139 research outputs found
Bufalin Induces Reactive Oxygen Species Dependent Bax Translocation and Apoptosis in ASTC-a-1 Cells
Bufalin has been shown to induce cancer cell death through apoptotic pathways. However, the molecular mechanisms are not well understood. In this study, we used the confocal fluorescence microscopy (CFM) to monitor the spatio-temporal dynamics of reactive oxygen species (ROS) production, Bax translocation and caspase-3 activation during bufalin-induced apoptosis in living human lung adenocarcinoma (ASTC-a-1) cells. Bufalin induced ROS production and apoptotic cell death, demonstrated by Hoechst 33258 staining as well as flow cytometry analysis. Bax redistributed from cytosol to mitochondria from 12 to 48 h after bufalin treatment in living cells expressed with green fluorescent protein Bax. Treatment with the antioxidant N-acetyl-cysteine (NAC), a ROS scavenger, inhibited ROS generation and Bax translocation and led to a significant protection against bufalin-induced apoptosis. Our results also revealed that bufalin induced a prominent increase of caspase-3 activation blocked potently by NAC. Taken together, bufalin induced ROS-mediated Bax translocation, mitochondrial permeability transition and caspase-3 activation, implying that bufalin induced apoptosis via ROS-dependent mitochondrial death pathway in ASTC-a-1 cells
Estimating the Lateral Motion States of an Underwater Robot by Propeller Wake Sensing Using an Artificial Lateral Line
An artificial lateral line (ALL) is a bioinspired flow sensing system of an
underwater robot that consists of distributed flow sensors. The ALL has
achieved great success in sensing the motion states of bioinspired underwater
robots, e.g., robotic fish, that are driven by body undulation and/or tail
flapping. However, the ALL has not been systematically tested and studied in
the sensing of underwater robots driven by rotating propellers due to the
highly dynamic and complex flow field therein. This paper makes a bold
hypothesis that the distributed flow measurements sampled from the propeller
wake flow, although infeasible to represent the entire flow dynamics, provides
sufficient information for estimating the lateral motion states of the leader
underwater robot. An experimental testbed is constructed to investigate the
feasibility of such a state estimator which comprises a cylindrical ALL sensory
system, a rotating leader propeller, and a water tank with a planar sliding
guide. Specifically, a hybrid network that consists of a one-dimensional
convolution network (1DCNN) and a bidirectional long short-term memory network
(BiLSTM) is designed to extract the spatiotemporal features of the time series
of distributed pressure measurements. A multi-output deep learning network is
adopted to estimate the lateral motion states of the leader propeller. In
addition, the state estimator is optimized using the whale optimization
algorithm (WOA) considering the comprehensive estimation performance. Extensive
experiments are conducted the results of which validate the proposed
data-driven algorithm in estimating the motion states of the leader underwater
robot by propeller wake sensing.Comment: 10 pages, 8 figure
Miniaturized metachronal magnetic artificial cilia
Biological cilia, hairlike organelles on cell surfaces, often exhibit collective wavelike motion known as metachrony, which helps generating fluid flow. Inspired by nature, researchers have developed artificial cilia as microfluidic actuators, exploring several methods to mimic the metachrony. However, reported methods are difficult to miniaturize because they require either control of individual cilia properties or the generation of a complex external magnetic field. We introduce a concept that generates metachronal motion of magnetic artificial cilia (MAC), even though the MAC are all identical, and the applied external magnetic field is uniform. This is achieved by integrating a paramagnetic substructure in the substrate underneath the MAC. Uniquely, we can create both symplectic and antiplectic metachrony by changing the relative positions of MAC and substructure. We demonstrate the flow generation of the two metachronal motions in both high and low Reynolds number conditions. Our research marks a significant milestone by breaking the size limitation barrier in metachronal artificial cilia. This achievement not only showcases the potential of nature-inspired engineering but also opens up a host of exciting opportunities for designing and optimizing microsystems with enhanced fluid manipulation capabilities
Berberine Nanosuspension Enhances Hypoglycemic Efficacy on Streptozotocin Induced Diabetic C57BL/6 Mice
Berberine (Ber), an isoquinoline derivative alkaloid and active ingredient of Coptis, has been demonstrated to possess antidiabetic activities. However its low oral bioavailability restricts its clinical application. In this report, Ber nanosuspension (Ber-NS) composed of Ber and D-α-tocopheryl polyethylene glycol 1000 succinate (TPGS) was prepared by high pressure homogenization technique. Antidiabetic effects of Ber-NS relative to efficacy of bulk Ber were evaluated in streptozotocin (STZ) induced diabetic C57BL/6 mice. The particle size and zeta potential of Ber-NS were 73.1 ± 3.7 nm and 6.99 ± 0.17 mV, respectively. Ber-NS (50 mg/kg) treatment via oral gavage for 8 weeks resulted in a superior hypoglycemic and total cholesterol (TC) and body weight reduction effects compared to an equivalent dose of bulk Ber and metformin (Met, 300 mg/kg). These data indicate that a low dosage Ber-NS decreases blood glucose and improves lipid metabolism in type 2 diabetic C57BL/6 mice. These results suggest that the delivery of Ber as a nanosuspension is a promising approach for treating type 2 diabetes
Co-processing of raw and washed air pollution control residues from energy-from-waste facilities in the cement kiln
Co-processing of industrial wastes as alternative raw materials in cement manufacture is an example of industrial symbiosis for improved material resource efficiency. Since co-processing introduces impurities from wastes, such as air pollution control residue (APCR) from municipal solid waste combustion, into the cement kiln, a better understanding of their environmental impacts and effects on cement manufacturing and quality is needed. Portland cement clinkers containing 5–35% raw or 5–34% washed APCR were prepared, with formation of all typical minerals, but with effects on clinkering reactions, and increased 2CaO·SiO2 and decreased 3CaO·SiO2 and 3CaO·Al2O3. Raw APCR affected the shape of the 2CaO·SiO2 and 3CaO·SiO2 grains, and cement paste from clinker made with 35% APCR exhibited negligible 28d strength. Pastes from the clinkers with lower contents of APCR or washed APCR had strengths that were lower than that of the control at 7d, similar at 28d (∼90 MPa) and higher at 6 m (up to 120 MPa), consistent with their 2CaO·SiO2 and 3CaO·SiO2 contents. Utilization of minerals in APCR thus comes with a trade-off against cement quality. Volatilisation of S, Cl, Pb was reduced by washing, which fully eliminated volatilisation of Zn. Zn was found mainly in the interstitial phases of the clinker, in solid solution in 4CaO·Al2O3·Fe2O3 or 3CaO·Al2O3. Further investigation is required to determine whether Zn and other incorporated elements may be released from the cement paste when these phases react with water. APCR co-processing may reduce CO2 emissions by avoiding CaCO3 decomposition, but this is an uncertain benefit, which may be outweighed by the detrimental effects of APCR alkalis, Cl, S and metals on cement production and quality. Life cycle environmental impacts associated with washing, and dispersal of contaminants in the built environment through construction materials, are additional concerns
Linking the SO2 emission of cement plants to the sulfur characteristics of their limestones: A study of 80 NSP cement lines in China
In a properly operated new suspension preheater (NSP) cement line, the SO2 emission is mainly originated from sulfides in the raw meal, and limestone, occupying about 85% wt. of the raw meal, is the dominant sulfur source. However, the sulfur characteristics of limestones and then their influences on the SO2 emission have not been clarified yet. In the present study, 80 NSP cement lines with SO2 emission > 200 mg/Nm3 were recorded, the sulfur content and species as well as pyrite morphology of limestones were analyzed and then correlated to their resulting SO2 emission. The results show that the SO2 emission of stack gas increases linearly with the SO3 content of limestone used, and sulfates lead to a 50% reduction in SO2 emission relative to sulfides. Compared with average SO2 emission, euhedral pyrite leads to a slightly higher SO2 emission, whereas metasomatic pyrite results in a lower SO2 emission, which can be attributed to the effects of accompanying elements (Ti, F, K, and Al etc.) on the desulfurization reaction and clinkerization in the whole NSP cement line. The relationships proposed can be used to predict the SO2 emission based on the sulfur characteristics of limestone and to rationally utilize high-sulfur limestone in cement industry
Treatment Outcomes with Standard of Care in Relapsed/Refractory Diffuse Large B-Cell Lymphoma: Real-World Data Analysis
INTRODUCTION: Despite new therapies for relapsed or refractory (R/R) diffuse large B-cell lymphoma (DLBCL), treatments with chemotherapy, single-agent rituximab/obinutuzumab, single-agent lenalidomide, or combinations of these agents continue to be commonly used.
METHODS: This retrospective study utilized longitudinal data from 4226 real-world electronic health records to characterize outcomes in patients with R/R DLBCL. Eligible patients were diagnosed with DLBCL between January 2010 and March 2022 and had R/R disease treated with ≥ 1 prior systemic line of therapy (LOT), including ≥ 1 anti-CD20-containing regimen.
RESULTS: A total of 573 patients treated with ≥ 1 prior LOT were included (31.2% and 13.4% with ≥ 2 and ≥ 3 prior LOTs, respectively). Median duration of follow-up was 7.7 months. Most patients (57.1%) were male; mean standard deviation (SD) age was 63 (14.7) years. Overall and complete response rates (95% confidence interval (CI) were 52% (48-56) and 23% (19-27). Median duration of response and duration of complete response were 3.5 and 18.4 months. Median progression-free and overall survival (95% CI) was 3.0 (2.8-3.3) and 12.9 (10.1-16.9) months, respectively. Patients with a higher number of prior LOTs, primary refractoriness, refractoriness to last LOT, refractoriness to last anti-CD20-containing regimen, and prior CAR T exposure had worse outcomes (i.e., challenging-to-treat R/R DLBCL) compared with those without these characteristics.
CONCLUSIONS: Outcomes in patients with R/R DLBCL treated with chemotherapy, single-agent rituximab/obinutuzumab, single-agent lenalidomide, or combinations of these agents remain poor, especially for those with challenging-to-treat R/R DLBCL. These findings underscore the unmet need for new, safe, and effective therapies, especially for challenging-to-treat R/R DLBCL populations
Programmable metachronal motion of closely packed magnetic artificial cilia
Despite recent advances in artificial cilia technologies, the application of metachrony, which is the collective wavelike motion by cilia moving out-of-phase, has been severely hampered by difficulties in controlling closely packed artificial cilia at micrometer length scales. Moreover, there has been no direct experimental proof yet that a metachronal wave in combination with fully reciprocal ciliary motion can generate significant microfluidic flow on a micrometer scale as theoretically predicted. In this study, using an in-house developed precise micro-molding technique, we have fabricated closely packed magnetic artificial cilia that can generate well-controlled metachronal waves. We studied the effect of pure metachrony on fluid flow by excluding all symmetry-breaking ciliary features. Experimental and simulation results prove that net fluid transport can be generated by metachronal motion alone, and the effectiveness is strongly dependent on cilia spacing. This technique not only offers a biomimetic experimental platform to better understand the mechanisms underlying metachrony, it also opens new pathways towards advanced industrial applications.</p
Research progress and future study of carbon emission reduction for UCG
The integration of underground coal gasification (UCG) and carbon emission reduction is expected to become an excellent green energy technology during the transitional stage from the current to the arrival of carbon neutrality, and even play an important role in the longer history of carbon neutrality in the future. Looking back at the research history and current situation, the systematic strategy for UCG emission reduction has been basically formed, which can be summarized into five specific approaches. Among them, the targeted underground in-situ regulation can reduce the CO2 release and promote the quality and yield increase of UCG synthesis gas, and the relevant strategies and approaches can be summarized as the Carbon Regulation and Reduction (CRR). There are many research achievements on the supercritical gas storage of UCG-CO2 in underground space, mainly focusing on storage media, storage space, storage capacity, etc., with some discussions for storage mechanisms. The mineralization and storage of UCG-CO2 in underground space are not constrained by the harsh conditions of geological stability and sealing, and there is a potential dual effect of both carbon sequestration and gas conversion, but there are not many research results yet. The previous exploration of UCG-CO2 reinjection, utilization and storage focuses on two aspects, such as enhancing coalbed methane production and improving the production of UCG synthesis gas, and a series of explorations have been initiated for the emission reduction and utilization of CO2 from the tail gas of UCG hydrogen production in recent years. The CRR, as an active emission reduction strategy, targetedly reduces the CO2 concentration in the UCG synthesis gas by adjusting the gasifying agent and its injection method, and there are many theoretical achievements and preliminary on-site verification, which are expected to become a practical clean coal technology that integrates clean energy production and carbon reduction. Reviewing the progress and analyzing the shortcomings, the scientific and technological research for UCG carbon emission reduction has made many substantial achievements, but also still faces some challenges of sustainable development, and the future study should focus on four aspects. One is to prioritize the development of UCG-CO2 underground conversion and utilization technology with a focus on the UCG-CRR based on feasibility. The second is to focus on the shortcomings and to strive for the breakthrough of the collaborative mechanism and key technological bottlenecks of both UCG emission reduction and synthesis gas quality improvement. The third is to make solid progess and promote the prior implementation of UCG-CRR pilot tests and engineering demonstrations for the achievement of practical results step by step. The fourth is to ensure the implementation and establishment of the “trinity” policy support system for the UCG emission reduction consisting of carbon neutrality and management strategy, special science and technology action plans, and professional talent training
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