an advanced stage. Chemotherapy has reached a plateau in the overall survival curve of about 10 months. Therefore, in last decade novel targeted approaches have been developed to extend survival of these patients, including antiangiogenic treatment. Vascular endothelial growth factor (VEGF) signaling pathway plays a dominant role in stimulating angiogenesis, which is the main process promoting tumor growth and metastasis. Bevacizumab (bev; Avastin®) is a recombinant humanized monoclonal antibody that neutralizes VEGF’s biologic activity through a steric blocking of its binding with VEGF receptor. Currently, bev is the only antiangiogenic agent approved for the first-line treatment of advanced or recurrent nonsquamous NSCLC in “bev-eligible� patients. The ineligibility to receive bev is related to its toxicity. In the pivotal trials of bev in NSCLC, fatal bleeding events including pulmonary hemorrhage were observed with rates higher in the chemotherapy-plus-bev group. Therefore, in order to reduce the incidence of severe pulmonary hemorrhage, numerous exclusion criteria have been characteristically applied for bev such as central tumor localization or tumor cavitation, use of anticoagulant therapy, presence of brain metastases, age of patients (elderly). Subsequent studies designed to evaluate the safety of bev have demonstrated that this agent is safe and well tolerated even in those patients subpopulations excluded from pivotal trials. This review outlines the current state-of-the-art on bev use in advanced NSCLC. It also describes patient selection and future perspectives on this antiangiogenic agent

    Fluorine effect on As diffusion in Ge

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    The enhanced diffusion of donor atoms, via a vacancy (V)-mechanism, severely affects the realization of ultrahigh doped regions in miniaturized germanium (Ge) based devices. In this work, we report a study about the effect of fluorine (F) on the diffusion of arsenic (As) in Ge and give insights on the physical mechanisms involved. With these aims we employed experiments in Ge co-implanted with F and As and density functional theory calculations. We demonstrate that the implantation of F enriches the Ge matrix in V, causing an enhanced diffusion of As within the layer amorphized by F and As implantation and subsequently regrown by solid phase epitaxy. Next to the end-of-range damaged region F forms complexes with Ge interstitials, that act as sinks for V and induce an abrupt suppression of As diffusion. The interaction of Ge interstitials with fluorine interstitials is confirmed by theoretical calculations. Finally, we prove that a possible F-As chemical interaction does not play any significant role on dopant diffusion. These results can be applied to realize abrupt ultra-shallow n-type doped regions in future generation of Ge-based devices

    Naturally occurring antibodies in cats against dog erythrocyte antigens and vice versa

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    Objectives The aim of this study was to investigate the presence of naturally occurring antibodies against canine erythrocyte antigens in cats and vice versa. The influence of canine and feline blood type on cross-match results was also studied. Methods Blood samples from 34 cats and 42 dogs were used to perform test-tube major and minor cross-match tests and blood typing. Blood from each cat was cross-matched with blood from 2-6 dogs, for a total of 111 cross-match tests. Haemolysis, macro- and/or micro-agglutination were considered markers of a positive cross-match. Results Eighty-three overall major cross-match tests were positive at 37\ub0C, 86 at room temperature and 90 at 4\ub0C. The minor cross-match tests were positive in all but two cross-matches performed at 37\ub0C, all tests performed at room temperature and all but one test performed at 4\ub0C. No cats tested totally negative at both major and minor cross-matches performed with samples from any single dog. Prevalence of warm natural antibodies against canine erythrocyte antigens was lower in type B cats than in type A cats, regardless of the blood type of donor dogs. Conclusions and relevance This study reveals a high prevalence of naturally occurring antibodies in cats against dog erythrocyte antigens and vice versa, and suggests that transfusion of cats with canine blood is not recommended as a routine procedure owing to the potential high risk of either acute severe or milder transfusion reactions

    Dog erythrocyte antigens (DEA) 1, 4, 7 and suspected naturally occurring anti-DEA 7 antibodies in italian corso dogs

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    We sought to determine the prevalence of dog erythrocyte antigen (DEA) 1, 4 and 7 and naturally occurring anti-DEA7 antibodies in Italian Corso dogs. In addition, we correlated DEAs with different epidemiologic variables, compared the prevalence of DEAs against other canine populations and assessed the risk of sensitisation and transfusion reactions (TRs) following unmatched transfusion. Blood samples from 100 Corso dogs were evaluated for DEA 1, 4, 7 and naturally occurring anti-DEA 7 antibodies. Seventy-one percent of samples were DEA 1-negative, 100% tested DEA 4-positive, and 95% tested DEA 7-negative. Suspected anti-DEA7 antibodies were found in 32% dogs. The DEA 1 and 7-negative phenotypes were significantly more common than in most canine populations. When a previously tested Italian canine population was considered as blood donors for Corso dogs, the risk of DEA 1 sensitisation using DEA 1 untyped blood was 29%, and of acute haemolytic TRs after a second untyped DEA 1-incompatible transfusion was 8%. The potential for delayed TRs between DEA 7-negative Corso dogs with suspected naturally occurring anti-DEA 7 antibodies receiving untyped DEA 7-positive blood was 11%. Conversely, when Corso dogs were blood donors for the same population, the risk of DEA 1 sensitisation was 17% and the risk of an acute haemolytic TR after a second DEA 1-incompatible blood transfusion was 3%. Corso dogs can be suitable blood donors. Additional studies are needed to clarify whether the high prevalence of naturally occurring anti-DEA 7 antibodies in this breed could increase their risk of delayed TRs when they are blood recipients

    Role of interface region on the optoelectronic properties of silicon nanocrystals embedded in SiO2

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    Light emitting silicon nanocrystals embedded in SiO2 have been investigated by x-ray absorption measurements in total electron and photoluminescence yields, by energy filtered TEM analysis and by ab-initio total energy calculations. Both experimental and theoretical results show that the interface between the silicon nanocrystals and the surrounding SiO2 is not sharp: an intermediate region of amorphous nature and of variable composition links the crystalline Si with the amorphous stoichiometric SiO2. This region plays an active role in the light emission process

    Automated microseismic event location using Master-Event Waveform Stacking

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    Published online: 17 May 2016Accurate and automated locations of microseismic events are desirable for many seismological and industrial applications. The analysis of microseismicity is particularly challenging because of weak seismic signals with low signal-to-noise ratio. Traditional location approaches rely on automated picking, based on individual seismograms, and make no use of the coherency information between signals at different stations. This strong limitation has been overcome by full-waveform location methods, which exploit the coherency of waveforms at different stations and improve the location robustness even in presence of noise. However, the performance of these methods strongly depend on the accuracy of the adopted velocity model, which is often quite rough; inaccurate models result in large location errors. We present an improved waveform stacking location method based on source-specific station corrections. Our method inherits the advantages of full-waveform location methods while strongly mitigating the dependency on the accuracy of the velocity model. With this approach the influence of an inaccurate velocity model on the results is restricted to the estimation of travel times solely within the seismogenic volume, but not for the entire source-receiver path. We finally successfully applied our new method to a realistic synthetic dataset as well as real data.Francesco Grigoli, Simone Cesca, Lars Krieger, Marius Kriegerowski, Sergio Gammaldi, Josef Horalek, Enrico Priolo and Torsten Dah

    Radiological Features of Male Breast Neoplasms: How to Improve the Management of a Rare Disease

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    The primary aim of our study was to assess the main mammographic and ultrasonographic features of invasive male breast malignancies. The secondary aim was to evaluate whether a specific radiological presentation would be associated with a worse receptor profile. Radiological images (mammography and/or ultrasound) of all patients who underwent surgery for male invasive breast cancer in our institution between 2008 and 2023 were retrospectively analyzed by two breast radiologists in consensus. All significant features of radiological presentation known in the literature were re-evaluated. Fifty-six patients were selected. The mean age at surgery of patients was 69 years (range: 35-81); in 82% of cases (46 patients), the histologic outcome was invasive ductal carcinoma. A total of 28 out of 56 (50%) patients had preoperative mammography; in 9/28 cases (32%), we found a mass with microcalcifications on mammography. The mass presented high density in 25 out of 28 patients (89%); the mass showed irregular margins in 15/28 (54%) cases. A total of 46 out of 56 patients had preoperative ultrasounds. The lesion showed a solid mass in 41/46 (89%) cases. In 5/46 patients (11%), the lesion was a mass with a mixed (partly liquid-partly solid) structure. We did not find any statistically significant correlation between major types of radiological presentation and tumor receptor arrangement. Knowledge of the main radiologic presentation patterns of malignant male breast neoplasm can help better manage this type of disease, which is rare but whose incidence is increasing
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