971 resultados para Tension artérielle


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The increasing demand for water resources accentuates the need to reduce water waste through a more appropriate irrigation management. In the particular case of irrigated coffee planting, which in recent years presented growth with the predominance of drip irrigation, the improvement of drip irrigation management techniques is a necessity. The proper management of drip irrigation depends on the knowledge of the spatial pattern of soil moisture distribution inside the wetted strip formed under the irrigation lines. In this study, grids of 24 tensiometers were used to determine the water storage within the wetted strip formed under drippers, with a 3.78 L h-1 discharge, evenly spaced by 0.4 m, subjected to two different management criteria (fixed irrigation interval and 60 kPa tension). Estimates of storage based on a one-dimensional analysis, that only considers depth variations, were compared with two-dimensional estimates. The results indicate that for high-frequency irrigation the one-dimensional analysis is not appropriate. However, under less frequent irrigation, the two-dimensional analysis is dispensable, being the one-dimensional sufficient for calculating the water volume stored in the wetted strip.

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The air included in droplets generated by spray nozzles directly int0erferes in transport, deposition and retention of the droplets after its impact on the target. The objective of this study was to analyze the interference of adjuvants in the amount of air included in droplets generated by spray nozzles. The treatments were composed by four spray solutions containing mineral oil, vegetable oil, surfactant and water, and three spray nozzles, two air induction type and one pre-orifice. The air included was calculated by the difference between the volume of spray mix (air plus liquid) and only the liquid, which was made by means of sprayed samples captured in a funnel and collected in a graduated cylinder. The surface tension was estimated by the gravimetric method using a precision scale and a graduated pipette. The surfactant provided the largest percentage of air included in the spray. For the surface tension, the mineral oil and the surfactant had the lowest values. It was concluded that the use of adjuvants had a direct influence on the percentage of air included. In addition, products with greater ability to reduce surface tension and to form homogeneous solutions provided the increase in the percentage of air included in the droplet.

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This study defined the main adjuvant characteristics that may influence or help to understand drift formation process in the agricultural spraying. It was evaluated 33 aqueous solutions from combinations of various adjuvants and concentrations. Then, drifting was quantified by means of wind tunnel; and variables such as percentage of droplets smaller than 50 μm (V50), 100 μm (V100), diameter of mean volume (DMV), droplet diameter composing 10% of the sprayed volume (DV0.1), viscosity, density and surface tension. Assays were performed in triplicate, using Teejet XR8003 flat fan nozzles at 200 kPa (medium size droplets). Spray solutions were stained with Brilliant Blue Dye at 0.6% (m/ v). DMV, V100, viscosity cause most influence on drift hazardous. Adjuvant characteristics and respective methods of evaluation have applicability in drift risk by agricultural spray adjuvants.

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The physical characteristics of a spray liquid are important in getting a good droplet formation and control efficiency over a particular target. As a function of these characteristics, it is possible to decipher which is the best adjuvant based on the respective concentration used during the spray. Therefore, ten spraying liquids were prepared, which varied in concentrations of pesticide lufenuron + profenofos, mineral oil, water and manganese sulfate. Pendant droplets formed from these mixtures were measured to examine their impact on surface tension. Droplets were applied to the surface of coffee leaves and the surface tension, contact angle formed and the leaf area wetted by the droplet, were measured. A smooth glass surface was taken as a comparative to the coffee leaves. The highest concentrations of oil resulted in lower surface tension, smaller contact angles of droplets on leaf surfaces and larger areas wetted by the droplets. Both surfaces showed hydrophilic behavior.

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ABSTRACT Proper irrigation management is important both to enable adequate water supply and to minimize problems with diseases, nutrient leaching and unnecessary water and power wastes. Thus, this study aimed at improving irrigation management in greenhouses. For that reason, we assessed the effect of various water tensions on yield performance of crisphead lettuce, Raider-Plus cv. , grown with mulching. The experiment was conducted in greenhouse at the Federal University of Lavras. Treatments constituted five different soil water tensions, namely 12, 25, 35, 45, and 70 kPa. The results showed that irrigation must be carried out at water soil tension of around 12 kPa to reach satisfying commercial values for both total and commercial yield, 66 and 50 t ha-1, as well as keeping good vegetable quality. At this tension, total water consumption was of 167.25 mm. The water use efficiency demonstrated quadratic response to treatments, with high water consumption efficiency found in intermediate treatments (35 and 45 kPa), achieving values of 579.87 and 471.71 kg ha -1mm-1, respectively.

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ABSTRACT Surfactant use in spray solutions has a major advantage of reducing droplet surface tension and increasing deposition. We aimed to evaluate droplet deposition on cattail plants (Typha subulata) using food coloring (Brilliant Blue - FD & C-1) as marker added to spray solution at two different growth stages: vegetative (4 leaves) and flowering (5 leaves). The treatments were arranged in a completely randomized design with four replications and five plants per plot (16.2-L tanks). Treatments consisted of adding into spray solutions Brilliant Blue alone (control), Brilliant Blue + 0.5% v/v Aterbane and Brilliant Blue + 0.01% v/v Silwet. Spraying was performed by a pressurized CO2 sprayer at 220 kPa using two Teejet XR 8002 nozzles at a spray volume of 200 L ha-1. We observed that surfactant addition provided uniform deposition of spray solution on T. subulata plants at both growth stages compared to treatments without surfactant. However, this product has not increased spray deposits on cattail leaves at both stages.

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A rare case of blunt traumatic abdominal hernia is presented in which jejunal loops herniated through the abdominal wall. The patient had a serious motor vehicle accident seven years ago, while wearing the seat belt. He developed a traumatic hernia in the anterior lateral abdominal wall, which was operated, and relapsed after some months. The patient was reoperated and we observed the unattachment of the anterior lateral abdominal musculature from the ilium crest. After the hernial sac treatment, the defect was solved with the use of a polypropylene mesh. The postoperative evolution was good and four months later there were no signs of recurrence. Traumatic abdominal hernia remains a rare clinical entity, despite the increase in blunt abdominal trauma. Traumatic abdominal wall hernia falls into two general categories: small lower quadrant abdominal defects, typically the result of blunt trauma with bicycle handlebars, and larger abdominal wall defects related to motor vehicle accidents. The diagnosis may be often established by the physical examination alone. Conventional radiology and computerized tomography usefulness have been proved. In the vast majority of cases, early repair is recommended. The appropriate treatment is the reduction of the herniated bowel into the abdomen, the debridment of nonviable tissues, and a primary tension free closure of the detect.

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BACKGROUND: Liver vascular isolation is essential for the treatment of the retrohepatic vena cava and hepatic veins. Triple vessel occlusion (TVO - occlusion of the portal triad, the inferior vena cava above the renal veins and within the pericardium) is the easiest isolation method for the surgeon. Unfortunately, this technique cannot be applied to hypovolemic and/or shock (cardiac arrest) patients as it compromises venous return. OBJECTIVES: Our objective is to demonstrate that in the above mentioned patients, establishing a previous hypervolemic state allows the safe use of TVO. METHODS: The method includes efficient injury tamponade with aggressive fluid replacement until normal blood volume is reached (resuscitation). Normal blood volume is recognized by a return of arterial blood pressure to normal levels, inferior vena cava filling and an increase in aortic wall tension. Following this procedure, hypervolemia is obtained by the rapid additional infusion of 1.500 to 2.000 ml of fluids. TVO in this situation does not alter the heart rhythm and maintains a clear operative field which is essential for hepatotomy, venorrhaphy and or venous ligation. RESULTS: Three patients were successfully operated.

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Damage control surgery is one of the major advances in surgical practice in the last 20 years. The indications for damage control surgery are: the need to terminate a laparotomy rapidly in an exsanguinating, hypothermic patient who had developed a coagulopathy and who is about to die on the operating table; inability to control bleeding by direct hemostasis; and inability to close the abdomen without tension because of massive visceral edema and a tense abdominal wall. Damage control surgery has three phases: 1) laparotomy to control hemorrhage by packing, shunting, or balloon tamponade, or both; control of intestinal spillage by resection or ligation of damaged bowel, or both; 2) physiological resuscitation to correct hypothermia, metabolic acidosis, and coagulopathy. 3) planned reoperation for definitive repair. Damage control surgery is appropriate in a small number of critically ill patients who are likely to require substantial hospital resources. However, there are many questions that need to be answered. Who is the patient elected for this surgery? When is the ideal time to make the decision? Which are the parameters that indicate to the surgeons the moment to re-operate the patient? How to treat the long-term complications? In the present review we described some historical aspects, indications, technical aspects, advantages and disadvantages of this procedure, as well as its physiological consequences and morbidity and mortality rates of damage control surgery. Damage control surgery offers a simple effective alternative to the traditional surgical management of complex or multiple injuries in critically injured patients.

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Diplomityön tarkoitus oli selvittää verhopäällystyspastoille sopivia analyysimenetelmiä. Verhopäällystyksessä onnistunut päällystystapahtuma vaatii venymäviskositeetin ja pintajännityksen hyvää hallintaa. Kirjallisuusosassa käsiteltiin verhopäällystystä, verhopäällystyspastojen koostumusta, reologiaa ja pintajännitystä. Kirjallisuusosassa käsiteltiin lisäksi verhopäällystyspastojen reologian ja pintajännityksen mittaamiseen soveltuvia mittausmenetelmiä. Verhopäällystyksen luonteen vuoksi kirjallisuusosassa syvennyttiin venymäviskositeetin ja dynaamisen pintajännityksen mittaamiseen tarkoitettuihin menetelmiin. Kokeellisessa osassa tutkittiin päällystyspastasarjojen reologiaa ja pintajännitystä verhopäällystystä varten. Osaan päällystyspastoista luotiin venymäviskositeettia ja osasta laskettiin pintajännitystä. Venymäviskositeetin mittaamista varten työssä käytettiin ACAV A2 -reometriin liitettyjä teräsreikälevyjä. Dynaamisen pintajännityksen mittaamista varten työssä käytettiin KSV BPA-800P -pintajännitysmittaria. ACAV A2 -reometriin liitettyjen teräsreikälevyjen (reiän sisähalkaisija 0,5 tai 0,7 mm) avulla mitattiin venymäviskositeettia kuvaavia Eulerin lukuarvoja onnistuneesti suurilla kiintoainepitoisuuksilla (50, 60 tai 65 p %). Erikoispaksuntajan määrää lisäämällä onnistuttiin luomaan huomattavaa venymäviskositeettia. Kiintoainepitoisuuden kasvaessa kasvoi myös venymäviskositeetti. Tavanomaisille paksuntajille mitattiin hieman kohonneita venymäviskositeetteja verrattuna referenssipäällystyspastaan. Pigmenttikoostumuksella (kalsiumkarbonaatti/kaoliini) ei näyttänyt olevan vaikutusta venymäviskositeettiin, tai vaikutus oli suhteellisen pieni. Dynaamisen pintajännityksen mittaamista varten käytössä ollut KSV BPA-800P -pintajännitysmittari ei toiminut luotettavasti, vaikka näytteitä laimennettiin. Kiintoainepitoisuudessa 10 p-% olleilla laimennoksilla saavutettiin analysoinnin kannalta parhaat tulokset. Tuloksista saatiin kuitenkin viitteitä, että kyseinen mittari voisi olla potentiaalinen menetelmä dynaamisen pintajännityksen mittaamiseksi.

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Cell division (mitosis) is a fundamental process in the life cycle of a cell. Equal distribution of chromosomes between the daughter cells is essential for the viability and well-being of an organism: loss of fidelity of cell division is a contributing factor in human cancer and also gives rise to miscarriages and genetic birth defects. For maintaining the proper chromosome number, a cell must carefully monitor cell division in order to detect and correct mistakes before they are translated into chromosomal imbalance. For this purpose an evolutionarily conserved mechanism termed the spindle assembly checkpoint (SAC) has evolved. The SAC comprises a complex network of proteins that relay and amplify mitosis-regulating signals created by assemblages called kinetochores (KTs). Importantly, minor defects in SAC signaling can cause loss or gain of individual chromosomes (aneuploidy) which promotes tumorigenesis while complete failure of SAC results in cell death. The latter event has raised interest in discovery of low molecular weight (LMW) compounds targeting the SAC that could be developed into new anti-cancer therapeutics. In this study, we performed a cell-based, phenotypic high-throughput screen (HTS) to identify novel LMW compounds that inhibit SAC function and result in loss of cancer cell viability. Altogether, we screened 65 000 compounds and identified eight that forced the cells prematurely out of mitosis. The flavonoids fisetin and eupatorin, as well as the synthetic compounds termed SACi2 and SACi4, were characterized in more detail utilizing versatile cell-based and biochemical assays. To identify the molecular targets of these SAC-suppressing compounds, we investigated the conditions in which SAC activity became abrogated. Eupatorin, SACi2 and SACi4 preferentially abolished the tensionsensitive arm of the SAC, whereas fisetin lowered also the SAC activity evoked by lack of attachments between microtubules (MTs) and KTs. Consistent with the abrogation of SAC in response to low tension, our data indicate that all four compounds inhibited the activity of Aurora B kinase. This essential mitotic protein is required for correction of erratic MT-KT attachments, normal SAC signaling and execution of cytokinesis. Furthermore, eupatorin, SACi2 and SACi4 also inhibited Aurora A kinase that controls the centrosome maturation and separation and formation of the mitotic spindle apparatus. In line with the established profound mitotic roles of Aurora kinases, these small compounds perturbed SAC function, caused spindle abnormalities, such as multi- and monopolarity and fragmentation of centrosomes, and resulted in polyploidy due to defects in cytokinesis. Moreover, the compounds dramatically reduced viability of cancer cells. Taken together, using a cell-based HTS we were able to identify new LMW compounds targeting the SAC. We demonstrated for the first time a novel function for flavonoids as cellular inhibitors of Aurora kinases. Collectively, our data support the concept that loss of mitotic fidelity due to a non-functional SAC can reduce the viability of cancer cells, a phenomenon that may possess therapeutic value and fuel development of new anti-cancer drugs.