424 research outputs found
Preliminary investigation on the geological potential for underground hydrogen storage (uhs) in saline formations in italy
In the last years, energy transition from fossil fuels to renewable resources has been largely acknowledged as a necessity to reduce emissions of greenhouse gases in the atmosphere. Hydrogen, the simplest element on Earth, can play an important role in this transition. It is not as an energy source but rather as an energy carrier: in laymanâs terms, electricity is converted in chemical energy, which can then be converted again in electricity or in green methane, if combined with carbon dioxide. Because hydrogen can be obtained from the excess of electricity produced from power plants or from renewable energy sources, such as solar panels or wind mills, it is a clean and sustainable form of energy, to be stored and used when needed. As a consequence, a key issue is hydrogen storage. Large metallic containers are typically used to this end but their capacity is limited. Given the increasing hydrogen production and perspective large use, the only viable alternative is underground storage in geological formations, which can be depleted hydrocarbon reservoirs, deep saline aquifers, or cavities in salt domes. Underground hydrogen storage (UHS) is already in use in various countries and mostly in salt caverns artificially made by circulation of fresh water. In the Italian territory there are several areas where saline deposits are both observable as outcrops or detected deep in the subsoil. Their thickness and their geological, petrophysical and mechanical characteristics vary from one area to another depending on the depositional conditions, which favored the formation of different sedimentary facies. These characteristics have a strong impact on the decision to convert a saline dome into a hydrogen storage and, therefore, they should be thoroughly investigated. The aim of this work is to map the salt formations mapped on the Italian territory and to preliminarily assess their potential on the basis of the geological characteristics for a possible future use as underground hydrogen storages
Quartz-amethyst hosted hydrocarbon-bearing fluid inclusions from the green ridge breccia in the snoqualmie granite, North Cascades,WA, USA
We wish to acknowledge the constructive criticisms made by the three anonymous reviewers.Their suggestions and comments greatly improved the first version of the manuscript.Peer reviewedPublisher PD
Gridding Effects on CO2 Trapping in Deep Saline Aquifers
Three-dimensional numerical models of potential underground storage and compositional simulation are a way to study the feasibility of storing carbon dioxide in the existing geological formations. However, the results of the simulations are affected by many numerical parameters, and we proved that the refinement of the model grid is one of them. In this study, the impact of grid discretization on CO2 trapping when the CO2 is injected into a deep saline aquifer was investigated. Initially, the well bottom-hole pressure profiles during the CO2 injection were simulated using four different grids. As expected, the results confirmed that the overpressure reached during injection is strongly affected by gridding, with coarse grids leading to non-representative values unless a suitable ramp-up CO2 injection strategy is adopted. Then, the same grids were used to simulate the storage behavior after CO2 injection so as to assess whether space discretization would also affect the simulation of the quantity of CO2 trapped by the different mechanisms. A comparison of the obtained results showed that there is also a significant impact of the model gridding on the simulated amount of CO2 permanently trapped in the aquifer by residual and solubility trapping, especially during the few hundred years following injection. Conversely, stratigraphic/hydrodynamic trapping, initially confining the CO2 underground due to an impermeable caprock, does not depend on gridding, whereas significant mineral trapping would typically occur over a geological timescale. The conclusions are that a fine discretization, which is acknowledged to be needed for a reliable description of the pressure evolution during injection, is also highly recommended to obtain representative results when simulating CO2 trapping in the subsurface. However, the expedients on CO2 injection allow one to perform reliable simulations even when coarse grids are adopted. Permanently trapped CO2 would not be correctly quantified with coarse grids, but a reliable assessment can be performed on a small, fine-grid model, with the results then extended to the large, coarse-grid model. The issue is particularly relevant because storage safety is strictly connected to CO2 permanent trapping over time
Application of A* algorithm for tortuosity and effective porosity estimation of 2D rock images
Characterization and understanding of fluid flow phenomena in un-derground porous media at the micro and macro scales is fundamental in reser-voir engineering for the definition of the optimal reservoir exploitation strategy. Laboratory analyses on rock cores provide fundamental macroscale parameters such as porosity, absolute and relative permeability and capillary pressure curves. In turn, macroscale parameters as well as flow behavior, are strongly af-fected by the micro geometrical features of the rock, such as pore structure, tor-tuosity and pore size distribution. Therefore, a thorough comprehension of sin-gle and multiphase flow phenomena requires analyses, observations and charac-terization at the micro scale. In this paper we focus on the analysis of a 2D bina-ry image of a real rock thin section to characterize the pore network geometry and to estimate tortuosity, effective porosity and pore size distribution. To this end, a geometrical analysis of the pore structure, based on the identification and characterization of the set of the shortest geometrical pathways between inlets and outlets pairs, is implemented. The geometrical analysis is based on the A* path-finding algorithm derived from graph theory. The results provided by the geometrical analysis are validated against hydrodynamic numerical simulation via the Lattice Boltzmann Method (LBM), which is well suited for simulating fluid flow at the pore-scale in complex geometries. The selected rock for this analysis is Berea sandstone, which is recognized as a standard rock for various applications such as core analysis and flooding experiment. Results show that the path-finding approach provides reasonable and reliable estimates of tortuos-ity and can be successfully applied for analyzing the distribution of effective pore radius, as well as for estimating the effective porosity
Improved lithology prediction in channelized reservoirs by integrating stratigraphic forward modelling: towards improved model calibration in a case study of the Holocene Rhine-Meuse fluvio-deltaic system.
Stratigraphic forward modelling (SFM) provide the means to produce geologically coherent and realistic models. In this paper, we demonstrate the possibility of matching lithological variability simulated with a basin-scale advection-diffusion SFM to a data-rich real-world setting, i.e. the Holocene Rhine-Meuse fluvio-deltaic system in the Netherlands. SFM model calibration to real-world data in general has proven non-trivial. This study focuses on a novel inversion process constrained by the top surface and the sand proportion observed at specific pseudo-wells in the study area. Goodness-of-fit expressed by a new fitness function, gives the error calculated as the average of two calibration constraints. Computational efficiency was increased significantly by implementing a new optimization process in two hierarchical steps: a) optimization in terms of sediment load and discharge, which are the most influential parameters having the largest uncertainty and b) optimization with respect to the remaining uncertain parameters, these being sediment transport parameters. The calibration process described allows for the most optimal combination of achieving acceptable levels of goodness-of-fit, feasible runtimes and multiple (non-unique) solutions to obtain synthetic stratigraphic output best matching real-world datasets.
By removing model realizations which are geologically unrealistic, calibrated SFM models provide a multiscale stratigraphic framework for reconstructing static models of reservoirs which are consistent with the palaeogeographic layout, basin-fill history and external drivers (e.g. sea level, sediment supply). The static reservoir models that are matched with highest certainty therefore contain the highest geological realism and may be used to improve deep subsurface reservoir or aquifer property prediction.
The new methodology was applied to the well-established Holocene Rhine-Meuse dataset which allows a rigorous testing of the optimization and the calibrated SFM allows investigation of controls of the Holocene development on the sedimentary system
Clinical similarity of biosimilar ABP 501 to adalimumab in the treatment of patients with moderate to severe plaque psoriasis: A randomized, double-blind, multicenter, phase III study
Background ABP 501 is a biosimilar of adalimumab. Objective We sought to compare the efficacy and safety of ABP 501 with adalimumab. Methods This 52-week, double-blind study randomized patients with moderate to severe psoriasis to ABP 501 or adalimumab. At week 16, those with 50% or more improvement in Psoriasis Area and Severity Index score from baseline on ABP 501 continued the same treatment, whereas adalimumab-treated patients were rerandomized to adalimumab or ABP 501. Clinical similarity in Psoriasis Area and Severity Index percent improvement from baseline to week 16 (primary end point) was established if the point estimate of treatment difference and its 2-sided 95% confidence interval between groups was within equivalence margin of ±15. Patients, including those undergoing a single transition at week 16, were evaluated for safety and immunogenicity. Results Psoriasis Area and Severity Index percent improvement at week 16 was 80.9 for ABP 501 and 83.1 for adalimumab (least-square mean difference â2.18 [95% confidence interval â7.39 to 3.02]). Adverse events (67.2% [117/174] vs 63.6% [110/173]) and antidrug antibody incidence (55.2% [96/174] vs 63.6% [110/173]) for ABP 501 vs adalimumab were similar. Safety, including immunogenicity, was similar among groups after single transition (week 20). Limitations The 52-week data are not reported here. Conclusions ABP 501 was shown to be clinically similar to adalimumab. Safety and immunogenicity were not impacted immediately after single transition (adalimumab to ABP 501)
Identification of a novel lysophospholipid acyltransferase in Saccharomyces cerevisiae
Journal of Biological Chemistry, 282(42): pp. 30562-30569.The incorporation of unsaturated acyl
chains into phospholipids during de novo
synthesis is primarily mediated by the 1-acylsn-
glycerol-3-phosphate acyltransferase
reaction. In S. cerevisiae, Slc1 has been shown
to mediate this reaction but distinct activity
remains after its removal from the genome. To
identify the enzyme that mediates the
remaining activity, we performed synthetic
genetic array analysis using a slc1Î strain. One
of the genes identified by the screen, LPT1, was
found to encode for an acyltransferase that uses
a variety of lysophospholipid species, including
1-acyl-sn-glycerol-3-phosphate. Deletion of
LPT1 had a minimal effect on 1-acyl-snglycerol-
3-phosphate acyltransferase activity
but over-expression increased activity 7-fold.
Deletion of LPT1 abrogated the esterification of
other lysophospholipids and over-expression
increased lysophosphatidylcholine
acyltransferase activity 7-fold. The majority of
this activity co-purified with microsomes. To
test the putative role for this enzyme in
selectively incorporating unsaturated acyl
chains into phospholipids, in vitro, substrate
concentration series experiments were
performed with the four acyl-CoA species
commonly found in yeast. While the saturated
palmitoyl-CoA and stearoyl-CoA showed a
lower apparent Km, the monounsaturated
palmitoleoyl-CoA and oleoyl-CoA showed a
higher apparent Vmax. Arachidonyl-CoA,
although not abundant in yeast, also had a high
apparent Vmax. Pulse-labeling of lpt1Î strains
showed a 30% reduction in [3H]oleate
incorporation into phosphatidylcholine only.
Therefore, Lpt1p, a member of the membrane
bound o-acyltransferase gene family, seems to
work in conjunction with Slc1 to mediate the incorporation of unsaturated acyl-chains into
the sn-2 position of phospholipids
Underground Hydrogen Storage Safety: Experimental Study of Hydrogen Diffusion through Caprocks
Underground Hydrogen Storage (UHS) provides a large-scale and safe solution to balance
the fluctuations in energy production from renewable sources and energy consumption but requires
a proper and detailed characterization of the candidate reservoirs. The scope of this study was to
estimate the hydrogen diffusion coefficient for real caprock samples from two natural gas storage
reservoirs that are candidates for underground hydrogen storage. A significant number of
adsorption/desorption tests were carried out using a Dynamic Gravimetric Vapor/Gas Sorption
System. A total of 15 samples were tested at the reservoir temperature of 45 °C and using both
hydrogen and methane. For each sample, two tests were performed with the same gas. Each test
included four partial pressure steps of sorption alternated with desorption. After applying
overshooting and buoyancy corrections, the data were then interpreted using the early time
approximation of the solution to the diffusion equation. Each interpretable partial pressure step
provided a value of the diffusion coefficient. In total, more than 90 estimations of the diffusion
coefficient out of 120 partial pressure steps were available, allowing a thorough comparison between
the diffusion of hydrogen and methane: hydrogen in the range of 1 Ă 10â10 m2/s to 6 Ă 10â8 m2/s and
methane in the range of 9 Ă 10â10 m2/s to 2 Ă 10â8 m2/s. The diffusion coefficients measured on wet
samples are 2 times lower compared to those measured on dry samples. Hysteresis in hydrogen
adsorption/desorption was also observed
Equine Herpesvirus Protein E10 Induces Membrane Recruitment and Phosphorylation of Its Cellular Homologue, Bcl-10
v-E10, a caspase recruitment domain (CARD)-containing gene product of equine herpesvirus 2, is the viral homologue of the bcl-10 protein whose gene was found to be translocated in mucosa-associated lymphoid tissue (MALT) lymphomas. v-E10 efficiently activates the c-jun NH2-terminal kinase (JNK), p38 stress kinase, and the nuclear factor (NF)-ÎșB transcriptional pathway and interacts with its cellular homologue, bcl-10, via a CARD-mediated interaction. Here we demonstrate that v-E10 contains a COOH-terminal geranylgeranylation consensus site which is responsible for its plasma membrane localization. Expression of v-E10 induces hyperphosphorylation and redistribution of bcl-10 from the cytoplasm to the plasma membrane, a process which is dependent on the intactness of the v-E10 CARD motif. Both membrane localization and a functional CARD motif are important for v-E10âmediated NF-ÎșB induction, but not for JNK activation, which instead requires a functional v-E10 binding site for tumor necrosis factor receptorâassociated factor (TRAF)6. Moreover, v-E10âinduced NF-ÎșB activation is inhibited by a dominant negative version of the bcl-10 binding protein TRAF1, suggesting that v-E10âinduced membrane recruitment of cellular bcl-10 induces constitutive TRAF-mediated NF-ÎșB activation
Dupilumab significantly improves sleep in adults with atopic dermatitis: results from the 12-week placebo-controlled period of the 24-week phase 4 randomized double-blinded placebo-controlled DUPISTAD study
BACKGROUND
Sleep disturbance is a prominent symptom of atopic dermatitis (AD) and can result in insomnia, daytime fatigue, drowsiness, reduced productivity and impaired quality of life (QoL).
OBJECTIVES
The Dupilumab Effect on Sleep in AD Patients (DUPISTAD) phase IV randomized double-blinded placebo-controlled study evaluated the impact of dupilumab treatment on sleep and other patient- and physician-reported outcomes.
METHODS
Adults with moderate-to-severe AD were randomized 2 : 1 to dupilumab 300â
mg once every 2 weeks (q2w) or placebo for 12Â weeks; concomitant topical corticosteroids were permitted. Patients subsequently entered an open-label phase and received dupilumab 300â
mg q2w for a further 12 weeks. The primary endpoint was the percentage change in sleep quality from baseline to week 12, assessed using a novel numeric rating scale (NRS). Secondary and exploratory endpoints included percentage change in peak pruritus NRS (PP NRS), change in SCORing Atopic Dermatitis (SCORAD), SCORAD sleep visual analogue scale (VAS), Eczema Area and Severity Index, Patient-Reported Outcomes Measurement Information System (PROMIS) sleep-related impairment T-score and the Epworth Sleepiness Scale. Sleep diary and wrist actigraphy measurements were recorded throughout the study.
RESULTS
In total, 127 patients received dupilumab and 61 patients received placebo. Demographic and baseline disease characteristics were balanced between groups. Sleep quality NRS significantly improved in patients treated with dupilumab by week 12 vs. placebo [least squares mean of the difference (LSMD) -15.5%, P < 0.001]. PP NRS (LSMD -27.9%, P < 0.001), SCORAD (LSMD -15.1, P < 0.001), SCORAD sleep VAS (LSMD -2.1, P < 0.001) and PROMIS T-score (LSMD -3.6, P < 0.001) were also significantly improved at week 12 with dupilumab vs. placebo. The overall percentage of patients reporting treatment-emergent adverse events was lower in the dupilumab group (56.7%) than in the placebo group (67.2%).
CONCLUSIONS
Dupilumab significantly improved sleep quality and perception of sleep continuity, itch, metrics of AD severity and QoL in adults with moderate-to-severe AD, with an acceptable safety profile compared with placebo
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