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Dominant Type (dominant + type)
Selected AbstractsRecent channel adjustments in alluvial rivers of Tuscany, central ItalyEARTH SURFACE PROCESSES AND LANDFORMS, Issue 6 2003Massimo RinaldiArticle first published online: 19 JUN 200 Abstract Drastic channel adjustments have affected the main alluvial rivers of Tuscany (central Italy) during the 20th century. Bed-level adjustments were identified both by comparing available topographic longitudinal profiles of different years and through field observations. Changes in channel width were investigated by comparing available aerial photographs (1954 and 1993,98). Bed incision represents the dominant type of vertical adjustment, and is generalized along all the fluvial systems investigated. The Arno River system is the most affected by bed-level lowering (up to 9 m), whereas lower incision (generally less than 2 m) is observed along the rivers of the southern part of the region. Human disturbances appear to be the dominant factors of adjustments: the main phase of vertical change occurred during the period 1945,80, in concomitance with the phase of maximum sediment mining activity at the regional scale. The second dominant type of adjustment that involved most of the rivers in the region consists of a narrowing of the active channel. Based on measurements of channel width conducted on aerial photographs, 38% of the reaches analysed experienced a narrowing greater than 50% of the initial channel width. The largest values of channel narrowing were observed along initially braided or sinuous with alternate bars morphologies in the southern portion of the region. A regional scheme of channel adjustments is derived, based on initial channel morphology and on the amounts of incision and narrowing. Different styles of channel adjustments are described. Rivers that were originally sinuous with alternate bars to braided generally became adjusted by a moderate incision and a moderate to intense narrowing; in contrast, sinuous-meandering channels mainly adjusted vertically, with a minor amount of narrowing. Copyright © 2003 John Wiley & Sons, Ltd. [source] Stratigraphic Control of Flow and Transport CharacteristicsGROUND WATER, Issue 6 2006Dwaine Edington Ground water flow and travel time are dependent on stratigraphic architecture, which is governed by competing processes that control the spatial and temporal distribution of accommodation and sediment supply. Accommodation is the amount of space in which sediment may accumulate as defined by the difference between the energy gradient and the topographic surface. The temporal and spatial distribution of accommodation is affected by processes that change the distribution of energy (e.g., sea level or subsidence). Fluvial stratigraphic units, generated by FLUVSIM (a stratigraphic simulator based on accommodation and sediment supply), with varying magnitudes and causes of accommodation, were incorporated into a hydraulic regime using MODFLOW (a ground water flow simulator), and particles were tracked using MODPATH (a particle-tracking algorithm). These experiments illustrate that the dominant type of accommodation process influences the degree of continuity of stratigraphic units and thus affects ground water flow and transport. When the hydraulic gradient is parallel to the axis of the fluvial system in the depositional environment, shorter travel times occur in low,total accommodation environments and longer travel times in high,total accommodation environments. Given the same total accommodation, travel times are longer when sea-level change is the dominant process than those in systems dominated by subsidence. [source] Wind-throw mortality in the southern boreal forest: effects of species, diameter and stand ageJOURNAL OF ECOLOGY, Issue 6 2007ROY L. RICH Summary 1Patterns of tree mortality as influenced by species, diameter and stand age were assessed across a gradient in wind disturbance intensity in a southern boreal forest in Minnesota, USA. Few previous studies have addressed how wind impacts boreal forests where fire was historically the dominant type of disturbance. 2We surveyed 29 334 trees of nine species within a 236 000 ha blowdown in the Boundary Waters Canoe Area Wilderness (BWCAW), in forests that have never been logged and were not salvaged after the windstorm. Within the disturbed area, a range of disturbance severity from zero to complete canopy mortality was present, overlaying an existing mosaic of fire origin stands. For this study, we derived an index of wind disturbance intensity by standardizing the observed disturbance severity using common species with similar diameter at breast height (d.b.h.) distributions. We then used multiple logistic regression to assess patterns of tree mortality across gradients in tree size and wind intensity index, and for three stand ages. 3Probability of mortality was higher with increasing ln d.b.h. for all nine species, with two species (Abies balsamea and Picea mariana) showing much more dramatic shifts in mortality with d.b.h. than the others. As hypothesized, the species most susceptible to windthrow at all d.b.h. classes were early successional and shade intolerant (Pinus banksiana, Pinus resinosa, Populus tremuloides) and those least susceptible were generally shade tolerant (e.g. Thuja occidentalis, Acer rubrum), although the intolerant species Betula papyrifera also had low mortality. 4Mortality rates were higher in mature (c. 90 years old) stands than for old and very old (c. 126,200 years old) stands, probably because old stands had already gone through transition to a multi-aged stage of development. 5Synthesis. Quantification of canopy mortality patterns generally supports disturbance-mediated accelerated succession following wind disturbance in the southern boreal forest. This wind-induced weeding of the forest favoured Thuja occidentalis, Betula papyrifera and Acer rubrum trees of all sizes, along with small Abies balsamea and Picea mariana trees. Overall, the net impact of wind disturbance must concurrently consider species mortality probability, abundance and diameter distributions. [source] The relationship between static and dynamic occlusion in 14,17-year-old school childrenJOURNAL OF ORAL REHABILITATION, Issue 7 2004A. S. Al-Hiyasat summary, This study investigated the relationship between static and dynamic occlusion in school children. A total of 447 subjects, within an age range of 14,17 years with no history of orthodontic treatment or trauma to the teeth were included in this study. Static occlusion was determined for both incisal and molar relationship. Dynamic occlusion was determined in lateral and protrusive movements of the mandible. The majority of the subjects had class I static occlusion for both incisor and molar relationship (45 and 54%, respectively). Canine-guided occlusion was the dominant type of dynamic occlusion (57%) and most of the subjects had no posterior contact in protrusive movement (78%). There was an association between canine guidance with class II static occlusion. Statistically, a significant relationship was found between the dynamic and static occlusion of the incisor (P < 0·001) but not with the molar (P > 0·05). [source] A four-fold humanity: Margaret Mead and psychological typesJOURNAL OF THE HISTORY OF THE BEHAVIORAL SCIENCES, Issue 2 2004Gerald SullivanArticle first published online: 19 MAR 200 Beginning in 1933, while working in New Guinea, Margaret Mead developed her so-called squares hypothesis. Mead never published its terms, though she made a brief comment on it in her autobiography, Blackberry Winter (1972), and the arguments found in Sex and Temperament in Three Primitive Societies (1935) and the research leading to Balinese Character (Bateson & Mead, 1942) bore its imprint. Beginning with William McDougall's distinction between temperament (innate predispositions) and character (learned organization of habit), Mead articulated a morphological approach to the interplay between biology and culture that yielded four primary and four intermediary personality types. Under specified but not inevitable circumstances, the conscious choices of a given people could render one or another of these types characteristic or predominantly stable within their population, giving each of the other types a definite relation to the dominant type and thereby the cultural ethos of its society. Persons of each type followed a developmental path specific to their type different both from that of other types and in its manifestations given the various relations of the individual's type to the dominant type. Mead's hypothesis was, therefore, a vision of the unity and diversity of a single human species as well as an approach to the differing psychological positioning of individuals in cultures. In examining Mead's hypothesis, this essay also takes up Mead's debts to several leading psychologists (McDougall, C. G. Jung, and Erik Erikson), and (provisionally) how her vision differed from that of Ruth Benedict. © 2004 Wiley Periodicals, Inc. [source] Culture and knowledge co-creation in R&D collaboration between MNCs and Chinese universitiesKNOWLEDGE AND PROCESS MANAGEMENT: THE JOURNAL OF CORPORATE TRANSFORMATION, Issue 2 2010Jianzhong Hong This paper examines the role of culture in university,industry R&D collaboration and knowledge interaction in the context of multinational corporations in China. Earlier university,industry studies focus primarily on one-way technology and knowledge transfer; however, the present study argues that in the studied context more interactive types of knowledge interaction like knowledge co-creation should be of key concern. The main challenge of the R&D collaboration lies in the understanding of culture in general and Chinese guanxi (interpersonal relationship) in particular in collaborative knowledge creation, in which the dominant type of knowledge involved is most often tacit, future oriented, complex and context-specific. This is particularly important when dealing simultaneously with multi-disciplinary applied research where cultural challenges appear prominent. Copyright © 2010 John Wiley & Sons, Ltd. [source] Iatrogenic vertebral artery injuryACTA NEUROLOGICA SCANDINAVICA, Issue 6 2005J. Inamasu Iatrogenic vertebral artery injury (VAI) results from various diagnostic and therapeutic procedures. The objective of this article is to provide an update on the mechanism of injury and management of this potentially devastating complication. A literature search was conducted using PubMed. The iatrogenic VAIs were categorized according to each diagnostic or therapeutic procedure responsible for the injury, i.e., central venous catheterization, cervical spine surgery, chiropractic manipulation, diagnostic cerebral angiography, percutaneous nerve block, and radiation therapy. The incidence, mechanisms of injury, and reparative procedures were discussed for each type of procedure. The type of VAI depends largely on the type of procedure. Laceration was the dominant type of acute injury in central venous catheterization and cervical spine surgery. Arteriovenous fistulae and pseudoaneurysms were the delayed complications. Arterial dissection was the dominant injury type in chiropractic manipulation and diagnostic cerebral angiography. Inadvertent arterial injection caused seizures or stroke in percutaneous nerve block. Radiation therapy was responsible for endothelial injury which in turn resulted in delayed stenosis and occlusion of the vertebral artery (VA). The proximal VA was the most vulnerable portion of the artery. Although iatrogenic VAIs are rare, they may actually be more prevalent than had previously been thought. Diagnosis of iatrogenic VAI may not always be easy because of its rarity and deep location, and a high level of suspicion is necessary for its early detection. A precise knowledge of the surgical anatomy of the VA is essential prior to each procedure to prevent its iatrogenic injury. [source] Microstructure and thermal history of metal particles in CH chondritesMETEORITICS & PLANETARY SCIENCE, Issue 6 2007J. I. GOLDSTEIN Four types of metal particles are common in all of these chondrites. Zoned and unzoned particles probably formed as condensates from a gas of chondritic composition in a monotonic cooling regime, as has been shown previously. We have demonstrated that these particles were cooled rapidly to temperatures below 500 K after they formed, and that condensation effectively closed around 700 K. Zoned and unzoned particles with exsolution precipitates, predominantly high-Ni taenite, have considerably more complex thermal histories. Precipitates grew in reheating episodes, but the details of the heating events vary among individual grains. Reheating temperatures are typically in the range 800,1000 K. Reheating could have been the result of impact events on the CH parent body. Some particles with precipitates may have been incorporated into chondrules, with further brief heating episodes taking place during chondrule formation. In addition to the four dominant types of metal particles, rare Ni-rich metal particles and Si-rich metal particles indicate that the metal assemblage in CH chondrites was a mixture of material that formed at different redox conditions. Metal in CH chondrites consists of a mechanical mixture of particles that underwent a variety of thermal histories prior to being assembled into the existing brecciated meteorites. [source] Recognizing diversity in coral symbiotic dinoflagellate communitiesMOLECULAR ECOLOGY, Issue 6 2007AMY M. APPRILL Abstract A detailed understanding of how diversity in endosymbiotic dinoflagellate communities maps onto the physiological range of coral hosts is critical to predicting how coral reef ecosystems will respond to climate change. Species-level taxonomy of the dinoflagellate genus Symbiodinium has been predominantly examined using the internal transcribed spacer (ITS) region of the nuclear ribosomal array (rDNA ITS2) and downstream screening for dominant types using denaturing gradient gel electrophoresis (DGGE). Here, ITS2 diversity in the communities of Symbiodinium harboured by two Hawaiian coral species was explored using direct sequencing of clone libraries. We resolved sixfold to eightfold greater diversity per coral species than previously reported, the majority of which corresponds to a novel and distinct phylogenetic lineage. We evaluated how these sequences migrate in DGGE and demonstrate that this method does not effectively resolve this diversity. We conclude that the Porites spp. examined here harbour diverse assemblages of novel Symbiodinium types and that cloning and sequencing is an effective methodological approach for resolving the complexity of endosymbiotic dinoflagellate communities harboured by reef corals. [source] | |||||||||||||