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In order to improve the compactness and performance of the intake system of turbocharged diesel engines, an integrated intercooler intake system is provided. Porous media computational fluid dynamics (CFD) model is used to analyze the flow and heat exchange performance of the integrated intercooler. The flow resistance, pressure fluctuation, temperature and pressure distribution of integrated intercoolers with different structures are compared by CFD simulation. The simulation results show that the best performance is achieved by the structure with central air intake with a baffle. Experimental study has been carried out to investigate the steady and transient performance of diesel engine with the original or integrated intercooler intake system. The test results show that with the use of the integrated intercooler intake system, the brake specific fuel consumption can be reduced by 5.9 g/kW·h at the rated condition, and the response time is reduced by 20.4 % under medium speed loading process.

The supercritical carbon dioxide (S-CO2) Brayton cycle has become one of the most promising power generation systems in recent years. Owing to the high density of S-CO2, the turbine operates with a lower flow coefficient and a reduced blade height compared to conventional gas turbines, leading to relatively higher tip leakage and secondary flow losses. A properly designed partial admission scheme can increase blade height and improve turbine efficiency. In this study, the effects of partial admission ratio on the performance and flow characteristics of a partial admission S-CO2 turbine were investigated using numerical methods. The results indicate that the decline in turbine efficiency accelerates when the partial admission rate falls below 0.3. Furthermore, the maximum blade torque begins to decrease once the partial admission ratio drops below 0.1. Stronger tip passage vortices and a large-scale leakage vortex were identified in the passage located at the sector interface. Blade loading analysis revealed a reduction in pressure on the pressure surface of blades just entering the active sector, and a significant increase in suction surface pressure for blades about to exit the active sector. These pressure variations result in reduced blade torque near the boundaries of the active sector.

Alternative splicing represents a critical posttranscriptional regulation of gene expression, which contributes to the protein complexity and mRNA processing. Defects of alternative splicing including genetic alteration and/or altered expression of both pre-mRNA and trans-acting factors give rise to many cancers. By integrally analyzing clinical data and splicing data from TCGA and SpliceSeq databases, a number of splicing events were found clinically relevant in tumor samples. Alternative splicing of KLK2 (KLK2_51239) was found as a potential inducement of nonsense-mediated mRNA decay and associated with poor survival in prostate cancer. Consensus K-means clustering analysis indicated that alternative splicing events could be potentially used for molecular subtype classification of cancers. By random forest survival algorithm, prognostic prediction signatures with well performances were constructed for 31 cancers by using survival-associated alternative splicing events. Furthermore, an online tool for visualization of Kaplan–Meier plots of splicing events in 31 cancers was explored. Briefly, alternative splicing was found of significant clinical relevance with cancers.

Ducted fans have been widely used in VTOL aircraft due to the high propulsion efficiency and safety. The efficiency and stability of ducted fans deteriorate in some flight conditions such as hovering in crosswinds or ground effect. It is necessary to optimize the ducted fan’s structures or apply flow control methods for better adaptions to the typical conditions. This paper presents a detailed review on the ducted fan technology for VTOL applications, especially the methods for improving its efficiency and stability. We first simplified the classification categories based on boundary conditions instead of flight conditions, since the new classification method covers more situations and is easier to distinguish flow field characteristics. The flow characteristics, thrust properties and the optimal structures under different boundary conditions were summarized and discussed. Finally, new configurations and flow control methods for increasing the efficiency and stability were introduced. The newly proposed integration design between the ducted fan and the motor was emphasized for increasing the power density of the ducted fans. This review would be helpful to improve our understanding of the relationship between the structures, flow characteristics and thrust properties of ducted fans under different flight conditions, and inspires scientists to design high-efficiency and high-stability propulsion systems with ducted fans.

Forest and grass systems are globally significant carbon-sequestering ecosystems, crucial for mitigating climate change and optimizing ecological management. To clarify the research history, major contributing groups, and research hotspots related to carbon sequestration in global forest and grass systems, this study utilizes the core ensemble of the Web of Science database as its data source. Employing bibliometric methodology and software, such as VOSviewer 1.6.20 and CiteSpace 5.7.R1, we analyzed the development of 594 relevant publications from 2010 to 2024, focusing on their developmental lineage, research groups, current research status, and visualizing and analyzing research hotspots and frontiers. The results indicate that the volume of the literature on carbon sequestration in forest and grass systems generally follows the pattern of a logistic growth curve, demonstrating an upward trend from 2010 to 2024. The primary contributors consist of 400 researchers, including Nath, Arun Jyoti, and Ajit, as well as 378 research organizations across 42 countries, including China, the USA, and India. China’s contribution to this field is rapidly increasing, accounting for over 20% of the total articles, with ‘Chinese Acad Sci’ and ‘Univ Chinese Acad Sci’ being the most prominent contributors, together representing 10.45% of the total publications in this field. The 179 journals, including Agroforestry Systems and Forests, serve as a significant platform for academic exchange in the development of this field. The predominant research directions are found in the areas of ‘Environmental Sciences & Ecology’ and ‘Agriculture’, which collectively account for over 50% of the publications. Additionally, research focused on ‘Sequestration’ is increasingly examining the relationship between carbon sequestration in forest and grassland systems and factors such as climate change, ecosystem productivity, and biodiversity. The keyword clusters ‘#0 ferralsol’ and ‘#4 forest ecosystem’ have consistently represented important research directions throughout this period. A total of 21 keywords were identified, with ‘land use change’ exhibiting the highest intensity at 4.4524. Future research should not only prioritize the integration of the impacts of global climate change but also enhance collaboration among authors and institutions. Furthermore, it is essential to promote multidisciplinary and cross-regional collaborative innovations by leveraging emerging technologies such as AI and genetic engineering.

ABSTRACT Background: Patients with schizophrenia have deficits in identifying and recognizing emotional facial expressions. Aim: This study aimed to explore the event-related potential (ERP) responses of patients with schizophrenia (SZ) and healthy controls (HC) using the Chinese Facial Affective Picture System (CFAPS). Methods: This study included 30 SZs and 31 HCs. We asked them to complete the task based on the oddball paradigm, in which three emotional faces (happy, fearful, and neutral) were used as target stimuli. Additionally, the amplitude and latency of the N170 component and the P300 component were recorded synchronously. Results: Compared with HCs, SZs had significantly smaller amplitudes of N170 and P300 to all facial expressions. The pairwise comparison revealed that fearful faces could trigger a significantly larger P300 amplitude in HCs than neutral faces, while the such a difference was not found in SZs. Conclusion: These findings indicated that SZs had a noticeable deficiency in the structural coding of face recognition and available attentional resources.

Ducted fans have been widely used in unmanned aerial vehicles (UAVs) for various operations due to the high efficiency, low noise and high safety. Proximity effects caused by the confined environment, including the ceiling effect (CE), bring significant interference to the aerodynamic performance of ducted fans, which serves as a main challenge to stability. In this study, the computational fluid dynamic simulation with the sliding mesh technique and the Unsteady Reynolds Averaged Navier-Stokes (URANS) method is conducted to evaluate the ceiling effect. Time-averaged simulation results show that the ceiling effect results in the increase of both rotor thrust and duct thrust. Transient simulation results show that there is a critical distance of 0.4 rotor radius. The ceiling effect leads to little fluctuation in thrust for distances greater than 0.4 rotor radius, but substantial unsteadiness in the flow field for distances less than 0.4 rotor radius. The unsteady movement of vortex structures results in thrust fluctuations with frequencies typically lower than the blade passing frequency of 200 Hz. The fluctuation accounts for up to 40% of the total thrust. The results are essential to the flight controller design and UAV path planning for enhancement of flight stability in ceiling effect.

In this study, the cold-start process of a polymer electrolyte fuel cell has been numerically investigated under various ambient temperatures and operating currents, ranging from subzero to 283 K. The water desorbed from the electrolyte, when the cell temperature is below the freezing point, is assumed to exist in a state of either supercooled water or ice. The evolution of cell voltage, temperature, membrane water content, and the averaged volume fraction of supercooled water or ice in the catalyst layer and gas diffusion layer are presented. The results indicate that the cold-start process may fail due to ice blocking of the cathode catalyst layer when the desorbed water is in the form of ice and the ambient temperature is sufficiently low. However, when the desorbed water is in a supercooled state, it can diffuse from the cathode catalyst layer to the cathode gas diffusion layer, avoiding water clogging and enabling a successful cold-start process. During the cold-start process, as the ice undergoes a melting process, the membrane water content inside the membrane would increase rapidly, and a larger operation current with anode gas humidification is helpful to the cold-start process.

The low abundance of glycopeptides in biological samples makes it necessary to enrich them before further analysis. In this study, the polymeric hydrophilic ionic liquid-modified magnetic (Fe 3 O 4 @MPS@PMAC) nanoparticles were synthesized via a one-step reflux-precipitation polymerization. Owing to the excellent hydrophilicity and strong electrostatic interaction toward glycopeptides of the polymerized hydrophilic ionic liquid, [2-(methacryloyloxy) ethyl] trimethylammonium chloride (MAC), the synthesized Fe 3 O 4 @MPS@PMAC nanoparticles exhibited outstanding performance in glycopeptide enrichment with high detection sensitivity (10 fmol), large binding capacity (100 μg mg −1 ) and satisfied enrichment recovery (approximately 82%). Furthermore, the newly developed Fe 3 O 4 @MPS@PMAC nanoparticles were applied for the glycopeptide enrichment of HeLa exosome proteins. A total of 1274 glycopeptides from 536 glycoproteins were identified in three replicate analyses of 50 μg of HeLa exosome proteins. These results demonstrate the potential of Fe 3 O 4 @MPS@PMAC nanoparticles for both glycoproteomic analysis and exosome research.

Proton exchange membrane fuel cell (PEMFC) powered propulsion has gained increasing attention in urban air mobility applications in recent years. Due to its high power density, ultra-thin heat pipe technology has great potential for cooling PEMFCs, but optimizing the limited internal cavity of the heat pipe remains a significant challenge. In this study, a three-dimensional multiphase model of the heat pipe cooled PEMFC is built to evaluate the impact of three internal structures, layered, spaced, and composite, of ultra-thin heat pipes on system performance. The results show that the heat pipe cooling with the composite structure yields a lower thermal resistance and a larger operating range for the PEMFC system compared to other internal structures because of more rational layout of the internal cavity. In addition, the relationship between land to channel width ratio (LCWR) and local transport property is analyzed and discussed based on composite structural heat pipes. The heat pipe cooled PEMFC with a LCWR of 0.75 has a significant advantage in limiting current density and maximum power density compared to the LCWRs of 1 and 1.33 as a result of more uniform in-plane distributions of temperature and liquid water within its cathode catalyst layer.