bluuebunny/crossref_metadata_2025_split huggingface dataset:
White‐Emitting Tuning and Energy Transfer in Eu2+/Mn2+‐Substituted Apatite‐Type Fluorophosphate Phosphors
Authors: Guo Ning , Jia Chengzheng , Li Jing , Zhao Yuefeng , Ouyang Ruizhuo , Lü Wei 
Published: December 2014

Herein, a series of Eu2+&Mn2+substituted fluorophosphates Ca6Gd2Na2(PO4)6F2 phosphor with apatite structure have been synthesized and investigated by the powder X‐ray diffraction, photoluminescence spectra, fluorescence decay curves, thermal quenching, and chromaticity properties. Particularly, both Eu2+ and Mn2+ emissions at the two different lattice sites 4f and 6h in Ca6Gd2Na2(PO4)6F2 matrix have been identified and discussed. The dual energy transfer of Eu2+→Mn2+ and Gd3+→Mn2+ in Ca6Gd2Na2(PO4)6F2:Eu2+,Mn2+ samples have been validated and confirmed by the photoluminescence spectra. The dependence of color‐tunable on the activator concentration of Mn2+ was investigated to realize white light emission. By varying the doping concentration of the Mn2+ ion, a series of tunable colors including pure white light and candle light are obtained under the excitation of 350 nm. Moreover, the fluorescence decay curves have been fitted and analyzed using the Inokuti–Hirayama theoretical model to estimate the Eu–Mn interaction mechanism. We also investigated temperature‐dependent photoluminescence quenching characteristics according to the Arrhenius equation. Preliminary studies on the properties of the phosphor indicated that the obtained phosphors might have potential application as a single‐component white‐emitting phosphor for UV‐based white LEDs.
In Situ Diffraction from Levitated Solids Under Extreme Conditions—Structure and Thermal Expansion in the Eu2O3–ZrO2 System
Authors: Maram Pardha S. , Ushakov Sergey V. , Weber Richard J.K. , Benmore Chris J. , Navrotsky Alexandra 
Published: December 2014

The accurate determination of structure and thermal expansion of refractory materials at temperatures above 1500°C is challenging. Here, for the first time, we demonstrate the ability to reliably refine the structure and thermal expansion coefficient of oxides at temperatures to 2200°C using in situ synchrotron diffraction coupled with aerodynamic levitation. Solid solutions in the Eu2O3–ZrO2 binary system were investigated, including the high‐temperature order–disorder transformation in Eu2Zr2O7. The disordered fluorite phase is found to be stable above 1900°C, and a reversible phase transition to the pyrochlore phase is noticed during cooling. Site occupancies in Eu2Zr2O7 show a gradual increase in disorder on both cation and anion sublattices with increasing temperature. The thermal expansion coefficients of all cubic solid solutions are relatively similar, falling in the range 8.6–12.0 × 10−6 C−1. These studies open new vistas for in situ exploration of complex structural changes in high‐temperature materials.
Self‐Reported Walking Difficulty Predicts Late‐Life Mortality in Finnish War Veterans: Results from the Veteran 1992 Project Survey
Authors: Leskinen Riitta , Laatikainen Tiina , Peltonen Markku , Levälahti Esko , Antikainen Riitta 
Published: December 2014

ObjectivesTo determine risk factors and their combinations that predict late‐life mortality.DesignPostal questionnaire.SettingVeteran 1992 Project Survey.ParticipantsFinnish Second World War veterans living in Finland (177,989 men, 48,745 women), with a participation rate of 93%.MeasurementsMain outcomes were total, cardiovascular disease (CVD), and accident and violence (AAV) mortality. Absolute 10‐year mortality risks for total mortality with combinations of different risk factors were calculated.ResultsThe strongest predictor of total mortality was self‐reported walking difficulty (hazard ratio (HR) = 1.74, 95% confidence interval (CI) = 1.71–1.76 in men without disability, HR = 1.62, 95% CI = 1.58–1.67 in men with disability, HR = 1.61, 95% CI = 1.57–1.65 in women). The highest HRs of CVD mortality were for self‐reported walking difficulty among men without disability (HR = 1.98, 95% CI = 1.95–2.02) and among men with disability (HR = 1.88, 95% CI = 1.82–1.94). In women, the highest HR for CVD mortality was for multimorbidity (HR = 1.87, 95% CI = 1.79–1.96). For AAV mortality, the highest HRs were for falls in men and age in women. A combination of walking difficulty and multimorbidity had the highest absolute 10‐year mortality risk for total mortality (0.730 in men without disability, 0.729 in men with disability, 0.487 in women).ConclusionSelf‐reported walking difficulty was the most important predictor of total mortality in all veteran groups and for CVD mortality in men. The study demonstrates the importance of self‐reported walking difficulty and multimorbidity as markers of high mortality risk in Finnish war veterans.
Comparison of the deleterious effects of binge drinking‐like alcohol exposure in adolescent and adult mice
Authors: Lacaille Hélène , Duterte‐Boucher Dominique , Liot Donovan , Vaudry Hubert , Naassila Mickael , Vaudry David 
Published: December 2014

AbstractA major cause of alcohol toxicity is the production of reactive oxygen species generated during ethanol metabolism. The aim of this study was to compare the effect of binge drinking‐like alcohol exposure on a panel of genes implicated in oxidative mechanisms in adolescent and adult mice. In adolescent animals, alcohol decreased the expression of genes involved in the repair and protection of oxidative DNA damage such as atr, gpx7, or nudt15 and increased the expression of proapoptotic genes such as casp3. In contrast, in the adult brain, genes activated by alcohol were mainly associated with protective mechanisms that prevent cells from oxidative damage. Whatever the age, iterative binge‐like episodes provoked the same deleterious effects as those observed after a single binge episode. In adolescent mice, multiple binge ethanol exposure substantially reduced neurogenesis in the dentate gyrus and impaired short‐term memory in the novel object and passive avoidance tests. Taken together, our results indicate that alcohol causes deleterious effects in the adolescent brain which are distinct from those observed in adults. These data contribute to explain the greater sensitivity of the adolescent brain to alcohol toxicity.
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The effects of alcohol exposure were investigated on genes involved in oxidative mechanisms. In adolescent animals, alcohol decreased the expression of genes involved in DNA repair, a potential cause of the observed decrease of neurogenesis. In contrast, in the adult brain, alcohol increased the expression of genes associated with antioxidant mechanisms. Apoptosis was increase in all groups and converged with other biochemical alterations to enhance short‐term memory impairment in the adolescent brain. These data contribute to explain the greater sensitivity of the adolescent brain to alcohol toxicity.
Global Professional Service Firms and the Challenge of Institutional Complexity: ‘Field Relocation' as a Response Strategy
Authors: Faulconbridge James , Muzio Daniel 
Published: December 2014

ABSTRACTIn this paper we use the case of the internationalization of English law firms into Italy, and the refocusing of their operations on the city of Milan, to make a number of contributions to existing literatures on responses to institutional complexity. First, we contribute to the literature on how organizations address complexity at the field level, by revealing the role of ‘field relocation' as a particular response strategy. We also identify a number of organizational tactics – re‐scoping, re‐scaling, and re‐staffing – through which ‘field relocation' is accomplished. Second, we also show the importance of further developing our understanding of the geography of institutional fields by highlighting how the ‘receptivity' of different field locations may affect responses to complexity. This identifies the importance of geographically locating fields and sub‐fields in studies of organizational responses to institutional complexity.
Flexible working, work–family conflict, and maternal gatekeeping: The daily experiences of dual‐earner couples
Authors: Radcliffe Laura S. , Cassell Catherine 
Published: December 2014

This study explores the impact of flexible working on the daily experiences of work–family conflict for dual‐earner couples with child dependants. In exploring these daily experiences, the occurrence of maternal gatekeeping behaviours, and the relationship between flexible working and such behaviours is investigated. We draw on episodic and longitudinal data from qualitative diaries kept for a 1‐month period by both members of 24 couples (48 participants) as well as from introductory and subsequent in‐depth qualitative interviews with the couples, both together and apart. We report an evidence suggesting that work–family conflicts are experienced and resolved differently, depending on whether it is the male or the female who works flexibly within dual‐earner couples. This link between flexible working and gender is demonstrated to have an important impact on maternal gatekeeping behaviours, which are highlighted as playing a crucial role in such daily experiences and how they are resolved.Practitioner points

Traditional gender norms still play a role in parents' decisions to work flexibly and workers who opt for non‐traditional routes may feel stigmatized.

HR departments and employers need to promote the legitimacy of male access to flexible working and work–life balance policies, so these are not perceived as opportunities for mothers alone.

Greater father take‐up of work–life balance initiatives that offer more opportunities for involvement in childcare should be encouraged.

Employers should offer a variety of flexible working arrangements to provide employees with desirable and healthy resolution options when faced with incidents of work–family conflict.
The effects of human immunodeficiency virus infection on the expression of the drug efflux proteins P-glycoprotein and breast cancer resistance protein in a human intestine model
Authors: Ellis Kelstan , Marlin Jerry W , Taylor Tracey A H , Fitting Sylvia , Hauser Kurt F , Rice Greg , McRae MaryPeace 
Published: December 2014

Abstract

Objectives
In human immunodeficiency virus (HIV) infection, decreased penetration of antiretroviral drugs is postulated to contribute to HIV persistence within lymphoid-rich regions of the gastrointestinal (GI) tract. However, mechanistic explanations for this phenomenon remain unclear. Specifically, investigations of HIV effects on drug efflux proteins within intestinal models are minimal.

Methods
Using an in-vitro co-culture model of the GI tract, the effects of HIV infection on drug efflux proteins, P-glycoprotein and breast cancer resistance protein (BCRP) were evaluated. The influence of the HIV-1 protein, Tat, and oxidative stress on P-glycoprotein and BCRP was also evaluated.

Key findings
P-glycoprotein expression demonstrated an HIV-induced upregulation in Caco-2 cells over time for cells grown in co-culture with resting lymphocytes. BCRP overall expression increased with HIV exposure in activated primary human lymphocytes co-cultured with Caco-2 cells. Tat treatment resulted in no significant alterations in P-glycoprotein (43% increase), BCRP expression, or oxidative stress.

Conclusions
HIV exposure within an in-vitro intestinal model resulted in increases in P-glycoprotein and BCRP in a cell-specific manner. Additionally, observed changes were not mediated by Tat. Collectively, these results suggest that alterations in BCRP and P-glycoprotein may contribute, in part, to decreased antiretroviral concentrations within the gut-associated lymphoid tissue of the GI tract in HIV infection.
Essential oils and their constituents as skin penetration enhancer for transdermal drug delivery: a review
Authors: Herman Anna , Herman Andrzej P 
Published: December 2014

Abstract

Objectives
In this paper, we focused on essential oils and their constituents as skin penetration enhancers for transdermal drug delivery, mechanism of their action as well as their possible toxicity.

Key findings
Essential oils and their volatile constituents can penetrate through the skin as well as enhance penetration of different drug from topical formulation into the lower skin layers using different mechanisms of action based on (1) disintegration of the highly ordered intercellular lipid structure between corneocytes in stratum corneum, (2) interaction with intercellular domain of protein, which induces their conformational modification, (3) increase the partitioning of a drug. After application to the skin, essential oils and their components are rapidly metabolized, not accumulated in the organism and fast excreted what strongly suggest that they can be successfully use as safe penetration enhancers.

Summary
Essential oils and their constituents may be preferred over the traditionally used synthetics materials as safe and suitable permeation enhancers to promote the percutaneous absorption of hydrophilic and lipophilic drugs from topical formulation into the lower skin layers.
New thermosensitive nanoparticles prepared by biocompatible pegylated aliphatic polyester block copolymers for local cancer treatment
Authors: Karavelidis Vassilios , Bikiaris Dimitrios , Avgoustakis Konstantinos 
Published: December 2014

Abstract

Objective
New pegylated thermosensitive polymers were developed to study them as drug vehicles in targeting release nanoparticulate systems of anticancer drugs.

Methods
The drug vehicles were prepared in the form of core-shell nanoparticles using novel polymeric materials synthesized by copolymerization of poly(propylene adipate) (PPAd) and methoxy-polyethylene glycol (mPEG) with different molecular weights. The physical and chemical properties of the synthesized mPEG-PPAd copolymers were studied using several techniques, and their cytocompatibility was evaluated. For drug nanoencapsulation, a water in oil (W/O) emulsification and solvent evaporation technique was used and the prepared nanoparticles were studied for their physical properties, morphology, drug release and anticancer efficacy against cancer cell lines.

Key findings
The size of the nanoparticles lied in a range suitable for tumour targeting. Drug release was affected by the composition of polymer, the temperature and pH of the release medium. The release results obtained indicate that judicious selection of nanoparticles composition may allow for enhanced drug delivery to the tumours following application of local hyperthermia.

Conclusions
The paclitaxel-loaded mPEG-PPAd nanoparticles were found to be cytotoxic against to the human hepatoma HepG2) and the human epithelial (HeLa) cancer cell lines. Enhanced cytotoxicity against the HeLa cells was observed at elevated temperature (42°C compared with 37°C), providing support for the potential usefulness of the mPEG-PPAd nanoparticles for the development of thermo-sensitive anticancer drug delivery systems.
Developing accurate models of the human airways
Authors: Marshall Lindsay J , Oguejiofor Wilson , Willetts Rachel S , Griffiths Helen R , Devitt Andrew 
Published: December 2014

Abstract

Objectives
Particle delivery to the airways is an attractive prospect for many potential therapeutics, including vaccines. Developing strategies for inhalation of particles provides a targeted, controlled and non-invasive delivery route but, as with all novel therapeutics, in vitro and in vivo testing are needed prior to clinical use. Whilst advanced vaccine testing demands the use of animal models to address safety issues, the production of robust in vitro cellular models would take account of the ethical framework known as the 3Rs (Replacement, Reduction and Refinement of animal use), by permitting initial screening of potential candidates prior to animal use. There is thus a need for relevant, realistic in vitro models of the human airways.

Key findings
Our laboratory has designed and characterised a multi-cellular model of human airways that takes account of the conditions in the airways and recapitulates many salient features, including the epithelial barrier and mucus secretion.

Summary
Our human pulmonary models recreate many of the obstacles to successful pulmonary delivery of particles and therefore represent a valid test platform for screening compounds and delivery systems.
Synthesis and pharmacological evaluations of 4-hydroxycoumarin derivatives as a new class of anti-S
taphylococcus aureus agents
Authors: Li Zhou-peng , Li Jing , Qu Di , Hou Zheng , Yang Xiao-hui , Zhang Zi-dan , Wang Yu-kun , Luo Xiao-xing , Li Ming-kai 
Published: December 2014

Abstract

Objectives
Due to the increasing prevalence of drug-resistant Staphylococcus aureus infection, we develop novel 4-hydroxycoumarin derivatives as antimicrobials.

Methods
The antibacterial activity of 4-hydroxycoumarin derivatives against drug-susceptive S. aureus (ATCC 29213) and methicillin-resistant S. aureus (MRSA) were evaluated using minimal inhibitory concentration (MIC) assay; the activity of favourable compound was further observed using bacterial growth curves assay and in the MRSA infection mice.

Key findings
Compared with dihydropyran derivatives, compound 1 as one of biscoumarins showed most potent activity with MIC values of 4–8 μg/ml and apparently inhibited the growth rate of S. aureus ATCC 29213 and USA300 strain in concentrations of both 16 and 32 mg/ml. In the mice infected with MRSA USA300, administration of 5 mg/kg compound 1 improved the animal survival rate to 66.7%, and improved the pathological change in lung tissue compared with the infection model animals. No significant cytotoxicity of compound 1 was observed on the umbilical vein endothelial cells (HUVECs) under the concentration of 800 μg/ml.

Conclusion
Compared with the dihydropyran derivatives, biscoumarins exhibited more promising activity against both drug-sensitive and drug-resistant S. aureus, and it is efficacious in treating MRSA infections in mouse models with a favourable safety in human cells.
Filtering of plant functional traits is determined by environmental gradients and by past land use in a Mediterranean coastal marsh
Authors: Batriu Efrem , Ninot Josep Maria , Pino Joan 
Published: December 2014

AbstractQuestionWhat is the effect of past land use and environmental gradients on plant functional traits within coastal marsh plant communities?LocationMediterranean microtidal marshes in the Llobregat Delta, NE Spain.MethodsWe used a data set collected previously comprising 45 vegetation plots with associated soil parameters, water table conditions and past land use. For each species we obtained the values or states for a set of plant functional traits: plant height, leaf dry matter content, specific leaf area, seed production, seed weight, life form and lateral expansion. To account for the effect of phylogeny, we evaluated trait diversity skewness by means of an ultrametric phylogenetic tree specifically constructed for the species studied. The association between both environmental gradients and past disturbance, and plant functional traits was tested by means of RLQ analysis.ResultsOf all the traits, only seed weight showed a phylogenetic signal; consequently, phylogeny was not included in the RLQ analysis. Conductivity was negatively correlated with seed weight, whereas water table conditions and soil ionic balance were negatively correlated with specific leaf area. Past disturbance was negatively correlated with leaf dry matter content and with lateral expansion.ConclusionsPlant traits of Llobregat Delta coastal marsh communities are conditioned by environmental gradients and by past land use. Soil ionic balance and water table conditions determine key plant functional traits such as specific leaf area. This finding also corroborates the importance of soil ionic balance as a plant life driver in microtidal Mediterranean marshes. The effect of past land use on species traits might, however, be partially indirect and mediated by associated environmental changes.
Functional diversity reveals complex assembly processes on sea‐born volcanic islands
Authors: Karadimou Elpida , Tsiripidis Ioannis , Kallimanis Athanasios S. , Raus Thomas , Dimopoulos Panagiotis 
Published: December 2014

AbstractQuestionsDo the mechanisms driving community assembly differ between two islands of different age and history of vegetation development? How does sampling scale affect the strength that each assembly mechanism poses on the assembly of plant communities?LocationVolcanic islands (Palea Kameni and Nea Kameni) of Santorini Archipelago, Greece.MethodsFunctional diversity has been proposed as a framework for discriminating among mechanisms of community assembly, such as habitat filtering, limiting similarity and random assembly. We investigated four plant communities in two sea‐born volcanic islands. We recorded plant diversity at scales from 1 m2 to 64 m2. We calculated three indices of functional diversity: functional richness, functional evenness and functional divergence, using 26 functional traits (including vegetative characteristics, ecological preferences and regenerative characteristics). We used null model analysis to test for two different assembly mechanisms: habitat filtering and limiting similarity or random assembly.ResultsThe assemblage of the four communities was complex and did not follow a single mechanism. In most cases, finer‐scale patterns indicated randomness, while coarser scales revealed more structured communities. In the older island, the scrub community was mainly defined by limiting similarity. The therophytic community displayed a limited range of functional traits, indicating mainly habitat filtering, but within this range, the evenness of the distribution indicated limiting similarity. On the younger island, the range of traits did not differ from random. However, within this range of traits, one therophytic community showed signs of limiting similarity, while the second therophytic community displayed uneven functional trait distribution, indicating mainly habitat filtering. The three indices reflected different facets of functional diversity and were not correlated, thus we may argue that they are not redundant, and we even detected different mechanisms of assembly within the same community.ConclusionsThe functional diversity of the therophytic communities in the younger island implied no specific assembly mechanism; perhaps due to its age, the community is still at the early stages of colonization (i.e. stochastic processes, such as arrival of new species, prevail). In the older island, the lack of disturbances for a long period allowed the establishment of communities assembled by specific mechanisms, such as competition and habitat filtering.