Population genetics of Ice Age brown bears

The Pleistocene was a dynamic period for Holarctic mammal species, complicated by episodes of glaciation, local extinctions, and intercontinental migration. The genetic consequences of these events are difficult to resolve from the study of present-day populations. To provide a direct view of population genetics in the late Pleistocene, we measured mitochondrial DNA sequence variation in seven permafrost-preserved brown bear (Ursus arctos) specimens, dated from 14,000 to 42,000 years ago. Approximately 36,000 years ago, the Beringian brown bear population had a higher genetic diversity than any extant North American population, but by 15,000 years ago genetic diversity appears similar to the modern day. The older, genetically diverse, Beringian population contained sequences from three clades now restricted to local regions within North America, indicating that current phylogeographic patterns may provide misleading data for evolutionary studies and conservation management. The late Pleistocene phylogeographic data also indicate possible colonization routes to areas south of the Cordilleran ice sheet.

Rabies in Experimentally Infected Bears, Ursus spp., with Epizootiologic Notes

Ten black bears, Ursus americanus Pallas, and three brown bears, U. arctos Linnaeus, were inoculated with rabies virus from naturally infected foxes in Alaska. The bears were more resistant than canine species, requiring at least 1,000 MLD50 of virus for infection. Low titres or negative results were obtained in salivary glands titrated in mice. Clinical course of the disease, post mortem findings, and microscopic lesions are described. Microscopic lesions were more· severe in brown bears, in which the inflammatory response was distinguished by the presence of numerous eosinophils in the perivascular infiltrate and among cells diffusely infiltrating the parenchyma. In both species, inclusion bodies were found only in the Purkinje cells of the cerebellum. Rabies is discounted as a factor in unprovoked attacks by bears on man at high latitudes. The epizootiology of rabies in a region where bears are numerous is discussed, with the conclusion that rabid foxes usually do not excrete sufficient quantities of virus in the saliva to infect bears. German title: Tollwut bei experimentell infizierten Bären, Ursus spp., mit epizootiologischen Anmerkungen German abtract: Zehn Schwarzbären, Ursus americanus Pallas, und drei Braunbären, U. arctos Linnaeus, wurden mit einem von Füchsen in Alaska isolierten Feldstamm des Tollwutvirus infiziert. Die Untersuchungsergebnisse lassen erkennen, daß Bären eine größere Resistenz gegenüber Tollwutinfektion aufweisen als hundeartige Karnivoren, und zwar konnten sie nicht mit weniger als 1000 MLD50 des Tollwutvirus infiziert werden. Das Virus war selten nachweisbar in den Speicheldrüsen der tollwuterkrankten Bären. Klinik und Pathologie der Tollwut bei Bären wurden kurz beschrieben. Die im Gehirn vorkommenden entzündlichen Veränderungen waren bei Braunbären besonders schwer und unterschieden sich durch die Häufigkeit der eosinophilen Leukozyten in den perivasculären und Gewebs-Infiltraten. Bei beiden Arten wurden Einschlußkörperchen nur in den Purkinje-Zellen beobachtet. Die Epizootiologie der Tollwut auf der Alaska-Halbinsel, wo Bären häufig vorkommen, wurde besprochen. Die Ergebnisse deuten an, daß Füchse wenig Virus mit dem Speichel ausscheiden, und selten soviel, daß es für die Infektion von Bären ausreicht. French title: La rage expérimentale chez les ours, Ursus spp., avec observations épizootiologiques French abstract: Dix ours noirs, Ursus americanus Pallas, et trois ours bruns, U. arctos Linnaeus, ont été inoculés avec de virus rabique provenant des renards infectés naturellement dans l'Alaska. Les ours Ont été plus résistants au virus que des espèces canines, et pour produire l'infection chez les ours, au moins 1000 MLD50 ont été requis. La titration des glandes salivaires chez des souris a données des titres peu éléves ou des résultats négatifs. La course clinique de la maladie, les observations des autopsies, et les lésions microscopiques sont decrites. Les lésions microscopiques les plus sévères ont été observées chez les ours bruns, dans lesquels la réponse inflammatoire a été distinguée par la présence de nombreux éosinophiles dans l'infiltration périvasculaire et parmi les cellules infiltrées diffusément dans Ie parenchyme. Chez les deux espèces des ours, des corps d'inclusion ont été trouvés seulement dans les cellules de Purkinje du cervelet. On a discuté l'épizootiologie de la rage dans une région où des ours sont nombreux, avec la conclusion qu'il y a dans la salive des renards rabiques une quantité de virus insuffisante pour infecter les ours. é ó í á ú Spanish title: Rabia en osos, Ursus spp., infectados experimentalmente, con anotaciones epizootológicas Spanish abstract: Diez osos negros, Ursus americanus Pallas, y tres osos pardos, U. arctos Linea, se infectaron con una estirpe campal de virus rábico aislada de zorros en Alasca. Los resultados de la experiencia permiten reconocer que los osos presentan una resistencia mayor frente a la infección rábica que los carnívoros cánidos, pues no se pudieron infectar con menos de 1.000 DML50 de virus rábico. El virus era muy raras veces identificable en las glándulas salivales de los osos enfermos de rabia. Se describen sucintamente la clínica y patología de la rabia en los osos. Las modificaciones inflamatorias en el cerebro eran muy graves en el oso pardo y se distinguían por la frecuencia de los leucocitos eosinófilos en los infiltrados perivasculares e hísticos. En ambas especies solo se hallaron corpúsculos de inclusión en las células de Purkinje. Se discute la epizootología de la rabia en la península de Alasca, donde es frecuente Ia presencia de osos. Los resultados señalan que los zorros eliminan poco virus con la saliva y casi nunca en cantidad tal que fuese suficiente para infectar los osos.

Reindeer habitat selection under the risk of brown bear predation during calving season

The depredation of semi-domesticated reindeer by large carnivores reflects an important human-wildlife conflict in Fennoscandia. Recent studies have revealed that brown bears (Ursus arctos) may kill substantial numbers of reindeer calves (Rangifer tarandus tarandus) in forest areas in Sweden. Several authors have suggested that predation risk is an important driver of habitat selection in wild Rangifer populations where predation is a limiting factor, but little is known about these mechanisms in semi-domesticated populations. We examined the habitat selection of female reindeer in relation to spatial and temporal variations in brown bear predation risk on the reindeer calving grounds and evaluated the simultaneous responses of brown bears and reindeer to landscape characteristics. We used GPS data from 110 reindeer years (97 individuals) and 29 brown bear years (19 individuals), from two reindeer herding districts in the forest area of northern Sweden. Our results did not indicate that reindeer alter their behavior in response to spatiotemporal variation in brown bear predation risk, on the scale of the calving range. Instead, we suggest that spatiotemporal behavioral adjustments by brown bears were the main driver of prey-predator interactions in our study system. Contrasting responses by brown bears and reindeer to clear-cuts and young forest indicate that forestry can influence species interactions and possibly yield negative consequences for the reindeer herd. Even if clear-cuts may be beneficial in terms of calf survival, logging activity will eventually cause greater abundance of young regenerating forest, reducing available reindeer habitats and increasing habitat preferred by brown bears. Domestication may have made semi-domesticated reindeer in Fennoscandia less adapted to cope with predators. Areal restrictions, limiting the opportunity for dispersion and escape, possibly make the calves more susceptible to predation. Also, a generally higher population density in semi-domesticated herds compared to wild populations can make dispersion a less efficient strategy and the reindeer calves easier prey. Overall, the lack of ability of the reindeer females to reduce brown bear encounter risk on the scale of the calving range is probably an important reason for the high brown bear predation rates on reindeer calves documented in our study areas. 

Recovery of large carnivores in Europe's modern human-dominated landscapes.

The conservation of large carnivores is a formidable challenge for biodiversity conservation. Using a data set on the past and current status of brown bears (Ursus arctos), Eurasian lynx (Lynx lynx), gray wolves (Canis lupus), and wolverines (Gulo gulo) in European countries, we show that roughly one-third of mainland Europe hosts at least one large carnivore species, with stable or increasing abundance in most cases in 21st-century records. The reasons for this overall conservation success include protective legislation, supportive public opinion, and a variety of practices making coexistence between large carnivores and people possible. The European situation reveals that large carnivores and people can share the same landscape.

Genetic assignment methods for the direct, real-time estimation of migration rate: a simulation-based exploration of accuracy and power

Genetic assignment methods use genotype likelihoods to draw inference about where individuals were or were not born, potentially allowing direct, real-time estimates of dispersal. We used simulated data sets to test the power and accuracy of Monte Carlo resampling methods in generating statistical thresholds for identifying F-0 immigrants in populations with ongoing gene flow, and hence for providing direct, real-time estimates of migration rates. The identification of accurate critical values required that resampling methods preserved the linkage disequilibrium deriving from recent generations of immigrants and reflected the sampling variance present in the data set being analysed. A novel Monte Carlo resampling method taking into account these aspects was proposed and its efficiency was evaluated. Power and error were relatively insensitive to the frequency assumed for missing alleles. Power to identify F-0 immigrants was improved by using large sample size (up to about 50 individuals) and by sampling all populations from which migrants may have originated. A combination of plotting genotype likelihoods and calculating mean genotype likelihood ratios (D-LR) appeared to be an effective way to predict whether F-0 immigrants could be identified for a particular pair of populations using a given set of markers.

Geographic variation among brown and grizzly bears (Ursus arctos) in North America / by E. Raymond Hall.

no.13 (1984)

A plan for the management of brown bear in relation to other resources on Admiralty Island, Alaska /

Caption title.

Reproducing violence: Rihanna, Chris Brown and the aestheticisation of the Ciudad Juarez Femicides.

When Kate and Laura Mulleavy of Rodarte worked with MAC to create their Autumn/Winter 2010 makeup collection and based their ideas on the murdered women of Ciudad Juarez, there was a public and industry outcry which led to the withdrawal of cosmetics with names such as ‘Factory’ ‘Juarez’ and ‘Ghost Town’. Rodarte tapped into the borderland mythologies of Juarez and crated an illusory fantasy world which sought to simultaneously obliterate and venerate the dead women. One eyeshadow, ‘Bordertown’, appears to look like chunks of rotting flesh streaked with blood. The models for their catwalk show had hollow blackened eyes, green-white pallor and lips that had been bloodlessly ‘lip-erased’ with a product specifically designed for the purpose. In Spanish, maquillar is to make up, to assemble. The women in the factories are asked to repeat simple mechanical operations thousands of times a day to make up the products which will be sold by global corporations. At the same time their images are being assembled, made up and aestheticized to create a cosmetic erasure of the crimes which they are subject to. When two American women and a global company make profit from this dangerous cosmetic erasure in order to sell products, the borders between bodies, countries, art and crime become leaky through the act and the illusion of symbiosis between the women of Ciudad Juarez and the products they inspired is threatened by the haunting of exploitation. Since then, the situation has become more complex. Chris Brown got a neck tattoo, based, he says, on the promotional material produced by MAC for the Rodarte sisters campaign. The image, which is of a skull, bears a striking resemblance to the police photographs of his ex, and now current, girlfriend, superstar Rihanna. The controversy over gendered violence, race and exploitation, begun by Rodarte and MAC, came back, haunting, once again. This paper seeks to address these connections, and ask what happens when domestic violence collides with globalism, fashion and murder.

Lysine and zinc chelate in diets for brown laying hens: effects on egg production and composition

It was evaluated the effects of levels of digestible lysine and chelate zinc combined in the diet for laying on the egg quality. It was used 720 birds, from 48 to 60 weeks of age, distributed in a completely randomized design in a 3 × 5 factorial scheme with three levels of zinc and five levels of lysine, applied into six replicates in the experimental units of eight birds per plot. The levels were: 137, 309 and 655 ppm zinc and 0.482, 0.527, 0.582, 0.644 and 0.732% digestible lysine. It was not observed any interaction among digestible lysine and zinc for the primary variables of fractions and egg composition. Levels of zinc reduced egg weight, suggesting the lowest efficiency in nutrient intake. At the highest dietary concentration of zinc, the addition of digestible lysine coincided with a linear increase in shell weight. However, zinc addition, regardless of lysine level in the diet, resulted in the reduction of egg weight and of the percentage of mineral matter in the yolk, limiting the efficiency of mineral deposition in this fraction of the egg. Concentration of zinc that produced the best results was 137 ppm inasmuch as higher quantities limit the use of digestible lysine, with effects harming composition and egg quality. The study indicates the following requirement for digestible lysine: 0.639% from the 48th to the 52nd week, 0.679% from the 52nd to 56th week, and 0.635% from the 56th to the 60th week. Considering the total period from 48th to the 60th week, the level 0.638% of lysine or the daily intake of 707 mg of the amino acid met the requirement for egg quality of semi-heavy layers used in this study.

An insight into the sialotranscriptome of the brown dog tick, Rhipicephalus sanguineus

Background: Rhipicephalus sanguineus, known as the brown dog tick, is a common ectoparasite of domestic dogs and can be found worldwide. R. sanguineus is recognized as the primary vector of the etiological agent of canine monocytic ehrlichiosis and canine babesiosis. Here we present the first description of a R. sanguineus salivary gland transcriptome by the production and analysis of 2,034 expressed sequence tags (EST) from two cDNA libraries, one consctructed using mRNA from dissected salivary glands from female ticks fed for 3-5 days (early to mid library, RsSGL1) and the another from ticks fed for 5 days (mid library, RsSGL2), identifying 1,024 clusters of related sequences. Results: Based on sequence similarities to nine different databases, we identified transcripts of genes that were further categorized according to function. The category of putative housekeeping genes contained similar to 56% of the sequences and had on average 2.49 ESTs per cluster, the secreted protein category contained 26.6% of the ESTs and had 2.47 EST's/clusters, while 15.3% of the ESTs, mostly singletons, were not classifiable, and were annotated as ""unknown function"". The secreted category included genes that coded for lipocalins, proteases inhibitors, disintegrins, metalloproteases, immunomodulatory and antiinflammatory proteins, as Evasins and Da-p36, as well as basic-tail and 18.3 kDa proteins, cement proteins, mucins, defensins and antimicrobial peptides. Comparison of the abundance of ESTs from similar contigs of the two salivary gland cDNA libraries allowed the identification of differentially expressed genes, such as genes coding for Evasins and a thrombin inhibitor, which were over expressed in the RsSGL1 (early to mid library) versus RsSGL2 (mid library), indicating their role in inhibition of inflammation at the tick feeding site from the very beginning of the blood meal. Conversely, sequences related to cement (64P), which function has been correlated with tick attachment, was largely expressed in the mid library. Conclusions: Our survey provided an insight into the R. sanguineus sialotranscriptome, which can assist the discovery of new targets for anti-tick vaccines, as well as help to identify pharmacologically active proteins.

SSSPM J1102-3431 brown dwarf characterization from accurate proper motion and trigonometric parallax

Context. In 2005, Scholz and collaborators discovered, in a proper motion survey, a young brown dwarf SSSPM J1102-3431 (SSSPM J1102) of spectral type M8.5, probable member of the TW Hydrae Association and possible companion of the T Tauri star TWHya. The physical characterization of SSSPM J1102 was based on the hypothesis that it forms a binary system with TWHya. The recent discovery of a probable giant planet with a very short-period inside the TW Hya protoplanetary disk, as well as a disk around SSSPM J1102, make it especially interesting and important to measure well the physical parameters of SSSPM J1102. Aims. Trigonometric parallax and proper motion measurements of SSSPM J1102 are necessary to test for TWA membership and, thus, to determine the mass and age of this young brown dwarf and the possibility that it forms a wide binary system with TW Hya. Methods. Two years of regular observations at the ESO NTT/SUSI2 telescope have enabled us to determine the trigonometric parallax and proper motion of SSSPM J1102. Results. With our accurate distance determination of 55.2(-1.4)(+1.6) pc and proper motions of (-67.2, -14.0) +/- 0.6 mas/yr, we could confirm SSSPM J1102 as a very probable member of TWA. Assuming the TW Hydrae association age of 5-10 Myr, the evolutionary models compared to the photometry of this young brown dwarf indicate a mass of M = 25 +/- 5 M(Jup) and an effective temperature T(eff) = 2550 +/- 100 K. Conclusions. Our parallax and proper motion determination allow us to precisely describe the physical properties of this low mass object and to confirm its TWA membership. Our results indicate that SSSPMJ1102 may be a very wide separation companion of the star TW Hya.

Transiting exoplanets from the CoRoT space mission XV. CoRoT-15b: a brown-dwarf transiting companion

We report the discovery by the CoRoT space mission of a transiting brown dwarf orbiting a F7V star with an orbital period of 3.06 days. CoRoT-15b has a radius of 1.12(-0.15)(+0.30) R(Jup) and a mass of 63.3 +/- 4.1 M(Jup), and is thus the second transiting companion lying in the theoretical mass domain of brown dwarfs. CoRoT-15b is either very young or inflated compared to standard evolution models, a situation similar to that of M-dwarf stars orbiting close to solar-type stars. Spectroscopic constraints and an analysis of the lightcurve imply a spin period in the range 2.9-3.1 days for the central star, which is compatible with a double-synchronisation of the system.

Effect of pH and oxalic acid on the reduction of Fe(3+) by a biomimetic chelator and on Fe(3+) desorption/adsorption onto wood: Implications for brown-rot decay

Fenton reaction is thought to play an important role in wood degradation by brown-rot fungi. In this context, the effect of oxalic acid and pH on iron reduction by a biomimetic fungal chelator and on the adsorption/desorption of iron to/from wood was investigated. The results presented in this work indicate that at pH 2.0 and 4.5 and in the presence of oxalic acid, the phenolate chelator 2,3-dihydroxybenzoic acid (2,3-DHBA) is capable of reducing ferric iron only when the iron is complexed with oxalate to form Fe mono-oxalate (Fe(C(2)O(4))(+)). Within the pH range tested in this work, this complex formation occurs when the oxalate:Fe(3+) molar ratio is less than 20 (pH 2.0) or less than 10 (pH 4.5). When aqueous ferric iron was passed through a column packed with milled red spruce (Picea rubens) wood equilibrated at pH 2.0 and 4.5. it was observed that ferric iron binds to wood at pH 4.5 but not at pH 2.0, and the bound iron could then be released by application of oxalic acid at pH 4.5. The release of bound iron was dependent on the amount of oxalic acid applied in the column. When the amount of oxalate was at least 20-fold greater than the amount of iron bound to the wood, all bound iron was released. When Fe-oxalate complexes were applied to the milled wood column equilibrated in the pH range of 2-4.5, iron from Fe-oxalate complexes was bound to the wood only when the pH was 3.6 or higher and the oxalate:Fe(3+) molar ratio was less than 10. When 2,3-DHBA was evaluated for its ability to release iron bound to the milled wood, it was found that 2,3-DHBA possessed a greater affinity for ferric iron than the wood as 2,3-DHBA was capable of releasing the ferric iron bound to the wood in the pH range 3.6-5.5. These results further the understanding of the mechanisms employed by brown-rot fungi in wood biodegradation processes. (C) 2009 Elsevier Ltd. All rights reserved.

Peach brown rot incidence related to pathogen infection at different stages of fruit development in an organic peach production system

Brown rot, caused by Monilinia fructicola, is the most widespread disease for organic peach production systems in Brazil. The objective of this study was to determine the favorable periods for latent infection by M. fructicola in organic systems. The field experiment was carried out during 2006, 2007 and 2008 using the cultivar Aurora. After thinning fruits were bagged using white paraffin bags, and the treatments were performed by removing the bags and exposing the fruit for four days to the natural infection during each of seven fruit stages from pit hardening to harvest. Throughout the entire growing season, the conidial density and the weather variables were measured and related to the disease incidence using multiple regression analyses. At the fourth day after harvest in each season, the cumulative disease incidence was assessed, and it ranged from 40 to 98%. The incidence of brown rot on fruit that were exposed during the embryo growing stage was lower than that of unbagged fruit throughout the entire season in 2006 and 2008. The relative humidity and the conidia density were significantly correlated to disease incidence. Based on our results, M. fructicola can infect peaches during any stage of fruit development, and control of the disease must be revised to account for organic peach production systems. (C) 2011 Elsevier Ltd. All rights reserved.

Characterization of Brazilian lager and brown ale beers based on color, phenolic compounds, and antioxidant activity using chemometrics

BACKGROUND: Epidemiological studies have shown that beer has positive effects on inhibiting atherosclerosis, decreasing the content of serum low-density lipoprotein cholesterol and triglycerides, by acting as in vivo free radical scavenger. In this research, the antioxidant activity of commercial Brazilian beers (n = 29) was determined by the oxygen radical absorbance capacity (ORAC) and 1,1 -diphenyl-2-picrylhydrazyl (DPPH(center dot)) assays and results were analyzed by chemometrics. RESULTS: The brown ale samples (n = 11) presented higher (P < 0.05) flavonoids (124.01 mg L(-1)), total phenolics (362.22 mg L(-1)), non-flavonoid phenolics (238.21 mg L(-1)), lightness (69.48), redness (35.75), yellowness (55.71), color intensity (66.86), hue angle (59.14), color saturation (0.9620), DPPH(center dot) values (30.96% inhibition), and ORAC values (3,659.36 mu mol Trolox equivalents L(-1)), compared to lager samples (n = 18). Brown ale beers presented higher antioxidant properties (P < 0.05) measured by ORAC (1.93 times higher) and DPPH (1.65 times higher) compared to lager beer. ORAC values correlated well with the content of flavonoids (r = 0.47; P = 0.01), total phenolic compounds (r = 0.44; P < 0.01) and DPPH (r = 0.67; P < 0.01). DPPH values also correlated well to the content of flavonoids (r = 0.69; P < 0.01), total phenolic compounds (r = 0.60; P < 0.01), and non-flavonoid compounds (r = 0.46; P = 0.01). CONCLUSION: The results suggest that brown ale beers, and less significantly lager beers, could be sources of bioactive compounds with suitable free radical scavenging properties. (C) 2010 Society of Chemical Industry