The permeability of natural gas hydrate (NGH) turbidite reservoirs typically exhibits significant anisotropy, with anisotropy being a crucial basis for evaluating reservoir production. The presence ...of hydrates, as a crucial constituent of the solid framework, not only impacts the overall permeability but also influences the permeability anisotropy. To investigate the saturation sensitivity of permeability anisotropy, a series of simulations are performed by integrating particle flow and computational fluid dynamics methods to construct the homogeneous and layered numerical samples and compute the evolution of permeability anisotropy. It is shown that the permeability is isotropic for homogeneous sediments and the isotropy remains unchanged regardless of variations in hydrate saturation. The permeability of layered sediments, in contrast, exhibits significant anisotropy due to the presence of dominant channels within the coarse layer. For uniformly distributed hydrates, the more effective blockage in coarse layers results in a reduction in anisotropy. While for preferentially distributed hydrates, the excess blocking of coarse layers makes the dominant channels transfer to the fine layers, the further blocking causes a U-shaped anisotropy–saturation curve characterized by a decrease–increase transformation. During the reservoir production process, the preponderance channels blocked by hydrates will be cleared and the horizontal permeability will significantly increase. As a result, the production efficiency of horizontal wells may exceed expectations. The findings offer a parameter support for production estimation and environmental assessment.
To investigate the predictive value of baseline C-reactive protein (CRP) levels on the efficacy of chemotherapy plus immune checkpoint inhibitors (ICI) in patients with advanced lung squamous cell ...carcinoma (LSCC).
In this retrospective multicenter study spanning from January 2016 to December 2020, advanced LSCC patients initially treated with chemotherapy or a combination of chemotherapy and ICI were categorized into normal and elevated CRP subgroups. The relationship between CRP levels and treatment outcomes was analyzed using multivariate Cox proportional hazards models and multivariate logistic regression, focusing primarily on the progression-free survival (PFS) endpoint, and secondarily on overall survival (OS) and objective response rate (ORR) endpoints. Survival curves were generated using the Kaplan-Meier method, with the log-rank test used for comparison between groups.
Of the 245 patients evaluated, the 105 who received a combination of chemotherapy and ICI with elevated baseline CRP levels exhibited a significant reduction in PFS (median 6.5 months vs. 11.8 months, HR, 1.78; 95% CI: 1.12-2.81; p = 0.013) compared to those with normal CRP levels. Elevated CRP was identified as an independent risk factor for poor PFS through multivariate-adjusted analysis. However, among the 140 patients receiving chemotherapy alone, baseline CRP levels did not significantly influence PFS. Furthermore, within the combination therapy group, there was a notable decrease in the ORR (51% vs. 71%, p = 0.035), coupled with a significantly shorter OS (median 20.9 months vs. 31.5 months, HR, 2.24; 95% CI: 1.13-4.44; p = 0.033).
In patients with advanced LSCC, elevated baseline CRP levels were identified as an independent predictive factor for the efficacy of combination therapy with chemotherapy and ICI, but not in chemotherapy alone. This suggests that CRP may be a valuable biomarker for guiding treatment strategies.
Pterostilbene, being extracted from many plants, has significant biological activities in preventing cancer, diabetes, and cardiovascular diseases so as to have great potential applications in ...pharmaceutical fields. But the poor solubility and stability of pterostilbene strictly restrained its applications. As a good protection and oral delivery system, an optimal nanoemulsion for pterostilbene was developed by using low-energy emulsification method. Systematic pseudo-ternary phase diagrams have been studied in optimization of nanoemulsion formulations. The prepared pterostilbene nanoemulsion was characterized by transmission electron microscope, Fourier transform Raman spectrum, and laser droplet size analyzer. Nanoemulsion droplets are circular with smooth margin, and the mean size is 55.8 ± 10.5 nm. The results illustrated that the nanoemulsion as oral delivery system dramatically improved the stability and solubility of pterostilbene, and
in vitro
release of pterostilbene was significantly improved (96.5% in pH 3.6 buffer; 13.2% in pH 7.4 buffer) in comparison to the pterostilbene suspension (lower than 21.4% in pH 3.6 buffer; 2.6% in pH 7.4 buffer).
Abstract It is still a challenge to develop electrocatalyst for the efficient adsorption and conversion of organic molecule in aqueous media. Herein, a hetero‐interface structure based on CuO@Ni(OH) ...2 is rationally designed to enhance the performance of benzyl alcohol oxidation to benzoic acid. A high Faradaic efficiency of 99% and the yield of 3.09 mmol cm −2 h −1 are achieved at 1.70 V versus reversible hydrogen electrode, outperforming the previously reported electrocatalysts. Furthermore, a membrane‐free flow electrolyzer was assembled based on CuO@Ni(OH) 2 hetero‐interface, exhibiting a much high yielding of benzoic acid (6.73 mmol cm −2 h −1 ) and hydrogen (0.35 L cm −2 h −1 ) with excellent stability. Both experimental data and density functional theory calculations verify that the electron is tend to accumulate at the hetero‐interface, thus accelerating the adsorption of reactant and intermediate and reducing the energy barrier of the conversion of benzyl alcohol to benzoic acid.
► C4-HSL may act as an elicitor from bacteria in plant. ► Ca2+ signaling participates in the sensing of plant cells to bacterial QS signals. ► C4-HSL can promote a transient elevation in Ca2+cyt.
...N-acyl-l-homoserine lactones (AHLs) are quorum sensing (QS) signal molecules that are commonly used in gram-negative bacteria. Recently, it has become evident that AHLs can influence the behavior of plant cells. However, little is known about the mechanism of the plants’ response to these bacterial signals. Calcium ions (Ca2+), ubiquitous intracellular second messengers, play an essential role in numerous signal transduction pathways in plants. In this study, the cytosolic free Ca2+ concentration (Ca2+cyt) was measured by a luminometric method in the excised root cells of Arabidopsis plants that were treated with N-butyryl-homoserine lactone (C4-HSL). There was a transient and immediate increase in Ca2+cyt levels, and the highest level (0.4μM), approximately 2-fold higher than the basal level, was observed at the 6th second after the addition of 10μM C4-HSL. Pretreatments with La3+, verapamil or ethylene glycol tetraacetic acid (EGTA) inhibited the increase in Ca2+cyt caused by C4-HSL, whereas it remained unaffected by pretreatment with Li+, indicating that the Ca2+ contributing to the increase in Ca2+cyt was mobilized from the extracellular medium via the plasma membrane Ca2+ channels but not from the intracellular Ca2+ stores. Furthermore, electrophysiological approaches showed that the transmembrane Ca2+ current was significantly increased with the addition of C4-HSL. Taken together, our observations suggest that C4-HSL may act as an elicitor from bacteria to plants and that Ca2+ signaling participates in the ability of plant cells to sense the bacterial QS signals.
Perovskite quantum dots (PQDs) have attracted extensive attention for various applications due to their hallmark optoelectronic properties. However, PQD gain materials are usually needed to be ...integrated with an external cavity to acquire effective optical feedback for lasing oscillation, which generally suffers from stringent fabrication procedures and the destruction of their pristine gain performance. In this work, we propose an approach to realize a new class of random lasers that are constructed by in situ precipitating perovskite quantum dots (PQDs) in metal–organic frameworks (MOFs). Such random lasers make full use of the combined merits of MOFs showing a high refractive index and a broad transmission window and that of PQDs exhibiting high optical gain. A lead-based MOF is utilized as a matrix, which allows us to grow PQDs at the Pb2+ sites in situ and thus produce high-density PQDs gain in MOFs. We experimentally demonstrate low-threshold multicolor random lasers achieved in the visible spectral range with different wavelengths through compositional modulation in the nanoporous environment of MOF nanostructures and illustrate potential applications of the developed PQDs@MOFs random laser as the illumination source in the speckle-free optical imaging. This study will pave the way for the construction of perovskite-based lasing in multifunctional systems.
The Neogene fluvial–lacustrine sediments of the Tianshui Basin provide records of the interactions among tectonic activity, and climatic and ecological changes on the northeastern Tibetan Plateau (NE ...TP), from ∼12.4 to 2.6 Ma. We investigated the
n
-alkane record of a sedimentary sequence from the Tianshui Basin, which reveals shifts in the productivity and sources of
n
-alkanes. The productivity of
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-alkanes doubled many times during ∼4.2–3.2 Ma, accompanied by the increased contribution from aquatic plants; in addition, non-emergent macrophytes occurred sporadically after ∼4.2 Ma but became a significant
n
-alkane source after ∼3.2 Ma. Changes in the inferred Late Miocene ecology of the region are consistent with the major climate transition in response to global cooling. The oscillations of the types and concentrations of
n
-alkanes during 4.2–3.2 Ma were likely related to the evolution of the East Asian monsoon (EAM), driven by the tectonic uplift of NE TP and global cooling. The major increase in aquatic plants and biological productivity of this region at ∼3.2 Ma may have been caused by the strengthening of the East Asian summer monsoon (EASM) and the regional tectonic uplift.
A fast radiative decay process for long‐wavelength molecular light‐emitters is vital to achieving a high emission efficiency by outcompeting the nonradiative decay imposed by the energy‐gap law. An ...ensuing short emission lifetime is also beneficial for fabricating high‐performance organic light‐emitting diodes. Herein a series of half‐lantern dinuclear platinum(II) complexes is reported, which shows high‐efficiency deep red phosphorescence (λem > 660 nm). The molecules are designed to have a cofacially aligned structure featuring short Pt–Pt distances of 2.80–2.83 Å by using 10H‐pyrido3,2‐b1,4benzoxazine (PyXZ) as the rigid bridges, which are revealed by single crystal X‐ray diffraction analysis. Together with the strong electron‐donating property of PyXZ bridges, the metallophilic interaction endows low‐energy triplet excited states with mixed metal–metal‐to‐ligand charge‐transfer (3MMLCT) and ligand‐to‐ligand charge‐transfer (3LLCT) characters. The deep red devices based on the diplatinum(II) complexes show maximum external quantum efficiencies (EQEs) up to 21.8%. The EQE of 19.4% and operational lifetime (LT85) of 334 h (the operational time after which the luminance drops to 85% of the initial value) at a luminance of 1000 cd m−2 promise the pratical use of these complexes.
A series of half‐lantern type diplatinum(II) complexes featuring the shortest Pt–Pt distances down to 2.80 Å is presented. The complexes exhibit efficient deep red phosphorescence from mixed metal–metal‐to‐ligand charge transfer and ligand‐to‐ligand charge transfer excited states. Organic light‐emitting diodes doped with this type of emitters show high efficiencies, small efficiency roll‐offs, and good operational stability.
Underwater wet-mateable connectors (WMCs) can be mated and de-mated in the subsea environment, which have been widely used in the ocean engineering. Since the high ocean pressure will cause a ...tremendous mate and de-mate force, the pressure-balanced oil-filled (PBOF) technology is introduced which can make WMCs operated at the depth of even 11,000 m. PBOF technology further gave birth to underwater pressure compensators (UPCs) which can reduce the mass of pressure housings used in autonomous underwater vehicles (AUVs) and can eliminate the influence of the ambient pressure on the hydraulic system of underwater robots. This paper aims to give a detailed investigation of PBOF technology and to develop a resilient bladder used in WMCs. First, the differential pressure equation of the bladder is derived. Second, an innovative finite element analysis (FEA) model involving fluid-solid interaction (FSI) is proposed to verify the theory by using ANSYS Mechanical and APDL co-simulation. Finally, a novel resilient bladder with a simple structure and low-cost is developed, and a prototype of UPC is manufactured to test the bladder's performance. This paper is the first report to publicly reveal the mechanism of PBOF technology in the aspects of theory, simulation and test, which provides the design methods for the application of PBOF technology.
•Pressure-balanced oil-filled (PBOF) technology is investigated in the aspects of theory, simulation and test.•The differential pressure equation is deduced and validated both by the proposed FEA model and the tests.•A novel resilient bladder used in wet-mateable connectors was developed, which has a simple structure and low-cost.•Using soft rubber can effectively reduce the differential pressure of bladders and can improve the bladder’s sensitivity.
Topological maps are favorable for their small storage compared to geometric maps. However, they are limited in relocalization and path planning capabilities. To solve the problem, a feature-based ...hybrid topological map (FHT-Map) is proposed along with a real-time map construction algorithm based on robot exploration. Specifically, the FHT-Map utilizes both RGB cameras and LiDAR information and consists of two types of nodes: main node and support node. Main nodes store visual information compressed by convolutional neural network and local laser scan data to enhance subsequent relocalization capability. Support nodes retain a minimal amount of data to ensure storage efficiency while facilitating path planning. After map construction through robot exploration, the FHT-Map can be used by other robots for relocalization and path planning. Simulation results demonstrate that the proposed FHT-Map can effectively improve relocalization and path planning capability compared with other topological maps. Moreover, simulations of the hybrid architecture are implemented to show the necessity of two types of nodes.
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