bluuebunny/crossref_metadata_2025 huggingface dataset:
Stimulating luteinizing hormone
Authors: Goebel Catrin
Published: December 2011

Low molecular weight luteinizing hormone (LMWLH) receptor agonists could be of interest as a potential doping substance for athletes. These orally active compounds induce the production of endogenous hormones such as testosterone in a similar way to LH. A method for the detection of these compounds needs to be direct as their effect – the excess production of endogenous hormones – cannot be proven by analysis techniques which test for endogenous hormones. In order to detect a broad range of potential LMWLH receptor agonists, a precursor ion monitoring liquid chromatography tandem mass spectrometry method was developed. The method was tested against a selection of urine samples to ascertain potential problems with background analytes interfering with the compounds of interests. Selected compounds were extracted with an established methodology from urine to determine suitability of implementing into general screening methodologies. The two available LMWLH receptor agonists could be detected at concentrations of 100 ng/ml in urine samples. This establishes a basic precursor ion monitoring method suitable for screening purposes for the detection of LMWLH receptor agonists in urine samples. Copyright © 2011 John Wiley & Sons, Ltd.
Chloroplast genome sequence confirms distinctness of Australian and Asian wild rice
Authors: Waters Daniel L. E. , Nock Catherine J. , Ishikawa Ryuji , Rice Nicole , Henry Robert J.
Published: December 2011

Cultivated rice (Oryza sativa) is an AA genome Oryza species that was most likely domesticated from wild populations of O. rufipogon in Asia. O. rufipogon and O. meridionalis are the only AA genome species found within Australia and occur as widespread populations across northern Australia. The chloroplast genome sequence of O. rufipogon from Asia and Australia and O. meridionalis and O. australiensis (an Australian member of the genus very distant from O. sativa) was obtained by massively parallel sequencing and compared with the chloroplast genome sequence of domesticated O. sativa. Oryza australiensis differed in more than 850 sites single nucleotide polymorphism or indel from each of the other samples. The other wild rice species had only around 100 differences relative to cultivated rice. The chloroplast genomes of Australian O. rufipogon and O. meridionalis were closely related with only 32 differences. The Asian O. rufipogon chloroplast genome (with only 68 differences) was closer to O. sativa than the Australian taxa (both with more than 100 differences). The chloroplast sequences emphasize the genetic distinctness of the Australian populations and their potential as a source of novel rice germplasm. The Australian O. rufipogon may be a perennial form of O. meridionalis.
Effects of typhoon Morakot on a large shallow lake ecosystem, Lake Taihu, China
Authors: Ding Yanqing , Qin Boqiang , Zhu Guangwei , Wu Tingfeng , Wang Yongping , Luo Liancong
Published: December 2011

A case study of typhoon‐induced sediment resuspension and its effects on some indicators of water quality (dissolved oxygen, pH and turbidity) and nutrient release in the large shallow eutrophic Lake Taihu, the third largest freshwater lake in China, was documented, and its effect on the algal biomass was investigated. Typhoon Morakot that swept from the west of Lake Taihu in August 2009 led to a number of changes in the lake ecosystem: (1) intensive winds produced large seiches, strong waves and large wave‐induced shear stress; (2) typhoon Morakot led to increased suspended solids and nutrients in the water column. Post‐typhoon concentrations of suspended solid, total phosphorus, total nitrogen, soluble reactive phosphorus (SRP). NO3‐N and NH4‐N were 4, 2, 1·5, 2·5, 3·5 and 1·5 times those observed in the pre‐typhoon water column, respectively; and (3) during typhoon Morakot, there was no obvious stratification between the surface and bottom of the water column in chlorophyll a (Chl a), the post‐typhoon Chl a concentration throughout the water column increased with a maximum daily mean of 87·8 µg l−1, and the algal bloom recurred. Typhoon‐induced sediment resuspension could lead to both nutrient and light limitations for algal growth, whereas after the typhoon had passed, water column conditions (water temperature, solar radiation, light penetration and nutrient availability) favoured the growth and production of algae. Copyright © 2011 John Wiley & Sons, Ltd.
Capillary electrophoresis of natural products: Highlights of the last five years (2006–2010)
Authors: Rabanes Heide R. , Guidote Armando M. , Quirino Joselito P.
Published: December 2011

An extensive search of the published research and review articles indicated a growing number of works that employed electroseparation techniques. Capillary zone electrophoresis (CZE) and electrokinetic chromatography (EKC), in particular, were found to be popular for the analyses of natural products. This review outlines the important developments in this field over the years, especially during the 2006–2010 period. An overview of the natural product applications such as pharmaceuticals/herbal products, fingerprinting and quality control, food and food contaminants, and toxicological compounds of interest to forensics were presented. Important areas of detection strategies, microchips, sample preconcentration, and chiral separations were also discussed. Hence, quick information was provided on the researches already undertaken and the possibilities of unexplored areas. In addition, fundamental concepts for the understanding of CZE and EKC and their suitability for natural products analyses were briefly discussed.
The Wnt secretion protein Evi/Gpr177 promotes glioma tumourigenesis
Authors: Augustin Iris , Goidts Violaine , Bongers Angelika , Kerr Grainne , Vollert Gordon , Radlwimmer Bernhard , Hartmann Christian , Herold‐Mende Christel , Reifenberger Guido , von Deimling Andreas , Boutros Michael
Published: December 2011

Malignant astrocytomas are highly aggressive brain tumours with poor prognosis. While a number of structural genomic changes and dysregulation of signalling pathways in gliomas have been described, the identification of biomarkers and druggable targets remains an important task for novel diagnostic and therapeutic approaches. Here, we show that the Wnt‐specific secretory protein Evi (also known as GPR177/Wntless/Sprinter) is overexpressed in astrocytic gliomas. Evi/Wls is a core Wnt signalling component and a specific regulator of pan‐Wnt protein secretion, affecting both canonical and non‐canonical signalling. We demonstrate that its depletion in glioma and glioma‐derived stem‐like cells led to decreased cell proliferation and apoptosis. Furthermore, Evi/Wls silencing in glioma cells reduced cell migration and the capacity to form tumours in vivo. We further show that Evi/Wls overexpression is sufficient to promote downstream Wnt signalling. Taken together, our study identifies Evi/Wls as an essential regulator of glioma tumourigenesis, identifying a pathway‐specific protein trafficking factor as an oncogene and offering novel therapeutic options to interfere with the aberrant regulation of growth factors at the site of production.
Evidence for an increase in trisomy 21 (Down syndrome) in Europe after the Chernobyl reactor accident
Authors: Sperling Karl , Neitzel Heidemarie , Scherb Hagen
Published: December 2011

The objective of this study is to investigate the prevalence of Down syndrome (DS) associated with Chernobyl fallout. Maternal age‐adjusted DS data and corresponding live birth data from the following seven European countries or regions were analyzed: Bavaria and West Berlin in Germany, Belarus, Hungary, the Lothian Region of Scotland, North West England, and Sweden from 1981 to 1992. To assess the underlying time trends in the DS occurrence, and to investigate whether there have been significant changes in the trend functions after Chernobyl, we applied logistic regression allowing for peaks and jumps from January 1987 onward. The majority of the trisomy 21 cases of the previously reported, highly significant January 1987 clusters in Belarus and West Berlin were conceived when the radioactive clouds with significant amounts of radionuclides with short physical half‐lives, especially 131iodine, passed over these regions. Apart from this, we also observed a significant longer lasting effect in both areas. Moreover, evidence for long‐term changes in the DS prevalence in several other European regions is presented and explained by exposure, especially to 137Cs. In many areas, 137Cs uptake reached its maximum one year after the Chernobyl accident. Thus, the highest increase in trisomy 21 should be observed in 1987/1988, which is indeed the case. Based on the fact that maternal meiosis is an error prone process, the assumption of a causal relationship between low‐dose irradiation and nondisjunction is the most likely explanation for the observed increase in DS after the Chernobyl reactor accident. Genet. Epidemiol. 36 : 48–55, 2012. © 2011 Wiley Periodicals, Inc.
The origin and maturation of lagoonal glauconites: a case study from the Oligocene Maniyara Fort Formation, western Kutch, India
Authors: Banerjee Santanu , Chattoraj Shovan Lal , Saraswati P. K. , Dasgupta Somnath , Sarkar Urbashi , Bumby Adam
Published: December 2011

An integrated study of the sedimentology, micropalaeontology, mineralogy and geochemistry of glauconites in the Oligocene Maniyara Fort Formation (western Kutch, India), has been undertaken. Authigenic glauconites, mostly of evolved type, formed within a back‐barrier lagoonal environment. Foraminifera help constrain the biostratigraphy and along with sedimentological evidence, provide information on the depositional conditions. Glauconite in the Maniyara Fort Formation occurs either as infillings within intra‐particle pores of larger foraminifers, or as an altered form of faecal pellets. X‐ray diffraction studies reveal the less mature nature of glauconite infillings compared to the glauconite pellets. Electron microprobe investigation confirms a relative enrichment of K2O and total Fe2O3 in the latter. Both varieties of glauconite formed by initial authigenic precipitation of K‐poor glauconite and subsequently matured by addition of potassium in the interlayer sites and fixation of total iron in the octahedral sites; calcium, magnesium and aluminum were released from the glauconite structure concomitantly. Alkaline conditions during the entire process of glauconite formation did not allow dissolution of foraminiferal tests. Mineralogical and chemical characteristics of the Maniyara Fort Formation glauconites are more similar to deep marine glauconites than those reported from other shallow or marginal marine settings. A low negative cerium anomaly, as well as abundant pyrite, suggests formation of glauconite in sub‐oxic micro‐environments, created by decay of organic matter associated with foraminiferal chambers and faecal pellets. Sub‐oxic condition apparently prevailed relatively longer within the Maniyara Fort Formation lagoons. Copyright © 2011 John Wiley & Sons, Ltd.
Isolation, characterization, and genetic profiling of subpopulations of olfactory ensheathing cells from the olfactory bulb
Authors: Honoré Axel , Le corre Stéphanie , Derambure Céline , Normand Romain , Duclos Célia , Boyer Olivier , Marie Jean‐Paul , Guérout Nicolas
Published: December 2011

Olfactory ensheathing cells (OECs) play a crucial role during neurogenesis of primary olfactory neurons. Transplantation of OECs is considered as a promising new therapy for central nervous system repair. Nevertheless, OECs are constituted of distinct subpopulations and their role during neurogenesis is not clearly understood. In particular, OECs from the olfactory bulb (OB) constitute a heterogeneous, but not yet isolated and characterized, population of cells. In our study, flow cytometry analyses of primary OB cultures, based on cell surface expression of low‐affinity nerve growth factor receptor (p75), reveal the presence of two distinct populations of OECs. Indeed, some of them express a high level of p75 (P75High) and the other a low level of p75 (P75Low). Effects of OB microenvironment were assessed, and we were able to show that fibroblasts mediate the induction of these two populations through the secretion of soluble factors. To characterize P75High and P75Low OECs, cells were sorted based on their differential expression of p75. Microarray analyses revealed that P75High OECs overexpress genes implicated in modulation of extracellular matrix and cell sorting, whereas P75Low OECs overexpress genes involved in regulation of the inflammatory response and axonal guidance. These results permit, for the first time, to isolate the two distinct subpopulations of OECs from OB, and suggest their specific role during neurogenesis. © 2011 Wiley Periodicals, Inc.
Impact messages of depressed outpatients as perceived by their significant others: profiles, therapeutic change, and relationship to outcome
Authors: Grosse Holtforth Martin , Altenstein David , Ansell Emily , Schneider Claudia , Caspar Franz
Published: December 2011

Whereas previous interpersonal research in depression has frequently used self‐reports, patients' impact on others is rarely analyzed. We analyzed impacts of 180 depressed psychotherapy outpatients out of 832 diagnostically heterogeneous patients as rated by their significant others. Depressed patients were perceived as more submissive, hostile‐submissive, and friendly‐submissive, and as less dominant and friendly‐dominant than patients with other principle disorders. After therapy, the 59 depressed patients whose significant others also provided data after treatment were perceived as less submissive (friendly‐submissive, submissive, hostile‐submissive) and more dominant and friendly‐dominant. Whereas a decrease in submissiveness and hostile‐submissiveness was associated with positive outcomes, decrease in friendly‐submissiveness was unrelated. Cluster analyses suggested four distinct interpersonal subgroups. We discuss these results in terms of interpersonal theory and interpersonal assessment in depression therapy.
Association of MR relaxation and cartilage deformation in knee osteoarthritis
Authors: Subburaj K. , Souza R. B. , Stehling C. , Wyman B. T. , Le Graverand‐Gastineau M.‐P. , Link T. M. , Li X. , Majumdar S.
Published: December 2011

We assessed the relationship between cartilage MR relaxation times and biomechanical response of tibiofemoral articular cartilage to physiological loading in healthy subjects and patients with osteoarthritis (OA). Female subjects above 40 years of age with (N1 = 20) and without (N2 = 10) OA were imaged on a 3T MR scanner using a custom made loading device. MR images were acquired with the knee flexed at 20° with and without a compressive load of 50% of the subject's bodyweight. The subjects were categorized based on the clinical MRI scoring of medial and lateral cartilage surfaces. Data were stratified twice into two equal groups (low and high) at the median value of T1ρ and T2 relaxation time. The change in contact area and cartilage deformation was measured within these groups. Paired Student's t‐test (α = 0.05) was used to analyze the effect of loading on contact area and deformation. The average area of the contact region in the medial compartment was significantly higher in OA subjects compared with normal subjects in both unloaded (314 ± 112 mm2 vs. 227 ± 106 mm2, p = 0.023) and loaded (425 ± 128 mm2 vs. 316 ± 107 mm2, p = 0.01) conditions. The overall relative change of cartilage thickness in the medial compartment was significantly higher than the lateral compartment (−5.3 ± 9.9% vs. −1.9 ± 9.2%, p = 0.042). When cartilage was divided into deep and superficial layers, superficial layers showed higher changes in relaxation time (T1ρ and T2) than the changes in relaxation time of whole cartilage (Normal: 12.5% vs. 6.9%; OA: 10.9% vs. 4.6%). The average T1ρ and T2 times, change in area of contact region, and change in cartilage thickness in subjects with OA were higher when compared to normal subjects. This study provides support for a relationship between the mechanical response of cartilage to physiological loading (cartilage‐on‐cartilage contact area and cartilage deformation) and MR relaxation times (T1ρ and T2) in both OA patients and normal subjects. © 2011 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 30:919–926, 2012
An assessment study of tiles from Topkapı Palace Museum with energy‐dispersive X‐ray and Raman spectrometers
Authors: Simsek Gulsu , Geckinli A. Emel
Published: December 2011

A limited number of studies concerning Ottoman ceramic technology have been performed using the scanning electron microscopy‐energy dispersive X‐ray spectrometry and micro‐Raman spectroscopy techniques. The discovery of the ceramics, which were described as ‘Iznik’, at excavation sites outside of the city of Iznik, caused disagreements over the exact origin of Iznik products. In this study, bodies, glazes, and pigments of 46 tile/ceramic shards of unknown origin, which were supplied from the vaults of Topkapı Palace Museum, and two reference tile fragments, known as Kütahya products, supplied from the demolished Surp Krikor Lusavoriç church and, additionally, two Iznik reference tiles were examined using the scanning electron microscopy‐energy dispersive X‐ray spectrometry and micro‐Raman spectroscopy techniques. Results of both techniques were evaluated together for the first time to determine the power of nondestructive Raman spectroscopy technique in differentiation of Ottoman tiles. In this work, bodies of the Kütahya tiles were found to be different than Iznik and Tekfur stone‐paste bodies, which are rich in clay rather than quartz. Two different lead‐alkali glaze compositions were found for Kütahya tiles; one was rich in PbO (over 35%) and the other one was rich in alkali (PbO less than 25%). Barite inclusions were detected in the bodies and in the glazes of some Ottoman tiles, which could be the fingerprint for the Kütahya products. It was found that the under glaze red decoration is essentially a mixture of hematite and quartz in different proportions. Shades of red decoration mainly depend on the amount of hematite in the mixture. Sixteenth century tomato red decoration contains more quartz compared with 17th century dark red decoration. This study showed that a similar technology was also applied at Kütahya in the 16th century. A linear correlation was found between the position of the Raman intense stretching peak Q3 and lead oxide content of lead‐alkali glazes, which could allow for the differentiation of Ottoman tiles based on the nondestructive Raman analysis. This study provides an important additional reference data and discussion for the Ottoman tiles. Copyright © 2011 John Wiley & Sons, Ltd.
Intravenous electrocardiography helps inexperienced operators to place totally implantable venous access device more accurately
Authors: Wang Yi‐Chia , Huang Chi‐Hsiang , Lin Feng‐Sheng , Lin Wen‐Ying , Fan Shou‐Zen , Lin Chih‐Peng , Sun Wei‐Zen
Published: December 2011

Background

Proper tip position is a major determinant of totally implantable venous access device (TIVAD) outcome. The aim of this study is to analyze the potential utilization of intravenous electrocardiography (IV‐ECG) to help inexperienced operators for TIVAD placement.

Patients and Methods

This is a retrospective, observational, uni‐institutional study. 331 patients receiving TIVAD implantation from July 2008 to December 2008 were recruited. In IV‐ECG group, IV‐ECG was used to help decide catheter tip location and catheter length. In Landmark group, catheter length was decided by surface landmarks. Catheter tip position was confirmed by post‐operative supine chest X‐ray.

Results

There were 153 patients in IV‐ECG group, and 178 patients in Landmark group. No immediate reoperation due to catheter mal‐position was noted in IV‐ECG group, but it happened in eight patients in Landmark group. In IV‐ECG group, 97.3% of the catheter tip located at proper position (within 2 cm from junction of right atrium and superior vena cava, as compared to 88.8% of the tip position in Landmark group was proper. The difference was statistically significant (P < 0.05). There was no complication associated with the use of IV‐ECG.

Conclusion

IV‐ECG is a safe and convenient method to help inexperienced operators placing TIVAD. J. Surg. Oncol. 2012; 105:848–851. © 2011 Wiley Periodicals, Inc.
Spatial ecology of white‐tailed deer fawns in the northern Great Plains: Implications of loss of conservation reserve program grasslands
Authors: Grovenburg Troy W. , Klaver Robert W. , Jenks Jonathan A.
Published: December 2011

Few studies have evaluated how wildlife, and white‐tailed deer (Odocoileus virginianus) in particular, respond to Conservation Reserve Program (CRP) grasslands. We conducted a 3‐year study (2007–2009) to determine the influence of CRP on fawn ecology during a time of declining CRP enrollment. We captured and radiocollared 81 fawn white‐tailed deer during 15 May to 15 June 2007–2009 in north‐central South Dakota, collected 6,505 locations, and documented 70 summer home ranges. Mean summer home ranges increased temporally during 2007–2009 (P < 0.001) and corresponded to a 41% loss of CRP grasslands in the area (2.3% loss in land cover and approx. 21% loss in cover habitat in the study area) over the duration of the study. Additionally, mean movement between daily locations increased (P < 0.001) from 2007 to 2009. Analysis of covariance models indicated that change in CRP influenced home‐range size, and change in CRP and wheat influenced daily movement. Smaller home ranges and reduced movements were associated with greater quantity of CRP available to fawns, and increased movements were associated with more acreage of wheat available to fawns. Fawns shifted resource selection during the summer at a mean age ranging from 48.8 days to 58.6 days, and this shift was associated with height of corn (83–87 cm). During early summer, fawns consistently selected for CRP; selection of wheat progressed temporally from avoidance in 2007 to selection in 2009. During late summer, fawns consistently selected for corn habitat and used CRP at least in proportion to its availability. Reduction in CRP‐grasslands seemed to increase fawn home‐range size and daily movements and, influenced change in resource selection to wheat. Current legislation mandates continued decrease in CRP enrollment and concomitant increase in the planting of corn for ethanol production. Management of habitat throughout the grasslands of the Northern Great Plains that maximizes cover habitats would provide neonates with adequate cover for protection from predators. © 2011 The Wildlife Society.
Reproductive output and ultrasonography of an endangered population of East Pacific green turtles
Authors: Blanco Gabriela S. , Morreale Stephen J. , Vélez Elizabeth , Piedra Rotney , Montes Wilder M. , Paladino Frank V. , Spotila James R.
Published: December 2011

Reproductive output is one of the most relevant aspects of life history. We analyzed the reproductive output of the endangered East Pacific green turtle (Chelonia mydas) nesting in Nombre de Jesús, Costa Rica. We supplemented beach patrols with ultrasonography to estimate clutch frequency. With ultrasound scans, we classified the stage of turtle ovaries as: early stage (2 or more clutches), late stage (1 clutch), and depleted ovaries (no clutches). We calculated mean (±SD) estimated clutch frequency (ECF) to be 3.7 ± 1.8 (n = 24) and an adjusted frequency considering individual stage (ECFU; ECF + number of clutches remaining as observed in the last ultrasound) as 5.1 ± 1.3. This is greater than previously described for East Pacific green turtles. Greater individual output could be representative of a healthier population; but could also indicate a decrease in the estimate population numbers previously reported. © 2011 The Wildlife Society.
TouchPoints: The power of leading in the moment
Authors: Conant Doug , Norgaard Mette
Published: December 2011

A leader's day is continuously punctuated by interruptions and interactions of all types. Rather than treating these events as nuisances, Conant and Norgaard advise to think of them as TouchPoints, opportunities to provide leadership and “to generate energy and direction around something that matters.” If you shift your perspective to thinking or saying, “How can I help?,” you have the potential to make a positive impact on your organization in a short moment of time. Your reputation, Conant and Norgaard contend, is shaped in these moments day after day.
Not Any New Functional Polymer Can Be for Medicine: What About Artificial Biopolymers?
Authors: Vert Michel
Published: December 2011

Man‐made artificial organic polymers are among the more recent sources of materials used by humans. In medicine, they contribute to applications in surgery, dentistry and pharmacology. Nowadays, innovations in the field of therapeutic polymers rely on novel polymers for specific applications such as guided tissue regeneration, tissue engineering, drug delivery systems, gene transfection, etc. Introducing reactive chemical functions within or along polymer backbones is an attractive route to generate functional polymers for medicine. However, any candidate to effective application must fulfil a number of requirements, grouped under the terms biocompatibility and biofunctionality, to be of real interest and have a future for effective application. Whenever the application requires a therapeutic aid for a limited period of time to help natural healing, bioresorbability is to be taken into account on top of biocompatibility and biofunctionality. This contribution presents the case of “artificial biopolymers” and discusses the potential of some members of the family with respect to temporary therapeutic applications that require functional polymers.

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The corrosion inhibitory property of N,N‐bis(2‐benzimidazolylmethyl)amine for Q235 steel
Authors: Qian J. H. , Zhang Y. , Yin X. Y. , Liu L.
Published: December 2011

The main purpose of this paper is to systematically evaluate the anti‐corrosion property of N,N‐bis(2‐benzimidazolylmethyl)amine (IDB), which is a novel good thermal stabilized inhibitor in acidic medium. Results obtained from electrochemical tests and corrosion surface morphology analyses reveal that IDB performs excellently as corrosion inhibitor for Q235 steel in 1 mol/L hydrochloric acid corrosive solution. Potentiodynamic polarization measurements show that IDB inhibits both the anodic and cathodic processes of corrosion and exhibits as a mixed‐type inhibitor. Besides, the inhibiting efficiency (IE%) and consequently the degree of surface coverage (θ) increase with the inhibitor concentration rising. And when the concentration is 20 × 10−5 mol/L, the corrosion inhibition effect is best to reach 96.39%. The adsorption of inhibitor on Q235 steel is found to obey the Langmuir adsorption isotherm, and the calculated Gibbs free energy demonstrates that IDB spontaneously adsorbs and forms a protective chemisorbed film on Q235 steel to restrain its corrosion. Hereby, IDB will become a promising corrosion inhibitor in further.
Electrochemical investigations on the corrosion behaviour of galvanized reinforcing steels in concrete with chromate‐reduced cements
Authors: Ebell G. , Burkert A. , Lehmann J. , Mietz J.
Published: December 2011

The reduction of the chromate contents in cements affects the electrochemical reactions of galvanized reinforcing steels in fresh concrete. By means of electrochemical measurements and bar pull‐out tests the effect of chromates on the formation of protective coatings at the zinc and the bond behaviour have been investigated using chromate‐containing and chromate‐reduced cements. The results have shown that the bond zone was affected as a result of chromate reduction for cement types CEM I and CEM II. The disturbance to the bond zone should be considered as long‐term in relation to the pore structure which is formed. The effects on the bond are largely compensated for as the concrete ages. The results of the related bond strength with displacement paths of 0.1 and 0.5 mm, respectively, are still within the range of expected figures for non‐galvanized reinforcing steel despite the structural disturbance. Under practical aspects it is not necessary that the existing structural disturbance with respect to bond strength is taken into consideration.
Effect of exposure time on the morphology of corrosion on high chromium white cast iron in high temperature caustic solutions
Authors: McLeod A. J. , Clegg R. E.
Published: December 2011

High chromium white irons are important candidate materials for use in alumina refineries to combat wear and corrosion. The effect of exposure time on the formation of oxide films was studied in a 23% Cr white cast iron exposed at 260 °C in 110 g/l caustic soda solutions. It was found that whilst well‐formed octahedral M(II)O.M(III)2O3 spinel type oxides initially formed and spread across the surface of the material, these were gradually replaced by a background oxide with a higher Cr/Fe ratio and the morphology of the octahedral crystals became less well formed. Also, the oxidation was found to be predominantly in the matrix material, leaving carbide particles unsupported on the surface and in the later stages, significant corrosion was found along the carbide/matrix phase boundary.
Effect of aluminum on the corrosion resistance of low‐alloy steel in 10 wt% sulfuric acid solution
Authors: Nam N. D. , Kim W. C. , Kim J. G.
Published: December 2011

The aqueous corrosion behavior of low‐alloy steel with aluminum contents was examined in a 10 wt% H2SO4(pH 0.13) solution using electrochemical techniques and surface analyses. The corrosion resistance of the new alloy steel was evaluated in terms of electrochemical parameters, such as passive current density, film, and charge transfer resistances. The results showed that a high Al content in the steel imparted better passivation behavior resulting in a lower corrosion rate. It related to the enrichment of iron carbonate and hydrocarbon by the dissolution of the carbide phase.
Spatial distribution and formation of corrosion products in relation to zinc release for zinc sheet and coated pre‐weathered zinc at an urban and a marine atmospheric condition
Authors: Hedberg J. , Le Bozec N. , Wallinder I. Odnevall
Published: December 2011

Zinc release data from 5 years of unsheltered exposures in a marine and an urban site is compiled for different zinc material types. The thin surface treatment on zinc materials is gradually detached after approximately 2 years at both sites, revealing the pre‐weathered zinc surface unprotected. This consequently increased the release rates of zinc from this surface, whereas the zinc runoff rate from the bare zinc sheet remained relatively stable. Raman studies on bare zinc sheet exposed for 5 years at the marine site revealed zinc oxide of varying crystalline nature and hydrozincite to appear localized and separated from each other.
Polystyrene‐Based C60 Acceptor Copolymers through Azide–Alkyne Click Chemistry Approaches
Authors: Heuken Maria , Komber Hartmut , Voit Brigitte
Published: December 2011

Poly(styrene‐r‐propargyloxy styrene) with varying molecular weights is prepared by means of a nitroxide‐mediated radical polymerization and a malonate is “clicked” to it. Fullerene C60 is reacted under Bingel conditions with the polymer and can be covalently bound to its side chains. These polymers show good solubility in common organic solvents and intense studies are performed to determine the degree of substitution with fullerenes. A loading of around 15 to 20 wt% is detected by thermogravimetric analyses (TGA). These materials might be promising as the acceptor component for donor–acceptor block copolymers. Furthermore, new bromine‐ and organo‐azide‐functionalized methano fullerenes are prepared and characterized.
Developmental status and home environment among children born to immigrant women married to Taiwanese men
Authors: Chen Chwen‐Jen , Hsu Chiung‐Wen , Chu Yu‐Roo , Han Kuo‐Chiang , Chien Li‐Yin
Published: December 2011

The aims of this cross‐sectional study were to examine (a) the developmental status and home environments of children (6–24 months) of immigrant women married to Taiwanese men, and (b) the association of child developmental status with parental socio‐demographics, maternal language abilities, and home environment qualities. Participants were 61 children and their mothers from China and Vietnam. Data were collected with interviews, home observations, and developmental testing. The children had lower cognitive and language but higher motor and social development scores compared with native norms. Home environment and maternal perceived language ability were positively associated with child development. The association of home environment and maternal language ability with early childhood development was supported for immigrant populations in Taiwan. © 2011 Wiley Periodicals, Inc. Res Nurs Health 35:121–131, 2012
Influence of the processing solvent on the photoactive layer nanomorphology of P3HT/PC60BM solar cells
Authors: Mens Raoul , Demir Fatma , Van Assche Guy , Van Mele Bruno , Vanderzande Dirk , Adriaensens Peter
Published: December 2011

In this article, it is demonstrated that doctor blading of thin poly‐3‐hexylthiophene/phenyl‐C61‐butyric acid methyl ester (1/1) bulk‐hetero junction films from toluene leads to an improved nanocrystallinity, when compared with their unannealed chlorobenzene processed counterparts. This difference in morphology was demonstrated by solid‐state NMR and Rapid Heating Cooling Calorimetry (RHC), being useful complementary techniques to investigate the active layer morphology of photovoltaic devices. An increased PC60BM nanocrystallinity is indicated by several NMR relaxation decay times (T1C, T1H, and T1ρH) and confirmed by an increase of the melting enthalpy in RHC experiments. An improved solar cell performance further strengthens this conclusion. © 2011 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem, 2012
Correlation of Structure and Sensitivity in Inorganic Azides II. Effect of Lattice Defects on Non Bonded Nitrogen to Nitrogen Distances
Authors: Cartwright Michael , Wilkinson Joshua
Published: December 2011

The sensitivity of explosives during handling operation is an important subject for explosives safety. Current ability to predict sensitivity is based on a series of empirical rules for different classes of explosive compounds based on their chemical composition. Whilst these may be valid for organic classes, inorganic materials do not conform to any of these patterns. There was a very good correlation found between impact sensitivity and the minimum non bonded nitrogen to nitrogen distance across a wide variety of azides. This correlation suggests reduction in the atomic movements required to produce the reaction products. This study examines the structure of a number of inorganic azides containing defects using molecular mechanics based on a Universal Force Field (UFF) approach, previously validated for a range of perfect lattices, with RMS deviations of between 7 and 11 pm from the original crystal structure following operation of the minimisation technique from a disordered arrangement.

Using the UFF method, appropriate point defects (Schottky and Frenkel pairs) were modelled for these azides under conditions of maximum and minimum achievable pair separation. The maximum limit on pair separation was a result of the explicit modelling being limited to a 3×3×3 unit cell matrix. The results showed that the minimum non bond nitrogen to nitrogen distance narrowed in the presence of defects for all azides. In two cases, RbN3 and TlN3, this reduction in non bonded nitrogen to nitrogen distances was dramatically different from the other azides and was very dependant on the defect configuration and separation. This may indicate that the sensitivity of these two azides containing defects, is greater than the ideal crystal structure would suggest. If the normal production of this azide produces a significantly defective structure then it may well explain the enhanced sensitivity.
Fast conventional Fmoc solid‐phase peptide synthesis: a comparative study of different activators
Authors: Chantell Christina Ann , Onaiyekan Michael Abayomi , Menakuru Mahendra
Published: December 2011

The ability to speed up conventional Fmoc solid‐phase peptide synthesis (SPPS) has many advantages including increased productivity. One way to speed up conventional Fmoc SPPS is the choice of activator. Recently, several new activators have been introduced into the market, and they were evaluated along with some older activators for their ability to synthesize a range of peptides with shorter and longer reaction times. It was found that HDMC, PyClock, COMU, HCTU, and HATU worked well at shorter reaction times (2 × 1 min), but PyOxim and TFFH only worked well at longer reaction times. The performance of PyBOP at shorter reaction times was poor only for more difficult sequences. These results are important for selecting an appropriate activator for fast SPPS applications. Copyright © 2011 European Peptide Society and John Wiley & Sons, Ltd.
The good taste of peptides
Authors: Temussi Piero A.
Published: December 2011

The taste of peptides is seldom one of the most relevant issues when one considers the many important biological functions of this class of molecules. However, peptides generally do have a taste, covering essentially the entire range of established taste modalities: sweet, bitter, umami, sour and salty. The last two modalities cannot be attributed to peptides as such because they are due to the presence of charged terminals and/or charged side chains, thus reflecting only the zwitterionic nature of these compounds and/or the nature of some side chains but not the electronic and/or conformational features of a specific peptide. The other three tastes, that is, sweet, umami and bitter, are represented by different families of peptides. This review describes the main peptides with a sweet, umami or bitter taste and their relationship with food acceptance or rejection. Particular emphasis will be given to the sweet taste modality, owing to the practical and scientific relevance of aspartame, the well‐known sweetener, and to the theoretical importance of sweet proteins, the most potent peptide sweet molecules. Copyright © 2011 European Peptide Society and John Wiley & Sons, Ltd.
Injection efficiency and optical gain characteristics of polar and nonpolar III‐nitride light emitters
Authors: Kisin Mikhail V. , El‐Ghoroury Hussein S.
Published: December 2011

Optical properties of III‐nitride quantum well (QW) structures grown on nonpolar or semipolar crystallographic planes benefit from reduced internal fields in QWs and, as a result, from enhanced overlap between electron and hole states participating in lasing transition. Detailed modelling of active QWs shows, however, that smaller separation of the lasing states from the high‐energy subbands in nonpolar QWs and related thermal carrier redistribution between subbands can reduce the QW differential optical gain thus increasing the laser threshold. Efficiency characteristics of multiple QW emitters are additionally affected by inhomogeneous QW injection and by large residual QW charges. Polar and nonpolar light‐emitting diode structures reveal different mechanisms of the efficiency droop. In polar structures, the droop is dominated by electron leakage and is noticeably affected by the active region ballistic overshoot. Efficiency droop in nonpolar structures is dominated by combined effect of radiative time saturation and nonradiative Auger recombination while the carrier leakage becomes a factor of secondary importance. (© 2012 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Epitaxial growth and properties of GdN, EuN and SmN thin films
Authors: Natali Franck , Ludbrook Bart , Galipaud Jules , Plank Natalie , Granville Simon , Preston Andrew , Do Bin Le , Richter Jan , Farrell Ian , Reeves Roger , Durbin Steve , Trodahl Joe , Ruck Ben
Published: December 2011

This paper contains a summary of selected aspects of the epitaxial growth of rare‐earth nitride thin films and the recent progress achieved in this field. The discussion is focussed on GdN, SmN, EuN compounds grown by both pulsed laser deposition and molecular beam epitaxy on different substrates including YSZ (001), c‐plane (0001) AlN and GaN. While a N2 plasma cell is used as a nitrogen source for growing EuN, we take advantage of the catalytic breakdown of molecular nitrogen by rare‐earth atoms to grow GdN and SmN in the absence of activated N2. The structural, magnetic and transport properties of the thin films are assessed by reflection high‐energy electron diffraction, x‐ray diffraction, Hall Effect, temperature‐dependent magnetization and resistivity. (© 2012 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Behavior of misfit dislocations in semipolar InGaN/GaN grown by MOVPE
Authors: Kuwahara Takaaki , Kuwano Noriyuki , Kurisu Akihiko , Okada Narihito , Tadatomo Kazuyuki
Published: December 2011

A microstructure in an InGaN/GaN layer grown at the semipolar direction was observed in detail by means of transmission electron microscopy (TEM) in order to analyze the behaviour of dislocations. A (11$ \bar 2 $2) GaN layer was first deposited on a maskless r (1$ \bar 1 $02)‐plane patterned‐substrate, and then an Inx Ga1‐xN (x =0.10, 0.24) was overgrown to be about 1 μm in thickness. Dislocations near the interface of InGaN/GaN are classified into several types: 1 Threading dislocations lying on (0001).

2. Misfit dislocations lying on the interface of InGaN/GaN. 3. Dislocations along [1$ \bar 1 $00] at a certain distance from the interface. 4. Dislocations newly formed at the interface and developing along [11$ \bar 2 $0] on (0001). 5. Partial dislocations accompanied with a stacking fault on (0001).

It was found that the misfit dislocations are arrayed in pairs at the direction along [1$ \bar 1 $00] on the interface of (11$ \bar 2 $2). Burgers vector of the misfit dislocations was found to be B = <2$ \bar 1 $$ \bar 1 $3>/3. In case of B = [$ \bar 1 $$ \bar 1 $23]/3, they are edge dislocations. The densities of dislocations and stacking faults increase with the In‐content in InGaN. (© 2012 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Study of CF4 plasma treatment in drift region optimization of high‐voltage GaN MOSC‐HEMTs
Authors: Li Zhongda , Zhang Jie , Chow T. Paul
Published: December 2011

In this paper we report on our experimental optimization of the CF4 plasma treatment conditions to control the 2DEG density in the drift region of the GaN MOS Channel HEMTs (MOSC‐HEMTs). The 2DEG density was measured using a simple MOS capacitor structure fabricated on the AlGaN/GaN epi treated by CF4 plasma under different conditions. The optimized CF4 plasma power was found to be 350 W for reducing 2DEG density from 1×1013cm‐2 to 2.5×1012cm‐2. Breakdown voltage was projected by numerical simulations to be higher than 800 V with the optimized 2DEG density of 2.5×1012cm‐2. (© 2012 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
The role of liquid phase epitaxy during growth of AlGaN by MBE
Authors: Moustakas Theodore D. , Bhattacharyya Anirban
Published: December 2011

We propose that the growth of III‐Nitride semiconductors by plasma‐assisted MBE under Ga‐rich conditions takes place though the saturation of the liquid Ga covering the surface of the growing film with nitrogen, alloy constituents (aluminum and indium) and impurities. Thus, the proposed growth mode is a liquid phase epitaxy (LPE) rather than physical vapor phase epitaxy. While in traditional LPE growth the driving force is the gradient between the liquid and seed, in the proposed mode of MBE growth of nitrides the driving force is the concentration gradient due to the constant supply of active nitrogen, alloy components and impurities. The proposed LPE growth mechanism explains the relative temperature stability of GaN growth, the efficient doping with silicon and magnesium, and the selective desorption of oxygen and other impurities. Finally, the proposed LPE growth model can also account for the introduction of band structure potential fluctuations in AlGaN alloys, which improves their emission properties and leads to efficient deep UV‐LEDs. (© 2012 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Fabrication of site‐controlled InGaN quantum dots using reactive‐ion etching
Authors: Lee Leung Kway , Ku P.‐C.
Published: December 2011

We adopted the simple top‐down etching to fabricate site‐ and dimension‐controlled InGaN quantum dots. Each quantum dot is disk shaped and embedded in a nanoscale pillar. Arrays of nanopillars with varying densities and nanopillar diameters were fabricated from an InGaN/GaN single quantum well using inductively‐coupled plasma reactive‐ion etching. Micro‐photoluminescence (µ‐PL) was used to characterize the emission properties of individual and ensemble of nanopillars. Strong and distinct PL signal of a single nanopillar was observed even at the room temperature. The emission was found to exhibit characteristics from a discrete energy state that is homogeneously broadened. The ensemble of nanopillars exhibited a similar emission linewidth as the single nanopillar, indicating a well controlled quantum dot dimensions and uniformity. (© 2012 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
N‐polar n+ GaN cap development for low ohmic contact resistance to inverted HEMTs
Authors: Meyer D. J. , Katzer D. S. , Bass R. , Garces N. Y. , Ancona M. G. , Deen D. A. , Storm D. F. , Binari S. C.
Published: December 2011

This study investigates the development and application of Si‐doped N‐polar n+ GaN capping layers used for the reduction of ohmic contact and access resistances in inverted HEMTs. By applying an optimized n+ GaN capping layer to a standard undoped inverted HEMT, we find that non‐alloyed Ti/Al/Ni/Au contacts demonstrate a very low ohmic contact resistance of 80 Ω‐µm. To eliminate the n+ GaN shunting pathway in HEMT devices, we have used e‐beam lithography and dry etching to define windows that establish an effective source‐drain spacing. 0.3 µm gate‐length inverted HEMTs with n+ GaN caps and 1 µm effective source‐drain spacing were found to have a high maximum current density of 1.94 A/mm and an extrinsic transconductance of 335 mS/mm. (© 2012 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Novel metrics for evaluating improvement in discrimination: net reclassification and integrated discrimination improvement for normal variables and nested models
Authors: Pencina Michael J. , D'Agostino Ralph B. , Demler Olga V.
Published: December 2011

Net reclassification and integrated discrimination improvements have been proposed as alternatives to the increase in the area under the curve for evaluating improvement in the performance of risk assessment algorithms introduced by the addition of new phenotypic or genetic markers. In this paper, we demonstrate that in the setting of linear discriminant analysis, under the assumptions of multivariate normality, all three measures can be presented as functions of the squared Mahalanobis distance. This relationship affords an interpretation of the magnitude of these measures in the familiar language of effect size for uncorrelated variables. Furthermore, it allows us to conclude that net reclassification improvement can be viewed as a universal measure of effect size. Our theoretical developments are illustrated with an example based on the Framingham Heart Study risk assessment model for high‐risk men in primary prevention of cardiovascular disease. Copyright © 2011 John Wiley & Sons, Ltd.