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Mesenchymal stem cells (MSCs) exhibit substantial potential for osteoarthritis (OA) therapy through cartilage regeneration, yet the realization of optimal therapeutic outcomes is hampered by their limited intrinsic reparative capacities. Herein, MSCs are engineered with circular mRNA (cmRNA) encoding fibroblast growth factor 18 (FGF18) encapsulated within lipid nanoparticles (LNP) derived from a glycerolipid to facilitate OA healing. A proprietary biodegradable and ionizable glycerolipid, TG6A, with branched tails and five ester bonds, forms LNP exhibiting above 9-fold and 41-fold higher EGFP protein expression in MSCs than commercial LNP from DLin-MC3-DMA and ALC-0315, respectively. The introduction of FGF18 not only augmented the proliferative capacity of MSCs but also upregulated the expression of chondrogenic genes and glycosaminoglycan (GAG) content. Additionally, FGF18 enhanced the production of proteoglycans and type II collagen in chondrocyte pellet cultures in a three-dimensional culture. In an OA rat model, transplantation with FGF18-engineered MSCs remarkably preserved cartilage integrity and facilitated functional repair of cartilage lesions, as evidenced by thicker cartilage layers, reduced histopathological scores, maintenance of zone structure, and incremental type II collagen and extracellular matrix (ECM) deposition. Taken together, our findings suggest that TG6A-based LNP loading with cmRNA for engineering MSCs present an innovative strategy to overcome the current limitations in OA treatment.
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Fatores de Crescimento de Fibroblastos , Células-Tronco Mesenquimais , Osteoartrite , Animais , Células-Tronco Mesenquimais/metabolismo , Osteoartrite/terapia , Osteoartrite/patologia , Fatores de Crescimento de Fibroblastos/farmacologia , Fatores de Crescimento de Fibroblastos/metabolismo , Fatores de Crescimento de Fibroblastos/genética , Fatores de Crescimento de Fibroblastos/administração & dosagem , Ratos , Ratos Sprague-Dawley , Nanopartículas/química , RNA Circular/genética , RNA Circular/metabolismo , Condrócitos/metabolismo , Masculino , Condrogênese/efeitos dos fármacos , Transplante de Células-Tronco Mesenquimais , Humanos , Proliferação de Células/efeitos dos fármacos , LipossomosRESUMO
The majority of patients with thyroid cancer can attain a favorable prognosis with a comprehensive treatment program based on surgical treatment. However, the current treatment options for advanced thyroid cancer are still limited. In recent years, chimeric antigen receptor-modified T-cell (CAR-T) therapy has received widespread attention in the field of oncology treatment. It has achieved remarkable results in the treatment of hematologic tumors. However, due to the constraints of multiple factors, the therapeutic efficacy of CAR-T therapy for solid tumors, including thyroid cancer, has not yet met expectations. This review outlines the fundamental structure and treatment strategies of CAR-T cells, provides an overview of the advancements in both preclinical investigations and clinical trials focusing on targets associated with CAR-T cell therapy in treating thyroid cancer, and discusses the challenges and solutions to CAR-T cell therapy for thyroid cancer. In conclusion, CAR-T cell therapy is a promising therapeutic approach for thyroid cancer, and we hope that our review will provide a timely and updated study of CAR-T cell therapy for thyroid cancer to advance the field.
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Imunoterapia Adotiva , Receptores de Antígenos Quiméricos , Linfócitos T , Neoplasias da Glândula Tireoide , Humanos , Neoplasias da Glândula Tireoide/terapia , Neoplasias da Glândula Tireoide/imunologia , Imunoterapia Adotiva/métodos , Receptores de Antígenos Quiméricos/imunologia , Receptores de Antígenos Quiméricos/genética , Animais , Linfócitos T/imunologia , Linfócitos T/transplante , Ensaios Clínicos como Assunto , Resultado do TratamentoRESUMO
The application of resistive random-access memory (RRAM) in storage and neuromorphic computing has attracted widespread attention. Benefitting from the quantum effect, transition metal dichalcogenides (TMD) quantum dots (QDs) exhibit distinctive optical and electronic properties, which make them promising candidates for emerging RRAM. Here, we show a high-performance forming-free flexible RRAM based on high-quality tin disulfide (SnS2) QDs prepared by a facile liquid phase method. The RRAM device demonstrates high flexibility with a large on/off ratio of â¼106 and a long retention time of over 3 × 104 s. The excellent switching behavior of the memristor is elucidated by a charge trapping/de-trapping mechanism where the SnS2 QDs act as charge trapping centers. This study is of significance for the understanding and development of TMD QD-based flexible memristors.
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Lithium metal batteries face problems from sluggish charge transfer at interfaces, as well as parasitic reactions between lithium metal anodes and electrolytes, due to the strong electronegativity of oxygen donor solvents. These factors constrain the reversibility and kinetics of lithium metal batteries at low temperatures. Here, a nonsolvating cosolvent is applied to weaken the electronegativity of donor oxygen in ether solvents, enabling the participation of anionic donors in the solvation structure of Li+. This strategy significantly accelerates the desolvation process of Li+ and reduces the side effects of solvents on interfacial transport and stability. The designed anion-aggregated electrolyte has a unique temperature-insensitive solvation structure and enables lithium metal anodes to achieve a high average Coulombic efficiency at room temperature and -20 °C. A high-loading LiFePO4||Li cell exhibited high reversibility with a 100% capacity retention after 150 cycles at room temperature, -20, and -40 °C. The practical 1 Ah-level LiFePO4||Li pouch-cell delivered 81% and 61% of the capacity at room temperature when charged and discharged at -20 and -40 °C, respectively. This strategy of constructing temperature-insensitive solvation by electronegativity regulation offers a novel approach for developing electrolytes of low-temperature batteries.
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PURPOSE: This study was designed to conduct pooled comparisons of the relative clinical efficacy and safety of computed tomography (CT)-guided localization for pulmonary nodules (PNs) using either coil- or liquid material-based approaches. MATERIAL AND METHODS: Relevant articles published as of July 2023 were identified in the Web of Science, PubMed, and Wanfang databases, and pooled analyses of relevant endpoints were then conducted. RESULTS: Six articles that enrolled 287 patients (341 PNs) and 247 patients (301 PNs) that had respectively undergone CT-guided localization procedures using coil- and liquid material-based approaches prior to video-assisted thoracic surgery (VATS) were included in this meta-analysis. The liquid material group exhibited a significantly higher pooled successful localization rate as compared to the coil group (p = 0.01), together with significantly lower pooled total complication rates (p = 0.0008) and pneumothorax rates (p = 0.01). Both groups exhibited similar rates of pulmonary hemorrhage (p = 0.44) and successful wedge resection (p = 0.26). Liquid-based localization was also associated with significant reductions in pooled localization and VATS procedure durations (p = 0.004 and 0.007). CONCLUSIONS: These data are consistent with CT-guided localization procedures performed using liquid materials being safer and more efficacious than coil-based localization in patients with PNs prior to VATS resection.
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BACKGROUND: Gastric cancer (GC) is one of the most aggressive malignancies with limited therapeutic options and a poor prognosis. Resveratrol, a non-flavonoid polyphenolic compound found in a variety of Chinese medicinal materials, has shown excellent anti-GC effect. However, its exact mechanisms of action in GC have not been clarified. AIM: To identify the effects of resveratrol on GC progression and explore the related molecular mechanisms. METHODS: Action targets of resveratrol and GC-related targets were screened from public databases. The overlapping targets between the two were confirmed using a Venn diagram, and a "Resveratrol-Target-GC" network was constructed using Cytoscape software version 3.9.1. The protein-protein interaction (PPI) network was constructed using STRING database and core targets were identified by PPI network analysis. The Database for Annotation, Visualization and Integrated Discovery database was used for Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) enrichment analysis. A "Target-Pathway" network was created by using Cytoscape 3.9.1. The RNA and protein expression levels of core target genes were observed using the Cancer Genome Atlas and the Human Protein Atlas databases. DriverDBv3 and Timer2.0 databases were used for survival and immune infiltration analysis. Subsequently, the findings were further verified by molecular docking technology and in vitro experiments. RESULTS: A total of 378 resveratrol action targets and 2154 GC disease targets were obtained from public databases, and 181 intersection targets between the two were screened by Venn diagram. The top 20 core targets were identified by PPI network analysis of the overlapping targets. GO function analysis mainly involved protein binding, identical protein binding, cytoplasm, nucleus, negative regulation of apoptotic process and response to xenobiotic stimulus. KEGG enrichment analysis suggested that the involved signaling pathways mainly included PI3K-AKT signaling pathway, MAPK signaling pathway, IL-17 signaling pathway, TNF signaling pathway, ErbB signaling pathway, etc. FBJ murine osteosarcoma viral oncogene homolog (FOS) and matrix metallopeptidase 9 (MMP9) were selected by differential expression analysis, and they were closely associated with immune infiltration. Molecular docking results showed that resveratrol docked well with these two targets. Resveratrol treatment arrested the cell cycle at the S phase, induced apoptosis, and weakened viability, migration and invasion in a dose-dependent manner. Furthermore, resveratrol could exhibit anti-GC effect by regulating FOS and MMP9 expression. CONCLUSION: The anti-GC effects of resveratrol are related to the inhibition of cell proliferation, migration, invasion and induction of cell cycle arrest and apoptosis by targeting FOS and MMP9.
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Due to the alternating loads on pumping units and the integration of new energy sources, multisource DC microgrid pumping unit well groups experience increased fluctuations in voltage and power as well as superimposed peak and valley values. This work presents a distributed control strategy for pumping unit well groups on a multisource DC microgrid based on the weighted moving average algorithm. A centralized control program is implanted in the RTU of the single-well controller of each pumping unit, and communication with each well is realized via SCADA and multicast communication, resulting in a distributed well group system. The real-time power values of the pumping well group are calculated by grouping the power values, and each group is weighted using the total power fluctuation threshold of the well group as the control target. Then, a weighted moving average algorithm is used to predict the next power value and form a table of predicted real-time power spectra. According to the power values in the community power spectrum table, the inverter frequency is proportionally adjusted downwards to reach the power peak before deceleration; after the power peak is crossed, the frequency is increased in the same way to reach the power valley before acceleration. Finally, the peak and valley power values of the bus system level off and further learn to reach the set impulse; ultimately, a stable impulse is formed. In laboratory testing and field application in the Shengli Oilfield XIN-11 block, the group control software module effectively suppressed the active power peak and valley values and voltage fluctuations of the bus system, the active power fluctuation rate range decreased by more than 70%, and the DC bus voltage fluctuation range decreased by more than 80%; moreover, the active power decreased by approximately 6% without additional hardware costs.
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It is usually believed that differentiated thyroid cancer is less likely to have distant metastases and rarely occurs secondary to hyperthyroidism. In our case report, we describe a patient diagnosed with thyroid fetal adenoma in 2002 who subsequently presented with a painful lump in her right rib. Through puncture biopsy, the mass was considered as metastatic follicular thyroid carcinoma, and then she appeared to have hyperthyroidism. The results of SPECT examination and other tests suggested that the hyperthyroidism was secondary to the thyroid cancer. The patient further underwent total thyroidectomy, and the pathology did not find any follicular thyroid foci. In this article, we analyze and discuss this case and review the relevant literature.
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Ammonia, a vital component in the synthesis of fertilizers, plastics, and explosives, is traditionally produced via the energy-intensive and environmentally detrimental Haber-Bosch process. Given its considerable energy consumption and significant greenhouse gas emissions, there is a growing shift toward electrocatalytic ammonia synthesis as an eco-friendly alternative. However, developing efficient electrocatalysts capable of achieving high selectivity, Faraday efficiency, and yield under ambient conditions remains a significant challenge. This review delves into the decades-long research into electrocatalytic ammonia synthesis, highlighting the evolution of fundamental principles, theoretical descriptors, and reaction mechanisms. An in-depth analysis of the nitrogen reduction reaction (NRR) and nitrate reduction reaction (NitRR) is provided, with a focus on their electrocatalysts. Additionally, the theories behind electrocatalyst design for ammonia synthesis are examined, including the Gibbs free energy approach, Sabatier principle, d-band center theory, and orbital spin states. The review culminates in a comprehensive overview of the current challenges and prospective future directions in electrocatalyst development for NRR and NitRR, paving the way for more sustainable methods of ammonia production.
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Hydrothermal carbonization is an efficient technique for the disposal of livestock manure, enabling its harmless treatment, quantity reduction, and resourceful utilization. Co-hydrothermal of modified materials facilitates the production of more valuable carbonaceous materials. However, further exploration is needed to understand their potential impact on the environmental risks associated with livestock manure disposal and the application of products derived from it. Therefore, the carbonization degree, heavy metals stabilization, and phosphorus retention during the hydrothermal treatment of swine manure were systematically investigated in this study under the influence of in-situ formed MgFe2O4. The results revealed that the in-situ formation of MgFe2O4 improved the dehydration and decarboxylation of organic components in swine manure, thereby improving its carbonization degree. Furthermore, both hydrothermal carbonization and MgFe2O4 modified hydrothermal carbonization resulted in an enhanced stabilization of heavy metals, leading to a significant reduction in their soluble/exchangeable fraction and reducible fraction. Phosphorus was predominantly retained in the hydrochars, with the highest retention rate reaching 88%, attributed to the significant decrease in soluble and exchangeable phosphorus fractions facilitated by the in-situ formation of MgFe2O4. Moreover, MgFe2O4 modified hydrochars exhibited remarkable adsorption capacity for Pb(II) and Cu(II) without any leaching of heavy metals. Overall, the findings indicated that the in-situ formation of MgFe2O4 positively influenced the hydrothermal of swine manure, improving certain economic benefits in its practical application.
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Metais Pesados , Fósforo , Animais , Suínos , Carbono , EstercoRESUMO
Circular mRNA (cmRNA) is particular useful due to its high resistance to degradation by exonucleases, resulting in greater stability and protein expression compared to linear mRNA. T cell receptor (TCR)-engineered T cells (TCR-T) represent a promising means of treating viral infections and cancer. This study aimed to evaluate the feasibility and efficacy of cmRNA in antigen-specific-TCR discovery and TCR-T therapy. Using human cytomegalovirus (CMV) pp65 antigen as a model, we found that the expansion of pp65-responsive T cells was induced more effectively by monocyte-derived dendritic cells transfected with pp65-encoding cmRNA compared with linear mRNA. Subsequently, we developed cmRNA-transduced pp65-TCR-T (cm-pp65-TCR-T) that specifically targets the CMV-pp65 epitope. Our results showed that pp65-TCR could be expressed on primary T cells for more than 7 days. Moreover, both in vitro killing and in vivo CDX models demonstrated that cm-pp65-TCR-T cells specifically and persistently kill pp65-and HLA-expressing tumor cells, significantly prolonging the survival of mice. Collectively, our results demonstrated that cmRNA can be used as a more effective technical approach for antigen-specific TCR isolation and identification, and cm-pp65-TCR-T may provide a safe, non-viral, non-integrated therapeutic approach for controlling CMV infection, particularly in patients who have undergone allogeneic hematopoietic stem cell transplantation.
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Infecções por Citomegalovirus , Transplante de Células-Tronco Hematopoéticas , Humanos , Animais , Camundongos , Infecções por Citomegalovirus/genética , Infecções por Citomegalovirus/terapia , Citomegalovirus/genética , Linfócitos T , Receptores de Antígenos de Linfócitos T/genética , Proteínas da Matriz Viral/genéticaRESUMO
Inflammatory bowel diseases (IBDs), including Crohn's disease and ulcerative colitis, are chronic relapsing inflammatory gastrointestinal tract diseases of uncertain origin, which are frequently associated with zinc deficiency. Animal models have a considerable value in elucidating the process of IBD. In this study, 50 male C57BL/6 J mice were randomly assigned to five groups: control group (Con), 2,4,6-trinitrobenzenesulfonic acid (TNBS) group, and three zinc supplementation groups, namely 160 ppm group, 400 ppm group, and 1000 ppm group. The results showed that supplementation of dietary zinc with zinc oxide could effectively relieve the severity of ulcerative colitis induced by TNBS in mice. We demonstrate that the protective mechanism involves the immunomodulation of dietary zinc by increasing CD3+, CD3+CD8+, and Th2 cells, suppressing Th1 and Th17 cells, and decreasing the production of serum IL-1ß and IL-18. The dietary zinc oxide seems to be able to suppress the NF-κB/NLRP3 signaling pathway by downregulating the mRNA and protein expression of NIK, IKK, NF-κB, and NLRP3. The results suggest that dietary supplementation of zinc oxide may protect against colitis, and proper daily zinc supplementation may reduce the risk of IBD.
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Colite Ulcerativa , Colite , Doenças Inflamatórias Intestinais , Óxido de Zinco , Camundongos , Masculino , Animais , NF-kappa B/metabolismo , Proteína 3 que Contém Domínio de Pirina da Família NLR , Células Th17/metabolismo , Óxido de Zinco/farmacologia , Camundongos Endogâmicos C57BL , Colite/induzido quimicamente , Colite/tratamento farmacológico , Colite/prevenção & controle , Transdução de Sinais , Zinco/efeitos adversos , Modelos Animais de DoençasRESUMO
Fully optical artificial synapses are crucial hardware for neuromorphic computing, which is very promising to address the future large-scale computing capacity problem. The key characteristic required in a semiconductor device to emulate synaptic potentiation and depression in a fully optical artificial synapse is the bidirectional photoresponse. This work integrates wide-band-gap TiO2 polycrystals and narrow-band-gap PbS quantum dots into a graphene transistor simultaneously, providing the device with both near-ultraviolet and near-infrared photoresponses through the photogating effect. Moreover, the TiO2 serves as a hole-trapping matrix and the PbS as an electron-trapping matrix, which impose opposite effects to the device after photoexcitation, resulting in a photoresponse in the opposite polarity. As a result, the device demonstrates a wavelength-dependent bidirectional photoresponse, which enables it to be utilized as a fully optical artificial synapse. By using near-ultraviolet or near-infrared lights as stimuli, the device successfully mimics synaptic plasticity, including synaptic potentiation/depression, paired-pulse facilitation, and spike-rating-dependent plasticity, as well as the human brain-like transition of short-term memory and long-term memory and learning-experience behavior. This work validates the methodology of combining different trap matrices to achieve the bidirectional photoresponse, which can significantly inspire future research in fully optical artificial synapses.
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Lipid nanoparticles (LNPs) have demonstrated efficacy and safety for mRNA vaccine administration by intramuscular injection; however, the pulmonary delivery of mRNA encapsulated LNPs remains challenging. The atomization process of LNPs will cause shear stress due to dispersed air, air jets, ultrasonication, vibrating mesh etc., leading to the agglomeration or leakage of LNPs, which can be detrimental to transcellular transport and endosomal escape. In this study, the LNP formulation, atomization methods and buffer system were optimized to maintain the LNP stability and mRNA efficiency during the atomization process. Firstly, a suitable LNP formulation for atomization was optimized based on the in vitro results, and the optimized LNP formulation was AX4, DSPC, cholesterol and DMG-PEG2K at a 35/16/46.5/2.5 (%) molar ratio. Subsequently, different atomization methods were compared to find the most suitable method to deliver mRNA-LNP solution. Soft mist inhaler (SMI) was found to be the best for pulmonary delivery of mRNA encapsulated LNPs. The physico-chemical properties such as size and entrapment efficiency (EE) of the LNPs were further improved by adjusting the buffer system with trehalose. Lastly, the in vivo fluorescence imaging of mice demonstrated that SMI with proper LNPs design and buffer system hold promise for inhaled mRNA-LNP therapies.
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Lipídeos , Nanopartículas , Camundongos , Animais , Lipídeos/química , RNA Mensageiro , Lipossomos , Endossomos , Nanopartículas/química , RNA Interferente PequenoRESUMO
Dysregulation of long noncoding RNAs (lncRNAs) has been associated with the development and progression of many human cancers. Lactate dehydrogenase A (LDHA) enzymatic activity is also crucial for cancer development, including the development of papillary thyroid cancer (PTC). However, whether specific lncRNAs can regulate LDHA activity during cancer progression remains unclear. Through screening, we identified an LDHA-interacting lncRNA, GLTC, which is required for the increased aerobic glycolysis and cell viability in PTC. GLTC was significantly upregulated in PTC tissues compared with nontumour thyroid tissues. High expression of GLTC was correlated with more extensive distant metastasis, a larger tumour size, and poorer prognosis. Mass spectrometry revealed that GLTC, as a binding partner of LDHA, promotes the succinylation of LDHA at lysine 155 (K155) via competitive inhibition of the interaction between SIRT5 and LDHA, thereby promoting LDHA enzymatic activity. Overexpression of the succinylation mimetic LDHAK155E mutant restored glycolytic metabolism and cell viability in cells in which metabolic reprogramming and cell viability were ceased due to GLTC depletion. Interestingly, GLTC inhibition abrogated the effects of K155-succinylated LDHA on radioiodine (RAI) resistance in vitro and in vivo. Taken together, our results indicate that GLTC plays an oncogenic role and is an attractive target for RAI sensitisation in PTC treatment.
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RNA Longo não Codificante , Neoplasias da Glândula Tireoide , Humanos , Câncer Papilífero da Tireoide/genética , Câncer Papilífero da Tireoide/metabolismo , Câncer Papilífero da Tireoide/patologia , Lactato Desidrogenase 5/genética , Lactato Desidrogenase 5/metabolismo , RNA Longo não Codificante/genética , RNA Longo não Codificante/metabolismo , Radioisótopos do Iodo/metabolismo , Linhagem Celular Tumoral , Neoplasias da Glândula Tireoide/metabolismo , Regulação Neoplásica da Expressão Gênica , Proliferação de Células/genéticaRESUMO
Based on the monthly monitoring of Bao'an Lake in Hubei Province from 2018 to 2020, the eutrophication level of Bao'an Lake in the middle reaches of the Yangtze River is investigated using the comprehensive trophic level index (TLI), chromophoric dissolved organic matter (CDOM) absorption coefficient, and the phytoplankton water quality biological method. The influencing factors are then identified. The results demonstrate that the overall water quality of Bao'an Lake remained at levels III-V during 2018-2020. Due to different eutrophication assessment methods, the results are different, but all show that Bao'an Lake is in a eutrophication state as a whole. The eutrophication level of Bao'an Lake is observed to vary with time, exhibiting an increasing then decreasing trend between 2018-2020, while levels are high in summer and autumn, and low in winter and spring. Moreover, the eutrophication level of Bao'an Lake presents an obviously varying spatial distribution. Potamogeton crispus is the dominant species of the Bao'an Lake, the water quality is good in spring when Potamogeton crispus vigorously grows, but poor in summer and autumn. The permanganate index (CODMn) and total phosphorous (TP), total nitrogen (TN), and chlorophyll a (Chl-a) contents are identified as the main influencing factors of the eutrophication level of Bao'an Lake, with a significant relationship observed between Chl-a and TP (p < 0.01). The above results provide a solid theoretical basis for the ecological restoration of Bao'an Lake.
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Lagos , Rios , Clorofila A , Monitoramento Ambiental/métodos , Qualidade da Água , Eutrofização , Fósforo/análise , Nitrogênio/análise , ChinaRESUMO
Tropical forests are biologically diverse and structurally complex ecosystems that can store a large quantity of carbon and support a great variety of plant and animal species. However, tropical forest structure can vary dramatically within seemingly homogeneous landscapes due to subtle changes in topography, soil fertility, species composition and past disturbances. Although numerous studies have reported the effects of field-based stand structure attributes on aboveground biomass (AGB) in tropical forests, the relative effects and contributions of UAV LiDAR-based canopy structure and ground-based stand structural attributes in shaping AGB remain unclear. Here, we hypothesize that mean top-of-canopy height (TCH) enhances AGB directly and indirectly via species richness and horizontal stand structural attributes, but these positive relationships are stronger at a larger spatial scale. We used a combined approach of field inventory and LiDAR-based remote sensing to explore how stand structural attributes (stem abundance, size variation and TCH) and tree species richness affect AGB along an elevational gradient in tropical forests at two spatial scales, i.e., 20 m × 20 m (small scale), and 50 m × 50 m (large scale) in southwest China. Specifically, we used structural equation models to test the proposed hypothesis. We found that TCH, stem size variation and abundance were strongly positively associated with AGB at both spatial scales, in addition to which increasing TCH led to greater AGB indirectly through increased stem size variation. Species richness had negative to negligible influences on AGB, but species richness increased with increasing stem abundance at both spatial scales. Our results suggest that light capture and use, modulated by stand structure, are key to promoting high AGB stocks in tropical forests. Thus, we argue that both horizontal and vertical stand structures are important for shaping AGB, but the relative contributions vary across spatial scales in tropical forests. Importantly, our results highlight the importance of including vertical forest stand attributes for predicting AGB and carbon sequestration that underpins human wellbeing.
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The upsurge of new materials that can be used for near-infrared (NIR) photodetectors operated without cooling is crucial. As a novel material with a small bandgap of ≈0.28 eV, the topological crystalline insulator SnTe has attracted considerable attention. Herein, this work demonstrates self-driven NIR photodetectors based on SnTe/Si and SnTe:Si/Si heterostructures. The SnTe/Si heterostructure has a high detectivity D* of 3.3 × 1012 Jones. By Si doping, the SnTe:Si/Si heterostructure reduces the dark current density and increases the photocurrent by ≈1 order of magnitude simultaneously, which improves the detectivity D* by ≈2 orders of magnitude up to 1.59 × 1014 Jones. Further theoretical analysis indicates that the improved device performance may be ascribed to the bulk photovoltaic effect (BPVE), in which doped Si atoms break the inversion symmetry and thus enable the generation of additional photocurrents beyond the heterostructure. In addition, the external quantum efficiency (EQE) measured at room temperature at 850 nm increases by a factor of 7.5 times, from 38.5% to 289%. A high responsivity of 1979 mA W-1 without bias and fast rising time of 8 µs are also observed. The significantly improved photodetection achieved by the Si doping is of great interest and may provide a novel strategy for superior photodetectors.
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Mullite-cordierite ceramic saggar is a necessary consumable material used in the synthesis process of LiCoO2 that is easily eroded during application. In our study, we systematically investigated the characteristics and surface corrosion behavior of waste saggar samples. We divided the cross sections of waste saggar into the attached layer, hardened layer, permeability layer, and matrix layer. Then, we examined the high-temperature solid-state reactions between saggar powder and lithium carbonate or cobalt oxide to identify erosion reactants correlating with an increase in the number of recycled saggars. The results of time-of-flight secondary ion mass spectrometric analysis (TOF-SIMS) prove that the maximum erosion penetration of lithium can reach 2 mm. However, our morphology and elemental distribution analysis results show that the erosion penetration of cobalt was only 200 µm. When enough lithium carbonate reacted, lithium aluminate and lithium silicate were the main phases. Our X-ray computed tomography (X-ray CT) analysis results show that the change in phase volume before and after the reaction, including the generation of oxygen and carbon dioxide gas, led to the internal crack expansion of the material-saggar interface. Our results can contribute to improving saggar and upgrading waste saggar utilization technology.