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Copyright of Journal of Sport & Health Research is the property of Journal of Sport & Health Research and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Nematropica is the property of Organization of Nematologists of Tropical America and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Spiral density waves are thought to be excited in the accretion discs of accreting compact objects, including cataclysmic variable stars (CVs). Observational evidence has been obtained for a handful of systems in outburst over the last two decades. We present the results of a systematic study searching for spiral density waves in CVs, and report their detection in two of the sixteen observed systems. While most of the systems observed present asymmetric, non-Keplerian accretion discs during outburst, the presence of ordered structures interpreted as spiral density waves is not as ubiquitous as previously anticipated. From a comparison of systems by their system parameters it appears that inclination of the systems may play a major role, favouring the visibility and/or detection of spiral waves in systems seen at high inclination. [ABSTRACT FROM AUTHOR]

We present an extensive Doppler tomography study of the eclipsing nova-like EC21178–5417, which exhibits the classic accretion disc signature in the form of double-peak emission lines in its spectrum. Doppler tomograms confirm the presence of a strong, two-armed spiral pattern visible in the majority of the spectral lines studied. This makes EC21178–5417 one of the very few nova-likes that show spiral structure in their discs. We also report night-to-night changes in the position and relative strength of the spiral arms, revealing fluctuations on the conditions in the accretion disc. [ABSTRACT FROM AUTHOR]

The Chametla wetland is used by shorebirds as a stopover site during their autumn migration and it is also an important breeding area for several species of waterbirds. The objective of this work was to compare the bird assemblages in Chametla wetland during three sampling periods: 1) 1991–1992; 2) 1997–1998 which was subjected to El Nino Southern Oscillation (ENSO) climate conditions and 3) 2005–2006. Bird communities were characterized in terms of species composition and diversity, using similarity analysis. Bird assemblage composition differed across years and seasons. Seasonal variations in composition and diversity were related to the presence/absence of phenological-characterized species (migratory vs. wintering species). The highest species richness was recorded under the ENSO period (1997–1998). We observed a sharp decrease in shorebird numbers, with evident stress at the assemblage level throughout the entire study period. There seems to be a transition of the bird assemblages from shorebird dominance to a dominance by long-legged wading birds and waterfowl species, which could be related to water level variation and changes in the quality/availability of food in the intertidal zone. The joint pressures of regional climate variation combined with local anthropogenic perturbations may lead to changes in bird assemblage in the Chametla wetland. [ABSTRACT FROM AUTHOR]

We report on the discovery and analysis of 36 new eclipsing EL CVn-type binaries, consisting of a core helium-composition pre-white dwarf (pre-He-WD) and an early-type main-sequence companion. This more than doubles the known population of these systems. We have used supervised machine learning methods to search 0.8 million light curves from the Palomar Transient Factory (PTF), combined with Sloan Digital Sky Survey (SDSS), Panoramic Survey Telescope and Rapid Response System (Pan-STARRS) and Two-Micron All-Sky Survey (2MASS) colours. The new systems range in orbital periods from 0.46 to 3.8 d and in apparent brightness from ~14 to 16 mag in the PTF R or g☉ filters. For 12 of the systems, we obtained radial velocity curves with the Intermediate Dispersion Spectrograph at the Isaac Newton Telescope. We modelled the light curves, radial velocity curves and spectral energy distributions to determine the system parameters. The radii (0.3-0.7 Rϴ) and effective temperatures (8000-17 000 K) of the pre-He-WDs are consistent with stellar evolution models, but the masses (0.12-0.28 Mϴ) show more variance than models have predicted. This study shows that using machine learning techniques on large synoptic survey data is a powerful way to discover substantial samples of binary systems in short-lived evolutionary stages. [ABSTRACT FROM AUTHOR]

Spain’s current heat wave prevention plans are activated according to administrative areas. This study analyses the determination of threshold temperatures for triggering prevention-plan activation by reference to isoclimatic areas, and describes the public health benefits. We subdivided the study area – the Madrid Autonomous Region (MAR) – into three, distinct, isoclimatic areas: ‘North’, ‘Central’ and ‘South’, and grouped daily natural-cause mortality (ICD-10: A00-R99) in towns of over 10,000 inhabitants (2000–2009 period) accordingly. Using these three areas rather than the MAR as a whole would have resulted in a possible decrease in mortality of 73 persons (38–108) in the North area, and in aborting unnecessary activation of the plan 153 times in the Central area and 417 times in the South area. Our results indicate that extrapolating this methodology would bring benefits associated with a reduction in attributable mortality and improved effectiveness of public health interventions. [ABSTRACT FROM PUBLISHER]

In general, there are few studies that analyse the impact of low temperatures on mortality, and even fewer that extend this analysis to specific causes of mortality. This study had a twofold aim: Firstly, to analyse the trend in natural-, circulatory- and respiratory-cause mortality associated with cold waves in Castile-La Mancha (Spain) across a period of analysis of 34 years, which would confer an important degree of temporal representativeness on the results obtained; and secondly, to ascertain whether this impact had decreased over the years. Time series analysis using multivariate ARIMA models with data on daily natural-, circulatory- and respiratory-cause mortality in Castile-La Mancha. The independent variables were minimum daily temperature, mean daily pressure and mean daily relative humidity. We controlled for seasonalities and trend of the series, as well as influenza epidemics, cold-wave duration and chronological number in any given year. Data were stratified in three ten-year stages, i.e., 1975-1985, 1986-1996 and 1997-2008. The mortality trigger temperature was set at a minimum daily temperature of −2 °C, corresponding to the 4th ‰ of the minimum temperature series for the winter months considered. The impact on daily natural-cause mortality for each degree that the minimum daily temperature was below −2 °C was: 10.4 % (95 % CI 9.6-11.2) in the first decade; 11.9 % (95 % CI 11.0-12.8) in the second decade; and fell to 1.6 % (95 % CI 0.9-2.3) in the third. This same pattern was observed for circulatory- and respiratory-cause mortality, with the effect of cold being greater for respiratory causes. Socio-economic factors -both of adaptation and demographic- could account for this sharp decrease in mortality associated with low temperatures. These results question climate models which predict the effects of cold over long-term time horizons, while maintaining the risk attributable to low temperatures constant. Studies similar to ours should be undertaken in other regions to confirm whether it is solely local characteristics that explain this pattern or, on the contrary, whether the pattern is generalised. [ABSTRACT FROM AUTHOR]

Few studies have analysed the impact of heat and cold waves on mortality in a given population over the same time period and still fewer studies have analysed this impact in terms of cause-specific mortality. This study analysed the impact of both heat and cold waves on daily all-cause, circulatory-cause and respiratory-cause mortality in the region of Castile-La Mancha (CLM) 1975-2008. The dependent variable was daily all-, circulatory- and respiratory-cause mortality registered in CLM from 01-01-75 to 31-12-08, and the independent variables were maximum, minimum, mean daily temperature daily relative humidity and mean daily air pressure and other related variables, such as heat-wave duration, heat-wave number and pressure trend. Time-series analyses were performed using autoregressive integrated moving average models. The impact of heat on daily mortality was greater than that of cold, with a difference which proved statistically significant for all- and circulatory-cause mortality but not for respiratory-cause mortality. While 16.5 % CI 95 % (15.5-17.4) of summer mortality in CLM was attributable to heat, 12.9 % CI 95 % (12.2-13.8) of daily winter mortality was attributable to low temperatures. The variable, heat-wave duration, was of major importance in all-cause and respiratory-cause mortality, with wave persistence being related to a mean 3.5 % increase in daily organic-cause mortality. Although heat waves have a greater impact on daily mortality than do cold waves, the fact that there were more cold-wave than heat-wave days during the period analysed, coupled with the diseases implicated, means that specific prevention plans should be implemented for both extreme thermal events. [ABSTRACT FROM AUTHOR]

Approximately, 20 % of particulate and aerosol emissions into the urban atmosphere are of natural origin (including wildfires and Saharan dust). During these natural episodes, PM and PM levels usually exceed World Health Organisation (WHO) health protection thresholds. This study sought to evaluate the possible effect of advections of particulate matter from biomass fuel combustion on daily specific-cause mortality among the general population and the segment aged ≥75 years in Madrid. Ecological time-series study in the city of Madrid from January 01, 2004 to December 31, 2009. The dependent variable analysed was daily mortality due to natural (ICD-10:A00-R99), circulatory (ICD-10:I00-I99), and respiratory (ICD-10:J00-J99) causes in the population, both general and aged ≥75 years. The following independent and control variables were considered: a) daily mean PM and PM concentrations; b) maximum daily temperature; c) daily mean O and NO concentrations; d) advection of particulate matter from biomass combustion (), using a dichotomous variable and e) linear trend and seasonalities. We conducted a descriptive analysis, performed a test of means and, to ascertain relative risk, fitted a model using autoregressive Poisson regression and stratifying by days with and without biomass advection, in both populations. Of the 2192 days analysed, biomass advection occurred on 56, with mean PM and PM values registering a significant increase during these days. PM had a greater impact on organic mortality with advection (RRall ages = 1.035 [1.011-1.060]; RR ≥ 75 years = 1.066 [1.031-1.103]) than did PM without advection (RRall ages = 1.017 [1.009-1.025]; RR ≥ 75 years = 1.012 [1.003-1.022]). Among specific causes, respiratory-though not circulatory-causes were associated with PM on days with advection in ≥75 year age group. PM, rather than PM, were associated with an increase in natural cause mortality on days with advection of particulate matter from biomass combustion, particularly in the ≥75 year age group. [ABSTRACT FROM AUTHOR]

Severe factor VIII ( FVIII)-deficient patients with and without FVIII inhibitors cannot be distinguished using FVIII levels. The FVIII assay is sensitive to detect factor levels below 1%. While severe FVIII-deficient, non-inhibitor patients have FVIII < 1%, they may retain unmeasurable residual factor activity. In contrast, inhibitor patients have a FVIII antibody that presumably fully eliminates FVIII activity. It is unknown whether thromboelastography ( TEG) and thrombin generation assay ( TGA) can differentiate between patients with FVIII < 1% with and without the presence of FVIII inhibitors. The primary objective was to discern whether TEG and TGA could differentiate between severe FVIII-deficient patients with and without the presence of FVIII inhibitors. A secondary objective was to correlate TEG and TGA to annualized bleeding rates. This observational study performed TEG and TGA in healthy volunteers ( N = 15), severe FVIII-deficient ( N = 15) and severe FVIII-deficient patients with inhibitors ( N = 15). Kaolin-activated TEG was better at differentiating reaction time (31.3 vs. 120 min respectively, P = 0.004) and kinetics time (6.1 vs. 23.1 min respectively, P = 0.028) between the non-inhibitor and inhibitor patients. TEG activated by tissue factor in plasma-containing corn trypsin inhibitor failed to differentiate groups. The TGA failed to differentiate peak thrombin, endogenous thrombin potential and lag time between groups. There was no correlation between TEG and TGA with annualized bleeding rates. Kaolin-activated TEG, but not TGA, differentiated between severe FVIII-deficient patients with and without inhibitors. These assays did not find a correlation to annualized bleeding rate. [ABSTRACT FROM AUTHOR]

Invasive species display remarkable levels of ecophysiological plasticity, which supports colonization, population establishment and fitness across their introduction range. The red seaweed genus Asparagopsis comprises genetically homogeneous invasive species ( A. armata) and cryptic species complexes ( A. taxiformis sensu lato) consisting of invasive mitochondrial lineages introduced worldwide. The photosynthetic plasticity of Australian, Mediterranean and Hawaiian Falkenbergia stages (i.e. the tetrasporophytic stage) of A. taxiformis lineages 2, 3 and 4 and Mediterranean isolates of A. armata was assessed by challenging their photosynthetic performance at five different temperatures (12-26 °C). Our aim is to portray the photosynthetic profiles in relation to temperature for each of the aforementioned Asparagopsis OTUs. We additionally test the physiological response of A. taxiformis lineage 2 sampled within its invasive (Mediterranean Sea) and native range (Australia) to identify physiological features associated with invasive strains. Based on photosynthesis optima, Asparagopsis isolates were recovered into a tropical (NL2 and L4) and a temperate (AA, Il2 and L3) group that presented no differences in most photosynthetic parameters at the experimental temperatures, thus indicating a greater physiological plasticity. On the other hand, low I values together with an apparent lack of sensitivity in the photosynthetic response to changing temperatures were revealed for the Mediterranean lineage 2, indicative of adaptive benefits that likely support its invasive success compared to the rest of the genus. Our results represent a valuable resource to predict distributional shifts in some of the lineages and to anticipate control programs for lineage 3, potentially invasive. [ABSTRACT FROM AUTHOR]

Copyright of Revista Chilena de Cirugia is the property of Sociedad de Cirujanos de Chile and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Rapid identification of introduced seaweeds is crucial to support management and conservation decisions, especially when multiple cryptic lineages of high-profile invasive taxa occur sympatrically. The red seaweed genus Asparagopsis (Bonnemaisoniales, Rhodophyta) comprises two recognised morpho-species characterised by heteromorphic life cycles and presumably morphologically identical "Falkenbergia' tetrasporophyte stages: A. armata and A. taxiformis. Populations of the former were easily identified by the presence of distinctive harpoon-like braches on the gametophyte thalli. Four morphologically cryptic yet genetically distinct mitochondrial lineages of invasive nature were recognised within A. taxifortnis. We reported a morphological delineation of tetrasporophytes and gametophytes of A. sparagopsis, including cryptic lineages collected from the Mediterranean Sea and the Hawaiian Islands, where multiple Asparagopsis lineages were present. Vegetative anatomical characters of the tetrasporophytes were useful in differentiating A. armata from those of A. taxiformis as well as among tetrasporophyte isolates belonging to the four A. taxiformis lineages. In addition, these characters distinguished lineage 2 native range specimens (Hawaii) from the invasive specimens (Mediterranean Sea), which suggested high levels of morphological plasticity in the invasive taxon. We propose that the taxonomic status of the lineages within A. taxiformis needs to be revised. [ABSTRACT FROM AUTHOR]

We constructed the food webs of six Mediterranean streams in order to determine ecological generalities derived from analysis of their structure and to explore stabilizing forces within these ecosystems. Fish, macroinvertebrates, primary producers and detritus are the components of the studied food webs. Analysis focused on a suite of food web properties that describe species' trophic habits, linkage complexity and food chains. A great structural similarity was found in analyzed food webs; we therefore suggest average values for the structural properties of Mediterranean stream food webs. Percentage of omnivorous species was positively correlated with connectance, and there was a predominance of intermediate trophic level species that had established simple links with detritus. In short, our results suggest that omnivory and the weak interactions of detritivores have a stabilizing role in these food webs. [ABSTRACT FROM AUTHOR]

Summary The present work examines the temporal appearance and degree of activity of digestive enzymes of pancreatic and intestinal origin (amylase as well as neutral and alkaline proteases) together with the evolution of the ontogenic development of the intestine and pancreas during the first month of free-living (30 days post-hatch-[dph]) of the sturgeon Acipenser naccarii. In addition, the influence of exogenous live feeding with Artemia salina on the detection of digestive enzymes was studied. Shown are that in the first life stages of the A. naccarii, from the time of fertilisation to the juvenile stage, the following events related to its digestive physiology occurred: digestive enzymes were detected in the embryo stage within the egg, presumably related to the hatching gland; in the free-living embryo stage, opening of the mouth was at 10 dpf and protease and amylase digestive activities occurred due to an early differentiation of the pancreas and intestine (12-13 dpf). At this stage, digestive enzymatic activities are partly owing to the live feed offered before disappearance of the yolk reserves (14 dpf); the expulsion of the melanin plug and the appearance of a continuity of the digestion tract (16 dpf) together with the disappearance of the yolk reserves (17 dpf) mark the passage from the free-living embryo phase to the juvenile stage; finally, from the first month after hatching in this sturgeon species, there is a stabilisation in digestive amylase and protease activities together with a fully developed digestive structure. The contribution of enzymes from prey in the detection of enzymatic activities determined in the fish was beyond doubt; therefore these exogenous enzymes must also have a certain physiological importance. Subsequent work will be needed to clarify the importance of digestive processes of the exogenous enzyme pool from live feed as well as to assess the possibility of shortening the weaning period. [ABSTRACT FROM AUTHOR]

The peritoneal mesothelium exhibits a high regenerative ability. Peritoneal regeneration is concomitant with the appearance, in the coelomic cavity, of a free-floating population of cells whose origin and functions are still under discussion. We have isolated and characterized this cell population and we have studied the process of mesothelial regeneration through flow cytometry and confocal microscopy in a murine model lethally irradiated and reconstituted with GFP-expressing bone marrow cells. In unoperated control mice, most free cells positive for mesothelin, a mesothelial marker, are green fluorescent protein (GFP). However, 24 hrs after peritoneal damage, free mesothelin/ GFP cells appear in peritoneal lavages. Cultured lavage peritoneal cells show colocalization of GFP with mesothelial (mesothelin, cytokeratin) and fibroblastic markers. Immunohistochemical staining of the peritoneal wall also revealed colocalization of GFP with mesothelial markers and with procollagen-1 and smooth muscle α-actin. This was observed in the injured area as well as in the surrounding not-injured peritoneal surfaces. These cells, which we herein call peritoneal repairing cells (PRC), are very abundant 1 week after surgery covering both the damaged peritoneal wall and the surrounding uninjured area. However, they become very scarce 1 month later, when the mesothelium has completely healed. We suggest that PRC constitute a type of monocyte-derived cells, closely related with the tissue-repairing cells known as 'fibrocytes' and specifically involved in peritoneal reparation. Thus, our results constitute a synthesis of the different scenarios hitherto proposed about peritoneal regeneration, particularly recruitment of circulating progenitor cells and adhesion of free-floating coelomic cells. [ABSTRACT FROM AUTHOR]

This study describes the stomach development in the sturgeon Acipenser naccarii, focusing on its histoenzymatic and ultrastructural characteristics from hatching until the end of the juvenile phase, 1 month later. The study aims to assist the aquaculturist in identifying the best timing for the start of feeding and to select the appropriate food for each stage of A. naccarii development. At hatching, the anterior portion of the digestive system consists of a yolk sac with a large central yolk mass. The yolk mass is enclosed by differentiating endodermal epithelium. The most significant ultrastructural characteristics of the epithelium are the numerous supranuclear vacuoles containing protein and lipid yolk granules, dilated intercellular spaces, and filiform cytoplasmic projections related to the uptake of reserve material on the apical surface. Newly hatched eleuthero-embryos show optimal enzymatic activities at a pH of 1.5 and 3, which is probably related to the presence of hatching glands and the digestion of yolk components. During the free-embryo phase, the yolk sac epithelium undergoes a series of histological, ultrastructural, and functional modifications to form a cecal stomach with anatomical characteristics similar to those of juvenile specimens. Gastric glands emerge between 6 and 7 days post-hatching (PH), although the absence of secretion granules in their oxyntic-peptic cells indicates that the stomach is not yet functional. During the following days (the exotrophic period), development of the tubular-vesicular network is observed, and secreting granules occur in the cytoplasm of oxyntic-peptic cells until around day 35 after fertilization (day 27 PH), when acid protease enzymatic activity is again detected. These histological and enzymatic changes and the greater number and size of oxyntic-peptic cell secretion granules appear to be related to the gastric compartment ontogeny reaching functionality at this developmental stage. [ABSTRACT FROM AUTHOR]

When integrated weed management approaches are used, visual estimations of weed cover are commonly employed to quantify weed infestation levels in crops. This study assessed the reliability of visual estimation of weed cover, considering various factors which may influence the accuracy and consistency of human perception. Measurements were based on visual estimates of digital images acquired in maize fields. A total of 750 images were assessed independently by four experienced observers using three cover-abundance scales, varying the assessment date or the order in which the images were assessed. A good relationship was generally found between the visual estimates of weed cover and some objective parameters (actual weed cover, weed biomass). The analyses of reliability and repeatability showed no significant differences between the estimations performed by four different observers or by the same observer at different times, independently of the scale used. Nevertheless, the comparison between visual estimations performed by the observers and actual weed cover showed that observers tended to overestimate weed cover at low weed densities and underestimate it when densities were high. Although visual assessments of weed cover were relatively accurate to quantify weed infestation level, our results showed that human perception was not reliable enough to determine actual weed cover close to the class boundaries, both in the lower range (e.g. 5%, 10%) and in the middle range (e.g. 50%) of the scale. This may be a serious limitation for the use of visual methods in threshold-based weed management programmes. [ABSTRACT FROM AUTHOR]

The epicardium has recently been identified as an active and essential element of cardiac development. Recent reports have unveiled a variety of functions performed by the embryonic epicardium, as well as the cellular and molecular mechanisms regulating them. However, despite its developmental importance, a number of unsolved issues related to embryonic epicardial biology persist. In this review, we will summarize our current knowledge about ( i) the ontogeny and evolution of the epicardium, including a discussion on the evolutionary origins of the proepicardium (the epicardial primordium), ( ii) the nature of epicardial-myocardial interactions during development, known to be essential for myocardial growth and maturation, and ( iii) the contribution of epicardially derived cells to the vascular and connective tissue of the heart. We will finish with a note on the relationships existing between the primordia of the viscera and their coelomic epithelial lining. We would like to suggest that at least a part of the properties of the embryonic epicardium are shared by many other coelomic cell types, such that the role of epicardium in cardiac development is a particular example of a more general mechanism for the contribution of coelomic and coelomic-derived cells to the morphogenesis of organs such as the liver, kidneys, gonads or spleen. [ABSTRACT FROM AUTHOR]

We searched the Spanish and Portuguese pharmacovigilance databases for spontaneous case reports of heart rhythm disturbances associated with rupatadine and other new H1 antihistamines. Five cases were found involving patients treated with rupatadine (13.9% of all reports relating to this drug). In all five cases, the reaction started after exposure and resolved when the drug was discontinued. In two cases, rupatadine was the only medication being taken by the patient, and no other condition that could explain the heart rhythm disturbances was diagnosed. The reporting odds ratio was 3.2 (95% confidence interval, 1.0–10.5). The reporting rate was 2 cases per 100,000 patients treated per year (95% confidence interval, 0.4–6.0). These results suggest a causal relationship between rupatadine and heart rhythm disturbances.Clinical Pharmacology & Therapeutics (2009); 85, 5, 481–484 doi:10.1038/clpt.2008.269 [ABSTRACT FROM AUTHOR]

Tool path generation problem is one of the most complexes in computer aided manufacturing (CAM). Although some efficient algorithms have been developed to solve it, their technological dependency makes them efficient in only a limited number of cases. In the article we propose a model that will set apart the geometrical issues involved in the manufacturing process from the purely technology-dependent physical issues by means of a topological system. Presented in the paper there is a method for offsetting any kind of curve regardless of the machining technology (i.e., independent of any tool geometry: spherical, conical, toroidal and so on). Specifically, we use parametric cubic curves, which is one of the most general and popular models in CAD/CAM applications. [ABSTRACT FROM AUTHOR]

Colocalization of fluorescent signals in confocal microscopy is usually evaluated by inspecting merged images from different colour channels or by using commercially available software packages. We describe in this paper a simple method for assessment of nuclear localization of proteins in tissue sections through confocal immunolocalization, propidium iodide counterstaining and image analysis. Through a macro command developed for the public domain, Java-based softwareimagej, red, green, blue (RGB) images are automatically split in the red and green channels and a new image composed of the nonblack pixels coincident in both channels is created and inverted for better visualization. This method renders images devoid of both, extranuclear staining and background, thus emphasizing the nuclear signal. The resulting images can easily be used for comparison or quantification of the results. Given the simplicity of the technique and the worldwide diffusion of the software utilized, we think that this method could be useful in order to define standards of colocalization in confocal microscopy. [ABSTRACT FROM AUTHOR]

Circulatory systems of vertebrate and invertebrate metazoans are very different. Large vessels of invertebrates are constituted of spaces and lacunae located between the basement membranes of endodermal and mesodermal epithelia, and they lack an endothelial lining. Myoepithelial differentation of the coelomic cells covering hemal spaces is a frequent event, and myoepithelial cells often form microvessels in some large invertebrates. There is no phylogenetic theory about the origin of the endothelial cells in vertebrates. We herein propose that endothelial cells originated from a type of specialized blood cells, called amoebocytes, that adhere to the vascular basement membrane. The transition between amoebocytes and endothelium involved the acquisition of an epithelial phenotype. We suggest that immunological cooperation was the earliest function of these protoendothelial cells. Furthermore, their ability to transiently recover the migratory, invasive phenotype of amoebocytes (i.e., the angiogenic phenotype) allowed for vascular growth from the original visceral areas to the well-developed somatic areas of vertebrates (especially the tail, head, and neural tube). We also hypothesize that pericytes and smooth muscle cells derived from myoepithelial cells detached from the coelomic lining. As the origin of blood cells in invertebrates is probably coelomic, our hypothesis relates the origin of all the elements of the circulatory system with the coelomic wall. We have collected from the literature a number of comparative and developmental data supporting our hypothesis, for example the localization of the vascular endothelial growth factor receptor-2 ortholog in hemocytes of Drosophila or the fact that circulating progenitors can differentiate into endothelial cells even in adult vertebrates. [ABSTRACT FROM AUTHOR]

Presents the results of the National Youth Tobacco Survey conducted by the U.S. Centers for Disease Control and Prevention from 2002 to 2004. Data on the percentage of middle school students and their tobacco habit; Decline in the prevalence of youth smoking; Limitations of the study.

Objective To compare transvaginal ultrasound with the Bishop score in assessment of cervical ripening for choice of induction agent. Methods Eighty women were randomized to have preinduction cervical assessment for choice of induction agent based on either Bishop score or transvaginal ultrasound. The primary outcome measure was the percentage of women who were administered prostaglandin as a preinduction agent. The criteria for considering the cervix as unripe and thus for using prostaglandin were either a Bishop score < 6 or a cervical length > 30 mm with cervical wedging of < 30% of the total cervical length. Secondary outcome measures included interval to active phase, interval to delivery and rate of Cesarean section. Results While 85% of women received prostaglauidin in the Bishop score group, only 50% of them did in the transvaginal ultrasound group (P = 0.001). The interval to active phase, interval to delivery and rate of Cesarean section were similar in both groups. Conclusions With the suggested cut-off values of a Bishop score < 6 or a cervical length > 30 mm and wedging < 30%, the use of transvaginal ultrasound instead of Bishop score for preinduction cervical assessment to choose induction agent significantly reduces the need for intracervical prostaglandin treatment without adversely affecting the success of induction. [ABSTRACT FROM AUTHOR]

Baja California represents the northernmost reproductive area forLepidochelys olivacea. This region is characterized by its high temperature and low humidity. Thus, nest site selection plays an important role in reproductive success. To evaluate the factors affecting site selection for oviposition Las Barracas Beach, located in the south of the peninsula, was visited, from August to November 2000, in weekly periods. A density of 2.55 nests ha-1 was estimated from a total of 55 nests counted. A hatching success of 73.7% was observed, with 23.7% mortality and 2.5% of eggs without apparent development (eggs counted=4,031). On the day of oviposition, the relative surface humidity (between 0.75% and 1.75%) and temperature (32°C) preferred by the females for nest construction was determined at the nest site, as well as the mean distance between the nests and the high tide line for that day (17.65 m). Hatching success was affected by humidity and distance. In addition, hatching success was higher between 10 and 30 m above the high tide line measured on the day of oviposition (surface humidity ca. 1%). A total of 874 hatchlings were measured, with an average of 42.1 mm straight carapace length. Larger sizes were found in October and smaller ones in November. Generally speaking, the sizes found here were larger than those obtained in other areas. This is probably due to two factors: (1) the nests in Las Barracas were kept in situ, whereas in other areas nests are sometimes incubated artificially and (2) the nesting population of southern Baja California is different from the eastern Pacific population. [ABSTRACT FROM AUTHOR]

Modifications in the chloride (mitochondria-rich) and pavement cells of the gill epithelia of the Adriatic sturgeon Acipenser naccarii after their transfer under hypertonic environmental conditions (salinity 35) were examined by light and electron microscopy. In contrast to freshwater specimens, seawater-acclimated fish showed a marked increase in the number and size of chloride cells. Ultrastructural modifications included: presence of a slightly invaginated apical crypt, a darker cytoplasm, a more compact tubular system, a major increase in cisternae from Golgi apparatus stacks and flattened-out sacs with dilated ends that produced an increase in lateral and basal cell surfaces. All these changes indicated enhanced cellular activity. Pavement cells, which largely covered the chloride cells on the gill filament and lamella, exhibited a complex system of microridges on their apical surface. Typical features included numerous desmosomes that characterized the intercellular junction, and the presence in the apical cytoplasm of bundles of filaments and of electro-dense vesicles in freshwater fish or clear vesicles in seawater-acclimated animals. [ABSTRACT FROM AUTHOR]

Discusses the prevalence of cigarette use among racial/ethnic populations in the U.S. during 1999-2001. Primary racial/ethnic minority populations in the country; Data used for the "Tobacco Use Among U.S. Racial/Ethnic Minority Groups" report of the U.S. Surgeon General; Prevalence of cigarette use among youths.

Some features of the biological retina can be modelled by a 2-layer cellular neural network (CNN) composed of locally connected elementary nonlinear processors. In order to explore these complex spatiotemporal dynamics for image processing, a prototype chip has been designed and fabricated in a 0.5μm CMOS technology. Design challenges, trade-offs, the building blocks and the tests results for this system with 0.5×10[sup 6] transistors, most of them operating in analog mode, are presented in this paper. [ABSTRACT FROM AUTHOR]