bluuebunny/crossref_metadata_2025_split huggingface dataset:
Participatory evaluation (II) – translating concepts of reliability and validity in fieldwork
Authors: Crishna B. 
Published: September 2006

AbstractBackground  In developing countries participatory methods are a viable way of evaluating social development projects. It provides a means to look constructively at the strengths and weaknesses in projects, and use the lessons learned to improve planning and implementation. One of the challenges faced, however, is being able to ensure that the study is sound, reliable and valid, and that it is free from bias, thus making the final results trustworthy and of use to a larger population.Methods  This article looks at five steps involved in a participatory evaluation process and the ways in which reliability and validity have been considered.Results  Participatory studies may be different, but all have similar underlying principles as traditional quantitative and qualitative studies. Examples from fieldwork in Asia have been used to demonstrate how studies can be made credible, so that they have value, influence or the ability to encourage changes in thinking, while evaluating social development projects. At every stage, the role of the external evaluator remains crucial, and has to be that of a facilitator, encouraging participation from everyone.Conclusion  Hence project evaluations using such a method must be clear in how to remove bias and ensure reliability and validity in all the stages of the evaluation, from planning to making recommendations. Imaginative and alternative strategies need to be developed to examine reliability and validity in the qualitative evaluation.
Bacterial production in the carbon flow of a central European stream, the Breitenbach
Authors: MARXSEN JÜRGEN 
Published: September 2006

Summary1. Over the last 30 years, many investigations have been performed on the dynamics of bacteria and organic matter in the Breitenbach, a first‐order stream in central Germany. The data now available allow a synthesis of the role of bacteria in the carbon budget, as an example of the general importance of bacteria in stream ecosystems.2. Comparing measured and estimated inputs and outputs to the ecosystem, the organic matter budget of the Breitenbach is fairly balanced: 1.84 kg C m−2 year−1 (sum of inputs) versus 1.88 kg C m−2 year−1 (sum of outputs). No major missing link remains.3. The basis of the food web in the Breitenbach is mainly allochthonous organic matter (dissolved and particulate 1.02 and 0.42 kg C m−2 year−1, respectively). Autochthonous gross primary production is 0.4 kg C m−2 year−1. Most of the organic matter leaves the stream via transport to the River Fulda (dissolved and particulate 0.74 and 0.34 kg C m−2 year−1, respectively), the rest by respiration (0.80 kg C m−2 year−1 or 43% of total outputs).4. Bacteria constitute an important part (36%) of heterotrophic biomass (average: 0.004 kg m−2 bacterial C of 0.011 kg m−2 total heterotrophic C). Bacteria also account for the major fraction (71%) of heterotrophic production: 0.20 of 0.28 kg C m−2 year−1 total heterotrophic production. Bacterial production in the Breitenbach is similar in magnitude to the estimate of photoautotrophic net primary production: both approximately 0.20 kg C m−2 year−1.5. Protozoa, the main consumers of bacteria in the Breitenbach, consume approximately one‐third of bacterial production (0.07 kg C m−2 year−1). Small metazoa (meiofauna, <0.5 mm) play a lesser role in the consumption of bacteria, consuming <0.01 kg bacterial C m−2 year−1. Larger metazoa (macrofauna, >0.5 mm) consume approximately 10% of bacterial production. Although this is a considerable amount of the carbon resources needed by the macrofauna (0.02 kg C m−2 year−1 of bacterial production versus 0.06 kg C m−2 year−1 macrofauna production plus respiration), the carbon demand of the macrofaunal community is met to a larger extent by particulate organic matter than by bacteria.6. Bacteria are the main decomposers in the Breitenbach. They account for 78% of heterotrophic respiration (0.47 of 0.60 kg C m−2 year−1) and 59% of total respiration (0.47 of 0.80 kg C m−2 year−1).
Physiological constraints on contest behaviour
Authors: BRIFFA M. , SNEDDON L. U. 
Published: September 2006

Summary

Contests may involve injurious fighting, other types of direct physical aggression and communication. They occur over ownership access to mates and other resources that may increase an individual's attractiveness and its chance of survival. Traits that enhance resource holding potential may be the result of sexual selection, natural selection or a combination of both.
Agonistic behaviours are expected to be demanding to perform and costly in terms of changes in physiological state. The ability to meet the physiological costs may determine contest outcomes and constrain the intensity of agonistic activities.
The energetic costs have been investigated in a broad range of taxa using a variety of techniques. They include the mobilization of energy reserves, but a key cost in several taxa appears to be limited anaerobic capacity and subsequent accumulation of lactic acid. Androgens, stress hormones and neurohormones have also been shown to constrain fighting behaviour. However, due to key differences in the endocrine systems of vertebrates and invertebrates, the effects of hormones are far less consistent across taxa than in the case of metabolites.
Physiological constraints on fighting may vary according to their importance relative to circumstantial costs, the time‐scale over which they exert their effects, their effects on different roles and their causal links with behaviour. Incorporating these factors into theoretical studies of contest behaviour may give further insights of how the costs of fighting influence agonistic behaviour.
Climate change and bird phenology: a long‐term study in the Iberian Peninsula
Authors: GORDO OSCAR , SANZ JUAN JOSÉ 
Published: September 2006

AbstractMany studies in recent years have demonstrated long‐term temporal trends in biological parameters that can only be explained by climate change. Bird phenology has received great attention, as it studies one of the most conspicuous, popular, and easily observable phenomena in nature. There are many studies of long‐term changes in spring arrival dates, most of which concur with earlier records from the last few decades. However, few data are available for autumn departures or length of stays. Furthermore, existing data offer an equivocal picture. In this study, we analysed a huge database of about 44 000 records for five trans‐Saharan bird species (Ciconia ciconia, Cuculus canorus, Apus apus, Hirundo rustica and Luscinia megarhynchos). Data were collected from over 1300 sites around Spain during the period 1944–2004. Common spring arrival patterns were found in all species. Spring arrival dates have tended to advance since the mid‐1970s. Current dates are similar to those from the 1940s (except for C. ciconia). Thus, the advance of spring migration over the last three decades could be seen as a return to the initial timing of arrival dates, after abnormally delayed arrivals during the 1970s. A strong negative relationship with temperature in Spain at arrival time was observed in all species. A negative relationship with the Sahel Index (a measurement of precipitation in the African Sahel area during the rainy season) for the previous year was also found in C. canorus, A. apus and H. rustica. Regarding autumn departures, all species showed common interdecadal fluctuations, but only H. rustica is leaving earlier Spain at present. All species departed earlier in years that had higher temperatures during their reproductive period. However, only for H. rustica the relation between Spanish temperatures at departure time and the last sightings of individuals was significant. A heterogeneous temporal response for the length of stay was also found: C. ciconia increased, A. apus did not change and H. rustica decreased its stay. This is the first study, based on an extensive bird phenology observational network covering a large region, that shows the most complete and thorough analysis available for the Mediterranean region.
Pathology of fungal infections of the central nervous system: 17 years' experience from Southern India
Authors: Sundaram C , Umabala P , Laxmi V , Purohit A K , Prasad V S S V , Panigrahi M , Sahu B P , Sarathi M V , Kaul S , Borghain R , Meena A K , Jayalakshmi S S , Suvarna A , Mohandas S , Murthy J M K 
Published: September 2006

Aims:  To describe the pathology of central nervous system (CNS) fungal infections with particular reference to India.Methods and results:  This was a retrospective study from 1988 to 2004 constituting 130 cases. The diagnosis was based on morphology of biopsy/autopsy material. These included aspergillosis (n = 73), zygomycosis (n = 40), cryptococcosis (n = 2), rhodotorulosis (n = 1), candidiasis (n = 5), maduramycosis (n = 1), pheohyphomycosis (n = 3) and mixed infections (n = 5). Predisposing risk factors were present in 49 (38%) patients only. The majority of the patients were immunocompetent. The commonest risk factor was diabetes mellitus, the commonest route of infection was from a contiguous site and the commonest pathology was granuloma. Culture positivity was seen in only 31%.Conclusion:  Environmental factors in tropical countries such as India play a significant role in the pathogenesis of CNS fungal infections.
The contributions of age and sex to variation in common tern population growth rate
Authors: EZARD T.H.G. , BECKER P.H. , COULSON T. 
Published: September 2006

Abstract

The decomposition of population growth rate into contributions from different demographic rates has many applications, ranging from evolutionary biology to conservation and management. Demographic rates with low variance may be pivotal for population persistence, but variable rates can have a dramatic influence on population growth rate.
In this study, the mean and variance in population growth rate (λ) is decomposed into contributions from different ages and demographic rates using prospective and retrospective matrix analyses for male and female components of an increasing common tern (Sterna hirundo) population.
Three main results emerged: (1) subadult return was highly influential in prospective and retrospective analyses; (2) different age‐classes made different contributions to variation in λ: older age classes consistently produced offspring whereas young adults performed well only in high quality years; and (3) demographic rate covariation explained a significant proportion of variation in both sexes. A large contribution to λ did not imply a large contribution to its variation.
This decomposition strengthens the argument that the relationship between variation in demographic rates and variation in λ is complex. Understanding this relationship and its consequences for population persistence and evolutionary change demands closer examination of the lives, and deaths, of the individuals within populations within species.
Connecting variation in vegetation and stream flow: the role of geomorphic context in vegetation response to large floods along boreal rivers
Authors: RENÖFÄLT BIRGITTA MALM , MERRITT DAVID M. , NILSSON CHRISTER 
Published: September 2006

Summary

Flooding governs riparian plant diversity along boreal rivers but the ecological role of extreme floods is only partly understood. We studied the dynamics of riparian plant composition and richness in the free‐flowing Vindel River in northern Sweden, and the importance of reach type in sustaining high species richness.
We conducted three surveys of riparian plant species richness over a period of two decades. The first and last of these surveys were conducted 1–3 years after significant flooding and the second was carried out after a period of more moderate flooding.
Our results suggest that extreme floods reduce riparian plant species richness in tranquil (slow‐flowing) reaches but that a subsequent period of less extreme flood events facilitates recovery. Tranquil river reaches were also more prone to invasion by ruderal species following major floods. Species richness in turbulent reaches (rapids and runs) remained constant during all surveys. One possible explanation for this pattern is that tranquil reaches become more anoxic during floods because they have more fine‐grade soils with lower hydraulic conductivity than turbulent reaches. Anoxic conditions may cause stress and plant death, opening up space for colonization. Turbulent reaches maintain a better oxygenation in the root zone of plants through high groundwater turnover, reducing negative effects of prolonged floods.
The fact that turbulent reaches preserved species richness regardless of flood magnitude suggests that they are important for the resistance of riparian ecosystems to prolonged inundation. In contrast, tranquil reaches, with a higher water‐holding capacity, might instead maintain their species richness during drought periods.
Synthesis and applications. Our findings highlight the importance of spatial and temporal variation in riverine plant species richness and composition. To conserve these habitats at a landscape scale, a full range of reach types is necessary to allow for recovery in reaches where species richness has declined. To maintain healthy riparian zones, river managers should focus restoration efforts on interactions between hydrology, geomorphology and biota.
Spatial structure of roe deer populations: towards defining management units at a landscape scale
Authors: ZANNÈSE AUDREY , MORELLET NICOLAS , TARGHETTA CHIARA , COULON AURÉLIE , FUSER SIMONETTA , HEWISON A. J. MARK , RAMANZIN MAURIZIO 
Published: September 2006

Summary

A crucial question in wildlife management concerns the definition of ecologically meaningful management units. Management action needs to be co‐ordinated at the appropriate spatial scale. There are few practical tools for delimiting pertinent management units for large mammals such as ungulates.
Previous work has favoured a molecular approach to determine genetically distinct units, but this may be too costly for routine management. In addition, recent studies have revealed fine‐scale heterogeneity in population dynamics of free‐ranging ungulates in relation to environmental variability.
We combined spatial analysis of environmental heterogeneity (vegetation cover, topography and climate), animal morphology (jaw length) and genetic structure (microsatellites) to define biologically meaningful population units for roe deer Capreolus capreolus in the Belluno province, north‐eastern Italy. Jaw length is a sensitive measure of density‐dependence and a good proxy for spatial and temporal variation in roe deer population growth.
Spatial analysis of environmental variables suggested that the study area should be divided into two, or possibly four, biogeographical regions in relation to variation in altitude and habitat type. There was significant spatial variability in jaw length across the province that clustered into two main regions (with shorter jaws in the north compared with the south), which matched the previously defined biogeographical regions. This spatial structuring was also supported by microsatellite analysis, which revealed two genetically distinct populations, one in the north and one in the south.
Synthesis and applications. A multiparameter approach, combining environmental information with data on indices of density‐dependence such as jaw length, could be extremely useful for defining ecologically meaningful management units. Indeed, monitoring spatial and temporal variation in jaw length could provide deer managers with a simple way to index population structure and fluctuations in time and space.
Identification of Bacillus cereus internalin and other candidate virulence genes specifically induced during oral infection in insects
Authors: Fedhila Sinda , Daou Nadine , Lereclus Didier , Nielsen‐LeRoux Christina 
Published: September 2006

SummaryBacillus cereus is an opportunistic bacterium frequently associated with food‐borne infections causing gastroenteritis. We developed an in vivo expression technology (IVET), with an insect host, for identification of the B. cereus genes specifically expressed during infection. This IVET‐based approach uses site‐specific recombinase TnpI to identify transient promoter activation. We constructed a genomic library of B. cereus ATCC14579 by cloning DNA fragments upstream from tnpI. The library was screened in vivo by oral infection of the insect Galleria mellonella. We selected 100 clones from dead larvae. Sequencing of the inserts followed by a second screen for specific in vivo induction led to the identification of 20 in vivo‐induced genes (ivi genes). They belonged to several different functional classes: regulation, metabolism, DNA repair and replication, cell division, transport, virulence and adaptation. A strongly induced gene, ivi29, was further analysed. It encodes an internalin‐like protein with four distinct domains: an N‐terminal signal peptide for export, a NEAT domain thought to be involved in iron transport, a leucine‐rich repeat domain that may interact with host cells, and a C‐terminal SLH domain presumably binding the protein to the peptidoglycan. As suggested by a Fur box in the promoter, transcriptional analysis showed ivi29 expression to be repressed by iron, suggesting that expression was induced in vivo due to iron deprivation in the host. This iron‐regulated, leucine‐rich surface protein was designated IlsA. Disruption of ilsA reduced the virulence of the bacteria to the insect larvae indicating its role in the overall pathogenesis of B. cereus.
A novel antigen‐specific capture assay for the detection of platelet antibodies and HPA‐1a phenotyping
Authors: Meyer O. , Agaylan A. , Bombard S. , Kiesewetter H. , Salama A. 
Published: September 2006

Background and Objectives  The antigen‐specific assays currently used for the laboratory investigation of platelet antibodies and antigens are technically complex and cannot be used in most routine laboratories. Here, we describe a simple antigen‐specific capture assay (ASCA) for the detection of serum platelet antibodies and for human platelet antigen‐1a (HPA‐1a) phenotyping.Materials and Methods  For the detection of platelet antibodies, platelets from healthy blood donors were incubated with biotinylated monoclonal antibodies to platelet glycoprotein complexes (GP), then solubilized and mixed with superparamagnetic streptavidin particles. Serum samples from patients with autoimmune thrombocytopenia (n = 39), from patients with platelet alloantibodies (6 HPA‐1a, 1 HPA‐2b, 1 HPA‐3a, 6 HPA‐5b), and from healthy blood donors (n = 70), were tested. All serum samples from the patients were investigated in parallel by the indirect monoclonal antibody‐specific immobilization of platelet antigen assay (MAIPA). For HPA‐1a phenotyping, superparamagnetic particles were coated with a monoclonal antibody to HPA‐1a and mixed with diluted whole blood samples from healthy blood donors (n = 139), who had previously been genotyped for platelet alloantigens.Results  The indirect MAIPA detected autoantibodies in 18%, and the direct MAIPA in 50% of patients tested. In contrast, the new ASCA demonstrated positive results in 77% of patients. All tested alloantibodies reacted positive by the ASCA, and all serum samples from healthy blood donors were negative. The results of HPA‐1a phenotyping were in concordance with those of genotyping in all cases.Conclusion  In our opinion, the ASCA is easy to perform and much more sensitive than the currently available antigen‐specific assays for the detection of platelet antibodies.
Chemoreception and the Assessment of Fighting Abilities in the Lizard Liolaemus monticola
Authors: Labra Antonieta 
Published: September 2006

AbstractWhen an individual faces the risk of a conflict, its ability to make ‘correct’ decisions is crucial to its fitness. Research on decision making has focused mainly on visual and acoustic signals, while chemical signals have received much less attention, despite their relevance for many species. Chemosignals can be detected in the absence of the signaller and, in the context of fighting risk, this property confers the advantage that the receiver can avoid agonistic interactions or, if they are unavoidable, that it can prepare itself for the conflict. I studied the behaviour of males of the lizard Liolaemus monticola in the laboratory when they were confronted with chemosignals of a potential opponent. During this ‘pre‐confrontation’ stage, I tested the following predictions: (1) lizards can derive precise information from chemosignals of conspecifics, and use this to respond with precision to the perceived risk and (2) the best predictor of the receiver behaviour, and therefore the best predictor of the risk involved in the fight, is the relative fighting ability of opponents. As a measure of fighting ability, I used body size. ‘Intruders’ were placed in the terrarium of unfamiliar ‘residents’ during the absence of the latter, and their behaviours were recorded. Simple regressions were performed between the different behavioural variables and with the body sizes of intruder and resident, and with the relative difference in body sizes of opponents. The latter was the best predictor of intruder behaviour: it was negatively correlated with behaviours associated with activity (i.e. motion time), chemoexploration (i.e. number of tongue flicks) and behaviours associated with social interactions (i.e. head bobs). These results suggest that males can process information from chemosignals and decisions made during the ‘pre‐confrontation’ stage are based on the assessment of the relative fighting abilities (i.e. relative body size) of opponents.
Susceptibility of six pine species to Gremmeniella abietina isolates from Spain
Authors: Santamaría O. , Pando V. , Diez J. J. 
Published: September 2006

SummaryInoculation experiments were performed in order to evaluate the virulence of Gremmeniella abietina isolates from Spain on the main pine species planted in the Iberian Peninsula, as well as the influence of seedling age on this virulence. Two different experiments were carried out with four isolates of G. abietina from Spain. The greenhouse experiments consisted of seedling inoculations. One‐ and 2‐year‐old seedlings of the following five pine species were used: Pinus halepensis, Pinus pinea, Pinus pinaster, Pinus sylvestris and Pinus uncinata; also, 1‐year‐old seedlings of P. nigra were inoculated. The relative necrosis length (RNL) caused by the pathogen after 130 days was used as a response variable. The laboratory experiments were performed on 2‐ to 6‐year‐old internodes of the above pine species excluding P. uncinata. The necrosis length after 6 weeks of incubation was measured. The results have shown that all G. abietina isolates were pathogens on seedlings of these six pine species and seedlings of P. halepensis were consistently the most susceptible ones, although it is important to take into account that all the isolates used in the present work were isolated from P. halepensis, the only pine species in Spain where G. abietina has been recovered up to now. The susceptibility of the other pine species depended on the age of the seedlings.