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Second Type (second + type)
Selected AbstractsGeological constraints on Antarctic palaeo-ice-stream retreatEARTH SURFACE PROCESSES AND LANDFORMS, Issue 4 2008Colm Ó Cofaigh Abstract Submarine landforms preserved in bathymetric troughs on the Antarctic continental shelf show that the style of ice stream retreat across the shelf following the last glacial maximum varied between different troughs. Three styles of retreat are inferred from the geological evidence: rapid, episodic and slow. Rapid retreat by ice stream floatation and calving is recorded by the preservation of a landform assemblage of unmodified streamlined subglacial bedforms including mega-scale glacial lineations (MSGLs) that record streaming flow along these troughs. These elongate bedforms are not overprinted by recessional glacial landforms formed transverse to ice flow such as moraines or grounding-zone wedges, and overlying deglacial sediments are thin. A second type of landform assemblage consists of MSGLs overprinted or interrupted by transverse grounding-zone wedges. This assemblage implies episodic retreat between successive grounding-zone positions. The third type of landform assemblage is that of numerous, closely spaced, recessional moraines and intermittent grounding-zone wedges that overlie and interrupt MSGLs. This assemblage records the slow retreat of grounded ice across the shelf. Variation in the style of ice stream retreat between the different bathymetric troughs indicates that Antarctic palaeo-ice-streams did not respond uniformly to external forcing at the end of the last glacial cycle. Rather, their diachronous retreat reflects the dominance of local controls in the form of bathymetry and drainage basin size. More broadly, these data show that retreat of marine-based ice sheets in areas of reverse bed slope is not necessarily catastrophic, and they provide important constraints for numerical models that attempt to predict the dynamics of large polar ice sheets. Copyright © 2008 John Wiley & Sons, Ltd. [source] Identification of soil degradation during earthquake excitations by Bayesian inferenceEARTHQUAKE ENGINEERING AND STRUCTURAL DYNAMICS, Issue 6 2003Jianye Ching Abstract A Bayesian inference approach is introduced to identify soil degradation behaviours at four downhole array sites. The approach of inference is based on a parametric time-varying infinite impulse response filter model. The approach is shown to be adaptive to the changes of filter parameters and noise amplitudes. Four sites, including the Lotung (Taiwan), Chiba (Japan), Garner Valley (California), and Treasure Island (California) sites with downhole seismic arrays are analysed. Our results show two major types of soil degradation behaviour: the well-known strain-dependent softening, and reduction in stiffness that is not instantaneously recoverable. It is also found that both types of soil degradation are more pronounced in sandy soils than in clayey soils. The mechanism for the second type of soil degradation is not yet clear to the authors and suggested to be further studied. Copyright © 2003 John Wiley & Sons, Ltd. [source] The individual tolerance concept is not the sole explanation for the probit dose-effect model,ENVIRONMENTAL TOXICOLOGY & CHEMISTRY, Issue 2 2000Michael C. Newman Abstract Predominant methods for analyzing dose- or concentration-effect data (i.e., probit analysis) are based on the concept of individual tolerance or individual effective dose (IED, the smallest characteristic dose needed to kill an individual). An alternative explanation (stochasticity hypothesis) is that individuals do not have unique tolerances: death results from stochastic processes occurring similarly in all individuals. These opposing hypotheses were tested with two types of experiments. First, time to stupefaction (TTS) was measured for zebra fish (Brachydanio rerio) exposed to benzocaine. The same 40 fish were exposed during five trials to test if the same order for TTS was maintained among trials. The IED hypothesis was supported with a minor stochastic component being present. Second, eastern mosquitofish (Gambusia holbrooki) were exposed to sublethal or lethal NaCl concentrations until a large portion of the lethally exposed fish died. After sufficient time for recovery, fish sublethally exposed and fish surviving lethal exposure were exposed simultaneously to lethal NaCl concentrations. No statistically significant effect was found of previous exposure on survival time but a large stochastic component to the survival dynamics was obvious. Repetition of this second type of test with pentachlorophenol also provided no support for the IED hypothesis. We conclude that neither hypothesis alone was the sole or dominant explanation for the lognormal (probit) model. Determination of the correct explanation (IED or stochastic) or the relative contributions of each is crucial to predicting consequences to populations after repeated or chronic exposures to any particular toxicant. [source] Multiple cell death programs: Charon's lifts to HadesFEMS YEAST RESEARCH, Issue 2 2004Wilfried Bursch Abstract Cells use different pathways for active self-destruction as reflected by different morphology: while in apoptosis (or "type I") nuclear fragmentation associated with cytoplasmic condensation but preservation of organelles is predominant, autophagic degradation of cytoplasmic structures preceding nuclear collapse is a characteristic of a second type of programmed cell death (PCD). The diverse morphologies can be attributed , at least to some extent , to distinct biochemical and molecular events (e.g. caspase-dependent and -independent death programs; DAP-kinase activity, Ras-expression). However, apoptosis and autophagic PCD are not mutually exclusive phenomena. Rather, diverse PCD programs emerged during evolution, the conservation of which apparently allows cells a flexible response to environmental changes, either physiological or pathological. [source] Mixed-species bird flocks in dipterocarp forest of north-central Burma (Myanmar)IBIS, Issue 4 2001DAVID I. KING We studied the bird community in deciduous, dipterocarp forest of north-central Burma (Myanmar) during December 1994, March 1996, and January 1997 and 1999. Most members of this community participated in mixed-species flocks. Seventy-three flocks were encountered during our study, containing 52 species. Of these, 25 species occurred in more than 10% of flocks, and were included in our analyses. There were 26 significant correlations among species pairs, 25 of which were positive. Cluster analysis indicated that there were three principal types of flocks: one consisting mostly of small passerines and picids, commonly including Common Wood-Shrike, Small Minivet and White-browed Fantail, among others; a second type consisting mainly of sylviids, e.g. Arctic, Dusky and Radde's Warblers; and a third type which generally centred around Greater and Lesser Necklaced Laughingthrushes. Bird-eating hawks were numerous at these sites, and we witnessed several attacks on flocks during the study. Thus we infer that enhanced protection from predation is an important benefit conferred by flock membership. In contrast, there was little overlap in foraging behaviour among species, suggesting that foraging facilitation is a relatively minor benefit enjoyed by flock members, although we did observe White-browed Fantails and Greater Racket-tailed Drongos kleptoparasitizing other species on occasion. [source] RECONCILIATION AS A PNEUMATOLOGICAL MISSION PARADIGM: SOME PRELIMINARY REFLECTIONS BY AN ORTHODOXINTERNATIONAL REVIEW OF MISSION, Issue 372 2005Petros Vassiliadis This article underlines the importance of reconciliation and healing in the life and mission of the church. It develops a new theology of mission that is no longer based on the old Christocentric uni-versalism but on a new trinitarian (i.e. pneumatological) understanding of the witness of the church. This is possible nowadays because of the reinforcement of pneumalology into missiologi-cal reflections, which together with the amazing expansion worldwide of the Pentecostal movement, determines the present day Christian mission. The article it based on the assumption that the Holy Spirit in both the biblical and patristic traditions is first and foremost eschatologically- (Acts 2:17ff) and communion- (2 Cor. 13:13) oriented. Since, however, a pneumatological approach of Christian mission cannot be received in the wider Christian constituency unless it is christologically conditioned, the article makes Christology its starting point. It argues that on the basis of Christ's teaching, life and work, the apostles were, and all Christians thereafter are commissioned to proclaim not a set of given reli-gious convict urns, doctrines and moral commands, but the coming kingdom. The message, therefore, is the good news of a new reality of full-scale reconciliation. From the epistemological point of view, the article builds upon the existence of two types of pneumatology in the history of the church. One type is "historical" and is more familiar in the West. It understands the Holy Spirit as fully dependent upon, and being the agent of Christ in order to fulfil the task of mission. The other type is "eschatological", and id more widespread in the East. It understands the Holy Spirit as the source of Christ, and the church in term more of ,coming together', i.e., as the eschatological synaxis of the people of God in hut Kingdom, than of ,going forth'for mission. Taking thu second type of pneumatology one step further, the article argues that mission in the conventional sense is the outcome and not the source of Christian theology. That is why for the Orthodox what constitutes the essence of the church is not her mission but the Eucharist, the divine Liturgy; the mission is the meta-liturgy, the Liturgy after the Liturgy. Nevertheless, reconciliation being the primary precondition of the Eucharist, it also automatically becomes a source of mission. [source] Principal-Agent Problems in Humanitarian Intervention: Moral Hazards, Adverse Selection, and the Commitment DilemmaINTERNATIONAL STUDIES QUARTERLY, Issue 4 2009Robert W. Rauchhaus A number of recent studies have concluded that humanitarian intervention can produce unintended consequences that reduce or completely undermine conflict management efforts. Some analysts have argued that the incentive structure produced by third parties is a form of moral hazard. This paper evaluates the utility of moral hazard theory and a second type of principal-agent problem known as adverse selection. Whereas moral hazards occur when an insured party has an opportunity to take hidden action once a contract is in effect, adverse selection is the result of asymmetric information prior to entering into a contract. Failing to distinguish between these two types of principal-agent problems may lead to policy advice that is irrelevant or potentially harmful. Along with introducing the concept of adverse selection to the debate on humanitarian intervention, this study identifies a commitment dilemma that explains why third parties operating in weakly institutionalized environments may be unable to punish groups that take advantage of intervention. [source] Deaths Between Bedrails and Air Pressure MattressesJOURNAL OF AMERICAN GERIATRICS SOCIETY, Issue 6 2002Steven H. Miles MD OBJECTIVES: To describe how patients die by becoming trapped between therapeutic air pressure mattresses and bed rails. DESIGN: A retrospective review of all voluntary reports deaths in beds with air mattresses that can be found in the Food and Drug Administration's on-line databases of adverse medical events that cover 1994 to 2001. SETTING: Death reports come from manufacturers, medical staff, and coroners and describe deaths in hospitals, nursing homes, and home care, although type of care site is often not given. MEASUREMENTS: Event descriptions were reviewed to determine how the person became entrapped in the rail and how responsibility for the event was allocated. RESULTS: There were 35 deaths involving many product lines. Twenty-one deaths involved overlay air mattresses placed on top of a regular mattress. Thirteen patients died in beds with built-in air mattresses. Compression of the mattress allowed an off-center person to slide against the rail where reexpansion of the mattress kept the person compressed against the rail. Two patterns were seen. In one, the mattress bunched up behind a person who was lying on the side of the bed, pushing the neck against a bedrail. In the second type, a patient died after sliding off the bed and having the neck or chest compressed between the rail and bed. Manufacturers attributed the deaths to poor clinical decision-making or inadequate monitoring. CONCLUSIONS: Lethal asphyxiation in beds with air pressure mattresses is a variant of bedrail-mattress entrapment that requires redesign by bed manufacturers and risk awareness by clinicians. [source] Dormant ascospores of Talaromyces macrosporus are activated to germinate after treatment with ultra high pressureJOURNAL OF APPLIED MICROBIOLOGY, Issue 1 2004J. Dijksterhuis Abstract Aims:, Ascospores of Talaromyces macrosporus are constitutively dormant and germinate after a strong external shock, classically a heat treatment. This fungus is used as a model system to study heat resistance leading to food spoilage after pasteurization. This study evaluates the effect of high pressure on the germination behaviour of these spores. Methods and Results:, Ascospore containing bags were subjected to ultra high pressure and spores were plated out on agar surfaces. Untreated suspensions showed invariably very low germination. Increased germination of ascospores occurred after short treatments at very high pressure (between 400 and 800 MPa). Activation is partial compared with heat activation and did not exceed 6·9% (65 times that of untreated suspensions) of the spore population. Maximum activation was attained shortly (10 s,3 min) after the pressure was applied and accompanied by cell wall deformations as judged by scanning electron microscopy. The spores observed in this study were harvested from cultures that were 39,58 days old. The maturity of spores at similar developmental stages was measured by assessing the heat resistance of ascospores. Between 20 and 40 days heat resistance increased 2·4-fold, but only an additional increase of 1·3-fold was observed at later stages (40,67 days). Conclusions:, Our investigations show that high pressure constitutes a second type of shock that can activate heat-resistant ascospores to germinate. Activation is maximal after very short treatments and accompanied with changes in the cell wall structure. High-pressure activation is not the result of immaturity of the ascospores. Significance and Impact of the Study: These observations are relevant for the application of high pressure as a novel pasteurization method. [source] Zircon U,Pb age and Hf isotope evidence for contrasting origin of bimodal protoliths for ultrahigh-pressure metamorphic rocks from the Chinese Continental Scientific Drilling projectJOURNAL OF METAMORPHIC GEOLOGY, Issue 8 2007R.-X. CHEN Abstract A combined study of zircon morphology, U,Pb ages and Hf isotopes as well as whole-rock major and trace elements was carried out for ultrahigh-pressure (UHP) eclogite and felsic gneiss from the main hole (MH) of the Chinese Continental Scientific Drilling (CCSD) project in the Sulu orogen. The results show contrasting Hf isotope compositions for bimodal UHP metaigneous rocks, pointing to contrasting origins for their protoliths (thus dual-bimodal compositions). The samples of interest were from two continuous core segments from CCSD MH at depths of 734.21,737.16 m (I) and 929.67,932.86 m (II) respectively. Zircon U,Pb dating for four samples from the two core segments yields two groups of ages at 784 ± 17 and 222 ± 3 Ma, respectively, corresponding to protolith formation during supercontinental rifting and metamorphic growth during continental collision. Although the Triassic UHP metamorphism significantly reset the zircon U,Pb system of UHP rocks, the Hf isotope compositions of igneous zircon can be used to trace their protolith origin. Contrasting types of initial Hf isotope ratios are, respectively, correlated with segments I and II, regardless of their lithochemistry. The first type shows positive ,Hf(t) values of 7.8 ± 3.1 to 6.0 ± 3.0, with young Hf model age of 1.03 and 1.11 Ga. The second type exhibits negative ,Hf(t) values of ,6.9 ± 1.6 to ,9.1 ± 1.1, with old Hf model ages of 2.11 and 2.25 Ga. It appears that the UHP rocks from the two segments have protoliths of contrasting origin. Consistent results are also obtained from their trace element compositions suggesting that mid-Neoproterozoic protoliths of bimodal UHP metaigneous rocks formed during supercontinental rifting at the northern margin of the South China Block. Thus, the first type of bimodal magmatism formed by rapid reworking of juvenile crust, whereas the second type of bimodal magmatism was principally generated by rift anatexis of Paleoproterozoic crust. Melting of orogenic lithosphere has potential to bring about bimodal magmatism with contrasting origins. Because arc,continent collision zones are the best place to accumulate both juvenile and ancient crusts, the contrasting types of bimodal magmatism are proposed to occur in an arc,continent collision orogen during the supercontinental rifting, in response to the attempted breakup of the supercontinent Rodinia at c. 780 Ma. [source] ECOSYSTEM MODELING: A TOOL TO UNDERSTAND THE INTERACTIONS BETWEEN EXTRACTIVE AND FED AQUACULTUREJOURNAL OF PHYCOLOGY, Issue 2001Article first published online: 24 SEP 200 Yarish, C. 1, Rawson, Jr. M. V.2, Chopin, T.3, Wang, D. R.4, Chen, C.4, Carmona, R.1, Chen, C.5 , Wang, L.4, Ji , R.5 and Sullivan, J.5 1University of Connecticut, Stamford, Connecticut 06901-2315, USA; 2Georgia Sea Grant College Program, Athens, GA 30602-3636, USA; 3University of New Brunswick, Saint John, NB, E2L 4L5, Canada; 4Marine and Fishery Dept. of Hainan Province, Haikou, Hainan, P. R. China; 5The University of Georgia, Athens, GA 30602-3636, USA One of the most difficult tasks resource managers face is understanding the carrying capacity of coastal waters for aquaculture. Aquaculture, like many other human activities, can threaten coastal waters. Aquaculture producing shrimp and finfish depends on supplemental feeding and can contribute to eutrophication. A second type, involving shellfish and macroalgae, extracts plankton and nutrients from surrounding waters, and can have a significant positive impact on moderately eutrophic waters. Ecosystem modeling offers a 3-dimensional physical, chemical and biological simulation that can help understand and predict the impacts of aquaculture on coastal embayments. Such a model is being explored for Xincun Bay (22 km2), which is located in southeastern Hainan Province, China. Aquaculture in Xincun Bay includes 6500 fish pens, 100 ha of shrimp ponds, pearl oyster culture rafts and Kappaphycus alvarezii culture that produces 2,000 mt (Oct.-May). The surrounding area has ~ 15,000 people and Xincun City is a major offshore fishing and tourist center. The annual nitrogen and phosphorus removal capacity of Kappaphycus in Xincun Bay may have been in the order of 53.8 and 3.7 mt, respectively, during the 1999-2000 growing season. Lian Bay (~ 15 km2), a nearby bay with only Kappaphycus and pearl oyster culture (and little anthropogenic input), has a macroalgal production of 1,500 mt annually. The annual nitrogen and phosphorus removal capacity of Kappaphycus here may have been in the order of 25 and 0.33 mt, respectively. Our prototype model may hold the promise for showing the importance of integrating seaweed culture activities in the maintenance and health of coastal embayments. [source] Proboscis morphology and food preferences in nymphalid butterflies (Lepidoptera: Nymphalidae)JOURNAL OF ZOOLOGY, Issue 1 2001H. W. Krenn Abstract Many species of nymphalid butterflies only exceptionally visit flowers and feed instead on tree sap, juice of rotting fruits and other decaying substances. To investigate whether the proboscis morphology of these non-flower-visiting Nymphalidae differs from that of nectarivorous butterflies, representatives from 64 nymphalid species with known feeding preferences were examined. Morphometric comparison of the proboscis revealed characteristic differences in proboscis length, tip-region length, wall composition, and number and shape of proboscis sensilla between these two feeding guilds. The investigated non-flower-visiting species belonging to Apaturinae, Limenitidinae, Morphinae, Brassolinae, Nymphalinae and Satyrinae, possess a relatively short and light-coloured proboscis which has a long tip-region with a great number of club-shaped sensilla styloconica. Densely arranged, these sensilla form a flat brush located laterally from the openings into the food canal on the dorsal side of the tip-region. Among the non-flower-visiting species, a second type of proboscis was found in fruit-feeding Charaxinae the stout tip-region of which is equipped with more widely spaced sensilla styloconica. The investigated flower-visiting Heliconiinae, Nymphalinae, Satyrinae, Danainae and Ithomiinae are characterized by a slender, darker-coloured proboscis with a rather short tip-region bearing fewer sensilla styloconica in a loose arrangement. Discriminant analysis revealed that the tip-region length, the number of sensilla styloconica and the relative proboscis length are the most important discriminating variables between the flower-visiting and the non-flower-visiting species. The proboscis morphology of nymphalid butterflies corresponds with certain feeding habits and allow us to make predictions on their food preferences. The ,brush-tipped' proboscis seems to have a functional role in the accumulation of fluid and the uptake of liquid from wet surfaces such as rotting fruits or tree sap. We conclude from the phylogeny of the examined taxa that this derived proboscis tip morphology evolved several times independently as an adaptation to the exploitation of new food resources. [source] Landscapes of the Law: Injury, Remedy, and Social Change in ThailandLAW & SOCIETY REVIEW, Issue 1 2009David M. Engel Sociolegal theorists since Weber have postulated that state law operates by interacting with and responding to nonstate legal orders. This article, examining conceptions of injury and compensation in Thailand, analyzes two ways of mapping law onto the landscape. The first is associated with state law and legal institutions established at the turn of the twentieth century. The state legal system imagines space from the outside in, drawing a boundary line and applying law uniformly throughout the jurisdiction it has enclosed. A second type of mapping, which has been more familiar over the centuries to ordinary Thai people, imagines space from the inside out. Nonstate legal orders are associated with sacred centers and radiate outward, diminishing in intensity and effectiveness with distance. This article, based on extensive interviews with injured persons and other actors and observers in northern Thailand, examines the interconnections between these two ways of imagining the landscape of law. It suggests that recent transformations of Thai society have rendered ineffective the norms and procedures associated with the law of sacred centers. Consequently, state law no longer interacts with or responds to nonstate law and surprisingly plays a diminished role in the lives of ordinary people who suffer injuries. [source] Growth behavior and microstructure of ZnO epilayer on ,-LiAlO2(100) substrate by chemical vapor depositionPHYSICA STATUS SOLIDI (A) APPLICATIONS AND MATERIALS SCIENCE, Issue 2 2009Liuwen Chang Abstract Low lattice-mismatched ,-LiAlO2(100) substrates were employed to grow ZnO epitaxial films by chemical vapor deposition. The influence of growth temperature on growth behavior of ZnO was investigated. Results indicated that the low lattice-matched (100) crystallites nucleate on substrate at all growth temperatures employed. However, a second type of crystallites having an (0001) orientation can also nucleate on substrate at low growth temperature of 575 °C and 640 °C. The growth rate of the later crystallite is, however, higher than that of the (100) one and finally results in a single crystalline ZnO film having an [0001] azimuthal orientation. (© 2009 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) [source] Characterisation of CuInS2/ Zn(Se,O)/ZnO solar cells as a function of Zn(Se,O) buffer deposition kinetics in a chemical bathPROGRESS IN PHOTOVOLTAICS: RESEARCH & APPLICATIONS, Issue 7 2002A. M. Chaparro Thin-film solar cells of CuInS2/Zn(Se,O)/ZnO configuration have been studied from the point of view of their dependence on the Zn(Se,O) chemical bath deposition (CBD) conditions. The kinetics of deposition of the Zn(Se,O) buffer is followed during cell processing with a quartz crystal microbalance (QCM). Two different CBD growth mechanisms yield buffer layers with different properties. Under a predominant electroless deposition reaction, the resulting buffer layer has mixed ZnSe,ZnO composition. The solar cells with this buffer type show higher fill factor (FF) and lower open-circuit voltage (Voc). Under a chemical growth regime, the buffer layer has higher ZnSe proportion, giving rise to cells with higher VOC, but lower FF and stability. The parameters of this second type of cell also show major dependence on illumination effects (light-soaking effects). Electron-beam-induced current (EBIC) and cathodoluminescence (CL) measurements are carried out to characterise the CuInS2/Zn(Se,O) junctions formed under the two buffer growth regimes. Cross-sectional EBIC shows a wider space charge region (SCR) than expected for p-CuInS2 in contact with Zn(Se,O), and the p,n junction is driven within the CuInS2 phase. These results reflect a chemical modification of CuInS2, most probably caused by the ammonia of the bath solution. CL shows more defective interfaces when Zn(Se,O) is deposited under the chemical mechanism (slower deposition rate, hence longer contact time of the CuInS2 with the bath solution) than under the electroless kinetics (faster deposition rate). Copyright © 2002 John Wiley & Sons, Ltd. [source] Approximating average parameters of graphs,,RANDOM STRUCTURES AND ALGORITHMS, Issue 4 2008Oded Goldreich Abstract Inspired by Feige (36th STOC, 2004), we initiate a study of sublinear randomized algorithms for approximating average parameters of a graph. Specifically, we consider the average degree of a graph and the average distance between pairs of vertices in a graph. Since our focus is on sublinear algorithms, these algorithms access the input graph via queries to an adequate oracle. We consider two types of queries. The first type is standard neighborhood queries (i.e., what is the ith neighbor of vertex v?), whereas the second type are queries regarding the quantities that we need to find the average of (i.e., what is the degree of vertex v? and what is the distance between u and v?, respectively). Loosely speaking, our results indicate a difference between the two problems: For approximating the average degree, the standard neighbor queries suffice and in fact are preferable to degree queries. In contrast, for approximating average distances, the standard neighbor queries are of little help whereas distance queries are crucial. © 2008 Wiley Periodicals, Inc. Random Struct. Alg., 2008 [source] Asymmetric Polymer Bridging Between Starch-Coated Colloidal Particles and Pulp Fibres by Cationic PolyacrylamideTHE CANADIAN JOURNAL OF CHEMICAL ENGINEERING, Issue 5 2007Agatha Poraj-Kozminski Abstract Internal sizing agents are commonly used as additives in papermaking to impart hydrophobicity to paper. They are commonly added in the form of colloidal particles, stabilized by cationic starch. As an example we studied the deposition of micron-sized Alkyl Ketene Dimer (AKD) particles on pulp fibres by cationic polyacrylamide (cPAM), a common flocculent. It was found that cPAM did not adsorb on AKD particles stabilized by cationic starch. Despite this inability to adsorb, cPAM was found to drastically improve the deposition of AKD particles on pulp fibres. This deposition was ascribed to asymmetric polymer bridging, a phenomenon observed by us before, while studying clay deposition on fibres by polyethylene oxide. In asymmetric polymer bridging between two types of particles, the bridging polymer first adsorbs on one type of particle, since it is unable to adsorb on the second type. Asymmetric polymer bridging occurs when the enthalpy gain on both surfaces exceeds the entropy loss. The kinetics of AKD deposition on fibres was found to agree with the predictions of the asymmetric bridging theory. In addition, an increase in bond strength with time was found, due to starch and cPAM reconfiguration. The increase in AKD retention by cPAM is also observed in experiments on a laboratory twin-wire sheet former. Asymmetric polymer bridging by cPAM between starch-coated AKD particles and fibres is compared with classical polymer bridging by cPAM between fibres and AKD particles coated by carboxymethylcellulose. Des agents d'encollage internes sont communément utilisés comme additifs dans la fabrication du papier pour transmettre l'hydrophobicité au papier. Ils sont communément ajoutés sous la forme de particules colloïdales, stabilisées par l'amidon cationique. À titre d'exemple, on a étudié la déposition de particules microniques de dimère de cétène d'alkyle (AKD) sur des fibres de pâte par le polyacrylamide cationique (cPAM), un floculant commun. On a trouvé que le cPAM ne s'adsorbait pas sur les particules d'AKD stabilisées par l'amidon cationique. Malgré cette incapacité à s'adsorber, on a trouvé que le cPAM améliorait considérablement la déposition des particules d'AKD sur les fibres de pâte. Cette déposition est imputée au pontage de polymères asymétriques, un phénomène que nous avons observé précédemment, lors de l'étude de la déposition d'argile sur les fibres par l'oxyde de polyéthylène. Dans le pontage de polymères asymétriques entre deux types de particules, le polymère de pontage s'adsorbe d'abord sur un type de particules, vu qu'il est incapable de s'adsorber sur le second type de particules. Le pontage de polymères asymétriques survient lorsque le gain d'enthalpie sur les deux surfaces excède la perte d'entropie. On a trouvé que la déposition d'AKD sur les fibres concordait avec les prédictions de la théorie de pontage asymétrique. En outre, on a observé une augmentation de la force de liaison dans le temps, en raison de la reconfiguration de l'amidon et du cPAM. L'augmentation de la rétention de l'AKD par le cPAM est également observée dans les expériences sur un appareil de formage de feuilles à double toile de laboratoire. Le pontage de polymères asymétriques par le cPAM entre les particules d'AKD enduites d'amidon et les fibres est comparé au pontage de polymères classique par le cPAM entre les fibres et les particules d'AKD enduites de carboxyméthylcellulose. [source] Wy are the transition paths in China and Eastern Europe different?THE ECONOMICS OF TRANSITION, Issue 1 2003A political economy perspective Abstract The purpose of this paper is to provide a framework linking communist regime collapse and privatizing economic reforms. The framework permits us to explain why certain communist regimes lost their monopoly of political power while others have not. We show that the essential difference between those communist regimes which survived economic reform and those which did not, lies in the nature of the privatization reform introduced by the communist leadership. The privatization that we call ,Market-Leninist', was implemented in China and Vietnam while the second type of privatization, termed ,Embezzlement for a rainy day' was the type of privatization implemented in Eastern Europe. We show, in the context of a game between rulers and the population, that the size of the repressive apparatus is the key element determining the type of privatization chosen by the rulers. JEL classification: P2, P3. [source] International medical graduates: Learning for practice in Alberta, CanadaTHE JOURNAL OF CONTINUING EDUCATION IN THE HEALTH PROFESSIONS, Issue 3 2007Jocelyn Lockyer PhD Abstract Introduction: There is little known about the learning that is undertaken by physicians who graduate from a World Health Organization,listed medical school outside Canada and who migrate to Canada to practice. What do physicians learn and what resources do they access in adapting to practice in Alberta, a province of Canada? Methods: Telephone interviews with a theoretical sample of 19 IMG physicians were analyzed using a grounded theory constant comparative approach to develop categories, central themes, and a descriptive model. Results: The physicians described two types of learning: learning associated with studying for Canadian examinations required to remain and practice in the province and learning that was required to succeed at clinical work in a new setting. This second type of learning included regulations and systems, patient expectations, new disease profiles, new medications, new diagnostic procedures, and managing the referral process. The physicians "settled" into their new setting with the help of colleagues; the Internet, personal digital assistants (PDAs), and computers; reading; and continuing medical education programs. Patients both stimulated learning and were a resource for learning. Discussion: Settling into Alberta, Canada, physicians accommodated and adjusted to their settings with learning activities related to the clinical problems and situations that presented themselves. Collegial support in host communities appeared to be a critical dimension in how well physicians adjusted. The results suggest that mentoring programs may be a way of facilitating settlement. [source] Dog Whistles and Democratic MandatesTHE POLITICAL QUARTERLY, Issue 4 2005ROBERT E. GOODIN Manipulative mixed messages from candidates to voters affect what governments are entitled to do in office. A party that wins an election gains a 'mandate to rule'. But there is a second type of mandate: a 'policy mandate' to enact specific policy proposals central to the winning party's campaign. Mixed-message politics in general can undermine policy mandates, and the use of 'dog whistle politics' - telling one group of voters one thing, while allowing or encouraging another group to believe another - makes the inferring of policy mandates especially problematic. Referendums provide only a partial remedy to dog whistle politics. Winning a clear policy mandate means forgoing dog whistle politics, despite the short term electoral advantage they may deliver. [source] A GYS1 gene mutation is highly associated with polysaccharide storage myopathy in Cob Normand draught horsesANIMAL GENETICS, Issue 1 2009B. Herszberg Summary Glycogen storage diseases or glycogenoses are inherited diseases caused by abnormalities of enzymes that regulate the synthesis or degradation of glycogen. Deleterious mutations in many genes of the glyco(geno)lytic or the glycogenesis pathways can potentially cause a glycogenosis, and currently mutations in fourteen different genes are known to cause animal or human glycogenoses, resulting in myopathies and/or hepatic disorders. The genetic bases of two forms of glycogenosis are currently known in horses. A fatal neonatal polysystemic type IV glycogenosis, inherited recessively in affected Quarter Horse foals, is due to a mutation in the glycogen branching enzyme gene (GBE1). A second type of glycogenosis, termed polysaccharide storage myopathy (PSSM), is observed in adult Quarter Horses and other breeds. A severe form of PSSM also occurs in draught horses. A mutation in the skeletal muscle glycogen synthase gene (GYS1) was recently reported to be highly associated with PSSM in Quarter Horses and Belgian draught horses. This GYS1 point mutation appears to cause a gain-of-function of the enzyme and to result in the accumulation of a glycogen-like, less-branched polysaccharide in skeletal muscle. It is inherited as a dominant trait. The aim of this work was to test for possible associations between genetic polymorphisms in four candidate genes of the glycogen pathway or the GYS1 mutation in Cob Normand draught horses diagnosed with PSSM by muscle biopsy. [source] Front and Back Covers, Volume 23, Number 5.ANTHROPOLOGY TODAY, Issue 5 2007Ocotober 200 Front and back covers caption, volume 23 issue 5 Front cover The front cover illustrates Julie J. Taylor's article on the outcome of the San people's court case against the Botswana government. The photo shows Roy Sesana, leader of the San organization First People of the Kalahari and chief appellant in the case, with Gordon Bennett, the San group's lawyer, at the start of the case in July 2004. In the course of the last century, the San or Bushmen of southern Africa became possibly the most studied indigenous group in the world. In addition to suffering land dispossession and violence during the colonial period, their image in the West has long been that of exotic and innocent ,Other', fuelled over time by the work of scientists, anthropologists and filmmakers among others. In recent years the San have become part of wider debates about indigeneity, poverty and development, often in relation to land rights. Many San have formed their own representative institutions and have also entered into relationships with national and international NGOs to campaign for their rights as an indigenous minority. From 2004, San claims to land in the Central Kalahari Game Reserve in Botswana drew unprecedented attention in the international media, due in part to the efforts of local NGOs and the British-based advocacy group Survival International. After protracted court proceedings and much controversy, the case finally came to an end in late 2006. At first sight the outcome appeared to offer victory to San applicants, but matters in the Central Kalahari are far from resolved, raising questions about the role of advocacy groups and the fate of marginalized San groups elsewhere. Back cover (IM)PERSONAL MONEY Roboti of Giribwa Village, Trobriand Islands (above) is seen wearing the armshell Nanoula and the necklace Kasanai. Both have been circulating in the kula for at least a century and were already famous when Malinowski saw them. He was sure that these valuables were not money because they were not an impersonal medium of exchange, but Marcel Mauss, in a long footnote to The gift, wrote: ,On this reasoning there has only been money when precious things have been really made into currency , namely have been inscribed and impersonalised, and detached from any relationship with any legal entity, whether collective or individual, other than the state that mints them, One only defines in this way a second type of money , our own.' This exchange was in some ways the high point of economic anthropology. The world of national currencies issued and controlled by states and banks must now come to terms with innumerable virtual instruments such as those seen flashing on the screens of the Chicago Mercantile Exchange (below). But, as the current ,sub-prime mortgage' crisis shows, these anonymous money instruments are still closely linked to personal credit. The challenge facing anthropologists today is to renew the legacy of Mauss and Malinowski in ways that illuminate such matters of universal practical concern. In this issue, Keith Hart argues that money, like society itself, is and always has been both personal and impersonal. A pragmatic anthropology should aim to show that the numbers on people's financial statements constitute a way of summarizing their relations with society at a given time. The next step is to explain how these numbers might serve in building a viable personal economy. When we are able to take responsibility for our own economic actions, we will understand better the social forces impinging on our lives. Then it will become more obvious how and why ruling institutions need to be reformed for all our sakes. [source] Three characteristic reactions of alkynes with metal compounds in organic synthesisAPPLIED ORGANOMETALLIC CHEMISTRY, Issue 3 2008Iwao Omae Abstract Alkynes have two sets of mutually orthogonal ,-bonds that are different from the ,-bonds of alkenes. These ,-bonds are able to bond with transition metal compounds. Alkynes easily bond with the various kinds of compounds having a ,-bond such as carbon monoxide, alkenes, other alkynes and nitriles in the presence of the transition metal compounds. The most representative reaction of alkynes is called the Pauson,Khand reaction. The Pauson,Khand reactions include the cyclization of alkynes with alkenes and carbon monoxide in the presence of cobalt carbonyls. Similar Pauson,Khand reactions also proceed in the presence of other transition metal compounds. These reactions are the first type of characteristic reaction of alkynes. Other various kinds of cyclizations with alkynes also proceed in the presence of the transition metal compounds. These reactions are the second type of characteristic reaction of alkynes. These include cyclooligomerizations and cycloadditions. The cyclooligomerizations include mainly cyclotrimerizations and cyclotetramerizations, and the cycloadditions are [2 + 2], [2 + 2 + 1], [2 + 2 + 2], [3 + 2], [4 + 2], etc., type cycloadditions. Alkynes are fairly reactive because of the high s character of their ,-bonds. Therefore, simple coupling reactions with alkynes also proceed besides the cyclizations. The coupling reactions are the third type of characteristic reactions of alkynes in the presence of, mainly, the transition metal compounds. These reactions include carbonylations, dioxycarbonylations, Sonogashira reactions, coupling reactions with aldehydes, ketones, alkynes, alkenes and allyl compounds. Copyright © 2008 John Wiley & Sons, Ltd. [source] Evaluation of the Impeller Shroud Performance of an Axial Flow Ventricular Assist Device Using Computational Fluid DynamicsARTIFICIAL ORGANS, Issue 9 2010Boyang Su Abstract Generally, there are two types of impeller design used in the axial flow blood pumps. For the first type, which can be found in most of the axial flow blood pumps, the magnet is embedded inside the impeller hub or blades. For the second type, the magnet is embedded inside the cylindrical impeller shroud, and this design has not only increased the rotating stability of the impeller but has also avoided the flow interaction between the impeller blade tip and the pump casing. Although the axial flow blood pumps with either impeller design have been studied individually, the comparisons between these two designs have not been conducted in the literature. Therefore, in this study, two axial flow blood pumps with and without impeller shrouds were numerically simulated with computational fluid dynamics and compared with each other in terms of hydraulic and hematologic performances. For the ease of comparison, these two models have the same inner components, which include a three-blade straightener, a two-blade impeller, and a three-blade diffuser. The simulation results showed that the model with impeller shroud had a lower static pressure head with a lower hydraulic efficiency than its counterpart. It was also found that the blood had a high possibility to deposit on the impeller shroud inner surface, which greatly enhanced the possibility of thrombus formation. The blood damage indices in both models were around 1%, which was much lower than the 13.1% of the axial flow blood pump of Yano et al. with the corresponding experimental hemolysis of 0.033 g/100 L. [source] The role of wood anatomy in phylogeny reconstruction of EricalesCLADISTICS, Issue 3 2007Frederic Lens The systematic significance of wood anatomical characters within Ericales is evaluated using separate and combined parsimony analyses including 23 wood characters and 3945 informative molecular characters. Analyses of wood features alone result in poorly resolved and conflicting topologies. However, when pedomorphic character states are coded as inapplicable, the combined bootstrap topology results in an increase of resolution and support at most deeper nodes compared with the molecular analyses. This suggests that phylogenetic information from the limited number of morphological characters is not completely swamped by an overwhelming amount of molecular data. Based on the morphology of vessels and fibers, and the distribution of axial parenchyma, two major wood types can be distinguished within Ericales: (i) a "primitive" type, nearly identical to the wood structure in the more basal outgroup Cornales, which is likely to have persisted in one major clade, and (ii) a "derived" type that must have evolved in at least two separate evolutionary lines. The occurrence of the first type is strongly correlated with shrubs to small trees growing in cold temperate or tropical montane regions, while the second type is common in tall trees of tropical lowlands. This favors the inclusion of ecologically adaptive features in phylogeny reconstruction. © The Willi Hennig Society 2006. [source] | ||||||||||||||||||||||||||||