bluuebunny/crossref_metadata_2025 huggingface dataset:
Elastic properties of porous silicon studied by acoustic transmission spectroscopy
Authors: Aliev G. N. , Goller B. , Snow P. A.
Published: September 2011

The porosity dependence of the elastic properties of porous silicon in different crystallographic directions is studied. The velocity of longitudinal acoustic waves in porous silicon layers electrochemically etched in (100), (110), and (111) oriented wafers has been measured by acoustic spectroscopy in the gigahertz frequency range. This non-destructive method was used for porous silicon layers with porosity of 25-85% obtaining velocities in the range of about 1 to 7 km s-1. The implication of constant Poisson’s ratio of porous silicon is examined. The effect of velocity dispersion due to multiple scattering is considered. The c11 stiffness constant can be obtained from the velocity measurement in the [100] direction of a cubic crystal. We show that, using the results for velocity in [110] or [111] directions and Keating’s relation, the stiffness constants c12 and c44 can be obtained. The velocity dependence on porosity was fitted as v=v0(1-φ)κ, where v0 is the velocity in bulk silicon, φ is porosity, and κ is a fitting parameter. It is shown that with other conditions being equal: (i) the porosity dependence of the acoustic velocity is related to the doping level of the wafer from which the porous silicon was etched (κ depends on wafer resistivity); (ii) acoustic velocities in different crystallographic directions have the same dependence on porosity (κ is independent of wafer orientation). This requires that all three stiffness constants c11, c12 and c44 have the same dependence on porosity: cij=cij0(1-φ)m; and (iii) the morphology of porous layers depends on the HF concentration in the etchant (κ is used as an indicator for the disorder of the porous structure).
Adaptive stochastic methods for sampling driven molecular systems
Authors: Jones Andrew , Leimkuhler Ben
Published: September 2011

Thermostatting methods are discussed in the context of canonical sampling in the presence of driving stochastic forces. Generalisations of the Nosé-Hoover method and Langevin dynamics are introduced which are able to dissipate excess heat introduced by steady Brownian perturbation (without a priori knowledge of its strength) while preserving ergodicity. Implementation and parameter selection are considered. It is demonstrated using numerical experiments that the methods derived can adaptively control the target canonical ensemble in the presence of nonlinear driving perturbations.
Patterned polarized fluorescence from a thin film
Authors: Myhre G. , Sayyad A , Mataka S. , Pau S.
Published: September 2011

Patterned polarized fluorescence from a thin film comprised of fluorescent dichroic dye dispersed in liquid crystalline polymer is demonstrated with features as small as 11 μm. Cooperative alignment of these fluorescent dichroic molecules in a liquid crystal polymer leads to films exhibiting polarized green, red, and yellow emission. The dichroic fluorescence emission ratios for these films are 10 to 16 depending on the type of the dye. This simple strategy could be utilized for generating large area linearly polarized light sources or electroluminescent displays.
Induced static magnetic field by a cellular phone
Authors: Einat M. , Yahalom A.
Published: September 2011

Recent claims regarding the safety of cellular phones suggest that weak static magnetic fields are induced around the phone, and this field and its gradients may pose a health risk to the user. An experiment was conducted to measure the induced static magnetic field around a cellular phone. 65 μT variations and 18 μT/cm gradients were measured in the magnetic field at 6 cm from the phone. An analytical model is derived to explain the results. The influence that the measured magnetic fields may have on the user is beyond the scope of this research.
Modelling radiation spectrum of a discharge with two liquid non-metallic (tap-water) electrodes in air at atmospheric pressure
Authors: Andre P , Barinov Yu A , Faure G , Shkol'nik S M
Published: September 2011

The emission spectra of a column of a direct-current discharge in open air which is performed between two tap-water electrodes (two tap-water flows) are studied in the 240–450 nm spectral range. A comparison of the values of spectral emissivities is made between experimental spectra and the calculated spectra. The emission spectrum calculation is made for four molecules, N2, O2, NO and OH that are present in air plasma. The first part of this paper focuses on building the spectra calculation; the required data are detailed. In the second part, rotational, vibrational and excitational temperatures are determined with the Boltzmann distribution assumed on the quantum states. For that purpose, a comparison of the modelled spectra and the experimental spectra is made in the different parts of the discharge column.
Overview of results from the Large Helical Device
Authors: Yamada H.
Published: September 2011

The physical understanding of net-current-free helical plasmas has progressed in the Large Helical Device (LHD) since the last Fusion Energy Conference in Geneva, 2008. The experimental results from LHD have promoted detailed physical documentation of features specific to net-current-free 3D helical plasmas as well as complementary to the tokamak approach. The primary heating source is neutral beam injection (NBI) with a heating power of 23 MW, and electron cyclotron heating with 3.7 MW plays an important role in local heating and power modulation in transport studies. The maximum central density has reached 1.2 × 1021 m−3 due to the formation of an internal diffusion barrier (IDB) at a magnetic field of 2.5 T. The IDB is maintained for 3 s by refuelling with repetitive pellet injection. In a different operational regime with moderate density less than 2 × 1019 m−3, a plasma with a central ion temperature reaching 5.6 keV exhibits the formation of an internal transport barrier (ITB). The ion thermal diffusivity decreases to the level predicted by neoclassical transport. In addition to the rotation driven by the momentum input due to tangential NBI, the existence of intrinsic torque to drive toroidal rotation is identified in the plasma with an ITB. This ITB is accompanied by an impurity hole which generates an impurity-free core. The impurity hole is due to a large outward convection of impurities in spite of the negative radial electric field. The magnitude of the impurity hole is enhanced in the magnetic configuration with a large helical ripple and for heavier atoms. Another mechanism for suppressing impurity contamination is identified at the plasma edge with a stochastic magnetic field. A helical system shares common physics issues with tokamaks such as 3D equilibria, transport in a stochastic magnetic field, plasma response to a resonant magnetic perturbation, divertor physics and the role of radial electric field and meso-scale structure.
Robustness portraits of diverse biological networks conserved despite order-of-magnitude parameter uncertainty
Authors: Soltis Anthony R. , Saucerman Jeffrey J.
Published: September 2011

Motivation: Biological networks are robust to a wide variety of internal and external perturbations, yet fragile or sensitive to a small minority of perturbations. Due to this rare sensitivity of networks to certain perturbations, it is unclear how precisely biochemical parameters must be experimentally measured in order to accurately predict network function.

Results: Here, we examined a model of cardiac β-adrenergic signaling and found that its robustness portrait, a global measure of steady-state network function, was well conserved even when all parameters were rounded to their nearest 1–2 orders of magnitude. In contrast, β-adrenergic network kinetics were more sensitive to parameter precision. This analysis was then extended to 10 additional networks, including Escherichia coli chemotaxis, stem cell differentiation and cytokine signaling, of which nine exhibited conserved robustness portraits despite the order-of-magnitude approximation of their biochemical parameters. Thus, both fragile and robust aspects of diverse biological networks are largely shaped by network topology and can be predicted despite order-of-magnitude uncertainty in biochemical parameters. These findings suggest an iterative strategy where order-of-magnitude models are used to prioritize experiments toward the fragile network elements that require precise measurements, efficiently driving model revision.

Contact:  jsaucerman@virginia.edu

Supplementary information:  Supplementary data are available at Bioinformatics online.
Biologically inspired crack delocalization in a high strain-rate environment
Authors: Knipprath Christian , Bond Ian P. , Trask Richard S.
Published: September 2011

Biological materials possess unique and desirable energy-absorbing mechanisms and structural characteristics worthy of consideration by engineers. For example, high levels of energy dissipation at low strain rates via triggering of crack delocalization combined with interfacial hardening by platelet interlocking are observed in brittle materials such as nacre, the iridescent material in seashells. Such behaviours find no analogy in current engineering materials. The potential to mimic such toughening mechanisms on different length scales now exists, but the question concerning their suitability under dynamic loading conditions and whether these mechanisms retain their energy-absorbing potential is unclear. This paper investigates the kinematic behaviour of an ‘engineered’ nacre-like structure within a high strain-rate environment. A finite-element (FE) model was developed which incorporates the pertinent biological design features. A parametric study was carried out focusing on (i) the use of an overlapping discontinuous tile arrangement for crack delocalization and (ii) application of tile waviness (interfacial hardening) for improved post-damage behaviour. With respect to the material properties, the model allows the permutation and combination of a variety of different material datasets. The advantage of such a discontinuous material shows notable improvements in sustaining high strain-rate deformation relative to an equivalent continuous morphology. In the case of the continuous material, the shockwaves propagating through the material lead to localized failure while complex shockwave patterns are observed in the discontinuous flat tile arrangement, arising from platelet interlocking. The influence of the matrix properties on impact performance is investigated by varying the dominant material parameters. The results indicate a deceleration of the impactor velocity, thus delaying back face nodal displacement. A final series of FE models considered the identification of an optimized configuration as a function of tile waviness and matrix properties. In the combined model, the optimized configuration was capable of stopping the ballistic threat, thus indicating the potential for bioinspired toughened synthetic systems to defeat high strain-rate threats.
Geometrical constraints in the scaling relationships between genome size, cell size and cell cycle length in herbaceous plants
Authors: Šímová Irena , Herben Tomáš
Published: September 2011

Plant nuclear genome size (GS) varies over three orders of magnitude and is correlated with cell size and growth rate. We explore whether these relationships can be owing to geometrical scaling constraints. These would produce an isometric GS–cell volume relationship, with the GS–cell diameter relationship with the exponent of 1/3. In the GS–cell division relationship, duration of processes limited by membrane transport would scale at the 1/3 exponent, whereas those limited by metabolism would show no relationship. We tested these predictions by estimating scaling exponents from 11 published datasets on differentiated and meristematic cells in diploid herbaceous plants. We found scaling of GS–cell size to almost perfectly match the prediction. The scaling exponent of the relationship between GS and cell cycle duration did not match the prediction. However, this relationship consists of two components: (i) S phase duration, which depends on GS, and has the predicted 1/3 exponent, and (ii) a GS-independent threshold reflecting the duration of the G1 and G2 phases. The matches we found for the relationships between GS and both cell size and S phase duration are signatures of geometrical scaling. We propose that a similar approach can be used to examine GS effects at tissue and whole plant levels.
Genomic characterization of a novel human adenovirus type 31 recombinant in the hexon gene
Authors: Matsushima Yuki , Shimizu Hideaki , Phan Tung Gia , Ushijima Hiroshi
Published: September 2011

A novel human recombinant adenovirus of species A (HAdV-A31 MZ) was isolated from a patient with acute gastroenteritis in Japan. The complete genome of HAdV-A31 strain MZ contains 33 776 bp. Analysis of the hexon gene of HAdV-A31 MZ indicated that its hexon sequence is the result of a genetic recombination between those of HAdV-A31 and a close relative to HAdV-A12. The recombination sites were found around the border of hypervariable loops 1 and 2 in the hexon gene, which are the most important determinants for virus neutralization. Loops 1 and 2 of this virus were genetically related to HAdV-A12, whereas all other parts of the genome were highly similar to HAdV-A31. In order to understand the evolution of adenoviruses correctly and to avoid misidentification of HAdV types, we recommend characterizing not only the hexon gene, but also the penton base and fiber genes.
The N-terminal 12 amino acids of tomato aspermy virus 2b protein function in infection and recombination
Authors: Shi Bu-Jun , Palukaitis Peter
Published: September 2011

The roles for various regions of the 2b protein in infection, hypervirulence and recombination were examined by introducing stop codons in a chimeric virus containing RNA 1 from the cucumber mosaic virus (CMV strain Q), RNA 3 from the tomato aspermy virus (TAV) and RNA 2 of CMV with a 2b gene from TAV. Chimeric virus expressing the intact 2b protein induced severe symptoms in inoculated Nicotiana clevelandii and Nicotiana glutinosa and facilitated CMV–TAV recombination, while chimeric viruses not expressing 2b protein did not infect plants systemically. Chimeric viruses expressing either the N-terminal 43 or 12 aa of the 2b protein infected both plant species systemically and facilitated CMV–TAV recombination, but induced mild symptoms and no symptoms in the infected plants, respectively. These data suggest that oligopeptides can have important functions in the biology of viruses and prompt a re-examination of existing small ORFs in sequenced virus genomes.
The effect of methadone on emotional reactivity
Authors: Savvas Steven M. , Somogyi Andrew A. , White Jason M.
Published: September 2011

Aims  Opioids have been implicated in emotion regulation. Opioid users report decreased negative emotional response, but there has been no formal study on the effect of opioid administration on emotional reactivity. The aim of this study was to investigate the effect of methadone on emotional reactivity in methadone‐maintained patients.

Design  Velten's mood induction procedures were used to induce elative and depressive emotional reactions in the subjects. Each group was administered both induction procedures at 0 hour and 3 hours (corresponding with trough and peak plasma methadone concentrations in methadone subjects).

Setting  A drug treatment clinic with an out‐patient methadone maintenance treatment programme.

Participants  Twenty‐one subjects currently on methadone maintenance treatment and 21 controls with no history of opioid dependence.

Measurements  Emotional reactivity was measured using mood visual analogue scales.

Findings  At 0 hour, methadone and control subjects showed similar elation (methadone 13.2 ± 3.1 mean ± standard error of the mean [SEM], control 14.4 ± 3.7) and depression reactivity (methadone 23.6 ± 5.0, control 25.1 ± 5.0). However, at 3 hours repeated measures showed that methadone subjects had significantly decreased depression reactivity (methadone 18.5 ± 4.6, control 36.7 ± 5.7; P = 0.021) and elation reactivity (methadone 4.4 ± 1.9, control 19.0 ± 2.4) compared to controls.

Conclusions  Opioid addicts on methadone maintenance appear to be less reactive to mood induction at times of peak plasma methadone concentration than non‐addict controls; this suggests that methadone blunts both elative and depressive emotional reactivity.
Engagement with opioid maintenance treatment and reductions in crime: a longitudinal national cohort study
Authors: Bukten Anne , Skurtveit Svetlana , Gossop Michael , Waal Helge , Stangeland Per , Havnes Ingrid , Clausen Thomas
Published: September 2011

Aims  This study investigates changes in criminal involvement among patients in opioid maintenance treatment (OMT) over a 7‐year period prior to, during and after treatment, particularly in relation to differences in treatment engagement.

Design, setting and participants  Treatment data on all patients who started OMT in Norway between 1997 and 2003 (n = 3221) were cross‐linked with national criminal records. The period of observation was divided into four phases; pre‐treatment, in‐treatment, between treatments and post‐treatment.

Findings  During OMT, rates of criminal convictions for the cohort were reduced to fewer than half of waiting‐list levels [incidence rate (IR) 0.63 versus 1.57]. Patients in continuous treatment had the fewest convictions (IR 0.47) during treatment. The highest rates were found among patients out of treatment after several treatment episodes (IR 1.52). All groups had significantly fewer criminal convictions during treatment compared to before treatment. Staying in OMT for 2 years or more was associated with significantly reduced rates of convictions during treatment. Younger age and pre‐treatment criminal convictions were associated with significantly (P < 0.001) more convictions during treatment. Those who left treatment, permanently or temporarily, relapsed into high levels of convictions outside treatment.

Conclusions  Criminal activity appears to be reduced in Norway during opiate maintenance treatment. Younger age and prior history of criminal activity are important risk factors for continued criminal activity during treatment.
The linkage between fault throw and footwall scarp erosion patterns: an example from the Bremstein Fault Complex, offshore Mid‐Norway
Authors: Elliott Gavin M. , Wilson Paul , Jackson Christopher A.‐L. , Gawthorpe Robert L. , Michelsen Lisa , Sharp Ian R.
Published: September 2011

Studies of normal fault systems in modern extensional regimes (e.g. Basin and Range), and in exhumed, ancient rift basins (e.g. Gulf of Suez Rift) have shown a link between the evolution of fault‐related footwall topography and associated erosional drainage systems. In this study, we use 3D seismic reflection data to image the footwall crest of a gravity‐driven fault system developed during late Middle Jurassic to Early Cretaceous rifting on the Halten Terrace, offshore Mid‐Norway. This 22‐km‐long fault system lacks significant footwall uplift, with hangingwall subsidence accommodating throw accumulation on the fault system. Significant erosion has occurred along the length of the footwall crest and is defined by 96 catchments characterized by erosional channels. These erosional channels consist of small, linear systems up to 750 m long located along the front of the fault footwall. Larger, dendritic channel systems extend further back (up to 3 km normal to fault strike) into the footwall. These channels are up to 7 km long, up to 50 m deep and up to 1 km wide. Fault throw varies along strike, with greatest throw in the centre of the fault decreasing towards the fault tips; localized throw minima are interpreted to represent segment linkage points, which were breached as the fault grew. Comparison of the catchment location to the throw distribution shows that the largest catchments are in the centre of the fault and decrease in size to the fault tips. There is no link between the location of the breached segment linkage points and the location and size of the footwall catchments, suggesting that the first‐order control on footwall erosion patterns is the overall fault‐throw distribution.
Genomic analysis of Non‐Splenic Marginal Zone Lymphomas (MZL) indicates similarities between nodal and extranodal MZL and supports their derivation from Memory B‐cells
Authors: Novak Urban , Basso Katia , Pasqualucci Laura , Dalla‐Favera Riccardo , Bhagat Govind
Published: September 2011

Three distinct categories of marginal zone lymphomas (MZLs) are currently recognized, principally based on their site of occurrence. They are thought to represent unique entities, but the relationship of one subtype with another is poorly understood. We investigated 17 non‐splenic MZLs (seven nodal, 10 extranodal) by gene expression profiling to distinguish between subtypes and determine their cell of origin. Our findings suggest biological inter‐relatedness of these entities despite occurrence at different locations and associations with possibly different aetiologies. Furthermore, the expression profiles of non‐splenic MZL were similar to memory B cells.
Selective down‐regulation of Th2 cell‐mediated airway inflammation in mice by pharmacological intervention of CCR4
Authors: Kaminuma O. , Ohtomo T. , Mori A. , Nagakubo D. , Hieshima K. , Ohmachi Y. , Noda Y. , Katayama K. , Suzuki K. , Motoi Y. , Kitamura N. , Saeki M. , Nishimura T. , Yoshie O. , Hiroi T.
Published: September 2011

Background

The chemokine receptor CCR4 has been implicated in Th2 cell‐mediated immune responses. However, other T cell subsets are also known to participate in allergic inflammation.

Objective

The role of CCR4 in Th1, Th2, and Th17 cell‐mediated allergic airway inflammation was investigated.

Method

We generated an allergic airway inflammation model by adoptive transfer of in vitro‐polarized ovalbumin (OVA)‐specific Th1, Th2, and Th17 cells. The effect of a low‐molecular weight CCR4 antagonist, Compound 22, on this model was examined.

Results

Upon in vitro polarization of DO11.10 naïve T cells, Th1‐ and Th2‐polarized cells dominantly expressed CXCR3 and CCR4, respectively, while Th17‐polarized cells expressed CCR6 and CCR4. Intranasal OVA‐challenge of mice transferred with each T cell subset induced accumulation of T cells in the lungs. Eosinophils were also massively accumulated in Th2‐transferred mice, whereas neutrophils were preferentially recruited in Th1‐ and Th17‐transferred mice. Compound 22, as well as anti‐CCL17 or anti‐CCL22 antibody selectively suppressed accumulation of Th2 cells and eosinophils in the lungs of Th2‐transferred and OVA‐challenged mice. Compound 22 also inhibited bronchial hyperresponsiveness but had little effect on goblet cell hyperplasia in Th2‐transferred and OVA‐challenged mice.

Conclusions and Clinical Relevance

There were notable differences in allergic lung inflammation mediated by different T cell subsets. CCR4 blockage was selectively effective for suppression of Th2‐mediated allergic inflammation by blocking infiltration of Th2 cells.
Analysis of the differentially expressed genes in Microsporum canis in inducing smooth skin and scalp tissue conditions
Authors: Zhang F. R. , Zhang Y. , Zhang Z. Y. , Yang G. L. , Jing L. J. , Bai Y. G.
Published: September 2011

Microsporum canis is a common zoophilic dermatophyte, which causes a range of infections. To explore the pathogenic mechanism of tinea capitis, we used the suppression subtractive hybridization (SSH) technique to investigate the differences in gene expression between different cultures of Microsporum canis incubated on three different types of mineral media containing child glabrous skin, child scalp tissue and adult scalp tissue. Using dot-blot hybridization and real-time PCR technique, we successfully screened and identified a pair of genes that had expression levels 44.6 and 117 times higher in culture 1 (M. canis cultured in mineral medium with child scalp tissue) than in culture 2 (M. canis cultured in mineral medium with glabrous skin tissue), and another pair of genes with expression levels 78.2 and 9.8 times higher in culture 1 than in culture 3 (M. canis cultured in mineral medium with adult scalp tissue). These four genes were found to have 41%, 53%, 40% and 94% homology to those encoding a hypothetical protein [family of serine hydrolases 1; (FSH1)], PQ loop repeat protein (PQ-LRP), a predicted protein [porphyrin galactose 4; (P-GAL4)] and NADH dehydrogenase subunit (NADH)1, respectively. The upregulation of the FSH1, PQ-LRP, P-GAL4 and NADH1 genes in cultures of child scalp tissue indicates that they are essential in the pathogenesis of tinea capitis caused by M. canis.
Granulysin-producing cytotoxic T cells in the mucocutaneous lesions of Behçet disease: a distinct inflammatory response from erythema nodosum
Authors: Yamasaki O. , Morizane S. , Aochi S. , Ogawa K. , Oono T. , Iwatsuki K.
Published: September 2011

Background. Cytotoxic T lymphocytes (CTLs) have been recognized as an important effector cell in Behçet disease (BD). Granulysin is a cytolytic granule protein expressed by CTLs and natural killer cells.

Aim. To evaluate the involvement of granulysin-producing T cells in the pathogenesis of BD.

Methods. Using immunohistochemistry, lymphocyte subsets expressing granulysin were investigated in mucocutaneous lesions of BD. Serum granulysin levels were assayed by ELISA.

Results. Granulysin-positive cells were seen in specimens from oral ulcers, genital ulcers and acne-like eruptions, but not erythema nodosum-like lesions. Both CD4+ and CD8+ T cells expressed granulysin. Serum granulysin levels did not correlate with disease activity in BD.

Conclusion. Immune reactions mediated by granulysin-positive CTLs may play an important role in the pathogenesis of acne-like eruptions, oral ulcers and genital ulcers in BD.
Surveillance culture monitoring of double‐balloon enteroscopy reprocessing with high‐level disinfection
Authors: Chiu King‐Wah , Lu Long‐Sheng , Wu Keng‐Liang , Lin Ming‐Tzung , Hu Ming‐Luen , Tai Wei‐Chen , Chiu Yi‐Chun , Chuah Seng‐Kee , Hu Tsung‐Hui
Published: September 2011

Eur J Clin Invest 2012; 42 (4): 427–431

Background  Inadequate reprocessing of double‐balloon enteroscopy (DBE) or of endoscopic accessories may result in iatrogenic infections and present a risk to public health.

Aim  To use microbiological surveillance culture monitoring (SCM) to assess the adequacy of high‐level disinfection (HLD) with standard reprocessing procedures of DBE.

Materials and methods  We performed a prospective study on cultures collected from DBEs that had been treated by HLD by an automated endoscope washing machine (AEWM) decontamination cycle. This study included 42 cases with 57 cultures, which were collected consecutively between October 2009 and December 2010. In 31 cases, 31 cultures were collected from oral route DBE (mean patient age, 68·9 years), and in 23 cases, 26 cultures were collected from anal route DBE (mean patient age, 67·9 years). The results obtained were compared with those of our previous study of SCM on gastroscopy (GS) and colonoscopy (CS). The samples were collected by flushing 50 mL sterile distilled water into the suction channel and collecting the flow‐through in a sterile container. The samples were then incubated at 37 °C and examined for bacterial growth.

Results  Before HLD, the positive culture rate was 83·9% (26/31) for the oral route DBE and 100% (26/26) for the anal route DBE (P = 0·0406). After HLD, the positive culture rate was 12·9% (4/31) for the oral route DBE and 19·2% (5/26) for the anal route DBE (P > 0·05). A linear trend relationship was found between positive SCM and the length and category of diagnostic instruments – GS, CS, oral route DBE and anal route DBE.

Conclusions  Surveillance culture monitoring is a useful method to assess the effectiveness of HLD reprocessing of DBE. Machine washing may not achieve complete disinfection. Using AEWM regularly is mandatory to minimize cross‐contamination and to ensure quality assurance. Additional procedures are necessary to employ for the longer and anal route DBE.
A unique two‐way approach for the validation of total antioxidant capacity of serum samples
Authors: Prasetyo Endry N , Willibald Wonisch , Nyanhongo Gibson S. , Guebitz Georg M.
Published: September 2011

Eur J Clin Invest 2012; 42 (4): 432–438

Background  The human body is constantly exposed to a large variety of reactive oxygen species that are implicated in many pathophysiological conditions (atherosclerosis, cancer, neurodegenerative diseases etc.). Monitoring the antioxidant status of biological fluids could be used as an early warning sign ‘biomarker’ of possible disease onset. However, although several methods have been developed, questionable sensitivity, unreliability and non‐reproducibility hamper all, making it difficult to have an internationally accepted standardized method. This study presents and demonstrates the remarkable ability of a newly developed antioxidant capacity assay method based on tetramethoxy azobismethylene quinone (TMAMQ) to measure the total antioxidant capacity of serum samples using three complimentary approaches.

Design  Using an UV–Vis spectroscopy and oxygen sensor, the reduction of TMAMQ by serum antioxidants was compared to either the formation of syringaldazine or consumption of oxygen.

Results  After adding a fraction of human serum, 4·01 μM TMAMQ was reduced to syringaldazine from a stock of 11·74 μM TMAMQ. Subsequent addition of laccase resulted in the oxidation of the formed syringaldazine back to TMAMQ resulting in an increase in TMAMQ concentration to 11·71 μM (re‐establishing almost the same initial concentration of TMAMQ) while consuming 1·04 μM molecular oxygen.

Conclusions  The reduction of TMAMQ by serum samples is directly proportional to the consumption of oxygen and the formation of syringaldazine. This means that either the formation of syringaldazine or oxygen consumption can be used to validate or confirm data obtained through monitoring TMAMQ reduction.
Biogeochemical time lags may delay responses of streams to ecological restoration
Authors: HAMILTON STEPHEN K.
Published: September 2011

1. Mounting interest in ecological restoration of streams and rivers, including that motivated by the Water Framework Directive, has stimulated examination of whether management and restoration measures in streams and their catchments have yielded measurable improvements in ecological status (‘health’). Evidence for the efficacy of diffuse‐source pollution reduction (including best management practices on land) has proven elusive.

2. Several hydrological and biogeochemical processes delay the responses of streams and rivers to a decrease in nutrient and sediment inputs, potentially for decades. The implications of such time lags in response to restoration may not be well appreciated by restoration ecologists, regulators, sponsors of restoration work or the broader community.

3. The groundwater time lag results from the long residence time of ground water. This is particularly important with respect to nitrate, but is increasingly important for phosphorus (P) as well. Isotopic tracers and groundwater age dating suggest that stream water often is more than a decade old, and that several decades are required to flush most soluble contaminants from groundwater reservoirs.

4. Sediment movement through river networks can be protracted because of storage and remobilisation processes involving stream beds, impounded reaches and fringing bars and floodplains. In lowland streams and rivers, sediment accretion can be rapid, but its removal is often far slower and can take decades to centuries.

5. Phosphorus availability is subject to time lags because P tends to associate with minerals, resulting in a potentially large yet exchangeable P reserve in upland soils and alluvial and stream‐bed sediments. Thus, soils and sediments can remain rich in P for decades after new inputs are reduced, potentially acting as a source of P to surface waters. Phosphorus saturation of soils along groundwater percolation pathways can lead to even longer time lags. Restoration measures that inundate previously dry soils or desiccate previously inundated sediments can induce high rates of P release.

6. These hydrological and biogeochemical time lags can obscure the short‐term responses of streams and rivers to restoration measures. In many eutrophic waters, large decreases in nutrient availability would be required to return the ecosystem to a natural nutrient‐limited state, and this could take decades.
The relationship between in‐hospital mortality, readmission into the intensive care nursing unit and/or operating theatre and nurse staffing levels
Authors: Diya Luwis , Van den Heede Koen , Sermeus Walter , Lesaffre Emmanuel
Published: September 2011

diya l., van den heede k., sermeus w. & lesaffre e. (2011) The relationship between in‐hospital mortality, readmission into the intensive care nursing unit and/or operating theatre and nurse staffing levels. Journal of Advanced Nursing 68(5), 1073–1081.

Aim.  The aim of this article was to assess the relationship between (1) in‐hospital mortality and/or (2) unplanned readmission to intensive care units or operating theatre and nurse staffing variables.

Background.  Adverse events are used as surrogates for patient safety in nurse staffing and patient safety research. A single adverse event cannot adequately capture the multi‐dimensional attributes of patient safety; hence, there is a need to consider composite measures. Unplanned readmission into the postoperative Intensive Care nursing unit and/or operating Theatre and in‐hospital mortality can be viewed as measures that incorporate the effects of several adverse events.

Methods.  We conducted a Bayesian multilevel analysis on a subset of the 2003 Belgian Hospital Discharge and Nursing Minimum Data sets. The sample included 9054 patients who underwent coronary artery bypass surgery or heart valve procedures from 28 Belgian acute hospitals. Two proxies of patient safety were considered, namely postoperative in‐hospital mortality in the first postoperative intensive care unit and unplanned readmission into the intensive care and/or operating theatre (including mortality beyond the first postoperative intensive care unit) after the first‐operative intensive care nursing unit.

Results.  There is an association between in‐hospital mortality and/or unplanned readmissions and nurse staffing levels, but the relationship is moderated by volume and severity of illness respectively. In addition, the relationship differs between the two endpoints.

Conclusion.  Higher nurse staffing levels on postoperative general nursing cardiac surgery units protected patients from unplanned readmission to intensive care units or operating theatre and in‐hospital mortality.
Habitat isolation shapes the recovery of aquatic insect communities from a pesticide pulse
Authors: Trekels Hendrik , Van de Meutter Frank , Stoks Robby
Published: September 2011

1. The role of spatial processes in ecotoxicology is largely ignored. Yet, together with species‐specific sensitivities to the pollutant, spatial processes may determine community recovery and the resulting community composition after a pollution event.

2. We investigated the isolation‐specific potential for internal recovery by reproduction and external recovery by dispersal after a pesticide pulse in experimental aquatic insect communities along an isolation gradient.

3. External recovery was important in the univoltine species and in a multivoltine species that went locally extinct but only when a source population was nearby. Internal recovery occurred in all multivoltine species and was unexpectedly stronger in more isolated communities, probably because of release from a dispersal‐limited key predator.

4. As a result, community recovery and resulting changes in composition strongly depended on isolation and species differences in the potential for external recovery through dispersal and internal recovery through reproduction.

5. Synthesis and applications. Our results indicate that while the immediate impact of a toxicant on natural communities is shaped by species sensitivities, their recovery is primarily dependent on the degree of isolation. Risk assessment and the protection of communities under toxicant threat may improve greatly from considering the spatial context: isolated communities and communities with poor dispersers should receive extra protection to safeguard their member species. Ideally, land use planning should strive to remediate isolation of natural communities under threat in agricultural landscapes. Where this is not possible, spatial regulation of pesticide application may considerably improve protection of extant diversity.
Weak relationship between risk assessment studies and recorded mortality in wind farms
Authors: Ferrer Miguel , de Lucas Manuela , Janss Guyonne F. E. , Casado Eva , Muñoz Antonio R. , Bechard Marc J. , Calabuig Cecilia P.
Published: September 2011

1. Wind farms generate little or no pollution. However, one of their main adverse impacts is bird mortality through collisions with turbine rotors.

2. Environmental impact assessment (EIA) studies have been based on observations of birds before the construction of wind farms. We analysed data from 53 EIAs in relation to the actual recorded bird mortalities at 20 fully installed wind farms to determine whether this method is accurate in predicting the risk of new wind farm installations.

3. Bird data from EIAs were compared with bird collisions per turbine and year at functional post‐constructed wind farms to identify any relationship between pre‐ and post‐construction studies.

4. Significant differences in birds recorded flying among the 53 proposed wind farms were found by the EIAs. Similar results were obtained when only griffon vultures Gyps fulvus and other raptors were considered. There were significant differences in indexes, including the relative index of breeding birds close to proposed locations, among the 53 proposed wind farm sites.

5. The collision rate of birds with turbines was one of the highest ever recorded for raptors, and the griffon vulture was the most frequently killed species. Bird mortality varied among the 20 constructed wind farms.

6. No relationship between variables predicting risk from EIAs and actual recorded mortality was found. A weak relationship was found between griffon vulture and kestrel Falco sp. mortality and the numbers of these two species crossing the area.

7. Synthesis and applications. There was no clear relationship between predicted risk and the actual recorded bird mortality at wind farms. Risk assessment studies incorrectly assumed a linear relationship between frequency of observed birds and fatalities. Nevertheless, it is known that bird mortality in wind farms is related to physical characteristics around individual wind turbines. However, EIAs are usually conducted at the scale of the entire wind farm. The correlation between predicted mortality and actual mortality must be improved in future risk assessment studies by changing the scale of these studies to focus on the locations of proposed individual wind turbine sites and working on a species specific level.
Item response theory: How Mokken scaling can be used in clinical practice
Authors: Watson Roger , van der Ark L Andries , Lin Li‐Chan , Fieo Robert , Deary Ian J , Meijer Rob R
Published: September 2011

Aims.  To demonstrate the principles and application of Mokken scaling.

Background.  The history and development of Mokken scaling is described, some examples of applications are given, and some recent development of the method are summarised.

Design.  Secondary analysis of data obtained by cross‐sectional survey methods, including self‐report and observation.

Methods.  Data from the Edinburgh Feeding Evaluation in Dementia scale and the Townsend Functional Ability Scale were analysed using the Mokken scaling procedure within the ‘R’ statistical package. Specifically, invariant item ordering (the extent to which the order of the items in terms of difficulty was the same for all respondents whatever their total scale score) was studied.

Results.  The Edinburgh Feeding Evaluation in Dementia scale and the Townsend Functional Ability Scale showed no violations of invariant item ordering, although only the Townsend Functional Ability Scale showed a medium accuracy.

Conclusion.  Mokken scaling is an established method for item response theory analysis with wide application in the social sciences. It provides psychometricians with an additional tool in the development of questionnaires and in the study of individuals and their responses to latent traits. Specifically, with regard to the analyses conducted in this study, the Edinburgh Feeding Evaluation in Dementia scale requires further development and study across different levels of severity of dementia and feeding difficulty.

Relevance to clinical practice.  Good scales are required for assessment in clinical practice and the present paper shows how a relatively recently developed method for analysing Mokken scales can contribute to this. The two scales used as examples for analysis are highly clinically relevant.
How doctors practice evidence‐based medicine
Authors: Lu Yun‐Chieh , Li Ying‐Chun
Published: September 2011

Rationale and aims  Evidence‐based medicine (EBM) has gained worldwide attention. Many studies have used questionnaires to discuss factors obstructing the practice of EBM. However, no large‐scale data analysis has focused on who has practised EBM and when they practised it. This retrospective study aims to fill the research gap by applying nationally representative data to analyse EBM practice after the provision of new evidence regarding the prescription of rosiglitazone which has been shown to increase the risk of myocardial infarction.

Methods  We used the National Health Insurance Database in Taiwan to analyse the variations in rosiglitazone prescription among physicians. The study period was from the second quarter of 2007 to the fourth quarter of 2008. A total of 2536 physicians who prescribed rosiglitazone at least once were included in this study. We applied multivariate logistic analyses to predict the probability of physicians ceasing to prescribe rosiglitazone.

Results  We observed a significant improvement in EBM practice among specialists and experienced physicians. Endocrinologists were four times more likely to change rosiglitazone prescription habits than other specialists (odds ratio 4.129, 95% confidence interval 2.484–6.863). Doctors with more than 10 years of specialist experience performed better in EBM practice. Moreover, a prominent time lag with more than 6 months between EBM emergence and EBM practice was noticed.

Conclusions  Our study suggested that EBM was still not well practised, using rosiglitazone prescription as a study case. Further education and encouragement to strengthen physicians' EBM practice remain urgently needed within the medical community.
Family quality of life of Australian families with a member with an intellectual/developmental disability
Authors: Rillotta F. , Kirby N. , Shearer J. , Nettelbeck T.
Published: September 2011

Background  Family quality of life (FQOL) is a recent concept in intellectual/developmental disability research. Outcomes for the family are important to the provision of services because families, rather than institutions, are increasingly considered the primary support unit. This article presents Australian findings using the international Family Quality of Life Survey: Main Caregivers of People with Intellectual or Developmental Disabilities (FQOLS‐2006).

Method  Forty‐two South Australian main caregivers of people with an intellectual/developmental disability were interviewed using the FQOLS‐2006. The FQOL domains assessed were Health of the Family, Financial Well‐being, Family Relationships, Support from Other People, Support from Disability‐Related Services, Influence of Values, Careers, Leisure and Recreation, and Community Interaction. Domains were measured in terms of Importance, Opportunities, Attainment, Initiative, Stability and Satisfaction. The FQOLS‐2006 asked about the family's practical and emotional Support from Other People together, whereas the current study separated the constructs of practical and emotional support. Questions pertaining to FQOL in the past were also added, in order to gain a broader picture of present FQOL.

Results  Results indicated that families considered all the FQOL domains to be important. However, Health, Family Relationships and Financial Well‐being were regarded as slightly more important than Practical and Emotional Support from Others. The attainment of Family Relationships, Health, Values, and Leisure and Recreation were rated as quite a bit, but Practical Support from Other People was only rated as a little. Families were generally satisfied with all FQOL domains, but they were satisfied with their Family Relationships and they were neither satisfied or dissatisfied with their Financial Well‐being. Results also indicated that there was a need to distinguish between the provision of practical and emotional support from others, because the attainment of emotional support was rated at a slightly higher level than practical support.

Conclusions  The FQOLS‐2006 provided a comprehensive measure of FQOL, which, with some additional modifications, could be used to better inform service provisions and ultimately enhance the quality of life of people with intellectual/developmental disabilities and their families.
‘Painting a path to wellness’: correlations between participating in a creative activity group and improved measured mental health outcome
Authors: CADDY L. , CRAWFORD F. , PAGE A. C.
Published: September 2011

Accessible summary

Despite the long‐standing popularity of creative activity groups with mental health patients, there has been a lack of measurement evidencing a positive relationship between participation in such groups and improved mental health.

This study used de‐identified hospital records covering the period 2004–2009 to chart measured mental health outcomes for 403 patients attending a creative activity group in an acute inpatient psychiatric setting.

Four different clinical assessment tools were used to measure changes in mental health from admission to discharge for participants of the creative activity group.

Research findings establish that participation in creative activity positively correlates with improved mental health.

In the context of this research project, the term ‘creative activity’ includes participation in art, craft or expressive art‐based activity.

Responding to a call for quantitative outcome evidence about the therapeutic relationship between creative activity and mental health, this study examined the mental health outcomes of inpatients participating in art‐ and craft‐based creative therapies at a private psychiatric hospital over a 5‐year period. The creative activity group sample (n= 403) improved from admission to discharge across four different psychometric measures with moderate to strong mean effect sizes. Reductions from pre‐ to post‐treatment in both self‐reported and clinician‐rated symptoms are clearly demonstrated for the creative activity group participant sample. Research findings establish that participation in creative activity has potential benefits for people experiencing mental health problems.