bluuebunny/crossref_metadata_2025_split huggingface dataset:
THE TROPHIC ECOLOGY OF FRESHWATER GAMMARUS SPP. (CRUSTACEA:AMPHIPODA): PROBLEMS AND PERSPECTIVES CONCERNING THE FUNCTIONAL FEEDING GROUP CONCEPT
Authors: MACNEIL CALUM , DICK JAIMIE T. A. , ELWOOD ROBERT W. 
Published: August 2010

ABSTRACT Gammarus spp. are widespread throughout a diverse range of freshwater habitats and can be the dominant part of many benthic macroinvertebrate assemblages, in terms of both numbers and/or biomass. Although the vast majority of studies have emphasized the herbivorous nature of Gammarus spp. and their ‘shredder’ functional feeding group (FFG) classification, we show that a far wider food base is exploited than has been previously acknowledged. This ‘plasticity’ as herbivore/predator is linked to the success of Gammarus spp. in persisting in and colonizing/invading disturbance‐prone ecosystems. Intraguild predation and cannibalism are more common than previously realized. This behaviour appears to be a causal mechanism in many amphipod species replacements. Additionally, Gammarus spp. are major predators of other members of the macroinvertebrate community. Furthermore, while many studies have emphasized fish predation on Gammarus spp., we illustrate how this fish: amphipod, predator: prey interaction may be a two‐way process, with Gammarus spp. themselves preying upon juvenile and wounded/trapped fish. We urge that a new realism be adopted towards the trophic ecology of Gammarus spp. and their role as predators and prey and that previously established FFG assumptions of both the food and the feeder be questioned critically.
The origin and early evolution of birds
Authors: PADIAN KEVIN , CHIAPPE LUIS M. 
Published: August 2010

ABSTRACTBirds evolved from and are phylogenetically recognized as members of the theropod dinosaurs; their first known member is the Late Jurassic Archaeopteryx, now represented by seven skeletons and a feather, and their closest known non‐avian relatives are the dromaeosaurid theropods such as Deinonychus. Bird flight is widely thought to have evolved from the trees down, but Archaeopteryx and its outgroups show no obvious arboreal or tree‐climbing characters, and its wing planform and wing loading do not resemble those of gliders. The ancestors of birds were bipedal, terrestrial, agile, cursorial and carnivorous or omnivorous. Apart from a perching foot and some skeletal fusions, a great many characters that are usually considered ‘avian’ (e.g. the furcula, the elongated forearm, the laterally flexing wrist and apparently feathers) evolved in non‐avian theropods for reasons unrelated to birds or to flight. Soon after Archaeopteryx, avian features such as the pygostyle, fusion of the carpometacarpus, and elongated curved pedal claws with a reversed, fully descended and opposable hallux, indicate improved flying ability and arboreal habits. In the further evolution of birds, characters related to the flight apparatus phylogenetically preceded those related to the rest of the skeleton and skull. Mesozoic birds are more diverse and numerous than thought previously and the most diverse known group of Cretaceous birds, the Enantiornithes, was not even recognized until 1981. The vast majority of Mesozoic bird groups have no Tertiary records: Enantiornithes, Hesperornithiformes, Ichthyornithiformes and several other lineages disappeared by the end of the Cretaceous. By that time, a few Linnean ‘Orders’ of extant birds had appeared, but none of these taxa belongs to extant ‘families’, and it is not until the Paleocene or (in most cases) the Eocene that the majority of extant bird ‘Orders’ are known in the fossil record. There is no evidence for a major or mass extinction of birds at the end of the Cretaceous, nor for a sudden ‘bottleneck’ in diversity that fostered the early Tertiary origination of living bird ‘Orders’.
Labile sex expression in plants
Authors: KORPELAINEN HELENA 
Published: August 2010

ABSTRACTThe range of environmental sex determination and sex changes throughout plant taxa from bryophytes and pteridophytes to spermatophytes is reviewed. Lability in sex expression occurs in many plant taxa but only in homosporous pteridophytes is labile sex the rule. Among angiosperms, labile sex appears to be more common among dioecious and monoecious plants than among hermaphrodites. However, hermaphrodites can control allocation to male and female functions by varying the relative emphasis on pollen and ovules. A majority of plants with labile sex expression are perennials, which indicates that flexibility in sex is more important for species with long life cycles. Environmental stress, caused by less‐than‐optimal light, nutrition, weather or water conditions, often favours maleness. The extreme lability in the sex expression of homosporous pteridophytes is suggested to be related primarily to the mating systems.
The selection, testing and application of terrestrial insects as bioindicators
Authors: McGEOGH MELODIE A. 
Published: August 2010

ABSTRACTAlthough the uses and merits of terrestrial insects as indicators have been extensively discussed, there is a lack of clear definition, goal directedness and hypothesis testing in studies in the field. In an attempt to redress some of these issues and outline an approach for further studies, three categories of terrestrial insect indicators, corresponding to differences in their application, are proposed, i.e. environmental, ecological and biodiversity indicators. The procedures in terrestrial insect bioindicator studies should start with a clear definition of the study objectives and proposed use of the bioindicator, as well as with a consideration of the scale at which the study is to be carried out. Bioindication studies are conducted at a variety of spatial and temporal scales within the context of earth‐system processes, but the objectives of the study will largely determine the scale at which it would be optimally conducted. There is a tendency for studies to be conducted below their space‐time scaling functions, giving them apparent predictability. The selection of potential indicator taxa or groups is then based ona priorisuitability criteria, the identification of predictive relationships between the indicator and environmental variables and, most importantly, the development and testing of hypotheses according to the correlative patterns found. Finally, recommendations for the use of the indicator in monitoring should be made. Although advocating rigorous, long‐term protocols to identify indicators may presently be questionable in the face of the urgency with which conservation decisions have to be made, this approach is critical if bioindicators are to be used with any measurable degree of confidence.
The braincase ofEuparkeria, and the evolutionary relationships of birds and crocodilians
Authors: GOWER DAVID J. , WEBER ERICH 
Published: August 2010

ABSTRACTThe Triassic reptileEuparkeriahas been frequently given a pivotal position in interpretations of the evolution of archosaurs. Most recently, Welman (1995) has argued from braincase data thatEuparkeriais more closely related to birds than are either theropod dinosaurs or crocodilians – a conclusion clearly at odds with the current orthodoxy. The braincase of a single specimen ofEuparkeriais described in detail and compared with previous descriptions and with the braincases of other diapsids. Variations among the known specimens are documented. The homology of various braincase structures are reassessed in light of the study by Welman (1995). We argue that the braincase ofEuparkeriahas an undivided metotic fissure, an incompletely ossified medial wall of the otic capsule, a well‐defined ‘semilunar depression’, and posteroventrally positioned foramina in the parabasisphenoid for the entrance of the cerebral branches of the internal carotid arteries. It lacks enclosure of the Eustachian system in bone, well‐developed tympanic sinuses, or a well‐defined recess for the lagena. A review of braincase morphology in extinct and extant diapsids suggests that braincase features ofEuparkeriaare largely plesiomorphic for Archosauria. The evolutionary relationships betweenEuparkeriaand extant archosaurs (birds and crocodilians) are considered by reviewing braincase morphology in extant and extinct diapsids. No shared derived characters could be found that support the resolutions (crocodilians (Euparkeria+ birds)) or (birds (Euparkeria+ crocodilians)). Three derived characters shared by extant archosaurs support the resolution (Euparkeria(crocodilians + birds)), but only the presence of laterally positioned foramina in the parabasisphenoid for the entrance of the cerebral branches of the internal carotid arteries appears to represent strong evidence. The other two features are a degree of ossification (of the medial wall of the otic capsule) that exhibits some homoplasy among archosaurs, and an absence (of the ‘semilunar depression’), and therefore do not represent particularly robust hypotheses of homology. Our interpretation of the braincase ofEuparkeriais fully congruent with the consensus among recent explicit phylogenetic analyses that this taxon is close to, but not a member of, the archosaur crown group. Birds and crocodilians share a number of other derived similarities (subdivided metotic fissure, elongated and tubular cochlear recess, enclosed Eustachian system, extensive tympanic sinuses, quadrate‐prootic articulation) that are probably not homologous because of their absence in a number of non‐avian dinosaurs and crocodilian‐line crown‐group archosaurs.
What and how do maggots smell?
Authors: COBB MATTHEW 
Published: August 2010

ABSTRACTThe olfactory response of maggots (the larvae of cyclorrhaphous flies) and its neuroanatomical basis have been a subject for scientific investigation since the 17th century, preoccupying both fundamental and applied scientists. Despite its apparently arcane nature, the subject raises a series of major neurobiological problems, in particular, the relationship between the number of odours that can be detected and the apparently simple systems of detection and processing available to larvae. Molecular biological techniques in both neuroanatomy and cell biology have made it possible to begin to resolve some of these problems, if data from a wide range of studies are integrated. Four sectors of research on a large number of species are reviewed: the behaviour involved in the olfactory response, the wide range of odours that can be detected, the neuroanatomical basis of olfaction in cyclorrhaphous larvae and the number of receptors involved in detecting these odours. Finally, a neuroanatomical model of olfactory processing is presented, together with perspectives for future research, emphasising the importance of studying the ecology of the species under investigation.
The behavioural ecology of mixed‐species troops of callitrichine primates
Authors: HEYMANN ECKHARD W. , BUCHANAN‐SMITH HANNAH M. 
Published: August 2010

ABSTRACTThis review summarizes information on the behavioural ecology of mixed‐species troops (interspecific associations) formed by different species of callitrichines, small New World monkeys, in western and central Amazonia. The formation of mixed‐species troops is an integral part of the biology of several species of this subfamily. Niche separation between associated species is obtained through vertical segregation which results in differences in the prey spectrum. The degree of niche separation is a predictor for the stability of mixedspecies troops. Individuals may benefit from the formation of mixed‐species troops through increased safety from predators, increased foraging effciency, and or increased resource defence. Costs of mixed‐species troop formation are probably very low and mainly relate to patterns of interspecific behavioural interactions. We point to gaps in our knowledge and suggest pathways for future research into mixed‐species troops.
Aphid saliva
Authors: MILES PETER W. 
Published: August 2010

ABSTRACTWithin the Aphidoidea, most species of Aphididae, as long as they are in small numbers and not carrying plant viruses, do little perceptible damage to their food plants. In species that cause toxicoses, it is usually assumed that some component of the saliva must be responsible. Paradoxically, however, the salivary enzymes of Aphididae are similar to those that already occur in plants – oxidases and enzymes that depolymerize polysaccharides – and the salivary enzymes are injected in very small amounts relative to their counterparts in the plant. Damage to plants triggers defensive, biochemical responses, and it is suggested that the injected enzymes serve mainly to divert or counter responses at the immediate interface of stylets and plant tissues. The saliva of Aphididae contains non‐enzymic, reducing compounds which, in the presence of oxidases, can combine with and inactivate defensive phytochemicals – including those released in response to damage and transported in the phloem sieve tube sap on which Aphididae feed. Salivary and gut oxidases deactivate ingested phytochemicals by oxidative polymerization. Aphididae inject saliva into sieve tubes before sustained ingestion of sap, and this saliva has been presumed to condition the sieve tubes, but in what way remains unclear. It is suggested that there is a dynamic biochemical interaction between aphids and plants; that the interaction is usually well balanced for most of the Aphididae; hence, no outcome is readily observable. Where a significant imbalance occurs, however, either the aphid is unable to feed, i.e. the plant is resistant, and/or the aphid does not effectively counter a hypersensitive response. Not all plant responses are disadvantageous to aphids. Gall‐forming Aphidoidea trigger and control abnormal growth in the plant to the insects' advantage, possibly by eliciting vigorous oxidation in selective meristematic tissues, thereby limiting supply of molecular oxygen and inhibiting oxygen‐dependent growth‐controls. Current problems and possible approaches for further research are reviewed.
Stems, nodes, crown clades, and rank‐free lists: is Linnaeus dead?
Authors: BENTON MICHAEL J. 
Published: August 2010

ABSTRACTRecent radical proposals to overhaul the methods of biological classification are reviewed. The proposals of phylogenetic nomenclature are to translate cladistic phylogenies directly into classifications, and to define taxon names in terms of clades. The method has a number of radical consequences for biologists: taxon names must depend rigidly on the particular cladogram favoured at the moment, familiar names may be reassigned to unfamiliar groupings, Linnaean category terms (e.g. phylum, order, family) are abandoned, and the Linnaean binomen (e.g.Homo sapiens) is abandoned. The tenets of phylogenetic nomenclature have gained strong support among some vocal theoreticians, and rigid principles for legislative control of clade names and definitions have been outlined in the PhyloCode. The consequences of this semantic maelstrom have not been worked out. In practice, phylogenetic nomenclature will be disastrous, promoting confusion and instability, and it should be abandoned. It is based on a fundamental misunderstanding of the difference between a phylogeny(which is real) and a classification (which is utilitarian). Under the new view, classifications are identical to phylogenies, and so the proponents of phylogenetic nomenclature will end up abandoning classifications altogether.
Delivery outcome of women with epilepsy:a population‐based cohort study
Authors: Borthen I , Eide MG , Daltveit AK , Gilhus NE 
Published: August 2010

Please cite this paper as: Borthen I, Eide M, Daltveit A, Gilhus N. Delivery outcome of women with epilepsy: a population‐based cohort study. BJOG 2010;117:1537–1543.Objective  To investigate whether women with epilepsy have increased risks of complications during labour, and to explore the impact of antiepileptic drug use.Design  Population‐based cohort study.Setting  Data from the Medical Birth Registry of Norway 1999–2005.Population  All births (n = 372 128) delivered in Norway, ensured through linkage with the National Population Registry run by Statistics Norway. All singleton births and the first child in multiple pregnancies were included, leaving 365 107 pregnancies for analysis.Methods  Data from the Medical Birth Registry of Norway 1999–2005 were analysed.Main outcome measures  Induction, caesarean section, use of forceps and vacuum, abnormal presentation, placental abruption, mechanical disproportion, postpartum haemorrhage, atony and Apgar score < 7 after 5 minutes.Results  We compared 2805 pregnancies in women with a current or past history of epilepsy (0.8%) and 362 302 pregnancies in women without a history of epilepsy. Antiepileptic drugs were used in 33.6% (n = 942) of pregnant women with epilepsy. Women with epilepsy had an increased risk of induction [odds ratio (OR), 1.3; 95% confidence interval (CI), 1.1–1.4], caesarean section (OR, 1.4; 95% CI, 1.3–1.6) and postpartum haemorrhage (OR, 1.2; 95% CI, 1.1–1.4) compared with women without epilepsy. These rates were even higher for women with epilepsy and antiepileptic drug use, with ORs (95% CIs) of 1.6 (1.4–1.9), 1.6 (1.4–1.9) and 1.5 (1.3–1.9), respectively. In addition, the risk of an Apgar score < 7 was higher (OR, 1.6; 95% CI, 1.1–2.4). For women with epilepsy without antiepileptic drug use, only a slightly increased risk of caesarean delivery was observed and no increased risk for any other complications studied.Conclusions  Pregnant women with epilepsy have a low complication rate; however, they have a slightly increased risk of induction, caesarean section and postpartum haemorrhage. It is not possible to ascertain on the basis of this study whether this is a result of more severe epilepsy or antiepileptic drug use.
The impact of information skills training on independent literature searching activity and requests for mediated literature searches
Authors: Addison John , Glover Steven William , Thornton Christine 
Published: August 2010

AbstractBackground:  Most NHS library services routinely offer both mediated searches and information skills training sessions to their users. We analyse the impact of these two services on the amount of literature searching demonstrated by users of hospital‐ based library services in the north‐west of England.Methods:  Data for (1) mediated literature searches, (2) number of library users attending information skills training sessions, (3) amount of library staff time devoted to information skills training, and (4) number of Athens‐authenticated log‐ins to databases were obtained from statistical returns for 2007, and analysed for significant correlations.Results:  There was evidence of quite strong correlations between the two measures of training activity and the number of mediated literature searches performed by library staff. There was weaker evidence of correlation between training activity and total literature searching activity.Discussion:  Attending training sessions may make some library users aware of the difficulty of complex literature searches and actually reduce their confidence to perform their own complex searches independently. The relationships between information skills training, mediated literature searches, and independent literature searching activity remain complex.
Key words and their role in information retrieval
Authors: Grant Maria J. 
Published: August 2010

AbstractAs any good library or information worker knows the accurate and consistent application of keywords can serve to enhance the content representation and retrieval of literature. Research has demonstrated that this aspect of the library and information science evidence base is particularly well represented. Drawing on the thesauri of the Library & Science Abstracts, Library, Information Science & Technology Abstracts and medline databases, the Health Information and Libraries Journal (HILJ) has recently updated and expanded the HILJ keyword list. Based on the content of reviews and original articles published in HILJ over the past 4 years, the keyword list will be used by submitting authors to represent the content of the manuscripts and enable more accurate matching of manuscript to HILJ referees.
An experimental and theoretical approach to determining linkages between geochemical variability and microbial biodiversity in seafloor hydrothermal chimneys
Authors: HOUGHTON J. L. , SEYFRIED JR W. E. 
Published: August 2010

AbstractNew experimental results of fluid–mineral reactions at hydrothermal conditions relevant to life demonstrate that key redox reactions involving iron, sulfur, and hydrogen remain at disequilibrium at 100 °C, even in a heterogeneous system and thus are energetically favorable for microbial metabolism. Predictions from geochemical models utilizing the experimental results and specific to two contrasting case studies from the East Pacific Rise were statistically characterized and correlated to the energetics of redox reactions available for intra‐chimney microbial populations. In general, predictions of available energy for autotrophic metabolism are largely similar between the mature and the nascent chimneys, although important differences still exist. Metabolic processes predicted by energetics exhibit the same trends observed in the field data for the mature chimney, but overestimate the diversity observed in the nascent chimney. Several combinations of redox reaction pairs are predicted to support mixed consortia, while some combinations appear to favor more versatile microbes capable of utilizing several reactions under rapidly changing environmental conditions within chimney walls. In addition, conditions favorable to elemental sulfur reduction and methanogenesis exhibit a negative control on the diversity of microbial populations within these chimney walls, whereas H2S oxidation, elemental sulfur oxidation and the knallgas reaction are positively correlated with both abundance and diversity of micro‐organisms. Coupling field observations of both microbial diversity and geochemical heterogeneity with lab‐based experimental and theoretical modeling can facilitate translation of the observed genetic diversity into physiological diversity, thus enhancing understanding of linked phenomena of microbially induced biogeochemical transformations in complex heterogeneous systems.
Solving diameter‐constrained minimum spanning tree problems by constraint programming
Authors: Noronha Thiago F. , Ribeiro Celso C. , Santos Andréa C. 
Published: August 2010

AbstractThe diameter‐constrained minimum spanning tree problem consists in finding a minimum spanning tree of a given graph, subject to the constraint that the maximum number of edges between any two vertices in the tree is bounded from above by a given constant. This problem typically models network design applications where all vertices communicate with each other at a minimum cost, subject to a given quality requirement. We propose alternative formulations using constraint programming that circumvent weak lower bounds yielded by most mixed‐integer programming formulations. Computational results show that the proposed formulation, combined with an appropriate search procedure, solves larger instances and is faster than other approaches in the literature.