985 resultados para DETERMINANT


Relevância:

10.00% 10.00%

Publicador:

Resumo:

Long-distance bird migration consists of several flight episodes interrupted by a series of resting and refuelling periods on stopover sites. We assessed the role of food availability as the determinant of staging decisions focusing on the following three aspects of food availability: intake rates, stochasticity in intake rates and onset of spring. Using stochastic dynamic modelling, we investigated their impact on staging times and expected fitness. Subsequently, we compared relations in the use of the stopover sites as predicted by the model with empirical data of the Svalbard-breeding population of Pink-footed Goose Anser brachyrhynchus collected in the period 1990–2002. Our results indicate that, for the case of Pink-footed Geese, spring phenology determines a major part of the migration schedule. In contrast to our expectations, intake rates were generally only of minor importance; however, when approaching the breeding grounds their significance increased. Expected fitness at arrival on the breeding grounds showed that the geese can compensate for changes in a broad range of food availability and also cope with varying degrees of stochasticity. However, declining intake rates at the last stopover site or very late onsets of spring clearly decreased fitness. As predicted by the model, the use of stopover sites was interdependent – from empirical data we derived negative relationships between the staging durations of subsequent sites. These results lend credit to an integrated spatially explicit approach focussing on multiple stopover site characteristics when attempting to improve our understanding of bird migration.

Relevância:

10.00% 10.00%

Publicador:

Resumo:

Objective : A person's health literacy, i.e., their ability to seek, understand and use health information, is a critical determinant of whether they are able to actively participate in their healthcare. The objective of this study was to conceptualise health literacy from the patient perspective.

Methods : Using comprehensive qualitative methods 48 individuals were interviewed across three distinct groups in Australia: those with a chronic condition, the general community and individuals who had recently presented to a metropolitan public hospital emergency department. Purposeful sampling was employed to ensure a range of experiences was captured.

Results : Seven key abilities were identified: knowing when to seek health information; knowing where to seek health information; verbal communication skills; assertiveness; literacy skills; capacity to process and retain information; application skills.

Conclusion : This study identifies key abilities patients identified as critical to seek, understand and utilise information in the healthcare setting. These abilities are not reflected in existing measures for health literacy. Future measures of health literacy could consider incorporating abilities identified in this study and may provide guidance in developing health interventions to assist patients to participate effectively in their health.

Practice implications :
More comprehensive measures to assess patient's health literacy are needed.

Relevância:

10.00% 10.00%

Publicador:

Resumo:

This study examines the underpricing cost of 123 US REIT IPOs over the period 1996 until June 2010, including the period of the global financial crisis. The study uses OLS multivariate regression to determine some potential factors behind underpricing. The underpricing cost of raising REIT external equity averaged 3.18% using an equal weighting for each of the 123 REIT IPOs. The study finds offer size is positively related to underpricing. A value weighted approach finds that underpricing averages 4.67% and suggests larger offer size is an important determinant for leaving more money on the table. Higher reputation underwriters, the industry differentiated auditor and post offer ownership structure negatively influence underpricing. The study documents declining underpricing over time with the period of 2007–2010 experiencing negative underpricing (overpricing) during the global financial crisis (GFC). Offers during the hot periods of 1997 and 2004 and the office/industrial property type were more highly underpriced. The 10-year treasury interest rate is identified as another significant positive determinant of underpricing.

Relevância:

10.00% 10.00%

Publicador:

Resumo:

We have identified a major allergenic protein from rye-grass pollen, tentatively designated Lol pIb of 31kDa and with pI 9.0. A cDNA clone encoding Lol pIb has been isolated, sequenced, and characterized. Lol pIb is located mainly in the starch granules. This is a distinct allergen from Lol pI, which is located in the cytosol. Lol pIb is synthesized in pollen as a pre-allergen with a transit peptide targeting the allergen to amyloplasts. Epitope mapping of the fusion protein localized the IgE binding determinant in the C-terminal domain.

Relevância:

10.00% 10.00%

Publicador:

Resumo:

Chemoprevention by dietary constituents in the form of functional food has emerged as a novel approach to control inflammatory diseases and cancers. Recently we reported for the first time that iron content is a critical determinant in the anti-tumour activity of bovine milk lactoferrin (bLf). We therefore wanted to evaluate the chemo-preventative efficacy of Apo-bLF and 100% iron-saturated bLF (Fe-bLF) on hydrogen peroxide (H2O 2)-induced colon carcinogenesis, and their influence on antioxidant enzyme activities within colon carcinogenesis. This was undertaken through observing how oxidative stress induced by H2O2 alters antioxidant enzyme activity within HT29 colon cancer cells, and then observing changes in this activity by treatments with the different antioxidants ascorbic acid (AA), Apo-bLF and Fe-bLF. All antioxidant enzymes (catalase, glutathione peroxidase (GPx), glutathione reductase (GR), glutathione-s-transferase (GsT) and superoxide dismutase (SOD)) appeared to be increased within HT29 cells, even prior to H2O2 exposure, and all enzymes showed significant decreased activity when cells were treated with the antioxidants AA, Apo-bLF or Fe-bLF, with or without H2O2 exposure. The results indicate that all three antioxidants have the ability to scavenge ROS, lower antioxidant enzyme activities within already excited states, and possibly allow colon cancer cells to be overcome by oxidative stress that would normally be prevented, perhaps leading to damage and potential apoptosis of the cancer cells. In conclusion, the anti-oxidative effects of Apo-bLF and Fe-bLf studied for the first time, show dynamic changes that may allow for necessary protection from imbalanced oxidative conditions, and potential at reducing the ability of cancer cells to protect themselves from oxidative stress states.

Relevância:

10.00% 10.00%

Publicador:

Resumo:

An experiment is described in which a mica surface is driven towards a mercury drop immersed in aqueous electrolyte. Under appropriate conditions, hydrodynamic pressure in the aqueous film creates a classical dimple in the mercury drop. The use of optical interferometry and video recording to monitor the shape of the drop and the thickness of the aqueous film with sub-nanometre resolution yields a high density of precise data showing the formation and evolution of the dimple as the film drains. Variation of electrical potential applied to the mercury phase allows control of the surface forces acting between the drop and the mica surface, so that the effect of surface forces on the film drainage process is highlighted. It is found that the film thickness at the centre of the dimple and the lateral extent of the dimple are not significantly affected by surface forces. On the other hand, the minimum film thickness at the edge of the dimple is sensitive even to weak surface forces. Since this minimum film thickness is a major determinant of the film drainage rate, it is shown that surface forces have an important effect on the overall drainage process.

Relevância:

10.00% 10.00%

Publicador:

Resumo:

We investigate and compare the determinants of US and Australian interest rate swap spreads and the linkages between these markets. The slope of the risk-free term structure is the most significant determinant and its importance is greater for longer terms to maturity. Interest rate levels and, in Australia, the default premium also have some impact. The influences of interest rate volatility, the liquidity premium and (in the USA) the default premium are small or negligible. We hypothesise, and our evidence confirms, that the US swap market significantly affects the Australian swap market but not vice-versa.

Relevância:

10.00% 10.00%

Publicador:

Resumo:

In this paper, we propose a maximum contrast analysis (MCA) method for nonnegative blind source separation, where both the mixing matrix and the source signals are nonnegative. We first show that the contrast degree of the source signals is greater than that of the mixed signals. Motivated by this observation, we propose an MCA-based cost function. It is further shown that the separation matrix can be obtained by maximizing the proposed cost function. Then we derive an iterative determinant maximization algorithm for estimating the separation matrix. In the case of two sources, a closed-form solution exists and is derived. Unlike most existing blind source separation methods, the proposed MCA method needs neither the independence assumption, nor the sparseness requirement of the sources. The effectiveness of the new method is illustrated by experiments using X-ray images, remote sensing images, infrared spectral images, and real-world fluorescence microscopy images.

Relevância:

10.00% 10.00%

Publicador:

Resumo:

Cancer and many chronic inflammatory diseases are associated with increased amounts of reactive oxygen species (ROS). The potential cellular and tissue damage created by ROS has significant impact on many disease and cancer states and natural therapeutics are becoming essential in regulating altered redox states. We have shown recently that iron content is a critical determinant in the antitumour activity of bovine milk lactoferrin (bLF). We found that 100% iron-saturated bLF (Fe-bLF) acts as a potent natural adjuvant and fortifying agent for augmenting cancer chemotherapy and thus has a broad utility in the treatment of cancer. Furthermore, we also studied the effects of iron saturated bLF's ability as an antioxidant in the human epithelial colon cancer cell line HT29, giving insights into the potential of bLF in its different states. Thus, metal saturated bLF could be implemented as anti-cancer neutraceutical. In this regard, we have recently been able to prepare a selenium (Se) saturated form of bLF, being up to 98% saturated. Therefore, the objectives of this study were to determine how oxidative stress induced by hydrogen peroxide (H2O2) alters antioxidant enzyme activity within HT29 epithelial colon cancer cells, and observe changes in this activity by treatments with different antioxidants ascorbic acid (AA), Apo (iron free)-bLF and selenium (Se)-bLF. The states of all antioxidant enzymes (glutathione peroxidase (GPx), glutathione reductase (GR), glutathione-s-transferase (GsT), catalase and superoxide dismutase (SOD)) demonstrated high levels within untreated HT29 cells compared to the majority of other treatments being used, even prior to H2O2 exposure. All enzymes showed significant alterations in activity when cells were treated with antioxidants AA, Apo-bLF or Se-bLF, with and/or without H2O2 exposure. Obvious indications that the Se content of the bLF potentially interacted with the glutathione (GSH)/GPx/GR/GsT associated redox system could be observed immediately, showing capability of Se-bLF being highly beneficial in helping to maintain a balance between the oxidant/antioxidant systems within cells and tissues, especially in selenium deficient systems. In conclusion, the antioxidative defence activity of Se-bLf, investigated in this study for the first time, shows dynamic adaptations that may allow for essential protection from the imbalanced oxidative conditions. Because of its lack of toxicity and the availability of both selenium and bLF in whole milk, Se-bLF offers a promise for a prospective natural dietary supplement, in addition to being an immune system enhancement, or a potential chemopreventive agent for cancers.

Relevância:

10.00% 10.00%

Publicador:

Resumo:

Translators are often recommended to highly observe the natural flow of the target language of the translated texts. The use and order of discoursal aspects of texts such as thematic information, topical elements, left-dislocation, and passive voice, among others, which constitute information structure may sometimes conflict with this viewpoint. It is argued that such discoursal elements are determinant in understanding the flow of the texts in the source language and should not, therefore, be frequently switched around in the translated texts to fit the norm of the target language. The order of these linguistic elements should be maximally maintained when translating a text into a target language. It is after all the employment of such information structure units by the writer of the source text which is significant at any given point in discourse both cognitively, when processing the text, and interactionally, when communicating with the reader.

Relevância:

10.00% 10.00%

Publicador:

Resumo:

As mean fibre diameter (MFD) is the primary determinant of mohair price we aimed to quantify the lifetime changes in mohair MFDas Angora goats aged and grew. Measurements were made over 12 shearing periods on a population of Angora goats representing the current range and diversity of genetic origins including South African, Texan and interbred admixtures of these and Australian sources. Records of sire, dam, birthweight, birth parity, liveweight, fleece growth and fleece quality were taken for does and castrated males (wethers) (n = 267 animals). Fleece-free liveweights (FFLwt) were determined for each goat at shearing time by subtracting the greasy fleece weight from the liveweight recorded immediately before shearing. A restricted maximum likelihood growth curve model was developed for relating MFD to FFLwt, age and other measurements.Asimple way of describing the results is:MFD= k (FFLwt)b E; where k is a parameter that can vary in a systematic way with shearing(age), breed, weaning weight, sire, dam and individual; b is a parameter that is the same for nearly the whole study; and E are independent errors from a log-normal distribution. The analysis shows that ^b = 0.34, with s.e. (^b) = 0.021. Thus, mohair MFD was allometrically related to the cube root of FFLwt over the lifetime of Angora goats. However, the allometric proportionality constant differed in a systematic way with age at shearing, genetic strain, weaning weight, sire, dam and individual. For Texan-breed goats, MFD decreased as weaning weight increased (P = 0.00016). The findings indicate that management factors that affect liveweight and weaning weight have lifetime effects on mohair fibre diameter and therefore the value of mohair and the profitability of the mohair enterprise.

Relevância:

10.00% 10.00%

Publicador:

Resumo:

Background : Nutrition and physical activity are major determinants of health and quality of life; however, there exists little research focusing on determinants of these behaviours in older adults. This is important, since just as these behaviours vary according to subpopulation, it is likely that the determinants also vary. An understanding of the modifiable determinants of nutrition and physical activity behaviours among older adults to take into account the specific life-stage context is required in order to develop effective interventions to promote health and well-being and prevent chronic disease and improve quality of life.

Methods : The aim of this work is to identify how intrapersonal, social and environmental factors influence nutrition and physical activity behaviours among older adults living in urban and rural areas. This study is a cohort study of adults aged 55-65 years across urban and rural Victoria, Australia. Participants completed questionnaires at baseline in 2010 and will complete follow-up questionnaires in 2012 and 2014. Self-report questionnaires will be used to assess outcomes such as food intake, physical activity and sedentary behaviours, anthropometry and quality of life. Explanatory variables include socioeconomic position, and measures of the three levels of influence on older adults' nutrition and physical activity behaviours (intrapersonal, social and perceived environmental influences).

Discussion : Obesity and its determinant behaviours, physical inactivity and poor diet are major public health concerns and are significant determinants of the quality of life among the ageing population. There is a critical need for a better understanding of the determinants of nutrition and physical activity in this important target group. This research will provide evidence for the development of effective policies and programs to promote and support increased physical activity and healthy eating behaviours among older adults.

Relevância:

10.00% 10.00%

Publicador:

Resumo:

Purpose – The purpose of this paper is to investigate the total direct costs of raising external equity capital for US real estate investment trust (REIT) initial public offerings (IPOs).

Design/methodology/approach – The study provides recent evidence on total direct costs for a comprehensive dataset of 125 US REIT IPOs from 1996 until June 2010. A multivariate OLS regression is performed to determine significant factors influencing the level of total direct costs and also underwriting fees and non-underwriting direct expenses.

Findings – The study finds economies of scale in total direct costs, underwriting fees and non-underwriting expenses. The equally (value) weighted average total direct costs are 8.33 percent (7.52 percent), consisting of 6.49 percent (6.30 percent) underwriting fees and 1.87 percent (1.22 percent) non-underwriting direct expenses. The study finds a declining trend of total direct costs for post 2000 IPOs which is attributed to the declining trend in both underwriting fees and non-underwriting direct expenses. Offer size is a critical determinant for both total direct costs and their individual components and inversely affects these costs. The total direct costs are found significantly higher for equity REITs than for mortgage REITs and are also significantly higher for offers listed in New York Stock Exchange (NYSE). Underwriting fees appear to be negatively influenced by the offer price, the number of representative underwriters involved in the issue, industry return volatility and the number of potential specific risk factors but positively influenced by prior quarter industry dividend yield and ownership limit identified in the prospectus. After controlling for time trend, the paper finds REIT IPOs incur higher non-underwriting direct expenses in response to higher industry return volatility prior to the offer.

Originality/value – This paper adds to the international REIT IPO literature by exploring a number of new influencing factors behind total direct costs, underwriting fees and non-underwriting direct expenses. The study includes data during the recent GFC period.

Relevância:

10.00% 10.00%

Publicador:

Resumo:

While white cashmere is preferred by processors, its whiteness and brightness is affected by country of origin, amino acid composition, nutrition and cashmere production of goats. This work aimed to quantify the factors which affect the whiteness and brightness of 36 batches of processed Australian white cashmere sourced from nine different farms. The cashmere was tested for tristimulus values brightness (Y) and whiteness, as measured by yellowness (Y-Z). Linear models, relating Y and Y-Z were fitted to farm of origin and other objective measurements. Mean attributes (range) were: mean fibre diameter, 16.9 µm (13.9–20.4 μm); fibre curvature, 45°/mm (31–59°/mm); clean washing yield, 91.3% (79.5–97.3%); Y, 78.7 (74.7–82.2); Y-Z, 11.9 (10.3–13.6). Farm alone accounted for 72% of the variation in Y and 65% of the variation in Y-Z (P < 0.001). Once farm had been taken into account only fibre curvature (P = 0.003) was significant in predicting Y and only clean washing yield (P = 0.047) affected Y-Z. Neither the proportion of the fleece present as guard hair (clean cashmere yield) nor cashmere staple length was a significant determinant of Y or Y-Z. For each 10°/mm increase in fibre curvature Y increased 1.3 units. For each 10% increase in clean washing yield Y-Z declined 0.9 units. Variations in Y and Y-Z among farms were probably related to differences in geographic and climatic conditions and were significantly correlated to cashmere production. The effect of clean washing yield was probably related to a reduction in suint content.


Relevância:

10.00% 10.00%

Publicador:

Resumo:

Background
Movement skill competence (e.g. the ability to throw, run and kick) is a potentially important physical activity determinant. However, little is known about the long-term impact of interventions to improve movement skills in early childhood. This study aimed to determine whether intervention preschool children were still more skill proficient than controls three years after a 10 month movement skill focused intervention: ‘Tooty Fruity Vegie in Preschools’.

Methods
Children from 18 intervention and 13 control preschools in NSW, Australia were assessed at ages four (Time1), five (T2) and eight years (T3) for locomotor (run, gallop, hop, leap, horizontal jump, slide) and object control proficiency (strike, bounce, catch, kick, overhand throw, underhand roll) using the Test of Gross Motor Development-2. Multi-level object control and locomotor regression models were fitted with variables time, intervention (yes/no) and a time*intervention interaction. Both models added sex of child and retained if significant, in which case interactions of sex of child with other variables were modelled and retained. SPSS (Version 17.0) was used.

Results
Overall follow-up rate was 29% (163/560). Of the 137 students used in the regression models, 53% were female (n = 73). Intervention girls maintained their object control skill advantage in comparison to controls at T3 (p = .002), but intervention boys did not (p = .591). At T3, there were no longer intervention/control differences in locomotor skill (p = .801).

Conclusion
Early childhood settings should implement movement skill interventions and more intensively target girls and object control skills.