bluuebunny/crossref_metadata_2025 huggingface dataset:
Numerical Modelling of Electrically Enhanced Fibrous Filtration
Authors: Henry F. S. , Ariman Teoman
Published: September 2009

Numerical solutions of the flow through a model fibrous filter are used to study electrically enhanced filtration. It is shown that numerical modelling, or simulation, has advantages over both the analytical and the experimental approach. Particle trajectories are presented, and filter efficiencies are predicted and compared to experimental data. The dendritic structure of the particle deposit is also investigated. Differences in dendrite structure seen in the laboratory between enhanced and non-enhanced collection are also simulated.
Effects of Particle Deposition on the Performance of Granular Filters
Authors: Tien Chi
Published: September 2009

A review is presented of the effect of particle deposition on the performance of granular filters. The extent to which this effect can be incorporated into the design calculations and the major problems to be solved are discussed.
Respirator Filtration Efficiency Testing
Authors: Moyer Ernest S.
Published: September 2009

The existing methods for evaluating particulate respirator filters as found in 30 CFR Part 11 are presented. Shortcomings with these methods are discussed in detail. NIOSH's research objectives for updating particulate respirator filter testing are presented along with some research findings. Conclusions are drawn from these results and areas of future research in respirator particulate filter evaluation are stated.
Quantitative Fit Testing of Respirators: Past, Present, Future
Authors: Myers Warren R.
Published: September 2009

The historical development of quantitative techniques to evaluate the “fit” of a respirator on a particular wearer is reviewed. The inferences drawn from such testing with regard to protection or selection of the “best fitting facepiece” are examined in light of new research data recently obtained from field and laboratory studies. Areas of research for improving quantitative fit testing are identified.
Filtration as a Method for Air Quality Control in Occupied Spaces
Authors: Woods James E , Krafthefer Brian C.
Published: September 2009

Filtration, or removal control, is one of three methods currently available to provide acceptable indoor air quality in occupied spaces. While the other two methods, source and dilution control, are primarily employed for occupant needs, filtration has conventionally been used for protection of components within the heating, ventilating, and air conditioning systems. In this paper, filtration technology is reviewed with respect to current ventilation standards for occupants. The difference between ventilation and air quality control is discussed in terms of acceptability criteria and control methods. Parameters that relate these terms are identified and control strategies are proposed that can be used to optimize removal and dilution methods for occupant acceptability and cost-effectiveness.
Air Cleanliness Requirements for Clean Rooms
Authors: King J. Gordon
Published: September 2009

The cleanlines of air required for clean rooms is defined in terms of nature, quantity, size distribution, test methods and removal mechanisms of contaminants. Test instrumentation is described and some practical limitations are given. Included is information regarding some of the changes recommended by the Institute of Environmental Sciences for the latest revision of Federal Standard 209. Some projections are made for what future clean room air cleanliness may be required. Present knowledge indicates that future cleanliness needs beyond the present limits may be restricted to very small, confined zones, where exposure to contamination is transient and of short duration.
The Durability of Polyethylene Piping
Authors: Mruk Stanley A.
Published: September 2009

A review of the literature on the physical and chemical aging of polyethylene piping has been undertaken. In typical uses the only types of aging mechanism that may limit polyethylene (PE) pipe's durability are photodegradation, oxidative degradation, and slow crack growth under tensile stressing.

Current generation PE pipe grade materials have superior resistance to these forms of aging. This resistance has been confirmed by accelerated aging testing, by fracture mechanics testing, and by evaluating pipes after long service histories.

Appropriate requirements, test methods, and protocols have been incorporated into product standards to adequately protect commercial grade PE piping against aging over the long service life expected in public utility and similar applications.
Vertical Deflection of Buried Flexible Pipes
Authors: Greenwood Mark E. , Lang Dennis C.
Published: September 2009

For over 50 years, studies of soil-pipe interaction have provided methods to predict vertical deflection of buried flexible pipes. Several of these methods are widely used in standards. However, these methods do not account for many of the recognized parameters that affect buried pipe behavior. Based on recent research findings, empirically-based modifications are introduced to the original Spangler approach to obtain a new calculation method for estimating vertical flexible pipe deflection. Development, applications and limitations of this method are presented. Comparison studies of the new method and that presented in ANSI/AWWA C950-88 "AWWA Standard for Fiberglass Pressure Pipe" (which is based on the modified Iowa formula) versus actual field measurement data are included. These studies present correlation of predicted versus measured values as well as similarities and differences between the methods.
Large Diameter Sewer Rehabilitation by Sliplining in Florida
Authors: Collins John E.
Published: September 2009

Case history of two large diameter sanitary sewer rehabilitation projects in Florida. The projects, located in Jacksonville and Tampa, involved the rehabilitation of deteriorated reinforced concrete pipe (RCP) by sliplining new centrifugally cast fiberglass pipe into the interior of the existing RCP. The projects are described from the planning stage; including an evaluation of replacement versus rehabilitation; the design stage, which specified a pipe product that would be a structural- and corrosion-resistant alternative to replacement and the construction stage, ensuring not only conformance to installation requirements but product compliance through laboratory testing.
Bonded Metal-to-Metal Shear Testing
Authors: Lunsford Lee R.
Published: September 2009

The factors affecting joint strength, the different specimen types, and the properties actually evaluated by each type are discussed in detail. These properties are compared with the properties of a bonded joint which actually allow failure to take place. It points out that most methods presently used are empirical, and serious errors could be obtained in extrapolating this information to other materials or environments. The possibilities of predicting joint strength from basic material properties are discussed. The paper includes a discussion of the difficulties encountered in bonding titanium joints where the adherend strain is approximately twice that of steel or aluminum. These principles are incorporated into a method of analysis in which the shear modulus of the adhesive becomes very important.
The Preparation and Maintenance of High-Purity Water
Authors: Alquist F. N.
Published: September 2009

In a nuclear reactor power system (1) using water as a coolant and moderator, high-purity water is a necessity. The preparation and maintenance of high-purity water can be accomplished with ion exchange methods which must be provided as an integral part of the reactor. Ion exchange, as discussed in this paper, is used in reactors to control (1) direct and transport corrosion, (2) water decomposition, (3) induced water radioactivity, and (4) neutron economy. In order to maintain high-purity water, a portion of it is continuously by-passed through a filter and an ion exchange bed to remove insoluble and soluble cations and anions.
Standardization in Sweden
Authors: Broberg Walter
Published: September 2009

The national standards body in Sweden is the Swedish Standards Assn. (SIS) a private organization established in 1922 on the initiative of the Federation of Swedish Industries.
Encyclopedia of Electrical Insulating Materials
Authors: de Senarclens G.
Published: September 2009

The judicious selection of insulating materials plays a predominant role in the functioning and life of an electrical machine or apparatus. However, this selection is becoming more and more difficult because of the increasing number of insulating materials, their rapid evolution, and the variety of requirements to be met. The technical information available does not always apply to the use to which they are destined and too often does not allow comparison between different types. Their weak points are described with caution. The engineer who calculates and builds an electrical machine rarely has the chemical knowledge to foresee the chemical behavior of the insulating materials under variable service conditions so he must consult a great number of specialized publications. Finally, insulating materials which belong to the same class but which differ greatly in their properties frequently have the same commercial designation.
Research on Vibratory Maximum Density Test for Cohesionless Soils
Authors: Pettibone H. C. , Hardin J.
Published: September 2009

The use of relative density as a method of control for compaction of cohesionless soils is hampered by lack of an adequate method for determining the maximum soil density. Previous investigations have shown that higher densities are obtained for most cohesionless soils by vibratory methods than by the standard impact compaction methods. This paper presents the results of an investigation of vibratory methods to determine the combination of variables which would give the highest density. Four electromagnetic table-type vibrators, an immersion-type concrete vibrator, and a pneumatic table-type vibrator were used in this investigation. The effect on the soil density of magnitude of surcharge, time of vibration, amplitude of vibration, and water content were studied for seven cohesionless soils representing a wide range in gradations. A summary of the Bureau of Reclamation's test procedure for determining the relative density of cohesionless soils using a vibratory table is included. For the range of amplitudes investigated, maximum densities were generally obtained at the higher amplitudes. Additional research is needed to determine the optimum deadweight surcharge. The increase in density was insignificant for times of vibration greater than 6 min, and 8 min seems to be a reasonable and sufficient time for the equipment and soils tested. The initial density of the soil prior to vibration did not have a significant effect on the final density. The difference between the densities obtained using oven-dried soil and initially saturated soil was not significant for most of the soils tested.
Effects of the Ascent Environment on Spacecraft Thermal Control Surfaces
Authors: Schmidt W. F. , Haslim L. A. , McKellar L. A.
Published: September 2009

A résumé of the ascent environment of a spacecraft is presented, and a program to test the effects of that environment on candidate thermal control surfaces is outlined. Routine tests employ radiant heating in a reduced pressure environment. The apparatus and test criteria are described. Results of tests on materials considered for use on Lockheed Missiles and Space Co. (LMSC) spacecraft are presented. Criteria for material behavior are: the resultant alteration in emittance, solar absorptance, and mechanical stability. Failure modes are discussed. Conclusions are drawn regarding the behavior of various classes of materials in the ascent environment. The white solar reflector surfaces are most susceptible to damage. The best black paint surface tested performed adequately at temperatures in excess of 1000 F; the best white paint failed at temperatures above 700 F.
Compressive Properties of Pyrolytic Graphite from Room Temperature to 5000 F
Authors: Gobble L. P. , Salmen W. J.
Published: September 2009

The objective of this test was to determine the compressive properties of pyrolytic graphite when loaded parallel to the a-b planes at temperatures from room temperature to 5000 F after heating at rates of 400 F per sec. Loading was programmed at a rate of 1000 psi per sec.

Pyrolytic graphite behaved in a brittle manner at all test temperatures. Average room temperature properties are: compressive strength, 13,500 psi; elastic modulus, 3.5 × 106 psi. The compressive strength decreased 6 per cent and the elastic modulus decreased 13 per cent in the range from room temperature to 3500 F. From 3500 to 5000 F a sharp decrease in compressive strength and elastic modulus occurred. Average properties at 5000 F are: compressive strength, 9700 psi; elastic modulus, 1.5 × 106 psi.

The proportional limit of pyrolytic graphite at a given temperature is approximately 25 per cent of the compressive strength. Typical stress-strain curves for specimens tested up to 5000 F are presented. Special equipment and test techniques used to obtain the required properties are described.
Testing Materials in a Plasma Arc Under Simulated Re-Entry Conditions
Authors: Hagan M. A. , Martin George
Published: September 2009

The problem of materials for re-entry vehicles is unique in that the design criteria by which a material was selected in the past is no longer sufficient. For example, strength versus temperature data, section modulus, and similar traditional structural properties are of limited value where a material must perform in environments approaching or at its softening point. Temperature gradients, thermal shock, chemical reactions, erosion rates, producibility, and other related properties now assume a much greater importance than ever before. The material requirement that must be determined at temperatures above 3000 F may be categorized as follows: (1) maintenance of structural integrity under aerodynamic loads, (2) thermal shock resistance, (3) ability to withstand large thermal gradients and (4) surface resistance against corrosion and erosion.
Creep Crack Growth Predictions in Component Using a Damage Based Approach
Authors: Yatomi Masataka , Nikbin Kamran M.
Published: September 2009

This paper presents a numerical study of simulated creep crack growth (CCG) prediction in a compact tension [C(T)] specimen and a pipe component containing cracks. The results are compared to experimental data of the same consisting of creep crack growth tests of a carbon-manganese steel (C-Mn) tested at 360°C. The constitutive behavior for this steel is described by a power law creep model and the uniaxial properties are used in a damage based model to predict CCG. For comparison between CCG properties of the pipe and C(T) specimens, different reference stress methods were used to derive appropriate C* values. It has been shown that the global solution for collapse in the cracked pipes gives the best correlation with the C(T) data. On this basis CCG rates for pipe are higher than those for C(T) specimens at the same value of C*. The damage-based approach combined with a crack tip constraint model based on void growth is also used to predict the crack propagation rates in the pipe component using a twodimensional finite elements (FE) mesh. Elastic-plastic-creep analyses are performed using a node debonding criteria to simulate and predict crack extension under plane stress and plane strain conditions. It has been found that CCG against time predicted from the FE under plane stress conditions is almost the same as those for the experimental data. Comparing C* derived from different reference stress methods to C* from FE analysis it has been found that C* from FE under plane strain condition correlates best with C* from the global reference stress solution. Consequently the main CCG difference between the C(T) and the pipe component is found to be due to the method of estimating C* and not due to constraint effects.
Fatigue Strength in Presence of Inhomogeneities: Influence of Constraint
Authors: Beretta Stefano , Carboni Michele , Madia Mauro
Published: September 2009

The effect of defects on the entity of the fatigue limit is nowadays well known and is demonstrated to be equivalent to the nonpropagating condition of short cracks. The influence of constraint at the defect tip has been addressed in the present paper considering a mild steel whose mechanical behavior has been experimentally determined together with the propagation threshold values for long cracks. The activity has first dealt with the determination of the Kitagawa diagram by means of fatigue limit tests using specimens containing micro-notches with different shapes (drilled holes and narrow slits). Experimental results showed a significant influence of the defect shape on the fatigue limit and thresholds. In order to understand the reasons, defects have then been analyzed by elasto-plastic FEM analyses. Computational results have confirmed a significant difference in the global constraint factor at the crack tip between round and narrow defects.
Development of a Circumferentially Throughwall Cracked Tube Specimen for Fatigue Crack Growth Rate Tests
Authors: Young Bruce A. , Sluys W. Alan Van Der , King Peter J.
Published: September 2009

This paper describes the development of a nonstandard specimen geometry for fatigue crack growth rate studies. Most fatigue crack growth rate data, available in open literature, for Alloy 690 and Alloy 600 were developed using standard, thick section C(T) specimens. Recently a need arose to study a circumferentially throughwall cracked tube specimen. The goal of the development was to use this tube specimen to determine any effects of section thickness or grain size on corrosion enhancement of fatigue crack growth rates in a simulated pressurized water reactor (PWR) primary side environment. Along with the final specimen geometry, the stress intensity equation and crack length monitoring equation are discussed. The stress intensity equation was converted to a standard polynomial equation in order to use a conventional automated fatigue crack growth rate software package. Symmetry arguments were made to justify the use of direct current potential drop (DCPD) and the use of the standard Johnson's equations for measuring crack lengths. Also, some discussions of the validity requirements for this geometry are presented such as stress intensity limits to remain with linear elastic fracture mechanics (LEFM) bounds and crack length limits to avoid excess bending stresses. A baseline test program was conducted on Alloy 690 tube specimens in ambient air and these results were compared with literature data. Also, a sensitivity investigation was preformed to determine the error between the polynomial equations developed and the actual equations in literature. The results of this study confirmed that a circumferentially cracked tube specimen could produce valid fatigue crack growth rate data.
Elastic T-Stress Solutions of Embedded Elliptical Cracks Subjected to Uniaxial and Biaxial Loadings
Authors: Qu Jie , Wang Xin
Published: September 2009

The elastic T-stress has been found to be an important parameter in characterizing the near crack tip elastic-plastic stress states of 2-D and 3-D crack problems. In addition to the J-integral, the T-stress provides an effective two-parameter characterization of 2-D and 3-D elastic-plastic crack tip fields in a variety of crack configurations under small scale yielding conditions. Embedded elliptical crack in an infinite solid subjected to uniaxial or biaxial tension conditions represents an excellent model for many engineering components with embedded cracks. Although extensive analyses are available for stress intensity factors (SIFs) for embedded elliptical cracks, to date no analytical T-stress solutions are available. This paper presents the exact close form solutions for elastic T-stress of an embedded elliptical crack in an infinite body under remote uniaxial or biaxial tension. The foundation of the derivation is based on the potential method for three-dimensional elasticity. Solutions of stress components parallel to and perpendicular to the cracked plane are derived first. T-stress is then obtained from the asymptotic stress field near the crack front. Complete solutions of T-stress along the crack front are established. Further, three-dimensional finite element analyses are conducted to verify the derived solutions; excellent agreements are achieved. When combined with the corresponding K or J solutions, these T-stress solutions are suitable for the analysis of constraint effects for embedded elliptical shaped cracks in engineering components.
An Investigation of Specimen Geometry Effects on the Fracture Behavior of a Polytetrafluoroethylene Polymer
Authors: Joyce J. A. , Joyce P. J.
Published: September 2009

Recent interest by the U.S. Navy in metal filled polymers for weapons applications has resulted in a desire to characterize interactions between polymer properties associated with strain rate sensitivity, pressure sensitivity, failure mechanisms, damage mechanisms, spall strength, crystalline response to shock loading, and dynamic fracture mechanics as well as the effects of loading the polymer with various metal fillers [1]. Polytetrafluoroethylene (PTFE) is an important structural polymer that in the “7C” derivative is used for gaskets, bearing pads, piston rings, and diaphragms and when 5μm aluminum spheres are added, has important ballistic properties. Prior work [2–4] evaluated the fracture toughness of PTFE and aluminum filled PTFE over a range of temperatures and loading rates using compact tension (C(T)) specimens and the normalization method [5–7] described in Annex A15 of ASTM E 1820. Moreover, prior work [3] has shown that filling the PTFE with 10 to 25% aluminum 5μm spheres can increase stiffness and strength while the effect on toughness can be either positive or negative depending on the loading rate and test temperature. The overall effect on fracture toughness properties derived from adding the aluminum spheres to the PTFE is small and for that reason the unfilled PTFE material was used here to study the effects of geometry on fracture toughness in this material. The normalization method was initially chosen for this project because of the scarcity and cost of specimen material, especially the filled, reactive material, the many different test conditions to be investigated, and the inadequacy of alternative methods. It was quite fortunate that the normalization method was used initially to characterize this polymer since the fracture toughness resistance curves of this material often contains ductile instabilities or “pop-ins” which would not have been well characterized by multispecimen methods. The objective of this work is to compare the fracture toughness measurements obtained from C(T) and precracked Charpy (SE(B)) specimens tested under similar test conditions. A comparison is also made between J-R curves obtained using the single specimen normalization method and the “Basic” or multispecimen procedure. A limited study of the effects of side grooving on the crack extension and on the resulting J-R curves is included here.
Temperature Dependence and Variability of Fracture Toughness in the Transition Regime for A508 Grade 4N Pressure Vessel Steel
Authors: Leax T. R.
Published: September 2009

A508 Grade 4N is a high nickel (3.4 %) pressure vessel steel with a relatively high yield strength (585 MPa minimum for Class 1) and a relatively low transition temperature (47 J transition temperature of -29°C or below). Published fracture toughness data on this steel are nonexistent, and so they have not been included in prior assessments of the applicability of the Master Curve approach to pressure vessel steels. The purpose of this study is to compare the temperature dependence and data scatter for this steel with the behavior predicted by the Master Curve. The available database consists of approximately 800 fracture toughness tests on 51 material heats, some of which were given a temper embrittling heat treatment. As an additional basis of comparison, test data on A508 Grades 2 and 3, 1 % nickel weld metal, and several high nickel (1.3–3.8 %) steels (NiCrMo and NiCrMoV) were included in the assessment. Maximum likelihood techniques were used to fit the toughness data, and Monte Carlo methods were used to assess the observed distribution of Weibull slopes (related to the extent of variability). The results of this assessment show that the Master Curve provides a good description of the shape (temperature dependence) of the toughness curve for moderate and high transition temperatures. However, for heats with low transition temperatures below the range observed in other pressure vessel steels, the shape of the toughness curve deviates from the Master Curve. The lower the transition temperature, the larger the deviation from the Master Curve. Based on the test data, a model describing the behavior of A508 Grade 4N has been developed. This model also accurately describes the toughness behavior of the other pressure vessel steels included in this study. With respect to variability, the Weibull slope of A508 Grade 4N is consistent with the value of four prescribed by the Master Curve. However, the Weibull slope for the other pressure vessel steels included in this assessment is close to 3.4. This lower value of the Weibull slope, which indicates larger variability, is likely the result of material inhomogeneity.
Negative Shift in the Glycine Reversal Potential Mediated by a Ca2+- and pH-Dependent Mechanism in Interneurons
Authors: Kim Yuil , Trussell Laurence O.
Published: September 2009

Cartwheel cells are glycinergic auditory interneurons which fire Na+- and Ca2+-dependent spike bursts, termed complex spikes, and which synapse on both principal cells and one another. The reversal potential for glycine (Egly) can be hyperpolarizing or depolarizing in cartwheel cells, and many cells are even excited by glycine. We explored the role of spike activity in determiningEglyin mouse cartwheel cells using gramicidin perforated-patch recording.Eglywas found to shift toward more negative potentials after a period of complex spiking or Ca2+spiking induced by depolarization, thus enhancing glycine's inhibitory effect for ∼30 s following cessation of spiking. Combined perforated patch electrophysiology and imaging studies showed that the negativeEglyshift was triggered by a Ca2+-dependent intracellular acidification. The effect onEglywas likely caused by bicarbonate-Cl−exchanger-mediated reduction in intracellular Cl−, as H2DIDS and removal of HCO3−/CO2inhibited the negativeEglyshift. The outward Cl−flux underlying the negative shift inEglyopposed a positive shift triggered by passive Cl−redistribution during the depolarization. Thus, a Ca2+-dependent mechanism serves to maintain or enhance the strength of inhibition in the face of increased excitatory activity.
Regulation of endometrial vascular remodelling: role of the vascular endothelial growth factor family and the angiopoietin–TIE signalling system
Authors: Girling Jane E , Rogers Peter A W
Published: September 2009

Angiogenesis, lymphangiogenesis and vascular maturation occur on a regular, physiological basis in human endometrium. These processes form part of a continuum of vascular remodelling involving numerous regulatory factors. Key factors include vascular endothelial growth factor (VEGF)A, VEGFC and VEGFD, and their associated receptors VEGFR1, VEGFR2 and VEGFR3. A second group of vascular regulatory proteins belongs to the angiopoietin (ANG)–TIE system. Although members of the VEGF family and the ANG–TIE system are represented in the endometrium, our understanding of how these different molecules interact to regulate remodelling of the blood and lymphatic vasculature present in the endometrium is still limited. A review of the current information is provided.
Art de Mojopahit et art du Pasisir
Authors: Tjandrasasmita Uka
Published: September 2009

1. Uka Tjandrasasmita (National Centre for Archeology, Jakarta) emphasizes the parallels existing between the decorative motifs of the Mojopahit time and patterns from slightly later time which are to be found on the main Islamic buildings on the north coast of Java (Pasisir). In particular he mentions the famous tomb of Sunan Gunung Jati and publishes, for the first time, photographs of the tomb with the "influence" of Mojopahit clearly visible.
Les maîtres de silat d'origine chinoise, contribution à l'histoire des arts martiaux dans l'Archipel
Authors: Lombard Denys
Published: September 2009

D. Lombard (E.H.E.S.S., Paris) gives a short survey about the part played by Chinese masters of fighting arts in the development of the martial arts in the Archipelago. After having stressed several aspects of the silat : ritual, spectacular, rebellious and of religious groups, the author évoques some remarquable Chinese silat masters and sketches an outline of the evolution of tendencies of the fighting arts in Indonesia.
Notes sur les Balé du sud-ouest de l'Éthiopie
Authors: Bader Christian
Published: September 2009

Résumé : Dispersés dans la vallée de la Kaari, au sud de l'Akobo, dans l'une des régions les plus isolées de toute l'Ethiopie, les Balé-Zilmamu forment, avec les «Kachepo» du Soudan, une ethnie encore peu étudiée. Tirant l'essentiel de leurs ressources de l'agriculture, les Balé, dont le territoire est peu à peu rogné au nord par l'expansion des Anywak et au sud par les incursions des Tirma, constituent l'exemple d'un groupe humain dont la culture a subi l'influence des peuples voisins. Par leur langue et leur économie, ils sont en effet proches des Mûrie agriculteurs du Plateau de Borna, au Soudan, et des Ngalam de la vallée de l'Erbu. Leurs coutumes (dont le port de gigantesques labrets et la pratique des combats rituels au bâton) les rapprochent en revanche des tribus dites «Surma», avec lesquelles ils entretiennent pourtant des relations souvent tendues.
Aläqa Ayyälä : un peintre d'église du Wällo ou la peinture comme exercice spirituel
Authors: Rodriguez Natalia , Hirsch Bertrand
Published: September 2009

Résumé : Aläqa Ayyälä est un peintre éthiopien (c. 1909-1960) qui a réalisé des peintures mobiles sur toile pour de nombreuses églises de sa région, le Borâna (Wâllo), ou de régions voisines. Les auteurs reconstituent sa biographie, aux forts accents hagiographiques, et analysent douze de ses toiles et leurs thèmes religieux pour dégager les principes de cette création d'images chrétiennes dans l'Ethiopie contemporaine.
New sites of South Ethiopian rock engravings : Godana Kinjo, Ejersa Gara Hallo, Laga Harro, and remarks on the Šappe-Galma school
Authors: Le Quellec Jean-Loïc , Abegaz Gizachew
Published: September 2009

Summary : We present here three totally new sites discovered in 1999-2000 by Gizachew Abegaz in the area of Dilla, as well as new data on a site already known, that of Soka Dibica, before setting the whole back in the regional artistic context of the Sappe-Galma school.
Un cas de censure politique au XVIIe siècle : la chronique de Śarṣa-Dəngəl
Authors: Kropp Manfred
Published: September 2009

Résumé : La censure semble bien être un trait commun à la tradition humaine et à la mémoire collective. L'historiographie éthiopienne n'échappe pas à cette règle. Le plus souvent produite à la cour royale, elle était donc nettement sous le contrôle du pouvoir et des puissants. Ainsi les chroniques des souverains éthiopiens narrent les événements d'un règne en plein accord avec les vues officielles, fait que l'historien qui s'en sert comme source historique doit prendre en considération. La chronique de Sarsa-Dangal offre un cas de censure postérieure : les changements dramatiques dans l'histoire éthiopienne après la mort de ce souverain (une autre ligne dynastique qui se convertit au catholicisme) exigent que des passages historiques se référant aux actions du roi (Sarsa-Dangəl) et de certains de ses favoris soient changés. Les raisons de cette censure sont diverses : d'une part l'image du roi semble bien avoir changé : Susanyos est désormais le souverain absolu qui ne supporte plus — même pas dans le récit du passé - les conseils ouverts et sincères de sa noblesse ; d'autre part il s'agit de la damnatio memoriae de quelques dignitaires tombés en disgrâce. La tradition manuscrite de la chronique a néanmoins conservé la rédaction non expurgée des chapitres 8 et 9 en question dans quelques mss. Quant au ms. d'Abbadie 42, il porte les traces d'une censure matérielle : les fascicules originaux portant les passages inconvenants sont probablement substitués par de nouveaux, écrits d'une autre main.
Le site de Dankalelo (Ghoubbet al Kharab, République de Djibouti)
Authors: Poisblaud Benoît
Published: September 2009

Résumé : Le golfe du Ghoubbet, au centre de la République de Djibouti, a été le lieu d'une occupation importante par le passé. Le site de Dankalelo en est un exemple caractéristique. La fouille entreprise sur un amas coquillier et une tombe ont permis de confirmer l'occupation temporaire des lieux, la pratique de la pêche, et la fréquentation par des groupes familiaux. Elle a surtout pu mettre en évidence la présence d'une seconde culture.
Grañ à Hayq : un épisode de la conquête de l'Amhara dans la mémoire du Wällo
Authors: Vô Vân David
Published: September 2009

Résumé : le récit du pillage de Däbrä Hayq, tel qu'on peut le lire dans la chronique d'Ahmad Gran, diffère quelque peu de celui qu'en donnent aujourd'hui les moines de l'endroit. L'écart entre les deux versions semble pouvoir s'expliquer par l'influence de 1'" idéologie consensualiste wâllo " repérée par Éloi Ficquet, dont il tend en retour à prouver le bien-fondé. Un fait saillant de l'histoire de l'ancien Amhara se trouve ainsi remodelé par une mentalité s'étant précisée, pour l'essentiel, postérieurement aux guerres de Gran, sans qu'il faille oublier pour autant que l'Amhara (au sens médiéval) et le Wâllo constituent, grosso modo, un seul et même territoire dont l'histoire, en particulier mentale, ne peut comporter de rupture absolue.
Bafflement in Greek Tragedy
Authors: Buxton R.G.A.
Published: September 2009

Bafflementin Greek Tragedy (pp. 41-51)

Dans quelle mesure est-il possible de répondre à la question: «Pourquoi ce qui se produit dans une tragédie grecque se produit-il ?». Dans les Perses, la nature de la causalité dramatique est relativement claire. Dans les Trachiniennes, l'explication de la tragédie est plus complexe. Mais dans certains cas -par exemple pour certaines scènes d'Agamemnon et des Bacchantes et pour la totalité d'une pièce comme Héraclès- les arguments qui permettaient de décider pourquoi les événements se produisent sont soit insuffisants, soit contradictoires. En ce cas la réponse la plus honnête au problème de la causalité consiste à prendre acte de l'aporie. C'est peut-être une qualité particulièrement euripidéenne que de déconcerter de la sorte. Et cela pourrait expliquer pourquoi Euripide était dans l'Antiquité perçu comme un ergoteur.
Odysseia or Penelopeia ? [An assessment of Penelope's character and position in the Odyssey]
Authors: Karakantza E. D.
Published: September 2009

Odysseia or Penelopeia ? (pp. 161-179)

La reine d'Ithaque, à l'encontre des idées reçues qui la veulent immobile dans le palais et à la merci des instincts erotiques des «fiancés», est un personnage actif et habile qui manipule les hommes qui l'assiègent, au moyen de ses charmes erotiques. C'est la femme qui a dirigé les affaires du palais durant l'absence d'Ulysse, et qui a pour longtemps trompé les jeunes gens qui la désiraient grâce à la trouvaille du suaire de Laërce. Faisant preuve de son intelligence, Pénélope désarme ses assaillants en excitant leurs sens et leur imagination, tout en restant pure et inaccessible.

Le titre Penelopeia est d'ailleurs indirectement suggéré par le défunt Agamemnon au chant XXIV de l'Odyssée, quand il déclare que le kleos de la reine deviendra un chant immortel qui la glorifiera pour toujours.
Tours à noyau chemisé de Syrie du Sud
Authors: Braemer Frank , Dentzer J.-M. , Kalos Michael , Tondon Ph.
Published: September 2009

In the Publications of the Princeton University Archaeological Expeditions to Syria in 1904-5 and 1909 (Leyden) 1919 IIA, p. 123, 432, H.C. Butler described two tower-like structures (Safiyeh and Dammet al- 'Aliyyah) which he finds very archaic, almost prehistoric. Recent French explorations in southern Syria discovered six other constructions which belong to the same series. They have at least two storeys and consist of an independent carefully built central core, reinforced by a shell built around it during the same construction phase. An entrance at the base gives access to a staircase climbing to the top of the tower. Without excavations, neither the date nor the function of these structures can be ascertained. They are built on a high spot at the limits of a settlement, providing a view across a desert landscape from where one could expect hostile incursions. Are these watch and defence towers or places of worship like monumental altars? Five of these constructions are indeed standing near a sanctuary.
C-Reactive Protein Gene Polymorphisms in Disease Susceptibility and Clinical Manifestations of Korean Systemic Lupus Erythematosus
Authors: KIM HYOUN-AH , CHUN HYE-YOUNG , KIM SEUNG-HYUN , PARK HAE-SIM , SUH CHANG-HEE
Published: September 2009

Objective.

C-reactive protein (CRP) is a sensitive marker of inflammation. It is hypothesized that polymorphism of CRP gene contributes to susceptibility to systemic lupus erythematosus (SLE). We tested this hypothesis by identifying CRP gene polymorphisms in Korean patients with SLE.

Methods.

Approximately 1.5 kb of CRP promoter region was screened for single nucleotide polymorphism (SNP) using direct sequencing and 3 SNP in CRP exons by restriction fragment length polymorphism. The basal levels of CRP were measured by immunoturbidimetry. The effect of −390 C>A or T polymorphism on the promoter activity was analyzed by luciferase reporter assay in Hep3B cells.

Results.

Allele frequency at polymorphisms within CRP promoter and exon in our Korean patients with SLE differed from that of Caucasians. The A allele was a major allele at position 2043 in Korean SLE patients, whereas G is a major allele in Caucasian SLE. Our SLE patients had minor allele in the −390 polymorphism more frequently versus controls (p = 0.033). CRP 1185 polymorphism was associated with thrombocytopenia (p = 0.043). The basal levels of CRP were significantly higher in individuals who had minor allele in −390 and 2043 polymorphisms (p = 0.03. p = 0.024, respectively). Promoter-reporter construct carrying the −390 A or T allele displayed significantly higher promoter activity than that with the −390 C allele (p < 0.001).

Conclusion.

CRP gene −390 polymorphism plays a role in disease susceptibility of SLE through regulation of serum CRP level. Our results suggest that elevated basal CRP level may be important in the pathogenesis of SLE, even though CRP responsiveness to noninfectious inflammation of SLE is decreased.
Epstein–Barr Virus
Authors: Young Lawrence S , Sung Nancy S , Pagano Joseph S
Published: September 2009

Epstein–Barr virus

(EBV) is a ubiquitous herpesvirus which is implicated in the aetiology of different lymphoid and epithelial malignancies. The virus has a unique ability to transform resting B lymphocytes

in vitro

by expressing a set of latent genes and subsets of these same genes are present in EBV‐associated tumours. EBV exploits the physiology of normal B‐cell differentiation to persist within the memory B cell pool of the immunocompetent host and strong cell‐mediated T‐cell responses are important in controlling EBV infection. Immunosuppressed transplant recipients and human immunodeficiency virus (HIV)‐infected individuals are at increased risk of developing EBV‐transformed B‐cell proliferations which often present as monoclonal non‐Hodgkin lymphomas. The major EBV‐associated tumours (Burkitt lymphoma, Hodgkin lymphoma and nasopharyngeal carcinoma) show restricted forms of virus latent gene expression reflecting a more complex pathogenesis that involves additional cofactors. A number of pharmacological and immunotherapeutic approaches are being developed to treat or prevent these EBV‐associated tumours.

Key concepts

Epstein–Barr virus
(EBV) infection is implicated in the aetiology of several different lymphoid and epithelial malignancies.

EBV exploits the physiology of normal B‐cell differentiation to persist within the memory B cell pool of the immunocompetent host.

EBV‐encoded latent genes induce B‐cell transformation
in vitro
by altering cellular gene transcription and constitutively activating key cell signalling pathways.

Immunosuppressed transplant patients are at risk of developing EBV‐transformed B‐cell proliferations presenting as B‐cell lymphomas.

Other EBV‐associated tumours display more restricted forms of latent gene expression, reflecting more complex pathogenesis involving additional cofactors.

Pharmacological and immunotherapeutic approaches are being developed to treat or prevent EBV‐associated tumours.
Model NOx Storage Materials at Realistic NO2 Pressures
Authors: Desikusumastuti Aine , Schernich Stefan , Happel Markus , Sobota Marek , Laurin Mathias , Libuda Jörg
Published: September 2009

The interaction of NO2 with single‐crystal‐based model NOx storage materials, consisting of barium aluminate nanoparticles on Al2O3/NiAl(110), are investigated by time‐resolved infrared reflection absorption spectroscopy (TR‐IRAS) at realistic NO2 partial pressures up to 1.75 mbar. The data is compared to spectra obtained under ultrahigh vacuum (UHV) conditions on the same model system. At 300 K, the NO2 uptake at pressures around 1 mbar proceeds through rapid initial formation of surface nitrites and nitrates, similar to that under UHV conditions. The vibrational spectra of the surface species formed at realistic NO2 pressures are comparable to those for species formed under UHV conditions. Beyond the formation of surface species, the formation of bulk nitrates occurs, but is kinetically strongly hindered. At a very low rate, the formation of a disordered barium bulk nitrate is detected. At 500 K, this kinetic hindrance is overcome and the available Ba2+ is quantitatively converted to bulk Ba(NO3)2. The IRAS spectrum of these Ba(NO3)2 particles differs characteristically from those obtained for nitrate multilayers formed upon incomplete conversion under UHV conditions. In addition to the formation of bulk Ba(NO3)2, a more weakly bound disordered nitrate species is formed. This species gives rise to a dynamic NO2 uptake and release well below the decomposition temperature of bulk Ba(NO3)2. The experiments show that model studies under UHV conditions mainly provide information on the initial reaction mechanism, whereas the observation of actual bulk NOx storage phases requires experiments at realistic temperatures and pressures.
Oxide layer dissolution in Si/SiOx/Si wafer bonded structures
Authors: Zakharov N. , Pippel E. , Werner P. , Vdovin V. , Gösele U.
Published: September 2009

The evolution of the interfaces of hydrophilic‐bonded Si wafers and the corresponding low‐angle twist boundary have been analysed in relation to thermal annealing and their relative crystallographic orientation. Two orientation relationships were investigated: Si<001>/Si<001> and Si<001>/Si<110>, where the interfaces are seperated by thin native SiO2 layers. The interfaces were analysed by TEM and STEM/EELS. It is found that the decomposition rate of the intermediate oxide layer and the formation of a Si(Si bonded interface depend very much on the lattice mismatch and on the twist angle. The velocity of the dissolution of the thin oxide layers and the formation of Si(Si bonds at the bonding interface depend on the orientation relations of the corresponding wafers. The processes of interface fusion and the dissolution of oxide layer are discussed. (© 2009 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Biomass into Chemicals: Aerobic Oxidation of 5‐Hydroxymethyl‐2‐furfural into 2,5‐Furandicarboxylic Acid with Gold Nanoparticle Catalysts
Authors: Casanova Onofre , Iborra Sara , Corma Avelino
Published: September 2009

5‐hydroxymethyl‐2‐furfural is selectively converted into 2,5‐furandicarboxylic acid (99 mol % yield) in water, under mild conditions (65–130 °C, 10 bar air) with gold nanoparticles supported on nanoparticulate ceria (Au‐CeO2) and on titania (Au‐TiO2); the former being more active and selective. A reaction mechanism is established and the rate‐limiting step of the reaction is the alcohol oxidation of 5‐hydroxymethyl‐2‐furancarboxylic acid into 2,5‐furandicarboxylic acid. The effects of pressure, temperature, substrate‐to‐catalyst ratio, and amount of base are studied to find the most suitable reaction conditions. The absence of metal leaching is verified by chemical analysis of the reaction solution and by confirming that the reaction does not occur after catalyst removal by filtration in hot water. Substrate degradation is strongly diminished and the catalyst life increased by performing the reaction in two temperature steps.
Summary of ‘Intranasal corticosteroids for nasal airway obstruction in children with moderate to severe adenoidal hypertrophy’, including tables of key findings and quality of included trials
Authors: Zhang L. , Mendoza‐Sassi R. A. , César J. A. , Chadha N. K. , van Dalen E. C. , Kremer L. C. M.
Published: September 2009

This is a summary, including tables of key findings and quality of included trials, of a Cochrane review, published in this issue of EBCH, first published as: Zhang L, Mendoza‐Sassi RA, César JA, Chadha NK. Intranasal corticosteroids for nasal airway obstruction in children with moderate to severe adenoidal hypertrophy. Cochrane Database of Systematic Reviews 2008, Issue 3. Art. Mp.:CD006286. DOI: 10.1002/14651858.CD006286.pub2.

Further information for this Cochrane review is available in this issue of EBCH in the accompanying Commentary. Copyright © 2009 The Cochrane Collaboration. Published by John Wiley & Sons, Ltd. The Cochrane Collaboration
Summary of ‘Acylovir for treating primary herpetic gingivostomatitis’, including tables of key findings and quality of included trials
Authors: Nasser M. , Fedorowicz Z. , Khoshnevisan M. H. , Shahiri Tabarestani M. , van Dalen E. C. , Kremer L. C. M.
Published: September 2009

This is a summary, including tables of key findings and quality of included trials, of a Cochrane review, published in this issue of EBCH, first published as: Nasser M, Fedorowicz Z, Khoshnevisan MH, Shahiri Tabarestani M. Acyclovir for treating primary herpetic gingivostomatitis. Cochrane Database of Systematic Reviews 2008, Issue 4. Art. No.: CD006700. DOI:10.1002/14651858.CD006700.pub2.

Further information for this Cochrane review is available in this issue of EBCH in the accompanying Commentary. Copyright © 2009 The Cochrane Collaboration. Published by John Wiley & Sons, Ltd. The Cochrane Collaboration
An application of the successive shortest path algorithm to manage power in multi‐agent system based active networks
Authors: Nguyen Phuong H. , Kling Wil L. , Myrzik Johanna M.A.
Published: September 2009

In order to handle a high penetration of distributed generation (DG), the existing passive distribution systems need to become more active. In the so‐called active network (AN), power flow management has developed to cope with bidirectional power flow and the intermittence of DGs. This paper proposes a method to better manage active power flows based on graph theory application and multi‐agent system (MAS). While the power system is represented as a directed graph, the optimal power flow (OPF) is understood as a minimum cost flow problem that can be solved by the successive shortest path algorithm. The algorithm is implemented in a distributed way and is supported by MAS. Simulations using a five sub‐areas network show that the method is able to reach the optimal operation state while restraining power flows within defined bounds. Furthermore, the method can also response changes in power generation cost, network configuration and load demand increase. Copyright © 2009 John Wiley & Sons, Ltd.