bluuebunny/crossref_metadata_2025_split huggingface dataset:
Biogeographic barriers, connectivity and homogenization of freshwater faunas: it's a small world after all
Authors: RAHEL FRANK J. 
Published: March 2007

Summary1. Historically, biogeographic barriers to the movement of aquatic organisms existed at multiple spatial scales and contributed to the development of unique regional faunas. At increasing spatial scales, these barriers consisted of waterfalls and cascades; catchment divides; major mountain ranges and oceans. This hierarchy of movement barriers produced increasingly distinct aquatic biotas at larger drainage units.2. Humans have provided a variety of pathways by which aquatic species can circumvent historical biogeographic barriers. These include both authorised and unauthorised stocking, construction of canals and water conveyance systems, transport in ship ballast water, fishing and angling gear (including boats) transferred among water bodies and intentional release of ornamental and other captive species.3. One consequence of human‐aided breaching of biogeographic barriers has been the spread of noxious species that have altered aquatic ecosystems and fisheries in ways that are undesirable to humans.4. Another consequence of human‐aided breaching of biogeographic barriers has been the homogenization of aquatic biotas. Homogenization occurs when a few cosmopolitan species come to dominate communities at the expense of unique native species. Among aquatic organisms this phenomenon is best documented for fish faunas where a small set of species introduced for sport fishing, aquaculture, or ornamental purposes have become widespread throughout the world.5. Slowing biotic homogenization will require slowing the rate at which species breach biogeographic barriers. This will involve implementing regulations that limit stocking opportunities; increasing the public's awareness about the consequences of releasing non‐native species and developing technological solutions that prevent movement of aquatic organisms or eliminate them before they become established.6. River restoration can influence homogenization of aquatic biotas through two major mechanisms: by removing barriers to movement and by restoring natural habitat conditions. Removal of movement barriers may facilitate the spread of non‐native species and thus contribute to biotic homogenization. Restoration of natural flow regimes and habitat conditions may reduce biotic homogenization by favouring regional native species over cosmopolitan, non‐native species.
Hyporheic rehabilitation in rivers: restoring vertical connectivity
Authors: BOULTON ANDREW J. 
Published: March 2007

Summary1. The hyporheic zone below the channel and banks of many rivers where surface water and ground water exchanges plays a crucial functional role in the biogeochemical transformation of water, mediated by active microbial biofilms. This zone also harbours assemblages of invertebrates that graze biofilms, contribute to secondary production, and can alter the porosity of the hyporheic zone through their movement or burrowing activities.2. Many human activities cause interstitial sedimentation or disrupt surface–groundwater hydrological linkages, impacting upon ecological processes in the hyporheic zone. However, strategies for river rehabilitation seldom explicitly consider the hyporheic zone or seek to restore lost vertical linkages with groundwater. Instead, restoration goals target surface, riparian or floodplain features even though current river ecosystem theory emphasises the three dimensions of hydrological connectivity. To guide effective, holistic river restoration, scientists and managers therefore need information on the mechanisms by which energy and material are transferred in the hyporheic zone and which ecosystem services are thus provided.3. Other gaps in our understanding of hyporheic zone rehabilitation include recruitment processes of the hyporheos and the relative importance of groups of hyporheic invertebrates in rivers differing in substratum size, disturbance frequency and groundwater linkages. Carefully designed experiments that assess responses to hyporheic rehabilitation strategies will provide valuable data at varying scales (e.g. distribution of hyporheic habitat types at the reach scale) for management as well as providing insights into the mechanisms controlling hyporheic invertebrate assemblages and ecological processes. Fully successful river rehabilitation must include restoration of vertical linkages between the river and its shallow groundwater aquifers.
Changes in habitat structure, benthic invertebrate diversity, trout populations and ecosystem processes in restored forest streams: a boreal perspective
Authors: MUOTKA TIMO , SYRJÄNEN JUKKA 
Published: March 2007

Summary1. Most Finnish streams were channelised during the 19th and 20th century to facilitate timber floating. By the late 1970s, extensive programmes were initiated to restore these degraded streams. The responses of fish populations to restoration have been little studied, however, and monitoring of other stream biota has been negligible. In this paper, we review results from a set of studies on the effects of stream restoration on habitat structure, brown trout populations, benthic macroinvertebrates and leaf retention.2. In general, restoration greatly increased stream bed heterogeneity. The cover of mosses in channelised streams was close to that of unmodified reference sites, but after restoration moss cover declined to one‐tenth of the pre‐restoration value.3. In one stream, densities of age‐0 trout were slightly lower after restoration, but the difference to an unmodified reference stream was non‐significant, indicating no effect of restoration. In another stream, trout density increased after restoration, indicating a weakly positive response. The overall weak response of trout to habitat manipulations probably relates to the fact that restoration did not increase the amount of pools, a key winter habitat for salmonids.4. Benthic invertebrate community composition was more variable in streams restored 4–6 years before sampling than in unmodified reference streams or streams restored 8 years before sampling. Channelised streams supported a distinctive set of indicator species, most of which were filter‐feeders or scrapers, while most of the indicators in streams restored 8 years before sampling were shredders.5. Leaf retentiveness in reference streams was high, with 60–70% of experimentally released leaves being retained within 50 m. Channelised streams were poorly retentive (c. 10% of leaves retained), and the increase in retention following restoration was modest (+14% on average). Aquatic mosses were a key retentive feature in both channelised and natural streams, but their cover was drastically reduced through restoration.6. Mitigation of the detrimental impacts of forestry (e.g. removal of mature riparian forests) is a major challenge to the management of boreal streams. This goal cannot be achieved by focusing efforts only on restoration of physical structures in stream channels, but also requires conservation and ecologically sound management of riparian forests.
Attributing recovery from depression. Perceptions of people cared for in primary care
Authors: Badger Frances , Nolan Peter 
Published: March 2007

Aims and objectives.  The aim of the study was to understand how people treated for depression in primary care perceived the care they received. The focus was specifically on ascertaining their perceptions of what had helped during their treatment, their understanding of the factors to which they attributed their recovery, and their reflections on their experience of depression.Background.  Although knowledge of the factors that promote recovery from depression is growing, personal accounts of attributions of recovery are largely absent from the literature. Identifying and understanding people's accounts of their recovery is particularly important for practitioners involved in medication management and prescribing.Method.  A purposeful sample of 60 people who had accessed primary care and been prescribed medication because of depressive symptoms was interviewed using a semistructured approach. Interviews explored people's experiences of accessing and using primary care, their assessments of care offered, experiences of medication management and their attributions of recovery.Results.  Recovery from depression was characterized by its multifactorial nature, and two‐thirds of the participants felt that medication had contributed to their recovery. Factors in recovery changed with the passage of time and many perceived personal strengths as important to recovery. Practitioners who acknowledged and encouraged people's roles in recovery and supported multifaceted care were perceived by users as caring and offering holistic, individualized care.Conclusion.  People with depression are keen to regard their recovery as multifactorial and to have their own roles in recovery acknowledged. Preferences for a ‘portfolio’ of care, the components of which change as recovery progresses, were evident.Relevance to clinical practice.  Practitioners involved in prescribing and medication management for depression must aim to explore patients’ beliefs about appropriate treatments and recovery. Addressing these can potentially promote treatment concordance and enhance recovery from depression by establishing and sustaining therapeutic relationships.
Non‐finite loss and emotional labour: family caregivers’ experiences of living with motor neurone disease
Authors: Ray Robin A , Street Annette F 
Published: March 2007

Aim and objectives.  This paper aims to add to nurses’ knowledge concerning the losses and emotional labour family caregivers face caring for people living with neurodegenerative, life‐limiting illnesses such as motor neurone disease.Background.  Motor neurone disease is a relentless, progressive illness resulting in progressive loss of voluntary muscle mass and function. Previous caregiver research presents the salient losses such as social, financial and relationship loss. However, the non‐finite, unpredictable losses faced every day by caregivers and the emotional labour experienced are not effectively represented and have not been explored for caregivers of adult patients with life‐limiting, degenerative, illness.Design/methods.  Semi‐structured interviews, ecomaps of social support networks and field notes were used to collect data for this ethnographic case study. Data were attained at three time points over a 10‐month period from 18 primary caregivers and once from six peripheral caregivers.Results.  Data revealed new information about the psychosocial and emotional losses experienced daily, when living with motor neurone disease. The impact of the constancy of voluntary muscle degeneration and the uncertainty of the illness progression in terms of available time and functional loss, threatened people's understanding and expectations of life, their relationships, their personal identity and their future. Managing their relationship with the patient and their reactions to the devastation of motor neurone disease is consistent with the concept of emotional labour.Conclusions.  Family caregivers living with relentless, life‐limiting illness experience non‐finite losses and emotional labour on a daily basis. While each individual's experience of loss is unique, nurses need to include caregivers as well as patients, in their spectrum of supportive care.Relevance to clinical practice.  Nurses can be independent confidants who share the emotional labour and work with caregivers to develop interventions to assist them to manage their losses and their changing needs for psychological and emotional support.
The process of developing audiovisual patient information: challenges and opportunities
Authors: Hutchison Catherine , McCreaddie May 
Published: March 2007

Aim.  The aim of this project was to produce audiovisual patient information, which was user friendly and fit for purpose. The purpose of the audiovisual patient information is to inform patients about randomized controlled trials, as a supplement to their trial‐specific written information sheet.Background.  Audiovisual patient information is known to be an effective way of informing patients about treatment. User involvement is also recognized as being important in the development of service provision. The aim of this paper is (i) to describe and discuss the process of developing the audiovisual patient information and (ii) to highlight the challenges and opportunities, thereby identifying implications for practice. A future study will test the effectiveness of the audiovisual patient information in the cancer clinical trial setting.Methods.  An advisory group was set up to oversee the project and provide guidance in relation to information content, level and delivery. An expert panel of two patients provided additional guidance and a dedicated operational team dealt with the logistics of the project including: ethics; finance; scriptwriting; filming; editing and intellectual property rights.Results.  Challenges included the limitations of filming in a busy clinical environment, restricted technical and financial resources, ethical needs and issues around copyright. There were, however, substantial opportunities that included utilizing creative skills, meaningfully involving patients, teamworking and mutual appreciation of clinical, multidisciplinary and technical expertise.Conclusion.  Developing audiovisual patient information is an important area for nurses to be involved with. However, this must be performed within the context of the multiprofessional team. Teamworking, including patient involvement, is crucial as a wide variety of expertise is required.Relevance to clinical practice.  Many aspects of the process are transferable and will provide information and guidance for nurses, regardless of specialty, considering developing this format of patient information.
A new individual‐based spatial approach for identifying genetic discontinuities in natural populations
Authors: MANEL S. , BERTHOUD F. , BELLEMAIN E. , GAUDEUL M. , LUIKART G. , SWENSON J. E. , WAITS L. P. , TABERLET P. , CONSORTIUM INTRABIODIV 
Published: March 2007

AbstractThe population concept is central in evolutionary and conservation biology, but identifying the boundaries of natural populations is often challenging. Here, we present a new approach for assessing spatial genetic structure without thea prioriassumptions on the locations of populations made by adopting an individual‐centred approach. Our method is based on assignment tests applied in a moving window over an extensively sampled study area. For each individual, a spatially explicit probability surface is constructed, showing the estimated probability of finding its multilocus genotype across the landscape, and identifying putative migrants. Population boundaries are localized by estimating the mean slope of these probability surfaces over all individuals to identify areas with genetic discontinuities. The significance of the genetic discontinuities is assessed by permutation tests. This new approach has the potential to reveal cryptic population structure and to improve our ability to understand gene flow dynamics across landscapes. We illustrate our approach by simulations and by analysing two empirical datasets: microsatellite data ofUrsus arctosin Scandinavia, and amplified fragment length polymorphism (AFLP) data ofRhododendron ferrugineumin the Alps.
Host–parasite kinship in a female‐philopatric bird population: evidence from relatedness trend analysis
Authors: ANDERSSON MALTE , WALDECK PETER 
Published: March 2007

AbstractConspecific brood parasitism (CBP), an alternative reproductive tactic where some females lay eggs in the nests of other females of the same species, occurs in many animals with egg care. It is particularly common in waterfowl, for reasons that are debated. Many waterfowl females nest near their birthplace, making it likely that some local females are relatives. We analyse brood parasitism in a Hudson Bay population of common eiders, testing predictions from two alternative hypotheses on the role of relatedness in CBP. Some models predict host–parasite relatedness, others predict that parasites avoid close relatives as hosts. To distinguish between the alternatives, we use a novel approach, where the relatedness of host–parasite pairs is tested against the spatial population trend in pairwise relatedness. We estimate parasitism, nest take‐over and relatedness with protein fingerprinting and bandsharing analysis of egg albumen, nondestructively sampled from each new egg in the nest throughout the laying period. The results refute the hypothesis that parasites avoid laying eggs in the nests of related hosts, and corroborate the alternative of host–parasite relatedness. With an estimated r of 0.12–0.14, females laying eggs in the same nest are on average closer kin than nesting neighbour females. Absence of a population trend in female pairwise relatedness vs. distance implies that host–parasite relatedness is not only an effect of strong natal philopatry: some additional form of kin bias is also involved.
Trade‐off between root porosity and mechanical strength in species with different types of aerenchyma
Authors: STRIKER G. G. , INSAUSTI P. , GRIMOLDI A. A. , VEGA A. S. 
Published: March 2007

ABSTRACTThe objective of this work was to study the existence of a trade‐off between aerenchyma formation and root mechanical strength. To this end, relationships among root anatomical traits and mechanical properties were analysed in plant species with contrasting root structural types: Paspalidium geminatum (graminaceous type), Cyperus eragrostis (cyperaceous type), Rumex crispus (Rumex type) and Plantago lanceolata (Apium type). Variations in anatomical traits and mechanical strength were assessed as a function of root diameter by exposing plants to 0, 7, 15 and 30 d of control and flooded conditions. For each species, the proportion of root cortex was positively associated with the increment of root diameter, contributing to the increase in root porosity under both control and flooded conditions. Moreover, cell lysis produced an additional increase in root porosity in most species under flooded conditions (except R. crispus). Both structural types that presented a uniseriate layer (epidermis) to cope with compression (Rumex and Apium types) were progressively weakened as root porosity increased. This effect was significant even when the increment of root porosity was solely because of increased root diameter (R. crispus), as when both processes (root diameter and cell lysis) added porosity to the roots (P. lanceolata). Conversely, structural types that presented a multiseriate ring of cells in the outer cortex (graminaceous and cyperaceous types) maintained mechanical strength over the whole range of porosity, in spite of lysogenic processes registered in the inner cortex. In conclusion, our study demonstrates a strong trade‐off between aerenchyma formation and mechanical strength in root structural types that lacked a multiseriate ring of tissue for mechanical protection in the outer cortex. The results suggest that this ring of tissue plays a significant role in maintaining the mechanical strength of roots when flooding induces the generation of additional aerenchyma tissue in the root cortex.
Isoprene synthase expression and protein levels are reduced under elevated O3 but not under elevated CO2 (FACE) in field‐grown aspen trees
Authors: CALFAPIETRA CARLO , WIBERLEY AMY E. , FALBEL TANYA G. , LINSKEY AUTUMN R. , MUGNOZZA GIUSEPPE SCARASCIA , KARNOSKY DAVID F. , LORETO FRANCESCO , SHARKEY THOMAS D. 
Published: March 2007

ABSTRACTEmission of hydrocarbons by trees has a crucial role in the oxidizing potential of the atmosphere. In particular, isoprene oxidation leads to the formation of tropospheric ozone and other secondary pollutants. It is expected that changes in the composition of the atmosphere will influence the emission rate of isoprene, which may in turn feedback on the accumulation of pollutants and greenhouse gases. We investigated the isoprene synthase (ISPS) gene expression and the ISPS protein levels in aspen trees exposed to elevated ozone (O3) and/or elevated carbon dioxide (CO2) in field‐grown trees at the Aspen Free‐Air Carbon Dioxide Enrichment (FACE) experimental site. Elevated O3 reduced ISPS mRNA and the amount of ISPS protein in aspen leaves, whereas elevated CO2 had no significant effect. Aspen clones with different O3 sensitivity showed different levels of inhibition under elevated O3 conditions. The drop in ISPS protein levels induced a drop in the isoprene emission rate under elevated O3. However, the data indicated that other mechanisms also contributed to the observed strong inhibition of isoprene emission under elevated O3.
Characterization and expression analysis of genes encoding α and β carbonic anhydrases in Arabidopsis
Authors: FABRE NICOLAS , REITER ILJA M , BECUWE‐LINKA NOELLE , GENTY BERNARD , RUMEAU DOMINIQUE 
Published: March 2007

ABSTRACTCarbonic anhydrases (CAs) are Zn‐containing metalloenzymes that catalyse the reversible hydration of CO2. We investigated the αCA and βCA families in Arabidopsis, which contain eight αCA (AtαCA1‐8) and six βCA genes (AtβCA1‐6). Analyses of expressed sequence tags (ESTs) from The Arabidopsis Information Resource (TAIR) database indicate that all the βCA encoding sequences, but only three of the AtαCA, are expressed. Using semi‐quantitative PCR experiments, functional CA genes were more strongly expressed in green tissue, but strong expression was also found in roots for βCA3, βCA6 and αCA2. Two αCA genes were shown to respond to the CO2 environment, while the others were unresponsive. Using the green fluorescent reporter protein gene fused with cDNA sequences coding for βCAs, we provided evidence that βCAs were targeted to specific subcellular compartments: βCA1 and βCA5 were targeted to the chloroplast, βCA2 and βCA3 to the cytosol, βCA4 to the plasma membrane and βCA6 to the mitochondria. The targeting and the pattern of gene expression suggest that CA isoforms play specific roles in subcellular compartments, tissues and organs. The data indicate that other CA isoforms than the well‐characterized βCA1 may contribute to the CO2 transfer in the cell to the catalytic site of ribulose 1·5‐bisphosphate carboxylase/oxygenase (Rubisco).