Características do leite de búfalas da raça Mediterrâneo e mestiças Murrah-Mediterrâneo.

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Extensive Investigations on Radial Crack Formation in Labyrinth Seals of Aircraft Engines

Labyrinth seals are due to their non-contact function and their thermal resistance the state of the art in sealing technology for thermal turbomachinery such as jet engines. The purpose of labyrinth seals is to adjust or minimize the leakage between rotor and stator. However, because of transient flight manoeuvres and the resulting mechanical and thermal loads on the components, contact between rotating and stationary parts cannot be ruled out. The aim of this study is to extend the basic understanding of the mechanisms of hot crack formation in the components of a labyrinth seal during the rubbing process. Previous investigations at the Institute of Thermal Turbomachinery have shown that the thermally induced stress caused in connection with the thermal change of the material properties can lead to formation of the cracks in the seal fin. In order to get a deeper understanding of the complex crack initiation mechanisms, it is necessary to carry out fundamental experiments on simplified geometries. For this purpose, the stress conditions of a loaded labyrinth seal are applied to a cylindrical test specimen. It is fixed on both sides and subjected to thermo-cyclic load. To model a rubbing process of a labyrinth seal, the initial temperature of the cycle corresponds to the operating temperature of the rotor in a jet engine and the final temperature corresponds to the contact temperature during the rubbing process. The temperature change causes stress in the specimen due to the rigid mounting. In literature there are analytical considerations regarding the stress-strain curve in the seal fin and a possible pre-damage of the components by remaining tensile stress after the rubbing process. In this paper, these analytical approaches are compared with the test data. Also a residual tensile strength of the seal fin which is still to be tolerated is worked out depending on the temperature load. The stress reduction during heating is very significant and is considered in detail. Due to the high mechanical and thermal loads, the stress reduction is superimposed by relaxation and plastic deformation. For a separate consideration of these basic effects, FE simulations are carried out. The main findings are that stress and strain in the component depends on both the initial and the final temperature of the specimen. The final rubbing temperature mainly influences the remaining tensile stress. With the thus calculated remaining strength of the seal fin a probable crack formation could be determined. The evaluation of this data contributes significantly to the understanding of hot crack formation in labyrinth seal fins and is therefore the basis for the optimization of the sealing system with regard to robustness against rubbing processes

Produção e composição química de cultivares de capim elefante no município de Altamira-PA.

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Perioperative mortality and major cardio-pulmonary complications after lung surgery for non-small cell carcinoma

Objectives: A database of patients operated of lung cancer was analyzed to evaluate the predictive risk factors of operative deaths and life-threatening cardiopulmonary complications. Methods: From 1990 to 1997, data were collected concerning 634 consecutive patients undergoing lung resection for non-small cell carcinoma in an academic medical centre and a regional hospital. Operations were managed by a team of experienced surgeons, anaesthesiologists and chest physicians. Operative mortality was defined as death within 30 days of operation and/or intra-hospital death. Respiratory failure, myocardial infarct, heart failure, pulmonary embolism and stroke were considered as major non-fatal complications. Preoperative risk factors, extent of surgery, pTNM staging, perioperative mortality and major cardiopulmonary complications were recorded and evaluated using chi-square statistics and multivariate logistic regression. Results: Complete data were obtained in 621 cases. The overall operative mortality was 3.2% (n=19). Cardiovascular complications (n=10), haemorrhage (n=4) and sepsis or acute lung injury (n=5) were incriminated as the main causative factors. In addition, there were 13 life-threatening complications (2.1%) consisting in strokes (n=4), myocardial infarcts (n=5), pulmonary embolisms (n=1), acute lung injury (n=1) and respiratory failure (n=2). Four independent predictors of operative death were identified: pneumonectomy, evidence of coronary artery disease (CAD), ASA class 3 or 4 and period 1990-93. In addition, the risk of major complications was increased in hypertensive patients and in those belonging to ASA class 3 or 4. A trend towards improved outcome was observed during the second period, from 1994 to 97. Conclusion: Our data demonstrate that perioperative mortality is mainly dependent on the extent of surgery, the presence of CAD and provision of adequate medical and nursing care. Preoperative testing and interventions to reduce the cardiovascular risk factors may help to further improve perioperative outcom

Extrato hidrossolúvel de soja (leite de soja) com sabores de frutas da Amazônia.

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Light triggered detection of aminophenyl phosphate with a quantum dot based enzyme electrode

An electrochemical sensor for p-aminophenyl phosphate (pAPP) is reported. It is based on the electrochemical conversion of 4-aminophenol (4AP) at a quantum dot (QD) modified electrode under illumination. Without illumination no electron transfer and thus no oxidation of 4AP can occur. pAPP as substrate is converted by the enzyme alkaline phosphatase (ALP) to generate 4AP as a product. The QDs are coupled via 1,4-benzenedithiol (BDT) linkage to the surface of a gold electrode and thus allow potential-controlled photocurrent generation. The photocurrent is modified by the enzyme reaction providing access to the substrate detection. In order to develop a photobioelectrochemical sensor the enzyme is immobilized on top of the photo-switchable layer of the QDs. Immobilization of ALP is required for the potential possibility of spatially resolved measurements. Geometries with immobilized ALP are compared versus having the ALP in solution. Data indicate that functional immobilization with layer-by-layer assembly is possible. Enzymatic activity of ALP and thus the photocurrent can be described by Michaelis- Menten kinetics. pAPP is detected as proof of principle investigation within the range of 25 μM - 1 mM

The antimalarial drug amodiaquine stabilizes p53 through ribosome biogenesis stress, independently of its autophagy-inhibitory activity

Pharmacological inhibition of ribosome biogenesis is a promising avenue for cancer therapy. Herein, we report a novel activity of the FDA-approved antimalarial drug amodiaquine which inhibits rRNA transcription, a rate-limiting step for ribosome biogenesis, in a dose-dependent manner. Amodiaquine triggers degradation of the catalytic subunit of RNA polymerase I (Pol I), with ensuing RPL5/RPL11-dependent stabilization of p53. Pol I shutdown occurs in the absence of DNA damage and without the subsequent ATM-dependent inhibition of rRNA transcription. RNAseq analysis revealed mechanistic similarities of amodiaquine with BMH-21, the first-in-class Pol I inhibitor, and with chloroquine, the antimalarial analog of amodiaquine, with well-established autophagy-inhibitory activity. Interestingly, autophagy inhibition caused by amodiaquine is not involved in the inhibition of rRNA transcription, suggesting two independent anticancer mechanisms. In vitro, amodiaquine is more efficient than chloroquine in restraining the proliferation of human cell lines derived from colorectal carcinomas, a cancer type with predicted susceptibility to ribosome biogenesis stress. Taken together, our data reveal an unsuspected activity of a drug approved and used in the clinics for over 30 years, and provide rationale for repurposing amodiaquine in cancer therapy

Iogurte de leite de búfala com sabores de frutas da Amazônia.

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Adapting Decision DAGs for Multipartite Ranking

European Conference, ECML PKDD 2010, Barcelona, Spain, September 20-24, 2010Multipartite ranking is a special kind of ranking for problems in which classes exhibit an order. Many applications require its use, for instance, granting loans in a bank, reviewing papers in a conference or just grading exercises in an education environment. Several methods have been proposed for this purpose. The simplest ones resort to regression schemes with a pre- and post-process of the classes, what makes them barely useful. Other alternatives make use of class order information or they perform a pairwise classi cation together with an aggregation function. In this paper we present and discuss two methods based on building a Decision Directed Acyclic Graph (DDAG). Their performance is evaluated over a set of ordinal benchmark data sets according to the C-Index measure. Both yield competitive results with regard to stateof- the-art methods, specially the one based on a probabilistic approach, called PR-DDA