107 research outputs found
A new paradigm in functionally graded adhesives
To fully realize the benefits of advanced composites, mechanical fasteners must be supplanted by more efficient technologies such as adhesive bonding. The promise of functionally graded adhesives to provide particularly high levels of performance in this context has been recognized for decades, but a means of generating stable, high performance adhesive joints with arbitrary gradations in mechanical properties has proved elusive.
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Acoustic pharyngometry: clinical and instrumental correlations in sleep disorders
Summary Matteo Gelardi 1 , Alessandro Maselli del Giudice 2 , Francesco Cariti 3 , Michele Cassano 4 , Aline Castelante Farras 5 , Maria Luisa Fiorella 6 , Pasquale Cassano 7 1 ENT specialist (Physician of the Bari University Otorhinolaryngology Department - Italy) 2 Physician (ENT Resident - Bari University - Italy) 3 Physician (ENT Resident - Bari University - Italy) 4 ENT specialist (Researcher of the Foggia University Otorhinolaryngology Department - Italy) 5 ENT specialist (Fellow of the Foggia University Otorhinolaryngology Department - Italy) 6 ENT specialist (Researcher of the Bari University Otorhinolaryngology Department - Italy) 7 ENT and Audiology specialist (Head of the Foggia University Otorhinolaryngology Department and Full Professor of Otorhinolaryngology at Foggia University - Italy)Bari University - Italy; Foggia University - ItalyDr. Michele Cassano Via: Crispi 34/C CEP: 70123 Bari - Italy. Telephone: 00xx39-080-5235508/ 00xx39-3388105268 Fax: 00xx39-080-5211318. Dra. Aline Castelante Farras Rua Sete de Setembro, 676 Centro Vila Velha - ES Telefone: 27-32393661 E-mail: [email protected] [email protected] Paper submitted to the ABORL-CCF SGP (Management Publications System) on July 29th, 2005 and accepted for publication on November 3th, 2006. cod. 567
New developments in dual cure epoxies
Direct write 3D printing provides an exciting new means of generating novel structures from thermosetting resins via an additive approach. Initial efforts along these lines demonstrated the preparation of homogenous, high quality parts. More recent work has shown that it is possible to modulate the properties of these parts locally through changes in orientation of high aspect ratio fillers.
In this work, we present complementary developments related to resin chemistry that should provide practitioners of direct write 3D printing with additional options as far as the realization of functional gradations is concerned. This is accomplished via the creation of so-called “dual cure” resins. Here this term refers to materials that undergo thermal cure in a similar fashion to many conventional resins. Then, in a second step, the selective exposure of these materials to high energy radiation (gamma rays, electrons, etc.) results in further increases in local crosslink density, altering thermomechanical performance and providing a means of inducing arbitrary gradations in properties in a post-processing step.
A number of different families of dual cure resins have been explored and are presented here, as well as data concerning changes in thermal and mechanical performance as a function of the details of the dual curing process. Preliminary efforts giving evidence of the generation of stable functional gradations in practice are also described. Ongoing and future efforts are focused on the optimization of these systems and the incorporation of their cure-dependent mechanical behavior into simulations in order to enable design optimization
Estimate of tissue composition in malignant and benign breast lesions by time-domain optical mammography
partially_open10noThe optical characterization of
malignant and benign breast
lesions is presented. Time-resolved transmittance measurements were
performed in the 630-1060 nm range by means of a 7-wavelength optical
mammograph, providing both imaging and spectroscopy information. A
total of 62 lesions were analyzed, including 33 malignant and 29 benign
lesions. The characterization of breast lesions was performed applying a
perturbation model based on the high-order calculation of the pathlength of
photons inside the lesion, which led to the assessment of oxy- and deoxy-
hemoglobin, lipids, water and collagen concentrations. Significant
variations between tumor and healthy tissue were observed in terms of both
absorption properties and constituents co
ncentration. In particular, benign
lesions and tumors show a statistically significant discrimination in terms of
absorption at several wavelengths and also in terms of oxy-hemoglobin and
collagen content.G. Quarto; L. Spinelli; A. Pifferi; A. Torricelli; R. Cubeddu; F. Abbate;
N. Balestreri; S. Menna; E. Cassano; P. TaroniQuarto, Giovanna; Spinelli, Lorenzo; Pifferi, ANTONIO GIOVANNI; Torricelli, Alessandro; Cubeddu, Rinaldo; F., Abbate; N., Balestreri; S., Menna; E., Cassano; Taroni, Paol
A faringometria acústica: correlações clínico-instrumentais nos distúrbios do sono
A faringometria acústica representa um método atual baseado no principio físico da reflexão acústica, útil à análise volumétrica do espaço orofaringolaringotraqueal. OBJETIVO: Este estudo se propõe a avaliar as variações dos parâmetros faringométricos em indivíduos portadores de distúrbios respiratórios do sono (DRS), para estabelecer uma relação entre as variações morfovolumétricas do espaço orofaringolaríngeo e a existência e gravidade da patologia. FORMA DE ESTUDO: Clínico e experimental. MATERIAL E MÉTODO: Foram examinados 110 pacientes, 70 com DRS e 40 normais, durante o período de Junho/04 a Junho/05. Todos os pacientes foram submetidos à faringometria acústica que permitiu uma avaliação da área oro e hipofaríngea através de um gráfico explicativo. RESULTADOS: Os parâmetros obtidos nos pacientes com DRS mostraram uma importante diferença com respeito ao grupo controle, principalmente na amplitude da I onda (significantemente menor nos pacientes com macroglossia), na extensão do segmento OF, na amplitude do segmento OF e na área hipofaríngea. COLCLUSÃO: A faringometria acústica, mesmo não sendo uma técnica padronizada, pode auxiliar no diagnóstico das síndromes obstrutivas do sono, na localização dos possíveis pontos de obstrução e da gravidade da patologia, e no monitoramento dos pacientes submetidos a cirurgias desobstrutivas das vias aéreas superiores
Complete Metabolic Response with Recanalization of Portal Vein Tumor Thrombosis after Sunitinib in a Patient with Advanced Hepatocellular Carcinoma
The prognosis of patients with advanced hepatocellular carcinoma (HCC) is very poor. The outcome of these patients is particularly bleak when the disease is complicated by portal vein tumor thrombosis (PVTT), since the increased portal pressure often causes serious gastrointestinal bleedings. Before the introduction of sorafenib (SOR), a tyrosine kinase inhibitor, no effective treatment was available for patients with advanced disease. SOR is now considered the standard treatment even for patients with tumor thrombosis, although the well-known interference between tyrosine kinase inhibitors and the coagulation pathway calls for caution against their use in this setting. Here, we report the case of a 74-year-old male patient with advanced HCC and PVTT treated with sunitinib (SUN), another multikinase inhibitor. During the third cycle, our patient experienced a life-threatening hematemesis with hemorrhagic shock that required intensive care treatment and SUN discontinuation. However, he completely recovered, and the PET/CT scan performed 1 year after the adverse effect demonstrated no evidence of the tumor together with portal vein recanalization. The short course of SUN causing both tumor response and gastrointestinal bleeding warrants further studies on the effectiveness of SUN in this setting as well as on the duration of treatment with multikinase inhibitors in patients with tumor thrombosis
Operator learning curve for transradial liver cancer embolization: implications for the initiation of a transradial access program
PURPOSEWe aimed to analyze transradial access (TRA) learning curve on patients undergoing hepatic chemoembolization, investigating the relationship between procedural volumes and various benchmarks of procedural success.METHODSWe enrolled 60 consecutive patients who received two unilobar hepatic chemoembolizations within a 4-week interval performed by a single interventional radiologist, highly-trained in conventional transfemoral access (TFA) procedures, but without any previous practical experience in TRA procedures and with a preliminary 2-day theoretical training only. Consecutive patients were prospectively enrolled and analyzed in 3 groups: A (cases 1 to 20), B (cases 21 to 40), and C (cases 41 to 60). All patients underwent one hepatic chemoembolization using TRA and the other one using TFA in random order. All TFA procedures performed by the same operator in the same series of patients were considered as the control group. Primary endpoint was to analyze the relationship between TRA procedure operator experience and benchmarks of procedural success, to define the optimal procedural learning curve.RESULTSTechnical success was obtained in all patients, with a crossover rate (radial to femoral access) of 0%. An association between incremental TRA operator experience (in terms of performed procedures) and decrease of preparation, puncture, fluoroscopy, and total examination times was observed. Similarly, inverse associations between incremental TRA operator experience and contrast medium (CM) volumes (P < 0.001) and radiation dose (RD) values (in terms of RAK - Reference Air Kerma) (P < 0.001) were also observed. Compared with TFA, CM volumes and RD values were significantly higher only in group A (cases 1–20). Procedure success remained high in all TRA groups and no significant association between TRA incremental experience and postprocedural outcomes was found. Higher postprocedural complaints at the access route and more limitations in performing basic activities were recorded after TFA vs. TRA (P < 0.001).CONCLUSIONTRA catheterizations can be safely performed in patients treated for liver cancer embolization after a relatively short training in controlled conditions and with a better performance in comparison with TFA. Operator proficiency improves with greater TRA experience, with a threshold needed to overcome the learning curve represented by about 20 procedures
Global exposure of population and land‐use to meteorological droughts under different warming levels and SSPs: a CORDEX‐based study
Global warming is likely to cause a progressive drought increase in some regions, but how population and natural resources will be affected is still underexplored. This study focuses on global population, forests, croplands and pastures exposure to meteorological drought hazard in the 21st century, expressed as frequency and severity of drought events. As input, we use a large ensemble of climate simulations from the Coordinated Regional Climate Downscaling Experiment (CORDEX), population projections from the NASA-SEDAC dataset and land-use projections from the Land-Use Harmonization 2 project for 1981–2100. The exposure to drought hazard is presented for five Shared Socioeconomic Pathways (SSP1-SSP5) at four Global Warming Levels (GWLs: 1.5°C to 4°C). Results show that considering only Standardized Precipitation Index (SPI; based on precipitation), the SSP3 at GWL4 projects the largest fraction of the global population (14%) to experience an increase in drought frequency and severity (versus 1981–2010), with this value increasing to 60% if temperature is considered (indirectly included in the Standardized Precipitation-Evapotranspiration Index, SPEI). With SPEI, considering the highest GWL for each SSP, 8 (for SSP2, SSP4, SSP5) and 11 (SSP3) billion people, that is, more than 90%, will be affected by at least one unprecedented drought. For SSP5 at GWL4, approximately 2 × 10 km of forests and croplands (respectively, 6% and 11%) and 1.5 × 10 km of pastures (19%) will be exposed to increased drought frequency and severity according to SPI, but for SPEI this extent will rise to 17 × 10 km of forests (49%), 6 × 10 km of pastures (78%) and 12 × 10 km of croplands (67%), being mid-latitudes the most affected. The projected likely increase of drought frequency and severity significantly increases population and land-use exposure to drought, even at low GWLs, thus extensive mitigation and adaptation efforts are needed to avoid the most severe impacts of climate change
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