989 resultados para mechanical parameters of rock mass


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The effects of the addition to sausage mix of tocopherols (200 mg/kg), a conventional starter culture with or without Staphylococcus carnosus, celery concentrate (CP) (0.23% and 0.46%), and two doses of nitrate (70 and 140 mg/kg expressed as NaNO(3)) on residual nitrate and nitrite amounts, instrumental CIE Lab color, tocol content, oxidative stability, and overall acceptability were studied in fermented dry-cured sausages after ripening and after storage. Nitrate doses were provided by nitrate-rich CP or a chemical grade source. The lower dose complies with the EU requirements governing the maximum for ingoing amounts in organic meat products. Tocopherol addition protected against oxidation, whereas the nitrate dose, nitrate source, or starter culture had little influence on secondary oxidation values. The residual nitrate and nitrite amounts found in the sausages with the lower nitrate dose were within EU-permitted limits for organic meat products and residual nitrate can be further reduced by the presence of the S. carnosus culture. Color measurements were not affected by the CP dose. Product consumer acceptability was not affected negatively by any of the factors studied. As the two nitrate sources behaved similarly for the parameters studied, CP is a useful alternative to chemical ingredients for organic dry-cured sausage production.

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The warp of corrugated board is the most prevalent quality problem incorrugated board industry. Nowadays corrugators provide high quality board but there often occurs a warp problem within the production of some board grades. One of the main reasons for that are the humidity and the temperature levels of the raw materials. The goal of the research is to find out howthe adjusted corrugator recipe parameters required for appropriate running of the corrugated board are repeatable for the considered board grades, how the temperature and humidity imbalances of the raw material papers influence on the warpformation of the finished board. Furthermore, the solutions for preventing warpof corrugated board are presented in the thesis.

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Diplomityön tavoitteena on tutkia mitä uusia tiedonhallinnallisia ongelmia ilmenee, kun massaräätälöidyn tuotteen tuotetieto hallitaan läpi tuotteen elinkaaren, sekä miten nämä ongelmat voitaisiin ratkaista. Ongelmat ja haasteet kerätään kirjallisuuslähteistä ja massaräätälöintiprosessi yhdistetään PLM-vaiheisiin. Ratkaisua tutkitaan testaamalla kuinka standardit STEP ja PLCS sekä standardeja tukeva PLM järjestelmä voisivat tukea massaräätälöidyn tuotteen elinkaaren tiedonhallintaa. MC tuotteiden ongelmia ovat tuoterakenteen monimutkaisuus, jäljitettävyys ja muutosten hallinta läpi elinkaaren. STEP ja PLCS pystyvät kummatkin tahollaan tukemaan tiedonhallintaa. MC-tuotteen geneerinen tuoterakenne on kuitenkin manuaalisesti liittettävä elinkaaritiedon tukemiseen. PLM-järjestelmä pystyy tukemaan MC-tuotteiden elinkaarta, mutta koska toiminto ei ole järjestelmään sisäänrakennettuna, MC-tuotteiden tukemisen parantamisessa on edelleen haasteita.

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Objective: to assess the diagnostic accuracy of different anthropometric markers in defining low aerobic fitness among adolescents. Methods: cross-sectional study on 2,331 boys and 2,366 girls aged 10 - 18 years. Body mass index (BMI) was measured using standardized methods; body fat (BF) was assessed by bioelectrical impedance. Low aerobic fitness was assessed by the 20-meter shuttle run using the FITNESSGRAMR criteria. Waist was measured in a subsample of 1,933 boys and 1,897 girls. Overweight, obesity and excess fat were defined according to the International Obesity Task Force (IOTF) or FITNESSGRAMR criteria. Results: 38.5% of boys and 46.5% of girls were considered as unfit according to the FITNESSGRAMR criteria. In boys, the area under the ROC curve (AUC) and 95% confidence interval were 66.7 (64.1 - 69.3), 67.1 (64.5 - 69.6) and 64.6 (61.9 - 67.2) for BMI, BF and waist, respectively (P<0.02). In girls, the values were 68.3 (65.9 - 70.8), 63.8 (61.3 - 66.3) and 65.9 (63.4 - 68.4), respectively (P<0.001). In boys, the sensitivity and specificity to diagnose low fitness were 13% and 99% for obesity (IOTF); 38% and 86% for overweight + obesity (IOTF); 28% and 94% for obesity (FITNESSGRAMR) and 42% and 81% for excess fat (FITNESSGRAMR). For girls, the values were 9% and 99% for obesity (IOTF); 33% and 82% for overweight + obesity (IOTF); 22% and 94% for obesity (FITNESSGRAMR) and 26% and 90% for excess fat (FITNESSGRAMR). Conclusions: BMI, not body fat or waist, should be used to define low aerobic fitness. The IOTF BMI cut-points to define obesity have a very low screening capacity and should not be used.

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The aim of this study was to identity metabolites and transformation products (TPs) in chicken muscle from amoxicillin (AMX), cephapirin (PIR) and ceftiofur (TIO), which are antibiotics of the β-lactam family. Liquid chromatography coupled to quadrupole time-of-flight (QqTOF) mass spectrometry was utilized due to its high resolution, high mass accuracy and MS/MS capacity for elemental composition determination and structural elucidation. Amoxicilloic acid (AMA) and amoxicillin diketopiperazine (DKP) were found as transformation products from AMX. Desacetylcephapirin (DAC) was detected as a metabolite of PIR. Desfuroylceftiofur (DFC) and its conjugated compound with cysteine (DFC-S-Cys) were detected as a result of TIO in contact with chicken muscle tissue. The metabolites and transformation products were also monitored during the in vivo AMX treatment and slaughtering period. It was found that two days were enough to eliminate AMX and associated metabolites/transformation products after the end of administration.

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Parkinson disease (PD) is associated with a clinical course of variable duration, severity, and a combination of motor and non-motor features. Recent PD research has focused primarily on etiology rather than clinical progression and long-term outcomes. For the PD patient, caregivers, and clinicians, information on expected clinical progression and long-term outcomes is of great importance. Today, it remains largely unknown what factors influence long-term clinical progression and outcomes in PD; recent data indicate that the factors that increase the risk to develop PD differ, at least partly, from those that accelerate clinical progression and lead to worse outcomes. Prospective studies will be required to identify factors that influence progression and outcome. We suggest that data for such studies is collected during routine office visits in order to guarantee high external validity of such research. We report here the results of a consensus meeting of international movement disorder experts from the Genetic Epidemiology of Parkinson's Disease (GEO-PD) consortium, who convened to define which long-term outcomes are of interest to patients, caregivers and clinicians, and what is presently known about environmental or genetic factors influencing clinical progression or long-term outcomes in PD. We propose a panel of rating scales that collects a significant amount of phenotypic information, can be performed in the routine office visit and allows international standardization. Research into the progression and long-term outcomes of PD aims at providing individual prognostic information early, adapting treatment choices, and taking specific measures to provide care optimized to the individual patient's needs.

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To improve our understanding of the limiting factors during repeated sprinting, we manipulated hypoxia severity during an initial set and examined the effects on performance and associated neuro-mechanical alterations during a subsequent set performed in normoxia. On separate days, 13 active males performed eight 5-s sprints (recovery = 25 s) on an instrumented treadmill in either normoxia near sea-level (SL; FiO2 = 20.9%), moderate (MH; FiO2 = 16.8%) or severe normobaric hypoxia (SH; FiO2 = 13.3%) followed, 6 min later, by four 5-s sprints (recovery = 25 s) in normoxia. Throughout the first set, along with distance covered [larger sprint decrement score in SH (-8.2%) compared to SL (-5.3%) and MH (-7.2%); P < 0.05], changes in contact time, step frequency and root mean square activity (surface electromyography) of the quadriceps (Rectus femoris muscle) in SH exceeded those in SL and MH (P < 0.05). During first sprint of the subsequent normoxic set, the distance covered (99.6, 96.4, and 98.3% of sprint 1 in SL, MH, and SH, respectively), the main kinetic (mean vertical, horizontal, and resultant forces) and kinematic (contact time and step frequency) variables as well as surface electromyogram of quadriceps and plantar flexor muscles were fully recovered, with no significant difference between conditions. Despite differing hypoxic severity levels during sprints 1-8, performance and neuro-mechanical patterns did not differ during the four sprints of the second set performed in normoxia. In summary, under the circumstances of this study (participant background, exercise-to-rest ratio, hypoxia exposure), sprint mechanical performance and neural alterations were largely influenced by the hypoxia severity in an initial set of repeated sprints. However, hypoxia had no residual effect during a subsequent set performed in normoxia. Hence, the recovery of performance and associated neuro-mechanical alterations was complete after resting for 6 min near sea level, with a similar fatigue pattern across conditions during subsequent repeated sprints in normoxia.

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Satellite transmitters and geographic-positioning-system devices often add substantial mass to birds to which they are attached. Studies on the effects of such instruments have focused on indirect measures, whereas the direct influence of extra mass on pelagic behavior is poorly known. We used 2.5-g geolocators to investigate the effect of extra mass on the pelagic behavior of Cory's Shearwaters (Calonectris diomedea) by comparing the traits of a single foraging trip among a group carrying 30-g weights, a group carrying 60-g weights, and a control group. The weights were attached to the birds' backs using typical techniques for attaching satellite transmitters to seabirds. The extra mass increased the duration of the birds' trips and decreased their foraging efficiency and mass gained at sea. These indirect effects may be related to foraging traits: weighted birds showed a greater search effort than control birds, traveled greater distances, covered a greater foraging area, and increased the maximum foraging range. Furthermore, the time spent on the sea surface at night was greater for weighted than for control groups, which showed that the extra mass also affected activity patterns. Our results underline the need to quantify the effects of monitoring equipment commonly used to study the pelagic behavior of seabirds. We suggest that geolocators can be used to obtain control data on foraging-trip movements and activity patterns.

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The general task of clamping devise is to connect the parts to the machining centers so that the work piece could be fixed on its position during the whole machining process. Additionally, the work piece should be clamped easily and rapidly by the machine users. The purpose of this Master’s thesis project was to develop a product design and find out the dimensioning of a hydraulic vise system for Astex Engineering OY, which was taking care of the general principles of product design and development during the design process. Throughout the process, the needs of manufacturing and assembling were taken into consideration for the machinability and minimization of the cost of manufacturing. The most critical component of the clamping devise was modeled by FEM for the issue of strength requirements. This 3D model was created with Solidworks and FEM-analysis was done with Cosmos software. As the result of this design work, a prototype of the hydraulic vise was manufactured for Astex Engineering OY and the practical test.

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Worldwide cultivation of corn is expanding, due in part to the increasing production of bioethanol. In consequence, huge amounts of corn stalks residues are been produced. Instead of incineration, we transformed the corn stalks into a semichemical pulp and successfully applied it as reinforcement in polypropylene composites. PP composites reinforced with 40% wt corn stalk single fibers were prepared, and their mechanical properties were evaluated. Through mechanical properties modeling of the composites, the intrinsic tensile strength of the cellulosic fibers that constitute the corn stalk have been determined

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Lignin was used as a natural adhesive to manufacture Vitis vinifera fiberboards. The fiberboards were produced at laboratory scale by adding powdered lignin to material that had previously been steam-exploded under optimized pretreatment and pressing conditions. The kraft lignin used was washed several times with an acidic solution to eliminate any contaminants and low molecular weight compounds. This research studied the effects of amounts of lignin ranging from 5% to 20% on the properties of Vitis vinifera fiberboards. The fiberboard properties evaluated were density, water resistance in terms of thickness swelling, water absorption, and the mechanical properties in terms of modulus of rupture, modulus of elasticity, and internal bond. Results showed that fiberboards made from Vitis vinifera without lignin addition had weaker mechanical properties. However, the fiberboards obtained using acid-washed kraft lignin as a natural adhesive had good mechanical and water resistance properties that fully satisfied the relevant standard specifications

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Stingless bees produce a honey that is different from the Apis honey in terms of composition. There aren't enough data to establish quality control parameters for this product, mainly due to lack of research results. The aim of this work is to evaluate some physicochemical parameters that can be used for the characterization and for the quality control of the Meliponinae honey. Four different samples were collected in the Amazon region of Brazil in 2004 (Melipona compressipes manaoense bee and Melipona seminigra merribae bee). Honey analyses were performed as described by the official methods. The mean results were: moisture (30.13%), pH (3.65), acidity (24.57 mEq/kg), water activity (0.75), fructose (31.91%), glucose (29.30%) and sucrose (0.19%). These results reinforce the need for a specific regulation for stingless bee honey. This will only be feasible when enough data is available to establish upper and lower limits for the physicochemical parameters used for quality control.