bluuebunny/crossref_metadata_2025 huggingface dataset:
Size-dependences of the dielectric and ferroelectric properties of BaTiO3/polyvinylidene fluoride nanocomposites
Authors: Mao Y. P. , Mao S. Y. , Ye Z.-G. , Xie Z. X. , Zheng L. S.
Published: July 2010

Composites containing pure, uniform, and well-dispersed ferroelectric barium titanate (BaTiO3) nanocrystallites with various particle sizes as active phase and polyvinylidene fluoride (PVDF) polymer as matrix are fabricated using a two-step mixing and hot-pressing technique. The dependences of the dielectric and ferroelectric properties of the as-prepared composites on the nanoparticle sizes are investigated systematically. The polarization-electric field hysteresis loops are displayed, indicating the ferroelectricity for the BaTiO3/PVDF nanocomposites. The remanent polarization is found to increase as the size of BaTiO3 particles increases from 25 to 500 nm. The dielectric constant of the composites exhibits a complex variation as a function of the BaTiO3 nanoparticle sizes: it reaches a maximum value in the composites with BaTiO3 nanoparticle sizes of 80–100 nm and decreases again when the particle size is further reduced under 50 nm.
Tracking the catalyzed growth process of nanowires by in situ x-ray diffraction
Authors: Kirkham Melanie , Wang Zhong Lin , Snyder Robert L.
Published: July 2010

Quasi-one-dimensional nanostructures of silicon, oxides, and other materials show great promise for a variety of applications. These nanostructures are commonly grown using metal catalyst nanoparticles. This paper investigates the growth mechanism of Au-catalyzed Si nanowires through in situ x-ray diffraction, and the results are compared to previously studied Au-catalyzed ZnO nanorods. The Si nanowires were found to grow from molten catalyst particles, however, the ZnO nanorods were found to grow from solid catalyst particles through a surface diffusion process. From this comparison, the relative bonding types of the catalyst and source material are determined to have a significant effect on the growth mechanism.
Multicomponent wavefield characterization with a novel scanning laser interferometer
Authors: Blum Thomas E. , van Wijk Kasper , Pouet Bruno , Wartelle Alexis
Published: July 2010

The in-plane component of the wavefield provides valuable information about media properties from seismology to nondestructive testing. A new compact scanning laser ultrasonic interferometer collects light scattered away from the angle of incidence to provide the absolute ultrasonic displacement for both the out-of-plane and an in-plane components. This new system is tested by measuring the radial and vertical polarization of a Rayleigh wave in an aluminum half-space. The estimated amplitude ratio of the horizontal and vertical displacement agrees well with the theoretical value. The phase difference exhibits a small bias between the two components due to a slightly different frequency response between the two processing channels of the prototype electronic circuitry.
Hysteresis and unusual magnetic properties in the singular Heusler alloy Ni45Co5Mn40Sn10
Authors: Srivastava Vijay , Chen Xian , James Richard D.
Published: July 2010

The alloy Ni45Co5Mn40Sn10 is shown to be singular relative to nearby alloys in three following ways: (1) The austenite has remarkably high magnetization (1170 emu/cm3) and low magnetic anisotropy. (2) The thermal hysteresis is near minimum. (3) The transformation temperature ∼135 °C is unusually high. Because the unusually large magnetization and low hysteresis is seen at relatively small applied fields, applications such as magnetic shape memory, energy conversion, and solid state refrigeration may become practical.
Nitrogen doped MgxZn1−xO/ZnO single heterostructure ultraviolet light-emitting diodes on ZnO substrates
Authors: Nakahara K. , Akasaka S. , Yuji H. , Tamura K. , Fujii T. , Nishimoto Y. , Takamizu D. , Sasaki A. , Tanabe T. , Takasu H. , Amaike H. , Onuma T. , Chichibu S. F. , Tsukazaki A. , Ohtomo A. , Kawasaki M.
Published: July 2010

We have grown nitrogen-doped MgxZn1−xO:N films on Zn-polar ZnO single crystal substrates by molecular beam epitaxy. As N-sources, we employed NO-plasma or NH3 gas itself. As x increased, optimum growth temperature window for smooth film morphology shifted to higher temperatures, while maintaining high N-concentration (∼1×1019 cm−3). The heterosructures of MgxZn1−xO:N (0.1≤x≤0.4)/ZnO were fabricated into light emitting diodes of 500-μm-diameter. We observed ultraviolet near-band-edge emission (λ∼382 nm) with an output power of 0.1 μW for a NO-plasma-doped LED and 70 μW for a NH3-doped one at a bias current of 30 mA.
Influence of tetragonal distortion on the magnetic and electronic properties of the Heusler compound Co2TiSn from first principles
Authors: Meinert Markus , Schmalhorst Jan-Michael , Reiss Günter
Published: July 2010

Using the full potential linearized augmented plane wave plus local orbitals method we determine ab initio the lattice parameters of tetragonally distorted Co2TiSn in the L21 structure. The tetragonal lattice parameter c is determined as a function of the lattice parameter a by energy minimization. The change in total energy is found to be only a few kBT with respect to room temperature. The spin polarizations as well as the magnetizations are stable against small lattice distortions. It is shown, that the volume is not constant upon distortion and that the volume change is related with significant changes in the magnetization and the gap energy.
Color tunable light-emitting diodes based on p+-Si/p-CuAlO2/n-ZnO nanorod array heterojunctions
Authors: Ling Bo , Zhao Jun Liang , Sun Xiao Wei , Tan Swee Tiam , Kyaw Aung Ko Ko , Divayana Yoga , Dong Zhi Li
Published: July 2010

Wide-range color tuning from red to blue was achieved in phosphor-free p+-Si/p-CuAlO2/n-ZnO nanorod light-emitting diodes at room temperature. CuAlO2 films were deposited on p+-Si substrates by sputtering followed by annealing. ZnO nanorods were further grown on the annealed p+-Si/p-CuAlO2 substrates by vapor phase transport. The color of the p-CuAlO2/n-ZnO nanorod array heterojunction electroluminescence depended on the annealing temperature of the CuAlO2 film. With the increase of the annealing temperature from 900 to 1050 °C, the emission showed a blueshift under the same forward bias. The origin of the blueshift is related to the amount of Cu concentration diffused into ZnO.
Removal of floating dust in glow discharge using plasma jet
Authors: Ticoş C. M. , Jepu I. , Lungu C. P. , Chiru P. , Zaroschi V. , Lungu A. M.
Published: July 2010

Dust can be an inconvenient source of impurities in plasma processing reactors and in many cases it can cause damage to the plasma-treated surfaces. A technique for dust expulsion out of the trapping region in plasma is presented here, based on the wind force exerted on dust particles by a pulsed plasma jet. Its applicability is demonstrated by removing floating dust in the sheath of parallel-plate capacitive radio-frequency plasma.
Agronomy looking forward, thinking broadly
Authors: Titmarsh I. J. , Doughton J. , Woods E.
Published: July 2010

Global trends in human population and agriculture dictate that future calls made on the resources (physical, human, financial) and systems involved in producing food will be increasingly more demanding and complex. Both plant breeding and improved agronomy lift the potential yield of crops, a key component in progressing farm yield, so society can reasonably expect both agronomy as a science and agronomists as practitioners to contribute to the successful delivery of necessary change. By reflecting on current trends in agricultural production (diversification, intensification, integration, industrialisation, automation) and deconstructing a futuristic scenario of attempting agricultural production on Mars, it seems the skills agronomists will require involve not only the mandatory elements of their discipline but also additional skills that enable engagement with, even leadership of, teams who integrate (in sum or part) engineering, (agri-)business, economics and operational management, and build the social capital required to create and maintain a diverse array of enhanced and new ethical production systems and achieve increasing efficiencies within them.
B cell depletion reduces the development of atherosclerosis in mice
Authors: Ait-Oufella Hafid , Herbin Olivier , Bouaziz Jean-David , Binder Christoph J. , Uyttenhove Catherine , Laurans Ludivine , Taleb Soraya , Van Vré Emily , Esposito Bruno , Vilar José , Sirvent Jérôme , Van Snick Jacques , Tedgui Alain , Tedder Thomas F. , Mallat Ziad
Published: July 2010

B cell depletion significantly reduces the burden of several immune-mediated diseases. However, B cell activation has been until now associated with a protection against atherosclerosis, suggesting that B cell–depleting therapies would enhance cardiovascular risk. We unexpectedly show that mature B cell depletion using a CD20-specific monoclonal antibody induces a significant reduction of atherosclerosis in various mouse models of the disease. This treatment preserves the production of natural and potentially protective anti–oxidized low-density lipoprotein (oxLDL) IgM autoantibodies over IgG type anti-oxLDL antibodies, and markedly reduces pathogenic T cell activation. B cell depletion diminished T cell–derived IFN-γ secretion and enhanced production of IL-17; neutralization of the latter abrogated CD20 antibody–mediated atheroprotection. These results challenge the current paradigm that B cell activation plays an overall protective role in atherogenesis and identify new antiatherogenic strategies based on B cell modulation.
The minimal volume orientable hyperbolic 2-cusped 3-manifolds
Authors: Agol Ian
Published: July 2010

We prove that the Whitehead link complement and the

(
−
2
,
3
,
8
)

(-2,3,8)

pretzel link complement are the minimal volume orientable hyperbolic 3-manifolds with two cusps, with volume

3.66...
3.66...

= 4

×
\times

Catalan’s constant. We use topological arguments to establish the existence of an essential surface which provides a lower bound on volume and strong constraints on the manifolds that realize that lower bound.
Odd harmonic numbers exceed 10²⁴
Authors: Cohen Graeme , Sorli Ronald
Published: July 2010

A numbern>1n>1is harmonic ifσ(n)∣nτ(n)\sigma (n)\mid n\tau (n), whereτ(n)\tau (n)andσ(n)\sigma (n)are the number of positive divisors ofnnand their sum, respectively. It is known that there are no odd harmonic numbers up to101510^{15}. We show here that, for any odd numbern>106n>10^6,τ(n)≤n1/3\tau (n)\le n^{1/3}. It follows readily that ifnnis odd and harmonic, thenn>p3a/2n>p^{3a/2}for any prime power divisorpap^aofnn, and we have used this in showing thatn>1018n>10^{18}. We subsequently showed that for any odd numbern>9⋅1017n>9\cdot 10^{17},τ(n)≤n1/4\tau (n)\le n^{1/4}, from which it follows that ifnnis odd and harmonic, thenn>p8a/5n>p^{8a/5}withpap^aas before, and we use this improved result in showing thatn>1024n>10^{24}.
On a family of Thue equations of degree 16
Authors: Ziegler Volker
Published: July 2010

We consider a parameterized family of Thue equations of degree

16
16

. By reducing this family to a system of Pell equations and linear relations, we are able to solve this family.
Unified primal formulation-based a priori and a posteriori error analysis of mixed finite element methods
Authors: Vohralík Martin
Published: July 2010

We derive in this paper a unified framework for a priori and a posteriori error analysis of mixed finite element discretizations of second-order elliptic problems. It is based on the classical primal weak formulation, the postprocessing of the potential proposed in [T. Arbogast and Z. Chen, On the implementation of mixed methods as nonconforming methods for second-order elliptic problems, Math. Comp. 64 (1995), 943–972], and the discrete Friedrichs inequality. Our analysis in particular avoids any explicit use of the uniform discrete

inf
\inf

–

sup
\sup

condition and in a straightforward manner and under minimal necessary assumptions, known convergence and superconvergence results are recovered. The same framework then turns out to lead to optimal a posteriori energy error bounds. In particular, estimators for all families and orders of mixed finite element methods on grids consisting of simplices or rectangular parallelepipeds are derived. They give a guaranteed and fully computable upper bound on the energy error, represent error local lower bounds, and are robust under some conditions on the diffusion–dispersion tensor. They are thus suitable for both overall error control and adaptive mesh refinement. Moreover, the developed abstract framework and a posteriori error estimates are quite general and apply to any locally conservative method. We finally prove that in parallel and simultaneously in converse to Galerkin finite element methods, under some circumstances, the weak solution is the orthogonal projection of the postprocessed mixed finite element approximation onto the

H
0
1

(
Ω
)

H^1_0(\Omega )

space and also establish several links between mixed finite element approximations and some generalized weak solutions.
Whole Grains and Digestive Health
Authors: Slavin Joanne
Published: July 2010

Whole grains contain all parts of the grain: the endosperm, germ, and bran. Whole grains are rich in fermentable carbohydrates that reach the gut: dietary fiber, resistant starch, and oligosaccharides. Most research that supports the importance of grains to gut health was conducted with isolated fiber fractions, rather than whole grains. Whole grains are an important source of dietary fiber and grain fibers such as wheat, oats, barley, and rye increase stool weight, speed intestinal transit, get fermented to short chain fatty acids, and modify the gut microflora. Wheat bran is particularly effective in increasing stool weight; wheat bran increases stool weight by a ratio of 5:1. In contrast, many novel fibers that are easily incorporated into beverages and foods increase stool weight only on a ratio of 1:1. In vitro fermentation studies with whole grains have been published. Carbohydrates of oat bran (rich in β‐glucan) were consumed by bacteria faster than those of rye and wheat brans (rich in arabinoxylan). Grain fibers were fermented more slowly than inulin, causing less gas production. Wheat is particularly high in fructo‐oligosaccharides, while wheat germ is high in raffinose oligosaccharides. Some in vivo studies show the prebiotic potential of whole grains. Whole grain breakfast cereal was more effective than wheat bran breakfast cereal as a prebiotic, increasing fecal bifidobacteria and lactobacilli in human subjects. Wheat bran consumption increased stool frequency. Thus, the gut enhancing effects of cereal fibers are well known. Limited data exist that whole grains alter gut health.
Physicochemical Properties and In Vitro Starch Digestibility of Cooked Rice from Commercially Available Cultivars in Canada
Authors: Chung Hyun‐Jung , Liu Qiang , Huang Ruilin , Yin Yulong , Li Aike
Published: July 2010

The influence of amylose content, cooking, and storage on starch structure, thermal behaviors, pasting properties, and rapidly digestible starch (RDS), slowly digestible starch (SDS), and resistant starch (RS) in different commercial rice cultivars was investigated. Long grain rice with high‐amylose content had a higher gelatinization temperature and a lower gelatinization enthalpy than the other rice cultivars with intermediate amylose content (Arborio and Calrose) and waxy type (glutinous). The intensity ratio of 1047/1022 cm–1 determined by Fourier Transform Infrared (FT‐IR), which indicated the ordered structure in starch granules, was the highest in glutinous and the lowest in long grain. Results from Rapid ViscoAnalyser (RVA) showed that the rice cultivar with higher amylose content had lower peak viscosity and breakdown, but higher pasting temperature, setback, and final viscosity. The RDS content was 28.1, 38.6, 41.5, and 57.5% in long grain, Arborio, Calrose, and glutinous rice, respectively, which was inversely related to amylose content. However, the SDS and RS contents were positively correlated with amylose content. During storage of cooked rice, long grain showed a continuous increase in pasting viscosity, while glutinous exhibited the sharp cold‐water swelling peak. The retrogradation rate was greater in rice cultivars with high amylose content. The ratio of 1047/1022 cm–1 was substantially decreased by cooking and then increased during storage of cooked rice due to the crystalline structure, newly formed by retrogradation. Storage of cooked rice decreased RDS content and increased SDS content in all rice cultivars. However, no increase in RS content during storage was observed. The enthalpy for retrogradation and the intensity ratio 1047/1022 cm–1 during storage were correlated negatively with RDS and positively with SDS (P ≤ 0.01).
Growth and reproductive biology of the foxfish Bodianus frenchii, a very long‐lived and monandric protogynous hermaphroditic labrid
Authors: Cossington S. , Hesp S. A. , Hall N. G. , Potter I. C.
Published: July 2010

Samples of the foxfish Bodianus frenchii, collected over reefs on the lower west and south coasts of Western Australia, contained individuals ranging up to 78 years old. Although B. frenchii is far smaller than many other species within the Labridae, its maximum age is the greatest yet recorded for this highly speciose family and, together with Achoerodus gouldii, provides an example of a temperate hypsigenyine with exceptional longevity. Length and age compositions of females and males and the histological characteristics of gonads of a wide length range of individuals demonstrated that B. frenchii is a protogynous hermaphrodite. Furthermore, as, on both coasts, the length of the smallest male was greater than that at which all females had become mature, B. frenchii is a monandric protogynous hermaphrodite, i.e. all of its males are derived from functional females. Attainment of maturity by females is related more to length than age, whereas the reverse is true for sex change. On the basis of Schnute growth equations and length‐to‐body mass regression equations, the predicted length at age and body mass at length of fish on the south coast were greater than those on the west coast throughout life. Although B. frenchii spawns daily during the main spawning season, which extends from October to February on both coasts, its fecundity at any given length is substantially greater on the south than on the west coast. The more rapid growth of juveniles and earlier attainment of maturity by B. frenchii on the south coast than on the warmer west coast, together with maturation at a similar size on both coasts, run counter to the trends observed in many species and certain ecological theories regarding the relationships between life‐cycle traits and latitude and temperature. The attainment by B. frenchii of a larger body length at age, of greater body mass at length and of greater fecundity at both length and body mass in fish on the south than on the west coast strongly suggests that conditions on the former, cooler coast are more favourable for this labrid, which belongs to a sub‐genus whose other species typically live in cool, deep, temperate waters.
Combined effects of lapatinib and bortezomib in human epidermal receptor 2 (HER2)‐overexpressing breast cancer cells and activity of bortezomib against lapatinib‐resistant breast cancer cells
Authors: Ma Chuandong , Niu Xiuqing , Luo Jianmin , Shao Zhimin , Shen Kunwei
Published: July 2010

Lapatinib and bortezomib are highly active against breast cancer cells. Breast cancer patients who initially respond to lapatinib may eventually manifest acquired resistance to this treatment. Thus, the identification of novel agents that may prevent or delay the development of acquired resistance to lapatinib is critical. In the current study, we show that the combination of lapatinib and bortezomib results in a synergistic growth inhibition in human epidermal receptor 2 (HER2)‐overexpressing breast cancer cells and that the combination enhances apoptosis of SK‐BR‐3 cells. Importantly, we found that the combination of lapatinib plus bortezomib more effectively blocked activation of the HER2 pathway in SK‐BR‐3 cells, compared with monotherapy. In addition, we established a model of acquired resistance to lapatinib by chronically challenging SK‐BR‐3 breast cancer cells with increasing concentrations of lapatinib. Here, we showed that bortezomib notably induced apoptosis of lapatinib‐resistant SK‐BR‐3 pools and further inhibited HER2 signaling in the resistant cells. Taken together, the current data indicate a synergistic interaction between lapatinib and bortezomib in HER2‐overexpressing breast cancer cells and provide the rationale for the clinical evaluation of these two noncross‐resistant targeted therapies. The combination of lapatinib and bortezomib may be a potentially novel approach to prevent or delay the onset of acquired resistance to lapatinib in HER2‐overxpressing/estrogen receptor (ER)‐negative breast cancers. (Cancer Sci 2010); 00: 000–000
ORIGINAL ARTICLE: Potency and recovery characteristics of rocuronium mixed with sodium bicarbonate
Authors: Lee H. J. , Kim K. S. , Yeon J. T. , Suh J. K. , Sung I. H. , Shin I. C.
Published: July 2010

Sodium bicarbonate may be added to rocuronium to decrease pain on injection. However, this mixture may result in the formation of carbon dioxide bubbles. We investigated whether the addition of sodium bicarbonate to rocuronium alters neuromuscular blockade, in 120 patients randomly assigned to receive rocuronium mixed with saline or bicarbonate 8.4%, either in varying doses (for dose‐response measurements; 60 patients) or a fixed dose of 600 μg.kg‐1(for time‐course measurements; 60 patients). Sodium bicarbonate resulted in a left‐shift of the rocuronium dose‐response curve. The effective doses of rocuronium to produce 95% twitch depression were 331.6 (95% CI: 310.4–352.8) and 284.3 (95% CI: 262.0–306.6) μg.kg−1mixed with isotonic saline or sodium bicarbonate, respectively (p < 0.001). The mean (SD) onset times of rocuronium 600 μg.kg‐1were 3.6 (0.6) and 2.7 (0.5) min in the corresponding groups, respectively (p < 0.001). The mean (SD) times to 95% recovery were 35.8 (5.8) and 47.9 (7.1) min, respectively (p < 0.001). We conclude that the mixing of sodium bicarbonate with rocuronium enhances the potency, shortens the onset and prolongs the duration of action.
Standard treatment of Ph+ CML in 2010: how, when and where not to use what BCR/ABL1 kinase inhibitor?
Authors: Valent Peter
Published: July 2010

Eur J Clin Invest 2010; 40 (10): 918–931

Chronic myeloid leukaemia (CML) is a haematopoietic neoplasm characterised by the BCR/ABL1 oncoprotein. In chronic phase CML, the neoplastic clone exhibits multilineage differentiation and maturation capacity. The BCR/ABL1 kinase blocker imatinib shows major antileukaemic effects in most patients and is considered standard frontline therapy. However, not all patients have a long‐lasting response to imatinib. Notably, resistance to imatinib has been recognised as an emerging problem and challenge in CML. Whereas CML stem cells are considered to exhibit intrinsic resistance, acquired resistance may, in addition, develop in subclones over time, resulting in an overt relapse. A key trigger of resistance in subclones are BCR/ABL1 mutations. For such patients, novel multikinase inhibitors such as nilotinib, dasatinib, bosutinib or bafetinib, which block the kinase activity of various BCR/ABL1 mutants, have been developed and reportedly exert antileukaemic effects in drug‐resistant cells. For highly resistant patients, haematopoietic stem cell transplantation is an alternative option. Treatment decisions and the selection of drugs are based on the presence and type of BCR/ABL1 mutation(s), phase of disease, other disease‐related variables and patient‐related factors including age, compliance and co‐morbidity. The current review provides an overview on standards in the diagnosis and therapy in CML, with special reference to novel BCR/ABL1 inhibitors.
p62/SQSTM1 cooperates with Parkin for perinuclear clustering of depolarized mitochondria
Authors: Okatsu Kei , Saisho Keiko , Shimanuki Midori , Nakada Kazuto , Shitara Hiroshi , Sou Yu‐shin , Kimura Mayumi , Sato Shigeto , Hattori Nobutaka , Komatsu Masaaki , Tanaka Keiji , Matsuda Noriyuki
Published: July 2010

PINK1 and Parkin were first identified as the causal genes responsible for familial forms of early‐onset Parkinson’s disease (PD), a prevalent neurodegenerative disorder. PINK1 encodes a mitochondrial serine/threonine protein kinase, whereas Parkin encodes an ubiquitin‐protein ligase. PINK1 and Parkin cooperate to maintain mitochondrial integrity; however, the detailed molecular mechanism of how Parkin‐catalyzed ubiquitylation results in mitochondrial integrity remains an enigma. In this study, we show that Parkin‐catalyzed K63‐linked polyubiquitylation of depolarized mitochondria resulted in ubiquitylated mitochondria being transported along microtubules to cluster in the perinuclear region, which was interfered by pathogenic mutations of Parkin. In addition, p62/SQSTM1 (hereafter referred to as p62) was recruited to depolarized mitochondria after Parkin‐directed ubiquitylation. Intriguingly, deletion of p62 in mouse embryonic fibroblasts resulted in a gross loss of mitochondrial perinuclear clustering but did not hinder mitochondrial degradation. Thus, p62 is required for ubiquitylation‐dependent clustering of damaged mitochondria, which resembles p62‐mediated ‘aggresome’ formation of misfolded/unfolded proteins after ubiquitylation.
Nitrogen deposition and forest nitrogen cycling along an urban–rural transect in southern China
Authors: FANG YUNTING , YOH MUNEOKI , KOBA KEISUKE , ZHU WEIXING , TAKEBAYASHI YU , XIAO YIHUA , LEI CHUNYI , MO JIANGMING , ZHANG WEI , LU XIANKAI
Published: July 2010

There is increasing concern over the impact of atmospheric nitrogen (N) deposition on forest ecosystems in the tropical and subtropical areas. In this study, we quantified atmospheric N deposition and revealed current plant and soil N status in 14 forests along a 150 km urban to rural transect in southern China, with an emphasis on examining whether foliar δ15N can be used as an indicator of N saturation. Bulk deposition ranged from 16.2 to 38.2 kg N ha−1 yr−1, while the throughfall covered a larger range of 11.7–65.1 kg N ha−1 yr−1. Foliar N concentration, NO3− leaching to stream, and soil NO3− concentration were low and NO3− production was negligible in some rural forests, indicating that primary production in these forests may be limited by N supply. But all these N variables were enhanced in suburban and urban forests. Across the study transect, throughfall N input was correlated positively with soil nitrification and NO3− leaching to stream, and negatively with pH values in soil and stream water. Foliar δ15N was between −6.6‰ and 0.7‰, and was negatively correlated with soil NO3− concentration and NO3− leaching to stream across the entire transect, demonstrating that an increased N supply does not necessarily increase forest δ15N values. We proposed several potential mechanism that could contribute to the δ15N pattern, including (1) increased plant uptake of 15N‐depleted soil NO3−, (2) foliage uptake of 15N‐depleted NH4+, (3) increased utilization of soil inorganic N relative to dissolved organic N, and (4) increased fractionation during plant N uptake under higher soil N availability.
Review of pulp sensibility tests. Part I: general information and thermal tests
Authors: Jafarzadeh H. , Abbott P. V.
Published: July 2010

Jafarzadeh H, Abbott PV. Review of pulp sensibility tests. Part Ι: general information and thermal tests. International Endodontic Journal, 43, 738–762, 2010.

A major, and essential, part of the diagnostic process for pulp disease is the use of pulp sensibility tests. When diagnosing pulp pain, these tests can be used to reproduce the symptoms reported by the patient to diagnose the diseased tooth as well as the disease state. However, a major shortcoming with these tests is that they only indirectly provide an indication of the state of the pulp by measuring a neural response rather than the vascular supply, so both false positive and false negative results can occur. The relevant literature on pulp sensibility tests in the context of endodontics up to January 2009 was reviewed using PubMed and MEDLINE database searches. This search identified papers published between November 1964 and January 2009 in all languages. Thermal tests have been used as an integral part of dental examinations. Two types of thermal tests are available, one uses a cold stimulus and the other uses a hot stimulus, and each has various methods of delivery. If these tests are used properly, injury to the pulp is highly unlikely. A review of the literature regarding the rationale, indications, limitations, and interpretation of thermal tests, the value of these diagnostic tests, as well as a discussion of the important points about each of these tests is presented.
The effect of root canal taper on the irrigant flow: evaluation using an unsteady Computational Fluid Dynamics model
Authors: Boutsioukis C. , Gogos C. , Verhaagen B. , Versluis M. , Kastrinakis E. , Van Der Sluis L. W. M.
Published: July 2010

Boutsioukis C, Gogos C, Verhaagen B, Versluis M, Kastrinakis E, van der Sluis LWM. The effect of root canal taper on the irrigant flow: evaluation using an unsteady Computational Fluid Dynamics model. International Endodontic Journal, 43, 909–916, 2010.

Aim  To evaluate the effect of root canal taper on irrigant flow inside a prepared root canal during final irrigation with a syringe and two types of needles, using a Computational Fluid Dynamics (CFD) model.

Methodology  A validated CFD model was used to simulate irrigant flow from either a side‐vented or a flat 30G needle positioned inside size 30, .02 taper, 30, .04, 30, .06, ProTaper F3 or size 60, .02 taper root canals, at 3 mm short of working length (WL). Velocity, pressure and shear stress in the root canal were evaluated.

Results  The side‐vented needle could not achieve irrigant replacement to the WL in any of the cases. Significant irrigant replacement was evident further than 2 mm apically to the tip of the flat needle in the size 30, .06 taper, F3 and size 60, .02 taper canal. A wider distribution of wall shear stress was noted as the canal taper increased but the maximum shear stress decreased. The flat needle led to higher mean pressure at the apical foramen. Both needles showed a similar gradual decrease in apical pressure as the taper increased, but the least pressure was calculated in the size 60, .02 taper canal.

Conclusions  An increase in root canal taper improved irrigant replacement and wall shear stress whilst reducing the risk for irrigant extrusion. Irrigant flow in a minimally tapered root canal with a large apical preparation size also improved irrigant replacement and wall shear stress and reduced the risk for irrigant extrusion, compared to the tapered root canals with a smaller apical preparation size.
Nursing education in Denmark, Finland, Norway and Sweden – from Bachelor’s Degree to PhD
Authors: Råholm Maj‐Britt , Hedegaard Birte Larsen , Löfmark Anna , Slettebø Åshild
Published: July 2010

råholm m‐b., hedegaard b.l., löfmark a. & slettebøå. (2010) Nursing education in Denmark, Finland, Norway and Sweden – from Bachelor’s Degree to PhD. Journal of Advanced Nursing 66(9), 2126–2137.

Aim.  This paper is a discussion of the similarities and differences in baccalaureate nursing education programme structures, content and pathways to postbaccalaureate education in the Scandinavian countries.

Background.  For the last three decades nursing education internationally, as well as in the Scandinavian countries, has experienced ongoing reforms. The driving forces behind these reforms have been efforts for professional development within nursing and to harmonize higher education in several European countries.

Data sources.  The data were collected by a critical review of the guiding principles, national directives and educational structures and content of Bachelor’s degree programmes from 1990 to 2008 and of further educational levels in the four Scandinavian countries.

Discussion.  There are similarities as well as substantial differences in the educational structures, contents and lengths in the different nursing programmes. Nursing education is organized in the three cycles described in the Bologna Process, but there are differences regarding names and terms for degrees and allocation of European Credit Transfer System credits.

Implications for nursing.  Policymakers need to consider more carefully the directives in the Bologna Declaration when planning and implementing nursing programmes at Bachelor’s and postgraduate levels. Knowledge of the content and structure of nursing education in these countries may enhance development and cooperation between institutions.

Conclusion.  A challenge for the ministries of education in the Scandinavian countries is to compare and coordinate nursing educational programmes in order to enable nursing students, educators, researchers and nurses to study and work in Scandinavia, Europe or even globally.
Empowerment of nursing students in clinical practice: spheres of influence
Authors: Bradbury‐Jones Caroline , Irvine Fiona , Sambrook Sally
Published: July 2010

bradbury‐jones c., irvine f. & sambrook s. (2010) Empowerment of nursing students in clinical practice: spheres of influence. Journal of Advanced Nursing 66(9), 2061–2070.

Aim.  This paper is a report of a study exploring the empowerment of nursing students in clinical practice.

Background.  There is a great deal of literature regarding empowerment in nursing but most focuses on the empowerment of patients and registered nurses. There is very little regarding the empowerment of nursing students. Of the limited available studies, most explore empowerment in an academic, rather than a clinical context.

Methods.  This longitudinal study was underpinned by hermeneutic phenomenology. Thirteen first‐year nursing students were recruited using a purposive sampling strategy. Annual, in‐depth interviews were conducted with the students on their trajectory from the first to third year of the undergraduate programme. Data were collected between 2007 and 2009.

Findings.  By the end of the study, most students felt more empowered than they had at the beginning. They attributed this to increased knowledge and confidence. Empowerment of nursing students in clinical practice can be represented in the form of ‘spheres of influence’. Intrinsic, essential structures of having knowledge and confidence are at the core. External spheres influence the extent to which nursing students are likely to experience increased knowledge and confidence, and thus empowerment. However, nursing students use a number of strategies to promote their own empowerment in clinical practice.

Conclusion.  Efforts to promote the empowerment of nursing students in clinical practice need to be multi‐layered and targeted at each of the spheres of influence.
Understanding whistleblowing: qualitative insights from nurse whistleblowers
Authors: Jackson Debra , Peters Kath , Andrew Sharon , Edenborough Michel , Halcomb Elizabeth , Luck Lauretta , Salamonson Yenna , Wilkes Lesley
Published: July 2010

jackson d., peters k., andrew s., edenborough m., halcomb e., luck l., salamonson y. & wilkes l. (2010) Understanding whistleblowing: qualitative insights from nurse whistleblowers. Journal of Advanced Nursing 66(10), 2194–2201.

Aim.  This paper is a report of a study conducted to explore the reasons behind the decision to blow the whistle and provide insights into nurses’ experiences of being whistleblowers.

Background.  Whistleblowing is a stigmatized and hidden activity that carries considerable ramifications to all concerned. In the health sector, when episodes of poor practice or service provision are identified, it is frequently nurses who are the whistleblowers. Despite this, there is remarkably limited literature that explores nurses’ experiences of whistleblowing.

Methods.  Qualitative narrative inquiry design. Data were collected in 2008 from 11 nurse whistleblowers using in‐depth semi‐structured interviews.

Findings.  Participants were drawn from a range of general and specialty clinical areas and experienced whistleblowing as highly stressful. The findings were clustered into three main themes, namely: (i) Reasons for whistleblowing: I just couldn’t advocate, (ii) Feeling silenced: Nobody speaks out, and (iii) Climate of fear: You are just not safe.

Conclusion.  The whistleblowing nurses believed they were acting in accordance with a duty of care. There is a need for greater clarity about the role nurses have as patient advocates. Furthermore, there is need to develop clear guidelines that create opportunities for nurses to voice concerns and to ensure that healthcare systems respond in a timely and appropriate manner, and a need to foster a safe environment in which to raise issues of concern.
Effectiveness of exercise programmes on shoulder mobility and lymphoedema after axillary lymph node dissection for breast cancer: systematic review
Authors: Chan Dorothy N.S. , Lui Liza Y.Y. , So Winnie K.W.
Published: July 2010

chan d.n.s., lui l.y.y. & so w.k.w. (2010) Effectiveness of exercise programmes on shoulder mobility and lymphoedema after axillary lymph node dissection for breast cancer: systematic review. Journal of Advanced Nursing 66(9), 1902–1914.

Aim.  This article is a report of a review of the effectiveness of exercise programmes on shoulder mobility and lymphoedema in postoperative patients with breast cancer having axillary lymph node dissection, as revealed by randomized controlled trials.

Background.  Breast cancer is the most common malignancy in women. After surgery, the most common postoperative complications are reduced range of motion in the shoulder, muscle weakness in the upper extremities, lymphoedema, pain and numbness. To reduce these impairments, shoulder exercises are usually prescribed. However, conflicting results regarding the effect and timing of such exercises have been reported.

Data sources.  Studies were retrieved from a systematic search of published works over the period 2000–2009 indexed in the Cumulative Index to Nursing and Allied Health Literature, Ovid Medline, the British Nursing Index, Proquest, Science Direct, Pubmed, Scopus and the Cochrane Library, using the combined search terms ‘breast cancer’, ‘breast cancer surgery’, ‘exercise’, ‘lymphoedema’, ‘shoulder mobility’ and ‘randomized controlled trials’.

Methods.  A quantitative review of effectiveness was carried out. Studies were critically appraised by three independent reviewers, and categorized according to levels of evidence defined by the Joanna Briggs Institute.

Results.  Six studies were included in the review. Early rather than delayed onset of training did not affect the incidence of postoperative lymphoedema, but early introduction of exercises was valuable in avoiding deterioration in range of shoulder motion.

Conclusion.  Further studies are required to investigate the optimal time for starting arm exercises after this surgery. Nurses have an important role in educating and encouraging patients to practise these exercises to speed up recovery.
Nurses’ work environments, care rationing, job outcomes, and quality of care on neonatal units
Authors: Rochefort Christian M. , Clarke Sean P.
Published: July 2010

rochefort c.m. & clarke s.p. (2010) Nurses’ work environments, care rationing, job outcomes, and quality of care on neonatal units. Journal of Advanced Nursing 66(10), 2213–2224.

Aim.  This paper is a report of a study of the relationship between work environment characteristics and neonatal intensive care unit nurses’ perceptions of care rationing, job outcomes, and quality of care.

Background.  International evidence suggests that attention to work environments might improve nurse recruitment and retention, and the quality of care. However, comparatively little attention has been given to neonatal care, a specialty where patient and nurse outcomes are potentially quite sensitive to problems with staffing and work environments.

Methods.  Over a 6‐month period in 2007–2008, a questionnaire containing measures of work environment characteristics, nursing care rationing, job satisfaction, burnout and quality of care was distributed to 553 nurses in all neonatal intensive care units in the province of Quebec (Canada).

Results.  A total of 339 nurses (61·3%) completed questionnaires. Overall, 18·6% were dissatisfied with their job, 35·7% showed high emotional exhaustion, and 19·2% rated the quality of care on their unit as fair or poor. Care activities most frequently rationed because of insufficient time were discharge planning, parental support and teaching, and comfort care. In multivariate analyses, higher work environment ratings were related to lower likelihood of reporting rationing and burnout, and better ratings of quality of care and job satisfaction.

Conclusion.  Additional research on the determinants of nurse outcomes, the quality of patient care, and the impact of rationing of nursing care on patient outcomes in neonatal intensive care units is required. The Neonatal Extent of Work Rationing Instrument appears to be a useful tool for monitoring the extent of rationing of nursing care in neonatal units.
Facial muscle activation during sleep and its relation to the rapid eye movements of REM sleep
Authors: RIVERA‐GARCÍA ANA PAULA , RAMÍREZ‐SALADO IGNACIO , CORSI‐CABRERA MARÍA , CALVO JOSÉ MARÍA
Published: July 2010

Facial muscle contractions (FMC) are a commonly observed feature during sleep stages in human subjects. Previous studies have associated FMC to emotional expression during waking. Phasic features of rapid eye movement (REM) sleep, such as REMs have also been linked to an increase in limbic structure activity with a subsequent relation to emotional dream content. We hypothesized that FMC would be more frequent during REM sleep, and that FMC would correlate with the characteristic REMs of this sleep stage. The present study was designed to evaluate the density per minute of the phasic and sustained FMC of five facial muscles (frontalis, corrugator, orbicularis oculi, zygomatic major left and right) during all sleep stages, and to explore their relation with REMs density in six healthy participants during an 8 h sleep recording. Results showed a significant increase in FMC of all recorded muscles during REM sleep, both in frequency and duration. Additionally, as expected, during REM sleep there was a positive correlation among the facial muscles and between these and REMs. Nevertheless, although associated in number, both features (FMC and REMs) were never simultaneous. Our results suggest that limbic activation during REM sleep may be responsible for the enhancement of facial muscle activity, which may be consistent with the theoretical perspective of a higher emotional activity during REM sleep.
Self‐reported sleep duration and falls in older adults
Authors: MESAS ARTHUR EUMANN , LÓPEZ‐GARCÍA ESTHER , RODRÍGUEZ‐ARTALEJO FERNANDO
Published: July 2010

Whether the association between sleep duration and accidental falls is independent of sleep quality is uncertain. It is also unclear if this association varies with age and sex among older adults. Data were collected through telephone interviews of 1542 community‐dwelling individuals aged ≥68 years in Spain. Analyses were performed with logistic regression and adjusted for the main confounders, including lifestyle, health status, comorbidity and sleep quality, as measured by nighttime and daytime sleep complaints. Analyses were also stratified by age and sex. In total, 449 (29.1%) participants fell in the previous year; of these, 57.7% had one fall and 42.3% had recurrent (≥2) falls. As compared with those who usually slept 7–8 h, those sleeping ≥11 h were more likely to suffer recurrent falls [odds ratios (OR) 2.75; 95% confidence intervals (CI) 1.32–5.62]. In the stratified analysis, there was no association between sleep duration and falls in those aged ≤75 years and in men. In contrast, among those aged >75 years, the percentage of individuals with ≥1 falls was higher in those sleeping ≤5 h (OR 2.15; 95% CI 1.20–3.87) and ≥11 h (OR 2.34; 95% CI 1.17–4.68) than in those sleeping 7–8 h; also, women who slept ≥11 h were more likely to fall ≥1 times (OR 3.89; 95% CI 1.74–8.69). In conclusion, long sleep duration was associated with higher frequency of falls in older adults, even after adjustment for a wide range of sleep quality indicators. The association is clearer in women and the oldest adults. Assessment of sleep duration can help identify older adults who might benefit from interventions aimed at fall prevention.
Detection of human papillomavirus DNA in feline premalignant and invasive squamous cell carcinoma
Authors: O’Neill Sarah H. , Newkirk Kimberly M. , Anis Eman A. , Brahmbhatt Rupal , Frank Linda A. , Kania Stephen A.
Published: July 2010

Squamous cell carcinoma (SCC) is the most common malignant cutaneous and oral neoplasm of cats. Papillomavirus (PV) DNA has been identified in a proportion of feline Bowenoid in situ carcinomas (BISCs), cutaneous SCCs and a single oral SCC, but its exact role in the pathogenesis remains unknown. In humans, it has been suggested that ultraviolet (UV) light and human PV (HPV) may act as cofactors in cutaneous SCC carcinogenesis. Little is known about the influence of UV light on PV prevalence in feline cutaneous lesions, including actinic keratosis (AK). Additionally, PV prevalence in noncutaneous feline lesions, including oral SCC, is largely not known. This study aimed to determine the presence of PV in 84 cats with premalignant and invasive SCC from cutaneous and noncutaneous sites using polymerase chain reaction and to investigate an association with UV light. Papillomaviral DNA was amplified from two of 12 cases of AK, seven of 22 BISCs, nine of 39 cutaneous SCCs and two of 35 non‐cutaneous SCCs. Of the PV DNA sequenced, 50% was most similar to HPV of the genus Betapapillomavirus, while the other 50% was most similar to Felis domesticus PV type 2. Exposure to UV was not associated with an increase in PV for cutaneous SCC. The results of this study suggest that in the cat, HPV DNA may be detectible within a higher percentage of squamous lesions than previously demonstrated, UV exposure may not be a confounder for PV presence, and noncutaneous lesions may have a low prevalence of PV.