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Inhibition of autophagy increases the sensitivity of tumor cells to radiotherapy and chemotherapy and improves the therapeutic effect on tumors. Recently, photodynamic therapy (PDT) combined with chemotherapy has been proven to further improve the efficiency of cancer treatment. As such, combining autophagy inhibition with PDT and chemotherapy may represent a potentially effective new strategy for cancer treatment. However, currently widely studied autophagy inhibitors inevitably produce various toxic side effects due to their inherent pharmacological activity. To overcome this constraint, in this study, we designed an ideal multifunctional upconversion nanoplatform, UCNP-Ce6-EPI@mPPA + NIR (MUCEN). Control, UCNP-EPI@mPPA (MUE), UCNP-EPI@mPPA + NIR (MUEN), Ce6-EPI@mPPA (MCE), Ce6-EPI@mPPA + NIR (MCEN), and UCNP-Ce6-EPI@mPPA (MUCE) groups were set up separately as controls. Based on a combination of autophagy inhibition and PDT, the average particle size of MUCEN was 197 nm, which can simultaneously achieve the double encapsulation of chlorine e6 (Ce6) and epirubicin (EPI). In vitro tests revealed that MUCE was efficiently endocytosed by 4T1 cells under near-infrared light irradiation. Further, in vivo tests revealed that MUCE dramatically inhibited tumor growth. Immunohistochemistry results indicated that MUCE efficiently increased the expression of autophagy inhibitors p62 and LC3 in tumor tissues. The synergistic effect of autophagy inhibition and PDT with MUCE exhibited superior tumor suppression, providing an innovative approach to cancer treatment.
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BACKGROUND: Early detection and treatment of colorectal cancer (CRC) is crucial for improving patient survival rates. This study aims to identify signature molecules associated with CRC, which can serve as valuable indicators for clinical hematological screening. METHOD: We have systematically searched the Human Protein Atlas database and the relevant literature for blood protein-coding genes. The CRC dataset from TCGA was used to compare the acquired genes and identify differentially expressed molecules (DEMs). Weighted Gene Co-expression Network Analysis (WGCNA) was employed to identify modules of co-expressed molecules and key molecules within the DEMs. Signature molecules of CRC were then identified from the key molecules using machine learning. These findings were further validated in clinical samples. Finally, Logistic regression was used to create a predictive model that calculated the likelihood of CRC in both healthy individuals and CRC patients. We evaluated the model's sensitivity and specificity using the ROC curve. RESULT: By utilizing the CRC dataset, WGCNA analysis, and machine learning, we successfully identified seven signature molecules associated with CRC from 1478 blood protein-coding genes. These markers include S100A11, INHBA, QSOX2, MET, TGFBI, VEGFA and CD44. Analyzing the CRC dataset showed its potential to effectively discriminate between CRC and normal individuals. The up-regulated expression of these markers suggests the existence of an immune evasion mechanism in CRC patients and is strongly correlated with poor prognosis. CONCLUSION: The combined detection of the seven signature molecules in CRC can significantly enhance diagnostic efficiency and serve as a novel index for hematological screening of CRC.
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BACKGROUND: Patients with Eastern Cooperative Oncology Group performance status (ECOG PS) 2 probably cannot tolerate chemotherapy or other antitumor therapies. Some studies have reported that immunotherapy combined with antiangiogenic therapy is well-tolerated and shows good antitumor activity. However, the efficacy of this combination as a later-line therapy in patients with ECOG PS 2 is unclear. This study evaluated the effectiveness and safety of this combination strategy as third- or further-line therapy in stage IV non-small cell lung cancer (NSCLC) patients with ECOG PS 2. METHODS: In this retrospective study, patients treated with camrelizumab plus antiangiogenic therapy (bevacizumab, anlotinib, or recombinant human endostatin) were included. Objective response rate (ORR), disease control rate (DCR), progression-free survival (PFS), overall survival (OS), quality of life (QOL) assessed by ECOG PS, and safety were analyzed. RESULTS: Between January 10, 2019, and February 28, 2024, a total of 59 patients were included. The ORR was 35.6% (21/59) and the DCR was 86.4%. With a median follow-up of 10.5 months (range: 0.7-23.7), the median PFS was 5.5 months (95% confidence interval [CI]: 3.8-7.3) and the median OS was 10.5 months (95% CI: 11.2-13.6). QOL was improved (≥1 reduction in ECOG PS) in 39 patients (66.1%). The most common Grade 3-4 treatment-related adverse events were hepatic dysfunction (6 [10%]), hypertension (5 [8%]), and hypothyroidism (3 [5%]). There were no treatment-related deaths. CONCLUSIONS: Third- or further-line immunotherapy combined with antiangiogenic therapy is well-tolerated and shows good antitumor activity in stage IV NSCLC patients with ECOG PS 2. Future large-scale prospective studies are required to confirm the clinical benefits of this combination therapy.
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Inibidores da Angiogênese , Protocolos de Quimioterapia Combinada Antineoplásica , Carcinoma Pulmonar de Células não Pequenas , Endostatinas , Imunoterapia , Neoplasias Pulmonares , Estadiamento de Neoplasias , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Inibidores da Angiogênese/uso terapêutico , Inibidores da Angiogênese/efeitos adversos , Anticorpos Monoclonais Humanizados/uso terapêutico , Anticorpos Monoclonais Humanizados/administração & dosagem , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos , Bevacizumab/uso terapêutico , Bevacizumab/administração & dosagem , Carcinoma Pulmonar de Células não Pequenas/tratamento farmacológico , Carcinoma Pulmonar de Células não Pequenas/patologia , Carcinoma Pulmonar de Células não Pequenas/mortalidade , Carcinoma Pulmonar de Células não Pequenas/terapia , Endostatinas/uso terapêutico , Endostatinas/administração & dosagem , Imunoterapia/métodos , Indóis/uso terapêutico , Neoplasias Pulmonares/tratamento farmacológico , Neoplasias Pulmonares/patologia , Neoplasias Pulmonares/mortalidade , Neoplasias Pulmonares/terapia , Qualidade de Vida , Quinolinas/uso terapêutico , Estudos RetrospectivosRESUMO
The study aimed to investigate the alleviation of an ethanol-induced gastric ulcer in mice by apolysaccharide (PSP) from purple sweet potato (Ipomoea batatas (L.) Lam) and explore the mechanism. The anti-ulcer activity was determined by histopathological evaluation, total gastric acidity, pepsin activity, gastric ulcer index and gastric ulcer inhibition rate. The expression levels of inflammatory factors were detected using ELISA. A special protein meter was used to detect the content of immunoglobulin lgM, immunoglobulin lgG, and complements C3 and C4 in the serum of mice. The expression of CD4+/CD8+ lymphocyte subsets of mice was detected using flow cytometry. Western blot analysis was used to examine the effect of PSP on the PI3K/Akt/Rheb/mTOR pathway. The results showed that PSP could effectively reduce the total gastric acidity, pepsin activity, and the index and inhibition rate of gastric ulcers. At the same time, PSP could significantly increase the levels of immunoglobulins (lgG and lgM) and complements (C3 and C4). It could also increase the activity of peritoneal macrophages in mice and the expression of CD4+/CD8+ in the spleen. ELISA analysis showed that the contents of TNF-α, IL-1ß and IL-6 were significantly decreased and the content of IL-10 was significantly increased in the PSP group. The western blot analysis showed that PSP could upregulate the relative protein expressions of MUC5AC, PI3K, p-Akt, Rheb and mTOR. These results indicate that PSP can activate the PI3K/Akt/Rheb/mTOR signaling pathway to improve the immunity of mice and maintain the balance of the immune system, thereby protecting the gastric mucosa and improving stress gastric ulcers.
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Ipomoea batatas , Polissacarídeos , Transdução de Sinais , Úlcera Gástrica , Animais , Humanos , Masculino , Camundongos , Antiulcerosos/farmacologia , Etanol , Ipomoea batatas/química , Fosfatidilinositol 3-Quinases/metabolismo , Extratos Vegetais/farmacologia , Polissacarídeos/farmacologia , Proteínas Proto-Oncogênicas c-akt/metabolismo , Transdução de Sinais/efeitos dos fármacos , Úlcera Gástrica/tratamento farmacológico , Úlcera Gástrica/induzido quimicamente , Úlcera Gástrica/imunologia , Serina-Treonina Quinases TOR/metabolismoRESUMO
Latent Low-Rank Representation (LatLRR) has emerged as a prominent approach for fusing visible and infrared images. In this approach, images are decomposed into three fundamental components: the base part, salient part, and sparse part. The aim is to blend the base and salient features to reconstruct images accurately. However, existing methods often focus more on combining the base and salient parts, neglecting the importance of the sparse component, whereas we advocate for the comprehensive inclusion of all three parts generated from LatLRR image decomposition into the image fusion process, a novel proposition introduced in this study. Moreover, the effective integration of Convolutional Neural Network (CNN) technology with LatLRR remains challenging, particularly after the inclusion of sparse parts. This study utilizes fusion strategies involving weighted average, summation, VGG19, and ResNet50 in various combinations to analyze the fusion performance following the introduction of sparse parts. The research findings show a significant enhancement in fusion performance achieved through the inclusion of sparse parts in the fusion process. The suggested fusion strategy involves employing deep learning techniques for fusing both base parts and sparse parts while utilizing a summation strategy for the fusion of salient parts. The findings improve the performance of LatLRR-based methods and offer valuable insights for enhancement, leading to advancements in the field of image fusion.
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In this study, the transmittance of tanshinone â ¡_A(Tan â ¡_A) and cryptotanshinone(CTS) through the blood-prostate barrier and their distributions in the prostate tissue were compared between tanshinone extract(Tan E) treatment group and the corresponding monomer composition group under the equivalent dose conversion in vitro and in vivo. First, the human prostate epithelial cell line RWPE-1 was cultured in vitro for 21 days for the establishment of a blood-prostate barrier model, and the transmission of Tan â ¡_A and CTS through the barrier model was investigated after administration of Tan E and corresponding single active components. Second, SD rats were administrated with 700 mg·kg~(-1) Tan E, 29 mg·kg~(-1) CTS, and 50 mg·kg~(-1) Tan â ¡_A by gavage, and plasma and prostate tissue samples were collected at the time points of 2, 4, 8, 12, and 24 h. The Tan â ¡_A and CTS concentrations in the samples were determined. The results showed that in the cell model, the cumulative transmission amounts of CTS and Tan â ¡_A in the extract at each time point were higher than those of the corresponding single active components(P<0.01). In rats, after the administration of Tan E, the concentrations of Tan â ¡_A and CTS in rat plasma and prostate were higher than those of the corresponding single active components. This study demonstrated that the coexisting components in Tan E promoted the penetration of its main pharmacological components Tan â ¡_A and CTS through the blood-prostate barrier. The findings provide a theoretical and experimental basis for the application of Tan E in the clinical treatment of prostate-related diseases.
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Abietanos , Próstata , Masculino , Ratos , Humanos , Animais , Ratos Sprague-Dawley , Abietanos/farmacologia , PermeabilidadeRESUMO
Hepatocellular carcinoma (HCC) is a highly prevalent and lethal tumor worldwide and its late discovery and lack of effective specific therapeutic agents necessitate further research into its pathogenesis and treatment. Organoids, a novel model that closely resembles native tumor tissue and can be cultured in vitro, have garnered significant interest in recent years, with numerous reports on the development of organoid models for liver cancer. In this study, we have successfully optimized the procedure and established a culture protocol that enables the formation of larger-sized HCC organoids with stable passaging and culture conditions. We have comprehensively outlined each step of the procedure, covering the entire process of HCC tissue dissociation, organoid plating, culture, passaging, cryopreservation, and resuscitation, and provided detailed precautions in this paper. These organoids exhibit genetic similarity to the original HCC tissues and can be utilized for diverse applications, including the identification of potential therapeutic targets for tumors and subsequent drug development.
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Carcinoma Hepatocelular , Neoplasias Hepáticas , Humanos , Carcinoma Hepatocelular/tratamento farmacológico , Carcinoma Hepatocelular/genética , Neoplasias Hepáticas/tratamento farmacológico , Neoplasias Hepáticas/genética , Descoberta de Drogas , Desenvolvimento de Medicamentos , OrganoidesRESUMO
The Adoxophyes tea tortrix (Lepidoptera: Tortricidae) is a group of leaf rollers that cause enormous economic losses on tea and apple crops. In East Asia, taxonomic ambiguity of the Adoxophyes orana complex (AOC), which consists of A. orana, A. dubia, A. honmai, and A. paraorana, has persisted for decades because of vague diagnostic characters. In this study, differences in the AOC were examined to improve species identification, determine genetic variations, and develop control strategies. Analyses revealed that A. orana comprised 2 lineages, a widely distributed Palearctic lineage and an East Asian lineage that was nested with other Asian species. Genetic divergence of >3% is proposed to confirm the AOC species that would benefit subsequent taxonomic revision. The monophyletic Taiwanese A. sp. with 2.8-4% from other AOC species appeared to suggest it as an independent taxon, and low interspecific divergence between A. honmai and A. dubia of 0.3% indicated possibility of recent divergence or intraspecific variations. Our result further suggested that the Z9-14:Ac ratio of semiochemicals could be a reference for the reblending of pheromone attractants in Taiwanese tea plantations. Moreover, the AOC species appeared to have a tendency of specific geographic distributions, with A. dubia and A. honmai in Japan and China, A. paraorana in Korea, and A. sp. in Taiwan. Maintaining the unique genetic composition of Adoxophyes species in each geographic region and preventing the possible invasions into those AOC-free countries through the transportation of host plants are essential in managing the AOC in East Asia.
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PURPOSE: Circular RNAs (circRNAs) are recently identified as a class of non-coding RNAs that participate in the incidence of acute myocardial infarction (AMI). However, circRNAs expression pattern in obstructive sleep apnea (OSA) with AMI remains unknown. The aim was to investigate circRNAs expression alteration in serum exosomes derived from OSA patients with AMI. METHODS: The serum exosomal circRNAs profile of three healthy subjects, three OSA without AMI and three OSA with AMI were analyzed using high-throughput sequencing. Bioinformatic analyses were carried out to assess potential core circRNAs and functional analyses were conducted to study biological functions. RESULTS: Compared to healthy subjects, there were 5225 upregulated and 5798 downregulated circRNAs in exosomes from OSA with AMI patients. And our study also identified 5210 upregulated and 5813 downregulated circRNAs in OSA with AMI patients compared to OSA without AMI. The differential expression of 2 circRNAs (hsa_circRNA_101147, hsa_circRNA_101561) between healthy subjects and OSA without AMI, and 4 circRNAs (hsa_circRNA_101328, hsa_circRNA_104172, hsa_circRNA_104640, hsa_circRNA_104642) between healthy subjects and OSA with AMI were confirmed by qRT-PCR. In addition, we demonstrated that miR-29a-3p targeted hsa_circRNA_104642 directly. CONCLUSIONS: This study demonstrated that there were a number of dysregulated circRNAs in exosomes from OSA with AMI patients, which might be effectively served as a promising diagnostic biomarker and therapeutic targets.
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RNA Circular , RNA , Humanos , RNA Circular/genética , RNA Circular/metabolismo , RNA/metabolismoRESUMO
Although many machine learning methods have been widely used to predict PM2.5 concentrations, these single or hybrid methods still have some shortcomings. This study integrated the advantages of convolutional neural network (CNN) feature extraction and the regression ability of random forest (RF) to propose a novel CNN-RF ensemble framework for PM2.5 concentration modeling. The observational data from 13 monitoring stations in Kaohsiung in 2021 were selected for model training and testing. First, CNN was implemented to extract key meteorological and pollution data. Subsequently, the RF algorithm was employed to train the model with five input factors, namely the extracted features from the CNN and spatiotemporal factors, including the day of the year, the hour of the day, latitude, and longitude. Independent observations from two stations were used to evaluate the models. The findings demonstrated that the proposed CNN-RF model had better modeling capability compared with the independent CNN and RF models: the average improvements in root mean square error (RMSE) and mean absolute error (MAE) ranged from 8.10% to 11.11%, respectively. In addition, the proposed CNN-RF hybrid model has fewer excess residuals at thresholds of 10 µg/m3, 20 µg/m3, and 30 µg/m3. The results revealed that the proposed CNN-RF ensemble framework is a stable, reliable, and accurate method that can generate superior results compared with the single CNN and RF methods. The proposed method could be a valuable reference for readers and may inspire researchers to develop even more effective methods for air pollution modeling. This research has important implications for air pollution research, data analysis, model estimation, and machine learning.
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Poluição do Ar , Redes Neurais de Computação , Poluição do Ar/análise , Aprendizado de Máquina , Algoritmo Florestas Aleatórias , Material Particulado/análiseRESUMO
The self-assembly of the high-nuclearity Ln-exclusive nanoclusters is challenging but of significance due to its aesthetically pleasing architectures and far-reaching latent applications in magnetic cooling technologies. Herein, two novel high-nuclearity lanthanide nanoclusters were successfully synthesized under solvothermal conditions, formulated as {[Gd18(IN)20(HCOO)8(µ6-O)(µ3-OH)24(H2O)4]·4H2O}n and {[Eu18(IN)16(HCOO)8(CH3COO)4(µ6-O)(µ3-OH)24(H2O)4]·5H2O}n (abbreviated as Gd18 and Eu18, HIN = isonicotinic acid). Both of them possess novel and exquisite windmill-shaped cationic cores in the family of high-nuclearity Ln-exclusive nanoclusters. Remarkably, the adjacent second building units are interconnected into a three-dimensional (3D) metal-organic framework by IN- ligands. As expected, the abundant existence of GdIII ions endows Gd18 with a favorable magnetic entropy change at 2.0 K for ΔH = 7.0 T (-ΔSmmax = 40.0 J kg-1 K-1), and Eu18 displays the typical luminescence of EuIII ions.
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BACKGROUND: Maize productivity in semi-arid regions is increasingly at risk because of the sparse and uneven precipitation, and it is also restricted by excessive or insufficient fertilization management strategies. A 4-year (2016-2019) field experiment was therefore conducted to show the effects of fertilizer with five nitrogen levels (0, 75-90, 150-180, 270, and 360 kg ha-1 , represented as N0 , N75-90 , N150-180 , N270 , N360 , respectively) under two variable precipitation patterns (rainy at pre-anthesis in 2016 and 2018 versus dry at pre-anthesis in 2017 and 2019) on soil water storage (SWS), water use efficiency (WUE), nitrogen use efficiency (NUE), and maize yield in the Loess Plateau. RESULTS: Nitrogen inputs increased the amount of above-ground dry matter and the WUE for dry matter (WUEd). Dry years at pre-anthesis significantly reduced dry matter accumulation and kernel number per plant. However, soil water storage before sowing (SWSs) decreased from 440 mm in 2016 to 384 mm in 2019, and the increase in fertilization resulted in the water imbalance. Both the maximum grain yield and WUE for grain yield were found in N270 under rainy years at pre-anthesis, whereas in N150-180 under dry years at pre-anthesis. The average nitrogen recovery efficiency (NRE), nitrogen agronomy efficiency (NAE) and nitrogen partial factor productivity (NPFP) decreased with increases in N application, compared with N360 , the NRE,NAE and NPFP of N150-180 increased by 63.5%, 189.2% and 135.5%, respectively. CONCLUSIONS: Reducing basal N fertilizers could enhance maize yield and maintain moderate water and nitrogen productivity in years with less rainfall. © 2023 Society of Chemical Industry.
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Nitrogênio , Zea mays , Nitrogênio/análise , Água , Agricultura/métodos , Solo , Fertilizantes , ChinaRESUMO
Ferroptosis, a type of programmed cell death induced by the iron-dependent lipid hydroperoxide pathway, has attracted widespread attention. However, Fenton response-dependent ferroptosis has many limitations, such as insufficient reaction conditions in the tumor micro-environment. Here, we propose an all-in-one phototherapy nanoplatform consisting of iron-polydopamine (Fe-PDA), a folic acid-modified red blood cell membrane (FA-RBCm), and epirubicin (EPI), namely, Fe-PDA-EPI@FA-RBCm NPs, to achieve enhanced photothermal-ferroptosis effects via overcoming the limitations of the Fenton-like reaction. The results showed that the synthesized biomimetic nanoparticles could decompose hydrogen peroxide (H2O2) to generate hydroxyl radicals (ËOH), and further induce the non-apoptotic ferroptosis pathway. After irradiation with near-infrared (NIR) light, the uptake of Fe-PDA-EPI@FA-RBCm NPs by cells could be effectively promoted, and it presented impressive in vitro and in vivo photothermal properties. In vitro and in vivo results showed that laser irradiation could enhance ferroptosis by promoting the production of reactive oxygen species (ROS) and lipid peroxides, down-regulating the expression of glutathione peroxidase 4 (GPX4), and reducing the mitochondrial membrane potential. Furthermore, the photothermal-promoted ferroptosis and apoptosis pathways (photothermal therapy and chemotherapy) exhibited outstanding synergistic antitumor efficacy in vitro and in vivo, with an in vivo tumor inhibition rate as high as 76.95%. In conclusion, the construction of tumor-targeted biomimetic nanocarriers utilizing the advantageous properties of RBCm has been investigated as a potential anticancer strategy.
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Ferroptose , Nanopartículas , Neoplasias , Peróxido de Hidrogênio/farmacologia , Nanopartículas/uso terapêutico , Apoptose , Epirubicina/farmacologia , Ferro/farmacologiaRESUMO
PURPOSE: Patients with obstructive sleep apnoea (OSA) have a high incidence of vascular endothelial injury. The most important pathophysiological feature of OSA is chronic intermittent hypoxia (CIH). This study aimed to investigate the mechanisms of CIH-related vascular endothelial injury. METHODS: IH exposure was applied to human umbilical vein endothelial cells (HUVECs). After modeling, cell viability, the expression levels of peroxisome proliferator activated receptor γ (PPARγ), apoptosis-associated proteins and mitochondrial division fusion proteins, and the levels of reactive oxygen species (ROS) and mitochondrial membrane potential (MMP) were assessed via Cell Counting Kit-8 (CCK-8), western blotting, fluorescent microscope, and flow cytometry, respectively. Rosiglitazone (PPARγ agonist), tempo (the mitochondrial-specific antioxidant), and tempo combined with PPARγ interfering RNA were used to treat HUVECs, respectively. RESULTS: After IH exposure, cell viability and levels of MMP decreased, cell apoptosis and ROS levels increased, and the expression levels of PPARγ decreased. Both tempo and rosiglitazone pretreatment ameliorated cell apoptosis and improved cell viability. In addition, mitochondrial function became better after tempo pretreatment. PPARγ interference reversed the protective effects of tempo on IH-related mitochondrial function injury and cell injury. CONCLUSIONS: PPARγ regulated the apoptosis and cell viability of IH-treated HUVECs by altering mitochondrial function. This finding clarifies the mechanism of CIH-related vascular endothelial injury.
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PPAR gama , Apneia Obstrutiva do Sono , Humanos , Células Endoteliais da Veia Umbilical Humana/metabolismo , PPAR gama/genética , Espécies Reativas de Oxigênio/metabolismo , Rosiglitazona/farmacologia , Rosiglitazona/metabolismo , Hipóxia/metabolismo , Apneia Obstrutiva do Sono/metabolismo , ApoptoseRESUMO
With the continual advancement of positioning technology, people's use of mobile devices has increased substantially. The global navigation satellite system (GNSS) has improved outdoor positioning performance. However, it cannot effectively locate indoor users owing to signal masking effects. Common indoor positioning technologies include radio frequencies, image visions, and pedestrian dead reckoning. However, the advantages and disadvantages of each technology prevent a single indoor positioning technology from solving problems related to various environmental factors. In this study, a hybrid method was proposed to improve the accuracy of indoor positioning by combining visual simultaneous localization and mapping (VSLAM) with a magnetic fingerprint map. A smartphone was used as an experimental device, and a built-in camera and magnetic sensor were used to collect data on the characteristics of the indoor environment and to determine the effect of the magnetic field on the building structure. First, through the use of a preestablished indoor magnetic fingerprint map, the initial position was obtained using the weighted k-nearest neighbor matching method. Subsequently, combined with the VSLAM, the Oriented FAST and Rotated BRIEF (ORB) feature was used to calculate the indoor coordinates of a user. Finally, the optimal user's position was determined by employing loose coupling and coordinate constraints from a magnetic fingerprint map. The findings indicated that the indoor positioning accuracy could reach 0.5 to 0.7 m and that different brands and models of mobile devices could achieve the same accuracy.
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Campos Magnéticos , Pedestres , Humanos , Fenômenos Físicos , Análise por Conglomerados , Computadores de MãoRESUMO
Objective: The purpose of this study was to analyze the stability and instrument-related complications associated with fixation of the lumbar spine using the Short-Rod (SR) technique. Methods: Using finite element analysis, this study assessed the stability of a bilateral lumbar fixation system when inserting the pedicle screws at angles of 10°, 15°, and 20° to the endplate in the sagittal plane. Using the most stable construct with a screw angle, the model was then assessed with different rod lengths of 25, 30, 35, and 45 mm. The optimal screw inclination angle and rod length were incorporated into the SR model and compared against traditional parallel screw insertion (pedicle screws in parallel to the endplate, PPS) in terms of the stability and risk of instrument-related complications. The following parameters were evaluated using the validated L4-L5 lumbar finite element model: axial stiffness, range of motion (ROM), stress on the endplate and facet joint, von-Mises stress on the contact surface between the screw and rod (CSSR), and screw displacement. Results: The results showed that the SR model with a 15° screw inclination angle and 35 mm rod length was superior in terms of construct stability and risk of complications. Compared to the PPS model, the SR model had lower stiffness, lower ROM, less screw displacement, and lower stress on the facet cartilage, the CSSR, and screws. However, the SR model also suffered more stress on the endplate in flexion and lateral bending. Conclusion: The SR technique with a 15° screw inclination and 35 mm rod length offers good lumbar stability with a low risk of instrument-related complications.
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Salt stress is one of the major abiotic factors limiting the productivity of bermudagrass (Cynodon dactylon). However, the role of hormonal reprogramming and crosstalk in regulating root growth and salt tolerance in bermudagrass was not reported. Here, we examined the physiological and hormonal responses of two contrasting bermudagrass genotypes; 'C43,' salt-tolerant 'C198' salt-sensitive. Under salt stress, 'C43' had better membrane stability and higher photosynthetic activity than the 'C198.' Salt stress promoted root growth and improved root/shoot ratio and root activity in 'C43,' but the root growth of 'C198' was inhibited by salt stress, leading to diminished root activity. The two bermudagrass genotypes also showed critical differences in hormonal responses, especially in the roots. The root contents of indole-3-acetic acid (IAA), cytokinin derivatives, such as trans-zeatin riboside (tZR) and dihydrozeatin riboside (DHZR) were increased in 'C43,' but decreased in 'C198' when exposed to salt stress. The root growth rate was positively correlated with the root IAA, tZR and DHZR, indicating their crucial role in root growth under salt stress. The expressions of TAA/YUCCA and CYP735A involved in IAA and tZR biosynthesis were induced by salt stress in 'C43,' but inhibited in 'C198,' leading to reduced hormone accumulations. Salt stress decreased the iP, tZ, and DHZ content in the roots of both genotypes, and no significant difference was observed between the two genotypes. Salt stress reduced the content of GA3 in both genotypes by inhibiting GA20ox and GA2ox genes, which could be attributed to the reduced shoot growth in both genotypes. The increased ABA level by salt stress was significantly higher in 'C198' than 'C43.' Furthermore, there were positive and negative correlations between different hormones and root growth, suggesting that root growth could be regulated by complex hormonal reprogramming and crosstalk. This study provides a foundation for understanding the underlying mechanisms of hormonal-mediated root growth and salt tolerance in bermudagrass.
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Assembling and studying high-nuclearity 3d-4f metal clusters represent a pregnant and challenging research hotspot. Based on anionic template and ligand-controlled hydrolytic methods, two heterometallic metal clusters, formulated as [Gd23Ni20(DTA)20(CO3)4(CH3COO)6(SiO4)4(CH3CH2OH)2(µ3-OH)33(µ2-OH)4(H2O)16]·Cl2·30H2O and [Eu23Ni20(DTA)20(CO3)4(CH3COO)6(SiO4)4(CH3CH2OH)2(µ3-OH)33(µ2-OH)4(H2O)16]·Cl2·46H2O (abbreviated as Gd23Ni20, Eu23Ni20, H2DTA = thiodiglycolic acid), are successfully obtained, which both feature similar double-shell-shaped structures with a Ni20 building unit encapsulating a Ln23 aggregation. The structural analysis illustrates that the SiO44- anion, serving as the anionic template in this work, is reported for the second time in 3d-4f metal clusters. In terms of the magnetic properties, large amounts of Gd3+ and Ni2+ ions contribute to the MCE of compound Gd23Ni20, along with 38.15 J kg-1 K-1 at ΔH = 7.0 T for 2.0 K. It is worth mentioning that compound Gd23Ni20 exhibits an excellent magnetic entropy change at low fields (-ΔSm = 19.10 J kg-1 K-1 at 2.0 K for ΔH = 2.0 T). In addition, Gd23Ni20 exhibits preferable solvent and thermal stability.
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The distinct nanosized cluster Gd22Ni21 was isolated using a mixture of anions (SO32- and SO42-) as templates, and to the best of our knowledge, this was the first such 3d-4f cluster to have been developed. Additionally, of a number of 3d-4f heterometallic clusters, Gd22Ni21 showed the largest low-field magnetic entropy change (26.1 J kg-1 K-1) at 2.0 K and ΔH = 2.0 T.