Various Applications (various + application)

Distribution by Scientific Domains
Distribution within Polymers and Materials Science


Selected Abstracts


Laser Sources for Ultrashort Pulses , Oscillators and Amplifiers for Various Applications

LASER TECHNIK JOURNAL, Issue 1 2007
Rüdiger Paschotta Dr.
[source]


Ricci flows and infinite dimensional algebras

FORTSCHRITTE DER PHYSIK/PROGRESS OF PHYSICS, Issue 6-7 2004
I. Bakas
The renormalization group equations of two-dimensional sigma models describe geometric deformations of their target space when the world-sheet length changes scale from the ultra-violet to the infra-red. These equations, which are also known in the mathematics literature as Ricci flows, are analyzed for the particular case of two-dimensional target spaces, where they are found to admit a systematic description as Toda system. Their zero curvature formulation is made possible with the aid of a novel infinite dimensional Lie algebra, which has anti-symmetric Cartan kernel and exhibits exponential growth. The general solution is obtained in closed form using Bäcklund transformations, and special examples include the sausage model and the decay process of conical singularities to the plane. Thus, Ricci flows provide a non-linear generalization of the heat equation in two dimensions with the same dissipative properties. Various applications to dynamical problems of string theory are also briefly discussed. Finally, we outline generalizations to higher dimensional target spaces that exhibit sufficient number of Killing symmetries. [source]


Brief Overview of BioMicroNano Technologies

BIOTECHNOLOGY PROGRESS, Issue 1 2005
Paul L. Gourley
This paper provides a brief overview of the fields of biological micro-electromechanical systems (bioMEMs) and associated nanobiotechnologies, collectively denoted as BioMicroNano. Although they are developing at a very rapid pace and still redefining themselves, several stabilized areas of research and development can be identified. Six major areas are delineated, and specific examples are discussed and illustrated. Various applications of the technologies are noted, and potential market sizes are compared. [source]


Mapping cityscapes into cyberspace for visualization

COMPUTER ANIMATION AND VIRTUAL WORLDS (PREV: JNL OF VISUALISATION & COMPUTER ANIMATION), Issue 2 2005
Jiang Yu Zheng
Abstract This work establishes a cyberspace of a real urban area for visiting on the Internet. By registering entire scenes along every street and at many locations, viewers can visually travel around and find their destinations in cyberspace. The issues we discuss here are mapping of a large-scale area to image domains in a small amount of data, and effective display of the captured scenes for various applications. Route Panoramas captured along streets and panoramic views captured at widely opening sites are associated to a city map to provide navigation functions. This paper focuses on the properties of our extended images,route panorama, addressing the archiving process applied to an urban area, an environment developed to transmit image data as streaming media, and display for scene traversing on the WWW in real time. The created cyberspaces of urban areas have broad applications such as city tour, real estate searching, e-commerce, heritage preservation, urban planning and construction, and vehicle navigation. Copyright © 2005 John Wiley & Sons, Ltd. [source]


A perspective factorization method for Euclidean reconstruction with uncalibrated cameras

COMPUTER ANIMATION AND VIRTUAL WORLDS (PREV: JNL OF VISUALISATION & COMPUTER ANIMATION), Issue 4 2002
Mei Han
Abstract Structure from motion (SFM), which is recovering camera motion and scene structure from image sequences, has various applications, such as scene modelling, robot navigation, object recognition and virtual reality. Most of previous research on SFM requires the use of intrinsically calibrated cameras. In this paper we describe a factorization-based method to recover Euclidean structure from multiple perspective views with uncalibrated cameras. The method first performs a projective reconstruction using a bilinear factorization algorithm, and then converts the projective solution to a Euclidean one by enforcing metric constraints. The process of updating a projective solution to a full metric one is referred as normalization in most factorization-based SFM methods. We present three normalization algorithms which enforce Euclidean constraints on camera calibration parameters to recover the scene structure and the camera calibration simultaneously, assuming zero skew cameras. The first two algorithms are linear, one for dealing with the case that only the focal lengths are unknown, and another for the case that the focal lengths and the constant principal point are unknown. The third algorithm is bilinear, dealing with the case that the focal lengths, the principal points and the aspect ratios are all unknown. The results of experiments are presented. Copyright © 2002 John Wiley & Sons, Ltd. [source]


A Windows-based interface for teaching image processing

COMPUTER APPLICATIONS IN ENGINEERING EDUCATION, Issue 2 2010
Melvin Ayala
Abstract The use of image processing in research represents a challenge to the scientific community interested in its various applications but is not familiar with this area of expertise. In academia as well as in industry, fundamental concepts such as image transformations, filtering, noise removal, morphology, convolution/deconvolution among others require extra efforts to be understood. Additionally, algorithms for image reading and visualization in computers are not always easy to develop by inexperienced researchers. This type of environment has lead to an adverse situation where most students and researchers develop their own image processing code for operations which are already standards in image processing, a redundant process which only exacerbates the situation. The research proposed in this article, with the aim to resolve this dilemma, is to propose a user-friendly computer interface that has a dual objective which is to free students and researchers from the learning time needed for understanding/applying diverse imaging techniques but to also provide them with the option to enhance or reprogram such algorithms with direct access to the software code. The interface was thus developed with the intention to assist in understanding and performing common image processing operations through simple commands that can be performed mostly by mouse clicks. The visualization of pseudo code after each command execution makes the interface attractive, while saving time and facilitating to users the learning of such practical concepts. © 2009 Wiley Periodicals, Inc. Comput Appl Eng Educ 18: 213,224, 2010; Published online in Wiley InterScience (www.interscience.wiley.com); DOI 10.1002/cae.20171 [source]


Microautosamplers for discrete sample injection and dispensation

ELECTROPHORESIS, Issue 9 2005
Chun-Wei Huang
Abstract Microfluidic systems show considerable potential for use in the continuous reaction and analysis of biosamples for various applications, such as drug screening and chemical synthesis. Typically, microfluidic chips are externally connected with large-scale autosamplers to inject specific volumes of discrete samples in the continuous monitoring and analysis of multiple samples. This paper presents a novel microelectromechanical system (MEMS)-based autosampler capable of performing the discrete injection and dispensation of variable-volume samples. This microdevice can be integrated with other microfluidic devices to facilitate the continuous monitoring and analysis of multiple biosamples. By means of electroosmotic focusing and switching controlled by the direct application of electric sources on specific fluid reservoirs, a precise sample volume can be injected into the specified outlet port. Fluorescence dye images verify the performance of the developed device. An injection-and-washing scheme is developed to prevent cross-contamination during the continuous injection of different samples. This approach renders feasible the injection of several discrete samples using a single microchip. Compared to its large-scale counterparts, the developed microautosampler is compact in size, has low fabrication costs, is straightforward to control, and most importantly, is readily integrated with other microfluidic devices (e.g., microcapillary electrophoresis chips) to form a microfluidic system capable of the continuous monitoring and analysis of bioreactions. The proposed microautosampler could be promising towards realizing the micrototal analysis system (,-TAS) concept. [source]


Quantitative measurement of collagen methylation by capillary electrophoresis

ELECTROPHORESIS, Issue 20 2004
Jing Zhang
Abstract Collagen methylation has been exploited in various applications involving living cells. We have observed correlation between the collagen methylation with the rate of cell proliferation in three-dimensional (3-D) microenvironment. To quantify the degree of collagen methylation, we have developed a capillary zone electrophoresis method. Using a polyvinyl alcohol-coated fused-silica capillary and UV detection at 200 nm, we have optimized pH and separated the native collagen into three major bands in phosphate buffer (50 mM, pH 2.5) with 0.05% hydroxypropylmethylcellulose. Under these conditions, the methylated collagens were separated into four major bands, which changed with different methylation reaction conditions. We propose an index to quantify the degree of collagen methylation that also correlates with their effects on cell proliferation. [source]


Life cycle assessment: An international experience

ENVIRONMENTAL PROGRESS & SUSTAINABLE ENERGY, Issue 2 2000
Mary Ann Curran
Life Cycle Assessment (LCA) is used to evaluate environmental burdens associated with a product, process or activity by identifying and quantifying relevant inputs and outputs of the defined system and evaluating their potential impacts. This article outlines the four components that comprise LCA (goal definition, inventory, impact assessment and interpretation) and addresses various applications of LCA within industry and government. Included are references to several resources that may be used to better understand and apply LCA, such as books, journals, software programs and internet websites. [source]


Volatile compounds of original African black and white shea butter from Tchad and Cameroon

EUROPEAN JOURNAL OF LIPID SCIENCE AND TECHNOLOGY, Issue 7 2006
Sabine Krist
Abstract Shea butter is used as an edible vegetable fat in many African countries. It can be utilized as a substitute or complete replacement for cocoa butter in various applications and plays an important role in traditional African medicinal practice. Although detection of volatile compounds by solid-phase micro-extraction gas-chromatography mass-spectroscopy (SPME-GC-MS) is a very reliable and reproducible technique, which can be used as an important part of authenticity checking, production monitoring and contamination detection, no published data about volatile compounds of shea butter are available so far. In this investigation, the characteristic volatiles in the headspace of original African shea butter samples were identified by using SPME-capillary-GC coupled to a mass selective detector. Almost 100,different volatile components were identified, e.g. fatty acids, saturated and unsaturated aldehydes and ketones, terpenes, and typical Maillard reaction products such as methylfuranes and pyrazines. Furthermore, the samples have been olfactorily evaluated by a panel of professional flavorists and trained analytical chemists. It can be stated that variations in processing conditions of shea butter result in considerable differences in the composition of headspace volatiles, detected by SPME-GC-MS and human olfaction. [source]


A Novel Process for the Manufacture of Auxetic Foams and for Their re-Conversion to Conventional Form,

ADVANCED ENGINEERING MATERIALS, Issue 7 2009
Joseph N. Grima
Images showing the microstructure of conventional and auxetic foams produced through the traditional thermo,mechanical process and the novel chemo,mechanical process. Auxetic foams exhibit the unusual property of becoming fatter which when stretched a property which makes them superior to conventional foams in various applications ranging from smart tunable filters to vibration-proofing materials. [source]


Harnessing Surface Wrinkle Patterns in Soft Matter

ADVANCED FUNCTIONAL MATERIALS, Issue 16 2010
Shu Yang
Abstract Mechanical instabilities in soft materials, specifically wrinkling, have led to the formation of unique surface patterns for a wide range of applications that are related to surface topography and its dynamic tuning. In this progress report, two distinct approaches for wrinkle formation, including mechanical stretching/releasing of oxide/PDMS bilayers and swelling of hydrogel films confined on a rigid substrate with a depth-wise modulus gradient, are discussed. The wrinkling mechanisms and transitions between different wrinkle patterns are studied. Strategies to control the wrinkle pattern order and characteristic wavelength are suggested, and some efforts in harnessing topographic tunability in elastomeric PDMS bilayer wrinkled films for various applications, including tunable adhesion, wetting, microfluidics, and microlens arrays, are highlighted. The report concludes with perspectives on the future directions in manipulation of pattern formation for complex structures, and potential new technological applications. [source]


High-Resolution Patterning of Hydrogels in Three Dimensions using Direct-Write Photofabrication for Cell Guidance

ADVANCED FUNCTIONAL MATERIALS, Issue 22 2009
Stephanie K. Seidlits
Abstract The development of three-dimensional, spatially defined neuronal cultures that mimic chemical and physical attributes of native tissue is of considerable interest for various applications, including the development of tailored neuronal networks and clinical repair of damaged nerves. Here, the use of multiphoton excitation to photocrosslink protein microstructures within three-dimensional, optically transparent hydrogel materials, such as those based on hyaluronic acid, is reported. Multiphoton excitation confines photocrosslinking to a three-dimensional voxel with submicron spatial resolution, enabling fabrication of protein matrices with low- to sub-micrometer feature sizes by scanning the focus of a laser relative to the reagent solution. These methods can be used to create complex three-dimensional architectures that provide both chemical and topographical cues for cell culture and guidance, providing for the first time a means to direct cell adhesion and migration on size scales relevant to in vivo environments. Using this approach, guidance of both dorsal root ganglion cells (DRGs) and hippocampal neural progenitor cells (NPCs) along arbitrary, three-dimensional paths is demonstrated. [source]


Efficient production of monoclonal antibodies recognizing specific structures in Caenorhabditis elegans embryos using an antigen subtraction method

GENES TO CELLS, Issue 7 2008
Kazumasa Takeda
Monoclonal antibodies (mAbs) have been widely used to probe molecular components of specific cell types or cellular structures. We have developed a method to enrich antigens of low abundance in heterogeneous molecule mixtures by subtracting abundant antigens. The subtracted immunogen mixture is then used for immunization, which significantly increases the production of mAbs that exhibit specific staining patterns. By applying this "antigen subtraction" method to the embryonic extract of Caenorhabditis elegans, we have successfully isolated 35 mAbs that recognize specific structures, including P granules, muscles, the pharynx, and subsets of hypodermal cells; some of the mAbs revealed previously unreported cellular structures. This antigen subtraction approach can be used in various applications to produce mAbs against relatively scarce antigens in complex molecular mixtures. The mAbs will be useful tools for developmental and cell biological studies. [source]


Gravity gradiometer systems , advances and challenges

GEOPHYSICAL PROSPECTING, Issue 4 2009
Daniel DiFrancesco
ABSTRACT The past few years have witnessed significant advances and unparalleled interest in gravity gradiometer instrument technology as well as new deployment scenarios for various applications. Gravity gradiometry is now routinely considered as a viable component for resource exploration activities as well as being deployed for global information gathering. Since the introduction of the torsion balance in the 1890s, it has been recognized that gravity gradient information is valuable , yet difficult and time-consuming to obtain. The recent acceptance and routine use of airborne gravity gradiometry for exploration has inspired many new technology developments. This paper summarizes advances in gravity gradient sensor development and also looks at deployment scenarios and gradiometer systems that have been successfully fielded. With projected improved system performance on the horizon, new challenges will also come to the forefront. Included in these challenges are aspects of instrument and system intrinsic noise, vehicle dynamic noise, terrain noise, geologic noise and other noise sources. Each of these aspects is briefly reviewed herein and recommendations for improvements presented. [source]


Dynamic and Reversible Organization of Zeolite L Crystals Induced by Holographic Optical Tweezers

ADVANCED MATERIALS, Issue 37 2010
Mike Woerdemann
Organization and patterning of zeolite L crystals with their unique properties such as their one-dimensional nano channel system is of highest topical interest with various applications in many areas of science. We demonstrate full three-dimensional optical control of single zeolite L crystals and for the first time fully reversible, dynamic organization of a multitude of individually controlled zeolite L crystals. [source]


One-Step Exfoliation Synthesis of Easily Soluble Graphite and Transparent Conducting Graphene Sheets

ADVANCED MATERIALS, Issue 43 2009
Jong Hak Lee
Easily soluble expanded graphite (see figure) is synthesized in a one-step exfoliation process that can be used for the lowcost mass production of graphene for various applications because of the simplicity and speed of the process. The graphene obtained is sufficiently expanded to be dispersed in aqueous solutions with an ordinary surfactant and in organic solvents. [source]


Lanthanide Nanocrystals: Colloidal Tm3+/Yb3+ -Doped LiYF4 Nanocrystals: Multiple Luminescence Spanning the UV to NIR Regions via Low-Energy Excitation (Adv. Mater.

ADVANCED MATERIALS, Issue 40 2009
40/2009)
LiYF4 nanoparticles co-doped with thulium and ytterbium ions show multiple emissions in the region covering the ultraviolet to the near-infrared following excitation with low-energy radiation via a multiphoton process known as upconversion, in work reported by John Capobianco and co-workers on p. 4025. These versatile diamond-shaped nanoparticles have been identified as candidates for potential integration in various applications including cell labeling and imaging, solution-based fast scintillation, as well as anti-counterfeiting. [source]


Some Parameters of Correlated Current and Radiated Field Pulses from Lightning to the Gaisberg Tower

IEEJ TRANSACTIONS ON ELECTRICAL AND ELECTRONIC ENGINEERING, Issue 1 2010
Hannes Pichler Non-member
Abstract Simultaneous measurements of lightning current and associated radiated electromagnetic field are of fundamental interest for various applications in lightning research. These data can be used for the evaluation of return stroke (RS) models or to investigate the so-called tower effect when lightning hits an elevated object. In this paper, we show the results of simultaneous measurements of current pulses from lightning strikes on the instrumented Gaisberg tower (Austria) and the correlated vertical E-field components at a distance of 78.8 and 108.7 km, respectively. We have analyzed some main lightning current parameters (peak current Ip, 30,90% rise time TI_30-90, and full width at half maximum TI_FWHM and the time-correlated field waveform parameters (Ep, 30,90% rise time TE_30-90, TE_FWHM, and the peak-to-zero time TE_PTZ. With a geometric mean of TI_FWHM = 19 ,s and Ip = 9.6 kA (N = 73) of the RS current pulses used in this study, those strokes are very similar to the strokes in triggered lightning in Florida and Alabama1. With a TE_PTZ of about 10 µs, the zero-crossing time of the radiated E-fields from the tower strokes are significantly shorter than the typical values of 30 , 40 µs (e.g.2). Correlation between the current and field parameters TI_FWHM versus TE_FWHM and TE_PTZ, respectively, is low (R2 = 0.29 and 0.14). We assume that the relatively short lightning channel in the case of the RSs in object-triggered upward flashes is the main reason for the observed short zero-crossing time. Copyright © 2010 Institute of Electrical Engineers of Japan. Published by John Wiley & Sons, Inc. [source]


Photocatalytic Carbon-Nanotube,TiO2 Composites

ADVANCED MATERIALS, Issue 21 2009
Karran Woan
Abstract The literature and advances in photocatalysis based on the combination of titania (TiO2) and carbon nanotubes is presented. The semiconductor basis for photocatalysis is introduced for anatase and rutile. Furthermore, the proposed mechanisms of catalytic enhancement resulting from the pairing of the titania semiconductor with either metallic, semiconducting, or defect-rich carbon nanotubes (CNT) is discussed. Differences are apparent for the mixtures and chemically bonded CNT,TiO2 composites. The article then highlights the recent advances in the synthesis techniques for these composites and their photocatalytic reactions with organic, inorganic, and biological agents. Finally, various applications and challenges for these composite materials are reported. [source]


Multiscale approach to geo-composite cellular structures subjected to rock impacts

INTERNATIONAL JOURNAL FOR NUMERICAL AND ANALYTICAL METHODS IN GEOMECHANICS, Issue 13 2007
François Nicot
Abstract Geo-composite cellular structures are an efficient technological solution for various applications in civil engineering. This type of structure is particularly well adapted to resisting rockfalls and can act as a defensive structure. However, the design of such structures is for the most part empirically based; this lack of research-based design stagnates optimization and advanced development. In this paper, the mechanical behaviour of a geo-composite cellular structure is investigated using a multi-scale approach, from the individual cell made up of an assembly of rocky particles contained in a wire netting cage to the entire structure composed of a regular array of cells. Based on discrete modelling of both the cell and structure scales, a computational tool has been developed for design purposes. Copyright © 2007 John Wiley & Sons, Ltd. [source]


On bipolarity in argumentation frameworks

INTERNATIONAL JOURNAL OF INTELLIGENT SYSTEMS, Issue 10 2008
L. Amgoud
In this article, we propose a survey of the use of bipolarity in argumentation frameworks. On the one hand, the notion of bipolarity relies on the presence of two kinds of entities that have a diametrically opposed nature and that represent repellent forces (a positive entity and a negative entity). The notion exists in various domains (for example with the representation of preferences in artificial intelligence, or in cognitive psychology). On the other hand, argumentation process is a promising approach for reasoning, based on the construction and the comparison of arguments. It follows five steps: building the arguments, defining the interactions between these arguments, valuating the arguments, selecting the most acceptable arguments and, finally, drawing a conclusion. Using the nomenclature proposed by Dubois and Prade, this article shows on various applications, and with some formal definitions, that bipolarity appears in argumentation (in some cases if not always) and can be used in each step of this process under different forms. © 2008 Wiley Periodicals, Inc. [source]


Properties and performance of orthogonal neural network in function approximation

INTERNATIONAL JOURNAL OF INTELLIGENT SYSTEMS, Issue 12 2001
Chieh F. Sher
Backpropagation neural network has been applied successfully to solving uncertain problems in many fields. However, unsolved drawbacks still exist such as the problems of local minimum, slow convergence speed, and the determination of initial weights and the number of processing elements. In this paper, we introduce a single-layer orthogonal neural network (ONN) that is developed based on orthogonal functions. Since the processing elements are orthogonal to one another and there is no local minimum of the error function, the orthogonal neural network is able to avoid the above problems. Among the five existing orthogonal functions, Legendre polynomials and Chebyshev polynomials of the first kind have the properties of recursion and completeness. They are the most suitable to generate the neural network. Some typical examples are given to show their performance in function approximation. The results show that ONN has excellent convergence performance. Moreover, ONN is capable of approximating the mathematic model of backpropagation neural network. Therefore, it should be able to be applied to various applications that backpropagation neural network is suitable to solve. © 2001 John Wiley & Sons, Inc. [source]


Split-component PML absorbing conditions for SS-TLM

INTERNATIONAL JOURNAL OF NUMERICAL MODELLING: ELECTRONIC NETWORKS, DEVICES AND FIELDS, Issue 3 2004
S. Le Maguer
Abstract Known as alternate direct implicit (ADI) or split-step (SS) schemes, a new class of time-domain algorithms has recently been proposed. Their salient feature concerns their numerical stability, regardless the time-step used. Thus, significant computational advantages can be obtained when non-uniform mesh is used. To study open structures or determine S-parameters, absorbing boundary conditions (ABC) have to be used. The perfectly matched layers (PML) technique based on split field component is implemented for the SS-TLM algorithm. The complete set of updating equations is provided and the new PML is validated. It is shown to provide high accuracy even better than that of classical PML-TLM scheme. In addition, it is found that using a high time-step does not seem to degrade significantly the accuracy of PML. Thus, the PML technique is very well adapted to SS-TLM as confirmed by various applications. Finally, unlike all classical TLM-PML schemes, the technique is found to be stable. Copyright © 2004 John Wiley & Sons, Ltd. [source]


Degradation of aramid fibers under alkaline and neutral conditions: Relations between the chemical characteristics and mechanical properties

JOURNAL OF APPLIED POLYMER SCIENCE, Issue 5 2010
G. Derombise
Abstract Aramid fibers are high-performance materials that have been used in various applications such as heat and cut protection, composites, rubber reinforcement, ropes and cables, and fabrics; today their use is proposed in geotextiles for alkaline ground reinforcement, and they have been used in cables for marine applications for a few years. However, there is a lack of experience with the long-term behavior of aramid fibers in wet and alkaline environments. Aging studies were therefore performed on Twaron 1000 fibers under different conditions (sea water, deionized water, pH 9, and pH 11). Hydrolytic degradation was evaluated with Fourier transform infrared and viscosimetry measurements, which were correlated with tensile test measurements. The tensile strength followed a logarithmic evolution with the aging time, whereas the modulus remained constant. A linear relation between the tensile strength and the reduced viscosity of the hydrolytically aged fibers is highlighted. Aging indicators are proposed that allow the hydrolytic degradation to be quantified. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2010 [source]


Preparation and optical properties of an all-polymer light modulator using colored N -isopropylacrylamide gel particles in a gel-in-gel system

JOURNAL OF APPLIED POLYMER SCIENCE, Issue 4 2007
Hiroaki Tsutsui
Abstract A novel all-polymer light modulator with a gel-in-gel system was developed. The gel-in-gel system was constructed with colored gel particles responsive to stimuli held independently in another stimuli-nonresponsive gel matrix. Well-known thermoresponsive N -isopropylacrylamide (NIPAM) gel particles containing a pigment were dispersed and fixed in an outer stimuli-nonresponsive gel matrix. When poly(vinyl alcohol),styrylpyridinium (PVA,SbQ) was used for the outer gel matrix, the light modulator showed excellent color-changing properties because the PVA,SbQ matrix was selectively formed around the NIPAM gel particles and the particles exhibited a large volume change in the matrix. The temperature when the outer gel matrix was formed affected the haze of the light modulator. When the outer gel matrix was formed in the swollen state of the NIPAM gels, the haze of a light modulator increased with heating. On the contrary, the haze of a light modulator prepared in the shrunken state of the NIPAM gels decreased with heating. The response time of the color change was less than 1 s. The gel-in-gel system made a very fast macroscopic color change, taking advantage of the fast response of the micrometer-sized gel particles. We believe that a light modulator with a gel-in-gel system may find various applications in optical devices. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 103: 2295,2303, 2007 [source]


Peer review in Nursing and Midwifery: a literature review

JOURNAL OF CLINICAL NURSING, Issue 4 2008
Amelia Rout MSc, BSc (Hons)
Aims and objectives., The Clinical Education Project investigated clinical education in nursing and midwifery settings. The aim of this phase was to investigate and evaluate the processes and outcomes of clinical assessment of preregistration nurses and midwives, focusing on the assessment interview, and to evaluate the feasibility of introducing peer review of the clinical assessment interview in acute clinical settings. Background., Peer review is common in many professional areas. The literature describes various applications of peer review and makes recommendations for its use. However, there is a shortage of studies investigating the use of peer review in nursing and midwifery education and practice. Design., The project involved a systematic literature review and a qualitative exploratory study. This article describes the first part of the study: a systematic literature review of peer review. The second part of the study is reported elsewhere. Methods., The systematic literature review investigated international articles written since 1994 that contained information on peer review in pre/post registration nursing and midwifery within higher education or practice. Results., From the available literature, 52 specific initiatives were analysed. The majority of articles originated in America and involved nursing staff working in secondary care settings. Fifty-one articles had missing information varying from not stating the sample size to not including information about evaluations. Conclusions., The literature review found that whilst peer review is commonplace in nursing and midwifery practice, there is a lack of robust literature about its use. Relevance to clinical practice., Peer review in clinical settings such as nursing and midwifery can facilitate the sharing of good practice and personal and professional growth. It allows participants to learn from each other and gain insight into their development. [source]


Conformational analysis of arginine in gas phase,A strategy for scanning the potential energy surface effectively

JOURNAL OF COMPUTATIONAL CHEMISTRY, Issue 3 2008
Sebastian Schlund
Abstract The determination of all possible low-lying energy conformers of flexible molecules is of fundamental interest for various applications. It necessitates a reliable conformational search that is able to detect all important minimum structures and calculates the energies on an adequate level of theory. This work presents a strategy to identify low-energy conformers using arginine as an example by means of a force-field based conformational search in combination with high-level geometry optimizations (RI-MP2/TZVPP+). The methods used for various stages in the conformational search strategy are shown and various pitfalls are discussed. We can show that electronic energies calculated on a DFT level of theory with standard exchange-correlation functionals strongly underestimate the intramolecular stabilization resulting from stacked orientations of the guanidine and carbonyl moiety of arginine due to the deficiency of DFT to describe dispersion effects. In this case by usage of electron correlation methods, low energy conformers comprising stacked arrangements that are counterintuitive become favorable. © 2007 Wiley Periodicals, Inc. J Comput Chem, 2008 [source]


Development of sonic technology for the daily cleansing of the skin

JOURNAL OF COSMETIC DERMATOLOGY, Issue 2 2006
Robert E Akridge PhD
Summary Even though many skin cleansing products are commercially available, the cleansing of the skin is dependent upon the user's diligence, compliance, and technique, which often results in inconsistent cleansing. When the skin is inadequately or excessively cleansed, the skin becomes compromised, sometimes leading to acute or chronic conditions that may require medical attention. A sonic skincare brush was developed to enhance and provide consistent skin cleansing while preventing the skin from becoming compromised. Utilizing a technology previously used to cleanse the oral cavity, the sonic skincare brush is optimized to work with the skin's own elasticity providing rapid oscillatory flexing of the infundibular opening. By oscillating at sonic speed the net result is the inelastic comedones become loosened and detached from the infundibular wall and are then cleared from the acroinfundibulum. Although additional clinical research into the various applications of sonic skin care technology is needed, utilization of sonic technology is now available for effectively and consistently cleansing the skin. [source]


Hairy Root and Its Application in Plant Genetic Engineering

JOURNAL OF INTEGRATIVE PLANT BIOLOGY, Issue 2 2006
Zhi-Bi Hu
Abstract Agrobacterium rhizogenes Conn. causes hairy root disease in plants. Hairy root-infected A. rhizogenes is characterized by a high growth rate and genetic stability. Hairy root cultures have been proven to be an efficient means of producing secondary metabolites that are normally biosynthesized in roots of differentiated plants. Furthermore, a transgenic root system offers tremendous potential for introducing additional genes along with the Ri plasmid, especially with modified genes, into medicinal plant cells with A. rhizogenes vector systems. The cultures have turned out to be a valuable tool with which to study the biochemical properties and the gene expression profile of metabolic pathways. Moreover, the cultures can be used to elucidate the intermediates and key enzymes involved in the biosynthesis of secondary metabolites. The present article discusses various applications of hairy root cultures in plant genetic engineering and potential problems associated with them. (Managing editor: Wei Wang) [source]