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Carbonate reservoirs contribute the highest proportion of natural gas production around the world, and commingled production is frequently used to increase production for the multilayer reservoirs. However, the complex pore structure including pore, fracture and cavity, and the presence of edge/bottom water increase the difficulties in evaluation its commingled production performances. In this work, three comingled patterns of digital rocks are reconstructed based on the CT scanning images, and the lattice Boltzmann method is used to investigate the commingled production with water invasion. The results show that the fracture and cavity commingled production pattern has the largest interlayer heterogeneity, and the production ratio between the two layers can reach 6.7. Commingled production for the system with different interlayer pressure may lead to backflow phenomenon. Especially, if the interlayer heterogeneity is large and the initial pressure of the low-permeability layer is lower, the backflow volume would be very large. The water invasion during commingled production can influence the flow capacity of the other gas layers even there is no pressure interference. In addition, if the water-invaded layer has larger pressure, the produced water will continuously flows backs to the gas layer until the pressure of the two layers becomes balanced. The coupled effects of pressure interference and water invasion significantly damage the commingled-production performance. This work revealed the gas-water two-phase flow behaviors during commingled production, which provide fundamental support for the scientific development of multilayer carbonated reservoir.

An optical Airy channel is built in a paraelectric Mn: KLTN crystal via a photo-induced Airy beam based on the photo-refractive effect. A laser beam, incident with the main lobe of the Airy channel, propagates along the Airy channel with a bias field as the control parameter. We find that the light beam is nicely confined in the Airy channel and propagates along it, presenting Airy-like properties of non-diffraction and bending action under a certain voltage range; then a breathing soliton can be formed with bias electric field rising, originating from space-charge-field-induced nonlocal refractive index perturbation. The experiment is corroborated by simulation. This Letter opens up new possibilities for fabricating an electrical engineering functional device, such as optical routing.

Purpose: To describe and interpret secular time trends in gallbladder cancer (GBC) incidence, mortality, and diagnostic approach using 37 years of cancer registry data in urban Shanghai.Methods: Data on registration of GBC in urban Shanghai during 1973 and 2009 were collected by the Shanghai Cancer Registry. To describe time trends and to identify specific time points when significant changes occurred, we used joinpoint regression analysis.Results: The age-standardized rates (ASRs) of incidence increased from 1.1/100,000 (1973–1975) to 2.9/100,000 (2006–2009) in men and from 1.7/100,000 (1973–1975) to 3.9/100,000 (2006–2009) in women. ASRs of incidence increased significantly with estimated annual percent changes (EAPCs) of 2.8% in men and 2.5% in women. The mortality trends increased significantly, with EAPCs of 2.8% in men and 2.5% in women. The increasing incidence and mortality rates were primarily observed in men ⩾60 years of age and in women ⩾70 years of age. Notable downward trends in incidence and mortality were identified among women age 60–69 years over the last decade. The percentage of GBC diagnosed by pathology increased steadily over the years while the percentage of GBC diagnosed by imaging, surgery, and biochemistry sharply increased from 1987 onwards.Conclusions: Thirty-seven years of cancer registry data document a tremendous increase in incidence/mortality and a slight decline in incidence/mortality over the last decades for GBC, especially among women, in Shanghai. The development of diagnostic approaches and aging population may play important roles.

Precious metal nanostructures have attracted considerable attention for their unique optical properties. In this paper, a bilayer ring structure which realizes dual-band/three-band band-stop filters in the near-infrared range is designed. It has been verified with numerical simulation, by altering the radius of the two rings, the filter wavelength can be adjusted, during which efficiency of the filter (98%) is always achieved. Further investigation reveals that the filter effect is attributed to the synergistic effect with the absorption caused by the ohmic heat and the scattering by the resonance radiation, which is applicable to linearly polarized light and circularly polarized light simultaneously, promising potential applications in sensing and solar cells.

During the development of carbonate reservoirs, the risk of bottom water invasion is a frequent concern. Pore-scale simulation methods are commonly acknowledged as effective tools for investigating the dynamics involved in water invasion mechanisms. Despite extensive research on gas-water two-phase flow, few studies have investigated reservoirs with interlayers, which can remarkably affect assessments of water invasion. Three models were designed to study the effects of different interlayer distributions on flow behavior. A mathematical model based on the volume of fluid (VOF) method was employed to describe variations in water saturation. The four primary influencing factors (interlayer distribution, gravity, pressure difference, and wettability) were studied based on simulations. The accuracy of the model was validated through comparisons with microfluidic visualization experiments. Compared to the model without interlayers, the models with semi-permeable and semi-sealed interlayers reduced the risk of water invasion, resulting in slower upward water saturation rates and delayed water breakthrough times. Neglecting gravity would introduce errors of up to 5.6% in water saturation and 24.2% in water breakthrough time for the models with interlayers. Controlling the pressure difference within 1.5 MPa/100 m would effectively reduce the produced water-gas ratio and delay the water breakthrough time. The water invasion behavior in the models with interlayers was highly sensitive to contact angles in the range of 50°–60°, while its effect on the model without interlayers was relatively small. Field-scale water invasion dynamics with examples from the Yuanba (YB) gas field in the Sichuan Basin, China, were consistent with the pore-scale simulation results. This work provides fundamental support for and valuable insights into the development of similar gas reservoirs, offering a strong foundation for future endeavors in this field.

The broadband circular polarizer based on the surface plasmon of a metal nanostructure has important practical application due to its adjustability, low cost, and easy integration. In this article, a twisted multilayer double semi-disc structure is designed to allow for a broadband circular polarizer, whose transmission spectra are simulated using the finite element method under left-handed circularly polarized and right-handed circularly polarized extinction. The results show a large extinction ratio up to 900 for properly designed geometry and a broad bandwidth (defined as extinction ratio >10) of 50–160 nm. Additionally, the broadband position, bandwidth, and extinction rate are all sensitive to some geometric parameters, such as rotation angle, disk radius, and more, and the mechanism of this phenomenon is clarified by exploring the plasmon electromagnetic resonance on nanostructures.

Circular polarizers have potential applications in optical communication and liquid crystal display. In this paper, a multilayer twisted nanoring-rod nanostructure is designed. The finite element method is used to explore the surface plasmon of the structure under the excitation of left-handed circularly polarized light and right-handed circularly polarized light. The results show that the structure can be used as a polarizer in the tunable operating bandwidth of 400–1290 nm, and tunability is achieved by changing the filling medium near the structure instead of the geometric parameters of the nanostructures. We qualitatively reveal the physical mechanism of this phenomenon from the perspective of plasmon resonance coupling by plotting the charge distribution at several specific wavelengths.

A chiral nanostructure array is designed, which is composed of a bilayer rotational F4-shaped nanoarray configuration. The surface plasmon resonance and circular dichroism are studied by changing the parameters of the structure. The results show that the structure has strong multiband circular dichroism, which is attributed to the coupling of the layers. In theory, based on the Born–Kuhn model, the upper and lower nanostructures are equivalent to electric dipoles. By analyzing the coupling mode of electric dipoles in the upper and lower layer, the mechanism of circular dichroism and the shift of the circular dichroism resonance are revealed. Besides, there are several specific modes that are fault tolerant of fabrication issues. This feature unveils the bright prospect of spectral anti-interference. So, the suggested chiral nanostructure can be used in biologically targeted molecular detection and spectral sensing.

The optical chirality of a bilayer twisted tetramer nanostructure is investigated theoretically. The difference of transmission spectra under left- and right-handed circularly polarized extinction produces very large optical chirality of 91% due to the different plasmonic hybridization patterns between the nanorods. This structure also allows the generation of a perfectly right/left-handed system at certain modes, because this mode nearly vanishes under the illumination of the left/right-handed light. Moreover, tunable optical chirality is achieved, which is also found to be easily affected by geometric parameters such as the separation distance between the two layers, the length of the nanorod, and the arrangement of nanorods. We consider the charge vibrations of four nanorods at the same layer as an equivalent dipole and explain the dependence of the circular dichroic spectrum on the geometric parameters. This work suggests that the bilayer twisted tetramer nanostructure can be considered a potential candidate for achieving large optical chirality, applicable to the fields of polarization polarizer fabrication and biological detection.

The spatial anisotropy of Au nanorod results in two distinct orientational modes by which the polarization orientation dependence of excitation and emission can be studied. In this work, a periodical distributed metallic nanostructure substrate, which contains an array of Au nanorods, is synthesized, and the polarization dependence of the plasmon enhanced fluorescence effect is investigated experimentally and numerically. It is found that the fluorescence emission enhancement of organic probe fluorophores located at the surface of Au nanorods depends on the polarization angle very sensitively. Different polarization orientations of the excitation light result in very different enhancement effects. As a result, the change of the polarization orientation of the excitation light can be a sensitive marker of surface chemistry and other possible practical applications.

A single silica-shell isolated Au-Ag alloy nanoparticle is used for investigating a metal-enhanced fluorescence effect. Well-dispersed alloy nanoparticles are prepared by the facile chemical method, and the property of local surface plasmon resonance is controlled by adjusting the metal component of the alloy and shell thickness. The distance dependence of fluorescence enhancement for a single Au-Ag alloy nanoparticle is studied systematically with different silica shell thickness ranging from 2 to 35 nm. The isolation shell not only adjusts the distance between metal surface and fluorophore emitters but also improves the chemical stability of the metal particle.

Sea salts act as an important medium for atmospheric processing. One intensive field campaign in the September–October period of 2019 was conducted at a subtropical coastal site over the South China Sea. Unexpected high concentrations of acidic gaseous precursors were observed, yielding high sulfate in PM2.5. Na+ranked as the third highest inorganic species, about half of NH4+. Significant cation deficiency was found due to the ammonia‐poor environment. Diel patterns of most air pollutants from land breeze were stronger than that from marine breeze and presented pronounced unimodal distributions, which were ascribed to complex chemical processing mixed with regional transport. Thermodynamic equilibrium model (ISORROPIA II) simulation revealed sea salts could be internally mixed with fine particle secondary species and suggested evident multiphase reactions on sea salts. The simulated aerosol pH reached as low as 1.63 ± 0.50, which was related to high sulfate, insufficient alkaline species, and low aerosol liquid water content. During a continuous sea breeze episode, SO42−was underpredicted by 2.89 ± 3.85 μg m−3if Na+was not considered in ISORROPIA simulation. The retrieved Na+‐related ion pairs (NaCl, NaHSO4, and Na2SO4) accounted for about one‐fourth of the total inorganic aerosols. This study highlighted that intense atmospheric processing on sea salts occurred in fine particles and the mixing state between sea salts and other aerosol species should be considered in aerosol acidity prediction and secondary aerosol formation in coastal regions. Sea salts were internally mixed with the secondary species even in fine particle, suggesting evident multiphase reactions on sea saltsAerosol pH was very low at the land‐sea interface and it depended on the relative strengths of sea salts versus terrestrial ammonia emissionsThe retrieved chemical forms of SO42−contained a substantial contribution from bisulfate, mainly in the form of NaHSO4and NH4HSO4 Sea salts were internally mixed with the secondary species even in fine particle, suggesting evident multiphase reactions on sea salts Aerosol pH was very low at the land‐sea interface and it depended on the relative strengths of sea salts versus terrestrial ammonia emissions The retrieved chemical forms of SO42−contained a substantial contribution from bisulfate, mainly in the form of NaHSO4and NH4HSO4

Dipeptidyl peptidase IV inhibitors are a new class of antidiabetic drugs. It is urgent, therefore, to fully understand the pharmacology of these inhibitors. Although dipeptidyl peptidase IV metabolizes at least 24 endogenous substrates, the pharmacological consequences of inhibiting the metabolism of most of these substrates is unknown. Our previous results show that Y(1) receptors, but not Y(2) receptors, enhance renovascular responses to angiotensin II in kidneys from genetically susceptible animals (spontaneously hypertensive rats). Dipeptidyl peptidase IV converts peptide YY(1-36) (circulating hormone) to peptide YY(3-36), and peptide YY(1-36) is a Y(1)-receptor agonist, whereas peptide YY(3-36) is a selective Y(2)-receptor agonist. Therefore, it is conceivable that inhibition of dipeptidyl peptidase IV in genetically susceptible kidneys may increase the ability of peptide YY(1-36) to potentiate angiotensin II-induced renal vasoconstriction. Here we demonstrate that in kidneys from spontaneously hypertensive rats 1) peptide YY(1-36) potentiates renovascular responses to angiotensin II, whereas peptide YY(3-36) has little effect, 2) 3-N-[(2S,3S)-2-amino-3-methylpentanoyl]-1,3-thiazolidine (P32/98) (dipeptidyl peptidase IV inhibitor) augments the ability of peptide YY(1-36) to enhance renovascular responses to angiotensin II, 3) dipeptidyl peptidase IV is expressed in preglomerular microvessels and glomeruli, 4) kidneys metabolize arterial PYY(1-36) to PYY(3-36) via a mechanism blocked by P32/98, and 5) preglomerular microvessels and glomeruli convert peptide YY(1-36) to peptide YY(3-36), and this conversion is inhibited by P32/98. We conclude that dipeptidyl peptidase IV is expressed in the renal microcirculation and inhibition of this ecto-enzyme causes arterial PYY(1-36) to more effectively enhance angiotensin II-induced renal vasoconstriction in genetically susceptible kidneys.

The "extracellular cAMP-adenosine pathway" refers to the conversion of cAMP to AMP by ecto-phosphodiesterase, followed by metabolism of AMP to adenosine by ecto-5'-nucleotidase, with all the steps occurring in the extracellular compartment. This study investigated whether the extracellular cAMP-adenosine pathway exists in proximal tubules. Freshly isolated proximal tubules rapidly converted basolaterally administered cAMP to AMP and adenosine. Proximal tubular cells in culture (first passage) rapidly converted apically administered cAMP to AMP and adenosine. In both freshly isolated proximal tubules and cultured proximal tubular cells, conversion of cAMP to AMP and adenosine was affected by a broad-spectrum phosphodiesterase inhibitor (3-isobutyl-1-methylxanthine), an ecto-phosphodiesterase inhibitor (1,3-dipropyl-8-p-sulfophenylxanthine), and a blocker of ecto-5'-nucleotidase (alpha,beta-methyleneadenosine-5'-diphosphate) in a manner consistent with exogenous cAMP being processed by the extracellular cAMP-adenosine pathway. In cultured proximal tubular cells, but not freshly isolated proximal tubules, stimulation of adenylyl cyclase increased extracellular concentrations of cAMP, AMP, and adenosine plus inosine, and these changes were also modulated by the inhibitors in a manner consistent with the extracellular cAMP-adenosine pathway. Conversion of renal interstitial (basolateral) cAMP and AMP to adenosine in vivo was shown by microdialysis coupled with ion trap mass spectrometry. Western blot analysis showed A(1), A(2A), and A(3) receptors on both apical and basolateral proximal tubular membranes, with A(1) and A(2A) receptors more highly expressed on basolateral compared with apical membranes. We conclude that cAMP that reaches either the apical or basolateral membranes of proximal tubular cells is converted in part to adenosine that has ready access to adenosine receptors.

SummaryThe functional gene for human recombination signal sequence-binding protein (RBP-Jk) and corresponding processed psudogenes have been isolated from various species, such as Drosophila, Xenopus, mouse, and human. Here we report the isolation of another two genomic pseudogenes of human RBP-Jk, named K2 and K7, from a cosmid library of Hela cells. The nucleotide sequences of both genes exhibited more than 95% homology to the functional human gene for RBP-Jk. Moreover, they did not contain any intron sequences and were interrupted by several stop codons in all frames. In situ hybridization demonstrated that the pseudogenes, K2 and K7, were localized at chromosomes 9p13 and 9q13, respectively. Their physical maps differed from those of the true functional gene and of the pseudogenes reported previously by Amakawa et al. (1993).