Parametrical analysis of the degradation of gas phase trichloroetylene in a photocatalytic reactor with titanium dioxide coated glass fiber meshes

El estudio de la degradación de Tricloroetileno (TCE) en aire en un reactor fotocatalítico con dióxido de titanio depositado sobre un lecho fijo ha permitido obtener en un trabajo previo, una expresión cinética que contempla la influencia de la concentración del contaminante, la Radiación Incidente y el efecto competitivo del agua y el TCE por los sitios activos del catalizador(1). En este trabajo se resuelve numéricamente la ecuación diferencial en derivadas parciales de transferencia de materia en un reactor fotocatalítico constituido por mallas de vidrio con dióxido de titanio depositado e irradiadas mediante radiación UV. Esta solución numérica evita la introducción de un coeficiente de transferencia de materia sobre la superficie catalítica, obtenido a partir de correlaciones típicas para interfaces gas-sólido bajo el régimen de flujo correspondiente(2,3). Modificando los parámetros relevantes del sistema resulta posible simular el comportamiento del reactor bajo distintas condiciones de operación.The analysis of Trichloroethylene (TCE) degradation in air in a photocatalytic reactor with titanium dioxide coated on a fixed bed has provided in a previous work, a Kinetic expression which takes into account the pollutant concentration, the Incident Radiation and the competition between water and TCE for the photocatalytic active sites(1). In this work, the numerical solution of the mass transfer partial differential equation in a photocatalytic reactor with glass fiber meshes coated with titanium dioxide and UV irradiated is accomplished. This numerical solution avoids the use of a mass transfer coefficient over the catalytic surface, obtained by means of typical correlations for gas-solid interfaces under the correspondent flow regime(2,3). Changing the relevant system parameters, it is possible to simulate the reactor behaviour under different operation conditions.Fil: Esterkin, C. R.. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Santa Fe. Instituto de Desarrollo Tecnológico para la Industria Química. Universidad Nacional del Litoral. Instituto de Desarrollo Tecnológico para la Industria Química; ArgentinaFil: Negro, Antonio Carlos. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Santa Fe. Instituto de Desarrollo Tecnológico para la Industria Química. Universidad Nacional del Litoral. Instituto de Desarrollo Tecnológico para la Industria Química; ArgentinaFil: Cassano, Alberto Enrique. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Santa Fe. Instituto de Desarrollo Tecnológico para la Industria Química. Universidad Nacional del Litoral. Instituto de Desarrollo Tecnológico para la Industria Química; ArgentinaFil: Alfano, Orlando Mario. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Santa Fe. Instituto de Desarrollo Tecnológico para la Industria Química. Universidad Nacional del Litoral. Instituto de Desarrollo Tecnológico para la Industria Química; Argentin

NEMA NU 4-2008 Performance measurements of two commercial small-animal PET scanners: clearPET and rPEAT-1

In this work, we compare two commercial positron emission tomography (PET) scanners installed at CIEMAT (Madrid, Spain): the ClearPET and the rPET-1. These systems have significant geometrical differences, such as the axial field of view (110 mm on ClearPET versus 45.6 mm on rPET-1), the configuration of the detectors (whole ring on ClearPET versus one pair of planar blocks on rPET-1) and the use of an axial shift between ClearPET detector modules.We used an assessment procedure that fulfilled the recommendations of the National Electrical Manufacturers Association (NEMA) NU 4-2008 standard. The methodology includes studies of spatial resolution, sensitivity, scatter fraction, count losses and image quality. Our experiments showed a central spatial resolution of 1.5 mm (transaxial), 3.2 mm (axial) for the ClearPET and 1.5 mm (transaxial), 1.6 mm (axial) for the rPET-1, with a small variation across the transverse axis on both scanners (~1 mm). The absolute sensitivity at the centre of the field of view was 4.7% for the ClearPET and 1.0% for the rPET-1. The peak noise equivalent counting rate for the mouse-sized phantom was 73.4 kcps reached at 0.51 MBq/mL on the ClearPET and 29.2 kcps at 1.35 MBq/mL on the rPET-1. The recovery coefficients measured using the image quality phantom ranged from 0.11 to 0.89 on the ClearPET and from 0.14 to 0.81 on the rPET-1. The overall performance shows that both the ClearPET and the rPET-1 systems are very suitable for preclinical research and imaging of small animalsPublicad

Performance comparison of two commercial small animal PET scanners: clearPETTM and rPET-1TM

Proceeding of: 2008 IEEE Nuclear Science Symposium Conference Record (NSS '08), Dresden, Germany, 19-25 October 2008It is usually difficult to compare different designs of Positron Emission Tomography (PET) small-animal scanners because of the disparity of measurements protocols. In this work we compare two commercial PET scanners installed at ClEMAT (Madrid, Spain): the ClearPET and the rPET-I, using an assessment procedure that fulfilled the recommendations of the new NEMA NU 4-2008 standard to evaluate small animal PET systems, including spatial resolution, sensitivity, scatter fraction and count losses studies. The scanners evaluated have significant geometrical differences, like the axial field of view (110 mm on ClearPET versus 45.6 mm on rPET-l), the configuration of the detectors (one pair of planar blocks on rPET-I, versus whole ring detectors on ClearPET) and the use of an axial shift between ClearPET module detectors. Our experiments showed a FWHM (FOV center, averaged over the three axes) of 1.98 mm for the rPET-1 and 2.15 rom for the ClearPET, with a small variation across the transverse axis on both scanners «1 rom). The absolute sensitivity was 1.0% per detector pair for rPET-I and 4.70/0 for ClearPET. Regarding count losses studies, the obtained peak NEC rate is 73.4 kcps at 0.51 MBq/ml for the ClearPET and 29.2 kcps at 1.35 MBq/ml for the rPET-1, considering a NEMA mouse-like phantom

Crown Walls in Mass and Reinforced Concrete: The Way to Aesthetics in Maritime Works

Maritime works are characterized by their remarkable size, length, depth and extraordinarily great demand for natural or artificial materials. To this effect, despite functional designs or the ultimate limit state, a breakwater crown wall can increase the overall effectiveness of the structure in limiting wave overtopping. It will contribute to a reduction of volume of material required and hence the cost to achieve a given level of performance depending on the precautions to be taken on the basis of the critical discharges for functional safety (vehicles, pedestrian and buildings) and structural safety (embankment and revetment seawalls), amongst others. In many cases, bulky mass-concrete elements are designed without any steel reinforcement. Sometimes this effect causes cracking problems in large volumes. The step to slender reinforced concrete elements may take a leap to the aesthetic factor and visual landscape integration in maritime works. In addition, the use of other materials, shapes and colours can bring breakwaters and crown walls to life by creating new functions for maritime works such as a promenade, relaxation or visual enjoyment areas. The aim of this article is to reflect on the issue of bulky mass concrete elements or rebars in slender reinforced concrete crown walls and how the use of these slender elements can bring with it excellent artistic developments as well as the use of other materials in mass concrete sloping, vertical and composite breakwaters and their crown walls. Some breakwaters are no longer just mere defence works but are becoming pieces of art

Analisi di costo efficacia nella terapia della BPCO

Current practice guidelines for the treatment of COPD recommend the use of combined inhaled corticosteroids and long-acting bronchodilators in severe and very severe patients (GOLD stages III and IV). OBJECTIVES: To analyze the economical and clinical impact of this recommendation, the affordability of its widespread application, as well as the relative pharmacoeconomical performance of the available options for severe and very severe COPD in Italy. METHODS: Published data on the Italian COPD population were fitted in a disease progression model based on a Markov chain representing severity stages and death. Alternative therapeutic options (salmeterol/ fluticasone - SF, formoterol/budesonide - FB, salmeterol alone - S, fluticasone alone - F and control - C) were represented as competing arms in a decision tree. Efficacy data from international trials were expressed in terms of risk reduction. Clinical parameters used were number of exacerbations and symptom-free days. Direct and indirect costs were considered and valued according to present prices and tarifs. The analyses were conducted from National Health System, societal and patient perspectives with time horizons of 1,5, and 10 years, and lifelong. RESULTS: The yearly total direct costs of treating COPD patients in Italy is estimated in approximately 7 billion Euro, with a mean cost/patient/year around 2,400 Euro. Mean survival of the cohort is 11,5 years. The C and F strategies are dominated (i.e. are associated with worse outcomes and higher costs) by all alternatives. S/F and F/B are the most effective strategies, with a slight clinical superiority of the latter, but are also marginally more expensive than S. Incremental cost/effectiveness of S/F vs. S is 679,55 Euro/avoided exacerbation and 3,31Euro/gained symptom-free day. CONCLUSIONS: The recommended use of combined inhaled corticosteroids and long-acting bronchodilators for severe and very severe COPD patients, as compared with current practice, has the potential of improving clinical outcomes without increasing health care costs

KDC1, a Novel Carrot Root Hair K+Channel CLONING, CHARACTERIZATION, AND EXPRESSION IN MAMMALIAN CELLS

Potassium is an essential nutrient which plays an important role in many aspects of plant growth and development. Plants have developed a number of highly specific mechanisms to take up potassium from the soil; these include the expression of K+ transporters and potassium channels in root cells. Despite the fact that root epidermal and hair cells are in direct contact with the soil, the role of these tissues in K+uptake is not well understood. Here we report the molecular cloning and functional characterization of a novel potassium channel KDC1 which forms part of a new subfamily of plant Kinchannels. Kdc1 was isolated from carrot root RNA andin situ hybridization experiments show Kdc1 to be highly expressed in root hair cells. Expressing the KDC1 protein in Chinese hamster ovary cells identified it as a voltage and pH-dependent inwardly rectifying potassium channel. An electrophysiological analysis of carrot root hair protoplasts confirmed the biophysical properties of the Kdc1 gene product (KDC1) in the heterologous expression system. KDC1 thus represents a major K+ uptake channel in carrot root hair cells

Effect of Erdosteine on COPD Exacerbations in COPD Patients with Moderate Airflow Limitation

Background: The RESTORE study, a multi-national randomized, placebo-controlled study, showed that erdosteine - a muco-active antioxidant that modulates bacterial adhesiveness - reduced the rate and duration of exacerbations in moderate and severe COPD with a history of exacerbations. How much benefit patients with less severe disease experience when taking this drug remains unclear. Methods: This post hoc analysis of the 254 RESTORE participants with spirometrically-defined moderate COPD (post-bronchodilator forced expiratory volume in 1 second [FEV1] 50\u201279% predicted) examined exacerbation rate and duration, time to first exacerbation, and exacerbation-free time. Data were analyzed using descriptive statistics and comparisons between treatment groups used Wilcoxon rank-sum tests, Mann-Whitney U-tests, or log rank tests. Results: Patients with moderate COPD received erdosteine 300 mg twice daily (n=126) or placebo (n=128) added to usual COPD therapy for 12 months. During this time, there were 53 exacerbations in the erdosteine group and 74 in the placebo group, with 42.1% and 57.8% of patients, respectively, experiencing an exacerbation. There was a 47% reduction in the mean exacerbation rate with erdosteine compared to placebo (0.27 vs 0.51 exacerbations per-patient per-year, respectively, P=0.003), and a 58.3% reduction in the mild exacerbation rate (0.23 vs 0.53 mild exacerbations per-patient per-year, P=0.001). Mean duration of exacerbations was 26% shorter in erdosteine-treated patients (9.1 vs 12.3 days for placebo, P=0.022), with significant reductions in the duration of mild and moderate-to-severe exacerbations. Mean time to first exacerbation was prolonged by 7.7% (182 days for erdosteine vs 169 days for placebo, P<0.001) and the mean exacerbation-free time was increased by 51 days (279 days for erdosteine vs 228 days for placebo; P<0.001). Conclusion: These results indicate that adding erdosteine to usual COPD maintenance therapy reduces the number of mild, and duration of all, exacerbations in patients with moderate COPD and a history of exacerbations

Enhanced B-cell differentiation and reduced proliferative capacity in chronic hepatitis C and chronic hepatitis B virus infections

BACKGROUND & AIMS: Chronic microial infections aare frequently associated with B-cell activation and polyclonal proliferation, potentially leading to autoimmunity and lymphoproliferative disorders. We assessed B-cell phenotype and function in chronic hepatitis B (HBV) and chronic hepatitis C (HCV) virus infection. METHODS: We studied 70 patients with chronic HCV infection, 34 with chronic HBV infection and 54 healthy controls, B-cell phenotype was assessed by flow cytometry using monoclonal antibodies specific for CD27, the CD69, CD71, and CD86 activation markers and the chemokine receptor CXCR3. Differentiation into immunoglobulin-producing cells (IPC) was analysed by ELISpot upon stimulation and with CD40 ligand+IL-10 as surrogate bystander T-cell help or CpG oligodeoxynucleotide+IL-2, as innate immunity signal. Proliferation was examined by cytometry using carboxyfluorescein diacetate succinimidyl ester (CFSE) after stimulation with CpG. RESULTS: A significantly higher proportion of B cells from both HCV-and HBV-infected patients expressed activation markers compared with controls and a positive correlation was found between CXCR3(+) B cells and HCV RNA values. Memory B cells from patients with chronic HCV and HBV infections showed enhanced differentiation into IPC compared with controls, although this was restricted to IgG and at a lower level in HCV-compared with HBV-infected patients. Moreover, patients' activated B cells displayed significantly lower proliferative ability compared to healthy donors despite low expression of the FcRL4 exhaustin marker. CONCLUSIONS: B-cell activation, but not exhaustion, is common in chronic viral hepatitis. However, enhanced B-cell differentiation and deficient proliferative capacity were not associated with commitment to terminal differentiation