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Several Kinds (several + kind)
Selected AbstractsApplication of Multivariate curve resolution-alternating least square methods on the resolution of overlapping CE peaks from different separation conditionsELECTROPHORESIS, Issue 20 2007Fang Zhang Abstract Discussed in this paper is the development of a new strategy to improve resolution of overlapping CE peaks by using second-order multivariate curve resolution with alternating least square (second-order MCR-ALS) methods. Several kinds of organic reagents are added, respectively, in buffers and sets of overlapping peaks with different separations are obtained. Augmented matrix is formed by the corresponding matrices of the overlapping peaks and is then analyzed by the second-order MCR-ALS method in order to use all data information to improve the precision of the resolution. Similarity between the resolved unit spectrum and the true one is used to assess the quality of the solutions provided by the above method. 3,4-Dihydropyrimidin-2-one derivatives (DHPOs) are used as model components and mixed artificially in order to obtain overlapping peaks. Three different impurity levels, 100, 20, and 10% relative to the main component, are used. With this strategy, the concentration profiles and spectra of impurities, which are no more than 10% of the main component, can be resolved from the overlapping peaks without pure standards participant in the analysis. The effects of the changes in the components spectra in the buffer with different organic reagents on the resolution are also evaluated, which are slight and can thus be ignored in the analysis. Individual data matrices (two-way data) are also analyzed by using MCR-ALS and heuristic evolving latent projections (HELP) methods and their results are compared with those when MCR-ALS is applied to augmented data matrix (three-way data) analysis. [source] Hydrolytic Deallylation of N -Allyl Amides Catalyzed by PdII ComplexesEUROPEAN JOURNAL OF ORGANIC CHEMISTRY, Issue 30 2008Naoya Ohmura Abstract Hydrolytic deallylation of N -allyl amides to give amides and propanal can be achieved with PdII catalysts. The optimized catalyst consists of Pd(OCOCF3)2 and 1,3-bis(diphenylphosphanyl)propane (DPPP). Several kinds of open-chain N -allyl amides and N -allyl lactams undergo hydrolytic deallylation to give the corresponding amides and lactams in good to high yield. A mechanism which includes isomerization to enamides and subsequent hydrolysis is proposed. (© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2008) [source] Microstructures and adiabatic shear bands formed by ballistic impact in steels and tungsten alloyFATIGUE & FRACTURE OF ENGINEERING MATERIALS AND STRUCTURES, Issue 12 2003Z. Q. DUAN ABSTRACT Projectiles of sintered tungsten alloy were fired directly at two kinds of steel target plates. The microstructures near the perforation of a medium, 0.45% carbon steel target plate can be identified along the radial direction as: melted and rapidly solidified layer, recrystallized fine-grained layer, deformed fine-grained layer, deformed layer and normal matrix. The adiabatic shear bands cannot be found in this intermediate strength steel. The microstructures along the radial direction of perforation of 30CrMnMo steel target plate are different from that of the medium carbon steel. There was a melted and rapidly solidified layer on the surface of the perforation, underneath there was a diffusing layer, and then fine-grained layer appeared as streamlines. Several kinds of adiabatic shear bands were found in this higher strength steel; they had different directions and widths, which were relative to the shock waves, as well as the complex deformation process of penetration. The deformation of the projectiles was rather different when they impacted on target plates of medium carbon steel and 30CrMnMo steel. The projectile that impacted on the medium carbon steel target plate was tamped and its energy dissipated slowly, while that which impacted on the 30CrMnMo steel target plate was sheared and the energy dissipated quickly. [source] Creation of a Monomeric Ruthenium Species on the Surface of Micro-Size Copper Hydrogen Phosphate: An Active Heterogeneous Catalyst for Selective Aerobic Oxidation of AlcoholsADVANCED SYNTHESIS & CATALYSIS (PREVIOUSLY: JOURNAL FUER PRAKTISCHE CHEMIE), Issue 16 2007Junhua Liu Abstract A new micro-size copper hydrogen phosphate (CHP) synthesized by the emulsion method combined with a monomeric ruthenium species was found to be a very effective catalyst for the selective oxidation of alcohols. Several kinds of alcohols were transformed into the corresponding aldehydes or ketones over the RuCHP catalyst by oxygen under very mild conditions. The results showed that the CHP material was perfect as a catalyst support due to its high ion-exchange ability and adsorption capacity. [source] Bacterial population dynamics and community structure in a pharmaceutical manufacturing water supply system determined by real-time PCR and PCR-denaturing gradient gel electrophoresisJOURNAL OF APPLIED MICROBIOLOGY, Issue 6 2004M. Kawai Abstract Aims:, To control bacteria in the pharmaceutical water supply system. Methods and Results:, Bacteria were enumerated by conventional culture method and fluorescent vital staining. Activated carbon treatment and storage in a tank provided favourable environments for bacterial growth. The bacterial population of the water in both the post-activated carbon treatment and the tank was analysed by denaturing gradient gel electrophoresis (DGGE) with PCR-amplified 16S rDNA fragments including V6, -7, and -8 regions. The bacterial community structure in activated carbon treated water was stable throughout the year. Several kinds of bacteria such as genus Aquaspirillum and Methylobacterium were found in the water after activated carbon treatment. The bacterial community structure was changed and other bacteria such as mycobacteria were detected after storage. Mycobacteria were quantified in water samples using real-time PCR targeting the 16S rDNA gene. Mycobacteria were also detected in tap water and their number was increased 103,104 -fold higher after storage. Conclusion:, These data suggest the importance of culture-independent methods for quality control of water used in pharmaceutical manufacturing. Significance and Impact of the Study:, Critical steps and specified bacteria that should be controlled in the water supply system were recognized by culture-independent methods. These data will enable effective control of water used in the pharmaceutical industry. [source] Polymers with benzofuro-benzofuran structures,POLYMER INTERNATIONAL, Issue 10 2002Behzad Pourabas Abstract Several kinds of molecules and also polymers are going to be discussed in the present article. Common feature in these molecules and polymers is the possessing of a specific structural part, namely benzofuro,benzofuran. This structure will appear in several molecules and kinds of polymers in the text. A condensation reaction between glyoxal and phenols is the reaction needed to produce the mentioned structural part, ie benzofuro,benzofuran. Because of the importance of this reaction, a brief historical background in the initial section of the article, and some discussion on the structural assignment of the reaction product and the reaction mechanism is also given in sections later on. Types of polymers, which are discussed in this article, are mainly heat stable polymers including polyamide, poly(ether ketone sulfone), polybenzimidazole, poly(amide-benzimidazole) and polyarylates. Polyester, polyhaydrezide and polymers with NLO property are the other kinds of the discussed polymers in the text with the benzofuro,benzofuran structure in their main chain. There is not any detailed procedure provided in the text about the synthesis of the molecules or even the polymers and the general procedures provided follow only the methodological purposes of the authors. Thermal properties of the polymers are discussed in the final section of the article with an attempt to provide a comparative argument in order to reach a relationship between structure and thermal properties. © 2001 Society of Chemical Industry. [source] P44 A case of contact dermatitis caused by a NSAID's soluble agentCONTACT DERMATITIS, Issue 3 2004Yoshimi Kato A fifty five year-old man had experienced itching sensation when he applied analgesic plasters for his lumbago. He tried to use several kinds of analgesic plasters, however he felt itching sensation whenever he used them. He applied a plaster containing ferbinac for his left elbow joint's pain on April 2003. On the next day, an itching erythema developed on the area where the plaster was applied. He was treated with a difluprednate ointment, and his dermatitis gradually improved. He visited our clinic for precise medical examination for finding out the causative agent of his dermatitis on May 13, 2003. We conducted 48 hours closed patch testing with the plaster he used and it's ingredients. He reacted positively to the plaster containing ferbinac and crotamiton 5%p that was used for dissolute the active drug. He also reacted positively to a cream containing ketoprofen, however he reacted negatively to ketoprofen 1%p. Crotamoton was also used in the ketoprofen cream. [source] The roles of actin cytoskeleton and microtubules for membrane recycling of a food vacuole in Tetrahymena thermophilaCYTOSKELETON, Issue 7 2009Maki Sugita Abstract Phagocytosis is a fundamental cellular event for the uptake of nutrients from the environment in several kinds of eukaryote. Most ciliates egest waste and undigested materials in food vacuoles (FVs) through a cytoproct, which is a specific organelle for defecation. It is considered that FV egestion is initiated by fusion between the FV membrane and plasma membrane in a cytoproct and completed with retrieval of the membrane into a cytoplasmic space. In addition, electron microscopy indicated that microfilaments might be involved in the recycling process of the FV membrane in ciliates over 30 years ago; however, there is no conclusive evidence. Here we demonstrated actin organization on FV near a cytoproct in Tetrahymena thermophila by using a marker for a cytoproct. Moreover, it was revealed that cells treated with actin cytoskeletal inhibitor, Latrunculin B, might be suppressed for membrane retrieval in a cytoproct following FV egestion. On the other hand, the actin structures, likely to be the site of membrane retrieval, were frequently observed in the cells treated with cytoplasmic microtubules inhibitor, Nocodazole. We concluded that actin filaments were probably required for recycling of the FV membrane in a cytoproct although the role was not essential for FV egestion. In addition, it was possible that microtubules might be involved in transportation of recycling vesicles of FV coated with F-actin. Cell Motil. Cytoskeleton 2009. © 2009 Wiley-Liss, Inc. [source] Beliefs about worry in community-dwelling older adults,DEPRESSION AND ANXIETY, Issue 8 2006Ignacio Montorio Ph.D. Abstract This study examines the association between several kinds of beliefs about worry and generalized anxiety disorder (GAD) severity in a sample of older individuals recruited from a community setting (N=142, mean age=71.0 years, SD=6.0, range=55,88). Beliefs about worry were assessed with a 17-item scale designed for older adults, including three dimensions: Positive Beliefs, Negative Beliefs, and Responsibility. All three dimensions distinguished between people endorsing GAD symptoms and those without GAD symptoms, and only Negative Beliefs had a significant independent weight when regressed on GAD severity, even after controlling for level of trait worry. Results of this study suggest that negative beliefs appear to be strongly related to pathological worry in older adults. These results are consistent with empirical findings in younger adults and potentially support the use of particular interventions in clinical work with older adults with GAD. Depression and Anxiety 23:466,473, 2006. Published 2006 Wiley-Liss, Inc. [source] Learning to perceive object unity: a connectionist accountDEVELOPMENTAL SCIENCE, Issue 2 2002Denis Mareschal To explore questions of how human infants begin to perceive partly occluded objects, we devised two connectionist models of perceptual development. The models were endowed with an existing ability to detect several kinds of visual information that have been found important in infants' and adults' perception of object unity (motion, co-motion, common motion, relatability, parallelism, texture and T-junctions). They were then presented with stimuli consisting of either one or two objects and an occluding screen. The models' task was to determine whether the object or objects were joined when such a percept was ambiguous, after specified amounts of training with events in which a subset of possible visual information was provided. The model that was trained in an enriched environment achieved superior levels of performance and was able to generalize veridical percepts to a wide range of novel stimuli. Implications for perceptual development in humans, current theories of development and origins of knowledge are discussed. [source] The Evaluation Method of Smoothing Algorithms in VoltammetryELECTROANALYSIS, Issue 22 2003Malgorzata Jakubowska Abstract The criterion for testing the influence of smoothing algorithms for the relevant parameters considered in analytical experiment is presented. The proposed approach assumes that the improvement of the whole set of measured curves should be considered. The calibration curve parameters with confidence intervals, correlation coefficient, detection limit, signal to noise ratio and parameters of recovery function are utilized for the evaluation. Performance of evaluation method is presented for several kinds of experimental noises. [source] Supramolecular Assembly of Perylene Bisimide with , -Cyclodextrin Grafts as a Solid-State Fluorescence Sensor for Vapor DetectionADVANCED FUNCTIONAL MATERIALS, Issue 14 2009Yu Liu Abstract A nanoscopic supramolecular aggregate is constructed from perylene bisimide-bridged bis-(permethyl- , -cyclodextrins) 1 via ,,, stacking interactions. Its self-assembly behavior in organic and aqueous solutions is investigated by UV,Vis, fluorescence, and 1H NMR spectroscopy. Transmission electron microscopy and scanning electron microscopy images show the 1D nanorod aggregation of 1, which is birefringent under crossed polarizer conditions and strongly fluorescent as depicted in the fluorescence microscopy image. X-ray powder diffraction measurements indicate that 1 forms a well-ordered crystalline arrangement with a ,,, stacking distance of 4.02,Å. Furthermore, the solid-state fluorescence sensing is explored by utilizing the poly(vinylidene fluoride) membrane-embedded 1, giving that 1, as a novel vapor detecting material, can probe several kinds of volatile organic compounds and, especially, exhibits high sensitivity to organic amines. [source] Model,data synthesis in terrestrial carbon observation: methods, data requirements and data uncertainty specificationsGLOBAL CHANGE BIOLOGY, Issue 3 2005M. R. Raupach Systematic, operational, long-term observations of the terrestrial carbon cycle (including its interactions with water, energy and nutrient cycles and ecosystem dynamics) are important for the prediction and management of climate, water resources, food resources, biodiversity and desertification. To contribute to these goals, a terrestrial carbon observing system requires the synthesis of several kinds of observation into terrestrial biosphere models encompassing the coupled cycles of carbon, water, energy and nutrients. Relevant observations include atmospheric composition (concentrations of CO2 and other gases); remote sensing; flux and process measurements from intensive study sites; in situ vegetation and soil monitoring; weather, climate and hydrological data; and contemporary and historical data on land use, land use change and disturbance (grazing, harvest, clearing, fire). A review of model,data synthesis tools for terrestrial carbon observation identifies ,nonsequential' and ,sequential' approaches as major categories, differing according to whether data are treated all at once or sequentially. The structure underlying both approaches is reviewed, highlighting several basic commonalities in formalism and data requirements. An essential commonality is that for all model,data synthesis problems, both nonsequential and sequential, data uncertainties are as important as data values themselves and have a comparable role in determining the outcome. Given the importance of data uncertainties, there is an urgent need for soundly based uncertainty characterizations for the main kinds of data used in terrestrial carbon observation. The first requirement is a specification of the main properties of the error covariance matrix. As a step towards this goal, semi-quantitative estimates are made of the main properties of the error covariance matrix for four kinds of data essential for terrestrial carbon observation: remote sensing of land surface properties, atmospheric composition measurements, direct flux measurements, and measurements of carbon stores. [source] New supplying evaporation precursor method with CVDHEAT TRANSFER - ASIAN RESEARCH (FORMERLY HEAT TRANSFER-JAPANESE RESEARCH), Issue 5 2009Motohiro Oshima Abstract We propose a novel system of chemical vapor deposition (CVD), i.e., flash boiling spray CVD (SF-CVD) to eliminate several kinds of problems, such as the decomposition of precursors in the supply line and evaporator. In this method, liquid precursors are supplied directly to the vacuum chamber through an injector, just like fuel for an automobile engine, without any vaporizers, so as to induce an unsteady and intermittent flash boiling spray in the chamber. However, it is necessary to keep the lowest ambient pressure possible because the saturated vapor pressure of the precursors is very low. Thus, this is very useful for modifying the saturated vapor pressure of the precursors. A technique of lowering the vaporization pressure is proposed by mixing a more saturated vapor-pressure organic solvent with a precursor. To determine the principles underlying FS-CVD, we first formed SiO2 film on the Si substrate. A mixed solution of tetraethylorthosilicate (TEOS) and n-pentane was used as the mixing solution. The film thickness distribution of SiO2 film on a 100-mm-diameter Si wafer was ±4% using this method. Furthermore, this method enabled us to control film with various thicknesses by optimizing the injection duration, cycle, and injection cycle per second. © 2009 Wiley Periodicals, Inc. Heat Trans Asian Res; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/htj.20235 [source] Overlay for Membrane-Bound Protein Biochips:IMAGING & MICROSCOPY (ELECTRONIC), Issue 4 2009A Combined Optical Microscopy, AFM Study Phospholipids bilayer membrane represents a fundamental element within the cell, protecting the inner cell from the outside while enabling the communication of the cell with its environment. Composed of several kinds of phospholipids, mixed at defined ratio, it presents also numerous proteins assembly as for example chemotaxis receptors, or larger structure such as the bacterial flagellar Nano-Motor [1]. Despite its importance, studying phospholipids membrane in native environment remains challenging due to numerous technical limitations. [source] Discrete element modelling of deep penetration in granular soilsINTERNATIONAL JOURNAL FOR NUMERICAL AND ANALYTICAL METHODS IN GEOMECHANICS, Issue 4 2006M. J. Jiang Abstract This paper presents a numerical study on deep penetration mechanisms in granular materials with the focus on the effect of soil,penetrometer interface friction. A two-dimensional discrete element method has been used to carry out simulation of deep penetration tests on a granular ground that is under an amplified gravity with a K0 lateral stress boundary. The numerical results show that the deep penetration makes the soil near the penetrometer move in a complex displacement path, undergo an evident loading and unloading process, and a rotation of principal stresses as large as 180°. In addition, the penetration leads to significant changes in displacement and velocity fields as well as the magnitude and direction of stresses. In general, during the whole penetration process, the granular ground undergoes several kinds of failure mechanisms in sequence, and the soil of large deformation may reach a stress state slightly over the strength envelope obtained from conventional compression tests. Soil,penetrometer interface friction has clear effects on the actual penetration mechanisms. Copyright © 2005 John Wiley & Sons, Ltd. [source] Tumour-associated macrophages and melanoma tumourigenesis: integrating the complexityINTERNATIONAL JOURNAL OF EXPERIMENTAL PATHOLOGY, Issue 3 2006Mahmoud R. Hussein Summary When the body discovers a tumour cell (foreign antigen), several kinds of mechanisms and cells operate in what is called an immune response. The latter has evolved into two mechanisms: non-specific immunity and specific immunity, which are closely linked to and influence each other. The former represents the first line of defence against neoplastic cells. The adaptive (specific) immunity is orchestrated by antigen-specific T and B lymphocytes. The effector cells of innate immunity include granulocytes, macrophages and natural killer cells. Among these cells, macrophages represent the most important part of innate immunity against tumours. Tumour-associated macrophages (TAMs) are important antigen-presenting cells and as such an understanding of their interactions with tumour cells gives insights into novel therapeutic strategies. In tumours, the effect of TAMs is the outcome of their two concomitantly competing interactions: tumour growth reduction and tumour growth promotion. The macrophage (TAMs) content of melanoma ranges from 0 to 30% and their density increases with increasing tumour thickness. The melanoma cells and TAMs seem to interact with each other through the release of soluble factors that either prevent or enhance tumour growth. For instance, syngeneic macrophages from tumour-bearing mice can inhibit melanoma growth in the nude mice more than the control macrophages. Alternatively, metastatic B16 melanoma cells can produce some macrophage cytotoxic substances that help tumour cells not only escape the host immunosurveillance system but also prevent distant metastasis. Together, these observations suggest opposing effects for these soluble factors in melanoma. To date, little is available in the literature about the interactions between TAMs and melanoma cells. This viewpoint not only tries to examine these interactions but also provides relevant speculations. [source] How Should Clinicians Describe Hospice to Patients and Families?JOURNAL OF AMERICAN GERIATRICS SOCIETY, Issue 11 2004David J. Casarett MD Objectives: To describe hospice enrollment from the perspective of bereaved family members and to identify information about hospice that would encourage patients and families to enroll sooner. Design: Cross-sectional interviews. Setting: Three Medicare-certified hospice organizations. Participants: One hundred family members of 100 patients who died in hospice. Measurements: Semistructured interviews assessed prior knowledge of hospice, patients' and physicians' involvement in the enrollment process, features of hospice that motivated enrollment, and features that patients and families wished they had learned about sooner. Results: Almost all family members (n=92) and patients (n=71) knew about hospice before the patient's illness. Almost half the patients (n=44) were not involved at all in the hospice enrollment decision. The patient's physician (n=51) or the patient or family (n=34) initiated most hospice discussions, but patients and families usually obtained information about hospice from a hospice representative (n=75) rather than from the patient's physician (n=22). Family members identified several kinds of information about hospice that were particularly helpful in deciding whether to enroll and described several aspects of hospice that they wished they had known about sooner. Conclusion: Many patients and families learn about hospice from someone other than the patient's physician, and most learn about valuable hospice features and services only after enrollment. By providing more information about hospice earlier in the illness course, clinicians may be able to facilitate more-informed and more-timely decisions about hospice enrollment. [source] Complications associated with enteral nutrition by nasogastric tube in an internal medicine unitJOURNAL OF CLINICAL NURSING, Issue 4 2001Pedro L. Pancorbo-Hidalgo PhD ,,Enteral nutrition through a nasogastric tube is a technique often used with hospitalized patients when they present problems with oral nutrition. ,,Patients receiving enteral nutrition show several kinds of complications such as diarrhoea, vomiting, constipation, lung aspiration, tube dislodgement, tube clogging, hyperglycaemia and electrolytic alterations. ,,We present a prospective and observational study carried out in an Internal Medicine Unit with 64 patients who were fed by a nasogastric tube. From the results it can be seen that older people represented a majority (the average age was 76.2 years), and difficulty in swallowing was the main reason for beginning enteral nutrition. ,,The complications which appeared were: tube dislodgement (48.5%); electrolytic alterations (45.5%); hyperglycaemia (34.5%); diarrhoea (32.8%); constipation (29.7%); vomiting (20.4%); tube clogging (12.5%); and lung aspiration (3.1%). We discuss the possible relationship between the different factors associated with the enteral nutrition procedure and the occurrence of these complications. ,,Finally, some nursing interventions are suggested, such as: checking the gastric residue periodically; attempting to place the tube in the duodenum in unconscious patients; and the use of protective mittens in disturbed patients. [source] Amino acids outside of the loops that define the agonist binding site are important for ligand binding to insect nicotinic acetylcholine receptorsJOURNAL OF NEUROCHEMISTRY, Issue 1 2008Zewen Liu Abstract Nicotinic acetylcholine (ACh) receptors (nAChRs) are the targets of several kinds of insecticides. Based on the mutagenesis studies of Torpedo californica nAChRs and solved structure of a molluscan, glial-derived soluble ACh-binding protein, a model of the agonist site was constructed with contributing amino acids from three distinct loops (A, B, and C) of the , subunits and another three loops (D, E, and F) of the non-, subunits. According to this model, most insect nAChR subunits can form the functional heteromeric or homomeric receptors. Actually, insect subunits themselves did not form any functional receptor at various combinations as yet, and only part of them can form the functional receptors with vertebrate non-, subunits. These findings suggested that the agonist binding for insect nAChRs was not only contributed by those key amino acids in six loops, but also some unidentified amino acids from other regions. In our previous studies on nAChRs for Nilaparvata lugens, a target-site mutation (Y151S) was found within two , subunits (Nl,1 and Nl,3). In Drosophila S2 cells and Xenopus oocytes, Nl,1 can form functional receptors with rat ,2 subunit. However, the same thing was not observed in Nl,3. In the present paper, by exchanging the corresponding regions between Nl,1 and Nl,3 to generate different chimeras, amino acid residues or residue clusters in the regions outside the six loops were found to play essential roles in agonist binding, especially for the amino acid clusters between loop B and C. This result indicated that the residues in the six loops could be necessary, but not enough for the activity of agonist binding. [source] Quantification of suppression of bitterness using an electronic tongueJOURNAL OF PHARMACEUTICAL SCIENCES, Issue 12 2001Sou Takagi Abstract Phospholipids, such as phosphatidic acid, suppress bitter taste without affecting other taste qualities. In the present study, we detected and quantified this suppression effect with an electronic tongue whose transducer is composed of several kinds of lipid/polymer membranes with different characteristics. We measured a phospholipid cocktail and various kinds of taste substances with five basic taste qualities. The responses to quinine hydrochloride and L -tryptophan, which have a bitter taste, were reduced as the phospholipid concentration was increased, and the responses to the other taste substances were not affected by the phospholipids, as with the human sensation test. Furthermore, the change of bitter interisity caused by phospholipid was quantified by principal component analysis and the , scale, which expresses the relationship between taste intensity and taste substance concentration. The results are compared with those of the human sensory test and discussed. © 2001 Wiley-Liss, Inc. and the American Pharmaceutical Association J Pharm Sci 90:2042,2048, 2001 [source] Relevance: A review of the literature and a framework for thinking on the notion in information science.JOURNAL OF THE AMERICAN SOCIETY FOR INFORMATION SCIENCE AND TECHNOLOGY, Issue 13 2007Part II: nature, manifestations of relevance Relevant: Having significant and demonstrable bearing on the matter at hand., Relevance: The ability as of an information retrieval system to retrieve material that satisfies the needs of the user. ,Merriam-Webster Dictionary 2005 Relevance is a, if not even the, key notion in information science in general and information retrieval in particular. This two-part critical review traces and synthesizes the scholarship on relevance over the past 30 years and provides an updated framework within which the still widely dissonant ideas and works about relevance might be interpreted and related. It is a continuation and update of a similar review that appeared in 1975 under the same title, considered here as being Part I. The present review is organized into two parts: Part II addresses the questions related to nature and manifestations of relevance, and Part III addresses questions related to relevance behavior and effects. In Part II, the nature of relevance is discussed in terms of meaning ascribed to relevance, theories used or proposed, and models that have been developed. The manifestations of relevance are classified as to several kinds of relevance that form an interdependent system of relevances. In Part III, relevance behavior and effects are synthesized using experimental and observational works that incorporate data. In both parts, each section concludes with a summary that in effect provides an interpretation and synthesis of contemporary thinking on the topic treated or suggests hypotheses for future research. Analyses of some of the major trends that shape relevance work are offered in conclusions. [source] Electrically Conductive Poly(DL -lactide)/Chitosan/Polypyrrole ComplexesMACROMOLECULAR RAPID COMMUNICATIONS, Issue 12 2006Ying Wan Abstract Summary: The fabrication of novel conductive poly(DL -lactide)/chitosan/polypyrrole complex membranes is reported. Using poly(DL -lactide)/chitosan blends as matrices and polypyrrole as a conductive component, several kinds of membranes with various compositions are prepared. A percolation threshold of polypyrrole as low as 1.8 wt.-% is achieved for some membranes by controlling the chitosan proportion between 40 and 50 wt.-%. SEM images exhibit that the membranes with a low percolation threshold show a two-phase structure which consists of poly(DL -lactide) and chitosan phases. Dielectric measurements indicate that there is limited miscibility between the poly(DL -lactide) and chitosan but polypyrrole is nearly immiscible with the other two components. Based on the structural characteristics of the membranes, the polypyrrole particles are suggested to be localized at the interface between two phases. Dependence of conductivity of complex membranes on the PPy content. (,) PDLLA/PPy, (,) PDLLA/ch(10)/PPy, (,) PDLLA/ch(20)/PPy, (,) PDLLA/ch(30)/PPy, (,) PDLLA/ch(40)/PPy, and (,) PDLLA/ch(50)-PPy. [source] The GRB early optical flashes from internal shocks: application to GRB 990123, GRB 041219a and GRB 060111bMONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY, Issue 2 2007D. M. Wei ABSTRACT With the successful launch of the Swift Gamma-ray Burst Explorer, it is widely expected that the prompt optical flashes like GRB 990123 would be easily detected. However, the observations show that for a number of Gamma-ray bursts (GRBs) no early optical flash has been detected, which indicates that the reverse shock emission must be suppressed. Here we explore the possibility that the optical flash may arise from the internal shock emission. For GRB 990123 and GRB 060111b, although their optical emission are not correlated with the gamma-ray emission, we propose here that their optical and gamma-ray emission may arise from different internal shocks (which can be formed by collision of different shells), and find that, under certain circumstances, the optical flashes of GRB 990123 and GRB 060111b can well be explained by the internal shock model. For GRB 041219a, the prompt optical emission was correlated with the gamma-ray emission, which can also be explained by the internal shock model if we assume the optical emission was the low-energy extension of the gamma-ray emission, and we find its redshift is about z, 0.2. As for GRB 050904, we have shown in previous paper that the optical flash was produced by synchrotron radiation and the X-ray flare was produced by the synchrotron,self-Compton (SSC) mechanism. Therefore we conclude that the early optical flashes of GRBs can usually arise from the internal shock emission. Meanwhile in our model since the shells producing the optical flashes would be easily disrupted by other shells, so we suggest that the bright optical flash should not be common in GRBs. In addition, we also discussed the SSC emission in the internal shock model, and find that for different values of parameters, there would be several kinds of high-energy emission (at ,100 keV, ,10 MeV or GeV) accompanying the optical flash. For a burst like GRB 990123, a GeV flare with fluence about 10,8 erg cm,2 s,1 is expected, which might be detected by the GLAST satellite. [source] Effects of ultraviolet radiation and temperature on the ultrastructure of zoospores of the brown macroalga Laminaria hyperboreaPLANT BIOLOGY, Issue 3 2008F. S. Steinhoff Abstract The interactive effects of an 8 h exposure to UV radiation and altered temperatures on the ultrastructure and germination of zoospores of the sublittoral brown alga Laminaria hyperborea (Gunn.) Foslie were investigated for the first time. Spores were exposed to four temperatures (2, 7, 12 and 17 °C) and three light regimes (PAR, PAR + UV-A, PAR + UV-A+UV-B). Freshly-released spores of L. hyperborea lack a cell wall and contain a nucleus with fine granular nucleoplasm and a nucleolus, one chloroplast, several mitochondria, dictyosomes and an endoplasmatic reticulum. Further, several kinds of so-called adhesive vesicles, lipid globuli and physodes containing UV-absorbing phlorotannins are embedded in the cytoplasm. No eye-spot is present. Physodes were found but they were rare and small. After an 8 h exposure to UV-B, the nucleoplasm had a mottled structure, chloroplasts contained plastoglobuli, the structure of the mitochondria changed from crista- to sacculus-type and germination was strongly inhibited at all temperatures. UV-A only had an impact on the ultrastructure at the highest temperature tested. The strongest effects were found at 17 °C, where germination was reduced to 35%, 32% and 9% after exposure to PAR, PAR+UV-A and PAR + UV-A + UV-B, respectively. This study indicates that UV-B radiation has strong damaging effects on the physiology and ultrastructure of zoospores of L. hyperborea. The results are important for developing scenarios for the effect of enhanced UV radiation and increasing temperatures caused by global climate changes. [source] Global Model of He/O2 and Ar/O2 Atmospheric Pressure Glow DischargesPLASMA PROCESSES AND POLYMERS, Issue 6 2008Ganyoung Park Abstract Atmospheric pressure glow discharges (APGDs) have widespread applications, including sterilization, cancer cell treatment, deposition, and surface modification due to their rather simple configurations, thanks to no need for vacuum system and their great capability to generate reactive species such as radical oxygen species. Helium and argon are widely used as feeding gases, achieving stable operations for wide ranges of parameters in atmospheric pressure, and oxygen is added into these gases to generate more reactive oxygen species (ROS), which play a significant role in sterilization. As the measurements of species densities and electron temperature in APGDs are difficult, we have developed the zero-dimensional global model of He/O2 and Ar/O2 APGDs to calculate the densities of several kinds of species and electron temperature. It was shown that even though small fraction of oxygen less than 1% was added to helium or argon, electrons dissipated most of their energy through collisions with oxygen molecules rather than helium or argon atoms. The densities of electron, atomic oxygen, and ozone of Ar/O2 were higher than those of He/O2; however, the electron temperature of He/O2 was higher than that of Ar/O2. When the pulsed power is applied, the time-averaged electron temperature for the shorter pulse period and the larger duty ratio increased, and the electron density decreased as the duty ratio increased. [source] 3-D non-isothermal flow field analysis and mixing performance evaluation of kneading blocks in a co-rotating twin srew extruderPOLYMER ENGINEERING & SCIENCE, Issue 5 2001Takeshi Ishikawa We have developed a three-dimensional non-Newtonian and non-isothermal flow analysis of the twin screw extruder (TSE) using the finite element method. This code can simulate the fully filled parts of several kinds of screw elements, such as full flight screws, kneading blocks, rotors and their combinations. A marker particle tracking analysis has also been developed to evaluate the mixing performance of the screw elements. In this paper, simulations for the kneading blocks in a co-rotating TSE were carried out. The screw configurations are combinations of 2-lobe kneading blocks with several stagger angles and disk widths. The effects of screw configurations on pressure and temperature distributions are examined. We also evaluate the dispersive and distributive mixing via stress magnitude and area stretch obtained by marker particle tracking analysis. Additionally, we discuss the desirable stagger, disk width and their combinations that promote the mixing performance. [source] Determination of the human type I interferon receptor binding site on human interferon-,2 by cross saturation and an NMR-based model of the complexPROTEIN SCIENCE, Issue 11 2006Sabine R. Quadt-Akabayov Abstract Type I interferons (IFNs) are a family of homologous helical cytokines that exhibit pleiotropic effects on a wide variety of cell types, including antiviral activity and antibacterial, antiprozoal, immunomodulatory, and cell growth regulatory functions. Consequently, IFNs are the human proteins most widely used in the treatment of several kinds of cancer, hepatitis C, and multiple sclerosis. All type I IFNs bind to a cell surface receptor consisting of two subunits, IFNAR1 and IFNAR2, associating upon binding of interferon. The structure of the extracellular domain of IFNAR2 (R2-EC) was solved recently. Here we study the complex and the binding interface of IFN,2 with R2-EC using multidimensional NMR techniques. NMR shows that IFN,2 does not undergo significant structural changes upon binding to its receptor, suggesting a lock-and-key mechanism for binding. Cross saturation experiments were used to determine the receptor binding site upon IFN,2. The NMR data and previously published mutagenesis data were used to derive a docking model of the complex with an RMSD of 1 Å, and its well-defined orientation between IFN,2 and R2-EC and the structural quality greatly improve upon previously suggested models. The relative ligand,receptor orientation is believed to be important for interferon signaling and possibly one of the parameters that distinguish the different IFN I subtypes. This structural information provides important insight into interferon signaling processes and may allow improvement in the development of therapeutically used IFNs and IFN-like molecules. [source] Biology of the prolactin family in bovine placenta.ANIMAL SCIENCE JOURNAL, Issue 1 2006ABSTRACT Bovine placenta produces an array of proteins that are structurally and functionally similar to pituitary prolactin. Bovine placental lactogen (bPL) is a glycoprotein hormone that has lactogenic and somatogenic properties. Purified bPL contains several kinds of isoforms that are created by alternative splicing and/or multiple glycosylation patterns. bPL can activate the prolactin (PRL) receptor-mediated signaling pathway as well as PRL does. The bPL mRNA is transcribed in trophoblast binucleate cells, and synthesized bPL protein is stored in membrane-bound secretory granules. The message encoding bPL is first detectable in trophoblast binucleate cells at approximately day 20 of gestation at, or shortly after, the appearance of binucleate cells in the trophoblast. Most binucleate cells are detected as expressed bPL in the placenta. Bovine PL may be the determinant in trophoblast differentiation. Although the biological activities of bPL have long been studied, the precise role of bPL is still largely unclear. This article reviews and discusses the biological roles of bPL, focusing on luteal function, fetal growth and pregnancy-associated maternal adaptation, mammogenesis and lactogenesis, and placental angiogenesis. The precise biological function of bPL needs to be further evaluated. [source] Toward a Pluralist Account of ParenthoodBIOETHICS, Issue 3 2003Tim Bayne What is it that makes someone a parent? Many writers , call them ,monists', claim that parenthood is grounded solely in one essential feature that is both necessary and sufficient for someone's being a parent. We reject not only monism but also ,necessity' views, in which some specific feature is necessary but not also sufficient for parenthood. Our argument supports what we call ,pluralism', the view that any one of several kinds of relationship is sufficient for parenthood. We begin by challenging monistic versions of gestationalism, the view that gestation uniquely grounds parenthood. Monistic and necessity gestationalism are implausible. First, we raise the ,paternity problem', necessity gestationalists lack an adequate account of how men become fathers. Second, the positive arguments that necessity gestationalists give are not compelling. However, although gestation may not be a necessary condition for parenthood, there is good reason to think that it is sufficient. After further rebutting an ,intentionalist' account of parenthood, in which having and acting on intentions to procreate and rear is necessary for parenthood, we end by sketching a pluralist picture of the nature of parenthood, rooted in causation, on which gestation, direct genetic derivation, extended custody, and even, sometimes, intentions, may be individually sufficient for parenthood. [source] | |||||||||||||||||||||||||