bluuebunny/crossref_metadata_2025_split huggingface dataset:
Sensitivity of quantitative myocardial dynamic contrast‐enhanced MRI to saturation pulse efficiency, noise and t1 measurement error: Comparison of nonlinearity correction methods
Authors: Broadbent David A. , Biglands John D. , Ripley David P. , Higgins David M. , Greenwood John P. , Plein Sven , Buckley David L. 
Published: May 2015

PurposeTo compare methods designed to minimize or correct signal nonlinearity in quantitative myocardial dynamic contrast‐enhanced (DCE) MRI.MethodsDCE‐MRI studies were simulated and data acquired in eight volunteers. Signal nonlinearity was corrected using either a dual‐bolus approach or model‐based correction using proton‐density weighted imaging (conventional or dual‐sequence acquisition) or T1 data (native or bookend). Scanning of healthy and infarcted myocardium at 3 T was simulated, including noise, saturation imperfection and T1 measurement error. Data were analyzed using model‐based deconvolution with a one‐compartment (mono‐exponential) model.ResultsSubstantial variation between methods was demonstrated in volunteers. In simulations the dual‐bolus method proved stable for realistic levels of saturation efficiency but demonstrated bias due to residual nonlinearity. Model‐based methods performed ideally in the absence of confounding error sources and were generally robust to noise or saturation imperfection, except for native T1 based correction which was highly sensitive to the latter. All methods demonstrated large variation in accuracy above an over‐saturation level where baseline signal was nulled. For the dual‐sequence approach this caused substantial bias at the saturation efficiencies observed in volunteers.ConclusionThe choice of nonlinearity correction method in myocardial DCE‐MRI impacts on accuracy and precision of estimated parameters, particularly in the presence of nonideal saturation. Magn Reson Med 75:1290–1300, 2016. © 2015 Wiley Periodicals, Inc.
Non‐Cartesian balanced steady‐state free precession pulse sequences for real‐time cardiac MRI
Authors: Feng Xue , Salerno Michael , Kramer Christopher M. , Meyer Craig H. 
Published: May 2015

PurposeTo develop a new spiral‐in/out balanced steady‐state free precession (bSSFP) pulse sequence for real‐time cardiac MRI and compare it with radial and spiral‐out techniques.MethodsNon‐Cartesian sampling strategies are efficient and robust to motion and thus have important advantages for real‐time bSSFP cine imaging. This study describes a new symmetric spiral‐in/out sequence with intrinsic gradient moment compensation and SSFP refocusing at TE = TR/2. In vivo real‐time cardiac imaging studies were performed to compare radial, spiral‐out, and spiral‐in/out bSSFP pulse sequences. Furthermore, phase‐based fat/water separation taking advantage of the refocusing mechanism of the spiral‐in/out bSSFP sequence was also studied.ResultsThe image quality of the spiral‐out and spiral‐in/out bSSFP sequences was improved with off‐resonance and k‐space trajectory correction. The spiral‐in/out bSSFP sequence had the highest signal‐to‐noise ratio (SNR), contrast‐to‐noise ratio, and image quality ratings, with spiral‐out bSSFP sequence second in each category and the radial bSSFP sequence third. The spiral‐in/out bSSFP sequence provides separated fat and water images with no additional scan time.ConclusionsIn this study, a new spiral‐in/out bSSFP sequence was developed and tested. The superiority of spiral bSSFP sequences over the radial bSSFP sequence in terms of SNR and reduced artifacts was demonstrated in real‐time MRI of cardiac function without image acceleration. Magn Reson Med 75:1546–1555, 2016. © 2015 Wiley Periodicals, Inc.
The mediating effect of self‐efficacy in the relationship between social support and post‐traumatic stress disorder symptoms among patients with central system tumors in China: a cross‐sectional study
Authors: Wang Yang , Bao Yijun , Liu Li , Ramos Aaron , Wang Yunjie , Wang Lie 
Published: May 2015

AbstractBackgroundPost‐traumatic stress disorder (PTSD) is a disorder that can affect people following the experience of a traumatic event. Few studies have researched on PTSD symptoms of patients with central nervous system tumors. In this study, we aim to examine the association between social support and PTSD symptoms and to explore the mediating effect of self‐efficacy in this relationship among patients with central nervous system tumors in China.MethodsQuestionnaires consisting of the Post‐traumatic Stress Checklist‐ Civilian Version, the Duke‐UNC Functional Social Support Questionnaire, the General Self‐Efficacy Scale, as well as demographic and clinical factors were used to collect information of patients with central nervous system tumors in Liaoning Province, China. A total of 222 patients (effective response rate of 66.1%) became our subjects. Hierarchical linear regression analyses were performed to explore the association between social support and PTSD symptoms and the mediating effect of self‐efficacy.ResultsAfter adjusting for demographic characteristics and tumor type, social support was negatively associated with the total score of PTSD symptoms (β = −0.342, P < 0.01). Social support explained 8.8% of the variance in PTSD symptoms. Self‐efficacy was found to partially mediate the relationship between social support and PTSD symptoms.ConclusionsSelf‐efficacy partially mediated the relationship between social support and PTSD symptoms. Interventions focusing on both social support and self‐efficacy might be more useful than interventions only targeting either of them. Copyright © 2015 John Wiley & Sons, Ltd.
The Nrf2‐ARE pathway is associated with Schisandrin b attenuating benzo(a)pyrene‐Induced HTR cells damages in vitro
Authors: Dong Qulong , Hou Haiyan , Wu Jun , Chen Yaqiong 
Published: May 2015

ABSTRACTAs is ubiquitous in the environmental sources, benzo(a)pyrene (BaP) has been reported to induce reprotoxicity in previous studies. Toxicity to trophoblast cells may be one key factor, but evidences were absent. We speculated that BaP can induce cytotoxicity in human trophoblast HTR‐8/SVneo (HTR) cells, and Schisandrin B (Sch B) as a potential protector can inhibit the cytotoxicity. MTS assay identified that BaP induced HTR cells death while Sch B played a cytoprotective role. And after Nrf2 interference, the ability of Sch B‐induced cytoprotection was declined. Furthermore, PCR, western blot, ELISA, and SOD assays were found that Sch B significantly increased the mRNA and protein expression of Nrf2, HO1, NQO1, and SOD in the Nrf2‐ARE pathway, and the extents of increase were declined after Nrf2 interference. These results demonstrated that the Nrf2‐ARE pathway plays an important role in Sch B attenuating BaP‐induced HTR cells damages in vitro. © 2015 Wiley Periodicals, Inc. Environ Toxicol 31: 1439–1449, 2016.
Visible‐Light‐Driven Photocatalysts of Two Copper(II) Coordination Polymers with Rare Sulfonate and Imidazole Co‐Ligand System
Authors: Hou Xiang Yang , Wang Xiao , Wang Hao , Cao Jia , Fu Feng , Wang Ji Jiang , Gao Lou Jun 
Published: May 2015

AbstractTwo copper coordination polymers (CPs) [Cu(1,2‐BIYB)2(AQ‐2,6‐DA)]n·nH2O (1) and [Cu(1,4‐BIYB)2(AQ‐2,7‐DA)]n·3nH2O (2) were obtained by reactions of pentahydrate copper sulfate with corresponding sulfonate and imidazole ligand under hydrothermal conditions, respectively [Na2AQ‐2,7‐DA = anthraquinone‐2,7‐disulfonic acid disodium salt, Na2AQ‐2,6‐DA = anthraquinone‐2,6‐disulfonic acid disodium salt, 1,4‐BIYB = 1,4‐bis(imidazol‐1‐ylmethyl)benzene, 1,2‐BIYB = 1,2‐bis(imidazol‐1‐ylmethyl)benzene]. CPs 1 and 2 show different structures: CP 1 has a 2D architecture, which is further extended into a 3D supramolecular structure through hydrogen bonding interactions, whereas CP 2 has a 1D architecture, which generates a 3D supramolecular structure via hydrogen bonding and strong π···π interaction. Notably, CPs 1 and 2 feature rare examples of CPs based visible‐light‐driven photocatalysts and reveal good stability toward photocatalysis.
Do public health services in Egypt help young married women exercise their reproductive rights?
Authors: Abdel‐Tawab Nahla , Rabie Tamer , Boehmova Zuzana , Hawkins Loraine , Saher Sally , El Shitany Atef 
Published: May 2015

AbstractObjectiveTo assess supply and demand of family planning services from a reproductive rights perspective among young married women (YMW) in Egypt.MethodsData sources related to family planning included structured interviews with service providers (n = 216); an inventory of equipment and supplies (n = 40); exit interviews with YMW (n = 147); and focus group discussions (n = 12) with YMW, husbands, and mothers and/or mothers in law. YMW, husbands and mothers in law were not necessarily related.ResultsAlthough family planning services were readily available and affordable, YMW had limited access to information and services. Shortfalls were noted regarding respect for privacy, choice of family planning method, access to fertility services, and premarital counseling. Few YMW had sufficient autonomy to make informed reproductive decisions. Effective accountability mechanisms and processes for redress were also lacking.ConclusionImplementation of a rights‐based approach and structural changes to family planning service delivery are recommended to empower YMW in Egypt to demand and exercise their reproductive rights.
Cross agency priority goals in the U.S. government: Can directed collaboration be a stepping stone toward politic-centered performance?
Authors: Putansu Steven R 
Published: May 2015

AbstractThe typical problems associated with performance management are particularly evident as the complexity of policy issues increases. “Wicked” policy areas with cross-cutting responsibilities, uncertain solutions, and constantly evolving problems are strongly subject to the pathology of the rational-scientific approach. One effort the U.S. government is making to mitigate these limitations is the designation of some of these areas as cross-agency priority goals. In theory, directed collaboration among the multiple agencies responsible will bring different perspectives, definitions, and potential solutions to the surface, and will allow for a critical and iterative approach toward measurement of performance toward the policy goal. However, history has shown that performance efforts have a tendency to return to the pathologies of the rational-scientific chain. This article examines three of these goals: climate change, cybersecurity, and Science, Technology, Engineering and Math (STEM) education, and considers the extent to which requiring collaboration in performance management results in increased adoption of the political-realistic chain of performance management.
Plate waste and intake of school lunch based on the new Nordic diet and on packed lunches: a randomised controlled trial in 8- to 11-year-old Danish children
Authors: Thorsen Anne V. , Lassen Anne D. , Andersen Elisabeth W. , Christensen Lene M. , Biltoft-Jensen Anja , Andersen Rikke , Damsgaard Camilla T. , Michaelsen Kim F. , Tetens Inge 
Published: May 2015

AbstractThe aim of the present study was to compare total food intake, total and relative edible plate waste and self-reported food likings between school lunch based on the new Nordic diet (NND) and packed lunch from home. In two 3-month periods in a cluster-randomised controlled unblinded cross-over study 3rd- and 4th-grade children (n187) from two municipal schools received lunch meals based on NND principles and their usual packed lunch (control). Food intake and plate waste (n1558) were calculated after weighing lunch plates before and after the meal for five consecutive days and self-reported likings (n905) assessed by a web-based questionnaire. Average food intake was 6 % higher for the NND period compared with the packed lunch period. The quantity of NND intake varied with the menu (P< 0·0001) and was positively associated with self-reported likings. The edible plate waste was 88 (sd80) g for the NND period and 43 (sd60) g for the packed lunch period whereas the relative edible plate waste was no different between periods for meals having waste (n1050). Edible plate waste differed between menus (P< 0·0001), with more waste on soup days (36 %) and vegetarian days (23 %) compared with the packed lunch period. Self-reported likings were negatively associated with percentage plate waste (P< 0·0001). The study suggests that portion sizes need to be considered in new school meal programmes. New strategies with focus on reduction of plate waste, children's likings and nutritious school meals are crucial from both a nutritional, economic and environmental point of view.
Delineating site-specific management zones for precision agriculture
Authors: FARID H. U. , BAKHSH A. , AHMAD N. , AHMAD A. , MAHMOOD-KHAN Z. 
Published: May 2015

SUMMARYDelineating site-specific management zones within fields can be helpful in addressing spatial variability effects for adopting precision farming practices. A 3-year (2008/09 to 2010/11) field study was conducted at the Postgraduate Agricultural Research Station, University of Agriculture, Faisalabad, Pakistan, to identify the most important soil and landscape attributes influencing wheat grain yield, which can be used for delineating management zones. A total of 48 soil samples were collected from the top 300 mm of soil in 8-ha experimental field divided into regular grids of 24 × 67 m prior to sowing wheat. Soil and landscape attributes such as elevation, % of sand, silt and clay by volume, soil electrical conductivity (EC), pH, soil nitrogen (N) and soil phosphorus (P) were included in the analysis. Artificial neural network (ANN) analysis showed that % sand, % clay, elevation, soil N and soil EC were important variables for delineating management zones. Different management zone schemes ranging from three to six were developed and evaluated based on performance indicators using Management Zone Analyst (MZA V0·1) software. The fuzziness performance index (FPI) and normalized classification entropy NCE indices showed minimum values for a four management zone scheme, indicating its appropriateness for the experimental field. The coefficient of variation values of soil and landscape attributes decreased for each management zone within the four management zone scheme compared to the entire field, which showed improved homogeneity. The evaluation of the four management zone scheme using normalized wheat grain yield data showed distinct means for each management zone, verifying spatial variability effects and the need for its management. The results indicated that the approach based on ANN and MZA software analysis can be helpful in delineating management zones within the field, to promote precision farming practices effectively.
FRAMEWORK FOR USER INVOLVEMENT IN HEALTH TECHNOLOGY ASSESSMENT AT THE LOCAL LEVEL: VIEWS OF HEALTH MANAGERS, USER REPRESENTATIVES, AND CLINICIANS
Authors: Gagnon Marie-Pierre , Desmartis Marie , Gagnon Johanne , St-Pierre Michèle , Rhainds Marc , Coulombe Martin , Tantchou Mylène Dipankui , Légaré France 
Published: May 2015

Objectives: The aim of this study was to explore stakeholders’ points of views regarding the applicability and relevance of a framework for user involvement in health technology assessment (HTA) at the local level. We tested this framework in the context of the assessment of alternative measures to restraint and seclusion among hospitalized adults and those living in long-term-care facilities.Methods: Twenty stakeholders (health managers, user representatives, and clinicians) from seven regions of Quebec participated in a semi-structured interview. A thematic analysis of the transcribed interviews was performed.Results: The findings highlighted the relevance and applicability of the framework to this specific HTA. According to interviewees, direct participation of users in the HTA process allows them to be part of the decision-making process. User consultation makes it possible to consider the views of a wide variety of people, such as marginalized and vulnerable groups, who do not necessarily meet the requirements for participating in HTA committees. However, some user representatives emphasized that user consultation should be integrated into a more holistic and participatory perspective. The most frequent barrier associated with user involvement in HTA was the top-down health system, which takes little account of the user's perspective.Conclusions: The proposed framework was seen as a reference tool for making practitioners and health managers aware of the different mechanisms of user involvement in HTA and providing a structured way to classify and describe strategies. However, there is a need for more concrete instruments to guide practice and support decision making on specific strategies for user involvement in HTA at the local level.
L’évaluation de la mémoire rétrograde dans la population Québécoise âgée: Le PUB-40 et le PUB-12
Authors: Langlois Roxane , Joubert Sven , Benoit Sophie , Dostie Valérie , Rouleau Isabelle 
Published: May 2015

ABSTRACTMemory assessment represents an important part of the clinical neuropsychologist’s duties in a geriatric context. In fact, in Canada, about one-third of seniors report memory complaints, with different causes. Based on the underlying etiology, different components of memory may be affected in older adults. Nonautobiographical retrograde memory (public or semantic) is an important aspect of memory to assess; nevertheless, there is currently no reliable and standardized clinical tool to evaluate this aspect of memory in the elderly Quebecer population. The aims of this research were therefore: (1) to develop a protocol specifically aimed at assessing non-autobiographical retrograde memory in this population, the PUB-40; (2) to obtain reference data among 105 healthy subjects; and (3) to develop a short version based on the items which discriminated a group of 20 patients with amnestic Mild cognitive impairment (aMCI) from older healthy subjects.
Methylation of exons 1D, 1F, and 1Hof the glucocorticoid receptor gene promoter and exposure to adversity in preschool-aged children
Authors: Tyrka Audrey R. , Parade Stephanie H. , Eslinger Nicole M. , Marsit Carmen J. , Lesseur Corina , Armstrong David A. , Philip Noah S. , Josefson Brittney , Seifer Ronald 
Published: May 2015

AbstractEpigenetic modifications to the genome are a key mechanism involved in the biological encoding of experience. Animal studies and a growing body of literature in humans have shown that early adversity is linked to methylation of the gene for the glucocorticoid receptor (GR), which is a key regulator of the hypothalamic–pituitary–adrenal axis as well as a broad range of physiological systems including metabolic and immune function. One hundred eighty-four families participated, includingn= 74 with child welfare documentation of moderate-severe maltreatment in the past 6 months. Children ranged in age from 3 to 5 years, and were racially and ethnically diverse. Structured record review and interviews in the home were used to assess a history of maltreatment, other traumas, and contextual life stressors, and a composite variable assessed the number exposures to these adversities. Methylation of regions 1D, 1F, and 1Hof the GR gene was measured via sodium bisulfite pyrosequencing. The composite measure of adversity was positively correlated with methylation at exons 1Dand 1Fin the promoter of the GR gene. Individual stress measures were significantly associated with a several CpG sites in these regions. GR gene methylation may be a mechanism of the biobehavioral effects of adverse exposures in young children.
Multi-level dynamo and opinion spreading
Authors: BRUNETTI SARA , CORDASCO GENNARO , LODI ELENA , GARGANO LUISA , QUATTROCIOCCHI WALTER 
Published: May 2015

We consider the following multi-level opinion spreading model on networks. Initially, each node gets a weight, from the set {0,. . .,k – 1}, which measures the individual conviction of a new idea or product. Then, by proceeding in rounds, each node updates its weight according to those of its neighbours. We study k-dynamos that are initial assignments of weights leading each node to get the value k – 1 – e.g. unanimous maximum level of acceptance – within a given number of rounds; the goal is to minimize the sum of the initial weights of the nodes. We determine lower bounds on the sum of the initial weights under the irreversible simple majority rules, where a node increases its weight if and only if the majority of its neighbours have a weight that is higher than its own. We study the relations among 2-dynamos and k-dynamos, with and without a bound on the number of rounds needed to reach the desired all-(k – 1) configuration. Moreover, we provide constructive tight upper bounds for some classes of regular topologies: rings, tori and cliques.
Spatially and temporally resolved gas distributions around heterogeneous catalysts using infrared planar laser-induced fluorescence
Authors: Zetterberg Johan , Blomberg Sara , Gustafson Johan , Evertsson Jonas , Zhou Jianfeng , Adams Emma C. , Carlsson Per-Anders , Aldén Marcus , Lundgren Edvin 
Published: May 2015

AbstractVisualizing and measuring the gas distribution in close proximity to a working catalyst is crucial for understanding how the catalytic activity depends on the structure of the catalyst. However, existing methods are not able to fully determine the gas distribution during a catalytic process. Here we report on how the distribution of a gas during a catalytic reaction can be imaged in situ with high spatial (400 μm) and temporal (15 μs) resolution using infrared planar laser-induced fluorescence. The technique is demonstrated by monitoring, in real-time, the distribution of carbon dioxide during catalytic oxidation of carbon monoxide above powder catalysts. Furthermore, we demonstrate the versatility and potential of the technique in catalysis research by providing a proof-of-principle demonstration of how the activity of several catalysts can be measured simultaneously, either in the same reactor chamber, or in parallel, in different reactor tubes.
Perovskite–fullerene hybrid materials suppress hysteresis in planar diodes
Authors: Xu Jixian , Buin Andrei , Ip Alexander H. , Li Wei , Voznyy Oleksandr , Comin Riccardo , Yuan Mingjian , Jeon Seokmin , Ning Zhijun , McDowell Jeffrey J. , Kanjanaboos Pongsakorn , Sun Jon-Paul , Lan Xinzheng , Quan Li Na , Kim Dong Ha , Hill Ian G. , Maksymovych Peter , Sargent Edward H. 
Published: May 2015

AbstractSolution-processed planar perovskite devices are highly desirable in a wide variety of optoelectronic applications; however, they are prone to hysteresis and current instabilities. Here we report the first perovskite–PCBM hybrid solid with significantly reduced hysteresis and recombination loss achieved in a single step. This new material displays an efficient electrically coupled microstructure: PCBM is homogeneously distributed throughout the film at perovskite grain boundaries. The PCBM passivates the key PbI3− antisite defects during the perovskite self-assembly, as revealed by theory and experiment. Photoluminescence transient spectroscopy proves that the PCBM phase promotes electron extraction. We showcase this mixed material in planar solar cells that feature low hysteresis and enhanced photovoltage. Using conductive AFM studies, we reveal the memristive properties of perovskite films. We close by positing that PCBM, by tying up both halide-rich antisites and unincorporated halides, reduces electric field-induced anion migration that may give rise to hysteresis and unstable diode behaviour.