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Several methods have been employed to install the different types of subsea equipment that are required for offshore oil and gas production systems. More recently, the increasing development of oil fields at remote, ultra-deepwater scenarios has been requiring heavier and more complex subsea equipment. In such scenarios the usual installation methods have been facing increasing challenges, including resonance effects associated to the dynamic behavior of the cable-equipment system. In this context, after presenting a review of the state-of-the-art of installation methods for subsea equipment, this work presents a methodology for the design and evaluation of an installation method based on the combination of steel wire and polyester ropes. The goal is to obtain a feasible and safe installation method that can avoid resonance effects along all phases of the lowering procedure, without the need of specialized devices such as heave compensators, and using only simpler installation vessels such as standard tugboats instead of more expensive and specialized vessels (such as drilling rigs). The method is evaluated by numerical simulations for case studies considering representative metocean data for Brazilian ultra-deepwater scenarios, following a methodology that considers the random characteristic of actual sea states by employing an irregular spectral representation. The results indicate that the method may indeed be feasible for the deepwater installation of heavier equipment, potentially being more cost-effective especially for remote locations where other more complex methods might become inefficient.

Citrus greening disease, also known as Huanglongbing (HLB), compromises the quality of citrus fruit and juice, causing increased bitterness, metallic taste, astringency and a burning mouthfeel. The chemical basis responsible for these changes remains largely unknown other than the roles of the bitter limonoids, limonin and nomilin, and of flavonoids that may cause astringency. A combination of chemical and sensory analyses was used to identify bitter components in HBL-affected orange juice (HLBOJ), and compared with juice from healthy fruit. DNA analysis of the juice revealed that HLBOJ was well infected with the bacteria, with Ct value of 27 compared with 33 for the healthy juice. There were differences (at least P

This paper presents an experimental and numerical study focused on the mode-I intralaminar toughness characterization of a woven carbon/epoxy composite loaded in compression and subjected to high strain rates. Simulations for non-standardized Single Edge Notch Bending (SENB) and Double Edge Notch (DEN) specimens were carried out using a continuum damage mechanics based failure model implemented as an user defined material model within ABAQUS software. A Finite Element Model was used in order to produce an optimal specimen for intralaminar fracture toughness tests. A new data reduction scheme based on the numerical evaluation of the strain energy release rate using the J-integral method is proposed to determine the stress intensity factor for composites. The proposed methodology accounts for finite geometry and material anisotropy effects. The dynamic tests were carried out at strain rates of 560 s - 1 , 690 s - 1 , 770 s - 1 using an adapted version of the Split Hopkinson Pressure Bar. A high-speed camera was used for monitoring the crack propagation. A Scanning Electron Microscope (SEM) was used to aid the fractographic analyses on the damaged surface of the tested samples searching for the possible failures mechanisms within the material. The experimental results indicated that the composite laminates studied herein are very sensitive to the strain rate effects.

Food waste disposal represents a major global source of predictable anthropogenic food subsidies and is exploited by many organisms. However, the energetic cost-benefits of foraging on these food subsidies have remained largely unexplored. Here we investigate the year-round foraging decisions of resident white storks, Ciconia ciconia, in Iberia, and assess the energetic and time cost-benefits of foraging on both landfill waste and natural food sources. To do so, we use GPS and acceleration data from 55 individuals tagged in southern Portugal between 2016 and 2019. We find that the probability of attending landfill sites was 60% during the non-breeding season and 44% during the breeding season. Moreover, foraging on landfill waste is a time- and energy-saving strategy; although birds had to travel 20% further to exploit this resource during the breeding period, they spent overall 10% less energy than when foraging on natural prey. We show that this relationship could be mediated by a reduction in foraging time and an increase in foraging efficiency while exploiting landfill waste. Surprisingly, we do not find any evidence that landfill specialists experienced any competitive advantage during landfill exploitation over birds that visit landfills occasionally. These insights are key to predict how species that rely on landfills can be affected by waste reduction initiatives planned by the European Union, and implement the necessary management strategies.

Air pollution is the single largest environmental risk today and is increasing in developing countries. In addition, exposure to air pollution is correlated to poor socioeconomic conditions owing to political processes and cultural and historic occupation of land. Ports have several structures that are potential emitters of pollutants such as large ship engines, diesel trucks, and trains. Owing to the considerable costs of implementing direct monitoring networks, alternatives like biomonitoring are an interesting approach to evaluate the environmental status of a particular area using living organisms or their parts such as bark, even though the use of bark as a biomonitor has several problems such as difficulties in determining the exposure period and its correlation with human exposure. Therefore, the use of a complementary mathematical logic is necessary. This study describes a methodological approach to evaluate the environmental risk from air pollution integrating data on environmental pollutants from tree bark using Fuzzy logic, based in the port city of Paranagua in the state of Parana in Brazil, and validated using income indicators. The results indicate that the risk distribution patterns have an inverse relationship with the income indicator, i.e., higher risk levels indicate lower income levels and vice versa. It was concluded that the system was able to identify the distribution of risk and that there is a context of environmental injustice in the region, where the environmental risk related to air pollution is inversely proportional to income levels. This type of information provides a decision making tool for environmental risk analysis from air pollution and can be used in the definition of public policies.

We studied the pathogenesis of Pseudocowpox virus (PCPV), a zoonotic parapoxvirus associated with mucocutaneous lesions in cattle. Inoculation of calves with PCPV isolate SD 76–65 intranasally (n = 6) or transdermally in the muzzle (n = 2) resulted in virus replication and shedding up to day 13 post-infection (pi). No local or systemic signs were observed in inoculated calves up to day 20pi, when the clinical monitoring was discontinued. However, from days 28–34 pi, seven (7/8) inoculated calves underwent an asynchronous clinical course characterized by development of a few (one or two) to countless papulo-pustular, erosive-fibrinous and scabby lesions in the muzzle, in some cases extending to the lips and gingiva. In some animals, the lesions coalesced, forming extensive fibrinotic/necrotic and scabby plaques covering almost entirely the muzzle. The clinical course lasted 8–15 days and spontaneously subsided after day 42pi. Infectious virus and/or viral DNA were detected in swabs collected from lesions of 5/8 animals between days 34 and 42pi. Histological examination of fragments collected from the muzzle lesions of two affected calves (day 36pi) revealed marked epidermal hyperplasia and severe orthokeratotic and parakeratotic hyperkeratosis, covered by thick scabs. The epidermis showed multifocal areas of keratinocyte coalescing necrosis and mild multifocal vacuolar degeneration. Sera of inoculated calves at 50pi showed partial virus neutralization at low dilutions, demonstrating seroconversion. The delayed and severe clinical course associated with virus persistence in lesions are novel findings and contribute for the understanding of PCPV pathogenesis.

This work presents a reduced integration method for the nonlinear coupled analysis of floating production systems, combining a “strong coupling” formulation with a variation of the Ritz-Wilson basis reduction technique. This leads to an uncoupled formulation for the reduced equations of motion, which may be solved analytically by the Duhamel integral expressing the convolution of the Green functions. These equations are implemented in a recursive time-domain step-by-step solution procedure where the convolution integrals are calculated numerically, with the range of the integration being simply the time step Δt. The method is tailored for the particular characteristics of the nonlinear dynamic behavior of FPS, including the selection of time steps between basis reevaluations: they are triggered according to the natural periods of the horizontal motions. The results from the case studies indicate that the goal of obtaining an efficient solution method has been reached, allowing an accurate evaluation of the response with lower computational costs.

This work presents the implementation, on computers with parallel architecture, of domain decomposition strategies for the coupled analysis of floating production systems (FPS). The strategies are associated to formulations for the coupling of the equations of motion of hull and lines, and to different algorithms for the solution of these equations. The strategies are grouped as “external” and “internal”. The former incorporates a “master-slave” scheme where the hull equations are solved in the “master” processor, and the equations of each line are solved in the “slave” processors. This scheme is associated to an external subcycling procedure, where the time step employed to integrate the hull equations is larger than the step for the lines. In the “internal” partition strategies, the FE mesh of each line is partitioned amongst the processors. Different strategies are presented, including an internal subcycling procedure associated to an explicit algorithm, using distinct time steps to integrate the equations of each partition (according to its physical characteristics); and an implicit domain decomposition method where completely arbitrary mesh partitions may be defined. Results of case studies are presented, to assess the performance of the parallel implementations described.

Considering the analysis of Floating Production Systems (FPS), this work describes two different formulations for the coupling of the hydrodynamic behavior of the hull and the hydrodynamic/structural behavior of the mooring lines and risers. These formulations are characterized by how the equations of motion of the hull and the lines are associated and solved. The first formulation is a “weak coupling” (WkC) scheme, focused on the equations of motion of the hull: the coupling is performed by forces acting on the right-hand side of the hull equations. The second formulation is a “strong coupling” (StC) scheme, where the Finite Element meshes of all mooring lines and risers are assembled together, and the hull is considered as a “node” of this model. Results of case studies employing the WkC and StC formulations are presented; based on these results, the behavior of these formulations is compared, in terms of their accuracy, computational performance, and applicability to different types of offshore systems. These results correspond to sequential implementations of the coupling formulations; further studies are presented in a subsequent paper, regarding different domain decomposition strategies associated to these coupled formulations, implemented on computers with parallel architecture.

On the French side of the Pyrenees, in the Bedous area of the Aspe Valley, fine-grained turbidites classically dated as Carboniferous and Triassic are attributed to the Upper Cretaceous. They contain fucoids and Globotruncanidae assemblages of the Dicarinella concavata Zone (Upper Turonian–Lower Santonian) and are metamorphosed at the contact of ophites intrusions. This discovery implies a new interpretation of the regional stratigraphy and palaeogeography. Moreover, it questions the age of the ophites emplacement in the region as well as the structural relationships between the ‘Bedous basin’ and the North Pyrenean Zone to the north and the Palaeozoic High Chain to the south. To cite this article: C. Desreumaux et al., C. R. Geoscience 334 (2002) 197–203.

Due to the perception of an implicit public guarantee, Banks too-big-to-fail may charge lower loan rates for the same risk in comparison to other groups of banks. However, empirically identifying such effect is challenging because size has many other advantages to banks besides the implicit guarantee. This paper makes use of the natural experiment represented by the discovery of new and large Brazilian oil reserves to conjecture an increase in the bailout perception of some Brazilian banks (the proposed too-rich- to-let-me-fail argument). It then investigates how the difference in loan pricing behavior across banks of different sizes has changed after the discovery. Results show that the difference of loan rates between medium and large banks decreases after the discovery. One possible explanation is that the conjectured increase in the bail-out perception affects mostly medium banks, which are at the margin to become too-big-to-fail, although other explanations are also feasible.