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A new species of the genus Plagiorhynchus Lühe, 1911 from the intestine of the long-billed curlew (Numenius americanus) from northern Mexico is described. Plagiorhynchus (Plagiorhynchus) aznari n. sp. is morphologically distinguished from other congeneric species from the Americas by having a trunk expanded anteriorly and a cylindrical proboscis, armed with 19 longitudinal rows of hooks, with 14–15 hooks each row. Nearly complete sequences of the small subunit and large subunit of the nuclear ribosomal DNA of the new species were determined and compared with available sequences from GenBank. Phylogenetic analyses inferred from the two molecular markers consistently showed that P. (Plagiorhynchus) aznari n. sp. is closely related to P. (Plagiorhynchus) allisonae, and this clade is sister to a clade formed by P. (Prosthorhynchus) transversus and P. (Prosthorhynchus) cylindraceus from Plagiorhynchidae. The new species represents the second record of the genus in Mexico and the fourth species in the Americas. The phylogenetic relationships among the members of the order Polymorphida in this study provide significant insights into the evolution of ecological associations between parasites and their definitive hosts. Our analyses suggest that the colonization of marine mammals, fish-eating birds and waterfowl in Polymorphidae might have occurred independently, from a common ancestor of Centrorhynchidae and Plagiorhynchidae that colonized terrestrial birds and mammals.
This is a copy of the slides presented at the meeting but not formally written up for the volume.
The growth of heterostructures combining oxide materials is a new strategy to design novel artificial multifunctional materials with interesting behaviors ruled by the interface. There has been increasing interest in heterostructures combining oxides with different functionalities and ground states competing at the interface. In structures involving oxides, interfaces are especially complex and various factors like interface disorder and roughness, epitaxial strain, polarity mismatch etc., are responsible for modified properties at the interface over nanometer length scales. In this presentation we will focus on cuprate / manganite heterostructures made of YBa2Cu3O7 (YBCO) and La1-xCaxMnO3 (LCMO), where the Ca content is varied over a wide range. The manganite grows epitaxially on the superconductor with different degrees of strain depending on the Ca content. For x=0.3 the manganite is ferromagnetic what causes a strong depression of the superconducting order parameter at the YBCO side. Interestingly, there is also a depression of the ferromagnetic moment at the interface suggesting charge transfer (electrons) from the manganite into the YBCO. This is confirmed growing superlattices combining YBCO with the parent manganite compound with x=0, which is nominally an AF insulator. Actually, for LMO thickness below 6 unit cells (2,4 nm) the layers are non magnetic and insulating as expected. However, above this LMO thickness (6 unit cells) we show that superconductivity is strongly suppressed and ferromagnetism is induced at the interface providing a strong evidence for the charge transfer scenario. The control of layer bulk doping by charge transfer at the interface opens new possibilities of tailoring the electronic states at the interface for the design of novel functionalities and devices. Work supported by CICYT MAT2005 06024 C02-02 and DOE.
Cephalopods are important prey in the diet of top predators, such as marine mammals and seabirds. However, detailed information on their trophic relationships in the Patagonian marine ecosystem is scarce, including those cephalopod species with commercial interest. The aims of this study were to evaluate the composition of the cephalopod component in the diet of Otaria byronia and determine the habitat use and trophic levels of their main cephalopod prey by measuring the stable isotopic signature of cephalopod beaks. Between May 2005 and February 2009, fresh faecal samples were collected from two sea lions rookeries in San Matias Gulf. Cephalopods occurred in 39.4% of the 1112 samples collected during the whole period of study. The dominant prey species was Octopus tehuelchus, which occurred in 45.8% of scats containing cephalopod remains, and represented 58.7% in terms of numerical abundance and 52.0% in mass of cephalopods consumed. The second species most consumed was the myopsid Doryteuthis gahi. The significant higher δ15N values of O. tehuelchus beaks in comparison with those of D. gahi showed that these two species have different trophic levels while occupying similar habitat (δ13C values) in neritic waters of the Patagonian shelf.
The Centro de Laseres Pulsados in Salamanca, Spain has recently started operation phase and the first user access period on the 6 J 30 fs 200 TW system (VEGA 2) already started at the beginning of 2018. In this paper we report on two commissioning experiments recently performed on the VEGA 2 system in preparation for the user campaign. VEGA 2 system has been tested in different configurations depending on the focusing optics and targets used. One configuration (long focal length
cm) is for underdense laser–matter interaction where VEGA 2 is focused onto a low density gas-jet generating electron beams (via laser wake field acceleration mechanism) with maximum energy up to 500 MeV and an X-ray betatron source with a 10 keV critical energy. A second configuration (short focal length
cm) is for overdense laser–matter interaction where VEGA 2 is focused onto a
thick Al target generating a proton beam with a maximum energy of 10 MeV and temperature of 2.5 MeV. In this paper we present preliminary experimental results.
The clinical and pathologic characterisation of two fatal cases of tick-borne rickettsiosis in rural (El Valle) and urban (City of Panama) Panama are described. Clinical and autopsy findings were non-specific, but the molecular analysis was used to identify Rickettsia rickettsii in both cases. No ticks were collected in El Valle, while in the urban case, R. rickettsii was detected in Rhipicephalus sanguineus s.l., representing the first molecular finding in this tick in Panama and Central America.
Information relating the severity of cognitive decline to the fall risk in institutionalized older adults is still scarce. This study aims to identify potential fall risk factors (medications, behavior, motor function, and neuropsychological disturbances) depending on the severity of cognitive impairment in nursing home residents.
A total of 1,167 nursing home residents (mean age 81.44 ± 8.26 years; 66.4% women) participated in the study. According to the MEC, (the Spanish version of the Mini-Mental State Examination) three levels of cognitive impairment were established: mild (20–24) “MCI”, moderate (14–19) “MOCI”, and severe (≤14) “SCI”. Scores above 24 points indicated the absence cognitive impairment (NCI). Information regarding fall history and fall risk during the previous year was collected using standardized questionnaires and tests.
Sixty falls (34%) were registered among NCI participants and 417 (43%) among people with cognitive impairment (MCI: 35%; MOCI: 40%; SCI: 50%). A different fall risk model was observed for MCI, MOCI, SCI, and NCI patients. The results imply that the higher the level of cognitive impairment, the greater the number of falls (F1,481 = 113.852; Sig = 0.015), although the level of significance was not maintained when MOCI and SCI participants were compared. Depression, neuropsychiatric disturbances, autonomy constraints in daily life activity performance, and low functional mobility were factors closely associated with fall risk.
This study provides evidence indicating that fall risk factors do not hold a direct correlation with the level of cognitive impairment among elderly nursing home care residents.
The luminosity profiles perpendicular to the bar of the galaxy NGC 7479 display “shoulders”, which are observationally identified as an increase in the brightness profile (see Figure 1, right). In the literature (see e.g. Buta 1986), the presence of these features in other barred spirals has been reported. The “shoulders” have been attributed to annular structures resulting from the presence of a bar (Schwarz 1981, 1984, 1985), appearing at the OLR. Their stability and the precise modelling depends on the structural parameters of the bar. We attempt to test the plausibility of this theoretical interpretation using 2D photometry of the barred galaxy NGC 7479. The key parameter is the corotation radius (CR), defined as the galactocentric distance at which the gas and the shock wave corotate. From the CR all other Lindblad resonances can be obtained. Some of the techniques used to derive the CR are:
Here we present a study of the structural components of the barred galaxy NGC 5850 using U, B and I photometry. After subtracting a bulge+disk model from the observed image, we obtain the bar and other non-axisymmetric structures. We determine the position of the ILR from the ellipticity and position angle profiles of the isophotes.
We present surface photometry in U BV RI passbands of the barred spiral galaxies NGC 7479 and NGC 7606, for which observations were obtained at the Cassegrain focus of the 2.5-m Isaac Newton Telescope at La Palma. Data are presented in the form of images and mean radial profiles from azimuthal fits of ellipses, giving the luminosity, ellipticities and position angles of the isophotes as functions of the galactocentric radii. Images in I-band are shown in Figure 1 of NGC 7479 (left) and NGC 7606 (right). These belong to a sample of galaxies with moderate circumnuclear starbursts. We are analyzing their structure to study the effects of departures from an axisymmetric potential for the dynamics of a galaxy. One objective of this study is to make a three-dimensional model of the bar and bulge using the method of photometric inversion. The sample consists of 27 spiral galaxies with and without a bar.
From September 2000 to September 2001 the concentration of chlorophyll a, and the abundance and composition of the phytoplanktonic community was studied in a neritic station of the Mallorca Channel (Western Mediterranean). Sampling was performed approximately every 12 days. Chlorophyll a concentration and phytoplankton abundance reached maxima of 1.79 μg L−l and 352 cells mL−1, respectively. It was a relatively productive period, as a result of the high convective mixing in winter and the prevalence of northern waters during most of the cycle. Phytoplankton proliferations (chlorophyll a concentration >1 mg L−1) were detected in January, February, March and June. Those blooms mainly happened under the influence of northern waters, with the exception of the February proliferation, when mixing conditions were found. During bloom conditions it highlights the presence of coccolithophores as proliferation precursors. During no-bloom situations the phytoplankton community was mainly constituted by nanoplanktonic flagellated forms. The Winter Mixing period was dominated by different groups of nanoflagellates, including coccolithophores, undetermined flagellates and dinoflagellates. However, in the most oligotrophic conditions (from April until November) dinoflagellates were clearly dominant, except in the DCM in summer where diatoms prevailed.
Cortical thickness measurement offers an index of brain development processes. In healthy individuals, cortical thickness is reduced with increasing age and is related to cognitive decline. Cortical thinning has been reported in schizophrenia. Whether cortical thickness changes differently over time in patients and its impact on outcome remain unanswered.
Data were examined from 109 patients and 76 healthy controls drawn from the Santander Longitudinal Study of first-episode schizophrenia for whom adequate structural magnetic resonance imaging (MRI) data were available (n = 555 scans). Clinical and cognitive assessments and MRIs were acquired at three regular time points during a 3-year follow-up period. We investigated likely progressive cortical thickness changes in schizophrenia during the first 3 years after initiating antipsychotic treatment. The effects of cortical thickness changes on cognitive and clinical variables were also examined along with the impact of potential confounding factors.
There were significant diagnoses × scan time interaction main effects for total cortical thickness (F1,309.1 = 4.60, p = 0.033) and frontal cortical thickness (F1,310.6 = 5.30, p = 0.022), reflecting a lesser thinning over time in patients. Clinical and cognitive outcome was not associated with progressive cortical changes during the early years of the illness.
Cortical thickness abnormalities do not unswervingly progress, at least throughout the first years of the illness. Previous studies have suggested that modifiable factors may partly account for cortical thickness abnormalities. Therefore, the importance of implementing practical actions that may modify those factors and improve them over the course of the illness should be highlighted.
Early investigation of travel-related cases in an outbreak of an emerging infectious disease can provide useful information to epidemiologists to characterize the exposure, while they may differ in demographic profiles from cases reported in the country where the outbreak has occurred. During the spring 2011 E. coli outbreak in Germany, we proposed a methodological approach to collect a minimal set of demographic and clinical data that are relatively easy to obtain and available at an early stage of an outbreak investigation. Ninety-eight STEC O104 travel-related cases were reported in a survey by seven EU countries, Switzerland, Canada and the USA. We found a mean incubation period (n = 50) of 8·5 days, which confirmed previous estimations communicated by the Robert Koch Institute. No significant association was found between the duration of the incubation period and possible demographic and clinical factors, although the older the age, the shorter the incubation period that was observed. Such approach and observations are informative for further investigations of outbreaks of enterohaemorrhagic E. coli or other emerging infectious diseases.
To date, it is unclear whether chemical order (or disorder) is in any way connected to double exchange, electronic phase separation, or charge ordering (CO) in manganites. In this work, we carry out an atomic resolution study of the colossal magnetoresistant manganite La2−2xSr1+2xMn2O7 (LSMO). We combine aberration-corrected electron microscopy and spectroscopy with spectroscopic image simulations, to analyze cation ordering at the atomic scale in real space in a number of LSMO single crystals. We compare three different compositions within the phase diagram: a ferromagnetic metallic material (x=0.36), an insulating, antiferromagnetic charge ordered (AF-CO) compound (x=0.5), which also exhibits orbital ordering, and an additional AF sample (x=0.56). Detailed image simulations are essential to accurately quantify the degree of chemical ordering of these samples. We find a significant degree of long-range chemical ordering in all cases, which increases in the AF-CO range. However, the degree of ordering is never complete nor can it explain the strongly correlated underlying ordering phenomena. Our results show that chemical ordering over distinct crystallographic sites is not needed for electronic ordering phenomena to appear in manganites, and cannot by itself explain the complex electronic behavior of LSMO.