bluuebunny/crossref_metadata_2025 huggingface dataset:
Superior 11-Year Survival but Higher Polyethylene Wear of Hydroxyapatite-Coated Mallory-Head Cups
Authors: Gottliebsen Martin , Rahbek Ole , Ottosen Per F. , Søballe Kjeld , Stilling Maiken
Published: February 2012

Hydroxyapatite (HA) coating of implant surfaces is believed to improve longevity of uncemented total hip arthroplasty (THA). However; it is speculated that HA particles may cause third body wear of the polyethylene (PE) liner with subsequent osteolysis and aseptic loosening of implants. We performed a retrospective comparison of two patient populations with cementless Mallory-Head acetabular components. The patients were identified in the Danish hip arthroplasty Registry (DHR); 77 patients had HA-coated cups and 73 patients had non-HA coated cups. Anteroposterior (AP) radiographs were analysed for PE wear, osteolysis was quantified and survival of the acetabular components was compared. The mean follow-up was 11 years.

There were no cup revisions in the HA group and 7 cup revisions in the non-HA group (p<0.01). The reason for revision in all cases was aseptic loosening of both stem and cup. The amount of osteolysis was significantly increased around cups in the non-HA group. The two-dimensional linear PE wear-rate of 0.18 mm/year was higher (p<0.001) in the group with HA coated cups compared with 0.12 mm/ year in the group with non-HA coated cups. The mean age was lower (P=0.001) in the HA group (57 years) compared with the non-HA group (63 years).

After 11.1 years of follow-up non-HA coated cups had a higher revision rate. Increased PE wear with HA-coated cups did not have a negative influence on the revision rate, but may result in a need for revision surgery over time.
The Burch-Schneider Cage: 9-Year Survival in Paprosky Type 3 Acetabular Defects. Clinical and Radiological Follow-Up
Authors: Jones Luke , Grammatopoulos George , Singer Gian
Published: February 2012

Revision hip arthroplasty in cases with severe acetabular deficiency represents a technical challenge. The aim of this study was to determine:

1. The 9-year survival of the Burch Schneider anti-protrusio cage (BS-APC) in severe acetabular defects.

2. The migration of the cage and correlation of this with functional outcome.

3. The anticipated functional outcome users can expect in a district general hospital setting in the management of severe acetabular defects.

A single-surgeon consecutive series of 30 complex acetabular reconstructions using the BS-APC was retrospectively reviewed. Clinical and radiological follow up at 5–9 years was obtained. Survival was established with revisions and further surgery as different end-points. A radiological analysis using ein bilt roentgen analyse (EBRA) was performed.

At a mean follow-up of 85 months (range: 64–118) 26 patients (87%) were alive. Nine-year survival was 95% for revision of BS-APC as an end-point and 92% with any cause of further surgery as an endpoint. The mean Oxford Hip Score was 34.5 and UCLA activity score was 4.4. All cases demonstrated evidence of significant migration, but no screws were found to be broken. There was no correlation between cup migration and Oxford hip score (p=0.07).

Our non-specialist centre experience suggests the BS-APC should not be dismissed as a reconstruction option in the most severe acetabular defects.
Mortality and Morbidity following Hip Fractures Related to Hospital Thromboprophylaxis Policy
Authors: Heidari Nima , Jehan Shah , Alazzawi Sulaiman , Bynoth Sharon , Bottle Alex , Loeffler Mark
Published: February 2012

Chemical thromboprophylaxis has been shown to reduce the incidence of venous thromboembolism (VTE) for patients with fractures of the hip, but it is not known with certainty whether it use also reduces mortality.

Using postal and telephone questionnaires we collected data from English National Health Service (NHS) hospitals about their thromboprophylaxis policy for hip fractures patients from April 2003 to April 2007. Using Hospital Episode Statistics (HES) we ascertained in-hospital mortality rates at 30 days and at one year following admission to hospital. Unplanned hospital readmission rates for all causes (including episodes of thromboembolism and bleeding) within 30 days (all years) and one year (2003 to 2005) were also established.

A total of 150 hospitals were contacted and data gathered from 62 hospitals (response rate 41.3%) There were 255841 patients with neck of femur fractures during this five year period who were assessed for morbidity and mortality, and we correlat these with thromboprophylaxis policy. There was no significant difference in hospital readmission within 30 days, or diagnosis of thromboembolism or haemorrhage among hospitals with different thromboprophylaxis policies. The hospitals using low molecular weight heparin (LMWH) in half the dose recommended by the British National Formulary had significantly reduced mortality in-hospital (odds ratio (OR) 0.79, 95% CI 0.69–0.90, P=0.0006), at 30 days (OR 0.8 (0.70 – 0.92), P=0.001) and at one year (OR 0.89 (0.80 – 1.00), P=0.050), compared with those with no such policy.

Our data suggest that the thromboprophylaxis regimen for patients with fracture neck of femur should be half dose LMWH for the duration of the hospital stay.
Flow Competition between Hepatic Arterial and Portal Venous flow during Hypothermic Machine Perfusion Preservation of Porcine Livers
Authors: Monbaliu Diethard R. , Debbaut Charlotte , Hillewaert Wim J. , Laleman Wim J. , Sainz-Barriga Mauricio , Pirenne Jacques , Segers Patrick
Published: February 2012

Hypothermic machine perfusion (HMP) is regarded as a better preservation method for donor livers than cold storage. During HMP, livers are perfused through the inlet blood vessels, namely the hepatic artery (HA) and the portal vein (PV). In previous HMP feasibility studies of porcine and human livers, we observed that the PV flow decreased while the HA flow increased. This flow competition restored either spontaneously or by lowering the HA pressure (PHA). Since this phenomenon had never been observed before and because it affects the HMP stability, it is essential to gain more insight into the determinants of flow competition. To this end, we investigated the influence of the HMP boundary conditions on liver flows during controlled experiments. This paper presents the flow effects induced by increasing PHA and by obstructing the outlet blood vessel, which is the vena cava inferior (VCI).

Flow competition was evoked by increasing PHA to 55–70 mmHg, as well as by obstructing the VCI. Remarkably, a severe obstruction resulted in a repetitive and alternating tradeoff between the HA and PV flows. These phenomena could be related to intra-sinusoidal pressure alterations. Consequently, a higher PHA is most likely transmitted to the sinusoidal level. This increased sinusoidal pressure reduces the pressure drop between the PV and the sinusoids, leading to a decreased PV perfusion. Flow competition has not been encountered or evoked under physiological conditions and should be taken into account for the design of liver HMP protocols. Nevertheless, more research is necessary to determine the optimal parameters for stable HMP.
Experiencing Experiments: A Multiplayer Game for Sharing Ideas
Authors: Curley Martin , Formica Piero
Published: February 2012

In this latest in a series of articles on the innovative use of experimental business laboratories for high-expectation entrepreneurs, the authors focus on the networking benefits of business lab experiments. Distinguishing between ‘Robinson Crusoe’ types, whose tendency is to operate in isolation, and ‘Lemuel Gulliver’ types, who rely on interaction with others, they suggest that engaging Crusoe entrepreneurs in the open participatory environment of the experimental laboratory encourages them to discard their bad habit of working in a closed environment in favour of interaction and sharing. This, the authors argue, is an essential change in light of the evolving process of innovation, which is moving from a closed process through an open one towards a future in which competing innovation networks become the norm. They demonstrate the nature of contemporary entrepreneurship and innovation by drawing analogies from physics and the article closes with a case study of their theory in practice.
Knowledge Transfer between SMEs and Higher Education Institutions
Authors: Delfmann Heike , Koster Sierdjan
Published: February 2012

Knowledge transfer (KT) between higher education institutions (HEIs) and businesses is seen as a key element of innovation in knowledge-driven economies: HEIs generate knowledge that can be adopted in the regional economy. This process of valorization has been studied extensively, mainly with a focus on universities. In the Netherlands, there is a binary system of higher education comprising universities and the more practice-oriented colleges of higher education. From 2001 these colleges have played an increasingly important role in KT, which gives rise to the question of whether there are differences in the frequency and structure of KT involving universities and KT involving colleges. Colleges appear easier to access for SMEs, because of their focus on business practices. The interactions between universities and SMEs are more localized, suggesting the need for face-to-face interactions in those contacts. Furthermore, the results reiterate the importance of the absorptive capacity of firms and previously established contacts of entrepreneurs in explaining firm–HEI interaction.
Balancing the Yin and Yang: The Role of Universities in Developing Softer Skills in Accountancy
Authors: Evans Carl , Gbadamosi Gbolahan , Wells Jamie , Scott Ian
Published: February 2012

This paper presents an examination of the importance of softer skills in the accountancy profession and a discussion of the contribution that universities can make in supporting the development of these skills. With employers increasingly demanding a greater range of softer skills such as effective communication, the paper is intended to challenge universities to reflect on whether they are maximizing the opportunity to prepare individuals for a career in the accountancy profession. The authors suggest that university lecturers teaching accountancy studies may need to adopt alternative learning methodologies, such as enquiry-based learning, to develop students' softer skills effectively.
Magnetoresistance of Planar Heterostructures Approached on a Theoretical Basis
Authors: Olszewski Stanisław , Roliński Tomasz
Published: February 2012

The change of magnetoresistance in dependence on the strength of the magnetic induction is examined theoretically for several heterostructures taken as examples. Different temperatures of the examined samples, concentrations of the electron or hole carriers, and band structure properties are then involved. A general result is that a linear increase of magnetoresistance as a function of the magnetic induction should be obtained for all samples. This finds its counterpart in the behaviour of the experimental data. The ratios of the theoretical slopes of increase to the experimental ones range between 0.1 and 11, but the average ratio amounts to less than 1.8.
Nearly Unattenuated Charge Density Wave Transport in a Linear Chain Conductor Fabricated by Spark Discharge
Authors: Arendt Peter
Published: February 2012

Chemical preparation techniques have proved in the past unsuitable for the synthesis of linear chain conductors which are said to exhibit anomalously large electrical conductivities via moving charge density waves (CDWs) which are depinned from the underlying linear ionic lattice and move in a direct current (DC) electric field nearly unattenuated. We present a novel technique which uses only purely physical processes to fabricate linear chain conductors which seem to meet all claims laid by the CDW mechanism of conductivity in its ideal form. A spark engraves in an originally low-conducting nonlinear silver-based material, driven far from equilibrium beyond some critical power input, a discharge pattern, inside the branches of which chains of Ag+-ions run which form a high-conducting current path, along which CDWs may propagate nearly unattenuated. The material obtained exhibits an electrical conductivity which is by four orders of magnitude higher than the conductivity of metallic silver. A simple model is presented to explain this high conductivity and some related phenomena associated with electrical conduction via a moving CDW
Climatology of line‐shaped rainbands over northern Japan in boreal summer between 1990 and 2010
Authors: Yamada Tomohito J. , Sasaki Jun , Matsuoka Naoki
Published: February 2012

Line‐shaped rainbands (LRBs) are severe storm events that cause torrential rainfall across the mid‐latitudes and are difficult to accurately predict because of their complex physical processes. We examined the occurrence of LRBs in boreal summer in northern Japan over the period 1990–2010. In years with anomalously many LRBs, the development of LRBs over northern Japan was driven by a combined positive anomaly of warm sea‐surface temperatures and westerly moisture flux associated with the prominent pattern of the surface pressure anomalies between the main island of Japan and the Sea of Okhotsk. In contrast, the number of LRBs were significantly small with opposite characteristics. Copyright © 2012 Royal Meteorological Society
The mystery of C. elegans aging: An emerging role for fat
Authors: Ackerman Daniel , Gems David
Published: February 2012

New C. elegans studies imply that lipases and lipid desaturases can mediate signaling effects on aging. But why might fat homeostasis be critical to aging? Could problems with fat handling compromise health in nematodes as they do in mammals? The study of signaling pathways that control longevity could provide the key to one of the great unsolved mysteries of biology: the mechanism of aging. But as our view of the regulatory pathways that control aging grows ever clearer, the nature of aging itself has, if anything, grown more obscure. In particular, focused investigations of the oxidative damage theory have raised questions about an old assumption: that a fundamental cause of aging is accumulation of molecular damage. Could fat dyshomeostasis instead be critical?
Nonlinear Model Predictive Control of a CO2 Post‐Combustion Absorption Unit
Authors: Åkesson J. , Laird C. D. , Lavedan G. , Prölß K. , Tummescheit H. , Velut S. , Zhu Y.
Published: February 2012

A dynamic model of a chemical CO2 absorption process with aqueous monoethanolamine (MEA) is presented, validated against experimental data. Based on the validated model, a reduced‐order model is developed, suitable for an online optimization control strategy. The objective of the optimization is to enable fast adaptations to changes in operating conditions of the power plant, while minimizing the energy consumption in the operation of the CO2 separation plant. The results indicate that model‐based online optimization is a feasible technology for control of CO2 separation systems.
Population structure increases the evolvability of genetic algorithms
Authors: Hol Felix J. H. , Wang Xin , Keymer Juan E.
Published: February 2012

Populations are shaped by the spatial structure of their environment: space organizes interactions between individuals locally, and gives rise to a global population structure. Both local and global population structures can have a profound influence on the evolutionary dynamics of a population. To characterize this influence, we use genetic algorithms with several distinct contact structures to evolve cellular automata, which perform a density classification task. We find that local contact structures (modeled as graphs with various topologies) that limit the number of breeding partners show greater evolvability than well‐mixed populations. Furthermore, we show that the evolvability of well‐mixed populations is enhanced in a metapopulation setting of coupled subpopulations. © 2012 Wiley Periodicals, Inc. Complexity, 2012
ON THE CHOICE OF HEALTH INEQUALITY MEASURE FOR THE LONGITUDINAL ANALYSIS OF INCOME‐RELATED HEALTH INEQUALITIES
Authors: Allanson Paul , Petrie Dennis
Published: February 2012

Changes in rank‐dependent income‐related health inequality measures over time may usefully be decomposed into contributions due to changes in health outcomes and changes in individuals' positions in the income distribution. This paper establishes the normative implications of this type of decomposition by embedding it within a broader analysis of changes in the ‘health achievement’ index. We further show that the choice of health inequality measure implies a particular vertical equity judgement, which may be expressed on a common scale in terms of the concentration index of health changes that would be inequality preserving. We illustrate the empirical implications of this choice by reporting results from a longitudinal analysis of changes in income‐related health inequality in Great Britain using the concentration, the Erreygers and Wagstaff indices of health attainments and the concentration index of health shortfalls. Copyright © 2012 John Wiley & Sons, Ltd.
The Colleges Train Radiomen
Authors: DUNHAM FRANKLIN
Published: February 2012

What employment opportunities do radio and television offer? How are schools and colleges preparing their graduates for work in radio? What are the prospects for the development of educational broadcasting? What type of individual is most likely to succeed in radio? These are important questions to thousands of young people today. They are answered in this provocative article which will be of interest to all concerned with the educational and vocational guidance of youth.
Nanoscale distinction of membrane patches – a TERS study of Halobacterium salinarum
Authors: Deckert‐Gaudig Tanja , Böhme René , Freier Erik , Sebesta Aleksandar , Merkendorf Tobias , Popp Jürgen , Gerwert Klaus , Deckert Volker
Published: February 2012

The structural organization of cellular membranes has an essential influence on their functionality. The membrane surfaces currently are considered to consist of various distinct patches, which play an important role in many processes, however, not all parameters such as size and distribution are fully determined. In this study, purple membrane (PM) patches isolated from Halobacterium salinarum were investigated in a first step using TERS (tip‐enhanced Raman spectroscopy). The characteristic Raman modes of the resonantly enhanced component of the purple membrane lattice, the retinal moiety of bacteriorhodopsin, were found to be suitable as PM markers. In a subsequent experiment a single Halobacterium salinarum was investigated with TERS. By means of the PM marker bands it was feasible to identify and localize PM patches on the bacterial surface. The size of these areas was determined to be a few hundred nanometers. (© 2012 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Egg morphology of nine species of pollenia robineau‐desvoidy, 1830 (Diptera: Calliphoridae)
Authors: Grzywacz Andrzej , Szpila Krzysztof , Pape Thomas
Published: February 2012

Egg morphology of nine species of the cluster fly genus Pollenia Robineau‐Desvoidy was studied with scanning electron microscopy. Funnel‐shaped micropylar area, chorion covered with centrally depressed hexagons, well developed hatching pleats on the dorsal surface encompassing the median area were found in eggs of all species: P. amentaria (Scopoli), P. angustigena Wainwright, P. atramentaria (Meigen), P. labialis Robineau‐Desvoidy, P. mayeri Jacentkovsky, P. pediculata Macquart, P. rudis (Fabricius), P. similis (Jacentkovsky), and P. vagabunda (Meigen). Untypical for Calliphoridae, a dual morphological structure of plastron‐bearing area is described here for the first time. On the basis of our observations, all species studied share the presence of a plastron respiratory function on the entire surface between the hatching lines. Differences between species were found in the shape of the longitudinal hatching pleats and the proportion between ‘island pattern’ and ‘hexagonal pattern’ of their chorionic surface, and in the intensity of perforation of hexagons of the median area. Comparisons of Pollenia egg morphology with that of other representatives of Calliphoridae revealed its unique structure, allowing easy differentiation from other representatives of the family. Microsc. Res. Tech. 2012. © 2012 Wiley Periodicals, Inc.
Meta‐analysis: Multidisciplinary fall prevention strategies in the acute care inpatient population
Authors: DiBardino David , Cohen Elaine R. , Didwania Aashish
Published: February 2012

BACKGROUND:

Inpatient falls are common adverse events that lead to inpatient injury, increased length of stay, healthcare costs, litigation, and are a focus of patient safety and healthcare quality. Fall prevention methods are currently evolving to address the problem.

PURPOSE:

To examine the available data evaluating multidisciplinary fall prevention strategies in the acute inpatient setting.

DATA SOURCES:

A complete literature search of MEDLINE, CINAHL, EMBASE and the Cochrane Library through December 2011 was used. The bibliographies of all systematic reviews and meta‐analyses were hand searched.

STUDY SELECTION:

Only primary research studies relating to acute care inpatient hospital multidisciplinary fall prevention were included. Selected papers were assessed for quality by 2 authors using a 20‐point scale previously used in the fall literature.

DATA EXTRACTION:

Each selected study was carefully hand searched by 2 authors for the purposes of data extraction. Study results, in fall rate per 1000‐patient days, and the characteristics of the interventions used were extracted for analysis.

DATA SYNTHESIS:

Effect sizes (odds ratios) and 95% confidence intervals were derived for individual studies and then combined across research reports using a random‐effects meta‐analysis.

CONCLUSIONS:

Fall prevention strategies have a significant but small effect on fall rates despite the use of complex, multidisciplinary interventions. Additional randomized trials are needed to examine the possible benefits of multidisciplinary fall prevention strategies in the acute inpatient setting. Journal of Hospital Medicine 2012; © 2012 Society of Hospital Medicine
Following the Crystallization Process of Polyethylene Single Chain by Molecular Dynamics: The Role of Lateral Chain Defects
Authors: Sanmartín Sara , Ramos Javier , Martínez‐Salazar Javier
Published: February 2012

Summary: Langevin molecular dynamics (LMD) simulations have been performed in order to understand the role of the short chain branches (SCB) on the formation of ordered domains by cooling ethylene/α‐olefins single chain models. Different long single‐chain models (C2000) with 0, 5 and 10 branches each 1000 carbons were selected. The branches were randomly distributed along the backbone chain. Furthermore, C1 (methyl) and C4 (butyl) branches were taken into account. These models mimic the molecular architecture of ethylene/1‐butene and ethylene/1‐hexene random copolymers. The simulations are performed according to the following protocol: 20 random chain conformations for each model were equilibrated at high temperature (T* = 13.3) and then they were cooled in steps of 0.45 until the final temperature (T* = 6.2) by running a total of 35 × 106 LMD steps. The distribution peaks of crystallization for each model were calculated by differentiating the global order parameter with respect to the temperature. The Tc* (crystallization temperature) decrease as the number of branches increases as it is experimentally observed. The formation of order in the copolymers is affected by the type and amount of the SCB in the backbone of the polymer chain. The stem lenght and crystallization fraction (α) were defined using the local‐bond order parameter. Both parameters decrease as the number of branches increase. In all cases here shown, the C4 branches are excluded from the ordered domains. However, we have observed that the methyl branch can be incorporated into the ordered regions. These facts satisfactorily agree with experimental data available in the literature.
Meta‐analysis of self‐reported substance use compared with laboratory substance assay in general adult mental health settings
Authors: Large Matthew M. , Smith Glen , Sara Grant , Paton Michael B. , Kedzior Karina Karolina , Nielssen Olav B.
Published: February 2012

An accurate assessment of substance use is necessary to make a correct psychiatric diagnosis and to provide appropriate treatment. This study uses meta‐analysis to establish the strength of the association between self‐reported substance use and the results of laboratory substance assay including the testing for specific substances and screening for any substance use in psychiatric hospitals and in community mental health settings.

A systematic search for published studies was supplemented by additional data required for meta‐analysis provided by several researchers in this field. Using random‐effects meta‐analysis, we calculated the pooled estimate of the odds ratio of a positive substance assay in patients reporting use or non‐use of substances and estimated the sensitivity, specificity, positive predictive value and negative predictive value.

Twenty‐six studies met the inclusion criteria. Very strong associations were found between self‐reported use and positive tests for cannabis [N = 11 studies, odds ratio (OR) = 22.3; 95% confidence interval (CI) = 10.1–49.1], amphetamines (N = 8, OR = 26.6; 95% CI = 7.9–88.9), cocaine (N = 8, OR = 39.7; 95% CI = 16.2–97.2) and opiates (N = 7, OR = 83.5; 95% CI = 26.7–260.7). Strong associations were found between self‐reported use of any substance and positive substance screening (N = 15, OR = 7.2, 95% CI = 3.6–14.1) and tests for alcohol use (N = 5, OR = 8.5; 95% CI = 2.5–28.4). Screening for any substance use had a sensitivity of 61% and a specificity of 66%. Testing for individual substances was specific but lacked sensitivity.

Screening has the potential to detect clinically relevant substances that would not be reported by the patient, whereas testing for a specific substance has little advantage over self‐report. The sensitivity of the substance assay might be improved by obtaining a sample at the earliest opportunity. Consideration should be given to the increased use of substance screening in general adult mental health settings because it could improve the accuracy of psychiatric diagnosis and increase the likelihood of patients receiving treatment for substance use disorders. Copyright © 2012 John Wiley & Sons, Ltd.
Urinary metabonomic study using a CUMS rat model of depression
Authors: Liu Xiao‐Jie , Li Zhen‐Yu , Li Zhong‐Feng , Gao Xiao‐Xia , Zhou Yu‐Zhi , Sun Hai‐Feng , Zhang Li‐Zeng , Guo Xiao‐Qing , Du Guan‐Hua , Qin Xue‐Mei
Published: February 2012

Chronic unpredictable mild stress (CUMS) is a well‐validated model of depression. In this study, a urinary metabonomics method based on the NMR spectrometry was used to study the metabolic perturbation in CUMS‐induced rat depression model. With pattern recognition analysis, a clear separation of CUMS rats and healthy controls was achieved, and nine endogenous metabolites contributing to the separation were identified. CUMS‐treated rats were characterized by the increase of glycine, pyruvate, glutamine, and asparagines, as well as the decrease of 2‐oxoglutarate, dimethylglycine, citrate, succinate, and acetate. The urinary biochemical changes related to the metabolic disturbance in CUMS induced depression, and the possible correlations with live qi stagnation in traditional Chinese medicine are discussed. The work shows that CUMS is a reliable model for studying depression, and the noninvasive urinary metabolomic method is a valuable tool to investigate the biochemical pertubations in depression as an early diagnostic means. Copyright © 2012 John Wiley & Sons, Ltd.
1H NMR spectroscopic identification of protonable sites in cryptolepines with C‐11 substituents containing two amino functionalities
Authors: Lavrado João , Paulo Alexandra , Bichenkova Elena , Douglas Kenneth T. , Moreira Rui
Published: February 2012

Knowledge of protonable sites and acid dissociation constants of cryptolepine derivatives having C‐11 substituents containing two amino functionalities is of great importance to the understanding of the mechanism of their antimalarial action, which may contribute to their further development as drug candidates. In this work, we applied 1H NMR titration to investigate the acid–base characteristics of these polyprotic compounds in the pH range 3–13. We identified three acid–base equilibria with most acid dissociation constants (pKa*) being greater than 10.5, which prevented us from using the potentiometric method. Overall, 1H NMR titration was sensitive and suitable for the determination of pKa values for these drug leads. Copyright © 2012 John Wiley & Sons, Ltd.
Experimental observation of two‐layer TiO2 nanotube arrays prepared by stepping‐voltage anodization
Authors: Ding Jietao , Xiao Zhanwen , Fan Hongsong
Published: February 2012

Two‐layer TiO2 nanotube arrays were produced by stepping down the anodic voltage during which three nanotube interface structures between the top layer and the second layer were observed by SEM. We detected a polygonal ring structure on the top surface of the second layer and offer direct evidence of the growth of this second tube layer both at the cell boundary and right beneath the bottom of the first tube layer. For these processes, a possible growth mechanism is presented. (© 2012 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Electromagnetic navigation platform for endovascular surgery: how to develop sensorized catheters and guidewires
Authors: Condino S. , Ferrari V. , Freschi C. , Alberti A. , Berchiolli R. , Mosca F. , Ferrari M.
Published: February 2012

Background

Endovascular procedures are nowadays limited by difficulties arising from the use of 2D images and are associated with dangerous X‐ray exposure and the injection of nephrotoxic contrast medium.

Methods

An electromagnetic navigator is proposed to guide endovascular procedures with reduced radiation dose and contrast medium injection. Five DOF electromagnetic sensors are calibrated and used to track in real time the positions and orientation of endovascular catheters and guidewires, while intraoperative 3D rotational angiography is used to acquire 3D models of patient anatomy. A preliminary prototype is developed to prove the feasibility of the system using an anthropomorphic phantom.

Results

The spatial accuracy of the system was evaluated during 70 targeting trials obtaining an overall accuracy of 1.2 ± 0.3 mm; system usability was positively evaluated by three surgeons.

Conclusions

The strategy proposed to sensorize endovascular instruments paves the way for the development of surgical strategies with reduced radiation dose and contrast medium injection. Further in vitro, animal and clinical experiments are necessary for complete surgical validation. Copyright © 2012 John Wiley & Sons, Ltd.
MACROINVERTEBRATE–PRESSURE RELATIONSHIPS IN BOATABLE NEW ZEALAND RIVERS: INFLUENCE OF UNDERLYING ENVIRONMENT AND SAMPLING SUBSTRATE
Authors: Collier Kevin J. , Clapcott Joanne E. , David Bruno O. , Death Russell G. , Kelly David , Leathwick John R. , Young Roger G.
Published: February 2012

Responses of macroinvertebrate communities to human pressure are poorly known in large rivers compared with wadeable streams, in part because of variable substrate composition and the need to disentangle pressure responses from underlying natural environmental variation. To investigate the interaction between these factors, we sampled macroinvertebrates from the following: (i) submerged wood; (ii) littoral substrates < 0.8 m deep; and (iii) inorganic substrates in deep water (> 1.5 m) benthic habitats in eleven 6th‐ or 7th‐order New Zealand rivers spanning a catchment vegetation land cover gradient. Cluster analysis identified primary site groupings reflecting regional environmental characteristics and secondary groupings for moderate gradient rivers reflecting the extent of catchment native vegetation cover. Low pressure sites with high levels of native vegetation had higher habitat quality and higher percentages of several Ephemeroptera and Trichoptera taxa than sites in developed catchments, whereas developed sites were more typically dominated by Diptera, Mollusca and other Trichoptera. Partial regression analysis indicated that the combination of underlying environment and human pressure accounted for 77–89% of the variation in Ephemeroptera, Trichoptera and Plecoptera taxa richness, %Diptera and %Mollusca, with human pressure explaining more variance than underlying environment for %Mollusca. Analysis of replicate deepwater and littoral samples from moderate gradient sites at the upper and lower ends of the pressure gradient indicated that total Trichoptera and Diptera richness and %Diptera responded to land use differences in these boatable river catchments. Responses to human pressure were substrate specific with the combination of littoral and deepwater substrates providing the most consistent response and yielding the highest number of taxa. These results indicate that multiple substrate sampling is required to document the biodiversity and condition of boatable river macroinvertebrate communities and that spatial variation in the underlying natural environment needs to be accounted for when interpreting pressure–response relationships. Copyright © 2012 John Wiley & Sons, Ltd.
Providing a Sounding Board for Second Language Writers
Authors: Kim E. Julia
Published: February 2012

English as a second language (ESL) writing teachers face distinct challenges as they try to help students write in the language that is appropriate and natural to the native‐English‐speaking audience. It is disheartening when the writings of even advanced‐level second language students often contain many awkward sentences and non‐English‐like patterns. ESL writers face various linguistic challenges as they write, and they should be allowed to navigate through the writings of others to attend to the linguistic features they may need in order to accurately express their thoughts. ESL writing teachers can help students by providing language support, through models and prewriting activities, that will encourage students to recognize certain linguistic forms and stock phrases used by native‐English‐speaking writers. The support of a writing center is also essential because a writing center not only introduces students to the academic community, but also serves as a forum where students can negotiate meanings and discover correct language forms so that they can then convey them.
I'm a Poet? International Doctoral Students at a U.S. University Participate in a Creative Writing Workshop
Authors: Ostrow Jill , Ning Chang Lynn Chih
Published: February 2012

What happens when international doctoral students participate in a creative writing workshop? Very often, students at our large midwestern U.S. university enter classes having learned English in their native countries with a heavy emphasis on only skills and grammar. They have not had the chance to play with language, to express themselves through poetry, narrative, or expressive voice. One of the authors created the course Writing Workshop for International Graduate Students so doctoral students from different countries would be able to come together not only as a community of writers learning English, but as a community of international writers. The students were asked to turn off their academic writing voices and to explore their creative ones. Slowly, through the writing process of choice, drafting, sharing, editing, revision, and drafting in other genres, the students began to feel more confident as writers. Several discovered that they were poets. Others were willing to take the risk to try different genres. All of the students felt that their academic writing had improved. The authors’ findings suggest that it is crucial to allow opportunities for international students to write creatively in both their native and nonnative languages in order to help them succeed in all of their university courses.

Practice always embodies theory and theory strives for understanding of practice. Critical approaches to education, understood as both theory and practice, aim to identify and challenge inequitable social structures and policies. (Cummins, 2009, pp. 261‐271)
Writing It Down: Issues Relating to the Use of Restitution Tasks in Listening Comprehension
Authors: Prince Peter
Published: February 2012

One common way of assessing learners’ proficiency in second language (L2) listening comprehension is by comprehension‐restitution (C‐R), whereby learners write down what they have heard. The various forms of C‐R differ according to characteristics of the input (e.g., length, speech rate) and of the output (e.g., amount of detail requested). The procedure may thus make different demands in terms of how the input is processed and written down. Analysis of the C‐R procedure raises issues both about the assessment and teaching of listening comprehension and about the processes involved in the accomplishment of the task. The performance of eight French learners of English was examined, and discussed in interviews, with regard to three C‐R tasks: paragraph restitution, sentence completion, and summarising. The criteria adopted were word recognition, intelligibility of answers, and task accomplishment. Results show that a high percentage of words needs to be recognised before the task can be accomplished, but that top‐down processes can help in reaching an intelligible answer. Implications for teaching are discussed.
Making the Implicit Explicit: Raising Pragmatic Awareness in Trainee Interpreters Using Semiauthentic Spontaneous Discourse Samples
Authors: Sachtleben Annette , Denny Heather
Published: February 2012

Following the recent interest in the teaching of pragmatics and the recognition of its importance for both cross‐cultural communication and new speakers of an additional language, the authors carried out an action research project to evaluate the effectiveness of a new approach to the teaching of pragmatics. This involved the use of semiauthentic discourse samples of New Zealand English to raise the pragmatic awareness of trainee interpreters in an undergraduate course taught by the first author. The researchers analysed qualitative data from learner blogs, written during instruction as part of the course requirements, for evidence that the learners noticed paralinguistic features used for pragmatic effect in conversations they overheard or took part in outside the classroom. The class teacher also kept a reflective journal recording her observations on learner progress and the usefulness of the materials. The researchers found there was a growth in the number of learners noticing pragmatic features during tuition, suggesting that the semiauthentic samples were effective as learning tools. Use of these samples also facilitated the noticing and discussion of cross‐cultural differences and enabled more learner‐centered methodology to be used.
Fatty Acid Contents in Fractions of Neutral Lipids and Phospholipids of Fillets of Tilapia Treated with Flaxseed Oil
Authors: Tonial Ivane Benedetti , Matsushita Makoto , Furuya Wilson Massamitu , de Souza Nilson Evelázio , Visentainer Jesuí Vergílio
Published: February 2012

The fatty acid composition in fractions of neutral lipids (NL) and phospholipids (PL) of the lipid content of muscle tissue of tilapia (Oreochromis niloticus) fed diets enriched with 7% of flaxseed oil was evaluated. Lipid profiles were evaluated every 15 days over 90 days. NL were predominant, with saturated and monounsaturated fatty acids being the major ones, and the PL fraction showed a great amount of polyunsaturated fatty acids (PUFA). The PUFA/SFA ratio values were lower in the NL fraction, ranging from 0.3 to 0.6, when compared to the PL fraction, which ranged from 1.0 to 1.1. The n‐3 PUFA concentrations increased from the beginning of the treatment up to 90 days of treatment, while the n‐6 PUFA concentrations decreased in the same period, thus improving the n‐6/n‐3 ratio of lipid content. The n‐6/n‐3 ratios in the NL class varied from 11.1 to 1.1 and in the PL class from 4.6 to 1.0, which contributed to an increase in the nutritional value of the fish meat. The PUFA/SFA ratio values increased during the treatment, whereas the n‐6/n‐3 ratios decreased. Thus, the addition of flaxseed oil to the tilapia diet led to an improvement in the quality of the fish meat in terms of physiological and nutritional properties.
Security in Niamey: an anthropological perspective on policing and an act of terrorism in Niger
Authors: Göpfert Mirco
Published: February 2012

The abduction of two Frenchmen in January 2011 in Niamey's supposedly most secure neighbourhood has led many to question the functioning of the city's security apparatus. This paper analyses Niamey's security landscape, initially from an historical and then from a spatial perspective. It argues that for a comprehensive analysis of security, we must first decentre our perspective on security construction, and thus take informal non-organised modes of policing just as seriously as policing by state and vigilante organisations; and second, take into account the inseparability of sociality and security, a fragile balance of trust and acceptable risk. In conclusion I argue that this focus may be one way of comprehending the kidnapping: how was it possible and what were its implications for Niamey's security landscape?
Experimental evaluation of protons emission from a plasma focus device
Authors: BHUYAN M. , MOHANTY S. R.
Published: February 2012

Solid state nuclear track detectors have been used for measuring axially emitted protons from a 2.2-kJ energy plasma focus device. The flux of the protons emerging out from the pinched plasma column of the plasma focus device has been found to saturate the CR-39 detectors. Aluminum filters have been used to avoid the saturation effect. By varying the aluminum filter thickness as well as the etching time of CR-39 detectors, proton tracks have been analyzed. Proton energy above 200 keV to about 1 MeV has been measured by using different thicknesses of aluminum filters. On increasing the etching hours, the most probable track diameter is found to be shifted from lower to higher values. The track number density decreases on increase of the filter thickness, whereas the track diameters increase linearly with respect to the etching time.
DE L'USAGE DES CONIQUES CHEZ IBRĀHĪM IBN SINĀN
Authors: Bellosta Hélène
Published: February 2012

Once Apollonius'Conicshad been translated from Greek into Arabic, they became a main reference and the principal tool in studying solid problems, algebraic equations of 3rdand 4thdegrees, infinitesimal mathematics, etc. Mathematicians of the 9th–10thcenturies also studied the conic sections' constructions, as well as their continuous drawing and their drawing by points. Ibrāhīm ibn Sinān (909–946), as his grandfather Thābit ibn Qurra (826–901), was one of the most active and inventive mathematicians in these fields. Late Hélène Bellosta examined in this article Ibn Sinān's contribution.
Evolutionary Systems Theory: A Unifying Meta-Theory of Psychological Science
Authors: Badcock Paul B.
Published: February 2012

Psychology is a theoretically heterogeneous discipline seeking a single, cohesive framework to unite the subdisciplines. To address this issue, I propose a hierarchical metatheory of psychological science that synthesizes neo-Darwinian selectionist thinking and dynamic systems theory by organizing evolutionary psychology, evolutionary developmental biology, developmental psychobiology, and the subdisciplines of psychology around four specific, interrelated levels of analysis: functional explanations for evolved, species-typical characteristics; explanations for between-groups differences arising from phylogenetic mechanisms; explanations for individual differences resulting from ontogenetic processes; and mechanistic explanations for real-time phenomena, respectively. Informational exchange between these levels advances their integration and facilitates important innovations, and the nonsubstantive metatheories of general selection and self-organization interpenetrate all four levels to promote consilience. I conclude by discussing the implications of this model for theory and research.
Observational Studies versus Randomized Controlled Trials of Behavioral Interventions in Field Settings
Authors: Staines Graham L. , Cleland Charles M.
Published: February 2012

This article considers research designs that evaluate outcomes of behavioral interventions in field settings. It focuses on differences in efficacy estimates between observational studies (OSs) and randomized controlled trials (RCTs). The article contends that pretreatment motivation and in-treatment compliance both contribute to treatment outcomes. It proposes a 3-variable causal model in which pretreatment motivation produces positive treatment outcomes directly, and also indirectly, via in-treatment compliance. The article challenges the common notion that RCTs represent the gold standard in designs for evaluating the efficacy of behavioral interventions in field settings. The article's causal model predicts that OSs governed by self-assignment and RCTs of the same behavioral interventions both yield biased estimates of efficacy, although these effect-size biases are generally in opposite directions. OS estimates of efficacy are typically too large because of group differences in pretreatment motivation favoring the treated group over the untreated group. RCT efficacy estimates are typically too small because noncompliance in treatment conditions dilutes the impact of field interventions. Taken together, motivation and compliance thus account for the 2 expected efficacy biases: overestimation of effect sizes in OSs and underestimation in RCTs. Accordingly, the causal model predicts that, under most conditions, OSs will generate larger effect sizes than RCTs and thus a higher proportion of significant results. The article examines published outcome evaluations in 3 psychological domains: vocational counseling, precollege academic programs and home-visiting programs. Consistent with the model's directional prediction, studies in all 3 domains document a systematic efficacy difference between OSs and RCTs.
An H-module linear actuator for medical equipment applications
Authors: Liu Xiao , Wu Keyuan , Ye Yunyue , Lu Kaiyuan
Published: February 2012

An H-module linear actuator (HMLA) is proposed in this paper for medical equipment applications. Compared to the existing linear actuators used in medical equipment, the proposed H-module linear actuator has much lower normal force, which makes use of an additional air-suspension system unnecessary. The working principle of the HMLA is illustrated in detail in this paper, and its tangential and normal force characteristics are demonstrated by using finite element analysis (FEA). It is proved that the normal force of the HMLA can be greatly reduced without sacrificing the useful tangential force component.
Semi-implicit integration scheme for Landau–Lifshitz–Gilbert-Slonczewski equation
Authors: Giordano A. , Finocchio G. , Torres L. , Carpentieri M. , Azzerboni B.
Published: February 2012

This paper shows how to implement a semi-implicit algorithm based on the Adams-Bashforth algorithm as a predictor, and a second order Adams-Moulton procedure as a corrector in the Landau–Lifshitz–Gilbert-Slonczewski equation. We compare the results with a Runge-Kutta scheme of the 5th order, while for the standard problem #4 (and, in general, for the LLG equation) the computational speeds are of the same order, and we found better performance when the thermal fluctuations or the spin-polarized currents are taken into account.