bluuebunny/crossref_metadata_2025_split huggingface dataset:
The pink shrimp Farfantepenaeus duorarum, its symbionts and helminths as bioindicators of chemical pollution in Campeche Sound, Mexico
Authors: Vidal-Martínez V.M. , Aguirre-Macedo M.L. , Del Rio-Rodríguez R. , Gold-Bouchot G. , Rendón-von Osten J. , Miranda-Rosas G.A. 
Published: June 2006

AbstractThe pink shrimp Farfantepenaeus duorarum may acquire pollutants, helminths and symbionts from their environment. Statistical associations were studied between the symbionts and helminths of F. duorarum and pollutants in sediments, water and shrimps in Campeche Sound, Mexico. The study area spatially overlapped between offshore oil platforms and natural shrimp mating grounds. Spatial autocorrelation of data was controlled with spatial analysis using distance indices (SADIE) which identifies parasite or pollutant patches (high levels) and gaps (low levels), expressing them as clustering indices compared at each point to produce a measure of spatial association. Symbionts included the peritrich ciliates Epistylis sp. and Zoothamnium penaei and all symbionts were pooled. Helminths included Hysterothylacium sp., Opecoeloides fimbriatus, Prochristianella penaei and an unidentified cestode. Thirty-five pollutants were identified, including polycyclic aromatic hydrocarbons (PAHs), polychlorinated biphenyls (PCBs), pesticides and heavy metals. The PAHs (2–3 ring) in water, unresolved complex mixture (UCM), Ni and V in sediments, and Zn, Cr and heptachlor in shrimps were significantly clustered. The remaining pollutants were randomly distributed in the study area. Juvenile shrimps acquired pesticides, PAHs (2–3 rings) and Zn, while adults acquired PAHs (4–5 rings), Cu and V. Results suggest natural PAH spillovers, and continental runoff of dichlorodiphenyltrichloroethane (DDT), PCBs and PAHs (2–3 ring). There were no significant associations between pollutants and helminths. However, there were significant negative associations of pesticides, UCM and PCBs with symbiont numbers after controlling shrimp size and spatial autocorrelation. Shrimps and their symbionts appear to be promising bioindicators of organic chemical pollution in Campeche Sound.
Serum ghrelin levels are suppressed in hypopituitary patients following insulin‐induced hypoglycaemia irrespective of GH status
Authors: Ryber Louise , Öbrink Kristina , Houe Nanna , Frystyk Jan , Jørgensen Jens Otto Lunde 
Published: June 2006

SummaryObjective  Circulating ghrelin is suppressed during insulin‐induced hypoglycaemia in healthy subjects, but it is unknown whether this is determined by feedback inhibition from counter‐regulatory hormones. We therefore investigated the impact of GH and cortisol on ghrelin secretion during insulin‐induced hypoglycaemia.Design  Serum levels of ghrelin, GH, and cortisol were measured in 41 adult patients with suspected hypopituitarism during insulin‐induced hypoglycaemia. Based on their peak GH response (cut‐off level: 3 µg/l), the patients were divided into a GH‐sufficient group (GHS) and a GH‐deficient group (GHD).Results  The GHS patients (n = 16) were younger (P < 0·01), had lower baseline cortisol levels [255 ± 37 vs. 372 ± 38 nmol/l (P = 0·04)], and tended to have a lower body mass index (P = 0·09) as compared to GHD patients (n = 25). By definition, peak GH (µg/l) was higher in GHS patients [15·0 ± 1·8 vs. 1·0 ± 0·2 (P < 0·0001)].The increase in serum cortisol during the ITT (insulin‐tolerance test) was higher and occurred later in GHS patients [Cmax (nmol/l): 561 ± 41 vs. 412 ± 50 (P = 0·04); Tmax (minutes): 65 ± 5 vs. 49 ± 5 (P = 0·03)]. Serum ghrelin levels changed significantly with time during ITT in both groups (P < 0·0001), characterized by a moderate decline during the initial 50–60 min and a return to baseline after 2 h. No significant differences were recorded in AUCghrelin during the ITT between the two groups. No gender differences in ghrelin levels were recorded.Conclusions  (i) Like in healthy subjects serum ghrelin levels are suppressed during an ITT in patients with suspected hypopituitarism. (ii) The suppression of ghrelin was similar in GHD and GHS subjects and was not determined by cortisol. (iii) We hypothesize that insulin rather than hypoglycaemia accounts for ghrelin suppression during an ITT.
Synergistic effects associated with climate change and the development of rocky shore molluscs
Authors: Przeslawski R. , Davis A. R. , Benkendorff K. 
Published: June 2006

AbstractGlobal climate change and ozone layer thinning will simultaneously expose organisms to increasingly stressful conditions. Early life stages of marine organisms, particularly eggs and larvae, are considered most vulnerable to environmental extremes. Here, we exposed encapsulated embryos of three common rocky shore gastropods to simultaneous combinations of ecologically realistic levels of ultraviolet radiation (UVR), water temperature stress and salinity stress to identify potential interactions and associated impacts of climate change. We detected synergistic effects with increases in mortality and retardation in development associated with the most physiologically stressful conditions. The effects of UVR were particularly marked, with mortality increasing up to 12‐fold under stressful conditions. Importantly, the complex outcomes observed on applying multiple stressors could not have been predicted from examining environmental variables in isolation. Hence, we are probably dramatically underestimating the ecological impacts of climate change by failing to consider the complex interplay of combinations of environmental variables with organisms.
Fire history and the global carbon budget: a 1°× 1° fire history reconstruction for the 20th century
Authors: Mouillot Florent , Field Christopher B. 
Published: June 2006

AbstractA yearly global fire history is a prerequisite for quantifying the contribution of previous fires to the past and present global carbon budget. Vegetation fires can have both direct (combustion) and long‐term indirect effects on the carbon cycle. Every fire influences the ecosystem carbon budget for many years, as a consequence of internal reorganization, decomposition of dead biomass, and regrowth. We used a two‐step process to estimate these effects. First we synthesized the available data available for the 1980s or 1990s to produce a global fire map. For regions with no data, we developed estimates based on vegetation type and history. Second, we then worked backwards to reconstruct the fire history. This reconstruction was based on published data when available. Where it was not, we extrapolated from land use practices, qualitative reports and local studies, such as tree ring analysis. The resulting product is intended as a first approximation for questions about consequences of historical changes in fire for the global carbon budget. We estimate that an average of 608 Mha yr−1burned (not including agricultural fires) at the end of the 20th century. 86% of this occurred in tropical savannas. Fires in forests with higher carbon stocks consumed 70.7 Mha yr−1at the beginning of the century, mostly in the boreal and temperate forests of the Northern Hemisphere. This decreased to 15.2 Mha yr−1in the 1960s as a consequence of fire suppression policies and the development of efficient fire fighting equipment. Since then, fires in temperate and boreal forests have decreased to 11.2 Mha yr−1. At the same time, burned areas increased exponentially in tropical forests, reaching 54 Mha yr−1in the 1990s, reflecting the use of fire in deforestation for expansion of agriculture. There is some evidence for an increase in area burned in temperate and boreal forests in the closing years of the 20th century.
Foliar respiration acclimation to temperature and temperature variableQ10alter ecosystem carbon balance
Authors: Wythers Kirk R. , Reich Peter B. , Tjoelker Mark G. , Bolstad Paul B. 
Published: June 2006

AbstractThe response of respiration to temperature in plants can be considered at both short‐ and long‐term temporal scales. Short‐term temperature responses are not well described by a constantQ10of respiration, and longer‐term responses often include acclimation. Despite this, many carbon balance models use a staticQ10of respiration to describe the short‐term temperature response and ignore temperature acclimation.We replaced static respiration parameters in the ecosystem model photosynthesis and evapo‐transpiration (PnET) with a temperature‐driven basal respiration algorithm (Rdacclim) that accounts for temperature acclimation, and a temperature‐variableQ10algorithm (Q10var). We ran PnET with the new algorithms individually and in combination for 5 years across a range of sites and vegetation types in order to examine the new algorithms' effects on modeled rates of mass‐ and area‐based foliar dark respiration, above ground net primary production (ANPP), and foliar respiration–photosynthesis ratios.TheRdacclimalgorithm adjusted dark respiration downwards at temperatures above 18°C, and adjusted rates up at temperatures below 5°C. TheQ10varalgorithm adjusted dark respiration down at temperatures below 15°C. Using both algorithms simultaneously resulted in decreases in predicted annual foliar respiration that ranged from 31% at a tall‐grass prairie site to 41% at a boreal coniferous site. The use of theRdacclimandQ10varalgorithms resulted in increases in predicted ANPP ranging from 18% at the tall‐grass prairie site to 38% at a warm temperate hardwood forest site.The new foliar respiration algorithms resulted in substantial and variable effects on PnETs predicted estimates of C exchange and production in plants and ecosystems. Current models that use static parameters may over‐predict respiration and subsequently under‐predict and/or inappropriately allocate productivity estimates. Incorporating acclimation of basal respiration and temperature‐sensitiveQ10have the potential to enhance the application of ecosystem models across broad spatial scales, or in climate change scenarios, where large temperature ranges may cause static respiration parameters to yield misleading results.
Role of peroxisome proliferator‐activated receptor‐α in acute pancreatitis induced by cerulein
Authors: Genovese Tiziana , Mazzon Emanuela , Di Paola Rosanna , Muià Carmelo , Crisafulli Concetta , Malleo Giuseppe , Esposito Emanuela , Cuzzocrea Salvatore 
Published: June 2006

SummaryThe peroxisome proliferator‐activated receptor‐α (PPAR‐α) is a member of the nuclear receptor superfamily of ligand‐dependent transcription factors related to retinoid, steroid and thyroid hormone receptors. The aim of the present study was to examine the effects of endogenous PPAR‐α ligand on the development of acute pancreatitis caused by cerulein in mice. Intraperitoneal injection of cerulein into PPAR‐α wild‐type (WT) mice resulted in severe, acute pancreatitis characterized by oedema, neutrophil infiltration and necrosis and by elevated serum levels of amylase and lipase. Infiltration of pancreatic and lung tissue with neutrophils (measured as an increase in myeloperoxidase activity) was associated with enhanced expression of the adhesion molecules intercellular adhesion molecule‐1 (ICAM‐1) and P‐selectin. Immunohistochemical examination demonstrated a marked increase in the staining (immunoreactivity) for transforming growth factor‐β (TGF‐β) and vascular endothelial growth factor (VEGF) in the pancreas of cerulein‐treated PPAR‐α wild‐type (WT) mice in comparison to sham‐treated mice. Acute pancreatitis in PPAR‐αWT mice was also associated with a significant mortality (20% survival at 5 days after cerulein administration). In contrast, the degree of pancreatic inflammation and tissue injury (histological score), up‐regulation/formation of ICAM‐1 and P‐selectin, infiltration of neutrophils, and the expression of TGF‐β and VEGF was markedly enhanced in pancreatic tissue obtained from cerulein‐treated PPAR‐α knockout (KO) mice. Thus, endogenous PPAR‐α ligands reduce the degree of pancreas injury caused by acute pancreatitis induced by cerulein administration.
Patient self‐medication – a change in hospital practice
Authors: Grantham Glennice , McMillan Virginia , Dunn Sandra V , Gassner Lee‐Anne , Woodcock Peta 
Published: June 2006

Aims and objectives.  The purpose of this study was to evaluate the effectiveness of a self‐medication programme (SMP) for inpatients of the Nursing Convalescent Unit, a 26‐bed unit with medical and surgical patients.Background.  Self‐medication is an important part of self‐management of chronic illness. Self‐medication is a way of allowing patients to give themselves their medications in hospital after receiving education instead of the usual practice of medications administered by a Registered Nurse (RN).Design.  The pilot study was undertaken over a six‐month period to examine the relationship between a programme of self‐medication and patient knowledge and adherence to medication regimens, number of medication errors, efficiency in relation to the number of nursing hours associated with the SMP, patient and nursing satisfaction.Methods.  A total of 220 patients participated in the study. The SMP included three levels of patient self‐administration of medications: level one, medications administered by a RN; level two, self‐medication directly supervised by a RN and level three, self‐medication indirectly supervised by a RN. Outcome measures included staff and patient satisfaction, number of medication errors, time taken by nurses to undertake activities related to the SMP and the number of patients who achieved levels two and three.Results.  Study findings showed that 45% of patients remained on level one, 26% achieved level two and 29% achieved level three. There were no patient initiated medication errors during the study period. Efficiencies were identified in staff workload associated with patient discharge procedures. Overall, nurses perceived that the SMP increased their knowledge of medications and contributed to effective patient education.Conclusions.  In selected patients, the SMP was an effective aid for improving adherence to medication regimens.Relevance to clinical practice.  Collaboration between nurses, medical staff, pharmacists, patients and carers is integral to the success of in hospital SMP.
Practice development ‘without walls’ and the quandary of corporate practice
Authors: Graham Iain , Fielding Carol , Rooke Debbie , Keen Steven 
Published: June 2006

Aim.  The context of this study is a group of clinical nurse specialists from across a Trust seeking accreditation as a practice development unit. The university was asked to facilitate the accreditation process via 11 2‐hour learning sessions (including a one‐hour focus group). During initial discussions between the university and practice development unit, the overarching research question for this study was set as: ‘what are the main roles and responsibilities of clinical nurse specialists?’Background.  Although there is no known study of a practice development unit based beyond a ward or speciality, the central tenet of the practice development unit literature is that units must demonstrate their worth if they are to survive and harness senior management support in doing so.Design and methods.  Data gleaned from the transcribed audio tape‐recordings of the learning sessions were studied at least three times to ensure transcription accuracy and produce detailed charts. Ethical approval was granted by the appropriate Local Research Ethics Committee and written informed consent obtained from clinical nurse specialists. The study lasted 30 months and ended in October 2004.Results.  The four crucial statements that give meaning to specialist practice are: quality care giver; expert; information giver and initiator of change. Further analysis reveals the area of corporate and political practice as being missing from this and other lists of clinical nurse specialist attributes found in the literature. Clinical nurse specialists characterize their relationship with the Trust in terms of dichotomy – differing agendas and perceptions of value.Conclusions.  The specialist role requires professional development in the areas of corporate and political acumen and professional business management.Relevance to clinical practice.  While the findings of this study relate to one Trust and a group of 16 clinical nurse specialists, with careful application they may be transferable to other settings and groups of senior nurses.
Use of trade‐off theory to advance understanding of herbivore–parasite interactions
Authors: HUTCHINGS MICHAEL R. , JUDGE JOHANNA , GORDON IAIN J. , ATHANASIADOU SPIRIDOULA , KYRIAZAKIS ILIAS 
Published: June 2006

ABSTRACTTrade‐off theory has been extensively used to further our understanding of animal behaviour. In mammalian herbivores, it has been used to advance our understanding of their reproductive, parental care and foraging strategies. Here, we detail how trade‐off theory can be applied to herbivore–parasite interactions, especially in foraging environments.Foraging is a common mode of uptake of parasites that represent the most pervasive challenge to mammalian fitness and survival. Hosts are hypothesized to alter their foraging behaviour in the presence of parasites in three ways: (i) hosts avoid foraging in areas that are contaminated with parasites; (ii) hosts select diets that increase their resistance and resilience to parasites; and (iii) hosts select for foods with direct anti‐parasitic properties (self‐medication). We concentrate on the mammalian herbivore literature to detail the recent advances made using trade‐off frameworks to understand the mechanisms behind host–parasite interactions in relation to these three hypotheses.In natural systems, animals often face complex foraging decisions including nutrient intake vs. predation risk, nutrient intake vs. sheltering and nutrient intake vs. parasite risk trade‐offs. A trade‐off framework is detailed that can be used to interpret mammal behaviour in complex environments, and may be used to advance the self‐medication hypothesis.The use of trade‐off theory has advanced our understanding of the contact process between grazing mammalian hosts and their parasites transmitted via the faecal–oral route. Experimental manipulation of the costs and benefits of a nutrient intake vs. parasite risk trade‐off has shown that environmental conditions (forage quality and quantity) and the physiological state (parasitic and immune status) of a mammalian host can both affect the behavioural decisions of foraging animals.Naturally occurring trade‐offs and the potential to manipulate their costs and benefits enables us to identify the abilities and behavioural rules used by mammals when making decisions in complex environments and thus predict animal behaviour.
Gray whaleEschrichtius robustuspopulation and stock identity
Authors: SWARTZ STEVEN L. , TAYLOR BARBARA L. , RUGH DAVID J. 
Published: June 2006

ABSTRACTIn response to conservation and management concerns about gray whaleEschrichtius robustuspopulation and stock structure, we provide an overview of the life history and ecology of gray whales as a context for discussion of population and stock structure within the species. Historically eastern and western North Pacific gray whales were managed separately because: (i) their ranges do not overlap; (ii) genetic analyses indicate that the two populations are significantly different; and (iii) eastern gray whales have increased in abundance over the past century while western gray whales have not.Here, we review gray whale migration timing and segregation, feeding and prey species, and reproduction and reproductive behaviour. For the eastern and western gray whale, we review their distribution, history of exploitation, abundance and current status, although most of what is known is founded on the better studied eastern gray whale and only implied for the lesser known western gray whale. Methods to investigate population and stock identity are reviewed including genetics, morphology, chemical signatures, carbon isotopes, parasites, photographic identification and trends in abundance.While the evidence indicates that there is at least some degree of mixing within each of the gray whale populations, no stocks or sub‐stocks can be defined. Population structure is not evident in nuclear data, and because selection occurs primarily on the nuclear genome, it is unlikely that there is structuring within each population that could result in evolutionary differences. For western gray whales, there are insufficient data to assess the plausibility of stock structure within the population, owing to its extremely depleted state. Research on eastern gray whales has focused mostly on documenting changes in abundance, feeding biology and behaviour, and suggests separate breeding groups to be unlikely. Both males and females are promiscuous breeders lending little opportunity for the nuclear genome to be anything other than well mixed as is suggested by the high haplotypic diversity of the eastern population.The available data strongly indicate that western gray whales represent a population geographically isolated from eastern gray whales and therefore that the western and eastern populations should be treated as separate management units.
Challenges to re‐enrolling perinatally HIV‐infected and HIV‐exposed but uninfected children into a prospective cohort study: strategies for locating and recruiting hard‐to‐reach families
Authors: Freedman Darcy , Koenig Linda J. , Wiener Jeffrey , Abrams Elaine J. , Carter Rosalind J. , Tepper Vicki , Palumbo Paul , Nesheim Steven , Bulterys Marc 
Published: June 2006

SummaryChildren infected with the human immunodeficiency virus (HIV) are living longer. Studies aimed at understanding the health and well‐being of these children as they age into adolescence are enhanced by research designs that include appropriate comparison groups. HIV‐exposed but uninfected children are one such comparison group; however, recruitment of this comparison group is challenging because uninfected children may no longer be followed at tertiary care centres, and some may be in foster care or no longer living with their biological parents. This paper describes the recruitment methods, sampling plan, and factors associated with enrolling perinatally HIV‐infected children and a comparison group of HIV‐exposed but uninfected children into the HIV Follow‐up Of Perinatally Exposed Children (PACTS‐HOPE) prospective cohort study. The source population consists of HIV‐infected and uninfected children originally enrolled in the Perinatal AIDS Collaborative Transmission Study (PACTS). Recruitment took place at paediatric HIV clinics in four US locations between March 2001 and March 2003.A total of 182 HIV‐infected and 180 uninfected children were enrolled. Enrolment of uninfected children was much harder than that of infected children because the former often could not be located. After adjusting for site and birth‐year category, uninfected children born to white mothers were significantly less likely to be enrolled (P < 0.01). There was a trend for infected and uninfected children of mothers with a history of injection drug use to enrol at lower rates. Although recruitment of the uninfected comparison group was challenging, it was nevertheless facilitated by hierarchical recruitment techniques, involvement of family networks, and continuity of study staff. The PACTS‐HOPE cohort will provide opportunities for future research aimed at understanding the unique effects of HIV on the well‐being of HIV‐infected children.