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Distribution by Scientific Domains

Life Sciences	27%
Medical Sciences	22%
Chemistry	22%
Earth and Environmental Science	6%
Psychology	4%
Engineering	4%
6 Other Domains	15%

Distribution within Life Sciences

Ornithology	14%
Entomology	11%

Selected Abstracts

Foraging Behaviour of Subordinate Great Tits (Parus major).

ETHOLOGY, Issue 10 2001
Can Morphology Reduce the Cost of Subordination?
This paper studies the magnitude of the behavioural shift, from forage standing to forage hanging, of subordinate great tits (Parus major) in two different social contexts: feeding solitarily vs. feeding with a dominant conspecific. The aim is to test the hypothesis that differences in morphological design provide subordinates with varying abilities to reduce the presumed costs of subordination. We find that different subordinate individuals change the foraging behaviour, occupying a different niche when an intra-specific competitor is present. Morphology linked to sexual dimorphism, specifically body mass, is the factor responsible for the different magnitudes of change. Lighter subordinates can remain longer than heavier ones at the feeding patch without interrupting their foraging. Thereby, the former reduce the costs of being subordinate more than the latter. Among subordinates, females are lighter than males; they also spend more time feeding in the presence of a dominant conspecific than males do. No differences are found between age categories. We find no relationship between tarsus length and individual ecological plasticity. Our results support the idea that the ecological plasticity due to morphological differences is a mechanism that allows subordinate individuals to overcome costs associated with subordination. [source]

Towards a New Art Curriculum: Reflections on Pot Fillers and Fire Lighters

INTERNATIONAL JOURNAL OF ART & DESIGN EDUCATION, Issue 1 2000
Gordon Bell
This contribution is derived from an address presented to the NSEAD Annual Conference (1999),Towards a New Arts Education' in association with Bretton Hall, a specialist institution for the arts and education, to mark the 50th anniversary of its Foundation in September 1949. [1] An analysis of the role of art and design education is set in the context of an arts related curriculum and the case for an interdependent, teachable and accessible programme is outlined. Proposals for the maintenance and development of a future for arts education is tested against certain key questions and a theory of ,good teaching' in the arts [source]

Eating problems at age 6 years in a whole population sample of extremely preterm children

DEVELOPMENTAL MEDICINE & CHILD NEUROLOGY, Issue 2 2010
MUTHANNA SAMARA
Aim, The aim of this study was to investigate the prevalence of eating problems and their association with neurological and behavioural disabilities and growth among children born extremely preterm (EPC) at age 6 years. Method, A standard questionnaire about eating was completed by parents of 223 children (125 males [56.1%], 98 females [43.9%]) aged 6 years who were born at 25 weeks' gestation or earlier (mean 24.5wks, SD 0.7wks; mean birthweight 749.1g, SD 116.8g), and parents of 148 classmates born at term (66 males [44.6%], 82 females [55.4%]). All children underwent neurological, cognitive, and anthropometric assessment, and parents and teachers completed a behaviour scale. Results, Eating problems were more common among the EPC than the comparison group (odds ratio [OR] 3.6, 95% confidence interval [CI] 2.1,6.3), including oral motor (OR 5.2, 95% CI 2.8,9.9), hypersensitivity (OR 3.0, 95% CI 1.6,5.6), and behavioural (OR 3.8, 95% CI 1.9,7.6) problems. Group differences were reduced after adjustment for cognitive impairment, neuromotor disability, and other behaviour problems. EPC with eating problems were shorter, lighter, and had lower mid-arm circumference and lower body mass index (BMI) even after adjusting for disabilities, gestational age, birthweight, and feeding problems at 30 months. Interpretation, Eating problems are still frequent in EPC at school age. They are only partly related to other disabilities but make an additional contribution to continued growth failure and may require early recognition and intervention. [source]

Trade-offs in oviposition choice?

ENTOMOLOGIA EXPERIMENTALIS ET APPLICATA, Issue 2 2007
Food-dependent performance, defence against predators of a herbivorous sawfly
Abstract The sawfly Athalia rosae L. (Hymenoptera: Tenthredinidae) is a feeding specialist on plant species of the Brassicaceae, which are characterised by secondary metabolites, called glucosinolates. The larvae can take up the respective glucosinolates of their hosts and concentrate them in their haemolymph to protect themselves against predators. Oviposition preferences of naïve females were tested for three species, Sinapis alba L., Brassica nigra (L.) Koch, and Barbarea stricta Andrz., and were related to larval performance patterns. Larvae were reared on either one of these plants and it was investigated how host-plant quality influences both the developmental times and growth of larvae (bottom-up) and the defence efficiency against predators (top-down). Innately, almost all adult females avoided B. stricta for oviposition and clearly preferred B. nigra over S. alba. On average, larvae developed best on B. nigra. Female larvae reached similar final body masses on all host-plant species, but males reared on S. alba were slightly lighter. The developmental time of larvae reared on B. stricta was significantly longer than on the other two plants. However, larvae reared on B. stricta were best protected against the predatory wasp Polistes dominulus Christ (Hymenoptera: Vespidae). The wasps rejected these larvae most often, while they attacked larvae reared on S. alba most frequently. Thus, larvae feeding on B. stricta theoretically run a higher risk of predation due to a prolonged developmental time, but in practice they are better protected against predators. Overall, oviposition preferences of A. rosae seem to be more influenced by bottom-up effects on larval performance than by top-down effects. [source]

Developmental toxicity of in ovo exposure to polychlorinated biphenyls: I. Immediate and subsequent effects on first-generation nestling American kestrels (Falco sparverius)

ENVIRONMENTAL TOXICOLOGY & CHEMISTRY, Issue 3 2003
Kim Fernie
Abstract We determined that in ovo exposure to polychlorinated biphenyls (PCBs) alters growth off first-generation nestlings during and one year after parental exposure. Captive American kestrels (Falco sparverius) laid eggs with environmentally relevant total PCB levels (34.1 ,g/g whole-egg wet wt) when fed PCB-spiked (Aroclor® 1248, 1254, and 1260) food (7 mg/kg body wt/d) for 100 d in 1998. In 1999, the same adults laid eggs with estimated total PCBs of 29.0 ,g/g. Nonsurviving PCB-exposed chicks were small (mass, bones) in 1998. Survivors showed a strong sex-specific growth response (mass, bones) compared to respective sex controls: Only female hatchlings were larger, and only male nestlings had longer feathers (1998); maximal growth and bone growth rates also differed (males were advanced, faster; females delayed, slower) (1999); and male nestlings fledged earlier and were smaller, while females were larger (1998, 1999). However, regardless of sex, PCB-exposed nestlings generally grew at faster rates in both years. In 1998, greater contaminant burdens and toxic equivalent concentrations in sibling eggs were associated with nestlings being lighter, having longer bones and feathers, and growing at faster rates (mass, bone) for females but slower rates (mass) for males. Both physiological-biochemical and behavioral changes are likely mechanisms. This study supports and expands on the Great Lakes embryo mortality, edema, and deformities syndrome: While PCB exposure alters nestling size, maximal growth and growth rates also change immediately, are sustained, and are sex specific. [source]

Generalized Birnbaum-Saunders distributions applied to air pollutant concentration

ENVIRONMETRICS, Issue 3 2008
Víctor Leiva
Abstract The generalized Birnbaum-Saunders (GBS) distribution is a new class of positively skewed models with lighter and heavier tails than the traditional Birnbaum-Saunders (BS) distribution, which is largely applied to study lifetimes. However, the theoretical argument and the interesting properties of the GBS model have made its application possible beyond the lifetime analysis. The aim of this paper is to present the GBS distribution as a useful model for describing pollution data and deriving its positive and negative moments. Based on these moments, we develop estimation and goodness-of-fit methods. Also, some properties of the proposed estimators useful for developing asymptotic inference are presented. Finally, an application with real data from Environmental Sciences is given to illustrate the methodology developed. This example shows that the empirical fit of the GBS distribution to the data is very good. Thus, the GBS model is appropriate for describing air pollutant concentration data, which produces better results than the lognormal model when the administrative target is determined for abating air pollution. Copyright © 2007 John Wiley & Sons, Ltd. [source]

Foraging Behaviour of Subordinate Great Tits (Parus major).

Patterns of calcium-binding proteins support parallel and hierarchical organization of human auditory areas

EUROPEAN JOURNAL OF NEUROSCIENCE, Issue 2 2003
Oriana Chiry
Abstract The human primary auditory cortex (AI) is surrounded by several other auditory areas, which can be identified by cyto-, myelo- and chemoarchitectonic criteria. We report here on the pattern of calcium-binding protein immunoreactivity within these areas. The supratemporal regions of four normal human brains (eight hemispheres) were processed histologically, and serial sections were stained for parvalbumin, calretinin or calbindin. Each calcium-binding protein yielded a specific pattern of labelling, which differed between auditory areas. In AI, defined as area TC [see C. von Economo and L. Horn (1930) Z. Ges. Neurol. Psychiatr.,130, 678,757], parvalbumin labelling was dark in layer IV; several parvalbumin-positive multipolar neurons were distributed in layers III and IV. Calbindin yielded dark labelling in layers I,III and V; it revealed numerous multipolar and pyramidal neurons in layers II and III. Calretinin labelling was lighter than that of parvalbumin or calbindin in AI; calretinin-positive bipolar and bitufted neurons were present in supragranular layers. In non-primary auditory areas, the intensity of labelling tended to become progressively lighter while moving away from AI, with qualitative differences between the cytoarchitectonically defined areas. In analogy to non-human primates, our results suggest differences in intrinsic organization between auditory areas that are compatible with parallel and hierarchical processing of auditory information. [source]

Biocompatibility of Lotus-type Stainless Steel and Titanium in Alveolar Bone

ADVANCED ENGINEERING MATERIALS, Issue 9 2006
Y. Higuchi
Abstract Lotus-type porous stainless steel (SUS304L) and porous titanium were fabricated by unidirectional solidification in a mixture gas of hydrogen and argon. The porous metals which were cut into 5,mm cubes (non-dehydrogenated) and 3.4,mm,,×,5,mm cylinders (dehydrogenated) were implanted into the canine mandible alveolar bone for two, four and eight weeks for animal experiments. The changes in the tissues were observed using SEM. For porous stainless steel (cylindrical; dehydrogenated) new formation of bones was observed around the sample in two weeks without any sign of bony ingrowth into the pores. The osteogenesis was found in shallow areas in the pores in four weeks and deep in the pores in eight weeks. Porous titanium, on the other hand, showed deep ingrowth of new bones in four weeks. Our observations allowed us to expect application of the porous metals as biomaterials. They maintain mechanical strength and are lighter in weight so that it is expected to be applied for dental implants and core materials of artificial bones. [source]

Study of Five Discrete-Interval-Type Ground Water Sampling Devices

GROUND WATER MONITORING & REMEDIATION, Issue 3 2004
Louise V. Parker
Five relatively newly developed discrete-interval-type ground water sampling devices,the KABIS, HydraSleeve, Discrete Interval, Pneumo-Bailer, and USGS passive diffusion bag (PDB) samplers,were tested to determine their ability to recover representative concentrations of a variety of analytes,volatile organics, explosives, pesticides, and metals,from a standpipe and trichloroethylene (TCE) from a deep monitoring well. Samples taken from a well were compared with samples taken using low-flow sampling. The PDB sampler was the easiest to use, but could only be used to sample volatile organic compounds (VOCs). The HydraSleeve and the KABIS samplers were also easy to use; these devices produced representative concentrations of explosives, pesticides, and metals in the standpipe experiments, but elevated the turbidity in our monitoring well. Although there were statistically significant differences for some VOCs with both devices, these differences were generally very small (< 5%). The one exception was an 18% loss of TCE with the KABIS sampler. The Discrete Interval sampler and the Pneumo-Bailer are pressurized devices that are designed to only collect a sample when activated. The Pneumo-Bailer was heavy and awkward to handle, required a nitrogen tank in the field, and involved many steps to operate. The Discrete Interval sampler only required a bicycle pump to pressurize the chamber and was lighter and easier to handle and operate than its counterpart. Both devices generally delivered representative concentrations of all the analytes tested. [source]

Breeding biology of the White-rumped Swallow Tachycineta leucorrhoa in Buenos Aires Province, Argentina

IBIS, Issue 1 2007
VIVIANA MASSONI
We conducted a study of the breeding biology of the White-rumped Swallow Tachycineta leucorrhoa nesting in nestboxes in a flat, farming landscape in Buenos Aires Province, Argentina. White-rumped Swallow nesting attempts were detected from the end of September to mid December, with most clutches laid during October. Birds laid clutches of 4,6 eggs with a mode of five eggs; most broods hatched synchronously (58%), but hatching spread could last up to 4 days. Nestling growth curves adjust well to logistic functions, and at day 15 nestlings attain the asymptotic weight of 21.6 g. Clutch size in White-rumped Swallows declined significantly as the season progressed. In addition, late-season eggs were smaller and late-season nestlings had a shorter nestling period and lower weight at day 15, probably leaving the nest lighter than early-season nestlings. These data suggest that the Swallows would benefit greatly from laying early in the season, which would provide nestlings with better survival prospects. However, both major sources of nest mortality, interspecific competition for nest-sites and nestling mortality during bad weather, decreased through the season. White-rumped Swallows follow the pattern found for other southern species, as it has smaller clutch size, lower growth rate and remains longer at the nest than its Northern Hemisphere congener the Tree Swallow Tachycineta bicolor. [source]

Body protein does not vary despite seasonal changes in fat in the White Stork Ciconia ciconia

IBIS, Issue 1 2002
Delphine Michard-Picamelot
To understand how a large soaring bird, the White Stork Ciconia ciconia, copes with energy constraints, we compared changes in body mass in 14 captive adult storks with the body composition of 12 free-ranging adult storks found dead from accidents. The captive storks, already in an enclosure for several years, were fed ad libitum. They were weighed daily for 1.5,3.5 years using an automatic device. The bodies of the accidentally killed storks were analysed to determine total water, lipid, protein and ash contents, and to assess the biochemical composition of certain organs. Females were on average 20% lighter and 24% smaller than males, but the body mass of the sexes varied in parallel throughout the year. Body mass peaked in December and January (25,30% above minimal body mass), due essentially to large fat stores in subcutaneous and abdominal adipose tissues. Body mass and body lipid rapidly decreased from February to June, whether the storks reared chicks successfully or not, and remained minimal for a few days into July. In contrast to birds using flapping flight, no variation in body protein or pectoral muscle protein was observed while breeding, even though the moult occurred then, nor in August, before the time when wild storks migrate. An endogenous regulation of body fuels is discussed. [source]

Instabilities during batch sedimentation in geometries containing obstacles: A numerical and experimental study,

INTERNATIONAL JOURNAL FOR NUMERICAL METHODS IN FLUIDS, Issue 8 2007
Rekha R. Rao
Abstract Batch sedimentation of non-colloidal particle suspensions is studied with nuclear magnetic resonance flow visualization and continuum-level numerical modelling of particle migration. The experimental method gives particle volume fraction as a function of time and position, which then provides validation data for the numerical model. A finite element method is used to discretize the equations of motion, including an evolution equation for the particle volume fraction and a generalized Newtonian viscosity dependent on local particle concentration. The diffusive-flux equation is based on the Phillips model (Phys. Fluids A 1992; 4:30,40) and includes sedimentation terms described by Zhang and Acrivos (Int. J. Multiphase Flow 1994; 20:579,591). The model and experiments are utilized in three distinct geometries with particles that are heavier and lighter than the suspending fluid, depending on the experiment: (1) sedimentation in a cylinder with a contraction; (2) particle flotation in a horizontal cylinder with a horizontal rod; and (3) flotation around a rectangular inclusion. Secondary flows appear in both the experiments and the simulations when a region of higher density fluid is above a lower density fluid. The secondary flows result in particle inhomogeneities, Rayleigh,Taylor-like instabilities, and remixing, though the effect in the simulations is more pronounced than in the experiments. Published in 2007 by John Wiley & Sons, Ltd. [source]

Colour improvement of common carp (Cyprinus carpio) fillets by hydrogen peroxide for surimi production

INTERNATIONAL JOURNAL OF FOOD SCIENCE & TECHNOLOGY, Issue 9 2008
Ali Jafarpour
Summary The preferred colour for surimi is white, but surimi prepared from light fillets of common carp (Cyprinus carpio) is slightly pink. Hydrogen peroxide (H2O2; 1,3% v/v) with and without sodium tri-polyphosphate (STP; 1,2% w/v) was added to a sodium carbonate bath (pH 7.0,11.5) resulting in a final pH range of 4.4,10.1 which was injected into carp fillets. After soaking and tumbling for 30 min at 4,10 °C, the fillets were evaluated for colour and water holding capacity (WHC). Fillets tumbled with treatment solution with different pH levels (7.0,11.5), but with no H2O2 or STP added, had improved colour with significantly (P < 0.05) higher L* compared with untreated fillets as the control. However, the colour improvement [(L* and colour deviation (,E)] was not significantly different (P > 0.05) within the pH levels (7.0,11.5) trialled. With increasing H2O2 levels (1,3%), fillets became lighter and ,E increased significantly (P < 0.05), especially with a 3% H2O2 treatment at pH of 10.5 (adjusted pH before H2O2 addition, actual pH after H2O2 addition was 8.2). The whiteness (L*,3b*) of kamaboko produced from treated (3% H2O2, pH 10.5) common carp light fillets was not significantly different to that of kamaboko from Alaska pollock and threadfin bream. Treatments combining H2O2 (3%) with STP (1,2%) significantly reduced the L* value obtained in comparison with fillets treated with only H2O2 (3%). Similarly, fillets treated with STP (1%) alone, resulting in lower L* values, irrespective of treatment pH (7.0,11.5). WHC, an indicator of the quality of the fillet texture, increased from 816 g/kg at pH 7.0 without STP to 841 g/kg at pH 11.5 with 1% STP. Treatment with H2O2 (without STP) decreased the WHC of the fillets. [source]

The sensitive hare: sublethal effects of predator stress on reproduction in snowshoe hares

JOURNAL OF ANIMAL ECOLOGY, Issue 6 2009
Michael J. Sheriff
Summary 1.,Prey responses to high predation risk can be morphological or behavioural and ultimately come at the cost of survival, growth, body condition, or reproduction. These sub-lethal predator effects have been shown to be mediated by physiological stress. We tested the hypothesis that elevated glucocorticoid concentrations directly cause a decline in reproduction in individual free-ranging female snowshoe hares, Lepus americanus. We measured the cortisol concentration from each dam (using a faecal analysis enzyme immunoassay) and her reproductive output (litter size, offspring birth mass, offspring right hind foot (RHF) length) 30 h after birth. 2.,In a natural monitoring study, we monitored hares during the first and second litter from the population peak (2006) to the second year of the decline (2008). We found that faecal cortisol metabolite (FCM) concentration in dams decreased 52% from the first to the second litter. From the first to the second litter, litter size increased 122%, offspring body mass increased 130%, and offspring RHF length increased 112%. Dam FCM concentrations were inversely related to litter size (r2 = 0·19), to offspring birth mass (r2 = 0·32), and to offspring RHF length (r2 = 0·64). 3.,In an experimental manipulation, we assigned wild-caught, pregnant hares to a control and a stressed group and held them in pens. Hares in the stressed group were exposed to a dog 1,2 min every other day before parturition to simulate high predation risk. At parturition, unsuccessful-stressed dams (those that failed to give birth to live young) and stressed dams had 837% and 214%, respectively, higher FCM concentrations than control dams. Of those females that gave birth, litter size was similar between control and stressed dams. However, offspring from stressed dams were 37% lighter and 16% smaller than offspring from control dams. Increasing FCM concentration in dams caused the decline of offspring body mass (r2 = 0·57) and RHF (r2 = 0·52). 4.,This is the first study in a free-ranging population of mammals to show that elevated, predator-induced, glucocorticoid concentrations in individual dams caused a decline in their reproductive output measured both by number and quality of offspring. Thus, we provide evidence that any stressor, not just predation, which increases glucocorticoid concentrations will result in a decrease in reproductive output. [source]

Influence of maternal mass and condition on energy transfer in Weddell seals

JOURNAL OF ANIMAL ECOLOGY, Issue 3 2006
KATHRYN E. WHEATLEY
Summary 1Environmental variation influences food abundance and availability, which is reflected in the reproductive success of top predators. We examined maternal expenditure, offspring mass and condition for Weddell seals in 2 years when individuals exhibited marked differences in these traits. 2For females weighing 355 kg there was a positive relationship between maternal post-partum mass (MPPM) and lactation length, but below this there was no relationship, suggesting that heavier females were able to increase lactation length but lighter females were restricted to a minimum lactation period of 33 days. 3Overall, females were heavier in 2002, but in 2003 shorter females were lighter than similar-sized females in 2002 suggesting that the effects of environmental variability on foraging success and condition are more pronounced in smaller individuals. 4There was no relationship between MPPM and pup birth mass, indicating pre-partum investment did not differ between years. However, there was a positive relationship between MPPM and pup mass gain. Mass and energy transfer efficiency were 10·2 and 5·4% higher in 2002 than 2003, which suggests costs associated with a putatively poor-resource year were delayed until lactation. 5Heavier females lost a higher proportion of mass during lactation in both years, so smaller females may not have been able to provide more to their offspring to wean a pup of similar size to larger females. 6MPPM had only a small influence on total body lipid; therefore, regardless of mass, females had the same relative body composition. Females with male pups lost a higher percentage of lipid than those with female pups, but by the end of lactation female pups had 4·5% higher lipid content than males. 7It appears that for Weddell seals the consequences of environmentally induced variation in food availability are manifested in differences in maternal mass and expenditure during lactation. These differences translate to changes in pup mass and condition at weaning with potential consequences for future survival and recruitment. [source]

Climate and population density induce long-term cohort variation in a northern ungulate

JOURNAL OF ANIMAL ECOLOGY, Issue 5 2001
Mads C. Forchhammer
Summary 1,Density-dependent and climatic conditions experienced by individuals before and after birth differ considerably between cohorts. Such early environmental variability has the potential to create persistent fitness differences among cohorts. Here we test the hypothesis that conditions experienced by individuals in their early development will have long-term effects on their life history traits. 2,We approached this by analysing and contrasting the effects of climate (the North Atlantic Oscillation, NAO) and population density at year of birth on cohort birth weight, birth date, litter size, age of maturity, survival and fecundity of Soay sheep, Ovies aries L., ewes in the population on the island of Hirta, St Kilda, Scotland. 3,Significant intercohort variations were found in life history traits. Cohorts born after warm, wet and windy (high NAO) winters were lighter at birth, born earlier, less likely to have a twin and matured later than cohorts born following cold and dry (low NAO) winters. High population densities in the winter preceding birth also had a negative effect on birth weight, birth date and litter size, whereas high postnatal densities delayed age of first reproduction. 4,High NAO winters preceding birth depressed juvenile survival but increased adult survival and fecundity. The negative influence of high NAO winters on juvenile survival is likely to be related to mothers' compromised physical condition while the cohort is in utero, whereas the positive influence on adult survival and fecundity may relate to the improved postnatal forage conditions following high NAO winters. High pre- and postnatal population densities decreased juvenile (neonatal, yearling) and adult (2,4 years) survivorship but had no significant effect fecundity. [source]

Impacts of sudden winter habitat loss on the body condition and survival of redshank Tringa totanus

JOURNAL OF APPLIED ECOLOGY, Issue 3 2006
NIALL H. K. BURTON
Summary 1Recent theoretical modelling has provided important insights into how habitat loss may affect local populations through impacts on individual fitness (survival, body condition, fecundity). Despite this, attempts to provide empirical evidence of such impacts on displaced individuals have been limited. Using a before-after-control-impact (BACI) approach, we report how a sudden loss of wintering habitat impacted on the body condition and survival of redshank Tringa totanus. 2The intertidal mudflats of Cardiff Bay, UK, were inundated with freshwater in November 1999 following impoundment by a barrage, resulting in the displacement of c. 300 redshank to adjacent habitat on the Severn Estuary. Movements and the survival of these birds were monitored through observations of colour-marked individuals. Comparative survival rates were calculated for marked populations at the main recipient site, Rhymney, and a control site. 3Displaced redshank had difficulty maintaining their mass in the first winter post-barrage closure: adults previously only recorded at Cardiff Bay were significantly lighter than those previously recorded at Rhymney. 4Survival rates of displaced redshank also declined. The estimated annual survival of adult Cardiff Bay redshank fell from 0·846 in the 2 years pre-barrage closure to 0·778 in the 3 following years because of a significant decline in winter survival (P = 0·0006). In comparison, there was no significant change in the survival of adult Rhymney redshank, and adult survival at the control site was actually greater post-barrage closure than beforehand. The lack of decline in these rates and the similarity between those of Cardiff Bay adults pre-barrage closure and Rhymney adults indicate that the increase in winter mortality of Cardiff Bay birds resulted from their displacement. 5Synthesis and applications. This study provides the first conclusive empirical evidence that habitat loss can impact individual fitness in a bird population. Adult redshank displaced from Cardiff Bay experienced poor body condition and a 44% increase in mortality rate. Without an increase in the recruitment of first-winter birds, such a change is likely to reduce substantially local population size. The results reported here should help to inform governments, planners and non-governmental organizations (NGOs) seeking to understand how developments might impact on animal populations. [source]

Perceptions of and Preferences for Skin Color, Black Racial Identity, and Self-Esteem Among African Americans,

JOURNAL OF APPLIED SOCIAL PSYCHOLOGY, Issue 11 2001
Stephanie Irby Coard
The purpose of the present study was to examine the role of skin color (i.e., lightness,darkness), as it pertains to racial identity development theory and self-esteem among 113 African American college students of various skin colors. Findings revealed that the sample preferred skin color of a medium tone, rather than exhibiting self-preference for either lighter or darker skin tones. There was also a significant relationship between one's perceptions of and preferences for his or her skin color and the skin tones idealized by others (e.g., opposite gender, family). Lighter skin color was positively related to higher levels of racial identity attitudes (immersion/emersion); the more satisfied darker skinned individuals were with their skin color, the lower their self-esteem, and gender differences existed in perceptions of others' preferences for skin color. Implications of this study for providing therapeutic clinical services and fostering the healthy psychological development of African American men, women, and children are discussed. [source]

Seasonal, sexual and developmental differences in hoopoe Upupa epops preen gland morphology and secretions: evidence for a role of bacteria

JOURNAL OF AVIAN BIOLOGY, Issue 2 2009
Manuel Martín-Vivaldi
The uropygial glands of birds serve multiple functions, and there is great interspecific variability in the composition and properties of their secretions. A special case is the secretion in the hoopoes Upupa epops, and green woodhoopoes Phoeniculus purpureus, which, contrary to the commonly white and odourless secretions, are dark with pungent odour. Recently, bacteria have been isolated from glands of both woodhoopoes and hoopoes and here we test the hypothesis that bacteria are responsible of some of the special properties of glands and secretions of this group of birds. We explore natural seasonal changes and intersexual differences in the properties of hoopoe glands and secretions, check the natural occurrence of bacteria within secretions, and analyse the effect of experimental injection of antibiotics on uropygial gland properties. Male glands underwent no seasonal changes, and their secretions were invariably white and odourless, very similar to female glands outside the breeding season. However, in comparison to the uropygial gland of non-breeding females, those of incubating females showed a marked increase in size and volume of secretion produced, which became dark and pungent. All these parameters increased until the hatching date and returned to values similar to those in the prelaying phase towards the end of the nestling period. Nestling glands produced secretions similar to those of females in colour and odour. Gland size of both females and nestlings predicted the amount of secretion produced. Microscopic techniques confirmed the presence of bacteria at high density and in active division in all dark secretions examined. The antibiotic treatment significantly reduced the load of enterococci in nestling glands, did not affect size of glands, but diminished the volume of secretion, which was lighter in colour than that of control nestlings. In nesting females, the experimental injection of antibiotic affected some measurements of gland size and secretion colour. Because the experiment did not affect general health estimates (immunocompetence, body condition or growing) of nestlings, our results suggest that some of the special properties of hoopoe glands are mediated by the presence of symbiotic bacteria. [source]

Construction of the Femoral Neck During Growth Determines Its Strength in Old Age,

JOURNAL OF BONE AND MINERAL RESEARCH, Issue 7 2007
Roger M D Zebaze
Abstract Study of the design of the FN in vivo in 697 women and in vitro in 200 cross-sections of different sizes and shapes along each of 13 FN specimens revealed that strength in old age was largely achieved during growth by differences in the distribution rather than the amount of bone material in a given FN cross-section from individual to individual. Introduction: We studied the design of the femoral neck (FN) to gain insight into the structural basis of FN strength in adulthood and FN fragility in old age. Materials and Methods: Studies in vivo were performed using densitometry in 697 women and in vitro using high-resolution ,CT and direct measurements in 13 pairs of postmortem specimens. Results: The contradictory needs of strength for loading yet lightness for mobility were met by varying FN size, shape, spatial distribution, and proportions of its trabecular and cortical bone in a cross-section, not its mass. Wider and narrower FNs were constructed with similar amounts of bone material. Wider FNs were relatively lighter: a 1 SD higher FN volume had a 0.67 (95% CI, 0.61,0.72) SD lower volumetric BMD (vBMD). A 1 SD increment in height was achieved by increasing FN volume by 0.32 (95% CI, 0.25,0.39) SD with only 0.15 (95% CI, 0.08,0.22) SD more bone, so taller individuals had a relatively lighter FN (vBMD was 0.13 [95% CI, 0.05,0.20 SD] SD lower). Greater periosteal apposition constructing a wider FN was offset by even greater endocortical resorption so that the same net amount of bone was distributed as a thinner cortex further from the neutral axis, increasing resistance to bending and lowering vBMD. This was recapitulated at each point along the FN; varying absolute and relative degrees of periosteal apposition and endocortical resorption focally used the same amount of material to fashion an elliptical FN of mainly cortical bone near the femoral shaft to offset bending but a more circular FN of proportionally more trabecular and less cortical bone to accommodate compressive loads adjacent to the pelvis. This structural heterogeneity was largely achieved by adaptive modeling and remodeling during growth,most of the variance in FN volume, BMC, and vBMD was growth related. Conclusions: Altering structural design while minimizing mass achieves FN strength and lightness. Bone fragility may be the result of failure to adapt bone's architecture to loading, not just low bone mass. [source]

Morphometry and composition of aragonite and vaterite otoliths of deformed laboratory reared juvenile herring from two populations

JOURNAL OF FISH BIOLOGY, Issue 6 2003
J. Tomás
Vaterite otoliths were sampled from two reared populations (Celtic and Clyde Seas) of juvenile herring Clupea harengus. The crystallography, elemental composition and morphometry were analysed and compared with those of normal aragonite otoliths. The incidence of vaterite otoliths in the juveniles sampled (n = 601) ranged from 7·8% in the Clyde population to 13·9% in the Celtic Sea population, and was 5·5% in the small sample (n = 36) of wild adults examined. In all but one case fish had only one vaterite otolith; the corresponding otolith of the pair was completely aragonite. Although the majority of the juveniles sampled showed craniofacial deformities, there was no link between the skull or jaw malformation and the incidence of vaterite otoliths. All vaterite otoliths had an aragonite inner area, and vaterite deposition began sometime after the age of 90 days. The vaterite otoliths were larger and lighter than their corresponding aragonite partners, and were less dense as a consequence of the vaterite crystal structure. The vaterite areas of the otoliths were depleted in Sr, Na and K. Concentrations of Mn were higher in the vaterite areas. The transition between the aragonite inner areas and the vaterite areas was sharply delineated. Within a small spatial scale (20 ,m3) in the vaterite areas, however, there was co-precipitation of both vaterite and aragonite. The composition of the aragonite cores in the vaterite otoliths was the same as in the cores of the normal aragonite otoliths indicating that the composition of the aragonite cores did not seed the shift to vaterite. Vaterite is less dense than aragonite, yet the concentrations of Ca analysed with wavelength-dispersive spectrometry (WDS) were the same between the two polymorphs, indicating that Ca concentrations measured with WDS are not a good indicator of hypermineralized zones with high mineral density. The asymmetry in density and size of the otoliths may cause disruptions of hearing and pressure sensitivity for individual fish with one vaterite otolith, however, the presence of vaterite otoliths did not seem to affect the growth of these laboratory reared juvenile herring. [source]

BAKING PROPERTIES OF MILK PROTEIN-COATED WHEAT BRAN,

JOURNAL OF FOOD PROCESSING AND PRESERVATION, Issue 1 2008
CHARLES I. ONWULATA
ABSTRACT Increasing the dietary fiber content of formulated foods will benefit the health and nutrition of consumers. The problem is that it is difficult to add substantial amounts of dietary fiber to formulated foods. Fiber absorbs significant amounts of water from surrounding ingredients creating texture problems such as soggy and dry patches in the foods. In this study, red wheat bran milled and sieved smaller than 140 microns was coated by spraying with a 50/50 emulsion of whey protein isolates (WPIs) and casein. WPI and casein emulsion was produced first by blending and shearing the milk proteins in ice and water and then evaporating under partial vacuum for 75 min at 45C. Cookies and muffins made with the milk protein-coated red wheat (MPCF) bran and the noncoated wheat bran (NCF), replacing 5, 10 and 15 wt % of the flour, were compared to control cookies and muffins made without added fiber. The water-holding capacity (WHC) of the MPCF and NCF was determined along with their moisture, color, hardness, and volume in the baked cookies and muffins. There was a significant (P < 0.01) improvement (250%) in loss of WHC of MPCF over NCF. In cookies, MPCF absorbed significantly less water and was slightly darker at 5 wt % substitution than NCF, but was between 12 to 60% higher in baked volume than the control. MPCF muffins were lighter in color and harder except for the 5 wt % muffins that were softer and higher in percent baked volume. Adding up to 15-g MPCF per 100 g batter can be added to baked cookies and muffins to increase fiber content and improve WHC and volume. PRACTICAL APPLICATIONS This study determined that coating wheat bran with specially treated dairy proteins reduced the amount of water the bran can absorb when added up to 15 wt% to formulations, or in the finished products, helping to maintain textural integrity of products. The intact wheat bran remains available for its functional health enhancing roles when consumed and digested. This knowledge allows the creation of nutritious high-fiber products with desirable texture. [source]

EFFECT OF ERYTHRITOL ON QUALITY CHARACTERISTICS OF REDUCED-CALORIE DANISH COOKIES

JOURNAL OF FOOD QUALITY, Issue 2010
SHENG-DUN LIN
ABSTRACT The effects of erythritol on the quality characteristics of Danish cookies were studied. Danish cookies were formulated using erythritol as a sweetener to replace 0, 25, 50, 75 and 100% sucrose. The results showed that Hunter L -values and erythritol contents of cookies increased with increasing erythritol level whereas there was no difference in the moisture, protein, fat, ash and hardness of cookies prepared with sucrose or erythritol. The erythritol was stable during baking. In descriptive analysis, the surface color of cookies became lighter, and the sweetness of cookies became less sweet as erythritol level increased and sucrose decreased. The 50, 75 and 100% erythritol cookies had a cooling sensation. The moistness and hardness of cookies showed no difference among all samples. In hedonic test, the degree of surface color, sweetness, hardness, flavor and overall liking of cookies prepared with 0, 25 and 50% replacement of sucrose with erythritol revealed no difference. However, lower degree of sensory qualities (except hardness) liking of 75 and 100% erythritol cookies was observed. PRACTICAL APPLICATIONS Sucrose is one of the principal ingredients of cookies. But a sucrose-rich diet had been proven to be associated with lipogenesis and obesity. Erythritol is a sugar alcohol and has a good tolerance by humans. It is a noncariogenic, nonglycemic and low-calorie sweetener that is safe for diabetics. In addition, it possesses antioxidant properties. The study explores the possibility of utilizing erythritol to produce acceptable cookies. [source]

EFFECTS OF ANTIOXIDANTS ON IRRADIATED BEEF COLOR

JOURNAL OF FOOD QUALITY, Issue 3 2010
LAKSHMANAN RAMAMOORTHI
ABSTRACT Fresh beef was dipped into ascorbic acid (AA; 500 ppm), butylated hydroxyanisole (BHA, 150 ppm), butylated hydroxytoluene (BHT, 100 ppm) or propyl gallate (PG; 100 ppm); control samples were dipped in deionized water. Samples were vacuum packaged, then irradiated (0, 1.25 or 2.50 kGy). After irradiation, samples were stored (0, 7 or 14 days) at 4C. Color was assessed instrumentally (L*, a*, b*values, hue angles, chroma) and visually. All antioxidants increased L*value by two units (lighter); however, irradiation dose had no effect. Irradiation increased wet dog and rancid odors of beef; however, it decreased sour odor, a*value, chroma and hue angle, and increased visual green and brown colors, indicating that it reduced redness and color intensity. Antioxidants reduced L*(decreased lightening) and a*values (redness) compared to controls. BHA had the greatest effect on a*value. AA decreased visual green color the most; however, BHA and BHT were also effective. Antioxidants had inconsistent effects on b*value, chroma and hue angle. Storage decreased L*and a*values, and chroma. BHA and PG were most effective at maintaining low thiobarbituric acid-reactive substances when samples were irradiated. PRACTICAL APPLICATIONS Irradiation has the potential to reduce microbial load, increasing both the safety and shelf life of red meat products; however, it has the potential to damage fresh meat color, resulting in unacceptable discoloration. Irradiation can increase off-odors (wet dog, rancid) of beef; however, it can decrease sour odor, instrumental measures of red color, and increase visual green and brown colors. Use of antioxidants including ascorbic acid, butylated hydroxytoluene, butylated hydroxyanisole and propyl gallate can help maintain the color of irradiated beef held in refrigerated storage for up to 2 weeks. [source]

Reduction of Oil Absorption in Deep-Fried, Battered, and Breaded Chicken Patties Using Whey Protein Isolate as a Postbreading Dip: Effect on Flavor, Color, and Texture

JOURNAL OF FOOD SCIENCE, Issue 1 2009
E. Mah
ABSTRACT:, The effect of the application of whey protein isolate (WPI) solution as a postbreading dip to reduce oil absorption in deep-fried, battered, and breaded chicken patties on sensory properties was investigated. Chicken patties were battered, breaded with either crackermeal (CMP) or Japanese breadcrumbs (JBP), and dipped into WPI solutions at varying protein concentrations (0%, 2.5%, 5%, and 10%[w/w] WPI) and pH levels (pH 2, 3, and 8). A trained descriptive sensory panel evaluated the patties for 16 attributes relating to appearance, texture, and flavor. Instrumental analysis on the color and texture of the patties was also performed. The only perceivable changes in treated patties were related to color, hardness, and crunchiness. Increasing WPI concentration caused darkening of JBP but made CMP lighter. Patties treated at pH 8 were significantly darker across all WPI concentrations. The presence of WPI increased hardness and crust fracture for CMP but not JBP. Variations in pH levels did not affect texture. Thus, JBP that showed the highest lipid reduction (10% WPI at pH 2) were observed to be darker, less yellow, but did not produce any perceivable changes in hardness or crunchiness, while CMP with the lowest lipid content (5% WPI at pH 2) were lighter, more yellow, harder, and crunchier. [source]

Functionality of Soymilk Powder and Its Components in Fresh Soy Bread

JOURNAL OF FOOD SCIENCE, Issue 4 2008
D. Nilufer
ABSTRACT:, The physicochemical changes upon addition of soymilk powder (SMP) to soy bread were investigated. Two-pound loaves of soy bread were produced with components (soluble fiber [SF], insoluble fiber [ISF], soy protein) that mimic those levels contributed by SMP. Soy flour and soy flour/SMP soy breads served as controls. The following were determined for all breads produced: physical properties (loaf volume, crust, and crumb color); chemical compositions (SF and ISF contents, protein and ash contents); and physicochemical properties (water activity, total moisture content by thermogravimetric analysis [TGA], "freezable" water [FW], "unfreezable" water [UFW] content by DSC, stiffness at 25 °C by dynamic mechanical analysis [DMA], and firmness with Instron testing machine). SMP contained significant amounts of SF aside from the ISF fraction and mostly denatured soy protein. SMP addition to soy bread formulation significantly decreased loaf volume with respect to control soy bread, which can be attributed to the ISF and SPI contents of this ingredient. Other effects of SMP were found to be lighter and yellowish crumb color, darker crust color, and increase in firmness, as well as no change in moisture content, FW and UFW contents, water activity, and stiffness parameters. [source]

Retail Shelf-Life of Pork Dipped in Organic Acid before Modified Atmosphere or Vacuum Packaging

JOURNAL OF FOOD SCIENCE, Issue 8 2005
Nai-Yun Huang
ABSTRACT Modified atmosphere packaging (MAP) is increasingly popular for meat, but raw, chilled pork in vacuum or anoxic environments has a purple color. The retail shelf-life of pork chops dipped in 500 ppm ascorbic acid, 250 ppm citric acid, or no acid dip and stored at 1 °C before simulated retail display in MAP with gas exchange or air-permeable packaging after vacuum pouch storage was determined. The 80% N2:20% CO2 in MAP was exchanged with 80% O2:20% CO2, and chops were removed from vacuum packages and overwrapped with permeable film (VP-PVC) on the 7th day before simulated retail display at 4 °C. Shelf-life traits were determined at 1, 7, 8, 10, 12, and 14 d postpackaging. The pH values changed with time, but returned to post-dipped, prepackaged levels at the end of simulated retail storage. Weight loss of chops increased (P < 0.05) in VP-PVC compared with MAP. The a* values increased (P < 0.05) and L* and b* values decreased during simulated retail display, with higher L*, a*, and b* color values for chops in MAP than VP-PVC. Log numbers of psychrotrophic microorganisms were higher (P < 0.05) on VP-PVC samples than for chops in MAP on days 12 and 14. Psychrotrophic counts on ascorbic acid-treated samples were decreased compared with citric acid or no dipping on pork during simulated retail display. Pork chops in MAP with gas exchange had lighter and redder color, increased weight retention, decreased psychrotrophic counts, and increased lipid oxidation compared with conventional vacuum and overwrap packaging systems. [source]

Effects of Bleaching on the Properties of Roasted Sesame Oil

JOURNAL OF FOOD SCIENCE, Issue 1 2005
Inhwan Kim
ABSTRACT: Improvement in quality of roasted sesame oil was studied. Roasted sesame oil was bleached at 70 °C, 85 °C, or 100 °C for 20 min with acid-activated clay at 0.5%, 1.0%, or 3.0% (w/w) and then centrifuging at 12096 × g at 4 °C for 10 min. The color of the roasted sesame oil became lighter and the viscosity of oil decreased by bleaching. Bleaching caused a significant increase in the smoke point of the oil, from 170 °C to a range of 183 °C to 191 °C. Bleaching increased palmitic acid and decreased linoleic acid contents of roasted sesame oil. Bleaching decreased free fatty acid (FFA) and conjugated dienoic acid (CDA) contents and carbonyl values (CV) of roasted sesame oil. The more the acid clay was used, the lower were the FFA and CDA contents and CV of the oil. Amount of acid clay in bleaching of roasted sesame oil had higher effects on the color, viscosity, smoke point, FFA and CDA contents, and CV of roasted sesame oil than the bleaching temperature. Bleaching did not show a significant effect on tocopherol contents of the sesame oil. Bleaching tended to decrease sesamolin contents and increase sesamol contents in the roasted sesame oil. As the amount of acid clay and the bleaching temperature increased, the contents of sesamin and sesamolin in the oil decreased while sesamol contents increased. [source]

Internal Premature Browning in Cooked Steaks from Enhanced Beef Round Muscles Packaged in High-oxygen and Ultra-low Oxygen Modified Atmospheres

JOURNAL OF FOOD SCIENCE, Issue 2 2004
M. SEYFERT
ABSTRACT: Beef round muscles were injection-enhanced to 6%, packaged in high-oxygen (HiOx) or ultra-low oxygen (LoOx) modified atmospheres, stored 7 d and displayed 2 d (HiOx) or stored 16 d and displayed 1 d (LoOx) at 0 °C, and cooked to 71.1 °C. Raw internal color for steaks in HiOx was lighter, redder, more yellow and saturated, and had more oxymyoglobin and less deoxymyoglobin than steaks in LoOx (P < 0.0001). Cooked internal color of steaks from HiOx appeared prematurely brown and was darker, less red, yellow, and saturated, and had more denatured myoglobin than steaks from LoOx (P < 0.0001). This study presents conclusive evidence that modified-atmosphere packaging influences internal cooked color development of beef steaks. [source]