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Multi-level inverters (MLIs) have been widely used in recent years due to their various advantages in industrial and grid-connected applications. Traditional MLI topologies are being hampered by the rapid surge of renewable energy systems (RES) as a result of performance difficulties such as poor power reliability, an economically unviable structure, and a lack of efficiency. These difficulties are due to the traditional MLI topologies’ inability to keep up with the increasing demand for RES. Because of concerns about performance and limitations posed by classic MLI topologies, researchers have found themselves driven to the idea of building innovative hybrid MLI topologies. This study provides a comprehensive analysis of multilevel inverter systems that are wired into the main power supply. Grid-connected inverter types and their configurations are discussed in depth in this review. Diverse multi-level inverter topologies, as well as the different approaches, are divided into various categories and discussed in depth. Additionally, a number of control reference frames for inverters were brought forward for discussion. Furthermore, different inverter control strategies were investigated, followed by a tabular summary of recent developments in the inverter-related literature for the convenience of the readers. Moreover, the recently proposed grid-connected multi-level inverter systems were discussed including their findings and innovations. In conclusion, a brief description of the study’s scope was offered and research directions for future studies were provided.

Urban expansion and changes in land use/land cover (LULC) have intensified in recent decades due to human activity, influencing ecological and developmental landscapes. This study investigated historical and projected LULC changes and urban growth patterns in the districts of Multan and Sargodha, Pakistan, using Landsat satellite imagery, cloud computing, and predictive modelling from 1990 to 2030. The analysis of satellite images was grouped into four time periods (1990–2000, 2000–2010, 2010–2020, and 2020–2030). The Google Earth Engine cloud-based platform facilitated the classification of Landsat 5 ETM (1990, 2000, and 2010) and Landsat 8 OLI (2020) images using the Random Forest model. A simulation model integrating Cellular Automata and an Artificial Neural Network Multilayer Perceptron in the MOLUSCE plugin of QGIS was employed to forecast urban growth to 2030. The resulting maps showed consistently high accuracy levels exceeding 92% for both districts across all time periods. The analysis revealed that Multan’s built-up area increased from 240.56 km 2 (6.58%) in 1990 to 440.30 km 2 (12.04%) in 2020, while Sargodha experienced more dramatic growth from 730.91 km 2 (12.69%) to 1,029.07 km 2 (17.83%). Vegetation cover remained dominant but showed significant variations, particularly in peri-urban areas. By 2030, Multan’s urban area is projected to stabilize at 433.22 km 2 , primarily expanding in the southeastern direction. Sargodha is expected to reach 1,404.97 km 2 , showing more balanced multi-directional growth toward the northeast and north. The study presents an effective analytical method integrating cloud processing, GIS, and change simulation modeling to evaluate urban growth spatiotemporal patterns and LULC changes. This approach successfully identified the main LULC transformations and trends in the study areas while highlighting potential urbanization zones where opportunities exist for developing planned and managed urban settlements.

All kinds of flour products which are made of wheat flour have already become the staple food on people's dining table. With the improvement of living standard, the quality requirements for the flour products have gradually improved. In addition to the production technique, the quality of wheat flour as the raw material is also very important for the quality of flour products. This paper briefly introduced wheat flour and two main components that affected its quality: starch and protein. Then, the related quality of starch and protein and the quality of corresponding flour products were tested for five kinds of wheat flour. The experimental results showed that the quality indexes of five kinds of wheat flour were obviously different and representative. The regression analysis on the quality data of wheat flour and flour products showed that the water absorption of flour decreased with the increase of total starch content, dry gluten content and gluten index, the water solubility of flour decreased with the increase of total starch content and gluten index and increased with the increase of ratio of amylose to amylopectin, and the radial expansion rate of the flour products decreased with the increase of wet gluten content. To sum up, the quality of wheat flour will affect the water absorption, water solubility and radial expansion rate of flour products in the production process.

Wireless Power Transfer (WPT) systems often face performance limitations due to the right-half-plane zero (RHPz) in conventional constant-current-fed Buck converters, which can lead to negative undershoot and a slow dynamic response. In this paper, we propose a Buck converter topology with an additional active switch in series with the input capacitor. This mechanism-level modification effectively mitigates the RHPz. The operating modes, steady-state behavior, and small-signal characteristics of the converter are systematically analyzed. A tailored control strategy enables independent regulation of input and output capacitor charging times, supporting improved voltage regulation. Experimental results indicate that the proposed converter reduces settling time by approximately 83%, substantially suppresses negative undershoot, and maintains stable voltage regulation under reference step changes and load transients. The converter maintains high efficiency while demonstrating improved dynamic performance and stability relative to conventional topologies, providing a practical approach for advanced WPT applications.

Effects of convection (forced and natural) on dendritic evolution of the Al-Cu alloy were investigated using a phase-field lattice-Boltzmann approach. The non-linear coupled equations were solved by applying a parallel and adaptive mesh refinement algorithm. Important physical aspects including dendritic fragmentation, splitting, and formation of solute plumes were simulated. Results showed that the dendritic growth patterns under convection exhibited remarkable difference from those without convection. The presence of flow led to variation of solute diffusion and upstream–downstream dendritic growth difference, which further influenced the development of dendritic arms and multi-dendritic competitive growth. When the convection intensity was magnified, the convection-induced anisotropy became dominated, and the growth patterns changed accordingly to accommodate the local thermodynamic variation.

The earth land area is heterogeneous in terms of elevation; about 45% of its land area belongs to higher elevation with altitude above 500 meters compared to sea level. In most cases, oxygen concentration decreases as altitude increases. Thus, high-altitude hypoxic stress is commonly faced by residents in areas with an average elevation exceeding 2500 meters and those who have just entered the plateau. High-altitude hypoxia significantly affects advanced neurobehaviors including learning and memory (L&M). Hippocampus, the integration center of L&M, could be the most crucial target affected by high-altitude hypoxia exposure. Based on these points, this review thoroughly discussed the relationship between high-altitude hypoxia and L&M impairment, in terms of hippocampal neuron apoptosis and dysfunction, neuronal oxidative stress disorder, neurotransmitters and related receptors, and nerve cell energy metabolism disorder, which is of great significance to find potential targets for medical intervention. Studies illustrate that the mechanism of L&M damaged by high-altitude hypoxia should be further investigated based on the entire review of issues related to this topic.

Direct quantification of terrestrial biosphere responses to global change is crucial for projections of future climate change in Earth system models. Here, we synthesized ecosystem carbon-cycling data from 1,119 experiments performed over the past four decades concerning changes in temperature, precipitation, CO 2 and nitrogen across major terrestrial vegetation types of the world. Most experiments manipulated single rather than multiple global change drivers in temperate ecosystems of the USA, Europe and China. The magnitudes of warming and elevated CO 2 treatments were consistent with the ranges of future projections, whereas those of precipitation changes and nitrogen inputs often exceeded the projected ranges. Increases in global change drivers consistently accelerated, but decreased precipitation slowed down carbon-cycle processes. Nonlinear (including synergistic and antagonistic) effects among global change drivers were rare. Belowground carbon allocation responded negatively to increased precipitation and nitrogen addition and positively to decreased precipitation and elevated CO 2 . The sensitivities of carbon variables to multiple global change drivers depended on the background climate and ecosystem condition, suggesting that Earth system models should be evaluated using site-specific conditions for best uses of this large dataset. Together, this synthesis underscores an urgent need to explore the interactions among multiple global change drivers in underrepresented regions such as semi-arid ecosystems, forests in the tropics and subtropics, and Arctic tundra when forecasting future terrestrial carbon-climate feedback. A synthesis of global change experiments that manipulated temperature, precipitation, carbon dioxide or nitrogen identifies a need to consider site-specific factors and interactions in Earth system models.

As the core observation instrument of the China Space Station Telescope (CSST), the Survey Camera (SC) generates microvibrations that significantly degrade the telescope's imaging quality. Consequently, evaluating the microvibration response of the SC is of critical importance. However, for large-inertia, high-stiffness payloads like the SC with discrete interfaces, structural coupling between the payload and the test system leads to distortions in microvibration test results. Since the vibration transmission under structural coupling is not a simple series superposition, and the transfer functions of each link in the transmission path as well as the coupling correction matrices are difficult to obtain, this paper proposes a semi-physical simulation method for microvibration decoupling. The method first establishes a coupled finite element model of the SC and the test system. The model is iteratively modified based on the results of modal tests and transmissibility tests to ensure consistency with the dynamic characteristics of the actual coupled system. The model is validated through microvibration response tests, and the results show good agreement between the model and the actual system (the RMS deviation of force/torque is less than 5%). After stripping the test system from the modified coupled model, the intrinsic microvibration responses of the SC can be extracted, achieving the dynamic decoupling analysis of the complex coupled system.

Chimeric antigen receptor (CAR)-modified T cells targeting CD19 demonstrate unparalleled responses in B cell malignancies. However, high tumor burden limits clinical efficacy and increases the risk of cytokine release syndrome and neurotoxicity, which is associated with over-activation of the CAR-T cells. The hinge domain plays an important role in the function of CAR-T cells. We hypothesized that deletion of glycine, an amino acid with good flexibility, may reduce the flexibility of the hinge region, thereby mitigating CAR-T cell over-activation. This study involved generating a novel CAR by deletion of two consecutive glycine residues in the CD8 hinge domain of second-generation (2nd) CAR, thereafter named 2nd-GG CAR. The 2nd-GG CAR-T cells showed similar efficacy of CAR expression but lower hinge flexibility, and its protein affinity to CD19 protein was lower than that of 2nd CAR-T cells. Compared to the 2nd CAR-T cells, 2nd-GG CAR-T cells reduced proinflammatory cytokine secretion without diminishing the specific cytotoxicity toward tumor cells in vitro . Furthermore, 2nd-GG CAR-T cells prolonged overall survival in an immunodeficient mouse model bearing NALM-6 when tumor burden was high. This study demonstrated that a lower-flexibility of CD8α hinge improved survival under high tumor burden and reduced proinflammatory cytokines in preclinical studies. While there is potential for improved safety and efficacy, yet this needs validation with clinical trials.

Interleukin-6 (IL-6) trans -signaling modulates immune responses in asthma, yet the mechanisms linking this pathway to Th17 skewing in neutrophilic asthma remain incompletely defined. Here, we evaluated soluble gp130 (sgp130), a selective inhibitor of IL-6 trans -signaling, in vivo and in vitro . A murine neutrophilic asthma model was established by ovalbumin (OVA) sensitization followed by lipopolysaccharide (LPS) plus OVA challenge, and sgp130 was administered intratracheally. Airway neutrophilic inflammation, Th17/Treg responses, and IL-23 expression in lung dendritic cells (DCs) were assessed, and the contribution of Th17 cells was examined by adoptive transfer. In parallel, DCs were cocultured with naïve CD4 + T cells in the presence of Hyper-IL-6 (an IL-6/sIL-6R fusion protein that activates IL-6 trans -signaling) with or without sgp130 to quantify DC-derived IL-23 and Th17 differentiation; additionally, DCs conditioned with Hyper-IL-6 with or without sgp130 were delivered intratracheally to establish a DC-transfer asthma model. In neutrophilic asthma, bronchoalveolar lavage fluid (BALF) levels of IL-6/sIL-6R complex were elevated and positively associated with neutrophil counts and IL-17 production. Blockade of IL-6 trans -signaling with sgp130 attenuated airway neutrophilia, reduced Th17 polarization, increased Treg response, and decreased IL-23 expression in lung DCs, whereas adoptive transfer of Th17 cells partially abrogated these protective effects. Consistently, Hyper-IL-6 increased IL-23 expression in DCs and promoted Th17 differentiation in vitro , both of which were suppressed by sgp130. Moreover, airway transfer of Hyper-IL-6-conditioned DCs induced neutrophilic airway inflammation and Th17 polarization, while transfer of DCs conditioned with Hyper-IL-6 plus sgp130 markedly mitigated these responses. Collectively, IL-6 trans-signaling promotes Th17 polarization in neutrophilic asthma by enhancing DC IL-23 production, thereby driving neutrophilic airway inflammation, and selective inhibition with sgp130 may represent a mechanistically targeted therapeutic strategy.