bluuebunny/crossref_metadata_2025_split huggingface dataset:
Senescence in duckweed: age‐related declines in survival, reproduction and offspring quality
Authors: Barks Patrick M. , Laird Robert A. 
Published: October 2014

Summary

As they grow old, most organisms experience progressive physiological deterioration resulting in declining rates of survival and reproduction – a seemingly maladaptive phenomenon known as senescence.

Although senescence is usually defined with respect only to survival and reproduction, a third component of fitness, offspring quality, may also decline with age. Few studies, however, have assessed age‐related changes in offspring quality using measures that truly reflect fitness.

In a controlled environment, we tested for age‐related declines in three demographic components of fitness (survival, reproduction and offspring quality) in Lemna minor, a small aquatic plant in the subfamily Lemnoideae (the duckweeds) with a short life span and rapid rate of asexual reproduction. Our primary measure of offspring quality, the intrinsic rate of increase, more closely approximates fitness than measures used in previous studies such as size, life span and total reproductive output.

We observed strong age‐related declines in all three components of fitness: old plants had lower rates of survival and reproduction, and produced lower‐quality offspring than younger plants.

Theoretical and empirical research on the evolutionary biology of senescence should devote more attention to offspring quality. This often unrecognized component of fitness may change with age – as we have shown in L. minor – and may be shaped by, and feed back into, the same evolutionary forces that give rise to senescence.
The consequences of co‐infections for parasite transmission in the mosquito Aedes aegypti
Authors: Duncan Alison B. , Agnew Philip , Noel Valérie , Michalakis Yannis 
Published: October 2014

Summary

Co‐infections may modify parasite transmission opportunities directly as a consequence of interactions in the within‐host environment, but also indirectly through changes in host life history. Furthermore, host and parasite traits are sensitive to the abiotic environment with variable consequences for parasite transmission in co‐infections.

We investigate how co‐infection of the mosquito Aedes aegypti with two microsporidian parasites (Vavraia culicis and Edhazardia aedis) at two levels of larval food availability affects parasite transmission directly, and indirectly through effects on host traits.

In a laboratory infection experiment, we compared how co‐infection, at low and high larval food availability, affected the probability of infection, within‐host growth and the transmission potential of each parasite, compared to single infections. Horizontal transmission was deemed possible for both parasites when infected hosts died harbouring horizontally transmitting spores. Vertical transmission was judged possible for E. aedis when infected females emerged as adults. We also compared the total input number of spores used to seed infections with output number, in single and co‐infections for each parasite.

The effects of co‐infection on parasite fitness were complex, especially for V. culicis. In low larval food conditions, co‐infection increased the chances of mosquitoes dying as larvae or pupae, thus increasing opportunities for V. culicis’ horizontal transmission. However, co‐infection reduced larval longevity and hence time available for V. culicis spore production. Overall, there was a negative net effect of co‐infection on V. culicis, whereby the number of spores produced was less than the number used to seed infection. Co‐infections also negatively affected horizontal transmission of the more virulent parasite, E. aedis, through reduced longevity of pre‐adult hosts. However, its potential transmission suffered less relative to V. culicis.

Our results show that co‐infection can negatively affect parasite transmission opportunities, both directly as well as indirectly via effects on host life history. We also find that transmission is contingent on the combined effect of the abiotic environment.
Revisiting the pyrodiversity–biodiversity hypothesis: long‐term fire regimes and the structure of ant communities in a Neotropical savanna hotspot
Authors: Maravalhas Jonas , Vasconcelos Heraldo L. 
Published: October 2014

Summary

The idea that variable fire regimes (pyrodiversity) may increase habitat heterogeneity and, consequently, increase biodiversity at the landscape level is a relatively old one. However, this idea has been recently challenged by studies showing that the biota of fire‐prone ecosystems is so resilient to fire that variation in fire regime has little ecological consequences.

We evaluated how communities of ants – a dominant faunal group – differ with variation in the frequency and seasonal timing of fire in Brazilian Cerrado (savanna), a global biodiversity hotspot. We compared the number and composition of ant species foraging on the ground and in trees among experimental treatments with three fire frequencies (unburned for 37 years and burned every 2 or 4 years for the past 16 years) and three seasonal timings (early, mid and late dry season) of fire with a biennial frequency.

There were no significant differences in ant species richness in trees, and there were no significant differences in the richness of ground‐dwelling ants among plots burned at different times of the dry season. However, unburned plots had fewer ground‐dwelling ant species than those burned at 2 or 4 year intervals. We detected marked differences in species composition across regimes varying in both the frequency and the timing of fire, which were related to fire‐induced changes in vegetation structure. Over 40% of the overall ant species richness recorded in our study site was attributed to differences in species composition among fire treatments.

Synthesis and applications. Our study shows that Cerrado ant diversity at the landscape scale is promoted by a diversity of fire regimes, and therefore supports the validity of the pyrodiversity–biodiversity hypothesis for the Cerrado biome. Our findings suggest that the current policy of fire suppression in Cerrado protected areas has a negative effect on overall biodiversity and therefore should be reconsidered.
Is Great Britain heading for a Ponto–Caspian invasional meltdown?
Authors: Gallardo Belinda , Aldridge David C. 
Published: October 2014

Summary

The outcome of multiple invasions from a common origin may lead to facilitative interactions because the invaders have co‐evolved under similar environmental conditions. This outcome is often referred to as invasional meltdown, with a resultant increase in invasive species and a decline in native species richness and abundance.

This study seeks to assess the full scope of the threat posed by a high‐risk group of 23 freshwater invaders originating from the Ponto–Caspian region (south‐east Europe) across Great Britain. Ponto–Caspian invaders constitute a group of special concern because they have recently caused a large‐scale invasion into western Europe.

According to a literature review, 76% of reported interactions between Ponto–Caspian invaders are positive (mostly provision of food and commensalism) or neutral (habitat partitioning). Negative interactions (mostly predation) were rare, thus highlighting the ability of Ponto–Caspian invaders to coexist.

At least 14 out of the 23 Ponto–Caspian organisms investigated are well‐established in the Rhine estuary and Dutch ports. Four of them (Hemimysis anomala, Dikerogammarus villosus, D. haemobaphes and Hypania invalida) have recently established in Great Britain. Regression models suggest the rest are under a critical risk of being transported, with four species predicted to have arrived already to Great Britain: Echinogammarus ischnus, Jaera istri, Limnomysis benedeni and D. bispinosus.

According to species distribution models, the cumulative risk of invasion of multiple Ponto–Caspian species, thus invasional meltdown, is highest in the south‐east of England and decreases to the north and west.

Great Britain might be on the brink of invasional meltdown, and as a consequence, confronting the problem of Ponto–Caspian invasive species is a vital element for national biosecurity.

Synthesis and applications. The predictive models and maps developed in this study provide a means for an evidence‐based prioritization of species and habitats for the management of existing and future invasions of Ponto–Caspian species. This integrated approach can be easily applied to risk assess other groups of species and habitats.
Modelling the abundance and distribution of marine birds accounting for uncertain species identification
Authors: Johnston Alison , Thaxter Chris B. , Austin Graham E. , Cook Aonghais S.C.P. , Humphreys Elizabeth M. , Still David A. , Mackay Alastair , Irvine Ryan , Webb Andy , Burton Niall H.K. 
Published: October 2014

SummaryMany emerging methods for ecological monitoring use passive monitoring techniques, which cannot always be used to identify the observed species with certainty. Digital aerial surveys of birds in marine areas are one such example of passive observation and they are increasingly being used to quantify the abundance and distribution of marine birds to inform impact assessments for proposed offshore wind developments. However, the uncertainty in species identification presents a major hurdle to determining the abundance and distribution of individual species.Using a novel analytical approach, we combined data from two surveys in the same area: aerial digital imagery that identified only 23% of individuals to species level and boat survey records that identified 95% of individuals to species level. The data sets were analysed to estimate the effects of environmental covariates on species density and to produce species‐specific estimates of population size.For each digital aerial observation without certain species identification, randomized species assignments were generated using the observed species proportions from the boat surveys. For each species, we modelled several random realizations of species assignments and produced a density surface from the ensemble of models. The uncertainty from each stage of the process was propagated, so that final confidence limits accounted for all sources of uncertainty, including species identification.In the breeding season, several species had higher densities near colonies and this pattern was clearest for three auk species. Sandeel density was an important predictor of the density of several gull species.Synthesis and applications. This method shows it is possible to construct maps of species density in situations in which ecological observations cannot be identified to species level with certainty. The increasing use of passive detection methods is providing many more data sets with uncertain species identification and this method could be used with these data to produce species‐specific abundance estimates. We discuss the advantages of this approach for estimating the abundance and distribution of birds in marine areas, particularly for quantifying the impacts of offshore renewable developments by making the estimates derived from the older digital surveys more comparable to the recently improved surveys.
Partner diversity and identity impacts on plant productivity in Acacia–rhizobial interactions
Authors: Barrett Luke G. , Bever James D. , Bissett Andrew , Thrall Peter H. 
Published: October 2014

Summary

Genetic variation for functionally important traits is ubiquitous in communities of nitrogen‐fixing rhizobia, and while some studies have described significant effects of diversity on the functioning of plant‐associated microbial communities, we lack a systematic test of how rhizobial diversity influences plant productivity.

The complexity of potential interactions among rhizobia and plants complicates the development of general predictions regarding causal relationships between rhizobial diversity and plant productivity. For example, while rhizobial complementarity may result in positive associations between symbiont diversity and plant productivity, antagonistic competition may reduce rhizobial community function.

Using two widespread native Australian Acacia species (A. salicina, A. stenophylla) and experimental rhizobial communities derived from 16 bacterial genotypes naturally associated with these hosts, we examined how the provision of mutualistic benefit varies with rhizobial identity, diversity and phylogenetic relatedness.

Analysis of plant performance in relation to rhizobial genotypic richness revealed that the presence of multiple rhizobial genotypes in the rhizosphere was associated with a general decrease in plant productivity compared to growth with single rhizobial genotypes. Importantly, these results appear to be robust in the face of variation in host identity and host diversity (i.e. one or two species mixtures). We also found that rhizobial genotypic identity and host species significantly influenced plant productivity in Acacia–rhizobia interactions, both in single‐ and multistrain inoculations.

Synthesis. Together, our data show that multiple rhizobia interacting with a single host species creates opportunities for emergent or higher‐order effects that extend beyond those that could be simply predicted based upon outcomes of pairwise interactions and that increased mutualist diversity does not necessarily translate into positive effects on plant growth.
Occupational therapists’ use of advocacy in brain injury rehabilitation settings
Authors: King Donna , Curtin Michael 
Published: October 2014

Background/aimOccupational therapists working in brain injury rehabilitation are required to use the skill of advocacy to ensure that people with a brain injury have the right to engage in their chosen occupations. However, no studies were found exploring the use of advocacy by occupational therapists working in brain injury rehabilitation. To investigate how occupational therapists working in brain injury rehabilitation defined and implemented the skill of advocacy when working with clients.MethodInterpretative phenomenological analysis was used to guide planning, data collection and analysis. Thirteen occupational therapists from six NSW metropolitan, regional and rural brain injury rehabilitation units participated in semi‐structured interviews. All interviews were transcribed and member‐checked prior to in‐depth idiographic, inductive and interrogative analysis of each transcript.FindingsParticipants identified the key elements of advocacy as the representation and education of clients and significant others. They indicated that all brain injury rehabilitation workers used advocacy when working with their clients, but were unable to identify unique ways that occupational therapists used advocacy when compared with other brain injury rehabilitation staff. However, they all felt that occupational therapists were well suited to advocate for clients in brain injury rehabilitation settings.ConclusionAlthough participants had difficulty identifying unique ways in which occupational therapists used advocacy in brain injury rehabilitation settings, they all agreed that advocacy was an important skill for occupational therapists to develop and implement.
The position of tree shrews in the mammalian tree: Comparing multi‐gene analyses with phylogenomic results leaves monophyly of Euarchonta doubtful
Authors: ZHOU Xuming , SUN Fengming , XU Shixia , YANG Guang , LI Ming 
Published: October 2014

AbstractThe well‐accepted Euarchonta grandorder is a pruned version of Archonta nested within the Euarchontoglires (or Supraprimates) clade. At present, it includes tree shrews (Scandentia), flying lemurs (Dermoptera) and primates (Primates). Here, a phylogenomic dataset containing 1912 exons from 22 representative mammals was compiled to investigate the phylogenetic relationships within this group. Phylogenetic analyses and hypothesis testing suggested that tree shrews can be classified as a sister group to Primates or to Glires or even as a basal clade within Euarchontoglires. Further analyses of both modified and original previously published datasets found that the phylogenetic position of tree shrews is unstable. We also found that two of three exonic indels reported as synapomorphies of Euarchonta in a previous study do not unambiguously support the monophyly of such a clade. Therefore, the monophyly of both Euarchonta and Sundatheria (Dermoptera + Scandentia) are suspect. Molecular dating and divergence rate analyses suggested that the ancestor of Euarchontoglires experienced a rapid divergence, which may cause the unresolved position of tree shrews even using the whole genomic data.
Correlating Consumer Perception and Consumer Acceptability of Traditional Doenjang in Korea
Authors: Kim Mina K. , Lee Kwang‐Geun 
Published: October 2014

AbstractDoenjang is a traditional Korean food and is widely used for many Korean foods. Consumer perception and consumer acceptability on the typical sensory characteristics of traditional Doenjang remain unknown. The objective of the current study was to determine the consumer perception on traditional Doenjang characteristics and how preexisting consumer perception influenced the consumer liking for traditionally and commercially manufactured Doenjang. A consumer survey was conducted by presenting 26 sensory descriptions to consumers (n = 82) for check‐all‐that‐apply measurement. Then, a consumer acceptance test was conducted over 2 d on 2 Doenjang samples representing commercially produced Doenjang and traditionally produced Doenjang: Day 1 consumers evaluated without any information (n = 182), and day 2 consumers evaluated samples informed that both samples were made by the “traditional” method (n = 109). Two‐way ANOVA and multivariate analyses were conducted. Consumers’ preexisting perceptions on the typical sensory characteristics of traditionally made Doenjang were similar in that they associate “gu‐soo flavor,” “dark color,” “flavorful,” and “well‐fermented flavor” regardless of consumer demographics and Doenjang user status. However, these consumer perceptions on sensory attributes of traditional Doenjang did not agree with desirable sensory attributes for consumer liking, in that consumers preferred the commercially made Doenjang regardless of the evaluation condition and consumer user status. Findings from the current study therefore suggested a discrepancy between the preexisting current consumer perception and actual consumer acceptability of traditional Doenjang products.
Diversity of Glycosyl Hydrolase Enzymes from Metagenome and Their Application in Food Industry
Authors: Sathya T.A. , Khan Mahejibin 
Published: October 2014

AbstractTraditional use of enzymes for food processing and production of food ingredients resulted in fast‐growing enzyme industries world over. The advances in technologies gave rise to exploring newer enzymes and/or modified enzymes for specific application. Search for novel enzymes that can augment catalytic efficiency and advances in molecular biology techniques including sequencing has targeted microbial diversity through metagenomic approaches for sourcing enzymes from difficult to culture organisms. Such mining studies have received more attention in characterizing hydrolases, their prevalence, broad substrate specificities, stability, and independence of cofactors. The focus on glycosyl hydrolases from metagenome for their application in food sector is reviewed.
Effect of Soybean Lecithin on Iron‐Catalyzed or Chlorophyll‐Photosensitized Oxidation of Canola Oil Emulsion
Authors: Choe Jeesu , Oh Boyoung , Choe Eunok 
Published: October 2014

AbstractThe effect of soybean lecithin addition on the iron‐catalyzed or chlorophyll‐photosensitized oxidation of emulsions consisting of purified canola oil and water (1:1, w/w) was studied based on headspace oxygen consumption using gas chromatography and hydroperoxide production using the ferric thiocyanate method. Addition levels of iron sulfate, chlorophyll, and soybean lecithin were 5, 4, and 350 mg/kg, respectively. Phospholipids (PLs) during oxidation of the emulsions were monitored by high performance liquid chromatography. Addition of soybean lecithin to the emulsions significantly reduced and decelerated iron‐catalyzed oil oxidation by lowering headspace oxygen consumption and hydroperoxide production. However, soybean lecithin had no significant antioxidant effect on chlorophyll‐photosensitized oxidation of the emulsions. PLs in soybean lecithin added to the emulsions were degraded during both oxidation processes, although there was little change in PL composition. Among PLs in soybean lecithin, phosphatidylethanolamine and phosphatidylinositol were degraded the fastest in the iron‐catalyzed and the chlorophyll‐photosensitized oxidation, respectively. The results suggest that addition of soybean lecithin as an emulsifier can also improve the oxidative stability of oil in an emulsion.
Effect of Tocopherol on Atherosclerosis, Vascular Function, and Inflammation in Apolipoprotein E Knockout Mice with Subtotal Nephrectomy
Authors: Shing Cecilia M. , Fassett Robert G. , Peake Jonathan M. , Coombes Jeff S. 
Published: October 2014

SummaryBackground/AimsInflammation and endothelial dysfunction contribute to cardiovascular disease, prevalent in chronic kidney disease (CKD). Antioxidant supplements such as tocopherols may reduce inflammation and atherosclerosis. This study aimed to investigate the effect of tocopherol supplementation on vascular function, aortic plaque formation, and inflammation in apolipoprotein E−/− mice with 5/6 nephrectomy as a model of combined cardiovascular and kidney disease.MethodsNephrectomized mice were assigned to a normal chow diet group (normal chow), a group receiving 1000 mg/kg diet of α‐tocopherol supplementation or a group receiving 1000 mg/kg diet mixed‐tocopherol (60% γ‐tocopherol).ResultsFollowing 12 weeks, in vitro aortic endothelial‐independent relaxation was enhanced with both α‐tocopherol and mixed‐tocopherol (P < 0.05), while mixed‐tocopherol enhanced aortic contraction at noradrenaline concentrations of 3 × 10−7 M to 3 × 10−5 M (P < 0.05), when compared to normal chow. Supplementation with α‐ and mixed‐tocopherol reduced systemic concentrations of IL‐6 (P < 0.001 and P < 0.001, respectively) and IL‐10 (P < 0.05 and P < 0.001, respectively), while α‐tocopherol also reduced MCP‐1 (P < 0.05) and tumor necrosis factor (TNF)‐α (P < 0.05). Aortic sinus plaque area was significantly reduced with α‐tocopherol supplementation when compared to normal chow (P < 0.01).ConclusionTocopherol supplementation favorably influenced vascular function and cytokine profile, while it was also effective in reducing atherosclerosis in the apolipoprotein E−/− mouse with CKD.