bluuebunny/crossref_metadata_2025_split huggingface dataset:
Impact of overlying water velocity on ammonium uptake by benthic biofilms
Authors: Arnon Shai , Yanuka Keren , Nejidat Ali 
Published: February 2012

AbstractThe effect of the overlying water velocity on ammonium (NH4+) uptake by benthic biofilms was studied in a recirculating laboratory flume (260 cm long, 29 cm wide), packed with 5 cm of silica sand arranged into bedforms. NH4+ uptake was determined as the reduction in NH4+ concentration in the water at average overlying water velocities of 0.8, 2, 4 and 8 cm s−1. NH4+ uptake was relatively constant under laminar flow conditions but increased when the flow regime became turbulent (>4 cm s−1). This pattern was observed for two biofilms differing in their total biomass and in the abundance of the ammonia‐oxidizing bacteria, thus indicating that NH4+ uptake was strongly controlled by mass‐transfer processes. The near stoichiometric relationship between the rates of NH4+ uptake and nitrate (NO3−) accumulation suggests that aerobic nitrification was the main route for NH4+ uptake. Microelectrode measurements showed a sharp decline of oxygen concentrations and pH values within the biofilms, thus supporting strong nitrification activity within the surficial section of the benthic biofilms. The results of this study highlight the key role of hydrodynamic conditions in regulating NH4+ uptake in the transition from laminar to turbulent flow conditions. Copyright © 2012 John Wiley & Sons, Ltd.
Dendrohydroclimate reconstructions of July–August runoff for two nival‐regime rivers in west central British Columbia
Authors: Starheim Colette C. A. , Smith Dan J. , Prowse Terry D. 
Published: February 2012

AbstractLengthy records of river discharge are necessary to comprehensively assess the long‐term connection between synoptic climate forcings and nival‐regime systems in British Columbia. A regional multispecies network of tree‐ring width and ring density chronologies was built for west central British Columbia with the intention of dendrohydrologically extending short runoff records in this area. Extended records of July–August mean discharge anomalies for the Skeena and Atnarko Rivers were reconstructed back to ad 1660. Low flow events represented during the late 1600s, early 1700s and late 1800s lie beyond those experienced during the recent instrumental period for these basins. The documentation of extreme events of this magnitude necessitates consideration when planning for future water resources in this region.Supplementary dendroclimatic reconstructions of the winter Pacific North American (PNA) pressure anomaly pattern and records of mean summer temperature and end‐of‐winter snow water equivalent were also constructed. These ancillary climate records provide insight into the long‐term climate drivers of annual discharge dynamics within these nival basins. Correlation and wavelet analyses confirm the persistent relationship of synoptic climate regimes described by the Southern Oscillation Index, NINO 3.4, Pacific Decadal Oscillation and PNA indices on runoff in west central British Columbia. Copyright © 2012 John Wiley & Sons, Ltd.
Regional thinning of cerebral cortical thickness in first‐episode and chronic schizophrenia
Authors: Kim June Sic , Chung Chun Kee , Jo Hang Joon , Lee Jong Min , Kown Jun Soo 
Published: February 2012

AbstractFirst‐episode schizophrenia and chronic schizophrenia have different patterns of cortical gray matter loss, due to differences in the period of illness. Differences in the reduction of cortical thickness between first‐episode and chronic schizophrenia has not yet been addressed using a technique of measuring cortical thickness. The goal of this study is to identify differences in cerebral cortical thickness between first‐episode schizophrenic patients and matched normal controls as well as between chronic schizophrenic patients and matched normal controls. Thirty‐five chronic and 24 first‐episode schizophrenic patients were compared with each age‐ and sex‐matched control group, respectively. To measure cortical thickness, we utilized an inner and outer cortical surface reconstruction algorithm. Cortical thickness was directly measured as the distance between the two surfaces. Statistical analysis was performed with diffusion smoothing along cortical manifolds, and surface normalization on a sphere model. There were no significant changes in global mean thickness and cerebral gray matter volume in both first‐episode and chronic schizophrenia patients. However, we observed regional thinning of cortical thickness, most significantly in the superior temporal gyrus of first‐episode schizophrenic patients. In chronic schizophrenia, larger regions including the prefrontal cortex (PF) were significantly thinned compared to the first‐episode group. This suggests that the duration of illness affects cortical thinning in the PF, as well as the extent of cortical thinning. © 2012 Wiley Periodicals, Inc. Int J Imaging Syst Technol, 22, 73–80, 2012
Enhancement of osteogenesis by poly(lactide‐co‐glycolide) sponges loaded with surface‐embedded hydroxyapatite particles and rhBMP‐2
Authors: Li Dan , Ye Chen , Zhu Yang , Gou Zhongru , Gao Changyou 
Published: February 2012

AbstractThe bone mesenchymal stem cells (BMSCs) were seeded on [poly(lactide‐co‐glycolide) scaffolds with hydroxyapatite (HA) coating, and “s” stands for surface] (PLGA/HA‐S), PLGA/HA‐M (containing the same HA amount in the matrix as that of the PLGA/HA‐S and “m” stands for matrix), and PLGA scaffolds, which were then cultured in a medium‐containing Escherichia coli‐derived recombinant human bone morphogenetic protein‐2 (ErhBMP‐2). In vitro culture of rat BMSCs found no different cell morphology in all the scaffolds, but the alkaline phosphatase activity and osteogenic gene expression of type I collagen (COL I) and osteocalcin (OCN) in the PLGA/HA‐S scaffolds were always highest and were significantly improved in comparison with those in the PLGA scaffolds. In a rat calvarial defect model, new bone formation was enhanced in the PLGA/HA‐S/ErhBMP‐2 implants at 4 and 8 weeks after implantation too. Therefore, the PLGA/HA‐S scaffold can better enhance the ErhBMP‐2‐induced osteogenic differentiation of BMSCs in vitro and osteogenesis in vivo. © 2012 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 2012.
Multi‐color palette of fluorescent proteins for imaging the tumor microenvironment of orthotopic tumorgraft mouse models of clinical pancreatic cancer specimens
Authors: Suetsugu Atsushi , Katz Matthew , Fleming Jason , Truty Mark , Thomas Ryan , Moriwaki Hisataka , Bouvet Michael , Saji Shigetoyo , Hoffman Robert M. 
Published: February 2012

AbstractPancreatic‐cancer‐patient tumor specimens were initially established subcutaneously in NOD/SCID mice immediately after surgery. The patient tumors were then harvested from NOD/SCID mice and passaged orthotopically in transgenic nude mice ubiquitously expressing red fluorescent protein (RFP). The primary patient tumors acquired RFP‐expressing stroma. The RFP‐expressing stroma included cancer‐associated fibroblasts (CAFs) and tumor‐associated macrophages (TAMs). Further passage to transgenic nude mice ubiquitously expressing green fluorescent protein (GFP) resulted in tumors that acquired GFP stroma in addition to their RFP stroma, including CAFs and TAMs as well as blood vessels. The RFP stroma persisted in the tumors growing in the GFP mice. Further passage to transgenic nude mice ubiquitously expressing cyan fluorescent protein (CFP) resulted in tumors acquiring CFP stroma in addition to persisting RFP and GFP stroma, including RFP‐ and GFP‐expressing CAFs, TAMs and blood vessels. This model can be used to image progression of patient pancreatic tumors and to visually target stroma as well as cancer cells and to individualize patient therapy. J. Cell. Biochem. 113: 2290–2295, 2012. © 2012 Wiley Periodicals, Inc.
Role of spastin and protrudin in neurite outgrowth
Authors: Zhang Chuanling , Li Dan , Ma Yan , Yan Jinting , Yang Baiqing , Li Peng , Yu Aiping , Lu Cailing , Ma Xu 
Published: February 2012

AbstractHereditary spastic paraplegia (HSP) is a neurodegenerative disorder characterized by retrograde axonal degeneration that primarily affects long spinal neurons. The gene encoding spastin has a well‐established association with HSP, and protrudin is a known binding partner of spastin. Here, we demonstrate that theN‐terminal domain of protrudin mediates the interaction with spastin, which is responsible for neurite outgrowth. We show that spastin promotes protrudin‐dependent neurite outgrowth in PC12 cells. To further confirm these physiological functions in vivo, we microinjected zebrafish embryos with various protrudin/spastin mRNA and morpholinos. The results suggest that the spinal cord motor neuron axon outgrowth of zebrafish is regulated by the interaction between spastin and protrudin. In addition, the putative HSP‐associated protrudinG191V mutation was shown to alter the subcellular distribution and impair the yolk sac extension of zebrafish, but without significant defects in neurite outgrowth both in PC12 cells and zebrafish. Taken together, our findings indicate that protrudin interacts with spastin and induces axon formation through itsN‐terminal domain. Moreover, protrudin and spastin may work together to play an indispensable role in motor axon outgrowth. J. Cell. Biochem. 113: 2296–2307, 2012. © 2012 Wiley Periodicals, Inc.
Defining and measuring the effort needed for inpatient medicine work
Authors: Lamba Reema , Schapira Marilyn M. , Singh Siddhartha , Fletcher Kathlyn E. 
Published: February 2012

AbstractBACKGROUND:Current metrics for assessing physician workload are inadequate. Understanding the effort associated with work tasks could make workload assessments more robust.OBJECTIVE:To assess the physical, mental, and psychological effort needed for the tasks performed by internal medicine doctors while admitting a patient to the hospital.DESIGN:Cross‐sectional survey.SETTING:A single Midwest academic institution.SUBJECTS:Internal medicine housestaff, hospitalists, and nonhospitalist internal medicine faculty.MEASUREMENTS:Subjects rated 99 tasks across 3 domains: physical, mental, and psychological effort using a scale of 1–7 (1 = least effort, 7 = most effort). A composite effort score was calculated for each task and for each of 6 task categories: direct patient care, indirect patient care, searching for/finding things, educational/academic activities, personal/downtime activities, and other.RESULTS:Overall, the most difficult task was going to codes, which was also the most difficult psychological task. The most difficult physical task was placing a central line, and the most difficult mental task was transferring an unstable patient to the intensive care unit. The easiest task was using the Internet. That was also the easiest physical, mental, and psychological task. Direct patient care was more difficult than indirect patient care overall (3.58 vs 3.21; P < 0.001).CONCLUSION:We began the process of describing the workload of inpatient doctors by measuring the difficulty of the tasks they perform while admitting patients. To assess the relationship between workload and other outcomes (such as physician burnout and patient safety), it is essential that we be able to accurately measure workload. Journal of Hospital Medicine 2012. © 2012 Society of Hospital Medicine
Magnetic resonance elastography as a method to estimate myocardial contractility
Authors: Kolipaka Arunark , Aggarwal Shivani R. , McGee Kiaran P. , Anavekar Nandan , Manduca Armando , Ehman Richard L. , Araoz Philip A. 
Published: February 2012

AbstractPurpose:To determine whether increasing epinephrine infusion in an in vivo pig model is associated with an increase in end‐systolic magnetic resonance elastography (MRE)‐derived effective stiffness.Materials and Methods:Finite element modeling (FEM) was performed to determine the range of myocardial wall thicknesses that could be used for analysis. Then MRE was performed on five pigs to measure the end‐systolic effective stiffness with epinephrine infusion. Epinephrine was continuously infused intravenously in each pig to increase the heart rate in increments of 20%. For each such increase end‐systolic effective stiffness was measured using MRE. In each pig, Student's t‐test was used to compare effective end‐systolic stiffness at baseline and at initial infusion of epinephrine. Least‐square linear regression was performed to determine the correlation between normalized end‐systolic effective stiffness and increase in heart rate with epinephrine infusion.Results:FEM showed that phase gradient inversion could be performed on wall thickness ≈≥1.5 cm. In pigs, effective end‐systolic stiffness significantly increased from baseline to the first infusion in all pigs (P = 0.047). A linear correlation was found between normalized effective end‐systolic stiffness and percent increase in heart rate by epinephrine infusion with R2 ranging from 0.86–0.99 in four pigs. In one of the pigs the R2 value was 0.1. A linear correlation with R2 = 0.58 was found between normalized effective end‐systolic stiffness and percent increase in heart rate when pooling data points from all pigs.Conclusion:Noninvasive MRE‐derived end‐systolic effective myocardial stiffness may be a surrogate for myocardial contractility. J. Magn. Reson. Imaging 2012;36:120–127. © 2012 Wiley Periodicals, Inc.
Discounting in International Markets and the Face Value Effect: A Double‐ Edged Sword?
Authors: Lowe Ben , Barnes Bradley R. , Rugimbana Robert 
Published: February 2012

ABSTRACTConsumer response to price is often subjective and prone to systematic perceptual biases, such as the “face value” effect, whereby consumer perceptions of willingness to pay are systematically biased by the nominal value of a new currency. That is, prices presented in higher denomination currencies are perceived to be more expensive and prices presented in lower denomination currencies are perceived to be less expensive. The results from two separate experiments suggest that for high‐price products, when a substantial enough discount is invoked, the face value effect can reverse and becomes a double‐edged sword. While existing research implies that the face value effect becomes stronger for high‐price products, the findings from this research suggest this is the case only when the product is not being promoted. The findings also reveal that the face value effect is robust for low‐price products, even when there is a discount, providing further evidence of the effect in new contexts. Consistent with earlier research, this is because in real terms the discount for a low‐price product is not perceived as substantial enough. The experiments also suggest that for high‐price products, discounts framed as absolute amounts in higher denomination currencies are perceived to be more substantial than discounts framed as percentage amounts. These findings extend existing theory on the face value effect and have several important managerial implications for pricing management in international markets.
In Search of the “Meta‐Maven”: An Examination of Market Maven Behavior across Real‐Life, Web, and Virtual World Marketing Channels
Authors: Barnes Stuart J. , Pressey Andrew D. 
Published: February 2012

ABSTRACTRecently, a new set of channels for consumer and business interaction have emerged—three‐ dimensional “virtual” worlds. This study attempts to better understand the nature of market maven behavior (diffusers of general marketplace and shopping information) across three different channels—virtual worlds, the Web, and real‐life—and to examine the extent to which market maven behavior is transferable across channel context (i.e., “fluid”) or channel dependent. Using data from two surveys (one in the virtual world “Second Life” and a follow‐up Web survey for the same respondents), this paper explores differences and determinants of maven behavior. Employing partial least squares analysis, the findings indicate that market maven propensity is transferable across channels (i.e., high‐scoring market mavens retain this across channel). However, while there may be the transferability of market maven behavior across channels, the findings demonstrate that maven propensity is influenced by the channel context. Consequently, individuals with high maven propensity tend to exhibit channels in which this behavior is more prominent. Therefore, market maven behavior might not only span general product categories, but also the channel itself (i.e., maven behavior remains fairly constant—or fluid—across channel). The findings also point to possible characteristics that may be used in the identification of market mavens: market mavens typically have greater cognizance of other mavens, are technology‐savvy and individualistic, are of either gender and tend to be older and more intensive and experienced users of Web platforms and also intensive users of virtual worlds than those with low maven propensity. The findings of the study contribute to understanding market maven behavior, and provide an insight into the practices of mavens in a multichannel context, particularly in the case of the emerging channels that are virtual worlds.
Comparing localized and nonlocalized dynamic 31P magnetic resonance spectroscopy in exercising muscle at 7T
Authors: Meyerspeer Martin , Robinson Simon , Nabuurs Christine I. , Scheenen Tom , Schoisengeier Adrian , Unger Ewald , Kemp Graham J. , Moser Ewald 
Published: February 2012

AbstractBy improving spatial and anatomical specificity, localized spectroscopy can enhance the power and accuracy of the quantitative analysis of cellular metabolism and bioenergetics. Localized and nonlocalized dynamic 31P magnetic resonance spectroscopy using a surface coil was compared during aerobic exercise and recovery of human calf muscle. For localization, a short echo time single‐voxel magnetic resonance spectroscopy sequence with adiabatic refocusing (semi‐LASER) was applied, enabling the quantification of phosphocreatine, inorganic phosphate, and pH value in a single muscle (medial gastrocnemius) in single shots (TR = 6 s). All measurements were performed in a 7 T whole body scanner with a nonmagnetic ergometer. From a series of equal exercise bouts we conclude that: (a) with localization, measured phosphocreatine declines in exercise to a lower value (79 ± 7% cf. 53 ± 10%, P = 0.002), (b) phosphocreatine recovery shows shorter half time (t1/2 = 34 ± 7 s cf. t1/2 = 42 ± 7 s, nonsignificant) and initial postexercise phosphocreatine resynthesis rate is significantly higher (32 ± 5 mM/min cf. 17 ± 4 mM/min, P = 0.001) and (c) in contrast to nonlocalized 31P magnetic resonance spectroscopy, no splitting of the inorganic phosphate peak is observed during exercise or recovery, just an increase in line width during exercise. This confirms the absence of contaminating signals originating from weaker‐exercising muscle, while an observed inorganic phosphate line broadening most probably reflects variations across fibers in a single muscle. Magn Reson Med, 2012. © 2012 Wiley Periodicals, Inc.
Two‐grid methods for time‐harmonic Maxwell equations
Authors: Zhong Liuqiang , Shu Shi , Wang Junxian , Xu J. 
Published: February 2012

SUMMARYIn this paper, we develop several two‐grid methods for the Nédélec edge finite element approximation of the time‐harmonic Maxwell equations. We first present a two‐grid method that uses a coarse space to solve the original problem and then use a fine space to solve a corresponding symmetric positive definite problem. Then, we present two types of iterative two‐grid methods, one is to add the kernel of the curl‐operator in the fine space to a coarse mesh space to solve the original problem and the other is to use an inner iterative method for dealing with the kernel of the curl‐operator in the fine space and the coarse space, separately. We provide the error estimates for the first two methods and present numerical experiments to show the efficiency of our methods.Copyright © 2012 John Wiley & Sons, Ltd.
A risk to himself: Attitudes toward psychiatric patients and choice of psychosocial strategies among nurses in medical–surgical units
Authors: MacNeela Pádraig , Scott P. Anne , Treacy Margaret , Hyde Abbey , O'Mahony Rebecca 
Published: February 2012

AbstractPsychiatric patients are liable to stereotyping by healthcare providers. We explored attitudes toward caring for psychiatric patients among 13 nurses working in general hospitals in Ireland. Participants thought aloud in response to a simulated patient case and described a critical incident of a patient for whom they had cared. Two attitudinal orientations were identified that correspond to stereotypical depictions of risk and vulnerability. The nurses described psychosocial care strategies that were pragmatic rather than authentically person‐centered, with particular associations between risk‐oriented attitudes and directive nursing care. Nurses had expectations likely to impede relationship building and collaborative care. Implications arising include the need for improved knowledge about psychiatric conditions and for access to professional development in targeted therapeutic communication skills. © 2012 Wiley Periodicals, Inc. Res Nurs Health 35:200–213, 2012
Excellent boron emitter passivation for high‐efficiency Si wafer solar cells using AlOx/SiNx dielectric stacks deposited in an industrial inline plasma reactor
Authors: Duttagupta Shubham , Lin Fen , Shetty Kishan Devappa , Aberle Armin G. , Hoex Bram 
Published: February 2012

ABSTRACTExcellent passivation of boron emitters is realised using AlOx/SiNx dielectric stacks deposited in an industrial inline plasma‐enhanced chemical vapour deposition reactor. Very low emitter saturation current density (J0e) values of 10 and 45 fA/cm2 are obtained for 180 and 30 Ω/sq planar p+ emitters, respectively. For textured p+ emitters, the J0e was found to be 1.5–2 times higher compared with planar emitters. The required thermal activation of the AlOx films is performed in a standard industrial fast‐firing furnace, making the developed passivation stack industrially viable. We also show that an AlOx thickness of 5 nm in the AlOx/SiNx stack is sufficient for obtaining a J0e of 18 fA/cm2 for planar 80 Ω/sq p+ emitters, which corresponds to a 1‐sun open‐circuit voltage limit of the solar cell of 736 mV at 25 °C. Copyright © 2012 John Wiley & Sons, Ltd.