Search Results (1,995)

Recent advancements in biology and medicine have facilitated the progress of nerve regeneration that markedly improves the treatment of peripheral nerve injuries, enhancing outcomes and recovery rates. It has been reported that erythropoietin (EPO) is currently being studied as a potential agent for neural repair. However, much evidence has confirmed that EPO treatment can induce systemic adverse effects in the clinical fields, including coronary stent thrombosis and deep vein thrombosis. Herein, a derivative of EPO without any hematopoietic activities, which is named carbamylated erythropoietin (CEPO), has been synthesized and investigated for its effects on peripheral neural repair both in vitro and in vivo. The in vitro experimental results demonstrated that CEPO enhanced Schwann cell viability, proliferation, migration, and nerve growth factor (NGF) expression, while the optimal concentration of CEPO was found to be 25 μg/mL. The in vivo observations at 21 days post-injection indicated that the CEPO group exhibited a significant functional improvement in the sciatic nerve injury model, guiding regrowing axons across the injury site. Thus, CEPO serves as a promising candidate or adjunctive strategy for peripheral nerve injuries, demonstrating promising clinical applications and potential for enhancing Schwann cell viability, proliferation, and migration, as well as anticipated nerve axon development. Full article

Subsurface freshwater in oceanic islands is typically shaped like a thin lens due to limited land area and recharge, often the primary freshwater source for local communities and highly vulnerable to seawater intrusion (SWI). Freshwater injection (FI) is considered as a feasible strategy for mitigating SWI in coastal aquifers. However, its transient effectiveness for freshwater lens (FWL) development and SWI mitigation in island aquifers and how the design parameters like FI depth, intensity, duration and injectant concentration affect its performance remain poorly understood. To address this, this study employs a two-dimensional, variable-density island groundwater model to simulate the transient responses of FWL development and SWI mitigation to various FI patterns. Five indicators are developed for comprehensive evaluation, including (1) freshwater recovery efficiency (FRE), and the relative changes in (2) average water table elevation (WTE), (3) FWL depth, (4) FWL volume, and (5) total aquifer salt mass. Results reveal FI universally raises average WTE, expands FWL dimensions, and promotes aquifer desalinization. Injection intensity is the primary driver of WTE rises and salt mass reduction, with higher intensities consistently yielding greater WTE rises and salt mass reductions. Deeper injection within the mixing zone increases FWL depth, but reduces the net gain in FWL volume. Moreover, early-stage FI is highly efficient for expanding FWL volume, often yielding FRE values above 100%, but FRE converges toward zero over time as the system moves toward a new hydrodynamic equilibrium, returning diminishing marginal benefits for long-term FI. Full article

The physicochemical mechanisms and numerical characterization of amine-ether gemini surfactant emulsion flooding remain insufficient, limiting its field application in low-permeability reservoirs. This study developed a refined numerical simulation method that integrates full-process emulsion kinetics, including generation, coalescence, dispersion-assisted oil displacement, and demulsification, with graded emulsion characterization using the differentiated inaccessible pore volume (IPV) and residual resistance factor (RRF). Core-flooding validation demonstrated that the model accurately reproduced the key dynamic responses of water cut reduction and oil production increase, with a relative error of about 3.0%. Mechanistic analysis showed that the enhanced oil recovery performance arose from the combined effects of ultralow interfacial tension and emulsion-induced profile control. Relative to conventional surfactant flooding, emulsion flooding increased oil recovery by an additional 4.8–5.0% and lowered water cut by about 12 percentage points. For the Shengli Oilfield pilot block, the optimized injection design involved a surfactant concentration of 1.2 wt.%, an injection rate of 60 m³/d, a slug size of 0.01 PV, an injection–production ratio of 0.95, and a stepwise concentration-decline strategy. The field pilot further confirmed the applicability of the method: daily oil production of the well group increased by 46.5%, while comprehensive water cut decreased by 8.6 percentage points. These results demonstrate the value of the proposed method for both mechanistic characterization and field design of amine-ether gemini surfactant emulsion flooding in heterogeneous low-permeability reservoirs. Full article

The current lack of effective treatments for traumatic spinal cord injury (SCI) presents a significant challenge in managing the complex microenvironmental alterations that follow the initial trauma. This study developed an injectable alginate hydrogel dynamically cross-linked by tannic acid–zinc nanoparticles (TA@Zn NPs), which exerts neuroprotective effects through the sustained release of zinc ions (Zn²⁺) and antioxidant TA@Zn NPs. TA@Zn NPs were cross-linked with phenylboronic acid-modified sodium alginate (SA) to form an injectable gel system. In response to the acidic and ROS-rich microenvironment characteristic of SCI, the hydrogel undergoes degradation, thereby triggering the disintegration of TA@Zn NPs and the concomitant release of Zn²⁺, enabling sustained therapeutic delivery. In a rat model of contusion injury, the degradation of TA@Zn NPs and the sustained release of Zn²⁺ significantly reduced oxidative damage and promoted axonal regeneration, which in turn inhibited scar formation and enhanced the tissue’s antioxidant capacity. Consequently, the group treated with the Zn²⁺-releasing hydrogel exhibited significant recovery of motor function. Collectively, these results validate the dual-function integration of Zn²⁺ as a dynamic cross-linker and neuroprotective agent within injectable hydrogels as a robust strategy for SCI repair, presenting a clinically translatable paradigm for neural regeneration. Full article

Nanobubbles (NBs) are emerging as a promising area of research across multiple scientific and industrial domains due to their unique physicochemical characteristics. NBs exhibit distinctive properties compared to normal bubbles, including high internal pressure, a large specific surface area, high interfacial activity, and long-term stability in liquids. Therefore, NBs have gained increasing attention as a novel enhanced oil recovery (EOR) technique, offering potential advantages over traditional gas flooding and chemical flooding. CO₂-NB specifically represents a particularly promising approach as an intersection of EOR and carbon capture, utilization, and storage (CCUS), as CO₂-NB enables hydrocarbon recovery and in situ CO₂ utilization and storage at reservoir conditions. This paper presents a structured comparative discussion of currently identified experimental EOR studies that employ CO₂-NBs. Based on the observations of these experiments, this paper discusses the proposed mechanisms in those experiments or other studies that could scientifically play a role in achieving incremental recovery. The main mechanisms discussed include interfacial tension reduction, wettability alteration, CO₂ transfer from NBs into the oil liquid phase, and suppression of gravity segregation. Other possible contributors discussed in the literature include buoyancy-assisted mobilization, induced shock waves, and drag force reduction. These mechanisms are examined in relation to the distinctive properties of CO₂-NBs, showing how these properties contribute to the occurrence of the proposed mechanisms, showcasing the potential of CO₂-NBs as an emergent EOR–CCUS technology. A preliminary probabilistic assessment was performed to estimate CO₂ storage potential during CO₂-NBs EOR injection. The results suggest that the majority of the injected CO₂ is dissolved in the saturated liquid phase, while the amount of free NBs is negligible, indicating that CO₂-NB injection may provide secure storage through solubility trapping, but with lower storage capacity compared to conventional geological sequestration in saline aquifers. Full article

Copper is a common pollutant in aquatic environments. Excess copper in water can enter aquatic organisms through respiration, feeding, and adsorption, thereby exerting serious adverse effects on their health. In this study, NEW Genetically Improved Farmed (GIFT) Nile tilapia (Oreochromis niloticus L.) was used to explore the effect of copper on the hepatopancreas and post-exposure recovery. Acute exposure was simulated via an intraperitoneal injection of 3.75 mg Cu²⁺/kg body mass, while physiological saline injections served as the control. Samples were collected on days 1, 7, 14, and 21 post-exposure to evaluate growth performance, histopathological changes, antioxidant enzyme activities, and the expression of oxidative stress-related genes in the hepatopancreas. The results show that body length and mass increased within 21 days of the injection and copper exposure did not significantly affect fish growth. On day 1 after copper injection, numerous vacuoles appeared in hepatopancreatic tissues. On day 14, congestion and obvious hepatic sinusoids were observed. However, on day 21, the tissue structure showed gradually recovery. Compared to the control group, superoxide dismutase (SOD) activity was significantly higher in the exposed group on days 1, 14, and 21, and SOD gene expression was significantly elevated on day 21. Catalase (CAT) activity was significantly higher on day 7, and the expression of the CAT gene increased significantly on days 1 and 21. Glutathione peroxidase (GSH-Px) activity decreased significantly on day 7, whereas GPX gene expression increased significantly at the same time point. No significant difference in acetylcholinesterase (AChE) activity was observed during the experiment. In conclusion, copper administered via intraperitoneal injections induced significant activation of the antioxidant defense system and histopathological damage in the hepatopancreas of tilapia. Although tissue damage gradually recovered over time, the activation of the antioxidant defense system partially persisted. Ultimately, copper exposure did not significantly affect growth indicators such as body length and mass. These results advance our understanding of copper toxicity in farmed fish and provide a scientific reference for safe aquaculture production. Full article

Peripheral nerve injuries cause profound medical and socioeconomic consequences. Despite substantial microsurgical advances, including nerve autografting, nerve transfers, and the commercial availability of effective conduits, functional recovery remains incomplete for most patients. Current outcomes underscore the need for novel adjunctive therapies capable of enhancing axonal regeneration, accelerating reinnervation, and mitigating denervation-induced target atrophy. Tacrolimus, a calcineurin inhibitor widely used in organ transplantation, has emerged as a potent immunomodulatory and neuroregenerative agent. However, its systemic use is constrained by severe dose-limiting toxicities and metabolic derangements. This limitation has driven a paradigm shift toward localized tacrolimus delivery, leveraging biomaterials to achieve therapeutic drug concentrations at the repair site while minimizing systemic toxicity. This review synthesizes the state-of-the-art advances in biomaterial-based tacrolimus local delivery systems. We highlight biological mechanisms underlying tacrolimus-mediated neuroregeneration and immunomodulation. Engineering strategies including nerve conduits, wraps, injectable hydrogels, electrospun scaffolds, and stimuli-responsive carriers are discussed, with attention to polymeric composition, fabrication technologies, degradation kinetics, and pharmacological performance. We also explored the regulatory, manufacturing, and scalability challenges inherent to drug–device combination products. Finally, we identify emerging directions including multimodal biomaterials that integrate tacrolimus with trophic factors, extracellular vesicles, or bioelectrical stimulation. Collectively, biomaterial-enabled tacrolimus delivery represents a transformative strategy to bridge traditional nerve surgical repair and functional recovery. This review provides a roadmap for future interdisciplinary innovation at the interface of biomaterials science, neurobiology, pharmacology, and surgery. Full article

Low-permeability reservoirs at the high-water-cut stage commonly suffer from dominant water channel development, poor sweep of weakly connected zones, and inefficient mobilization of remaining oil. Existing profile control or oil displacement agents can improve either flow diversion or microscopic oil displacement, but their single-agent evaluation does not fully explain the coupled process of sweep expansion and remaining oil mobilization. To address this issue, this study focuses on a previously optimized HK-0417/ALT-603 composite system and investigates its synergistic behavior at pore, core, and well group scales. Microscopic visualization displacement experiments were used to identify streamline redistribution and remaining oil evolution. Natural core experiments were conducted to evaluate injectivity adaptability and plugging persistence. Under slug injection conditions, the Box–Behnken design was employed to optimize the injection parameters. Finally, the field pilot response was analyzed based on production data from test wells in the Changqing Oilfield. The results show that the combination system simultaneously achieves streamline expansion and residual oil reduction: the injected fluid is redistributed toward weakly swept zones, large continuous oil bodies are fragmented and dispersed, and both sweep efficiency and oil displacement efficiency are superior to those of individual agents. Natural core experiments indicate that the injection pressure difference is generally controllable in cores with permeabilities ranging from 1.76 to 7.02 mD, and the plugging rate during subsequent water flooding reaches 75.47–80.54%. Response surface optimization yields the following optimal parameter combination: profile control slug volume = 0.41 pore volume (PV), oil displacement slug volume = 0.61 PV, injection rate = 0.19 mL/min, with a corresponding predicted enhanced oil recovery (EOR) of 18.52%. In the field pilot, the cumulative injection volumes of the two injectors are 41,898 kg and 61,472 kg, respectively. The injection pressure in the well group increases from 5.8 MPa to 7.0 MPa, the comprehensive water cut decreases from 90.6% to 85.3%, and the monthly decline rate is reduced from 0.5% to 0.2%. The proposed system mainly acts by increasing flow resistance and redirecting flow in high-water-cut channels, while it enhances oil detachment through interfacial tension reduction in oil-bearing pores. After optimizing the slug parameters, the field pilot exhibits a clear phased response and promising application potential. Full article

The objective of this study was to evaluate the effects of timing of injectable trace mineral (ITM) administration (28 days (d) prior to or at weaning) on performance and health in mixed-sex beef calves (n = 115; 224 ± 40 kg). Calves were randomly assigned to one of the following treatments: (1) no ITM (CON), (2) ITM administered 28 d before weaning (PW), or (3) ITM administration at weaning (WEAN). At weaning, calves were transported to a local auction barn, held overnight, and returned the following day; BW, blood, and hair samples were collected prior to and through the receiving period. Data were analyzed using SAS 9.4. Serum Se increased in PW calves following ITM administration (p < 0.01). Serum Mn increased in PW and WEAN groups (p < 0.01) and PW calves showed increased serum Cu at weaning (p < 0.01). Across treatments, calves experienced 6% shrink following weaning and transport, with recovery of BW and intake occurring within 21 d and 8 d, respectively. Despite improved mineral status, no performance benefits were observed during the receiving period, reflecting adequate baseline mineral status and low-stress management conditions, suggesting that ITMs may have limited benefits in well-managed herds. Full article

The water huff-n-puff imbibition oil recovery technique has been recognized as an important approach to supplementing formation energy and recovering the remaining oil, attracting increasing attention. To further improve imbibition efficiency, a surfactant-aided huff-n-puff imbibition technique under high pressure was proposed. However, the imbibition mechanisms under high pressure, particularly under variable pressurization modes, remain insufficiently understood. In this study, the effects of different pressurization methods (constant vs. variable pressure) and surfactant types on imbibition behavior were systematically investigated. The results show that, compared with spontaneous imbibition, high-pressure imbibition increases oil recovery by 7–10% and the imbibition rate by 1–2 times, with the variable pressurization mode demonstrating a more pronounced enhancement. Surfactant selection should not pursue ultra-low interfacial tension (IFT) alone; instead, the wettability alteration ability is more critical. An optimal IFT–wettability synergy window is identified, through which the best imbibition performance is achieved when the IFT ranges from 10⁻² to 10⁻¹ mN/m and the contact angle ranges from 30° to 60°. Furthermore, the slug injection mode provides a synergistic effect with high-pressure variable pressurization and surfactant action. Compared with high-pressure formation water imbibition, surfactant-aided imbibition increases oil recovery by 10.44% and the imbibition rate by three times. These findings provide a deeper understanding of the key factors governing imbibition behavior and support the application of surfactant-aided huff-n-puff imbibition under high pressure in tight sandstone reservoirs. Full article

Reverse osmosis (RO) membranes are widely applied in reuse facilities, but the management of RO concentrate remains a major sustainability challenge. Conventional brine disposal methods, such as deep well injection or evaporation ponds, are costly, energy intensive, and often ineffective at addressing the accumulation of contaminants of emerging concern (CEC) and per- and polyfluoroalkyl substances (PFAS). Bioelectrochemical systems, such as microbial fuel cells (MFCs), offer a promising pathway for sustainable brine organic load management by simultaneously reducing organic load and recovering energy. In this study, a pilot-scale MFC system (Aquacycl BETT^®, Escondido, CA, USA, unit, 12 modular reactors) was evaluated for treatment of RO concentrate produced by a combined ultrafiltration and closed-circuit reverse osmosis pilot train at the San Jacinto Valley Regional Water Reclamation Facility (San Jacinto, CA, USA). Operating with a 4-h hydraulic retention time, the MFC achieved an average chemical oxygen demand (COD) removal of 40% and biochemical oxygen demand (BOD₅) removal of 52%. Coulombic efficiency ranged from 2.8% to 15.5%, with an average energy recovery value of about 8.1 Wh per kg of COD removed. PFOS concentrations decreased by 36% across the MFC, and PFAS were not detected in the harvested anode biomass. The mechanism of PFOS attenuation (e.g., adsorption vs. transformation) was not directly evaluated. These findings highlight the potential of MFCs as a bioelectrochemical solution for sustainable water reuse RO brine management. Full article

As a key driver of the rural revitalization strategy, the uneven development of rural tourism urgently requires resolution. To break through the limitations of traditional rural tourism research that focuses on a single economic dimension, this study innovatively constructs a comprehensive analytical framework integrating multi-dimensional evaluation, coupling measurement, and factor identification to examine the interaction between rural tourism development and ecosystem recovery capacity. Taking the Yangtze River Delta region of China as an empirical case, this paper analyzes the spatial coupling relationship and its associated factors between rural tourism development capacity and ecosystem recovery capacity. The results reveal that: (1) At the socio-economic level, the development of rural tourism in the Yangtze River Delta presents a spatial differentiation, with the southeastern region performing significantly better than the northwestern region, and 60.46% of the areas reaching a moderate level or above; (2) At the ecosystem level, high-value areas of ecosystem recovery capacity (50.28%) are mainly concentrated in the southern part; (3) The overall regional coordination level is relatively low, with 13 regions in the coordination stage (accounting for 35.3% of the total spatial area); (4) Technology and financial investment are the dominant factors associated with the coupling coordination degree, indicating a spatial pattern characterized by “innovation-driven” rather than “resource dependence”. Relying solely on natural background conditions is insufficient to build core advantages; we hypothesize that external interventions such as “capital injection” and “technological support” may serve as potential pathways to improve coordination and facilitate ecological value realization. The findings not only provide a new paradigm for evaluating the development quality of rural tourism, but also establish a complete research chain of “diagnosis-classification-optimization,” providing a scientific basis for formulating regionally differentiated development strategies. This study holds significant theoretical value and practical guiding significance for promoting the sustainable development of rural tourism. Full article

Vertical land motion in urban areas is a critical manifestation of groundwater, directly affecting infrastructure stability and groundwater sustainability. While land subsidence caused by groundwater extraction has been widely investigated, the opposite process—surface uplift induced by groundwater recovery—remains poorly documented or understood, particularly regarding its hydrological mechanisms and potential hazards. Here, we integrate InSAR time-series analysis of Sentinel-1 imagery (2017–2025) with groundwater well records to quantify the spatial–temporal characteristics of uplift in Xi’an, China, and to evaluate its hydrogeological drivers. Results reveal a persistent surface uplift zone south of the ancient city in Xi’an, with rates up to 20 mm/yr. The uplift correlates closely with rising groundwater levels in the shallow confined aquifer, indicating a strong coupling between aquifer recharge and surface uplift. Calculated storage coefficients and hydraulic diffusivity values highlight marked spatial variations, constrained by some ground fissures that act as both mechanical discontinuities and hydrological barriers controlling pressure diffusion. Time-series analysis further identifies the eastward propagation of subsidence-to-uplift reversal in Yuhuazhai, an urban village with groundwater injection, which is used to quantify the diffusivity coefficients. Field investigations show that rapid groundwater rebound can lead to uplift-related hazards, such as basement seepage, underscoring that surface uplift must be considered alongside subsidence in urban water management. Full article

The capacitance resistance model (CRM) is an analytical tool widely used to forecast reservoir performance in enhanced oil recovery (EOR) methods. By representing flow dynamics and the connectivity between injection and production wells through the parameter of interwell connectivity, CRM offers fast computational processing and minimal input data requirements. These advantages make CRM a practical alternative for rapid reservoir analysis, especially when full-scale numerical simulations are infeasible due to time and budget constraints. CRM, rooted in material balance and productivity equations, uses injection/production rates and bottom-hole pressure data to construct reservoir models through optimization techniques, which can then be combined with oil fractional flow models for predictive purposes. Initially designed for waterflooding operations, CRM has seen limited but promising applications in gas injection projects, where research remains incomplete. This study presents a new formulation of CRM tailored for immiscible gas injection, incorporating the pseudo-pressure concept coupled with a saturation profile. The pseudo-pressure concept is a mathematical transformation that linearizes gas flow equations by accounting for variations in gas compressibility and viscosity with pressure. The proposed CRM was evaluated using a PUNQ-S3 benchmark reservoir model in the CMG IMEX black oil simulator, involving two injectors and four producers. History- matching results for fluid production rates showed that the newly developed CRM achieved the lowest NRMSE, outperforming other CRM models across a wide range of reservoir properties. Sensitivity analyses were conducted to examine the effects of gas and oil PVT properties on the model’s performance. The newly developed CRM, incorporating the pseudo-pressure concept and saturation profiles, demonstrates superior performance in predicting fluid production rates, achieving an average NRMSE of 15.3% in a base case scenario, compared to other tested CRM models. Additionally, the sensitivity analysis on the effect of fluid properties shows that higher gas viscosity, lower gas formation volume factor, and increasing oil API gravity improve the CRM model’s performance, and under all tested conditions the newly developed CRM provides the most accurate production history match. This study not only establishes the new CRM as a robust and accurate predictive tool for immiscible gas injection but also provides a comprehensive discussion on reservoir parameter ranges and model limitations, advancing the applicability of CRM in EOR processes. Full article