bluuebunny/crossref_metadata_2025_split huggingface dataset:
Medical device regulation for manufacturers
Authors: McAllister P , Jeswiet J 
Published: February 2004

Manufacturers of medical devices are held to a higher standard than manufacturers of many other products due to the potential severity of the consequences of introducing inferior or unsafe products to the market-place. In Canada, the medical device industry is regulated by Health Canada under the Medical Device Regulations of the Food and Drug Act. The Medical Device Regulations define requirements of medical device design, development and manufacture to ensure that products reaching the public are safe and effective. Health Canada also requires that medical device manufacturers maintain distribution records to ensure that devices can be traced to the source and consumers can be contacted successfully in the event that a device is recalled. Medical devices exported from Canada must be compliant with the regulations of the country of import. The Canadian Medical Device Regulations were based on the Medical Device Directives of the European Union thus facilitating approval of Canadian devices for the European market. The United States Food and Drug Administration has separate and distinct requirements for safety and quality of medical devices. While effort has been made to facilitate approval and trade of Canadian medical devices in the United States and the European Union, obtaining approval from multiple regulatory bodies can result in increased device development time and cost. The Global Harmonization Task Force is an organization composed of members from Japanese, Australian, European, Canadian and American medical device regulatory bodies. This organization was formed with the objective of harmonizing medical device regulations in an effort to facilitate international trade and standardize the quality of medical devices available to all countries. This paper discusses the requirements that must be met by manufacturers when designing and manufacturing medical devices.
On the Coherence between Dynamics of the World Fuel Consumption and Global Temperature Anomaly
Authors: Klyashtorin L.B. , Lyubushin A.A. 
Published: February 2004

Analysis of the long-term dynamics of World Fuel Consumption (WFC) and the Global Temperature anomaly (dT) for the last 140 years (1961–2000) shows that unlike the monotonously and exponentially increasing WFC, the dynamics of global dT against the background of a linear, age-long trend, undergo quasi-cyclic fluctuations with about 60 a year period. No true linear correlation has taken place between the dT and WFC dynamics in the last century. Spectral analysis of reconstructed temperature for the last 1420 years and instrumentally measured for the last 140 years global dT shows that dominant period for its variations for the last 1000 years lies in the 5060 years interval. Modelling of roughly 60–years cyclic dT changes suggest that the observed rise of dT will flatten in the next 5–10 years, and that we might expect a lowering of dT by nearly 1–0.15°C to the end of the 2020s.
Single Spine Ca2+Signals Evoked by Coincident EPSPs and Backpropagating Action Potentials in Spiny Stellate Cells of Layer 4 in the Juvenile Rat Somatosensory Barrel Cortex
Authors: Nevian Thomas , Sakmann Bert 
Published: February 2004

The precise timing of presynaptic and postsynaptic activity results in synaptic modifications, which depend on calcium influx. [Ca2+] transients in the spines of spiny neurons in layer 4 (L4) of the somatosensory barrel cortex of young rats were investigated in thalamocortical brain slices by two-photon excitation microscopy to determine the spike timing dependence of the Ca2+signal during near-coincident presynaptic and postsynaptic activity. [Ca2+] transients evoked by backpropagating action potentials (bAPs) were mediated by voltage-dependent Ca2+channels and were of comparable size in a spine and adjacent dendritic shaft. They decreased with the distance of the spine from the soma. EPSP-evoked [Ca2+] transients were restricted to spine heads and were mediated almost entirely by Ca2+influx through NMDA receptors (NMDARs). Their amplitude was independent of the position of the spine along the dendritic arbor. bAPs interacted with EPSPs to generate sublinear or supralinear Ca2+signals in a spine when EPSP and bAP occurred within a time window of ∼50 msec. Synaptic stimulation, coincident with a bAP, evoked a large postsynaptic Ca2+influx that was restricted to a single spine, even after EPSPs were blocked by the AMPA receptor antagonist NBQX that rendered synapses effectively “electrically silent.”We conclude that the spines of L4 cells can act as sharply tuned detectors for patterns of APs occurring in the boutons of the afferents to L4 cells and the spines of L4 cell dendrites. The readout for near-coincident presynaptic and postsynaptic APs is a large transient Ca2+influx into synaptically active spines mediated by the brief unblocking of NMDARs during the dendritic bAP.
Quo Vadis Bioinformatik, neue Konzepte und Arbeitsbereiche (Quo Vadis Bioinformatics – New Concepts and Areas)
Authors: Karas Holger , Tysiak Michael , Wingender Edgar 
Published: February 2004

Zusammenfassung
Bioinformatik war einer der ganz großen Trends der letzten Jahre und ist in veränderter Form immer noch ein wichtiger Bereich. Allerdings haben sich die Anforderungen gewandelt, waren früher "self-made" Informatiker für die meisten Bereiche ausreichend, so ist der Anspruch an den Bioinformatiker deutlich gestiegen aber auch klarer formuliert, was in der Vergangenheit nicht immer der Fall war.
Online Fehler-Erkennung und schnelle Wiederherstellungs-Techniken für zuverlässige eingebettete Prozessoren (Online Error Detection and Fast Recover Techniques for Dependable Embedded Processors)
Authors: Pflanz Matthias 
Published: February 2004

Zusammenfassung
Die Dissertation präsentiert neue Verfahren zur online Observierung und parallelem Check von Prozessoren durch Verfeinerung und Verbesserung bekannter Techniken und Methoden sowie Einführung neuer Ideen. Motivation war die Entwicklung von Techniken zur Fehlererkennung im selben Maschinenzyklus. Des Weiteren werden Verfahren zur schnellen Fehlerkompensation vorgestellt. Ziel ist die Erhöhung der Zuverlässigkeit von Prozessoren speziell für sicherheitskritische Systeme.
Structures, Energies and Electronic Properties of Interaction of Hydrogen Halides with Pentamer Water Cluster
Authors: Nirmala V. , Kolandaivel P. 
Published: February 2004

Abstract
Molecular orbital and density functional theory calculations have been performed to study the interaction of hydrogen halides with hydrogen bonded cluster of water pentamer, i.e. HX·(H2O)5 (where X = F, Cl, Br). Second order Møller–Plesset perturbation theory of ab initio method, B3LYP level of theory of DFT method, implementing 6-311++G** basis set have been used for the calculations. The strength of hydrogen bonds have been studied using the interaction energies of the water molecules, which were calculated after eliminating the basis set superposition error (BSSE) by Boys Counterpoise (CP) correction method and the stability of this cluster with hydrogen halides has been studied using the dipole moments, charge transfer and the topological properties. The chemical hardness and chemical potential have been calculated for the above cluster with hydrogen halides and tested the principle of maximum hardness.
Genetic Engineering
Authors: Nagabhushan Tattanahalli , Narula Satwant 
Published: February 2004

AbstractThe article contains sections titled:1.Introduction2.DNA Cloning Techniques2.1.Cloning Genomic DNA Fragments inEscherichia coli2.1.1.Plasmids as Cloning Vectors2.1.2.Bacteriophage Lambda as a Cloning Vector2.1.3.Cosmids as Cloning Vectors2.1.4.Bacteriophage M13 as a Cloning Vector2.2.Synthesis of cDNA3.Methods for Screening and Identifying Recombinant Clones from a Library3.1.Nucleic Acid Hybridization3.2.Immunodetection Techniques3.3.Sequencing Techniques for DNA4.Expression of Recombinant Clones4.1.Heterologous Gene Expression in Prokaryotes4.1.1.Escherichia coli4.1.2.Bacillus subtilis4.2.Heterologous Gene Expression in Lower Eukaryotes (Fungi)4.2.1.Yeast (Saccharomyces cerevisiae)4.2.2.Other Yeast Systems4.2.3.Filamentous Fungi4.3.Heterologous Gene Expression in Higher Eukaryotes4.3.1.Mammalian Cells4.3.1.1.Vectors4.3.1.2.Promoters and Enhancers4.3.1.3.Chromosomal Gene Amplification4.3.2.Insect Systems4.3.3.Plant Systems4.3.3.1.Plasmid Vectors4.3.3.2.Plant Promoters5.Applications of Recombinant DNA Technology5.1.Therapeutic Agents5.2.Vaccines5.3.Genetically Altered Organisms5.3.1.Transgenic Animals5.3.2.Transgenic Plants5.4.Gene Therapy5.5.Diagnostics6.Regulatory and Safety Aspects7.Glossary of Special Terms
Nucleic Acids
Authors: Burtscher Helmut , Berner Sibylle , Seibl Rudolf , Mühlegger Klaus 
Published: February 2004

AbstractThe article contains sections titled:1.Introduction2.Structure2.1.Structure of DNA2.2.Structure of RNA3.Properties3.1.Physical and Chemical Properties3.2.Interaction with Proteins4.Biosynthesis and Biological Function4.1.DNA Replication4.2.Gene Expression4.2.1.Transcription4.2.2.Translation4.3.Modification and Degradation4.4.Recombination4.5.DNA Repair4.6.Nucleic Acids as Enzymes5.Isolation, Purification, and Transfer6.Analysis of Nucleic Acids7.Chemical Synthesis7.1.Synthesis Strategy7.2.Protecting Groups7.3.Functionalization of the Support7.4.Methods of Synthesis7.5.Cleavage of Protecting Groups and Purification of Oligonucleotides7.6.Synthesis of Modified Oligonucleotides8.Uses8.1.Hybridization Techniques for Nucleic Acid Detection8.2.Labeling and Detection Systems8.3.Amplification Systems8.4.Applications of Probe Technology9.Nucleosides and Nucleotides9.1.Nucleosides9.2.Nucleotides9.3.Therapeutically Important Nucleoside and Nucleotide Derivatives
Process‐Scale Chromatography
Authors: Jagschies Günter 
Published: February 2004

AbstractThe article contains sections titled:1.Introduction2.Chromatographic Techniques2.1.Adsorptive Methods2.1.1.Ion‐Exchange Chromatography2.1.2.Affinity Chromatography2.1.3.Hydrophobic Interaction Chromatography2.1.4.Reversed Phase Chromatography2.2.Gel Filtration3.Downstream Strategy3.1.Number of Preparative Steps3.2.Preparation of an Optimal Raw Material3.3.Development of a Chromatographic Purification System3.3.1.Screening of Chromatographic Methods (Method Scouting)3.3.1.1.The Gel Bank3.3.1.2.Experimental Data3.3.2.Logical Sequence of Chromatographic Steps3.3.2.1.Selection Criteria3.3.2.2.The Starting Step3.3.2.3.Subsequent Steps4.Optimization4.1.Purpose of Optimization4.2.Optimization Parameters4.2.1.Resolution4.2.2.Throughput4.3.Optimization of Ion‐Exchange Chromatography4.4.Optimization of Affinity Chromatography4.5.Optimization of Hydrophobic Interaction Chromatography4.6.Optimization of Gel Filtration5.Scaling Up5.1.Transfer Protocol5.2.Practical Examples and Case Studies5.3.Dimensioning of a Purification Cycle6.Process‐Scale Chromatography Plants6.1.Basic Design Requirements6.2.Plant Design6.2.1.The Chromatography Column6.2.2.Process Monitoring6.2.3.Pumps and Valves6.2.4.Automation and Safety Devices6.3.Effects of Apparatus on Separation7.Quality Assurance8.Developments
Freeze‐Drying
Authors: Oetjen Georg‐Wilhelm 
Published: February 2004

AbstractThe article contains sections titled:1.Introduction1.1.Goals of Industrial Freeze‐Drying1.2.Steps of the freeze‐drying process1.3.Chemical Engineering Tasks in Industrial Freeze‐Drying2.Process Steps2.1.Freezing2.2.Main Drying2.3.Transition from Main to Secondary Drying (SD)2.4.Secondary Drying2.5.Packing and Storage3.Temperatures and Pressures3.1.Barometric Temperature Measurement3.2.Pressure During Secondary Drying3.3.Water‐Vapor Flow3.4.Residual Moisture Content3.5.Uniformity of Temperatures, Pressures, and Product4.Structures of Frozen and Dried Products4.1.Influence of Freezing Method and Excipients4.2.Methods of Structure Analysis5.Industrial Freezing and Freeze‐drying Installations5.1.For Pharmaceutical Products5.2.Regulatory Requirements for Pharmaceutical Plants5.3.Food Plants5.4.Process Automation5.4.1.Prerequisites for Process and Plant Automation5.4.2.Control of the Process and the Plant by Thermodynamic Data Measured During the Process: Thermodynamic Lyophilization Control5.4.3.Transfer of Pilot Plant Data to Production6.Some Examples of Freeze‐drying Processes6.1.For Pharmaceuticals6.1.1.Process Reproducibility6.1.2.Shorter Drying Cycle6.1.3.Selection of Exipients6.2.For Food6.3.For Metal Oxides, Ceramic Powders7.Economic and Social Aspects, Outlook
Materials Design for Acoustic Liners: an Example of Tailored Multifunctional Materials
Authors: Gasser S. , Brechet Y. , Paun F. 
Published: February 2004

AbstractRelying on a model allowing to predict mechanical properties and acoustic absorption of a regular f.c.c stacking of hollow spheres, and on a functional analysis of acoustic liners for airplane engines, a methodology for optimal design of a taylored multifunctional material is proposed.
Powder Metallurgical Processing of Intermetallic Gamma Titanium Aluminides
Authors: Gerling R. , Clemens H. , Schimansky F.P. 
Published: February 2004

AbstractIntermetallic γ‐TiAl‐based alloys represent a new class of light‐weight structural materials for use at high temperatures. Because of their unique properties these alloys are considered for applications in aerospace and automotive industries. During the last decade both, alloy development and materials processing progressed significantly. New materials and powder metallurgy (PM) have formed a symbiosis since many decades. In fact, PM is an ancient technology which has been used for the processing for almost every metal or ceramic material. Therefore, it is hardly surprising that PM plays an important role in research and development of γ‐TiAl‐based alloys.
Heavy Metals in Saale Sediments — Changes in the Contamination since 1991
Authors: Zerling Lutz , Hanisch Christiane , Junge Frank W. , Müller Ansgar 
Published: February 2004

AbstractBased on the hydrographical and geological conditions of the river Saale catchment area, the regional geogenic background values are given for heavy metals in fluviatile sediments. They serve as a yardstick for evaluating the current sediment load of the Saale. Compared with the data from the 1990s, level reductions in the Saale can only be proven for the main contaminants Hg and Cr. By contrast, heavy metal levels in the formerly highly contaminated Weiße Elster river basin have clearly decreased, in particular Cd, Zn, Ag, and U. At the same time, increased manganese levels throughout the river system indicate a reduction in organic loads and an increase in oxygen levels.
The Difficult Assessment of Heavy Metal Contamination of Soils and Plants in Elbe River Floodplains
Authors: Krüger Frank , Gröngröft Alexander 
Published: February 2004

AbstractThe investigations on total sums of heavy metals indicated that topsoils in the floodplains in the German part of the river Elbe are in part markedly enriched. The contamination exceeds the action values of the Federal Soil Protection and Contaminated Site Ordinance. Looking on known concentrations of heavy metals in the pasture vegetation, however, threshold values for fodder are not exceeded in most cases. As livestock takes up a part of contaminants by inhalation and ingestion of soil particles and as the contamination in the vegetation is variable in space and time, the actual risk of heavy metal transfer in the food chain has needs to be studied.
Entry and Deposits of Suspended Particulate Matter in Groyne Fields of the Middle Elbe and its Ecological Relevance
Authors: Schwartz René , Kozerski Hans‐Peter 
Published: February 2004

AbstractGroynes are widespread in the Middle Elbe River. They are important for navigation during low water. Due to the significant decrease of the flow velocity in comparison to the main stream, sedimentation of fine organic matter in the groyne fields (the area between two groynes) is high. The amount and location of sedimentation depend on hydraulic processes. The present paper presents the results of the actual (recent) sedimentation, and of the matter deposited in a typical groyne field in the Middle Elbe at Havelberg (German navigation km 420.9/river length 785.4). Furthermore, the development of water quality and suspended matter is described by the interpretation of data from an adjacent official water quality measuring point. From an ecological point of view, the high loads of nutrients and pollutants of the fine‐grained sediment (mud) are of special interest. A close correlation was observed between the nutrient and pollutant load with the fine‐grain size percentage and the content of particulate organic matter (POM). Groyne fields act as temporary sediment deposits, and are a latent danger to the ecosystem river Elbe. During construction work carried out at the river and extreme floods the mud could be remobilized, leading to a decrease in the water quality of the Elbe. Therefore, it is desirable that the organic mud should be removed from the river and deposited in a controlled landfill.
Investigations into the Distribution of Element Concentrations in a Recent Dam and their Seasonal and Hydrographical Correlation (Bitterfelder Muldestausee, Saxony‐Anhalt)
Authors: Junge Frank W. , Jendryschik Karl 
Published: February 2004

AbstractExamination of the levels of dissolved matter in layered water bodies (case I) of the Bitterfelder Muldestausee (dam) showed a specific distribution of the element concentrations largely depending on the ion potential (inner migration factor) and the degree of saturation for oxygen (outer migration factor). During the summer, the elements (and/or ions) Al, PO‐P, V, As, Mo, B, Ce, Y, Zr, Sb, Cr characterized by a high ion potential and a high energy coefficient chiefly accumulate in the epilimnion rich in oxygen. However, the hypolimnion, which is free of oxygen, features increased concentrations of the dissolved elements (and/or ions) Mn, Co, NH‐N, Zn, Cd, Cu, and Ni. From the beginning of the hydrologic winter (case II), the lake water is completely intermingled with the cold incoming Mulde water streams, and the anoxic conditions of the deep water zones disappear. The distribution of element concentrations intermingled in the water body is characterized by processes of dilution and increases in concentration as well as by element‐specific precipitation and reverse dissolution.
Pore Water Composition as Device for the Detection of Origin and Flow Direction of Soil Water in Alluvial Soils of the Middle Elbe River
Authors: Schwartz René , Gröngröft Alexander , Miehlich Günter 
Published: February 2004

AbstractThe aim of the present article was to show the spreading of the Elbe‐borne pore water in the diked area of the lower Middle Elbe River floodplain at Lenzen (Brandenburg). The distribution was exhibited by comparing the composition of the river water of the rivers Elbe and Löcknitz, as well as groundwater and soil solution of the adjacent floodplain. It became evident that the sites in the recent flood area did not inevitably reflect soil solution compositions of closest similarity to conditions of the Elbe water. The high relative elevation of the stream bank and the plateau site in relation to the mean water level of the river Elbe and their dominant sandy substrate caused a great influence of precipitation water. Within the diked area of the floodplain, the soil solution analyses were sufficient to derive the maximum infiltration of the stream water. At 250 m distance of the Elbe dike, the soil solution still clearly exhibited the features of the Elbe water, and at 450 m distance, a transition zone equally influenced by the groundwater of the river Elbe and the river Löcknitz was detected. Finally, at 1.3 km distance from the dike in the relictic floodplain, the groundwater was definitely Löcknitz‐borne, although the hydraulic potentials of the Elbe were still effective. The presented results will allow to make predictions about the effects of the imminent dike realignment to the soil solution on the adjacent floodplain.
Colloidal Particles in Sediment Pore Waters: Particle Size Distributions and Associated Element Size Distribution in Anoxic and Re‐oxidized Samples, Obtained by FFF‐ICP‐MS Coupling
Authors: v. d. Kammer Frank , Baborowski Martina , Tadjiki Soheyl , v. Tümpling jr. Wolf 
Published: February 2004

AbstractPore water samples from sediment cores of the rivers Saale and Elbe were examined for variations of colloidal heavy metal associations during transition from anoxic to oxic conditions. Asymmetric flow‐field flow fractionation coupled to ICP‐MS was used to collect size distributions and element‐size distributions simultaneously. The data obtained reveal an increasing amount of colloidal bound main and trace elements in the pore waters during oxidation. Although there was a significant trend to increasing colloid concentrations and colloidal bound heavy metals over the observed 48 hour period of oxidation, differences between both samples were obvious.
Depth Distribution of Chlorinated and Polycyclic Aromatic Hydrocarbons in Floodplain Soils of the River
Authors: Witter Barbara , Winkler Marcus , Friese Kurt 
Published: February 2004

AbstractDepth profiles of various organic micropollutants were measured in floodplain soils of the river Elbe, Germany. The study area lies in the former East Germany (GDR) and displays elevated concentrations of pesticides and polycyclic aromatic hydrocarbons. Depth distributions were found to vary at different sampling points and among the individual compounds, which could only partly be explained by comparing normalized concentrations (organic carbon). Metabolization, mobilization, and effects of sedimentation and erosion also need to be taken into account to understand the contaminant patterns found in the different profiles.
ELBIS, an Internet Information System on the Water Quality of the River Elbe
Authors: Frank Barbara , Geschwandtner Dirk , Janson Katja , Löffler Joachim 
Published: February 2004

AbstractThe Elbe information system ELBIS provides an elaborate view of the water quality of the Elbe river system. Since July 2001 it can be used by the general public via internet. www.elbis.de supplies information on the water quality and related topics for the river Elbe. The geographical information system (GIS) ELBIS is based upon extensive data from measuring campaigns. The ARGE Elbe (Arbeitsgemeinschaft zur Reinhaltung der Elbe/Elbe River Water Quality Board) supplies the measured values of 218 different variables. The ELBIS generally includes data from 1994 onwards, for the measuring point Schnackenburg, however, the values are available back to 1985. Annual data updates of the database would be necessary to ensure the system's topicality. The continuous time series enables the assessment of the water pollution load of the river Elbe.In order to make the information available to a broad circle of users, ELBIS was created as an internet information system. To simplify its usage a broad meta‐information and navigation concept was developed. The user interface enables data to be accessed by laymen as well as specialists. An important element of the user interface is the geographical component: Via a digital map the user can specify which area he or she is interested in. The data basis of the ELBIS is held in a database management system. Thus new data can be added easily.