bluuebunny/crossref_metadata_2025 huggingface dataset:
Efficacy and Safety of Rituximab in Elderly Patients With Rheumatoid Arthritis Enrolled in a French Society of Rheumatology Registry
Authors: Payet Sarah , Soubrier Martin , Perrodeau Elodie , Bardin Thomas , Cantagrel Alain , Combe Bernard , Dougados Maxime , Flipo René‐Marc , Le Loët Xavier , Shaeverbeke Thierry , Ravaud Philippe , Gottenberg Jacques‐Eric , Mariette Xavier
Published: February 2014

Objective

The aim of this study was to compare the efficacy and safety of rituximab (RTX) as a function of patient age.

Methods

We included all rheumatoid arthritis patients in the AutoImmunity and Rituximab registry with a 2‐year followup.

Results

Of the 1,709 patients, 191 were age ≥75 years, 417 were ages 65–74 years, 907 were ages 50–64 years, and 194 were age <50 years. At baseline, the elderly and very elderly patients presented with longer disease duration, a higher incidence of erythrocyte sedimentation rate and C‐reactive protein level, a lower incidence of previous tumor necrosis factor α (TNFα) therapy, and a smaller number of previously used TNFα agents. Disease activity, rheumatoid factor (RF), or anti–cyclic citrullinated peptide (anti‐CCP) antibodies and corticosteroid therapy were not statistically different among the groups. At 24 months, no significant difference was shown among the groups for RTX discontinuation rates (36.1% if age <50 years, 32.6% if ages 50–64 years, 34.5% if ages 65–74 years, and 32.5% if age >75 years). The reasons for discontinuation (inefficacy, adverse events) were the same in all 4 groups. Infections were more common in the elderly. Patients ages 65–75 years were more likely to be good responders than nonresponders at 1 year of followup than patients age ≥75 years (odds ratio 3.81, 95% confidence interval 1.14–12.79) after adjustment on disease duration, RF/anti‐CCP positivity, corticosteroids, anti‐TNF use, and baseline Disease Activity Score in 28 joints (DAS28). After the sixth month, the decrease in DAS28 score was less marked in the population age >75 years than in the group age <50 years.

Conclusion

The efficacy and safety of RTX is affected by age.
Simple and robust adaptive control
Authors: Barkana Itzhak , Fradkov Alexander L.
Published: February 2014

Most papers of this special issue are extended and revised versions of the papers from the invited sessions dedicated to ‘simple and robust adaptive control’ from the 17th IFAC World Congress (IFAC 2011) and 11th IFAC Workshop on Adaptation and Learning in Control and Signal Processing (ALCOSP 2013). They provide sufficient coverage both for the rigorous mathematical explanation and treatment of the theoretical problems related to stability and performance and the detailed presentation of the specific realistically large application. Copyright © 2014 John Wiley & Sons, Ltd.
Salt, Shake, Fuse—Giant Hybrid Polymer/Lipid Vesicles through Mechanically Activated Fusion
Authors: Henderson Ian M. , Paxton Walter F.
Published: February 2014

Large (200 nm) poly(ethylene oxide)‐b‐poly(butadiene) polymer vesicles fuse into giant (>1 μm) vesicles with mild agitation in dilute aqueous NaCl solutions. This unusual effect is attributed to the salt‐induced contraction of the poly(ethylene oxide) corona, reducing steric resistance between vesicles and, with agitation, increasing the probability of contact between the hydrophobic cores of adjacent membranes. In addition, NaCl and agitation facilitated the creation of giant hybrid vesicles from much smaller homogeneous polymersomes and liposomes. Whereas lipid vesicles do not readily fuse with each other under the same circumstances, they did fuse with polymersomes to produce hybrid polymer/lipid vesicles.
Asymmetric Organocatalytic Direct C(sp2)H/C(sp3)H Oxidative Cross‐Coupling by Chiral Iodine Reagents
Authors: Wu Hua , He Yu‐Ping , Xu Lue , Zhang Dong‐Yang , Gong Liu‐Zhu
Published: February 2014

An asymmetric organocatalytic direct CH/CH oxidative coupling reaction of N1,N3‐diphenylmalonamides has been well established by using chiral organoiodine compounds as catalysts, wherein four CH bonds were stereoselectively functionalized to give structurally diverse spirooxindoles with high levels of enantioselectivity. More importantly, the findings indicated that chiral hypervalent organoiodine reagents can serve as alternative catalysts for the creation of enantioselective functionalization of inactive CH bonds.
Continuous‐Flow Synthesis of Functionalized Phenols by Aerobic Oxidation of Grignard Reagents
Authors: He Zhi , Jamison Timothy F.
Published: February 2014

Phenols are important compounds in chemical industry. An economical and green approach to phenol preparation by the direct oxidation of aryl Grignard reagents using compressed air in continuous gas‐liquid segmented flow systems is described. The process tolerates a broad range of functional groups, including oxidation‐sensitive functionalities such as alkenes, amines, and thioethers. By integrating a benzyne‐mediated in‐line generation of arylmagnesium intermediates with the aerobic oxidation, a facile three‐step, one‐flow process, capable of preparing 2‐functionalized phenols in a modular fashion, is established.
Selective Amplification of CO Bond Hydrogenation on Pt/TiO2: Catalytic Reaction and Sum‐Frequency Generation Vibrational Spectroscopy Studies of Crotonaldehyde Hydrogenation
Authors: Kennedy Griffin , Baker L. Robert , Somorjai Gabor A.
Published: February 2014

The hydrogenation of crotonaldehyde in the presence of supported platinum nanoparticles was used to determine how the interaction between the metal particles and their support can control catalytic performance. Using gas‐phase catalytic reaction studies and in situ sum‐frequency generation vibrational spectroscopy (SFG) to study Pt/TiO2 and Pt/SiO2 catalysts, a unique reaction pathway was identified for Pt/TiO2, which selectively produces alcohol products. The catalytic and spectroscopic data obtained for the Pt/SiO2 catalyst shows that SiO2 has no active role in this reaction. SFG spectra obtained for the Pt/TiO2 catalyst indicate the presence of a crotyl‐oxy surface intermediate. By adsorption through the aldehyde oxygen atom to an O‐vacancy site on the TiO2 surface, the CO bond of crotonaldehyde is activated, by charge transfer, for hydrogenation. This intermediate reacts with spillover H provided by the Pt to produce crotyl alcohol.
Hollow Spheres of Iron Carbide Nanoparticles Encased in Graphitic Layers as Oxygen Reduction Catalysts
Authors: Hu Yang , Jensen Jens Oluf , Zhang Wei , Cleemann Lars N. , Xing Wei , Bjerrum Niels J. , Li Qingfeng
Published: February 2014

Nonprecious metal catalysts for the oxygen reduction reaction are the ultimate materials and the foremost subject for low‐temperature fuel cells. A novel type of catalysts prepared by high‐pressure pyrolysis is reported. The catalyst is featured by hollow spherical morphologies consisting of uniform iron carbide (Fe3C) nanoparticles encased by graphitic layers, with little surface nitrogen or metallic functionalities. In acidic media the outer graphitic layers stabilize the carbide nanoparticles without depriving them of their catalytic activity towards the oxygen reduction reaction (ORR). As a result the catalyst is highly active and stable in both acid and alkaline electrolytes. The synthetic approach, the carbide‐based catalyst, the structure of the catalysts, and the proposed mechanism open new avenues for the development of ORR catalysts.
Acrylonitrile–butadiene rubber functionalization for the toughening modification of recycled poly(ethylene terephthalate)
Authors: Raiisi‐Nia Mohammad Reza , Aref‐Azar Ahmad , Fasihi Mohammad
Published: February 2014

The incorporation of functionalized acrylonitrile–butadiene rubber (NBR) into recycled poly(ethylene terephthalate) (PET) was introduced as an effective route for modifying the properties of PET and as a new method for PET recycling as well. To achieve modified NBR, glycidyl methacrylate (GMA) was grafted onto NBR with optimized reactive mixing, in which the highest grafting degree and lowest gel content were generated. PET/NBR blends with and without GMA functionalization were produced by melt mixing, and the mechanical properties, dynamic mechanical thermal properties, and phase morphologies of the systems were determined and compared. We found that low amounts of peroxide initiator (dicumyl peroxide) and high levels of the GMA monomer in the presence of the styrene comonomer led to the maximum grafting degree and suppressed the competing rubber crosslinking and GMA homopolymerization reactions. The blend compatibility with PET determined from dynamic mechanical thermal analysis spectra and scanning electron microscopy images was greatly improved when the NBR‐grafted GMA was used instead of the neat NBR in the blend recipes. As a result, the rubber phase dispersed in the PET matrix more finely, and the impact strength of the blend advanced very significantly. © 2014 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2014, 131, 40483.
Association of Serum C‐Reactive Protein Levels With Lupus Disease Activity in the Absence of Measurable Interferon‐α and a C‐Reactive Protein Gene Variant
Authors: Enocsson Helena , Sjöwall Christopher , Kastbom Alf , Skogh Thomas , Eloranta Maija‐Leena , Rönnblom Lars , Wetterö Jonas
Published: February 2014

Objective

The type I interferon (IFN) system is important in the pathogenesis of systemic lupus erythematosus (SLE). We previously demonstrated an inhibitory effect of IFNα on interleukin‐6 (IL‐6)–induced C‐reactive protein (CRP) in vitro, hypothetically explaining the poor correlation between disease activity and CRP levels in SLE. This study was undertaken to investigate disease activity, IL‐6 levels, and CRP levels in relation to a CRP gene polymorphism and IFNα.

Methods

Sera from 155 SLE patients and 100 controls were analyzed for CRP. Patients were genotyped for a CRP single‐nucleotide polymorphism (rs1205) associated with low CRP levels. Serum IFNα and IL‐6 levels were quantified by immunoassays. Clinical disease activity was assessed using the SLE Disease Activity Index 2000 (SLEDAI‐2K).

Results

CRP levels were increased in SLE patients compared to controls, but were not associated with SLEDAI‐2K or IL‐6 levels. However, exclusion of patients carrying at least one rs1205 minor allele revealed an association between disease activity and CRP levels (P = 0.005). We found a strong association between disease activity and CRP levels (P < 0.0005) when patients with measurable IFNα levels as well as the minor allele of rs1205 were excluded from the analysis. Similarly, when patients with elevated IFNα levels and/or the rs1205 polymorphism were excluded, IL‐6 levels were associated with CRP levels.

Conclusion

The present study demonstrates that the serum IFNα level as well as the CRP genotype affect the CRP response in SLE patients. Lack of correlation between serum levels of CRP and disease activity could therefore be explained by activation of the type I IFN system and polymorphisms in the CRP gene.
Anatomical evidence for an endocrine activity of the vomeronasal organ in humans
Authors: Wessels Quenton , Hoogland P.V.J.M. , Vorster W.
Published: February 2014

The mammalian vomeronasal organ (VNO) is a well‐adjusted chemosensory structure that facilitates social and reproductive behavior in mammals. The existence, locality, and function of this organ in human adults remain a matter of discussion. Most authors now agree that a neuroreceptive function of the adult human VNO can be excluded due to the absence of both neural receptive cells associated with the VNO in other mammals despite the enigmatic reports on the effects of pheromones on human behavior. Adult cadavers form European (Caucasoid) descent were used in this article and parasagittal dissection of the heads allowed access to the nasal septa, which were grossly examined for the VNO openings. Tissue samples were collected, embedded in gelatin and serially sectioned through cryomicrotomy. Nissl staining was performed as well as immunohistochemically stained with an antibody against calcium‐binding protein. The findings presented here confirm the bilateral presence of the VNO in adult cadavers and demonstrate morphological connections of VNO receptor cells with the underlying capillaries. In addition, possible endocrine activity associated with the epithelium of this chemosensory structure has been demonstrated by the expression of calcium‐binding protein in a part of these receptor cells. Clin. Anat. 27:856–860, 2014. © 2014 Wiley Periodicals, Inc.
Synthesis of glyco‐Fused Bicyclic Compounds; Conformationally Constrained Scaffolds and Useful Polyfunctional Building Blocks
Authors: Cardona Francisco , D'Orazio Giuseppe , Silva Artur M. S. , Nicotra Francesco , La Ferla Barbara
Published: February 2014

We synthesized fused bicyclic polyfunctional compounds containing a highly hydroxylated pyran ring starting from commercially available methyl glucopyranoside and adopting a RCM annulation approach. The versatile α,β‐unsaturated ketone group was introduced on the newly formed ring and, as an example of the potential of these polyfunctionalized building blocks, a tetracyclic compound was synthesized through a Diels–Alder cycloaddition reaction.
Analytic Approximation of Finite‐Maturity Timer Option Prices
Authors: Li Minqiang , Mercurio Fabio
Published: February 2014

We develop an approximation technique for pricing finite‐maturity timer options under Heston‐like stochastic volatility models. By approximating the distributions of the accumulated variance and the random variance budget exceeding time, we obtain analytic expressions for timer option prices under zero correlation. For nonzero correlation, we use a simple linear combination approximation which matches the asymptotic correlation behavior. Numerical analysis using the Heston model shows that the method is fairly accurate, especially when the volatility of variance is small or the maximum maturity is large. © 2014 Wiley Periodicals, Inc. Jrl Fut Mark 35:245–273, 2015
Swallowing, voice, and quality of life after supratracheal laryngectomy: Preliminary long‐term results
Authors: Schindler Antonio , Fantini Marco , Pizzorni Nicole , Crosetti Erika , Mozzanica Francesco , Bertolin Andy , Ottaviani Francesco , Rizzotto Giuseppe , Succo Giovanni
Published: February 2014

Background

The purpose of this study was to report preliminary long‐term outcomes after supratracheal laryngectomy (STL).

Methods

Twenty‐two male patients who underwent STL were involved in this study. Swallowing skills, neoglottis motility, and vibrations were videoendoscopically assessed. Aerodynamic measures, spectrogram analysis, aspiration pneumonia, body weight variations, and voice perceptual assessment were performed. Generic, voice‐related, and swallowing‐related quality of life (QOL) were assessed.

Results

Aspiration was found in 10, 2, and 5 patients, respectively, for liquids, semisolids, and solids. Neoglottis motility was generally preserved, whereas vibration was impaired. Aerodynamic measures showed a poor performance. Perceptual assessment revealed highly dysphonic voices. In only 8 patients, a harmonic structure was visible in the spectrograms. Aspiration pneumonia occurred in 2 patients. Preoperative weight was maintained in 16 patients. Generic, voice‐related, and swallowing‐related QOL revealed satisfied patients.

Conclusion

After STL, swallowing was sufficiently restored and QOL was satisfactory, whereas the voice was severely impaired even if oral communication was well preserved. © 2014 Wiley Periodicals, Inc. Head Neck 37: 557–566, 2015
Combined effects of temperature (level and oscillation) and cadmium concentration on the demography of Brachionus calyciflorus (Rotifera)
Authors: Gama‐Flores José Luis , Huidobro‐Salas María Elena , Sarma S. S. S. , Nandini S.
Published: February 2014

Here, we report on experiments to determine the effects of sub‐lethal concentrations of cadmium (Cd) as CdCl2 (0.05, 0.1, and 0.2 mg L−1) on the life history parameters of Brachionus calyciflorus cultured under two temperature regimes: variable (20–30°C diurnal cycle) and constant (20, 25, or 30°C). Temperature and mode of exposure affected the demographic responses of B. calyciflorus. In general, for B. calyciflorus cultured under constant temperatures and exposed to CdCl2 the life history variables were more adversely affected than those under the variable temperature regime. Age‐specific reproductive output by B. calyciflorus exposed to different temperature regimes under different concentrations of CdCl2 showed a general pattern of increase in offspring production with increasing age of the cohort for the first 10 days and thereafter declined rapidly. Depending on the temperature regime and Cd concentration, average lifespan, gross reproductive rate, net reproductive rate, generation time, and rate of population increase per day varied from 5 to 8 days, 10 to 38 offspring female−1, 5 to 16 offspring female−1, 3 to 5 days, and 0.4 to 1.4 day−1, respectively. In the absence of the heavy metal, average lifespan and gross and net reproductive rates decreased with increase in fixed temperature range, while generation time and the rate of population increase showed no clear trend with constant temperature regimes. The effect of Cd concentration on life history parameters of B. calyciflorus was generally more severe at extreme temperatures (20 or 30°C) as compared to the fluctuating temperature regime. These results have important implications for aquatic toxicology testing protocols.
An examination of the structural link between post‐traumatic stress symptoms and chronic pain in the framework of fear‐avoidance models
Authors: López‐Martínez A.E. , Ramírez‐Maestre C. , Esteve R.
Published: February 2014

Background

The tendency to respond with fear and avoidance can be seen as a shared vulnerability contributing to the development of post‐traumatic stress disorder (PTSD) and chronic pain. Although several studies have examined which specific symptoms of PTSD (re‐experiencing, avoidance, emotional numbing and hyperarousal) are associated with chronic pain, none has considered this association within the framework of fear‐avoidance models.

Methods

Seven hundred fourteen patients with chronic musculoskeletal pain were assessed. Of these, 149 patients were selected for the study based upon the following inclusion criteria: exposure to a traumatic event before the onset of pain (with scores equal to or higher than 8 points on the fear and hopelessness scales of the Stressful Life Event Screening Questionnaire Revised) and scores equal to or higher than 30 on the Davidson Trauma Scale.

Results

Structural equation modelling was used to test the association between PTSD symptoms and pain outcomes (pain intensity and disability) using the mediating variables considered in the fear‐avoidance models. The results show that emotional numbing and hyperarousal symptoms, but neither re‐experiencing nor avoidance, affected pain outcome via anxiety sensitivity (AS), catastrophizing and fear of pain. PTSD symptoms increased the levels of AS, which predisposes to catastrophizing and, in turn, had an effect on the tendency of pain patients to respond with more fear and avoidance.

Conclusions

This study provides empirical support for the potential role of PTSD symptoms in fear‐avoidance models of chronic pain and suggests that AS is a relevant variable in the relationship between both disorders.
The effect of stem material and surface treatment on the torsional stability at the metal–cement interface of upper limb joint replacement systems
Authors: Hosein Yara K. , King Graham J. W. , Dunning Cynthia E.
Published: February 2014

Stem surface treatment and material are two design factors that may affect the onset of implant loosening. For upper limb applications, no known in vitro studies have addressed the role of these two factors on cemented implant stability. Therefore, the purpose of this study was to compare the torsional stability of cemented titanium and cobalt chrome stems with varying surface treatments in vitro. Thirty implant stems of circular cross‐section (Ø = 8mm) were machined from cobalt chrome (n = 15) and titanium (n = 15). For each type, stems were subdivided into three groups for application of clinically relevant surface treatments: smooth, sintered beads, or plasma spray. Stems were potted in bone cement, allowed 24 h to cure, and placed in a materials testing machine. Stems were tested under cyclic torsion (1–30 Nm), using a staircase loading protocol. Failure was defined as either the first rapid increase in stem rotation without resistance, or attaining a maximum torque of 30 Nm. Implant stems with non‐smooth surfaces offered greater resistance to torsion (p < 0.05), with the plasma spray treatment outlasting the beaded and smooth stems (p < 0.05). Titanium offered superior interface strength (p < 0.05) but reduced resistance to motion (p < 0.05) when compared to cobalt chrome. Therefore, these design features should be considered during upper limb implant design. © 2013 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 102B: 1217–1222, 2014.
Design of a reaction field using a linear‐combination‐based isotropic periodic sum method
Authors: Takahashi Kazuaki Z.
Published: February 2014

In our previous study (Takahashi et al., J. Chem. Theory Comput. 2012, 8, 4503), we developed the linear‐combination‐based isotropic periodic sum (LIPS) method. The LIPS method is based on the extended isotropic periodic sum theory that produces a ubiquitous interaction potential function to estimate homogeneous and heterogeneous systems. The LIPS theory also provides the procedure to design a periodic reaction field. To demonstrate this, in the present work, a novel reaction field of the LIPS method was developed. The novel reaction field was labeled LIPS‐SW, because it provides an interaction potential function with a shape that resembles that of the switch function method. To evaluate the ability of the LIPS‐SW method to describe in homogeneous and heterogeneous systems, we carried out molecular dynamics (MD) simulations of bulk water and water–vapor interfacial systems using the LIPS‐SW method. The results of these simulations show that the LIPS‐SW method gives higher accuracy than the conventional interaction potential function of the LIPS method. The accuracy of simulating water–vapor interfacial systems was greatly improved, while that of bulk water systems was maintained using the LIPS‐SW method. We conclude that the LIPS‐SW method shows great potential for high‐accuracy, high‐performance computing to allow large scale MD simulations. © 2014 Wiley Periodicals, Inc.
Helmholtz decomposition of vector fields with mixed boundary conditions and an application to a posteriori finite element error analysis of the Maxwell system
Authors: Creusé Emmanuel , Nicaise Serge , Tang Zuqi
Published: February 2014

This paper is devoted to the derivation of a Helmholtz decomposition of vector fields in the case ofmixed boundary conditions imposed on the boundary of the domain. This particular decomposition allows to obtain a residual a posteriori error estimator for the approximation ofmagnetostatic problems given in the so‐calledA‐formulation, for which the reliability can be established. Numerical tests confirm the obtained theoretical predictions. Copyright © 2014 John Wiley & Sons, Ltd.
CRAPT: an improved version of APT with compensation for variations in JCH
Authors: Burrow Timothy E. , Burns Darcy C. , Krishnamurthy Krish , Reynolds William F.
Published: February 2014

A modified version of the attached proton test (APT) sequence for 13C spectral editing, which we call CRisis‐APT (CRAPT), is developed and tested on representative organic compounds. CRAPT incorporates 13C compensation for refocusing inefficiency with synchronized inversion sweeps (CRISIS) pulses in combination with 1H broadband inversion pulses to give improved compensation for variations in 1JCH along with improved refocusing efficiency. It is shown that CRAPT gives edited 13C spectra with only small losses in sensitivity (between 8% and 15% for strychnine, 1, menthol, 2, cholecalciferol, 3, and isotachysterol, 4), compared with basic 13C spectra obtained on the same compounds. CRAPT also gives significantly better signal/noise than DEPTQ for nonprotonated carbons. Therefore, we conclude that CRAPT is an improvement over APT or DEPTQ or a combination of DEPT135 with a full 13C spectrum for routine 13C spectral editing of organic compounds. Copyright © 2014 John Wiley & Sons, Ltd.
An Exploration of the Impact of Anti‐TNFα Medication on Exercise Behaviour in Patients with Ankylosing Spondylitis
Authors: Stockdale Jennifer , Selfe James , Roddam Hazel
Published: February 2014

Background

Exercise has traditionally been an important part of the treatment of ankylosing spondylitis (AS) in order to maintain spinal mobility. Additionally, anti‐tumour necrosis factor‐alpha (TNFα) medication has been proven highly effective in treating the condition. Over recent years, a few papers have shown the synergistic effect of combining anti‐TNFα medication with rehabilitation. There is minimal evidence on the perceptions of AS patients on how the medication has affected their exercise behaviour. The aim of the present study was to explore the effects of anti‐TNFα medication on exercise behaviour in patients with AS.

Method

A qualitative approach was adopted to provide a holistic understanding of participants’ exercise behaviour while on anti‐TNFα medication. Semi‐structured interviews were undertaken and transcribed verbatim. Data were analysed using thematic network analysis. Ethical approval and informed consent were obtained.

Results

Twenty participants (age range 26–74, disease duration 3–36 years) who had been on the medication for over a year described how their exercise behaviour had improved since being on the medication. They highlighted their motivation and incentives to continue with an exercise programme. The participants had reinstated previous sporting activities, started new ones and regularly undertook physiotherapy exercises.

Conclusion

The present study provides evidence of the long‐term effects of anti‐TNFα medication on the exercise behaviour of AS patients. It shows that AS patients are able to sustain a regular exercise programme over a number of years, provides insight into what motivates them to exercise and reveals the incentives that have influenced their choice of activity. Copyright © 2014 John Wiley & Sons, Ltd.
Exploring the influence of interparticle friction on critical state behaviour using DEM
Authors: Huang Xin , Hanley Kevin J. , O'Sullivan Catherine , Kwok Chung Yee
Published: February 2014

Understanding the extent to which discrete element method (DEM) simulations can capture the critical state characteristics of granular materials is important to legitimize the use of DEM in geomechanics. This paper documents a DEM study that considered the sensitivity of the critical state response characteristics to the coefficient of interparticle friction (μ) using samples with gradings that are representative of a real soil. Most of the features that are typically associated with sand behaviour at the critical state were seen to emerge from the DEM simulation data. An important deviation occurs when high μ values (μ  ≥ 0.5) are used, as has been the case in a number of prior DEM studies. While there is a systematic variation in the critical state behaviour with μ for μ  < 0.5, when μ ≥ 0.5, the behaviour at the critical state seems to be insensitive to further increases in μ. In contrast to observations of conventional soil response, when μ ≥ 0.5, the void ratio at the critical state initially increases with increasing mean effective stress (p′). Analysis of the DEM data and use of simple models of isolated force chains enabled some key observations. When ‘floating’ particles that do not transmit stress are eliminated from the void ratio calculation, the void ratio at the critical state decreases consistently with increasing p′. There is a transition from sliding to rolling behaviour at the contact points as μ increases. Beyond a limiting value of μ, further increases in μ do not increase the buckling resistance of individual strong force chains. Copyright © 2014 John Wiley & Sons, Ltd.
Double‐pulsed diffusional kurtosis imaging
Authors: Jensen Jens H. , Hui Edward S. , Helpern Joseph A.
Published: February 2014

Diffusional kurtosis imaging (DKI) is extended to double‐pulsed‐field‐gradient (d‐PFG) diffusion MRI sequences. This gives a practical approach for acquiring and analyzing d‐PFG data. In particular, the leading d‐PFG effects, beyond what conventional single‐pulsed field gradient (s‐PFG) provides, are interpreted in terms of the kurtosis for a diffusion displacement probability density function (dPDF) in a six‐dimensional (6D) space. The 6D diffusional kurtosis encodes the unique information provided by d‐PFG sequences up to second order in the b‐value. This observation leads to a compact expression for the signal magnitude, and it suggests novel data acquisition and analysis methods. Double‐pulsed DKI (DP‐DKI) is demonstrated for in vivo mouse brain with d‐PFG data obtained at 7 T. Copyright © 2014 John Wiley & Sons, Ltd.
The effect of free health care on polypharmacy: a comparison of propensity score methods and multivariable regression to account for confounding
Authors: Richardson Kathryn , Kenny Rose Anne , Bennett Kathleen
Published: February 2014

Purpose

Differing healthcare access has implications for public health. In Ireland, eligibility for free public health care is means tested. Here, we examine the association between healthcare access and polypharmacy while accounting for underlying socio‐economic and health status differences.

Methods

Self‐reported regular medication use, history of diagnosed health conditions, disability, socio‐demographics, and objective measures of depression and anxiety for adults aged 50–69 years (n = 5796) were ascertained from the population‐representative Irish Longitudinal Study on Ageing. Objective measures of frailty, cognition, hypertension, and body mass index were also assessed for 4241 participants. The associations between free healthcare access and polypharmacy and use of 15 medication classes were estimated using multivariable modified Poisson regression, adjustment for the propensity score, and inverse probability of treatment weighting by the propensity score.

Results

Polypharmacy was reported by 22% and 7% of the 1932 and 3864 participants with and without public healthcare coverage. Public patients had a 21–38% greater risk of polypharmacy depending on the method used to account for confounding. Results were less robust using propensity score weighting. There was evidence that classes of cardiovascular drugs, drugs for acid‐related disorders, and analgesics were used more commonly in public patients. Associations were mostly unaffected after also accounting for objective health measures but were significantly attenuated after accounting for frequency of healthcare visits.

Conclusions

Publically funded health care in Ireland leads to greater medication use in people aged 50–69 years. This may reflect over‐prescribing to public patients or restricted use among those who pay out of pocket. Copyright © 2014 John Wiley & Sons, Ltd.
Increase in breakdown voltage of AlGaN/GaN HEMTs with a high‐k dielectric layer
Authors: Hanawa Hideyuki , Horio Kazushige
Published: February 2014

A two‐dimensional analysis of breakdown characteristics in AlGaN/GaN high‐electron‐mobility transistors (HEMTs) is performed by considering a deep donor and a deep acceptor in a buffer layer. The dependence of an off‐state breakdown voltage on the relative permittivity of the passivation layer ϵr is studied. It is shown that as ϵr increases, the off‐state breakdown voltage increases. This is because the electric field at the drain edge of the gate is weakened as ϵr increases. This occurs because in the insulator the applied voltage tends to drop uniformly in general, and hence when the insulator is attached to the semiconductor, the voltage drop along the semiconductor becomes smoother at the drain edge of the gate if ϵr of the insulator is higher and the effect of the insulator becomes more significant. It is concluded that AlGaN/GaN HEMTs with a high‐k passivation layer should have high breakdown voltages.
Anisotropic crystalline morphology of epitaxial thick AlN films grown on triangular‐striped AlN/sapphire template
Authors: Arauchi Takuji , Takeuchi Shotaro , Nakamura Kunihiko , Khan Dinh Thanh , Nakamura Yoshiaki , Miyake Hideto , Hiramatsu Kazumasa , Sakai Akira
Published: February 2014

We have investigated crystalline morphology such as wafer curvature, mosaicity, and lattice tilting of an AlN film grown on a triangular‐striped AlN/α‐Al2O3 template by X‐ray rocking curve (XRC) and reciprocal space map (RSM) measurements. The result of XRC for the AlN (0002) plane showed the difference of the value in the wafer curvature between the [11–20] and [1–100] directions. This indicates the anisotropic strain relaxation preferentially along [11–20] direction due to the triangular‐striped structure and the voids in the AlN film. From the results of asymmetric RSMs for AlN 11–24 and 1–104 diffractions, the broadening of the reciprocal lattice spots in elliptical shape was observed. These results reflect anisotropic crystalline morphology in the AlN film. The elliptical diffraction spot for AlN 11–24 predominantly indicates the lattice tilting fluctuation around the [1–100] axes while that for AlN 1–104 indicates the lattice spacing fluctuation. Anisotropic crystalline morphology in the AlN film grown on the triangular‐striped template has been clarified in combination with XRC and asymmetric RSMs.
Relaxor ferroelectrics: Cluster glass ground state via random fields and random bonds
Authors: Kleemann Wolfgang
Published: February 2014

Quenched random fields (RFs) are well‐known to be a basic driving force of the relaxor behavior in disordered ferroelectrics containing either random charges as in PbMg1/3Nb2/3O3 or random cation vacancies as in SrxBa1−xNb2O6. They give rise to the formation of polar nanoregions in the paraelectric regime, which freeze into a nanodomain state at low temperatures thus precluding the ferroelectric phase transition. On the other hand, isovalent relaxors like bond‐disordered BaTi1−xZrxO3 prevalently experience random bonds (RBs), which are responsible for glassy features such as polydispersivity and non‐ergodic aging and rejuvenation processes. Inspection shows, however, that all of the above characteristics apply generally to relaxor systems albeit with different weight. Subsequent formation of ferroic nanoregions via RFs followed by mesoscopic cluster glassy freezing via RBs upon cooling are universal signatures.
Theoretical study of Pu and Am tetracarbide molecules
Authors: Pogány Peter , Kovács Attila , Konings Rudy J. M.
Published: February 2014

The electronic structure and ground‐state molecular properties of Pu and Am tetracarbides have been investigated by relativistic multireference calculations using CASSCF/CASPT2 theory as well as by density functional theory in conjunction with relativistic pseudopotentials. The CASSCF/CASPT2 treatment has been extended by spin–orbit coupling effects for selected species using the CAS state‐interaction method. The five atoms can form various structural isomers, from which 12 ones have been identified in our study. The electronic ground state in both molecules corresponds to a planar fan‐type structure of C2v symmetry, in which the actinide atom is connected to a bent C4 moiety. The other structures are much higher in energy, the ones computed in this study appear between 250 and 1050 kJ/mol. The bonding characteristics in the most relevant structures have been analyzed on the basis of the valence molecular orbitals and natural bond orbital analysis. The most stable structures have been characterized by their spectroscopic (vibrational and electron) properties. © 2014 Wiley Periodicals, Inc.
A density functional study on the pKa of small polyprotic molecules
Authors: Baba Takeshi , Matsui Toru , Kamiya Katsumasa , Nakano Masayoshi , Shigeta Yasuteru
Published: February 2014

The pKa values of several biologically important small molecules in aqueous solution, such as salicylic acid, histamine, and dopamine, were determined by density functional theory combined with the polarizable continuum model, which has been proposed for predicting pKa values of nucleic acids and proteins. These molecules have plural protonation sites and the inherent pKa determines which protons exist at a specific pH. Taking into account the ensemble average, and that the order of the deprotonation steps is specific among several possible pathways, it emerged that the calculated pKa values mostly reproduced the experimental ones within an error of ± 1.0 pKa units. © 2014 Wiley Periodicals, Inc.
Facile Smiles‐type rearrangement in radical cations of N‐acyl arylsulfonamides and analogs
Authors: Irikura Karl K. , Todua Nino G.
Published: February 2014

RATIONALE

N‐Alkylation of sulfonylbenzamides was reported recently to cause a dramatic and surprising change in electron ionization mass spectrometry (EIMS), leading to a closed‐shell base peak. Only an incomplete, speculative mechanism was available at that time. The fragmentation mechanism is determined in the present work and set in the context of related compounds.

METHODS

Candidate reaction mechanisms were evaluated theoretically using modest density‐functional calculations. The fragmentation mechanism with the lowest barriers was identified and one of its implications tested successfully by experimental 18O‐isotopic substitution.

RESULTS

The amide oxygen atom attacks the arylsulfonyl group at the ipso position (Smiles‐type rearrangement), displacing a molecule of SO2. The resulting carboximidate radical cation has a weak C–O bond that breaks easily. The incipient aryloxyl radical abstracts a proton from the amide nitrogen to form the dominant product ion, but if the molecule is N‐alkylated this cannot occur. Instead, the neutral aryloxyl radical is lost and a closed‐shell, N‐alkyl nitrilium ion is the major product.

CONCLUSIONS

The Smiles‐type ion fragmentation mechanism is facile for the title compounds, despite the necessity for carbonyl oxygen to serve as a nucleophile. This rearrangement probably occurs in many of the mass spectra reported for structurally similar compounds, in which the nucleophile may be a thione, arylthio, imine, methylene, or methine moiety. Published in 2014. This article is a U.S. Government work and is in the public domain in the USA.
High‐gain observers in nonlinear feedback control
Authors: Khalil Hassan K. , Praly Laurent
Published: February 2014

High‐gain observers have proved to be an effective tool in the estimation and control of nonlinear systems. This special issue introduces the basic ideas of high‐gain observers through a tutorial paper, presents new theoretical advances in multi‐output and hybrid systems, and demonstrates applications in electronic, mechanical, and chemical systems. Copyright © 2014 John Wiley & Sons, Ltd.
Synthesis of Multi‐Fullerenes Encapsulated Palladium Nanocage, and Its Application in Electrochemiluminescence Immunosensors for the Detection of Streptococcus suis Serotype 2
Authors: Wang Haijun , Bai Lijuan , Chai Yaqin , Yuan Ruo
Published: February 2014

A novel functionalized material is synthesized using surface‐decorated fullerene (C60) to encapsulate hollow and porous palladium nanocages (PdNCs), and is applied to fabricate an electrochemiluminescence (ECL) immunosensor for the detection of Streptococcus suis Serotype 2 (SS2). PdNCs with hollow interiors and porous walls are prepared using a galvanic replacement reaction between silver nanocubes and metal precursor salts. Then, C60 reacts with l‐cysteine (l‐Cys) to form l‐Cys functionalized C60 (C60‐l‐Cys), which has a better biocompatibility, conductivity, and hydrophilicity compared to C60 and possesses abundant –SH groups on the surface. Because of the special interaction between –SH and PdNCs, the obtained C60‐l‐Cys is adsorbed around the PdNCs to form an interesting structure with multiple spheres encapsulating the cage. The resultant functionalized material (C60‐L‐Cys‐PdNCs) has a high specific surface area, good electrocatalytic ability, and efficient photocatalytic activity, and is used to construct an ECL immunosensor for the detection of SS2. The ECL signal amplified strategy is performed by using the novel coreactant (C60‐l‐Cys) and in situ generation of O2 thus creating the S2O82−‐O2 ECL system. As a result, a wide linear detection range of 0.1 pg mL−1 to 100 ng mL−1 is acquired with a relatively low detection limit of 33.3 fg mL−1.
Exploiting cell metabolism for biocatalytic whole-cell transamination by recombinant Saccharomyces cerevisiae
Authors: Weber Nora , Gorwa-Grauslund Marie , Carlquist Magnus
Published: February 2014

The potential of Saccharomyces cerevisiae for biocatalytic whole-cell transamination was investigated using the kinetic resolution of racemic 1-phenylethylamine (1-PEA) to (R)-1-PEA as a model reaction. As native yeast do not possess any ω-transaminase activity for the reaction, a recombinant yeast biocatalyst was constructed by overexpressing the gene coding for vanillin aminotransferase from Capsicum chinense. The yeast-based biocatalyst could use glucose as the sole co-substrate for the supply of amine acceptor via cell metabolism. In addition, the biocatalyst was functional without addition of the co-factor pyridoxal-5′-phosphate (PLP), which can be explained by a high inherent cellular capacity to sustain PLP-dependent reactions in living cells. In contrast, external PLP supplementation was required when cell viability was low, as it was the case when using pyruvate as a co-substrate. Overall, the results indicate a potential for engineered S. cerevisiae as a biocatalyst for whole-cell transamination and with glucose as the only co-substrate for the supply of amine acceptor and PLP.
Heat Treatment and Chemical Composition of Fatty Acids and Rosin Acids Mixtures: Effects on Their Thermal Properties and Morphology
Authors: Mäki‐Arvela Päivi , Mikkola Mika , Hemming Jarl , Eränen Kari , Willför Stefan , Murzin Dmitry Yu.
Published: February 2014

Mixtures of fatty acids and rosin acids are industrially important products utilized as a raw material for several purposes. Their thermal properties, especially cold stability and crystallization behavior is also important. Several fatty acid and rosin acid mixtures both from industrial products and from commercially available fatty and rosin acids were prepared and treated for 30 min at 80 °C under an inert atmosphere. Thereafter, the mixture was cooled to the desired temperature. Determination of the cloud point, chemical analysis of liquid and solid phase, thermal analysis by differential scanning calorimetry as well as morphology analysis by scanning electron microscopy were performed. The results revealed that crystallization was more rapid when it occurred at 10 °C compared to 25 °C. The crystal sizes increased with decreasing the crystallization temperature. Furthermore, crystals were of irregular shape and agglomerated when rapid cooling of the mixture occurred. Chemical analysis revealed that liquid phase was enriched with stearic acid, whereas crystals contained large amounts of abietic, dehydroabietic and linoleic acids. The cloud point of the mixtures increased with increasing amount of stearic and rosin acids. Dehydroabietic acid addition improved the cold stability of the synthetic fatty acid–rosin acids mixture.
Properties and Stability of Hazelnut Oil Organogels with Beeswax and Monoglyceride
Authors: Yılmaz Emin , Öğütcü Mustafa
Published: February 2014

The objectives of this study were to produce and characterize hazelnut oil (HO) organogels with beeswax (BW) and monoglyceride (MG) organogelators. Oil binding capacities of most samples were over 99 %. As the organogelator level increased, crystal formation time decreased, but solid fat content (SFC %) was enhanced. Although the highest SFC was 8.52 % among the organogel samples, it was 30.35 % in the commercial shortening (CS) at 20 °C. The peak melting temperature of CS was 41.86 °C, and almost all organogels had very close values to it. Melting enthalpies of the samples ranged from 0.48 to 13.40 J/g. Firmness and stickiness values of all samples were measured each month during 90 days of storage. There was no important change during storage. The organogels were texturally very stable, and were very homogenous and smooth in structure. Polarized light microscopy pictures revealed needle‐like crystals for BW and rosette‐like aggregates for MG organogels. The X‐ray diffraction measurements of the crystals also showed the difference of the two types. There would be some hydrogen bonding in only MG organogels as predicted from the infrared spectra. The organogels were very stable against oxidation during storage. HO organogels can be used as shortening or margarine‐like fat stock.
42‐ and 63‐bp anti‐MDR1‐siRNAs bearing 2′‐OMe modifications in nuclease‐sensitive sites induce specific and potent gene silencing
Authors: Gvozdeva Olga V. , Dovydenko IIya S. , Venyaminova Alya G. , Zenkova Marina A. , Vlassov Valentin V. , Chernolovskaya Elena L.
Published: February 2014

DsRNAs longer than 30 bp induce interferon response and global changes in gene expression profile in mammalians. 21 bp siRNA and 25/27 bp dsiRNA acting via RNA interference mechanism are used for specific gene silencing in this class of organisms. We designed selectively 2′‐O‐methyl‐modified 42 and 63 bp anti‐MDR1‐siRNAs that silence the expression of P‐glycoprotein and restore the sensitivity of drug‐resistant cancer cells to cytostatic more efficiently than canonical 21 bp siRNAs. We also show that they act in a Dicer‐independent mode and are devoid of immunostimulating properties. Our findings suggest that 42 and 63 bp siRNAs could be used as potential therapeutics.
Impact of dietary fatty acids on metabolic activity and host intestinal microbiota composition in C57BL/6J mice
Authors: Patterson Elaine , O' Doherty Robert M. , Murphy Eileen F. , Wall Rebecca , O' Sullivan Orla , Nilaweera Kanishka , Fitzgerald Gerald F. , Cotter Paul D. , Ross R. Paul , Stanton Catherine
Published: February 2014

Different dietary fat and energy subtypes have an impact on both the metabolic health and the intestinal microbiota population of the host. The present study assessed the impact of dietary fat quality, with a focus on dietary fatty acid compositions of varying saturation, on the metabolic health status and the intestinal microbiota composition of the host. C57BL/6J mice (n9–10 mice per group) were fed high-fat (HF) diets containing either (1) palm oil, (2) olive oil, (3) safflower oil or (4) flaxseed/fish oil for 16 weeks and compared with mice fed low-fat (LF) diets supplemented with either high maize starch or high sucrose. Tissue fatty acid compositions were assessed by GLC, and the impact of the diet on host intestinal microbiota populations was investigated using high-throughput 16S rRNA sequencing. Compositional sequencing analysis revealed that dietary palm oil supplementation resulted in significantly lower populations of Bacteroidetes at the phylum level compared with dietary olive oil supplementation (P< 0·05). Dietary supplementation with olive oil was associated with an increase in the population of the familyBacteroidaceaecompared with dietary supplementation of palm oil, flaxseed/fish oil and high sucrose (P< 0·05). Ingestion of the HF-flaxseed/fish oil diet for 16 weeks led to significantly increased tissue concentrations of EPA, docosapentaenoic acid and DHA compared with ingestion of all the other diets (P< 0·05); furthermore, the diet significantly increased the intestinal population ofBifidobacteriumat the genus level compared with the LF-high-maize starch diet (P< 0·05). These data indicate that both the quantity and quality of fat have an impact on host physiology with further downstream alterations to the intestinal microbiota population, with a HF diet supplemented with flaxseed/fish oil positively shaping the host microbial ecosystem.