bluuebunny/crossref_metadata_2025_split huggingface dataset:
Deformation behavior, corrosion resistance, and cytotoxicity of Ni‐free Zr‐based bulk metallic glasses
Authors: Liu L. , Qiu C.L. , Chen Q. , Chan K.C. , Zhang S.M. 
Published: October 2007

AbstractTwo Ni‐free bulk metallic glasses (BMGs) of Zr60Nb5Cu22.5Pd5Al7.5 and Zr60Nb5Cu20Fe5Al10 were successfully prepared by arc‐melting and copper mold casting. The thermal stability and crystallization were studied using differential scanning calorimetry. It demonstrates that the two BMGs exhibit very good glass forming ability with a wide supercooled liquid region. A multi‐step process of crystallization with a preferential formation of quasicrystals occurred in both BMGs under continuous heating. The deformation behavior of the two BMGs was investigated using quasi‐static compression testing. It reveals that the BMGs exhibit not only superior strength but also an extended plasticity. Corrosion behaviors of the BMGs were investigated in phosphate buffered solution by electrochemical polarization. The result shows that the two BMGs exhibit excellent corrosion resistance characterized by low corrosion current densities and wide passive regions. X‐ray photoelectron spectroscopy analysis revealed that the passive film formed after anodic polarization was highly enriched in zirconium, niobium, and aluminum oxides. This is attributed to the excellent corrosion resistance. Additionally, the potential cytotoxicity of the two Ni‐free BMGs was evaluated through cell culture for 1 week followed by 3‐(4,5‐Dimethylthiazol‐2‐yl‐)‐2,5‐diphenyltetrazolium bromide assay and SEM observation. The results indicate that the two Ni‐free BMGs exhibit as good biocompatibility as Ti‐6Al‐4V alloy, and thus show a promising potential for biomedical applications. © 2007 Wiley Periodicals, Inc. J Biomed Mater Res, 2008
Convergent evolution in feeding types: Salivary gland mass differences in wild ruminant species
Authors: Hofmann Reinold R. , Streich W. Jürgen , Fickel Jörns , Hummel Jürgen , Clauss Marcus 
Published: October 2007

AbstractIn the ongoing debate about divergent evolutionary morphophysiological adaptations of grazing and browsing ruminants, the size of the salivary glands has received special attention. Here, we report the most comprehensive dataset on ruminant salivary glands so far, with data on the Glandula parotis (n = 62 species), Gl. mandibularis (n = 61), Gl. buccalis ventralis (n = 44), and Gl. sublingualis (n = 30). All four salivary gland complexes showed allometric scaling with body mass (BM); in all cases, the 95% confidence interval for the allometric exponent included 0.75 but did not include 1.0 (linearity); therefore, like other parameters linked to the process of food intake, salivary gland mass appears to be correlated to metabolic body weight (BM0.75), and comparisons of relative salivary gland mass between species should rather be made on the basis of BM0.75 than as a percentage of BM. In the subsequent analyses, the percentage of grass (%grass) in the natural diet was used to characterize the feeding type; the phylogenetic tree used for a controlled statistical evaluation was entirely based on mitochondrial DNA information. Regardless of phylogenetic control in the statistical treatment, there was, for all four gland complexes, a significant positive correlation of BM and gland mass, and a significant negative correlation between %grass in the natural diet and gland mass. If the Gl. parotis was analyzed either for cervid or for bovid species only, the negative correlation of gland mass and %grass was still significant in either case; an inspection of certain ruminant subfamilies, however, suggested that a convergent evolutionary adaptation can only be demonstrated if a sufficient variety of ruminant subfamilies are included in a dataset. The results support the concept that ruminant species that ingest more grass have smaller salivary glands, possibly indicating a reduced requirement for the production of salivary tannin‐binding proteins. J. Morphol., 2008. © 2007 Wiley‐Liss, Inc.
Developmental morphology of the neonatal alligator (Alligator mississippiensis) ovary
Authors: Moore Brandon C. , Uribe‐Aranzábal Mari Carmen , Boggs Ashley S.P. , Guillette Louis J. 
Published: October 2007

AbstractAmerican alligator (Alligator mississippiensis) ovary development is incomplete at hatching. During the months following hatching, the cortical processes of oogenesis started in ovo continues and folliculogenesis is initiated. Additionally, the medullary region of the gonad undergoes dramatic restructuring. We describe alligator ovarian histology at hatching, 1 week, 1 month, and 3 months of age in order to characterize the timing of morphological development and compare these findings to chicken ovary development. At hatching, the ovarian cortex presents a germinal epithelium containing oogonia and a few primary oocytes irregularly scattered between somatic epithelial cells. The hatchling medulla shows fragmentation indicative of the formation of lacunae. By 1 week of age, oocytes form growing nests and show increased interactions with somatic cells, indicative of the initiation of folliculogenesis. Medullary lacunae increase in diameter and contain secretory material in their lumen. At 1 month, nest sizes and lacunar diameters continue to enlarge. Pachytene oocytes surrounded by somatic cells are more frequent. Trabeculae composed of dense irregular connective tissue divide cortical nests. Three months after hatching oocytes in meiotic stages of prophase I up to diplotene are present. The ovary displays many enlarged follicles with oocytes in diplotene arrest, thecal layers, lampbrush chromosomes, and complete layers of follicular cells. The medulla is an elaborated complex of vascularized lacunae underlying the cortex and often containing discrete lymphoid aggregates. While the general morphology of the alligator ovary is similar to that of the chicken ovary, the progression of oogenesis and folliculogenesis around hatching is notably slower in alligators. Diplotene oocytes are observed at hatching in chickens, but not until 3 months in alligators. Folliculogenesis is completed at 3 weeks in chickens whereas it is still progressing at 3 months in alligators. J. Morphol., 2008. © 2007 Wiley‐Liss, Inc.
Structure elucidation of glycoproteins by direct nanoESI MS and MS/MS analysis of proteolytic glycopeptides
Authors: Henning Stefanie , Peter‐Katalinić Jasna , Pohlentz Gottfried 
Published: October 2007

AbstractBovine ribonuclease B (RNAse B) and asialofetuin (FETUA) were subjected to in‐capillary tryptic digest (Pohlentz et al. Proteomics. 2005, 5, 1758–1763) and the obtained glycopeptides were analyzed, respectively, by nanoelectrospray ionization mass spectrometry and collision‐induced dissociation (CID) during the ongoing digest. For RNAse, B glycans of the high‐mannose type (Man4 to Man9) attached to either a tetra‐ or a hexapeptide containing the sole N‐glycosylation site of the protein were detected. Glycopeptides derived from all three N‐glycosylation sites of FETUA were observed, and the corresponding CID spectra proved the respective glycans to be oligosaccharides of the triantennary complex type. Moreover, an O‐glycopeptide carrying Gal‐GalNAc at T280 could be unambiguously identified. An in‐solution tryptic/chymotryptic digest of human transferrin (TRFE) was analyzed directly for glycopeptides subsequent to the addition of methanol and formic acid. Disialylated diantennary glycans were observed in glycopeptides of both N‐glycosylation sites of TRFE. These results demonstrate the feasibility of direct structure determination of glycopeptides in proteolytic mixtures without any further refurbishment. Copyright © 2007 John Wiley & Sons, Ltd.
Kinematic analysis of kneeling in cruciate‐retaining and posterior‐stabilized total knee arthroplasties
Authors: Hamai Satoshi , Miura Hiromasa , Higaki Hidehiko , Matsuda Shuichi , Shimoto Takeshi , Sasaki Kousuke , Yoshizumi Masaaki , Okazaki Ken , Tsukamoto Nobuaki , Iwamoto Yukihide 
Published: October 2007

AbstractKneeling is an important function of the knee for many activities of daily living. In this study, we evaluated the in vivo kinematics of kneeling after total knee arthroplasty (TKA) using radiographic based image‐matching techniques. Kneeling from 90 to 120° of knee flexion produced a posterior femoral rollback after both cruciate‐retaining and posterior‐stabilized TKA. It could be assumed that the posterior cruciate ligament and the post‐cam mechanism were functioning. The posterior‐stabilized TKA design had contact regions located far posterior on the tibial insert in comparison to the cruciate‐retaining TKA. Specifically, the lateral femoral condyle in posterior‐stabilized TKA translated to the posterior edge of the tibial surface, although there was no finding of subluxation. After posterior‐stabilized TKA, the contact position of the post‐cam translated to the posterior medial corner of the post with external rotation of the femoral component. Because edge loading can induce accelerated polyethylene wear, the configuration of the post‐cam mechanism should be designed to provide a larger contact area when the femoral component rotates. © 2007 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 26:435–442, 2008
Trace elements in edible tissues of three shrimp species (Penaeus semisulcatus, Parapenaeus longirostris and Paleomon serratus)
Authors: Gokoglu Nalan , Yerlikaya Pınar , Gokoglu Mehmet 
Published: October 2007

AbstractAccumulation levels of trace elements in edible tissues of three shrimp species (Penaeus semisulcatus, Parapenaeus longirostris and Paleomon serratus) from the Gulf of Antalya, Turkey were investigated. Copper (Cu), cadmium (Cd), zinc (Zn), iron (Fe) and manganese (Mn) concentrations were determined by atomic absorption spectrophotometry. The lowest Cu (1.33 mg kg−1) and Cd (0.23 mg kg−1) and highest Mn (1.52 mg kg−1) concentrations were found in P. longirostris, the lowest Zn (6.25 mg kg−1), Fe (1.84 mg kg−1) and Mn (0.25 mg kg−1) concentrations in P. serratus and the highest Cu (6.19 mg kg−1), Cd (2.36 mg kg−1), Zn (30.84 mg kg−1) and Fe (33.89 mg kg−1) concentrations in P. semisulcatus. The Cd levels detected in P. semisulcatus and P. serratus were above legislative limits. Our results show that there were significant differences in trace element concentrations among the three shrimp species. The highest levels of the five trace elements investigated, with the exception of Mn, were found in edible tissue of P. semisulcatus. Copyright © 2007 Society of Chemical Industry
Development of an Automated Cross‐Fractionation Apparatus (TREF‐GPC) for a Full Characterization of the Bivariate Distribution of Polyolefins
Authors: Ortin Alberto , Monrabal Benjamin , Sancho‐Tello Juan 
Published: October 2007

AbstractSummary: A compact automated instrument has been developed for measuring the bivariate distribution by TREF fractionation and subsequent GPC analysis of the fractions in a single run. The configuration of this instrument and its operation principles are covered here. High resolution TREF fractionation of HDPE and fast methods with overlapped GPC injections are also discussed. Future developments, such the addition of comonomer or molar mass sensitive detectors, as well as operation in GPC – TREF mode for broad MWD resins are outlined.
Molecular Topology Fractionation of Polystyrene Stars and Long Chain Branched Polyethylene Fractions
Authors: Meunier David M. , Stokich Theodore M. , Gillespie David , Smith Patrick B. 
Published: October 2007

AbstractSummary: Control of long chain branching (LCB) architecture is an area of considerable interest in materials science because LCB can have a dominating effect on polymer rheology and properties. Currently no analytical technique provides a quantitative description of the LCB topologies in these materials beyond a basic estimation of the average number of branch points per molecule. Neither the molecular weight of the branch, nor the shape of the branched molecule (e. g. star, comb, “H” or other) can be determined using current state of the art methodology such as size exclusion chromatography (SEC) with molecular weight sensitive detectors or nuclear magnetic resonance spectroscopy.In our laboratory, we have developed a fractionation method that sorts polymer solutes based on LCB topology. The approach, which we term molecular topology fractionation (MTF), utilizes a separating medium comprising channels having dimensions similar in size to the dimensions of the macromolecules being analyzed. An applied flow field provides the driving force for the separation. Although the details of the separation mechanism are not well understood at this time, two possible mechanisms are being considered. In one, dissolved solute molecules are restricted by the channels such that the relaxation modes for reorientation determine the rate of transport. In the second, pinning (or entanglement) of molecules on the stationary phase determines the rate of transport. Both mechanisms result in the largest molecules eluting latest (opposite to the sequencing in SEC), and produce significant additional retardation for LCB chains above that of linear chains. This additional retardation leads to fractionation of an LCB distribution even if the hydrodynamic radii of the components are the same.In this paper, an overview of the MTF experiment will be provided. MTF fractionation of PS stars is presented to demonstrate the separation of LCB chains from linear chains and LCB chains based on topology. The application of MTF for characterizing LCB polyolefin fractions will be shown. The paper will also include a brief discussion of the coupling of MTF and SEC in an on line two dimensional approach for determination of LCB distributions.
Block Index for Characterizing Olefin Block Copolymers
Authors: Shan Colin Li Pi , Hazlitt Lonnie G. 
Published: October 2007

AbstractSummary: Olefin block copolymers produced by chain shuttling catalysis exhibit crystallinity characteristics that are distinct from what would be expected for typical random olefin copolymers with comparable monomer compositions produced from either ‘single‐site’ or heterogeneous catalysis. Olefin block copolymers produced by chain shuttling catalysis have a statistical multiblock architecture. A unique structural feature of olefin‐based block copolymers is that the intra‐chain distribution of comonomer is segmented (statistically non‐random). Fractionating an olefin block copolymer by preparative temperature rising elution fractionation, TREF, results in fractions that have much higher comonomer content than comparable fractions of a random copolymer collected at an equivalent TREF elution temperature. We have developed a “block index” methodology which quantifies the deviation from the expected monomer composition versus the analytical temperature rising elution fractionation, ATREF, elution temperature. When interpreted properly, this index indicates the degree to which the intra‐chain comonomer distribution is segmented or blocked. The unique crystallization behavior of block copolymers determine the magnitude of the block index values because the highly crystalline segments along an otherwise non‐crystalline chain tend to dominate the ATREF (and DSC) temperature distributions.
A Mathematical Model for the Kinetics of Crystallization in Crystaf
Authors: Anantawaraskul Siripon , Soares João B.P. , Jirachaithorn Preechathorn 
Published: October 2007

AbstractSummary: A series of ethylene homopolymers and ethylene/1‐hexene copolymers with different molecular weight distributions (MWD) and chemical composition distributions (CCD) was analyzed by crystallization analysis fractionation (Crystaf) at several cooling rates to investigate the effect of MWD, CCD, and cooling rate on their Crystaf profiles. Using these results, we developed a mathematical model for Crystaf that considers crystallization kinetic effects ignored in all previous Crystaf models and can fit our experimental profiles very well.
Thermal Stability Evaluation of PA6/LLDPE/SEBS‐g‐DEM Blends
Authors: Cataño Luis , Albano Carmen , Karam Arquímedes , Perera Rosestela , Silva Pedro 
Published: October 2007

AbstractSummary: The thermal stability of a polyamide‐6/low linear density polyethylene blend (PA6/LLDPE) was studied using thermal analysis techniques. The thermogravimetric studies carried out showed that when a diethyl maleate grafted styrene‐ ethylene/butadiene‐styrene terpolymer (SEBS‐g‐DEM) is added to the PA6/LLDPE blend there is an actual enhancement of the thermal stability due to the increase in the interfacial area within the blend. The Invariant Kinetic Parameter method (IKP) proved to be a qualitative technique unfolding the type of degradation mechanisms taking place in the material vicinity. Nucleation and phase boundary reactions are the kinetic models of thermal decomposition with the most significant probability of occurring.
Zwei Fliegen mit einer Klappe – Platencin, ein neues Antibiotikum
Authors: Holzgrabe Ulrike 
Published: October 2007

AbstractKürzlich berichtete eine Gruppe der Merck Research Laboratories über das neue Antibiotikum Platensimycin, einer Substanz, die den Fettsäureaufbau inhibieren kann und damit mit dem Aufbau von Zellmembranen und Oberflächen von Bakterien interferiert (siehe auch Treffpunkt Forschung, PharmuZ 5/06). Jetzt wurde eine ähnliche Substanz vorgestellt.
Solar cells utilizing small molecular weight organic semiconductors
Authors: Rand Barry P. , Genoe Jan , Heremans Paul , Poortmans Jef 
Published: October 2007

AbstractIn this review, we focus on the field of organic photovoltaic cells based on small molecular weight materials. In particular, we discuss the physical processes that lead to photocurrent generation in organic solar cells, as well as the various architectures employed to optimize device performance. These include the donor–acceptor heterojunction for efficient exciton dissociation, the exciton blocking layer, the mixed or bulk heterojunction, and the stacked or tandem cell. We show how the choice of materials with known energy levels and absorption spectra affect device performance, particularly the open‐circuit voltage and short‐circuit current density. We also discuss the typical materials and growth techniques used to fabricate devices, as well as the issue of device stability, all of which are critical for the commercialization of low‐cost and high‐performance organic solar cells. Copyright © 2007 John Wiley & Sons, Ltd.
Analysis of management actions, human behavior, and process reliability in chemical plants. II. Near‐miss management system selection
Authors: Meel Anjana , Seider Warren D. , Oktem Ulku 
Published: October 2007

AbstractTo understand the behavior patterns of managers, engineers, and operators, in Part II, a game‐theoretic decision model is developed for a specific plant to balance the advantages and disadvantages of having a Near‐miss Management System (NMMS) with different sophistication levels. Assuming that management and engineering preferences differ from those of the process operators, the tradeoffs between them are balanced. As anticipated, it is shown that the choices of the management and engineering team, and the operators, for the selection of a NMMS, are sensitive to the contributing factors. This article introduces a theoretical approach, illustrated using hypothetical data, which should be effective in industrial operations. Attempts to obtain data for validation of the framework were unsuccessful because of confidentiality and liability issues associated with industrial data. © 2007 American Institute of Chemical Engineers Process Saf Prog, 2008
Novel post‐process for the passivation of a CMOS biosensor
Authors: Schindler M. , Kim S. K. , Hwang C. S. , Schindler C. , Offenhäusser A. , Ingebrandt S. 
Published: October 2007

AbstractSensors, which are designed and fabricated in complementary metal oxide semiconductor (CMOS) technology, have become increasingly important in the field of bioelectronics. The standardized industry processes enable a fast, cheap, and reliable fabrication of biosensor devices with integrated addressing and processing units. However, the interfacing of such chips with a liquid environment has been a challenge in recent years. Especially for interfacing living cells with CMOS biosensors different elaborate post‐processes have been proposed. In this article we describe a novel and single step passivation of a CMOS biosensor using a bio‐compatible high‐permittivity thin film, which can be directly applied to the top aluminium layer of a CMOS process. The aluminium oxide and hafnium oxide multi‐layer thin films were prepared using atomic layer deposition at low process temperatures. Electrical I –V and capacitance measurements as well as electrochemical leakage current measurements were performed on films grown on aluminium bottom electrodes. The films showed a very low leakage current and were stable up to 6 V at a thickness of just 50 nm. (© 2008 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Scan registration for autonomous mining vehicles using 3D‐NDT
Authors: Magnusson Martin , Lilienthal Achim , Duckett Tom 
Published: October 2007

AbstractScan registration is an essential subtask when building maps based on range finder data from mobile robots. The problem is to deduce how the robot has moved between consecutive scans, based on the shape of overlapping portions of the scans. This paper presents a new algorithm for registration of 3D data. The algorithm is a generalization and improvement of the normal distributions transform (NDT) for 2D data developed by Biber and Strasser, which allows for accurate registration using a memory‐efficient representation of the scan surface. A detailed quantitative and qualitative comparison of the new algorithm with the 3D version of the popular ICP (iterative closest point) algorithm is presented. Results with actual mine data, some of which were collected with a new prototype 3D laser scanner, show that the presented algorithm is faster and slightly more reliable than the standard ICP algorithm for 3D registration, while using a more memory‐efficient scan surface representation. © 2007 Wiley Periodicals, Inc.
Autonomous system for navigation and surveying in underground mines
Authors: Bakambu Joseph Nsasi , Polotski Vladimir 
Published: October 2007

AbstractThis paper describes an autonomous platform for navigation and surveying within networks of tunnels, as those typically found in underground mines and caves. In this context, we propose a system allowing two modes of operation: surveying and autonomous navigation mode. In the surveying mode, a remotely located supervisor instructs the platform to move through successive sections of the network, gathering range data that is then concatenated into two‐ and three‐dimensional survey maps of the environment. In navigation mode, the supervisor specifies high‐level missions using the previously acquired survey maps. A motion planner then translates each mission into a set of consecutive navigation actions separated by natural landmarks. Mission execution consists of autonomously detecting landmarks, self‐localizing, and performing the planned navigation actions. Advanced and innovative features, mostly related to surveying capabilities, navigation mode switcher, and the integrated aspect of our system, distinguish it from navigation systems used in productive mining vehicles described in the literature. The proposed system starts sharing some functionality with robotics systems devoted to exploration of abandoned mines. The full functionality of the navigation/surveying system has been proven through a series of on‐site experiments in underground mines. © 2007 Wiley Periodicals, Inc.