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Successive Phases (successive + phase)
Selected AbstractsLarge displacement behaviour of a structural model with foundation uplift under impulsive and earthquake excitationsEARTHQUAKE ENGINEERING AND STRUCTURAL DYNAMICS, Issue 3 2003Giuseppe Oliveto Abstract This paper considers the dynamical behaviour of a structural model with foundation uplift. The equations of motion of the system considered are derived for large displacements thus allowing for the eventual overturning of the system. The transition conditions between successive phases of motion, derived in terms of the specific Lagrangian co-ordinates used in the formulation of the equations of motion, present innovative aspects which resolve some previously inexplicable behaviour in the structural response reported in the literature. The dynamical behaviour of the model is considered under impulsive and long-duration ground motions. The minimum horizontal acceleration impulses for the uplift and the overturning of the system are evaluated in analytical form. The sensitivity of the model to uplifting and to overturning under impulsive excitations is established as a function of few significant structural parameters. Numerical applications have been performed changing either the structural parameters or the loading parameter, in order to analyse several dynamical behaviours and also to validate the analytical results. For earthquake ground motions the results, reported in the form of response spectra, show that linearized models generally underestimate, sometimes significantly, the structural response. Copyright © 2003 John Wiley & Sons, Ltd. [source] Stepping from Illegality to Legality and Advancing towards Integration: The Case of Immigrants in Greece,INTERNATIONAL MIGRATION REVIEW, Issue 4 2005Nicholas P. Glytsos This paper highlights how the social and economic situation of immigrants changes after their formal legalization and discusses what they nave to go through for their complete integration. Legalization can hardly solve the problem of immigrant employment, nor can it pull all immigrants out of the underground labor market and integrate them into the Greek economy ana society. The process towards complete integration is painful and involves a series of successive phases of various durations. During this period, apart from economic conditions, various institutional and cultural factors can hinder or delay integration. With respect to economic integration, immigrants seem to fare rather well. Their official unemployment rate is only slightly higher than the Greek unemployment rate, the two rates converging over time. This suggests increasing relative opportunities for immigrant employment, precarious or stable as it might be. Immigrant jobs come as a result of their flexible adjustment to the needs of the labor market - official or underground - compared to the inflexibility in the supply of Greek workers, due to labor mismatches and relatively high reservation wages. Wages of immigrants are generally lower, but are approaching the wages of their Greek counterparts. Educated immigrants much more than educated Greeks are forced by the circumstances to exercise jobs not measuring up to their qualifications. [source] Response of bacterial community during bioremediation of an oil-polluted soil,JOURNAL OF APPLIED MICROBIOLOGY, Issue 2 2003M. Zucchi Abstract Aim: To study the response of the bacterial community to bioremediation of a soil with an aged contamination of crude oil. Methods and Results: The bacterial community in laboratory soil columns during a 72-day biostimulation treatment was followed by analysing the number of total cultivable hydrocarbon-degrading bacteria, soil respiratory activity and the 16S,23S rDNA internal transcribed spacer homoduplex heteroduplex polymorphisms (ITS-HHP) of total soil bacterial DNA. ITS-HHP permits an estimate of both length and sequence polymorphism in a 16S,23S rDNA spacer population, using to advantage the homoduplex and heteroduplex fragments that are generated during PCR. The treatment, made by air sparging and biostimulation with a mineral nutrient and surfactant solution, resulted in a 39·5% decrease of the total hydrocarbon content. Within 4 days of treatment onset the bacterial community underwent a first phase of activation that led to a substantial increase in the observable diversity. Subsequently, after a 12-day period of stability, another activation phase was observed with further shifts of the community structure and an increase in the abundance and diversity of catechol-2,3-dioxygenase (C23O) genes. Conclusions: The overall data suggest an important contribution of uncultivable bacteria to the soil bioremediation, since, during the second activation phase, the increases of the respiratory activity, bacterial diversity and C23O gene abundance and diversity were not accompanied by a corresponding increase of the cultivable bacteria number. Significance and Impact of the Study: This study shows that successive phases of activation of bacterial populations occur during a bioremediation treatment of oil-polluted soil. [source] Origin and emplacement of the impact formations at Chicxulub, Mexico, as revealed by the ICDP deep drilling at Yaxcopoil-1 and by numerical modelingMETEORITICS & PLANETARY SCIENCE, Issue 7 2004Dieter Stöffler We present and interpret results of petrographic, mineralogical, and chemical analyses of the 1511 m deep ICDP Yaxcopoil-1 (Yax-1) drill core, with special emphasis on the impactite units. Using numerical model calculations of the formation, excavation, and dynamic modification of the Chicxulub crater, constrained by laboratory data, a model of the origin and emplacement of the impact formations of Yax-1 and of the impact structure as a whole is derived. The lower part of Yax-1 is formed by displaced Cretaceous target rocks (610 m thick), while the upper part comprises six suevite-type allochthonous breccia units (100 m thick). From the texture and composition of these lithological units and from numerical model calculations, we were able to link the seven distinct impact-induced units of Yax-1 to the corresponding successive phases of the crater formation and modification, which are as follows: 1) transient cavity formation including displacement and deposition of Cretaceous "megablocks;" 2) ground surging and mixing of impact melt and lithic clasts at the base of the ejecta curtain and deposition of the lower suevite right after the formation of the transient cavity; 3) deposition of a thin veneer of melt on top of the lower suevite and lateral transport and brecciation of this melt toward the end of the collapse of the transient cavity (brecciated impact melt rock); 4) collapse of the ejecta plume and deposition of fall-back material from the lower part of the ejecta plume to form the middle suevite near the end of the dynamic crater modification; 5) continued collapse of the ejecta plume and deposition of the upper suevite; 6) late phase of the collapse and deposition of the lower sorted suevite after interaction with the inward flowing atmosphere; 7) final phase of fall-back from the highest part of the ejecta plume and settling of melt and solid particles through the reestablished atmosphere to form the upper sorted suevite; and 8) return of the ocean into the crater after some time and minor reworking of the uppermost suevite under aquatic conditions. Our results are compatible with: a) 180 km and 100 km for the diameters of the final crater and the transient cavity of Chicxulub, respectively, as previously proposed by several authors, and b) the interpretation of Chicxulub as a peak-ring impact basin that is at the transition to a multi-ring basin. [source] An additional phase in PCr use during sustained isometric exercise at 30% MVC in the tibialis anterior muscleNMR IN BIOMEDICINE, Issue 4 2002C. J. Houtman Abstract The occurrence of an abrupt acceleration in phosphocreatine hydrolysis in the tibial anterior muscle during the last part of a sustained isometric exercise at 30% maximal voluntary contraction until fatigue is demonstrated in seven out of eight healthy subjects by applying in vivo31P NMR spectroscopy at 1.5,T field strength. This additional third phase in PCr hydrolysis, is preceded by a common biphasic pattern (first fast then slow) in PCr use. The NMR spectra, as localized by a surface coil and improved by proton irradiation, were collected at a time resolution of 16 s. Mean rates of PCr hydrolysis during exercise were ,0.44,±,0.19% s,1, ,0.07,±,0.04% s,1, and ,0.29,±,0.10% s,1 for the three successive phases. The increased rate of PCr hydrolysis, and also the loss of fine force control evident in the force records are consistent with increased involvement of large, fast-fatiguable units later in the contraction. Copyright © 2002 John Wiley & Sons, Ltd. [source] Georg Brandes between Politics and the Political,ORBIS LITERARUM, Issue 3 2007Poul Houe While conventional politics played a part in Georg Brandes's critical practice that has received ample scholarly attention, his appropriation of the political as an ontological concern with ,,the very way society is instituted'' (to cite Chantal Mouffe) has gone quite unheeded in studies of his writings. Yet I consider this dimension to be indispensable for Brandes's ability to articulate his most antagonistic leanings within democratic forms of discourse. Thus he reconciled an acceptance of concensus with the need for dissent. My essay interrogates three areas that were strongly on Brandes's mind during successive phases of his mature life: the Danish constitutional struggle of the 1880s, the so-called Dreyfus affair around 1900, and later the repression of minorities, foreign lands, and anti-war movements in Europe. In each area he makes an uncompromising stand within the boundary of civil, intellectual discourse. Such antagonism channeled into democratic expresssion is what Mouffe calls agonism, and as Brandes expresses antagonism at its most agonizing, I argue that he displays the political in a nutshell for a post-political era to behold. [source] Physiological and behavioral effects of social introduction on adult male rhesus macaquesAMERICAN JOURNAL OF PRIMATOLOGY, Issue 6 2008Lara A. Doyle Abstract Pair housing of laboratory macaques is widely considered to lead to positive changes in well-being, yet the process of introduction is viewed as potentially stressful and risk-prone. Behavioral and physiological data were collected on eight adult male rhesus macaques before, during, and after the process of introduction, in order to measure the initial stress of introduction as well as long-term changes in well-being. Socially experienced subjects, all implanted with biotelemetry devices, were studied in five successive phases: baseline (singly housed), 1 day each of protected contact and full contact introduction, post-introduction (1,3 weeks after introduction), and settled pairs (,20 weeks after introduction). One hundred and seventy-six hours of behavioral data and 672,hr of heart rate data were analyzed. Fecal cortisol was also measured for the baseline, post-introduction, and settled pair phases. All introductions were successful and subjects showed no physiological or behavioral signs of stress, such as increased heart rate, abnormal behavior, or psychological indices of distress (depressive/anxiety-related behavior). Agonism was minimal throughout the introduction process and over the subsequent months; only one wound was incurred over the course of the study. Levels of abnormal behaviors, psychological indices of distress, locomotion, inactivity, and affiliation showed improvements within several weeks after introduction; these changes were still present 5,9 months later for the latter two categories. Heart rates during introduction fell significantly in the settled pair phase, and also varied predictably with time of day. Fecal cortisol levels were lower in settled pairs than in single housing. The fact that reductions in abnormal behavior did not persist over the long term may have been confounded by increasing duration of time spent caged. The results of this study may be of practical use for designing and monitoring social introductions and suggest that managers should not dismiss the feasibility of successful pairing of adult male rhesus macaques. Am. J. Primatol. 70:542,550, 2008. © 2008 Wiley-Liss, Inc. [source] Phylogeography of spiny mice (genus Acomys, Rodentia: Muridae) from the south-western margin of the Sahara with taxonomic implicationsBIOLOGICAL JOURNAL OF THE LINNEAN SOCIETY, Issue 1 2009VIOLAINE NICOLAS The present study aims to depict the overall pattern of Acomys history in south-western Sahara. We tested the specific predictions that: (1) several mitochondrial clades can be identified and that they coincide with the described species; (2) successive phases of desert expansion and contraction during the last 3 Myr have resulted in several phases of demographic expansion and population fragmentation in Acomys; and (3) isolation-by-distance occurs. The extent of phylogeographic patterns and molecular genetic diversity (cytochrome b gene and D-loop) were addressed in a survey of 90 individuals of Acomys from 38 localities. Our phylogeographical analyses show a strong genetic structure within western Saharan Acomys, with several phylogroups displaying non-overlapping geographic distributions. Restricted gene flow with isolation-by-distance was recorded and a signal of population expansion was detected within several clades. We suggest that during arid or semi-arid paleoclimatic periods, when large sandy areas were present, Acomys was restricted to rocky massifs, whereas, in more humid periods, when savannah and/or steppe habitat prevailed, this species was able to disperse and to survive outside rocky areas because food resources were abundant. Based on a comprehensive sampling and the use of an integrative approach (i.e. combining cytogenetic, molecular and morphological data), we firmly propose that Acomys airensis should be considered as a junior synonym of Acomys chudeaui. © 2009 The Linnean Society of London, Biological Journal of the Linnean Society, 2009, 98, 29,46. [source] Development and validation of a questionnaire measuring quality of life in primary caregivers of children with atopic dermatitis (QPCAD)BRITISH JOURNAL OF DERMATOLOGY, Issue 3 2009K. Kondo-Endo Summary Background, Disease-specific health-related quality of life (HRQoL) instruments for primary caregivers of children with atopic dermatitis are useful in evaluating the efficacy of treatment in clinical practice and study. However, no such scale has been available in Japan. Objectives, To develop and validate a self-administered instrument specifically designed to measure quality of life in primary caregivers of children with atopic dermatitis (QPCAD). Methods, This study consisted of three successive phases: the item generation phase, pilot test phase and validation phase. In the item generation phase, questionnaire items were derived from 33 qualitative interviews with primary caregivers. In the pilot test phase, the face and content validity of the preliminary scale were assessed (n = 33). In the validation phase, the questionnaire was finalized and assessed in terms of statistical performance (n = 416). Results, The QPCAD included 19 items in the following categories: ,exhaustion', ,worry about atopic dermatitis', ,family cooperation' and ,achievement'. The reliability of internal consistency was fair (Cronbach's alpha coefficients 0·66,0·87). The QPCAD subscales and total score were significantly correlated with psychological health, physical health, anxiety, depression and severity score, with mild to moderate correlation coefficients. Test,retest reliability and responsiveness to change in severity were also satisfactory. Conclusions, The QPCAD is an appropriate tool for assessing HRQoL of primary caregivers of children with atopic dermatitis in clinical practice and clinical trials. [source] DESENSITIZATION OF GUINEA-PIG TAENIA CAECI SMOOTH MUSCLE INDUCED BY A LOW CONCENTRATION OF CARBACHOLCLINICAL AND EXPERIMENTAL PHARMACOLOGY AND PHYSIOLOGY, Issue 11 2007Shigeru Hishinuma SUMMARY 1In guinea-pig taenia caeci smooth muscle we have found that 10,4 mol/L carbachol-induced desensitization to muscarinic agonists develops within 15,30 s, followed by transient resensitization at 1 min, whereas the desensitization to depolarizing high K+ develops with maximal desensitization at 1 min followed by sustained resensitization up to 30 min. In both cases, Ca2+ -dependent processes play a crucial role in determining the development of desensitization. 2To elucidate whether these peculiar processes of desensitization/resensitization may be induced by a lower concentration of carbachol, we examined the development of desensitization induced by 10,6 mol/L carbachol, because at this concentration carbachol is known to induce biphasic changes in intracellular Ca2+ concentrations, with a smaller transient increase followed by a larger sustained increase than seen with 10,4 mol/L carbachol. 3Contractile responses to muscarinic agonists (carbachol or AHR-602) and high K+ were desensitized by pretreatment with 10,6 mol/L carbachol for 30 min in a manner dependent on the presence of extracellular Ca2+. 4The development of 10,6 mol/L carbachol-induced desensitization to these muscarinic agonists in the presence of extracellular Ca2+ showed three successive phases: fast desensitization within 30 s, followed by transient resensitization at 1 min and the subsequent development of desensitization up to 30 min. In contrast, desensitization to high K+ did not develop up to 10 min and significant desensitization occurred at 30 min, with no apparent resensitization phase. 5These results suggest that the characteristics of the Ca2+ -dependent development of desensitization to muscarinic agonists, but not to high K+, are well maintained in desensitization induced by a lower concentration of carbachol. [source] | ||||||||||||||||