bluuebunny/crossref_metadata_2025 huggingface dataset:
Feasibility of Near Miscible Flooding By Production Gas Rejection with Varying CO2 Content in Qinhuangdao Oilfield
Authors: Chen Hao , Zhang Xiansong , Li Baozhen , Mei Yuan , Tang He , Wang Shuai
Published: August 2017

A newly discovered offshore oilfield in QHD 29-2 block is facing the problem of selecting the appropriate developing method. It covers approximately 2300 km2 and with an average water depth of 27.6m. The depth of the exploration well is over 3600 m with thick sand layer and oil zone. Conventional waterflood cannot be implemented due to the reservoir characteristics of small pores and throats, complex lithology, strong heterogeneity and low water injectivity. Near-miscible flooding is proposed considering the wide range of CO2 content (24–90 mol%) in the production gas.

Slim tube test and slim tube simulation are conducted successively to determine the minimum miscible pressure (MMP) of the production gas and oil samples from the targeted reservoir. The relationship of displacement efficiency (DE), interfacial tension (IFT) and displacement pressure are provided and chosen as the basis for the division of the pressure interval of near-miscible flooding. The lower limit of the CO2 content in the production gas to achieve near-miscible flooding are determined for the well 29-2E-5 with the well depth of 3308-3330 m. On this basis, an adjustment measures of adding intermediate components of (C2-C6) is proposed and assessed. The amount of the adding components is calculated and provided correspondingly.

Boundaries of the pressure region of near-miscible flooding are obtained for different CO2 contents. Considering the reservoir conditions (112.1 °C, 31.96 MPa), the lower CO2 content of 64% is estimated to be able to achieve near-miscible flooding for the targeted well. Accordingly, 2.3, 6.5, and 10.3 mol% of (C2-C6) are determined to be the lowest amounts for the adding components to achieve near-miscible injection for the CO2 contents of 55%, 40%, and 24%, respectively.

Thus, the evaluation of the feasibility and optimization measures of near-miscible flooding by production gas re-injection with varying CO2 content in a newly discovered offshore reservoir was conducted. Specific regions in the vicinity of MMP for impure CO2 near-miscible flooding on the basis of comprehensive analysis of displacement efficiency and IFT from the views of both engineering and physicochemical were determined.
Development and Evaluation of an Iridium Oxide Based Chemical Sensor for Downhole CO2 Monitoring
Authors: Wang Sai , Ling Kegang , Liu Ning , Wang Hongsheng
Published: August 2017

Geological carbon sequestration represents a long-term storage of CO2, in which large-scale CO2 is injected into the subsurface geologic formations, such as the deep saline aquifers or depleted oil and gas reservoir. In the CO2 sequestration process, the injected CO2 is expected to remain in the reservoir and not to migrate to the earth surface. To better understand the CO2 movement undersurface and obtain real time information in carbon sequestration, an iridium oxide-based Severinghaus-type CO2 chemical sensor was constructed and tested in this study.

The CO2 sensor was designed and constructed based on the intersection inspiration from electrochemistry idea. The principle of the CO2 sensor design is dramatically rely on the pH detection of the electrolyte solution which generated by the hydrolysis process of CO2. The developed CO2 sensor includes a couple of Iridium-Oxide electrodes. To meet the working purpose, iridium oxide nanoparticles was prepared and electrodeposited for the thin IrO2 film generation on the surface of metal substrate. The other critical parts, such as a thin gas-permeable silicone membrane, a porous metal supporting material, and the bicarbonate-based electrolyte solution are prepared for the sensor's preparation. The assembled sensor was tested in aqueous solution with different CO2 concentrations. Then the sensor was settled in harsh, high-pressure environments, in order to invest the performance of the CO2 sensor under reservoir conditions.

Introduction

The definition of CO2 sequestration was the whole process of the CO2 capture and the CO2 long-term storage [1]. It had been treated as a potential method to decelerate the accumulation process of greenhouse gas which generated from the fossil fuels burning and other source [2]. While for the geologic sequestration, it means to put the captured CO2 in the geological formation for the aim of long-term storage.
Numerical Simulation and Performance Evaluation of CO2 Huff-n-Puff Processes in Unconventional Oil Reservoirs
Authors: Cao Mengjing , Wu Xiaodong , An Yongsheng , Zuo Yi , Wang Ruihe , Li Peng
Published: August 2017

Unconventional oil, such as tight oil and shale oil, has become one of the most significant contributors of oil reservoirs and production growth. Due to low porosity and ultra-low permeability, unconventional oil reservoirs require multistage hydraulic fracturing technique to maximize production. However, the primary recovery remains very low to narrow the profit margin heavily. Although CO2 huff-n-puff process holds great potential to increase oil recovery and has a chance to sequester CO2 to reduce environmental footprint, our current knowledge of the performance of this process is very limited.

With numerical simulation, we performed a series of sensitivity work to present the impacts of reservoir properties, fracture properties and operation parameters such as CO2 injection rate, injection time, soaking time, number of cycle of CO2 on enhanced oil recovery in the tight oil formation. What's more, the method of analysis of variance (ANOVA) was used to evaluate the performance of CO2 huff-n-puff process and beneficial result from CO2 EOR technology. Simulation results showed that bottom hold pressure and injection cycles impose more significant impose on oil recovery increment than injection time, injection rate and production time per cycle. Based on the typical reservoir and fracture properties from tight oil reservoir, the numerical models were established to evaluate the performance of four EOR methods: CO2 huff-n-puff, water huff-n-puff, nanofluids huff-n-puff and water alternating gas (WAG). With the comparison of oil recovery and its increment of four EOR methods and depletion method, it is found that CO2 huff-n-puff method would lead to much more incremental oil recovery than other three methods, which reveals its huge potentials of enhancing oil recovery and improving development profit in unconventional reservoirs. The conclusion of this work has the potential to advance our understanding of the role of CO2 in developing unconventional oil reservoirs, which will benefit both energy economy and environment with CO2 geological sequestration.
Surfactant and a Mixture of Surfactant and Nanoparticles Stabilized-CO2/Brine Foam for Gas Mobility Control and Enhance Oil Recovery
Authors: AlYousef Zuhair , Almobarky Mohammed , Schechter David
Published: August 2017

Injecting carbon dioxide (CO2) into oil reservoirs has the potential to enhance oil recovery (EOR) and mitigate climate change by storing CO2 underground. Despite successes in using CO2 to enhance oil recovery, mobility control remains a major challenge facing CO2 injection projects. The objective of this work is to investigate the potential of using surfactant and a mixture of surfactant and nanoparticles (NPs) to generate foam to reduce gas mobility and enhanced oil recovery.

A newly developed anionic surfactant and a mixture of the surfactant and surface modified silica NPs were used to assess the ability of generating a stable foam at harsh reservoir conditions: sc-CO2 and high temperature. Dynamic foam tests and coreflood experiments were conducted to evaluate foam stability and strength. To measure the mobility of injected fluids in sandstone rocks, the foam was generated by co-injection of sc-CO2 and surfactant, as well as a mixture of surfactant and NPs at 90% quality. The coreflood experiments were conducted using non-fractured and fractured sandstone cores at 1550 psi and 50°C.

Surfactant alone and mixtures of surfactant and NPs were able to generate foam in porous media and reduce CO2 mobility. The mobility reduction factor (MRF) for both cases was about 3.5 times higher than that of injecting CO2 and brine at the same conditions. The coreflood experiments in non-fractured sandstone rocks showed that both surfactant and a mixture of surfactant and NPs were able to enhance oil recovery. The baseline experiment in the absence of surfactant resulted in a total recovery of 71.50% of the original oil in place (OOIP). Using surfactant brought the oil recovery to 76% of the OOIP. The addition of NPs to surfactant resulted in a higher oil recovery still, 80% of the OOIP. In fractured rocks, oil recoveries during secondary production mechanisms for the mixture, the surfactant alone, and sc-CO2 alone were 12.62, 8.41 and 7.21% of the OOIP, respectively.
CO2-EOR in Fractured Ultra-Low Permeability Reservoirs: Problems and Remedial Measures
Authors: Liu Xiaochun , Ma Liping , Tan Junling , Yang Tangying , Li Xiaorong , Hou Jirui , Wei Qi , Hao Hongda , Song Zhaojie , Wang Shitou , Bi Weiyu
Published: August 2017

H-3 Block is an ultra-low permeability reservoir in Changqing oil field, China which had been waterflooded from 2009 and was switched to CO2 flooding in 2013 due to excess water production. However, the nature fractures in NE-SW region have resulted in early CO2 breakthrough and poor production performance. The investigation of CO2 production performance and the method to control CO2 production becomes a key to continue CO2-EOR project.

Outcrop cores are used to perform a series of CO2 flooding experiments at reservoir conditions of pressure, temperature and formation water salinity. Permeability heterogeneity and injection pressure are considered as two variables to affect gas channeling characteristics. It is figured out that producing gas-oil ratio and components analysis of effluent could be used to judge gas channeling and timing to control CO2 production for field use. Starch gel is developed to control CO2 production within nature fractures to improve CO2 swept volume in rock matrix. Ethylenediamine (EDA) is proposed to delay CO2 production within high-permeability zones, and the application boundary as a function of permeability heterogeneity is determined.

Three production stages are clearly stated based on production performance and experimental observation, including gas-free production stage, oil/gas co-production stage, and gas channeling stage. A significant new finding is that oil/gas co-production stage contributes the most to oil recovery. And oil-CO2 mass transfer zone, rather than free CO2, reaches the outlet at this stage, which is proved by color of effluent and chromatographic analysis. For field cases, producing gas-oil ratio and components analysis of effluent at wellhead could help field engineers make a decision: keep producing with caution at oil-gas co-production stage or control the CO2 production at gas channeling stage. The conformance improvement and the increase in injection pressure could remarkably enhance the oil recovery at oil/gas co-production stage. To delay gas channeling and extent oil/gas co-production stage, two-level gas channeling control is presented. A slug of starch gel is first injected to block fractures and then ethylenediamine is injected to react with in-situ CO2 within high-permeability zone. The starch gel, acting as pure viscous fluid, would not leave contamination in rock matrix. And the viscous reactant of ethylenediamine and in-situ CO2 could successfully tune injected CO2 to flood low-permeability zone when permeability ratio is less than 100.
Gouvernance des régimes complémentaires de retraite, relations du travail et conflits de rôle : une enquête québécoise
Authors: Coulombe Daniel , Déom Esther , Hanin Frédéric , Hayden Annette
Published: August 2017

Cette recherche vise à étudier la présence de conflits de rôle au sein des comités de retraite au Québec. Elle met en relation la gouvernance des régimes de retraite et la présence de conflits de rôle entre la représentation collective et la responsabilité fiduciaire du point de vue des membres de comités de retraite. Nous exploitons une particularité de la gestion québécoise, soit l’obligation de créer un comité de retraite sur lequel siègent des membres représentant l’employeur, les syndicats, les travailleurs, les retraités, ainsi que des membres indépendants. À l’aide d’une méthodologie mixte par questionnaire et par entrevue, il a été possible d’analyser les sources et la nature des conflits.

Contrairement à nos anticipations, notre étude ne démontre pas de conflits systématiques causés par la coexistence du système de relations du travail et de la responsabilité fiduciaire des régimes complémentaires de retraite. Les tensions reliées aux relations du travail sont minimes. Nous avons bien identifié quelques enjeux, notamment au niveau du financement des régimes, de la viabilité des régimes, qui relèvent de la confusion des rôles.

Toutefois ces éléments ne sont pas perçus comme des sources de tensions, mais plutôt comme des enjeux à discuter. La qualité de la gouvernance des régimes de retraite dépend des ressources investies par les acteurs des relations du travail dans l’accompagnement des membres des comités de retraite. La recherche sur les conflits de rôle dans la gouvernance des régimes de retraite au Québec montre que la gestion de ces conflits dépend, dans une large mesure, de la qualité de la législation sur l’administration des régimes complémentaires de retraite au Québec et, également, des ressources consacrées à la formation des membres des comités de retraite et des participants aux relations du travail.
Une autre manière de modéliser les réseaux sociaux. Applications à l’étude de co-publications
Authors: Dalud-Vincent Monique
Published: August 2017

Cet article a pour objectif de montrer pourquoi et comment la prétopologie (domaine des mathématiques qui recouvre la théorie des graphes et la topologie) peut apporter une modélisation et un traitement plus souples et mieux adaptés des réseaux sociaux.
Characterization of the Polish Primitive Horse (Konik) maternal lines using mitochondrial D-loop sequence variation
Authors: Cieslak Jakub , Wodas Lukasz , Borowska Alicja , Cothran Ernest G. , Khanshour Anas M. , Mackowski Mariusz
Published: August 2017

The Polish Primitive Horse (PPH, Konik) is a Polish native horse breed managed through a conservation program mainly due to its characteristic phenotype of a primitive horse. One of the most important goals of PPH breeding strategy is the preservation and equal development of all existing maternal lines. However, until now there was no investigation into the real genetic diversity of 16 recognized PPH dam lines using mtDNA sequence variation. Herein, we describe the phylogenetic relationships between the PPH maternal lines based upon partial mtDNA D-loop sequencing of 173 individuals. Altogether, 19 mtDNA haplotypes were detected in the PPH population. Five haplotypes were putatively novel while the remaining 14 showed the 100% homology with sequences deposited in the GenBank database, represented by both modern and primitive horse breeds. Generally, comparisons found the haplotypes conformed to 10 different recognized mtDNA haplogroups (A, B, E, G, J, M, N, P, Q and R). A multi-breed analysis has indicated the phylogenetic similarity of PPH and other indigenous horse breeds derived from various geographical regions (e.g., Iberian Peninsula, Eastern Europe and Siberia) which may support the hypothesis that within the PPH breed numerous ancestral haplotypes (found all over the world) are still present. Only in the case of five maternal lines (Bona, Dzina I, Geneza, Popielica and Zaza) was the segregation of one specific mtDNA haplotype observed. The 11 remaining lines showed a higher degree of mtDNA haplotype variability (2–5 haplotypes segregating in each line). This study has revealed relatively high maternal genetic diversity in the small, indigenous PPH breed (19 haplotypes, overall HapD = 0.92). However, only some traditionally distinguished maternal lines can be treated as genetically pure. The rest show evidence of numerous mistakes recorded in the official PPH pedigrees. This study has proved the importance of maternal genetic diversity monitoring based upon the application of molecular mtDNA markers and can be useful for proper management of the PPH conservation program in the future.
Modeling of residual currents in the Gulf of California using different grid sizes
Authors: Garcia-Silva G , Marinone SG
Published: August 2017

The effect of the mesh size resolution to model residual currents produced by the tides (M2) in the Gulf of California was studied. The grid sizes used range from 14 x 14 to 2 x 2 km. The results show consistent tidal and residual currents among the different grids. In the northern gulf, a well-defined circulation pattern, aligned with the isobaths, emerged. In the archipelago area, an anticyclonic eddy was found northwest of Tiburón Island. The rest of the gulf showed no appreciable residual circulation. Maximum modeled velocities of ~18 cm s–1 were found in the archipelago; the northern gulf velocities were of the order of 1 cm s–1. The 3 x 3 km grid was considered suitable to model the residual currents in the northern gulf.
Density and biomass of the meiofauna of the upper continental slope in two regions of the Gulf of Mexico
Authors: Escobar E , López M , Soto LA , Signoret M
Published: August 2017

A comparative study of the density and biomass of the meiofauna distributed on the upper continental slope of the western and southern Gulf of Mexico was conducted on board the R/V Justo Sierra. A total of 48 samples were obtained with the aid of a Gomex box corer, at depths ranging from 196 to 540 m off the coast of Tamaulipas and Yucatán. Both regions have contrasting hydrographic and sedimentary conditions; the former is of terrigenous nature, while the latter is carbonaceous. The highest density and biomass values (mean = 1,829,216 ± 489,005 ind/m2 and 0.304 f 0.082 gC/m2, respectively) were recorded off Tamaulipas. These parameters were tive to six times lower in order of magnitude in the Yucatán slope. Meiofauna biomass values were significantly correlated with density (r2 = 0.99). Significant differences in density [Fc(1,46) = 38.51, P < 0.005] and biomass [Fc( 1,46) = 37.72, P < 0.005] were recognized between both areas studied. No clear spatial or bathymetric patterns were observed in the meiofaunal components identified in Tamaulipas. This pattern was attributed to the prevailing variable hydrographic conditions and the different organic carbon sources present in the westem region of the Gulf of Mexico. In contrast, the depth and particulate organic carbon of the Yucatán slope exert a significant influence on meiofaunal density and biomass. In this region, predation by larger size classes seems to control the density. The density and biomass values recorded in both regions of the gulf studied fall within the range of previous meiofauna reports from the northern Gulf of Mexico and similar slope habitats of the world oceans.
Detection of Vibrio cholerae 01 in different habitats of Todos Santos Bay, Baja California, Mexico
Authors: Portillo-López A , Lizarraga-Partida L
Published: August 2017

The presence of Vibrio cholerae 01 (Pacini, 1854) in its culturable and nonculturable stages was studied in water, sediment, plankton and mussel samples, from January to August 1995 in Todos Santos Bay, BC, Mexico. Fifty-two samples were analyzed without finding V. cholerae 01; however, non-01 V. cholerae was present in 28.8% of the samples. Forty-three strains of non-01 V. cholerae were isolated, 44% from plankton, 37% from water and 19% from sediment. Non-O 1 V. cholerae was not detected in mussel samples. The highest bacterial concentrations of coliforms, heterotrophic bacteria, Vibrio-like bacteria and the highest number of non-01 V. cholerae were found in the northern part of the bay. The lowest incidence of non-01 V. cholerae, as well as the lowest concentrations of the other bacterial groups were found in the southern part of the bay, where mussels are commercially cultured.
Effects of sedimentation on coral communities of southern Socorro Island, Revillagigedo archipelago, Mexico
Authors: Ochoa-López E , Reyes-Bonilla H , Ketchum-Mejía J
Published: August 2017

This paper documents the disturbances suffered in 1994 by the coral communities of Braithwaite, Vargas Lozano and Binners bays of southern Socorro Island, Revillagigedo Archipelago (18ºN), after an event of excessive sedimentation caused by an input of terrigenous sediments from the island surface. This phenomenon probably occurred because of the severe erosion of the southern zone of Socorro, originated by the overgrazing and transit of the population of feral sheep (Ovis aries L.), whose activities have caused severe soil losses in the locality. The sediment primarily damaged the coral colonies at Braithwaite Bay, and conspicuously diminished the rocky areas suitable for use by other marine invertebrates. The noticeable differences in the development of coral communities from northern and southern Socorro Island may be due to the repeated occurrence of similar events in the past, as the sheep have lived on the island for more than one century. This paper presents the first record of sedimentation damages to marine communities in oceanic islands of the Mexican Pacific.
Biogeography of the stony corals (Scleractinia) of the Mexican pacific
Authors: Reyes-Bonilla H , López-Pérez A
Published: August 2017

This paper presents a complete list of hermatypic coral species, analyzes the biodiversity levels and describes the biogeographic patterns of the group in the Mexican Pacific. The coral fauna of the Mexican Pacific consists of 23 species, which makes this region one of the highest in terms of specific richness within the tropical eastern Pacific. In general, the species are grouped in faunistic units that correspond to the traditional zoogeographic provinces recognized in the region. There is no evidence of effective biogeographic barriers throughout the Mexican Pacific region. Local extinction events, likely caused by the narrow distribution of some species, and perhaps due to the type and frequency of transpacific colonizations, modify the normal processes of community succession, causing the Mexican Pacific to be a highly dynamic zone in terms of its coral fauna.
FDA Perspective on the Regulation of Artificial Intelligence in Health Care and Biomedicine
Authors: Warraich Haider J. , Tazbaz Troy , Califf Robert M.
Published: October 2024

Importance

Advances in artificial intelligence (AI) must be matched by efforts to better understand and evaluate how AI performs across health care and biomedicine as well as develop appropriate regulatory frameworks. This Special Communication reviews the history of the US Food and Drug Administration’s (FDA) regulation of AI; presents potential uses of AI in medical product development, clinical research, and clinical care; and presents concepts that merit consideration as the regulatory system adapts to AI’s unique challenges.

Observations

The FDA has authorized almost 1000 AI-enabled medical devices and has received hundreds of regulatory submissions for drugs that used AI in their discovery and development. Health AI regulation needs to be coordinated across all regulated industries, the US government, and with international organizations. Regulators will need to advance flexible mechanisms to keep up with the pace of change in AI across biomedicine and health care. Sponsors need to be transparent about and regulators need proficiency in evaluating the use of AI in premarket development. A life cycle management approach incorporating recurrent local postmarket performance monitoring should be central to health AI development. Special mechanisms to evaluate large language models and their uses are needed. Approaches are necessary to balance the needs of the entire spectrum of health ecosystem interests, from large firms to start-ups. The evaluation and regulatory system will need to focus on patient health outcomes to balance the use of AI for financial optimization for developers, payers, and health systems.

Conclusions and Relevance

Strong oversight by the FDA protects the long-term success of industries by focusing on evaluation to advance regulated technologies that improve health. The FDA will continue to play a central role in ensuring safe, effective, and trustworthy AI tools to improve the lives of patients and clinicians alike. However, all involved entities will need to attend to AI with the rigor this transformative technology merits.
Application of Community Detection Methods to Identify Emergency General Surgery–Specific Regional Networks
Authors: Han Jiuying , Wan Neng , Horns Joshua J. , McCrum Marta L.
Published: October 2024

Importance

There is growing interest in developing coordinated regional systems for nontraumatic surgical emergencies; however, our understanding of existing emergency general surgery (EGS) care communities is limited.

Objective

To apply network analysis methods to delineate EGS care regions and compare the performance of this method with the Dartmouth Health Referral Regions (HRRs).

Design, Setting, and Participants

This cross-sectional study was conducted using the 2019 California and New York state emergency department and inpatient databases. Eligible participants included all adult patients with a nonelective admission for common EGS conditions. Interhospital transfers (IHTs) were identified by transfer indicators or temporally adjacent hospitalizations at 2 different facilities. Data analysis was conducted from January to May 2024.

Exposure

Admission for primary EGS diagnosis.

Main Outcomes and Measures

Regional EGS networks (RENs) were delineated by modularity optimization (MO), a community detection method, and compared with the plurality-based Dartmouth HRRs. Geographic boundaries were compared through visualization of patient flows and associated health care regions. Spatial accuracy of the 2 methods was compared using 6 common network analysis measures: localization index (LI), market share index (MSI), net patient flow, connectivity, compactness, and modularity.

Results

A total of 1 244 868 participants (median [IQR] age, 55 [37-70 years]; 776 725 male [62.40%]) were admitted with a primary EGS diagnosis. In New York, there were 405 493 EGS encounters with 3212 IHTs (0.79%), and 9 RENs were detected using MO compared with 10 Dartmouth HRRs. In California, there were 839 375 encounters with 10 037 IHTs (1.20%), and 14 RENs were detected compared with 24 HRRs. The greatest discrepancy between REN and HRR boundaries was in rural regions where one REN often encompassed multiple HRRs. The MO method was significantly better than HRRs in identifying care networks that accurately captured patients living within the geographic region as indicated by the LI and MSI for New York (mean [SD] LI, 0.86 [1.00] for REN vs 0.74 [1.00] for HRR; mean [SD] MSI, 0.16 [0.13] for REN vs 0.32 [0.21] for HRR) and California (mean [SD] LI, 0.83 [1.00] for REN vs 0.74 [1.00] for HRR; mean [SD] MSI, 0.19 [0.14] for REN vs 0.39 [0.43] for HRR). Nearly 27% of New York hospitals (37 of 139 hospitals [26.62%]) and 15% of California hospitals (48 of 336 hospitals [14.29%]) were reclassified into a different community with the MO method.

Conclusions and Relevance

Development of optimal health delivery systems for EGS patients will require knowledge of care patterns specific to this population. The findings of this cross-sectional study suggest that network science methods, such as MO, offer opportunities to identify empirical EGS care regions that outperform HRRs and can be applied in the development of coordinated regional systems of care.
Viral entry mechanisms: the role of molecular simulation in unlocking a key step in viral infections
Authors: Valério Mariana , Buga Carolina C. , Melo Manuel N. , Soares Cláudio M. , Lousa Diana
Published: October 2024

Viral infections are a major global health concern, affecting millions of people each year. Viral entry is one of the crucial stages in the infection process, but its details remain elusive. Enveloped viruses are enclosed by a lipid membrane that protects their genetic material and these viruses are linked to various human illnesses, including influenza, and COVID‐19. Due to the advancements made in the field of molecular simulation, significant progress has been made in unraveling the dynamic processes involved in viral entry of enveloped viruses. Simulation studies have provided deep insight into the function of the proteins responsible for attaching to the host receptors and promoting membrane fusion (fusion proteins), deciphering interactions between these proteins and receptors, and shedding light on the functional significance of key regions, such as the fusion peptide. These studies have already significantly contributed to our understanding of this critical aspect of viral infection and assisted the development of effective strategies to combat viral diseases and improve global health. This review focuses on the vital role of fusion proteins in facilitating the entry process of enveloped viruses and highlights the contributions of molecular simulation studies to uncover the molecular details underlying their mechanisms of action.
Replacing manual planning with automatic iterative planning for locally advanced rectal cancer VMAT treatment
Authors: Liu Jiacheng , Wang Ruoxi , Wang Qingying , Yao Kaining , Wang Meijiao , Du Yi , Yue Haizhen , Wu Hao
Published: October 2024

Purpose

To develop and implement a fully automatic iterative planning (AIP) system in the clinical practice, generating volumetric‐modulated arc therapy plans combined with simultaneous integrated boost technique VMAT (SIB‐VMAT) for locally advanced rectal cancer (LARC) patients.

Method

The designed AIP system aimed to automate the entire planning process through a web‐based service, including auxiliary structure generation, plan creation, field configuration, plan optimization, dose calculation, and plan assessment. The system was implemented based on the Eclipse scripting application programming interface and an efficient iterative optimization algorithm was proposed to reduce the required iterations in the optimization process. To verify the performance of the implemented AIP system, we retrospectively selected a total of 106 patients and performed dosimetric comparisons between the automatic plans (APs) and the manual plans (MPs), in terms of dose‐volume histogram (DVH) metrics, homogeneity index (HI), and conformity index (CI) for different volumes of interest.

Result

The AIP system has successfully created 106 APs within clinically acceptable timeframes. The average planning time per case was 36.8 ± 6.5 min, with an average iteration number of 6.8 (±1.1) in plan optimization. Compared to MPs, APs exhibited better performance in the planning target volume conformity and hotspot control (). The organs at risk (OARs) sparing was significantly improved in APs, with mean dose reductions in the femoral heads, the bone marrow, and the SmallBowel‐Avoid of 0.53 Gy, 1.18 Gy, and 1.00 Gy, respectively (). Slight improvement was also observed in the urinary bladder and the small bowel . Additionally, quality variation between plans from different planners was observed in DVH metrics while the APs represented better plan quality consistency.

Conclusion

An AIP system has been implemented and integrated into the clinical treatment planning workflow. The AIP‐generated SIB‐VMAT plans for LARC have demonstrated superior plan quality and consistency compared with the manual counterparts. In the meantime, the planning time has been reduced by the AIP approach. Based on the reported results, the implemented AIP framework has been proven to improve plan quality and planning efficiency, liberating planners from the laborious parameter‐tuning in the optimization phase.
Fixed‐Time State Observer‐Based Robust Adaptive Neural Fault‐Tolerant Control for a Quadrotor Unmanned Aerial Vehicle
Authors: Ranjan Sanjeev , Majhi Somanath
Published: October 2024

This paper presents a fixed‐time state observer‐based robust adaptive neural fault‐tolerant control (RANFTC) for attitude and altitude tracking and control of quadrotor unmanned aerial vehicles (UAVs), considering multiple actuator faults, parametric uncertainty, and unknown external disturbances simultaneously. A novel fixed‐time state error estimation based on sliding mode observer is designed, which is independent of initial conditions. A proportional–integral–derivative (PID) based sliding mode control (SMC) is proposed to handle actuator faults and unknown disturbances in combination with the fixed‐time observer within the fault‐tolerant control (FTC) design scheme. The radial basis function neural network (RBFNN) is employed with the controller to approximate the uncertain parameters of the system. Furthermore, two new adaptive laws are designed to estimate the sudden actuator fault and the unknown upper bound of disturbances independently. Implementing these estimation schemes avoids overestimation, enhances the robustness of the presented controller, and substantially eliminates the control chattering problem. By applying the Lyapunov stability concept, the suggested control strategy guarantees that the states of the quadrotor UAV converge to the origin in a finite time. Finally, simulation studies are conducted to demonstrate the tracking performance and highlight the effectiveness of the proposed FTC design compared to the existing FTC methods.
Electroacupuncture Slows Experimental Myopia Progression by Improving Retinal Mitochondrial Function: A Study Based on Single‐Cell RNA Sequencing
Authors: Hao Jiawen , Xie Yunxiao , Wei Huixia , Yang Zhaohui , Zhang Ruixue , Ma Zhongyu , Zhang Miao , Du Xiaoshi , Yin Xuewei , Liu Jinpeng , Bao Bo , Bi Hongsheng , Guo Dadong
Published: October 2024

This study aimed to establish a complete atlas of retinal cells in lens‐induced myopia (LIM) and electroacupuncture (EA) intervention by single‐cell RNA sequencing (scRNA‐seq) and to explore the potential mechanism of EA in improving experimental myopia progression in guinea pigs. scRNA‐seq is used to assess changes in individual cellular gene levels in the retina of LIM‐ and EA‐treated guinea pigs. In addition, the role of EA in slowing myopia progression by improving retinal mitochondrial function is further investigated. scRNA‐seq identified ten cell clusters in the retina of LIM and EA guinea pigs and mitochondrial respiratory chain‐related genes in Cones and Muller‐glia cells—Cytochrome oxidase subunit III (COX3), NADH dehydrogenase subunit 4 (ND4), and NADH dehydrogenase subunit 2 (ND2) are closely related to lens‐induced myopia. A comprehensive atlas in the retina of LIM and EA guinea pigs at a single‐cell level is established, and the positive role of EA in improving retinal mitochondrial function to slow the experimental myopia progression in guinea pigs is revealed.
Surface Defects‐Induced Photoactivation of Carbon Dots‐NiFe2O4 Nanocomposite: Synthesis, Mechanism and Applications
Authors: Xie Ruyan , Zhang Shuzhe , Song Yanhua , Zhang Xiaozhen , Sheng Shihou , Zou Haifeng
Published: October 2024

The optical properties of quantum dots are significantly influenced by photoactivation. However, the progress in the development of photoactivation carbon dot (CDs) is still stagnant. Herein, a method for preparing photoactivated CDs/NiFe2O4 by introducing affluent defects onto the surface of CDs through modification with NiFe2O4, extremely filling the gap of photoactivated CDs is proposed. Interestingly, a fantastic fluorescence detection strategy in a unique “OFF‐ON‐OFF” mode, combined with Ag+‐assisted fluorescence enhancement, to establish a dual‐channel regulation mechanism for ultra‐sensitive detection of Hg2+ is first proposed. By increasing surface traps and non‐radiative recombination, defect‐induced manipulation on the surface of CDs creates favorable conditions for enhancing photoactivation capacity. Unexpectedly, the CDs/NiFe2O4 shows a 25‐fold enhancement in fluorescence intensity after exposure to UV‐lamp. Compared to CDs/NiFe2O4, Ag+‐assisted photoactivation CDs/NiFe2O4 exhibits superior selectivity and sensitivity for Hg2+ detection, with low detection limits of 0.7 nM. Moreover, TiO2@CDs/NiFe2O4 catalyst is successfully prepared by anchoring CDs/NiFe2O4 onto the surface of TiO2, which demonstrates efficient degradation of tetracycline within 90 min under visible light irradiation, with a degradation rate of 98.3%. This work first provides a novel defects modification strategy for developing highly active photoactivated CDs technology that is significant for future environmentally sensitive applications.
Self‐Powered Iontronic Capacitive Sensing Unit with High Sensitivity in Charge‐Output Mode
Authors: Liu Jianxing , Liu Haiyang , Guo Haoyu , Huang Linwei , Lu Tongqing
Published: October 2024

The operation of iontronic capacitive sensors typically requires an external alternating current (AC) power source, resulting in additional energy consumption and AC‐frequency‐related sensing performance. Here, a class of self‐powered iontronic capacitive sensing units (SICSUs) is proposed based on a dynamic electric double layer (EDL), with a significant charge sensitivity of up to 24270 pC N−1, surpassing most piezoelectric materials by nearly 10 times. The effects of various design parameters and loading conditions on the sensing performance of the SICSUs are systematically investigated. The EDL at the hydrogel‐electrode interface is characterized in situ, revealing the underlying mechanism for high sensitivity and linearity. The capability of SICSUs in detecting diverse human‐related mechanical loads is demonstrated. Furthermore, a robotic hand equipped with a SICSU‐based artificial algesia sensor is fabricated to mimic the withdrawal reflex behavior of a human hand when its skin detects noxious stimuli caused by sharp objects.
Photo‐Curable Fluorinated High‐k Polyimide Dielectrics by Polar Side Substitution Effect for Low‐Voltage Operating Flexible Printed Electronics
Authors: Ye Heqing , Kwon Hyeok‐jin , Kim Yejin , Park Su Bin , Wang Rixuan , Benliang Hou , Gwon Ji‐eun , Wu Kaibin , Wu Yizhang , Zhang Hongjian , Chang Dong Wook , Lim Bogyu , Lee Seung Woo , Kim Se Hyun
Published: October 2024

Polyimide‐based dielectric films are widely used in various thin film devices including organic field‐effect transistors (OFETs) owing to their promising thermal/chemical stability, mechanical flexibility, and insulating properties. On the other hand, considerable attention is paid to lowering the process temperature to allow coating on plastic substrates because high‐temperature annealing (≈200 °C) is usually required to convert precursors to polyimide films with those excellent properties. In addition, polyimide‐based dielectric films have low dielectric constants (k) (<4). Therefore, modifying the k properties of polyimide is a critical issue for applications as an insulating thin film for practical transistors. This paper reports a new type of polyimide‐based gate dielectric comprising methacryloyl moiety (PI‐MA) as a side chain for photo‐pattern/processability and high‐k properties. This study shows that the photocured PI‐MA thin films show excellent insulating properties (leakage current densities < 10−8 A cm⁻2 at 4 MV cm⁻1) and high‐k properties (≈8) even without a post‐annealing process. Finally, the use of PI‐MA in printed field‐effect transistors results in high performance with low‐voltage operation (within 5 V) and integrated logic‐gate devices (NOT, NAND, and NOR gates).
Engineered Exosomes with Ouabain for H3K27M‐Mutated DIPG Therapy
Authors: Shan Shaobo , Chen Junge , Qing Guangchao , Xie Luyang , Xia Bozhang , Pan Changcun , Xu Cheng , Fang Hongjuan , Wan Yichen , Yang Yun , Fan Yubo , Liang Xing‐Jie , Zhang Liwei
Published: October 2024

Diffuse intrinsic pontine glioma (DIPG) is a highly lethal tumor that occurs in the brain stem. At present, there is no effective drug for DIPG. In this work, Na/K‐ATPase inhibitor‐ouabain (OB) is found to efficiently kill H3K27M‐mutated DIPG at low doses, inhibit tumor cell proliferation, reduce tumor stemness for the first time, demonstrating its potential as a chemotherapy drug for DIPG. In order to increase the blood–brain barrier (BBB) permeability and tumor accumulation of OB, acidic‐responsive engineered exosomes loaded with OB (OB@EXO‐LCCP) are constructed, which increase the accumulation of OB within the tumor microenvironment of DIPG and efficiently deliver OB to DIPG cells to achieve targeted killing effect. In in vitro experiments, OB@EXO‐LCCP is able to release OB in an acid‐responsive manner and effectively kill DIPG tumor cells. In in vivo experiments, OB@EXO‐LCCP significantly inhibits DIPG growth and prolongs the overall survival of DIPG‐bearing mice. Overall, OB@EXO‐LCCP can promote the BBB permeability and tumor‐targeting ability of OB, thereby enhancing its DIPG‐killing ability and reducing its toxicity. This study provides technical and theoretical information for the precision therapy of DIPG.
Zincophilic Tellurium Interface Layer Enables Fast Kinetics for Ultralow Overpotential and Highly Reversible Zinc Anode
Authors: Chen Jingzhu , Liu Ning , Zhao Siwei , Dong Wujie , Lv Zhuoran , Wan Dongyun , Bi Hui , Huang Fuqiang
Published: October 2024

Corrosion, hydrogen evolution, and dendrite formation seriously affect the Zn anode, significantly limiting the practical application of aqueous zinc ion batteries. Herein, the Zn anode surface is innovatively reconstructed by decorating a zincophilic tellurium layer (Te@Zn) to enhance the Zn deposition kinetics. Theoretical calculations and experimental characterizations demonstrate that the zincophilic Te provides an abundance of anchoring sites for Zn nucleation and homogenizes the interface electric field to suppress dendrite growth. The Te@Zn anode exhibits an ultralow overpotential of 14.8 mV at 1.0 mA cm−2 and 1.0 mAh cm−2 with high Coulombic efficiency, and maintains ultra‐stable operation for over 3600 h at 0.2 mA cm−2 and 0.2 mAh cm−2. The Te@Zn||KVOH full cells and soft–pack batteries also deliver a brilliant rate capability and long cycling stability. The interfacial manipulation strategy using the Te layer on Zn anode surface paves the way for large‐scale energy storage applications.
Design of Electrocatalysts with High Performance Based on Thermodynamics and Kinetics: Progress and Prospects
Authors: Du Minshu , Yu Feihan , Gong Shumin , Liu Feng
Published: October 2024

Efficient and robust electrocatalysts play a central role in clean energy conversion, enabling a number of sustainable processes for future technologies. The traditional explorations of electrocatalyst relying on the trial‐and‐error approaches are definitely tedious and inefficient. Theoretical progresses on reactive thermodynamics and kinetics in recent years have initiated a powerful theory‐guided design strategy of electrocatalysts. Herein, this review first summarizes design principles for reactive activity and stability, presenting the thermodynamics, kinetics, and the synergistic thermokinetic correlation in electrocatalytic reaction. Second, the screening criterion, reasonable design, mechanistic understanding, and performance evaluation of the typical electrocatalysts as divided into the thermodynamics oriented‐, kinetics oriented‐, and thermokinetic correlation oriented‐designs are discussed. The necessity of correlating thermodynamics and kinetics into the rational design and mechanism clarification is highlighted. Finally, the conclusions and perspectives of the development of highly efficient electrocatalysts are proposed.
Macrophage Membrane‐Biomimetic Multi‐Layered Nanoparticles Targeting Synovial Angiogenesis for Osteoarthritis Therapy
Authors: Liao Junyi , Zhu Zhenglin , Zou Jing , Liu Senrui , Luo Xuefeng , Bao Wei , Du Chengcheng , Lei Yiting , Huang Wei
Published: October 2024

Osteoarthritis (OA) is an inflammatory and progressive joint disease characterized by angiogenesis‐mediated sustained, chronic, and low‐grade synovitis. Anti‐angiogenesis is emerging as a strategy for attenuating OA progression, but is often compromised by poor targeted drug delivery and immune clearance. Recent studies have identified macrophages formed a “protective barrier” in the lining layer (LL) of synovium, which blocked the communication of joint cavity and sublining layer (SL) of synovium. Inspired by natural mimicry, macrophage membrane‐camouflaged drug delivery is explored to avoid immune clearance. Based on the single cell RNA sequencing, the CD34+ synovial cells are identified as “sentinel cells” for synovium angiogenesis. Consequently, CD34 antibody‐modified macrophage membrane is constructed to target new angiogenesis. Hence, a biomimetic multi‐layered nanoparticle (NP) is developed that incorporates axitinib‐loaded poly(lactic‐co‐glycolic) acid (PLGA) with CD34 antibody modified macrophage membrane (Atb@NP@Raw@CD34) to specifically deliver axitinib (Atb) to the SL and sustain inhibiting angiogenesis without immune elimination. It is found that the Atb@NP@Raw@CD34 can pass through macrophage “barrier”, specifically targeting CD34+ cells, continuously releasing Atb and anti‐angiogenesis in OA synovitis. Furthermore, in vivo data demonstrated that Atb@NP@Raw@CD34 can attenuate joint degeneration by inhibiting synovium angiogenesis‐mediated synovitis. In conclusion, local injection of Atb@NP@Raw@CD34 presents a promising approach for clinically impeding OA progression.
Atomic Dispersed Co on NC@Cu Core‐Shells for Solar Seawater Splitting
Authors: Sun Zhehao , Cheng Shuwen , Jing Xuechen , Liu Kaili , Chen Yi‐Lun , Wibowo Ary Anggara , Yin Hang , Usman Muhammad , MacDonald Daniel , Cheong Soshan , Webster Richard F. , Gloag Lucy , Cox Nicholas , Tilley Richard D. , Yin Zongyou
Published: October 2024

With freshwater resources becoming increasingly scarce, the photocatalytic seawater splitting for hydrogen production has garnered widespread attention. In this study, a novel photocatalyst consisting of a Cu core coated is introduced with N‐doped C and decorated with single Co atoms (Co‐NC@Cu) for solar to hydrogen production from seawater. This catalyst, without using noble metals or sacrificial agents, demonstrates superior hydrogen production effficiency of 9080 µmolg−1h−1, i.e., 4.78% solar‐to‐hydrogen conversion efficiency, and exceptional long‐term stability, operating over 340 h continuously. The superior performance is attributed to several key factors. First, the focus‐light induced photothermal effect enhances redox reaction capabilities, while the salt‐ions enabled charge polarization around catalyst surfaces extends charge carrier lifetime. Furthermore, the Co─NC@Cu exhibits excellent broad light absorption, promoting photoexcited charge production. Theoretical calculations reveal that Co─NC acts as the active site, showing low energy barriers for reduction reactions. Additionally, the formation of a strong surface electric field from the localized surface plasmon resonance (LSPR) of Cu nanoparticles further reduces energy barriers for redox reactions, improving seawater splitting activity. This work provides valuable insights into intergrating the reaction environment, broad solar absorption, LSPR, and active single atoms into a core‐shell photocatalyst design for efficient and robust solar‐driven seawater splitting.