bluuebunny/crossref_metadata_2025 huggingface dataset:
Rapid and efficient screening of adsorbent for oligopeptide using molecular docking and isothermal titration calorimetry
Authors: Qiao Yitao , Wei Zhong , Feng Jing , Chen Yingchao , Li Pinglin , Wang Wei , Ma Yi , Yuan Zhi
Published: June 2009

A rapid and efficient method based on molecular docking and isothermal titration calorimetry (ITC) was developed to identify effective adsorbents for the target peptide Ser‐Glu‐Ala‐Asp‐His (SEADH). Preliminary screening of five candidate adsorbents using molecular docking revealed that three suitable structures (A1, A2, and A3) either with or without coordination of Zn2+ should be effective. The three selected structures were then prepared and further screened by evaluating their affinities for the peptide SEADH using ITC. The screening results revealed that the adsorbent A2 coordinated with Zn2+ was the best adsorbent, and subsequent static adsorption experiments confirmed the reliability of the screening method. Further ITC analysis, combined with molecular docking, was performed to provide the possible adsorption mechanism.
Capillary zone electrophoresis with field enhanced sample stacking as a tool for targeted metabolome analysis of adenine nucleotides and coenzymes in Paracoccus denitrificans
Authors: Musilová Jindra , Sedláček Vojtěch , Kučera Igor , Glatz Zdeněk
Published: June 2009

The main aim of this work was to demonstrate the applicability of capillary zone electrophoresis in combination with field enhanced sample stacking in targeted metabolome analyses of adenine nucleotides – AMP, ADP, ATP, coenzymes NAD+, NADP+ and their reduced forms in Paracoccus denitrificans. Sodium carbonate/hydrogencarbonate buffer (100 mM, pH 9.6) with the addition of β‐CD at a concentration of 10 mM was found to be an effective BGE for their separation within 20 min. Besides this, special attention was paid to the development of the procedure for the extraction of specific metabolites from the bacterium P. denitrificans. This procedure was not only optimised to achieve the highest metabolite yields but also to obtain a sample that was fully compatible with the online preconcetration strategy used. The developed methodology was finally applied in a study of the bacterium P. denitrificans at various stages of the active respiratory chain.
Endoscopic repair of laryngeal cleft type I and type II: When and why?
Authors: Rahbar Reza , Chen Judy L. , Rosen Rachel L. , Lowry Kristen C. , Simon Dawn M. , Perez Jennifer A. , Buonomo Carlo , Ferrari Lynne R. , Katz Eliot S.
Published: June 2009

Objectives/Hypothesis:

To evaluate the clinical features of children with type I and type II laryngeal cleft and the role of conservative monitoring versus endoscopic repair in their management.

Methods:

Clinical presentation and evaluation; findings at the time of laryngoscopy, bronchoscopy, and esophagoscopy; and efficacy and outcome of conservative monitoring and endoscopic CO2 laser repair.

Results:

Eighty‐one patients were evaluated for aspiration. Seventy‐four patients were diagnosed as having a clinically significant laryngeal cleft. Thirty‐two patients (14 males, 18 females) were monitored conservatively. Forty‐nine patients (26 males, 23 females) required surgical intervention due to failed medical and feeding therapy of aspiration related to their laryngeal clefts (28 type I, 21 type II). Endoscopic CO2 laser repair was used in all these patients.

Conclusions:

Medical and feeding therapy should be the first modality of treatment in patients with laryngeal cleft type I and type II. Factors supporting surgical repair include: 1) clinically apparent aspiration with feeding, 2) severity of pulmonary status, 3) findings on modified barium swallow and chest x‐ray, 4) absence of significant comorbid conditions predisposing to aspiration, 5) findings on upper aerodigestive endoscopy, and 6) poor response to medical management and feeding therapy. Laryngoscope, 2009
Evaluation of hand circulation before radial forearm free flap surgery
Authors: Khan Afroze S. , Henton John M. D. , Adams Titus S. T. , Dwivedi Raghav C. , Harris Paul A.
Published: June 2009

The radial forearm free flap (RFFF) is a versatile flap offering many reconstructive options for head and neck defects. Its low bulk, ease of dissection, and excellent vascularity are among its advantages. Its low flap loss and complication rates offer the best choice for the reconstruction of oral, oropharyngeal, and hypopharyngeal lining. Evaluation of collateral circulation to the hand is important to avoid distal ischemia and donor site morbidity. Pulse oximetry can be used to augment Allen's test to assess collateral supply to the hand. This cost‐neutral technique can be used in routine preoperative screening prior to RFFF surgery. Laryngoscope, 2009
An underreported complication of laryngeal microdebrider: Vocal fold web and granuloma: A case report
Authors: Mortensen Melissa , Woo Peak
Published: June 2009

Objectives/Hypothesis:

The microdebrider has become a valuable instrument for otolaryngologists. It is now used in the larynx for treatment of recurrent respiratory papillomatosis, laryngeal stenosis, and debridement of large cancers for airway control. There are few reported complications reported with the use of the microdebrider in the larynx.

Study Design:

A case report.

Methods:

A patient with a vocal fold polyp underwent removal of the polyp with a microdebrider at an outside institution. He presented to our clinic 2 months after the excision with a severely strained near aphonic voice. On rigid stroboscopic examination we saw a large anterior commisure laryngeal web with a granuloma. This was repaired by granuloma excision, web lysis, buccal graft, and laryngeal stent placement.

Conclusions:

The microdebrider is an extremely valuable tool for the otolaryngologist. Violation of the epithelium and the lamina propria with muscle exposure can result in serious damage to the vocal folds. When using powered instrumentation the surgeon should use the upmost caution in the larynx to avoid causing debilitating injury and scar with subsequent dysphonia. Laryngoscope, 2009
Differentiating between adductor and abductor spasmodic dysphonia using airflow interruption
Authors: Hoffman Matthew R. , Jiang Jack J. , Rieves Adam L. , McElveen Kelsey A. B. , Ford Charles N.
Published: June 2009

Objectives/Hypothesis:

To measure the laryngeal resistance (RL), subglottal pressure (Ps), and mean flow rate (MFR) of adductor (ADSD) and abductor (ABSD) spasmodic dysphonia patients using the airflow interrupter.

Methods:

The RL of six ABSD and seven ADSD patients was measured using the airflow interrupter, a noninvasive device designed to measure MFR and Ps via mechanical balloon valve interruption. Subjects performed 10 trials at each of two intensity levels, with each trial consisting of a sustained /a/ during which phonation was interrupted for 500 ms. Laryngeal resistance was calculated as subglottal pressure divided by airflow.

Results:

Mean RL for the ADSD and ABSD subtypes at 65 dB were 24.78 cmH2O/L/s and 14.51 cmH2O/L/s, respectively (P = .04). Mean RL at 70 dB were 40.02 cmH2O/L/s and 15.84 cmH2O/L/s (P = .014). Ps for the ADSD and ABSD subtypes at 65 dB were 10.23 cmH2O and 8.32 cmH2O, respectively (P = .582). At the 70 dB level, Ps were 12.39 cmH2O and 11.78 cmH2O (P = .886). MFR for the ADSD and ABSD subtypes at 65 dB were 435 mL/s and 746 mL/s (P = .205). Mean MFR at 70 dB were 518 mL/s and 848 mL/s (P = .198).

Conclusions:

Noninvasive measurements of RL may be useful for differentiating between ADSD and ABSD. This simple objective test, which produces a quantitative output, could be used to evaluate laryngeal function in patients with spasmodic dysphonia. Laryngoscope, 2009
Some convexity properties of Dirichlet series with positive terms
Authors: Cerone Pietro , Dragomir Sever S.
Published: June 2009

Some basic results for Dirichlet series ψ with positive terms via log‐convexity properties are pointed out. Applications for Zeta, Lambda and Eta functions are considered. The concavity of the function 1/ψ is explored and, as a main result, it is proved that the function 1/ζ is concave on (ζ–1(e), ∞). As a consequence of this fundamental result it is noted that Zeta at the odd positive integers is bounded above by the harmonic mean of its immediate even Zeta values which are known explicitly (© 2009 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Semilinear Schrödinger equation with time dependent coefficients
Authors: Fanelli Luca
Published: June 2009

In this paper we study local and global well‐posedness in L2 and H1 of the Cauchy problem for the following nonlinear Schrödinger equations
equation image
in the space ℝ1+n , with n ≥ 2. The coefficient a (t) is assumed to be positive, and possibly vanishing with finite order on a discrete set; we find the relationship between the critical powers γ for the well‐posedness and the order of the zeroes of a (© 2009 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Global attractor in competitive Lotka–Volterra systems
Authors: Hou Zhanyuan
Published: June 2009

For autonomous Lotka–Volterra systems of differential equations modelling the dynamics of n competing species, new criteria are established for the existence of a single point global attractor. Under the conditions of these criteria, some of the species will survive and stabilise at a steady state whereas the others, if any, will die out (© 2009 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Calcium isotope analysis by mass spectrometry
Authors: Boulyga Sergei F.
Published: June 2009

The variations in the isotopic composition of calcium caused by fractionation in heterogeneous systems and by nuclear reactions can provide insight into numerous biological, geological, and cosmic processes, and therefore isotopic analysis finds a wide spectrum of applications in cosmo‐ and geochemistry, paleoclimatic, nutritional, and biomedical studies. The measurement of calcium isotopic abundances in natural samples has challenged the analysts for more than three decades. Practically all Ca isotopes suffer from significant isobaric interferences, whereas low‐abundant isotopes can be particularly affected by neighboring major isotopes. The extent of natural variations of stable isotopes appears to be relatively limited, and highly precise techniques are required to resolve isotopic effects. Isotope fractionation during sample preparation and measurements and instrumental mass bias can significantly exceed small isotope abundance variations in samples, which have to be investigated. Not surprisingly, a TIMS procedure developed by Russell et al. (Russell et al., 1978. Geochim Cosmochim Acta 42: 1075–1090) for Ca isotope measurements was considered as revolutionary for isotopic measurements in general, and that approach is used nowadays (with small modifications) for practically all isotopic systems and with different mass spectrometric techniques. Nevertheless, despite several decades of calcium research and corresponding development of mass spectrometers, the available precision and accuracy is still not always sufficient to achieve the challenging goals. The present article discusses figures of merits of presently used analytical methods and instrumentation, and attempts to critically assess their limitations. In Sections 2 and 3, mass spectrometric methods applied to precise stable isotope analysis and to the determination of 41Ca are described. Section 4 contains a short summary of selected applications, and includes tracer experiments and the potential use of biological isotope fractionation in medical studies, paleoclimatic and paleoceanographic, and other terrestrial as well as extraterrestrial investigations. © 2009 Wiley Periodicals, Inc., Mass Spec Rev 29:685–716, 2010
Epigenetic inactivation of Homeobox A5 gene in nonsmall cell lung cancer and its relationship with clinicopathological features
Authors: Kim Dong‐Sun , Kim Min‐Jin , Lee Ji‐Yun , Lee Su‐Man , Choi Jun‐Young , Yoon Ghil‐Suk , Na Yeon‐Kyung , Hong Hae‐Sook , Kim Sang‐Geol , Choi Jin‐Eun , Lee Shin‐Yeop , Park Jae‐Yong
Published: June 2009

Promoter methylation is an important mechanism in gene silencing and is a key epigenetic event in cancer development. Homeobox A5 (HOXA5) is a master regulator of the morphogenesis and cell differentiation to be implicated as a tumor suppressor gene in breast cancer, but its role in lung cancer is still unknown. In this study, we have investigated the methylation status of the promoter region of the HOXA5 gene in nonsmall cell lung cancers (NSCLCs) using nested and standard methylation‐specific PCR (MSP) and correlated the methylation status with clinicopathological features. With standard MSP analysis, HOXA5 methylation were found in 113 (81.3%) of 139 NSCLCs and 72 (51.8%) in their corresponding nonmalignant lung tissues. RT‐PCR and immunohistochemical analysis showed that HOXA5 methylation correlates with gene expression. Moreover, in the patients with stage I disease, HOXA5 methylation was more frequent in smokers than in never‐smokes (P = 0.01). There was no influence of HOXA5 methylation on survival in all NSCLCs or at stages II–IV. However, in the patients with stage I disease, HOXA5 methylation was associated with a borderline significantly worse survival (P = 0.09). These findings suggest that downregulation of the HOXA5 gene by aberrant promoter methylation occurs in the vast majority of NSCLCs and that it may play a role in the pathogenesis of NSCLC. Additional studies with larger sample sizes are required to evaluate the prognostic value of HOXA5 methylation in patients with stage I NSCLC. © 2009 Wiley‐Liss, Inc.
A comparison of metabolite extraction strategies for 1H‐NMR‐based metabolic profiling using mature leaf tissue from the model plant Arabidopsis thaliana
Authors: Kaiser Kayla A. , Barding Gregory A. , Larive Cynthia K.
Published: June 2009

Metabolite analysis is recognized as an important facet of systems biology, however complete metabolome characterization has not been realized due to challenges in sample preparation, inherent instrumental limitations and the labor intensive task of data interpretation. This work aims to compare several commonly used metabolite extraction strategies for their effect on the 1H nuclear magnetic resonance (NMR) metabolic profile of extracts of the model plant Arabidopsis thaliana. Extractions were carried out on aliquots from a pool of homogenized plant tissue using CD3CN/D2O, buffered D2O, perchloric acid in D2O, CD3OD/D2O and CD3OD/D2O/CDCl3 as the extraction solvents. The effects of lyophilization as a sample pretreatment, solvent evaporation and extract fractionation for removal of interfering species were studied. Representative spectra are presented for qualitative interpretation. Analytical reproducibility was evaluated by principal components analysis. Perchloric acid facilitated acid‐catalyzed cleavage of sucrose, further complicating biological interpretation of the resulting metabolite profile. The solvent system CD3OD/D2O/CDCl3 gave the least reproducible results in our hands. D2O extracts suffered from poor stability probably due to contamination by soluble enzymes, which were not denatured in this solvent. CD3CN/D2O extracts showed greater stability than D2O alone, but problems were encountered due to degradation of 1H NMR spectral resolution during lengthy acquisitions due to partial phase separation. In addition, this solvent system produced spectra with significant contamination by lipids that obscured spectral regions containing the resonances of the aliphatic amino acids. These problems were solved by speedvacuuming the CD3CN/D2O extract and reconstituting in D2O solution. Copyright © 2009 John Wiley & Sons, Ltd.
High‐Molecular‐Weight Poly(tert‐butyl acrylate) by Nitroxide‐Mediated Polymerization: Effect of Chain Transfer to Solvent
Authors: Lessard Benoît , Tervo Christopher , Marić Milan
Published: June 2009

Tert‐Butyl acrylate (TBA) was polymerized by nitroxide‐mediated polymerization (NMP) using BlocBuilder initiator and 4.5 mol‐% additional SG1 (N‐tert‐butyl‐N‐[1‐diethylphosphono‐(2,2‐dimethylpropyl)] nitroxide) relative to BlocBuilder (2‐methyl‐2‐[N‐tert‐butyl‐N‐(diethoxylphosphoryl‐2,2‐(dimethylpropyl)aminooxy]propionic acid) at 115 °C in bulk and in various solvents. In all cases, number average molecular weight ($\overline M _{\rm n}$) increased linearly up to 35% conversion. kpK values (kp = propagation rate constant, K = equilibrium constant) for TBA agreed well with literature data. For higher target $\overline M _{\rm n}$ > 50 kg · mol−1, solution polymerizations used to reduce viscosity were problematic as chain transfer reactions became noticeable, particularly when block copolymers with styrene were desired. A better strategy to obtain high $\overline M _{\rm n}$ block copolymers involved a semi‐batch feeding in bulk of styrene monomer to a poly(TBA) macroinitiator which resulted in high $\overline M _{\rm n}$ gradient blocks with low polydispersity ($\overline M _{\rm n}$ = 54.7 kg · mol−1, $\overline M _{\rm w} /\overline M _{\rm n}$ = 1.3).

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Non‐convex dual forms based on exponential intervening variables, with application to weight minimization
Authors: Wood Derren W. , Groenwold Albert A.
Published: June 2009

We study the weight minimization problem in a dual setting. We propose new dual formulations for non‐linear multipoint approximations with diagonal approximate Hessian matrices, which derive from separable series expansions in terms of exponential intervening variables. These, generally, nonconvex approximations are formulated in terms of intervening variables with negative exponents, and are therefore applicable to the solution of the weight minimization problem in a sequential approximate optimization (SAO) framework.

Problems in structural optimization are traditionally solved using SAO algorithms, like the method of moving asymptotes, which require the approximate subproblems to be strictly convex. Hence, during solution, the nonconvex problems are approximated using convex functions, and this process may in general be inefficient. We argue, based on Falk's definition of the dual, that it is possible to base the dual formulation on nonconvex approximations. To this end we reintroduce a nonconvex approach to the weight minimization problem originally due to Fleury, and we explore certain convex and nonconvex forms for subproblems derived from the exponential approximations by the application of various methods of mixed variables. We show in each case that the dual is well defined for the form concerned, which may consequently be of use to the future code developers. Copyright © 2009 John Wiley & Sons, Ltd.
Potential particles for the modelling of interlocking media in three dimensions
Authors: Harkness J.
Published: June 2009

A method is presented for the model creation and dynamic analysis of three‐dimensional interlocking media, such as locked sands or dry stone walls, in DEM simulations. A new form of discrete element is developed for this purpose, based on the concept of potential particles. A potential function is proposed for the modelling of spheres truncated by flats, and the mechanics of contacting particles is examined in some detail. In addition, suggestions are made to improve the convergence of the solver and accuracy of the solution for the contact point. Finally, some examples are presented, including a simulation of interlocked particles in a periodic shearbox. Copyright © 2009 John Wiley & Sons, Ltd.
Unilateral and bilateral upper extremity weight‐bearing effect on upper extremity impairment and functional performance after brain injury
Authors: Reistetter Timothy , Abreu Beatriz C. , Bear‐Lehman Jane , Ottenbacher Kenneth J.
Published: June 2009

The purpose of the study was to investigate the effect of upper extremity (UE) weight bearing on UE impairment functional performance of persons with acquired brain injury (BI).

A quasi‐experimental design was used to examine a convenience sample of 99 persons with acquired BI and 22 without BI (WBI) living in a community re‐entry centre. A computerized force‐sensing array pressure map system was used to determine the UE pressure during unilateral and bilateral conditions. Differences between groups were examined using t‐tests. Correlations were computed between UE weight bearing and hand function, and functional performance as measured by the Fugl‐Meyer scale and functional independence measure (FIM) scale.

The group of people with BI exerted significantly lower UE weight bearing during unilateral conditions as compared with persons WBI [left: t (119) = 2.34, p = 0.021; right: t (119) = 4.79, p = 0.043). UE weight‐bearing measures correlated strongly with FIM motor scores with bilateral UE conditions yielded the highest significant correlation (bilateral left r = 0.487, p < 0.001; bilateral right r = 0.469, p < 0.01).

The results indicated that UE weight‐bearing pressure differs in unilateral and bilateral conditions, between persons with and WBI and between persons with stroke and traumatic brain injury. These findings may have implications for occupational therapists that use unilateral versus bilateral motor training for rehabilitation.

There is a need to replicate the study design with a randomized and stratified sample of persons with BI. Copyright © 2009 John Wiley & Sons, Ltd.
NSAID use and risk of leukaemia: a population‐based case‐control study
Authors: Bhayat F. , Das‐Gupta E. , Smith C. , Hubbard R.
Published: June 2009

Purpose

The use of non‐steroidal anti‐inflammatory drugs (NSAIDs) is associated with a reduced risk of developing colorectal and lung cancer. Studies suggesting similar associations in leukaemia have been small and underpowered. We have conducted a large population‐based case‐control study to determine whether the use of NSAIDs is associated with a reduced risk of acute and chronic leukaemias, and whether their use has any impact on survival in these patients.

Methods

We identified all the incident cases of leukaemia in ‘The Health Improvement Network’ (THIN) general practice dataset, along with at least four matched controls per case. We used conditional logistic regression to determine odds ratios for NSAID prescription rates and the risk of developing several leukaemia sub‐types. We then used Cox regression to determine the association between NSAID prescription rate and risk of death in leukaemia. Hazard ratios were adjusted for gender, age at diagnosis, smoking status and Townsend Score.

Results

The risk of leukaemia overall appears to increase marginally with increased use of NSAIDs prior to diagnosis. This is not seen when individual leukaemia sub‐types are examined, however, except perhaps in CLL where patients who had received 2–5 prescriptions/year are 34% more likely to be diagnosed with CLL than those who had not had any NSAID prescriptions (O.R. 1.34, p = 0.03, 95% C.I. 1.02–1.74). There was no statistically significant association between exposure to NSAIDs prior to leukaemia diagnosis and survival.

Conclusion

The use of NSAIDs does not reduce the risk of developing leukaemia, nor do they improve survival. Copyright © 2009 John Wiley & Sons, Ltd.
Montelukast and psychiatric disorders in children
Authors: Wallerstedt Susanna M. , Brunlöf Gertrud , Sundström Anders , Eriksson Anna L.
Published: June 2009

Purpose

A signal has been raised concerning montelukast and adverse drug reactions (ADRs) in children. The purpose of the present study was to evaluate psychiatric ADRs during treatment with montelukast in children.

Methods

We analyzed all reports of psychiatric disorders during treatment with montelukast in children (<18 years) in the Swedish ADR database SWEDIS (1998–2007). The Bayesian Confidence Propagation Neural Network (BCPNN) method was used to screen for disproportional reporting rates of these reactions. An information component (IC) with a positive 95% lower confidence limit indicates a statistically significant disproportionality between the expected and the reported rate for a drug and an ADR.

Results

A total of 48 reports of psychiatric disorders in children during treatment with montelukast were found in SWEDIS. Reports appeared every year after registration. Psychiatric disorders reported more than once included nightmares (n = 15), unspecified anxiety (n = 11), aggressiveness (n = 11), sleep disorders (n = 10), insomnia (n = 3), irritability (n = 3), hallucination (n = 3), hyperactivity (n = 3), and personality disorder (n = 2). In 23 reports (48%), the child experiencing psychiatric ADRs was ≤3 years old. Time from exposure to ADR was indicated in 35 reports. In 28 of these (80%), the time from exposure to ADR was less than 1 week. A statistical signal for psychiatric disorders appeared in the fourth quarter of 1998 (three reports, IC‐value: 2.34, 95% lower confidence limit: 0.62).

Conclusions

Psychiatric ADRs can occur during montelukast treatment in children, indicating that attention to this is essential. Further studies are needed to establish the magnitude of the problem. Copyright © 2009 John Wiley & Sons, Ltd.
Parkinson's Disease Society research conference
Authors: Archibald Neil
Published: June 2009

Progress: Advancing Parkinson's Research, the Parkinson's Disease Society research conference dedicated to showcasing the work of young Parkinson's disease researchers, was held in York in November 2008, attracting nearly 200 delegates. Neil Archibald, Parkinson's Disease Society Research Fellow, reports on some of the highlights of the conference, including stem cell and gene therapy research, the role of Lewy bodies in dementia and the use of deep brain stimulation in the treatment of Parkinson's disease. Copyright © 2009 Wiley Interface Ltd
Self‐Lubricating W–S–C Nanocomposite Coatings
Authors: Polcar Tomas , Evaristo Manuel , Cavaleiro Albano
Published: June 2009

This paper is aimed on a perspective low‐friction coatings, the W–S–C system deposited by magnetron sputtering, which exhibits extremely low‐friction coefficient together with high‐load‐bearing capacity. Special attention has been paid to the analysis of the frictional and wear mechanisms under different operating conditions, such as the contact pressure, the air humidity, and the temperature. The formation of a thin self‐lubricating WS2 tribolayer, which was observed regardless on the sliding conditions, is the driving force for the promising frictional properties of the coatings.

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High Productive Deposited Mo Layers for Back Ohmic Contacts of Solar Cells
Authors: Heinß Jens‐Peter , Händel Frank , Meyer Toni , Würz Roland
Published: June 2009

In the paper, thin molybdenum (Mo) layers produced by magnetron sputtering [state of the art in production for photovoltaic applications (PV)] are compared with those produced by high‐rate electron beam (EB) deposition technology. Stainless steel and borofloat glass served as substrate materials. Mo layers deposited by DC‐magnetron sputtering were produced as a reference and investigated by analysis of structure and specific electrical resistance. Alternative layers prepared by high‐rate EB‐deposition with a rate up to 240 nm·s−1 were characterised by inquests of mechanical properties, sheet resistance and cell efficiency. A strong dependency of specific electrical resistance on residual gas conditions was determined. The specific electrical resistance dropped from 18 to 11 µΩ·cm. Compactness of Mo layers increased with implementation of plasma activation. The layer formation became denser and comparable to the magnetron sputtered Mo layers.
Development of Decorative and Corrosion Resistant Coatings for the Surface Refinement of Magnesium Alloys by Plasma‐based Methods
Authors: Hoche Holger , Groß Stefan , Foerster Rudolf , Schmidt Juergen , Adamitzki Wolfgang
Published: June 2009

This paper was amended in June 2013 because of a change of the author's names. The corrected author byline is presented on the last page of the pdf‐file.

Within the presented study, the economic potential of PVD‐coatings for the surface refinement and protection of Mg‐alloys is fully examined. The research includes the introduction of new pre‐treatment methods by plasma and chemical polishing, followed by corrosion‐inhibiting PVD‐coating based on TiMgAlN and thin decorative PVD‐finish‐film consisting of Nb. Anodic oxidation of the PVD‐finish film guarantees the full colour palette by interference effects. It will be shown that chemical and plasma polishing can be applied for the surface pre‐treatment of magnesium alloys. The TiMgAlN coated magnesium alloys withstand the 96 h salt spray test without any significant corrosion damage.
Pressure‐induced structural transitions in multi‐walled carbon nanotubes
Authors: Shima Hiroyuki , Sato Motohiro
Published: June 2009

We demonstrate a novel cross‐sectional deformation, called the radial corrugation, of multi‐walled carbon nanotubes (MWNTs) under hydrostatic pressure. Theoretical analyses based on the continuum elastic approximation have revealed that MWNTs consisting of more than ten concentric walls undergo elastic deformations at critical pressure $p_{\rm c} \simeq {\rm 1}\,{\rm GPa}$, above which the circular shape of the cross‐section becomes radially corrugated. Various corrugation modes have been observed by tuning the innermost tube diameter and the number of constituent walls, which is a direct consequence of the core–shell structure of MWNTs.

Cross‐sectional views of MWNT under high hydrostatic pressure: elliptic deformation with the mode index n = 2 (left), and radial corrugations with n = 5 (center), and n = 6 (right). The index n indicates the circumferential wave number of the deformed cross‐section.

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Stimulation of glucose uptake by triterpenoids from Weigela subsessilis
Authors: Lee Myung Sun , Thuong Phuong Thien
Published: June 2009

Four ursane‐type triterpenoids, corosolic acid (1), ilekudinol B (2), ursolic acid (3) and pomolic acid (4), were isolated from an EtOAc‐soluble extract of the leaves of Weigela subsessilis. These bioactive compounds were evaluated for their glucose uptake activity and produced moderate to strong enhancement both in basal‐ and insulin‐stimulated L6 muscle cells. In particular, corosolic acid exhibited the most potent activity, increasing uptake by basal‐ and insulin‐stimulated myotubes by 2.63‐ and 3.33‐fold, respectively; ilekudinol B produced 1.6‐ and 2.9‐fold, ursolic acid produced 1.84‐ and 2.64‐fold, and pomolic acid produced 1.6‐ and 2.8‐fold increases. No cytotoxicities were observed for corosolic acid, ursolic acid and ilekudinol B in myoblasts, while pomolic acid at doses of 25 and 50 µm reduced cell viability by 19% and 21.8% upon 24 h treatment and by 48.6% and 54.1% upon 48 h treatment, respectively. These results suggest that ursane‐type triterpenoids from W. subsessilis might enhance glucose uptake by acting as insulin mimics and as insulin sensitizers and that they could be useful as nontoxic diabetes treatment agents. Copyright © 2009 John Wiley & Sons, Ltd.
Sensitivity of a modelled life cycle of a mesoscale convective system to soil conditions over West Africa
Authors: Gantner Leonhard , Kalthoff Norbert
Published: June 2009

Cloud‐resolving real‐case simulations initialized with European Centre for Medium‐range Weather Forecasts (ECMWF) analysis data were performed to investigate the sensitivity of a mesoscale convective system (MCS) to soil properties. Four scenarios were investigated: original ECMWF soil moisture (MOI); ECMWF soil moisture reduced by 35% (CTRL), which better fits with the satellite observations; homogeneous soil type and soil moisture (HOM); and homogeneous soil type with a north–south oriented drier band of two degrees width (BAND).

Initiation of convection was observed in all experiments. The initiation area was characterised by very low convective inhibition (CIN) and high convective available potential energy (CAPE). The simulations showed some evidence that convection was initiated in the vicinity of orography and along soil moisture inhomogeneities. Except for the MOI run, MCSs developed in all experiments. In CTRL, a weakening of the system was observed when approaching an area with reduced total water content and enhanced CIN. In BAND, convection developed almost simultaneously in the original initiation area and inside the dry band, where convergence, generated by thermally‐induced circulation and supported by downward mixing of momentum from the African Easterly Jet, triggered convection. When the mature MCS approached the band from the east it weakened, caused by increasing CIN ahead of the band. Triggering of convection on this day was favoured by drier surfaces and/or soil moisture inhomogeneities, while a mature system weakened in the vicinity of a drier surface. Thus a positive feedback between soil moisture and convection existed for a mature system whereas a negative feedback was found for triggering of convection. Copyright © 2009 Royal Meteorological Society
Application of wavelet denoising to improve OFDM‐based signal detection and classification
Authors: Klein Randall W. , Temple Michael A. , Mendenhall Michael J.
Published: June 2009

The developmental emphasis on improving wireless access security through various OSI PHY layer mechanisms continues. This work investigates the exploitation of RF waveform features that are inherently unique to specific devices and that may be used for reliable device classification (manufacturer, model, or serial number). Emission classification is addressed here through detection, location, extraction, and exploitation of RF [fingerprints] to provide device‐specific identification. The most critical step in this process is burst detection which occurs prior to fingerprint extraction and classification. Previous variance trajectory (VT) work provided sensitivity analysis for burst detection capability and highlighted the need for more robust processing at lower signal‐to‐noise ratio (SNR). The work presented here introduces a dual‐tree complex wavelet transform (DT‐ℂWT) denoising process to augment and improve VT detection capability. The new method's performance is evaluated using the instantaneous amplitude responses of experimentally collected 802.11a OFDM signals at various SNRs. The impact of detection error on signal classification performance is then illustrated using extracted RF fingerprints and multiple discriminant analysis (MDA) with maximum likelihood (ML) classification. Relative to previous approaches, the DT‐ℂWT augmented process emerges as a better alternative at lower SNR and yields performance that is 34% closer (on average) to [perfect] burst location estimation performance. Copyright © 2009 John Wiley & Sons, Ltd.
eRIPP‐FS: Enforcing privacy and security in RFID
Authors: Conti Mauro , Di Pietro Roberto , Mancini Luigi V. , Spognardi Angelo
Published: June 2009

In RFID systems addressing security issues, many authentication techniques require the tag to keep some sort of synchronization with the reader. In particular, this is true in those proposals that leverage hash chains. When the reader and the tag get de‐synchronized, possibly by an attacker, this paves the way to several denial of service (DoS) attacks, as well as threatening privacy (e.g.,viathetiming attack). Even if de‐synchronization happens for non‐malicious causes, this event has a negative effect on performances (for instance, slowing down the authentication process).

In this paper, we provide a solution to cope with the de‐synchronization between the tag and the reader when hash chains are employed. In particular, our solution relies on mutual reader‐tag authentication, achievedviahash traversal and Merkle tree techniques. We show that this techniques applied to an existing security protocol for RFID systems, such as RIPP‐FS, make timing attacks hard to succeed. Moreover, the proposed solutions can be transparently and independently adopted by similar security protocols as well to thwart timing attack and/or to provide reader‐tag mutual authentication.

Finally, extensive simulations show that our proposal introduces a negligible overhead to recover de‐synchronization. Copyright © 2009 John Wiley & Sons, Ltd.
An end‐to‐end approach to secure routing in MANETs
Authors: Dabideen Stephen , Smith Bradley R. , Garcia‐Luna‐Aceves J. J.
Published: June 2009

Providing secure routing in mobile ad hoc networks (MANETs) is far more difficult than establishing secure routing in wired networks or static wireless networks. Node mobility and the relative scarcity of bandwidth render prior solutions ineffective. Solutions based on securing link or path information do not work well in MANETs because the dynamic nature of links requires extensive use of flooding to establish effective countermeasures. On the other hand, solutions based on hop‐by‐hop exchanges of distance information are easily compromised. Instead of trying to secure the ordering of nodes, we argue that secure routing in MANETs must be based on the end‐to‐end verification of physical‐path characteristics aided by the exploitation of path diversity to increase the probability of finding secure paths. We apply this approach to the design of the Secure Routing through Diversity and Verification (SRDV) protocol, a secure routing protocol that we show to be as efficient as unsecured on‐demand or proactive routing approaches in the absence of attacks. We prove that the countermeasures used in SRDV can defend against a variety of known attacks to routing protocols, including attacks involving collusion, and the fabrication and modification of routing packets. We also show the effectiveness of the end‐to‐end mechanisms via simulations. Copyright © 2009 John Wiley & Sons, Ltd.
Implementation of Global Software Development: a structured approach
Authors: Casey Valentine , Richardson Ita
Published: June 2009

The analysis of a 3‐year in‐depth case study on virtual team operation in a globally distributed software development resulted in the identification of ten key factors for Global Software Development (GSD). These ten factors have been utilised as the basis for the development of the GSD Implementation Model. The objective of the creation and presentation of this model is to provide a practical and systematic approach to address the key activities, infrastructure and support which are required to facilitate effective distributed software development. This approach is inspired by the IDEALsm model and divided into five specific phases which are classified as Initiating, Provisioning, Establishing, Managing and Leveraging. The goal of the Initiating phase is to clearly determine why, if and how the distributed development strategy is to be selected and undertaken. The implementation of the Provisioning phase is to ensure that the required infrastructure, processes and support to facilitate successful distributed software development are identified and put in place. The focus of the Establishing phase is to ensure that the development teams are effectively established. The Managing phase addresses the day‐to‐day requirements of operating efficiently in a distributed environment. The Leveraging phase concentrates on the need to ensure that the structures and procedures are in place so that lessons learned can be documented and leveraged in existing and future projects. Copyright © 2009 John Wiley & Sons, Ltd.
Managing knowledge for information system evolution: the MinimalEDoc methodology
Authors: Salvaneschi Paolo
Published: June 2009

The paper describes a proposed method (MinimalEDoc—Minimal Documents for Software Evolution) for managing the documents required during the evolution phase of information systems. The method applies a minimalist approach to the documentation and the concept of ‘Total Cost of Ownership’. It is composed of definitions, principles, a documental model, a management process and a supporting tool. Documents are classified according to document types ‘maps’, ‘aspects’, ‘components’ and ‘critical points’. For specific classes of applications, we can define reusable document schemes and patterns. The documents are organized into a common knowledge base subject to multiple views for different classes of users. The implementation technology is based on a wiki tool integrating external specialized CASE tools. The methodology is supported by an empirical case study involving the information system of a large retail company. Copyright © 2009 John Wiley & Sons, Ltd.
MPS.BR: a successful program for software process improvement in Brazil
Authors: Montoni Mariano Angel , Rocha Ana Regina , Weber Kival Chaves
Published: June 2009

Software process improvement implementation based on software process reference models and standards is a complex and long‐term endeavor that requires investment of large sums of money. These obstacles usually hinder organizations from implementing software process improvement successfully, especially for small and medium‐size enterprises that operate under strict financial resources. This paper describes the MPS.BR, a nationwide program for software process improvement in Brazilian organizations. The main goal of this initiative is to develop and disseminate a Brazilian software process model (named MPS Model) aiming to establish a feasible pathway for organizations to achieve benefits from implementing software process improvement at reasonable costs, especially small and medium‐size enterprises. This paper presents the main components of the MPS Model and discusses the strategy executed to establish and maintain a community of MPS Model practitioners. The results of MPS Model adoption and dissemination in Brazilian software industry are also presented in this paper. Copyright © 2009 John Wiley & Sons, Ltd.
Integrated Automotive SPICE and safety assessments
Authors: Messnarz Richard , Ross Hans‐Leo , Habel Stephan , König Frank , Koundoussi Abdelhadi , Unterrreitmayer Jürgen , Ekert Damjan
Published: June 2009

In 2005 Automotive SPICE (based on ISO 15504) has been published (see http://www.automotivespice.com) and used in major automotive firms world wide. In parallel the topic ‘Functional Safety’ became important due to changes in liability law and the development of IEC 61508 as an application and branch independent standard for functional safety. As a result, ISO WD 26262 a ISO draft for functional safety has been initiated classifying systems with ASIL (automotive safety integrity levels) levels and requiring additional processes, techniques, and methods to illustrate the competence for managing systems that have an impact on the loss of lives.

An Automotive SPICE assessment usually takes (for the processes defined in the scope of the German automotive manufacturing association) 4 days per project. Adding the scope of a safety assessment this dramatically increases the number of hours used in assessments. In a working group of major automotive suppliers and assessment tool suppliers, we developed from 2005 to 2009 an integrated assessment approach. Portals in the above‐mentioned automotive suppliers already use this environment.

The working group that elaborated the methods and tools described in this paper are part of the SOQRATES initiative (http://www.soqrates.de) where more than 20 leading German firms collaborate in cross‐company task forces.

In this paper, we want to explain the results of the analysis done, the assessment model applied, and what kind of reports the integrated assessment environment is producing. The results of all work (except of the proprietary assessment tools) will be made public to all suppliers in 2009. Copyright © 2009 John Wiley & Sons, Ltd.
Genetic Basis of Inherited Macular Dystrophies and Implications for Stem Cell Therapy
Authors: Mellough Carla B. , Steel David H.W. , Lako Majlinda
Published: June 2009

Untreatable hereditary macular dystrophy (HMD) presents a major burden to society in terms of the resulting patient disability and the cost to the healthcare provision system. HMD results in central vision loss in humans sufficiently severe for blind registration, and key issues in the development of therapeutic strategies to target these conditions are greater understanding of the causes of photoreceptor loss and the development of restorative procedures. More effective and precise analytical techniques coupled to the development of transgenic models of disease have led to a prolific growth in the identification and our understanding of the genetic mutations that underly HMD. Recent successes in driving differentiation of pluripotent cells towards specific somatic lineages have led to the development of more efficient protocols that can yield enriched populations of a desired phenotype. Retinal pigmented epithelial cells and photoreceptors derived from these are some of the most promising cells that may soon be used in the treatment of specific HMD, especially since rapid developments in the field of induced pluripotency have now set the stage for the production of patient-derived stem cells that overcome the ethical and methodological issues surrounding the use of embryonic derivatives. In this review we highlight a selection of HMD which appear suitable candidates for combinatorial restorative therapy, focusing specifically on where those photoreceptor loss occurs. This technology, along with increased genetic screening, opens up an entirely new pathway to restore vision in patients affected by HMD.

Disclosure of potential conflicts of interest is found at the end of this article.
Cross‐cultural management and organizational behavior in Africa
Authors: Amoako‐Agyei Erika
Published: June 2009

For Western operations to succeed in Africa, foreign executives must embrace cross‐cultural management skills as part of a broad strategic focus. This article examines culture as the crucial dimension to forging strong social, economic, and diplomatic ties between Africa and the Western world. To globalize successfully into the African marketplace, the effective cross‐cultural manager must have an in‐depth understanding of the African cultural value system. By analyzing African conventions, whose norms differ greatly from Western culture, this article clarifies the key roles that African culture plays in management methods, organizational behavior, and business practices in the sub‐Saharan region. © 2009 Wiley Periodicals, Inc.
Protective incubators and South African MNEs
Authors: Klein Saul , Wöcke Albert
Published: June 2009

Emerging‐market multinational enterprises (MNEs) often lack conventional competitive advantages (high knowledge bases, stable currencies, industry concentrations of foreign direct investment) and, thus, should be disadvantaged in competing globally. A protective environment, however, may help develop firm‐specific advantages in countries with deficiencies in human capital, and market and technological resources. We demonstrate how four such companies from South Africa progressed from their domestic base to become successful MNEs. Contrary to expectations, international expansion of MNEs from less competitive economies may be driven more by the transfer of intangible knowledge across national boundaries than by exporting finished goods. © 2009 Wiley Periodicals, Inc.