Efeito antagônico do ferro e do zinco em uma formulação de alimentação enteral utilizando planejamento de misturas da metodologia de superfície de resposta

Nutritional therapy with enteral diets became substantially specialized over the last years. This work's aim was to study the effect of the components of a formulation: fiber, calcium and medium-chain triglycerides for dialysability of minerals. Analysis of multiple variables was carried out using response surface methodology. The level curve showed an antagonic effect of interaction between iron and zinc. TCM was the variable responsible for characterizing competition between the two minerals in the formulation. More studies on foods are needed for knowing the effecs of minerals in formulations.

Numerical Investigation of Flow Past a Circular Cylinder and in a Staggered Tube Bundle Using Various Turbulence Models

Transitional flow past a three-dimensional circular cylinder is a widely studied phenomenon since this problem is of interest with respect to many technical applications. In the present work, the numerical simulation of flow past a circular cylinder, performed by using a commercial CFD code (ANSYS Fluent 12.1) with large eddy simulation (LES) and RANS (κ - ε and Shear-Stress Transport (SST) κ - ω! model) approaches. The turbulent flow for ReD = 1000 & 3900 is simulated to investigate the force coefficient, Strouhal number, flow separation angle, pressure distribution on cylinder and the complex three dimensional vortex shedding of the cylinder wake region. The numerical results extracted from these simulations have good agreement with the experimental data (Zdravkovich, 1997). Moreover, grid refinement and time-step influence have been examined. Numerical calculations of turbulent cross-flow in a staggered tube bundle continues to attract interest due to its importance in the engineering application as well as the fact that this complex flow represents a challenging problem for CFD. In the present work a time dependent simulation using κ – ε, κ - ω! and SST models are performed in two dimensional for a subcritical flow through a staggered tube bundle. The predicted turbulence statistics (mean and r.m.s velocities) have good agreement with the experimental data (S. Balabani, 1996). Turbulent quantities such as turbulent kinetic energy and dissipation rate are predicted using RANS models and compared with each other. The sensitivity of grid and time-step size have been analyzed. Model constants sensitivity study have been carried out by adopting κ – ε model. It has been observed that model constants are very sensitive to turbulence statistics and turbulent quantities.

In vitro effect of substrate, temperature and photoperiod on Phakopsora pachyrhizi urediniospore germination and germ tube growth

In vitro experiments were conducted to assess the effects of substrate, temperature and time of exposure to temperature and photoperiod on P. pachyrhizi uredospore germination and germ tube growth. The following substrates were tested: water-agar and soybean leaf extract-agar at different leaf concentrations (0.5, 1.0, 2.0 and 4.0 g of leaves and 15g agar/L water), temperatures (10, 15, 20, 25, 30, and 35oC) and times of exposure (1, 2, 3, 4, 5, 6, 7, and 8 hours) to temperature and 12 different photoperiods. The highest germination and germ tube length was found for the soybean leaf extract agar. Maximum P. pachyrhizi uredospore germination was obtained at 21.8 and 22.3°C, and maximum germ tube growth at 21.4 and 22.1°C. The maximum uredospore germination was found at 6.4 hours exposure, while the maximum germ tube length was obtained at 7.7 h exposure. Regarding photoperiod, the maximum spore germination and the maximum uredospore germ tube length were found in the dark. Neither spore germination nor uredospore germ tube growth was completely inhibited by the exposure to continuous light.

Corrosion behaviour of boiler tube materials during combustion of fuels containing Zn and Pb

Många förbränningsanläggningar som bränner utmanande bränslen såsom restfraktioner och avfall råkar ut för problem med ökad korrosion på överhettare och/eller vattenväggar pga. komponenter i bränslena som är korrosiva. För att minimera problemen i avfallseldade pannor hålls ångparametrarna på en relativt låg nivå, vilket drastiskt minskar energiproduktionen. Beläggningarna i avfallseldade pannor består till största delen av element som är förknippade med högtemperaturkorrosion: Cl, S, alkalimetaller, främst K och Na, och tungmetaller som Pb och Zn, och det finns också indikationer av Br-förekomst. Det låga ångtrycket i avfallseldade pannor påverkar också stålrörens temperatur i pannväggarna i eldstaden. I dagens läge hålls temperaturen normalt vid 300-400 °C. Alkalikloridorsakad (KCl, NaCl) högtemperaturkorrosion har inte rapporterats vara relevant vid såpass låga temperaturer, men närvaro av Zn- och Pb-komponenter i beläggningarna har påvisats förorsaka ökad korrosion redan vid 300-400 °C. Vid förbränning kan Zn och Pb reagera med S och Cl och bilda klorider och sulfater i rökgaserna. Dessa tungmetallföreningar är speciellt problematiska pga. de bildar lågsmältande saltblandningar. Dessa lågsmältande gasformiga eller fasta föreningar följer rökgasen och kan sedan fastna eller kondensera på kallare ytor på pannväggar eller överhettare för att sedan bilda aggressiva beläggningar. Tungmetallrika (Pb, Zn) klorider och sulfater ökar risken för korrosion, och effekten förstärks ytterligare vid närvaro av smälta. Motivet med den här studien var att få en bättre insikt i högtemperaturkorrosion förorsakad av Zn och Pb, samt att undersöka och prediktera beteendet och motståndskraften hos några stålkvaliteter som används i överhettare och pannväggar i tungmetallrika förhållanden och höga materialtemperaturer. Omfattande laboratorie-, småskale- och fullskaletest utfördes. Resultaten kan direkt utnyttjas i praktiska applikationer, t.ex. vid materialval, eller vid utveckling av korrosionsmotverkande verktyg för att hitta initierande faktorer och förstå deras effekt på högtemperaturkorrosion.

Nova técnica de alimentação enteral em fístulas esôfago-jejunais

BACKGROUND: A new procedure for the treatment of esophageal fistula, mainly associated to the ebb esophagojejunal in patients submitted to the total gastrectomy and reconstruction with loop jejunal Rouxen-Y anastomosis is present. METHODS: The method is based in the use of "probe standard enteral prolongated with drain to laminate adapted in extremity", which results in advanced positioning inside the jejunum, making the administration of enteral nutrition possible and impeding ebb esophagojejunal. RESULTS: The authors discuss the theoretical advantages of the procedure and they suggest that the treatment of esofagic fistula with probe prolonged enteral would be suitable in the treatment of the fistula esophagojejunal by preventing the ebb esophagojejunal, which would result in smaller period of duration of the fistula esophagojejunal and it would prevent the high mortality rate. CONCLUSIONS: Preliminary studies demonstrated that this is a technically easy, low cost procedure through the endoscopic use. A prospective evaluation for morbility and mortality related to the method is needed.

The impact of a chest tube management protocol on the outcome of trauma patients with tube thoracostomy

ABSTRACTObjective:to investigate the effect of standardized interventions in the management of tube thoracostomy patients and to assess the independent effect of each intervention.Methods:A chest tube management protocol was assessed in a retrospective cohort study. The tube thoracostomy protocol (TTP) was implemented in August 2012, and consisted of: antimicrobial prophylaxis, chest tube insertion in the operating room (OR), admission post chest tube thoracostomy (CTT) in a hospital floor separate from the emergency department (ED), and daily respiratory therapy (RT) sessions post-CTT. The inclusion criteria were, hemodynamic stability, patients between the ages of 15 and 59 years, and injury severity score (ISS) < 17. All patients had isolated injuries to the chest wall, lung, and pleura. During the study period 92 patients were managed according to the standardized protocol. The outcomes of those patients were compared to 99 patients treated before the TTP. Multivariate logistic regression analysis was performed to assess the independent effect of each variable of the protocol on selected outcomes.Results:Demographics, injury severity, and trauma mechanisms were similar among the groups. As expected, protocol compliance increased after the implementation of the TTP. There was a significant reduction (p<0.05) in the incidence of retained hemothoraces, empyemas, pneumonias, surgical site infections, post-procedural complications, hospital length of stay, and number of chest tube days. Respiratory therapy was independently linked to significant reduction (p<0.05) in the incidence of seven out of eight undesired outcomes after CTT. Antimicrobial prophylaxis was linked to a significant decrease (p<0.05) in retained hemothoraces, despite no significant (p<0.10) reductions in empyema and surgical site infections. Conversely, OR chest tube insertion was associated with significant (p<0.05) reduction of both complications, and also significantly decreased the incidence of pneumonias.Conclusion:Implementation of a TTP effectively reduced complications after CTT in trauma patients.

Teaching project: a low-cost swine model for chest tube insertion training

Objective: to describe and evaluate the acceptance of a low-cost chest tube insertion porcine model in a medical education project in the southwest of Paraná, Brazil. Methods: we developed a low-cost and low technology porcine model for teaching chest tube insertion and used it in a teaching project. Medical trainees - students and residents - received theoretical instructions about the procedure and performed thoracic drainage in this porcine model. After performing the procedure, the participants filled a feedback questionnaire about the proposed experimental model. This study presents the model and analyzes the questionnaire responses. Results: seventy-nine medical trainees used and evaluated the model. The anatomical correlation between the porcine model and human anatomy was considered high and averaged 8.1±1.0 among trainees. All study participants approved the low-cost porcine model for chest tube insertion. Conclusion: the presented low-cost porcine model for chest tube insertion training was feasible and had good acceptability among trainees. This model has potential use as a teaching tool in medical education.

Pressure drop coefficients for elliptic and circular sections in one, two and three-row arrangements of plate fin and tube heat exchangers

The objective of the present work is the experimental determination of pressure drop coefficients (loss coefficients) for elliptic and circular sections in one, two and three-row arrangements of plate fin and tube heat exchangers. The experiments permitted to correlate the dimensionless loss coefficient with the flow Reynolds number in the rectangular channel formed by the plate fins. The experimental technique consisted of the measurement of the longitudinal pressure distribution along the flow channel, for several values of air mass flow rate. The total number of data runs, each one characterized by the flow Reynolds number, was 216. The present geometry is used in compact heat exchangers for air conditioning systems, heaters, radiators, and others. Also, it is verified the influence of the utilization of elliptic tubes, instead of circular ones, in the pressure drop. The measurements were performed for Reynolds numbers ranging from 200 to 1900.

The effect of shielding gas feeding method in laser welding of steel

Gas shielding plays an important role in laser welding phenomena. This is because it does not only provide shielding against oxidization but it has an effect in beam absorption and thus welds penetration. The goal of this thesis is to study and compare the effects of different shielding gas feeding methods in laser welding of steel. Research method is a literature survey. It is found that the inclination angle and the arrangement of the gas feeding nozzles affect the phenomena significantly. It is suggested that by designing shielding gas feeding case specifically better welding results can be obtained.

Atrial natriuretic peptide and feeding activity patterns in rats

This review presents historical data about atrial natriuretic peptide (ANP) from its discovery as an atrial natriuretic factor (ANF) to its role as an atrial natriuretic hormone (ANH). As a hormone, ANP can interact with the hypothalamic-pituitary-adrenal axis (HPA-A) and is related to feeding activity patterns in the rat. Food restriction proved to be an interesting model to investigate this relationship. The role of ANP must be understood within a context of peripheral and central interactions involving different peptides and pathways