962 resultados para Canonical average
Resumo:
Papaya (Carica papaya L.) is a typical crop of tropical areas, and Brazil is one of the leading world producers. In recent decades, papaya culture has expanded to different regions of the country, but the number of cultivars available is still limited. In the present study, a complete diallel cross was carried out using eight accessions of papaya from the UENF/Caliman germplasm bank. Four genotypes belong to the Formosa heterotic group and four, to the Solo group. This study aimed to evaluate the occurrence and viability of exploring heterosis in heterotic intragroup hybrids. Fifty-six hybrid progenies were generated and evaluated. Among the Formosa intragroup hybrids, two hybrid combinations (MR x J4 and MR x SK) showed heterosis for all traits, as well as good average total fruit production. Among the Solo intragroup hybrids, three hybrid combinations (WM x GG, WM x SS and WM x SM) stand out for fruit production and high content of soluble solids. In Formosa x Solo hybrids, all hybrid combinations with the parent JS (JS x WM, JS x GG, JS x SS and JS x SM) showed high fruit quality and good average for fruit production. The heterotic profile of the hybrids tested allowed the identification of promising hybrids within Formosa and Solo heterotic groups. The analysis of the canonical variables also allowed the visualization of distinct groups of hybrids, depending on the provenance of the parents.
Resumo:
The scaling of body parts is central to the expression of morphology across body sizes and to the generation of morphological diversity within and among species. Although patterns of scaling-relationship evolution have been well documented for over one hundred years, little is known regarding how selection acts to generate these patterns. In part, this is because it is unclear the extent to which the elements of log-linear scaling relationships-the intercept or mean trait size and the slope-can evolve independently. Here, using the wing-body size scaling relationship in Drosophila melanogaster as an empirical model, we use artificial selection to demonstrate that the slope of a morphological scaling relationship between an organ (the wing) and body size can evolve independently of mean organ or body size. We discuss our findings in the context of how selection likely operates on morphological scaling relationships in nature, the developmental basis for evolved changes in scaling, and the general approach of using individual-based selection experiments to study the expression and evolution of morphological scaling.
Resumo:
A continuous random variable is expanded as a sum of a sequence of uncorrelated random variables. These variables are principal dimensions in continuous scaling on a distance function, as an extension of classic scaling on a distance matrix. For a particular distance, these dimensions are principal components. Then some properties are studied and an inequality is obtained. Diagonal expansions are considered from the same continuous scaling point of view, by means of the chi-square distance. The geometric dimension of a bivariate distribution is defined and illustrated with copulas. It is shown that the dimension can have the power of continuum.
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The thesis examines the profitability of DMAC trading rules in the Finnish stock market over the 1996-2012 period. It contributes to the existing technical analysis literature by comparing for the first time the performance of DMAC strategies based on individual stock trading portfolios to the performance of index trading strategies based on the trading on the index (OMX Helsinki 25) that consists of the same stocks. Besides, the market frictions including transaction costs and taxes are taken into account, and the results are reported from both institutional and individual investor’s perspective. Performance characteristic of DMAC rules are evaluated by simulating 19,900 different trading strategies in total for two non- overlapping 8-year sub-periods, and decomposing the full-sample-period performance of DMAC trading strategies into distinct bullish- and bearish-period performances. The results show that the best DMAC rules have predictive power on future price trends, and these rules are able to outperform buy-and-hold strategy. Although the performance of the DMAC strategies is highly dependent on the combination of moving average lengths, the best DMAC rules of the first sub-period have also performed well during the latter sub-period in the case of individual stock trading strategies. According to the results, the outperformance of DMAC trading rules over buy-and-hold strategy is mostly attributed to their superiority during the bearish periods, and particularly, during stock market crashes.
Resumo:
Kalciumjonen reglerar flera processer i celler såsom transkribering av gener, celldelning, cellernas rörlighet och celldöd. Därför har cellerna utvecklat många mekanismer för att reglera den intracellulära kalciumkoncentrationen. Kalciumkanaler spelar en viktig roll i denna regleringsprocess. TRPC-kanalerna (eng. canonical transient receptor potential) är en familj av jonkanaler med sju medlemmar (TRPC1-7) vars regleringsmekanismer och fysiologiska roller är varierande. TRPC2-kanalens fysiologiska signifikans, samt hur kanalen regleras, är dåligt karakteriserad. För första gången, rapporterar vi närvaron av TRPC2 kanalen i råttans sköldkörtelceller samt primära sköldkörtelceller från råtta. Hos gnagare har TRPC2 antagits vara exklusivt uttryckt i det vomeronasala organet. För att undersöka den fysiologiska betydelsen av kanalen, har vi utvecklat stabila celler med nedreglerat TRPC2 (shTRPC2) m.h.a. shRNA-teknik. Nedreglering av TRPC2 resulterade i stora skillnader i flera viktiga cellulära funktioner och i regleringen av sköldkörtelcellernas cellsignalering. Nedreglering av TRPC2 orsakade minskad agonist-beroende frigivning av kalcium från det endoplasmatiska nätverket, samt minskat agonist-beroende inflöde av extracellulärt kalcium, men ökade det basala kalciuminflödet. Uttrycket av PKCβ1 och PKCδ, SERCA-aktiviteten och kalciumhalten i det endoplasmatiska nätverket minskade i shTRPC2 celler. Kommunikation mellan kalcium- och cAMP-signalering påvisades vara TRPC2-beroende, vilket visades reglera uttrycket av TSH-receptorn. Vi undersökte också betydelsen av TRPC2 kanalen i reglering av sköldkörtelcellers proliferation, migration, vidhäftning och invasion; processer som alla var dämpade i shTRPC2 celler. Samamnfattningsvis påvisade dessa resultat en ny och viktig fysiologisk betydelse för TRPC2 kanalerna.
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Exact correlation coefficients between a canonical variate and measured traits were derived to evaluate genetic divergence among varieties. This method allows the plant breeder to determine which traits contribute significantly to genetic divergence and, also, to identify the most important among them. An example is presented, related to a trial where 28 varieties of maize were evaluated for two traits
Resumo:
Inhibition of type-5 phosphodiesterase by sildenafil decreases capacitative Ca2+ entry mediated by transient receptor potential proteins (TRPs) in the pulmonary artery. These families of channels, especially the canonical TRP (TRPC) subfamily, may be involved in the development of bronchial hyperresponsiveness, a hallmark of asthma. In the present study, we evaluated i) the effects of sildenafil on tracheal rings of rats subjected to antigen challenge, ii) whether the extent of TRPC gene expression may be modified by antigen challenge, and iii) whether inhibition of type-5 phosphodiesterase (PDE5) may alter TRPC gene expression after antigen challenge. Sildenafil (0.1 µM to 0.6 mM) fully relaxed carbachol-induced contractions in isolated tracheal rings prepared from naive male Wistar rats (250-300 g) by activating the NO-cGMP-K+ channel pathway. Rats sensitized to antigen by intraperitoneal injections of ovalbumin were subjected to antigen challenge by ovalbumin inhalation, and their tracheal rings were used to study the effects of sildenafil, which more effectively inhibited contractions induced by either carbachol (10 µM) or extracellular Ca2+ restoration after thapsigargin (1 µM) treatment. Antigen challenge increased the expression of the TRPC1 and TRPC4 genes but not the expression of the TRPC5 and TRPC6 genes. Applied before the antigen challenge, sildenafil increased the gene expression, which was evaluated by RT-PCR, of TRPC1 and TRPC6, decreased TRPC5 expression, and was inert against TRPC4. Thus, we conclude that PDE5 inhibition is involved in the development of an airway hyperresponsive phenotype in rats after antigen challenge by altering TRPC gene expression.
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Wnt proteins are involved in tissue development and their signaling pathways play an important role during embryogenesis. Wnt signaling can promote cell survival, which is beneficial for neurons, but could also lead to tumor development in different tissues. The present study investigated the effects of a Wnt protein on the susceptibility of a neural tumor cell line (PC12 cells) to the cytotoxic compounds ferrous sulfate (10 mM), staurosporine (100 and 500 nM), 3-nitropropionic acid (5 mM), and amyloid β-peptide (Aβ25-35; 50 µM). Cells (1 x 10(6) cells/mL) were treated with the Wnt-3a recombinant peptide (200 ng/mL) for 24 h before exposure to toxic insults. The Wnt-3a protein partially protected PC12 cells, with a 6-15% increase in cell viability in the presence of toxic agents, similar to the effect measured using the MTT and lactate dehydrogenase cell viability assays. The Wnt-3a protein increased protein expression of β-catenin by 52% compared to control. These findings suggest that Wnt signaling can protect neural cells against apoptosis induced by toxic agents, which are relevant to the pathogenesis of Alzheimer’s and Huntington’s diseases.
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Exposure to air pollutants is associated with hospitalizations due to pneumonia in children. We hypothesized the length of hospitalization due to pneumonia may be dependent on air pollutant concentrations. Therefore, we built a computational model using fuzzy logic tools to predict the mean time of hospitalization due to pneumonia in children living in São José dos Campos, SP, Brazil. The model was built with four inputs related to pollutant concentrations and effective temperature, and the output was related to the mean length of hospitalization. Each input had two membership functions and the output had four membership functions, generating 16 rules. The model was validated against real data, and a receiver operating characteristic (ROC) curve was constructed to evaluate model performance. The values predicted by the model were significantly correlated with real data. Sulfur dioxide and particulate matter significantly predicted the mean length of hospitalization in lags 0, 1, and 2. This model can contribute to the care provided to children with pneumonia.
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Generation Y is entering the workforce in large numbers and, because this generation holds different values than previous generations, accounting firms are having difficulty managing these new hires. I t is important to determine whether Generation Y is associated with meaningful, long-term trends or i f they will adapt to the given situation. Gen Y' s association with average hours worked per person and average salaries in the Canadian Accounting, Marketing, and Legal professions is examined. I find that an increasing percentage of Generation Y employees in the workforce is associated with significant decreases in average hours worked, but is not associated with any significant trend in average salary. I t is concluded that Generation Y is associated with changing trends in the workplace. These trends are contrary to wha t might be expected under traditional definitions of success, therefore it is postulated that Gen Y may view workplace success differently than previous generations.
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The Average White Band's debut album, Show your hand, was released in 1973. The "classic funk and R & B" band included members Alan Gorrie, Owen "Onnie" McIntyre, Malcolm "Mollie" Duncan, Roger Ball, Robbie McIntosh, and Mike Rosen. Rosen was quickly replaced by Hamish Stuart. The band, comprised of Scotsmen, released a second album in 1974 that featured the US number 1/UK Top 10 single "Pick up the Pieces". That same year, Robbie McIntosh died of a heroin overdose and was replaced by Steve Ferrone. The song "Cut the Cake" from their third album made the US top 10, and subsequent releases in the late 1970s and early 1980s proved successful. The members largely pursued individual projects in the years that followed, but re-formed in 1989 (with original members Gorrie, Ball and McIntyre, and new members Alex Ligertwood and Eliot Lewis) and released the album Aftershock. Over the years, the band's members have changed, and the band is currently comprised of Onnie McIntyre, Rocky Bryant, Alan Gorrie, Fred "Freddy V" Vigdor and Klyde Jones. Their most recent album, Times Squared, was released in 2009.