996 resultados para pre-flocculation


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Kirjallisuusosassa perehdyttiin retentioaineisiin ja täyteaineisiin sekä retentioaineiden ja rainanmuodostusolosuhteiden vaikutukseen retentioon, vedenpoistoon ja paperin ominaisuuksiin. Tarkemmin kirjallisuusosassa keskityttiin täyteaineiden esiflokkaukseen, retentiopolymeerin adsorptioon sekä retentiopolymeerien ja täyteaineiden annostelutapoihin. Kokeellisessa osassa tutkittiin sarjaa retentiopolymeerejä, joiden varaustiheys ja moolimassa muuttuivat. Yksi polymeereistä oli kahdesta polymeeristävalmistettu suoladispersio ja yksi modifioitu kationinen PAM. Näillä polymeereillä käytiin läpi koesarjoja, joissa muutettiin täyteaineen annosteluaikaa retentiopolymeerin annosteluajan pysyessä vakiona. Lähinnä vertailtiin keskenään perinteistä annostelua, jossa täyteaine annosteltiin paljon ennen retentiopolymeeriä,ja yhtäaikaista annostelua, jossa molemmat annosteltiin yhtä aikaa lähellä perälaatikkoa. Kokeet tehtiin MBF-laitteella, jolla pystytään paperikonetta vastaaviin pulsaatiotaajuuksiin ja sillä voidaan valmistaa tasoviirakoneella valmistetunpaperin kaltaisia laboratorioarkkeja. Valmistetuista arkeista tutkittiin retentioita ja paperiteknisiä ominaisuuksia. Laboratoriokokeiden perusteella yhtäaikainen annostelu antoi paremmat täyteaineretentiot verrattaessa perinteiseen annosteluun lähes kaikissa koesarjoissa. Varsinkin lyhytketjuiset polymeerit näyttivättoimivan hyvin yhtäaikaisannostelulla, mikä saattaisi johtua siitä, että lyhyt reagointiaika sulpun kanssa on lyhytketjuisille polymeereille edullinen, sillä silloin polymeeriketjun konformaatio ei ehdi asettua liian alhaiseksi ja ketjun toimintakyky säilyy parempana. Polymeerin varaustiheyden kasvaessa riittävästi laski täyteaineretentio seuraavissa tapauksissa: SC-massa + kaoliini ja SC-massa +GCC kummallakin annostelulla sekä SC-massa + PCC A perinteisellä annostelulla. Hienopaperimassalla samaa trendiä noudatti täyteaine GCC kummallakin annostelulla, kun taas PCC H:ta käytettäessä paranivat täyteaineretentiot molemmilla annosteluilla. Retentiopolymeerin moolimassan kasvaessa riittävästi kääntyi täyteaineretentio laskuun täyteaineilla GCC ja kaoliini, kun käytettiin SC-massaa. Hienopaperimassalla GCC noudatti tätä samaa taipumusta. Sen sijaan SC-massalla PCC A:takäytettäessä täyteaineretentio puolestaan nousi hieman moolimassan kasvaessa. Näin kävi myös hienopaperimassalla, kun täyteaineena käytettiin PCC H:ta. Käytettäessä SC-massaa, perinteisellä annostelulla saatiin parempi tai yhtä hyvä valonsironta kuin yhtäaikaisella annostelulla kaikilla täyteaineilla. Tämä saattaisi johtua siitä, että yhtäaikaisannostelulla on muodostunut suurempia täyteaineflokkeja, mikä on alentanut valoa sirottavia pintoja. Täyteaineista korkeimmat valonsirontakertoimet antoi PCC A ja alhaisimmat kaoliini. PCC A:lla oli kapein partikkelikokojakauma, mikä korottaa paperin valonsirontaa. Hienopaperimassalla valonsirontakerroin ja opasiteetti suurenivat GCC-pitoisuuden kasvaessa kummallakin annostelulla, mikä voisi johtua täyteainepartikkelien antamasta paremmasta sironnasta. Yhtäaikaisella annostelulla saavutettiin huomattavasti paremmat valonsironnan arvot perinteiseen annosteluun verrattuna. PCC H-pitoisuuden kasvaessa suurenivat myös valonsirontakerroin ja opasiteetti kummallakin annostelulla. PCC H antoi korkeammat valonsirontakertoimet kuin GCC. PCC omaa suuremman valonheijastusluvun kuin GCC, minkä vuoksi se antaa paremmat valonsirontakertoimen arvot. PCC H:n partikkelikokojakauma oli myös kapeampi kuin GCC:n, mikä mahdollisti paremman valonsironnan ja opasiteetin saavuttamisen.

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To identify risk factors associated with post-operative temporomandibular joint dysfunction after craniotomy. The study sample included 24 patients, mean age of 37.3 ± 10 years; eligible for surgery for refractory epilepsy, evaluated according to RDC/TMD before and after surgery. The primary predictor was the time after the surgery. The primary outcome variable was maximal mouth opening. Other outcome variables were: disc displacement, bruxism, TMJ sound, TMJ pain, and pain associated to mandibular movements. Data analyses were performed using bivariate and multiple regression methods. The maximal mouth opening was significantly reduced after surgery in all patients (p = 0.03). In the multiple regression model, time of evaluation and pre-operative bruxism were significantly (p < .05) associated with an increased risk for TMD post-surgery. A significant correlation between surgery follow-up time and maximal opening mouth was found. Pre-operative bruxism was associated with increased risk for temporomandibular joint dysfunction after craniotomy.

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To analyze the relationship between parity, pre-pregnancy body mass index (BMI), and gestational weight gain (GWG). This observational controlled study was conducted from November 2013 to April 2014, with postpartum women who started antenatal care up to 14 weeks and had full-term births. Data were collected from medical records and antenatal cards. Descriptive and bivariate analyses were performed. The significance level was 5%. Data were collected from 130 primiparous and 160 multiparous women. At the beginning of prenatal care, 54.62% of the primiparous were eutrophic, while the majority of multiparous were overweight or obese (62.51%). Multiparas are two times more likely to be obese at the beginning of their pregnancies, when compared to primiparas. The average pre-pregnancy weight and final pregnancy weight was significantly higher in multiparous, however, the mean GWG was higher among primiparous. We found an inverse correlation between parity and the total GWG, but initial BMI was significantly higher in multiparas. Nevertheless, monitoring of the GWG through actions that promote a healthier lifestyle is needed, regardless of parity and nutritional status, in order to prevent excessive GWG and postpartum weight retention and consequently inadequate pre-pregnancy nutritional status in future pregnancies.

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Universidade Estadual de Campinas . Faculdade de Educação Física

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Universidade Estadual de Campinas. Faculdade de Educação Física

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Universidade Estadual de Campinas . Faculdade de Educação Física

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Universidade Estadual de Campinas . Faculdade de Educação Física

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Universidade Estadual de Campinas. Faculdade de Educação Física

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Universidade Estadual de Campinas . Faculdade de Educação Física

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Due to the imprecise nature of biological experiments, biological data is often characterized by the presence of redundant and noisy data. This may be due to errors that occurred during data collection, such as contaminations in laboratorial samples. It is the case of gene expression data, where the equipments and tools currently used frequently produce noisy biological data. Machine Learning algorithms have been successfully used in gene expression data analysis. Although many Machine Learning algorithms can deal with noise, detecting and removing noisy instances from the training data set can help the induction of the target hypothesis. This paper evaluates the use of distance-based pre-processing techniques for noise detection in gene expression data classification problems. This evaluation analyzes the effectiveness of the techniques investigated in removing noisy data, measured by the accuracy obtained by different Machine Learning classifiers over the pre-processed data.

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In this work, the development and evaluation of a hyphenated flow injection-capillary electrophoresis system with on-line pre-concentration is described. Preliminary tests were performed to investigate the influence of flow rates over the analytical signals. Results revealed losses in terms of sensitivity of the FIA-CE system when compared to the conventional CE system. To overcome signal decrease and to make the system more efficient, a lower flow rate was set and an anionic resin column was added to the flow manifold in order to pre-concentrate the analyte. The pre-concentration FIA-CE system presented a sensitivity improvement of about 660% and there was only a small increase of 8% in total peak dispersion. These results have confirmed the great potential of the proposed system for many analytical tasks especially for low concentration samples.

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Estuarine hydrodynamics is a key factor in the definition of the filtering capacity of an estuary and results from the interaction of the processes that control the inlet morphodynamics and those that are acting in the mixing of the water in the estuary. The hydrodynamics and suspended sediment transport in the Camboriú estuary were assessed by two field campaigns conducted in 1998 that covered both neap and spring tide conditions. The period measured represents the estuarine hydrodynamics and sediment transport prior to the construction of the jetty in 2003 and provides important background information for the Camboriú estuary. Each field campaign covered two complete tidal cycles with hourly measurements of currents, salinity, suspended sediment concentration and water level. Results show that the Camboriú estuary is partially mixed with the vertical structure varying as a function of the tidal range and tidal phase. The dynamic estuarine structure can be balanced between the stabilizing effects generated by the vertical density gradient, which produces buoyancy and stratification flows, and the turbulent effects generated by the vertical velocity gradient that generates vertical mixing. The main sediment source for the water column are the bottom sediments, periodically resuspended by the tidal currents. The advective salt and suspended sediment transport was different between neap and spring tides, being more complex at spring tide. The river discharge term was important under both tidal conditions. The tidal correlation term was also important, being dominant in the suspended sediment transport during the spring tide. The gravitational circulation and Stokes drift played a secondary role in the estuarine transport processes.

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O preá do semiárido nordestino (Galea spixii Wagler, 1831) é um roedor pertencente à família Caviidae. Pouca literatura é encontrada sobre essa espécie em relação a sua morfologia e seu comportamento ambiental e reprodutivo. Com o objetivo de entender a morfologia geral, em foco, na inervação do membro pélvico dessa espécie, neste trabalho, foi explorado o nervo isquiático, o qual é o maior de todos os nervos do organismo. Foram utilizados 10 preás (cinco machos e cinco fêmeas) que vieram a óbito por causas naturais, oriundos do Centro de Multiplicação de Animais Silvestres da Universidade Federal Rural do Semiárido (CEMAS/UFERSA). Os animais foram fixados após o óbito em solução aquosa de formaldeído 10% e, após 48 horas de imersão nessa solução, foram dissecados para exposição do nervo isquiático. Dessa forma, os dados obtidos foram compilados em tabelas e expressos em desenhos esquemáticos e fotografias. Os pares de nervos isquiáticos originaram-se de raízes ventrais de L6L7S1 (70%) e de L7S1S2 (30%) e distribuíram-se pelos músculos glúteo profundo, bíceps femural, semitendinoso e semimembranoso.

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Background: Ezetimibe specifically blocks the absorption of dietary and biliary cholesterol and plant sterols. Synergism of ezetimibe-statin therapy on LDL-cholesterol has been demonstrated, but data concerning the pleiotropic effects of this combination are controversial. Objective: This open-label trial evaluated whether the combination of simvastatin and ezetimibe also results in a synergistic effect that reduces the pro-inflammatory status of pre-diabetic subjects. Methods: Fifty pre-diabetic subjects were randomly assigned to one of 2 groups, one receiving ezetimibe (10 mg/day), the other, simvastatin (20 mg/d) for 12 weeks, followed by an additional 12-week period of combined therapy. Blood samples were collected at baseline, 12 and 24 weeks. RESULTS: Total cholesterol, LDL-cholesterol and apolipoprotein B levels decreased in all the periods analyzed (p < 0.01), but triglycerides declined significantly only after combined therapy. Both drugs induced reductions in C-reactive protein, reaching statistical significance after combining ezetimibe with the simvastatin therapy (baseline 0.59 +/- 0.14, simvastatin monotherapy 0.48 +/- 0.12 mg/dL and 0.35 +/- 0.12 mg/dL, p < 0.023). Such a reduction was independent of LDL-cholesterol change. However, mean levels of TNF-alpha and interleukin-6 and leukocyte count did not vary during the whole study. Conclusion: Expected synergistic lowering effects of a simvastatin and ezetimibe combination on LDL-cholesterol, apolipoprotein B and triglycerides levels were confirmed in subjects with early disturbances of glucose metabolism. We suggest an additive effect of this combination also on inflammatory status based on the reduction of C-reactive protein. Attenuation of pro-inflammatory conditions may be relevant in reducing cardiometabolic risk.

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Background: We evaluated growth and nutritional status of preschool children between 2 and 6 years old from low income families from 14 daycare centers. Methods: Cross-sectional study with 1544 children from daycare centers of Santo Andre, Brazil. Body weight (W), height (H) and body mass index (BMI) were classified according to the 2000 National Center for Health Statistics (CDC/NCHS). Cutoff points for nutritional disorders: -2 z scores and 2.5 and 10 percentiles for malnutrition risk, 85 to 95 percentile for overweight and above BMI 95 percentile for obesity. Stepwise Forward Regression method was used including age, gender, birth weight, breastfeeding duration, age of mother at birth and period of time they attended the daycare center. Results: Children presented mean z scores of H, W and BMI above the median of the CDC/NCHS reference. Girls were taller and heavier than boys, while we observed similar BMI between both genders. The z scores tended to rise with age. A Pearson Coefficient of Correlation of 0.89 for W, 0.93 for H and 0.95 for BMI was documented indicating positive association of age with weight, height and BMI. The frequency of children below -2 z scores was lower than expected: 1.5% for W, 1.75% for H and 0% for BMI, which suggests that there were no malnourished children. The other extremity of the distribution evidenced prevalence of overweight and obesity of 16.8% and 10.8%, respectively. Conclusion: Low income preschool children are in an advanced stage of nutritional transition with a high prevalence of overweight.