Cretaceous history of Pacific basin guyot reefs : a reappraisal based on geothermal endo-upwelling

The mid-cretaceous histories (origin, growth, death) of algal-rudist-stromatoporoid reef communities located on many Pacific basin guyots are complex and controversial. These shallow water, tropical communities originated on volcanic edifices extruded during the Barremian-Albian, grew upward during edifice subsidence/trangression throughout the Aptian, Albian and Cenomanian and several of them died almost synchronously near the Cenomanian-Turonian boundary. During their periods of origin and growth, we postulate that the reef ecosystem received dissolved oxygen by wave surge and nutrients by geothermal endo-upwelling. By this process oceanic waters of intermediate depth (approx. 500-1500m) were : (a) drown into the weathered and fractured volcanic summit and lower part of the older reef and driven upward through the porous framework bythe remnant geothermal gradient of the volcanic foundation and (b) emerged atthe reef surface to support the high metabolism of the living community. (D'après résumé d'auteur

Interpretation of the origin of massive replacive dolomite within atolls and submerged carbonate platforms : strontium isotopic signature ODP hole 866A, resolution Guyot, mid-Pacific mountains

Endo-upwelling is a geothermally driven convective process operating within the upper part of the volcanic foundation and overlying carbonate pile, in atolls and guyots. By this process deep oceanic water, rich in CO2, and dissolved nitrates, phosphates and silicates is drawn into the pile, circulates slowly upward through the porous-permeable carbonate interior and emerges at either the reef crest or lagoon on atolls to support the primary productivity of the surficial communities, or towards the interior of the platform surface on guyots. Continuous operation of the endo-upwelling process requires : (a) heat from the volcanic foundation; (b) an external impermeable apron on the submerged flanks to confine the convective flow within the pile; and (c) a porous cap from which water exiting the plumbing system returns to the ocean. (D'après résumé d'auteur

Geothermal endo-upwelling : a solution to the reef nutrient paradox ?

Les écosystèmes algo-coralliens sont paradoxaux du fait de leurs fortes biomasses et productivités au sein d'eaux océaniques oligotrophes. De plus, ils emportent dans l'océan (perte) une partie de leur biomasse ce qui implique un apport en nutriants neufs pour rétablir leur balance énergétique. Le fonctionnement par endo upwelling géothermique permet de résoudre ce paradoxe nutritif, en particulier au sein du gyre oligotrophe du Pacifique central (Polynésie). (Résumé d'auteur

Trophic relationships between palms and bruchids (Coleoptera : Bruchidae : Pachymerini) in Peruvian Amazonia

Des données quantitatives et qualitatives concernant les plantes hôtes des bruches des palmiers sont fournies pour une région de l'Amazonie où l'on disposait jusqu'à présent de peu d'informations. Ces données permettent d'étendre la distribution géographique et le spectre alimentaire de plusieurs espèces. Le rôle de la structure du fruit dans sa sensibilité à l'infestation par les bruches, le rôle de la maturité du fruit dans la sélection du site de ponte sont discutés. L'importance des conditions mésologiques, en particulier en zone inondable, dans la dynamique des populations de bruches, est relevée. Un parasitoïde spécialiste de #Caryoborus serripes, qui est un prédateur spécifique des noix d'#Astrocaryum, est obtenu pour la première fois; un trichogramme parasite des oeufs de cette même bruche est également identifié. (Résumé d'auteur

Measurement of residual stresses induced by sequential weld buttering and cladding operations involving a 2.25Cr-1Mo substrate material

Dissimilar metal welds are necessary in high-pressure subsea systems and in cases where forged components must be welded to pipelines. F22 (2.25Cr-1Mo) steel is often used in such forged steel components and, since this steel cannot enter service without undergoing post-weld heat treatment (PWHT), the components are usually prepared for field welds through the application of a buttering layer. Furthermore, a weld overlay is deposited for the purpose of mitigating corrosion. This combination of multiple welding tasks and dissimilar materials leads to the possibility of developing substantial residual stresses. This study aims to provide insights to the evolution of residual stresses at each stage of the welding operation. The assessment has been undertaken on laboratory-scale weld mock-ups using the contour method for residual stress measurement, and incremental centre hole drilling. It was found that both buttering and cladding introduce near-yield levels of tensile residual stresses, but that these stresses are successfully relieved upon PWHT

The Importance of Time Congruity in the Organisation.

In 1991 Kaufman, Lane, and Lindquist proposed that time congruity in terms of an individual's time preferences and the time use methods of an organisation would lead to satisfactory performance and enhancement of quality of work and general life. The research reported here presents a study which uses commensurate person and job measures of time personality in an organisational setting to assess the effects of time congruity on one aspect of work life, job-related affective well-being. Results show that time personality and time congruity were found to have direct effects on well-being and the influence of time congruity was found to be mediated through time personality, thus contributing to the person–job (P–J) fit literature which suggests that direct effects are often more important than indirect effects. The study also provides some practical examples of ways to address some of the previously cited methodological issues in P–J fit research

Prevalence of contagious bovine pleuropneumonia based on gross lesions in cattle at slaughter in Adamawa State, Nigeria

Contagious bovine pleuropneumonia is an important economic disease of cattle caused by Mycoplasma mycoides subspecies mycoides and manifested by anorexia, fever, dyspnoea, polypnoea, cough and nasal discharges. An eleven years (2006-2016) abattoir-based retrospective data were collated and analysed from Adamawa state Ministry of Livestock Production. Out of 241,700 cattle examined at post-mortem, 8,429 had CBPP-like lesions giving a prevalence of 3.49% (95% CI: 3.41-3.56). The overall prevalence for each local government area were 2.42% (95% CI: 2.35-2.49), 5.53% (95% CI: 5.30-5.74) and 8.97% (95% CI: 8.56-9.41) for Yola, Mubi and Ganye abattoirs respectively. There was significant association (p<0.05) between Local Government Areas and occurrence of CBPP. The annual highest prevalence of 5.75% (95% CI: 5.43-6.09) was recorded in 2010 with 1,128 cases and lowest prevalence of 2.43% (95% CI: 2.23-2.66) was recorded in 2007 with 505 cases. Based on season, highest prevalence rate of 3.85% (95% CI: 3.58-4.14) was recorded in February with 709 cases and lowest prevalence rate of 3.03% (95% CI: 2.80-3.28) was recorded in December with 605 cases. Both annual and monthly prevalence rates varied significantly (p<0.05). It was concluded that CBPP is endemic and widespread in Adamawa state. Hence, we recommend increased funding in the control of the disease, restriction of cattle movement and provision of cattle ranches.Keywords: Adamawa state, Cattle, Contagious bovine pleuropneumonia, Gross lesions, Prevalenc

Scenario-guided policy planning in Uganda

Using socio-economic scenarios in policy formulation allows for an anticipatory approach to governance processes and the formulation of policies/plans that take into account future uncertainty To fully benefit from the dividends of scenario planning in the Ugandan context, there is need to build the scenario-guided planning capacity of both public and private sectors. There is need for follow up and continuous engagement with government officials responsible after the review process to enable inclusion of recommendations generated into the final policy documents. In some cases, the abstract nature of national policy statements limits the level of detail, hence detailed scenario guided recommendations and information may not easily fit in the existing policy formats. The approach is new and requires extra awareness creation not only for the government officers who draft policies but also for other major policy actors such as the political leadership who approve the policies

Dosing of Convalescent Plasma and Hyperimmune Anti-SARS-CoV-2 Immunoglobulins:A Phase I/II Dose-Finding Study

Background and Objective: During the COVID-19 pandemic, trials on convalescent plasma (ConvP) were performed without preceding dose-finding studies. This study aimed to assess potential protective dosing regimens by constructing a population pharmacokinetic (popPK) model describing anti-SARS-CoV-2 antibody titers following the administration of ConvP or hyperimmune globulins (COVIg). Methods: Immunocompromised patients, testing negative for anti-SARS-CoV-2 spike antibodies despite vaccination, received a range of anti-SARS-CoV-2 antibodies in the form of COVIg or ConvP infusion. The popPK analysis was performed using NONMEM v7.4. Monte Carlo simulations were performed to assess potential COVIg and ConvP dosing regimens for prevention of COVID-19. Results: Forty-four patients were enrolled, and data from 42 were used for constructing the popPK model. A two-compartment elimination model with mixed residual error best described the Nab-titers after administration. Inter-individual variation was associated to CL (44.3%), V1 (27.3%), and V2 (29.2%). Lean body weight and type of treatment (ConvP/COVIg) were associated with V1 and V2, respectively. Median elimination half-life was 20 days (interquartile range: 17–25 days). Simulations demonstrated that even monthly infusions of 600 mL of the ConvP or COVIg used in this trial would not achieve potentially protective serum antibody titers for &gt; 90% of the time. However, as a result of hybrid immunity and/or repeated vaccination, plasma donors with extremely high antibody titers are now readily available, and a &gt; 90% target attainment should be possible. Conclusion: The results of this study may inform future intervention studies on the prophylactic and therapeutic use of antiviral antibodies in the form of ConvP or COVIg. Clinical trial registration number: NL9379 (The Netherlands Trial Register).</p