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The development of new drugs for idiopathic pulmonary fibrosis strongly relies on preclinical experimentation, which requires the continuous improvement of animal models and integration with in vivo imaging data. Here, we investigated the lung distribution of bleomycin (BLM) associated with the indocyanine green (ICG) dye by fluorescence imaging. A long-lasting lung retention (up to 21 days) was observed upon oropharyngeal aspiration (OA) of either ICG or BLM + ICG, with significantly more severe pulmonary fibrosis, accompanied by the progressive appearance of emphysema-like features, uniquely associated with the latter combination. More severe and persistent lung fibrosis, together with a progressive air space enlargement uniquely associated with the BLM + ICG group, was confirmed by longitudinal micro-computed tomography (CT) and histological analyses. Multiple inflammation and fibrosis biomarkers were found to be increased in the bronchoalveolar lavage fluid of BLM- and BLM + ICG-treated animals, but with a clear trend toward a much stronger increase in the latter group. Similarly, in vitro assays performed on macrophage and epithelial cell lines revealed a significantly more marked cytotoxicity in the case of BLM + ICG-treated mice. Also unique to this group was the synergistic upregulation of apoptotic markers both in lung sections and cell lines. Although the exact mechanism underlying the more intense lung fibrosis phenotype with emphysema-like features induced by BLM + ICG remains to be elucidated, we believe that this combination treatment, whose overall effects more closely resemble the human disease, represents a valuable alternative model for studying fibrosis development and for the identification of new antifibrotic compounds.

One of the proven technologies for reservoir monitoring is 4D (time-lapse) seismic. It allows tracking the fluid front for water & gas and detecting pressure & density changes. Although 4D seismic monitoring is challenging in the Middle Eastern carbonate reservoirs, dealing with non-repeated acquisition geometries pose additional challenges. This paper will present how the 4D seismic processing methods and techniques were applied to overcome the following challenges from an offshore Jurassic carbonate oil and gas field: Seismic acquisition geometry differences between the two surveys leading to strong 4D noise related to repeatability issuesMultiple contamination especially in shallow water environment (water depth ranges from 15 to 25m) Cascaded application of denoise and demultiple procedures were performed. Different types of migration were conducted too. In order to overcome specifically acquisition geometry differences between legacy and monitor surveys, Least-Squares Migration algorithm was applied to 4D datasets. 4D Least-Squares migration showed better 4D inversion results compared with the ones from Kirchhoff migration. As 4D inversion signal has the same order of magnitude as 4D noise, additional information such as geology and well production data were required to discriminate 4D signal from noise. Nevertheless, some areas still suffer from residual multiples that generate strong and low frequency noise in 4D inversion results. However, many 4D seismic anomalies were validated as 4D signal mainly corresponding to 4D P-impedance increase which were nicely matched with water cut observed at wells and with water saturation from reservoir simulation. As a general observation, the water rise observed in 4D seismic inversion results was higher (shallower) than dynamic model water rise. In addition, 4D water rise showed heterogeneous water paths compared to the uniform one in the dynamic model. 4D interpretation results were integrated in the reservoir model.

Systemic sclerosis (SSc) is an autoimmune disease characterized by an excessive production and accumulation of collagen in the skin and internal organs often associated with interstitial lung disease (ILD). Its pathogenetic mechanisms are unknown and the lack of animal models mimicking the features of the human disease is creating a gap between the selection of anti-fibrotic drug candidates and effective therapies. In this work, we intended to pharmacologically validate a SSc-ILD model based on 1 week infusion of bleomycin (BLM) by osmotic minipumps in C57/BL6 mice, since it will serve as a tool for secondary drug screening. Nintedanib (NINT) has been used as a reference compound to investigate antifibrotic activity either for lung or skin fibrosis. Longitudinal Micro-CT analysis highlighted a significant slowdown in lung fibrosis progression after NINT treatment, which was confirmed by histology. However, no significant effect was observed on lung hydroxyproline content, inflammatory infiltrate and skin lipoatrophy. The modest pharmacological effect reported here could reflect the clinical outcome, highlighting the reliability of this model to better profile potential clinical drug candidates. The integrative approach presented herein, which combines longitudinal assessments with endpoint analyses, could be harnessed in drug discovery to generate more reliable, reproducible and robust readouts.

Background.Idiopathic Pulmonary Fibrosis is a progressive disease with short life expectancy and no disease-modifying pharmacological therapy. The continuous refinement of animal models and the integration of in-vivo imaging techniques is fundamental for the selection of new antifibrotic drugs.Indocyanine Green (ICG), a fluorescent dye, was administered by oropharyngeal aspiration (OA) to mice with Bleomycin (BLM) to map the lung exposure.Methods.Female mice C57bl/6 were treated via OA with BLM+ICG or ICG. Animals were imaged at 7, 14 and 21 days either with the fluorescent system or Micro-CT. At each time point subsets of mice were sampled for ex-vivo assessment. Histological assessment of fibrosis by Ashcroft score, airspace enlargements and mean linear intercept (MLI) were evaluated at 7, 14 and 21 days. Leukocytes and cytokines were measured in bronchoalveolar lavage fluid. Results.Fluorescence imaging revealed a persistent lung signal in both groups until 21 days. In BLM+ICG group, Micro-CT detected a marked increase in hypo- and non-aerated tissues throughout the study. At later time points hyper-inflated tissue was detected. Histology revealed high Ashcroft score throughout the time-course with a prominent increase in airspace size and MLI at day 21. ICG mice had healthy lungs.Conclusions.We showed that ICG can be used as a tracer to map the distribution of BLM in lungs. However, BLM+ICG produced unexpected severe lung changes different from pure BLM model, such as emphysema-like features which progressively worsened. The multimodalities approach warranted characterization of the distinctive features of this new pulmonary fibrosis model and provided fundamentals for in-vivo translation.

Eph receptors, comprising A and B classes, interact with cell-bound ephrins generating bidirectional signaling. Although mainly related to carcinogenesis and organogenesis, the role of Eph/ephrin system in inflammation is growingly acknowledged. Recently, we showed that EphA/ephrin-A proteins can modulate the acute inflammatory responses induced by mesenteric ischemia/reperfusion, while beneficial effects were granted by EphB4, acting as EphB/ephrin-B antagonist, in a murine model of Crohn’s disease (CD). Accordingly, we now aim to evaluate the effects of UniPR1331, a pan-Eph/ephrin antagonist, in TNBS-induced colitis and to ascertain whether UniPR1331 effects can be attributed to A- or B-type signaling interference. The potential anti-inflammatory action of UniPR1331 was compared to those of the recombinant proteins EphA2, a purported EphA/ephrin-A antagonist, and of ephrin-A1-Fc and EphA2-Fc, supposedly activating forward and reverse EphA/ephrin-A signaling, in murine TNBS-induced colitis and in stimulated cultured mononuclear splenocytes. UniPR1331 antagonized the inflammatory responses both in vivo, mimicking EphB4 protection, and in vitro, EphA/ephrin-A proteins were inactive or only weakly effective. Our findings represent a further proof-of-concept that blockade of EphB/ephrin-B signaling is a promising pharmacological strategy for CD management and highlight UniPR1331 as a novel drug candidate, seemingly working through the modulation of immune responses.

Systemic sclerosis (SSc) is an autoimmune disease characterized by an excessive production and accumulation of collagen in the skin and internal organs often associated with interstitial lung disease (ILD). The unknown pathogenetic mechanisms of SSc-ILD and the lack of animal models mimicking the features of the human disease contribute to create a gap between the selection of antifibrotic drug candidates and effective therapies. Nintedanib (NINT) was used as a tool compound to validate the pharmacological response either on lung or skin fibrosis in a SSc-ILD mouse model. The model is based on the continuous infusion of bleomycin (BLM) by osmotic minipumps for 1 week in the C57BL/6 female mice. Longitudinal Micro-CT analysis highlighted a significant slowdown in lung fibrosis progression after NINT treatment, then confirmed by histology. However, no significant effect was observed on lung hydroxyproline content, inflammatory infiltrate and skin lipoatrophy. The modest pharmacological effect reported reflects the clinical outcome, lighting up the reliability of this model to serve as secondary screening to profile the best clinical drug candidates. Moreover, we have underlined the pivotal role of Micro-CT imaging, together describing the relevant readouts and the importance of their validation prior to use for drug discovery.

Background: Despite the development of modern veterinary medicine, rural populations in developing countries continue to treat their animals with medicinal plants due to a combination of their low cost, easy availability, perceived efficacy and the absence of veterinary clinics. So, this study aimed to assess the consensus on the ethnobotanical knowledge from small-holders and to assess their preference either on medicinal plants or synthetic pharmaceuticals. Methods: Interviews were conducted between January and March 2015 with 30 people of both sexes, aged 24-96 years in Dom Helder Câmara, the largest rural settlement arisen by land reform efforts with remaining Caatinga vegetation in the state of Alagoas, northeast Brazil. The following indices were calculated to help interpret the data: Smith's Salience Index, Informant Consensus Factor (ICF) and Fidelity Level (FL). Results: Fifty-four species of plants in 45 genera and 25 botanical families were reported as treatments for 33 veterinary diseases. The highest salience value was found for Aloe vera (0.361) and Guapira graciliflora (0.336). The highest ICF values were recorded for the categories Ecto and endoparasite (0.670) and Gastrointestinal (0.630). In 76.5% of cases only the plant was used and in 23.5% of the cases synthetic pharmaceuticals were also considered as a treatment option. The highest FL values were found for G. graciliflora (84.62%) and Citrus limon (75.00%). Conclusions: Our results suggest that medicinal plants are an important alternative to synthetic remedies in this area, especially for treating helminthiasis, which cause great damage in the production of meat and derivatives. FL results may serve as the basis for prioritization of species for pharmacological studies. Key words: ethnoveterinary medicine, herbal medicine, livestock, phytotherapy, traditional knowledge.

Adoption of new technologies is a key enabler towards retaining competitiveness, taking full advantage of market opportunities to achieve ADNOC's 2030 smart growth strategy. TechRoad is an innovative in-house built solution that fully automates and streamlines the technology-adoption business process from technology registration to evaluation, piloting and deployment. Originally developed by ADNOC Onshore as an advanced technology management system and a decision making tool to generate the required technology roadmaps for our business challenges, ADNOC Management has recognized TechRoad as a progressive tool for incorporation across ADNOC's value chain. Launched in late 2018, and acclaimed by technology providers, TechRoad's registration portal was the first step taken towards ADNOC corporate integration.

Besides their long-known critical role in embryonic growth and in cancer development and progression, erythropoietin-producing hepatocellular carcinoma type B (EphB) receptor tyrosine kinases and their ephrin-B ligands are involved in the modulation of immune responses and in remodeling and maintaining the integrity of the intestinal epithelial layer. These processes are critically involved in the pathogenesis of inflammatory-based disorders of the gut, like inflammatory bowel diseases (IBDs). Accordingly, our aim was to investigate the role of the EphB/ephrin-B system in intestinal inflammation by assessing the local and systemic effects produced by its pharmacological manipulation in 2,4,6-trinitrobenzenesulfonic acid (TNBS)- (Th1-dependent model) and dextran sulphate sodium (DSS)- (innate response model) induced colitis in mice. To this purpose, we administered chimeric Fc-conjugated proteins, allegedly able to uni-directionally activate either forward (ephrin-B1-Fc) or reverse (EphB1-Fc) signaling, and the soluble monomeric EphB4 extracellular domain protein, that, simultaneously interfering with both signaling pathways, acts as EphB/ephrin-B antagonist.The blockade of the EphB/ephrin-B forward signaling by EphB4 and EphB1-Fc was ineffective against DSS-induced colitis while it evoked remarkable beneficial effects against TNBS colitis: it counteracted all the evaluated inflammatory responses and the changes elicited on splenic T lymphocytes subpopulations, without preventing the appearance of a splice variant of ephrin-B2 gene elicited by the haptenating agent in the colon. Interestingly, EphB4, preferentially displacing EphB4/ephrin-B2 interaction over EphB1/ephrin-B1 binding, was able to promote Tumor Necrosis Factor alpha (TNFα) release by splenic mononuclear cells in vitro. On the whole, the collected results point to a potential role of the EphB/ephrin-B system as a pharmacological target in intestinal inflammatory disorders and suggest that the therapeutic efficacy of its blockade seemingly works through the modulation of immune responses, independent of the changes at the transcriptional and translational level of EphB4 and ephrin-B2 genes.

An integrated rock-physics modeling workflow is discussed that aims at predicting the effective elastic moduli and density of a producing reservoir in response to pressure, porosity, and fluid-saturation changes, and that is suitable for application to compacting chalk reservoirs. A simple extended form of Nur's modified Voigt model is used to build the dry-rock elastic modulus and porosity relationship. Granular medium contact theory is used to model pressure change, and Gassmann's equation is used to model the fluid effect. A dynamic-compaction model from reservoir simulation is used to model porosity change due to compaction. The rock-physics model is calibrated at well locations from the Ekofisk Field in the North Sea; however, the absence of time-lapse logging makes the 4D calibration challenging. Effective fluid properties are calculated dynamically with the Fluid Acoustics for Geophysics (FLAG) software program, using inputs from the reservoir simulator and PVT measurements. For low water saturation (< 20%) and high-porosity (> 30%) rocks, the model predictions show very good correlation with measured data. The model underpredicts the sonic velocities for rocks with low porosity and high water saturation.

The existence of a cholinergic anti-inflammatory pathway negatively modulating the inflammatory and immune responses in various clinical conditions and experimental models has long been postulated. In particular, the protective involvement of the vagus nerve and of nicotinic Ach receptors (nAChRs) has been proposed in intestinal inflammation and repeatedly investigated in DSS- and TNBS-induced colitis. However, the role of α7 nAChRs stimulation is still controversial and the potential contribution of α4β2 nAChRs has never been explored in this experimental condition. Our aims were therefore to pharmacologically investigate the role played by both α7 and α4β2 nAChRs in the modulation of the local and systemic inflammatory responses activated in TNBS-induced colitis in mice and to assess the involvement of the spleen in nicotinic responses. To this end, TNBS-exposed mice were sub-acutely treated with various subcutaneous doses of highly selective agonists (AR-R17779 and TC-2403) and antagonists (methyllycaconitine and dihydro-β-erythroidine) of α7 and α4β2 nAChRs, respectively, or with sulfasalazine 50 mg/kg per os and clinical and inflammatory responses were evaluated by means of biochemical, histological and flow cytometry assays. α4β2 ligands evoked weak and contradictory effects, while α7 nAChR agonist AR-R17779 emerged as the most beneficial treatment, able to attenuate several local markers of colitis severity and to revert the rise in splenic T-cells and in colonic inflammatory cytokines levels induced by haptenization. After splenectomy, AR-R17779 lost its protective effects, demonstrating for the first time that, in TNBS-model of experimental colitis, the anti-inflammatory effect of exogenous α7 nAChR stimulation is strictly spleen-dependent. Our findings showed that the selective α7 nAChRs agonist AR-R17779 exerted beneficial effects in a model of intestinal inflammation characterized by activation of the adaptive immune system and that the spleen is essential to mediate this cholinergic protection.

Mesenteric ischemia-reperfusion (I/R)-induced injury targets primarily endothelial and epithelial cells, leading to a cascade of inflammatory events, eventually culminating in life-threatening syndromes. Hitherto, the role of Eph, the largest family of tyrosine kinase receptors, and of their cell-bound ephrin ligands, whose interaction generates a bidirectional signaling, is still debated in I/R injury. The aim of the present work was therefore to investigate the effects produced by unidirectional activation of forward signaling (administration of chimeric protein ephrinA1-Fc), of reverse signaling (EphA2-Fc), or inhibition of both signals (monomeric EphA2 and the protein-protein interaction inhibitor UniPR1331) on the local and systemic inflammatory responses triggered by mesenteric I/R in mice.When administered at 200 μg/kg i.v., ephrin-A1-Fc prevented intestinal and lung I/R-induced injury, decreasing in the pulmonary district leukocytes recruitment, IL-1β and TNFα levels, and EphA2 overexpression by mesenteric I/R. Blockade of Eph-ephrin signaling by equimolar EphA2 efficiently antagonized I/R-induced gut edema formation, an effect shared also by UniPR1331, mitigated lung mucosal injury, and counteracted the increase in pro-inflammatory cytokines levels. EphA2-Fc 180 μg/kg or equimolar Fc alone did not significantly modify the inflammatory responses to I/R.Our data suggest that the Eph-ephrin system is directly involved in the development of the acute inflammatory process activated in the gut by hypoxia-reoxygenation and in its amplification to distant organs, revealing that a fine pharmacological tuning of this signaling pathway may represent an attractive strategy to contain the I/R-induced inflammatory cascade.

This paper presents the challenge of the incremental launching of three viaducts of the Northern Marmara Motorway project in Istanbul Turkey. The incremental launching method (ILM) was pushed at its own limit to be adapted to this Viaduct. The deck, with 55 meter long spans, was moved by sliding on piers up to 82 meter high through a complex vertical and horizontal alignment.This paper gives an overview of this construction methods, and the specificity of these viaducts. In particular, specific procedures were implemented to control the behaviour of the piers during launching operations, due to their slenderness and their non-conventional anti-seismic design. Specific geometric checks were also necessary to follow the launching curve. Temporary structure associate to ILM will also be described in the paper: prefabrication yard, design and construction of the launching nose, choice and design of launching devices.

Located nearby the historic part of the city, the Vodafone Arena Stadium, replacing the former Besiktas JK Inonu stadium, stands out thanks to its remarkable covering of 26000m² that can shelter up to 42 000 spectators. The big lift method, used successfully in the last decades to lift lightweight and flexible structures composed by cables only, has been adapted for this project to lift a mixed structure, allying the stiffness of a highly hyperstatic steel frame and the shape- depending behavior of a cable structure. After being assembled on the ground, the structure was lifted on a distance of approximately 21m with 42 strand jacks, developing a total towing force of 7000t. Strict control procedures and geodetic checks were necessary to coordinate the 42 lifting points.The paper describes the general design approach and the specific site conditions; the construction method is detailed from both a calculation and an operational point of view.

In 2010, the world's largest optical permanent reservoir monitoring (PRM) system was installed in the southern part of the Norwegian North Sea at Ekofisk. The life-of-field seismic (LoFS) system consists of 3966 seabed multicomponent sensors along 200 km of mostly trenched fiber-optic seismic cables and covering about 60 km2 of Ekofisk field. Seismic data are acquired via a topside recording unit and a containerized source operated on a supply vessel. Six vintages of data were acquired between the end of 2010 and fall 2013. Different aspects of seismic operations at Ekofisk include seismic source, recording system, data transfer, quality control, and processing. One of the key factors in achieving the full value of a PRM system is to handle such operations in a safe, integrated, and efficient manner to deliver high-quality seismic volumes for interpretation with rapid turnaround. Key aspects of the 4D processing sequence include robustness and optimal turnaround. Integration of the different operational phases of the LoFS project and integration of expertise between client and contractor play a key role in delivering clean, well-resolvable 4D signals and low residual 4D noise with NRMS as low as 5%. The high-quality data delivered by operations and processing are now routinely used in well planning and reservoir-management workflows.

Background and Aims: Changes in gut serotonin content have been described in Inflammatory Bowel Disease and in different experimental models of colitis: the critical role of this monoamine in the pathogenesis of chronic gastrointestinal inflammation is gradually emerging. Aim of the present study was to evaluate the contribution of endogenous serotonin through the activation of its specific receptor subtypes to the local and systemic inflammatory responses in an experimental model of Inflammatory Bowel Disease. Methods: Colitis was induced by intrarectal 2,4,6-TriNitroBenzene Sulfonic acid in mice subacutely treated with selective antagonists of 5-HT1A (WAY100135), 5-HT2A (Ketanserin), 5-HT3 (Ondansetron), 5-HT4 (GR125487), 5-HT7 (SB269970) receptors and with 5-HT1A agonist 8-Hydroxy-2-(di-n-propylamino)tetralin. Results: Blockade of 5-HT1A receptors worsened TNBS-induced local and systemic neutrophil recruitment while 5-HT1A agonist delayed and mitigated the severity of colitis, counteracting the increase in colonic 5-HT content. On the contrary, blockade of 5-HT2A receptors improved global health conditions, reduced colonic morphological alterations, down-regulated neutrophil recruitment, inflammatory cytokines levels and colonic apoptosis. Antagonism of 5-HT3, 5-HT4 and 5-HT7 receptor sites did not remarkably affect the progression and outcome of the pathology or only slightly improved it. Conclusions: The prevailing deleterious contribution given by endogenous serotonin to inflammation in TNBS-induced colitis is seemingly mediated by 5-HT2A and, to a lesser extent, by 5-HT4 receptors and coexists with the weak beneficial effect elicited by 5-HT1A stimulation. These findings suggest how only a selective interference with 5-HT pro-inflammatory actions may represent an additional potential therapeutic option for intestinal inflammatory disorders.

Ulcerative colitis (UC) is associated with a substantial alteration of specific gut commensals, some of which may be involved in microbiota-mediated protection. In this study, microbiota cataloging of UC patients by 16S rRNA microbial profiling revealed a marked reduction of bifidobacteria, in particular the Bifidobacterium bifidum species, thus suggesting that this taxon plays a biological role in the aetiology of UC. We investigated this further through an in vivo trial by testing the effects of oral treatment with B. bifidum PRL2010 in a wild-type murine colitis model. TNBS-treated mice receiving 10(9) cells of B. bifidum PRL2010 showed a marked reduction of all colitis-associated histological indices as well as maintenance of mucosal integrity as it was shown by the increase in the expression of many tight junction-encoding genes. The protective role of B. bifidum PRL2010, as well as its sortase-dependent pili, appears to be established through the induction of an innate immune response of the host. These results highlight the importance of B. bifidum as a microbial biomarker for UC, revealing its role in protection against experimentally induced colitis.

This paper describes the implementation of a quantum chemistry code on a service-oriented grid where the computational workflow is spawned over multiple, geographically distributed, sites. The application porting over the grid and its extension as a web service over local and wide area networks is fully outlined. A description of the procedures developed for this experiment is given in full detail and the applicability of the methodology to similar codes in this scientific area is assessed. The new developed, grid-aware, application has been tested by performing a comprehensive set of benchmarks including quantum mechanical calculations on the water molecule. The obtained results of the benchmarks are reported and a full comparison with respect to the parallel execution of the same tests using the standard code is discussed in detail.

The equilibria between the different forms of the topotecan anticancer drug have been studied at moderately acidic and physiological pH by an integrated computational tool rooted in the density functional theory and its time-dependent extension together with the polarizable continuum model. The results allow an unbiased selection between the different possible tautomeric forms and provide invaluable complements to experimental data. The ultraviolet-visible topotecan spectrum, recorded at moderately acidic pH, is accurately reproduced only by TD-DFT computations including solvent effects. Comparison of the experimental and calculated bands of the UV-vis spectrum at physiological pH indicates the presence of an equilibrium among different forms that is tuned by the microenvironment embedding the drug. The quantitative agreement between TD-DFT/PCM computations and experiments allows the identification of unequivocal spectroscopic signatures for different forms of topotecan.

In this work, the effect of natural fractures on the azimuthal response from structured reservoirs encased within carbonate rocks is investigated through forward modeling. Two fractured carbonate reservoirs are examined: the first one is composed by sediments nearly flat; the second one is in an area with reflectors having dip up to twenty degrees. When modeling fracture behavior, even if fractures are sub-vertical, it is usual to suppose that they are vertical. For dipping reflectors, even if fractures are supposed to be vertical, they are not normal to vertical versus the dipping reflectors. Thus, the reflections from a dipping reflector above vertical fractures are quite similar to reflections from a flat reflector with inclined fractures below. We compare synthetic seismic data from two different models having respectively vertical fractures and sub-vertical fractures (with an inclination of 70o). Fracture inclination perturbations give azimuthal variations especially on results of converted waves. Indeed, reflections from dipping interfaces present azimuthal variations of amplitudes even for isotropic media. For a model composed by several dipping layers, we investigate the combined effects of fractures and dipping reflectors. In particular, we discuss Amplitudes versus Offset and Azimuth (AVOA) of converted waves that, at present, have been used just for their splitting and we show how AVOA can help fracture characterization.

In this paper Time-Dependent Density Functional Theory (TD-DFT) with Becke's three-parameter hybrid method using the Lee–Yang–Parr correlation functional (B3LYP) in conjunction with different basis sets is applied to calculate the solvatochromic shift on the lowest singlet transition of formaldehyde in vacuum and in solution. Our results, in excellent agreement with solvent excitation energy shift of acetone in water at 298–300 K (no experimental data on formaldehyde in water are available so far) and with previous high level quantum chemical calculations, help in appreciating the potentialities of the combined DFT/PCM approach on aquo-complexes for the study of structural and spectroscopic properties of molecule in solution.

In recent years multicomponent 3D seismic data have demonstrated their usefulness for characterizing fractured reservoirs. Many theoretical and field studies have shown that variation of attributes (such as velocity, amplitude, and frequency of P-wave data acquired along different source to receiver paths), can be used as an indicator of azimuthal anisotropy. Lateral heterogeneity encountered by the different azimuth source-receiver raypaths could give rise to azimuthal variations in traveltime and/or transmission characteristics, and thus masquerade as azimuthal anisotropy. To remove this ambiguity, mode-converted split shear waves can be employed. S-wave splitting across a fractured medium is a well studied and understood phenomenon that exploits the traveltime delay between the fast and the slow S-waves, and their polarization azimuths to infer fracture properties.

Summary An integrated rock physics modeling framework is discussed in this paper that aims at predicting the effective elastic moduli and density of a producing reservoir in response to pressure, porosity and fluid saturation changes, and is suitable for application to compacting chalk reservoirs. A simple extended form of Nur’s modified Voigt model is used to build the dry rock elastic modulus and porosity relationship. Granular medium contact theory is used to model pressure change and Gassmann’s equation is used to model the fluid effect. A dynamic compaction model from reservoir simulation is used to model porosity change due to compaction. The rock physics model is calibrated at well locations from the Ekofisk field in the North Sea, however the absence of time-lapse logging makes the 4D calibration challenging. Effective fluid properties are calculated dynamically with the FLAG software program using inputs from the reservoir simulator and PVT measurements. For low water saturation ( 30%) rocks the modeled results show very good correlation with measured data. The model under-predicts the sonic velocities for rocks with low porosity and high water saturation.

The world’s largest optical Permanent Reservoir Monitoring (PRM) system was installed at Ekofisk in 2010. The Ekofisk LoFS system consists of nearly 4000 seabed multicomponent sensors and a top side recording unit provided by Optoplan and a containerized source operated on a supply vessel. After the first 4 surveys, all the sensors were still active and very high repeatability (3-4% NRMS) had been achieved. One of the key factors to unraveling full value of a PRM system is to be able to handle seismic operations in a safe, integrated and efficient manner in order to deliver high quality seismic volumes for interpretation in a rapid turnaround. In this paper, we present the different aspects of seismic operations at Ekofisk: seismic source, recording system and data transfer, QC and processing, and discuss how their integration enables timely delivery of high quality 4D seismic products.

In this paper, we take a closer look at some of the technology used and the research carried out over the first two years on the Ekofisk PRM project. This includes QC issues for the acquisition; signal processing issues (such as 4D robustness of rotations; interference and VZ noise methods; surface consistent amplitude corrections); sensor performance and solutions to problems found; optimal imaging solutions such as FWI. Furthermore we report on the evolution of the Ekofisk operations in the coming months and discuss opportunities and possibilities arising via enhanced acquisition technology, improved processing and imaging, data management, and the potential for other reservoir oriented methods such as passive seismic monitoring.

The world’s largest optical Permanent Reservoir Monitoring (PRM) system was installed at Ekofisk in 2010. The system consists of nearly 4000 seabed multicomponent sensors, a top side recording unit installed on a platform and a containerized source operated on a supply vessel. After 3 years and 4 surveys, all the sensors are still active and very high repeatability (3-4% NRMS) has been achieved. This paper describes the different aspects and advantages of the project, including installation, data flow, acquisition and processing, discusses the quality of the data and how LoFS data are routinely used in well planning and reservoir management workflows.

We present the 4D processing sequence for the Ekofisk Permanent Reservoir Monitoring project. Four vintages of data were acquired between the end of 2010 and summer 2012 using 200km of trenched fibre optic seismic cables covering about 60 km˛ and with a total of 3966 4C sensor stations. We discuss key aspects of the processing sequence, turnaround, and the integration of expertise between client and contractor. This delivers outstanding seismic repeatability with clean, well resolvable 4D signals and low residual 4D noise (NRMS of 3-5%).

Summary We illustrate the applications on real data sets of three algorithms of multicomponent seismic processing implemented by means of quaternion algebra i.e.: velocity analysis, deconvolution, and Rayleigh wave extraction. First we present an application of quaternion velocity analysis on multicomponent traces, which results in an improved resolution and it allows us to discern on a single velocity panel the different wave trends (P, PS, converted waves) simultaneously. Then we present an application of quaternion deconvolution, that represents an extension of the classical Wiener deconvolution, and takes advantage of the vectorial nature of the wave-field, performing better than scalar filters. Finally, we show an application of a quaternion procedure that extracts a single Rayleigh wave mode on a multicomponent land data set.

Being a highly compacted chalk reservoir, Ekofisk is a well known example of a field showing strong time lapse effects; as a result of compaction, the water bottom has subsided by over 9 m since the start of production in 1971. Five 4D seismic surveys have been shot on the area to improve understanding of reservoir behaviour. For instance, these multiple monitors sampled the evolving distribution of water and the effects of fault compartmentalisation on reservoir fluid flow. Although an extensive use of the time shift estimated at the top of the reservoir has been made in the past, it has so far been difficult to invert for subtle time lapse effects within the reservoir and therefore to identify which part of the reservoir undergoes 4D changes with sufficient accuracy and confidence. When several seismic vintages are available, it is possible to improve the precision of the inverted 4D attributes by performing an inversion that minimises at the same time the differences between all possible combinations of pairs of datasets. This sort of multi-vintage warping enables improved images showing 4D changes within the Ekofisk reservoirs to be obtained. These images can improve the reservoir understanding on a scale, where a number of slides, slumps and debris flows create a rather heterogeneous three-dimensional pattern and sometimes make fluid flow understanding and correlation between wells problematic.

The ultraviolet-visible absorption spectrum of camptothecin (CPT) has been been recorded in aqueous solution at pH 5.3, where the equilibrium among the different CPT forms is shifted toward the lactonic one. Time-dependent density functional theory (TD-DFT) computations lead to a remarkable reproduction of the experimental spectrum only upon addition of explicit water molecules in interaction with specific moieties of the camptothecin molecule. Molecular dynamics (MD) simulations enforcing boundary periodic conditions for CPT embedded with 865 water molecules, with a force field derived from DFT computations, show that the experimental spectrum is due to the contributions of CPT molecules with different solvation patterns. A similar solvent effect is observed for several CPT derivatives, including the clinically relevant SN-38 and topotecan drugs. The quantitative agreement between TD-DFT/MD computations and experimental data allow us to identify specific spectroscopic signatures diagnostic of the drug environment and to develop procedures that can be used to monitor the drug-DNA/protein interaction.

Time-lapse seismic has proven to be a useful tool for reservoir management and is increasingly becoming a standard practice to monitor production, identify undrained resources, accelerate the production of reserves. Dedicated inversion tools have been developed to obtain time-lapse seismic images to provide in a reasonable amount of time reliable 4D signal in a shared earth model. As an efficient substitute to full 4D inversion, a series of tools sharing the denomination of ‘warping’ have been developed in order to produce relevant 4D difference volumes. These include correlation-based methods, timeshift non-linear inversions and relative velocity (or timestrain) non linear inversions. Standard correlation-based methods and non-linear time-shift inversion are mainly used to align base and monitor surveys and generate timeshifts which may sometimes be used interpretatively but in general have insufficient resolution and stability to be of interest as 4D reservoir attributes. Even after alignment the difference volumes, while characteristic of changes in the reservoir, are difficult to interpret quantitatively, due to the band-limited nature of seismic data. Conversely, when formulated as a non-linear inversion to retrieve interval quantities like relative velocity changes or time strain, the warping obtains information which can be easily integrated in the reservoir models, at least for the relatively numerous cases where the 1D-approximation can be used on post-migration time data, typically from PSTM or PSDM imaging. However this inversion formulation is seriously ill-posed, which thus requires careful regularisation and the integration of geosciences at every stage of the inversion. Conversely the regularisation still allows working trace by trace. This is computationally efficient as it does not require inversion of the 3D dataset as a whole. As an application three examples are discussed. Case A is an HPHT reservoir with very low signal to noise ratio and problematic repeatability close to the platform; in this case dedicated warping allows obtaining stable 4D signal at the reservoir level as well in the overburden. Case B is a turbiditic reservoir where a 4D signal due to gas either injected or coming out of solution under depletion is measured. Case C is a stress-sensitive reservoir where a stable 4D signal inverted at the reservoir level correlates very well with production data.

This work is focussed on the theoretical investigation of the observed fragmentation after the resonant electron attachment to gas-phase β-D-deoxyribose. The collision energy of the incident electron is kept below 20 eV and both the furanosic and the pyranosic forms of the gaseous target are analyzed. All the transient negative ions associated to shape resonances are characterized in their energetics and spatial features, all pointing to highly selective bond-breaking resonant processes. The present results, when compared with the available experiments on gas-phase β-D-deoxyribose and with the findings on the analogous conformers from the previously studied β-D-ribose, offer new insights into the manifold fragmentation pathways occurring in biomolecules after electron attachment. © 2008 Wiley Periodicals, Inc. Int J Quantum Chem, 2008

Electron attachment experiments are carried out on the beta-d-ribose molecule in the gas phase for the energy region around 8 eV, and clear fragmentation products are observed for different mass values. A computational analysis of the relevant dynamics is also carried out for the beta-d-ribose in both the furanosic and pyranosic form as gaseous targets around that energy range. The quantum scattering attributes obtained from the calculations reveal in both systems the presence of transient negative ions (TNIs). An analysis of the spatial features of the excess resonant electron, together with the computation and characterization of the target molecular normal modes, suggests possible break-up pathways of the initial, metastable molecular species.