860 resultados para Complexity reduction
Resumo:
Metabolic acidosis has profound effects on vascular tone. This study investigated the in vivo effects of acute metabolic acidosis (AMA) and chronic metabolic acidosis (CMA) on hemodynamic parameters and endothelial function. CMA was induced by ad libitum intake of 1% NH4Cl for 7 days, and AMA was induced by a 3-h infusion of 6 M NH4Cl (1 mL/kg, diluted 1:10). Phenylephrine (Phe) and acetylcholine (Ach) dose-response curves were performed by venous infusion with simultaneous venous and arterial blood pressure monitoring. Plasma nitrite/nitrate (NOx) was measured by chemiluminescence. The CMA group had a blood pH of 7.15±0.03, which was associated with reduced bicarbonate (13.8±0.98 mmol/L) and no change in the partial pressure of arterial carbon dioxide (PaCO2). The AMA group had a pH of 7.20±0.01, which was associated with decreases in bicarbonate (10.8±0.54 mmol/L) and PaCO2 (47.8±2.54 to 23.2±0.74 mmHg) and accompanied by hyperventilation. Phe or ACh infusion did not affect arterial or venous blood pressure in the CMA group. However, the ACh infusion decreased the arterial blood pressure (ΔBP: -28.0±2.35 mm Hg [AMA] to -4.5±2.89 mmHg [control]) in the AMA group. Plasma NOx was normal after CMA but increased after AMA (25.3±0.88 to 31.3±0.54 μM). These results indicate that AMA, but not CMA, potentiated the Ach-induced decrease in blood pressure and led to an increase in plasma NOx, reinforcing the effect of pH imbalance on vascular tone and blood pressure control.
Resumo:
This study proposes alternatives to the current methods of processing round-cooked lobster. The paralyzation of lobsters with direct electric shock consumes 10.526 x 10-3 kWh, which is significantly less than the 11 kWh required by the traditional thermal-shock method (based on 60 kg of lobsters). A better weight gain was obtained by immersion of paralyzed lobsters in brine before cooking. Systematic trials combining 3, 6, or 9% brine concentrations with immersion periods of 15, 30, or 45 minutes were performed in order to determine the best combinations. A mathematical model was designed to predict the weight gain of lobsters of different sizes in any combination of treatments. For small lobsters, a 45 minutes immersion in 6% brine gave the best response in terms of weight gain (4.7%) and cooking produced a weight loss of only 1.34% in relation to fresh lobster weight. For medium-sized lobsters, a 45 minutes immersion in 9% brine produced a weight gain of 2.64%, and cooking a weight gain of 1.08%. For large lobsters, a 45 minutes immersion in 6% brine produced a weight gain of 3.87%, and cooking a weight gain of 1.62%.
Resumo:
In this study, the replacement of 50% NaCl by KCl in Bologna sausage with the addition of herbs and spice blends (coriander, onion, white pepper, cardamom, and Jamaican pepper) was evaluated. The formulations tested showed a significant reduction in the sodium content with no major alterations in the emulsion stability, texture, and microbiological characteristics. The use of 50% KCl caused a reduction in the sensory quality leading to a significant decrease in the consumers' purchase intention. The formulations with the addition of herbs and spice blends presented better results in the sensory evaluation indicating that this strategy can reduce the negative effects resulting from the use of KCl.
Resumo:
The carcass fast freezing is one of the aspects of great prominence to the final quality of pork. In order to reduce weight loss, two experiments were performed, in which the carcasses were monitored during 20 hours to evaluate the main variables involved during two different freezing processes (standard and proposed) as follows: microbiological quality, storage temperature, relative humidity (RH) and air velocity. In experiment I, the carcasses were submitted to a system using heat shock (2 hours in static tunnel at - 25 °C) and subsequently sent to the equalization chamber. In experiment II, the carcasses were submitted to the heat shock and stored in a chamber with RH between 80-85%. The chambers used in both experiments showed no change in the variables studied (internal temperature of 5 °C and air velocity of approximately 0.3 m/s). However, the relative humidity in the three chambers was evaluated and significant differences were found; as a consequence, high levels of weight loss were observed in both chambers In experiment II there was an increase of RH, which reduced the weight loss of the carcasses.
Resumo:
The aim of this study was to evaluate the influence of different concentrations of inulin and pectin as fat substitutes on the chemical composition, texture, and sensory acceptance of frankfurter sausages. Six treatments were evaluated to test fat replacement: control (T0); low fat control (T1); low fat with 15% inulin (T2); low fat with 30% inulin (T3); low fat with 7.5% inulin and 7.5% pectin (T4); and low fat with 15% inulin and 15% pectin (T5). The addition of fibers increased the yield (T3 and T5; 98.96%), and the color parameters were slightly reduced (T3). Moisture (61.14%) and ashes (6.96%) of sausages with inulin and pectin were higher (T5), while shear force, hardness, fracturability, gumminess, and chewiness (T3 and T5) were slightly lower than those of the control. The addition of inulin (T2) increased the sensory acceptance of the sausages (5.75). Fat can be replaced with inulin and pectin in frankfurter sausages to produce healthy and functional products.
Resumo:
Abstract Sodium chloride in meat products provides microbiological stability and desirable technological and sensory effects. Therefore, the reduction of this ingredient is a challenge for the meat industry. The objective of this study was to evaluate the physicochemical and sensory characteristics of ready-to-eat sliced frozen roast beef with partial replacement of sodium chloride by a commercial additive mostly composed of potassium chloride. The analyses performed were chemical composition, cooking yield and post defrosting loss, microbiological evaluation and sensory analysis. There was higher moisture content (p < 0.05) in the control treatment (without the presence of the replacement additive) and all treatments were not different (p ≥ 0.05) in the cooking yield and in post-defrosting loss. The results of microbiological analysis are according to Brazilian Legislation. The sensory evaluation showed no difference between the control treatment and the T1 treatment (with the reduction of 35% of NaCl), while the T2 treatment (with reduction of 70% of NaCl) had the lowest average values in all attributes. The study showed that the reduction of 35% NaCl for commercial additive, mostly composed of potassium chloride, in roast beef is feasible since no changes were observed in sensory and technological characteristics evaluated.
Resumo:
This Master’s Thesis analyses the effectiveness of different hedging models on BRICS (Brazil, Russia, India, China, and South Africa) countries. Hedging performance is examined by comparing two different dynamic hedging models to conventional OLS regression based model. The dynamic hedging models being employed are Constant Conditional Correlation (CCC) GARCH(1,1) and Dynamic Conditional Correlation (DCC) GARCH(1,1) with Student’s t-distribution. In order to capture the period of both Great Moderation and the latest financial crisis, the sample period extends from 2003 to 2014. To determine whether dynamic models outperform the conventional one, the reduction of portfolio variance for in-sample data with contemporaneous hedge ratios is first determined and then the holding period of the portfolios is extended to one and two days. In addition, the accuracy of hedge ratio forecasts is examined on the basis of out-of-sample variance reduction. The results are mixed and suggest that dynamic hedging models may not provide enough benefits to justify harder estimation and daily portfolio adjustment. In this sense, the results are consistent with the existing literature.
Resumo:
Tutkimuksen tavoitteena on kuvata suomalaisen PK-yrityksen kasvamista globaa- liksi toimijaksi. Tapahtunut kasvu on tarkoittanut case-yrityksen kohdalla liike- vaihdon ja henkilöstömäärän kasvun lisäksi myös toimipaikkojen määrän kasvua ja organisaatiorakenteen monimutkaistumista. Näiden muutosten perusteella ja ta- pahtuneiden muutoskohtien avulla on löydettävissä yrityksen toimintaa kuvaavia vaiheita, joita ovat alkuvaihe, kasvuvaihe ja kypsä vaihe. Näiden vaiheiden jälkeen tulee vielä neljäs vaihe, eli uusiutumisvaihe tai laskeva vaihe. Tämän neljännen vaiheen suunta riippuu yrityksen kyvystä uusiutua ja kehittyä vastaamaan uusiin tuleviin haasteisiin joita aikaisempaa globaalimpi toiminta tuo tullessaan. Tapahtuneilla muutoksilla on ollut myös vaikutusta tietohallintoon. Tämä tieto- hallinnossa tapahtunut muutos onkin tämän tutkimuksen ydin, eli mitä haasteita ja vaatimuksia Trafotekin tietohallinto on kohdannut toiminnan eri vaiheissa, ja onko tietohallinto pystynyt omalta osaltaan vastaamaan näihin vaatimuksiin. Toiminnan alkuvaiheessa tietotekniikalla ei ollut suurtakaan strategista ja liike- toimintaa tukevaa roolia, ja tietohallinto pystyikin vastaamaan liiketoiminnan vaa- timuksiin. Tässä vaiheessa Trafotekissa ei ollut erillistä tietohallintoa, vaan tieto- tekniset työt hoidettiin muiden työtehtävien ohessa. Tietotekniset tehtävät olivat lähinnä tukitoimintoihin liittyviä tehtäviä. Kasvuvaiheessa tietotekniikan merkitys kasvoi, ja Trafotekiin tuli tarvetta luoda erillinen tietotekninen työtehtävä. Tässä toiminnan vaiheessa kyvykkyydet ja kypsyys eivät kuitenkaan kehittyneet halu- tulla tavalla, sillä kaikki käytössä oleva resursointi käytettiin edelleen päivittäisiin tukitoimintoihin, kehittämisen sijaan. Sama kehittymättömyys vaivasi toiminnan kypsässä vaiheessa. Tässä vaiheessa toki alettiin jo ymmärtää, että tietohallinnolla on strateginen rooli, joka tukee liiketoimintaa sen tavoitteiden saavuttamisessa. Tehty tutkimus tukee näkemystä siitä, että myös tietohallinnon kehittäminen on kokonaisvaltaista kehittämistä, jossa pitää huomioida toimintaa tukevia kyvyk- kyyksiä kaikissa toiminnan vaiheissa. Yrityksen kasvaessa myös tietohallinnon tu- lee kasvaa ja kehittyä. Osa tämän tutkimuksen tapahtumista oli tapahtunut ennen tämän tutkimustyön varsinaista aloittamista, eli ne kuvataan ja selitetään jälkijättöisesti. Kyseessä on toimintatutkimus, joka ajoittuu vuosiin 1996–2014. Avainsanat: globalisaatio, kansainvälinen kasvu, tietohallinto, tietohallinnon joh- taminen ja kehitys, kasvu-, kehitys- ja kypsyysmalli
Resumo:
This paper aims at presenting and discussing some of behavioral models developed by Economic Psychology which is considered an irrelevant field of research for many economists yet. On highlighting the multidisciplinary convergence notably from economists' interests by psychology, it is done emphasis to the discussion of the role played by methodological individualism in the psychological reduction of the homo economicus. Such a reduction has, on the one hand, made harder the conciliation between the individual and the collective level of analysis. On the other hand, it made closer economists and psychologists in the common interest of developing methods capable of understanding the economic behavior under a perspective which allows the integration of the complexity of collective dimension in which the individual makes part.
Resumo:
The 5a-reductase of Penicillium decumbens ATCC 10436 was used as a model for the mammalian enzyme to investigate the mechanism of reduction of testosterone to 5adihydrotestosterone . The purpose of this study was to search for specific 5a-reductase inhibitors which antagonize prostate cancer . In a whole-cell biotransformation mode, this organism reduced testosterone (1) to 5a-dihydrosteroids (8) and 5aandrostane- 3, 17-dione (9) in yields of 28% and 37% respectively. Control experiments have shown that 5aandrostane- 3, 17-dione (9) can be produced from the corresponding alcohol (8) in a subsequent reaction separate from that catalysed by the 5a-reductase enzyme . Androst-4- ene-3, 17-dione (2) is reduced to give only (9) with a recovery of 80% The stereochemistry of the reduction was determined by 500 MHz ^H NMR analysis of the products resulting from the deuterium labelled substrates. The results were obtained by an analysis of the NOE difference spectra, double-quantum filtered phase sensitive COSY 2-D spectra, and ^^c-Ir 2-D shift correlation spectra of deuterium labelled products. According to the unambiguous assignment of the signals due to H-4a and H-4Ii in 5a-dihydro steroids, the NMR data show clearly that addition of hydrogen to the 4{5)K bond has occurred in a trans manner at positions 413 and 5a. To Study the reduction mechanism of this enzyme, several substrates were prepared as following; 3-methyleneandrost-4-en- 17fi-ol(3), androst-4-en-17i5-ol(5) , androst-4-en-3ii, 17fi-diol (6) and 4, 5ii-epoxyandrostane-3, 17-dione (7) . Results suggest that this enzyme system requires an oxygen atom at the 3-position of the steroid in order to bind the substrate. Furthermore, the mechanism of this 5a-reductase may proceed via direct addition of hydrogen at the 4,5 position without involvement of a carbonyl group as an intermediate.
Resumo:
Patterns of intra-clutch egg size variation and intra-clutch hatch intervals in the Ring-billed gull (Larus delawarensis) were documented during the peak nesting period of two consecutive breeding seasons, at a colony near Port Colborne, Ontario. Egg size decreased with laying order; third laid eggs were significantly smaller than first laid eggs. Hatching of the third egg was delayed from that of first and second eggs. Intraclutch egg size differences established initial size disparities among chicks at hatch. Hatch intervals further exaggerated size disparities during the early post brood completion period. Competitive asymmetries among chicks were associated with increased mortality rates among third hatched chicks despite the lack of evidence of a sibling feeding hierarchy. Fledging success in 1987 was greater than in 1988. A "brood reduction strategy" appears to have enabled parents in 1987, to obtain an extra unit of reproductive fitness, while in 1988 parents were often unable to raise the entire brood and third chicks likely represented insurance reproductive value. Experimental broods (1988) were created in which hatch intervals were double those of natural intervals. The size disparities among chicks were significantly greater than in control broods, and the pattern of mortality among chicks suggested that first chicks benefited at a cost to second and third chicks. Parents of peak experimental broods achieved a fledging success rate similar to that of control broods. Characteristics of chick adoptions were also recorded. In each study year, 9 chicks abandoned their natal territories, 6 of which were adopted. Chicks consistently established themselves into broods where they were older than resident chicks. No direct evidence of cost to foster parents, or benefits to adopted chicks was obtained, although fledging success of adopted chicks was high.
Resumo:
Fresh egg-weights and feeding rates to chicks were related to chick survival as one means of quantifying apportionment of parental investment wi thin broods of Caspian Terns (SterDI casRla) at a colony in Georgian Bay. Lake Huron, during 1978 and 1979. Ftrst-laid eggs from 2-egg clutches were Significantly heavier and usually hatched one to three days earlier than second-laid eggs in both years of the study. In both years, first-hatched chicks were larger and generally better fed than second-hatched siblings. The disparity between feedIng rates of first- and second-hatched ehicks was greater in 1979. Brood feeding I rates correlated positively with the percentage of food fed to the least-fed sibUng through the period of B-chick ages zero to 10 days in 1978. I suggest that after this age period, parental control over whlcb cbick was fed diminished. In 1978, 10 of 16 secondhatched chicks were fed more than their older siblings during their first 5 days. 'lb.is is interpreted as a parental response to reduce the competitive advantage of the larger first-hatched chicks. Most chick losses were apparently caused by starvation or preda. tion. In 1979, seeorvl-hatched chick disappearance (due to predation) was -related to low feeding rates, whereas first-hatched chick disappearance was related to low fresh egg-weights.. First-hatched chicks survived better than second-hatched chicks both years, and more pairs fledged two chicks in 1978. Maximum estimated feeding rates at the nest and fledging ages suggested that food was more avatlable in 1978 than in 1979. In 1979, second eggs apparently functioned as "insurance" eggs. When the first-laid egg falled to hatch, or the first-hatched chick died, the second-hatched chick was often successfully fledged. When first-hatched chicks survived, the second-hatched chick usually starved or was preyed upon, reducing the brood to one chick. Parental investment patterns favored first-hatched chicks. Brood reduction, when employed, discouraged total nest failure, however, under appropriate conditions, brood reduction was avoided and full broods (or two chicks) were fledged.
Resumo:
This work includes two major parts. The first part of the work concentrated on the studies of the application of the highperfonnance liquid chromatography-particle beam interface-mass spectrometry system of some pesticides. Factors that have effects on the detection sensitivity were studied. The linearity ranges and detection limits of ten pesticides are also given in this work. The second part of the work concentrated on the studies of the reduction phenomena of nitro compounds in the HPLC-PB-MS system. Direct probe mass spectrometry and gas chromatography-mass spectrometry techniques were also used in the work. Factors that have effects on the reduction of the nitro compounds were studied, and the possible explanation is proposed. The final part of this work included the studies of reduction behavior of some other compounds in the HPLC-PB-MS system, included in them are: quinones, sulfoxides, and sulfones.
Resumo:
The effects of a complexly worded counterattitudinal appeal on laypeople's attitudes toward a legal issue were examined, using the Elaboration Likelihood Model (ELM) of persuasion as a theoretical framework. This model states that persuasion can result from the elaboration and scrutiny of the message arguments (i.e., central route processing), or can result from less cognitively effortful strategies, such as relying on source characteristics as a cue to message validity (i.e., peripheral route processing). One hundred and sixty-seven undergraduates (85 men and 81 women) listened to eitller a low status or high status source deliver a counterattitudinal speech on a legal issue. The speech was designed to contain strong or weak arguments. These arguments were 'worded in a simple and, therefore, easy to comprehend manner, or in a complex and, therefore, difficult to comprehend manner. Thus, there were three experimental manipulations: argument comprehensibility (easy to comprehend vs. difficult to comprehend), argumel11 strength (weak vs. strong), and source status (low vs. high). After listening to tIle speec.J] participants completed a measure 'of their attitude toward the legal issue, a thought listil1g task, an argument recall task,manipulation checks, measures of motivation to process the message, and measures of mood. As a result of the failure of the argument strength manipulation, only the effects of the comprehel1sibility and source status manipulations were tested. There was, however, some evidence of more central route processing in the easy comprehension condition than in the difficult comprehension condition, as predicted. Significant correlations were found between attitude and favourable and unfavourable thoughts about the legal issue with easy to comprehend arguments; whereas, there was a correlation only between attitude and favourable thoughts 11 toward the issue with difficult to comprehend arguments, suggesting, perhaps, that central route processing, \vhich involves argument scrutiny and elaboration, occurred under conditions of easy comprehension to a greater extent than under conditions of difficult comprehension. The results also revealed, among other findings, several significant effects of gender. Men had more favourable attitudes toward the legal issue than did women, men recalled more arguments from the speech than did women, men were less frustrated while listening to the speech than were ,vomen, and men put more effort into thinking about the message arguments than did women. When the arguments were difficult to comprehend, men had more favourable thoughts and fewer unfavourable thoughts about the legal issue than did women. Men and women may have had different affective responses to the issue of plea bargaining (with women responding more negatively than men), especially in light of a local and controversial plea bargain that occurred around the time of this study. Such pre-existing gender differences may have led to tIle lower frustration, the greater effort, the greater recall, and more positive attitudes for men than for WOlnen. Results· from this study suggest that current cognitive models of persuasion may not be very applicable to controversial issues which elicit strong emotional responses. Finally, these data indicate that affective responses, the controversial and emotional nature ofthe issue, gender and other individual differences are important considerations when experts are attempting to persuade laypeople toward a counterattitudinal position.
Resumo:
A cardiovascular disease risk factor reduction program was implemented in the Niagara region. To gain an understanding of this program from the participants ' perspective, 10 participants of the program were interviewed to document their perceptions of what they learned in the program, their perceptions of their behaviour change and their perceptions of factors that facilitated or impeded any behaviour change. The learning style inventory and PET test were also given to the participants to further understand their perceptions. Findings unique to this study highlighted aspects of the andragogical model, self-directed learning theory, learning style preference and psychological type that were prominent in the participants' comments and perspectives. Implications for practice, theory development and further research are suggested.