Numerical Simulation of Rain Scavenging on Large Release of Water-Soluble Gases

A depth-integrated numerical model GP_Rain was developed to calculate the behavior of neutrally buoyant, highly soluble gases subjected to scavenging by rain. A neutrally buoyant release of hydrogen fluoride is used to illustrate the use of the model. The GP_Rain model was developed in two steps. The part without rain scavenging is based on AFTOX, a Gaussian puff/plume model. Then a first-order decay term for rain scavenging, which was developed by assuming a homogeneous rain field, was added to the concentration calculation for the puff. The model can predict the maximum release distance for a certain concentration limitation and a two-dimensional plume with or without rain.     

Mutant K-ras oncogenes in colon cancers Do not predict Patient's chemotherapy response or survival

One half of human colon cancers bear mutant c-K-ras oncogenes. Mutant K-ras oncogenes are associated with shortened survival in non-small cell lung cancers, and, in cell line models, with resistance to cis-platinum and to ionizing radiation. This study examines whether mutant K-ras alleles in colon cancer alter patients' response to chemotherapy or survival. We studied 37 patients who received chemotherapy with 5-fluorouracil and leucovorin, Exon 1 of the c-K-ras gene was PCR amplified from DNA extracted from paraffin-embedded tumor blocks. The presence of mutant or wild-type c-K-ras alleles was determined by dideoxy sequencing of the PCR-amplified c-K-ras DNA. c-K-ras mutations at codons 12 or 13 were present in 19 and absent in 18 cases. Responses to chemotherapy were equally likely in patients with either wild-type or mutant c-K-ras, occurring in 28% of patients with wild-type ras and 32% of patients with mutant ras (P = 0.8). Survival was also indistinguishable among both groups. Median survival from diagnosis was 35 months for ras wild-type patients and 31 months for ras mutant patients (P = 0.96). Median survival from starting chemotherapy was 14 months for ras wild-type patients and 17 months for ras mutant patients (P = 0.26). Patients with colon cancers bearing either wild-type or mutant c-K-ras alleles are indistinguishable in overall survival and are equally likely to respond to 5-fluorouracil-based chemotherapy.     

Prolonged bradyarrhythmias after coronary revascularization surgery

The authors report four cases of prolonged bradyarrhythmias after isolated coronary artery bypass graft surgery. All the four patients required permanent pacemaker implantation. Etiologic factors of conduction disturbances after coronary artery bypass and long term follow-up are discussed.     

Joint source coding and data rate adaptation for energy efficient wireless video streaming

Rapid growth in wireless networks is fueling demand for video services from mobile users. While the problem of transmitting video over unreliable channels has received some attention, the wireless network environment poses challenges such as transmission power management that have received little attention previously in connection with video. Transmission power management affects battery life in mobile devices, interference to other users, and network capacity. We consider energy efficient transmission of a video sequence under delay and quality constraints. The selection of source coding parameters is considered jointly with transmitter power and rate adaptation, and packet transmission scheduling. The goal is to transmit a video frame using the minimal required transmission energy under delay and quality constraints. Experimental results are presented that illustrate the advantages of the proposed approach.     

Evaluation of Diluted and Undiluted Trickle-Bed Hydrotreating Reactor with Different Catalyst Volume

In this work, a comparative study on the combined effects of hydrodynamics and kinetics on the hydrodesulfurization (HDS) of a straight-run gas oil (SRGO) using a trickle-bed reactor with and without diluent (SiC) and different catalyst volume (0.1, 0.07, and 0.050 × 10^-3 m³, respectively) was carried out. The tests were conducted in a pilot plant under conditions close to those used in industrial-scale units (5492 kPa, 445.4 m³(STP)/m³ H₂/oil ratio, 623-643K, 0.9 and 2.5 h^-1 LHSV values). The catalyst used was a commercial CoMoP/Al₂O₃ formulation shaped as tri-lobed extrudates (1/20 in, nominal size) or as crushed particles (d_p = 1.2 × 10^-3 m). Contrarily to that usually claimed, the undiluted systems showed better performance than those comprising small diluent (SiC) particles (d_p ~ 5 × 10^-5 m). Calculations to evaluate hydrodynamic variables (plug-flow behavior, wall effects, wetting, and back-mixing) were carried out in order to explain the observed facts. The possible influences of the size of the diluent particles used are discussed.     

Residual effect of atomised water vapour treatment on carbohydrate metabolism during ripening of cv “Fino de Jete” cherimoya fruit

Atomised hot water vapour at between 46 and 54 °C for 60 min was tested as a method of delaying ripening and extending shelf life in cv “Fino de Jete” cherimoya fruit (Annona cherimola Mill.). Heat treatment at 46 °C stimulated the respiration rate and starch degradation, induced ethylene production, increased the accumulation of soluble sugars and α-amylase activity, and moved the onset of ethylene production (OEP) forward. Treatment at 50 °C, and especially at 52 °C, delayed the climacteric peak and the OEP, decreased sugar and organic acid accumulation, and reduced α-amylase and invertase activity. The results obtained indicate that temperatures higher than 48 °C slowed physiological processes and carbohydrate metabolism and extend the shelf life of the cherimoya fruits, while temperatures higher than 52 °C blocked ripening irreversibly.     

Characterisation of 39 varietal virgin olive oils by their volatile compositions

Thirty-nine single virgin olive oils from eight producer countries, but cultivated in the same orchard under identical agronomic and pedoclimatic conditions, were characterised by 64 volatile compounds quantified by dynamic headspace-gas chromatography. The method was validated by analysing the relative standard deviation in repeatability and intermediate reproducibility of each volatile compound. Data on the total content of volatiles and C6 compounds – responsible for the green odour perception-, and the total content of hydrocarbons, aldehydes, alcohols, ketones and esters are displayed and discussed for each individual virgin olive oil. Fifty volatile compounds were characterised by their sensory attributes, determined by olfactometry. The Student t-test was used to determine the level of significance of each volatile compound characterising the varieties. The odour threshold and the maximum concentration of the most notable volatiles are also displayed. Finally, the Brown-Forsythe test and stepwise linear discriminant analysis were used to check the ability of the volatiles to cluster the varietal virgin olive oils according to their autochthonous geographical origin.     

Late p53 mutation in head and neck oncogenesis

p53 mutation are currently recognized as the commonest genetic event in human tumors. In this paper are studied, through immunochemistry, the p53 protein expression of 25 carriers from squamous cell carcinoma of the larynx and hypopharynx as well in the non tumoral mucosa of the larynx removed and corresponding metastases. Because of the great overexpression of this protein among tumors and its metastases, aside with the low expression in normal far-off mucous membranes of the studied growths, the AA. draw out the conclusion that p53 mutation is a late event by neck and head oncogenesis.