bluuebunny/crossref_metadata_2025 huggingface dataset:
Soluble dithienothiophene polymers: Effect of link pattern
Authors: Zhang Shiming , Fan Haijun , Liu Yao , Zhao Guangjin , Li Qikai , Li Yongfang , Zhan Xiaowei
Published: April 2009

Soluble conjugated polymers based on 3,5‐didecanyldithieno[3,2‐b:2′,3′‐d]thiophene—single‐bond (1), double‐bond (2), and triple‐bond linked (3)—were synthesized by palladium(0)‐catalyzed Stille coupling reaction and oxidation polymerization. The thermal, absorption, emission, and electrochemical properties of these polymers were examined; the effect of the link pattern was studied. All polymers exhibit decomposition temperatures over 295 °C and glass‐transition temperatures in the range of 137–202 °C. The absorption spectra of 1, 2, and 3 in thin films exhibit absorption maxima at 381, 584, and 444 nm, respectively. Polymer 1 exhibits intense green emission located at 510 nm in film, whereas polymers 2 and 3 are nonemissive both in solution and in film due to H‐aggregate. Cyclic voltammograms of polymers 1, 2, and 3 display irreversible oxidation waves with onset oxidation potentials at 1.73, 0.78, and 1.03 V versus Ag+/Ag, respectively. Theory calculation on model compounds suggests that the dihedral angle decreases in the order of 1 > 3 > 2. On reducing the dihedral angle, the polymer exhibits a longer absorption maximum, a smaller bandgap, a less oxidizing potential and fluorescence quench, due to more coplanar and more π‐electron delocalized backbone structure. Polymer solar cells were fabricated based on the blend of polymer 2 and methanofullerene [6,6]‐phenyl C61‐butyric acid methyl ester (PCBM). The power conversion efficiency of 0.45% was achieved under AM 1.5, 100 mW cm−2 using polymer 2:PCBM (1:2, w/w) as active layer. © 2009 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 47: 2843–2852, 2009
The Norwegian version of the Mini‐Mental Adjustment to Cancer Scale: factor structure and psychometric properties
Authors: Bredal Inger Schou
Published: April 2009

Objective: The object of the study was to examine the factor structure and the psychometric properties of the Mini‐Mental Adjustment to Cancer Scale (Mini‐MAC) among a large sample of Norwegian breast cancer patients.

Methods: A total of 402 patients with breast cancer completed the Mini‐MAC.

Results: Principal component analysis with varimax rotion confirmed four factors. Three had psychometric properties to the original Mini‐MAC Helpless‐Hopeless (HH), Anxious Preoccupation (AP) and Cognitive Avoidance (CA) subscales. The fourth, named Positive Attitude (PA) combined the Fighting Spirit (FS) and the Fatalism subscales of the original Mini‐MAC. Construct validities were assessed by examining the interscale correlations as well as the correlations between the Mini‐MAC subscales and the HADS subscales scores. Internal consistency of the five subscales was satisfactory for the original (HH, AP, CA, FA, coefficients=0.60‐0.83), except for the FS subscale (coefficient=21).

Conclusion: In view of the low internal reliability for the Norwegian Mini‐MAC FS subscale coefficient; it appears to be more appropriate to use the Norwegian Mini‐MAC as a four‐factor model. If researcher or clinicians in Norway use the five‐factor model, they should take great care when interpreting the fighting spirit subscale. Copyright © 2009 John Wiley & Sons, Ltd.
Psychological interventions with siblings of pediatric cancer patients: a systematic review
Authors: Prchal Alice , Landolt Markus A.
Published: April 2009

Objective: Siblings of pediatric cancer patients have been shown to be at risk for developing emotional, behavioral, and social problems. There is a need for psychological interventions in this population. Several researchers have previously documented and evaluated their interventions with siblings. This paper aimed at reviewing the existing reports of evaluated psychological interventions with siblings of pediatric cancer patients and at outlining future directions.

Methods: Research was conducted on several online bibliographic databases. Articles were selected on the basis of predefined criteria. If possible, effect sizes (ES) were calculated.

Results: Fourteen studies representing 11 different sibling interventions met criteria for inclusion. One individual intervention, three camps, and seven groups were found. Objectives of interventions concentrated mainly on enhancing siblings' coping and improving their medical knowledge. In terms of outcome measures, most of the studies focused on psychological adjustment variables. Findings showed significant improvements in siblings' depression symptomatology, medical knowledge, and health‐related quality of life. Findings were inconsistent with regard to anxiety, behavioral problems, social adjustment, self‐esteem, and posttraumatic stress symptoms. Depending on the outcome variables, small to large ES were found. Satisfaction with the intervention was high in both siblings and parents.

Conclusion: There is tentative evidence that psychological interventions with siblings of childhood cancer patients can effectively reduce psychological maladjustment and improve medical knowledge about cancer. However, the number of studies is small, and several methodological shortcomings have to be noted. In future, more randomized controlled trials need to be conducted in larger samples to extend the evidence base. Copyright © 2009 John Wiley & Sons, Ltd.
Cancer patients' desire for psychological support: prevalence and implications for screening patients' psychological needs
Authors: Merckaert Isabelle , Libert Yves , Messin Sophie , Milani Mina , Slachmuylder Jean‐Louis , Razavi Darius
Published: April 2009

Objectives: To investigate cancer patients' desire for psychological support and to identify patients' sociodemographic, disease‐related and psychological factors associated with this desire.

Methods: The study is part of a multicenter, cross‐sectional study assessing cancer patients' needs and desire for psychological support. Patients completed the Hospital Anxiety and Depression Scale, the Ways of Coping Checklist, the Cancer Rehabilitation Evaluation System and reported their desire for psychological support.

Results: Among the 381 included patients, women (26%) desired psychological support significantly more often than men (11%) (p<0.001). Patients' desire for psychological support was associated with being younger (OR=0.94; p<0.001 for women and OR=0.93; p=0.007 for men) and having a support‐seeking coping (OR=1.10; p=0.010 for women and OR=1.36; p=0.003 for men). Other contextual factors such as difficulties encountered and treatment modalities were diversely associated with women and men's desire for psychological support. Neither women's, nor men's psychological distress was associated with their desire for psychological support.

Conclusions: One female cancer patient out of four and one male cancer patient out of ten desire psychological support. Results emphasize the need to screen not only for cancer patients' distress but also for their desire for psychological support. This will allow implementing psychological interventions according to patients' needs and desire. Copyright © 2009 John Wiley & Sons, Ltd.
Motives that cancer patients in oncological care have for consulting a psychologist—an empirical study
Authors: Salander Pär
Published: April 2009

Objective: Most people with cancer are able to deal with the mental turmoil with support from ordinary health care, family and friends. However, by themselves or by attentive health‐care workers some patients are referred to specialists within the psychosocial field, foremost social workers and psychologists. This paper deals with patients' motives for seeing a psychologist.

Methods: The case books for all patients who had met with the psychologist at a department of oncology in Sweden during a 10‐year period were read through and categorised according to what the patients wanted to talk about.

Results: The most commonly found motives were in sliding order: coping with anxiety and worries caused by the disease; dealing with relational problems in life outside the disease; dealing with relational problems actualised by the disease; living with a malignant disease‐despair in a new life situation; and finally dealing with a particular problem.

Conclusion: Patients seeing a psychologist in oncology do not just ask for help to come to terms with anxiety and worries. More than a third of the patients wanted to talk about distressing relationships, which were not connected to, or only remotely connected to the cancer disease. Patients have different needs and competence in different psychological treatment perspectives is therefore important. The found diversity of motives bears impact on the external validity of screening instruments for distress and randomised controlled intervention studies. Copyright © 2009 John Wiley & Sons, Ltd.
Psychological distress and use of psychosocial support in familial adenomatous polyposis
Authors: Douma Kirsten F. L. , Aaronson Neil K. , Vasen Hans F. A. , Gerritsma Miranda A. , Gundy Chad M. , Janssen Esther P. A. , Vriends Annette H. J. T. , Cats Annemieke , Verhoef Senno , Bleiker Eveline M. A.
Published: April 2009

Objective: Familial adenomatous polyposis (FAP) is characterized by multiple adenomas in the colorectum with a high risk to develop colorectal cancer. It is unclear whether individuals at risk of FAP experience distress due to this potentially life‐threatening disease. This nationwide study assessed: (1) the prevalence of psychological distress; and (2) the need for and use of specialized professional psychosocial support.

Methods: In this cross‐sectional study, all individuals from families at high risk for FAP registered at the Netherlands Foundation for the Detection of Hereditary Tumours were invited to complete a questionnaire assessing, among other issues, generalized, cancer‐specific and FAP‐specific distress.

Results: In total, 525 individuals completed the questionnaire. Approximately 20% of the respondents had moderate to severe levels of FAP‐specific distress. Levels of generalized distress were comparable to the general Dutch population. Significantly more individuals with a FAP diagnosis had frequent cancer worries than those at risk of FAP or non‐carriers (p=0.02). Distress levels were more strongly associated with psychosocial variables (e.g. perceived cancer risk), than with sociodemographic or clinical variables. Up to 43% of the variance in distress could be explained by all variables combined. Of those moderately to severely distressed, 26% had received specialized professional psychosocial support, while 30% of those did not receive the support they wanted.

Conclusions: A substantial minority of individuals reported moderate to severe distress levels associated with FAP. However, only one‐third of those received specialized professional psychosocial support. We recommend the use of a screening questionnaire to identify individuals in need of such support. Copyright © 2009 John Wiley & Sons, Ltd.
Nanosecond Pulsed Plasma Dental Probe
Authors: Jiang Chunqi , Chen Meng‐Tse , Gorur Amita , Schaudinn Christoph , Jaramillo David E. , Costerton J. William , Sedghizadeh Parish P. , Vernier P. Thomas , Gundersen Martin A.
Published: April 2009

A novel coaxial tubular device capable of generating a 2.5 cm long pencil‐like plasma plume in ambient atmosphere has recently been developed to disinfect root canal systems during endodontic treatment. Powered with short (≈100 ns), intense (6 kV) electric pulses at 1 kHz, the plasma dental probe is safe for operation, electromagnetic noise‐free, with low power consumption (an average power of ≈1 W) and minimal heating of materials under treatment. It thus has the essential features required for oral and dental disinfection. In this communication, we present the design of the device and evidence that the plasma dental probe is effective for tooth surface disinfection. Scanning electron microscopy shows complete destruction of endodontic biofilms for a depth of 1 mm inside a root canal after plasma treatment for 5 min. Plasma emission spectroscopy identifies atomic oxygen as one of the likely active agents for the bactericidal effect.

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Computer Modeling of Plasmas and Plasma‐Surface Interactions
Authors: Bogaerts Annemie , Bultinck Evi , Eckert Maxie , Georgieva Violeta , Mao Ming , Neyts Erik , Schwaederlé Laurent
Published: April 2009

In this paper, an overview is given of different modeling approaches used for describing gas discharge plasmas, as well as plasma‐surface interactions. A fluid model is illustrated for describing the detailed plasma chemistry in capacitively coupled rf discharges. The strengths and limitations of Monte Carlo simulations and of a particle‐in‐cell–Monte Carlo collisions model are explained for a magnetron discharge, whereas the capabilities of a hybrid Monte Carlo–fluid approach are illustrated for a direct current glow discharge used for spectrochemical analysis of materials. Finally, some examples of molecular dynamics simulations, for the purpose of plasma‐deposition, are given.

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Film Deposition in the Dielectric Barrier Discharge at Atmospheric Pressure in He/O2/HMDSO and He/N2O/HMDSO mixtures
Authors: Vinogradov Igor , Lunk Achim
Published: April 2009

Non‐thermal dielectric barrier discharges (DBD) operated in a parallel plate reactor (6 cm width and 16 cm long) under atmospheric pressure in He/O2/HMDSO and He/N2O/HMDSO mixtures at different O2 or N2O to HMDSO (hexamethyldisiloxane) ratios and different power are studied. The effective power of the discharge was derived by evaluating the Lissajous–figure on the oscilloscope. Emission spectroscopy and FTIR‐absorption spectroscopy were applied to get information on the reaction products in DBD. The spectroscopic gas analysis was performed at three residence times. The properties of the polymer films deposited on silicon wafers were measured by FTIR‐absorption spectroscopy, AFM and XPS analysis. Surface tension was obtained by contact angle measurements with water. Correlations between parameters of plasma phase with film parameters are discussed.
Crystal structure of phenylacetic acid degradation protein PaaG from Thermus thermophilus HB8
Authors: Kichise Tomoyasu , Hisano Tamao , Takeda Kazuki , Miki Kunio
Published: April 2009

Microbial degradation of phenylacetic acid proceeds via the hybrid pathway that includes formation of a coenzyme A thioester, ring hydroxylation, non‐oxygenolytic ring opening, and β‐oxidation‐like reactions. A phenylacetic acid degradation protein PaaG is a member of the crotonase superfamily, and is a candidate non‐oxygenolytic ring‐opening enzyme. The crystal structure of PaaG from Thermus thermophilus HB8 was determined at a resolution of 1.85 Å. PaaG consists of three identical subunits related by local three‐fold symmetry. The monomer is comprised of a spiral and a helical domain with a fold characteristic of the crotonase superfamily. A putative active site residue, Asp136, is situated in an active site cavity and surrounded by several hydrophobic and hydrophilic residues. The active site cavity is sufficiently large to accommodate a ring substrate. Two conformations are observed for helix H2 located adjacent to the active site. Helix H2 is kinked at Asn81 in two subunits, whereas it is kinked at Leu77 in the other subunit, and the side chain of Tyr80 is closer to Asp136. This indicates that catalytic reaction of PaaG may proceed with large conformational changes at the active site. Asp136 is the only conserved polar residue in the active site. It is located at the same position as those of 4‐chlorobenzoyl‐CoA dehalogenase and peroxisomal Δ3,Δ2‐enoyl‐CoA isomerase, indicating that PaaG may undergo isomerization or a ring‐opening reaction via a Δ3,Δ2‐enoyl‐CoA isomerase‐like mechanism. Proteins 2009. © 2009 Wiley‐Liss, Inc.
Structure is three to ten times more conserved than sequence—A study of structural response in protein cores
Authors: Illergård Kristoffer , Ardell David H. , Elofsson Arne
Published: April 2009

Protein structures change during evolution in response to mutations. Here, we analyze the mapping between sequence and structure in a set of structurally aligned protein domains. To avoid artifacts, we restricted our attention only to the core components of these structures. We found that on average, using different measures of structural change, protein cores evolve linearly with evolutionary distance (amino acid substitutions per site). This is true irrespective of which measure of structural change we used, whether RMSD or discrete structural descriptors for secondary structure, accessibility, or contacts. This linear response allows us to quantify the claim that structure is more conserved than sequence. Using structural alphabets of similar cardinality to the sequence alphabet, structural cores evolve three to ten times slower than sequences. Although we observed an average linear response, we found a wide variance. Different domain families varied fivefold in structural response to evolution. An attempt to categorically analyze this variance among subgroups by structural and functional category revealed only one statistically significant trend. This trend can be explained by the fact that beta‐sheets change faster than alpha‐helices, most likely due to that they are shorter and that change occurs at the ends of the secondary structure elements. Proteins 2009. © 2009 Wiley‐Liss, Inc.
Characterization of cancer‐linked BRCA1‐BRCT missense variants and their interaction with phosphoprotein targets
Authors: Drikos Ioannis , Nounesis George , Vorgias Constantinos E.
Published: April 2009

The breast cancer tumor suppressor protein BRCA1 is involved in DNA repair and cell cycle control. Mutations at the two C‐terminal tandem (BRCT) repeats of BRCA1 detected in breast tumor patients were identified either to lower the stability of the BRCT domain and/or to disrupt the interaction of BRCT with phoshpopeptides. The aim of this study was to analyze five BRCT pathogenic mutations for their effect on structural integrity and protein stability. For this purpose, the five cancer‐associated BRCT mutants: V1696L, M1775K, M1783T, V1809F, and P1812A were cloned in suitable prokaryotic protein production vectors, and the recombinant proteins were purified in soluble and stable form for further biophysical studies. The biophysical analysis of the secondary structure and the thermodynamic stability of the wild‐type, wt, and the five mutants of the BRCT domain were performed by Circular Dichroism Spectroscopy (CD) and Differential Scanning Microcalorimetry (DSC), respectively. The binding capacity of the wt and mutant BRCT with (pBACH1/BRIP1) and pCtIP were measured by Isothermal Titration Calorimetry (ITC). The experimental results demonstrated that the five mutations of the BRCT domain: (i) affected the thermal unfolding temperature as well as the unfolding enthalpy of the domain, to a varying degree depending upon the induced destabilization and (ii) altered and/or abolished their affinity to synthetic pBACH1/BRIP1 and pCtIP phosphopeptides by affecting the structural integrity of the BRCT active sites. The presented experimental results are one step towards the elucidation of the effect of various missense mutations on the structure and function of BRCA1‐BRCT. Proteins 2009. © 2009 Wiley‐Liss, Inc.
Insights into lid movements of Burkholderia cepacia lipase inferred from molecular dynamics simulations
Authors: Barbe Sophie , Lafaquière Vincent , Guieysse David , Monsan Pierre , Remaud‐Siméon Magali , André Isabelle
Published: April 2009

The interfacial activation of many lipases at water/lipid interface is mediated by large conformational changes of a so‐called lid subdomain that covers up the enzyme active site. Here we investigated using molecular dynamic simulations in different explicit solvent environments (water, octane and water/octane interface) the molecular mechanism by which the lid motion of Burkholderia cepacia lipase might operate. Although B. cepacia lipase has so far only been crystallized in open conformation, this study reveals for the first time the major conformational rearrangements that the enzyme undergoes under the influence of the solvent, which either exposes or shields the active site from the substrate. In aqueous media, the lid switches from an open to a closed conformation while the reverse motion occurs in organic environment. In particular, the role of a subdomain facing the lid on B. cepacia lipase conformational rearrangements was investigated using position‐restrained MD simulations. Our conclusions indicate that the sole mobility of α9 helix side‐chains of B. cepacia lipase is required for the full completion of the lid conformational change which is essentially driven by α5 helix movement. The role of selected α5 hydrophobic residues on the lid movement was further examined. In silico mutations of two residues, V138 and F142, were shown to drastically modify the conformational behavior of B. cepacia lipase. Overall, our results provide valuable insight into the role played by the surrounding environment on the lid conformational rearrangement and the activation of B. cepacia lipase. Proteins 2009. © 2009 Wiley‐Liss, Inc.
LOPA misapplied: Common errors can lead to incorrect conclusions
Authors: Study Karen A. , Champion John W.
Published: April 2009

Layer of Protection Analysis is a powerful tool for quantitative risk assessments. If applied correctly, it can provide quick and efficient guidance on what additional safeguards are needed, if any, to protect against a given scenario. If misapplied, an overly conservative calculation of risk may result in over‐instrumentation, additional life‐cycle costs, and spurious trips. A nonconservative calculation of risk could result in an under‐protected system and unacceptable risk of an undesired consequence occurring.

This article describes several categories of common errors, some overly conservative and some nonconservative. Case studies of actual plant scenarios are used to illustrate. © 2009 American Institute of Chemical Engineers Process Saf Prog 2009
Changing the way we advise patients on use of topical steroids
Authors: Bewley Anthony
Published: April 2009

Patients are confused about the appropriate application of topical steroids and may worry unnecessarily. In this article, a working group of dermatology experts provide advice for health professionals on how best to advise patients on their effective use. Copyright © 2009 Wiley Interface Ltd
The Faculty of Prescribing and Medicines Management
Authors: Strickland‐Hodge Barry
Published: April 2009

Barry Strickland‐Hodge describes the aims of The Faculty of Prescribing and Medicines Management and the benefits of becoming a member. Copyright © 2009 Wiley Interface Ltd
Modulation of protein–ligand interactions by photocleavage of a cyclic peptide using phosphatidylinositol 3‐kinase SH3 domain as model system
Authors: Takahashi Isao , Kuroiwa Shigeki , Lindfors Hanna E. , Ndamba Lionel A. , Hiruma Yoshitaka , Yajima Tatsuo , Okishio Nobuyuki , Ubbink Marcellus , Hirota Shun
Published: April 2009

To photomodulate the interaction of the phosphatidylinositol 3‐kinase SH3 domain with a peptide ligand, a cyclic peptide (cyclic‐1) with a photolabile side chain‐to‐side chain linker was synthesized. The conformation of cyclic‐1 differs from that of the parent linear peptide, but becomes identical by UV‐irradiation. Accordingly, the binding affinity of cyclic‐1 to the SH3 domain increased upon conversion of the cyclic to a linear flexible structure by irradiation (Kd: 3.4 ± 1.7 and 0.9 ± 0.3 mM, respectively). These results confirm the usefulness of a photocleavable peptide for photocontrol of peptide–protein interactions. Copyright © 2009 European Peptide Society and John Wiley & Sons, Ltd.
Aspartic acid scaffold in bradykinin B1 antagonists
Authors: Huszár József , Timár Zoltán , Bogár Ferenc , Penke Botond , Kiss Róbert , Szalai Krisztina Katalin , Schmidt Éva , Papp Andrea , Keserű György
Published: April 2009

Several novel bradykinin B1 receptor (B1R) antagonists were synthesized utilizing a new aspartic acid scaffold. This core is derived from the highly potent dihydroquinoxalinone scaffold published recently by researchers at Merck (Haet al. Biochem. Biophys. Res. Commun.2005, 331, 159–166). Despite the considerably limited chemical space of B1 antagonists, the synthesized compounds still showed significant biological activity. None of the four most potent compounds showed significant activity on the bradykinin B2 receptor (B2R), consequently they can be considered as valuable starting points for designing more potent and selective B1 antagonists. Furthermore, the synthesis of these aspartic acid derivatives is much simpler than that of the original Merck compounds suggesting efficient parallel synthesis approaches during their optimization. Docking known and novel B1 antagonists into the refined B1R homology model including the second extracellular loop (EC2) underlined the importance of this loop in ligand binding. Comparative binding mode analysis revealed that our novel compounds bind similar to the dihydroquinoxalinone template. Our results indicate that the rigid core of the dihydroquinoxalinone containing B1 antagonists is not crucial for maintaining B1 activity. Copyright © 2009 European Peptide Society and John Wiley & Sons, Ltd.
Room‐temperature epitaxial growth of high‐quality m ‐plane InGaN films on ZnO substrates
Authors: Shimomoto Kazuma , Kobayashi Atsushi , Ueno Kohei , Ohta Jitsuo , Oshima Masaharu , Fujioka Hiroshi , Amanai Hidetaka , Nagao Satoru , Horie Hideyoshi
Published: April 2009

The authors have grown high‐quality m ‐plane In0.36Ga0.64N (1$ \bar 1 $00) films on ZnO (1$ \bar 1 $00) substrates at room temperature (RT) by pulsed laser deposition (PLD) and have investigated their structural properties. m ‐plane InGaN films grown on ZnO substrates at RT possess atomically flat surfaces with stepped and terraced structures, indicating that the film growth proceeds in a two‐dimensional mode. X‐ray diffraction measurements have revealed that the m ‐plane InGaN films grow without phase separation reactions at RT. The full‐width at half‐maximum values of the 1$ \bar 1 $00 X‐ray rocking curves of films with X‐ray incident azimuths perpendicular to the c ‐ and a‐axis are 88 arcsec and 78 arcsec, respectively. Reciprocal space‐mapping has revealed that a 50 nm thick m ‐plane In0.36Ga0.64N film grows coherently on the ZnO substrate, which can probably explain the low defect density that is observed in the film. (© 2009 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Will quantum chemistry benefit from quantum computers?
Authors: Kaijser Per
Published: April 2009

This article provides a short review over Quantum Computers and their potential capabilities. It explains and discusses some areas for which they have or might have advantages over conventional computers. Special interest is devoted to their potential in solving scientific problems and in particular what they might do for quantum chemistry. © 2009 Wiley Periodicals, Inc. Int J Quantum Chem, 2009
Composite disturbance‐observer‐based control andH∞control for complex continuous models
Authors: Wei Xinjiang , Guo Lei
Published: April 2009

A novel type of control scheme combining the disturbance‐observer‐based control (DOBC) withH∞control is proposed for a class of complex continuous models with disturbances. The disturbances are supposed to include two parts. One part in the input channel is generated by an exogenous system with uncertainty, which can represent the harmonic signals with modeling perturbations. The other part is supposed to have the boundedH2‐norm. Parametric uncertainties exist both in concerned plant and in exogenous subsystem. The disturbance observers based on regional pole placement and D‐stability theory are designed and integrated with conventionalH∞control laws. The new composite DOBC andH∞control scheme is applied to complex continuous models for the case with known and unknown nonlinearity, respectively. Then the first type of disturbances can be estimated and rejected, and the second type can be attenuated; simultaneously, the desired dynamic performances can be guaranteed. Simulations for a flight control system are given to demonstrate the effectiveness of the results and compare the proposed results with the previous schemes. Copyright © 2009 John Wiley & Sons, Ltd.
Tracking control for sampled‐data systems with uncertain time‐varying sampling intervals and delays
Authors: van de Wouw N. , Naghshtabrizi P. , Cloosterman M. B. G. , Hespanha J. P.
Published: April 2009

In this paper, a solution to the approximate tracking problem of sampled‐data systems with uncertain, time‐varying sampling intervals and delays is presented. Such time‐varying sampling intervals and delays can typically occur in the field of networked control systems. The uncertain, time‐varying sampling and network delays cause inexact feedforward, which induces a perturbation on the tracking error dynamics, for which a model is presented in this paper. Sufficient conditions for the input‐to‐state stability (ISS) of the tracking error dynamics with respect to this perturbation are given. Hereto, two analysis approaches are developed: a discrete‐time approach and an approach in terms of delay impulsive differential equations. These ISS results provide bounds on the steady‐state tracking error as a function of the plant properties, the control design and the network properties. Moreover, it is shown that feedforward preview can significantly improve the tracking performance and an online extremum seeking (nonlinear programming) algorithm is proposed to online estimate the optimal preview time. The results are illustrated on a mechanical motion control example showing the effectiveness of the proposed strategy and providing insight into the differences and commonalities between the two analysis approaches. Copyright © 2009 John Wiley & Sons, Ltd.
Processing spectral data
Authors: Görlitz L. , Menze B. H. , Kelm B. M. , Hamprecht F. A.
Published: April 2009

Spectral images offer more information on complex probes than either conventional imagery (yielding only one or few measurements per voxel) or conventional spectroscopy (resulting in only one or a few spectra per probe) can. Spectral imaging is thus starting to become ubiquitous in areas ranging from materials science and process control to remote sensing and medicine. However, the information concealed in the massive amount of data generated by spectral imaging is not as easily accessible as in conventional (gray value or color) images and as in conventional spectroscopy, hence calling for new methods to analyze and visualize spectral images.

Broadly speaking, analysis methods can be classified in terms of the information used in the training phase, and by the extent to which they use spatial context in the analysis. This article gives a brief overview of ‘unsupervised’ methods that require sample spectral images during the training stage as well as specification of a degree of complexity of the sample, either in terms of number of cluster centers or intrinsic dimensionality of the data [principal component analysis (PCA)]. ‘Supervised’ methods, on the other hand, require a training set in which a class membership, or label, is available for each pixel. Our discussion includes methods that deal well with the high dimensionality and high degree of correlation among individual features, such as partial least squares (PLS) and linear discriminant analysis (LDA).

All of the above methods ignore the spatial context when applied to individual spectra. Often, the label map can be assumed to exhibit some spatial coherence, a fact that can help in classifying low quality spectra and that can be exploited using conditional or Markov random fields. The methods are illustrated using examples from automated process control and quantitative medical diagnostics. Copyright © 2009 John Wiley & Sons, Ltd.
Polarization Portraits of Single Multichromophoric Systems: Visualizing Conformation and Energy Transfer
Authors: Mirzov Oleg , Bloem Elin , Hania Peter Ralph , Thomsson Daniel , Lin Hongzhen , Scheblykin Ivan G.
Published: April 2009

A novel technique, two‐dimensional (2D) polarization single‐molecule imaging, is presented. It is based on measurements and analysis of fluorescence intensity as a function of excitation and emission polarization angles. The technique allows recording of full information on the steady‐state polarization properties of fluorescent objects. It is particularly suitable for application to single multichromophoric systems (molecules or nanoparticles) with energy transfer (ET) between different chromophores (e.g., single fluorescent π‐conjugated polymer chains). The 2D polarization data simultaneously provide information on the conformation of the system and the efficiency of its internal excitation ET. The technique is used to characterize single chains and different kinds of chain aggregates of different conjugated polymers at different temperatures. The 2D polarization measurements reveal a dramatic difference in ET taking place in these systems. Clear temperature dependence of ET is observed for individual aggregates as well as for their statistical ensembles. Also, a dependence on solvent and aggregate size is shown. Additionally, extensive “traditional one‐dimensional” polarization results on the polarization anisotropy of fluorescence excitation and emission are presented. These results and findings are discussed in relation to internal organization of the nano‐objects under study.
Polyaniline/Pt Hybrid Nanofibers: High‐Efficiency Nanoelectrocatalysts for Electrochemical Devices
Authors: Guo Shaojun , Dong Shaojun , Wang Erkang
Published: April 2009

A simple and facile procedure to synthesize a novel hybrid nanoelectrocatalyst based on polyaniline (PANI) nanofiber‐supported supra‐high density Pt nanoparticles (NPs) or Pt/Pd hybrid NPs without prior PANI nanofiber functionalization at room temperature is demonstrated. This represents a new type of 1D hybrid nanoelectrocatalyst with several important benefits. First, the procedure is very simple and can be performed at room temperature using commercially available reagents without the need for templates and surfactants. Second, ultra‐high density small “bare” Pt NPs or Pt/Pd hybrid NPs are grown directly onto the surface of the PANI nanofiber, without using any additional linker. Most importantly, the present PANI nanofiber‐supported supra‐high density Pt NPs or Pt/Pd hybrid NPs can be used as a signal enhancement element for constructing electrochemical devices with high performance.
Biosensing by Densely Packed and Optically Coupled Plasmonic Particle Arrays
Authors: Sannomiya Takumi , Sahoo Pratap K. , Mahcicek Davut I. , Solak Harun H. , Hafner Christian , Grieshaber Dorothee , Vörös Janos
Published: April 2009

Densely packed plasmonic particle arrays are investigated for biosensing applications. Such particle arrays exhibit interparticle optical coupling creating a strong field between the particles, which is useful for sensing purposes. The sensor properties, such as bulk sensitivity, layer sensitivity, and the depth of sensitivity are investigated with the aid of a multiple multipole program. Sensitivity to the analyte with low concentration is also examined by a dynamic adsorption processes. The detectable concentration limit of streptavidin within 3000 s in the detection system is expected from the signal‐to‐noise to be less than 150 pM.
Bio/Abiotic Interface Constructed from Nanoscale DNA Dendrimer and Conducting Polymer for Ultrasensitive Biomolecular Diagnosis
Authors: Wei Fang , Liao Wei , Xu Zheng , Yang Yang , Wong David T. , Ho Chih‐Ming
Published: April 2009

For sensors detecting immobilized biomarkers, the interface between the surface and the fluid medium plays an important role in determining the levels of signal and noise in the electrochemical detection process. When protein is directly immobilized on the metal electrode, denaturation of the protein by surface–protein interaction results in low activity and low signal level. A conducting polymer‐based interface can prevent the protein conformation change and alleviate this problem. A DNA dendrimer is introduced into the interfacial film on the sensor surface to further improve the sensor performance. DNA dendrimer is a nanoscale dendrite constructed of short DNA sequences, which can be easily incorporated into the abiotic conducting polymer matrix and is biocompatible with most biological species. In this work, DNA dendrimer and polypyrrole (DDPpy) form the bio/abiotic interface on electrochemical sensors. Detection of two salivary protein markers (IL‐8 and IL‐1β) and one mRNA salivary marker (IL‐8) is used to demonstrate the efficiency of the DDPpy sensor. A limit of detection (LOD) of protein of 100–200 fg mL−1 is achieved, which is three orders of magnitude better than that without the DNA dendrimer interface. An LOD of 10 aM is established for IL‐8 mRNA. The typical sample volume used in the detection is 4 µL, thus the LOD reaches only 25 target molecules (40 yoctomole).
Drug/Dye‐Loaded, Multifunctional Iron Oxide Nanoparticles for Combined Targeted Cancer Therapy and Dual Optical/Magnetic Resonance Imaging
Authors: Santra Santimukul , Kaittanis Charalambos , Grimm Jan , Perez J. Manuel
Published: April 2009

A biocompatible, multimodal, and theranostic functional iron oxide nanoparticle is synthesized using a novel water‐based method and exerts excellent properties for targeted cancer therapy, and optical and magnetic resonance imaging. For the first time, a facile, modified solvent diffusion method is used for the co‐encapsulation of both an anticancer drug and near‐infrared dyes. The resulting folate‐derivatized theranostics nanoparticles could allow for targeted optical/magnetic resonance imaging and targeted killing of folate‐expressing cancer cells.
Scoping software process lines
Authors: Armbrust Ove , Katahira Masafumi , Miyamoto Yuko , Münch Jürgen , Nakao Haruka , Ocampo Alexis
Published: April 2009

Defining organization‐specific process standards by integrating, harmonizing, and standardizing heterogeneous and often implicit processes is an important task, especially for large development organizations. On the one hand, such a standard must be generic enough to cover all of the organization's development activities; on the other hand, it must be as detailed and precise as possible to support employees' daily work. Today, organizations typically maintain and advance a plethora of individual processes, each addressing specific problems. This requires enormous effort, which could be spent more efficiently. This article introduces an approach for developing a Software Process Line that, similar to a Software Product Line, promises to reduce the complexity and thus, the effort required for managing the processes of a software organization. We propose Scoping, Modeling, and Architecting the Software Process Line as major steps, and describe in detail the Scoping approach we recommend, based on an analysis of the potential products to be produced in the future, the projects expected in the future, and the respective process capabilities needed. In addition, the article sketches experience from determining the scope of space process standards for satellite software development. Finally, it discusses the approach, draws conclusions, and gives an outlook on future work. Copyright © 2009 John Wiley & Sons, Ltd.
Method engineering: towards methods as services
Authors: Rolland Colette
Published: April 2009

Method engineering has emerged as the result of the necessity to adapt methods to better fit the needs of the development task at hand. Its aim is to provide techniques for retrieving reusable method components, adapting and assembling these together to form the new method. The paper provides a survey of the main results obtained for the two issues of defining and assembling components. It argues, thereafter, that the full power of method components can be widely exploited by moving to the notion of method services. The paper finally outlines a possible approach towards Method as a Service (MaaS), and illustrates it. Copyright © 2009 John Wiley & Sons, Ltd.
Improving the coverage criteria of UML state machines using data flow analysis
Authors: Briand Lionel , Labiche Y. , Lin Q.
Published: April 2009

A number of coverage criteria have been proposed for testing classes and class clusters modeled with state machines. Previous research has revealed their limitations in terms of their capability to detect faults. As these criteria can be considered to execute the control flow structure of the state machine, we are investigating how data flow information can be used to improve them in the context of UML state machines. More specifically, we investigate how such data flow analysis can be used to further refine the selection of a cost‐effective test suite among alternative, adequate test suites for a given state machine criterion. This paper presents a comprehensive methodology to perform data flow analysis of UML state machines—with a specific focus on identifying the data flow from OCL guard conditions and operation contracts—and applies it to a widely referenced coverage criterion, the round‐trip path (transition tree) criterion. It reports on two case studies whose results show that data flow information can be used to select the best transition tree, in terms of cost effectiveness, when more than one satisfies the transition tree criterion. The results also suggest that different trees are complementary in terms of the data flow that they exercise, thus, leading to the detection of intersecting but distinct subsets of faults. Copyright © 2009 John Wiley & Sons, Ltd.
International transfer pricing and subsidiary performance: The role of organizational justice
Authors: Paz‐Vega Ramón
Published: April 2009

International intrafirm trade is increasingly important in the global economy. Intrafirm transactions are governed by transfer‐pricing policies mandated by parent companies. Economic and accounting theories have long prescribed policies that maximize the parent company's short‐term profits but may have other, unintended outcomes. These outcomes are explored in a single‐case study. Based on this case study and organizational justice theory, a theoretical framework is developed to show how frequently used transfer‐pricing policies, through their impact on subsidiary managers' perceptions of justice, can significantly affect the subsidiary's strategic performance. First, the conditions under which transfer‐pricing policies can be perceived as procedurally, interactionally, or distributively unfair are presented. Second, it is proposed that those justice perceptions have an impact on subsidiary managers' commitment, trust in the parent company, neglect, ethical behavior, productivity, work quality, and compliance, and that the magnitude of this impact is moderated by the quality of relations between the parent company and subsidiary managers. Finally, it is predicted that such attitudes and behaviors may generate important agency and transaction costs that jeopardize the expected outcomes of international strategies of vertical integration. © 2009 Wiley Periodicals, Inc.
Descriptive and mechanistic toxicity of conazole fungicides using the model test alga Dunaliella tertiolecta (chlorophyceae)
Authors: Baird Thomas D. , DeLorenzo Marie E.
Published: April 2009

Conazole fungicides are commonly used to prevent fungal growth on turf grass and agricultural crops. As many of these sites are adjacent to coastal waterways and estuaries, there exists the potential for nontarget effects of runoff on marine organisms. This study reports 96 h EC50 values for four selected conazole fungicides (triadimefon = 5.98 mg/L; triadimenol = 5.51 mg/L; propiconazole = 2.33 mg/L; hexaconazole = 0.91 mg/L) to the model test alga Dunaliella tertiolecta. We further investigated possible mechanisms of toxicity by examining sublethal effects of exposure on cell morphology, osmoregulatory function, and lipid composition. These mechanistic studies revealed that conazole exposure does not inhibit synthesis of the cell's glycerol osmolyte, but does result in an overall increase in cellular volume and total lipid content. Both fungi and chlorophytes rely on ergosterol to maintain membrane structure and fluidity, and we provide evidence that the sterol‐inhibiting conazoles may interfere with ergosterol biosynthesis in the cell membrane of Dunaliella. These findings suggest that green algae may be especially susceptible to nontarget effects of sterol‐inhibiting fungicides in marine systems. Published 2009 by Wiley Periodicals, Inc. Environ Toxicol 2010
Wind turbine rotor‐tower interaction using an incompressible overset grid method
Authors: Zahle Frederik , Sørensen Niels N. , Johansen Jeppe
Published: April 2009

In this paper, 3D Navier–Stokes simulations of the unsteady flow over the NREL Phase VI turbine are presented. The computations are carried out using the structured grid, incompressible, finite volume flow solver EllipSys3D, which has been extended to include the use of overset grids. Computations are presented, firstly, on an isolated rotor, and secondly, on the downwind configuration of the turbine, which includes modelling of the rotor, tower and tunnel floor boundary.

The solver successfully captures the unsteady interaction between the rotor blades and the tower wake, and the computations are in good agreement with the experimental data available. The interaction between the rotor and the tower induces significant increases in the transient loads on the blades and is characterized by an instant deloading and subsequent reloading of the blade, associated with the velocity deficit in the wake, combined with the interaction with the shed vortices, which causes a strongly time‐varying response. Finally, the results show that the rotor has a strong effect on the tower shedding frequency, causing under certain flow conditions vortex lock‐in to take place on the upper part of the tower. Copyright © 2009 John Wiley & Sons, Ltd.
Individual blade pitch control of floating offshore wind turbines
Authors: Namik H. , Stol K.
Published: April 2009

Floating wind turbines offer a feasible solution for going further offshore into deeper waters. However, using a floating platform introduces additional motions that must be taken into account in the design stage. Therefore, the control system becomes an important component in controlling these motions. Several controllers have been developed specifically for floating wind turbines. Some controllers were designed to avoid structural resonance, while others were used to regulate rotor speed and platform pitching. The development of a periodic state space controller that utilizes individual blade pitching to improve power output and reduce platform motions in above rated wind speed region is presented. Individual blade pitching creates asymmetric aerodynamic loads in addition to the symmetric loads created by collective blade pitching to increase the platform restoring moments. Simulation results using a high‐fidelity non‐linear turbine model show that the individual blade pitch controller reduces power fluctuations, platform rolling rate and platform pitching rate by 44%, 39% and 43%, respectively, relative to a baseline controller (gain scheduled proportional–integral blade pitch controller) developed specifically for floating wind turbine systems. Turbine fatigue loads were also reduced; tower side–side fatigue loads were reduced by 39%. Copyright © 2009 John Wiley & Sons, Ltd.
Pentaorganosilicates
Authors: Couzijn Erik P. A. , Slootweg J. Chris , Ehlers Andreas W. , Lammertsma Koop
Published: April 2009

In this research report, we explore the emerging field of stable pentaorganosilicates, with the aim to show the development from transient species to stable and configurationally rigid analogues that may find application e.g. as novel chiral auxiliaries or in chiral ionic liquids.