bluuebunny/crossref_metadata_2025_split huggingface dataset:
Ti–Si–C–N thin films grown by reactive arc evaporation from Ti3SiC2 cathodes
Authors: Eriksson Anders O. , Zhu Jianqiang , Ghafoor Naureen , Jensen Jens , Greczynski Grzegorz , Johansson Mats P. , Sjölen Jacob , Odén Magnus , Hultman Lars , Rosén Johanna 
Published: March 2011

Abstract
Targeting the Phosphatidylinositol 3-Kinase Signaling Pathway in Breast Cancer
Authors: Hernandez-Aya Leonel F. , Gonzalez-Angulo Ana M. 
Published: March 2011

Abstract

Learning Objectives
After completing this course, the reader will be able to: Describe how PTEN loss, PIK3CA mutations, and AKT dysregulation affect the phosphatidylinositol 3-kinase (PI3K)/AKT/mammalian target of rapamycin (mTOR) signaling network in human breast cancer.Review the current state of AKT and mTOR inhibitor development, and describe its potential for clinical applications.
This article is available for continuing medical education credit at CME.TheOncologist.com
The phosphatidylinositol 3-kinase (PI3K)/AKT/mammalian target of rapamycin (mTOR) network plays a key regulatory function in cell survival, proliferation, migration, metabolism, angiogenesis, and apoptosis. Genetic aberrations found at different levels, either with activation of oncogenes or inactivation of tumor suppressors, make this pathway one of the most commonly disrupted in human breast cancer. The PI3K-dependent phosphorylation and activation of the serine/threonine kinase AKT is a key activator of cell survival mechanisms. The activation of the oncogene PIK3CA and the loss of regulators of AKT including the tumor suppressor gene PTEN are mutations commonly found in breast tumors. AKT relieves the negative regulation of mTOR to activate protein synthesis and cell proliferation through S6K and 4EBP1. The common activation of the PI3K pathway in breast cancer has led to the development of compounds targeting the effector mechanisms of the pathway including selective and pan-PI3K/pan-AKT inhibitors, rapamycin analogs for mTOR inhibition, and TOR-catalytic subunit inhibitors. The influences of other oncogenic pathways such as Ras-Raf-Mek on the PI3K pathway and the known feedback mechanisms of activation have prompted the use of compounds with broader effect at multiple levels and rational combination strategies to obtain a more potent antitumor activity and possibly a meaningful clinical effect. Here, we review the biology of the network, its role in the development and progression of breast cancer, and the evaluation of targeted therapies in clinical trials.
Internal Fixation of Type-C Distal Femoral Fractures in Osteoporotic Bone
Authors: Mückley Thomas , Wähnert Dirk , Hoffmeier Konrad L. , von Oldenburg Geert , Fröber Rosemarie , Hofmann Gunther O. 
Published: March 2011

BACKGROUND:
Fixation of distal femoral fractures remains a challenge, especially in osteoporotic bone. This study was performed to investigate the biomechanical stability of four different fixation devices for the treatment of comminuted distal femoral fractures in osteoporotic bone.

METHODS:
Four fixation devices were investigated biomechanically under torsional and axial loading. Three intramedullary nails, differing in the mechanism of distal locking (with two lateral-to-medial screws in one construct, one screw and one spiral blade in another construct, and four screws [two oblique and two lateral-to-medial with medial nuts] in the third), and one angular stable plate were used. All constructs were tested in an osteoporotic synthetic bone model of an AO/ASIF type 33-C2 fracture. Two nail constructs (the one-screw and spiral blade construct and the four-screw construct) were also compared under axial loading in eight pairs of fresh-frozen human cadaveric femora.

RESULTS:
The angular stable plate constructs had significantly higher torsional stiffness than the other constructs; the intramedullary nail with four-screw distal locking achieved nearly comparable results. Furthermore, the four-screw distal locking construct had the greatest torsional strength. Axial stiffness was also the highest for the four-screw distal locking device; the lowest values were achieved with the angular stable plate. The ranking of the constructs for axial cycles to failure was the four-screw locking construct, with the highest number of cycles, followed by the angular stable plate, the spiral blade construct, and two-screw fixation. The findings in the human cadaveric bone were comparable with those in the synthetic bone model. Failure modes under cyclic axial load were comparable for the synthetic and human bone models.

CONCLUSIONS:
The findings of this study support the concept that, for intramedullary nails, the kind of distal interlocking pattern affects the stabilization of distal femoral fractures. Four-screw distal locking provides the highest axial stability and nearly comparable torsional stability to that of the angular stable plate; the four-screw distal interlocking construct was found to have the best combined (torsional and axial) biomechanical stability.

CLINICAL RELEVANCE:
The enhanced distal interlocking stability of the four-screw distal locking construct may be beneficial to the stabilization of complex distal femoral fractures, especially in osteoporotic bone.

ORIGINAL ABSTRACT CITATION:
“Internal Fixation of Type-C Distal Femoral Fractures in Osteoporotic Bone” (2010;92:1442-52).
Use of 2-aminoprop-1-ene-1,1,3-tricarbonitrile for the synthesis of tetrahydronaphthalene, hexahydroisoquinoline and hexahydrocinnoline derivatives with potential antitumor activities
Authors: Mohareb Rafat , Moustafa Hosam 
Published: March 2011

Use of 2-aminoprop-1-ene-1,1,3-tricarbonitrile for the synthesis of tetrahydronaphthalene, hexahydroisoquinoline and hexahydrocinnoline derivatives with potential antitumor activities
The aim of the work was to synthesize heterocyclic compounds from 2-aminoprop-1-ene-1,1,3-tricarbonitrile and to study their antitumor activities. The title reagent reacted with cyclohexanone to give the ethylidene derivative 2. The reactivity of the latter product towards different chemical reagents was studied to give tetrahydronaphthalene, hexahydroisoquinoline and hexahydrocinnoline derivatives. The newly synthesized products were screened as antitumor agents on the in vitro growth of three human tumor cell lines representing different tumor types, namely, breast adenocarcinoma (MCF-7), non-small cell lung cancer (NCI-H460) and CNS cancer (SF-268). It was found that some of these compounds showed inhibitory effects on the three cell lines, indicating their potential use in the development of oncology products.
Development of hydroxyapatite-ciprofloxacin bone-implants using »Quality by design«
Authors: Nayak Amit , Laha Bibek , Sen Kalyan 
Published: March 2011

Development of hydroxyapatite-ciprofloxacin bone-implants using »Quality by design«The present study deals with the development of hydroxyapatite (HAp)-ciprofloxacin bone-implants using the »Quality by design« approach. The effect of various synthesis parameters like drug amount added in the process, stirring speed and addition rate of orthophosphoric acid in the synthesis on drug concentration in the HAp-ciprofloxacin system synthesized by the precipitation technique using 23factorial design was analyzed. Optimization methodology utillizing the first-order polynomial equation was used to search for optimal drug concentration in the HAp-ciprofloxacin implant system. The observed responses coincided well with the predicted values from the optimization technique. New implants were manufactured using various HAp-ciprofloxacin composites and 1.5 % (m/V) guar gum as a binder. Characterization of the delivery system was done by XRPD, FTIR spectroscopy and SEM. Even at highest drug concentration (76.6 ± 0.5 %,m/m), ciprofloxacin was present in noncrystalline state. Thein vitrociprofloxacin release from various bone-implants was sustained for several weeks and the drug release pattern correlated well with the Korsmeyer- Peppas model.
Simultaneous spectrophotometric determination of valsartan and hydrochlorothiazide by H-point standard addition method and partial least squares regression
Authors: Lakshmi Karunanidhi , Lakshmi Sivasubramanian 
Published: March 2011

Simultaneous spectrophotometric determination of valsartan and hydrochlorothiazide by H-point standard addition method and partial least squares regression
Simultaneous determination of valsartan and hydrochlorothiazide by the H-point standard additions method (HPSAM) and partial least squares (PLS) calibration is described. Absorbances at a pair of wavelengths, 216 and 228 nm, were monitored with the addition of standard solutions of valsartan. Results of applying HPSAM showed that valsartan and hydrochlorothiazide can be determined simultaneously at concentration ratios varying from 20:1 to 1:15 in a mixed sample. The proposed PLS method does not require chemical separation and spectral graphical procedures for quantitative resolution of mixtures containing the titled compounds. The calibration model was based on absorption spectra in the 200-350 nm range for 25 different mixtures of valsartan and hydrochlorothiazide. Calibration matrices contained 0.5-3 μg mL-1 of both valsartan and hydrochlorothiazide. The standard error of prediction (SEP) for valsartan and hydrochlorothiazide was 0.020 and 0.038 μg mL-1, respectively. Both proposed methods were successfully applied to the determination of valsartan and hydrochlorothiazide in several synthetic and real matrix samples.
Simultaneous determination of iron and copper in children's sera by FAAS
Authors: Luterotti Svjetlana , Kordić Tončica , Dodig Slavica 
Published: March 2011

Simultaneous determination of iron and copper in children's sera by FAASA new and simple flame atomic-absorption spectrometric (FAAS) method is proposed for simultaneous determination of iron and copper in children's sera. It is based on single-step sample pretreatment (deproteinization with 3 mol L-1HCl, ratio 1:1) and single-step calibration using 1.5 mol L-1HCl standard. During method's optimization a short multifactorial design experiment was used. The proposed method assures accuracy, sensitivity and precision comparable to that of the reference methods. The new approach is simple and time-, labour- and serum-saving, the latter being especially important in pediatric diagnostics.
Structural and magnetic properties of ternary Fe1–xMnxPt nanoalloys from first principles
Authors: Gruner Markus E , Entel Peter 
Published: March 2011

Background: Structural and magnetic properties of binary Mn–Pt and ternary Fe1–xMnxPt nanoparticles in the size range of up to 2.5 nm (561 atoms) have been explored systematically by means of large scale first principles calculations in the framework of density functional theory. For each composition several magnetic and structural configurations have been compared.Results: The concentration dependence of magnetization and structural properties of the ternary systems are in good agreement with previous bulk and thin film measurements. At an intermediate Mn-content around x = 0.25 a crossover between several phases with magnetic and structural properties is encountered, which may be interesting for exploitation in functional devices.Conclusion: Addition of Mn effectively increases the stability of single crystalline L10 particles over multiply twinned morphologies. This, however, compromises the stability of the ferromagnetic phase due to an increased number of antiferromagnetic interactions. The consequence is that only small additions of Mn can be tolerated for data recording applications.
γδT cells in Juvenile Idiopathic Arthritis: Higher Percentages of Synovial Vδ1+ and Vγ9+ T Cell Subsets Are Associated with Milder Disease
Authors: BERKUN YACKOV , BENDERSKY ANNA , GERSTEIN MAYA , GOLDSTEIN ITAMAR , PADEH SHAI , BANK ILAN 
Published: March 2011

Objective.To analyze γδT cell subsets in peripheral blood (PB) and synovial fluid (SF) of patients with juvenile idiopathic arthritis (JIA), and to correlate γδT cell subsets with clinical characteristics.Methods.γδT cell subsets as percentages of CD3+ T cells in samples of PB (n = 25) and SF (n = 93) were analyzed by flow cytometry in 93 JIA patients. The percentage of Vγ9+ γδT cells after 10 days ofin vitroexpansion with either interleukin 2 (IL-2) or isopentenyl pyrophosphate (IPP) plus IL-2 was determined.Results.Both Vδ1+ and Vγ9+ γδT cell subsets were detected in SF of all patients, but only the percentage of Vδ1+ cells was higher in SF compared to PB (p < 0.01). The distribution of γδT cell subsets was similar in different JIA subgroups, whereas antinuclear antibody (ANA)-positive patients had a higher percentage of SF Vδ1+ T cells than ANA-negative patients (p < 0.01). The percentage of SF Vδ1+ T cells was inversely associated with age at onset, recurrence of synovitis, and erythrocyte sedimentation rate; and that of SF Vγ9+ T cells was inversely correlated with age at onset and was higher in patients who recovered from disease (n = 15). IPP-induced expansion of SF Vγ9+ T cells correlated with disease remission, whereas the expansion of SF Vγ9+ T cells in media with IL-2 alone was significantly greater in patients with uveitis.Conclusion.The percentage of Vδ1+ and Vγ9+ γδT cells among the SF T cells and their ability to respond to IPP or IL-2 correlated with specific outcomes of JIA, suggesting their role in the immunopathogenesis of this disease.
Prevalence of and Factors Associated with Hypertension in Young and Old Women with Systemic Lupus Erythematosus
Authors: SABIO JOSÉ MARIO , VARGAS-HITOS JOSÉ ANTONIO , NAVARRETE-NAVARRETE NURIA , MEDIAVILLA JUAN DIEGO , JIMÉNEZ-JÁIMEZ JUAN , DÍAZ-CHAMORRO ANTONIO , JIMÉNEZ-ALONSO JUAN 
Published: March 2011

Objective.Hypertension (HT) is more prevalent in patients with systemic lupus erythematosus (SLE) than among the general population and it has been associated with atherosclerotic cardiovascular diseases in these patients. We examined the proportion of HT and factors associated with it in young and old women with SLE.Methods.Participants (112 women with SLE and 223 healthy age-matched women) were categorized as young (age ≤ 40 years) or old (age > 40 years). We compared cardiovascular and specific SLE-related variables and inflammatory markers in hypertensive and normotensive women with SLE for each age range. We also assessed the factors independently associated with HT in the entire cohort and in each age range by means of a multivariate regression analysis.Results.The prevalence of HT was higher in women with SLE than in controls (56% vs 29%; p < 0.001), and was proportionally higher in younger women with SLE (40% vs 11%; p < 0.001) than in older women with SLE (74% vs 47%; p = 0.001). After adjustment for potential confounders, HT was associated with renal involvement and higher nonobesity-related insulin levels in younger women with SLE. In older patients, HT was associated with age, renal involvement, and obesity. Finally, in the entire cohort, HT was associated with age, insulin, renal involvement, and the Systemic Lupus Erythematosus Disease Activity Index score.Conclusion.An association between HT and insulin has been identified in women with SLE, particularly younger ones. Factors associated with HT in women with SLE differed depending on their age. HT was more prevalent in women with SLE than in control subjects, being proportionally higher in young women with SLE.
Trois petits tours et puis s'en va...
Authors: Fertikh Karim 
Published: March 2011

Résumé Bad Godesberg (1959) serait pour le marxisme du SPD le moment d'une mort sans phrase dans un programme qui ne fait pas référence à Karl Marx. Cet article s'interroge sur la trajectoire de cette référence savante à Marx au sein du SPD à partir des processus concrets d'écriture de ce célèbre programme. Il identifie une séquence dans ce travail d'écriture : entre mars 1958 (projet de programme de Stuttgart) et novembre 1959 (programme de Bad Godesberg), la référence à Marx est abandonnée. Il s'agit de décrire les mécanismes concrets de cette disparition de Marx et montre qu'elle résulte pour partie des transformations des rapports de force intrapartisans après 1945. La modification de la morphologie du personnel intellectuel « programmateur » et le déplacement concomitant des équilibres intrapartisans la rendent possible. Les « intellectuels » ne sont plus, au contraire des années 1920, les hommes d'État sociaux-démocrates dominants ; le « marxisme » n'est plus la doxa d'une classe dirigeante. La référence à Marx est portée par un groupe d'experts fortement dotés en capital intellectuel, mais marginaux dans l'espace partisan et, à ce titre, incapables de faire officialiser leur compromis programmatique dans la lutte intrapartisane. Cet article constitue donc, tout à la fois, une réflexion sur la genèse des programmes et une révision de l'historiographie faisant de Bad Godesberg une nécessité historique.
Que faire de la théorie au Parti socialiste ?
Authors: Yon Karel 
Published: March 2011

Résumé L'analyse des reconversions politiques mobilise généralement deux registres : les trajectoires biographiques et les contraintes structurales qui les encadrent. Cet article propose d'explorer une troisième piste : les formes de théorisation mobilisées par les acteurs dans le cours même de leur évolution. On s'interroge ainsi sur les modalités d'évaporation de la référence marxiste dans la trajectoire du groupe « Convergences socialistes » (CS), passé du trotskysme au Parti socialiste en 1986. Pour ce faire, la notion de carrière offre une grille de lecture originale. Plutôt que d'aborder la théorie comme un discours de justification des pratiques, elle permet de la considérer en elle-même comme une pratique. À cette aune, « le marxisme » de C.S. prend successivement trois formes. L'article décrit l'enchaînement de ces séquences, qualifiées de militante-constituante, intellectuelle-distinctive et morale-mémorielle. Souligner le caractère décisif des changements organisationnels dans les transitions d'une forme à l'autre permet de montrer que le marxisme se dissout en même temps que le groupe change de nom : initialement appelé « Convergences socialistes », il est rebaptisé « Jean-Christophe Cambadélis » au cours du chemin.
Purification of Nano‐Porous Silicon for Biomedical Applications
Authors: Koynov Svetoslav , Pereira Rui N. , Crnolatac Ivo , Kovalev Dmitry , Huygens Ann , Chirvony Vladimir , Stutzmann Martin , de Witte Peter 
Published: March 2011

AbstractRecently, various bio‐medical applications of nanoporous silicon (np‐Si) have been suggested. This work investigates the biocompatibility of np‐Si particles taking into account hazardous residua confined in the pores after preparation. The emphasis is on the potential application of such particles as oxygen photosensitizer for photodynamic therapy of cancer, which requires both negligible toxicity of np‐Si particles in darkness and a high photo‐cyto‐toxic effect due to generation of singlet oxygen under illumination. Considerable amounts of water soluble toxic impurities are found to be present in the nanoporous shell of micrometer‐sized np‐Si particles immediately after their preparation by chemical etching of bulk silicon powder. The effects of several ordinary cleaning treatments are investigated by using thermal effusion mass‐spectroscopy and FTIR spectroscopy. A particular purification procedure is developed, capable to reduce the concentration of residual impurities to levels acceptable for bio‐medical applications while preserving the required photo‐activity of the np‐Si particles.
Organic Solar Cells: Polythiophene: Perylene Diimide Solar Cells – the Impact of Alkyl‐Substitution on the Photovoltaic Performance (Adv. Energy Mater. 2/2011)
Authors: Kamm Valentin , Battagliarin Glauco , Howard Ian A. , Pisula Wojciech , Mavrinskiy Alexey , Li Chen , Müllen Klaus , Laquai Frédéric 
Published: March 2011

AbstractThe photovoltaic parameters, i.e., the short‐circuit current, open‐circuit voltage and device fill factor, of bulk heterojunction solar cells that use perylene diimide (PDI) derivatives as electron acceptors are often far below the theoretically expected values for reasons still not entirely understood. This article demonstrates that the photovoltaic characteristics of blend films of regioregular poly(3‐hexylthiophene) (rr‐P3HT) and PDI molecules are improved upon using a core‐alkylated PDI derivative instead of the often used N‐alkylated PDI molecules. A doubling of the power conversion efficiency of P3HT:PDI solar cells by using the core‐alkylated PDI derivative is observed leading to an unprecedented power conversion efficiency of 0.5% for a P3HT:PDI solar cell under AM1.5 solar illumination. Furthermore, the optical properties of the novel PDI derivative are compared to two standard exclusively N‐alkylated PDI derivatives by steady‐state and time‐resolved photoluminescence spectroscopy in solution and solid state. The experiments reveal that aggregation in the solid state determines the photophysics of all PDI derivatives. However, the emission energy and excited state lifetime of the aggregates are clearly influenced by the alkyl‐substitution pattern through its effect on the packing of the PDI molecules. X‐ray diffraction experiments before and after thermal annealing of PDI:polystyrene and PDI:P3HT blends reveal subtle differences in the packing characteristics of the different PDI derivatives and, problematically, that P3HT ordering is suppressed by all of the PDI derivatives.
Solid Oxide Fuel Cells: Microstructure of Nanoscaled La0.6Sr0.4CoO3‐δ Cathodes for Intermediate‐Temperature Solid Oxide Fuel Cells (Adv. Energy Mater. 2/2011)
Authors: Dieterle Levin , Bockstaller Pascal , Gerthsen Dagmar , Hayd Jan , Ivers‐Tiffée Ellen , Guntow Uwe 
Published: March 2011

AbstractNanocrystalline La1‐xSrxCoO3‐δ (LSC) thin films with a nominal Sr‐content of x = 0.4 were deposited on Ce0.9Gd0.1O1.95 electrolyte substrates using a low temperature sol‐gel process. The structural and chemical properties of the LSC thin films were studied after thermal treatment, which included a calcination step and a variable, extended annealing time at 700 °C or 800 °C. Transmission electron microscopy combined with selected‐area electron diffraction, energy‐dispersive X‐ray spectrometry, and scanning transmission electron microscopy tomography was applied for the investigation of grain size, porosity, microstructure, and analysis of the local chemical composition and element distribution on the nanoscale. The area specific resistance (ASR) values of the thin film LSC cathodes, which include the lowest ASR value reported so far (ASRchem = 0.023 Ωcm2 at 600 °C) can be interpreted on the basis of the structural and chemical characterization.