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Shale oil reservoirs exhibit ultralow permeability and complex pore structures, which result in non-Darcy low-velocity flow and cause permeability to be stress-sensitive. Moreover, two-phase flow of oil and gas frequently occurs during the depletion of shale oil reservoirs. Consequently, investigating the rate-transient behavior of shale oil wells necessitates comprehensive consideration of multiphase flow, threshold pressure gradients, and stress sensitivity. Although numerous analytical models exist for rate-transient analysis of multistage fractured horizontal wells, none of them simultaneously incorporate these critical factors. In this study, we extend the classical five-region model to incorporate multiphase flow, threshold pressure gradients, and stress sensitivity. The proposed model is solved using Pedrosa’s transformation, perturbation theory, the Laplace transform, and the Stehfest numerical inversion method. A systematic analysis of the influence of various parameters on the oil production rate and cumulative oil production is conducted, and a field case study is presented to validate the applicability and effectiveness of the model. It is found that the permeability modulus of the main fracture, the half-length of the main fracture, and the threshold pressure gradient of the unstimulated reservoir have a significant influence on cumulative oil production spanning 20 years. With a 100% relative input error, these parameters result in prediction errors of 23.77%, 16.65%, and 17.78%, respectively. In contrast, the threshold pressure gradient of the main fracture and the threshold pressure gradient of the stimulated reservoir have a negligible impact; under the same level of input error (100%), they cause only 0.36% and 0.48% prediction errors in the 20-year cumulative oil production period, respectively. This research provides an efficient and reliable framework for analyzing production data and forecasting shale oil well performance.

Objective To assess the diagnostic value of C-reactive protein (CRP) and procalcitonin (PCT) for anastomotic leakage (AL) following colorectal surgery. Methods We retrospectively analyzed data for patients who underwent colorectal surgery at our hospital between November 2019 and December 2023. CRP and PCT were measured postoperatively to compare patients with/without AL, and changes were compared between low- and high-risk groups. Receiver operating characteristic (ROC) curve analysis was used to assess the diagnostic accuracy of CRP and PCT to identify AL in high-risk patients. Results Mean CRP was 142.53 mg/L and 189.57 mg/L in the low- and high-risk groups, respectively, on postoperative day (POD)3. On POD2, mean PCT was 2.75 ng/mL and 8.16 ng/mL in low- and high-risk patients, respectively; values on POD3 were 3.53 ng/mL and 14.86 ng/mL, respectively. The areas under the curve (AUC) for CRP and PCT on POD3 were 0.71 and 0.78, respectively (CRP cut-off: 235.64 mg/L; sensitivity: 96%; specificity: 89.42% vs PCT cut-off: 3.94 ng/mL; sensitivity: 86%; specificity: 93.56%; AUC: 0.78). The AUC, sensitivity, and specificity for the combined diagnostic ability of CRP and PCT on POD3 were 0.92, 90%, and 100%, respectively (cut-off: 0.44). Conclusions Combining PCT and CRP on POD3 enhances the diagnostic accuracy for AL.

Nanoscale phenomena in kerogen pores could result in complicated non-Darcy effects in shale gas production, and so classical simulation approaches based on Darcy’s law may not be appropriate for simulating shale gas flow in shale. In general, understanding the shale gas transport mechanisms in a kerogen pore is the first and most important step for accurately simulating shale gas flow in shale. In this work, we present a novel lattice Boltzmann (LB) model, which can take account of the effects of surface diffusion, gas slippage, and adsorbed layer, to study shale gas flow in a kerogen pore under real gas conditions. With the Langmuir isothermal adsorption equation and the bounce-back/specular-reflection boundary condition, the gas–solid and gas–gas molecular interactions at the solid surface are incorporated into the LB model. Furthermore, the effects of surface diffusion and gas slippage on the free-gas velocity profile and mass flux in a kerogen pore are studied via the LB model. It is found that the free-gas velocity profile appears as a parabolic profile in a kerogen pore and the free-gas velocity at the center of the kerogen pore is apparently higher than that near the wall. In particular, we find that both surface diffusion and gas slippage can enhance the mass flux. Compared with gas slippage, surface diffusion is a more important factor on the shale gas transport in small pores, while it can be negligible in large pores.

Trichlorfon, an organophosphorus pesticide widely used in agriculture and other fields, poses a severe risk to both food safety and human health. We developed a photonic crystal film sensing platform for detecting trichlorfon, a hazardous organophosphorus pesticide. The method exploits trichlorfon’s inhibition of acetylcholinesterase (AChE). Normally, AChE catalyzes acetylcholine hydrolysis to produce acetic acid, which decomposes CaCO3 to release Ca2+. This triggers calcium alginate hydrogel formation, increasing solution viscosity and trapping water. When trichlorfon inhibits AChE, hydrogel formation fails, leaving the solution in a low-viscosity sol state with abundant free water. Immersing the film in trichlorfon-containing sodium alginate solutions causes water absorption and film swelling due to free water. Higher trichlorfon concentrations reduce hydrogel formation, increase free water, and amplify film swelling, resulting in proportionally higher reflectivity. The platform demonstrates a wide linear range (1–250 ng/mL) and a low detection limit (0.4 ng/mL) for trichlorfon. Successful analysis of real samples confirms its practicality for residue detection. This label-free thin-film sensor shows significant potential for monitoring trichlorfon and other organophosphorus pesticides.

Shale oil reservoirs are characterized by extremely low porosity and permeability, necessitating the utilization of multi-fractured horizontal wells (MFHWs) for their development. Additionally, the complex phase behavior and desorption effect of two-phase fluids make the fluid flow characteristics of shale oil reservoirs exceptionally intricate. However, there are no productivity models for MFHWs in shale oil reservoirs that incorporate the complex hydraulically fractured networks, the oil–gas desorption effect, and the phase change of oil and gas. In this study, we propose a novel productivity model for MFHWs in shale oil reservoirs that incorporates these complex factors. The conformal transformation, fractal theory, and pressure superposition principle are used to establish and solve the proposed model. The proposed model has been validated by comparing its predicted results with the field data and numerical simulation results. A detailed analysis is conducted on the factors that influence the productivity of shale oil wells. It is found that the phase behavior results in a significant 33% reduction in well productivity, while the fluid desorption leads to a significant 75% increase in well productivity. In summary, the proposed model has demonstrated promising practical applicability in predicting the productivity of MFHWs in shale oil reservoirs.

The structural integrity of pipeline girth welds is critical, especially when the welds involve heterogeneous materials and non-uniform wall thicknesses. Current evaluation methods that compare the strength of the weld to that of the base metal (BM) are inadequate for such complex welds. This paper addresses this gap by applying micro-tensile specimen testing to characteristic zones within heterogeneous girth welds that exhibit non-uniform wall thicknesses. We conducted tensile performance tests on X80 and X60 steel pipes featuring unequal wall thickness butt joints. The analysis focused on the wall thickness direction of the girth weld as well as the transverse direction, examining differences and patterns in performance across various regions. The findings provide an improved understanding of property gradients in heterogeneous girth welds and offer practical guidance for more reliable safety evaluation of pipelines with unequal wall thickness joints.

Climate change increases the risk of illness through rising temperature, severe precipitation and worst air pollution. This paper investigates how monthly excess mortality rate is associated with the increasing frequency and severity of extreme temperature in Canada during 2000-2020. The extreme associations were compared among four age groups across five sub-blocks of Canada based on the datasets of monthly T90 and T10, the two most representative indices of severe weather monitoring measures developed by the actuarial associations in Canada and US. We utilize a combined seasonal Auto-regressive Integrated Moving Average (ARIMA) and bivariate Peaks-Over-Threshold (POT) method to investigate the extreme association via the extreme tail index χ and Pickands dependence function plots. It turns out that it is likely (more than 10%) to occur with excess mortality if there are unusual low temperature with extreme intensity (all χ > 0.1 except Northeast Atlantic (NEA), Northern Plains (NPL) and Northwest Pacific (NWP) for age group 0-44), while extreme frequent high temperature seems not to affect health significantly (all χ ≤ 0.001 except NWP). Particular attention should be paid to NWP and Central Arctic (CAR) since population health therein is highly associated with both extreme frequent high and low temperatures (both χ = 0.3182 for all age groups). The revealed extreme dependence is expected to help stakeholders avoid significant ramifications with targeted health protection strategies from unexpected consequences of extreme weather events. The novel extremal dependence methodology is promisingly applied in further studies of the interplay between extreme meteorological exposures, social-economic factors and health outcomes.

With the growing global focus on reducing greenhouse gas emissions, hydrate-based CO 2 sequestration in marine sediments has gained wide attention due to its high storage capacity and thermodynamic stability of CO 2 hydrate. However, the limited understanding of the CO 2 hydrate stability zone, particularly in the presence of abundant swelling type clays, i.e., Na-montmorillonite, warrants further investigation. This study examines the thermodynamic effects of Na-montmorillonite on the phase equilibria of CO 2 hydrate under varying water contents (30–80 wt%). The results reveal that Na-montmorillonite inhibits CO 2 hydrate formation thermodynamically with a significant inhibition effect as the water content decreases. A notable leftward shift of up to 2.7 K in the phase equilibrium temperature was observed at 3.90 MPa with 30 wt% water content. A thermodynamic model was developed integrating the diffuse double layer theory and Hu-Lee-Sum water activity correlation model into the classical Chen-Guo model. The proposed model demonstrated high accuracy with the measured data with an absolute average deviation of pressure below 0.5%. The thermodynamic inhibition effect is attributed to the decrease in water activity caused by the Na + exchange in the diffuse double layer on the clay surface. This study also presents the implication of swelling type clay on the CO 2 hydrate stability zone in a permafrost setting, highlighting its impact on the CO 2 storage site selection and CO 2 storage capacity. These findings provide valuable insights for optimizing hydrate-based CO 2 sequestration strategies, contributing to CO 2 mitigation technology.

Background Oleanolic acid (OA), a pentacyclic triterpenoid abundantly present in various traditional Chinese herbs, exhibits promising anti-psoriatic potential owing to its broad pharmacological activities. Nevertheless, its clinical translation has been hindered by challenges including poor aqueous solubility, limited cutaneous permeation, and rapid systemic clearance, all of which compromise bioavailability when administered topically. To address these limitations, we designed and developed encapsulated and disulfide bonded OA-hyaluronic acid nanoprodrugs (OA-NPs@OA) for topical treatment of psoriasis in this study. Results OA-NPs@OA exhibited significantly enhanced cellular uptake via CD44 receptor-mediated endocytosis in keratinocytes, achieving a markedly lower IC 50 value compared to free OA and considerably stronger apoptosis induction effects. In the IMQ-induced murine model, topically applied OA-NPs@OA demonstrated superior transdermal penetration with sustained lesional retention, effectively reversing psoriatic phenotypes with remarkably reduced PASI scores and splenomegaly, normalized epidermal thickness, and suppressed immune inflammation and cytokines. OA-NPs@OA exhibited superior effects to free OA and Calcipotriol Ointment. Mechanistically, OA-NPs@OA concurrently suppressed keratinocyte hyperproliferation via blocking the YAP-AREG pathway axis and reduced immune cell infiltration by downregulating chemokine networks, breaking the psoriatic inflammatory loop. Crucially, OA-NPs@OA showed excellent biosafety with no dermal or systemic toxicity following consecutively topical administration. Conclusions OA-NPs@OA represents a novel targeted nanotherapy that overcomes the limitations of OA in anti-psoriasis by offering enhanced bioavailability, multimodal anti-psoriatic action, and optimized safety profiles. Graphical Abstract

Chinese cork oak ( Quercus variabilis ) is a widely distributed and highly valuable deciduous broadleaf tree from both ecological and economic perspectives. Seeds of this species are recalcitrant, i.e., sensitive to desiccation, which affects their storage and long-term preservation of germplasm. However, little is known about the underlying molecular mechanism of desiccation sensitivity of Q. variabilis seeds. In this study, the seeds were desiccated with silica gel for certain days as different treatments from 0 (Control) to 15 days (T15) with a gradient of 1 day. According to the seed germination percentage, four key stages (Control, T2, T4, and T11) were found. Then the transcriptomic profiles of these four stages were compared. A total of 4,405, 4,441, and 5,907 differentially expressed genes (DEGs) were identified in T2 vs. Control, T4 vs. Control, and T11 vs. Control, respectively. Among them, 2,219 DEGs were overlapped in the three comparison groups. Kyoto Encyclopedia of Genes and Genomes (KEGG) enrichment analysis showed that these DEGs were enriched into 124 pathways, such as “Plant hormone signal transduction” and “Glycerophospholipid metabolism”. DEGs related to hormone biosynthesis and signal transduction ( ZEP, YUC, PYR, ABI5, ERF1B , etc.), stress response proteins ( LEA D-29, HSP70 , etc.), and phospholipase D ( PLD1 ) were detected during desiccation. These genes and their interactions may determine the desiccation sensitivity of seeds. In addition, group specific DEGs were also identified in T2 vs. Control ( PP2C62, UNE12 , etc.), T4 vs. Control ( WRKY1-like, WAK10 , etc.), and T11 vs. Control ( IBH1, bZIP44 , etc.), respectively. Finally, a possible work model was proposed to show the molecular regulation mechanism of desiccation sensitivity in Q. variabilis seeds. This is the first report on the molecular regulation mechanism of desiccation sensitivity of Q. variabilis seeds using RNA-Seq. The findings could make a great contribution to seed storage and long-term conservation of recalcitrant seeds in the future.