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Demonstration
Kinds of Demonstration Terms modified by Demonstration Selected AbstractsESTIMATION OF THE NUMBER OF PEOPLE IN A DEMONSTRATIONAUSTRALIAN & NEW ZEALAND JOURNAL OF STATISTICS, Issue 1 2010Paul S. F. Yip Summary It is of interest to estimate the size of a crowd in a demonstration. We propose a practical method to obtain an estimate of the size of the crowd and its standard error. This method has been implemented in practice and, compared with other counting methods, is found to be more efficient, more timely and have less scope for bias. The method described in this paper was motivated by the annual 1 July demonstrations in Hong Kong, and data from the 2006 demonstration are used as an example of the proposed method. [source] The Sandwich Factory: An In-Class Demonstration of Pull Production ConceptsDECISION SCIENCES JOURNAL OF INNOVATIVE EDUCATION, Issue 1 2009Timothy S. Vaughan First page of article [source] Stochastic models for simulation of strong ground motion in IcelandEARTHQUAKE ENGINEERING AND STRUCTURAL DYNAMICS, Issue 9 2001Símon Ólafsson Abstract Two types of modelling approaches for simulating ground motion in Iceland are studied and compared. The first type of models, named discrete-time series models (ARMA), are based solely on measured acceleration in earthquakes occurring in Iceland. The second type of models are based on a theoretical seismic source model called the extended Brune model. Based on measured acceleration in Iceland during the period 1986,1996, the parameters for the extended Brune models have been estimated. The seismic source models are presented here as ARMA models, which simplifies the simulation process. A single-layer soil amplification model is used in conjunction with the extended Brune model to estimate local site amplification. Emphasis is put on the ground motion models representing the variability in the measured earthquakes, with respect to energy, duration and frequency content. Demonstration is made using these models for constructing linear and non-linear probabilistic response spectra using a discretised version of the Bouc,Wen model for the hysteresis of the second-order system. Copyright © 2001 John Wiley & Sons, Ltd. [source] Demonstration of Left Ventricular Outflow Tract Eccentricity by Real Time 3D Echocardiography: Implications for the Determination of Aortic Valve AreaECHOCARDIOGRAPHY, Issue 8 2007Sanjay Doddamani M.D. Background: Determination of the left ventricular outflow tract cross-sectional area (ALVOT) is necessary for calculating aortic valve area (AVA) by echocardiography using the continuity equation (CE). In the commonly applied form of CE, ,r2 is used to estimate ALVOT utilizing the assumptions that LVOT is round and the parasternal long axis (PLAX) plane bisects LVOT. Imaging LVOT using real time 3D echocardiography (RT3DE) eliminates the need for these assumptions. We tested the hypothesis that LVOT is round based on a formula for eccentricity. Methods and Results: In 53 patients, 2D echocardiography (2DE) and RT3DE were acquired. ALVOT was calculated by 2DE using ,r2 (ALVOT-2D). Using RT3DE, ALVOT planimetry was performed immediately beneath the aortic valve (ALVOT-3Dplan). Eccentricity Index (EI) was calculated using the shortest and longest LVOT diameters. The long axis was measured to be larger by 0.53 cm ± 0.36 (P < 0.005). The median EI was 0.20 (0.00,0.54), indicating that half the subjects had at least a 20% difference between the major and minor diameters. ALVOT-3Dplan was larger than ALVOT-2D (3.73 ± 0.95 cm2 vs. 3.18 ± 0.73 cm2; P < 0.001) by paired analysis. Using the equation of an ellipse (,ab), ALVOT-3Dellip was 3.57 ± 0.95 resulting in improved agreement with ALVOT-3Dplan. Conclusions: In our small patient sample with normal aortic valves, we showed the LVOT shape is usually not round and frequently, elliptical. Incorrectly assuming a round LVOT underestimated the ALVOT-3Dplan and consequently the AVA by 15%. Investigating the LVOT in aortic stenosis is warranted to evaluate whether RT3DE may improve measurement of AVA. [source] Transesophageal and Transpharyngeal Ultrasound Demonstration of Reversed Diastolic Flow in Aortic Arch Branches and Neck Vessels in Severe Aortic RegurgitationECHOCARDIOGRAPHY, Issue 4 2004Deepak Khanna M.D. In the current study, we describe an adult patient with torrential aortic regurgitation due to an aortic dissection flap interfering with aortic cusp motion, in whom a transesophageal echocardiogram with the probe positioned in the upper esophagus and transpharyngeal ultrasound examination demonstrated prominent reversed flow throughout diastole in the left subclavian, left vertebral, left common carotid, and left internal carotid arteries. Another unique finding was the demonstration of aortic valve leaflets held in the fully opened position in diastole by the dissection flap as it prolapsed into the left ventricular outflow tract, dramatically documenting the mechanism of torrential aortic regurgitation in this patient. (ECHOCARDIOGRAPHY, Volume 21, May 2004) [source] Three-Dimensional Transesophageal Echocardiographic Demonstration of Intraatrial Baffle ObstructionECHOCARDIOGRAPHY, Issue 5 2003Sujood Ahmed We report an adult patient with transposition of the great arteries status post-Mustard procedure in whom three-dimensional transesophageal echocardiography demonstrated intraatrial baffle obstruction. The baffle could be visualized in both long-axis and "en face" short-axis views. (ECHOCARDIOGRAPHY, Volume 20, July 2003) [source] The Electrochemical Oxidation of 5-Thio-2-nitrobenzoic acid (TNBA) at a Boron Doped Diamond Electrode: Demonstration of a CEC ReactionELECTROANALYSIS, Issue 19 2003Olga Nekrassova Abstract The oxidation of 5-thio-2-nitrobenzoic acid (TNBA) over a wide pH range has been investigated using cyclic voltammetry at a boron doped diamond electrode. The reaction has been shown to proceed via a CEC reaction process in which at lower pH the thiol moiety of the TNBA species has to undergo deprotonation before oxidation. DIGISIM modelling of the voltammetric profiles deduced a value of 5.2 for the pKa of the thiol moiety which is in good agreement with that obtained from spectrophotometric data. Also reported are the rate constants for all the heterogeneous and homogeneous processes. [source] Cytochrome P4501A induction potencies of polycyclic aromatic hydrocarbons in a fish hepatoma cell line: Demonstration of additive interactionsENVIRONMENTAL TOXICOLOGY & CHEMISTRY, Issue 8 2000Karl Fent Abstract The relative CYP1A induction potencies, determined as ethoxyresorufin- O -deethylase (EROD) activity, and the cytotoxicities of 19 compounds with one to six benzene rings, mixtures of polycyclic aromatic hydrocarbons (PAHs), and contaminated landfill leachates have been determined in the permanent fish hepatoma cell line PLHC-1. No CYP1A induction was observed with benzene, naphthalene, anthracene, acenaphthene, benzo[g,h,i]perylene, and fluorene and low induction was found with fluoranthene and phenanthrene. All other PAHs with three and more benzene rings led to a concentration-related induction of CYP1A, with rebound decreases at high concentrations resulting in bell-shaped concentration,activity curves. Fish-related induction equivalency factors (IEFs) were estimated for all PAHs on the basis of EC50 values of their EROD activities and are reported here for the first time. The following order of decreasing IEFs was found: dibenz[a,h]anthracene > dibenzo[a,i]pyrene > benzo[k]fluoranthene > 3-methylcholanthrene > benzo[a]pyrene > benzo[e]pyrene > chrysene > 7,12-dimethylbenz[a]anthracene > perylene > benz[a]anthracene > pyrene. In contrast to the EROD activity, the immunodetectable protein content determined by ELISA showed a concentration-dependent increase. The interaction of PAHs in mixtures of up to eight individual compounds was additive based on their EROD activities. In landfill leachates, determined induction equivalents (IEQ) were significantly higher than calculated IEQs based on analytical measurements, which indicates additional unknown inducing compounds present in leachates. This study shows that the PLHC-1 cell in vitro system serves as an integrative bioanalytical tool in the ecotoxicological evaluation of aquatic environmental samples contaminated with CYP1A-inducing compounds. [source] Demonstration of strong enterobacterial reactivity of CD4+CD25, T,cells from conventional and germ-free mice which is counter-regulated by CD4+CD25+ T,cellsEUROPEAN JOURNAL OF IMMUNOLOGY, Issue 3 2004Monika Gad Abstract Unfractionated CD4+ T,cells from the gut-associated lymphoid tissue (GALT) and peripheral lymph nodes are unresponsive when exposed to enterobacterial antigens in vitro. Under similar conditions, CD4+ T,cells depleted in vivo or in vitro of CD4+CD25+ T,cells proliferate extensively. The CD4+CD25, T,cell reactivity depends on MHC class,II presentation, specific TCR stimulation, CD4 ligation, and antigen processing by antigen-presenting cells. The CD4+CD25, T,cells respond to autologousand heterologous enterobacterial antigens, but not to antigens from the feces of germ-free mice. Surprisingly, CD4+CD25, T,cells obtained from the GALT of germ-free mice also proliferate when exposed to enterobacterial antigens, and adding back the conventional or germ-free CD4+CD25+ T,cells to the enteroantigen-stimulated CD4+CD25, T,cells abolishes proliferation. As judged from carboxyfluorescein diacetate succinimidyl ester-labeling experiments, 4,5% of the CD4+CD25, T,cells respond to enteroantigen. The data show for the first time that CD4+CD25, T,cells with reactivity towards the enterobacterial flora and regulatory CD4+CD25+ T,cells are present in both conventional and germ-free mice. The data suggest that a significant proportion of the peripheral pool of CD4+CD25, T,cells express anti-enterobacterial reactivity, which, due to the presence of regulatory CD4+CD25+ T,cells, is kept in a quiescent state. [source] Demonstration of long-range GABAergic connections distributed throughout the mouse neocortexEUROPEAN JOURNAL OF NEUROSCIENCE, Issue 6 2005Ryohei Tomioka Abstract ,-Aminobutyric acid (GABA)ergic neurons in the neocortex have been mainly regarded as interneurons and thought to provide local interactions. Recently, however, glutamate decarboxylase (GAD) immunocytochemistry combined with retrograde labeling experiments revealed the existence of GABAergic projection neurons in the neocortex. We further studied the network of GABAergic projection neurons in the neocortex by using GAD67-green fluorescent protein (GFP) knock-in mice for retrograde labeling and a novel neocortical GABAergic neuron labeling method for axon tracing. Many GFP-positive neurons were retrogradely labeled after Fast Blue injection into the primary somatosensory, motor and visual cortices. These neurons were labeled not only around the injection site, but also at a long distance from the injection site. Of the retrogradely labeled GABAergic neurons remote from the injection sites, the vast majority (91%) exhibited somatostatin immunoreactivity, and were preferentially distributed in layer II, layer VI and in the white matter. In addition, most of GABAergic projection neurons were positive for neuropeptide Y (82%) and neuronal nitric oxide synthase (71%). We confirmed the long-range projections by tracing GFP-labeled GABAergic neurons with axon branches traveled rostro-caudally and medio-laterally. Axon branches could be traced up to 2 mm. Some (n = 2 of 4) were shown to cross the areal boundaries. The GABAergic projection neurons preferentially received neocortical inputs. From these results, we conclude that GABAergic projection neurons are distributed throughout the neocortex and are part of a corticocortical network. [source] Visible-Light Photoresponsivity of a 4-(Dimethylamino)azobenzene Unit Incorporated into Single-Stranded DNA: Demonstration of a Large Spectral Change Accompanying Isomerization in DMSO and Detection of Rapid (Z)-to-(E) Isomerization in Aqueous SolutionEUROPEAN JOURNAL OF ORGANIC CHEMISTRY, Issue 11 2007Takashi Kamei Abstract We demonstrate significant visible-light photoresponsivity in a synthesized oligonucleotide containing a built-in pseudo-nucleotide possessing a 4-(dimethylamino)azobenzene (4-DMAzo) side chain. In dry DMSO as solvent, two clearly distinguishable spectra corresponding to the (E) and (Z) forms of the 4-DMAzo moiety tethered to the oligonucleotide were recorded with a conventional spectrophotometer before and after irradiation with 420 nm wavelength light, which induced (E)-to-(Z) isomerization. In addition, (Z)-to-(E) isomerization was accelerated by irradiation with either visible (, = 550 nm) or UV (, = 350 nm) light, demonstrating reversible photoresponsivity of the pseudo-oligonucleotide. In aqueous solutions the (Z)-to-(E) thermal isomerization of the photoresponsive pseudo-oligonucleotide was very rapid and was only detectable by laser flash photolysis.(© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2007) [source] Oral health conditions of community-dwelling cognitively intact elderly persons with disabilitiesGERODONTOLOGY, Issue 2 2007Ralph Saunders Objectives:, To present descriptive information on oral health and health care of community-dwelling elderly persons with disabilities who are living at home. Background:, Most previous studies have focused on specific subpopulations, namely, persons who are essentially healthy and independent, are homebound, or are nursing home residents. Little information appears to be available on community-residing elderly persons with disabilities. Materials and methods:, A total of 641 participants aged 65 years and over in a Medicare Demonstration who were cognitively intact, completed an oral health questionnaire within 1 year of Demonstration entry. Demonstration participants were required to be living in the community, need or receive help with 2+ activities of daily living (ADLs) or 3+ instrumental ADLs (IADLs), and have recently experienced significant health services utilisation. Results:, Subject mean age was 79.1 years, 73.8% were female, and 4% were minority. They were dependent in a mean of 1.8 ADLs and 2.9 IADLs. 43.1% reported that they had no natural teeth, 77.4% had dentures, 58.8% frequently felt their mouth was dry, 5.2% had jaw pain now and 6.1% had at some time experienced burning sensations in their mouth or tongue. 40.4% reported that they were currently in need of dental treatment, although 56.2% indicated they now had a dentist, and 42.1% identified having a dental visit within the past 12 months. 19.7% indicated some dental insurance coverage. Conclusion:, This is one of the first studies to focus on community-dwelling elderly people with disabilities. Substantial oral health morbidity was reported. [source] The Public/Private Partnership behind the Cash and Counseling Demonstration and Evaluation: Its Origins, Challenges, and Unresolved IssuesHEALTH SERVICES RESEARCH, Issue 1p2 2007James R. Knickman Objective. To discuss why and how the Cash and Counseling Demonstration came to be designed, implemented, and evaluated through a partnership between the U.S. Department of Health and Human Services Office of the Assistant Secretary for Planning and Evaluation (ASPE) and the Robert Wood Johnson Foundation (RWJF). Principal Findings. This public/private partnership was created by two colleagues who were motivated by the need for funding to conduct a large-scale demonstration and evaluation, the prestige that both organizations brought to the project, the ability to draw on both organizations' experience and expertise, and the potential to maximize flexibility in the design and implementation of the demonstration. The partnership, which has lasted over a decade and has supported two generations of Cash and Counseling programs, overcame several challenges including getting approval for the project through their respective bureaucracies, managing the decision making process and the ongoing program across the two organizations, dealing with leadership and staff turnover, and reaching consensus on how to apportion credit for the success of the program. Several unresolved issues remain, including how the program gets operationalized within each state, how case management is addressed within the context of a consumer-directed model like Cash and Counseling, how quality is assured in this type of program, and how the Internal Revenue Service views and treats Cash and Counseling and other consumer-directed programs. Conclusion. This public/private partnership is an illustration of how public dollars can be leveraged effectively to examine a pressing policy issue and to produce information that can be translated into better policy and practice. The ASPE/RWJF collaboration made it possible to develop, test, and expand a policy-oriented demonstration project that has become a pivotal strategy in most states' efforts to build their home and community-based service systems. [source] Mechanism of metabolic activation and DNA adduct formation by the human carcinogen diethylstilbestrol: The defining link to natural estrogensINTERNATIONAL JOURNAL OF CANCER, Issue 6 2009Muhammad Saeed Abstract Diethylstilbestrol (DES) is a human carcinogen, based on sufficient epidemiological evidence. DES is mainly metabolized to its catechol, 3,-hydroxyDES (3,-OH-DES), which can further oxidize to DES-3,,4,-quinone (DES-3,,4,-Q). Similarly to estradiol-3,4-quinone, the reaction of DES-3,,4,-Q with DNA would form the depurinating 3,-OH-DES-6,-N3Ade and 3,-OH-DES-6,-N7Gua adducts. To prove this hypothesis, synthesis of DES-3,,4,-Q by oxidation of 3,-OH-DES with Ag2O was tried; this failed due to instantaneous formation of a spiro -quinone. Oxidation of 3,-OH-DES by lactoperoxidase or tyrosinase in the presence of DNA led to the formation of 3,-OH-DES-6,-N3Ade and 3,-OH-DES-6,-N7Gua adducts. These adducts were tentatively identified by LC-MS/MS as 3,-OH-DES-6,-N3Ade, m/z = 418 [M+H]+, and 3,-OH-DES-6,-N7Gua, m/z = 434 [M+H]+. Demonstration of their structures derived from their oxidation by MnO2 to the DES quinone adducts and subsequent tautomerization to the dienestrol (DIES) catechol adducts, which are identical to the standard 3,-OH-DIES-6,-N3Ade, m/z = 416 [M+H]+, and 3,-OH-DIES-6,-N7Gua, m/z = 432 [M+H]+, adducts. The reaction of DIES-3,,4,-Q or lactoperoxidase-activated 3,-OH-DIES with DNA did not produce any depurinating adducts, due to the dienic chain being perpendicular to the phenyl planes, which impedes the intercalation of DIES into the DNA. Enzymic oxidation of 3,-OH-DES suggests that the catechol of DES intercalates into DNA and is then oxidized to its quinone to yield N3Ade and N7Gua adducts. These results suggest that the common denominator of tumor initiation by the synthetic estrogen DES and the natural estrogen estradiol is formation of their catechol quinones, which react with DNA to afford the depurinating N3Ade and N7Gua adducts. © 2008 Wiley-Liss, Inc. [source] Demonstration of Flexible Freestanding All-Polymer Integrated Optical Ring Resonator Devices,ADVANCED MATERIALS, Issue 1 2004Y. Huang A simple method to fabricate thin freestanding all-polymer integrated optical devices and the transfer of the devices to various substrates, such as the curved surfaces of capillary tubes, is reported. A passive microring resonator optical filter device (see Figure) with a ,27,dB notch extinction for wavelengths in the telecommunication band, which is within the range of requirements for practical telecommunications applications, is also shown. [source] Triphase Hydrogenation Reactions Utilizing Palladium-Immobilized Capillary Column Reactors and a Demonstration of Suitability for Large Scale SynthesisADVANCED SYNTHESIS & CATALYSIS (PREVIOUSLY: JOURNAL FUER PRAKTISCHE CHEMIE), Issue 15 2005Juta Kobayashi Abstract We have developed a practical and highly productive system for hydrogenation reactions utilizing capillary column reactors, which occupy less space than ordinary batch systems, are low cost and easy to handle, and show feasibility toward large-scale chemical synthesis. Palladium-containing micelles were immobilized onto the inner surface of the capillaries. Nine palladium-immobilized capillaries were assembled and connected to a T-shaped connector, and hydrogen and a substrate solution were fed to capillaries via the connector. Hydrogenation of 1-phenyl-1-cyclohexene (1) proceeded smoothly to give phenylcyclohexane in quantitative yield. The capillaries themselves occupy only ca. 0.4,mL and a high space-time yield has been achieved (124.3,mg/17,min/0.4,mL). In addition, leaching of palladium was not detected by ICP analysis after reactions. [source] Demonstration of Birbeck (Langerhans cells) granules in the normal chicken epidermisJOURNAL OF ANATOMY, Issue 4 2001ARMANDO PÉREZ-TORRES Mammalian Langerhans cells (LC) are epidermal dendritic cells which originate in bone marrow and migrate toward the T cell area of lymph nodes, where they act as professional antigen-presenting cells. A variety of cell surface markers, such as the ectoenzyme adenosine triphosphatase (ATPase), Ia and CD1a antigens, have been used extensively to identify LC. Ultrastructural identification of this cell type in the mammalian epidermis is made by the demonstration of a typical and unique cytoplasmic organelle, the Birbeck granule (BG). Although we had earlier demonstrated the coexpression of ATPase and Ia antigens on epidermal dendritic cells of the chicken epidermis, the presence of the BG has not previously been documented. The aim of the present study was to investigate whether chicken epidermal LC-like cells possess an organelle similar to the BG, and thus to complete their identification. Our findings are the first demonstration of characteristic rod-shaped, racket-shaped and disc-shaped intracytoplasmic organelles, morphologically similar to the mammalian BG, in avian LC. [source] 64-Row MDCT Demonstration of an Unruptured Aneurysm of the Sinus of ValsalvaJOURNAL OF CARDIAC SURGERY, Issue 1 2010Guangyu Tang M.D. (J Card Surg 2010;25:70-71) [source] Atrial Tachycardia Originating from the Upper Left Atrial Septum: Demonstration of Transseptal Interatrial Conduction Using the Infolded Atrial WallsJOURNAL OF CARDIOVASCULAR ELECTROPHYSIOLOGY, Issue 8 2006KOJI KUMAGAI M.D. We report a rare case of atrial tachycardia (AT) originating from the upper left atrial septum. Electroanatomic mapping of both atria demonstrated that the earliest atrial activation during AT occurred at the upper left atrial septum 26 msec before the onset of the P wave, followed by the mid-right atrial septum (10 msec before the onset of the P wave) and then the upper right atrial septum just adjacent to the left septal AT site (1 msec before the onset of the P wave), indicating detour pathway conduction from the upper left to the upper right atrium. Embryologically, it was suggested that the superior components of the secondary atrial septum are made by the infolded atrial walls and could develop a transseptal detour pathway involving the left-side atrial septal musculature, the superior rim of the oval fossa and the right-side atrial septal musculature. A single radiofrequency application targeting the upper left atrial septum successfully abolished the AT. [source] Demonstration of Electrical and Anatomic Connections Between Marshall Bundles and Left Atrium in Dogs: Implications on the Generation of P Waves on Surface ElectrocardiogramJOURNAL OF CARDIOVASCULAR ELECTROPHYSIOLOGY, Issue 12 2002CHIKAYA OMICHI M.D. Marshall Bundle and P Wave.Introduction: The muscle bundles within the ligament of Marshall (LOM) are electrically active. The importance of these muscle bundles (Marshall bundle [MB]) to atrial activation and the generation of the ECG P wave is unclear. Methods and Results: We used optical mapping techniques to study epicardial activation patterns in isolated perfused left atrium in four dogs. In another seven dogs, P waves were studied before and after in vivo radiofrequency (RF) ablation of the connection between coronary sinus (CS) and the LOM. Computerized mapping was performed before and after RF ablation. Optical mapping studies showed that CS pacing resulted in broad wavefronts propagating from the middle and distal LOM directly to the adjacent left atrium (LA). Serial sections showed direct connection between MB and LA near the orifice of the left superior pulmonary vein in two dogs. In vivo studies showed that MB potentials were recorded in three dogs. After ablation, the duration of P waves remained unchanged. In the other four dogs, MB potentials were not recorded. Computerized mapping showed that LA wavefronts propagated to the MB region via LA-MB connection and then excited the CS. After ablation, the activation of CS muscle sleeves is delayed, and P wave duration increased from 65.3 ± 14.9 msec to 70.5 ± 17.2 msec (P = 0.025). Conclusion: In about half of the normal dogs, MB provides an electrical conduit between LA free wall and CS. Severing MB alters the atrial activation and lengthens the P wave. MB contributes to generation of the P wave on surface ECG. [source] Diversity patterns amongst herbivorous dinosaurs and plants during the Cretaceous: implications for hypotheses of dinosaur/angiosperm co-evolutionJOURNAL OF EVOLUTIONARY BIOLOGY, Issue 3 2009R. J. BUTLER Abstract Palaeobiologists frequently attempt to identify examples of co-evolutionary interactions over extended geological timescales. These hypotheses are often intuitively appealing, as co-evolution is so prevalent in extant ecosystems, and are easy to formulate; however, they are much more difficult to test than their modern analogues. Among the more intriguing deep time co-evolutionary scenarios are those that relate changes in Cretaceous dinosaur faunas to the primary radiation of flowering plants. Demonstration of temporal congruence between the diversifications of co-evolving groups is necessary to establish whether co-evolution could have occurred in such cases, but is insufficient to prove whether it actually did take place. Diversity patterns do, however, provide a means for falsifying such hypotheses. We have compiled a new database of Cretaceous dinosaur and plant distributions from information in the primary literature. This is used as the basis for plotting taxonomic diversity and occurrence curves for herbivorous dinosaurs (Sauropodomorpha, Stegosauria, Ankylosauria, Ornithopoda, Ceratopsia, Pachycephalosauria and herbivorous theropods) and major groups of plants (angiosperms, Bennettitales, cycads, cycadophytes, conifers, Filicales and Ginkgoales) that co-occur in dinosaur-bearing formations. Pairwise statistical comparisons were made between various floral and faunal groups to test for any significant similarities in the shapes of their diversity curves through time. We show that, with one possible exception, diversity patterns for major groups of herbivorous dinosaurs are not positively correlated with angiosperm diversity. In other words, at the level of major clades, there is no support for any diffuse co-evolutionary relationship between herbivorous dinosaurs and flowering plants. The diversification of Late Cretaceous pachycephalosaurs (excluding the problematic taxon Stenopelix) shows a positive correlation, but this might be spuriously related to poor sampling in the Turonian,Santonian interval. Stegosauria shows a significant negative correlation with flowering plants and a significant positive correlation with the nonflowering cycadophytes (cycads, Bennettitales). This interesting pattern is worthy of further investigation, and it reflects the decline of both stegosaurs and cycadophytes during the Early Cretaceous. [source] Demonstration of a new calibration standard for strontium measurements in otoliths based on high energy Sr ion implantationJOURNAL OF FISH BIOLOGY, Issue 3 2002R. W. Gauldie A new Sr measurement standard is given for biominerals based on implanting an exactly known number of Sr atoms into an otolith section using ion-beam implantation and pre- and post-implantation ion beam (PIXE) scanning. [source] The role of the pectoral fins in body trim of sharksJOURNAL OF FISH BIOLOGY, Issue 5 2000F. E. Fish In a large aquarium the leopard shark Triakis semifasciata, sand tiger shark Odontaspis taurus, sandbar shark Carcharhinus plumbeus, and spiny dogfish Squalus acanthias cruised steadily at 0·1-0·7 body lengths s -1. Relative to the trajectory of the shark, the pectoral fins were maintained at a positive angle of ttack regardless of vertical direction. For level swimming the mean angle of attack for the pectoral fin was 11±1·7, 10·1±1·3°, 9·3±1·3°, and 15·0±0·0 for T. semifasciata, C. plumbeus, O. taurus, and S. acanthias, respectively. The long axis of the body was canted at an angle of attack for T. semifasciata and S. acanthias, but trim was maintained during level swimming for C. plumbeus and O. taurus. Hydrodynamic analysis of the body and fin design of T. semifasciata indicated that the pectoral fins could develop suffcient pitching moment to maintain depth and keep the body in trim. Demonstration of positive angles of attack support the hypothesis that lift is generated in the anterior body to counterbalance the lift produced by the heterocercal tail. [source] Spatial Governance and Working Class Public Spheres: The Case of a Chartist Demonstration at Hyde ParkJOURNAL OF HISTORICAL SOCIOLOGY, Issue 3 2001John Michael Roberts The concepts of the public sphere and public space have gained increasing purchase within social history. This paper contributes to this literature by theoretically developing a critical approach to both concepts. By drawing upon the insights of the Bakhtin circle, as well as Marxism and Poststructuralism, the paper suggests that public spheres under capitalism are structured through the basic contradiction between capital and labour. Each public sphere may then be seen as a refracted dialogic and spatial form of this basic contradiction, and is then best viewed as a contradictory spatial entity that obtains its unique identity through different "accents" and "word signs". The capitalist state must aim to regulate, through governance and law, dialogue within a public sphere. By focusing on the Chartist demonstration at Hyde Park, London in 1855, I show how these theories can be employed to explore how a radical social movement appropriated space by developing a working class public sphere. [source] Intrahepatic arterioportal fistula: Demonstration by dynamic 3D magnetic resonance angiography in under four secondsJOURNAL OF MAGNETIC RESONANCE IMAGING, Issue 1 2002N. Cem Balci MD Abstract We report a case of a 35-year-old patient with clinical symptoms of portal hypertension that underwent dynamic contrast-enhanced 3D magnetic resonance angiography (MRA) of the abdomen. On breath-hold dynamic contrast-enhanced MRA in less than 4 seconds, contrast passage from the arterial to the portal system was successfully demonstrated. Patient was managed according to MRA findings. J. Magn. Reson. Imaging 2002;16:94,96. © 2002 Wiley-Liss, Inc. [source] Acute retinal necrosis six years after herpes simplex encephalitis: An elusive immune deficit suggested by insufficient test sensitivityJOURNAL OF MEDICAL VIROLOGY, Issue 2 2004W. Preiser Abstract A patient presented with acute retinal necrosis of the left eye. Demonstration of herpes simplex virus (HSV) DNA in the aqueous humour confirmed the diagnosis. Negative results of HSV type-specific antibody tests based on gG antigens suggested a primary HSV infection. However, the patient had a past history of laboratory-confirmed herpes simplex encephalitis 6 years ago. Using antibody tests based on whole viral lysate antigens, he was seropositive from the onset, and immunoblot testing confirmed a lack of anti-gG reactivity. To be able to assess whether this might be related to the apparent inability of his immune system to suppress clinically symptomatic HSV infection, serial samples were tested by an HSV neutralisation test and a whole-blood flow cytometric assay to determine the frequency of HSV-specific CD4 lymphocytes. However, this did not yield evidence of obvious immunodeficiency; the patient reacted similarly to known positive controls by both assays. Although type-specific HSV serological tests based on gG are generally more specific than those based on whole viral lysate antigens, they have a somewhat lower sensitivity, as a certain percentage of HSV-infected individuals do not develop antibodies against gG, and others may suffer a secondary loss of anti-gG reactivity. Thus there is a risk of missing individual infected patients. Unless this potential problem is recognised, serious consequences might possibly result. We therefore urge virologists and clinicians to exercise great care if highly specific antibody assays based on recombinant proteins are employed. J. Med. Virol. 73:250,255, 2004. © 2004 Wiley-Liss, Inc. [source] Demonstration of Postsynaptic Receptor Plasticity in an Amphibian Neuroendocrine InterfaceJOURNAL OF NEUROENDOCRINOLOGY, Issue 11 2002B. G. Jenks Abstract Pituitary pars intermedia melanotrope cells are often used as a model to study mechanisms of neuroendocrine integration. In the amphibian Xenopus laevis, the synthesis and release of ,-melanophore-stimulating hormone (,-MSH) from these cells is a dynamic process dependent upon the colour of background. In animals on a black background, there is a higher level of synthesis and secretion of ,-MSH than in animals on a white background, and, consequently, there is skin darkening in animals on a black background. The melanotropes are innervated by hypothalamic neurones that produce neuropeptide Y (NPY), a peptide that inhibits ,-MSH secretion via the NPY Y1 receptor. The inhibitory neurones have a higher expression of NPY in animals adapted to a white background and both the size and the number of inhibitory synapses on the melanotrope cells are enhanced. The purpose of the present study was to determine if this presynaptic plasticity displayed by the inhibitory neurones is reciprocated by postsynaptic plasticity (i.e. if there is an enhanced expression of the Y1 receptor in melanotropes of animals adapted to a white background). For this purpose quantitative real-time reverse transcriptase-polymerase chain reaction was used to determine the level of Y1 receptor mRNA in melanotropes of animals undergoing the process of background adaptation. The results showed that there is a higher Y1 receptor mRNA expression in melanotropes of white-adapted animals. We conclude that the inhibitory neuroendocrine interface in the Xenopus pars intermedia displays postsynaptic plasticity in response to changes of background colour. To our knowledge, this is the first demonstration of a physiological environmental change leading to changes in postsynaptic receptor expression in a fully identified vertebrate neuroendocrine reflex. [source] Demonstration of hydroxyindole-O-methyltransferase (HIOMT) mRNA expression in pineal parenchymal tumors: Histochemical in situ hybridizationJOURNAL OF PINEAL RESEARCH, Issue 4 2000Itaru Tsumanuma The expression of hydroxyindole-O-methyltransferase (HIOMT), an enzyme catalyzing the final step of melatonin biosynthesis, was examined in three pineoblastomas and five pineocytomas by in situ hybridization analysis. Distinct hybridization signals for HIOMT mRNA, though weaker than in normal pineal gland pinealocytes, were detected in two of the three pineoblastoma and three of the five pineocytoma cases. Of the pineoblastomas, hybridization signals were observed in most tumor cells of one case, while in another, signals were detected in occasional cells clustered or scattered throughout the neoplastic field. Of the pineocytomas, signals were detected in most tumor cells of two cases, while in one case, signals were detected only in occasional cells. Among these specimens, one pineoblastoma and one pineocytoma were also analyzed using northern blot and reverse transcription polymerase chain reaction (RT-PCR) analyses. In the northern blot analysis, an apparently single band corresponding to the size of HIOMT mRNA was detected in both pineoblastoma and pineocytoma RNA blots. In the RT-PCR analysis, three species of HIOMT mRNA generated via alternative splicing were detected in both tumors. These results suggest that the neoplastic cells of pineoblastomas and pineocytomas often retain the ability to express HIOMT mRNA, as in normal pinealocytes, and that HIOMT is a useful tumor marker for the diagnosis of pineal parenchymal tumors. [source] Vitamin D and Bone Physiology: Demonstration of Vitamin D Deficiency in an Implant Osseointegration Rat ModelJOURNAL OF PROSTHODONTICS, Issue 6 2009James Kelly DDS Abstract Purpose: The patient population varies in nutritional deficiencies, which may confound the host response to biomaterials. The objective of this study was to evaluate the effect of a common deficiency of vitamin D on implant osseointegration in the rat model. Materials and Methods: Male Sprague-Dawley rats were maintained under the cessation of vitamin D intake and UV exposure. The serum levels of 1,25(OH)2D3, 25 OHD3, Ca, and P were determined. Miniature cylindrical Ti6Al4V implants (2-mm long, 1-mm diameter) were fabricated with double acid-etched (DAE) surface or modified DAE with discrete crystalline deposition (DCD) of hydroxyapatite nanoparticles. DAE and DCD implants were placed in the femurs of vitamin D-insufficient and control rats. After 14 days of healing, the femur-implant samples were subjected to implant push-in test and nondecalcified histology. The surfaces of recovered implant specimens after the push-in test were further evaluated by scanning electron microscopy (SEM). Results: The decreased serum level of 25 OHD3 demonstrated the establishment of vitamin D insufficiency in this model. The implant push-in test revealed that DAE and DCD implants in the vitamin D-insufficient group (15.94 ± 8.20 N, n = 7; 15.63 ± 3.96 N, n = 7, respectively) were significantly lower than those of the control group (24.99 ± 7.92 N, n = 7, p < 0.05; 37.48 ± 17.58 N, n = 7, p < 0.01, respectively). The transcortical bone-to-implant contact ratio (BIC) was also significantly decreased in the vitamin D-insufficient group. SEM analyses further suggested that the calcified tissues remaining next to the implant surface after push-in test appeared unusually fragmented. Conclusions: The effect of vitamin D insufficiency significantly impairing the establishment of Ti6Al4V implant osseointegration in vivo was unexpectedly profound. The outcome of Ti-based endosseous implants may be confounded by the increasing prevalence of vitamin D insufficiency in our patient population. [source] Human rectal adenocarcinoma: Demonstration of 1H-MR spectra in vivo at 1.5 TMAGNETIC RESONANCE IN MEDICINE, Issue 4 2002A.S.K. Dzik-Jurasz This study was designed to determine whether 1H-MR spectra of locally advanced human rectal adenocarcinoma could be acquired in vivo at 1.5 T. Despite the relatively large size of these neoplasms, only six out of 21 tumors accommodated a voxel size of 8 cm3. This was due to air pockets within the tumor mass, which limited voxel positioning. Localized proton spectra were acquired at short (20 ms) and long (135 ms) echo times (TEs) using a single-voxel technique. The most commonly detected metabolites were choline and lipid. Magn Reson Med 47:809,811, 2002. © 2002 Wiley-Liss, Inc. [source] | ||||||||||||||||||||||||||||||||||||||||||||||||||||