bluuebunny/crossref_metadata_2025 huggingface dataset:
Analysis and structure of four lentic communities on the Colorado (U.S.A.) shortgrass prairie
Authors: Herrmann Scott J.
Published: January 2012

Four natural lentic habitats on the Central Plains Experimental Range in Colorado were intensively studied physically, chemically, and biologically for 2 yr (1968–1970) and intermittently for 5 (1971–1975). Lynn Lake and Lake George were chosen as examples of ephemeral or temporary sites, while Cottonwood Pond and Spring Pond were chosen as permanent habitats. Chemically, the waters of each site were analytically separated into dissolved and suspended (sestonic) components. The temporary sites were characterized by their exceptionally high seston loads, the presence of Eubranchiopoda, the prevalence of Ca as the major dissolved cation, ana the high Fe content of their sediments. The two permanent sites, on the other hand, had high total dissolved salt content, rich and varied flora and fauna, Na as the prevalent cation in the dissolved fraction, and high Ca content in the sediments. All four of the sites were “seston digesters” with large amounts of wind‐blown organic material being entrapped, decomposed, and mineralized. By comparison with adjacent soils the sediments of all four basins were much richer in K, Zn, Fe, Cu, and Mn. Both temporary and permanent sites function as nutrient sinks. Rates of daily and annual phytoplankton primary productivity are reported for the two permanent sites.
Spinal modulation of nociception by music
Authors: Roy M. , Lebuis A. , Hugueville L. , Peretz I. , Rainville P.
Published: January 2012

Numerous studies have demonstrated the capacity of music to modulate pain. However, the neurophysiological mechanisms responsible for this phenomenon remain unknown. In order to assess the involvement of descending modulatory mechanisms in the modulation of pain by music, we evaluated the effects of musical excerpts conveying different emotions (pleasant‐stimulating, pleasant‐relaxing, unpleasant‐stimulating) on the spinally mediated nociceptive flexion reflex (orRIII), as well as on pain ratings and skin conductance responses. TheRIIIreflex and pain ratings were increased during the listening of unpleasant music compared with pleasant music, suggesting the involvement of descending pain‐modulatory mechanisms in the effects of musical emotions on pain. There were no significant differences between the pleasant‐stimulating and pleasant‐relaxing musical condition, indicating that the arousal of music had little influence on pain processing.
A compartment‐specific transcriptome analysis reveals survival‐relevant marker genes in the stroma fraction of squamous non‐small cell lung cancer
Authors: Bendrat Klaus , Stang Axel , Georgiev Georgi , Geffers Robert , Haase Bernd , Schütze Karin , Mogilarov Dimitar , Branscheid Detlev , Niendorf Axel
Published: January 2012

Although it is increasingly recognized that the tumor biology is influenced by the tumor stroma, prognostic gene signatures are usually derived from tissue consisting of tumor cells and surrounding stroma. This study presents a compartment‐specific transcriptome analysis of lung squamous cell carcinoma (SCC) samples microdissected into tumor parenchyma and stroma fractions. Typical tumor and stroma genes were identified based on the expression ratios between the two compartments. Our results indicate that in SCC many markers related to longer survival are predominantly expressed in the stroma, particularly genes of the MHC‐II complex. Stromal upregulation of MHC‐II genes seems crucial for a clinically relevant antitumor immune response in SCC. (© 2012 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Fast T1 mapping determined using incomplete inversion recovery look–locker 3D balanced SSFP acquisition and a simple two‐parameter model fit
Authors: Gai Neville D. , Butman John A.
Published: January 2012

Purpose:

To evaluate a fast T1 mapping technique using incomplete inversion recovery 3D balanced steady‐state free precession acquisition along with a two‐parameter model fit.

Materials and Methods:

Using Bloch simulations, we explored the two‐parameter model fit for data acquired using such an acquisition scheme. The parameter space over which the fit holds good was determined through simulations. A linear correction was derived for the R1* (1/T1*) values so determined. Two phantoms and six volunteers were scanned using the described technique. Comparison scans using full recovery as well as gold standard inversion recovery spin echo were also performed.

Results:

The two‐parameter fit works exceedingly well over a large parameter space. T1 values in the phantoms showed an error of 4.9% and 39% before correction and 0.9% and 1.6% after correction. For the six volunteers, error in T1 value was 5.3% for white matter (WM) and 2.4% for gray matter (GM) after correction, while it was 11.2% and 18.2% before correction.

Conclusion:

The work presented here allows for T1 map determination with higher resolution and shorter acquisition time than previously possible. The technique is especially well suited for GM/WM T1 mapping. J. Magn. Reson. Imaging 2012;35:1437–1444. © 2012 Wiley Periodicals Inc.
Analysis of furanocoumarins from Yemenite Dorstenia species by liquid chromatography/electrospray tandem mass spectrometry
Authors: Heinke Ramona , Franke Katrin , Michels Katharina , Wessjohann Ludger , Ali Nasser Abdullah Awadh , Schmidt Jürgen
Published: January 2012

A series of prevailing prenylated furanocoumarins from leaves of Dorstenia gigas and Dorstenia foetida (Moraceae) were investigated by liquid chromatography/electrospray tandem mass spectrometry. The mass spectral behavior of the furanocoumarins under positive ion electrospray conditions is discussed using both an ion trap and a triple quadrupole system. It is demonstrated that both methods represent valuable tools not only for the rapid classification of this type of compounds, but also with respect to their substitution pattern. Copyright © 2012 John Wiley & Sons, Ltd.
Shotgun lipidomics on a LTQ Orbitrap mass spectrometer by successive switching between acquisition polarity modes
Authors: Schuhmann Kai , Almeida Reinaldo , Baumert Mark , Herzog Ronny , Bornstein Stefan R. , Shevchenko Andrej
Published: January 2012

Top–down shotgun lipidomics relies on direct infusion of total lipid extracts into a high‐resolution tandem mass spectrometer and implies that individual lipids are recognized by their accurately determined m/z. Lipid ionization efficiency and detection specificity strongly depend on the acquisition polarity, and therefore it is beneficial to analyze lipid mixtures in both positive and negative modes. Hybrid LTQ Orbitrap mass spectrometers are widely applied in top–down lipidomics; however, rapid polarity switching was previously unfeasible because of the severe and immediate degradation of mass accuracy. Here, we report on a method to rapidly acquire high‐resolution spectra in both polarity modes with sub‐ppm mass accuracy and demonstrate that it not only simplifies and accelerates shotgun lipidomics analyses but also improves the lipidome coverage because more lipid classes and more individual species within each class are recognized. In this way, shotgun analysis of total lipid extracts of human blood plasma enabled to quantify 222 species from 15 major lipid classes within 7 min acquisition cycle. Copyright © 2012 John Wiley & Sons, Ltd.
Rapid and robust confirmation and quantification of 11‐nor‐Δ9‐tetrahydrocannabinol‐9‐carboxylic acid (THC‐COOH) in urine by column switching LC‐MS‐MS analysis
Authors: Zanchetti Gabriele , Floris Ivan , Piccinotti Alberto , Tameni Silvia , Polettini Aldo
Published: January 2012

A method for the rapid and robust confirmation of 11‐nor‐∆9‐tetrahydrocannabinol‐9‐carboxylic acid (THCA) in urine involving basic hydrolysis with NaOH and direct injection of the hydrolysate in a column‐switching LC‐MS‐MS system was developed and validated. THCA‐d3 was used as internal standard. Detection was performed in negative‐ion mode by monitoring the transitions from the [M‐CO2]‐ ion m/z 299.2→245.2 and and m/z 299.2→191.1 that were found to provide a better signal‐to‐noise ratio than the transition from the pseudomolecular ion at m/z 343. The high sensitivity of detection enabled the injection of a small volume (10 µl) of the NaOH hydrolysate which, together with the applied column switching system, proved to confer ruggedness to the method and to avoid the deterioration of the instrumental apparatus despite the large amount of inorganic ions in the hydrolysate. The LLOQ was established at 5 ng/ml, and the LLOD was calculated as 0.2 ng/ml (S/N =3). The method was submitted to thorough validation including evaluation of the calibration range (5–500 ng/ml), accuracy and precision, matrix effects, overall process efficiency, autosampler stability, carryover and cross‐talk, and 10‐times reduction of sample volume (0.1 ml). Proof of applicability was obtained by direct comparison with the reference GC‐MS method in use in the lab (the R2 between the two methods was 0.9951). Copyright © 2012 John Wiley & Sons, Ltd.
Optimizing the osteogenicity of nanotopography using block co‐polymer phase separation fabrication techniques
Authors: Maclaine Sarah E. , Gadhari Neha , Pugin Raphael , Meek Robert M. Dominic , Liley Martha , Dalby Matthew J.
Published: January 2012

Both temporary and permanent orthopedic implants have, by default or design, surface chemistry, and topography. There is increasing evidence that controlling nanodisorder can result in increased osteogenesis. Block co‐polymer phase separation can be used to fabricate a nanotopography exhibiting a controlled level of disorder, both reproducibly and cost‐effectively. Two different topographies, produced through the use of block co‐polymer phase separation, were embossed onto the biodegradable thermoplastic, polycaprolactone (PCL). Analysis of the topography itself was undertaken with atomic force microscopy, and the topography's effect on human osteoblasts studied through the use of immunocytochemistry and fluorescence microscopy. Planar controls had a surface roughness 0.93 nm, and the substrates a high fidelity transfer of a disordered pattern of 14 and 18 nm. Cytoskeletal organization and adhesion, and increased expression of Runx2 were significantly greater on the smallest nanotopography. Expression of osteopontin and osteocalcin protein, and alizarin red staining of bone nodules were greatest on the smallest feature nanopatterns. Highly osteogenic, disordered nanotopographies can be manufactured into thermoplastics in a rapid and cost‐effective way through the use of block co‐polymer phase separation. Osteogenic topographies reproducibly and cost‐effectively produced have a potentially useful application to the fields of implant technology and regenerative orthopedics. © 2012 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 30:1190–1197, 2012
Contemporary perspectives on diversity interventions: A dilemma for educators
Authors: Walton Sean
Published: January 2012

The author considers and contrasts a number of contemporary viewpoints about the nature and potential impact of diversity interventions primarily within higher education institutions and across organizational cultures. He focuses on issues of race and racial inequality, although the principles and theoretical perspectives discussed could be applied to other areas where inequalities exist. The author also draws upon current perspectives on race, racism, and ways of making effective and meaningful diversity interventions, including views from critical pedagogy, critical race theory, and cosmopolitan thinkers. He concludes that the modern educator within higher education is faced with the dilemma of a choice between rejecting useful theoretical insights into the extent of racial discrimination and being resigned to making largely ineffective diversity interventions. A solution to the dilemma is briefly outlined.
Hydrophilic interaction chromatography for the analysis of aminoglycosides
Authors: Kumar Praveen , Rubies Antoni , Companyó Ramon , Centrich Francesc
Published: January 2012

The effect of mobile‐phase constituents (pH and ionic strength) and chromatographic behaviour of ten aminoglycosides (streptomycin, dihydrostreptomycin, spectinomycin, apramycin, paramomycin, kanamycin A, gentamycin C1, gentamycin C2/C2a, gentamycin C1a and neomycin) in the bare silica, amino, amide and zwitterionic phases of hydrophilic interaction chromatography (HILIC) were studied systematically. Among the stationary phases studied, the zwitterionic phase provided the best separation of aminoglycosides. The effect of pH, ionic concentration and column temperature on retention time, peak shape and sensitivity was studied using a central composite design. pH affected sensitivity of the detection of analytes but not the retention time. High ionic strength in the mobile phase was necessary to control the ionic interactions between ionised aminoglycosides and the hydrophilic phase, thereby influencing peak shape and retention time. Column temperature affected sensitivity of the detection but not the retention time. During method development, crosstalk between the MS/MS channels of the analytes was observed and resolved.
Multi‐residue determination of organophosphorus and organochlorine pesticides in environmental samples using solid‐phase extraction with cigarette filter followed by gas chromatography–mass spectrometry
Authors: Fang Guozhen , Chen Wen , Yao Yunping , Wang Junping , Qin Junyan , Wang Shuo
Published: January 2012

A solid‐phase extraction (SPE) method was developed to extract 14 pesticides simultaneously from environment samples using cigarette filter as the sorbent before gas chromatography‐mass spectrometry (GC‐MS) analysis. Parameters influencing the extraction efficiency, such as the sample loading flow rate, eluent and elution volume, were optimized. The optimum sample loading rate was 3 mL/min, and the retained compounds were eluted with 6 mL of eluent at 1 mL/min under vacuum. Good linearity was obtained for all the 14 pesticides (r2>0.99) from 0.1 to 20 μg/L for water and from 2 to 400 μg/kg for soil samples. The detection limits (signal‐to‐noise=3) of the proposed method ranged from 0.01 to 0.20 μg/L for water samples and from 0.42 to 6.95 μg/kg for soil samples. The developed method was successfully applied for determination of the analytes in real environmental samples, and the mean recoveries ranged from 76.4 to 103.7% for water samples and from 79.9 to 105.3% for soil samples with the precisions (relative standard deviation) between 2.0 and 13.6%.
Life history of Tendaguru sauropods as inferred from long bone histology
Authors: Sander P. M.
Published: January 2012

Abstract. Sauropod dinosaurs present exceptional challenges in understanding their biology because of their exceptional body size. One of these, life history, can be inferred from the histology of their bones. For this purpose, the diverse sauropod assemblage of the Upper Jurassic Tendaguru beds was sampled with a new coring method which provided unprecented access to and insights into sauropod bone histology. Growth series of humeri and femora as well as long growth records from single bones suggest that all four sauropod taxa are characterized by continued growth after sexual maturity but that growth was determinate. Fibrolamellär bone is dominant in the samples, indicating that the bones of the Tendaguru sauropods grew at rates comparable to those of modern large mammals. The growth pattern of these sauropods thus combines typically reptilian traits with typically mammalian traits. In the details of their bone histology, the Tendaguru sauropod taxa show considerable variation which reflects life history. In addition, Barosaurus exhibits probable sexual dimorphism in bone histology. Das Verständnis der Biologie der sauropoden Dinosaurier wird durch ihre enorme Körpergröße außerordentlich erschwert. Allerdings kann ein Aspekt, die Lebensgeschichte, anhand der Histologie ihrer Knochen untersucht werden. Zu diesem Zweck wurde die diverse Sauropoden-Vergesellschaftung der oberjurassischen Tendaguru-Schichten beprobt, und zwar mit einer neuartigen Kernbohrmethode, die einen herausragenden Zugang und Einblick in die Knochenhistologie der Sauropoden ermöglichte. Wachstumsserien von Humeri und Femora sowie umfassende Überlieferungen des Wachstums von Individuen anhand einzelner Knochen machen es wahrscheinlich, daß alle vier Sauropoden-Taxa der Tendaguru-Schichten durch ein auch nach der Geschlechtsreife anhaltendes Wachstum gekennzeichnet waren. Allerdings ging das Wachstum nicht bis zum Tode des Tieres weiter, sondern kam bei einer etwas variablen Maximalgröße zum Stillstand. Fibrolamellärer Knochen ist der vorherrschende Knochentyp in den Proben, was anzeigt, daß die Tendaguru-Sauropoden mit für Säugetieren typische Raten wuchsen. Die Tendaguru-Sauropoden kombinerten also ein für Reptilien typisches Muster des Wachstums, nämlich nach der Geschlechtsreife anhaltendes Wachstum, mit für Säuger typischen Raten des Wachstums. Die verschiedenen Sauropoden-Taxa zeigen erstaunliche Unterschiede in den Details ihrer Knochenhistologie, die Unterschiede in der Lebensgeschichte belegen. Bei Barosaurus scheint außerdem ein Geschlechtsdimorphismus in der Histologie der Langknochen vorzukommen. doi:1002/mmng.1999.4860020107
Double pulsed field gradient (double‐PFG) MR imaging (MRI) as a means to measure the size of plant cells
Authors: Özarslan E. , Komlosh M. E. , Lizak M. J. , Horkay F. , Basser P. J.
Published: January 2012

Measurement of diffusion in porous materials and biological tissues with the pulsed field gradient (PFG) MR techniques has proven useful in characterizing the microstructure of such specimens noninvasively. A natural extension of the traditional PFG technique comprises multiple pairs of diffusion gradients. This approach has been shown to provide the ability to characterize anisotropy at different length scales without the need to employ very strong gradients. In this work, the double‐PFG imaging technique was used on a specimen involving a series of glass capillary arrays with different diameters. The experiments on the phantom demonstrated the ability to create a quantitative and accurate map of pore sizes. The same technique was subsequently employed to image a celery stalk. A diffusion tensor image (DTI) of the same specimen was instrumental in accurately delineating the regions of vascular tissue and determining the local orientation of cells. This orientation information was incorporated into a theoretical double‐PFG framework and the technique was employed to estimate the cell size in the vascular bundles of the celery stalk. The findings suggest that the double‐PFG MRI framework could provide important new information regarding the microstructure of many plants and other food products. Copyright © 2012 John Wiley & Sons, Ltd.
NMR on emulsions: characterisation of liquid dispersed systems
Authors: Bernewitz R. , Guthausen G. , Schuchmann H. P.
Published: January 2012

Pulsed field gradient NMR (PFG‐NMR) is an important method for the characterisation of emulsions. Apart from its application in quality control and process development, especially high‐field NMR methods can be applied to investigate emulsions properties on the molecular level. Meanwhile, complex emulsion structures such as double emulsions have been developed and require analytical tools especially for the determination of droplet size distributions. This contribution provides an overview on the possibilities and methods of PFG‐NMR referring to measurement, data processing and interpretation of droplet size distributions. Comparison of techniques and measurements on double emulsions are presented. Copyright © 2012 John Wiley & Sons, Ltd.
A strategy for fast structural elucidation of metabolites in small volume plant extracts using automated MS‐guided LC‐MS‐SPE‐NMR
Authors: van der Hooft Justin J.J. , Mihaleva Velitchka , de Vos Ric C.H. , Bino Raoul J. , Vervoort Jacques
Published: January 2012

In many metabolomics studies, metabolite identification by mass spectrometry (MS) often is hampered by the lack of good reference compounds, and hence, NMR information is essential for structural elucidation, especially for the very large group of secondary metabolites. The classical approach for compound identification is to perform time‐consuming and laborious HPLC fractionations and purifications, before (re)dissolving the molecules in deuterated solvents for NMR measurements. Hence, a more direct and easy purification protocol would save time and efforts. Here, we propose an automated MS‐guided HPLC‐MS‐solid phase extraction‐NMR approach, which was used to fully characterize flavonoid structures present in crude tomato plant extracts. NMR spectra of plant metabolites, automatically trapped and purified from LC‐MS traces, were successfully obtained, leading to the structural elucidation of the metabolites. The MS‐based trapping enabled a direct link between the mass signals and NMR peaks derived from the selected LC‐MS peaks, thereby decreasing the time needed for elucidation of the metabolite structures. In addition, automated 1H NMR spectrum fitting further speeded up the candidate rejection process. Our approach facilitates the more rapid unraveling of yet unknown metabolite structures and can therefore make untargeted metabolomics approaches more powerful. Copyright © 2012 John Wiley & Sons, Ltd.
Enhanced NMR‐based profiling of polyphenols in commercially available grape juices using solid‐phase extraction
Authors: Savage Angela K. , van Duynhoven John P. M. , Tucker Gregory , Daykin Clare A.
Published: January 2012

Grapes and related products, such as juices, and in particular, their polyphenols, have previously been associated with many health benefits, such as protection against cardiovascular disease. Within grapes, a large range of structurally diverse polyphenols can be present, and their characterisation stands as a challenge. 1H NMR spectroscopy in principle would provide a rapid, nondestructive and straightforward method for profiling of polyphenols. However, polyphenol profiling and identification in grape juices is hindered because of signals of prevailing carbohydrates causing spectral overlap and compromising dynamic range. This study describes the development of an extraction method prior to analysis using 1H NMR spectroscopy, which can, potentially, significantly increase the number of detectable polyphenols and aid their identification, by reduction of signal overlap and selective removal of heavily dominating compounds such as sugars. Copyright © 2012 John Wiley & Sons, Ltd.
NMR studies of hydration in low water content biopolymer systems
Authors: Belton Peter S.
Published: January 2012

The problem of characterising the behaviour of water and biopolymers by NMR in low water content biopolymer systems is discussed. A low water content system is defined, and the problems of characterising the relaxation behaviour of the water are analysed. In the case of protons, the types of protons contributing to the signal and the exchange mechanism between them cannot be systematised in terms of existing models that have been developed for high water content systems. It is suggested that any successful model must take account of at least three separate pools of water including water vapour. Experimental results indicate that although the motion of the biopolymer is radically affected by water, the reverse is not necessarily true. It is concluded that the use of nuclei such as 13C and 15N may be very effectively used to characterise biopolymer motion, but the use of both 1H and 2H for characterising water is still problematic. Despite the formidable experimental and theoretical difficulties, 17O NMR may be the only way to finally to untangle the problem. Copyright © 2012 John Wiley & Sons, Ltd.
Anniversary retrospective, perspective and prospective of corporate public affairs: moving from the 2000+ PA Model toward Public Affairs 2.0
Authors: Fleisher Craig
Published: January 2012

The anniversary issue of the Journal of Public Affairs is an appropriate time to reflect on decades of developments in the public affairs field and to put ideas into perspective. In this article, I revisit the paper I wrote for the first edition of this journal in which I tried to describe the state of the art of US public affairs practice under the rubric of the 2000+ PA Model as it existed at the start of the last decade (2001–2010). Much of what was envisioned came to pass, although some elements in greater or lesser fashion will be described. I also provide some perspective on how the PA state of the art will unfold in the current decade (2011–2020), using a model I characterize as Public Affairs 2.0. Copyright © 2012 John Wiley & Sons, Ltd.
Effect of hydroxyurea treatment on renal function parameters: Results from the multi‐center placebo‐controlled BABY HUG clinical trial for infants with sickle cell anemia
Authors: Alvarez Ofelia , Miller Scott T. , Wang Winfred C. , Luo Zhaoyu , McCarville M. Beth , Schwartz George J. , Thompson Bruce , Howard Thomas , Iyer Rathi V. , Rana Sohail R. , Rogers Zora R. , Sarnaik Sharada A. , Thornburg Courtney D. , Ware Russell E. ,   the BABY HUG Investigators
Published: January 2012

Background

Children with sickle cell anemia (SCA) often develop hyposthenuria and renal hyperfiltration at an early age, possibly contributing to the glomerular injury and renal insufficiency commonly seen later in life. The Phase III randomized double‐blinded Clinical Trial of Hydroxyurea in Infants with SCA (BABY HUG) tested the hypothesis that hydroxyurea can prevent kidney dysfunction by reducing hyperfiltration.

Procedure

193 infants with SCA (mean age 13.8 months) received hydroxyurea 20 mg/kg/day or placebo for 24 months. 99mTc diethylenetriaminepentaacetic acid (DTPA) clearance, serum creatinine, serum cystatin C, urinalysis, serum and urine osmolality after parent‐supervised fluid deprivation, and renal ultrasonography were obtained at baseline and at exit to measure treatment effects on renal function.

Results

At exit children treated with hydroxyurea had significantly higher urine osmolality (mean 495 mOsm/kg H2O compared to 452 in the placebo group, P = 0.007) and a larger percentage of subjects taking hydroxyurea achieved urine osmolality >500 mOsm/kg H2O. Moreover, children treated with hydroxyurea had smaller renal volumes (P = 0.007). DTPA‐derived glomerular filtration rate (GFR) was not significantly different between the two treatment groups, but was significantly higher than published norms. GFR estimated by the Chronic Kidney Disease in Children (CKiD) Schwartz formula was the best non‐invasive method to estimate GFR in these children, as it was the closest to the DTPA‐derived GFR.

Conclusion

Treatment with hydroxyurea for 24 months did not influence GFR in young children with SCA. However, hydroxyurea was associated with better urine concentrating ability and less renal enlargement, suggesting some benefit to renal function. (ClinicalTrials.gov number NCT00006400) Pediatr Blood Cancer 2012;59:668–674. © 2012 Wiley Periodicals, Inc.
Outdoor evaluation of concentrator photovoltaic systems modules from different manufacturers: first results and steps
Authors: Fernández Eduardo F. , Pérez‐Higueras Pedro , Garcia Loureiro Antonio J. , Vidal Pedro G.
Published: January 2012

For the behavior of concentrator photovoltaic systems technology under real conditions to be understood, different modules from different manufacturers were measured in a new research center in Jaén. The influence in the power and the efficiency of irradiation levels, air temperature, and the influence of air mass were under study for 6 months. Pmax shows a linear behavior with direct normal irradiance, and efficiency was constant to a first approximation for a wide range of irradiance levels. The effect of air temperature was negligible for the temperatures under study. At the same time, efficiency shows a maximum around AM1.5 and decreases aside this point. Copyright © 2012 John Wiley & Sons, Ltd.
Association between breast cancer and allostatic load by race: National Health and Nutrition Examination Survey 1999–2008
Authors: Parente Victoria , Hale Lauren , Palermo Tia
Published: January 2012

Background

Breast cancer and its treatment introduce numerous physiologic, psychological, social, and economic stressors to a woman with the diagnosis. Allostatic load, a composite score of biomarkers representing physiologic dysregulation, may serve as a measure of the biological burden of breast cancer. This study investigates the association between breast cancer and allostatic load scores by comparing allostatic load scores in those with a history of breast cancer to those without, stratified by race.

Methods

Black and white women aged 35 to 85 were analyzed using the data from NHANES 1999–2008 (n = 4875 women, of which 188 women had a history of breast cancer). Stratified by race, we ran multivariate analyses with history of breast cancer as a predictor for elevated allostatic load while adjusting for other potentially confounding variables.

Results

Although a history of breast cancer was not associated with elevated allostatic load in white women, it was significantly associated with elevated allostatic load in black women after adjusting for age, income, education, insurance type, smoking status, alcohol intake, and physical activity [Odds Ratio (OR) 2.08 (95%CI 1.02, 4.22)]. Furthermore, an interaction between black and having a history of breast cancer was found to be significant in predicting elevated allostatic load scores after adjusting for demographic, behavioral, and comorbidity characteristics.

Conclusions

These results suggest that the biological toll of breast cancer may be greater in black women than white women. Copyright © 2012 John Wiley & Sons, Ltd.
Identification and removal of nitroxide spin label contaminant: Impact on PRE studies of α‐helical membrane proteins in detergent
Authors: Kroncke Brett M. , Columbus Linda
Published: January 2012

NMR paramagnetic relaxation enhancement (PRE) provides long‐range distance constraints (∼15–25 Å) that can be critical to determining overall protein topology, especially where long‐range NOE information is unavailable such as in the case of larger proteins that require deuteration. However, several challenges currently limit the use of NMR PRE for α‐helical membrane proteins. One challenge is the nonspecific association of the nitroxide spin label to the protein‐detergent complex that can result in spurious PRE derived distance restraints. The effect of the nitroxide spin label contaminant is evaluated and quantified and a robust method for the removal of the contaminant is provided to advance the application of PRE restraints to membrane protein NMR structure determination.
Concise guide to the diagnosis and management of osteoarthritis
Authors: Wenham Claire , Conaghan Philip
Published: January 2012

Osteoarthritis results in joint pain and can reduce participation in daily activities. In our Drug review the authors discuss diagnosis and the available management options, followed by an analysis of the prescription data and sources of further information. Copyright © 2012 Wiley Interface Ltd
Bydureon: long‐acting exenatide for once‐weekly injection
Authors: Ballav Chitrabhanu , Gough Stephen
Published: January 2012

Bydureon is a long‐acting formulation of exenatide administered as a once‐weekly injection. The authors present the clinical data relating to its efficacy and adverse effects compared with twice‐daily exenatide and other treatments used in type 2 diabetes and discuss its potential role in management. Copyright © 2012 Wiley Interface Ltd
Schottky barrier and interface chemistry for Ni contacted to Al0.8Ga0.2N grown on c‐oriented AlN single crystal substrates
Authors: Tweedie James , Collazo Ramón , Rice Anthony , Mita Seiji , Xie Jinqiao , Akouala Rajiv‐Christer , Sitar Zlatko
Published: January 2012

We demonstrate electronic sequential tunneling transport through the ground‐state subbands of GaN/Al0.15Ga0.85N quantum cascade structures grown on free‐standing GaN substrates. A pronounced transition from a high‐ to a low‐resistance state is observed as the applied voltage is increased. The measured current‐voltage characteristics are found to vary with temperature, structure design, and polarity of the applied bias, in a way that is fully consistent with theoretical expectations. The dominant transport mechanism is determined to be scattering‐assisted tunneling (© 2012 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Effect of post‐gate RTA on leakage current (Ioff) in GaN MOSHEMTs
Authors: Huang Tongde , Wong Ka Ming , Li Ming , Zhu Xueliang , Lau Kei May
Published: January 2012

Effect of post‐gate rapid thermal annealing (RTA) on GaN metal‐oxide semiconductor high electron mobility transistors (MOSHEMTs) performance has been investigated. For devices with 1‐µm gate length and 10‐µm gate width, a significant reduction of Iofffrom 10‐4 to 10‐6 mA/mm (at Vgs = ‐8 V, Vd= 6 V) was observed after post‐gate RTA at 600 °C, indicating an excellent ON/OFF drain current ratio (Ion/Ioff) up to 108. The reduction of Ioffis mainly dominated by the decreased reverse‐biased gate leakage current, as indicated by the strong dependence of Ion/Ioff on reverse‐biased gate leakage current. The reduced gate leakage after post‐gate RTA probably stems from the increased gate barrier height as a result of gate metal reaction with Al2O3. The degradation in pulse I‐V characteristics may be due to defect formation in devices during post‐gate RTA at 600 °C. Nearly complete recovery was achieved by further post‐gate RTA at 400 °C for 10 minutes. (© 2012 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Growth of InGaN nanowires on a (111)Si substrate by RF‐MBE
Authors: Tabata Takuya , Paek Jihyun , Honda Yoshio , Yamaguchi Masahito , Amano Hiroshi
Published: January 2012

We have grown InGaN nanowires (NWs) on a (111)Si substrate directly by radio‐frequency plasma‐assisted molecular beam epitaxy (RF‐MBE), and investigated their In compositional distribution by energy dispersive x‐ray spectroscopy (EDX). The In composition line profiles of InGaN NWs measured by EDX are different at each position in the InGaN NWs, and In is most easily incorporated into the top of NWs. The In composition at the top of the NWs depends on the growth temperature and the In flux ratio. However, the In compositions at other positions is not dependent on these factors. Thus, these results might be due to the limited diffusion of In atoms from the top of the NWs towards the NWs/Si interface. (© 2012 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Greatly improved crystal quality of non‐polar GaN grown on a‐plane GaN nano‐rod template obtained using self‐organised nano‐masks
Authors: Gong Y. , Xing K. , Bai J. , Wang T.
Published: January 2012

We have developed a simple and effective approach for growth of a‐plane GaN with massively improved crystal quality on a‐plane GaN nanorod template on sapphire. The a‐plane GaN nanorod template is fabricated using self‐organised nickel nano‐masks. X‐ray diffraction rocking curves, measured along both symmetrical and asymmetrical directions, show a massive reduction in full width at half maximum (FWHM), meaning a significant reduction in dislocation density. These are all among best reports although our overgrown layer is only 4‐5 μm, much less than those using any other overgrowth technique. The threading dislocation density has been reduced down to 2.5×108 cm‐2 from typical 9×109 cm‐2 for the a‐plane GaN template on sapphire. The scanning electron microscope measurements show that two kinds of voids have been observed in the cross‐sectional image, which form during the coalescence process of the overgrowth. Taking the advantage of the SiO2 remaining on the top of the nano‐rods, theoretically all dislocations could be effectively blocked. Photoluminescence (PL) measurements have been performed, showing a strong band‐edge emission, which cannot be observed in the a‐plane GaN template on sapphire (© 2012 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
In‐situ void formation technique using an AlN shell structure grown on GaN stripes on Si(111) and c‐plane sapphire substrates
Authors: Mitsunari Tadashi , Tanikawa Tomoyuki , Honda Yoshio , Yamaguchi Masahito , Amano Hiroshi
Published: January 2012

We proposed an in‐situ void formation technique using high‐temperature AlN growth on GaN stripes in order to reduce residual stress. Microcracks were observed during the growth of AlN; the GaN stripes then sublimated from the microcracks while keeping the AlN shell, resulting in void formation in the AlN shell structure. After GaN regrowth on this AlN shell structure, we successfully coalesced the GaN stripes to form a smooth, thick GaN layer having voids at the GaN/substrate interface. Raman spectroscopy confirmed that the residual tensile stress was decreased. The thermal stress decreased owing to the separation between the GaN layer and a foreign substrate. (© 2012 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Accelerating and parallelizing minimizations in ensemble and deterministic variational assimilations
Authors: Desroziers Gérald , Berre Loïk
Published: January 2012

The specification of a correct background‐error covariance matrix is a key issue in data assimilation schemes. The Ensemble Kalman Filter (EnKF) aims at providing simulations of analysis and background errors and then gives a way to determine this background‐error covariance matrix. The EnKF can be transposed to variational ensemble assimilation, where a set of perturbed variational analyses are performed. In this case, however, there is an evident important additional cost associated with the use of multiple minimizations. The aim of the paper is to investigate different techniques to reduce the cost of the multiple minimizations that have to be performed.

In particular, the use is investigated of a preconditioning technique based on Ritz eigenpairs resulting from a first minimization performed by a combined Lanczos/conjugate‐gradient algorithm. The possibility is also studied of improving the starting point of a new perturbed solution, with Lanczos vectors issued from a single prior unperturbed or perturbed minimization. This appears to provide a first significant reduction in the cost of the new minimization.

Finally, a new approach is proposed to generalize the previous idea to the use of multiple sets of Lanczos vectors issued from an ensemble of perturbed assimilations. The application of this procedure to a simplified analysis problem shows encouraging results, as it appears to be a possible way for reducing the global cost of an ensemble variational assimilation. Moreover, this seems to provide an efficient strategy for parallelizing such an ensemble variational assimilation but also the deterministic variational assimilation itself. Copyright © 2012 Royal Meteorological Society
Effect of soft‐storey mechanism caused by infill elimination on displacement demand in nonlinear static procedure using coefficient method
Authors: Alinouri Hossein , Danesh Fakhrodin Ahmadi , Beheshti‐Aval Seyed Bahram
Published: January 2012

In recent earthquakes, many buildings have been damaged due to the soft‐storey mechanism failure. The seismic design codes for buildings do not contain enough criteria to predict the real displacement of such buildings. This paper focuses on evaluating the nonlinear displacement of buildings that fail in soft‐storey mechanism form. Results show that the nonlinear static procedure with coefficient method, which is described in Chapter 3 of ASCE/SEI 41‐06, does not have sufficient accuracy for estimation of structure displacement demand in such buildings. In this paper, the coefficient methodology is used for evaluating the target displacement for 5‐storey, 8‐storey and 15‐storey special moment resisting steel frames. For this purpose, dynamic nonlinear time‐history analysis has been applied for the mentioned structures having a soft‐storey mechanism failure form. The numerical results of storey displacement and interstorey drift were compared with those values obtained from the coefficient method described in Chapter 3 of ASCE/SEI 41‐06. Copyright © 2012 John Wiley & Sons, Ltd.
Differential effects of three professional development models on teacher knowledge and student achievement in elementary science
Authors: Heller Joan I. , Daehler Kirsten R. , Wong Nicole , Shinohara Mayumi , Miratrix Luke W.
Published: January 2012

To identify links among professional development, teacher knowledge, practice, and student achievement, researchers have called for study designs that allow causal inferences and that examine relationships among features of interventions and multiple outcomes. In a randomized experiment implemented in six states with over 270 elementary teachers and 7,000 students, this project compared three related but systematically varied teacher interventions—Teaching Cases, Looking at Student Work, and Metacognitive Analysis—along with no‐treatment controls. The three courses contained identical science content components, but differed in the ways they incorporated analysis of learner thinking and of teaching, making it possible to measure effects of these features on teacher and student outcomes. Interventions were delivered by staff developers trained to lead the teacher courses in their regions. Each course improved teachers' and students' scores on selected‐response science tests well beyond those of controls, and effects were maintained a year later. Student achievement also improved significantly for English language learners in both the study year and follow‐up, and treatment effects did not differ based on sex or race/ethnicity. However, only Teaching Cases and Looking at Student Work courses improved the accuracy and completeness of students' written justifications of test answers in the follow‐up, and only Teaching Cases had sustained effects on teachers' written justifications. Thus, the content component in common across the three courses had powerful effects on teachers' and students' ability to choose correct test answers, but their ability to explain why answers were correct only improved when the professional development incorporated analysis of student conceptual understandings and implications for instruction; metacognitive analysis of teachers' own learning did not improve student justifications either year. Findings suggest investing in professional development that integrates content learning with analysis of student learning and teaching rather than advanced content or teacher metacognition alone. © 2012 Wiley Periodicals, Inc. J Res Sci Teach 49: 333–362, 2012
A new traffic congestion prediction model for advanced traveler information and management systems
Authors: Marfia Gustavo , Roccetti Marco , Amoroso Alessandro
Published: January 2012

The increase of wasted time and pollution due to vehicular traffic has paved the way to many different countermeasures, ranging from the enforcement of congestion tolls to the commercialization of vehicles powered by low‐emission hybrid engines. Advanced traveler information systems (ATISs), which are capable of supplying updated traffic information to all those citizens that are driving through city roads, represent a prominent approach to combat vehicular congestion. In brief, ATISs are concerned with collecting, processing, and disseminating traffic information, providing data that can be profitably exploited by an on‐board navigation system to compute the most convenient route to a given destination. Indeed, their role becomes progressively more relevant as their accuracy and reliability increases, thus encouraging more and more people to utilize them while driving. With this in mind, we devised a new congestion detection model that accurately estimates and forecasts the short‐term congestion state of a road without requiring any prior knowledge regarding any of its parameters. Such model can be easily integrated within an ATIS and usefully applied to any given road. The efficacy of our model is here proved through the results of several experiments, which witness the validity of our approach. Copyright © 2012 John Wiley & Sons, Ltd.
Transcriptional activity of Hyacinthus orientalis L. female gametophyte cells before and after fertilization
Authors: Niedojadło Katarzyna , Pięciński Szymon , Smoliński Dariusz Jan , Bednarska-Kozakiewicz Elżbieta
Published: January 2012

We characterized three phases of Hyacinthus orientalis L. embryo sac development, in which the transcriptional activity of the cells differed using immunolocalization of incorporated 5′-bromouracil, the total RNA polymerase II pool and the hypo- (initiation) and hyperphosphorylated (elongation) forms of RNA Pol II. The first stage, which lasts from the multinuclear stage to cellularization, is a period of high transcriptional activity, probably related to the maturation of female gametophyte cells. The second stage, encompassing the period of embryo sac maturity and the progamic phase, involves the transcriptional silencing of cells that will soon undergo fusion with male gametes. During this period in the hyacinth egg cell, there are almost no newly formed transcripts, and only a small pool of RNA Pol II is present in the nucleus. The transcriptional activity of the central cell is only slightly higher than that observed in the egg cell. The post-fertilization stage is related to the transcriptional activation of the zygote and the primary endosperm cell. The rapid increase in the pool of newly formed transcripts in these cells is accompanied by an increase in the pool of RNA Pol II, and the pattern of enzyme distribution in the zygote nucleus is similar to that observed in the somatic cells of the ovule. Our data, together with the earlier results of Pięciński et al. (2008), indicate post-fertilization synthesis and the maturation of numerous mRNA transcripts, suggesting that fertilization in H. orientalis induces the activation of the zygote and endosperm genomes.
EPA guidance on the quality of mental health services
Authors: Gaebel W. , Becker T. , Janssen B. , Munk-Jorgensen P. , Musalek M. , Rössler W. , Sommerlad K. , Tansella M. , Thornicroft G. , Zielasek J.
Published: January 2012

The main aim of this guidance of the European Psychiatric Association is to provide evidence-based recommendations on the quality of mental health services in Europe. The recommendations were derived from a systematic search of the best available evidence in the scientific literature, supplemented by information from documents retrieved upon reviewing the identified articles. While most recommendations could be based on empirical studies (although of varying quality), some had to be based on expert opinion alone, but were deemed necessary as well. Another limitation was that the wide variety of service models and service traditions for the mentally ill worldwide often made generalisations difficult. In spite of these limitations, we arrived at 30 recommendations covering structure, process and outcome quality both on a generic and a setting-specific level. Operationalisations for each recommendation with measures to be considered as denominators and numerators are given as well to suggest quality indicators for future benchmarking across European countries. Further pan-European research will need to show whether the implementation of this guidance will lead to improved quality of mental healthcare, and may help to develop useful country-specific cutoffs for the suggested quality indicators.
Crystal structure of cce_0566 from Cyanothece 51142, a protein associated with nitrogen fixation in the DUF269 family
Authors: Buchko Garry W. , Robinson Howard
Published: January 2012

DUF269 and DUF269 bind by x‐ray crystallography (View interaction)