bluuebunny/crossref_metadata_2025_split huggingface dataset:
Life history and the ecology of stress: how do glucocorticoid hormones influence life‐history variation in animals?
Authors: Crespi Erica J. , Williams Tony D. , Jessop Tim S. , Delehanty Brendan 
Published: November 2012

Summary

Glucocorticoids hormones (GCs) are intuitively important for mediation of age‐dependent vertebrate life‐history transitions through their effects on ontogeny alongside underpinning variation in life‐history traits and trade‐offs in vertebrates. These concepts largely derive from the ability of GCs to alter energy allocation, physiology and behaviour that influences key life‐history traits involving age‐specific life‐history transitions, reproduction and survival.

Studies across vertebrates have shown that the neuroendocrine stress axis plays a role in the developmental processes that lead up to age‐specific early life‐history transitions. While environmental sensitivity of the stress axis allows for it to modulate the timing of these transitions within species, little is known as to how variation in stress axis function has been adapted to produce interspecific variation in the timing of life‐history transitions.

Our assessment of the literature confirms that of previous reviews that there is only equivocal evidence for correlative or direct functional relationships between GCs and variation in reproduction and survival. We conclude that the relationships between GCs and life‐history traits are complex and general patterns cannot be easily discerned with current research approaches and experimental designs.

We identify several future research directions including: (i) integration of proximate and ultimate measures, including longitudinal studies that measure effects of GCs on more than one life‐history trait or in multiple environmental contexts, to test explicit hypotheses about how GCs and life‐history variation are related and (ii) the measurement of additional factors that modulate the effects of GCs on life‐history traits (e.g. GC receptors and binding protein levels) to better infer neurendocrine stress axis actions.

Conceptual models of HPA/I axis actions, such as allostatic load and reactive scope, to some extent explicitly predict the role of GCs in a life‐history context, but are descriptive in nature. We propose that GC effects on life‐history transitions, survival probabilities and fecundity can be modelled in existing quantitative demographic frameworks to improve our understanding of how GC variation influences life‐history evolution and GC‐mediated effects on population dynamics
Invading with biological weapons: the importance of disease‐mediated invasions
Authors: Strauss Alex , White Andy , Boots Mike 
Published: November 2012

Summary

Invasive organisms and emerging wildlife disease pose two of the greatest threats to global biodiversity and ecosystem functioning.

Typically, when parasites are considered in invasion biology, it is in the context of the enemy release hypothesis, wherein a non‐indigenous species has greater probability of invasion success by virtue of leaving its natural enemies, including parasites, behind.

It is also possible that native parasites may prevent invasions, but it is clear that invasive organisms may bring infectious diseases with them that can infect native competitors (via spillover), or act as competent hosts for native diseases, increasing disease prevalence among native species (via spillback).

If the shared disease (either via spillover or spillback) has higher virulence in the native host (which is particularly likely with introduced parasites), there is the potential that the disease can act as a ‘biological weapon’ leading to a disease‐mediated invasion (DMI).

Here, we review cases where disease may have been an important factor mediating a wide range of invasions in vertebrates, invertebrates and plants.

We then focus on the invasion of the grey squirrel into the UK as a case study of a DMI, and we discuss how mathematical models have helped us to understand the importance of this shared disease and its implications for the management of invasive species.

We conclude that (i) DMIs are a widespread phenomenon, that (ii) spillover is more common in animal invasions and spillback more common among plant invasions and that (iii) spillover DMIs are particularly important in explaining the replacement of native animals with phylogenetically similar non‐indigenous species.
Effects of social immunity and unicoloniality on host–parasite interactions in invasive insect societies
Authors: Ugelvig Line V. , Cremer Sylvia 
Published: November 2012

SummarySocial insects have a very high potential to become invasive pest species. Here, we explore how their social lifestyle and their interaction with parasites may contribute to this invasive success.Similar to solitary species, parasite release followed by the evolution of increased competitive ability can promote establishment of introduced social insect hosts in their introduced range.Genetic bottlenecks during introduction of low numbers of founder individuals decrease the genetic diversity at three levels: the population, the colony and the individual, with the colony level being specific to social insects. Reduced genetic diversity can affect both the individual immune system and the collective colony‐level disease defences (social immunity). Still, the dual immune system is likely to make social insects more robust to parasite attack.Changes in social structure from small, family‐based, territorially aggressive societies in native populations towards huge networks of cooperating nests (unicoloniality) occur in some invasive social insects, for example, most invasive ants and some termites.Unicoloniality is likely to affect disease dynamics in multiple ways. The free exchange of individuals within the population leads to an increased genetic heterogeneity among individuals of a single nest, thereby decreasing disease transmission. However, the multitude of reproductively active queens per colony buffers the effect of individual diseased queens and their offspring, which may result in a higher level of vertical disease transmission in unicolonial societies. Lastly, unicoloniality provides a competitive advantage over native species, allowing them to quickly become the dominant species in the habitat, which in turn selects for parasite adaptation to this common host genotype and thus eventually a high parasite pressure.Overall, invasions by insect societies are characterized by general features applying to all introduced species, as well as idiosyncrasies that emerge from their social lifestyle. It is important to study these effects in concert to be able to develop efficient management and biocontrol strategies.
Implications of floral orientation for flight kinematics and metabolic expenditure of hover‐feeding hummingbirds
Authors: Sapir Nir , Dudley Robert 
Published: November 2012

Summary

Nectar‐bearing flowers are characterized by many different shapes, sizes and orientations, which may affect the way hummingbirds feed from them. Many hummingbird‐pollinated flowers are oriented downwards, thereby requiring that trochilids feed while hovering with the bill oriented vertically upward.

We measured body orientations, wingbeat kinematics and hovering metabolic rates for Anna's Hummingbirds (Calypte anna) feeding from artificial flowers that were oriented horizontally, tilted 45° downwards and pointing vertically downwards.

When feeding from vertically oriented flowers, hummingbirds employed an upright body position combined with dorsal head flexion. Additional kinematic adjustments included an increased stroke plane angle relative to the longitudinal body axis and an increased stroke amplitude deriving from increases in the minimum positional angle of the wingbeat.

By contrast, wingbeat frequency, the stroke plane angle relative to horizontal, the ratio of the minimum to maximum positional angles of the wingbeat and the upstroke/downstroke ratio did not vary during feeding from different flower orientations.

Metabolic rates increased by an average (±SD) of 10·8 (±8·8)% for feeding from vertically compared to horizontally oriented flowers.

Feeding from pendent flowers comes with a substantial metabolic cost that may influence floral selection by hummingbirds and thus the evolution of associated pollination syndromes.
Control and host‐dependent activation of insect toxin expression in a root‐associated biocontrol pseudomonad
Authors: Péchy‐Tarr Maria , Borel Naomi , Kupferschmied Peter , Turner Vincent , Binggeli Olivier , Radovanovic Dragica , Maurhofer Monika , Keel Christoph 
Published: November 2012

SummaryPseudomonas fluorescens CHA0 is a root‐associated biocontrol agent that suppresses soil‐borne fungal diseases of crops. Remarkably, the pseudomonad is also endowed with systemic and oral activity against pest insects which depends on the production of the insecticidal Fit toxin. The toxin gene (fitD) is part of a virulence cassette encoding three regulators (FitF, FitG, FitH) and a type I secretion system (FitABC‐E). Immunoassays with a toxin‐specific antibody and transcriptional analyses involving fitG and fitH deletion and overexpression mutants identified LysR family regulator FitG and response regulator FitH as activator and repressor, respectively, of Fit toxin and transporter expression. To visualize and quantify toxin expression in single live cells by fluorescence microscopy, we developed reporters which in lieu of the native toxin protein express a fusion of the Fit toxin with red fluorescent mCherry. In a wild‐type background, expression of the mCherry‐tagged Fit toxin was activated at high levels in insect hosts, i.e. when needed, yet not on plant roots or in batch culture. By contrast, a derepressed fitH mutant expressed the toxin in all conditions. P. fluorescens hence can actively induce insect toxin production in response to the host environment, and FitH and FitG are key regulators in this mechanism.
Reputations and Research Quality in British Political Science: The Importance of Journal and Publisher Rankings in the 2008 RAE
Authors: Allen Nicholas , Heath Oliver 
Published: November 2012

Research Highlights and Abstract The article seeks to make a contribution in the following areas: Departments that submitted a large proportion of books published with a top university press tended to do much better in the 2008 Research Assessment Exercise (RAE), especially in respect of their 4* rating. Departments that submitted large numbers of top-10 journal articles as a proportion of their outputs tended to get higher 4* ratings than departments that submitted only a few. Departments that had a member of staff on the RAE sub-panel saw their 4* rating jump considerably, all other things being equal, suggesting inadequate communication by the sub-panel of its working methods and criteria. The RAE sub-panel's judgements about research quality broadly reflected the judgements of the profession. This article analyses the results of the 2008 Research Assessment Exercise (RAE). It demonstrates that the reputations of political science journals and scholarly publishers can explain the performance of institutions submitted to the RAE's Politics and International Studies sub-panel, and that there were also clear relationships between types of output and research quality. Outputs in top journals and with top presses were strongly associated with 4* quality and research excellence. Moreover, press and journal reputations appeared to have a greater impact than the type of publication. These findings should encourage policy makers to consider more cost-effective and efficient ways of evaluating research.
Accuracy of endoscopic ultrasound‐guided fine needle aspiration cytology on the differentiation of malignant and benign pancreatic cystic lesions: A single‐center experience
Authors: Oguz Dilek , Öztaş Erkin , Kalkan Ismail Hakkı , Tayfur Oyku , Cicek Bahattin , Aydog Gulden , Kurt Mevlut , Beyazit Yavuz , Etik Digdem , Nadir Isilay , Sahin Burhan 
Published: November 2012

ObjectivesThe aim was to compare the use of endoscopic ultrasound‐guided fine needle aspiration (EUS‐FNA) in cytology and the biochemical analysis of cyst fluid, together with the size of the lesion in the differentiation between benign and malignant pancreatic cystic lesions.MethodsData of patients who underwent EUS‐FNA for pancreatic cystic lesions in our center from January 2006 to October 2010 were retrospectively analyzed. The diagnostic accuracy of EUS‐FNA was determined.ResultsOf the 56 patients, 37 (66.1%) had evaluable cytology for diagnosis and sufficient cyst fluid was available for biochemical analysis in 58.9% (33/56) of the patients. The sensitivity, specificity, positive predictive value and negative predictive value of EUS‐FNA for detecting malignancy were 63%, 100%, 100% and 85%, respectively. EUS‐FNA was the most accurate diagnostic method for differentiating malignant and benign pancreatic cystic lesions (88%). Cyst fluid carcinoembryonic antigen (CEA) > 365 ng/mL had a sensitivity of 100% for the detection of malignant cystic lesions.ConclusionsAlthough the rate of insufficient cyst fluid aspiration is high, the combination of cytological evaluation and CEA analysis of cyst fluid obtained by EUS‐FNA is accurate in differentiating malignant cystic lesions from benign ones. Safe techniques are essential to improve the yield of cyst fluid aspiration by EUS.
Presence‐only modelling using MAXENT: when can we trust the inferences?
Authors: Yackulic Charles B. , Chandler Richard , Zipkin Elise F. , Royle J. Andrew , Nichols James D. , Campbell Grant Evan H. , Veran Sophie 
Published: November 2012

Summary

Recently, interest in species distribution modelling has increased following the development of new methods for the analysis of presence‐only data and the deployment of these methods in user‐friendly and powerful computer programs. However, reliable inference from these powerful tools requires that several assumptions be met, including the assumptions that observed presences are the consequence of random or representative sampling and that detectability during sampling does not vary with the covariates that determine occurrence probability.

Based on our interactions with researchers using these tools, we hypothesized that many presence‐only studies were ignoring important assumptions of presence‐only modelling. We tested this hypothesis by reviewing 108 articles published between 2008 and 2012 that used the MAXENT algorithm to analyse empirical (i.e. not simulated) data. We chose to focus on these articles because MAXENT has been the most popular algorithm in recent years for analysing presence‐only data.

Many articles (87%) were based on data that were likely to suffer from sample selection bias; however, methods to control for sample selection bias were rarely used. In addition, many analyses (36%) discarded absence information by analysing presence–absence data in a presence‐only framework, and few articles (14%) mentioned detection probability. We conclude that there are many misconceptions concerning the use of presence‐only models, including the misunderstanding that MAXENT, and other presence‐only methods, relieve users from the constraints of survey design.

In the process of our literature review, we became aware of other factors that raised concerns about the validity of study conclusions. In particular, we observed that 83% of articles studies focused exclusively on model output (i.e. maps) without providing readers with any means to critically examine modelled relationships and that MAXENT's logistic output was frequently (54% of articles) and incorrectly interpreted as occurrence probability.

We conclude with a series of recommendations foremost that researchers analyse data in a presence–absence framework whenever possible, because fewer assumptions are required and inferences can be made about clearly defined parameters such as occurrence probability.
Body image and psychological outcome after severe skin and soft tissue infection requiring intensive care
Authors: HELLGREN E. M. , LAGERGREN P. , LARSSON A. C. , SCHANDL A. R. , SACKEY P. V. 
Published: November 2012

BackgroundPatients with severe skin and soft tissue infection (SSTI) requiring intensive care unit (ICU) stay are commonly treated with antibiotics, surgery and in some centers also with hyperbaric oxygen therapy. Long‐term follow‐up of body image and psychological outcome has not been described despite extensive surgery, potentially altered body image and subsequent psychological problems. The aim was to describe perceived body image and its relation to anxiety, depression and post‐traumatic stress disorder (PTSD)‐related symptoms in patients with severe SSTI 1 year after ICU stay. Specifically, we aimed to assess potential differences related to gender and anatomic site of infection.MethodsFifty patients treated for severe SSTI in the General ICU, Karolinska University Hospital 2008–2010 received the body image scale (BIS), impact of event scale (IES), and hospital anxiety and depression scale (HADS) 1 year after ICU discharge.ResultsAbdominoperineal SSTI was associated with more body image problems than other anatomic sites of infection in both men and women. Generally, women reported higher BIS scores than men (median 9.5 vs. 3.0 of total 30, P < 0.03) indicating more negative body image. A substantial number of patients reported scar dissatisfaction (63.9%), body dissatisfaction (51.1%) and body feeling less whole (51.0%). BIS scores correlated with HADS anxiety (r = 0.59, P < 0.01), depression (r = 0.60, P < 0.01) and IES (r = 0.61, P < 0.01) scores.ConclusionOne year after severe SSTI requiring intensive care, women and patients with abdominoperineal SSTI reported significantly more body image problems. Negative body image was associated with anxiety, depression and PTSD‐related symptoms. Specific follow‐up for SSTI patients is warranted.
Nociceptive stimuli responses at different levels of general anaesthesia and genetic variability
Authors: STORM H. , STØEN R. , KLEPSTAD P. , SKORPEN F. , QVIGSTAD E. , RÆDER J. 
Published: November 2012

BackgroundChanges in skin conductance (SC), clinical stress score (CSS), the bispectral index spectroscopy (BIS) index and the variation in the BIS index may be used to monitor responses to nociceptive stimuli. We wanted to examine these methods during noxious stimulation during general anaesthesia and if the responses were associated with variability in genes related to pain.MethodsSixty patients, given propofol to a BIS level of 40–50, were stimulated with standardised tetanic electrical stimuli during propofol infusion, plasma level of 3 μg/ml alone, or together with remifentanil target plasma level of 3 ng/ml or 10 ng/ml. The CSS, SC, BIS index and the variability of the BIS index were registered. The inter‐individual variation in nociceptive responses was analysed for co‐variation with genotypes of 89 single nucleotide polymorphisms from 23 candidate genes.ResultsDuring tetanic stimuli, CSS and SC increased significantly and were attenuated with increasing level of remifentanil, different from the BIS index and the variation in the BIS index. Polymorphisms in the P‐glycoprotein (ABCB1), tachykinin 1 receptor (TACR1), dopamine receptor D3 (DRD3) and beta arrestin 2 (ARRB2) genes were associated with the co‐variation in SC variables or CSS response or both during standardised nociceptive stimuli (P < 0.05). Because of no corrections for multiple testing, the genetic analyses are explorative, and associations must be tested in further studies.ConclusionThis exploratory study suggests genes that may be tested further with relation to nociceptive response during anaesthesia. SC and CSS may be useful tools for monitoring nociceptive response during general anaesthesia.
Evaluating the effectiveness of five sampling methods for detection of the tomato potato psyllid, Bactericera cockerelli (Šulc) (Hemiptera: Psylloidea: Triozidae)
Authors: Yen Alan L , Madge David G , Berry Nadine A , Yen Jian D L 
Published: November 2012

AbstractOne of the challenges in detecting a pest incursion is the selection of an appropriate sampling technique that is relatively easy to use and inexpensive. Five sampling techniques (sticky traps, water traps, sweep netting, vacuum sampling and direct searching) were used to detect the tomato potato psyllid (Bactericera cockerelli) in potato crops on the North Island of New Zealand. Sticky traps and water traps outperformed the other methods in detecting psyllids. There was weak evidence that water traps outperformed sticky traps, but this difference was minor. Sticky traps closer to the edge of a crop were more likely to catch more psyllids. The results suggest that surveillance for incursion by B. cockerelli into Australia using yellow sticky or water traps would be easier and more time‐effective to implement than other methods and would provide a higher probability of detection if the psyllid was in fact present.
Energetic study of cardioplegic hearts under ischaemia/reperfusion and [Ca2+] changes in cardiomyocytes of guinea‐pig: mitochondrial role
Authors: Ragone M. I. , Torres N. S. , Consolini A. E. 
Published: November 2012

AbstractAimTo study the role of mitochondria in the recovery of guinea‐pig hearts exposed to high‐K+‐cardioplegia (CPG) and ischaemia/reperfusion (I/R)MethodsWe measured contractility and heat release in perfused guinea‐pig hearts and cytosolic and mitochondrial Ca2+ by epifluorescence and confocal microscopy in isolated cardiomyocytes loaded with Fluo‐4 or Rhod‐2.ResultsIn hearts, CPG increased the postischaemic contractile recovery, and this was potentiated by the mNCX blocker clonazepam and the mKATP opener diazoxide, which also prevented the fall in muscle economy. Moreover, CPG prevented the stunning induced by ouabain, which was reduced by clonazepam. In cardiomyocytes, CPG increased fluorescent signals of cytosolic and mitochondrial Ca2+, while the addition of a mNCX blocker (CGP37157) increased cytosolic but reduced mitochondrial [Ca2+]. Ouabain in CPG increased cytosolic Ca2+ and resting heat, but the addition of CGP37157 reduced them, as well as mitochondrial Ca2+.ConclusionsCPG, diazoxide and clonazepam improve postischaemic recovery, respectively, by increasing the Ca2+ cycling and by reducing the mitochondrial Ca2+ uptake either by uniporter or by mNCX. The mitochondria compete with the leaky sarcoplasmic reticulum (SR) as sink of Ca2+ in guinea‐pig hearts, affecting the postischaemic contractility. CPG also prevented the ouabain‐induced dysfunction by avoiding the Ca2+ overload. Ouabain reduced the synergism between CPG and clonazepam suggesting that [Na+]i and SR load influence the mNCX role.