bluuebunny/crossref_metadata_2025_split huggingface dataset:
Magnesium – der Zukunftswerkstoff für die Automobilindustrie?
Authors: Dieringa H. , Kainer K. U. 
Published: February 2007

AbstractMagnesiumlegierungen weisen ein sehr hohes Potential für den Einsatz als metallischen Konstruktionswerkstoff für die Automobilindustrie auf, wobei der Anwendungsschwerpunkt bei Druckgussbauteilen liegt. Neben der Automobilindustrie ist die Elektroniksparte der wichtigste Abnehmer für Druckgussteile aus Magnesiumlegierungen. Raumtemperaturanwendungen wie z. B. Lenkräder und Rahmenteile im Automobil oder Handy‐ und Notebookgehäuse sind industriell gut eingeführt. Sie werden aus Magnesiumlegierungen der AZ‐ oder AM‐Familie gegossen, die mit ihren guten Raumtemperatureigenschaften und der guten Giessbarkeit die Anforderungen der Industrie seit langem befriedigen. Magnesiumlegierungen, die auch bei erhöhten Temperaturen eingesetzt werden können, stellen die derzeit größten Herausforderungen im Bereich der Legierungsentwicklung für Gussanwendungen dar. Der Einsatz im Antriebsstrang eines Automobils gilt hierbei als Benchmark. Im Bereich des Magnesiumgusses findet die Weiterentwicklung jedoch nicht nur im Bereich der Legierungsentwicklung, sondern auch auf der Verfahrensseite statt. Semi‐Solid‐Verfahren, wie das New‐Rheocasting (NRC), das Thixomolding (TM) oder das Thixocasting (TC) werden an die Erfordernisse der zu verarbeitenden Magnesiumlegierungen angepasst. Neben dem Gussbereich ist das Interesse in den letzten Jahren verstärkt auf magnesiumbasierte Knetlegierungen gefallen. Notwendig sind hier auf der einen Seite Legierungsentwicklung, um die Umformbarkeit und die Mikrostruktur zu verbessern und auf der anderen Seite Weiterentwicklungen der Pozesstechnik auf den Gebieten Strangpress‐ und Walztechnologien, um optimale Parameter für die wegen der hexagonalen Gitterstruktur der Magnesiumlegierungen schwierigen Umformbedingungen zu schaffen.
PVD‐Nanocomposite‐Beschichtungen für die Zerspanungs‐ und Umformtechnik
Authors: Reich S. , Schadewald M. , Bornemann M. 
Published: February 2007

AbstractPhysikalisch und chemisch abgeschiedene Verschleißschutzschichten weisen zunehmend komplexere Strukturen auf. Analog zur Einwicklung kompakter Materialien entstehen auch hier vermehrt Lösungen als Verbundwerkstoffe, welche in Form von Nanocomposites angeboten werden. Eine industriell verfügbare Lösung stellt das System MeN/Si3N4 dar. Dieses soll bezüglich seiner Eigenschaften sowie seiner Einsatzmöglichkeiten im Bereich der Zerspanungs‐ und Umformtechnik vorgestellt werden.
Abscheidung von Palladium und Palladiumlegierungen mit hohen Schichtdicken für die Mikrosystemtechnik
Authors: Günther E. , Jakob C. , Kutzschbach P. , Mache T. 
Published: February 2007

AbstractDie Abscheidung von Metallen und Legierungen in Mikrostrukturen erfordert meist eine Schichtdicke größer als 100 μm, die der Strukturhöhe entspricht. Für die Nutzung von Edelmetallen in Mikrosystemen ist die Abscheidung von spannungsarmen, rissfreien, porenfreien und duktilen Schichten notwendig. Da die kommerziell abgeschiedenen Edelmetallschichten nur bis etwa 10 μm qualitätsgerecht abgeschieden werden können, sind geeignete Zusätze und Variation der Abscheidungsbedingungen erforderlich, um mikrosystemtaugliche Elektrolyte zu entwickeln. Charakterisierung der Schichteigenschaften, Parameter der Abscheidungstechnologie und Anwendungsbeispiele werden aufgeführt. Erste Ergebnisse werden vorgestellt und diskutiert.
Virtuelles Werkstoff‐ und Prozessdesign funktionaler Schichten
Authors: Wilden J. 
Published: February 2007

AbstractHeute verfügbare Beschichtungsverfahren, wie das Thermische Spritzen oder auch das Plasma‐Pulver‐Auftragschweißen werden heute vorrangig zur Verbesserung der Korrosions‐ und Abrasionsbeständigkeit von Bauteilen eingesetzt. Eine Erweiterung der Anwendungsgrenzen ist möglich, wenn es gelingt, die Struktur der Schicht gezielt an das jeweilige Anforderungsprofil anzupassen. Gleichzeitig ist darauf zu achten, dass bei einer hohen Prozesseffizienz und Flexibilität des Beschichtungsprozesses eine gleich bleibend hohe Schichtgüte erzielt wird. Die Modellierung von Beschichtungsprozessen erlaubt es, Zusammenhänge zwischen den Prozessparametern und der Gefügestruktur mit einem Minimum an experimentellen Untersuchungen zu erarbeiten. Ebenso wird es möglich, die Schichtqualität und die Prozesseffizienz gezielt zu steigern und somit durch Veränderung der Prozesskenngrößen eine gezielte Beeinflussung des sich ausbildenden Gefüges zu erreichen. Am Beispiel der Modellierung thermischer Spritzprozesse, insbesondere des Lichtbogenspritzens und des Vakuumplasmaspritzens wird erläutert, welchen Einfluss Veränderungen der Prozessparameter auf die einzelnen, beim thermischen Spritzen ablaufenden Prozesse ausüben. Berücksichtigt wird die Gasströmung, das Aufheizen, Aufschmelzen und Beschleunigen des Spritzwerkstoffs. Von Bedeutung für die Gefügeausbildung ist aber auch die Ausbreitung der einzelnen Spritzpartikel auf dem Substrat, die Schichtbildung durch Überlagerung vieler Partikel und die Erstarrung. Systematische Untersuchungen belegen den Einfluss der Prozessparameter auf die Partikeleigenschaften, die Abkühlung und Erstarrung und damit auf das Gefüge.
Optimization of Dielectric Properties of Suspension Plasma Sprayed Hydroxyapatite Coatings
Authors: Jaworski R. , Pierlot C. , Tomaszek R. , Pawlowski L. , Znamirowski Z. , Zdanowski J. 
Published: February 2007

AbstractConventional plasma torch was adapted to spray very fine Ca5 (PO4)3OH (hydroxyapatite, HA) precursors having sizes ranging from a few hundreds of nanometers to a few micrometers. The powders were put in suspension with distilled water and antidispersive agent. A home made suspension feeder, including two peristaltic pumps, delivered the suspension into atomizer and therefrom injected into plasma jet. The suspension flow rate was electronically controlled. The resulting coatings had the thickness of a few tenths of μm. The electrical properties of the coatings including breakdown voltage and loss factor of suspension sprayed hydroxyapatite coatings sprayed onto aluminium substrates were also tested. The influence of such experimental factors as power input to plasma, pressure of atomizing gas, spray distance and suspension feed rate on the responses being the electrical properties was investigated using a 24 design of experiments (DOE). The mathematical models relating the responses with the factors were created and the significant factors were selected.
Maillard reaction indicators in diets usually consumed by adolescent population
Authors: Delgado‐Andrade Cristina , Seiquer Isabel , Navarro M. Pilar , Morales Francisco J. 
Published: February 2007

AbstractContents of some indicators of the Maillard reaction (MR) in two diets adjusted to the adolescent requirements are compared: the A‐diet, usually consumed by the adolescent population containing their preferred foods cooked by the culinary techniques more frequently chosen; and the B‐diet, with the same foods, except those industrially processed and with high content of Maillard reaction products (MRP), cooked in softer processes to minimise the MR. Aliquots of a lunch‐dinner (LD) and breakfast‐afternoon (BA) snack pools separately from both diets were ground and lyophilised. Fluorescence associated to MRP, CIELAB colour parameters, furosine, hydroxymethylfurfural (HMF), carboxymethyllysine (CML) and sugar contents were investigated in the samples. Significant losses of lightness were manifested in A samples compared to the B ones. Fluorescence intensity was significantly higher in the LD and BA samples from the A‐diet. Furosine measured in the A‐diet was similar to that found in the B‐diet. However, HMF content was significantly higher in the A‐diet, as well as CML. Data showed significant higher levels of advanced MRP in the usual diet. Thus, MRP intake associated to alimentary pattern in the adolescence population might be studied in order to assess the health implications of the MRP consumption and its possible synergic effect with endogenous advanced glycation endproducts.
Urinary 2‐ethyl‐3‐oxohexanoic acid as major metabolite of orally administered 2‐ethylhexanoic acid in human
Authors: Stingel Dana , Feldmeier Peter , Richling Elke , Kempf Michael , Elss Sandra , Labib Samira , Schreier Peter 
Published: February 2007

AbstractHuman metabolism of 2‐ethylhexanoic acid (2‐EHA), which is a known metabolite of important phthalates, was investigated using 2‐EHA‐contaminated food. The results of our studies reveal that the major catabolic pathway of 2‐EHA in human is β‐oxidation. The dominant final urinary metabolite was identified and quantified as 3‐oxo‐2‐ethylhexanoic acid (3‐oxo‐2‐EHA), but only after immediate methylation of the extract from urine and prior to GC‐MS analysis. Former studies without the precaution of immediate methylation had found 4‐heptanone as the major metabolite, which is obviously an artifact arising from the decarboxylation of 3‐oxo‐2‐EHA.
Optimized techniques for the extraction of grape allergens appropriate for in vivo and in vitro testing and diagnosis
Authors: Vassilopoulou Emilia V. , Zuidmeer Laurian , Akkerdaas Jaap , Rigby Neil , Moreno F. Javier , Papadopoulos Nikolaos G. , Saxoni‐Papageorgiou Photini , Mills Clare , van Ree Ronald 
Published: February 2007

AbstractStandardized allergen extracts are needed for diagnosis and therapy purposes. For grapes, standardization is hampered by low protein and high tannin and pectin concentrations. The aim of the current study was to develop an optimized method for the extraction of grape proteins and possibly extend this to other fruits. Several existing or modified extraction methods were compared by means of protein concentration determination, SDS‐PAGE, immunoblotting and radioallergosorbent test (RAST). An optimized extraction protocol was obtained in which we combined a high concentration of plant tissue, a concentrated, enriched and neutral buffer able to remove sugars and keep proteins soluble and a bivalent buffer for pectin removal. Both the quantitative (protein concentration) and qualitative parameters (SDS‐PAGE protein patterns and IgE reactivity) were compared to standard protocols and commercial extracts used as diagnostic tools in the clinical practice. This method proved to be the most efficient mainly compared to the standard Björksten protocol in extracting the low molecular weight proteins, including the major grape allergen (lipid transfer protein, Vit v 1). It proved to be an easy, low cost and reproducible method proposed to prepare grape extracts that could replace the commercially available ones, used for diagnosis and possibly extend the method to other fruits especially in extracting LTPs.
NMR spectral assignments of a new chlorotryptamine alkaloid and its analogues from Acacia confusa
Authors: Buchanan Malcolm S. , Carroll Anthony R. , Pass David , Quinn Ronald J. 
Published: February 2007

AbstractA new chlorotryptamine alkaloid, N‐chloromethyl‐N,N‐dimethyltryptamine, was isolated from a methanol extract of the Chinese shrub Acacia confusa Merr., together with its known hallucinogenic analogues, N‐methyltryptamine, N,N‐dimethyltryptamine and N,N‐dimethyltryptamine‐N‐oxide. The new compound was an artefact of the isolation conditions. The complete 1H and 13C NMR assignments for these compounds were carried out using 1H, 13C, DEPT, gCOSY, gHSQC and gHMBC NMR experiments. Copyright © 2007 John Wiley & Sons, Ltd.
SESAME‐HSQC for simultaneous measurement of NH and CH scalar and residual dipolar couplings
Authors: Würtz Peter , Permi Perttu 
Published: February 2007

AbstractWe present a novel pulse sequence, SESAME‐HSQC, for the simultaneous measurement of several NH and CH scalar and residual dipolar couplings in double labeled proteins. The proposed Spin‐statE Selective All Multiplicity Edited (SESAME)‐HSQC combines gradient selected and sensitivity enhanced 15N‐ and constant‐time 13C‐HSQC experiments with the recently introduced spin‐state selective method (Nolis et al., J. Magn. Reson. 180 (2006) 39–50) for measuring couplings simultaneously at amide and aliphatic regions. Excellent resolution and high sensitivity is warranted by removing all coupling interactions during the indirectly detected t1 period, and by employing pulsed field gradients for coherence selection and utilizing coherence order selective spin‐state selection. The scalar and residual dipolar couplings can be readily measured from a two‐dimensional 15N/13C‐HSQC spectrum without additional spectral crowding. SESAME‐HSQC can be used for epitope mapping by observing chemical shift changes in both amide and aliphatic regions. Simultaneously, potential conversion in protein conformation can be probed by analyzing changes in residual dipolar couplings induced by ligand binding. The pulse sequence is experimentally verified with a sample of 15N/13C enriched human ubiquitin. The internuclear vector directions determined from the residual dipolar couplings are found to be in excellent correlation with those predicted from ubiquitin's refined solution structure. Copyright © 2007 John Wiley & Sons, Ltd.
Comparison of 2‐D LC and 3‐D LC with post‐ and pre‐tryptic‐digestion SEC fractionation for proteome analysis of normal human liver tissue
Authors: Zhang Jie , Xu Xiuqing , Gao Mingxia , Yang Pengyuan , Zhang Xiangmin 
Published: February 2007

AbstractThe current “shotgun” proteomic analysis, strong cation exchange‐RPLC‐MS/MS system, is a widely used method for proteome research. Currently, it is not suitable for complicated protein sample analysis, like mammal tissues or cells. To increase the protein identification confidence and number, an additional separation dimension for sample fractionation is necessary to be coupled prior to current multi‐dimensional protein identification technology (MudPIT). In this work, SEC was elaborately selected and applied for sample prefractionation in consideration of its non‐bias against sample and variety of choice of mobile phases. The analysis of the global lysate of normal human liver tissue sample provided by the China Human Liver Proteome Project, were performed to compare the proteome coverage, sequence coverage (peptide per protein identification) and protein identification efficiency in MudPIT, 3‐D LC‐MS/MS identification strategy with preproteolytic and postproteolytic fractionation. It was demonstrated that 3‐D LC‐MS/MS utilizing protein level fractionation was the most effective method. A MASCOT search using the MS/MS results acquired by QSTARXL identified 1622 proteins from 3‐D LC‐MS/MS identification approaches. A primary analysis on molecular weight, pI and grand average hydrophobicity value distribution of the identified proteins in different approaches was made to further evaluate the 3‐D LC‐MS/MS analysis strategy.
Proteomic analysis of SET‐binding proteins
Authors: Vera Jorge , Estanyol Josep M. , Canela Nuria , Llorens Franc , Agell Neus , Itarte Emilio , Bachs Oriol , Jaumot Montserrat 
Published: February 2007

AbstractThe protein SET is involved in essential cell processes such as chromatin remodeling, apoptosis and cell cycle progression. It also plays a critical role in cell transformation and tumorogenesis. With the aim to study new SET functions we have developed a system to identify SET‐binding proteins by combining affinity chromatography, MS, and functional studies. We prepared SET affinity chromatography columns by coupling the protein to activated Sepharose 4B. The proteins from mouse liver lysates that bind to the SET affinity columns were resolved with 2‐DE and identified by MS using a MALDI‐TOF. This experimental approach allowed the recognition of a number of SET‐binding proteins which have been classified in functional clusters. The identification of four of these proteins (CK2, eIF2α, glycogen phosphorylase (GP), and TCP1‐β) was confirmed by Western blotting and their in vivo interactions with SET were demonstrated by immunoprecipitation. Functional experiments revealed that SET is a substrate of CK2 in vitro and that SET interacts with the active form of GP but not with its inactive form. These data confirm this proteomic approach as a useful tool for identifying new protein–protein interactions.
Design of atto‐vial based recombinant antibody arrays combined with a planar wave‐guide detection system
Authors: Ghatnekar‐Nilsson Sara , Dexlin Linda , Wingren Christer , Montelius Lars , Borrebaeck Carl A. K. 
Published: February 2007

AbstractAntibody microarray is a rapidly emerging, powerful approach with great promise within high‐throughput proteomics. However, before a truly proteome‐wide analysis can be performed, the antibody array format needs to be miniaturized even further in order to enable ultradense arrays to be fabricated. To this end, we have designed and generated proof‐of‐concept for the first generation of an atto‐vial based recombinant antibody array platform. Briefly, we have designed a novel nanostructured substrate using electron beam lithography. Vials, ranging in volume/size from 6 (200 nm in diameter) to 4000 aL (5 μm in diameter), were fabricated. Human recombinant single‐chain Fv antibody fragments, microarray adopted by design, were used as probes. The set‐up was interfaced with planar wave‐guide technology for evanescant field fluorescence detection. The results showed that protein analytes could be specifically detected in the subzeptomole range for pure systems, using vials down to 57 aL. Further, low‐abundant (pg/mL) protein analytes could be detected in directly labeled complex proteomes, such as human whole serum, using 157 aL‐vials. Taken together, these results outline the potential of the atto‐vial array set‐up for miniaturized affinity proteomics‐based approaches.
Ruthenium (II) tris‐bathophenanthroline disulfonate is well suitable for Tris‐Glycine PAGE but not for Bis‐Tris gels
Authors: Moebius Jan , Denker Katrin , Sickmann Albert 
Published: February 2007

AbstractPre‐cast bis(2‐hydroxyethyl)iminotris(hydroxymethyl)methane (Bis‐Tris) gels have proven to be very suitable for pre‐fractionation for LC‐MS/MS analysis due to high reliability and long stability. To visualize proteins within gels fluorescence dyes proved to be a good tradeoff between sensitivity and MS‐compatibility. The custom‐made ruthenium dye represents a low‐cost alternative regarding fluorescence‐based protein visualization with high sensitivity. We demonstrate, that this dye is incompatible with Bis‐Tris gels, while using Tris‐Glycine gels a competitive sensitivity to commercially available stains can be achieved.
Improved comparative proteome analysis based on two‐dimensional gel electrophoresis
Authors: Eravci Murat , Fuxius Sandra , Broedel Oliver , Weist Stephanie , Eravci Selda , Mansmann Ulrich , Schluter Hartmut , Tiemann Joachim , Baumgartner Andreas 
Published: February 2007

AbstractThe purpose of this study was to test the extent to which differences in spot intensity can be reliably recognized between two groups of two‐dimensional electrophoresis gels (pH 4–7, visualized with ruthenium fluorescent stain) each loaded with different amounts of protein from rat brain (power analysis). Initial experiments yielded only unsatisfactory results: 546 spots were matched from two groups of 6 gels each loaded with 200 µg and 250 µg protein, respectively. Only 72 spots were higher (p<0.05), while 58 spots were significantly lower in the 250‐µg group. The construction of new apparatuses that allowed the simultaneous processing of 24 gels throughout all steps between rehydration and staining procedure considerably lowered the between‐gel variation. This resulted in the detection of significant differences in spot intensities in 77–90% of all matched spots on gel groups with a 25% difference in protein load. This applied both when protein from 24 biological replicates was loaded onto two groups of 12 gels and when two pooled tissue samples were each loaded onto 6 gels. At a difference of 50% in protein load, more than 90% of all spots differed significantly between two experimental groups.
Automation of nanoflow liquid chromatography‐tandem mass spectrometry for proteome analysis by using a strong cation exchange trap column
Authors: Jiang Xiaogang , Feng Shun , Tian Ruijun , Han Guanghui , Jiang Xinning , Ye Mingliang , Zou Hanfa 
Published: February 2007

AbstractAn approach was developed to automate sample introduction for nanoflow LC‐MS/MS (μLC‐MS/MS) analysis using a strong cation exchange (SCX) trap column. The system consisted of a 100 μm id×2 cm SCX trap column and a 75 μm id×12 cm C18 RP analytical column. During the sample loading step, the flow passing through the SCX trap column was directed to waste for loading a large volume of sample at high flow rate. Then the peptides bound on the SCX trap column were eluted onto the RP analytical column by a high salt buffer followed by RP chromatographic separation of the peptides at nanoliter flow rate. It was observed that higher performance of separation could be achieved with the system using SCX trap column than with the system using C18 trap column. The high proteomic coverage using this approach was demonstrated in the analysis of tryptic digest of BSA and yeast cell lysate. In addition, this system was also applied to two‐dimensional separation of tryptic digest of human hepatocellular carcinoma cell line SMMC‐7721 for large scale proteome analysis. This system was fully automated and required minimum changes on current μLC‐MS/MS system. This system represented a promising platform for routine proteome analysis.
Infrared‐based protein detection arrays for quantitative proteomics
Authors: Loebke Christian , Sueltmann Holger , Schmidt Christian , Henjes Frauke , Wiemann Stefan , Poustka Annemarie , Korf Ulrike 
Published: February 2007

AbstractThe advancement of efficient technologies to comply with the needs of systems biology and drug discovery has so far not received adequate attention. A substantial bottleneck for the time‐resolved quantitative description of signaling networks is the limited throughput and the inadequate sensitivity of currently established methods. Here, we present an improved protein microarray‐based approach towards the sensitive detection of proteins in the fg‐range which is based on signal detection in the near‐infrared range. The high sensitivity of the assay permits the specific quantification of proteins derived from as little as only 20 000 cells with an error rate of only 5%. The capacity is limited to the analysis of up to 500 different samples per microarray. Protein abundance is determined qualitatively, and quantitatively, if recombinant protein is available. This novel approach was called IPAQ (infrared‐based protein arrays with quantitative readout). IPAQ offers a highly sensitive experimental approach superior to the established standard protein quantification technologies, and is suitable for quantitative proteomics. Employing the IPAQ approach, a detailed analysis of activated signaling networks in biopsy samples and of crosstalk between signaling modules as required in drug discovery strategies can easily be performed.