bluuebunny/crossref_metadata_2025_split huggingface dataset:
Bemessung von Stützmauern aus Stahlbeton nach Eurocode
Authors: Suda Jürgen , Hofmann Robert 
Published: March 2009

AbstractDie Bemessung von Stützbauwerken aus Beton und Stahlbeton erfolgt auf Basis von gültigen Betonbau und Geotechnik Normen. In Österreich wird derzeit vom nationalen Normenkonzept auf die europäischen Normenwerke (EUROCODES) umgestellt. Im folgenden Artikel wird der aktuelle Stand der Normung in Österreich und das Zusammenspiel des Eurocode 2 (EN 1992‐x) und des Eurocode 7 (EN 1997‐1) bei der Bemessung von Gewichtsmauern aus Beton und Stahlbeton gezeigt. Dabei werden die notwendigen Nachweise erläutert und deren normative Verankerungen dargestellt.
Normen für den Konstruktiven Ingenieurbau
Authors: Sigrist Viktor 
Published: March 2009

AbstractFür den Konstruktiven Ingenieurbau sind Normen unverzichtbare Grundlagen. Normen sollen die anerkannten Regeln sowie den Stand von Wissenschaft und Technik darstellen, und sie dienen der Verständigung zwischen den beteiligten Fachleuten. In den zukünftigen Normen sind alle Prozessschritte der Planung – Projektierung, Ausführung, Nutzung, Erhaltung und Rückbau – durch die integrale Betrachtung aller die Sicherheit und Qualität betreffenden Aspekte zu behandeln. Gegenüber heutigen Normen werden folglich die thematische Breite und der Detaillierungsgrad zunehmen. Das Ziel der Verfasser von Normen muss es aber gleichwohl sein, die benötigte Information mithilfe einfach handhabbarer Regeln verständlich darzustellen. Es muss gelingen, den Normen der Zukunft (wieder) die ihnen angemessene Bedeutung und hohe Akzeptanz zu verschaffen.
Macrophage migration inhibitory factor (MIF), enzymatic activity and the inflammatory response
Authors: Cooke Gordon , Armstrong Michelle E. , Donnelly Seamas C. 
Published: March 2009

AbstractMacrophage migration inhibitory factor represents a key cytokine in human diseases. It plays an important role in both innate and acquired immunity and has been shown to be a key mediator of inflammatory diseases. More recently MIF has been implicated in cancer pathogenesis. Over the decades its structure and functions have been elucidated and this has led to it being further classified as a hormone and an enzyme. It has isomerase enzymatic activity and increasing evidence implicates this activity in inflammatory disease. Consequently, there is increasing interest in developing small molecular weight inhibitors which could target this novel enzymatic activity in disease. © 2009 International Union of Biochemistry and Molecular Biology, Inc.
C/EBPα in leukemogenesis: Identity and origin of the leukemia‐initiating cell
Authors: Schuster Mikkel Bruhn , Porse Bo Torben 
Published: March 2009

AbstractThe role of the transcription factor CCATT/enhancer binding protein alpha (C/EBPα) as a lineage instructive determinant in myelopoiesis is widely accepted. Furthermore, early mutational events ultimately leading to acute myeloid leukemia (AML) often involve abrogation of C/EBPα expression and/or function. The main focus of this review is the progression from a preclinical state to AML, and which preleukemic cell population(s) might—in general and in particular in patients with CEBPA mutations—be a target for the secondary genetic and epigenetic events leading to this progression. © 2009 International Union of Biochemistry and Molecular Biology, Inc.
Direction discovery
Authors: Sikes Suzanne S. , Schwartz‐Bloom Rochelle D. 
Published: March 2009

AbstractLaunch into education about pharmacology (LEAP) is an inquiry‐based science enrichment program designed to enhance competence in biology and chemistry and foster interest in science careers especially among under‐represented minorities. The study of how drugs work, how they enter cells, alter body chemistry, and exit the body engages students to conceptualize fundamental precepts in biology, chemistry, and math. Students complete an intensive three‐week course in the fundamentals of pharmacology during the summer followed by a mentored research component during the school year. Following a 5E learning paradigm, the summer course captures student interest by introducing controversial topics in pharmacology and provides a framework that guides them to explore topics in greater detail. The 5E learning cycle is recapitulated as students extend their knowledge to design and to test an original research question in pharmacology. LEAP students demonstrated significant gains in biology and chemistry knowledge and interests in pursuing science. Several students earned honors for the presentation of their research in regional and state science fairs. Success of the LEAP model in its initial 2 years argues that coupling college‐level coursework of interest to teens with an authentic research experience enhances high school student success in and enthusiasm for science.
PCR‐RFLP to detect codon 248 mutation in exon 7 of p53 tumor suppressor gene
Authors: Ouyang Liming , Ge Chongtao , Wu Haizhen , Li Suxia , Zhang Huizhan 
Published: March 2009

AbstractIndividual genome DNA was extracted fast from oral swab and followed up with PCR specific for codon 248 of p53 tumor suppressor gene. MspI restriction mapping showed the G‐C mutation in codon 248, which closely relates to cancer susceptibility. Students learn the concepts, detection techniques, and research significance of point mutations or single nucleotide polymorphisms in individual genomes.
High school and university students' knowledge and attitudes regarding biotechnology
Authors: Usak Muhammet , Erdogan Mehmet , Prokop Pavol , Ozel Murat 
Published: March 2009

AbstractBiotechnology has a considerable importance in Turkish biology curriculum. This study was designed to explore or indicate Turkish high school and university students' knowledge and attitudes toward biotechnology. A total number of 352 high school and 276 university students were invited to the study. The Biotechnology Knowledge Questionnaire (BKQ) with 16 items and Biotechnology Attitude Questionnaire (BAQ) with 37 items were used as data collection instruments. The statistically significant correlation was observed between the level of biotechnology knowledge and the subdimensions of attitudes toward biotechnology. We found no statistically significant difference between high school and university students' knowledge of biotechnology. In contrast, university students showed more positive attitudes toward biotechnology than did high school students. However, the effect of gender was equivocal; therefore, it did not support a “gender paradox” hypothesis. Our results suggest that although students' appreciation of (agricultural) biotechnology is relatively positive, the understanding of biotechnology processes is superficial and attitudes toward shopping genetically modified products are therefore negative. The possible impact of current science and biology curriculum, and also biotechnology news given in media on Turkish students' views of biotechnology is discussed.
Pretreatment of hybrid poplar by aqueous ammonia
Authors: Gupta Rajesh , Lee Y. Y. 
Published: March 2009

AbstractEnzymatic hydrolysis of hybrid poplar treated by ammonia recycle percolation (ARP) was studied applying cellulase enzyme supplemented with additional xylanase or pectinase. The effect of xylanase addition was much more significant than pectinase addition. Conversion of ARP‐treated hybrid poplar to ethanol was carried out by simultaneous saccharification and fermentation (SSF) and SS and cofermentation (SSCF). The maximum ethanol yield observed from the SSCF experiment was 78% of theoretical maximum based on the total carbohydrate (glucan + xylan). The same feedstock was also treated by soaking in aqueous ammonia (SAA), a batch pretreatment process with lower severity than ARP. The test results indicated that relatively high severity is required to attain acceptable level of digestibility of hybrid poplar. In order to lower the severity of the pretreatment, addition of H2O2 was attempted in the SAA. Addition of H2O2 significantly enhanced delignification of hybrid poplar due to its oxidative degradation of lignin. Several different H2O2 feeding schemes and different temperature profiles were attempted in operation of the SAA to investigate the effects of H2O2 on degradation of lignin and carbohydrates in hybrid poplar. More than 60% of lignin in hybrid poplar was removed with stepwise‐increase of temperature (60–120°C after 4h of reaction). Increase of carbohydrate degradation was also observed under this condition. © 2009 American Institute of Chemical Engineers Biotechnol. Prog., 2009
Reversible Breaking and Forming of Metal–Ligand Coordination Bonds: Temperature‐Triggered Single‐Crystal to Single‐Crystal Transformation in a Metal–Organic Framework
Authors: Bernini María C. , Gándara Felipe , Iglesias Marta , Snejko Natalia , Gutiérrez‐Puebla Enrique , Brusau Elena V. , Narda Griselda E. , Monge M. Ángeles 
Published: March 2009

AbstractThe novel Yb succinate metal–organic frameworkexhibits a reversible single‐crystal to single‐crystal polymorphic transformation (see figure) when it is heated above 130 °C, returning to its initial form when back at room temperature. This transformation produces a change in the coordination sphere of the Yb atoms, which influences the catalytic activity of the material.magnified image[Yb(C4H4O4)1.5] undergoes a temperature‐triggered single‐crystal to single‐crystal transformation. Thermal X‐ray single‐crystal studies showed a reversibly orchestrated rearrangement of the atoms generated by the breaking/formation of coordination bonds, in which the stoichiometry of the compound remains unchanged. The transformation occurs on heating the crystal at ≈130 °C. This uncommon behavior was also studied by thermal methods, FTIR spectroscopy, and thermodiffractometry. Both polymorphs,α(room‐temperature form) andβ(high‐temperature form), are proven to be active heterogeneous catalysts; the higher catalytic activity ofβis owed to a decrease in the Yb coordination number. A mechanism based on spectroscopic evidence and involving formation of the active species YbOOH is proposed for the sulfide oxidation.
Semiconducting Neutral Microstructures Fabricated by Coordinative Self‐Assembly of Intramolecular Charge‐Transfer Tetrathiafulvalene Derivatives
Authors: Geng Yan , Wang Xiao‐Jun , Chen Bin , Xue Hai , Zhao Yao‐Peng , Lee Shuittong , Tung Chen‐Ho , Wu Li‐Zhu 
Published: March 2009

AbstractA new class of tetrathiafulvalene‐based microstructures fabricated by coordinative self‐assembly has been prepared by a solution process. Upon incorporation of Pb2+ and Zn2+ ions, 1D wirelike microstructures and spherical polymer particles were achieved, respectively (see picture). The neutral coordination polymers are conductive and magnetic at room temperature without external manipulation.magnified imageA new class of tetrathiafulvalene(TTF)‐based microstructures fabricated by coordinative self‐assembly has been successfully prepared by a solution process. The morphology of the TTF coordination polymers is readily tuned by the variation of metal ions. Upon incorporation of Pb2+ and Zn2+ ions, one‐dimensional (1D) wirelike microstructures and spherical polymer particles were achieved, respectively. These results indicate that the coordinative approach pursued in this work, in which the building blocks of 1 are linked in a coordination polymer chain by association with metal ions, is an efficient and versatile approach to produce more mechanically robust micro‐ and nanometer‐sized coordination polymer materials. More interestingly, the neutral coordination polymers are conductive and magnetic at room temperature without external manipulation. Such conductivity is reminiscent of the behavior of the neutral conductive TTF in single crystals.
Synthesis of 2‐Ene‐1,4‐diols by a New Cascade‐Opening of 1,3‐Diepoxides: Towards an Efficient Synthesis of Dihydroxytaxoid Derivatives
Authors: Aldegunde María J. , Castedo Luis , Granja Juan R. 
Published: March 2009

AbstractTaxing taxanes: A new method for the preparation of alk‐2‐ene‐1,4‐diols from 1,3‐dienes, especially for geometrical constrained derivatives, via dioxirane derivative formation followed by TiIII‐induced oxirane ring opening, is described. The strategy has been very efficiently implemented to the construction of the 11‐ene‐10,13‐diol moiety present in taxol derivatives.magnified image
Pivotal Role of Fluorine in Tuning Band Structure and Visible‐Light Photocatalytic Activity of Nitrogen‐Doped TiO2
Authors: Wang Qi , Chen Chuncheng , Ma Wanhong , Zhu Huaiyong , Zhao Jincai 
Published: March 2009

AbstractSynergistic interactions between N and F can be used to tune the band structures of N‐doped TiO2 (see scheme). Reduction potential of conduction band electron is positively shifted to weaken unwanted O2 reduction, but enhances the target reduction reaction in air. The tuning also enhances the oxidation ability of the valence band to oxidize water to O2, which makes photocatalytic reduction proceed without any organic sacrificial reagents.magnified image
Sequestration of Heavy Metals from Water with Layered Metal Sulfides
Authors: Manos Manolis J. , Kanatzidis Mercouri G. 
Published: March 2009

AbstractExtraordinarily effective heavy metal ion scavenger: We show here that the material K2xMnxSn3−xS6 (x=0.5–0.95) (KMS‐1) overcomes the limitations of the known heavy metal ion sorbents, showing the capability to rapidly reduce the concentrations of Cd, Hg, and Pb ions well‐below the legally acceptable levels for drinking water. KMS‐1 is inexpensive, easily prepared in large quantities, and may play a role in addressing the global problem of water contamination with heavy metal ions. The paradigm of heavy metal ion absorption of KMS‐1 is the ability to form very strong MS bonds.magnified image
Discovery of Iminosugar Derivatives with Strong IFN‐γ Inducing Activity
Authors: Zhang Lei , Sun Fang , Wang Qilong , Zhou Jing , Zhang Li‐He , Zhang Xiao‐Lian , Ye Xin‐Shan 
Published: March 2009

AbstractThrough construction of an iminosugar library and in situ cell‐based screening, several iminosugar compounds with the ability to stimulate IFN‐γ secretion in vitro were discovered. Among these compounds, one was able to strongly induce IFN‐γ secretion and showed remarkable antibacterial effects in vivo.magnified imageThrough effective construction of a compound library and in situ cell‐based screening, several iminosugar derivatives were discovered that show a strong ability to enhance IFN‐γ secretion. In particular, compounds A45 and B8, which exhibit remarkable activity in stimulating IFN‐γ secretion, show good antibacterial activity in vivo and have the potential to be lead compounds for further studies in the search for drugs for the treatment of cancer and microbial infections.
Treating octogenarian and nonagenarian acute myeloid leukemia patients—Predictive prognostic models
Authors: Harb Antoine J. , Tan Wei , Wilding Gregory E. , Ford LaurieAnn , Sait Sheila N. J. , Block AnneMarie W. , Barcos Maurice , Wallace Paul K. , Wang Eunice S. , Wetzler Meir 
Published: March 2009

AbstractBACKGROUND:Treating the octogenarian and nonagenarian patients who have acute myeloid leukemia (AML) with intensive chemotherapy is controversial. Several models to predict outcome were proposed, including the use of a comorbidity index. However, it is unclear whether the Charlson comorbidity index (CCI) or the hematopoietic cell transplant comorbidity index (HCTCI) is more sensitive.METHODS:The authors analyzed their experience with 92 patients aged ≥80 years who had AML. Patients' pretreatment characteristics and their treatment outcomes were recorded.RESULTS:All patients were offered intensive treatment; 59 patients (64%) were treated intensively with a variety of regimens, whereas 33 patients (36%) elected to receive supportive care. The CCI and the HCTCI had similar predictive ability for outcome in both groups. A multivariate analyses of prognostic factors identified near‐normal albumin (48% of patients; 1‐year survival rate, >27%) as a favorable factor for the whole cohort, age <83 years (47% of patients; 1‐year survival rate, >25%) and nonmonocytic morphology (75% of patients; 1‐year survival rate, >26%) as favorable factors for the intensively treated cohort, and bone marrow blasts <46% (50% of patients; 1‐year survival rate, >19%) as a favorable factor for patients who received supportive care.CONCLUSIONS:This retrospective analysis was developed to assist in treatment decisions for octogenarian and nonagenarian patients with AML. The findings will need validation in a prospective study. Cancer 2009. © 2009 American Cancer Society.
Transient and transgenic analysis of the zebrafish ventricular myosin heavy chain (vmhc) promoter: An inhibitory mechanism of ventricle‐specific gene expression
Authors: Zhang Ruilin , Xu Xiaolei 
Published: March 2009

AbstractThe zebrafish ventricular myosin heavy chain (vmhc) gene exhibits restricted expression in the ventricle. However, the molecular mechanism underlying this chamber‐specific expression is unclear. Here, we exploited both transient and transgenic technologies to dissect the zebrafish vmhc promoter. We demonstrated that a combination of two transient assays in this animal model quickly identified chamber‐specific cis‐elements, isolating a 2.2 kb fragment upstream from the vmhc gene that can drive ventricle‐specific expression. Furthermore, deletion analysis identified multiple cis‐elements that exhibited cardiac‐specific expression. To achieve chamber specificity, a distal element was required to coordinate with and suppress a proximal enhancer element. Finally, we discovered that Nkx2.5‐binding sites (NKE) were essential for this repressive function. In summary, our study of the zebrafish vmhc promoter suggests that ventricle‐specific expression is achieved through an inhibitory mechanism that suppresses expression in the atrium. Developmental Dynamics 238:1564–1573, 2009. © 2009 Wiley‐Liss, Inc.
Quantitative Studies of Metal Ion Adsorption on a Chemically Modified Carbon Surface: Adsorption of Cd(II) and Hg(II) on Glutathione Modified Carbon
Authors: Abiman Poobalasingam , Wildgoose Gregory G. , Crossley Alison , Compton Richard G. 
Published: March 2009

AbstractThe adsorption behavior of model toxic metal cations namely Cd(II) and Hg(II) on carbon surfaces chemically modified by glutathione was investigated as a function of the concentration of Cd2+ and Hg2+ ions, time and the amount of modified carbon used. Square wave and linear sweep anodic stripping voltammetry was used to monitor the uptake of Cd(II) and Hg(II) ions respectively. Kinetic and adsorption isotherm studies reveal that both Cd(II) and Hg(II) ions undergo similar large adsorption with the modified glutathione carbon material (Glu‐carbon).
Characterization of Kaolin Glassy Carbon Modified Electrodes: Preconcentration of 2‐Chlorophenol
Authors: Gómez Yoleydis , Fernández Lenys , Borrás Carlos , Mostany Jorge , Scharifker Benjamín 
Published: March 2009

AbstractIn this paper we describe the use of two kaolin‐type aluminosilicate clays, a commercial ceramic‐grade kaolin (K) and a natural kaolin from mines in Bolívar State Venezuela (K‐Ve), for the preparation of film‐based clay‐modified glassy carbon electrodes. We examine their behavior during the preconcentration and subsequent anodic oxidation of 2‐chlorophenol. Kaolin samples were used as raw materials and modified with cationic surfactant, cetyltrimethylammonium bromide (CTAB) or nonionic surfactant, octylphenoxypolyethoxyethanol (TX100). The electrode polishing was the key step to produce stable films. 2‐Chlorophenol electrooxidation is favored by the presence of the surfactants in the film. The X‐ray patterns show that the kaolin K‐Ve includes quartz as nonclay mineral, while the kaolin K showed only diffraction peaks characteristic of kaolinite phase. This may be why the TX100/K‐Ve/GC electrode adsorbs more 2‐CPh than the TX100/K/GC electrode. On the other hand, analysis of the limiting currents obtained from hydrodynamic techniques indicated that the permeability of TX100/kaolin films is greater than that of CTAB/kaolin films. The TX100/K‐Ve/GC electrode showed excellent stability. A linear response range from 0.01mgL−1 up to 0.1 mg L−1 with a detection limit of 0.0016 mg L−1 was observed in the optimized conditions.
A conditional expectation approach for associating ambient air pollutant exposures with health outcomes
Authors: Wannemuehler Kathleen A. , Lyles Robert H. , Waller Lance A. , Hoekstra Robert M. , Klein Mitchel , Tolbert Paige 
Published: March 2009

AbstractOur research focuses on the association between exposure to an airborne pollutant and counts of emergency department (ED) visits attributed to a specific chronic illness. The motivating example for this analysis of measurement error in time series studies of air pollution and acute health outcomes was a study of ED visits from a 20‐county Atlanta metropolitan statistical area from 1993 to 1999. The research presented illustrates the impact of using various surrogates for unobserved measurements of ambient concentrations at the zip code level. Simulation results indicate that the impact of measurement error on the association between pollutant exposure and a health outcome can be substantial. The proposed conditional expectation (CE) approach provided reliable estimates of the association and exhibited good confidence interval coverage for a variety of magnitudes of association. Use of a single‐centrally located monitor, the arithmetic average, the nearest‐neighbor monitor, and the inverse‐distance weighted average surrogates resulted in biased estimates and poor coverage rates, especially for larger magnitudes of the association. A focus on obtaining reasonable exposure measurements within clearly defined subregions is important when the pollutant exposure of interest exhibits strong spatial variability. Copyright © 2009 John Wiley & Sons, Ltd.
Early response as predictor of final remission in elderly depressed patients
Authors: Kok Rob M. , van Baarsen Carlijn , Nolen Willem A. , Heeren Thea J. 
Published: March 2009

AbstractBackgroundSeveral studies have attempted to predict the final response or remission based on improvement during the early course of treatment of major depression. There is however a great variation in cut offs used to define early response and in the optimal week to predict final results.ObjectiveTo compare different cut offs at different time points early in the treatment of elderly depressed patients.MethodA 12 week randomised, controlled trial in 81 elderly inpatients with DSM–IV major depression comparing venlafaxine with nortriptyline. At least 20, 25, 30 or 50% improvement was analysed after 1, 3 and 5 weeks using the Hamilton Depression Rating Scale and the Montgomery Asberg Depression Rating Scale. We plotted sensitivity against 1—specificity and calculated areas under the curve (AUCs).ResultsThe highest percentage of correctly classified patients is found using at least 50% decrease as cut off in week 5, with acceptable sensitivity (81.8%) and specificity (87.4%). In week 5, the AUCs were 0.891 (95% CI 0.798–0.984) and 0.866 (95% CI 0.789–0.983) for the HAM‐D and MADRS, respectively.ConclusionsCombining the results from our study and the other studies addressing this issue, we suggest that the treatment should be changed in the elderly if after 3–4 weeks less than 30% improvement in depression score has been achieved. Copyright © 2009 John Wiley & Sons, Ltd.