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The Mangalitza pig breed has suffered strong population reductions due to competition with more productive cosmopolitan breeds. In the current work, we aimed to investigate the effects of this sustained demographic recession on the genomic diversity of Mangalitza pigs. By using the Porcine Single Nucleotid Polymorphism BeadChip, we have characterized the genome-wide diversity of 350 individuals including 45 Red Mangalitza (number of samples; n=20 from Hungary and n=25 from Romania), 37 Blond Mangalitza, 26 Swallow-belly Mangalitza, 48 Blond Mangalitza × Duroc crossbreds, 5 Bazna swine, 143 pigs from the Hampshire, Duroc, Landrace, Large White and Pietrain breeds and 46 wild boars from Romania (n=18) and Hungary (n=28). Performance of a multidimensional scaling plot showed that Landrace, Large White and Pietrain pigs clustered independently from Mangalitza pigs and Romanian and Hungarian wild boars. The number and total length of ROH (runs of homozygosity), as well as FROH coefficients (proportion of the autosomal genome covered ROH) did not show major differences between Mangalitza pigs and other wild and domestic pig populations. However, Romanian and Hungarian Red Mangalitza pigs displayed an increased frequency of very long ROH (>30 Mb) when compared with other porcine breeds. These results indicate that Red Mangalitza pigs underwent recent and strong inbreeding probably as a consequence of severe reductions in census size.
The Total Solar Irradiance (TSI), which is the total radiation arriving at Earth's atmosphere from the Sun, is one of the most important forcing of the Earths climate. Measurements of the TSI have been made employing instruments on board several space-based platforms during the last four solar cycles. However, combining these measurements is still challenging due to the degradation of the sensor elements and the long-term stability of the electronics. Here we describe the preliminary efforts to design an absolute radiometer based on the principle of electrical substitution that is under development at Brazilian's National Institute for Space Research (INPE).
Oil palm plantations are rapidly expanding in tropical areas, although the nature of the impacts on the functional roles of the different species in the ecosystem is poorly understood. The present study is the first assessment of how oil palm affects the functional diversity of birds in the Brazilian Amazon and tests the hypothesis that converting forest to oil palm decreases functional diversity of bird communities, selecting species more tolerant to environmental disturbances. We conducted point counts to survey bird communities in 16 plots in the eastern Amazon. We sampled 32 points in riparian forest, 128 in oil palm and 160 in forested habitats. To test whether the conversion of forest into oil palm plantations affects functional diversity of birds we calculated the FD (Functional Diversity) and FRic (Functional Richness) indices. To examine whether oil palm plantations select species functionally more similar than expected by chance we used a null model (SES.FD). FD was significantly higher in the forest plots in comparison with riparian forests and oil palm, and lower in oil palm when compared with riparian forests. FRic, in turn, was greater in forest plots than in oil palm and in riparian forest. These results show that the conversion of forested areas to oil palm represents a great loss of functional strategies. The SES values indicate that in forested habitats bird communities tend to be functionally clustered while in the oil palm they are functionally overdispersed. The functional traits most affected by oil palm were those associated with diet and foraging stratum. In short, oil palm plantations reduced functional diversity of birds, although the presence of riparian forests within the plantations and the fragments of forest adjacent are extremely important for the maintenance of ecosystem services.
This paper reports an unusual green pigment, brochantite (Cu4(SO4)(OH)6), on 16th-century Portuguese-Flemish paintings, attributed to the Master Frei Carlos workshop. This green mineral is usually identified as an impurity or alteration product in the green pigments verdigris (Cu(CH3COO)2nCu(OH)2) or malachite (CuCO3 Cu(OH)2). However, after thorough investigation with a broad range of analytical techniques, it became clear that, in this case, brochantite was applied as a pigment. The abundance, pigment granulometry, and pigment morphology suggest intentional use by this Portuguese-Flemish Master as a natural pigment rather than its accidental use as an alteration product. This seems to be a distinguishable feature to other painters (Flemish and Portuguese) working in Portugal at the beginning of the 16th century.
The multi-analytical study of these easel paintings was first performed by physical imaging techniques and material characterization was carried out by optical microscopy, micro-Fourier-transform infrared-spectroscopy, micro-Raman spectroscopy, scanning electron microscopy coupled with energy dispersive X-ray spectrometry, and micro-X-ray diffraction analysis (XRD).
This paper analyses the population dynamics, growth and feeding ecology of Dicentrarchus labrax in order to gain a better understanding of its present role in the western Dutch Wadden Sea ecosystem. Otolith analysis showed that the population is mostly comprised of individuals aged 3–5 years old and between 20 and 45 cm in length. In autumn, 0-group juveniles are also an important part of the population. Both juveniles and adults use the area as a feeding ground exhibiting an opportunistic feeding strategy that relies on available prey, especially the brown shrimp Crangon crangon. Stomach content analysis and nitrogen stable isotope analysis showed an ontogenetic shift towards piscivory and a general decrease in the dominance of invertebrates with increasing size. Over the last 50 years, large between-year fluctuations in D. labrax abundance have been observed with an underlying increasing trend from about 1990 until 2007 followed by a subsequent decline. Spring abundance showed significant relationships with temperature and salinity while autumn abundance was only related to temperature. Spring and autumn D. labrax abundance were also strongly related to abundance of brown shrimp C. crangon prey. Long-term trends in temperature and salinity in the area suggest that environmental conditions for juvenile growth have become optimal, resulting in increased abundance since the mid-1980s. Continued monitoring of the dynamics of this species in the Dutch Wadden Sea is important to understand and anticipate the effects of climate change on the D. labrax population and its role in the local food web.
The dual risk model assumes that the surplus of a company decreases at a constant rate over time and grows by means of upward jumps, which occur at random times and sizes. It is said to have applications to companies with economical activities involved in research and development. This model is dual to the well-known Cramér-Lundberg risk model with applications to insurance. Most existing results on the study of the dual model assume that the random waiting times between consecutive gains follow an exponential distribution, as in the classical Cramér-Lundberg risk model. We generalize to other compound renewal risk models where such waiting times are Erlang(n) distributed. Using the roots of the fundamental and the generalized Lundberg's equations, we get expressions for the ruin probability and the Laplace transform of the time of ruin for an arbitrary single gain distribution. Furthermore, we compute expected discounted dividends, as well as higher moments, when the individual common gains follow a Phase-Type, PH(m), distribution. We also perform illustrations working some examples for some particular gain distributions and obtain numerical results.
Glutamine may be a precursor for NO synthesis, which may play a crucial role in bacterial translocation (BT). The goal of the present study was to investigate the potential effects of glutamine on BT and the immunological response in an experimental model of NO synthase inhibition by NG-nitro-L-arginine methyl ester (l-NAME). Mice were randomly assigned to four groups: sham; intestinal obstruction (IO); IO+500 mg/kg per d glutamine (GLN); IO+GLN plus 10 mg/kg per d l-NAME (GLN/LN). The groups were pretreated for 7 d. BT was induced by ileal ligation and was assessed 18 h later by measuring the radioactivity of 99mTc-Escherichiacoli in the blood and organs. Mucosal damage was determined using a histological analysis. Intestinal permeability (IP) was assessed by measuring the levels of 99mTc-diethylenetriaminepentaacetic acid in the blood at 4, 8 and 18 h after surgery. IgA and cytokine concentrations were determined by ELISA in the intestinal fluid and plasma, respectively. BT was increased in the GLN/LN and IO groups than in the GLN and sham groups. IP and intestinal mucosa structure of the sham, GLN and GLN/LN groups were similar. The GLN group had the highest levels of interferon-γ, while IL-10 and secretory IgA levels were higher than those of the IO group but similar to those of the GLN/LN group. The present results suggest that effects of the glutamine pathway on BT were mediated by NO. The latter also interferes with the pro-inflammatory systemic immunological response. On the other hand, IP integrity preserved by the use of glutamine is independent of NO.
Tributyrin (TBT) is a TAG composed of three butyric acids that has beneficial effects on ulcerative colitis due to its trophic, anti-inflammatory, pro-apoptotic and anti-carcinogenic properties. The goal of the present study was to evaluate the efficacy and mechanisms of action of TBT supplementation in the prevention of mucosal damage in experimental colitis. Mice received either a control diet or a TBT-supplemented diet for 15 d. Colitis was induced by dextran sodium sulphate administration during the last 7 d. Mucosal damage and the activation of immune cells and cytokines were determined by histological score, flow cytometry and ELISA. Leucocyte rolling and adhesion were assessed by intravital microscopy. Oxidative stress was determined by monitoring hydroperoxide concentration and evaluating superoxide dismutase (SOD) and catalase activities. Intestinal permeability was analysed using diethylenetriaminepentaacetate acid (99mTcDTPA). Compared with the colitis group, the animals in the colitis+TBT group had reduced mucosal damage and neutrophil and eosinophil mucosal infiltration, which were associated with a higher percentage of regulatory T cells (Treg) and higher levels of transforming growth factor β and IL-10 in the lamina propria. The level of in vivo leucocyte adhesion in the colon microvasculature was reduced after TBT supplementation. A lower level of hydroperoxide and higher levels of SOD and catalase activities were associated with TBT supplementation. TBT-supplemented mice showed reduced intestinal permeability to the levels intermediate between the control and colitis groups. In conclusion, the present results show that TBT has positive effects on colonic restructuring in experimental colitis. Additionally, TBT supplementation changes the immune response by controlling inflammation and regulating the expression of anti-inflammatory cytokines and Treg.
Genetic parameters for test-day milk flow (TDMF) of 2175 first lactations of Holstein cows were estimated using multiple-trait and repeatability models. The models included the direct additive genetic effect as a random effect and contemporary group (defined as the year and month of test) and age of cow at calving (linear and quadratic effect) as fixed effects. For the repeatability model, in addition to the effects cited, the permanent environmental effect of the animal was also included as a random effect. Variance components were estimated using the restricted maximum likelihood method in single- and multiple-trait and repeatability analyses. The heritability estimates for TDMF ranged from 0.23 (TDMF 6) to 0.32 (TDMF 2 and TDMF 4) in single-trait analysis and from 0.28 (TDMF 7 and TDMF 10) to 0.37 (TDMF 4) in multiple-trait analysis. In general, higher heritabilities were observed at the beginning of lactation until the fourth month. Heritability estimated with the repeatability model was 0.27 and the coefficient of repeatability for first lactation TDMF was 0.66. The genetic correlations were positive and ranged from 0.72 (TDMF 1 and 10) to 0.97 (TDMF 4 and 5). The results indicate that milk flow should respond satisfactorily to selection, promoting rapid genetic gains because the estimated heritabilities were moderate to high. Higher genetic gains might be obtained if selection was performed in the TDMF 4. Both the repeatability model and the multiple-trait model are adequate for the genetic evaluation of animals in terms of milk flow, but the latter provides more accurate estimates of breeding values.
This paper reports on the incorporation and validation of a microagitation system based on a piezoelectric polymer, Poly(vinylidene fluoride) in its beta phase, β-PVDF, in a fully-integrated disposable lab-on-a-chip for point-of-care testing and monitoring of biochemical parameters in biological fluids. The lab-on-a-chip concept offers a novel approach for clinical analyses, especially in biological fluids analyses, due to its portability, ensuring that the analysis can be performed at any location with quick results. Its microagitation system performance was successfully demonstrated by quantitative measurements of uric acid in human urine, though other molecules or biological fluids can be also measured. The optimization tests prove that it is possible to use lower frequencies than resonance with no major changes in the mixing process. The effect of area and location within the lab-on-a-chip of the microagitation system was also considered.
Binary brown dwarfs are important because their dynamical masses can be determined in a model-independent way. If a main sequence star is also involved, the age and metallicity for the system can be determined, making it possible to break the sub-stellar mass-age degeneracy. The most suitable benchmark system for intermediate age T dwarfs is ε Indi Ba,b, two T dwarfs (spectral types T1 and T6; McCaughrean et al. (2004)) orbiting a K4.5V star, ε Indi A, at a projected separation of 1460AU. At a distance of 3.6224pc (HIPPARCOS distance to ε Indi A; van Leeuwen (2007)), these are the closest brown dwarfs to the Earth, and thus both components are bright and the system is well-resolved. The system has been monitored astrometrically with NACO and FORS2 on the VLT since June 2004 and August 2005, respectively, in order to determine the system and individual masses independent of evolutionary models. We have obtained a preliminary system mass of 121±1MJup. We have also analysed optical/near-IR spectra (0.6-5.0μm at a resolution up to R~5000; King et al. (2009)) allowing us to determine bolometric luminosities, compare and calibrate evolutionary and atmospheric models of T dwarfs at an age of 4-8Gyr.
Proteins associated with the schistosome tegument are of great importance for the development of new intervention strategies since they may be exposed on the surface of the parasite. Herein, we have isolated a cDNA clone encoding for the Schistosoma mansoni SmIg and its recombinant protein was tested as a potential vaccine candidate. Initially, its amino acid sequence was analysed by bioinformatics and shown to possess an N-terminal signal peptide, a C-terminal transmembrane helix, 4 glycosylation sites, an immunoglobulin conserved domain and 73% similarity with a hypothetical S. japonicum protein of unknown function. SmIg was produced by E. coli as a recombinant protein (rSmIg) and its protective effectiveness was evaluated against S. mansoni infection with 100 cercariae in a murine model. Mice immunized with rSmIg induced an immune response characterized by dominant IgG1 isotype and significant levels of IFN-γ, TNF-α, IL-10 and IL-4. Although immunogenic, the recombinant vaccine failed to induce worm burden reduction when compared to the infected control group. However, rSmIg-immunized mice had significant reductions of liver granuloma volume and fibrosis content by 31·8% and 49%, respectively. In conclusion, SmIg is a new tegument protein from S. mansoni that plays an important role in reducing pathology induced by parasite infection.
While investigating isolated or agglomerates of treated Vaccinia
virus intracellular mature (IMV) particles in atomic force microscopy
(AFM) equipment we noticed that in some occasions the enveloped
particles had been totally disrupted, with the interior being spread
around. We have also observed in these samples what appear to be some
rather intriguing viral surface interactions. Instead of showing a clear
division between individual virions the particles seem to be continuous
at the interfaces that show coalescence. In order to understand what was
happening we focused our attention on the analysis of the images of the
interface between virions particles, trying to find out what was the
explanation for such type of particle surface interaction and in which
conditions it would take place.
After the commissioning of its vacuum degasser (RH-KTB) in 1998, Companhia
Siderúrgica de Tubarão (CST) started the development of slabs to be applied as high
value added products, such as ultra-low carbon steel grades (ULC) for automotive
applications. For this purpose, it was necessary to promote the development of a quality
design system, encompassing all stages of steel manufacturing and slab casting at CST,
as well as the steps of finishing rolling and coating. This paper describes the
methodology for development of ULC steels at CST together with the company Sollac-Lorraine
emphasizing the interchange of technical information aiming the continuous improvement.
In this way, the results of the end product surface inspection are correlated with
the technical parameters of steel production, including the quality events of steel
refining and casting, as well as the slab conditioning.
We studied risk factors for nosocomial infections among 500 critically ill children who were admitted to a pediatric intensive care unit from August 1994 through August 1996 and who were prospectively followed until death, transfer, or discharge. Age, gender, postoperative state, length of stay, device-utilization ratio, pediatric risk of mortality score, and total parenteral nutrition were the risk factors studied. Through multivariate analysis, we identified three independent risk factors for nosocomial infection: device-utilization ratio (odds ratio [OR], 1.6; 95% confidence interval [CI95], 1.10-2.34), total parenteral nutrition (OR, 2.5; CI95, 1.05-5.81) and length of stay (OR, 1.7; CI95, 1.31-2.21).
Transmission electron microscopy observations were conducted on some zwitterionic polymers. Our observations were concentrated on the morphology of the solid state of poly (4-vinyl pyridine-sulfopropyl bctaines), with different degrees of quaternization. Among the morphological features, a microstructure arising from aggregated regions in the range of 50 to 200 Å is observed. Quite striking is the fact that this structure is absent in the micrographs for the base polymer, indicating that the aggregates are due to the interactions of the ion pairs of the polyzwitterions, as in the ionomer case. It is also found that the density of the aggregates increases when we increase the zwitterionic content of the copolymers.
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