bluuebunny/crossref_metadata_2025 huggingface dataset:
Cross‐cultural validation of a Patient Satisfaction with Interpersonal Relationship with Navigator measure: a multi‐site patient navigation research study
Authors: Jean‐Pierre Pascal , Fiscella Kevin , Winters Paul C. , Paskett Electra , Wells Kristen , Battaglia Tracy ,   The Patient Navigation Research Program Group
Published: July 2011

Background

Patient navigators are trained to help patients effectively access and use healthcare resources in order to facilitate timely completion of recommended cancer screening, diagnostic care, and treatment. Patient navigators provide logistic, instrumental, and psychosocial support to cancer patients. Yet few studies have examined patient–navigator relationships, particularly for Spanish‐speaking patients with low English proficiency. We aimed to validate a Spanish version of the Patient Satisfaction with Interpersonal Relationship with Navigator (PSN‐I‐Sp) scale.

Methods

We translated and back‐translated the PSN‐I into Spanish and administered the resulting PSN‐I‐Sp to 222 Spanish‐fluent participants. We conducted a principal components analysis and assessed Cronbach's coefficient alpha (α) to evaluate the latent structure and the internal consistency of the PSN‐I‐Sp. We also completed correlation analyses to examine divergence and convergence of the PSN‐I‐Sp with the Spanish version of the Patient Satisfaction with Cancer‐Related Care (PSCC‐Sp) and the patients' demographics.

Results

The principal components analysis revealed a one‐dimensional PSN‐I‐Sp measure that explained 82.0% of the variance. The reliability assessment revealed high internal consistency (α = 0.97). The PSN‐I‐Sp demonstrated good face validity and adequate convergent and divergent characteristics as indicated by a moderate correlation with scores on the PSCC‐Sp (all ps < 0.0001) and a non‐statistically significant correlation with marital status (all p > 0.05).

Conclusion

The PSN‐I‐Sp is a valid and internally consistent measure of satisfaction with interpersonal relationship with a patient navigator for Spanish‐speaking participants. Copyright © 2011 John Wiley & Sons, Ltd.
GC‐MS Investigation of Hexamethyldisiloxane–Oxygen Fed Cold Plasmas: Low Pressure Versus Atmospheric Pressure Operation
Authors: Fanelli Fiorenza , d'Agostino Riccardo , Fracassi Francesco
Published: June 2011

This study deals with the investigation by means of gas chromatography‐mass spectrometry (GC‐MS) of the exhaust gas of an rf low pressure (LP) glow discharge and of an atmospheric pressure (AP) FDBD fed with hexamethyldisiloxane (HMDSO), O2, and Ar. The influence of feed composition on monomer depletion and on the qualitative–quantitative distribution of stable by‐products formed by recombination of plasma intermediates is investigated. Without O2 addition to the feed almost comparable values of HMDSO depletion are observed both at low and AP. Oxygen addition does not influence the monomer depletion at LP while it induces a slight decrease of the depletion at AP. Whatever the working pressure, O2 controls the overall chemistry of the plasma, since it influences the concentration of by‐products (e.g., silanes, silanols, linear, and cyclic methylsiloxanes). At AP evidences of the importance of methyl abstraction from HMDSO molecule have been obtained, while at LP the prevalence of Si–O bond rupture, of fragmentation, and oligomerization reactions is observed. The comparison of results from the GC‐MS investigation of the exhaust gas with FT‐IR spectra of the deposited coatings allows to enhance hypotheses on the formation of silanols in the gas phase and in the deposit.

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PLP‐dependent enzymes as entry and exit gates of sphingolipid metabolism
Authors: Bourquin Florence , Capitani Guido , Grütter Markus Gerhard
Published: June 2011

Sphingolipids are membrane constituents as well as signaling molecules involved in many essential cellular processes. Serine palmitoyltransferase (SPT) and sphingosine‐1‐phosphate lyase (SPL), both PLP (pyridoxal 5′‐phosphate)‐dependent enzymes, function as entry and exit gates of the sphingolipid metabolism. SPT catalyzes the condensation of serine and a fatty acid into 3‐keto‐dihydrosphingosine, whereas SPL degrades sphingosine‐1‐phosphate (S1P) into phosphoethanolamine and a long‐chain aldehyde. The recently solved X‐ray structures of prokaryotic homologs of SPT and SPL combined with functional studies provide insight into the structure–function relationship of the two enzymes. Despite carrying out different reactions, the two enzymes reveal striking similarities in the overall fold, topology, and residues crucial for activity. Unlike their eukaryotic counterparts, bacterial SPT and SPL lack a transmembrane helix, making them targets of choice for biochemical characterization because the use of detergents can be avoided. Both human enzymes are linked to severe diseases or disorders and might therefore serve as targets for the development of therapeutics aiming at the modulation of their activity. This review gives an overview of the sphingolipid metabolism and of the available biochemical studies of prokaryotic SPT and SPL, and discusses the major similarities and differences to the corresponding eukaryotic enzymes.
Green fluorescent protein: A perspective
Authors: Remington S. James
Published: June 2011

A brief personal perspective is provided for green fluorescent protein (GFP), covering the period 1994–2011. The topics discussed are primarily those in which my research group has made a contribution and include structure and function of the GFP polypeptide, the mechanism of fluorescence emission, excited state protein transfer, the design of ratiometric fluorescent protein biosensors and an overview of the fluorescent proteins derived from coral reef animals. Structure‐function relationships in photoswitchable fluorescent proteins and nonfluorescent chromoproteins are also briefly covered.
Toxicities and sublethal effects of seven neonicotinoid insecticides on survival, growth and reproduction of imidacloprid‐resistant cotton aphid, Aphis gossypii
Authors: Shi XiaoBin , Jiang LiLi , Wang HongYan , Qiao Kang , Wang Dong , Wang KaiYun
Published: June 2011

BACKGROUND: Imidacloprid has been a major neonicotinoid insecticide for controlling Aphis gossypii (Glover) (Homoptera: Aphididae) and other piercing–sucking pests. However, the resistance to imidacloprid has been recorded in many target insects. At the same time, cross‐resistance of imidacloprid and other insecticides, especially neonicotinoid insecticides, has been detected.

RESULTS: Results showed that the level of cross‐resistance was different between imidacloprid and tested neonicotinoid insecticides (no cross‐resistance: dinotefuran, thiamethoxam and clothianidin; a 3.68–5.79‐fold cross‐resistance: acetamiprid, nitenpyram and thiacloprid). In the study of sublethal effects, imidacloprid at LC20 doses could suppress weight gain and honeydew excretion, but showed no significant effects on longevity and fecundity of the imidacloprid‐resistant cotton aphid, A. gossypii. However, other neonicotinoid insecticides showed significant adverse effects on biological characteristics (body weight, honeydew excretion, longevity and fecundity) in the order of dinotefuran > thiamethoxam and clothianidin > nitenpyram > thiacloprid and acetamiprid.

CONCLUSION: The results indicated that dinotefuran is the most effective insecticide for use against imidacloprid‐resistant A. gossypii. To avoid further resistance development, the use of nitenpyram, acetamiprid and thiacloprid should be avoided on imidacloprid‐resistant populations of A. gossypii. Copyright © 2011 Society of Chemical Industry
Development of a low‐density DNA microarray for diagnosis of target‐site mutations of pyrethroid and organophosphate resistance mutations in the whitefly Bemisia tabaci
Authors: Chung In‐Hyuk , Kang Soyoung , Kim Ye Rim , Kim Ji‐Hoon , Jung Jin Wook , Lee Seunghwan , Lee Si Hyeock , Hwang Seung Yong
Published: June 2011

BACKGROUND: Rapid and accurate detection of mutations related to insecticide resistance is essential for development of resistance management strategies to support sustainable agriculture. The M918V, L925I and T929V mutations of the voltage‐gated sodium channel gene (vgsc) and the F392W mutation of the acetylcholinesterase I gene (ace1) are reportedly associated with resistance to pyrethroids and organophosphates, respectively, in Bemisia tabaci. In order to detect known base substitutions in the ace1 and vgsc genes, a low‐density microarray with an allele‐specific probe was developed.

RESULTS: Specific regions of the ace1 and vgsc gene mutations were amplified by multiplex asymmetrical PCR using Cy3‐labelled primers, and then the PCR products were hybridised on the microarray. After analysing the probe signal data, the microarray containing 12 allele‐specific probes produced a unique pattern of probe signals for field DNA samples of B. tabaci. To determine the optimal cut‐off value of each probe, receiver operating characteristic (ROC) curve analysis was conducted using SPSS. Among 60 individual samples, microarray data for 57 samples were consistent with direct sequencing data.

CONCLUSION: Although many molecular detection methods have been employed to monitor insecticide resistance, the present microarray provides rapid and accurate identification of target mutations in B. tabaci for resistance management. Copyright © 2011 Society of Chemical Industry
Uncommon associations in target resistance among French populations of Myzus persicae from oilseed rape crops
Authors: Fontaine Séverine , Caddoux Laëtitia , Brazier Christine , Bertho Corentin , Bertolla Paul , Micoud Annie , Roy Lise
Published: June 2011

Within the framework of a molecular exploration of target resistance in populations of Myzus persicae on oilseed rapes in France, (1) the S431F mutation (coding gene ace2), although previously reckoned to be rare, revealed to be frequent, (2) M918L (phenotypically characterised) and L932F (both on para) were found for the first time in M. persicae, and (3) a linkage was revealed between M918L and S431F. While until recently populations developing on French oilseed rapes were dominated by genotypes possessing pyrethroid target resistance and esterase overproduction, to date a different type of dominating genotype, equipped with carbamate and pyrethroid target resistance, seems to be invading such fields. Copyright © 2011 Society of Chemical Industry
Triterpene saponins of Quillaja saponaria show strong aphicidal and deterrent activity against the pea aphid Acyrthosiphon pisum
Authors: De Geyter Ellen , Smagghe Guy , Rahbé Yvan , Geelen Danny
Published: June 2011

BACKGROUND: Saponins are a class of secondary plant metabolites consisting of a sugar moiety glycosidically linked to a hydrophobic aglycone (sapogenin) that often possess insecticidal activities. Four saponins were selected: two triterpene saponins, Q. saponaria saponins and aescin, and two steroidal saponins, digitonin and diosgenin. Their effects were investigated on an important pest species and a model piercing‐sucking insect, the pea aphid Acyrthosiphon pisum. The triterpene Q. saponaria saponins bark saponin received special attention because of its high activity. Aphids were challenged by oral and contact exposure to demonstrate aphicidal activities, and in choice experiments to support use as a natural deterrent.

RESULTS: When aphids were exposed to supplemented artificial diet for 3 days, a strong aphicidal activity was recorded for three of the four saponins, with an LC50 of 0.55 mg mL−1 for Q. saponaria saponins, 0.62 mg mL−1 for aescin and 0.45 mg mL−1 for digitonin. The LT50 values ranged between 1 and 4 days, depending on the dose. For diosgenin, only low toxicity (14%) was scored for concentrations up to 5 mg mL−1. In choice experiments with treated diet, a deterrence index of 0.97 was scored for Q. saponaria saponins at 1 mg mL−1. In contrast, direct contact showed no repellent effect. Spraying of faba bean plants with Q. saponaria saponins resulted in an LC50 of 8.2 mg mL−1. Finally, histological analysis in aphids fed with Q. saponaria saponins demonstrated strong aberrations of the aphid gut epithelium, and exposure of midgut CF‐203 cell lines to Q. saponaria saponins in vitro confirmed the cytotoxic effect.

CONCLUSIONS: The present insect experiments provide strong evidence that saponins, as tested here with triterpene Q. saponaria saponins, can be useful as natural aphicides and deterrents. Furthermore, the insect midgut epithelium is suggested to be a primary target of saponin activity.Copyright © 2011 Society of Chemical Industry
DFT studies of OH‐functionalized open‐ended zigzag, armchair, and chiral single wall carbon nanotubes
Authors: Chełmecka E. , Pasterny K. , Kupka T. , Stobiński L.
Published: June 2011

The functionalization of single‐wall carbon nanotubes (SWCNTs) by attaching various molecules or molecular groups to the exterior walls or tips has attracted much attention, because it offers a possible way to modify their electronic, chemical, optical and mechanical properties. In this contribution the results of DFT studies of pristine and OH‐modified open‐ended zigzag (9,0), armchair (5,5) and chiral (8,2) nanotubes are reported. The calculations have been performed for partially and fully functionalized at one end model SWCNTs with dangling bonds saturated with hydrogen atoms and a nonadditive dependence of attachment energy on the number of substituents was observed.
Structure, morphology, and aging of Ag–Fe dumbbell nanoparticles
Authors: Elsukova Anna , Li Zi‐An , Möller Christina , Spasova Marina , Acet Mehmet , Farle Michael , Kawasaki Masahiro , Ercius Peter , Duden Thomas
Published: June 2011

Dumbbell‐shaped or Janus‐type nanocomposites provide multifunctional properties with various diagnostic and therapeutic applications in biomedicine. We have prepared dumbbell Ag–Fe nanoparticles by magnetron sputtering with subsequent in‐flight annealing. Structural properties and chemical compositions of freshly prepared and 5‐month aged particles were examined by means of transmission electron microscopy including high‐resolution imaging, energy dispersive X‐ray spectroscopy, and 3D electron tomography. Fresh particles consist of a faceted Ag part on a Fe‐Fe3O4 composite particle of more spherical shape. Aging changes the crystallinity and morphology of the particles. The aged nanocomposite consists of a silver spherical particle that is attached to a hollow iron oxide sphere containing one or several silver clusters inside.

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TEM images of the fresh (a) and aged (b) Ag–Fe nanoparticles. (c) 3D reconstructed image of an aged Ag–Fe particle with color segmentation.
Minicrystallization in directionally solidified multicrystalline silicon and its effect on the photovoltaic properties of solar cells
Authors: Liu Bingfa , Chen Nan , Du Guoping , Liu Guihua , Li Yangsheng , Sun Wei , Rossetto Pietro
Published: June 2011

In this paper, we report the occurrence of minicrystallization in multicrystalline silicon ingots grown by the directional solidification method and its effect on the photovoltaic (PV) properties of multicrystalline silicon solar cells. Minicrystallization in multicrystalline silicon ingots sometimes occurs when the directional solidification process is not properly optimized, and it causes much smaller grain sizes in the minicrystallized regions. Serious shunting behaviour has been observed in multicrystalline silicon solar cells containing minicrystallized regions, and it is highly localized to these minicrystallized regions. Minicrystallization in multicrystalline silicon considerably deteriorates the overall PV properties of solar cells.
Formation of CuInSe2 from Cu2Se and In2Se3 compounds
Authors: Chen Daigao , Wang Deliang
Published: June 2011

Chalcopyrite α‐CuInSe2 (α‐CIS) was prepared from mixed powders of Cu2Se and In2Se3 by annealing in the Se‐ and the non‐Se environments. The mechanically ground powders were in an overall amorphous state. The mechanical alloying produced Cu3Se2 and CuSe compounds. At relatively low temperature, Cu3Se2 decomposed, Cu2−xSe and CuSe formed. The reaction for the formation of α‐CuInSe2 occurred essentially at a temperature at ∼350 °C in both the Se‐ and the non‐Se environments. In the non‐Se environment, reactions occurred by a solid–solid reaction and a certain amount of Se were released from the mixed powder, resulting in poor crystalline α‐CuInSe2 powders. When annealed in the Se environment, low‐melting Se‐rich Cu‐Se compounds were produced during reaction. The reactions occurred by a liquid–solid reaction above 450 °C. Large‐grained and good crystalline quality of chalcopyrite CIS with near stoichiometric atomic ratio was obtained above 450 °C.
The origin for increase of magnetic moment of Co in Co‐doped SnO2 with oxygen vacancies
Authors: Wang Hongxia , Zong Zhaocun , Li Peng , Yan Yu
Published: June 2011

In Co‐doped SnO2 fivefold degenerate Co‐3d states split into five singlet states. The magnetic moment of Co is mainly contributed by the spin polarization of Co‐dxy states. The introduction of oxygen vacancies largely increases the magnetic moment of Co. The increase of Co magnetic moment is caused by the conversion of spin–spin coupling between Co and its neighboring O atoms from antiparallel to parallel, which attributes to the hybridization and electrons transfer between oxygen vacancy impurity states and Co‐3d states.
Revisiting magnetism of capped Au and ZnO nanoparticles: Surface band structure and atomic orbital with giant magnetic moment
Authors: Hernando Antonio , Crespo Patricia , García Miguel Angel , Coey Michael , Ayuela Andrés , Echenique Pedro Miguel
Published: June 2011

In this article we review the exotic magnetism of nanoparticles (NPs) formed by substances that are not magnetic in bulk as described with generality in Section 1. In particular, the intrinsic character of the magnetism observed on capped Au and ZnO NPs is analysed. X‐ray magnetic circular dichroism (XMCD) analysis has shown that the magnetic moments are intrinsic and lie in the Au and Zn atoms, respectively, as analysed in Section 2, where the general theoretical ideas are also revisited. Since impurity atoms bonded to the surface act as donor or acceptor of electrons that occupy the surface states, the anomalous magnetic response is analysed in terms of the surface band in Section 3. Finally, Section 4 summarizes our last theoretical proposal.
Cholinesterases Inhibitory and Antioxidant Activities of Harpagophytum procumbens from In Vitro Systems
Authors: Georgiev Milen I. , Alipieva Kalina , Orhan Ilkay Erdogan
Published: July 2011

A previous report showed that extracts of cell suspension and transformed root cultures of Harpagophytum procumbens (commonly known as Devil's claw), an African plant with high medicinal value, exhibit strong antiinflammatory characteristics. The present work tests the ability of extracts, phenylethanoid‐containing fractions and the major phenylethanoid glycoside isolated from the Devil's claw cultures, to inhibit acetylcholinesterase and butyrylcholinesterase, and the antioxidant activity in iron‐related systems (e.g. ferric‐reducing antioxidant power and ferrous ion‐chelating capacity). The results indicated that the phenylethanoid fractions may be attractive for various commercial purposes since they displayed significant cholinesterase inhibitory activity (even higher than that of pure galanthamine in the case of butyrylcholinesterase inhibition assay). Crude methanolic extracts from cell and hairy root cultures of Devil's claw exhibited strong ferrous ion‐chelating capacity (1.5–2 times higher than pure butylated hydroxyanisole, used as positive standard). Copyright © 2011 John Wiley & Sons, Ltd.
Topical Application of Two Condensed Tannins from the Root of Rosa multiflora Thunberg for the Treatment of Atopic Dermatitis (AD) in NC/Nga Mice
Authors: Park Kwan Hee , Choi Sun Eun , Choi Young Wook , Lee Do Ik , Joo Seong Soo , Jeong Mi Sook , Bang Hyoweon , Lee Chung Soo , Lee Mi‐Kyung , Seo Seong Jun , Lee Min Won
Published: June 2011

Recently, the isolation of several condensed tannins from the roots of Rosa multiflora Thunberg, a traditional herbal therapy in oriental medicine for rheumatoid arthritis and scabies, was described. Two of the major condensed tannins – procyanidin B‐3 (ProB3) and ent‐guibourtinidol‐(4β → 6)‐catechin (RM‐1) – were then applied topically to atopic dermatitis‐like skin lesions on NC/Nga mice in order to assess their immunomodulatory properties. Both ProB3 and RM‐1 significantly reduced the serum levels of eosinophils, IgE and certain Th2 cytokines (IL‐4, 5 and 13) (p < 0.05 or 0.01). Additionally, ProB3 and RM‐1 significantly reduced both the mRNA and protein expression of COX‐2 and iNOS in mouse skin tissues (p < 0.01). Such results strongly suggest that ProB3 and RM‐1 may be useful in the treatment allergic skin conditions, most notably atopic dermatitis. Copyright © 2011 John Wiley & Sons, Ltd.
Theoretical study of the polymerization of p‐tert‐butyl‐anisol
Authors: Ayadi Sameh , Mignon Pierre , Abderrabba Manef , Chermette Henry
Published: June 2011

The stereoselective formation of dimers and trimers of p‐tert‐butyl‐anisol by electrochemical oxidation has been theoretically studied. For the purpose, density functional theory calculations with the PBE exchange‐correlation functional have been performed with a triple zeta plus polarization basis set. A mechanism has been proposed by validating one suggestion of the experimentalists, whereas other reaction pathways suggested by experimentalists have been ruled out. © 2011 Wiley Periodicals, Inc. Int J Quantum Chem, 2012
The classical‐map hyper‐netted‐chain (CHNC) method and associated novel density‐functional techniques for warm dense matter
Authors: Dharma‐Wardana M. W. C.
Published: June 2011

The advent of short‐pulse lasers, nanotechnology, as well as shock‐wave techniques have created new states of matter (e.g., warm dense matter) that call for new theoretical tools. Ion correlations, electron correlations, as well as bound states, continuum states, partial degeneracies and quasi‐equilibrium systems need to be addressed. Bogoliubov's ideas of timescales can be used to discuss the quasi‐thermodynamics of nonequilibrium systems. A rigorous approach to the associated many‐body problem turns out to be the computation of the underlying pair‐distribution functions gee, gei, and gii, that directly yield nonlocal exchange‐correlation potentials, free energies etc., valid within the timescales of each evolving system. An accurate classical map of the strongly‐quantum uniform electron‐gas problem given by Dharma‐wardana and Perrot is reviewed. This replaces the quantum electrons at T = 0 by an equivalent classical fluid at a finite temperature Tq, and having the same correlation energy. The classical map is used with classical molecular dynamics (CMMD) or hyper‐netted‐chain integral equations (CHNC) to determine the pair‐distribution functions (PDFs), and hence their thermodynamic and linear transport properties. The CHNC is very efficient for calculating the PDFs of uniform systems, while CMMD is more adapted to nonuniform systems. Applications to 2D and 3D quantum fluids, Si metal‐oxide‐field‐effect transistors, Al plasmas, shock‐compressed deuterium, two‐temperature plasmas, pseudopotentials, as well as calculations for parabolic quantum dots are reviewed. © 2011 Wiley Periodicals, Inc. Int J Quantum Chem, 2012
On series of signed vectors and their rearrangements
Authors: Banaszczyk Wojciech
Published: June 2011

Let x1,…,xm∈
\input amssym $ \Bbb R$n be a sequence of vectors with ∥xi∥2 ≤ 1 for all i. It is proved that there are signs ε1,…,εm = ±1 such that

where C1, C2 are some numerical constants. It is also proved that there are signs ε,…,ε = ±1 and a permutation π of {1,…,m} such that

where C′ is some other numerical constant. © 2011 Wiley Periodicals, Inc. Random Struct. Alg., 2011
ATR‐FTIR Kretschmann spectroscopy for interfacial studies of a hidden aluminum surface coated with a silane film and epoxy I. Characterization by IRRAS and ATR‐FTIR
Authors: Öhman Maria , Persson Dan
Published: June 2011

Interfacial analysis is essential in many areas of interest, for instance within the ongoing research on environmentally friendly pretreatments of metal surfaces. While studies of the hidden interface between a metal and polymer top‐coat are of great importance, properties of a surface confined between two media are difficult to analyze in detail. Within the two parts of this study, ATR‐FTIR spectroscopy in the Kretschmann geometry is employed as the main analytical tool to study the interface between a thermo‐cured epoxy and aluminum pretreated with a silane film. The technique requires model systems based on thin metal films, but in contrast to most analytical techniques it permits the analysis of a hidden interface. Initial characterization of the silane film formed from a pH‐regulated γ‐APS and BTSE solution was conducted by both ATR‐FTIR Kretschmann and IRRAS spectroscopy. Absorption bands were obtained at 1250–900 cm−1, assigned to SiO functionalities, and at ∼1570 and ∼1410 cm−1 assigned to acetate existing as a counter‐ion to γ‐APS. After application of the epoxy film, interfacial alterations were detected upon thermal curing including the densification of the epoxy film, the dehydration of aluminum and the formation of molecular epoxy reaction products. Few alterations could be assigned to the silane film. Calculated spectra derived from optical data can verify experimental results and aid data interpretation, and effects of metal oxidation of aluminum were confirmed by introducing gold as an additional substrate. The results showed that ATR‐FTIR Kretschmann spectroscopy is clearly a valuable tool for the study of hidden interfaces of stratified media. Copyright © 2011 John Wiley & Sons, Ltd.
Bioactivity and mechanical properties of nickel‐incorporated hydrogenated carbon nanocomposite thin films
Authors: Bharathy P.Vijai , Nataraj D. , Yang Q. , Kiran M.S.R.N.
Published: June 2011

In this paper, the influence of nickel incorporation on the mechanical properties and the in vitro bioactivity of hydrogenated carbon thin films were investigated in detail. Amorphous hydrogenated carbon (a‐C:H) and nickel‐incorporated hydrogenated carbon (Ni/a‐C:H) thin films were deposited onto the Si substrates by using reactive biased target ion beam deposition technique. The films' chemical composition, surface roughness, microstructure and mechanical properties were investigated by using XPS, AFM, TEM, nanoindentation and nanoscratch test, respectively. XPS results have shown that the film surface is mainly composed of nickel, nickel oxide and nickel hydroxide, whereas at the core is nickel carbide (Ni3C) only. The presence of Ni3C has increased the sp2 carbon content and as a result, the mechanical hardness of the film was decreased. However, Ni/a‐C:H films shows very low friction coefficient with higher scratch‐resistance behavior than that of pure a‐C:H film. In addition, in vitro bioactivity study has confirmed that it is possible to grow dense bone‐like apatite layer on Ni/a‐C:H films. Thus, the results have indicated the suitability of the films for bone‐related implant coating applications. Copyright © 2011 John Wiley & Sons, Ltd.
A case study of model‐based Bayesian dose response estimation
Authors: Tan Huaming , Gruben David , French Jonathan , Thomas Neal
Published: June 2011

A Bayesian nonlinear longitudinal Emax model for a binary endpoint was used to characterize the dose–response relationship for a new treatment of rheumatoid arthritis. The model includes prespecified parametric functions for the dependence of response on dose level and time. It was selected based on pharmacometric input about likely dose and time trends. The longitudinal model was useful for combining data collected at different doses and times from two different studies. The example illustrates the utility of more substantive parametric models to guide selection of doses outside the initial dosing range when designing an additional phase 2 study and for extrapolating shorter‐term phase 2 dose response to longer‐term phase 3 studies, as is often required for dosing decisions in drug development for chronic diseases. Comparison of the estimated dose response from the longitudinal model with a corresponding logistic regression model applied at a single time point also demonstrated improved precision. Specification of an informative prior distribution based on numerous sources of prior information is described. This was the most difficult step in the analysis and one that has limited the use of Bayesian methods in similar applications. Model fit was evaluated and the potential impact of some model deficiencies on the dosing decision was assessed. Analyses of the combined studies identified doses likely to achieve a targeted effect in larger and longer confirmatory trials. Copyright © 2011 John Wiley & Sons, Ltd.
The impact of selection bias on test decisions in randomized clinical trials
Authors: Lieven Nils Kennes  , Cramer Erhard , Hilgers Ralf‐Dieter , Heussen Nicole
Published: June 2011

Selection bias affects the evaluation of clinical trials, for example, by elevating type I error rate. We investigated the effect of selection bias on type I error rate considering permuted block randomization. We also considered stratified randomization in general and for the special case of multicenter clinical trials, where we incorporated preferences of the investigator in our approach. Finally, the effect of underrunning is modeled, that is, where the randomization list exceeds the actual number of patients taking part in the trial. For all situations, we illustrate and discuss the impact of selection bias on type I error rate. Copyright © 2011 John Wiley & Sons, Ltd.
Dynamic clustering detection through multi‐valued descriptors of dermoscopic images
Authors: Cozza Valentina , Guarracino Maria Rosario , Maddalena Lucia , Baroni Adone
Published: June 2011

This paper introduces a dynamic clustering methodology based on multi‐valued descriptors of dermoscopic images. The main idea is to support medical diagnosis to decide if pigmented skin lesions belonging to an uncertain set are nearer to malignant melanoma or to benign nevi. Melanoma is the most deadly skin cancer, and early diagnosis is a current challenge for clinicians. Most data analysis algorithms for skin lesions discrimination focus on segmentation and extraction of features of categorical or numerical type. As an alternative approach, this paper introduces two new concepts: first, it considers multi‐valued data that scalar variables not only describe but also intervals or histogram variables; second, it introduces a dynamic clustering method based on Wasserstein distance to compare multi‐valued data. The overall strategy of analysis can be summarized into the following steps: first, a segmentation of dermoscopic images allows to identify a set of multi‐valued descriptors; second, we performed a discriminant analysis on a set of images where there is an a priori classification so that it is possible to detect which features discriminate the benign and malignant lesions; and third, we performed the proposed dynamic clustering method on the uncertain cases, which need to be associated to one of the two previously mentioned groups. Results based on clinical data show that the grading of specific descriptors associated to dermoscopic characteristics provides a novel way to characterize uncertain lesions that can help the dermatologist's diagnosis. Copyright © 2011 John Wiley & Sons, Ltd.
Stress‐Temperature‐Transformation and Deformation‐Temperature‐Transformation Diagrams for an Austenitic CrMnNi as‐cast Steel
Authors: Kovalev A. , Jahn A. , Weiß A. , Wolf S. , Scheller P. R.
Published: June 2011

Stress‐Temperature‐Transformation (STT) and Deformation‐Temperature‐Transformation (DTT) diagrams are well‐suited to characterize the TRIP (transformation‐induced plasticity) and TWIP (twinning‐induced plasticity) effect in steels. The triggering stresses for the deformation‐induced microstructure transformation processes, the characteristic temperatures, the yield stress and the strength of the steel are plotted in the STT diagram as functions of temperature. The elongation values of the austenite, the strain‐induced twins and martensite formations are shown in the DTT diagram.

The microstructure evolution of a novel austenitic Cr‐Mn‐Ni (16%Cr, 6% Mn, 6% Ni) as‐cast steel during deformation was investigated at various temperatures using static tensile tests, optical microscopy and the magnetic scale for the detection of ferromagnetic phase fraction. At the temperatures above 250 °C the steel only deforms by glide deformation of the austenite. Strain‐induced twinning replaces the glide deformation at temperatures below 250 °C with increasing strain. Below 100 °C, the strain‐induced martensite formation becomes more pronounced. The kinetics of the α'‐martensite formation is described according to stress and deformation temperatures. The STT and DTT diagrams, enhanced with the kinetics of the martensite formation, are presented in this paper.
First Principles Calculation of the Thermal Volume Expansion Coefficient of Tetragonal Zircon Dioxide
Authors: Lamowski Simon , Schmerler Steve , Kutzner Jürgen , Kortus Jens
Published: June 2011

We present a general method to calculate thermodynamical properties of crystalline materials from first principles based on density functional theory (DFT). In order to introduce temperature effects we calculate the phonon dispersion for different volumes which allows to include their entropic effects in the Helmholtz free energy. As an example we focus on the calculation of the thermal volume expansion coefficient of tetragonal ZrO2.
Einsatz von warmgefertigten Hohlprofilen mit Wanddicken bis 20 mm bei tiefen Temperaturen
Authors: Stranghöner Natalie , Lorenz Christoph , Krampen Jürgen
Published: July 2011

Warmgefertigte Hohlprofile nach DIN EN 10210 werden derzeit in Europa hauptsächlich in Wanddicken bis 20 mm in der bei den Stahlhändlern in der Regel vorrätigen Güte S355J2H eingesetzt. Eine immer wieder kehrende Frage betrifft die Einsatzfähigkeit dieser Hohlprofile bei tiefen Temperaturen bedingt durch die in der Produktnorm festgelegte Prüftemperatur der Kerbschlagzähigkeit bei —20 °C: Ist ein Stahl der Güte S355J2H auch unterhalb von —20 °C Außentemperatur einsetzbar oder sollte aus Sicherheitsüberlegungen heraus lieber eine höherwertige Stahlgüte eingesetzt werden? Der vorliegende Beitrag beschreibt das Zähigkeitsverhalten von warmgefertigten Hohlprofilen auf der Basis experimenteller Untersuchungen und erläutert den Zusammenhang zwischen der in den Produktnormen geforderten Mindestzähigkeit bei definierter Prüftemperatur und dem bruchmechanisch basierten Sprödbruchkonzept der DIN EN 1993‐1‐10 zur Stahlgütewahl.

The use of hot‐finished hollow sections with wall thicknesses up to 20 mm at low temperatures. In Europe, hot‐finished hollow sections according to DIN EN 10210 are mainly used with wall thicknesses up to 20 mm and steel grade S355J2H which is normally in stock at the steel suppliers. A recurring question concerns the usability of those hollow sections at low temperatures due to the test temperature of impact toughness at —20 °C set in the product standard: Is a steel grade S355J2H applicable below —20 °C service temperature, or should, by security considerations, rather a higher‐quality steel be used? This paper describes the toughness behaviour of hot‐finished hollow sections based on experimental studies and explains the relationship between the required impact toughness in the product standards at a defined test temperature and the fracture mechanics based concept for the choice of steel material of DIN EN 1993‐1‐10.
Korrekturvorschläge für die DIN EN 1993‐1‐8 zum Thema Hohlprofilanschlüsse
Authors: Wardenier Jaap , Puthli Ram
Published: July 2011

Die aktuelle Fassung der DIN EN 1993‐1‐8 enthält ein umfangreiches Kapitel zum Thema Anschlüsse mit Hohlprofilen. Im vorliegenden Beitrag werden hierzu Korrekturvorschläge vorgestellt und sofern erforderlich ihr wissenschaftlicher Hintergrund erläutert. Die Korrekturvorschläge betreffen Fehler und Unklarheiten im Text, sinnentstellende Fehler bei Gleichungen und Anwendungsgrenzen, weiterhin Korrekturen, die wegen der Ausdehnung des Anwendungsbereichs auf Stähle S 460 erforderlich sind und solche, die auf Forschungsergebnissen der letzten 20 Jahre basieren, die Sicherheitslücken aufgezeigt haben. Insbesondere wird der lastmindernde Einfluss großer Zugnormalspannungen im Gurt auf die Knotentragfähigkeit diskutiert.

Proposed corrections to EN 1993‐1‐8, dealing with hollow section joints. The latest version of Eurocode EN 1993‐1‐8 has an exclusive chapter dealing with hollow section joints. This article proposes corrections relating to hollow section joints and explains the relevant research background where necessary. The proposed corrections concern errors in the text, the formulation and the validity range, confusing statements and corrections necessary for the extension of steel grades up to S 460. Also, corrections based upon research results in the last 20 years are given, which have shown that the safety level is lower than expected, such as the influence of chord tensile stress on the joint capacity.
Evaluation of residual welding stresses and fatigue crack behavior in tubular K‐joints in compression
Authors: Acevedo Claire , Nussbaumer Alain , Drezet Jean‐Marie
Published: July 2011

Tubular bridge design has to deal with fatigue issues. The fatigue susceptibility of these bridges, composed of circular hollow section profiles welded together in K‐joints, is mainly due to stress concentrations, to welding imperfections and to tensile residual stresses induced by the welding process.

Since these residual stresses are unknown for K‐joints, measurements were carried out in vicinity of weld toes using the incremental hole‐drilling method, X‐ray diffraction and in particular neutron diffraction. Results from these techniques show that on the first millimeters from the surface, the most important tensile residual stresses are oriented perpendicular to the weld direction and reach the yield strength. Fatigue tests on two large‐scale truss specimens were carried out. They show that tensile residual stresses have a strong influence on crack propagation in K‐joints under applied compressive stresses down to a crack depth of 2 to 3 mm from the surface. Thermo‐mechanical analyses are performed in 3D using two finite element codes: ABAQUS and MORFEO. Computed residual stresses in the region surrounding the weld are compared with measured residual stresses in order to discuss the ability of the simulations to reproduce the residual stress field pattern and estimate the stress values.

Ermittlung von Eigenspannungen und Verhalten von Ermüdungsrissen in geschweißten K‐Hohlprofilverbindungen unter Druck. Bei der Konstruktion von Brücken aus Rundhohlprofilen sind Materialermüdungsprobleme zu beachten. Derartige Brücken sind durch K‐förmige Strebenverbindungen (im Folgenden K‐Verbindungen genannt) verschweißt. Ihre Anfälligkeit für Materialermüdung entsteht vor allem durch Spannungskonzentrationen sowie durch Unregelmäßigkeiten und Eigenspannungen, die beim Schweißen erzeugt werden.

Da die Höhe dieser Eigenspannungen für K‐Verbindungen unbekannt ist, wurden Messungen in der Nähe der Schweißnahtübergänge durchgeführt. Messmethoden waren die inkrementelle Bohrlochmethode, die Röntgendiffraktometrie und insbesondere die Neutronendiffraktometrie. Die Messergebnisse zeigen, dass die wichtigsten Zug‐Eigenspannungen auf den ersten Millimetern unterhalb der Oberfläche rechtwinklig zur Schweißnaht verlaufen und die Streckgrenze erreichen. Ermüdungstests wurden an zwei großen Trägern durchgeführt. Sie zeigen, dass Zug‐Eigenspannungen bei gleichzeitig bestehenden Druckspannungen einen starken Einfluss auf Rissausbreitung in K‐Verbindungen haben; bis zu einer Tiefe von 2 bis 3 mm unterhalb der Oberfläche. Thermomechanische Analysen werden in 3D‐Modellen unter Verwendung zweier Finite‐Elemente‐Programme durchgeführt: ABAQUS und MORFEO. Hierdurch berechnete Eigenspannungen in der Umgebung der Schweißnaht werden mit den gemessenen Werten verglichen, um die Eignung der Simulationen zu prüfen, die Eigenspannungsfelder darzustellen und die Spannungswerte überschlägig zu ermitteln.
Production of L(+) lactic acid from sweet sorghum, date palm, and golden syrup as alternative carbon sources
Authors: Yadav Anil K. , Bipinraj Nirichan K. , Chaudhari Ambalal B. , Kothari Ramanlal M.
Published: June 2011

Lactic acid production has been carried out using (a) Lactobacillus delbruckii, (b) optimal production medium comprised of 10% carbon source derived from sweet sorghum (SS) (Sorghum bicolor)/golden syrup (GS; molasses after glucose crystallization)/date palm (DP) juice (Phoenix dactylifera L.), 1% yeast extract, 0.6% sodium acetate, 0.5% KH2PO4, and 0.5% MgSO4 · 7H2O, (c) in batch mode, (d) at 45 ± 1°C, 150 rpm, anaerobic condition, and pH 5.5 ± 0.1, and (e) sterilized CaCO3 powder at regular intervals for neutralization to promote optimal utilization of sugar. The lactic acid (LA) productivity was higher from the use of GS and less from SS as well as DP juice. Decolorization of carbon sources prior to use in fermentation gave LA, meeting food grade specifications.
Globalization of science education: Comment and a commentary
Authors: Fensham Peter J.
Published: June 2011

The globalized nature of modern society has generated a number of pressures that impact internationally on countries' policies and practices of science education. Among these pressures are key issues of health and environment confronting global science, global economic control through multi‐national capitalism, comparative and competitive international testing of student science achievement, and the desire for more humane and secure international society. These are not all one‐way pressures and there is evidence of both more conformity in the intentions and practices of science education and of a greater appreciation of how cultural differences, and the needs of students as future citizens can be met. Hence while a case for economic and competitive subservience of science education can be made, the evidence for such narrowing is countered by new initiatives that seek to broaden its vision and practices. The research community of science education has certainly widened internationally and this generates many healthy exchanges, although cultural styles of education other than Western ones are still insufficiently recognized. The dominance of English language within these research exchanges is, however, causing as many problems as it solves. Science education, like education as a whole, is a strongly cultural phenomenon, and this provides a healthy and robust buffer to the more negative effects of globalization. © 2011 Wiley Periodicals, Inc., Inc. J Res Sci Teach 48: 698–709, 2011
A novel way of visualizing the ductal and aortic arches by real‐time three‐dimensional ultrasound with live xPlane imaging
Authors: Xiong Y. , Chen M. , Chan L. W. , Ting Y. H. , Fung T. Y. , Leung T. Y. , Lau T. K.
Published: June 2011

Objective

To describe a novel method of visualizing the ductal and aortic arches by real‐time three‐dimensional echocardiography with live xPlane imaging.

Methods

Live xPlane imaging was used to display the ductal‐ and aortic‐arch views in 107 women with singleton pregnancies, including seven cases with suspected congenital heart defects (CHDs). The three vessels and trachea (3VT) view was obtained in such an orientation that either the pulmonary artery or the aorta was parallel to the direction of the ultrasound beam. The xPlane reference line was then placed across the targeted vessel, which in a normal case would provide an image of the corresponding arch view as a dual‐image display.

Results

Once the 3VT view had been obtained, live xPlane imaging showed the aortic and ductal arches in all 100 normal cases. In seven cases with suspected CHD, the 3VT view was abnormal in five cases and normal in the other two. However, the ductal‐arch view demonstrated by live xPlane imaging was abnormal in five cases of conotruncal anomalies and normal in two cases in which conotruncal anomalies were excluded. CHDs were confirmed at autopsy following termination of pregnancy in five cases and on postnatal echocardiography in one case. The heart was found postnatally to be normal in one case of suspected CHD; in this case live xPlane imaging showed that the observed abnormal 3VT view was caused by a tortuous course of the thoracic aorta associated with an abnormal diaphragm.

Conclusion

Live xPlane imaging is a novel and relatively simple method of visualizing the ductal‐ and aortic‐arch views, and may potentially be a useful tool in the screening of fetal conotruncal and aortic‐arch anomalies. Copyright © 2012 ISUOG. Published by John Wiley & Sons, Ltd.
A request control scheme for data recovery in DVB‐IPDC systems with spatial and temporal packet loss
Authors: Yang Wen‐Hsin , Wang You‐Chiun , Tseng Yu‐Chee , Lin Bao‐Shuh Paul
Published: June 2011

Recently, digital video broadcasting‐handheld (DVB‐H) and IP datacast over DVB‐H (DVB‐IPDC) have been developed to support broadcasting services. DVB‐H is designed to support digital video broadcast for handheld devices, whereas DVB‐IPDC can integrate with an IP‐relay network to complement the data loss problem in DVB‐H. Assuming that WiMAX networks are adopted to support DVB‐IPDC, this paper points out two critical problems: group packet loss (GPL) and broadcast data handover (BDH). GPL occurs when there is a burst of retransmission requests for the same pieces of data with high spatial or temporal correlation. BDH happens when some devices that made the above requests handover to new serving cells. To solve these problems, we propose lazy wait and group acknowledgement schemes to alleviate duplicate requests by exploiting their spatial and temporal correlations. This not only reduces the requests submitted by neighboring devices in both space and time domains but also avoids handovering devices from sending duplicate requests in new cells. Through mathematical analysis, we show how to adaptively adjust the timers of lazy wait and group acknowledgement based on channel quality. Simulation results prove that our schemes can efficiently reduce retransmission requests and retransmission packets, thus alleviating congestion in the IP‐relay network. Copyright © 2011 John Wiley & Sons, Ltd.
Energy decomposition analysis
Authors: Hopffgarten Moritz von , Frenking Gernot
Published: June 2011

The energy decomposition analysis (EDA) is a powerful method for a quantitative interpretation of chemical bonds in terms of three major expressions. The instantaneous interaction energy ΔEintbetween two fragments A and B in a molecule A–B is partitioned in three terms, namely, (1) the quasiclassical electrostatic interaction ΔEelstatbetween the fragments, (2) the repulsive exchange (Pauli) interaction ΔEPaulibetween electrons of the two fragments having the same spin, and (3) the orbital (covalent) interaction ΔEorb, which comes from the orbital relaxation and the orbital mixing between the fragments. The latter term can be decomposed into contributions of orbitals with different symmetry, which makes it possible to distinguish betweenσ, π, andδbonding. After a short introduction into the theoretical background of the EDA, we present illustrative examples of main group and transition metal chemistry. The results show that the EDA terms can be interpreted in a chemically meaningful way, thus providing a bridge between quantum chemical calculations and heuristic bonding models of traditional chemistry. © 2011 John Wiley & Sons, Ltd.

This article is categorized under:

Structure and Mechanism > Molecular Structures