bluuebunny/crossref_metadata_2025 huggingface dataset:
Morphological aspects of rabbit masseter muscle after cervical sympathectomy
Authors: Pai‐Silva Maeli Dal , Ueda Anete Kinumi , Resende LuiZ.A.L. , Pai Vitalino DaL. , Alves Armando , Faleiros Antônio Tadeu Souza , De Castro Rodrigues Antonio
Published: December 2004

The objective of this paper was to study the effect of sympathetic innervation on morphological and histochemical aspects of skeletal muscle tissue. Rabbit masseter muscle was studied using histochemical and immunohistochemical methods for periods of up to 18 months post‐sympathectomy. The morphological and enzymatic characteristics of control masseter muscles were similar on both the left and right sides. The main features were muscle fibres with a mosaic pattern and a predominance of type IIa fibres, followed by type I. Type IIb fibres showed very low frequency. Sympathectomized animals showed varying degrees of metabolic and morphological alterations, especially 18 months after sympathectomy. The first five groups showed a higher frequency of type I fibres, whilst the oldest group showed a higher frequency of type IIb fibres. In the oldest group, a significant variation in fibre diameter was observed. Many fibres showed small diameter, atrophy, hypertrophy, splitting, and necrosis. Areas with fibrosis were observed. Thus cervical sympathectomy induced morphological alterations in the masseter muscles. These alterations were, in part, similar to both denervation and myopathy. These findings indicate that sympathetic innervation contributes to the maintenance of the morphological and metabolic features of masseter muscle fibres.
Production and distribution of interleukin 15 and its receptors (IL‐15Rα and IL‐R2β) in the implant interface tissues obtained during revision of failed total joint replacement
Authors: Saeed S. , Revell P.A.
Published: December 2004

Failure of total joint replacement (TJR) is a major problem and it is estimated that 15–20% of TJR will fail within 5–10 years after implantation. Most TJR is attributed to aseptic loosening of the implants in association with resorption of related bone due to the release of bone‐associated cytokines. IL‐15 is a cytokine that activates T cells and natural killer (NK) cells. IL‐15 protein is ubiquitous and is expressed in many tissues and cell types. Using immunohistochemical techniques, we demonstrated the expression of IL‐15 and its receptors IL‐15Rα and IL‐2Rβ in the interface tissues obtained from revision surgery. Both IL‐15 protein and IL‐15Rα were observed in macrophages, multinucleated giant cells and endothelial cells around blood vessels. Both the SDS‐PAGE and western blot revealed multiple bands and after stages of glycosylation, this resulted in a band at 13 KDa which corresponds to the IL‐15 protein. Again RT‐PCR results demonstrated a band of 420 bp corresponding to the IL‐15 protein. In addition, using U937 cells, the expression of both IL‐15 protein and IL‐15Rα were considerably up‐regulated when challenged with retrieved metal particles. Our results illustrated the IL‐15 to be an intact protein and that it is stored in the cytoplasm. A dye exclusion cell viability test displayed an increase in toxicity with an increase in the amount of metal particles added. There was a discrepancy between abundant IL‐15 mRNA, intracellularly detectable IL‐15 protein and apparently inefficient secretion. This suggests that IL‐15 protein production is predominantly regulated post‐transcriptionally and this is indicated by its strict regulation, especially at cell trafficking. Finally, unlike IL‐2, IL‐15 plays a certain role in bone resorption that leads to failed joint prostheses. It is apparent that this cytokine is an important T cell mediated immune response which needs further research.
The functions of cytokines and their uses in toxicology
Authors: Foster John R.
Published: December 2004

Cytokines are critical controllers of cell, and hence tissue, growth, migration, development and differentiation. The family includes the inflammatory cytokines such as the interleukins and interferons, growth factors such as epidermal and hepatocyte growth factor and chemokines such as the macrophage inflammatory proteins, MIP‐1α and MIP‐1β. They do not include the peptide and steroid hormones of the endocrine system. Cytokines have important roles in chemically induced tissue damage repair, in cancer development and progression, in the control of cell replication and apoptosis, and in the modulation of immune reactions such as sensitization. They have the potential for being sensitive markers of chemically induced perturbations in function but from a toxicological point of view, the detection of cytokine changes in the whole animal is limited by the fact that they are locally released, with plasma measures being generally unreliable or irrelevant, and they have short half lives which require precise timing to detect. Even where methodology is adequate the interpretation of the downstream effects of high, local concentrations of a particular cytokine is problematic because of their interdependence and the pleiotropism of their action. A range of techniques exist for their measurement including those dependent upon antibodies specific for the respective cytokines, but with the introduction of genomic and proteomic technology, a more complete study of cytokine changes occurring under the influence of chemical toxicity should be possible. Their further study, as markers of chemical toxicity, will undoubtedly lead to a greater understanding of how synthetic molecules perturb normal cell biology and if, and how, this can be avoided by more intuitive molecular design in the future.
Preparation of spent brewer's yeast β‐glucans for potential applications in the food industry
Authors: Thammakiti Saowanee , Suphantharika Manop , Phaesuwan Thanaporn , Verduyn Cornel
Published: December 2004

A preparation of β‐glucan, obtained from spent brewer's yeast, was evaluated for potential food applications. This material was autolysed and the cell walls that were obtained were homogenized, extracted firstly with alkali, then with acid, and then spray dried. Effects of the homogenization on the chemical composition, rheological properties and functional properties of β‐glucan were investigated. Homogenized cell walls exhibited higher β‐glucan content and apparent viscosity than those which had not been homogenized because of fragmentation of the cell walls. When compared with commercial β‐glucan from baker's yeast, it was found that the β‐glucan obtained from this study had higher apparent viscosity, water‐holding capacity and emulsion stabilizing capacity, but very similar oil‐binding capacity. These findings suggest that β‐glucan obtained from brewer's yeast can be used in food products as a thickening, water‐holding, or oil‐binding agent and emulsifying stabilizer.
The storage stability and textural, physico‐chemical and sensory quality of low‐fat ground pork patties with Carrageenan as fat replacer
Authors: Kumar Manish , Sharma B. D.
Published: December 2004

Low‐fat ground pork patties (<10% total fat) made with carrageenan added at either 0.25, 0.50 or 0.75% final concentration were processed and the compositional and sensory characteristics compared with control patties which contained 20% fat. The moisture content of raw and cooked low‐fat patties was significantly (P < 0.05) higher than control patties because of greater amounts of water added during formulation. Cooking yield, fat and moisture retention also improved significantly (P < 0.05) in low‐fat patties that had carrageenan incorporated when compared to a control product. The dimensions of the low‐fat patties were maintained better than those of the control product during cooking. The sensory attributes of low‐fat patties with 0.5% carrageenan were similar to those of the high‐fat control. The lipid profile revealed as much as a 47.7 or 44.1% decrease in total lipids and cholesterol content respectively, compared with the controls. The calorie content was reduced by 31.1% in low‐fat cooked patties compared with the controls. The texture profile of low‐fat patties that had been made with 0.5% carrageenan were similar to control patties with only a slight increase in hardness and gumminess in the low‐fat product. The low‐fat ground pork patties made in the present study remained stable without any appreciable loss of physico‐chemical, microbiological and organoleptic quality during refrigerated storage (4 ± 1 °C) for 21 and 35 days in aerobic and vacuum packaging respectively.
The effect of washing on physicochemical changes in packaged, sliced green peppers
Authors: Toivonen Peter M. A. , Stan Sabina
Published: December 2004

Whole green bell peppers (Capsicum annuum L.) were obtained through a local fresh‐cut company. They were washed in a 100 ppm chlorine solution, dried and then sliced into 0.5‐cm wide strips. A bulk sample of slices was divided into four treatments: (1) no wash, (2) one wash in fresh distilled water, (3) two sequential washes in fresh distilled water, and (4) three sequential washes in fresh distilled water. Retention of firmness of the pepper slices during storage at 7 °C improved with the number of washes after cutting. The modification of package atmosphere was less in all wash treatments than in the ‘no wash’ control. The sliced tissues of ‘no wash’ controls had higher levels of acetaldehyde and ethyl acetate. Analysis of the wash water revealed that sequential washes with water removed incremental amounts of acetaldehyde and soluble phenols from the cut surfaces of the tissue. These results show that washing has a dramatic effect on physicochemical measures of quality in green pepper slices, and it is likely that this effect is mediated by the removal of stress‐related compounds produced during the cutting operation. While acetaldehyde and total phenolics were the two stress‐related compounds measured in the wash water, it may be that other compounds removed in the wash water could have contributed to the beneficial effects on quality reported in this study.
Interactions between anthocyanins and organic food molecules in model systems
Authors: Mazzaracchio Palmira , Pifferi Piergiorgio , Kindt Maddalena , Munyaneza Athanase , Barbiroli Giancarlo
Published: December 2004

The interactions between different glucosidic anthocyanins (pelargonin, cyanin, delphinin, malvin and petunin) and some organic compounds (lactic, galacturonic, tannic, phenolic and sinapic acids; pyrogallol, furfural, pectin, cellulose, hydrolitic lignin) which are present in food‐stuffs were investigated at pH 3.0–4.3 and 25 °C. The interactions were monitored by means of u.v.‐VIS spectra and their different behaviours were highlighted by following changes in absorbance over a range of wavelengths (Δλ and ΔA). Significant effects on absorbance were detected and are discussed in terms of the phenomenon of co‐pigmentation.
Differences in nocturnal basal and rhythmic prolactin secretion in untreated compared to treated HIV‐infected men are associated with CD4+ T‐lymphocytes
Authors: Parra Adalberto , Reyes‐Terán Gustavo , Ramírez‐Peredo Jorge , Jacquemin Benedicte , Quiroz Verónica , Cárdenas MarÍo , García‐Sancho MarÍa Cecilia , Larrea Fernando
Published: December 2004

The existence of decreased hypothalamic dopaminergic tone in HIV‐infected men has been suggested. In a cross‐sectional study, we determined 12 h nocturnal basal and pulsatile prolactin (PRL) release levels (by blood sampling every 10 min) and their correlation with CD4+ T cells in seven volunteer HIV‐negative, healthy men (group 1), and 21 normoprolactinemic, euthyroid, HIV‐infected men divided into 3 groups (each group = 7): (i) group 2, asymptomatic HIV‐infected stage A1 men, untreated; (ii) group 3, AIDS stage C3 without active opportunistic infections, untreated; and (iii) group 4, previously stage C3 after at least 6 months of successful highly active antiretroviral therapy. Serum PRL was measured by radioimmunoanalysis and the results were analysed by waveform‐independent deconvolution analysis. CD4+ T lymphocytes were measured by flow cytometry and viral load by a nucleic acid sequence‐based amplification assay. No differences were detected in the first two groups. In the third group, however, 100% of prolactin secretion was found to be pulsatile with a shorter secretory burst duration (P = 0.04), and a greater circulating half‐life and pulse amplitude (P ≤ 0.04). Group 4 had the greatest basal prolactin secretion (P ≤ 0.04), and a shorter secretory burst duration (P = 0.04 vs group 2), circulating half‐life (P = 0.01 vs group 3) and intersecretory burst interval (P = 0.06 vs group 1). PRL approximate entropy was similar among all groups. Linear correlations existed between CD4+ T cell counts and PRL secretory burst half duration (r = 0.62, P = 0.002) and amplitude (r = −0.63, P = 0.001), and in circulating serum half‐life (r = − 0.61, P = 0.002) in HIV‐infected groups. Viral load showed no correlations. It is suggested that differential changes in nocturnal prolactin secretion among HIV‐infected men occurred while maintaining the normal coordinate feedback and/or feedforward control within the lactotropic axis. These changes may represent an adaptative mechanism to sustain, by different means, the maximal physiologic PRL production to stimulate the highest cellular immune response and/or reconstitution in attempting to survive.
Lack of CD28 expression on HIV‐specific cytotoxic T lymphocytes is associated with disease progression
Authors: Gamberg Jane , Pardoe Ingrid , Bowmer M Ian , Howley Constance , Grant Michael
Published: December 2004

During HIV infection, CD8+ T cells lacking the costimulatory molecule CD28 increase in number and proportion. This accumulation is associated with disease activity and possibly with CD8+ T‐cell dysfunction. In this study, CD8+CD28+ and CD8+CD28− T cells from 41 HIV‐infected individuals at various stages of disease were compared in terms of HIV‐specific cytotoxicity, TCRβV repertoire diversity, and cytokine production. We found that the CD28 phenotype of anti‐HIV CTL evolves in parallel with disease progression and disease activity. Absolute numbers of CD4+ T cells and CD4+/CD8+ T‐cell ratios progressively decreased in 3 groups with an increasing prevalence of CD28− HIV‐specific CTL. Conversely, HIV replication levels progressively increased in parallel with the prevalence of CD28− HIV‐specific CTL. Repertoire diversity at the level of TCRβV gene family expression was maintained at normal levels for both CD28+ and CD28− T cells at all stages of infection. Diversity at the level of junctional length polymorphism was more restricted in the CD8+CD28− T‐cell population, but this difference remained relatively constant through different stages of infection. Both CD28+ and CD28− T cells produced IL‐2 and IFN‐γ, regardless of disease stage and/or the predominant CD28 phenotype of anti‐HIV CTL.
Modelling the impact of antigen kinetics on T‐cell activation and response
Authors: Chao Dennis L , Davenport Miles P , Forrest Stephanie , Perelson Alan S
Published: December 2004

Cytotoxic T lymphocyte (CTL) responses are thought to be important for the control of many viral and other infections. Qualitative aspects of the CTL response, including the epitope specificity, affinity, and clonal composition, may affect the ability of T cells to mediate infection control. Although it is clear that the mode of introduction and the dose of antigen can affect these qualitative aspects of the response, little is understood of the mechanisms. We have developed an in silico model of the CTL response, which we use to study the impact of antigen dose, antigen kinetics and repeated antigen delivery on the response. The results suggest that recent observations on differences in response to killed antigen can be explained simply by differences in timing of T‐cell activation. These findings may provide insight into how different vaccination strategies can quantitatively and qualitatively affect the outcome of the immune response.
On the dynamics of T‐cell activation in lymph nodes
Authors: Hommel Mirja
Published: December 2004

The immune system is a complex network comprising many different organs and cell types, all of which have to work together in a highly accurate manner to exert their function. How is it, then, that the key players of adaptive immunity, T cells, B cells and dendritic cells (DC) move through this network? How is compartmentalization maintained and how do they interact? Over the past decade much attention has been paid to how and where T‐cell/DC interactions take place, but only recently − with the advent of new techniques − has research been directed to investigate ‘live’ T‐cell/DC interactions ex vivo and in situ. Whereas the overall sequence of events leading to T‐cell activation is largely undisputed, many of the cellular and molecular details of early T‐cell priming remain undefined or controversial. This review will focus on recent findings and discuss their implications for T‐cell activation.
Profiling the CD8low phenotype, an alternative career choice for CD8 T cells during primary differentiation
Authors: Kienzle Norbert , Baz Adriana , Kelso Anne
Published: December 2004

A CD8+ T cell of naive phenotype has multiple career choices during its primary differentiation into an effector cell population. One of these career options is becoming a CD8low T cell. We have previously shown by in vitro studies that CD8low T cells have lost expression of CD8 surface protein and mRNA and are poorly cytolytic. In line with poor cytolytic function, CD8low T cells express low levels of perforin and granzyme B and C, mediators of the granule‐exocytosis machinery. However, CD8low T cells express IFN‐γ and substantial amounts of IL‐4, the signature cytokines of type 1 and type 2 T‐cell polarization, respectively. Here, we argue that the CD8low phenotype is an alternative career choice for any naive CD8+ T cell during primary activation but that the probability of choosing this option is greatly enhanced by both IL‐4 and strong activation conditions. CD8low T cells have downregulated CD8α/β heterodimers and no preferential CD8α/α homodimer expression. As shown by anti‐CD8 Ab blocking experiments, surface CD8 substantially contributes to the CD8 T cell's effector function (i.e. cytokine expression and cytolytic activity). The distinct effector profile of CD8low T cells gives an example of the complexity of different CD8 T cell careers during primary effector differentiation.
Activated human dendritic cells express inducible cyclo‐oxygenase and synthesize prostaglandin E2 but not prostaglandin D2
Authors: Fogel‐Petrovic Mirjana , Long Julie A , Knight Darryl A , Thompson Philip J , Upham John W
Published: December 2004

Prostaglandins (PG) are well known lipid mediators with important immunoregulatory properties. While exogenous PGE2 has the ability to modulate the function and maturation of antigen presenting cells, such as dendritic cells (DC), it is not clear whether human DC have the capacity to synthesize PGE2 and other prostaglandins themselves. We therefore examined the expression of inducible cyclo‐oxygenase (COX‐2) by monocyte derived DC and the production of PGE2 and PGD2. Both monocyte derived DC and freshly isolated blood myeloid DC expressed little COX‐2 constitutively, though COX‐2 expression was rapidly but transiently upregulated in response to lipopolysaccharide stimulation. COX‐2 mRNA was detectable within 1 h of LPS exposure, peaked at 4−6 h, and rapidly declined thereafter. COX‐2 expression was accompanied by DC synthesis of PGE2, with peak levels present at 6−18 h post‐stimulation. In contrast, PGD2 synthesis was not detected at any time point. When DC were activated with LPS in the presence of nimesulide, a COX‐2 selective inhibitor, IL‐10 synthesis was inhibited, indicating that endogenous prostaglandins regulate DC cytokine production. PGE2 production by DC may therefore modulate DC and T‐cell function, thereby shaping the character of the immune response.
The creation of a large UK‐based multicentre cohort of HIV‐infected individuals: The UK Collaborative HIV Cohort (UK CHIC) Study
Authors:   The UK Collaborative HIV Cohort Steering Committee
Published: December 2004

Objectives

This paper describes the development of the UK Collaborative HIV Cohort (CHIC) Study. The aim of the study is to collate routinely collected data on HIV‐infected individuals attending one of seven clinical centres in the UK since 1 January 1996, with the objectives of describing changes over time in the frequency of AIDS‐defining illnesses, describing the uptake of and response to highly active antiretroviral therapy (HAART), and identifying factors associated with virological and immunological responses to HAART.

Methods

By December 2002, demographic, clinical and laboratory data had been collected on HIV‐positive patients seen at six of the seven HIV centres. Missing and inconsistent data had been investigated and the datasets audited. Records identified as relating to the same patient had been merged, and cross‐checks made with UK death registers to improve the accuracy of death reporting.

Results

The cohort currently contains information on 13 833 individuals. Eighty‐two per cent of the cohort are male, and the median age was 34 years at first follow‐up. The main risk factors for HIV infection have been determined as sex between men (63%) and sex between men and women (24%). Twenty‐five per cent of the cohort are known to have developed AIDS, and 8% have died.

Conclusions

The UK CHIC Study provides important information on the status of individuals infected with HIV in the UK, and provides a means to study the response to HAART and to monitor changes in the clinical event and death rates that have occurred since the introduction of HAART in the UK.
A cross‐cultural exploration of materialism in adolescents
Authors: Schaefer Allen D. , Hermans Charles M. , Parker R. Stephen
Published: December 2004

To date, few studies have empirically examined specific values with respect to the global teenager hypothesis. In testing the global teenager hypothesis, this study investigates similarities and differences in materialism among 14‐ to 17‐year olds in China, Japan and the USA. Significant differences were found between respondents from the three nations for materialism and discretionary spending power. Discretionary spending power had a significant effect on materialism across nations. In addition, evidence supports cross‐national differences in the psychological structure of the materialism construct. While personal gain and social gain explain two materialism dimensions for the Japanese and American samples, factor analysis results suggest materialism may have alternative conceptual underpinnings in China. The findings of this study generally fail to support the global teenager hypothesis as it relates to the value of materialism.
Children's advertising: the ethics of economic socialisation
Authors: Preston Chris
Published: December 2004

There is focus upon advertising and children for two broad reasons. First, it is because children are children, and are considered separately. Second, it is because children will become adults. Advertising therefore effects behaviour during childhood and continues to do so into adulthood. Advertising to children rarely receives a good press, and it remains a controversial topic in the wider domain. Is it responsible for poor diet? Does it make children pester their parents? Is there too much of it? And does Christmas have to start in September? Subsequently the issue has evolved to question whether there should be advertising to children, and if so whether it should be regulated. This discussion paper examines arguments for and against children's advertising, and concludes that whilst there are compelling arguments on both sides, advertising to children remains an economic necessity in need of adjustment and regulation.
Consumer education: creating consumer awareness among adolescents in Botswana
Authors: Makela Carole J. , Peters Selinah
Published: December 2004

Senior secondary schools’ students in Botswana were studied to determine their awareness of consumer rights and responsibilities and their perceptions of consumer behaviour and consumer education. Recommendations will inform the refinement of consumer education teaching in Botswana as well as other secondary education programmes. A questionnaire suitable for this study was used to collect data. Responses from 3107 students were received. Descriptive statistical analysis was used to determine frequencies and central tendencies. Chi‐square tests were computed to examine relationships among variables by gender, class level, and school location. Two‐thirds of the students correctly identified consumer rights and responsibilities. Female students were more likely to identify consumer rights and responsibilities than males. Students agreed that they were informed on consumer issues and females were more likely to be informed than males. Topics identified to be taught in consumer education included consumer rights and responsibilities, purchasing decisions, advertising and others. The delivery methods identified were classes in school, workshops, radio and television programmes, and consumer youth clubs. Consumer education programmes were found to have an impact on adolescents because most of them were aware of consumer rights and responsibilities and acted as informed consumers on most consumer issues.
The use of electronic books in midwifery education: the student perspective
Authors: Appleton Leo
Published: December 2004

The objectives of this paper are: (i) to illustrate the use of e‐books by health studies students at a college of higher education; (ii) to provide a demonstration of how e‐books may be facilitated by library and information services staff working across the health and academic sectors; (iii) to comment upon the experiences of health studies students, in using e‐books. A focus group of 10 student midwives was used to gain insight into how e‐books may be used in an academic context for health professionals. The findings of the student midwives’ focus group are reported and discussed. In this instance, the student midwives were encouraged to use e‐books as part of a structured information skills programme. The paper concentrates on how the e‐books were used within this context and addresses the potential benefits and disadvantages from a student perspective. The results provide evidence of a largely positive experience of using e‐books as an electronic information resource. The focus group reveals many benefits and advantages in the facilitation and use of e‐books, as well as addressing areas for development. It is concluded that e‐books have a place in health library and information resources, but further development of e‐books and e‐book collections is required and subsequent investigation into their most effective use.
Marketing and health libraries
Authors: Wakeham Maurice
Published: December 2004

Aim:  To present an overview of the concepts of marketing and to examine ways in which they can be applied to health libraries.

Methods:  A review was carried out of literature relating to health libraries using lisa, cinahl, bni and Google.

Results:  Marketing is seen as a strategic management activity aimed at developing customer relationships. Concepts such as the ‘four Ps’ (product, price, place and promotion), marketing plans, the marketing mix, segmentation, promotion and evaluation are identified and discussed in relation to health libraries.

Conclusion:  In increasingly complex health service and information environments, the marketing and promotion of library services is becoming more important if those services are to justify the resources given to them. Marketing techniques are equally applicable to physical and digital library services.
Interlocality variation in speed of moult in the Citril Finch Serinus citrinella
Authors: Borras A. , Cabrera T. , Cabrera J. , Senar J. C.
Published: December 2004

The speed of avian moult has been related to body condition, and this to habitat quality. These facts suggest a relationship between habitat quality and moult speed. We looked for evidence of such a relationship in the Citril Finch Serinus citrinella in the Pyrenees, where, because of a Mediterranean influence, there is an important bioclimatic contrast between north‐ and south‐facing slopes of the same mountain. This contrast strongly affects the general body condition of birds there (higher body mass, fat score and survival on north‐facing slopes). Citril Finches in the higher quality area moulted more rapidly (measured as residual wing raggedness) than those in the lower quality area, the two sampling localities being only 5 km apart. As the birds initiated moult at the same time in the two locations, this difference in speed cannot have resulted from a differential effect of photoperiod. This stresses the importance of habitat selection, even at very small scales, for the completion of moult.
The distribution and population of the Seychelles (Bare‐legged) Scops Owl Otus insularis on Mahé: consequences for conservation
Authors: Currie Dave , Fanchette Rodney , Millett James , Hoareau Camille , Shah Nirmal J.
Published: December 2004

This study details the first baseline survey of the Critically Endangered Seychelles Scops Owl Otus insularis, currently only recorded from the 152‐km2 island of Mahé, the largest and highest island in the granitic Seychelles, western Indian Ocean. A survey was conducted in October 2000–March 2001 using playback of conspecific calls in random squares (500 m × 500 m) with midpoints being at least equal to 100 m asl. Playback was conducted in 159 of a possible 375 squares (42%). Territorial responses were detected in 60 of 159 (38%) squares, which represented an estimated 70 distinct territorial responses. Pairs responded in 51% and single birds responded in 49% of squares where a response was elicited. Scops Owls were more likely to be detected at higher altitudes, in mixed forest, and sympatrically with endemic frogs (Tachycnemis seychellensis and Sooglossus spp.). Two models were used to predict population: one based exclusively on altitude resulted in a population estimate of 134–159 territories (268–318 individuals) within a 34‐km2 range, whereas a second incorporating altitude and vegetation, which excluded unsuitable habitat, resulted in an estimate of 125–142 territories (250–284 individuals) in a 31‐km2 range. We discuss the implications of our findings to the Owl's conservation status and management.
Components of phenotypic variation in the morphometrics of shearwater (Puffinus) species
Authors: Bull Leigh S. , Haywood JOHN , Pledger Shirley
Published: December 2004

Coefficients of variation were used to examine the variability of bill, wing and foot measurements of 11 sexually size dimorphic and seven monomorphic shearwater (Puffinus) species, and to investigate the selective regimes that may be acting on these traits. The effects of phylogeny can lead to a lack of statistical independence among interspecies data, so randomization tests were performed in addition to standard statistical approaches, which assume independence. However, the results obtained from the two approaches always agreed. Among the 18 species, bill measurements were significantly more variable than those of the wing or foot; furthermore, bill depth dimensions exhibited the greatest amount of phenotypic variation. Both sexually monomorphic and sexually dimorphic species exhibited the same patterns of phenotypic variation. In the sexually dimorphic species, patterns of trait variation did not differ significantly between sexes. The findings suggest that variation in the bill of dimorphicPuffinusspecies is not due to sexual selection. More probably, variability among the traits is due to differences in the strength of natural selection, with those traits under strong stabilizing selection (e.g. wing, tarsus and mid‐toe) exhibiting reduced variability, as optimum physical dimensions are being selected for.
Do body condition and plumage during fuelling predict northwards departure dates of Great Knots Calidris tenuirostris from north‐west Australia?
Authors: Battley Phil F. , Piersma Theunis , Rogers Danny I. , Dekinga Anne , Spaans Bernard , Van Gils Jan A.
Published: December 2004

It is often assumed that strong selection pressures give rise to trade‐offs between body condition and time in long‐distance migrating birds. Birds that are ‘behind schedule’ in fuel deposition or moult should delay departure, and this should result in a negative correlation between initial condition and departure date. We tested this hypothesis in the Great Knot Calidris tenuirostris migrating from north‐west Australia to eastern Asia en route to Siberia. Great Knot gain mass and moult into breeding plumage before leaving northern Australia in late March and early April, and fly 5400–6000 km to eastern China and Korea. We radiotracked 27 individuals (17 males and ten females) to determine departure dates; 23 migrated and four remained in Australia. We characterized body condition at capture using body mass, predicted pectoral muscle mass (based on ultrasound estimates of the size of the pectoral muscles) and breeding plumage scores. Residual condition indices were uncorrelated, indicating that at the individual level, variation in one fuelling component was not strongly associated with variation in the other components. Birds that did not depart had lower residual body mass and breeding plumage indices than those that did migrate; these four birds may have been subadults. Neither sex, size nor the condition indices explained variation in departure date of migrants. Reasons for this are explored. Departure dates for northward migrating waders indicate that the migration window (span over which birds depart) decreases with proximity to the northern breeding grounds. We suggest that migration schedules become tighter as birds get nearer to the breeding grounds. Thus the lack of a relationship between condition and departure date in Great Knots may reflect the fact that the departure episode under study is the first one in sequence and is still 4–8 weeks before breeding.
Effects of weather on the survival and growth of CorncrakeCrex crexchicks
Authors: Tyler G. A. , Green R. E.
Published: December 2004

Weather conditions during the early life of precocial chicks of some bird species have marked effects on survival and may also cause changes in adult population size. In this paper, we use data from broods with radiotagged mothers to examine correlations of growth rates and survival of CorncrakeCrex crexchicks in Scotland and Ireland with temperature and rainfall. The loss of whole broods before they reached independence was infrequent and not correlated with temperature or rainfall. Loss of some chicks from broods before independence usually occurred and multiple regression analysis indicated that the proportion of chicks that survived increased with decreasing initial brood size, increasing temperature and decreasing rainfall. However, the magnitude of the effects of weather on survival were quite small. The rate of weight gain of chicks varied considerably within and among broods. The mean daily weight gain rate of broods decreased significantly with increasing rainfall, and variation in the weight of chicks within broods was greater for broods whose mean rate of weight gain was low.
Vocal mimicry by the Black‐browed Reed Warbler Acrocephalus bistrigiceps: objective identification of mimetic sounds
Authors: Hamao Shoji , Eda‐Fujiwara Hiroko
Published: December 2004

Vocal mimicry by the Black‐browed Reed Warbler Acrocephalus bistrigiceps was investigated. To identify mimicry objectively, we measured similarities between the sounds of models and those of Warblers by means of Principal Component Analysis (PCA) using a set of acoustic parameters. Of the sounds suspected of being mimicry according to visual inspection of sonagrams, only 57% were identifiable as mimicry according to PCA. Previous studies have not included quantitative criteria for assessing vocal mimicry, and our results suggest that judgements might not be reliable in the absence of objective criteria. Male Warblers incorporated the mimetic sounds into their songs, and each male mimicked 2–5 species. We found no evidence that females preferred males with large mimetic repertoires. This suggests that vocal mimicry has not evolved in response to selection by females in this species, although our analysis did not reveal entire mimetic repertoires in the Warbler songs.
The potential for interactions between predation and habitat change to cause population declines of farmland birds
Authors: Evans K. L.
Published: December 2004

Population declines are often attributed to either habitat change or increased predation rates, without a full consideration of the potential for these two factors to interact. This may lead to an inaccurate diagnosis of the causes of population decline and thus the selection of inappropriate management solutions. Here mechanisms through which habitat change and predation could interact are reviewed. Examples of how these may have contributed to population declines are provided, focusing on European farmland birds. However, very few appropriate studies have been conducted that allow the role of such interactions to be assessed accurately. To remedy this situation experimental designs that could detect the presence of interactive mechanisms are described. When habitat change and predation interact, conservation managers are provided with the opportunity to control predation impacts through habitat management rather than predator removal, which may provide a more cost‐effective management strategy.
Poor nutritional condition as a consequence of high dominance status in the Coal Tit Parus ater
Authors: Hay Jacqueline M. , Evans Peter R. , Ward Robin M. , Hamer Keith C.
Published: December 2004

The costs and benefits of dominance status have been investigated in the past and it has generally been reported that subdominant birds are at a nutritional disadvantage owing to their low dominance status. The nutritional condition of birds during winter can be important in determining their likelihood of survival. This is particularly so in small passerines that are sensitive to severe weather conditions. Ptilochronology is an accurate method used to produce a long‐term estimate of body condition spanning the number of days that it takes to grow a new feather. Ptilochronology was used during this study to estimate the nutritional condition of Coal Tits Parus ater during one winter and how condition was affected by dominance status. Dominant Coal Tits produced poorer quality feathers, which they grew at a slower rate, than did subdominant conspecifics. This study highlights a nutritional cost to high dominance status that could have long‐term consequences because the induced tail feathers will not be replaced for at least 5 months.
Causes of population declines of the Lesser Kestrel Falco naumanni in Israel
Authors: Liven‐Schulman Ifat , Leshem Yossi , Alon Dan , Yom‐Tov Yoram
Published: December 2004

We studied the ecology of the Lesser Kestrel Falco naumanni, a globally threatened species, to identify the factors causing its gradual decline in Israel, in order to stabilize and possibly restore its numbers. Lesser Kestrels in Israel breed in colonies, both adjacent to human settlements (rural and urban) and in the countryside, where they are found especially on cliffs. In this study, observations of Lesser Kestrels were carried out in three different breeding areas: (1) an urban colony in Jerusalem, (2) a rural colony in the Alona district and (3) a cliff in the Judean desert (open landscape colony) about 10 km east of Jerusalem. The number of fledglings per nest in Jerusalem (1.91) was lower than in Alona (2.44) and the cliff (3.16). As this lower productivity was associated neither with the clutch size, with hatching success, which were similar in all three regions (about four eggs per clutch, and 80% hatched, respectively), nor with egg fertility, it probably reflects factors operating during the nestling phase. We suggest that the two main factors limiting food availability and causing nestling deaths in Jerusalem are the relatively long flight distances between the breeding and hunting sites, and the use of pesticides in the city parks and lawns. Stochastic events superimposed on such factors, such as the drought of 1999, which markedly reduced productivity, may cause pronounced fluctuations eventually affecting long‐term population persistence.
Hatching asynchrony, sibling aggression and cannibalism in the Bearded VultureGypaetus barbatus
Authors: Margalida Antoni , Bertran Joan , Boudet Jennifer , Heredia Rafael
Published: December 2004

We report data on laying and hatching asynchrony in the Bearded VultureGypaetus barbatus, and provide the first detailed description of the provisioning of nestlings, sibling aggression and cannibalism. The results suggest that brood reduction was mediated through the age and size differences between siblings, which resulted in the superior competitive ability of the older chick. Thus, brood reduction occurred through starvation facilitated directly by the older chick's aggression. The results support the hypothesis that the second egg probably functions as insurance in case the first egg does not hatch. The insurance‐egg hypothesis is supported by the following facts: 1) in three of six breeding attempts, the second egg produced a chick when the first egg failed to hatch or the first chick died young. At least two of these B chicks fledged; 2) in the Bearded Vulture most breeding failures occur during the hatching period and thus the insurance value of last‐hatched eggs would be especially important in this species; 3) clutch replacement, an alternative to laying an insurance egg, is relatively uncommon in this species and 4) the laying interval (5–7 days) and the hatching asynchrony (5–8 days) of this species are the longest recorded in any raptor, suggesting that they might represent an adaptive mechanism facilitating the rapid loss of the second chick if the first one hatches.
Timing and duration of moult in three populations of Purple Sandpipers Calidris maritima with different moult/migration patterns
Authors: Summers Ron W. , Underhill Les G. , Nicoll Mike , Strann Karl‐Birger , Nilsen Stein Ø.
Published: December 2004

Timing and duration of primary moult in three populations of Purple Sandpipers Calidris maritima were described and discussed in relation to the birds’ need to complete moult before the onset of winter, when resources are required for survival. We predicted that moult would be completed earlier by birds wintering at higher latitudes. The south Norwegian breeding population, which moults and winters along the coast of east Britain (54–57°N) had a mean starting date of 21 July for primary moult (16 July for females and 24 July for males), a mean duration of 61 days, and completed on 20 September. Resident Icelandic (64–65°N) birds had a mean starting date of 22 July for primary moult (17 July for females and 25 July for males), a mean duration of 51 days, and completed on 11 September. Birds moulting in north Norway (70°N) arrived in north Norway in suspended primary moult or without having started moult, and completed it there. They had a mean completion date of 2 November for primary moult (31 October for females and 3 November for males). Starting date and duration could not be estimated because some suspended moult for an undetermined period, but it was thought that they started in late August. It is likely that most originated from Russia. The onset of moult appears to be set by the end of breeding and there is little overlap in these two events. The earlier start of moult by females in all three populations may be because they abandon the males when the chicks hatch, leaving the males to attend the chicks. Although the duration of primary moult followed the expected trend, being fastest in north Norway and slowest in Britain, the onset of moult was so late in north Norway that they had an unexpectedly late completion date, despite their rapid moult. The late completion of primary moult in north Norway suggests that wintering in the far north may not pose the energetic constraints on Purple Sandpipers that had previously been supposed.
Feeding ecology of the Common Tern Sterna hirundo in a wintering area in southern Brazil
Authors: Bugoni Leandro , Vooren Carolus Maria
Published: December 2004

The wintering diet of Common Terns Sterna hirundo was studied by using 714 pellets collected on roosting sites at the mouth of the Lagoa dos Patos and on adjacent coastal beaches, in Rio Grande do Sul, southern Brazil, from March 1999 to February 2000. A total of 12 340 individual prey items of 35 different food types was found. Fish was the most important food type in the diet, constituting 32% by number and 93% by mass. Insects contributed 67% by number but only 3% by mass. The main food types were sciaenid fishes Paralonchurus brasiliensis, Micropogonias furnieri, Cynoscion guatucupa and Macrodon ancylodon. Several of these are important commercial species; fisheries potentially impact food availability to the terns, and terns may contribute significantly to the natural mortality of these fishes. Clupeiform fishes, the urophycid fish Urophycis brasiliensis and flying ants (Camponotus sp.) were also important. Species composition of the diet (food types), both by number and by mass, differed significantly between months. Prey sizes ranged in length from 12.7 mm to 217.4 mm. The average estimated total length of fish taken was 77.7 mm, but the mean differed significantly among prey species. The importance of demersal sciaenids to the diet of the Common Tern, a surface predator, may be explained by their association with aquatic predators, especially adult Bluefish Pomatomus saltatrix and Striped Weakfish Cynoscion guatucupa, and the Franciscana Dolphin Pontoporia blainvillei, which drive these fish to the surface. The occurrence of flying ants in the diet was related to offshore winds, which carried these insects out to sea. The occasional high availability of insects possibly changed the cost/benefit relationship of several food types, causing diet changes. The high number of prey species, the temporal variations in the composition of the diet and the wide range of prey sizes are evidence of the high dietary plasticity of the Common Tern, at wintering areas in southern Brazil.
Offspring sex ratio in the Common Tern Sterna hirundo, a species with negligible sexual size dimorphism
Authors: Fletcher Kathy L. , Hamer Keith C.
Published: December 2004

In many vertebrates, male offspring are affected more than female offspring by adverse conditions during growth, resulting in facultative adjustment of offspring sex ratio by parents in response to social and environmental conditions during breeding. The greater vulnerability of male offspring is generally attributed to their higher energy requirements associated with their larger size, although greater sensitivity to adverse conditions could be related to other factors such as negative effects of androgens on male physiology. To control for sexual differences in body size, we examined variation in offspring sex ratio in the Common Tern Sterna hirundo, a species with negligible sexual size dimorphism. In this species, the last‐laid egg (termed the c‐egg) is smaller than the first two and hatches last, so that the chick obtains relatively little food and hence has a low probability of survival to fledging. This species thus provides a powerful model for examining sex‐linked mortality and sex ratio variation under natural conditions. We found that the sex ratio of c‐eggs, but not of earlier laid eggs, was significantly biased in favour of females. Chicks hatched from c‐eggs (termed c‐chicks) had low survival but female c‐chicks had significantly higher survival than male c‐chicks. These data provide strong evidence that factors other than sexual size dimorphism are responsible for producing greater vulnerability of male offspring to adverse conditions during growth.