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Various Modes (various + mode)
Selected AbstractsHysteretic models that incorporate strength and stiffness deteriorationEARTHQUAKE ENGINEERING AND STRUCTURAL DYNAMICS, Issue 12 2005Luis F. Ibarra Abstract This paper presents the description, calibration and application of relatively simple hysteretic models that include strength and stiffness deterioration properties, features that are critical for demand predictions as a structural system approaches collapse. Three of the basic hysteretic models used in seismic demand evaluation are modified to include deterioration properties: bilinear, peak-oriented, and pinching. The modified models include most of the sources of deterioration: i.e. various modes of cyclic deterioration and softening of the post-yielding stiffness, and also account for a residual strength after deterioration. The models incorporate an energy-based deterioration parameter that controls four cyclic deterioration modes: basic strength, post-capping strength, unloading stiffness, and accelerated reloading stiffness deterioration. Calibration of the hysteretic models on steel, plywood, and reinforced-concrete components demonstrates that the proposed models are capable of simulating the main characteristics that influence deterioration. An application of a peak-oriented deterioration model in the seismic evaluation of single-degree-of-freedom (SDOF) systems is illustrated. The advantages of using deteriorating hysteretic models for obtaining the response of highly inelastic systems are discussed. Copyright © 2005 John Wiley & Sons, Ltd. [source] Fracture and fatigue study of unidirectional glass/epoxy laminate under different mode of loadingFATIGUE & FRACTURE OF ENGINEERING MATERIALS AND STRUCTURES, Issue 5 2010M. KENANE ABSTRACT Interlaminar fracture is the dominant failure mechanism in most advanced composite materials. The delaminating behaviour of materials is quantified in terms of the strain energy release rate,G. In this paper, the experimental measurements of the fatigue delaminating growth for some combinations of energy release rate mode ratio have been carried out on unidirectional glass/epoxy laminates. On this base the constants in the Paris equation have been determined for each GII/GT considered modal ratio. The fatigue threshold strain energy release rate ,,GTth, below which delaminating doesn't occur, were measured. Three type specimens were tested, namely: double cantilever beam (DCB), end-loaded split (ELS) and mixed-mode bending (MMB) under mode I, mode II and mixed-mode (I + II) loading, respectively. Scanning electron microscopy techniques were used to identify the fatigue delamination growth mechanisms and to define the differences between the various modes of fracture. [source] Phosphorylation of NF-,B proteins by cyclic GMP-dependent kinaseFEBS JOURNAL, Issue 10 2003A noncanonical pathway to NF-, B activation The transcription factor NF-,B is activated in cellular stress responses. This requires rapid regulation of its function, which is accomplished, in part, by various modes of phosphorylation. Even though diverse DNA binding subunits of NF-,B proteins may transactivate from distinct recognition sequences, the differential regulation of transcription from the large number of NF-,B responsive sites in various gene promoters and enhancers has been incompletely understood. The cyclic GMP-dependent kinase (PKG) is an important mediator of signal transduction that may induce gene expression through cAMP response element binding protein (CREB) and through other, yet undefined, mechanisms. We have previously characterized a signal transduction pathway that leads to activation-induced cell death in T-lymphocytes and involves the activation of PKG. Here we demonstrate that the NF-,B proteins p65, p49 (also called p52), and p50 are specific substrates for this kinase. PKG dose-dependently increases the transactivating activity of p65 from the NF-,B consensus sequence. It also mediates dose-dependently an increase in transcriptional activity by p49 or p50 from a unique CCAAT/enhance binding protein (C/EBP)-associated NF-,B site, but not from the consensus site. Phosphorylation of p65, p50, or p49 does not alter their subcellular distribution. Because the release of cytosolic p65/p50 heterodimers into the nucleus is by itself insufficient to differentiate all the numerous NF-,B promoter sequences, phosphorylation of the DNA-binding subunits reveals a form of differential regulation of NF-,B activity and it implies a novel pathway for PKG-induced gene transcription. These observations may bear on mechanisms of programmed cell death in T-lymphocytes. They may also be relevant to ongoing efforts to induce cancer cell apoptosis through activation of PKG. [source] Combined endovascular and surgical treatment of head and neck paragangliomas,A team approach,HEAD & NECK: JOURNAL FOR THE SCIENCES & SPECIALTIES OF THE HEAD AND NECK, Issue 5 2002Mark S. Persky MD Abstract Background Paragangliomas are highly vascular tumors of neural crest origin that involve the walls of blood vessels or specific nerves within the head and neck. They may be multicentric, and they are rarely malignant. Surgery is the preferred treatment, and these tumors frequently extend to the skull base. There has been controversy concerning the role of preoperative angiography and embolization of these tumors and the benefits that these procedures offer in the evaluation and management of paragangliomas. Methods Forty-seven patients with 53 paragangliomas were treated from the period of 1990,2000. Initial evaluation usually included CT and/or MRI. All patients underwent bilateral carotid angiography, embolization of the tumor nidus, and cerebral angiography to define the patency of the circle of Willis. Carotid occlusion studies were performed with the patient under neuroleptic anesthesia when indicated. The tumors were excised within 48 hours of embolization. Results Carotid body tumors represented the most common paraganglioma, accounting for 28 tumors (53%). All patients underwent angiography and embolization with six patients (13%), demonstrating complications (three of these patients had embolized tumor involving the affected nerves). Cerebral angiography was performed in 28 patients, and 5 of these patients underwent and tolerated carotid occlusion studies. The range of mean blood loss according to tumor type was 450 to 517 mL. Postoperative cranial nerve dysfunction depended on the tumor type resected. Carotid body tumor surgery frequently required sympathetic chain resection (21%), with jugular and vagal paraganglioma removal frequently resulting in lower cranial nerve resection. These patients required various modes of postoperative rehabilitation, especially vocal cord medialization and swallowing therapy. Conclusions The combined endovascular and surgical treatment of paragangliomas is acceptably safe and effective for treating these highly vascular neoplasms. Adequate resection may often require sacrifice of one or more cranial nerves, and appropriate rehabilitation is important in the treatment regimen. © 2002 Wiley Periodicals, Inc. [source] Bifurcation and instability modelling by a multimechanism elasto-plastic modelINTERNATIONAL JOURNAL FOR NUMERICAL AND ANALYTICAL METHODS IN GEOMECHANICS, Issue 5 2008Kamel Hamadi Abstract The bifurcation and instability conditions in geomechanics are closely related to the elasto-plastic behaviour. In this paper the potential of a multimechanism elasto-plastic model to predict various modes of failure is examined. First, a brief overview for the essential aspects of the constitutive model and the development of the elasto-plastic constitutive matrix for this model are presented. Then, numerical simulations of different drained and undrained paths in the axisymmetric and plane-strain conditions for the Hostun sand are illustrated. These examples confirm the capacity of the model to reproduce instability and strain localization phenomena. The obtained response is in agreement with experimental observations, theoretical developments and numerical analyses existing in the literature. Copyright © 2007 John Wiley & Sons, Ltd. [source] Numerical simulation on joint motion process of various modes of caisson breakwater under wave excitationINTERNATIONAL JOURNAL FOR NUMERICAL METHODS IN BIOMEDICAL ENGINEERING, Issue 6 2006Wang Yuan-Zhan Abstract A caisson breakwater may experience various modes of motions under wave action. The elementary motion modes are classified into two categories, i.e. the horizontal and rotational vibration coupled motion and the horizontal slide and rotational vibration coupled motion. The motion modes of caisson will transform from one to another depending on the wave forces and the motion behaviours of a caisson. The numerical models of the two motion modes of caisson are developed, the numerical simulation procedure for joint motion process of the two modes of caisson breakwater under wave excitation is presented and tested by a physical model experiment. It is concluded that the simulation procedure is reliable and can be applied to the dynamic stability analysis of caisson breakwaters. Copyright © 2005 John Wiley & Sons, Ltd. [source] Forest progression modes in littoral Congo, Central Atlantic AfricaJOURNAL OF BIOGEOGRAPHY, Issue 9 2004Charly Favier Abstract Aim, To understand the persistence of a forest,savanna mosaic in places where rainfall data suggest that forest take-over should take place. To study the various modes of forest encroachment, and the role of human activities to hamper it. Location, Data were collected on several forest,savanna ecotones in the coastal region of the Republic of Congo. The sites were chosen to illustrate the differing principal modes of forest expansion, corresponding to different levels of anthropic pressure. Methods, The study sites were situated on five transects perpendicular to the ecotone (total sampled area: 1.7 ha) and 10 forest clumps in savanna (with diameters from 3 to 20 m). Along the transects botanical identification, diameter measurement and cartography were performed, while leaf area index was measured at a high resolution (every metre) along two of them. Collected data were analysed using a continuous quantification approach, which is much more useful than classical quadrat analysis. Time calibration of progression rates was performed using a simple model of the growth of the characteristic pioneer species, Aucoumea klaineana. Results, The two main different modes are reflected in different successional patterns. The edge diffusion is slow (its rate is evaluated to c. 1 m year,1) and is characterized by a progressive increase in large-diameter tree density and shade-tolerant tree density away from the ecotone. Conversely, savanna to forest phase transition by coalescence of clumps exhibits high tree density remnants distributed in established forest. The composition of these remnants is compatible with that of the forest clumps in savannas. Main conclusions, Three functional groups of pioneer trees are distinguished: some occupy the edge (edge pioneer), others establish clumps of forest in savanna (clump pioneers) and the longer-living A. klaineana ensures the transition to ,mature' forest. The two different observed patterns (linear edge progression and clump coalescence) can be understood with the use of a model of forest,savanna dynamics, ,FORSAT'. The two control parameters are the annual rainfall and the frequency of man-made fires in each savanna. In particular, an increase in the fire frequency can lead to a shift from the coalescence regime to the edge progression one. [source] Law, health and the European UnionLEGAL STUDIES, Issue 2 2005Tamara K Hervey How does the European Union (EU) affect health law in its member states.? Having defined ,health law', this article takes a multilevel governance perspective of the EU und its legal order, aid considers, through selected examples, the various modes of governance used by the EU applicable in the health law field. The article presents N spectrum of the different types of effect that the EU has on health law: strong effect from health-specific measures; strong effect from general measures; marginal effect; slow convergence effect; little prospect for effect. [source] Acute kidney injury and renal replacement therapy in the intensive care unitNURSING IN CRITICAL CARE, Issue 4 2009Peter Faber Abstract Background:, Renal replacement therapy (RRT) is now offered as a routine treatment in most intensive care units (ICU) in the UK for patients suffering from acute kidney injury (AKI). It is important for all ICU staff to understand the underlying principles of the available therapeutic options and the possible complications thereof. Aims and objectives:, The objective of this review was to provide an accessible theoretical and practical update on the management of RRT. In addition to a detailed discussion of the underlying principles and indications for the various modes of RRT, we will discuss the assessment of kidney function, possible complications and anticoagulation during RRT, following a review of the current literature. Search strategies:, Pubmed, Medline and the Cumulative Index to Nursing and Allied Health Literature were searched using the keywords renal function, RRT, dialysis, renal failure kidney injury, together with intensive care, intensive therapy and critical care. We included only studies published in English from 1998 to 2008 and from these identified and included additional publications. The 12 most relevant publications are referenced in this review. Conclusion:, AKI is associated with increased mortality in ICU, and RRT should be considered early in the disease process. Continuous haemofiltration is the most common modality of treatment in this group of patients, and a detailed knowledge of the management of such patients is required. [source] Phonon polariton modes in porous III,V semiconductorsPHYSICA STATUS SOLIDI (B) BASIC SOLID STATE PHYSICS, Issue 12 2005K. S. Joseph Wilson Abstract The phonon polariton modes in the bulk porous III,V semiconductor materials like GaP and GaAs are investigated for different porosity values. Their behavior under an external hydrostatic pressure is also studied. The frequencies of the various modes shift to higher values. The model has been extended to the case of self assembled GaP quantum dots (QDOTs) in GaAs matrix. (© 2005 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) [source] Between memory and destiny: Repetition,THE INTERNATIONAL JOURNAL OF PSYCHOANALYSIS, Issue 2 2007NORBERTO CARLOS MARUCCO This essay focuses mainly on the topic of repetition (agieren),on its metapsychological, clinical, and technical conceptions. It contains a core problem, that is, the question of the represented, the nonrepresented, and the unrepresentable in the psyche. This problem, in turn, brings to light the dialectical relation between drive and object and its specific articulation with the traumatic. The author attributes special significance to its clinical expression as ,destiny'. He points out a shift in the theory of the cure from recollection and the unveiling of unconscious desire, to the possibility of understanding ,pure' repetition, which would constitute the very essence of the drive. The author highlights three types of repetition, namely, ,representative' (oedipal) repetition, the repetition of the ,nonrepresented' (narcissistic), which may gain representation, and that of the ,unrepresentable' (sensory impressions, ,lived experiences from primal times,',prelinguistic signifiers,',ungovernable mnemic traces'). The concept-the metaphor-drive embryo brings the author close to the question of the archaic in psychoanalysis, where the repetition in the act would express itself. ,Another unconscious' would zealously conceal the entombed (verschüttet) that we are not yet able to describe-the ,innermost' rather than the ,buried' (untergegangen) or the ,annihilated' (zugrunde gegangen)-through a mechanism whose way of expression is repetition in the act. With ,Constructions in analysis' as its starting point, this paper suggests a different technical implementation from that of the Freudian construction; its main material is what emerges in the present of the transference as the repetition of ,something' lacking as history. The memory of the analytic process offers a historical diachrony whereby a temporality freed from repetition and utterly unique might unfold in the analysis. This diachrony would no longer be the historical reconstruction of material truth, but the construction of something new. The author briefly introduces some aspects of his conception of the psyche and of therapeutic work in terms of what he has designated as psychic zones. These zones are associated with various modes of becoming unconscious, and they coexist with different degrees of prevalence according to the psychopathology. Yet each of them will emerge with unique features in different moments of every analysis, determining both the analyst's positions and the very conditions of the analytic field. The zone of the death drive and of repetition is at the center of this essay. ,Pure' repetition expresses a time halted by the constant reiteration of an atemporal present. In this case, the ,royal road' for the expression of ,that' unconscious will be the act. The analyst's presence and his own drive wager will be pivotal to provide a last attempt at binding that will allow the creation of the lost ,psychic fabric' and the construction, in a conjectural way, of some sort of ,history' that may unravel the entombed (verschüttet) elements that, in these patients' case, come to the surface in the act. The analysand's ,pure' repetition touches, resonates with something of the new unconscious of the analyst. All of this leads the author to underline once again the value of the analyst's self-analysis and reanalysis in searching for connections and especially in differentiating between what belongs to the analyst and what belongs to the analysand. A certain degree of unbinding ensures the preservation of something ungraspable that protects one from the other's appropriation. [source] Import Competition and Employment in Japan: Plant Startup, Shutdown and Product ChangesTHE JAPANESE ECONOMIC REVIEW, Issue 2 2004Eiichi Tomiura This paper examines the relationship between import competition and employment during and after the recent Bubble period in Japan. Gross job flow data are combined with import data for 334 four-digit manufacturing industries. The estimates demonstrate that various modes of employment adjustment respond differently to changes in import prices. Job creation/destruction associated with plant startups/shutdowns was significantly sens-itive to import competition. Among plants continuously operating, job creation during the Bubble boom by plants that altered their product mix across industries was responsive to import price fluctuations, while job flows at plants that remained within the same industries were not. [source] The Sources and Fortunes of Piranesi's Archaeological IllustrationsART HISTORY, Issue 4 2002Susan M. Dixon Susan M. Dixon earned her doctorate from Cornell University in 1991 with a dissertation on the archaeological publications of Giovanni Battista Piranesi. She studies the history of pre,scientific archaeology, from Pirro Ligorio to Piranesi, with a particular focus on illustration as a means to convey historical knowledge. She has published on this subject in a variety of venues, and is beginning a book,length manuscript on the subject. In 1995,96, she was awarded a J. Paul Getty post,doctoral fellowship to study the Accademia degli Arcadi, a society founded in 1690 primarily to restore good taste in literature, and its successes and failures in bringing about the reform of Italian society and architecture. She has written a book entitled The Bosco Parrasio: Performance and Perfectibility in the Garden of the Arcadians, which focuses on their garden meeting place as a breeding ground for a utopian society. Dr Dixon teaches art history at the University of Tulsa in Oklahoma. Giovanni Battista Piranesi (1720,1778) developed a way of representing the archaeological past by using the multi,informational image, an engraved illustration which appears to be a composite of various drawings, on various surfaces, and employing various modes of representation, scale and detail. The cartographic tradition, particularly maps from sixteenth,century Europe, offer a precedent for this type of illustration. Piranesi found theoretical underpinnings for it in contemporary discussions about the workings of the human memory, which was identified as a viable tool for those pursuing historical knowledge. His illustrations make visible the processes of memory on an assemblage of archaeological information, and they were a means to historical reconstruction. Archaeologists of the generation after Piranesi did not use the multi,informational image as the science of archaeology underwent a sea change at the end of the century. However, some compilers of travel literature, in particular Jean,Laurent,Pierre HoÃ,el, author and illustrator of Voyage pittoresque des isles de Sicile, de Malte, et de Lipari, found the format suitable to their purposes. Like Piranesi's, Hoüel's multi,informational images reveal the hand of the artist on the information he had diligently collected and ordered; Hoüel's picturesque illustrations of the southern Italian islands' people and places are self,consciously subjective. The format also makes apparent what was so appealing to many a voyager ,the apparent survival of the past in the culture of the present. [source] Thyroid hormones and their effects: a new perspectiveBIOLOGICAL REVIEWS, Issue 4 2000A. J. HULBERT ABSTRACT The thyroid hormones are very hydrophobic and those that exhibit biological activity are 3,,5,,3,5-Ltetraiodothyronine (T4), 3,,5,3-L-triiodothyronine (T3), 3,,5,,3-L-triiodothyronine (rT3) and 3,5,-Ldiiodothyronine (3,5-T2). At physiological pH, dissociation of the phenolic -OH group of these iodothyronines is an important determinant of their physical chemistry that impacts on their biological effects. When non-ionized these iodothyronines are strongly amphipathic. It is proposed that iodothyronines are normal constituents of biological membranes in vertebrates. In plasma of adult vertebrates, unbound T4 and T3 are regulated in the picomolar range whilst protein-bound T4 and T3 are maintained in the nanomolar range. The function of thyroid-hormone-binding plasma proteins is to ensure an even distribution throughout the body. Various iodothyronines are produced by three types of membrane-bound cellular deiodinase enzyme systems in vertebrates. The distribution of deiodinases varies between tissues and each has a distinct developmental profile. Thyroid hormones have many effects in vertebrates. It is proposed that there are several modes of action of these hormones.(1) The nuclear receptor mode is especially important in the thyroid hormone axis that controls plasma and cellular levels of these hormones.(2) These hormones are strongly associated with membranes in tissues and normally rigidify these membranes.(3) They also affect the acyl composition of membrane bilayers and it is suggested that this is due to the cells responding to thyroid-hormone-induced membrane rigidification. Both their immediate effects on the physical state of membranes and the consequent changes in membrane composition result in several other thyroid hormone effects. Effects on metabolism may be due primarily to membrane acyl changes. There are other actions of thyroid hormones involving membrane receptors and influences on cellular interactions with the extracellular matrix. The effects of thyroid hormones are reviewed and appear to be combinations of these various modes of action. During development, vertebrates show a surge in T4 and other thyroid hormones, as well as distinctive profiles in the appearance of the deiodinase enzymes and nuclear receptors. Evidence from the use of analogues supports multiple modes of action. Re-examination of data from the early 1960s supports a membrane action. Findings from receptor ,knockout' mice supports an important role for receptors in the development of the thyroid axis. These iodothyronines may be better thought of as ,vitamone' -like molecules than traditional hormonal messengers. [source] | ||||||||||||||||