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Maximum Length (maximum + length)
Selected AbstractsLower esophageal palisade vessels and the definition of Barrett's esophagusDISEASES OF THE ESOPHAGUS, Issue 7 2008K. Ogiya SUMMARY., The designated area of the columnar-lined esophagus (CLE) is anatomically defined by the distal limit of the lower esophageal palisade vessels (LEPV) and the term ,Barrett's esophagus' is equally used along with the name CLE in Japan. The aim of this study was to investigate the actual prevalence of CLE based on the Japanese criteria and to evaluate the criteria per se. A total of 42 esophagi consecutively resected at this institute were included. All subjects underwent a surgical resection for squamous cell carcinoma of the esophagus. The position of the LEPV, squamocolumnar junction, the prevalence of CLE and intestinal metaplasia were investigated both pre- and postoperatively. Preoperative endoscopy revealed CLE based on the Japanese criteria in half of all patients. In the resected specimens the distal limit of LEPV was lower than the squamocolumnar junction in 95.2%. In other words, almost all cases had CLE (equivalent to Barrett's mucosa in Japanese criteria). However, most of the CLE areas were very short and their average maximum length was only about 5 mm. In addition, no intestinal metaplasia was observed in any of the CLE cases. Almost all individuals might therefore be diagnosed to have CLE or Barrett's mucosa based on precise endoscopic observations in Japan. The CLE located in a small area, e.g. less than 5 mm, defined according to the LEPV criteria without any other factor concerning typical Barrett's esophagus such as signs of gastroesophageal reflux should therefore be excluded from consideration as a high-risk mucosa. [source] POSTED OFFER MARKETS IN NEAR-CONTINUOUS TIME: AN EXPERIMENTAL INVESTIGATIONECONOMIC INQUIRY, Issue 3 2009DOUGLAS D. DAVIS This paper reports an experiment conducted to evaluate a "near-continuous" variant of the posted offer trading institution, where the number of periods in a market session is increased by reducing sharply each period's maximum length. Experimental results suggest that although decisions in time-truncated periods are not equivalent to periods of longer duration, extensive repetition improves considerably the drawing power of equilibrium predictions in some challenging environments. Nevertheless, significant deviations remain in the near-continuous framework. We also observe that the extra data collected in the near-continuous framework allow new insights into price convergence and signaling. (JEL C92, L12, L11) [source] A modeling approach to link food availability, growth, emergence, and reproduction for the midge Chironomus ripariusENVIRONMENTAL TOXICOLOGY & CHEMISTRY, Issue 11 2002Alexandre R. R. Péry Abstract We present models to link feeding with growth, emergence, and reproduction of the midge Chironomus riparius. These models are based on assumptions about the biology of this species and distinguish between males and females. The assumptions are the isomorphism of the chironomidae, the fact that much more energy is used for growth than for maintenance, and the existence of a maximum length for male and female larvae that does not depend on food availability. We supported our assumptions by experimental data and estimated the parameters of the model. We then successfully predicted the length pattern of 2-d-old larvae exposed in an artificial sediment to different feeding levels with different starting densities and also linked emergence time and growth pattern. We found our model to be consistent with data from another study and another species (Chironomus plumosus). As for reproduction, the mean number of eggs per mass was described as a linear function of feeding quantity. Our models could be used in sediment risk assessment to choose feeding level, to build effects models, or to predict the effects of toxicants at the population level. [source] Conductive Core,Sheath Nanofibers and Their Potential Application in Neural Tissue EngineeringADVANCED FUNCTIONAL MATERIALS, Issue 14 2009Jingwei Xie Abstract Conductive core,sheath nanofibers are prepared by a combination of electrospinning and aqueous polymerization. Specifically, nanofibers electrospun from poly(, -caprolactone) (PCL) and poly(L -lactide) (PLA) are employed as templates to generate uniform sheaths of polypyrrole (PPy) by in-situ polymerization. These conductive core,sheath nanofibers offer a unique system to study the synergistic effect of different cues on neurite outgrowth in vitro. It is found that explanted dorsal root ganglia (DRG) adhere well to the conductive core,sheath nanofibers and generate neurites across the surface when there is a nerve growth factor in the medium. Furthermore, the neurites can be oriented along one direction and enhanced by 82% in terms of maximum length when uniaxially aligned conductive core,sheath nanofibers are compared with their random counterparts. Electrical stimulation, when applied through the mats of conductive core,sheath nanofibers, is found to further increase the maximum length of neurites for random and aligned samples by 83% and 47%, respectively, relative to the controls without electrical stimulation. Together these results suggest the potential use of the conductive core,sheath nanofibers as scaffolds in applications such as neural tissue engineering. [source] Scapular development from the neonatal period to skeletal maturity: A preliminary studyINTERNATIONAL JOURNAL OF OSTEOARCHAEOLOGY, Issue 5 2007C. Rissech Abstract An understanding of the basic growth rates and patterns of development for each element of the human skeleton is important for a thorough understanding and interpretation of data in all areas of skeletal research. Yet surprisingly little is known about the detailed ontogenetic development of many bones, including the scapula. With the intention of describing the changes that accompany postnatal ontogeny in the scapula and algorithms to predict sub-adult age at death, this communication examines the development of the scapula through nine measurements (3 from the glenoidal area, 4 from the body and 2 related to the spinous process) by polynomial regression. Data were collected from 31 of the individuals that comprise the Scheuer Collection, which is housed at the University of Dundee (Scotland). Four of the derived mathematical curves (scapular length, infra- and suprascapular height and spine length) displayed linear growth, whilst three (maximum length of the glenoid mass, acromial width and scapular width) were best expressed by a second-degree polynomial and two (maximum and middle diameter of the glenoidal surface) by a third-degree polynomial. All single measurements proved useful in the prediction of age at death, although derived indices proved to be of limited value. In particular, scapular width, suprascapular height and acromial width showed reliable levels of age prediction until late adolescent years. Copyright © 2007 John Wiley & Sons, Ltd. [source] Annual Cycle of Planktothrix agardhii(Gom.) Anagn.INTERNATIONAL REVIEW OF HYDROBIOLOGY, Issue 3 2004& Kom. Abstract Changes in abundance, biovolume and morphology of Planktothrix agardhii in a natural population were followed over one year period in shallow fishpond Bílá Lhota (Central Moravia, Czech Republic). The selected environmental parameters (pH, oxygen, temperature, conductivity, nutrients, light) were measured at the surface and at the bottom of the fishpond, together with the Planktothrix abundances and filament morphology , filament length, width, shape, aerotopes (gas vacuoles) formation. The annual cycle of P. agardhii in this hypertrophic fishpond starts in March with the germination of hormogonia and the growth of overwintered filaments. The filament length quickly increases to a maximum length in April. The following summer period can be characterized by filament shortening and by changes in the aerotopes shape. On the other hand the abundance and biomass of P. agardhii is increasing until the maximum in August. Further shortening of filaments, loss of aerotopes and hormogoniae formation is typical for the autumn (October) with the average temperature of 9.4 °C. The population overwinters near the pond bottom in the form of hormogonia (60%) and filaments (40%). (© 2004 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) [source] Efficient algorithms for finding the (k, l)-core of tree networksNETWORKS: AN INTERNATIONAL JOURNAL, Issue 4 2002Ronald I. Becker Abstract Given a tree T = (V, E), with |V| = n, we consider the problem of selecting a subtree with at most k leaves and with a diameter of at most l which minimizes the sum of the distances of the vertices from the selected subtree. We call such a subtree the (k, l)-core of T. We provide two algorithms; the first one for unweighted trees has time complexity of O(n2), whereas the second one for weighted trees has time complexity of O(n2log n). The idea for both the algorithms is that, by starting from the tree T, we construct new rooted trees where the maximum length of a path is at most l. Then, for each new tree, we can apply a greedy-type procedure to find a subtree containing the root with at most k leaves and which minimizes the sum of the distances. © 2002 Wiley Periodicals, Inc. [source] Giant mitochondria in the retina cone inner segments of shrews of genus Sorex (Insectivora, Soricidae)THE ANATOMICAL RECORD : ADVANCES IN INTEGRATIVE ANATOMY AND EVOLUTIONARY BIOLOGY, Issue 2 2003Sara Lluch Abstract The retinas of three species of shrews (Sorex araneus, S. coronatus, and S. minutus) were analyzed. Two kinds of photoreceptors were identified according to (among other characteristics) the traits of the mitochondria of their inner segments. The rod inner segments contained several round or oval mitochondria distributed longitudinally inside the ellipsoid. The cone inner segment showed a few mitochondria, which we classified as megamitochondria (maximum length = 4.22 ,m in S. araneus, 5.68 ,m in S. coronatus, and 2.42 ,m in S. minutus). An analysis of serial thin sections in S. coronatus showed that these large organelles occurred in the apical and central portions of the ellipsoid. In the peripheral and basal regions of the ellipsoid, megamitochondria were frequently accompanied by smaller mitochondria. The giant mitochondria were irregular in form and densely packed, and a reduced cytosol was observed between each mitochondria. In general, they exhibited an electron-dense matrix and a complex system of cristae, which varied in length and array. In mammalian retina, megamitochondria have only been described in the ellipsoid of the tree shrews Tupaia glis and T. belangeri, two diurnal Scandentia with a rich-cone retina. In general terms, Sorex megamitochondria are morphologically very similar to those reported for Tupaia, especially in their arrangement in the cone ellipsoid. However, they differ in the orientation of the cristae. We propose that the ellipsoid of Sorex may serve two functions: as a source of energy for receptor cells, and as a device for improving the cone outer segment optics. Anat Rec Part A 272A:484,490, 2003. © 2003 Wiley-Liss, Inc. [source] RECTANGULARIZATION AND THE RISE IN LIMIT-LONGEVITY IN A SIMPLE OVERLAPPING GENERATIONS MODEL*THE MANCHESTER SCHOOL, Issue 1 2009GREGORY PONTHIERE Whereas overlapping generations (OLG) models with endogenous longevity do not distinguish between the rectangularization phenomenon and the rise in limit-longevity, these constitute two different demographic phenomena requiring a distinct modelling. This paper presents a two-period OLG model where the probability of survival from the first to the second period, as well as the maximum length of life, are endogenously determined and influenced by public policies. The issues of existence, uniqueness and stability of a steady state are studied. It is shown that the transition towards the steady state exhibits, under mild conditions, the observed succession of phases of rectangularization and derectangularization of survival curves. [source] Fold evolution and drainage development in the Zagros mountains of Fars province, SE IranBASIN RESEARCH, Issue 1 2008Lucy A. Ramsey ABSTRACT A central question in structural geology is whether, and by what mechanism, active faults (and the folds often associated with them) grow in length as they accumulate displacement. An obstacle in our understanding of these processes is the lack of examples in which the lateral growth of active structures can be demonstrated definitively, as geomorphic indicators of lateral propagation are often difficult, or even impossible to distinguish from the effects of varying lithology or non-uniform displacement and slip histories. In this paper we examine, using the Zagros mountains of southern Iran as our example, the extent to which qualitative analysis of satellite imagery and digital topography can yield insight into the growth, lateral propagation, and interaction of individual fold segments in regions of active continental shortening. The Zagros fold-and-thrust belt contains spectacular whaleback anticlines that are well exposed in resistant Tertiary and Mesozoic limestone, are often >100 km in length, and which contain a large proportion of the global hydrocarbon reserves. In one example, Kuh-e Handun, where an anticline is mantled by soft Miocene sediments, direct evidence of lateral fold propagation is recorded in remnants of consequent drainage patterns on the fold flanks that do not correspond to the present-day topography. We suggest that in most other cases, the soft Miocene and Pliocene sediments that originally mantled the folds, and which would have recorded early stages in the growth histories, have been completely stripped away, thus removing any direct geomorphic evidence of lateral propagation. However, many of the long fold chains of the Zagros do appear to be formed from numerous segments that have coalesced. If our interpretations are correct, the merger of individual fold segments that have grown in length is a major control on the development of through-going drainage and sedimentation patterns in the Zagros, and may be an important process in other regions of crustal shortening as well. Abundant earthquakes in the Zagros show that large seismogenic thrust faults must be present at depth, but these faults rarely reach the Earth's surface, and their relationship to the surface folding is not well constrained. The individual fold segments that we identify are typically 20,40 km in length, which correlates well with the maximum length of the seismogenic basement faults suggested from the largest observed thrusting earthquakes. This correlation between the lengths of individual fold segments and the lengths of seismogenic faults at depth suggest that it is possible, at least in some cases, that there may be a direct relationship between folding and faulting in the Zagros, with individual fold segments underlain by discrete thrusts. [source] Stratigraphic and structural expression of the lateral growth of thrust fault-propagation folds: results and implications from kinematic modellingBASIN RESEARCH, Issue 2 2003Kate A. Cooper In order to better understand the development of thrust fault-related folds, a 3D forward numerical model has been developed to investigate the effects that lateral slip distribution and propagation rate have on the fold geometry of pre- and syn-tectonic strata. We consider a fault-propagation fold in which the fault propagates upwards from a basal decollement and along-strike normal to transport direction. Over a 1 Ma runtime, the fault reaches a maximum length of 10 km and accumulates a maximum displacement of 1 km. Deformation ahead of the propagating fault tip is modelled using trishear kinematics while backlimb deformation is modelled using kink-band migration. The applicability of two different lateral slip distributions, namely linear-taper and block-taper, are firstly tested using a constant lateral propagation rate. A block-taper slip distribution replicates the geometry of natural fold-thrusts better and is then used to test the sensitivity of thrust-fold morphology to varied propagation rates in a set of fault-propagation folds that have identical final displacement to length (Dmax/Lmax) ratios. Two stratigraphic settings are considered: a model in which background sedimentation rates are high and no topography develops, and a model in which a topographic high develops above the growing fold and local erosion, transport and deposition occur. If the lateral propagation rate is rapid (or geologically instantaneous), the fault tips quickly become pinned as the fault reaches its maximum lateral extent (10 km), after which displacement accumulates. In both stratigraphic settings, this leads to strike-parallel rotation of the syn-tectonic strata near the fault tips; high sedimentation rates relative to rates of uplift result in along-strike thinning over the structural high, while low sedimentation rates result in pinchout against it. In contrast, slower lateral propagation rates (i.e. up to one order of magnitude greater than slip rate) lead to the development of along-strike growth triangles when sedimentation rates are high, whereas when sedimentation rates are low, offflap geometries result. Overall we find that the most rapid lateral propagation rates produce the most realistic geometries. In both settings, time-equivalent units display both nongrowth and growth stratal geometries along-strike and the transition from growth to nongrowth has the potential to delineate the time of fault/fold growth at a given location. This work highlights the importance of lateral fault-propagation and fault tip pinning on fault and fold growth in three dimensions and the complex syn-tectonic geometries that can result. [source] Ileocecal interposition for Hirschsprung's disease: a case reportCOLORECTAL DISEASE, Issue 9 2008F. Penninckx An ileocecal interposition (ICI) between the descending colon and anus was performed in a girl, 14 months old, with congenital aganglionosis up to the sigmoid colon. The left colon could not safely be mobilised because the paracolic arcade had been interupted during a preceding colostomy construction. The functional result, 14 years after reconstruction, is excellent: 1,2 easy defecations per day with normal continence for flatus and stool. An ICI may be an appropriate rescue procedure, saving a maximum length of normally innervated bowel and providing a neorecta1 reservoir. [source] Length,weight relationships for 36 fish populations from a disturbed tropical estuary in northern ColombiaJOURNAL OF APPLIED ICHTHYOLOGY, Issue 5 2009J. De la Hoz-M Summary The study reports length,weight relationships for 36 species belonging to 20 families of the estuarine zone of the Sinú River in northern Colombia. To the best knowledge of the authors, this study presents the first study on length,weight relationships for 10 species worldwide as well as seven new maximum lengths. [source] Taxonomic confusion and market mislabelling of threatened skates: important consequences for their conservation statusAQUATIC CONSERVATION: MARINE AND FRESHWATER ECOSYSTEMS, Issue 3 2010Samuel P. Iglésias Abstract 1.The iconic European common skate (Dipturus batis) has been described as the first clear case of a fish species brought to the brink of extinction by commercial fishing. Its listing was upgraded to Critically Endangered on the 2006 IUCN Red List of Threatened Species. According to FAO fishery statistics, France is responsible for 60.2% of the 502 tonnes reported as ,D. batis' in the 2005 world landings. 2.Noticeable phenotypic differences within the species and inconsistencies in published data on its sexual maturation required careful re-examination of its taxonomy. Morphology, genetics, and life history reveal that two distinct species have been erroneously confused since the 1920s under the single scientific name D. batis. Here it is argued that they should be resurrected as two valid species. The common skate D. batis species-complex is split into two nominal species, the blue skate (provisionally called D. cf. flossada) and the flapper skate (D. cf. intermedia) with maximum lengths of 143.2,cm and 228.8,cm respectively. 3.This taxonomic confusion puts into question all previously accumulated data based on D. batis. Its endangered status highlights the need for an extensive reassessment of population collapses with accurately identified species. In 2006/2007 an extensive survey (4110 skates, 14.081 tonnes by weight) was conducted in the main French ports of the D. batis species-complex and relatives (D. oxyrinchus, D. nidarosiensis and Rostroraja alba) that are mixed together in landings under the names ,D. batis' and ,D. oxyrinchus'. 4.The survey reveals that official fishery statistics mask species-specific declines, due to the mislabelling of five species under only two landing names. Trends in landings since the 1960s and the life history of these species suggest a dramatic decline and collapse of the spawning stock, preventing the recovery of relict populations. 5.The risk of extinction of these depleted species may be higher than previously assessed and might be unavoidable without immediate and incisive conservation action. Copyright © 2009 John Wiley & Sons, Ltd. [source] | |||||||||||||||||||