bluuebunny/crossref_metadata_2025 huggingface dataset:
Anandamide in primary sensory neurons: too much of a good thing?
Authors: Sousa‐Valente João , Varga Angelika , Ananthan Kajaluxy , Khajuria Ankur , Nagy Istvan
Published: February 2014

The quest for possible targets for the development of novel analgesics has identified the activation of the cannabinoid type 1 (CB1) receptor outside the CNS as a potential means of providing relief from persistent pain, which currently constitutes an unmet medical need. Increasing tissue levels of the CB1 receptor endogenous ligand N‐arachidonoylethanolamine (anandamide), by inhibiting anandamide degradation through blocking the anandamide‐hydrolysing enzyme fatty acid amide hydrolase, has been suggested to be used to activate the CB1 receptor. However, recent clinical trials revealed that this approach does not deliver the expected relief from pain. Here, we discuss one of the possible reasons, the activation of the transient receptor potential vanilloid type 1 ion channel (TRPV1) on nociceptive primary sensory neurons (PSNs) by anandamide, which may compromise the beneficial effects of increased tissue levels of anandamide. We conclude that better design such as concomitant blocking of anandamide hydrolysis and anandamide uptake into PSNs, to inhibit TRPV1 activation, could overcome these problems.
Endothelial markers are associated with thrombolysis resistance in acute stroke patients
Authors: Faille D. , Labreuche J. , Meseguer E. , Huisse M.‐G. , Ajzenberg N. , Mazighi M.
Published: February 2014

Background and purpose

The endothelium is crucial in maintaining the haemostatic balance between pro‐ and anti‐thrombotic factors. In this pilot study, the association of endothelial biomarkers with arterial recanalization and clinical outcome in the setting of acute ischaemic stroke (AIS) was evaluated amongst patients treated with recombinant tissue plasminogen activator (rt‐PA).

Methods

Sixty‐four AIS patients treated with rt‐PA were prospectively recruited. Blood was collected before thrombolysis and analysed for von Willebrand factor (vWF), soluble thrombomodulin (sTM) and soluble endothelial protein C receptor (sEPCR). Complete recanalization was defined by a Thrombolysis in Myocardial Infarction Score of 3. Favourable clinical outcome was defined by a modified Rankin Score of 0–2 at 90 days.

Results

Amongst the 64 patients, 31 had no documented occlusion, 19 had persistent occlusion and 14 had complete recanalization. After adjustment for confounding factors, these patients presented lower sTM and sEPCR levels than patients with persistent occlusion (median sTM, 21 vs. 48 ng/ml, P = 0.008; median sEPCR, 78 vs. 114 ng/ml, P = 0.018), but similar levels compared with patients without occlusion. vWF levels did not differ between groups. None of these biomarkers was significantly associated with favourable outcome.

Conclusions

Recanalization after thrombolytic therapy is associated with low sTM and sEPCR levels but not with vWF levels. If corroborated in further larger studies, these findings could be helpful in the identification of patients resistant to rt‐PA thrombolysis who could benefit from a modified recanalization therapy.
Long‐term safety and sustained efficacy of extended‐release pramipexole in early and advanced Parkinson's disease
Authors: Hauser R. A. , Schapira A. H. V. , Barone P. , Mizuno Y. , Rascol O. , Busse M. , Debieuvre C. , Fraessdorf M. , Poewe W. ,   the Pramipexole ER Studies Group
Published: February 2014

Background and purpose

To assess the long‐term safety and efficacy of pramipexole as a once‐daily (q.d.) extended‐release oral formulation in early or advanced Parkinson's disease (PD).

Methods

In two double‐blind (DB) studies of early PD and one of advanced PD, active‐treatment arms received pramipexole immediate release (IR) or extended release (ER), with exposure lasting up to 33 weeks. In open‐label (OL) extensions that followed immediately, subjects took ER q.d. for up to 80 weeks, with dosage adjustment permitted (range 0.375–4.5 mg q.d.).

Results

Of 590 subjects completing an early‐PD DB study, 511 entered the early‐PD OL extension; 408 completed it. Reported adverse events (AEs) with incidence ≥10.0% were somnolence (15.1%), peripheral edema (11.7%) and back pain (10.6%). Of 465 subjects completing the advanced‐PD DB study, 391 entered the advanced‐PD OL extension; 329 completed it. Reported AEs with incidence ≥10.0% were dyskinesia (27.4%) and somnolence (13.6%). Impulse control disorders were identified by semi‐structured interview in 13 subjects (1.4% of 902). In exploratory analyses, adjusted mean Unified Parkinson's Disease Rating Scale (UPDRS) Parts II + III scores (excluding ex‐placebo recipients) remained substantially improved from DB baseline scores prior to pramipexole introduction, at −6.6 and −6.3 points amongst ex‐DB‐ER and ex‐DB‐IR recipients after 113 weeks of pramipexole (33 DB plus 80 OL) in early PD, and −11.5 and −9.1 after up to 113 weeks (up to 33 DB plus 80 OL) in advanced PD.

Conclusions

These results support the long‐term safety and efficacy of pramipexole ER in early and advanced PD. AEs were typical for dopaminergic medications, and UPDRS scores suggested sustained symptomatic benefit.
The Social and Economic Mission of Social Enterprises: Dimensions, Measurement, Validation, and Relation
Authors: Stevens Robin , Moray Nathalie , Bruneel Johan
Published: February 2014

Social entrepreneurs have a dominant social mission and generate revenue to ensure financial viability. However, most research treats the extent to which social entrepreneurs actually adhere to social and economic mission as a black box. Performing higher order confirmatory factor analysis on a sample of social enterprises (N∼270), this study identifies dimensions and validates measures for understanding and delineating social and economic missions, and shows how the two constructs relate to each other. The theoretical untangling and the empirical validation of social and economic missions as distinct constructs—and multiple potential constellations of attached relative importance—opens up opportunities for quantitative hypothesis–testing research in social entrepreneurship.
A Potential Metric of the Attractiveness of Bird Song to Humans
Authors: Blackburn Tim M. , Su Shan , Cassey Phill
Published: February 2014

The prevalence of passerines (mostly oscines, or songbirds) in international bird trade suggests that the possession or production of a song that is attractive or desirable to people may contribute to the likelihood of a species being traded. Testing this is difficult because we lack a general and readily available metric that quantifies attractiveness of bird song to humans. We propose and validate such a metric, based on the number of sound files lodged for a species on the Xeno‐Canto website (www.xeno-canto.org). Our hypothesis is that species with more attractive songs are likely to be recorded more often, and so be represented more often in this online bird sound resource, all else being equal. Using a sample of North American and European passerines, we show that song repertoire size and geographic range size are consistently related to the number of recordings on Xeno‐Canto. We use these results to derive a metric (the residuals of a model of the number of recordings in Xeno‐Canto as a function of geographic range size) that may identify songs that are attractive to humans. Bird species whose songs are known to have inspired classical music, including several well known for their songs (e.g. common nightingale, European blackbird), have higher values of the metric than those that have not been referenced in classical music. The metric may help explain which bird species are present in trade, and so contribute to studies of invasion and conservation biology.
At the dawn of hair research – testing the limits of hair follicle regeneration
Authors: Plikus Maksim V.
Published: February 2014

In the late 1960s, tissue recombination studies by Roy Oliver on the model of rat vibrissae provided invaluable information about the morphogenetic properties of hair follicles. Now more than ever, the field is hopeful that a clinically reproducible procedure for cell‐based hair regeneration is achievable. Highly inductive mesenchymal cells are thought to be the key ingredient necessary to achieve robust hair regeneration, and efforts are underway to develop protocols to improve the naturally low inductive properties of human dermal papilla cells. In this respect, the original studies by Oliver provide essential rodent research benchmarks, which current‐day human studies should aim to reach.
A secretory multifunctional serine protease, DegP of Plasmodium falciparum, plays an important role in thermo‐oxidative stress, parasite growth and development
Authors: Sharma Shweta , Jadli Mohit , Singh Anu , Arora Kavita , Malhotra Pawan
Published: February 2014

Plasmodium falciparum heat shock proteins and proteases are known for their indispensable roles in parasite virulence and survival in the host cell. They neutralize various host‐derived stress responses that are deleterious for parasite growth and invasion. We report identification and functional characterization of the first DegP from an apicomplexan (P. falciparum). To determine the molecular identity and functions of the parasite‐encoded DegP, we complemented the Escherichia coli degP null mutant with a putative PfdegP gene, and the results showed that PfDegP complements the growth defect of the temperature sensitive DegP‐deficient mutant and imparts resistance to non‐permissive temperatures and oxidative stress. Molecular interaction studies showed that PfDegP exists as a complex with parasite‐encoded heat shock protein 70, iron superoxide dismutase and enolase. DegP expression is significantly induced in parasite culture upon heat shock/oxidative stress. Our data suggest that the PfDegP protein may play a role in the growth and development of P. falciparum through its ability to confer protection against thermal/oxidative stress. Antibody against DegP showed anti‐plasmodial activity against blood‐stage parasites in vitro, suggesting that PfDegP and its associated complex may be a potential focus for new anti‐malarial therapies.

Structured digital abstract

●PfDegP physically interacts with PfHsp70 and PfEno by anti-bait co-immunoprecipitation (View interaction)

●PfDegP physically interacts with PfEno, PfSod, PfOat, PfHsp70, PfLDH and PfGpi by anti-bait co-immunoprecipitation (View interaction)

●PfHsp-70 and PfDegP co-localize by fluorescence microscopy (View interaction)

●PfDegP physically interacts with PfOat, PfHsp70, PfEno, PfSod, PfGpi and PfLDH by surface plasmon resonance (View interaction)

●PfEno and PfDegP co-localize by fluorescence microscopy (View interaction)

●PfDegP and PfHsp70 co-localize by co-sedimentation through density gradient (View interaction)
Consequences of altered temperature and food conditions for individuals and populations: a Dynamic Energy Budget analysis for Corbicula fluminea in the Rhine
Authors: Petter Gunnar , Weitere Markus , Richter Otto , Moenickes Sylvia
Published: February 2014

On the basis of simulations at two levels of organisation (individuals and populations), we analysed the impact of altered food and temperature conditions on the Asian clam Corbicula fluminea. In particular, we addressed the role of food and temperature in explaining occasional mass mortalities.

A Dynamic Energy Budget Model (DEBM) was used for simulations at the individual level. We calibrated the DEBM successfully using experimental data on growth in length and mass of C. fluminea under four combinations of temperature and food.

The calibrated DEBM was used to simulate the annual growth in length and mass and the reproductive success under different environmental scenarios. In general, an increase in temperature and food concentration resulted in larger and heavier clams and a higher per capita rate of reproduction. However, phytoplankton densities in rivers often fluctuate strongly and densities are high only briefly. Under such conditions, our simulations suggest that the temporal interactions of temperature and food concentration are particularly important and can decisively influence annual growth.

With regard to occasional mass mortalities, it has been hypothesised that increased temperature might induce an unmet metabolic demand and hence starvation. To test this, we simulated the conditions observed in the Rhine in 2003, when there was a severe heat wave and a mass mortality. For this purpose, we used the calibrated DEBM and, in addition, integrated it into a Physiologically Structured Population Model (PSPM) to account for processes at the population level.

Based on these simulations, it seems unlikely that starvation was the main cause of the mass mortality, although not all mechanisms affecting the energy budget are fully understood. However, a prolonged negative energy budget during heat waves can increase the vulnerability of clams to direct effects of high temperatures or additional stressors and might thus be regarded as an important factor indirectly increasing mortality rates.
Effects of nutrient loading, temperature regime and grazing pressure on nutrient limitation of periphyton in experimental ponds
Authors: Trochine Carolina , Guerrieri Marcelo E. , Liboriussen Lone , Lauridsen Torben L. , Jeppesen Erik
Published: February 2014

We studied nutrient limitation of periphytic algae (henceforth periphyton) in 24 mesocosms simulating shallow lakes with two nutrient levels, enriched (with added nitrogen, N, and phosphorus, P) and unenriched (control), and three temperature scenarios, ambient, A2 from the Intergovernmental Panel on Climate Change (IPCC) and A2 + 50%. Periphyton growth (measured as chlorophyll a) was investigated four times in situ using nutrient‐diffusing substrata. The effect of grazing was also manipulated using exclusion cages.

We found that periphyton responded differently to nutrient addition bioassays (N and P) depending on the background nutrient concentration and warming scenario. Our results indicate that single‐nutrient limitation prevailed for periphyton in our experimental temperate shallow lakes. The responses were season sensitive.

Periphyton in the unenriched mesocosms were P‐limited in early summer in the ambient and A2 scenarios, N‐limited in late summer in these two climate scenarios, not nutrient‐limited in autumn and P‐limited in spring in all climate scenarios. Periphyton in the A2 + 50% scenario showed a positive response to N and P added together in early summer.

In contrast, periphyton in the enriched mesocosms showed no clear nutrient limitation, except for short‐term periods of P limitation in the warmer systems. Grazers did not affect the quantitative response of periphyton to nutrient addition, and the concentrations of P and N as well as mean monthly temperature were the main environmental factors driving P or N limitation.

We conclude that warming in low‐productivity lakes affects the seasonality of N limitation and changes the single‐nutrient limitation of periphyton into NP co‐limitation. This last observation suggests that warming reduces the sensitivity of temperate shallow lakes to bottom‐up perturbations.
Long‐term allelopathic control of phytoplankton by the submerged macrophyte Elodea nuttallii
Authors: Vanderstukken Maarten , Declerck Steven A. J. , Decaestecker Ellen , Muylaert Koenraad
Published: February 2014

It is well known that submerged macrophytes can suppress phytoplankton blooms in lakes and thus promote water quality and biodiversity. One of the possible mechanisms through which submerged macrophytes control phytoplankton is by producing allelochemicals that suppress phytoplankton growth rates. The in situ importance of allelopathy, however, is often questioned because it is assumed that phytoplankton communities can rapidly evolve resistance to allelochemicals.

Here, we present the results of two mesocosm experiments in which we evaluated whether the submerged macrophyte Elodea nuttallii is capable of controlling phytoplankton biomass over periods of 4 to 8 weeks. Such a timescale is long relative to the generation time of phytoplankton and is therefore expected to allow the development of resistance through compositional shifts at both population and community levels.

Although the mesocosms were inoculated with a diverse phytoplankton inoculum including species that had previously been exposed to Elodea, phytoplankton biomass remained consistently low during the course of the experiments in the treatments with Elodea. As zooplankton grazing and competition for nutrients and light by macrophytes were excluded in our experiments, this suggests that phytoplankton was controlled by allelopathy.

Dialysis bag assays, performed at the end of each mesocosm experiment, showed that phytoplankton communities from mesocosms with Elodea were equally sensitive to exudates from Elodea than phytoplankton communities from mesocosms without Elodea.

These results suggest that phytoplankton communities do not evolve resistance to allelochemicals from Elodea. This may allow Elodea to control phytoplankton in natural ecosystems over prolonged time periods through allelopathy.
Deletion of the Kv2.1 delayed rectifier potassium channel leads to neuronal and behavioral hyperexcitability
Authors: Speca D. J. , Ogata G. , Mandikian D. , Bishop H. I. , Wiler S. W. , Eum K. , Wenzel H. Jürgen , Doisy E. T. , Matt L. , Campi K. L. , Golub M. S. , Nerbonne J. M. , Hell J. W. , Trainor B. C. , Sack J. T. , Schwartzkroin P. A. , Trimmer J. S.
Published: February 2014

The Kv2.1 delayed rectifier potassium channel exhibits high‐level expression in both principal and inhibitory neurons throughout the central nervous system, including prominent expression in hippocampal neurons. Studies of in vitro preparations suggest that Kv2.1 is a key yet conditional regulator of intrinsic neuronal excitability, mediated by changes in Kv2.1 expression, localization and function via activity‐dependent regulation of Kv2.1 phosphorylation. Here we identify neurological and behavioral deficits in mutant (Kv2.1−/−) mice lacking this channel. Kv2.1−/− mice have grossly normal characteristics. No impairment in vision or motor coordination was apparent, although Kv2.1−/− mice exhibit reduced body weight. The anatomic structure and expression of related Kv channels in the brains of Kv2.1−/− mice appear unchanged. Delayed rectifier potassium current is diminished in hippocampal neurons cultured from Kv2.1−/− animals. Field recordings from hippocampal slices of Kv2.1−/− mice reveal hyperexcitability in response to the convulsant bicuculline, and epileptiform activity in response to stimulation. In Kv2.1−/− mice, long‐term potentiation at the Schaffer collateral – CA1 synapse is decreased. Kv2.1−/− mice are strikingly hyperactive, and exhibit defects in spatial learning, failing to improve performance in a Morris Water Maze task. Kv2.1−/− mice are hypersensitive to the effects of the convulsants flurothyl and pilocarpine, consistent with a role for Kv2.1 as a conditional suppressor of neuronal activity. Although not prone to spontaneous seizures, Kv2.1−/− mice exhibit accelerated seizure progression. Together, these findings suggest homeostatic suppression of elevated neuronal activity by Kv2.1 plays a central role in regulating neuronal network function.
Site‐directed spin labeling‐electron spin resonance mapping of the residues of cyanobacterial clock protein KaiA that are affected by KaiA–KaiC interaction
Authors: Ishii Kentaro , Terauchi Shun , Murakami Reiko , Valencia Swain Jonathan , Mutoh Risa , Mino Hiroyuki , Maki Kosuke , Arata Toshiaki , Ishiura Masahiro
Published: February 2014

The cyanobacterial clock proteins KaiA, KaiB and KaiC interact with each other to generate circadian oscillations. We have identified the residues of the KaiA homodimer affected through association with hexameric KaiC (KaiC6mer) using a spin‐label‐tagged KaiA C‐terminal domain protein (KaiAc) and performing electron spin resonance (ESR) analysis. Cys substitution and/or the attachment of a spin label to residues located at the bottom area of the KaiAc concave surface, a KaiC‐binding groove, hindered the association of KaiAc with KaiC6mer, suggesting that the groove likely mediates the interaction with KaiC6mer. The residues affected by KaiC6mer association were concentrated in the three areas: the concave surface, a lobe‐like structure (a mobile lobe near the concave surface) and a region adjacent to both the concave surface and the mobile lobe. The distance between the two E254, D255, L258 and R252 residues located on the mobile lobe decreased after KaiC association, suggesting that the two mobile lobes approach each other during the interaction. Analyzing the molecular dynamics of KaiAc showed that these structural changes suggested by ESR analysis were possible. Furthermore, the analyses identified three asymmetries in KaiAc dynamic structures, which gave us a possible explanation of an asymmetric association of KaiAc with KaiC6mer.
Consumer response to food labels in an emerging market: the case of Romania
Authors: Festila Alexandra , Chrysochou Polymeros , Krystallis Athanasios
Published: February 2014

This study investigates consumer response to food labels in an emerging market. More specifically, it measures the levels of awareness, objective and perceived understanding, perceived usefulness and perceived trustworthiness of the most prominent food labels found in the Romanian market. An online survey was conducted with a convenience sample of 428 respondents (45.6% males of an average age of 30.6 years). Results revealed that for most respondents, awareness levels towards food labels are generally low, except for the Guideline Daily Amount (GDA) and the organic food labels. Objective understanding towards food labels was relatively high, especially towards those food labels that included a clear text element. Perceived understanding, perceived usefulness and perceived trustworthiness were found to be consistently high with regard to the GDA and the national organic food labels, while the European organic label scored lower. Finally, response to food labels was found to differ between aware and unaware respondents.
Risk factors for death from pandemic influenza in 1918–1919: a case–control study
Authors: Summers Jennifer A. , Stanley James , Baker Michael G. , Wilson Nick
Published: February 2014

Background

Despite the persisting threat from future influenza pandemics, much is still unknown about the risk factors for death from such events, and especially for the 1918–1919 influenza pandemic.

Methods

A case–control study was performed to explore possible risk factors for death from pandemic influenza among New Zealand military personnel in the Northern Hemisphere in 1918–1919 (n = 218 cases, n = 221 controls). Data were compiled from a Roll‐of‐Honour dataset, a dataset of nearly all military personnel involved in the war and archived individual records.

Results

In the fully adjusted multivariable model, the following were significantly associated with increased risk of death from pandemic influenza: age (25–29 years), pre‐pandemic hospitalisations for a chronic condition (e.g. tuberculosis), relatively early year of military deployment, a relatively short time from enlistment to foreign service, and having a larger chest size (e.g. adjusted odds ratio for 90–99 cm versus <90 cm was 2·45; 95% CI=1·47–4·10). There were no significant associations in the fully adjusted model with military rank, occupational class at enlistment, and rurality at enlistment.

Conclusions

This is one of the first published case–control studies of mortality risk factors for the 1918–1919 influenza pandemic. Some of the findings are consistent with previous research on risk factors (such as chronic conditions and age groups), but others appear more novel (e.g., larger chest size). As all such historical analyses have limitations, there is a need for additional studies in other settings as archival World War One records become digitalised.
Influenza vaccination coverage in children with inflammatory bowel disease
Authors: Banaszkiewicz Aleksandra , Klincewicz Beata , Łazowska‐Przeorek Izabella , Grzybowska‐Chlebowczyk Urszula , Kąkol Paulina , Mytyk Aleksandra , Kofla Anna , Radzikowski Andrzej
Published: February 2014

The aim of this study was to evaluate the influenza vaccination status among paediatric patients with inflammatory bowel disease (IBD) in Poland. This was a questionnaire‐based study. 242 patients with IBD and 142 controls were enrolled in the study. Of patients with IBD, 7·8% received an influenza vaccine, compared to 18·3% of controls (P = 0·0013). There were no statistically significant differences in time from IBD diagnosis, disease activity and in drugs, between vaccinated and non‐vaccinated IBD children. In conclusion, the data of our study demonstrate an alarmingly poor influenza vaccination status in the majority of children with IBD. Therefore, there is an unmet need to implement better influenza vaccination strategies for this group of patients.
Special Section: Political Economy and the Future of Latin American Politics
Authors: Smith William C.
Published: February 2014

The field of Latin American politics has undeniably achieved major advances in the last several decades. Nevertheless, one detects a growing intellectual unease and a sense that the excitement engendered by the pathbreaking work and heated debates of previous decades—focusing on authoritarianism, democratization, and market restructuring and related structural transformations—has waned and perhaps given way to a certain “normalization” of our intellectual enterprise.
Historischer Institutionalismus und Vergleichende Föderalismusforschung: Fragestellungen und Analyseperspektiven
Authors: Broschek Jörg
Published: February 2014

Abstract: Abgesehen von wenigen Ausnahmen sind neuere theoretische Entwicklungen im Historischen Institutionalismus bislang kaum von der vergleichenden Föderalismusforschung aufgenommen worden. Der Beitrag diskutiert deshalb die Möglichkeiten, die eine historisch‐institutionalistische Perspektive für die Bearbeitung von zwei zentralen Fragestellungen der vergleichenden Föderalismusforschung bietet: die Frage nach den Entstehungsbedingungen föderativer Systeme sowie die nach deren Entwicklungsdynamik. Für alle zwei Fragestellungen, so die Grundüberlegung des Artikels, hält der Historische Institutionalismus gewinnbringende Analyseinstrumente bereit, die dazu beitragen können, zwischen den weitgehend isolierten Theoriesträngen der Föderalismusforschung zu vermitteln.
Values and Votes: The Indirect Effect of Personal Values on Voting Behavior
Authors: Leimgruber Philipp
Published: February 2014

Recent research from social psychology suggests that personal values predict political behavior, such as vote choice. In contrast to previous studies, it is hypothesized in this article that personal values influence voting behavior only indirectly through political value orientation. Drawing on the personal value concept of Shalom Schwartz, structural equation models based on Swiss electoral data (SELECTS 2007) are applied to test the hypothesis of indirect effects. The empirical analysis shows that the effects of personal values are indeed mediated by political values, but that their indirect impact on vote choice remains substantial. It is argued on a theoretical level that personal values need first to be translated (or transformed) into political values to become effective on voting behavior.
Mid‐IR to Visible Photoluminescence, Dielectric, and Ferroelectric Properties of Er‐Doped KNLN Ceramics
Authors: Wu Xiao , Kwok K.W.
Published: February 2014

Two mole percentage Er‐doped (K0.5Na0.5)1 − xLixNbO3 ceramics have been prepared and their dielectric, ferroelectric, and photoluminescence (PL) properties have been investigated. Under an excitation of 980 nm, the ceramics exhibit intense up‐conversion luminescent emission at 548 nm (green), weak emission at 660 nm (red) as well as strong down‐conversion luminescent emission in near‐infrared (NIR) (1.40–1.65 μm) and mid‐infrared (2.60–2.85 μm) regions. Probably due to the induced structure distortion and reduced local symmetry, the PL intensities of the green, red as well as mid‐infrared emissions are enhanced by the doping of Li+. Our results show that the Li‐doping is effective in establishing a dynamic circulatory energy process to further enhance the PL intensity of the mid‐infrared emission at the expense of the NIR emission. At the optimum doping level of Li+ (~6 mol%), the full bandwidth at half maximum of the mid‐infrared emission reaches a very large value of ~250 nm. The ceramics also exhibit good ferroelectric properties, and thus they should have great potential for multifunctional optoelectronic applications.
Investigation on Crystallization and Optical Properties of Ca1−xLaxF2+x Glass‐Ceramics
Authors: Imanieh Mohammad H. , Martín Inocencio R. , Yekta Bijan Eftekhari , Gonzalez‐Platas Javier , Creus Alberto Hernández
Published: February 2014

Transparent oxyfluoride glass‐ceramics containing Er3+, Yb3+:Ca1−xLaxF2+x nanocrystals, which may have potential applications in the fields of solid‐state laser and luminescence, were prepared. Crystallization of Ca1−xLaxF2+x and behavior of Yb3+ and Er3+ during the heat treatment was investigated. Results showed that alumina content had a significant effect on crystallization of Ca1−xLaxF2+x in the SiO2–Al2O3–CaF2–LaF3 system. Due to the size of phase‐separated areas, the size of the crystals during the heat treatment did not change significantly. After crystallization of Ca1−xLaxF2+x in the glass, the majority of Er3+ ions incorporated into the Ca1−xLaxF2+x crystals during the heat‐treatment process. Time‐resolved luminescence of Er3+ ions in the samples around 842 nm showed that the solubility of Er3+ ions in Ca1−xLaxF3 crystals is higher than pure CaF2 crystals. The glass undergoes an enormous phase separation, which keeps the Yb3+ ions within the other separated phase. Therefore, only at high temperatures (790°C) or with a long heat‐treatment time (72 h), there is a possibility for Yb3+ ions to be incorporated into the fluorine phase.
Structure and Dielectric Properties of BaTiO3–BiYO3 Perovskite Solid Solutions
Authors: Huang Xuechen , Hao Hua , Zhang Shujun , Liu Hanxing , Zhang Wenqin , Xu Qi , Cao Minghe
Published: February 2014

(1−x)BaTiO3–xBiYO3 [(1−x)BT–xBY] polycrystalline ceramics were prepared by solid‐state reaction method. The ceramics are in tetragonal phase when x ≤ 0.04, transform to pseudocubic at x ≥ 0.06, showing a classic ferroelectric to relaxor transition at x = 0.06, where the phase transition temperature was found to shift to higher temperature with increasing frequency. The dielectric permittivity peaks were analyzed by the modified Curie–Weiss law. Both parameters ΔTdiffuse and ΔTrelaxor were found to increase with increasing BY content, demonstrating a stronger relaxor characteristic.
Dielectric and Raman Spectroscopic Studies of Na0.5Bi0.5TiO3–BaSnO3 Ferroelectric System
Authors: Tripathy Satya Narayan , Mishra Karuna Kara , Sen Shrabanee , Pradhan Dillip K.
Published: February 2014

A series of lead‐free perovskite solid solutions of (1 − x) Na0.5Bi0.5TiO3(NBT)—x BaSnO3(BSN), for 0.0 ≤ x ≤ 0.15 have been synthesized using a high‐temperature solid‐state reaction route. The phase transition behaviors are studied using dielectric and Raman spectroscopic techniques. The ferroelectric to relaxor phase transition temperature (TFR) and the temperature corresponding to maximum dielectric permittivity (Tm) are estimated from the temperature‐dependent dielectric data. Dielectric studies show diffuse phase transition around ~335°C in pure NBT and this transition temperature decreases with increase in x. The disappearance of x‐dependence of A1 mode frequency at ~134 cm−1 for x ≥ 0.1 is consistent with rhombohedral‐orthorhombic transition. In situ temperature dependence Raman spectroscopic studies show disappearance and discontinuous changes in the phonon mode frequencies across rhombohedral (x < 0.1)/orthorhombic (x ≥ 0.1) to tetragonal transition.
Contrasting spatio‐temporal climatic niche dynamics during the eastern and western invasions of spotted knapweed in North America
Authors: Broennimann Olivier , Mráz Patrik , Petitpierre Blaise , Guisan Antoine , Müller‐Schärer Heinz
Published: February 2014

Aim

The spotted knapweed (Centaurea stoebe), a plant native to south‐east and central Europe, is highly invasive in North America. We investigated the spatio‐temporal climatic niche dynamics of the spotted knapweed in North America along two putative eastern and western invasion routes. We then considered the patterns observed in the light of historical, ecological and evolutionary factors.

Location

Europe and North America.

Methods

The niche characteristics of the east and west invasive populations of spotted knapweed in North America were determined from documented occurrences over 120 consecutive years (1890–2010). For this investigation, the 2.5 and 97.5 percentiles of values along temperature and precipitation gradients, as given by the two first axes of a principal components analysis (PCA), were calculated. We additionally measured the climatic dissimilarity between invaded sites and the native niche using a multivariate environmental similarity surface (MESS) analysis.

Results

Along both invasion routes, the species established in regions with climatic conditions that were similar to those in the native niche. An initial spread in ruderal habitats always preceded spread in (semi‐)natural habitats. In the east, the niche gradually increased over time until it reached limits similar to the native niche. Conversely, in the west the niche abruptly expanded after an extended time lag into climates not occupied in the native range; only the native cold niche limit was conserved.

Main conclusions

Our study reveals that different niche dynamics have taken place during the eastern and western invasions. This pattern indicates different combinations of historical, ecological and evolutionary factors in the two ranges. We hypothesize that the lack of a well‐developed transportation network in the west at the time of the introduction of spotted knapweed confined the species to a geographically and climatically isolated region. The invasion of dry rangelands may have been favoured during the agricultural transition in the 1930s by release from natural enemies, local adaptation and less competitive vegetation, but further experimental and molecular studies are needed to explain these contrasting niche patterns fully. Our study illustrates the need and benefit of applying large‐scale, temporally explicit approaches to understanding biological invasions.
Oestrogen receptor‐mediated expression of Olfactomedin 4 regulates the progression of endometrial adenocarcinoma
Authors: Duan Chao , Liu Xubin , Liang Shuang , Yang Zheng , Xia Meng , Wang Liantang , Chen Shangwu , Yu Li
Published: February 2014

Endometrial adenocarcinoma is the most common tumour of the female genital tract in developed countries, and oestrogen receptor (ER) signalling plays a pivotal role in its pathogenesis. When we used bioinformatics tools to search for the genes contributing to gynecological cancers, the expression of Olfactomedin 4 (OLFM4) was found by digital differential display to be associated with differentiation of endometrial adenocarcinoma. Aberrant expression of OLFM4 has been primarily reported in tumours of the digestive system. The mechanism of OLFM4 in tumuorigenesis is elusive. We investigated OLFM4 expression in endometrium, analysed the association of OLFM4 with ER signalling in endometrial adenocarcinoma, and examined the roles of OLFM4 in endometrial adenocarcinoma. Expression of OLFM4 was increased during endometrial carcinogenesis, linked to the differentiation of endometrioid adenocarcinoma, and positively related to the expression of oestrogen receptor‐α (ERα) and progesterone receptor. Moreover, ERα‐mediated signalling regulated expression of OLFM4, and knockdown of OLFM4 enhanced proliferation, migration and invasion of endometrial carcinoma cells. Down‐regulation of OLFM4 was associated with decreased cumulative survival rate of patients with endometrioid adenocarcinoma. Our data suggested that impairment of ERα signal‐mediated OLFM4 expression promoted the malignant progression of endometrioid adenocarcinoma, which may have significance for the therapy of this carcinoma.
Fitness valleys constrainHIV‐1's adaptation to its secondary chemokine coreceptor
Authors: da Silva J. , Wyatt S. K.
Published: February 2014

Fitness valleys, in which mutations at different loci are singly deleterious but jointly beneficial, arise because of reciprocal sign epistasis. Recent theoretical work provides analytical approximations of times to cross fitness valleys via three mechanisms: sequential fixation, stochastic tunnelling and recombination. These times depend critically on the effective population size (Ne). Human immunodeficiency virus type 1 (HIV‐1) encounters fitness valleys in adapting to its secondary cell‐surface chemokine coreceptor,CXCR4. Adaptation toCXCR4 tends to occur late in infection and only in about 50% of patients and is associated with disease progression. It has been hypothesized that the need to cross fitness valleys may explain the delayed and inconsistent adaptation toCXCR4. We have identified four fitness valleys from a previous study of fitness epistasis in adaptation toCXCR4 and use estimates of the within‐patient varianceNefor different patient treatment statuses and infection stages (conditions) to estimate times to cross the valleys. These valleys may be crossed predominantly by stochastic tunnelling, although mean crossing times are consistently longer than the durations of the conditions for which they are calculated. These results were confirmed with stochastic simulation. Simulations show that crossing times for a given condition are highly variable and that for each condition there is a low probability of crossing each valley. These findings support the hypothesis that fitness valleys constrain the adaptation ofHIV‐1 toCXCR4. This study provides the first detailed analysis of the evolutionary dynamics associated with empirical fitness valleys.
Intra‐axonal protein aggregation in the peripheral nervous system
Authors: Vital Anne , Meissner Wassillios G. , Canron Marie‐Hélène , Martin‐Negrier Marie‐Laure , Bezard Erwan , Tison François , Vital Claude
Published: February 2014

Intracellular protein aggregates are common pathological hallmarks of many neurodegenerative disorders, and a defect in axonal transport is also incriminated. Here, we studied intra‐axonal abnormal protein aggregation and axonopathy by using immunohistochemistry and electron microscopy on peripheral nerve biopsies from 12 patients with chronic axonal peripheral neuropathy (PN) of unknown etiology. Among these patients, three had idiopathic Parkinson's disease (PD). Intra‐axonal ubiquitin aggregates were more numerous in the patients with PD. Intra‐axonal aggregates of tau AT8 were found in five patients without PD. Phosphorylated α‐synuclein aggregation was absent in all cases, while intra‐axonal colocalization of 14‐3‐3 β and ubiquitin was observed in two PD cases. Electron microscopy revealed enlarged axons crowded with organelles in six cases, including the three patients with PD, thus attesting a slowing of the axoplasmic flux. The number of ubiquitin aggregates was correlated with features of reduced axonal flux, while no such correlation was found for tau and 14‐3‐3 β. Age did not correlate with the number of tau, ubiquitin, and 14‐3‐3 aggregates. Thus, both ubiquitin and/or abnormal tau intra‐axonal aggregates may be found in chronic axonal PN. Ubiquitin aggregates might reduce the axonal flux or result from a disease producing slowing of axonal transport.
Excessive activation of the alternative complement pathway in autosomal dominant polycystic kidney disease
Authors: Su Z. , Wang X. , Gao X. , Liu Y. , Pan C. , Hu H. , Beyer R. P. , Shi M. , Zhou J. , Zhang J. , Serra A. L. , Wüthrich R. P. , Mei C.
Published: February 2014

Objectives

The complement system is involved in many immune complex‐mediated kidney diseases, yet its role in the pathogenesis of autosomal dominant polycystic kidney disease (ADPKD) has not been examined in detail.

Methods and Results

Screening of the glycoproteome of urine samples from ADPKD patients revealed that levels of complement factor B (CFB), serpin peptidase inhibitor, complement component 1 inhibitor (SERPING1) and complement component 9 (C9) increased, whereas complement component 1, r subcomponent‐like (C1RL), CD55 and CD59 levels decreased with disease progression. Immunostaining and Western blot analysis confirmed the enhanced expression of CFB and C9 in cystic kidneys from ADPKD patients. Immunostaining also showed that the expressions of CFB and C9 in renal biopsy tissues from patients with other types of chronic kidney disease were lower than in tissues from ADPKD patients. The effect of the complement inhibitor rosmarinic acid (RMA) was evaluated in Pkd1−/− mice and Han:SPRD Cy/+ rats. Compared with vehicle‐treated Pkd1−/− animals, RMA‐treated mice had significantly lower serum creatinine (−50%) and blood urea nitrogen (−78%) levels, two kidneys/body weight ratio (−60%) and renal cystic index (−60%). Similar results were found in Cy/+ rats. Lower numbers of Ki67‐positive nuclei and inflammatory cells and reduced fibrosis were observed in both animal models upon treatment with RMA.

Conclusions

These results suggest that excessive activation of the alternative complement pathway is associated with ADPKD progression, probably mediated by cyst‐lining epithelial cell proliferation, tubulointerstitial inflammatory cell infiltration and fibrosis. Targeting the complement system might represent a new therapeutic strategy for ADPKD.
Team work engagement: A model of emergence
Authors: Costa Patrícia L. , Passos Ana M. , Bakker Arnold B.
Published: February 2014

Research has shown that work engagement, both at the individual and team levels, is relevant to understand employee performance and well‐being. Nonetheless, there is no theoretical model that explains the development of work engagement in teams that takes into consideration what is already known about team dynamics and processes. This study addresses this gap in the literature, presenting a model for the emergence of team work engagement. The model proposes team inputs, outputs, and mediators as predictors of team work engagement and highlights their recursive influences over time. This conceptual work provides a starting point for further research on team work engagement, allowing for distinguishing individual and team constructs.

Practitioner points

The degree of energy and enthusiasm of teams depends on the way they interact.

The affective and motivational dynamics of teams have consequences for their performance and well‐being.

The emergence of team work engagement is better understood within the literature of teamwork.
The role of oral flora in the development of chemotherapy‐induced oral mucositis
Authors: Stringer Andrea M. , Logan Richard M.
Published: February 2014

Chemotherapy‐induced mucositis is considered to be a major oncological problem, caused by the cytotoxic effects of cancer chemotherapy. In the last 10 years, there have been significant advances in the understanding of mucositis pathobiology. At the basic level, it is now well‐understood that it is not just an epithelial process, but rather a complex interaction between epithelial and connective tissue compartments. There is also potential interaction between the oral microenvironment and the development of mucositis. Changes occur in the resident oral flora (commensal) throughout cancer treatment, and it is conceivable that these organisms and changes that occur may have an influence on the development of mucosal toxicity associated with cancer treatment. The aim of this review was to examine the potential contributions of oral microflora in the pathobiology of mucositis and identify pathways and interactions that could be targeted for therapeutic management of mucositis.
Allelopathic effects of Alexandrium fundyense (Dinophyceae) on Thalassiosira cf. gravida (Bacillariophyceae): a matter of size
Authors: Lyczkowski Emily R. , Karp‐Boss Lee
Published: February 2014

Allelopathic interactions among phytoplankton are well documented. The potency of allelopathic species and responses of target species to allelochemicals are quite variable, however, limiting full understanding of the role these interactions may play in nature. One trait that may influence the sensitivity of an individual to allelochemicals is cell size. The few studies that have examined relationships between cell size and susceptibility to allelochemicals have compared different species and thus could not distinguish between the role of size and species‐specific physiological differences. Culturing an actively sexually reproducing diatom allowed us to focus on the influence of target cell size within a single species. We studied growth and nutrient acquisition by the chain‐forming Thalassiosira cf. gravida Clever in the presence and absence of allelochemicals released by Alexandrium fundyense Balech as a function of T. cf. gravida cell size. Upon exposure to filtrate of A. fundyense, T. cf. gravida cultures “bleached” and both growth and nutrient utilization ceased for up to 4 d. The magnitude of the effect was dependent on filtrate concentration and T. cf. gravida cell surface area:volume ratio. The greatest inhibition was observed on the smallest cells, while T. cf. gravida cultures that had undergone cell enlargement via sexual reproduction were least sensitive to A. fundyense filtrate. These results demonstrate that competitor cell size, independent from taxonomy, may influence the outcome of allelopathic interactions. The findings presented here suggest a potential ecological impact of diatom cell size reduction and sexual reproduction that has not yet been described and that may be important in determining diatom survival and success.
Comparison of a novel non‐contact biomotion sensor with wrist actigraphy in estimating sleep quality in patients with obstructive sleep apnoea
Authors: Pallin Michael , O'hare Emer , Zaffaroni Alberto , Boyle Patricia , Fagan Ciara , Kent Brian , Heneghan Conor , de Chazal Philip , McNicholas Walter T.
Published: February 2014

Ambulatory monitoring is of major clinical interest in the diagnosis of obstructive sleep apnoea syndrome. We compared a novel non‐contact biomotion sensor, which provides an estimate of both sleep time and sleep‐disordered breathing, with wrist actigraphy in the assessment of total sleep time in adult humans suspected of obstructive sleep apnoea syndrome. Both systems were simultaneously evaluated against polysomnography in 103 patients undergoing assessment for obstructive sleep apnoea syndrome in a hospital‐based sleep laboratory (84 male, aged 55 ± 14 years and apnoea–hypopnoea index 21 ± 23). The biomotion sensor demonstrated similar accuracy to wrist actigraphy for sleep/wake determination (77.3%: biomotion; 76.5%: actigraphy), and the biomotion sensor demonstrated higher specificity (52%: biomotion; 34%: actigraphy) and lower sensitivity (86%: biomotion; 94%: actigraphy). Notably, total sleep time estimation by the biomotion sensor was superior to actigraphy (average overestimate of 10 versus 57 min), especially at a higher apnoea–hypopnoea index. In post hoc analyses, we assessed the improved apnoea–hypopnoea index accuracy gained by combining respiratory measurements from polysomnography for total recording time (equivalent to respiratory polygraphy) with total sleep time derived from actigraphy or the biomotion sensor. Here, the number of misclassifications of obstructive sleep apnoea severity compared with full polysomnography was reduced from 10/103 (for total respiratory recording time alone) to 7/103 and 4/103 (for actigraphy and biomotion sensor total sleep time estimate, respectively). We conclude that the biomotion sensor provides a viable alternative to actigraphy for sleep estimation in the assessment of obstructive sleep apnoea syndrome. As a non‐contact device, it is suited to longitudinal assessment of sleep, which could also be combined with polygraphy in ambulatory studies.