999 resultados para waste variability


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The main purpose of this study was to investigate the level of agreement between the gas exchange threshold (GET) and heart rate variability threshold (HRVT) during maximal cardiopulmonary exercise testing (CPET) using three different exercise modalities. A further aim was to establish whether there was a 1:1 relationship between the percentage heart rate reserve (%HRR) and percentage oxygen uptake reserve (%V˙O2R) at intensities corresponding to GET and HRVT. Sixteen apparently healthy men 17 to 28 years of age performed three maximal CPETs (cycling, walking, and running). Mean heart rate and V˙O2 at GET and HRVT were 16 bpm (P<0.001) and 5.2 mL·kg-1·min-1 (P=0.001) higher in running than cycling, but no significant differences were observed between running and walking, or cycling and walking (P>0.05). There was a strong relationship between GET and HRVT, with R2 ranging from 0.69 to 0.90. A 1:1 relationship between %HRR and %V˙O2R was not observed at GET and HRVT. The %HRR was higher during cycling (GET mean difference=7%; HRVT mean difference=11%; both P<0.001), walking (GET mean difference=13%; HRVT mean difference=13%; both P<0.001), or running (GET mean difference=11%; HRVT mean difference=10%; both P<0.001). Therefore, using HRVT to prescribe aerobic exercise intensity appears to be valid. However, to assume a 1:1 relationship between %HRR and %V˙O2R at HRVT would probably result in overestimation of the energy expenditure during the bout of exercise.

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The autonomic nervous system maintains homeostasis, which is the state of balance in the body. That balance can be determined simply and noninvasively by evaluating heart rate variability (HRV). However, independently of autonomic control of the heart, HRV can be influenced by other factors, such as respiratory parameters. Little is known about the relationship between HRV and spirometric indices. In this study, our objective was to determine whether HRV correlates with spirometric indices in adults without cardiopulmonary disease, considering the main confounders (e.g., smoking and physical inactivity). In a sample of 119 asymptomatic adults (age 20-80 years), we evaluated forced vital capacity (FVC) and forced expiratory volume in 1 s (FEV1). We evaluated resting HRV indices within a 5-min window in the middle of a 10-min recording period, thereafter analyzing time and frequency domains. To evaluate daily physical activity, we instructed participants to use a triaxial accelerometer for 7 days. Physical inactivity was defined as <150 min/week of moderate to intense physical activity. We found that FVC and FEV1, respectively, correlated significantly with the following aspects of the RR interval: standard deviation of the RR intervals (r =0.31 and 0.35), low-frequency component (r =0.38 and 0.40), and Poincaré plot SD2 (r =0.34 and 0.36). Multivariate regression analysis, adjusted for age, sex, smoking, physical inactivity, and cardiovascular risk, identified the SD2 and dyslipidemia as independent predictors of FVC and FEV1 (R2=0.125 and 0.180, respectively, for both). We conclude that pulmonary function is influenced by autonomic control of cardiovascular function, independently of the main confounders.

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En av naturens mest grundläggande aspekter är den enorma mängd av variation som existerar mellan arter. Denna variation har lett oss till att klassificera olika organismer på basis av morfologiska skillnader och på senare tid till att jämföra genetiska skillnader på individens nivå. Den marina kiselalgen Skeletonema marinoi är en av de vanligaste växtplanktonarter i Östersjön under vårblomningen och anses viktig för den årliga produktionen. En av mina främsta målsättningar var att beskriva den intra-specifika diversiteten hos denna art längs med miljögradienter i Östersjön. Ett annat mål var att klargöra de faktorer som eventuellt är involverade i konfigurationen av genetisk diversitet och differentiering. Med hjälp av genetiska markörer visade jag att den genetiska diversiteten hos S. marinoi populationer i Östersjön är lägre jämfört med populationer i östra delen av Nordsjön. Arten är genetiskt uppdelad så att en utpräglad population förekommer i Östersjön och en annan, genetiskt åtskild population förekommer norr om de Danska sunden. Resultaten visar att de genetiskt åtskilda populationerna är anpassade till lokala salinitetsförhållanden. Genflödet mellan populationerna korrelerade kraftigt med havströmmar i området. Mina studier avslöjade även omfattande variation av fenotypiska, ekologiskt vikitga särdrag hos olika kloner. Djurplankton som äter kiselalger kunde modifiera den klonala mångfalden av fenotypiskt variabla S. marinoi populationer. En ökad klonal mångfald ledde till högre prestationsförmåga i fråga om primär produktion och stabiliserade ekofysiologiska funktioner. Som visas i denna avhandling består en art allt som oftast av åtskilliga genetiska varianter med fenotypiska skillnader. Kunskap om sådana intra-specifika skillnader är en förutsättning för att vi skall kunna förstå var och varför arter förekommer. Denna kunskap utgör även en grund för prognoser som siktar på att förutspå huruvida arter kan anpassa sig till framtida miljöförhållanden. ------------------------------------------------------ Suunnaton määrä variaatioita eliölajien välillä on perustavanlaatuinen ominaisuus luonnossa. Perinteisesti tätä monimuotoisuutta on käytetty organismien luokittelemiseen eri lajeihin niiden morfologisten eroavaisuuksien perusteella. Hiljattain myös geneettisten erojen huomioimista yksilötasolla on hyödynnetty lajien luokittelemisessa. Merialueilla esiintyvä piilevä, Skeletonema marinoi on yksi Itämeren tavallisimmista kasviplanktonlajeista kevätkukinnan aikana. Tavoitteenani oli selventää geneettistä ja fenotyyppistä monimuotoisuutta pitkin Itämeren ympäristögradienttejä. Geneettisen monimuotoisuuteen ja erkaantumiseen vaikuttavien tekijöiden selvittäminen oli tärkeä aspekti väitöstutkimuksessani. Geneettisiä markkereita käyttämällä pystyin toteamaan, että S. marinoi levän geneettinen monimuotoisuus on Itämeressä merkittävästi alhaisempi kuin läheisessä Pohjanmeren itäosassa. Tutkittu laji jakautuu geneettisesti yhteen erilliseen populaatioon Itämeressä ja toiseen selvästi erottuvaan populaatioon Tanskan salmien pohjoispuolella. Kokeellisten tulosten perusteella nämä geneettisesti erilaistuneet populaatiot ovat kumpikin sopeutuneet paikalliseen veden suolapitoisuuteen. Populaatioiden välisen geenivirran ja merivirtojen luoman yhteyden välillä havaittiin vahva korrelaatio. Tutkimukseni paljastivat myös laajaa vaihtelua Skeletonema-kloonien ekologisesti tärkeissä ominaisuuksissa. Kokeellisten tutkimusteni perusteella laiduntajat pystyivät muuttamaan geneettisten kloonien lukumäärää monimuotoisissa S. marinoi populaatioissa. Lisääntynyt kloonien lukumäärä paransi perustuotantokykyä ja vakautti ekofysiologisia toimintoja. Kuten tässä väitöstutkimuksessa osoitetaan, lajit koostuvat useimmiten lukuisista geneettisistä muunnelmista, jotka eroavat usein fenotyypeiltään. Ymmärtääksemme missä tietyt lajit esiintyvät ja miksi, tarvitsemme tietoa lajien sisäisistä vaihteluista. Tämä tieto on tarpeellista, jotta voimme ennustaa lajien sopeutumista tuleviin ympäristönmuutoksiin.

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This study is done to examine waste power plant’s optimal processing chain and it is important to consider from several points of view on why one option is better than the other. This is to insure that the right decision is made. Incineration of waste has devel-oped to be one decent option for waste disposal. There are several legislation matters and technical options to consider when starting up a waste power plant. From the tech-niques pretreatment, burner and flue gas cleaning are the biggest ones to consider. The treatment of incineration residues is important since it can be very harmful for the envi-ronment. The actual energy production from waste is not highly efficient and there are several harmful compounds emitted. Recycling of waste before incineration is not very typical and there are not many recycling options for materials that cannot be easily re-cycled to same product. Life cycle assessment is a good option for studying the envi-ronmental effect of the system. It has four phases that are part of the iterative study process. In this study the case environment is a waste power plant. The modeling of the plant is done with GaBi 6 software and the scope is from gate-to-grave. There are three different scenarios, from which the first and second are compared to each other to reach conclusions. Zero scenario is part of the study to demonstrate situation without the power plant. The power plant in this study is recycling some materials in scenario one and in scenario two even more materials and utilize the bottom ash more ways than one. The model has the substitutive processes for the materials when they are not recycled in the plant. The global warming potential results show that scenario one is the best option. The variable costs that have been considered tell the same result. The conclusion is that the waste power plant should not recycle more and utilize bottom ash in a number of ways. The area is not ready for that kind of utilization and production from recycled materials.

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Alfa Laval Aalborg Oy designs and manufactures waste heat recovery systems utilizing extended surfaces. The waste heat recovery boiler considered in this thesis is a water-tube boiler where exhaust gas is used as the convective heat transfer medium and water or steam flowing inside the tubes is subject to cross-flow. This thesis aims to contribute to the design of waste heat recovery boiler unit by developing a numerical model of the H-type finned tube bundle currently used by Alfa Laval Aalborg Oy to evaluate the gas-side heat transfer performance. The main objective is to identify weaknesses and potential areas of development in the current H-type finned tube design. In addition, numerical simulations for a total of 15 cases with varying geometric parameters are conducted to investigate the heat transfer and pressure drop performance dependent on H-type fin geometry. The investigated geometric parameters include fin width and height, fin spacing, and fin thickness. Comparison between single and double tube type configuration is also conducted. Based on the simulation results, the local heat transfer and flow behaviour of the H-type finned tube is presented including boundary layer development between the fins, the formation of recirculation zone behind the tubes, and the local variations of flow velocity and temperature within the tube bundle and on the fin surface. Moreover, an evaluation of the effects of various fin parameters on heat transfer and pressure drop performance of H-type finned tube bundle has been provided. It was concluded that from the studied parameters fin spacing and fin width had the most significant effect on tube bundle performance and the effect of fin thickness was the least important. Furthermore, the results suggested that the heat transfer performance would increase due to enhanced turbulence if the current double tube configuration is replaced with single tube configuration, but further investigation and experimental measurements are required in order to validate the results.

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This study was carried out to evaluate the antioxidant capacity of the agro-industrial waste from acerola. Hydroacetone, hydroethanolic, and hydromethanolic extracts were obtained using the sequential extraction process, and they were screened for their free radical DPPH• (1,1-diphenyl-2-picrilhidrazil) and ABTS•+ (2,2'-azino-bis-(3-etilbenzotiazolin 6-sulfonic acid) scavenging activity and their effect on the linoleic acid peroxidation by the ferric thiocyanate method. Soybean oil with the addition of the extracts (200 ppm) was submitted to Schaal oven test (60 °C, 28 days), in which the samples were analyzed for peroxide value and conjugated dienes. Hydroethanolic and hydromethanolic extracts exhibited good DPPH scavenging activity (low value of EC50 and TEC50 and high value of AE), good ABTS scavenging capacity (1445.1 and 1145.5 µMol TEAC.g-1, respectively), and high percentage inhibition of peroxidation of linoleic acid (96.12 and 91.84%, respectively) and showed the ability to retard the formation of peroxides and conjugated dienes.

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The aim of this work was to perform the microbiological and physicochemical characterization of surimi made from waste of piramutaba filleting. The results of physicochemical characterization of the waste and surimi were: moisture (76.37 and 79.11%), total lipids (5.35 and 0.74%), proteins (14.92 and 10.79%), ash (3.03 and 2.35%), pH (6.9 and 7.4), caloric value (109.15 and 77.86 kcal.g-1), and water activity (both 0.98), respectively. The results of the levels of total volatile bases were 7.29 mgN/100-1 g (waste) and 7.01% carbohydrate (surimi). The values of total lipids and proteins were reduced during the preparation of surimi, probably due to successive washes during the processing. Waste and surimi were examined microbiologically and are in compliance with required parameters. The results show a loss of red (a* parameter) and yellow (b* parameter) color. On the other hand, the L* parameter (lightness) increased after the processing of surimi. It can be concluded that piramutaba waste can be used for surimi preparation and as a source of nutrients for human consumption, providing an alternative use of these wastes avoiding their disposal polluting the environment.

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There is a trend towards the use of novel technologies nowadays, mainly focused on biological processes, for recycling and the efficient utilization of organic residues that can be metabolized by different microorganisms as a source of energy. In the present study the isolation of bacterial strains from six different agro-industrial by-products and waste was performed with the objective of evaluating their hydrolytic capacities and suitability for use in bioconversion of specific substrates. The 34 isolated strains were screened in specific culture media for the production of various hydrolytic enzymes (lipase, protease, cellulase, and amylase). It was found that 28 strains exhibited proteolytic activity, 18 had lipolytic activity, 13 had caseinolytic activity, 15 had amylolytic activity, and 11 strains exhibited cellulolytic activity. The strains that showed the highest hydrolytic capacities with biotechnological potential were selected, characterized genotipically, and identified as Bacillus, Serratia, Enterococcus, Klebsiella, Stenotrophomonas, Lactococcus, and Escherichia genera. It was concluded that the strain isolates have a high potential for use in the bioconversion of agro-industrial waste, both as a pure culture and as a microbial consortium.

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Acerola is a fruit that can be consumed in the form of juice and pulp. However, during its processing, a large amount of waste is generated (seed and bagasse). Adding value to these by-products is of great interest, since their use can enrich foods with nutrients and fiber. In this study, we performed phytochemical screening, determined the proximate and mineral composition, bioactive compounds and the technological functional properties of acerola seed flour and acerola bagasse flour. Seeds were dried in a ventilated oven at ± 45 °C and the bagasse was lyophilized. Samples were ground, stored in flasks protected from light. Phytochemical screening revealed metabolites of nutritional and pharmacological interest and no potentially toxic substances in the flours. Seed flour and bagasse flour showed high levels (g 100 g- 1 of dry matter - DM) of soluble fiber: 4.76 and 8.74; insoluble fiber: 75.76 and 28.58, and phenolic compounds: 4.73 and 10.82, respectively. The flours also showed high absorption of water, oil and emulsion stability, presenting potential for inclusion in meat products and bakery products.

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Potato pulp waste (PPW) drying was investigated under different experimental conditions (temperatures from 50 to 70 °C and air flow from 0.06 to 0.092 m³ m- 2 s- 1) as a possible way to recover the waste generated by potato chip industries and to select the best-fit model to the experimental results of PPW drying. As a criterion to evaluate the fitting of mathematical models, a method based on the sum of the scores assigned to the four evaluated statistical parameters was used: regression coefficient (R²), relative mean error P (%), root mean square error (RMSE), and reduced chi-square (χ²). The results revealed that temperature and air velocity are important parameters to reduce PPW drying time. The models Midilli and Diffusion had the lowest sum values, i.e., with the best fit to the drying data, satisfactorily representing the drying kinetics of PPW.

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The fish industry generates high volume of waste from fish oil that can have the extraction of its lipids used as nutraceuticals and foods. The objective of this study was to produce unsaturated fatty acids from industrialized fish oil by means of a differentiated hydrolysis process. The samples used were crude fish oil obtained from Campestre industry and characterized through physical-chemical parameters, according to AOCS: acidity, peroxide, saponification, iodine and percentage of free fatty acids and also obtained the fatty acid profile through derivatization method for gas chromatography. The results obtained for the oleochemical indices for refined oil were similar to the data found on the literature. The content of polyunsaturated fatty acids (PUFA) was found of 32,78%, with 9,12% of docosahexaenoic (DHA) and 10,36% of eicosapentaenoic (EPA), regarding monounsaturated fatty acids (MUFA) content was of 30,59% in the hydrolyzed fish oil in relation to refined (20,06%). Thus, it can be concluded that the hydrolysis process used for oils from fish-waste was satisfactory on the production of absolute yield of lipids in the process and significant preservation on the percentages of EPA and DHA, interesting on the production of nutraceuticals and nutrition of aquatic animals, including shrimp in captivity.

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AbstractThe objective of this study was to evaluate the genetic variability for synthesis of bioactive compounds in pepper (Capsicum annuum, Solanaceae). Total phenolics, anthocyanins, carotenoids and antioxidant activity were evaluated in 14 accessions of Capsicum annuum from the Capsicum Genebank of Embrapa Temperate Agriculture (Pelotas – RS, Brazil). Thirty plants of each accession were cultivated in the field during spring and summer. The experimental design was a complete randomized block with 14 treatments (accessions) and three replications. The laboratory evaluations followed the same experimental design to field, but with two repetitions more. Seeds were discarded and opposite longitudinal portions of fruits were manually prepared for chemical analyzes. The data obtained showed high genetic variability for phenolics, anthocyanins, carotenoids and antioxidant activity. The P39, P77, P119, P143 and P302 accessions exhibited the highest levels of antioxidants, which are strongly indicated to be used in breeding programs of Capsicum peppers.

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Abstract Biodegradable films blends made of safflower oil nutraceutical capsules waste corn starch (20:4, 30:4, 40:4 and 50:4) were prepared. The objective of this study was to evaluate the influence of addition of different concentrations of safflower oil nutraceutical capsule waste in the mechanical properties (tensile strength, elongation at break, Young’s modulus) and thickness of corn starch films. A decrease in tensile strength and Young’s modulus and an increase in elongation at break were observed with the increase in the content of the nutraceutical capsule waste. The results showed that the blends of safflower oil capsules waste-corn starch films demonstrated promising characteristics to form biodegradable films with different mechanical characteristics.

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The correlation of soil fertility x seed physiological potential is very important in the area of seed technology but results published with that theme are contradictory. For this reason, this study to evaluate the correlations between soil chemical properties and physiological potential of soybean seeds. On georeferenced points, both soil and seeds were sampled for analysis of soil fertility and seed physiological potential. Data were assessed by the following analyses: descriptive statistics; Pearson's linear correlation; and geostatistics. The adjusted parameters of the semivariograms were used to produce maps of spatial distribution for each variable. Organic matter content, Mn and Cu showed significant effects on seed germination. Most variables studied presented moderate to high spatial dependence. Germination and accelerated aging of seeds, and P, Ca, Mg, Mn, Cu and Zn showed a better fit to spherical semivariogram: organic matter, pH and K had a better fit to Gaussian model; and V% and Fe showed a better fit to the linear model. The values for range of spatial dependence varied from 89.9 m for P until 651.4 m for Fe. These values should be considered when new samples are collected for assessing soil fertility in this production area.