bluuebunny/crossref_metadata_2025_split huggingface dataset:
Effect of Phosphate Salt Concentration and Solution pH on the Aqueous‐Phase Homo and Copolymerization of N‐Vinyl Pyrrolidone
Authors: Borges Fernando T. P. , Papavasiliou Georgia , Murad Sohail , Teymour Fouad 
Published: May 2018

Abstract
N‐vinyl pyrrolidone (NVP) aqueous‐phase polymerization is known to depend on the degree of hydration of the NVP molecules, resulting in an increase in the rate of propagation with decreasing monomer concentration. When potassium monophosphate and sodium hexametaphosphate are added to the monomer solution the reaction kinetics slow down, with the degree of retardation being dependent on salt‐to‐monomer concentration ratio. Using polymerization reaction models in combination with ion coordination theory, this effect can be associated with an active interaction of the ions in solution with the NVP molecules. When varying the solution pH, an optimum operating zone ranging approximately from pH 4 to pH 7 for the NVP–V‐50 2,2′‐Azobis(2‐methylpropionamidine) dihydrochloride (AAPH) system is found. Potassium persulfate is unable to initiate NVP homopolymerization. The addition of poly(ethylene glycol) diacrylate as a comonomer reduces the kinetic slow‐down caused by the addition of salts or by extreme pH and significantly increases the overall conversion rate.
Synthesis of Cyclic (Ethylene Furanoate) Oligomers via Cyclodepolymerization
Authors: Fleckenstein Peter , Rosenboom Jan‐Georg , Storti Giuseppe , Morbidelli Massimo 
Published: May 2018

AbstractHigh molecular weight polyethylene furanoate (PEF) is a potential replacement for polyethylene terephthalate. Ring‐opening‐polymerization of PEF can represent a viable alternative to the classical polycondensation process, provided that a synthesis route is available to supply high purity cycles in high yields. In this work, cyclic oligomers of PEF are produced by cyclodepolymerization (CDP). Reactions are performed in different high boiling solvents and 2‐methylnaphthalene (2‐MN) is chosen as a favorable reaction solvent for a detailed analysis of the reaction equilibrium behavior of cyclic and linear PEF. Such equilibrium can be described by the well‐known model of Jacobson and Stockmayer. The corresponding equilibrium constants are first determined by fitting a set of equilibrium data. Based on this description of the reaction, a kinetic model is then developed and validated by comparison with experimental data. Finally, selective precipitation is shortly explored as a practical purification method which, together with CDP, can enable a large scale process for the production of high purity cyclic PEF oligomers for ring‐opening‐polymerization.
Perceived images and expected roles of Indonesian nurses
Authors: Sommers Christine L. , Tarihoran Dame Elysabeth , Sembel Sandra , Tzeng Huey‐Ming 
Published: May 2018

AbstractAimThe aim of this study was to explore how non‐nurses and nurses differ regarding the perceived images and expected roles of Indonesian nurses.DesignA cross‐sectional survey studyMethodsAn online tool shared via email was used to collect data in March 2014, from a convenient sample of 1,228 employees of a private university located in Karawaci, Indonesia. An English/Indonesian version of the survey was developed: 19 perception items and 19 expectation items using a 5‐point Likert scale. Independent sample t tests were used to compare groups.ResultsOne hundred and forty‐three people completed the survey; a response rate of 11.6%. Thirteen were nurses and 130 were non‐nurses. Compared with nurses, non‐nurses were less likely to agree with statements that Indonesian nurses are self‐sacrificing, provide help to others, are devoted to caring, perform housekeeping duties and are knowledgeable. Monitoring nurses' image on a regular basis is essential. A public education campaign could focus on selected positive characteristics to improve the image of Indonesian nurses.
Effect of polyethylene glycol plasticizer on long‐term antibacterial activity and the release profile of bacteriocin nisin from polylactide blends
Authors: Holcapkova Pavlina , Hurajova Anna , Kucharczyk Pavel , Bazant Pavel , Plachy Tomas , Miskolczi Norbert , Sedlarik Vladimir 
Published: May 2018

This work describes the synergetic effect of polyethylene glycol (PEG) in polylactide (PLA) blends, wherein the polyether acts as both the plasticizer and functional additive, ensuring the long‐term antimicrobial activity of bacteriocin nisin. Two types of PEG with the molecular weights of 1000 and 6000 g.mol−1(20 wt.%) were used to plasticize the PLA blends. The aforementioned bacteriocin nisin, at concentrations ranging between 0.02 and 0.15 wt.% (8000‐60 000 IU.g−1), was incorporated into the samples by the solvent cast technique. The effect of various PEG on the structural, mechanical, and thermal properties of the PLA‐based blends were investigated by scanning electron microscopy, Fourier transform infrared spectroscopy, stress‐strain analysis, differential scanning calorimetry, and dynamic mechanical analysis, respectively. The antibacterial activity of the samples was detected by the agar diffusion technique againstMicrococcus luteus. Furthermore, the antibacterial properties of the samples were tested according the ISO 22196 standard against Gram‐negative (Escherichia coli) and Gram‐positive (Staphylococcus aureus,Listeria monocytogenes) bacterial strains. The nisin was detected by high performance liquid chromatography, the device having been equipped with a UV/vis detector. The results show that the PEG, besides its plasticizing effect, significantly enhances the release profile and sustains long‐term antibacterial activity of nisin in a PLA matrix.
Photoswitchable double bonds: Synthetic strategies for tunability and versatility
Authors: Cameron David , Eisler Sara 
Published: May 2018

AbstractIsomerizations of azo, imine, and alkene groups using light are highly tunable. As such, photoswitches based on these functional groups have become critical components of many responsive molecules and materials. This mini‐review describes recent work focused on controlling various properties of double bond‐based molecular switches, including speed of switching, thermal stability, and wavelength required to initiate switching. Methods used to control structure and function vary, but commonly involve careful probing of the electronic, photochemical, and steric profiles of the molecular switches. Successes and avenues for further investigation will be discussed.
Predicting nonadherence to adjuvant endocrine therapy in women with early stage breast cancer
Authors: Corter Arden L. , Broom Reuben , Porter David , Harvey Vernon , Findlay Michael 
Published: May 2018

AbstractBackgroundFailing to take endocrine therapy (ET) as prescribed (nonadherence) increases risk of morbidity and mortality from breast cancer recurrence. We explored predictors of nonadherence, including demographic, clinical, treatment, and personal factors, among women newly prescribed ET for early stage breast cancer. We also examined predictors of their thoughts about stopping treatment (TST).MethodsA baseline survey prior to ET assessed demographics, illness beliefs, beliefs about medicines, fear of recurrence, symptoms, and negative affect. A follow‐up survey at 3 months repeated these measures with additional questions about nonadherence and TST. Nonadherence and TST were analyzed using logistic and multiple regression, respectively. Patient record review provided clinical data. The baseline survey was completed by 125 women, with a 96% retention rate at follow‐up.ResultsThirty‐six percent reported nonadherence, and 30% reported TST. Results of regression analyses showed that TST was most strongly associated with symptom severity at follow‐up, whereas, lower coherence beliefs, and the absence of comorbid conditions were the strongest predictors of actual nonadherence.ConclusionThis is the first longitudinal study to examine concurrently the association of demographic, personal and treatment factors with nonadherence, and TST. Findings have potentially important clinical implications; interventions to improve adherence and reduce TST may need to target women's understanding of their diagnosis and treatment, illness beliefs, and symptoms prior to starting therapy.
Prediction of plastic film thickness based on gas permeability and validation with ‘Kyoho’ table grapes for optimal modified atmosphere packaging
Authors: Chen Shoujiang , Wang Haiou , Fu Qingquan , Wang Rongrong , Zhang Wei , Cai Xiaoning 
Published: May 2018

Modified atmosphere packaging (MAP) storage has become a useful technique for extending the shelf life of fruit and vegetables. However, the success of MAP depends on many factors, including types of fresh products, storage conditions, and the characteristics of the packaging films. To achieve the optimal gas composition in the package headspace and improve the postharvest quality of fresh produce, the packaging film with appropriate barrier properties needs to be selected. This study aimed to predict the film thickness by applying produce respiration rate and package film permeability data measured in given product weight and storage conditions. An available film (eg, 25‐μm‐thick low‐density polyethylene) was used to pack fresh produce, and the respiration rate of fresh produce and in‐package O2 and CO2 concentrations at steady state were measured. Permeability of the film was calculated based on mass balance, and the thickness of the film could be predicted if the recommended target O2 and CO2 concentration was obtained from the literature. To validate the predicted thickness value, an experiment was conducted by packaging fresh table grapes in bags of the predicted thickness. The effect of packaging with different film thicknesses on the quality of the fruit was determined. The results showed good agreement between the predicted and the experimental in‐bag O2 and CO2 concentrations, and the MAP with predicted thickness (90 μm) film was more effective in maintaining postharvest quality of grapes during low‐temperature storage than the thinner films (30 and 60 μm) and the control.
Use of native macrophytes for recovery of the habitat structure and complexity of a lowland stream affected by river engineering works: Implications for management
Authors: Paz L.E. , Nicolosi Gelis M.M. , Licursi M. , Gómez N. , Rodrigues Capítulo A. 
Published: May 2018

AbstractMacrophytes were transplanted into a lowland stream affected by river engineering works. The aim was to analyse the feasibility of their reintroduction and potential to be used for the recovery of the structure and complexity of the lotic habitat. Macrophytes contribute heterogeneity to streams, modify the current velocity, affect sediment and nutrients dynamics, and provide a substrate for epiphytic biofilm. We transplanted specimens of Ludwigia peploides, Gymnocoronis spilanthoides, and Egeria densa into a stream located in the Pampean plain (Buenos Aires, Argentina). The growth and coverage of the transplanted macrophytes and the changes in the structure of the epiphytic biofilm were assessed. The results show that specimens of G. spilanthoides were negatively affected by the transplant and new conditions, E. densa decreased its coverage after the transplant, and L. peploides endured the transplant and adapted to the dredging site with successful establishment and expansion. There were no significant differences between the biofilm developed in L. peploides and G. spilanthoides. Additionally, the biofilm had similar features between the transplanted macrophytes and those from a site with no dredging. Considering this result, the selection between these macrophytes in relation to biofilm production is indifferent. However, as L. peploides adapts better to the new conditions generated by the river engineering works, its use in the rehabilitation project is recommended. Moreover, it is important to consider the ability of different species of macrophytes to survive the transplant and grow under new environmental conditions in order to include them in rehabilitation projects.
Reduced complexity satellite broadcast receiver with interference mitigation in correlated noise
Authors: Abu‐Shaban Zohair , Mehrpouyan Hani , M. R. Bhavani Shankar , Ottersten Björn 
Published: May 2018

SummaryThe recent commercial trends towards using smaller dish antennas for satellite receivers and the growing density of broadcasting satellites necessitate the application of robust adjacent satellite interference cancellation schemes. This orbital density growth along with the wider beamwidth of a smaller dish have imposed an overloaded scenario at the satellite receiver, where the number of transmitting satellites exceeds the number of receiving elements at the dish antenna. To ensure successful operation in this practical scenario, we propose a satellite receiver that enhances signal detection from the desired satellite by mitigating the interference from neighboring satellites. Towards this objective, we propose an enhanced list‐based group‐wise search detection (E‐LGSD) receiver under the assumption of spatially correlated additive noise. To further enhance detection performance, the proposed satellite receiver utilizes a newly designed whitening filter to remove the spatial correlation among the noise parameters, while also applying a preprocessor that maximizes the signal‐to‐interference‐plus‐noise ratio. We exploit the structure of this filter and propose a reduced complexity LGSD (RC‐LGSD) receiver. Extensive simulations under practical scenarios show that the proposed receiver enhances the performance of satellite broadcast systems in the presence of adjacent satellite interference compared with existing methods. Also, under pointing error, RC‐LGSD exhibits similar behavior to that of the optimum receiver.
Economizing Production of Diverse 2D Layered Metal Hydroxides for Efficient Overall Water Splitting
Authors: Zheng Zongmin , Lin Lele , Mo Shiguang , Ou Daohui , Tao Jing , Qin Ruixuan , Fang Xiaoliang , Zheng Nanfeng 
Published: May 2018

Abstract2D layered metal hydroxides (LMH) are promising materials for electrochemical energy conversion and storage. Compared with exfoliation of bulk layered materials, wet chemistry synthesis of 2D LMH materials under mild conditions still remains a big challenge. Here, an “MgO‐mediated strategy” for mass production of various 2D LMH nanosheets is presented by hydrolyzing MgO in metal salt aqueous solutions at room temperature. Benefiting from this economical and scalable strategy, ultrathin LMH nanosheets (M = Ni, Fe, Co, NiFe, and NiCo) and their derivatives (e.g., metal oxides and sulfides) can be synthesized in high yields. More importantly, this strategy opens up opportunities to fabricate hierarchically structured LMH nanosheets, resulting in high‐performance electrocatalysts for the oxygen‐ and hydrogen‐evolution reactions to realize stable overall water splitting with a low cell voltage of 1.55 V at 10 mA cm−2. This work provides a powerful platform for the synthesis and applications of 2D materials.
3D PtFe Clusters with Cube‐in‐Cube Structure Enhance Oxygen Reduction Catalysis and Electrochemical Sensing
Authors: Lin Fei , Sun Yingjun , Lai Jianping , Wang Kai , Tang Yonghua , Chao Yuguang , Yang Yong , Feng Jianrui , Lv Fan , Zhou Peng , Huang Minghua , Guo Shaojun 
Published: May 2018

AbstractRational design and construction of high‐performance electrocatalytic nanomaterials is significant for improving activity and stability of oxygen reduction reaction (ORR), and the sensitivity and selectivity of electrochemical sensors. Herein, the synthesis of a class of PtFe clusters with a cube‐in‐cube structure (PtFe‐CIC) is reported. The nanoscale PtFe clusters are constructed by primary subunits of the nanocube and have porous structure and high surface area. The PtFe‐CIC exhibits much enhanced electrocatalytic activity for ORR by showing high specific activity and mass activity. The PtFe‐CIC is a highly universal and efficient electrocatalyst for boosting the electrocatalysis of H2O2 and hydrazine to construct high‐sensitivity sensors in 0.1 m phosphate‐buffered saline solution. The as‐prepared PtFe‐CIC shows a wide detection range of 2 × 10−9 to 1.5 × 10−3m for H2O2 with a very low detection limit of 0.7 × 10−9m, and a wide linear range of 0.1–357.9 × 10−6m for hydrazine with a very low detection limit of 33 × 10−9m. This work opens a new way to design 3D superarchitectures with porous structure for boosting electrocatalysis of small molecules.
APOE‐ε4 associates with hippocampal volume, learning, and memory across the spectrum of Alzheimer's disease and dementia with Lewy bodies
Authors: Saeed Usman , Mirza Saira S. , MacIntosh Bradley J. , Herrmann Nathan , Keith Julia , Ramirez Joel , Nestor Sean M. , Yu Qinggang , Knight Jo , Swardfager Walter , Potkin Steven G. , Rogaeva Ekaterina , St. George‐Hyslop Peter , Black Sandra E. , Masellis Mario 
Published: May 2018

AbstractIntroductionAlthough the apolipoprotein E ε4‐allele (APOE‐ε4) is a susceptibility factor for Alzheimer's disease (AD) and dementia with Lewy bodies (DLB), its relationship with imaging and cognitive measures across the AD/DLB spectrum remains unexplored.MethodsWe studied 298 patients (AD = 250, DLB = 48; 38 autopsy‐confirmed; NCT01800214) using neuropsychological testing, volumetric magnetic resonance imaging, and APOE genotyping to investigate the association of APOE‐ε4 with hippocampal volume and learning/memory phenotypes, irrespective of diagnosis.ResultsAcross the AD/DLB spectrum: (1) hippocampal volumes were smaller with increasing APOE‐ε4 dosage (no genotype × diagnosis interaction observed), (2) learning performance as assessed by total recall scores was associated with hippocampal volumes only among APOE‐ε4 carriers, and (3) APOE‐ε4 carriers performed worse on long‐delay free word recall.DiscussionThese findings provide evidence that APOE‐ε4 is linked to hippocampal atrophy and learning/memory phenotypes across the AD/DLB spectrum, which could be useful as biomarkers of disease progression in therapeutic trials of mixed disease.
Economic Development through Treaty Reparations in New Zealand and Canada
Authors: Tait Myra J. , Ladner Kiera L. 
Published: May 2018

AbstractIn Canada, Treaty 1 First Nations brought a claim against the Crown for land debt owed to them since 1871. In 2004, Crown land in Winnipeg became available that, according to the terms of the settlement, should have been offered for purchase to Treaty 1 Nations. Similarly, in New Zealand, the Waikato-Tainui claim arose from historical Crown breaches of the 1840 Treaty of Waitangi. In 1995, a settlement was reached to address the unjust Crown confiscation of Tainui lands. Despite being intended to facilitate the return of traditional territory, compensate for Crown breaches of historic treaties, and indirectly provide opportunity for economic development, in both cases, settlement was met with legal and political challenges. Using a comparative legal analysis, this paper examines how the state continues to use its law-making power to undermine socio-economic development of Indigenous communities in Canada and New Zealand, thereby thwarting opportunity for Indigenous self-determination.
Seasonal Variation in the Correlation Between Anomalies of Sea Level and Chlorophyll in the Antarctic Circumpolar Current
Authors: Song Hajoon , Long Matthew C. , Gaube Peter , Frenger Ivy , Marshall John , McGillicuddy Dennis J. 
Published: May 2018

AbstractThe Antarctic Circumpolar Current has highly energetic mesoscale phenomena, but their impacts on phytoplankton biomass, productivity, and biogeochemical cycling are not understood well. We analyze satellite observations and an eddy‐rich ocean model to show that they drive chlorophyll anomalies of opposite sign in winter versus summer. In winter, deeper mixed layers in positive sea surface height (SSH) anomalies reduce light availability, leading to anomalously low chlorophyll concentrations. In summer with abundant light, however, positive SSH anomalies show elevated chlorophyll concentration due to higher iron level, and an iron budget analysis reveals that anomalously strong vertical mixing enhances iron supply to the mixed layer. Features with negative SSH anomalies exhibit the opposite tendencies: higher chlorophyll concentration in winter and lower in summer. Our results suggest that mesoscale modulation of iron supply, light availability, and vertical mixing plays an important role in causing systematic variations in primary productivity over the seasonal cycle.
Strongly Anisotropic Magnesiowüstite in Earth's Lower Mantle
Authors: Finkelstein Gregory J. , Jackson Jennifer M. , Said Ayman , Alatas Ahmet , Leu Bogdan M. , Sturhahn Wolfgang , Toellner Thomas S. 
Published: May 2018

AbstractThe juxtaposition of a liquid iron‐dominant alloy against a mixture of silicate and oxide minerals at Earth's core‐mantle boundary is associated with a wide range of complex seismological features. One category of observed structures is ultralow‐velocity zones, which are thought to correspond to either aggregates of partially molten material or solid, iron‐enriched assemblages. We measured the phonon dispersion relations of (Mg,Fe) O magnesiowüstite containing 76 mol % FeO, a candidate ultralow‐velocity zone phase, at high pressures using high‐energy resolution inelastic X‐ray scattering. From these measurements, we find that magnesiowüstite becomes strongly elastically anisotropic with increasing pressure, potentially contributing to a significant proportion of seismic anisotropy detected near the base of the mantle.
Critical Zone Structure Under a Granite Ridge Inferred From Drilling and Three‐Dimensional Seismic Refraction Data
Authors: Flinchum Brady A. , Steven Holbrook W. , Rempe Daniella , Moon Seulgi , Riebe Clifford S. , Carr Bradley J. , Hayes Jorden L. , St. Clair James , Peters Marc Philipp 
Published: May 2018

AbstractObserving the critical zone (CZ) below the top few meters of readily excavated soil is challenging yet crucial to understanding Earth surface processes. Near‐surface geophysical methods can overcome this challenge by imaging the CZ in three dimensions (3‐D) over hundreds of meters, thus revealing lateral heterogeneity in subsurface properties across scales relevant to understanding hillslope erosion, weathering, and biogeochemical cycling. We imaged the CZ under a soil‐mantled ridge developed in granitic terrain of the Laramie Range, Wyoming, using data from five boreholes and a 3‐D volume (970 by 600 by 80 m) of seismic velocities generated by ordinary kriging of 25 two‐dimensional seismic refraction transects. The observed CZ structure under the ridge broadly matches predictions of two recently proposed hypotheses: the uppermost surface of weathered bedrock is consistent with subsurface weathering driven by bedrock drainage and subsurface topography defining the top of unweathered protolith is consistent with fracturing predicted from topographic and regional stresses. In contrast, differences in slope aspect along the ridge are too subtle to explain observed variations in regolith structure. Our observations suggest that multiple processes, each of which may dominate at different depths, work in concert to regulate deep CZ structure.