bluuebunny/crossref_metadata_2025_split huggingface dataset:
Pollen mixing in pollen generalist solitary bees: a possible strategy to complement or mitigate unfavourable pollen properties?
Authors: Eckhardt Michael , Haider Mare , Dorn Silvia , Müller Andreas 
Published: October 2013

Summary

Generalist herbivorous insects, which feed on plant tissue that is nutritionally heterogeneous or varies in its content of secondary metabolites, often benefit from dietary mixing through more balanced nutrient intake or reduced exposure to harmful secondary metabolites. Pollen is similarly heterogeneous as other plant tissue in its content of primary and secondary metabolites, suggesting that providing their offspring with mixed pollen diets might be a promising strategy for pollen generalist bees to complement nutrient imbalances or to mitigate harmful secondary metabolites of unfavourable pollen.

In the present study, we compared larval performance of the pollen generalist solitary bee species Osmia cornuta (Megachilidae) on five experimental pollen diets that consisted of different proportions of unfavourable pollen diet of Ranunculus acris (Ranunculaceae) and favourable pollen diet of Sinapis arvensis (Brassicaceae). In addition, we microscopically analysed the pollen contained in the scopal brushes of field‐collected females of O. cornuta and three closely related species to elucidate to what degree these pollen generalist bees mix pollen of different hosts in their brood cells.

In striking contrast to a pure Ranunculus pollen diet, which had a lethal effect on most developing larvae of O. cornuta, larval survival, larval development time and adult body mass of both males and females remained nearly unaffected by the admixture of up to 50% of Ranunculus pollen diet to the larval food.

Between 42% and 66% of all female scopal pollen loads analysed contained mixtures of pollen from two to six plant families, indicating that pollen mixing is a common behaviour in O. cornuta and the three related bee species.

The present study provides the first evidence that the larvae of pollen generalist bees can benefit from the nutrient content of unfavourable pollen without being negatively affected by its unfavourable chemical properties if such pollen is mixed with favourable pollen. We conclude that the widespread pollen mixing by females of pollen generalist bees should also be considered as a possible strategy to exploit flowers with unfavourable pollen and to optimize larval food quality.
Changes in predator community structure shifts the efficacy of two warning signals in Arctiid moths
Authors: Nokelainen Ossi , Valkonen Janne , Lindstedt Carita , Mappes Johanna 
Published: October 2013

Summary

Polymorphism in warning coloration is puzzling because positive frequency‐dependent selection by predators is expected to promote monomorphic warning signals in defended prey.

We studied predation on the warning‐coloured wood tiger moth (Parasemia plantaginis) by using artificial prey resembling white and yellow male colour morphs in five separate populations with different naturally occurring morph frequencies.

We tested whether predation favours one of the colour morphs over the other and whether that is influenced either by local, natural colour morph frequencies or predator community composition.

We found that yellow specimens were attacked less than white ones regardless of the local frequency of the morphs indicating frequency‐independent selection, but predation did depend on predator community composition: yellows suffered less attacks when Paridae were abundant, whereas whites suffered less attacks when Prunellidae were abundant.

Our results suggest that spatial heterogeneity in predator community composition can generate a geographical mosaic of selection facilitating the evolution of polymorphic warning signals. This is the first time this mechanism gains experimental support. Altogether, this study sheds light on the evolution of adaptive coloration in heterogeneous environments.
Individual‐based analyses reveal limited functional overlap in a coral reef fish community
Authors: Brandl Simon J. , Bellwood David R. 
Published: October 2013

Summary

Detailed knowledge of a species’ functional niche is crucial for the study of ecological communities and processes. The extent of niche overlap, functional redundancy and functional complementarity is of particular importance if we are to understand ecosystem processes and their vulnerability to disturbances.

Coral reefs are among the most threatened marine systems, and anthropogenic activity is changing the functional composition of reefs. The loss of herbivorous fishes is particularly concerning as the removal of algae is crucial for the growth and survival of corals. Yet, the foraging patterns of the various herbivorous fish species are poorly understood.

Using a multidimensional framework, we present novel individual‐based analyses of species’ realized functional niches, which we apply to a herbivorous coral reef fish community. In calculating niche volumes for 21 species, based on their microhabitat utilization patterns during foraging, and computing functional overlaps, we provide a measurement of functional redundancy or complementarity. Complementarity is the inverse of redundancy and is defined as less than 50% overlap in niche volumes.

The analyses reveal extensive complementarity with an average functional overlap of just 15·2%. Furthermore, the analyses divide herbivorous reef fishes into two broad groups. The first group (predominantly surgeonfishes and parrotfishes) comprises species feeding on exposed surfaces and predominantly open reef matrix or sandy substrata, resulting in small niche volumes and extensive complementarity. In contrast, the second group consists of species (predominantly rabbitfishes) that feed over a wider range of microhabitats, penetrating the reef matrix to exploit concealed surfaces of various substratum types. These species show high variation among individuals, leading to large niche volumes, more overlap and less complementarity.

These results may have crucial consequences for our understanding of herbivorous processes on coral reefs, as algal removal appears to depend strongly on species‐specific microhabitat utilization patterns of herbivores. Furthermore, the results emphasize the capacity of the individual‐based analyses to reveal variation in the functional niches of species, even in high‐diversity systems such as coral reefs, demonstrating its potential applicability to other high‐diversity ecosystems.
Does reduced mobility through fragmented landscapes explain patch extinction patterns for three honeyeaters?
Authors: Harrisson Katherine A. , Pavlova Alexandra , Amos J. Nevil , Radford James Q. , Sunnucks Paul 
Published: October 2013

Summary

Habitat loss and associated fragmentation are major drivers of biodiversity decline, and understanding how they affect population processes (e.g. dispersal) is an important conservation goal. In a large‐scale test employing 10 × 10 km units of replication, three species of Australian birds, the fuscous honeyeater, yellow‐tufted honeyeater and white‐plumed honeyeater, responded differently to fragmentation. The fuscous and yellow‐tufted honeyeaters are ‘decliners’ that disappeared from suitable habitat in landscapes where levels of tree‐cover fell below critical thresholds of 17 and 8%, respectively. The white‐plumed honeyeater is a ‘tolerant’ species whose likelihood of occurrence in suitable habitat was independent of landscape‐level tree‐cover.

To determine whether the absence of the two decliner species in low tree‐cover landscapes can be explained by reduced genetic connectivity, we looked for signatures of reduced mobility and gene flow in response to fragmentation across agricultural landscapes in the Box‐Ironbark region of north‐central Victoria, Australia.

We compared patterns of genetic diversity and population structure at the regional scale and across twelve 100 km2 landscapes with different tree‐cover extents. We used genetic data to test landscape models predicting reduced dispersal through the agricultural matrix. We tested for evidence of sex‐biased dispersal and sex‐specific responses to fragmentation.

Reduced connectivity may have contributed to the disappearance of the yellow‐tufted honey‐eater from low tree‐cover landscapes, as evidenced by male bias and increased relatedness among males in low tree‐cover landscapes and signals of reduced gene flow and mobility through the agricultural matrix. We found no evidence for negative effects of fragmentation on gene flow in the other decliner, the fuscous honeyeater, suggesting that undetected pressures act on this species. As expected, there was no evidence for decreased movement through fragmented landscapes for the tolerant white‐plumed honeyeater.

We demonstrated effects of habitat loss and fragmentation (stronger patterns of genetic differentiation, increased relatedness among males) on the yellow‐tufted honeyeater above the threshold at which probability of occurrence dropped. Increasing extent and structural connectivity of habitat should be an appropriate management action for this species and other relatively sedentary woodland specialist species for which it can be taken as representative.
let‐7‐repressesed Shc translation delays replicative senescence
Authors: Xu Fang , Pang Lijun , Cai Xiaoyu , Liu Xinwen , Yuan Shuai , Fan Xiuqin , Jiang Bin , Zhang Xiaowei , Dou Yali , Gorospe Myriam , Wang Wengong 
Published: October 2013

SummaryThe p66Shc adaptor protein is an important regulator of lifespan in mammals, but the mechanisms responsible are still unclear. Here, we show that expression of p66Shc, p52Shc, and p46Shc is regulated at the post‐transcriptional level by the microRNA let‐7a. The levels of let‐7a correlated inversely with the levels of Shc proteins without affecting Shc mRNA levels. We identified ‘seedless’ let‐7a interaction elements in the coding region of Shc mRNA; mutation of the ‘seedless’ interaction sites abolished the regulation of Shc by let‐7a. Our results further revealed that repression of Shc expression by let‐7a delays senescence of human diploid fibroblasts (HDFs). In sum, our findings link let‐7a abundance to the expression of p66Shc, which in turn controls the replicative lifespan of HDFs.
The total number of lymph nodes in resected colon cancer specimens is affected by several factors but the lymph node ratio is independent of these
Authors: Stanisavljević Luka , Søndenaa Karl , Storli Kristian Eeg , Leh Sabine , Nesvik Idunn , Gudlaugsson Einar , Bukholm Ida , Eide Geir Egil 
Published: October 2013

The number of lymph nodes retrieved from the specimen may be a surrogate measure of the adequacy of extensive colon cancer surgery, but many variables may influence the total lymph node yield of any specimen. We examined which variables would be influential both for negative and positive node sampling.The combined results from 428 patients from three hospitals A to C treated in 2007–2009 with single colon cancers having R0 segmental resections were analysed. The surgical technique and pathology staining methods were slightly different between the hospitals.The mean number of lymph nodes was 15.8 (range 1–60). Twelve or more lymph nodes were harvested in 78% of the specimens. In the multivariate Poisson regression analysis of all TNM stages, the factors associated with the total lymph node harvest were age, pathology handling, tumour location and size (p < 0.001), whereas for TNM stage III alone the pathology handling (p < 0.001) and a radical operating technique (p = 0.003) were highly significant. The total number of lymph nodes was the only significant factor for the number of positive lymph nodes (Posln) according to the multivariate negative regression analysis (p = 0.02) but the analysis of the lymph node ratio (LNR) detected no statistically significant variable.Several factors, and especially the specimen processing technique, were important for the total number of harvested lymph nodes. The number of Posln varied between segments and increased with the total number of harvested lymph nodes, but for LNR no variable was important. LNR seemed to abolish the combined effect of tumour location and the total lymph node yield in prognosis assessment.
Stimulation of Suicidal Erythrocyte Death by Ribavirin
Authors: Oswald Gergely , Alzoubi Kousi , Abed Majed , Lang Florian 
Published: October 2013

AbstractRibavirin is widely used in the treatment for viral disease such as chronic viral hepatitis. Side effects limiting the use of the drug include haemolytic anaemia. If challenged by stimulators of haemolysis, erythrocytes may enter suicidal death or eryptosis, thus preventing the release of haemoglobin into circulating blood. Eryptosis is characterized by cell shrinkage and by cell membrane scrambling with phosphatidylserine translocation to the erythrocyte surface. Eryptosis may be triggered by increase in cytosolic Ca2+ activity ([Ca2+]i). This study explored whether ribavirin modifies [Ca2+]i and elicits eryptosis. Cell volume has been estimated from forward scatter, phosphatidylserine abundance at the erythrocyte surface from annexin V binding, haemolysis from haemoglobin release and [Ca2+]i from Fluo‐3 fluorescence. A 48‐hr exposure to ribavirin (≥8 μg/ml) was followed by a significant increase in [Ca2+]i, a significant decrease in forward scatter and a significant increase in annexin V binding. The annexin V binding after ribavirin treatment was significantly blunted but not abolished in the nominal absence of extracellular Ca2+. In conclusion, ribaverin stimulates eryptosis, an effect at least in part due to entry of extracellular Ca2+.
Advances in understanding the pathogenesis of autoimmune disorders: focus on chemokines and lymphocyte trafficking
Authors: Comerford Iain , Kara Ervin E. , McKenzie Duncan R. , McColl Shaun R. 
Published: October 2013

SummaryLymphocyte trafficking is a key step in the pathogenesis of various autoimmune diseases. Recruitment of autoreactive lymphocytes to inflamed tissues is a defining feature of numerous persistent organ‐specific autoimmune conditions and various therapies are now used in several of these diseases which appear to specifically block lymphocyte migration. Thus, better understanding of the molecular events involved in homing of autoreactive pathogenic lymphocytes may present novel opportunities for pharmacological intervention in autoimmune diseases, such as multiple sclerosis, rheumatoid arthritis, type‐1 diabetes and psoriasis. This review describes recent progress in understanding lymphocyte trafficking in autoimmunity, focusing on the involvement of the chemokine and chemokine receptor superfamily. Possible strategies to improve therapeutics for autoimmune diseases arising from these studies are discussed.
The influence of psychological factors on post‐partum weight retention at 9 months
Authors: Phillips Joanne , King Ross , Skouteris Helen 
Published: October 2013

ObjectivesPost‐partum weight retention (PWR) has been identified as a critical pathway for long‐term overweight and obesity. In recent years, psychological factors have been demonstrated to play a key role in contributing to and maintaining PWR.DesignTherefore, the aim of this study was to explore the relationship between post‐partum psychological distress and PWR at 9 months, after controlling for maternal weight factors, sleep quality, sociocontextual influences, and maternal behaviours.MethodPregnant women (N = 126) completed a series of questionnaires at multiple time points from early pregnancy until 9 months post‐partum.ResultsHierarchical regression indicated that gestational weight gain, shorter duration (6 months or less) of breastfeeding, and post‐partum body dissatisfaction at 3 and 6 months are associated with higher PWR at 9 months; stress, depression, and anxiety had minimal influence.ConclusionInterventions aimed at preventing excessive PWR should specifically target the prevention of body dissatisfaction and excessive weight gain during pregnancy.Statement of contributionWhat is already known on this subject?
Post‐partum weight retention (PWR) is a critical pathway for long‐term overweight and obesity.
Causes of PWR are complex and multifactorial.
There is increasing evidence that psychological factors play a key role in predicting high PWR.
What does this study add?
Post‐partum body dissatisfaction at 3 and 6 months is associated with PWR at 9 months post‐birth.
Post‐partum depression, stress and anxiety have less influence on PWR at 9 months.
Interventions aimed at preventing excessive PWR should target body dissatisfaction.
A randomized controlled trial of a home and school‐based intervention for selective mutism – defocused communication and behavioural techniques
Authors: Oerbeck Beate , Stein Murray B. , Wentzel‐Larsen Tore , Langsrud Øyvind , Kristensen Hanne 
Published: October 2013

BackgroundRandomized controlled psychosocial treatment studies on selective mutism (SM) are lacking.MethodOverall, 24 children with SM, aged 3–9 years, were randomized to 3 months treatment (n = 12) or wait list (n = 12). Primary outcome measure was the School Speech Questionnaire.ResultsA significant time by group interaction was found (p = .029) with significantly increased speech in the treatment group (p = .004) and no change in wait list controls (p = .936). A time by age interaction favoured younger children (p = .029). Clinical trail registration: Norwegian Research CouncilNCT01002196.ConclusionsThe treatment significantly improved speech. Greater improvement in the younger age group highlights the importance of an early intervention.
Why are children and adolescents referred for psychiatric assessment without fulfiling diagnostic criteria for any psychiatric disorder?
Authors: Dallos Gyöngyvér , Keresztény Ágnes , Miklósi Mónika , Gádoros Júlia , Balázs Judit 
Published: October 2013

BackgroundClinicians often experience that children are referred for psychiatric evaluation without fulfiling the diagnostic criteria of any psychiatric disorders. This study investigates factors that might lead children to psychiatric referral without any psychiatric disorder.MethodChildren/adolescents who were referred for psychiatric assessment (referred group) (n = 418, mean age = 10.82 years, SD = 3.81) and a control group (n = 48, mean age = 10.38 years, SD = 3.77) were evaluated by the Mini International Neuropsychiatric Interview Kid (MINI Kid) and the Erfassung der Lebensqualität Kindern und Jugendlichen (Measure of Quality of Life for Children and Adolescents). The referred group was further divided into two subgroups: referred subgroup without MINI Kid diagnosis (n = 61) and referred subgroup with MINI Kid diagnosis (n = 357). Subjects less than 18 years old were included and there was no lower age limit.ResultsAttention‐deficit/hyperactivity disorder (ADHD) symptoms significantly increased the odds for referral as social phobia symptoms significantly decreased the odds for psychiatric referral. Regarding quality of life (QoL), the control group showed significantly less impairment when compared with the referred group; the two referred subgroup with and without diagnosis did not differ significantly.ConclusionsADHD symptoms, even in a subthreshold level and impaired QoL represent risk factors for psychiatric referral in children. Secondary prevention of children should target to screen subthreshold ADHD symptoms and QoL.
Glia Protein Aquaporin‐4 Regulates Aversive Motivation of Spatial Memory in Morris Water Maze
Authors: Zhang Ji , Li Ying , Chen Zhong‐Guo , Dang Hui , Ding Jian‐Hua , Fan Yi , Hu Gang 
Published: October 2013

SummaryAimsAlthough extensive investigation has revealed that an astrocyte‐specific protein aquaporin‐4 (AQP4) participates in regulating synaptic plasticity and memory, a functional relationship between AQP4 and learning processing has not been clearly established. This study was designed to test our hypothesis that AQP4 modulates the aversive motivation in Morris water maze (MWM).Methods and ResultsUsing hidden platform training, we observed that AQP4 KO mice significantly decreased their swimming velocity compared with wild‐type (WT) mice. To test for a relationship between velocities and escape motivation, we removed the platform and subjected a new group of mice similar to the session of hidden platform training. We found that KO mice exhibited a gradual reduction in swimming velocity, while WT mice did not alter their velocity. In the subsequent probe trial, KO mice after no platform training significantly decreased their mean velocity compared with those KO mice after hide platform training. However, all of KO mice were not impaired in their ability to locate a visible, cued escape platform.ConclusionsOur findings, along with a previous report that AQP4 regulates memory consolidation, implicate a novel role for this glial protein in modulating the aversive motivation in spatial learning paradigm.
Increase in Neuroexcitability of Unmyelinated C‐type Vagal Ganglion Neurons During Initial Postnatal Development of Visceral Afferent Reflex Functions
Authors: Qian Zhao , Liu Dong‐Jie , Liu Yang , Han Li‐Min , Yuan Mei , Li Jun‐Nan , Xu Bing , Lu Xiao‐Long , Cao Pan‐Xiang , Wang Hao‐Yan , Pan Xiao‐Dong , Wang Li‐Juan , Qiao Guo‐Fen , Li Bai‐Yan 
Published: October 2013

SummaryBackgroundBaroreflex gain increase up closely to adult level during initial postnatal weeks, and any interruption within this period will increase the risk of cardiovascular problems in later of life span. We hypothesize that this short period after birth might be critical for postnatal development of vagal ganglion neurons (VGNs).MethodsTo evaluate neuroexcitability evidenced by discharge profiles and coordinate changes, ion currents were collected from identified A‐ and C‐type VGNs at different developmental stages using whole‐cell patch clamping.ResultsC‐type VGNs underwent significant age‐dependent transition from single action potential (AP) to repetitive discharge. The coordinate changes between TTX‐S and TTX‐R Na+ currents were also confirmed and well simulated by computer modeling. Although 4‐AP or iberiotoxin age dependently increased firing frequency, AP duration was prolonged in an opposite fashion, which paralleled well with postnatal changes in 4‐AP‐ and iberiotoxin‐sensitive K+ current activity, whereas less developmental changes were verified in A‐types.ConclusionThese data demonstrate for the first time that the neuroexcitability of C‐type VGNs increases significantly compared with A‐types within initial postnatal weeks evidenced by AP discharge profiles and coordinate ion channel changes, which explain, at least in part, that initial postnatal weeks may be crucial for ontogenesis in visceral afferent reflex function.