bluuebunny/crossref_metadata_2025_split huggingface dataset:
Correlation of volume transfer coefficient Ktrans with histopathologic grades of gliomas
Authors: Zhang Na , Zhang Lijuan , Qiu Bensheng , Meng Li , Wang Xiaoyi , Hou Bob L. 
Published: May 2012

AbstractPurpose:To evaluate the roles of dynamic contrast‐enhanced magnetic resonance imaging (DCE‐MRI) and optimum tracer kinetic parameters in the noninvasive grading of the glial brain tumors with histopathological grades (I–IV).Materials and Methods:Twenty‐eight patients with histopathologically graded gliomas were imaged. Images with five flip angles were acquired before injection of gadolinium‐DTPA and were processed to calculate the T1 value of each region of interest (ROI). All the DCE‐MRI data acquired during the injection were processed based on the MRI signal and pharmacokinetic models to establish concentration–time curves in the ROIs drawn within the tumors, contralateral normal areas, and area of the individual artery input functions (iAIF) of each patient. A nonlinear least‐square‐fitting method was used to obtain tracer kinetic parameters. Kruskal–Wallis H‐test and Mann–Whitney U‐test were applied to these parameters in different histopathological grade groups for statistical differences (P < 0.05).Results:Volume transfer coefficient (Ktrans) and extravascular extracellular space volume fraction (Ve) calculated using iAIFs can be used not only to distinguish the low (ie, I and II) from the high (ie, III and IV) grade gliomas (P() < 0.001 and PVe < 0.001), but also grade II from III (P() = 0.016 and PVe = 0.033).Conclusion:Ktrans is the most sensitive and specific parameter in noninvasive grading, distinguishing the high (III and IV) from the low (I and II) grade and high grade III from low grade II gliomas. J. Magn. Reson. Imaging 2012;36:355–363. © 2012 Wiley Periodicals, Inc.
Reproducibility of single‐subject fMRI language mapping with AMPLE normalization
Authors: Voyvodic James T. 
Published: May 2012

AbstractPurpose:To evaluate the reproducibility of presurgical functional MRI (fMRI) language mapping based on test–retest scans, comparing traditional activation t‐maps to relative activation maps normalized by activation mapping as percentage of local excitation (AMPLE).Materials and Methods:Language fMRI scans were performed by 12 healthy volunteer subjects undergoing a standard clinical presurgical mapping protocol in multiple independent scan sessions. Objective relative AMPLE activation maps were generated automatically by normalizing statistical t‐value maps to the local peak activation amplitude within each functional brain region. The spatial distribution of activation was quantified and compared across mapping algorithms, subjects, scanners, and pulse sequences.Results:The spatial distribution of traditional blood oxygen level‐dependent (BOLD) t‐value statistical activation maps was highly variable in test–retest scans of single subjects, whereas AMPLE normalized maps were highly reproducible in terms of the location, hemispheric laterality, and spatial extent of relative activation. AMPLE map reproducibility was good regardless of scanner, field strength, or pulse sequence used, but reproducibility was best for scans acquired on the same scanner using the same pulse sequence.Conclusion:Reproducibility of the spatial pattern of BOLD activation makes relative amplitude fMRI mapping a useful normalization tool for clinical imaging of language function, where reproducibility and quantitative measurements are critical concerns. J. Magn. Reson. Imaging 2012;36:569–580. © 2012 Wiley Periodicals, Inc.
Microtubule and male sterility in a gene‐cytoplasmic male sterile line of non‐heading Chinese cabbage
Authors: Zhang Jingyi , Zhang Changwei , Cheng Yan , Qi Li , Wang Shumin , Hou Xilin 
Published: May 2012

AbstractBACKGROUND: Microtubules are the basic components of the cytoskeleton in eukaryotic cells and are made up of 13 parallel protofilaments, each composed of α‐ and β‐tubulin unit molecules aligned along the longitudinal axis of the microtubule.RESULTS: α‐Tubulin gene TUBA2 from non‐heading Chinese cabbage (Brassica campestris ssp. chinensis Makino) was expressed at the highest level in stamens and at lower levels in other organs. In addition, it was expressed at a much lower level in the cytoplasmic male sterile (CMS) line than in the maintainer line. Furthermore, at the microsporocyte stage of development in the CMS line the microtubule bundles were knitted together in random organisation, which differed significantly from the radiate microtubule bundles running circumferentially around the nucleus in the maintainer line. Also, large vacuoles appeared within the cytoplasm in the CMS line with no dyed microtubules.CONCLUSION: TUBA2 was very important to pollen development, which might be closely related to male sterility. Large vacuoles might replace the nuclei close to the cell walls and lead to a lack of microtubules when the cells abort. Abnormalities and defects in the organisation and composition of microtubules in the male sterile line highlighted the complex interaction between microtubules and cytoplasmic male sterility. Copyright © 2012 Society of Chemical Industry
Lipids and human milk
Authors: Kim Jongsoo , Friel James 
Published: May 2012

AbstractTo support the growth and development of the breast‐fed infant, human milk provides the dietary essential fatty acids, linoleic acid (LA; 18:2n‐6), α‐linolenic acid (ALA, 18:3n‐3), as well as longer‐chain polyunsaturated fatty acids including arachidonic acid (20:4n‐6) and docosahexanoic (DHA 22:6n‐3). The linoleic acid, alpha‐linolenic acid, DHA and arachidonic acid concentration of pasteurized and unpasteurized human milk remains stable during the first month of storage at –20°C and –80°C. However after the first month, a slow decrease in concentration progresses until the end of 6 months of storage at both temperatures. The levels of n‐6 and n‐3 fatty acids, particularly linoleic acid, alpha‐linolenic acid and DHA, in human milk vary widely within and among different populations, and are readily changed by maternal dietary intake of the respective fatty acid. The present paper reviews recent understanding from key researchers of maternal diet and human milk fat composition and form our work the effect of milk fat composition on storage conditions. It is important to understand that maternal diet can affect human milk fat composition and subsequently infant development and growth.
Existence of solutions for degenerate elliptic equations with singular potential on conical singular manifolds
Authors: Chen Hua , Wei Yawei , Zhou Bin 
Published: May 2012

AbstractIn this work, we study the Dirichlet problem for a class of degenerate elliptic equations with singular potential on conical singular manifolds. By using the cone Sobolev inequality and Hardy inequality, the existence of nontrivial solutions has been proved.
Radial positive definite functions and spectral theory of the Schrödinger operators with point interactions
Authors: Goloshchapova N. , Malamud M. , Zastavnyi V. 
Published: May 2012

AbstractWe complete the classical Schoenberg representation theorem for radial positive definite functions. We apply this result to study spectral properties of self‐adjoint realizations of two‐ and three‐dimensional Schrödinger operators with point interactions on a finite set. In particular, we prove that any realization has purely absolute continuous nonnegative spectrum.
Artificial Leaves via Reproduction of Hierarchical Structures by a Fast Molding and Curing Process
Authors: Park Sungjune , van Rijn Patrick , Böker Alexander 
Published: May 2012

AbstractIn this work, we have developed a practical approach for the replication of hierarchical structures on a native leaf surface via a fast two‐step molding process combining both the fast curability to prevent shrinkage of cells and the strong resistance to chemical compounds for further applications. The negative replica of the leaf was produced from perfluoropolyether (PFPE) by precise molding followed by a fast curing with UV. A liquid ceramic precursor material (polyvinylsilazane, PVSZ) was used to fabricate the positive leaf structure through the same process as applied for the negative imprint of the surface yielding a highly detailed replica of the native leaf surface structure. Static water contact angle measurements show that the biomimetic surfaces exhibit a wettability similar to the native leaves.
A Narrative Review of Evidence‐Based Recommendations for the Physical Examination of the Lumbar Spine, Sacroiliac and Hip Joint Complex
Authors: Wong C. K. , Johnson E. K. 
Published: May 2012

AbstractNon‐specific low back pain is a frequent complaint in primary care, but the differential diagnosis for low back pain can be complex. Despite advances in diagnostic imaging, a specific pathoanatomical source of low back pain can remain elusive in up to 85% of individuals. Best practice guidelines recommend that clinicians conduct a focused physical examination to help to identify patients with non‐specific low back pain and an evidence‐based course of clinical management. The use of sensitive and specific clinical methods to assess the lumbar spine, sacroiliac and hip joints is critical for effective physical examination. Psychosocial factors also play an important role in the evaluation of individuals with low back pain, but are not included in this narrative review of physical examination methods. Physical examination of the lumbar spine, sacroiliac and hip joints is presented, organized around patient position for efficient and effective clinical assessment. Copyright © 2012 John Wiley & Sons, Ltd.
Mit Hochdurchsatz auf der Suche nach neuen Katalysatoren
Authors: Klemm Sebastian , Fink Nicole , Mayrhofer Karl 
Published: May 2012

AbstractDie Umwandlung von CO2 in Energieträger wie Methanol ist eine moderne Dream Reaction — also eine der Reaktionen, die einfach und mit billigen Edukten in einem Schritt, unter milden Bedingungen und in hohen Ausbeuten hochwertige Produkte erzeugen. Mikroelektrochemisches Screening gekoppelt mit Online‐Produktanalyse soll helfen, Katalysatoren für die CO2‐Reduktion zu finden.
Zwischen Wissenschaft und Verwaltung
Authors: Häckel Marko 
Published: May 2012

AbstractUniversitäten und Forschungsinstitute stehen unter dem Druck, ihre Verwaltungen weiter zu professionalisieren, um ihren Aufgaben in Forschung und Lehre gerecht zu werden. Daraus hat sich ein neues Berufsfeld entwickelt: Forschungsmanagement.
Recherchieren, organisieren, verhandeln
Authors: Gottardi Elvira 
Published: May 2012

AbstractEine Tätigkeit im Wissenschaftsmanagement ist nur wenigen Chemiestudenten präsent, wenn sie an Berufseinstieg und Karriere denken. Das war bei Elvira Gottardi nicht anders. Heute unterstützt sie als wissenschaftliche Referentin den Präsidenten der Leibniz‐Gemeinschaft dabei, Strategien zu entwerfen.
Effectiveness of percutaneous posterior tibial nerve stimulation for overactive bladder: A systematic review and meta‐analysis
Authors: Burton C. , Sajja A. , Latthe P.M. 
Published: May 2012

AbstractAimTo evaluate the effectiveness of posterior percutaneous tibial nerve stimulation (PTNS) in treating overactive bladder (OAB) symptoms by systematic review of the literature.MethodsSystematic literature search was carried out (up to April 2011) using relevant search terms in Medline, EMBASE, CINAHL, CENTRAL, National Library for Health, MetaRegister of controlled trials, LILACS, and Google Scholar. Relevant randomized controlled trials (RCTs) and prospective studies were selected and then analyzed by two‐independent reviewers. Meta‐analysis was performed with random effects model using STATA 8 for non‐randomized prospective studies and with Review Manager 5.1 for RCTs.ResultsThe studies report variable initial success rates (37–82%) for treating OAB symptoms with PTNS. Four randomized trials compared PTNS with Sham treatment showing a significant difference favoring PTNS [RR 7.02 95% confidence interval (CI) 1.69–29.17]. Two randomized trials compared PTNS with antimuscarinic medication with no significant difference in the change in bladder diary parameters between the treatments. Ten prospective non‐randomized studies were included. The definitions of success were varied. The pooled subjective success rate was 61.4% (95% CI 57.5–71.8) and objective success rate was 60.6% (95% CI 49.2–74.7).ConclusionThere is evidence of significant improvement in OAB symptoms using PTNS which is comparable to the effect of antimuscarinics but with a better side effect profile. The studies included in the review only considered short‐term outcomes after initial treatment. In order to recommend PTNS as a practical treatment option, long‐term data and health economic analysis are needed. Neurourol. Urodynam. 31:1206–1216, 2012. © 2012 Wiley Periodicals, Inc.
Uniformly stable rectangular elements for fourth order elliptic singular perturbation problems
Authors: Wang Li , WU Yongke , Xie Xiaoping 
Published: May 2012

AbstractIn this article, we consider rectangular finite element methods for fourth order elliptic singular perturbation problems. We show that the non‐ C0 rectangular Morley element is uniformly convergent in the energy norm with respect to the perturbation parameter. We also propose a C0 extended high order rectangular Morley element and prove the uniform convergence. Finally, we do some numerical experiments to confirm the theoretical results. © 2012 Wiley Periodicals, Inc. Numer Methods Partial Differential Eq, 2013
Violence in the Central Iberian Peninsula during the Bronze Age: A Possible Prehistoric Homicide
Authors: JiméNez‐Brobeil S. A. , Roca M. G. , Laffranchi Z. , NáJera T. , Molina F. 
Published: May 2012

ABSTRACTOne of the most interesting sites of the Bronze Age in the central area of the Iberian Peninsula is La Motilla del Azuer (Daimiel, Ciudad Real), dated between 2200 and 1350 bc. The main objective of this study was to investigate interpersonal violence in this site and to report an uncommon case of violent death. No traumatic injury was detected in any child, and men and women significantly differed in the frequency of traumas. More traumatisms were found in men from the earlier stages of occupation, including a young man with at least three blunt force traumas and 26 sharp force traumas. The archaeological findings and trauma patterns in the skeletons of the 65 individuals studied suggest a relatively intense level of exposure to violence for adult men in the earlier stages of occupation of this settlement. Copyright © 2012 John Wiley & Sons, Ltd.
Estimation of the Original Number of Individuals Using Multiple Skeletal Elements
Authors: Nikita E. 
Published: May 2012

ABSTRACTThe current report presents simple equations for the estimation of the original number of individuals that have been preserved in a sample of commingled remains and compares the estimates obtained by them to those obtained from the application of the joint hypergeometric estimator, elaborate computer simulations and documented collections. The equations that perform better under different preservation scenarios are the ones that take into consideration that the various bone types have different post mortem survival probabilities. Copyright © 2012 John Wiley & Sons, Ltd.
Further evidence of impaired position sense in knee osteoarthritis
Authors: Marks R 
Published: May 2012

AbstractThe knee joint position sense of a control group of healthy women was compared with that of women diagnosed as having severe osteoarthritis (OA) of the knee. Movements monitored were multi‐joint when weightbearing on one leg. All subjects completed two angle rematching tests on two separate test occasions, and the criterion and reproduction angles which lay in the range of 15–45° knee flexion were recorded photographically on each occasion. The results showed that the OA group performed the rematching tests with less accuracy than the controls (p<0.05). Additionally, the OA group displayed significantly higher average flexion error magnitudes than the controls. These results suggest that joint position sense is less accurate and may be systematically distorted during multi‐joint movements of the affected legs of a high proportion of women with severe knee OA. They further suggest that to improve their functional performance, patients with knee OA probably require a carefully constructed sensorimotor rehabilitation programme in which pain, effusion and fatigue are minimised.
Sequential four‐state folding/unfolding of goat α‐lactalbumin and its N‐terminal variants
Authors: Tomoyori Katsuaki , Nakamura Takashi , Makabe Koki , Maki Kosuke , Saeki Kimiko , Kuwajima Kunihiro 
Published: May 2012

AbstractEquilibria and kinetics of folding/unfolding of α‐lactalbumin and its two N‐terminal variants were studied by circular dichroism spectroscopy. The two variants were wild‐type recombinant and Glu1‐deletion (E1M) variants expressed in Escherichia coli. The presence of an extra methionine at the N terminus in recombinant α‐lactalbumin destabilized the protein by 2 kcal/mol, while the stability was recovered in the E1M variant in which Glu1 was replaced by Met1. Kinetic folding/unfolding reactions of the proteins, induced by stopped‐flow concentration jumps of guanidine hydrochloride, indicated the presence of a burst‐phase in refolding, and gave chevron plots with significant curvatures in both the folding and unfolding limbs. The folding‐limb curvature was interpreted in terms of accumulation of the burst‐phase intermediate. However, there was no burst phase observed in the unfolding kinetics to interpret the unfolding‐limb curvature. We thus assumed a sequential four‐state mechanism, in which the folding from the burst‐phase intermediate takes place via two transition states separated by a high‐energy intermediate. We estimated changes in the free energies of the burst‐phase intermediate and two transition states, caused by the N‐terminal variations and also by the presence of stabilizing calcium ions. The Φ values at the N terminus and at the Ca2+‐binding site thus obtained increased successively during folding, demonstrating the validity of the sequential mechanism. The stability and the folding behavior of the E1M variant were essentially identical to those of the authentic protein, allowing us to use this variant as a pseudo‐wild‐type α‐lactalbumin in future studies. Proteins 2012; © 2012 Wiley Periodicals, Inc.
Atmospheric water‐vapour profiling from passive microwave sounders over ocean and land. Part I: Methodology for the Megha‐Tropiques mission
Authors: Aires Filipe , Bernardo Frédéric , Prigent Catherine 
Published: May 2012

AbstractA water‐vapour retrieval algorithm has been developed that uses satellite observations in the microwave region. It is based on neural‐network modelling and includes a dedicated calibration scheme for the satellite observations. The water vapour is retrieved for clear and cloudy scenes, over both ocean and land surfaces. Precipitation cases are excluded. The atmospheric relative humidity profile is retrieved on six atmospheric layers, together with the total column water vapour. By‐products are also retrieved by the algorithm, including surface temperature and microwave emissivities over the continents and surface wind speed over the ocean. A first version of a retrieval chain has been produced for the French–Indian Megha‐Tropiques mission launched on 12 October 2011. The algorithm has been further developed for the instruments AMSR‐E/HSB (resp. AMSU‐A/MHS) on board the AQUA (resp. MetOp) platform, in order to test it on existing satellite observations. In this article, the principles of the inversion method are presented and the theoretical retrieval uncertainties are assessed using direct tests on simulated data as well as estimations using the traditional information‐content analysis. Results of the retrieval algorithm will be evaluated in a companion article for AQUA and MetOp observations using comparisons with European Centre for Medium‐Range Weather Forecasts (ECMWF) analysis and radiosonde measurements. Copyright © 2012 Royal Meteorological Society
Error covariance sensitivity and impact estimation with adjoint 4D‐Var: theoretical aspects and first applications to NAVDAS‐AR
Authors: Daescu Dacian N. , Langland Rolf H. 
Published: May 2012

AbstractThis article presents the adjoint‐data assimilation system (adjoint‐DAS) approach to evaluate the forecast sensitivity with respect to the specification of the observation‐error covariance (R‐sensitivity) and background‐error covariance (B‐sensitivity) in a four‐dimensional variational (4D‐Var) DAS with a single outer‐loop iteration. Computationally efficient estimates to the forecast impact of adjustments in the error covariance models are obtained by exploiting the mathematical properties of the R‐ and B‐sensitivity matrices and their relationship with the observation sensitivity vector. An additional contribution of this work is that it establishes a synergistic link between various methodologies to analyze the DAS performance: observation sensitivity and impact assessment, error covariance sensitivity, and a posteriori diagnosis. The practical ability to obtain sensitivity information with respect to R‐ and B‐parameters is presented with the adjoint versions of the Naval Research Laboratory Atmospheric Variational Data Assimilation System–Accelerated Representer (NAVDAS‐AR) and the Navy Operational Global Atmospheric Prediction System (NOGAPS). The adjoint approach is used to provide guidance on the forecast impact of weighting the radiance data in the DAS according to observation‐error variance estimates derived from an a posteriori diagnosis. The results indicate that information extracted from both error covariance diagnosis and sensitivity analysis is necessary to design parameter tuning procedures that are effective in reducing the forecast errors. Copyright © 2012 Royal Meteorological Society
Surface pressure record of Tibetan Plateau warming since the 1870s
Authors: Moore G. W. K. 
Published: May 2012

AbstractThe Tibetan Plateau (TP) is the world's highest and largest plateau. By acting as an elevated thermal source as well as a topographic barrier, the TP has a profound impact on both local weather and global climate. The TP has recently been warming at a faster rate than the entire Northern Hemisphere. However, the lack of instrumental records prior to the 1950s limits our ability to place this recent warming in a longer‐term context. Here we show that over the plateau, because of its high elevation, the surface pressure is a proxy for surface air temperature and that since the 1870s there has been a statistically significant increase in surface pressure over the TP, that has undergone an acceleration since the 1980s. There is also a compensatory decrease in surface pressure in the surrounding lower elevation region. Furthermore, we show that since the 1870s the surface pressure over the plateau is correlated with the Northern Hemisphere temperature record at a statistical significance that exceeds the 99 percentile. Finally, the trend in surface pressure over the plateau is consistent with an increase in annual mean surface air temperature of ∼0.4°C since the 1870s and an increase of ∼1°C since the 1980s. The long‐term warming over the TP derived from the surface pressure trend is of the same order as the long‐term hemispheric warming. This suggests that the increased rate of warming recently observed over the plateau is not a long‐term phenomenon. Copyright © 2012 Royal Meteorological Society