bluuebunny/crossref_metadata_2025 huggingface dataset:
Structure determination of two new trichothecenes from a halotolerant fungus Myrothecium sp. GS‐17 by NMR spectroscopy
Authors: Zhang Song‐Ya , Li Zhan‐Lin , Guan Li‐Ping , Wu Xin , Pan Hua‐Qi , Bai Jiao , Hua Hui‐Ming
Published: July 2012

Two new trichothecenes, named 8α‐hydroxyroridin H and myrothecin A, along with six known compounds, 8α‐acetoxy roridin H, isororidin K, verrucarin A, verrucarin J, verrucarin L and 8α‐acetoxy verrucarin L, were isolated from the fermentation broth of a halotolerant fungus Myrothecium sp. GS‐17, which was separated from the soil sample of a salina. Structure elucidation and NMR signal assignments were achieved on the basis of spectroscopy. In addition, compounds 1 and 2 were active against plant pathogenic fungi Rhizoctonia solani and Fusarium oxysporum. Copyright © 2012 John Wiley & Sons, Ltd.
The Effectiveness of Hydrotherapy in the Management of Rheumatoid Arthritis: A Systematic Review
Authors: Al‐Qubaeissy Khamis Y. , Fatoye Francis A. , Goodwin Peter C. , Yohannes Abebaw M.
Published: July 2012

Background

Hydrotherapy is frequently indicated for the rehabilitation of patients with rheumatoid arthritis (RA); nevertheless, there has been inadequate appraisal of its effectiveness. The potential benefits of hydrotherapy for patients with RA are to improve and/or maintain functional ability and quality of life.

Objectives

The aim of this systematic review was to evaluate the effectiveness of hydrotherapy in the management of patients with RA.

Method

AMED, CINAHL, EMBASE, MEDLINE, PubMed, Science Direct and Web of Science were searched between 1988 and May 2011. Keywords used were rheumatoid arthritis, hydrotherapy, aquatic physiotherapy, aqua therapy and water therapy. Searches were supplemented with hand searches of references of selected articles. Randomized controlled trials were assessed for their methodological quality using the Physiotherapy Evidence Database (PEDro) scale. This scale ranks the methodological quality of a study scoring 7 out of 10 as ‘high quality’, 5–6 as ‘moderate quality’ and less than 4 as ‘poor quality’.

Results

Initially, 197 studies were identified. Six studies met the inclusion criteria for further analysis. The average methodological quality for all studies was 6.8 using the PEDro scale. Most of the studies reported favourable outcomes for a hydrotherapy intervention compared with no treatment or other interventions for patients with RA. Improvement was particularly noted in reducing pain, joint tenderness, mood and tension symptoms, and increasing grip strength and patient satisfaction with hydrotherapy treatment in the short term.

Conclusions

There is some evidence to suggest that hydrotherapy has a positive role in reducing pain and improving the health status of patients with RA compared with no or other interventions in the short term. However, the long‐term benefit is unknown. Further studies are needed. Copyright © 2012 John Wiley & Sons, Ltd.
Nonlinear homogenization approach to the friction coefficient of a quartz‐clay fault gouge
Authors: Barthélémy Jean‐François , Souque Christine , Daniel Jean‐Marc
Published: July 2012

This study aims at building a theoretical framework allowing for estimation of the macroscopic friction coefficient of a mixed quartz/clay fault gouge from the description of the microstructure and from relevant properties at the lower scale. The effect of clay content is particularly highlighted through two opposite morphology cases. The first one corresponds to a grain framework‐supported microstructure with a predominant content of quartz grains forming a connected structure and some clay filling the intergranular space. The second considered morphology corresponds to a clay matrix‐supported microstructure in which quartz grains are embedded. The friction coefficient of the gouge is derived with respect to the clay content for both morphologies because of theoretical homogenization techniques. The models prove to be in good agreement with experimental results from the literature. Copyright © 2012 John Wiley & Sons, Ltd.
Treatment response monitoring in patients with gastrointestinal stromal tumor using diffusion‐weighted imaging: preliminary results in comparison with positron emission tomography/computed tomography
Authors: Gong Nan‐Jie , Wong Chun‐Sing , Chu Yiu‐Ching , Gu Jing
Published: July 2012

We compared the parameters derived from diffusion‐weighted imaging (DWI) and positron emission tomography/computed tomography (PET/CT) for treatment response evaluation and response prediction in patients with gastrointestinal stromal tumor (GIST). Seven patients with histologically proven metastatic disease were enrolled. DWI and PET/CT data were collected from all patients at diagnosis and from six at follow‐up. All 37 lesions were identifiable in DWI with a sensitivity of 100%. To achieve higher accuracy, we used the apparent diffusion coefficient (ADC) of liver and background noise as thresholds for the measurement of the ADCs of lesions. Significant inverse correlations were found between ADCmean_thr (ADCmean with thresholds) and SUVmean (mean standardized uptake value) (R2 = 0.523, p < 0.001 at diagnosis, and R2 = 0.916, p < 0.001 at follow‐up), between ADCmean_thr and SUVmax (maximum SUV) (R2 = 0.529, p < 0.001 at diagnosis, and R2 = 0.761, p < 0.001 at follow‐up), between ΔADCmean_thr (percentage change in ADCmean_thr) and ΔSUVmean (percentage change in SUVmean) (R2 = 0.384, p < 0.001), and between ΔADCmean_thr and ΔSUVmax (percentage change in SUVmax) (R2 = 0.500, p < 0.001). In lesion‐based analysis, pre‐treatment ADCmean_thr outperformed SUVmean and SUVmax in treatment response prediction, with an area under the receiver operating characteristic curve of 0.706. These results show that DWI can provide a quantitative assessment comparable with PET/CT in GIST lesion characterization, treatment response evaluation and response prediction. Copyright © 2012 John Wiley & Sons, Ltd.
An augmented Lagrangian technique combined with a mortar algorithm for modelling mechanical contact problems
Authors: Cavalieri F.J. , Cardona A.
Published: July 2012

A finite element formulation for three dimensional (3D) contact mechanics using a mortar algorithm combined with a mixed penalty–duality formulation from an augmented Lagrangian approach is presented. In this method, no penalty parameter is introduced for the regularisation of the contact problem. The contact approach, based on the mortar method, gives a smooth representation of the contact forces across the bodies interface, and can be used in arbitrarily curved 3D configurations. The projection surface used for integrating the equations is built using a local Cartesian basis defined in each contact element. A unit normal to the contact surface is defined locally at each element, simplifying the implementation and linearisation of the equations. The displayed examples show that the algorithm verifies the contact patch tests exactly, and is applicable to large displacements problems with large sliding motions.Copyright © 2012 John Wiley & Sons, Ltd.
Nonculture‐based identification of bacteria in milk by protein fingerprinting
Authors: Barreiro Juliana Regina , Braga Patricia Aparecida Campos , Ferreira Christina Ramires , Kostrzewa Markus , Maier Thomas , Wegemann Beatrix , Böettcher Viktoria , Eberlin Marcos N. , dos Santos Marcos Veiga
Published: July 2012

Traditional methods for bacterial identification include Gram staining, culturing, and biochemical assays for phenotypic characterization of the causative organism. These methods can be time‐consuming because they require in vitro cultivation of the microorganisms. Recently, however, it has become possible to obtain chemical profiles for lipids, peptides, and proteins that are present in an intact organism, particularly now that new developments have been made for the efficient ionization of biomolecules. MS has therefore become the state‐of‐the‐art technology for microorganism identification in microbiological clinical diagnosis. Here, we introduce an innovative sample preparation method for nonculture‐based identification of bacteria in milk. The technique detects characteristic profiles of intact proteins (mostly ribosomal) with the recently introduced MALDI SepsityperTM Kit followed by MALDI‐MS. In combination with a dedicated bioinformatics software tool for databank matching, the method allows for almost real‐time and reliable genus and species identification. We demonstrate the sensitivity of this protocol by experimentally contaminating pasteurized and homogenized whole milk samples with bacterial loads of 103–108 colony‐forming units (cfu) of laboratory strains of Escherichia coli, Enterococcus faecalis, and Staphylococcus aureus. For milk samples contaminated with a lower bacterial load (104 cfu mL−1), bacterial identification could be performed after initial incubation at 37°C for 4 h. The sensitivity of the method may be influenced by the bacterial species and count, and therefore, it must be optimized for the specific application. The proposed use of protein markers for nonculture‐based bacterial identification allows for high‐throughput detection of pathogens present in milk samples. This method could therefore be useful in the veterinary practice and in the dairy industry, such as for the diagnosis of subclinical mastitis and for the sanitary monitoring of raw and processed milk products.
Bulk and shear rheology of a symmetric three‐arm star polystyrene
Authors: Guo Jiaxi , Grassia Luigi , Simon Sindee L.
Published: July 2012

The bulk and shear rheological properties of a symmetric three‐arm star polystyrene were measured using a self‐built pressurizable dilatometer and a commercial rheometer, respectively. The bulk properties investigated include the pressure–volume–temperature behavior, the pressure‐dependent glass transition temperature (Tg), and the viscoelastic bulk modulus and Poisson's ratio. Comparison with data for a linear polystyrene indicates that the star behaves similarly but with slightly higher Tgs at elevated pressures and slightly higher limiting bulk moduli in glass and rubbery states. The Poisson's ratio shows a minimum at short times similar to what is observed for the linear chain. The horizontal shift factors above Tg obtained from reducing the bulk and shear viscoelastic responses are found to have similar temperature dependence when plotted using T −
Tg scaling; in addition, the shift factors also exhibit a similar temperature dependence to linear polystyrene. The retardation spectra for the bulk and shear responses are compared and show that the long time molecular mechanisms available to the shear response are unavailable to the bulk. At short times, the two spectra have similar slopes, but the short‐time retardation spectrum for the shear response is significantly higher than that for the bulk, a finding that is, as yet, unexplained. © 2012 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys, 2012
Walking, bicycling, and sports in postmenopausal breast cancer survivors—results from a German patient cohort study
Authors: Bock Christina , Schmidt Martina E. , Vrieling Alina , Chang‐Claude Jenny , Steindorf Karen
Published: July 2012

Objectives

Physical activity (PA) is increasingly discussed as a means to achieve both physical and psychological benefits for breast cancer patients and survivors. However, little is known about activity‐specific PA behavior following diagnosis. Our objectives were to describe sports and active transportation in the course of breast cancer and to identify factors associated with these activities.

Methods

We used data from a German cohort study including 1067 postmenopausal breast cancer survivors aged 50–75 years. Data were collected about walking and bicycling for transportation purposes and sports before diagnosis, during therapy, and 1 year after surgery. Associations between these activities and clinical, behavioral, and social characteristics were analyzed with logistic regression.

Results

The proportions of physically active women decreased significantly during therapy compared with before diagnosis (walking: 75.1% vs. 89.7%; bicycling: 19.3% vs. 56.5%; sports: 14.8% vs. 64.5%; all p < 0.001). Calisthenics, swimming, and walking for exercise were the most frequent types of sport. Chemotherapy/radiotherapy was negatively associated with sports (odds ratio [OR]: 0.35 [0.17–0.73]) but positively associated with walking during therapy (OR: 2.08 [1.04–4.15]). Although sociodemographic factors showed weak associations with PA, participation in rehabilitation increased the likelihood for bicycling (OR: 1.48 [1.06–2.09]) and sports (OR: 1.88 [1.38–2.58]) 1 year after surgery.

Conclusions

The majority of women stopped exercising and bicycling during breast cancer therapy. Interventions promoting in particular moderate activities after breast cancer diagnosis are required for this population. Increasing participation in rehabilitation might help to increase the proportion of women who bicycle and engage in sports after breast cancer diagnosis. Copyright © 2012 John Wiley & Sons, Ltd.
Method for sampling tissue for research which preserves pathological data in radical prostatectomy
Authors: Warren Anne Y. , Whitaker Hayley C. , Haynes Beverley , Sangan Trogon , McDuffus Leigh‐Anne , Kay Jonathan D. , Neal David E.
Published: July 2012

BACKGROUND

The diagnosis and treatment of prostate cancer is a challenging global healthcare issue requiring significant molecular research. Such research frequently utilizes fresh frozen human tissue which needs to be obtained in a manner acceptable to the pathologist which does not compromise tumor diagnosis or staging.

METHODS

Radical prostatectomy specimens were handled in a standardized method before being sliced fresh. Leaving the margins intact, multiple cylindrical cores were removed using a large skin punch and the sites were marked on a prostate map. The cylindrical cores were placed onto individual, pre‐numbered foil squares and snap frozen in liquid nitrogen. Prostate maps were aligned with formalin‐fixed paraffin embedded hematoxylin and eosin stained sections of the sampled slice to select tumor regions. Frozen tumor tissue cylinders were processed taking one section for hematoxylin and eosin staining, 6 µm × 50 µm sections for molecular studies and a further section for hematoxylin and eosin staining. This was performed for the length of the cylinder.

RESULTS

A total of 150 prostates have been removed and sliced using this technique. Pathological assessment remained uncompromised. Using the sequential hematoxylin and eosin stained frozen sections, cellularity could be monitored closely in tissues processed for research. The yield of RNA and DNA extracted was high (tumor mean 2.4 µg (RNA) and 12.7 ng per 300 µm tissue) and of high quality (mean tumor RIN 5.9).

CONCLUSIONS

This novel, rapid sampling and processing method provides high quality tissue for research without compromising pathology. Prostate 73: 194–202, 2013. © 2012 Wiley Periodicals, Inc.
Making the case: Married versus Separate models of alphaherpes virus anterograde transport in axons
Authors: Kratchmarov R. , Taylor M. P. , Enquist L. W.
Published: July 2012

Alphaherpesvirus virions infect neurons and are transported in axons for long distance spread within the host nervous system. The assembly state of newly made herpesvirus particles during anterograde transport in axons is an essential question in alphaherpesvirus biology. The structure of the particle has remained both elusive and controversial for the past two decades, with conflicting evidence from EM, immunofluorescence, and live cell imaging studies. Two opposing models have been proposed—the Married and Separate Models. Under the Married Model, infectious virions are assembled in the neuronal cell body before sorting into axons and then traffic inside a transport vesicle. Conversely, the Separate Model postulates that vesicles containing viral membrane proteins are sorted into axons independent of capsids, with final assembly of mature virions occurring at a distant egress site. Recently, a complementary series of studies employing high‐resolution EM and live cell fluorescence microscopy have provided evidence consistent with the Married Model, whereas other studies offer evidence supporting the Separate Model. In this review, we compare and discuss the published data and attempt to reconcile divergent findings and interpretations as they relate to these models. Copyright © 2012 John Wiley & Sons, Ltd.
Self‐consistent isotopic comparative method used to determine dependence of secondary‐ion yields on oxygen concentration in Si–O system up to 33 at%
Authors: Dupuy J. C. , Prudon G. , Dubois C. , Kögler R. , Akhmadaliev S. , Perrat‐Mabilon A.
Published: July 2012

With the isotopic comparative method (ICM), we determined the ion yields of B+, O+, Si+, B−, O−, and Si− versus oxygen concentration in silicon under Ar+ bombardment. By multi‐energy implantation, we obtained samples containing a near‐uniform low concentration of 18O, which we then implanted with a high dose of 16O. The ICM allows us to determine the oxygen concentration profile as a function of substrate depth during analysis by secondary‐ion mass spectrometry, following which the ion yield is measured as a function of oxygen concentration from 0 to 33 at.%. The results show that, whatever the charge of secondary ions, all relative ion yields are enhanced with increasing of oxygen concentration. Very strong matrix effects due to oxygen are found for B+ (>100), whereas moderate or slight matrix effects are found for Si+ and O− (>10) and for Si−, B−, and O+ (<4). Whereas the relative ion yields of B+ and Si+ differ (as a function of oxygen concentration), the relative ion yields of B− and Si− are identical. The relative ionization probability versus oxygen concentration for Si+ agrees very well with the results of William's group. Copyright © 2012 John Wiley & Sons, Ltd.
A method for the early health technology assessment of novel biomarker measurement in primary prevention programs
Authors: Postmus Douwe , de Graaf Gimon , Hillege Hans L. , Steyerberg Ewout W. , Buskens Erik
Published: July 2012

Many promising biomarkers for stratifying individuals at risk of developing a chronic disease or subsequent complications have been identified. Research into the potential cost‐effectiveness of applying these biomarkers in actual clinical settings has however been lacking. Investors and analysts may improve their venture decision making should they have indicative estimates of the potential costs and effects associated with a new biomarker technology already at the early stages of its development. To assist in obtaining such estimates, this paper presents a general method for the early health technology assessment of a novel biomarker technology. The setting considered is that of primary prevention programs where initial screening to select high‐risk individuals eligible for a subsequent intervention occurs, for example, prevention of type 2 diabetes. The method is based on quantifying the health outcomes and downstream healthcare consumption of all individuals who get reclassified as a result of moving from a screening variant based on traditional risk factors to a screening variant based on traditional risk factors plus a novel biomarker. As these individuals form well‐defined subpopulations, a combination of disease progression modeling and sensitivity analysis can be used to perform an initial assessment of the maximum increase in screening cost for which the use of the new biomarker technology is still likely to be cost effective. Copyright © 2012 John Wiley & Sons, Ltd.
Sensitivity of the discrete‐time Kaplan–Meier estimate to nonignorable censoring: Application in a clinical trial
Authors: Liu Tao , Heitjan Daniel F.
Published: July 2012

Untestable assumptions about the association between survival and censoring times can affect the validity of estimates of the survival distribution including the Kaplan–Meier (KM) nonparametric maximum likelihood estimate (MLE). This paper explores the sensitivity of the KM curve to nonignorable censoring by extending the index of local sensitivity to nonignorability (ISNI; Troxelet al.,Statistica Sinica,14, 1221–1237, 2004; Zhang and Heitjan,Biometrics,62, 1260–1268, 2006) to the case of a nonparametric survival model. The method involves, first, specifying a coarse‐data selection model to describe the association between the failure and censoring processes and then evaluating the slope of the nonparametric survival MLE ordinate with respect to a nonignorability parameter in the neighborhood of the ignorable model. We define the nonparametric MLE of the survival curve for a fixed value of the nonignorability parameter and show in a simulation that ISNI analysis effectively captures local sensitivity to nonignorability. The method measures sensitivity in the sense of identifying functionals of the nonparametric MLE that nonignorability, if present, can affect substantially. We demonstrate the method with an application to a trial comparing mechanical assistance to optimal medical management in the treatment of end‐stage heart failure. Copyright © 2012 John Wiley & Sons, Ltd.
A flexible spatial scan statistic with a restricted likelihood ratio for detecting disease clusters
Authors: Tango Toshiro , Takahashi Kunihiko
Published: July 2012

Spatial scan statistics are widely used tools for detection of disease clusters. Especially, the circular spatial scan statistic proposed by Kulldorff (1997) has been utilized in a wide variety of epidemiological studies and disease surveillance. However, as it cannot detect noncircular, irregularly shaped clusters, many authors have proposed different spatial scan statistics, including the elliptic version of Kulldorff's scan statistic. The flexible spatial scan statistic proposed by Tango and Takahashi (2005) has also been used for detecting irregularly shaped clusters. However, this method sets a feasible limitation of a maximum of 30 nearest neighbors for searching candidate clusters because of heavy computational load. In this paper, we show a flexible spatial scan statistic implemented with a restricted likelihood ratio proposed by Tango (2008) to (1) eliminate the limitation of 30 nearest neighbors and (2) to have surprisingly much less computational time than the original flexible spatial scan statistic. As a side effect, it is shown to be able to detect clusters with any shape reasonably well as the relative risk of the cluster becomes large via Monte Carlo simulation. We illustrate the proposed spatial scan statistic with data on mortality from cerebrovascular disease in the Tokyo Metropolitan area, Japan. Copyright © 2012 John Wiley & Sons, Ltd.
A bias‐corrected covariance estimate for improved inference with quadratic inference functions
Authors: Westgate Philip M.
Published: July 2012

The method of quadratic inference functions (QIF) is an increasingly popular method for the analysis of correlated data because of its multiple advantages over generalized estimating equations (GEE). One advantage is that it is more efficient for parameter estimation when the working covariance structure for the data is misspecified. In the QIF literature, the asymptotic covariance formula is used to obtain standard errors. We show that in small to moderately sized samples, these standard error estimates can be severely biased downward, therefore inflating test size and decreasing coverage probability. We propose adjustments to the asymptotic covariance formula that eliminate finite‐sample biases and, as shown via simulation, lead to substantial improvements in standard error estimates, inference, and coverage. The proposed method is illustrated in application to a cluster randomized trial and a longitudinal study. Furthermore, QIF and GEE are contrasted via simulation and these applications. Copyright © 2012 John Wiley & Sons, Ltd.
Power of the Mantel–Haenszel and other tests for discrete or grouped time‐to‐event data under a chained binomial model
Authors: Lachin John M.
Published: July 2012

Power for time‐to‐event analyses is usually assessed under continuous‐time models. Often, however, times are discrete or grouped, as when the event is only observed when a procedure is performed. Wallenstein and Wittes (Biometrics, 1993) describe the power of the Mantel–Haenszel test for discrete lifetables under their chained binomial model for specified vectors of event probabilities over intervals of time. Herein, the expressions for these probabilities are derived under a piecewise exponential model allowing for staggered entry and losses to follow‐up.

Radhakrishna (Biometrics, 1965) showed that the Mantel–Haenszel test is maximally efficient under the alternative of a constant odds ratio and derived the optimal weighted test under other alternatives. Lachin (Biostatistical Methods: The Assessment of Relative Risks, 2011) described the power function of this family of weighted Mantel–Haenszel tests. Prentice and Gloeckler (Biometrics, 1978) described a generalization of the proportional hazards model for grouped time data and the corresponding maximally efficient score test. Their test is also shown to be a weighted Mantel–Haenszel test, and its power function is likewise obtained.

There is trivial loss in power under the discrete chained binomial model relative to the continuous‐time case provided that there is a modest number of periodic evaluations. Relative to the case of homogeneity of odds ratios, there can be substantial loss in power when there is substantial heterogeneity of odds ratios, especially when heterogeneity occurs early in a study when most subjects are at risk, but little loss in power when there is heterogeneity late in a study. Copyright © 2012 John Wiley & Sons, Ltd.
Extension of adaptive alpha allocation methods for strong control of the family‐wise error rate
Authors: Li Haihong , Sankoh Abdul J. , D'Agostino Ralph B.
Published: July 2012

With recent advancements in clinical trial design and the availability of rigorous statistical methods that provide strong control of the family‐wise type I error rate for multiple testing of hypotheses, it is now common for sponsors to design clinical trials with prospectively specified multiple testing of hypotheses of both primary and secondary endpoints and with the intent to obtain labeling claims for secondary endpoints. One of these recent advancements in multiple testing techniques is the adaptive alpha allocation approach (4A) proposed by Li and Mehrotra (Statistics in Medicine 2008; 27:5377–5391), which groups the hypotheses into two families on the basis of perceived trial power and allows the significance level for the second family to be set adaptively on the basis of the largest observed p‐value in the first family. We introduce a class of flexible functions that generalize the 4A procedure and can lead to relatively more powerful test statistics. In the case when the test statistics are correlated, we introduce well‐defined functions to calculate the significance level for the second family. The numerical computation for our methods is straightforward, making application in practice easy. Copyright © 2012 John Wiley & Sons, Ltd.
Null but not void: considerations for hypothesis testing
Authors: Shaw Pamela A. , Proschan Michael A.
Published: July 2012

Standard statistical theory teaches us that once the null and alternative hypotheses have been defined for a parameter, the choice of the statistical test is clear. Standard theory does not teach us how to choose the null or alternative hypothesis appropriate to the scientific question of interest. Neither does it tell us that in some cases, depending on which alternatives are realistic, we may want to define our null hypothesis differently. Problems in statistical practice are frequently not as pristinely summarized as the classic theory in our textbooks. In this article, we present examples in statistical hypothesis testing in which seemingly simple choices are in fact rich with nuance that, when given full consideration, make the choice of the right hypothesis test much less straightforward. Published 2012. This article is a US Government work and is in the public domain in the USA.
The trend‐renewal process: a useful model for medical recurrence data
Authors: Pietzner Diana , Wienke Andreas
Published: July 2012

Time‐to‐event data analysis has a long tradition in applied statistics. Many models have been developed for data where each subject or observation unit experiences at most one event during its life. In contrast, in some applications, the subjects may experience more than one event. Recurrent events appear in science, medicine, economy, and technology. Often the events are followed by a repair action in reliability or a treatment in life science. A model to deal with recurrent event times for incomplete repair of technical systems is the trend‐renewal process. It is composed of a trend and a renewal component. In the present paper, we use a Weibull process for both of these components. The model is extended to include a Cox type covariate term to account for observed heterogeneity. A further extension includes random effects to account for unobserved heterogeneity. We fit the suggested version of the trend‐renewal process to a data set of hospital readmission times of colon cancer patients to illustrate the method for application to clinical data. Copyright © 2012 John Wiley & Sons, Ltd.
Contrasting treatment‐specific survival using double‐robust estimators
Authors: Zhang Min , Schaubel Douglas E.
Published: July 2012

In settings where a randomized trial is infeasible, observational data are frequently used to compare treatment‐specific survival. The average causal effect (ACE) can be used to make inference regarding treatment policies on patient populations, and a valid ACE estimator must account for imbalances with respect to treatment‐specific covariate distributions. One method through which the ACE on survival can be estimated involves appropriately averaging over Cox‐regression‐based fitted survival functions. A second available method balances the treatment‐specific covariate distributions through inverse probability of treatment weighting and then contrasts weighted nonparametric survival function estimators. Because both methods have their advantages and disadvantages, we propose methods that essentially combine both estimators. The proposed methods are double robust, in the sense that they are consistent if at least one of the two working regression models (i.e., logistic model for treatment and Cox model for death hazard) is correct. The proposed methods involve estimating the ACE with respect to restricted mean survival time, defined as the area under the survival curve up to some prespecified time point. We derive and evaluate asymptotic results through simulation. We apply the proposed methods to estimate the ACE of donation‐after‐cardiac‐death kidney transplantation with the use of data obtained from multiple centers in the Netherlands. Copyright © 2012 John Wiley & Sons, Ltd.
Interconversion of Inverse Opals of Electrically Conducting Doped Titanium Oxides and Nitrides
Authors: Subban Chinmayee V. , Smith Ian C. , DiSalvo Francis J.
Published: July 2012

There is a need for conducting, porous, and chemically stable materials for technologies including, but not limited to, fuel cells, solar cells, and batteries. The need for catalyst support materials that are more durable than carbon black in fuel cells motivated previous studies of the synthesis, characterization, and corrosion resistance of Ti0.7W0.3O2 nanoparticles. However, because even higher porosity and increased electrical conductivity are desired, processes were developed to prepare rutile phase Ti0.7W0.3O2 and cubic Ti0.7W0.3N in inverse opal morphologies from a precursor inverse opal of very poorly conducting, amorphous Ti0.7W0.3O2.3. Inverse opals have been explored for a variety of applications from catalysis to photonics, and inverse opals of both oxides and nitrides have been reported. By synthesizing highly conducting mixed‐metal oxides and mixed‐metal nitrides, the applications of inverse opals can be broadened. Herein, the synthesis and characterization of polystyrene‐templated, single‐phase, crystalline inverse opals of Ti0.7W0.3O2 are reported. These conducting inverse opals can subsequently be converted to inverse opals of Ti0.7W0.3N and then fully oxidized back to inverse opals of the original insulating, amorphous Ti0.7W0.3O2.3. Such changes in composition and crystal structure, while successfully retaining the inverse opal morphology without the use of a supporting template during the conversion, have not been previously reported.
Nonsocial Transient Behavior: Social Disengagement on the Greyhound Bus
Authors: Kim Esther C.
Published: July 2012

Based on two years of observations and engaging in informal conversations with passengers on Greyhound Line buses, this article describes the long‐distance bus journey and the ways in which people actively disengage from others over the course of the ride. Using the Greyhound buses and stations as a microcosm of other such public spaces, I examine its unspoken rules and behavior. I paint a picture of the buses and stations, the patrons, the employees, and the transactions that take place between them. Using ideas from Goffman's civil inattention theory, Lofland's thoughts on strangers, and symbolic interactionism, I explain what I call “nonsocial transient behavior” and “nonsocial transient space.” The reasons nonsocial transient behavior emerges and thus encourages disengagement are identified as follows: uncertainty about strangers, lack of privacy or absence of a personal space, and exhaustion.
PROcedures for TESTing and measuring wind turbine components; results for yaw and pitch system and drive train
Authors: Holierhoek J.G. , Lekou D.J. , Hecquet T. , Söker H. , Ehlers B. , Savenije F.J. , Engels W.P. , van de Pieterman R.P. , Ristow M. , Kochmann M. , Smolders K. , Peeters J.
Published: July 2012

PROcedures for TESTing (PROTEST) and measuring wind energy systems) was a pre‐normative project that ran from 2008 to 2010 in order to improve the reliability of mechanical components of wind turbines. Initiating the project, it was concluded that the procedures concerning these components should be further improved. Within the PROTEST project, complementary procedures have been developed to improve the specification of the design loads at the interfaces where the mechanical components (pitch and yaw system, as well as the drive train) are attached to the wind turbine. This is required, since in optimizing wind turbine operation and improving reliability, focus should be given to the design, not only to safety related components but also to the rest of the components affecting the overall behaviour of the wind turbine as a system. The project has resulted in a proposal for new design load cases, specifically for the drive train, a description of the loads to be defined at the interfaces of each mechanical system, as well as a method to set up and use the prototype measurements to validate or improve the load calculations concerning the mechanical components. Following this method would improve the reliability of wind turbines, although more experience is needed to efficiently use the method. Examples are given for the analysis of the drive train, pitch system and yaw system. Copyright © 2012 John Wiley & Sons, Ltd.
Detection of nacelle anemometer faults in a wind farm minimizing the uncertainty
Authors: Beltrán J. , Guerrero J. J. , Melero J. J. , Llombart A.
Published: July 2012

The performance assessment of wind farms requires the acquisition of accurate power and wind speed data of each turbine. Nowadays, the nacelle anemometry is widely studied as an option for power performance verification. Therefore, systems to detect the nacelle anemometer faults in a wind farm in operation are necessary for maintenance purposes. In this paper, we propose a method to detect wind speed deviations of the nacelle anemometers by comparing them with the nearby anemometers. This comparison is made through an approach to estimate the wind speed in each nacelle. The approach is based on the discretization of wind speed data using the bin method. The key issue of this proposal is the estimation of the anemometer deviations considering the range of data with lower uncertainty. To this end, an average uncertainty model per bin and direction sector has been integrated into the method. The tests show that using wind speeds higher than 4.5 m s  − 1 gives the lowest uncertainty. Data from two wind farms have been used to test this method, and the obtained results have allowed the detection of problematic anemometers. Copyright © 2012 John Wiley & Sons, Ltd.
Stochastic dynamic response analysis of a tension leg spar‐type offshore wind turbine
Authors: Karimirad Madjid , Moan Torgeir
Published: July 2012

This paper presents a stochastic dynamic response analysis of a tension leg spar‐type wind turbine subjected to wind and wave actions. The dynamic motions, structural responses, power production and tension leg responses are analyzed. The model is implemented using the HAWC2 code. Several issues such as negative damping, rotor configuration (upwind or downwind rotor) and tower shadow effects are discussed to study the power performance and structural integrity of the system. The operational and survival load cases considering the stochastic wave and wind loading are analyzed to investigate the functionality of the tension leg spar‐type wind turbine. Amelioration of the negative damping applied for this concept reduces the structural dynamic responses, which are important for fatigue life. It is found that the responses induced by wave and wind actions at the wave frequencies are not affected much by the aerodynamic excitation or damping forces. Because of the nonlinear effects of the tension leg, all of the motion responses are strongly coupled. The global responses of upwind and downwind versions of the turbine are found to be close because the tower shadow has a limited effect on the global responses. However, the structural dynamic responses of the blades are more affected by the tower shadow. In this study, the extrapolation methods are applied to efficiently estimate the maximum responses. The maximum response is found to occur in the survival cases as a result of the wave actions and the increased aerodynamic drag forces on the tower. The results show that the maximum responses corresponding to the up‐crossing rate of 0.0001 (corresponding to the maximum response within a 3 hour period) can be expressed by the mean plus 3 to 5 standard deviations. Copyright © 2012 John Wiley & Sons, Ltd.
Analysis of the Hoard of Beçin using X‐ray‐based techniques
Authors: Rodrigues M. , Schreiner M. , Melcher M. , Guerra M. , Salomon J. , Radtke M. , Alram M. , Schindel N.
Published: July 2012

Four hundred and sixteen silver coins stemming from the Ottoman Empire (16th and 17th centuries) were analyzed to confirm the fineness of the coinage as well as to study the provenance of the alloy used for the coins. As most of the coins showed the typical green patina on their surfaces due to corrosion processes that have led to the depletion of copper in the near surface domains of the silver coins in comparison to their core composition, small samples had to be taken, embedded in synthetic resin, and cross sectioned to investigate the true‐heart metal composition. μ‐synchrotron micro X‐ray fluorescence analysis and μ‐proton‐induced X‐ray emission were applied to determine the silver contents as well as the minor and trace elements. The type of the alloy was investigated as well as if coins minted in different locations demonstrated homogeneous traits concerning the predominant impurities (Au and Bi), which could suggest a common ore. Finally, energy‐dispersive microanalysis in a scanning electron microscope was applied to study the homogeneity/heterogeneity of the coins and the presence of surface enrichments and to explain differences between the μ‐synchrotron micro X‐ray fluorescence analysis and μ‐proton‐induced X‐ray emission measurements concerning the main component. In general, the silver content of the analyzed specimen varies between 90 and 95%. These outcomes have not supported the historical interpretations, which predict that during the period studied, a debasement of approximately 44% of the silver content of the coins should have occurred. Copyright © 2012 John Wiley & Sons, Ltd.
Energetic Derivatives of 4, 4′,5, 5′‐Tetranitro‐2, 2′‐bisimidazole (TNBI)
Authors: Klapötke Thomas M. , Preimesser Andreas , Stierstorfer Jörg
Published: July 2012

4, 4′,5, 5′‐Tetranitro‐2, 2′‐bisimidazole (TNBI) was synthesized by nitration of bisimidazole (BI) and recrystallized from acetone to form a crystalline acetone adduct. Its ammonium salt (1) was obtained by the reaction with gaseous ammonia. In order to explore new explosives or propellants several energetic nitrogen‐rich 2:1 salts such as the hydroxylammonium (3), guanidinium (4), aminoguanidinium (5), diaminoguanidinium (6) and triaminoguanidinium 7 4, 4′,5, 5′‐tetranitro‐2, 2′‐bisimidazolate were prepared by facile metathesis reactions. In addition, methylated 1, 1′‐dimethyl‐4, 4′,5, 5′‐tetranitro‐2, 2′‐bisimidazole (Me2TNBI, 8) was synthesized by the reaction of 2 and dimethyl sulfate. Metal salts of TNBI can also be easily synthesized by using the corresponding metal bases. This was proven by the synthesis of pyrotechnically relevant dipotassium 4, 4′,5, 5′‐tetranitro‐2, 2′‐bisimidazolate (2), which is a brilliant burning component e.g. in near‐infrared flares. All compounds were characterized by single crystal X‐ray diffraction, NMR and vibrational spectroscopy, elemental analysis and DSC. The sensitivities were determined by BAM methods (drophammer and friction tester). The heats of formation were calculated using CBS‐4M electronic enthalpies and the atomization method. With these values and mostly the X‐ray densities different detonation parameters were computed by the EXPLO5 computer code. Due to the great thermal stability and calculated energetic properties, especially guanidinium salt 4 could be served as a HNS replacement.
LHC discovery potential for non-standard Higgs bosons in the 3b channel
Authors: Carena Marcela , Gori Stefania , Juste Aurelio , Menon Arjun , Wagner Carlos E.M. , Wang Lian-Tao
Published: July 2012

Abstract

In a variety of well motivated models, such as two Higgs Doublet Models (2HDMs) and the Minimal Supersymmetric Standard Model (MSSM), there are neutral Higgs bosons that have significantly enhanced couplings to b-quarks and tau leptons in comparison to those of the SM Higgs. These so called non-standard Higgs bosons could be copiously produced at the LHC in association with b quarks, and subsequently decay into b-quark pairs. However, this production channel suffers from large irreducible QCD backgrounds. We propose a new search strategy for non-standard neutral Higgs bosons at the 7 TeV LHC in the 3b’s final state topology. We perform a simulation of the signal and backgrounds, using state of the art tools and methods for different sets of selection cuts, and conclude that neutral Higgs bosons with couplings to b-quarks of about 0.3 or larger, and masses up to 400 GeV, could be seen with a luminosity of 30 fb−1. In the case of the MSSM we also discuss the complementarity between the 3b channel and the inclusive tau pair channel in exploring the supersymmetric parameter space.
Use of Furandicarboxylic Acid and Its Decyl Ester as Additives in the Fischer's Glycosylation of Decanol by d‐Glucose: Physicochemical Properties of the Surfactant Compositions Obtained
Authors: van Es Daan S. , Marinkovic Sinisa , Oduber Xavier , Estrine Boris
Published: July 2012

2,5‐Furandicarboxylic acid is a promising bio‐based platform chemical that may serve as a ‘green’ substitute for terephthalate in polyesters. In the present work, straightforward glycosylation of decanol with unprotected and non‐activated d‐glucose was performed under reduced quantities of sulfuric acid as catalyst (down to 0.9 mol%) in the presence of 2,5‐furandicarboxylic acid or its n‐decyl ester as additive. Yield of decyl monoglucosides was highly improved by the use of the additives. Moreover, the presence of additive also limited the colouration of the reaction. The physical and chemical properties of the surfactant composition produced were studied and compared to reference compositions. The ultimate biodegradability of furan‐2,5‐dicarboxylic acid (FDCA) and its n‐decyl ester formed or produced in the bulk reaction medium was also studied in order to assess its potential use in surfactant industry.
Novel FixL homologues in Chlamydomonas reinhardtii bind heme and O2
Authors: Murthy U.M. Narayana , Wecker Matt S.A. , Posewitz Matthew C. , Gilles-Gonzalez Marie-Alda , Ghirardi Maria L.
Published: July 2012

Genome inspection revealed nine putative heme‐binding, FixL‐homologous proteins in Chlamydomonas reinhardtii. The heme‐binding domains from two of these proteins, FXL1 and FXL5 were cloned, expressed in Escherichia coli, purified and characterized. The recombinant FXL1 and FXL5 domains stained positively for heme, while mutations in the putative ligand‐binding histidine FXL1‐H200S and FXL5‐H200S resulted in loss of heme binding. The FXL1 and FXL5 [Fe(II), bound O2] had Soret absorption maxima around 415 nm, and weaker absorptions at longer wavelengths, in concurrence with the literature. Ligand‐binding measurements showed that FXL1 and FXL5 bind O2 with moderate affinity, 135 and 222 μM, respectively. This suggests that Chlamydomonas may use the FXL proteins in O2‐sensing mechanisms analogous to that reported in nitrogen‐fixing bacteria to regulate gene expression.
Methyl donor deficiency affects small-intestinal differentiation and barrier function in rats
Authors: Bressenot Aude , Pooya Shabnam , Bossenmeyer-Pourie Carine , Gauchotte Guillaume , Germain Adeline , Chevaux Jean-Baptiste , Coste Florence , Vignaud Jean-Michel , Guéant Jean-Louis , Peyrin-Biroulet Laurent
Published: July 2012

Dietary methyl donors and their genetic determinants are associated with Crohn's disease risk. We investigated whether a methyl-deficient diet (MDD) may affect development and functions of the small intestine in rat pups from dams subjected to the MDD during gestation and lactation. At 1 month before pregnancy, adult females were fed with either a standard food or a diet without vitamin B12, folate and choline. A global wall hypotrophy was observed in the distal small bowel (MDD animals 0·30 mmv. controls 0·58 mm;P< 0·001) with increased crypt apoptosis (3·37v. 0·4 %;P< 0·001), loss of enterocyte differentiation in the villus and a reduction in intestinal alkaline phosphatase production. Cleaved caspase-3 immunostaining (MDD animals 3·37 %v. controls 0·4 %,P< 0·001) and the Apostain labelling index showed increased crypt apoptosis (3·5v. 1·4 %;P= 0·018). Decreased proliferation was observed in crypts of the proximal small bowel with a reduced number of minichromosome maintenance 6 (MDD animals 52·83 %v. controls 83·17 %;P= 0·048) and proliferating cell nuclear antigen-positive cells (46·25v. 59 %;P= 0·05). This lack of enterocyte differentiation in the distal small bowel was associated with an impaired expression of β-catenin and a decreased β-catenin–E-cadherin interaction. The MDD affected the intestinal barrier in the proximal small bowel by decreasing Paneth cell number after immunostaining for lysosyme (MDD animals 8·66 %v. controls 21·66 %) and by reducing goblet cell number and mucus production after immunostaining for mucin-2 (crypts 8·66v. 15·33 %; villus 7v. 17 %). The MDD has dual effects on the small intestine by producing dramatic effects on enterocyte differentiation and barrier function in rats.