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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]

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]

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]

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]

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]

The Wilms' tumour suppressor gene WT1 encodes a zinc-finger transcription factor which is essential for the development of kidney, gonads, spleen and adrenals. WT1-null embryos lack all of these viscerae and they also show a thin ventricular myocardium and unexpectedly die from cardiac failure between 13 and 15 days post coitum. We studied the localization of the WT1 protein in chick and quail embryos between stages HH18 and HH35. In early embryos, WT1 protein was located in specific areas of the coelomic mesothelium adjacent to the nephric ducts, the myocardium or the primordia of the endodermal organs (gut, liver and lungs). These mesothelial areas also showed localized expression of Slug, a zinc-finger transcription factor involved in epithelial-mesenchymal transitions. WT1+ mesenchymal cells were always found below the immunoreactive mesothelial areas, either forming a narrow band on the surface of the endodermal organs (gut, liver and lungs) or migrating throughout the mesodermal organs (mesonephros, metanephros, gonads, spleen and heart). In the developing heart, the invasion of WT1+ cells started at stage HH26, and all the ventricular myocardium was pervaded by these cells, presumably derived from the epicardium, at HH30. We suggest that WT1 is not required for the epithelial-mesenchymal transition of the coelomic mesothelium, but it might be a marker of the mesothelial-derived cells, where this protein would be acting as a repressor of the differentiation. [ABSTRACT FROM AUTHOR]

Slug is a transcription factor involved in processes such as the formation of mesoderm and neural crest, two developmental events that imply a transition from an epithelial to a mesenchymal phenotype. During late cardiac morphogenesis, mesenchymal cells originate from two epithelia – epicardial mesothelium and cushion endocardium. We aimed to check if Slug is expressed in these systems of epithelial-mesenchymal transition. We have immunolocated the Slug protein in the heart of quail embryos between Hamburger and Hamilton stages HH16 and HH30. In the proepicardium (the epicardial primordium), Slug was detected in most cells, mesothelial as well as mesenchymal. Slug immunoreactivity was strong in the mesenchyme of the endocardial cushions and subepicardium from its inception until HH24, but the immunoreactivity disappeared in later embryos. Only a small portion of the endocardial cells located in the areas of epithelial-mesenchymal transition (atrioventricular groove and outflow tract) were immunolabelled, mainly between HH16 and HH20. Endocardial cells from other cardiac segments were always negative, except for a transient, weak immunoreactivity that coincided with the development of the intertrabecular sinusoids of the ventricle. In contrast, virtually all cells of the epicardial mesothelium were immunoreactive until stage HH24. The mesenchymal cells that migrate to the heart through the spina vestibuli were also conspicuously immunoreactive. The myocardium was not labelled in the stages studied. Our results stress the involvement of Slug in the epithelial to mesenchymal transition. We suggest that Slug can constitute a reliable marker of the cardiac epithelial cells that are competent to transform into mesenchyme as well as a transient marker of the epithelial-derived mesenchymal cells in the developing heart. [ABSTRACT FROM AUTHOR]

The transfer of genetic information from the mitochondrion to the nucleus is thought to be still underway in higher plants. The mitochondrial genome of Arabidopsis thaliana contains only one rps14 pseudogene. In this paper we show that the functional gene encoding mitochondrial ribosomal protein S14 has been translocated to the nucleus. This gene transfer is a recent evolutionary event, which occurred within Cruciferae, probably after the divergence of Arabidopsis and Brassica napus. A 5′ extension of the rps14 reading frame encodes a presequence which, in vitro, targets the polypeptide to isolated mitochondria and is cleaved off during or after import. No intron was found at the junction of the targeting presequence with the mitochondrially derived sequence, which are directly connected. By contrast, a 90-bp intron, which is removed by splicing to give a mature poly(A)+mRNA of 0.9 kb, is located in the 3′ non-coding region. To our knowledge, this is the first report of an intron in such a position in a functional transferred gene in higher plants, and suggests that exon shuffling may have been involved in the acquisition of elements necessary for expression in the nucleus. Putative roles of this intron in polyadenylation and enhancement of gene expression are discussed. [ABSTRACT FROM AUTHOR]

Examines the photosynthetic acclimation and biochemical responses of Gelidium sesquipedal cultured in chemostats. Effect of the quality of light and photon-fluence rate; Indications of the changes in C-partitioning between carbon compounds and organic nitrogen compounds; Mobilization and accumulation of carbon in the algae.

This paper is devoted to the analysis of the large time behavior of the solutions of the Anderson parabolic problem: when the potential ξ( x) is a homogeneous ergodic random field on ℝ. Our goal is to prove the asymptotic spatial intermittency of the solution and for this reason, we analyze the large time properties of all the moments of the positive solutions. This provides an extension to the continuous space ℝ of the work done originally by Gärtner and Molchanov in the case of the lattice ℤ. In the process of our moment analysis, we show that it is possible to exhibit new asymptotic regimes by considering a special class of generalized Gaussian fields, interpolating continuously between the exponent 2 which is found in the case of bona fide continuous Gaussian fields ξ( x) and the exponent 3/2 appearing in the case of a one dimensional white noise. Finally, we also determine the precise almost sure large time asymptotics of the positive solutions. [ABSTRACT FROM AUTHOR]

Rye plants carrying B chromosomes with different nuclear and cytoplasmic constitutions have been analyzed at first pollen mitosis. No differences of B chromosome behaviour have been detected. It has been concluded that non-disjunction and preferential distribution are processes controlled by Bs themselves. At second pollen anaphase, B laggards have been observed. Both non-disjunction and B laggards occurred with higher frequency in younger anthers. [ABSTRACT FROM AUTHOR]

The meiotic behaviour of hybrids between Secale cereale carrying B chromosomes and S. vavilovii has been studied in order to estimate the effects of B chromosomes on hybrid meiotic pairing. The possible effect of Bs on the meiotic pairing of the offspring from backcrosses with S. vavilovii has been studied also. The results obtained clearly indicate that no detectable differences existed in chromosome pairing of hybrids with or without B chromosomes. The hypothetical existence of epistatic genes on cereale genome masking the effect of Bs has been rejected after the results obtained in backcrosses. Therefore, lack of qualitative genes controlling interspecific pairing on rye B chromosomes has been concluded. A quantitative effect of B chromosomes was detected only when they were in alien cytoplasm. [ABSTRACT FROM AUTHOR]

We prove that the Schrödinger operator H=− d/ dx+ V( x)+ F· x has purely absolutely continuous spectrum for arbitrary constant external field F, for a large class of potentials; this result applies to many periodic, almost periodic and random potentials and in particular to random wells of independent depth for which we prove that when F=0, the spectrum is almost surely pure point with exponentially decaying eigenfunctions. [ABSTRACT FROM AUTHOR]

By using Agmon's geodesic ideas to single out particular regions in path space, we obtain optimal lower bounds on the leading behavior for the fall off of the ground state of multiparticle system. [ABSTRACT FROM AUTHOR]

Bochdalek’s hernia is a congenital defect of the diaphragm that occurs predominantly in children. Perforation or necrosis of the involved organ is a feared complication and surgical repair constitutes the gold standard of treatment. We present a case of a 42-year-old female patient who presented with a 3-month history of left-upper-quadrant abdominal pain, nausea, tachycardia, and early postprandial vomit. Physical exploration was remarkable for audible peristalsis in the left hemithorax. Total white blood count was elevated and chest X-rays showed images of intestines in the left hemithorax. Tomography with double contrast reported left colon herniated to thorax. Left thoracoscopy was practised, finding a Bochdalek’s hernia with presence of herniated descendent colon with a necrotic area, which was perforated and sealed. The herniated content was returned back in place, the diaphragmatic defect was corrected, and colostomy by laparoscopy was simultaneously performed. Her postoperative recovery was uneventful and she was discharged from the hospital. Combined thoracoscopy and laparoscopic surgery is effective in complicated cases of Bochdalek’s hernia in adults, lessening surgical trauma and postsurgical morbidity. [ABSTRACT FROM AUTHOR]

To contribute to knowledge on the significance of B chromosomes in rye populations, a component of fertility has been estimated by a comparative study of germination and growth of pollen tubes in plants with and without B chromosomes. The highest percentage germination of pollen and mean speed of pollen tube growth was shown by 14 + 2B plants, followed by normal plants. Observations of first pollen mitosis indicated that in most cases the chromatid constitution of the tube nucleus was the same in 14, 14 + 1 and 14 + 2B plants. In contrast, the mean growth rate of pollen tubes differed significantly among the three cases. From these data it seems that the determination of germination ability and pollen tube growth depends on the sporophyte and is related to the number of Bs carried by the plant. [ABSTRACT FROM AUTHOR]