Redefining Walrus Stocks in Canada

Defining management units is basic to the sound management of resources. Walrus (Odobenus rosmarus rosmarus) are hunted throughout their range in Canada and are subject to other human activities requiring management decisions. Current management units are based on a comprehensive review and a stock assessment completed in the mid 1990s. Between 1993 and 2004, satellite-linked radio tags provided information on the movements of walrus in Canada’s High Arctic. These data were incorporated with other information that has become available since 1995 to reassess walrus management units in Canada. Tagging data and other information suggest that some finer discrimination of walrus populations is needed as a precautionary approach and to formulate testable hypotheses. Specifically, the previous North Water/Baffin Bay walrus stock may be considered to be three stocks: Baffin Bay, west Jones Sound, and Penny Strait Lancaster Sound stocks. The Foxe Basin population appears to comprise two stocks (North Foxe Basin and Central Foxe Basin) rather than one. Previously suspected subdivisions in the Hudson Bay-Davis Strait population are substantiated by isotopic evidence although sampling on a finer geographic scale is required before this stock can be partitioned. There is new evidence to support the previously postulated separation of the walrus in the Southern and Eastern Hudson Bay stock from all others, but no evidence to warrant subdivision.La définition des unités de gestion est fondamentale à la bonne gestion des ressources. Le morse (Odobenus rosmarus rosmarus) est chassé dans son aire d’extension au Canada, en plus d’être assujetti à d’autres activités humaines nécessitant des décisions en matière de gestion. Les unités de gestion actuelles sont fondées sur l’examen exhaustif et l’évaluation des groupes effectués vers le milieu des années 1990. Entre 1993 et 2004, des étiquettes radio par satellite ont fourni des renseignements sur les mouvements du morse dans le Grand Nord du Canada. Ces données ont été intégrées à d’autres informations disponibles depuis 1995 dans le but de réévaluer les unités de gestion du morse au Canada. Les données obtenues grâce aux étiquettes et d’autres informations laissent croire qu’il y a lieu d’avoir une discrimination plus raffinée des populations de morse en tant qu’approche de précaution et de formuler des hypothèses pouvant être mises à l’épreuve. Plus précisément, l’ancien groupe de morses des eaux du Nord et de la baie de Baffin peut être considéré comme trois groupes, soit les groupes de la baie de Baffin, du détroit Jones de l’ouest et des détroits de Penny et de Lancaster. Par ailleurs, la population du bassin Foxe semble comprendre deux groupes (le bassin Foxe du nord et le bassin Foxe du centre) au lieu d’un seul groupe. Les sous-divisions dont on se doutait auparavant pour ce qui est de la population de la baie d’Hudson et du détroit de Davis sont corroborées par des preuves isotopiques, quoiqu’un échantillonnage plus perfectionné s’avère nécessaire à l’échelle géographique avant que ce groupe ne puisse faire l’objet d’une répartition. Il y a de nouvelles preuves permettant de soutenir l’ancienne séparation hypothétique des groupes de morses dans le sud et l’est de la baie d’Hudson par rapport à tous les autres groupes, mais aucune preuve ne vient justifier une sous-division

The influence of straw residues on nutrient uptake and grain yield of wheat

Non-Peer Reviewe

Serologic Evidence of Brucella Spp. Exposure in Atlantic Walruses (Odobenus Rosmarus Rosmarus) and Ringed Seals (Phoca Hispida) of Arctic Canada

The first presumptive evidence of Brucella infection in marine mammals of Arctic Canada is reported. Blood samples were collected from 248 ringed seals (Phoca hispida) and 59 Atlantic walrus (Odobenus rosmarus rosmarus) from eight locations in the Canadian Arctic between 1987 and 1994. A competitive enzyme-linked immunosorbent assay (C-ELISA), using a specific monoclonal antibody to Brucella spp. cell wall components, was used to detect anti-Brucella spp. antibodies in the samples. Sera from ten seals and seven walruses exceeded the C-ELISA threshold that indicates that cattle have been exposed to Brucella spp. Five of the positive walrus sera were suitable for the tube agglutination test. All five were confirmed positive using this test. Although the bacterium has not yet been identified, it appears that a Brucella sp. or a Brucella-like bacterium may be enzootic in these species in the Canadian Arctic. It is also possible that the very low prevalence of antibodies in ringed seals and the seemingly random distribution of seropositive animals may indicate a sporadic infection from another enzootically infected phocid or predator (e.g., Arctic fox Alopex lagopus). Or perhaps, limited epizootics may have occurred in the areas where seropositive seals were found. A similar situation could also exist in the walrus of Foxe Basin. On rapporte la première preuve par inférence d'une infection des mammifères marins de l'Arctique canadien par le bacille Brucella. Entre 1987 et 1994, on a effectué des prélèvements sanguins sur 248 phoques annelés (Phoca hispida) et 59 morses de l'Atlantique (Odobenus rosmarus rosmarus) à huit endroits dans l'Arctique canadien. On a employé la technique immuno-enzymatique par compétition ÉLISA, en se servant d'un anticorps monoclonal spécifique aux composants de la paroi cellulaire de Brucella spp, afin de détecter les anticorps anti-Brucella sp dans les prélèvements. Les sérums de dix phoques et de sept morses dépassaient le seuil d'ÉLISA qui indique que la population animale a été exposée à Brucella spp. Cinq des sérums positifs de morses se prêtaient à l'épreuve d'agglutination en tube, et tous se sont révélés positifs. Bien qu'on n'ait pas encore identifié la bactérie, il semble que Brucella sp ou une bactérie semblable à Brucella puisse être enzootique à ces espèces dans l'Arctique canadien. Il est également possible que la faible fréquence globale d'anticorps chez le phoque annelé et la distribution apparemment erratique des animaux séropositifs soient l'indice d'une infection sporadique communiquée par un autre phocidé infecté par proximité dans le milieu ou encore par un prédateur (p. ex., le renard arctique Alopex lagopus). Ou bien des épizooties se seraient produites dans les régions où l'on a trouvé des phoques séropositifs. Une situation semblable pourrait aussi se retrouver chez le morse du bassin de Foxe

Maternal obesity is associated with the formation of small dense LDL and hypoadiponectinemia in the third trimester

Context: Maternal obesity is associated with high plasma triglyceride, poor vascular function, and an increased risk for pregnancy complications. In normal-weight pregnant women, higher triglyceride is associated with increased small, dense low-density lipoprotein (LDL). Hypothesis: In obese pregnancy, increased plasma triglyceride concentrations result in triglyceride enrichment of very low-density lipoprotein-1 particles and formation of small dense LDL via lipoprotein lipase. Design: Women (n = 55) of body mass index of 18–46 kg/m2 were sampled longitudinally at 12, 26, and 35 weeks' gestation and 4 months postnatally. Setting: Women were recruited at hospital antenatal appointments, and study visits were in a clinical research suite. Outcome Measures: Plasma concentrations of lipids, triglyceride-rich lipoproteins, lipoprotein lipase mass, estradiol, steroid hormone binding globulin, insulin, glucose, leptin, and adiponectin were determined. Results: Obese women commenced pregnancy with higher plasma triglyceride, reached the same maximum, and then returned to higher postnatal levels than normal-weight women. Estradiol response to pregnancy (trimester 1–3 incremental area under the curve) was positively associated with plasma triglyceride response (r2 adjusted 25%, P < .001). In the third trimester, the proportion of small, dense LDL was 2-fold higher in obese women than normal-weight women [mean (SD) 40.7 (18.8) vs 21.9 (10.9)%, P = .014], and 35% of obese, 14% of overweight, and none of the normal-weight women displayed an atherogenic LDL subfraction phenotype. The small, dense LDL mass response to pregnancy was inversely associated with adiponectin response (17%, P = .013). Conclusions: Maternal obesity is associated with an atherogenic LDL subfraction phenotype and may provide a mechanistic link to poor vascular function and adverse pregnancy outcome

Preeclampsia is associated with compromized maternal synthesis of long chain polyunsaturated fatty acids leading to offspring deficiency

Obesity and excessive lipolysis are implicated in preeclampsia (PE). Intrauterine growth restriction is associated with low maternal body mass index and decreased lipolysis. Our aim was to assess how maternal and offspring fatty acid metabolism is altered in mothers in the third trimester of pregnancy with PE (n=62) or intrauterine growth restriction (n=23) compared with healthy pregnancies (n=164). Markers of lipid metabolism and erythrocyte fatty acid concentrations were measured. Maternal adipose tissue fatty acid composition and mRNA expression of adipose tissue fatty acid–metabolizing enzymes and placental fatty acid transporters were compared. Mothers with PE had higher plasma triglyceride (21%, P<0.001) and nonesterified fatty acid (50%, P<0.001) concentrations than controls. Concentrations of major n−6 and n−3 long-chain polyunsaturated fatty acids in erythrocytes were 23% to 60% lower (all P<0.005) in PE and intrauterine growth restriction mothers and offspring compared with controls. Subcutaneous adipose tissue Δ−5 and Δ−6 desaturase and very long-chain fatty acid elongase mRNA expression was lower in PE than controls (respectively, mean [SD] control 3.38 [2.96] versus PE 1.83 [1.91], P=0.030; 3.33 [2.25] versus 1.03 [0.96], P<0.001; 0.40 [0.81] versus 0.00 [0.00], P=0.038 expression relative to control gene [square root]). Low maternal and fetal long-chain polyunsaturated fatty acid concentrations in PE may be the result of decreased maternal synthesis

Communication and trust in the bounded confidence model

The communication process in a situation of emergency is discussed within the Scheff theory of shame and pride. The communication involves messages from media and from other persons. Three strategies are considered: selfish (to contact friends), collective (to join other people) and passive (to do nothing). We show that the pure selfish strategy cannot be evolutionarily stable. The main result is that the community structure is statistically meaningful only if the interpersonal communication is weak.Comment: 6 pages, 5 figures, RevTeX, for ICCCI-201

Crystal structure and magnetic modulation in β−Ce2O2FeSe2

We report a combination of X-ray and neutron diffraction studies, Mossbauer spectroscopy and muon spin relaxation (muSR) measurements to probe the structure and magnetic properties of the semiconducting beta-Ce2O2FeSe2 oxychalcogenide. We report a new structural description in space group Pna21 which is consistent with diffraction data and second harmonic generation measurements and reveal an order-disorder transition on one Fe site at TOD ~ 330 K. Susceptibility measurements, Mossbauer and muSR reveal antiferromagnetic ordering below TN = 86 K and more complex short range order above this temperature. 12 K neutron diffraction data reveal a modulated magnetic structure with q = 0.444 bN*

The General Solution of Bianchi Type VIIhVII_h Vacuum Cosmology

The theory of symmetries of systems of coupled, ordinary differential equations (ODE) is used to develop a concise algorithm in order to obtain the entire space of solutions to vacuum Bianchi Einstein Field Equations (EFEs). The symmetries used are the well known automorphisms of the Lie algebra for the corresponding isometry group of each Bianchi Type, as well as the scaling and the time re-parametrization symmetry. The application of the method to Type VII_h results in (a) obtaining the general solution of Type VII_0 with the aid of the third Painlev\'{e} transcendental (b) obtaining the general solution of Type $VII_h$ with the aid of the sixth Painlev\'{e} transcendental (c) the recovery of all known solutions (six in total) without a prior assumption of any extra symmetry (d) The discovery of a new solution (the line element given in closed form) with a G_3 isometry group acting on T_3, i.e. on time-like hyper-surfaces, along with the emergence of the line element describing the flat vacuum Type VII_0 Bianchi Cosmology.Comment: latex2e source file, 27 pages, 2 tables, no fiure

Chitinozoan biostratigraphy of the regional Arenig Series in Wales and correlation with the global Lower–Middle Ordovician series and stages

The Arenig Fawr area of North Wales constitutes the type area for the British Lower to Middle Ordovician Arenig Series and is complemented by sections in the Carmarthen and Whitland areas of South Wales. We describe chitinozoan assemblages from both areas in order to aid correlation of the Arenig Series in its type region with the global Ordovician series and stages. Chitinozoans recorded from Arenig Fawr provide permissive rather than conclusive evidence but suggest that the Henllan Ash Member correlates with the upper Floian Stage Slice Fl3 or lower Dapingian Stage Slice Dp1. Better results were obtained from South Wales where six chitinozoan assemblages are distinguished, ranging in age from late Tremadocian to middle Darriwilian (early Llanvirn). Most species are known from South China, Gondwana and/or Baltica where there are controls on ranges. They show that much of the lower Arenig (Moridunian) succession in South Wales correlates with the upper Floian Stage (Fl3). Correlatives of the lower and middle Floian Stage (Fl1, Fl2), if present, must be represented by the Ogof Hên Formation and lowest Carmarthen Formation. Chitinozoan assemblages from the upper Arenig Series (Fennian Stage) are more readily correlated with Gondwanan biozones and indicate correlation of the Fennian Stage with the Dapingian and lower Darriwilian (Dw1) stages. The middle Arenig Whitlandian Stage is constrained in South Wales to an interval from the uppermost Floian Stage to the basal Dapingian Stage, resulting in an inferred increased rate of sediment accumulation

Modelling non-dust fluids in cosmology

Currently, most of the numerical simulations of structure formation use Newtonian gravity. When modelling pressureless dark matter, or `dust', this approach gives the correct results for scales much smaller than the cosmological horizon, but for scenarios in which the fluid has pressure this is no longer the case. In this article, we present the correspondence of perturbations in Newtonian and cosmological perturbation theory, showing exact mathematical equivalence for pressureless matter, and giving the relativistic corrections for matter with pressure. As an example, we study the case of scalar field dark matter which features non-zero pressure perturbations. We discuss some problems which may arise when evolving the perturbations in this model with Newtonian numerical simulations and with CMB Boltzmann codes.Comment: 5 pages; v2: typos corrected and refs added, submitted version; v3: version to appear in JCA