961 resultados para Human body size.


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Different components of complex integrated systems may be specialized for different functions, and thus the selective pressures acting on the system as a whole may be conflicting and can ultimately constrain organismal performance and evolution. The vertebrate cranial system is one of the most striking examples of a complex system with several possible functions, being associated to activities as different as locomotion, prey capture, display and defensive behaviours. Therefore, selective pressures on the cranial system as a whole are possibly complex and may be conflicting. The present study focuses on the influence of potentially conflicting selective pressures (diet vs. locomotion) on the evolution of head shape in Tropidurinae lizards. For example, the expected adaptations leading to flat heads and bodies in species living on vertical structures may conflict with the need for improved bite performance associated with the inclusion of hard or tough prey into the diet, a common phenomenon in Tropidurinae lizards. Body size and six variables describing head shape were quantified in preserved specimens of 23 species, and information on diet and substrate usage was obtained from the literature. No phylogenetic signal was observed in the morphological data at any branch length tested, suggesting adaptive evolution of head shape in Tropidurinae. This pattern was confirmed by both factor analysis and independent contrast analysis, which suggested adaptive co-variation between the head shape and the inclusion of hard prey into the diet. In contrast to our expectations, habitat use did not constrain or drive head shape evolution in the group.

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There is a gap in terms of the supposed survival differences recorded in the field according to individual condition. This is partly due to our inability to assess survival in the wild. Here we applied modern statistical techniques to field-gathered data in two damselfly species whose males practice alternative reproductive tactics (ARTs) and whose indicators of condition in both sexes are known. In Paraphlebia zoe, there are two ART: a larger black-winged (BW) male which defends mating territories and a smaller hyaline-winged (HW) male that usually acts as a satellite. In this species, condition in both morphs is correlated with body size. In Calopteryx haemorrhoidalis, males follow tactics according to their condition with males in better condition practicing a territorial ART. In addition, in this species, condition correlates positively with wing pigmentation in both sexes. Our prediction for both species was that males practicing the territorial tactic will survive less longer than males using a nonterritorial tactic, and larger or more pigmented animals will survive for longer. In P. zoe, BW males survived less than females but did not differ from HW males, and not necessarily larger individuals survived for longer. In fact, size affected survival but only when group identity was analysed, showing a positive relationship in females and a slightly negative relationship in both male morphs. For C. haemorrhoidalis, survival was larger for more pigmented males and females, but size was not a good survival predictor. Our results partially confirm assumptions based on the maintenance of ARTs. Our results also indicate that female pigmentation, correlates with a fitness component - survival - as proposed by recent sexual selection ideas applied to females.

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The genus Candida includes different species that have the potential to invade and colonize the human body and C. albicans is the most common cause of skin, nail and mucous infections. The increasing resistance against antifungal drugs has renewed the search for new treatment procedures and antimicrobial photodynamic inactivation (PDI) is a propitious candidate. Hypericin (HY) has several wanted properties to be used as a photosensitizer in this technique including a high quantum yield of singlet oxygen generation, a high extinction coefficient near 600 nm, and a relatively low dark toxicity. Although the phototoxicity of HY on several tumor cells has been reported, the data concerning its photoactivity on microorganisms are scarce. The aim of this study was to obtain the experimental parameters to achieve an acceptable selective hypericinphotoinactivation of two species of Candida comparing with fibroblasts and epithelial cells which are the constituents of some potential host tissues, such mucosas, skin and cavities. Microorganisms and cells were incubated with the same HY concentrations and short incubation time followed by irradiation with equal dose of light. The best conditions to kill just Candida were very low HY concentration (0.1-0.4 mu g ml(-1)) incubated by 10 min and irradiated with LED 590 nm with 6 J cm(-2).

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This paper presents a computer-vision based marker-free method for gait-impairment detection in Patients with Parkinson's disease (PWP). The system is based upon the idea that a normal human body attains equilibrium during the gait by aligning the body posture with Axis-of-Gravity (AOG) using feet as the base of support. In contrast, PWP appear to be falling forward as they are less-able to align their body with AOG due to rigid muscular tone. A normal gait exhibits periodic stride-cycles with stride-angle around 45o between the legs, whereas PWP walk with shortened stride-angle with high variability between the stride-cycles. In order to analyze Parkinsonian-gait (PG), subjects were videotaped with several gait-cycles. The subject's body was segmented using a color-segmentation method to form a silhouette. The silhouette was skeletonized for motion cues extraction. The motion cues analyzed were stride-cycles (based on the cyclic leg motion of skeleton) and posture lean (based on the angle between leaned torso of skeleton and AOG). Cosine similarity between an imaginary perfect gait pattern and the subject gait patterns produced 100% recognition rate of PG for 4 normal-controls and 3 PWP. Results suggested that the method is a promising tool to be used for PG assessment in home-environment.

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Dasyurid marsupials are distributed throughout the major terrestrial environments of Australia but since European settlement have suffered local and regional extinctions, range reductions and population declines. In this paper we examine the conservation status of small dasyurids (<500 g) and the threats they face. We also evaluate recovery procedures for threatened taxa and assess their success. Twenty-four percent of smaller dasyurids are classified as vulnerable, endangered or data deficient. Large body size and occupancy of one or two habitat types are correlated strongly with  endangerment species currently considered as 'low risk, near threatened' group closely with vulnerable and endangered species, indicating a risk of further declines. The processes contributing most to declines include habitat loss and fragmentation, altered fire regimes and predation. As of April 200 I, no Recovery Plans had been adopted by the Commonwealth Govemment for any small dasyund species. There is much information on the reproduction and development of smaller dasyurids, making them suitable for captive breeding. However, captive breeding programs have been limited. the  dibbler Paranrechinus apicalis being the only species bred systematically for reintroductions. There is a need for integration between captive breeding programs and recovery planning. as well as for more information on the population viability and metapopulation structures of small dasyurids genetic diversity of populations and inbreeding depression. We suggest a program of survey. research. management and education to Improve conservation outcomes for all small dasyurids.

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The distribution and attributes of properties involved in three major programs for biodiversity protection on private land in Victoria, Australia, was investigated to determine their role in relation to the reserve system. Overlaying of dowsets in a geographic information system, with particular emphasis on property distribution in relation to bioregional and population centres, was undertaken. Land for Wildlife agreements had greater numbers of properties and total area protected in all bioregions throughout the State, yet average protected area sizes were lower than those of conservation covenants and Trust for Nature reserves. A combination of large bioregional area and human population size tended to attract more private conservation properties and, to a lesser extent, the total area they protected. The potential contribution that such properties made to biodiversity conservation varied between bioregions. Inclusion of properties within a national reserve framework is proposed to improve the coordination and effectiveness of conservation measures.

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In avian species with no obvious differences in plumage or body size between the sexes, such as penguins, discriminant function analysis (DFA) of morphometric measurements that display sexual dimorphism can provide a simple and rapid means of determining sex in the field. Like most other penguin species, the Little Penguin (Eudyptula minor) displays sexual dimorphism in bill shape and size. In the present study, discriminant functions (DFs) were developed for sexing adult Little Penguins at two colonies in northern Bass Strait, Victoria, Australia, and their accuracies were compared with those obtained previously in other parts of the species' range. Backwards stepwise DFA indicated that birds at Phillip Island can be sexed with an accuracy of 91% using a single measurement of bill depth (>13.33 mm classed as males). Similar analyses at Gibson Steps produced a DF incorporating bill length, bill depth and head length [although the model with the greatest accuracy when applied to birds from Phillip Island (91%) also contained only bill depth]. Published DFs derived in New Zealand had accuracies of 50–85% when applied to birds from Phillip Island and Gibson Steps, supporting earlier suggestions that DFs are not applicable across subspecies of the Little Penguin. In contrast, there was little difference between the accuracy of the DFs in the present study and that previously derived for the same subspecies in Tasmania when applied to birds from Phillip Island (89%) and Gibson Steps (92%). However, as the degree of variation in bill size within a subspecies is unknown it may still be prudent to derive colony-specific DFs.

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Studies examining recruitment processes for soft-sediment macroinvertebrate fauna in intermittent estuaries are rare and most studies of active habitat selection have been tested in the laboratory rather than the field. The present field study examined whether recruitment of the infaunal bivalve Soletellina alba was influenced by water depth and sediment particle size in the intermittent Hopkins River estuary, southern Australia. The number of recruits in sediment trays differed between water depths, but active habitat selection was not evident across treatments of varying sediment particle size. The use of sediments with varying particle sizes also provided an opportunity to identify potential discontinuities in body-size distributions of recruits associated with varying habitat architecture. The length (mm) of recruits was converted to the same scale used to express sediment particle size (i.e. phi units: phi = − log2 of sediment particle size). The size of recruits differed across water depths, but did not differ across treatments with fine (phi = 3) versus coarse (phi = 1) sediment, and no relationships were apparent between bivalve size and sediments consisting of varying particle size. These patterns of recruitment do not correspond with the distribution of adult S. alba within the Hopkins River estuary. Previous sampling has shown that abundances of juvenile and adult S. alba are variable across time, site and water depth, but are often greater at the deeper water depth (1.05 m below the Australian Height Datum). However, recruitment during the present study was greatest at the shallower water depth (0.05 m below AHD), and the apparent absence of active habitat selection suggests that the distribution of adults is unlikely to be attributable to differences in recruitment associated with sediments of varying particle size.

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Microarray plays a major role to identify the over- and under-expressed genes. It is a well-known fact that trace elements in our body play a major role in the metabolic processes of all living organisms. In this paper, the microarray studies related to major trace metals are reviewed. This review forms the basis for the converged effort to locate the genes that are either defective and destabilise the concentration of the trace metals or influenced by the changed concentration of the trace metals that are needed for proper functions of the human body, at different parts of the body.

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The human body was used to illustrate an Autonomic Computing system that possesses self-knowledge, self-configuration, self-optimization, self-healing, and self-protection, knowledge of its environment and user friendliness properties. Autonomic Computing was identified by IBM as one of the Grand Challenges. Many researchers and research groups have responded positively to the challenge by initiating research around one or two of the characteristics
identified by IBM as the requirements for Autonomic Computing. One of the areas that could benefit from the comprehensive approach created by the Autonomic Computing vision is parallel processing on nondedicated clusters. This paper shows a general design of services and initial implementation of a system that moves parallel processing on clusters to the computing mainstream using the Autonomic Computing vision.

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The aim of this paper is to show a general design of autonomic elements and initial implementation of a cluster operating system that moves parallel processing on clusters to the computing mainstream using the autonomic computing vision. The significance of this solution is as follows. Autonomic Computing was identified by IBM as one of computing's Grand Challenges. The human body was used to illustrate an Autonomic Computing system that possesses self-knowledge, self-configuration, self optimization, self-healing, and self-protection, knowledge of its environment and user friendliness properties. One of the areas that could benefit from the comprehensive approach created by the autonomic computing vision is parallel processing on non-dedicated clusters. Many researchers and research groups have responded positively to the challenge by initiating research around one or two of the characteristics identified by IBM as the requirements for autonomic computing. We demonstrate here that it is possible to satisfy all Autonomic Computing characteristics.

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Background: Dietary fatty acids may be associated with diabetes but are difficult to measure accurately.

Objective: We aimed to investigate the associations of fatty acids in plasma and diet with diabetes incidence.

Design: This was a prospective case-cohort study of 3737 adults aged 36-72 y. Fatty acid intake (/kJ) and plasma phospholipid fatty acids (%) were measured at baseline, and diabetes incidence was assessed by self-report 4 y later. Logistic regression excluding (model 1) and including (model 2) body mass index and waist-hip ratio was used to calculate odds ratios (ORs) for plasma phospholipid and dietary fatty acids.

Results: In plasma phospholipid, positive associations with diabetes were seen for stearic acid [OR model 1, highest versus lowest quintile: 4.14 (95% CI: 2.65, 6.49), P for trend < 0.0001] and total saturated fatty acids [OR model 1: 3.76 (2.43, 5.81), P for trend < 0.0001], whereas an inverse association was seen for linoleic acid [OR model 1: 0.22 (0.14, 0.36), P for trend < 0.0001]. Dietary linoleic [OR model 1: 1.77 (1.19, 2.64), P for trend = 0.002], palmitic [OR model 1: 1.65 (1.12, 2.43), P for trend = 0.012], and stearic [OR model 1: 1.46 (1.00, 2.14), P for trend = 0.030] acids were positively associated with diabetes incidence before adjustment for body size. Within each quintile of linoleic acid intake, cases had lower baseline plasma phospholipid linoleic acid proportions than did controls.

Conclusions: Dietary saturated fat intake is inversely associated with diabetes risk. More research is required to determine whether linoleic acid is an appropriate dietary substitute.

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Background and aim
As an evaluation of fatty acid intake measurement, our aim was to examine associations between diet and plasma phospholipid (PL) fatty acids, and whether these were modified by age, sex, country of birth, fasting status, use of cholesterol-lowering medication, body size, chronic disease and other lifestyle factors.

Methods and results
Cross-sectional analysis of plasma PL fatty acid composition and dietary fatty acid intake over 12 months from a 121-item food frequency questionnaire (FFQ) in 4439 men and women aged 40–69 years, born in Australia, Greece or Italy. Crude correlation coefficients ranged from 0.18 to 0.40; and corrected correlation coefficients from 0.38 to 0.78 for total monounsaturated, polyunsaturated, n-6, n-3 fatty acids, oleic acid, linoleic acid, EPA and DHA. Weaker associations were observed for other fatty acids. The associations did not vary significantly by fasting status, use of lipid lowering medication or alcohol intake, but for some fatty acids did vary by sex, age, body mass index, country of birth, smoking and previous heart attack or diabetes.

Conclusions
The FFQ provides useful information on intakes of mono- and polyunsaturated fatty acids. Correlations did not differ by fasting status, or use of lipid-lowering medication.

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Aims To estimate the level of under-reporting of energy intake by gender, age, ethnicity and body size (normal, overweight, obese) in the 1997 National Nutrition Survey (NNS97) in New Zealand.
Methods Data were from 4,258 participants (1,808 men and 2,450 women aged 15 years and over) who completed the 24-hour diet recall; the primary methodology used in the NNS97. Under-reporting was assessed using the ratio of reported energy intake to estimated resting metabolic rate (EI: RMRest). Cut-off limits were used to identify percentages of under-reporters in the various subgroups.
Results Mean EI: RMRest was 1.40 for all participants (1.51 for men, 1.30 for women, p<0.001) with older age being associated with lower EI: RMRest (p<0.001). There were no significant differences in mean EI: RMRest between ethnic groups for men.
Mean EI: RMRest for women were: Maori 1.46, European 1.29, and Pacific 1.37 (p<0.01). A larger body size was associated with a significantly lower EI: RMRest especially for women.
Percentages of ‘definite’ under-reporters (individual EI: RMRest <0.9) were as follows: men 12%, women 21%; Europeans 16%, Maori 23% and Pacific 26%; normal weight (11%), overweight (19%) and obese (27%) participants; and from 10% in the youngest to 23% in the oldest age group (p<0.001 for all results).
Conclusion In this study, in agreement with the literature, women, older people and obese people under-reported more than men, younger people and non-obese people. Possible ethnic differences in under-reporting rates need further study. Care is needed in interpreting the energy intake data from the NNS97.

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In Little Penguins Eudyptula minor there are no reliable plumage or body size differences that can be used visually to distinguish the sex of individuals. However, sexual dimorphism of morphometric measures has been noted, with males always being a little larger than females. In this study, differences between E. minor sexes at eight colonies in south-eastern Australia were determined statistically via discriminant function analysis (DFA) and through the utilization of DNA-based techniques developed for non-ratite birds. The DFA correctly determined gender in 91.1% of cases and molecular methods were 100% accurate. Our DFA success rate of classification is similar to that previously published for Little Penguins in Victoria. In this study statistically significant differences in mean bill depths and lengths were found between Little Penguin colonies at St Kilda, Phillip Island and Gabo Island, compared to colonies at Kangaroo Island, Granite Island, Middle Island and London Bridge. As birds in eastern populations (St Kilda, Phillip Island, Gabo Island) exhibit statistically significantly smaller beaks (bill depth and bill length), separate discriminant functions were investigated for each phenotypically distinct geo-spatial cohort. Interestingly, cluster analysis for bill length identified three groups: western (Kangaroo Island and Granite Island), eastern (St Kilda, Phillip Island and Middle Island) and the London Bridge Little Penguin colony, which constituted a separate group. We conclude that while there is a slight increase in DF power for colonies west of Cape Otway and for some specific colonies, colony-specific DFA is not required to identify the sex of Little Penguins in south-eastern Australia.