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The increasing accumulation of microplastics (MPs) in agroecosystems has raised significant environmental and public health concerns, facilitating the application of biodegradable plastics. However, the comparative effects of conventional and biodegradable MPs in agroecosystem are still far from fully understood. Here we developed microcosm experiments to reveal the ecological effects of conventional (polyethylene [PE] and polypropylene [PP]) and biodegradable (polyadipate/butylene terephthalate [PBAT] and polycaprolactone [PCL]) MPs (0, 1%, 5%; w/w) in the maize-soil ecosystem. We found that PCL MPs reduced plant production by 73.6-75.2%, while PE, PP and PBAT MPs elicited almost negligible change. The addition of PCL MPs decreased specific enzyme activities critical for soil nutrients cycling by 71.5-95.3%. Biodegradable MPs tended to reduce bacterial α-diversity. The 1% treatments of PE and PBAT, and PCL enhanced bacterial networks complexity, whereas 5% of PE and PBAT, and PP had adverse effect. Moreover, biodegradable MPs appeared to reduce the α-diversity and networks complexity of fungal community. Overall, PCL reduced the ecosystem multifunctionality, mainly by inhibiting the microbial metabolic activity. This study offers evidence that biodegradable MPs can impair agroecosystem multifunctionality, and highlights the potential risks to replace the conventional plastics by biodegradable ones in agricultural practices.
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Ecossistema , Microplásticos , Poluentes do Solo , Zea mays , Zea mays/metabolismo , Microplásticos/toxicidade , Poluentes do Solo/análise , Biodegradação Ambiental , Poliésteres/metabolismo , Plásticos Biodegradáveis , Microbiologia do Solo , Fungos/metabolismo , Bactérias/metabolismo , Solo/química , PolipropilenosRESUMO
OBJECTIVE: To identify recurrent venous thromboembolism (VTE) after discontinuation of anticoagulation in patients with isolated distal deep vein thrombosis based on its anatomic localization (axial or muscular veins). METHODS: Data were sourced from PubMed, Embase, Cochrane Library, Web of Science, and ClinicalTrials.gov databases in the time period up to October 2023. The study followed PRISMA guidelines using a registered protocol (CRD42023443029). Studies reporting recurrent VTE in patients with axial or muscular DVT were included in the analysis. RESULTS: Five studies with a total of 1,403 participants were evaluated. The results showed a pooled odds ratio of 1.12 (95% confidence interval 0.77-1.63) between axial and muscular DVT. Heterogeneity was low (I2 = 0%, p = 0.91) and there was no significant difference in the rate of recurrent VTE between axial and muscular DVT in each subgroup. CONCLUSIONS: Muscular and axial DVT showed comparable recurrent VTE rates after anticoagulation. However, uncertainties regarding the possibility of recurrence affecting the popliteal vein or resulting in pulmonary embolism following muscular DVT anticoagulation persisted. Randomized trials in patients with isolated distal DVT are still needed to clarify its prognosis for different anatomical thrombus locations.
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BACKGROUND: Patients with coronavirus disease 2019 have a high incidence of thrombosis that decreases after recovery. When coronavirus disease 2019 is accompanied by diseases prone to thrombosis, risk of post-infection thrombotic events may increase. CASE PRESENTATION: We report a case of digital ischemic gangrene in a 24-year-old Chinese female with systemic lupus erythematosus after recovery from coronavirus disease 2019. The pathogenesis was related to clinical characteristics of systemic lupus erythematosus, hypercoagulability caused by coronavirus disease 2019, and second-hit due to viral infection. CONCLUSION: Patients with autoimmune diseases should remain alert to autoimmune system disorders induced by severe acute respiratory syndrome coronavirus 2 and other viruses. Treatment for these patients should be strictly standardized, and appropriate anticoagulation methods should be selected to prevent thrombosis.
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COVID-19 , Gangrena , Isquemia , Lúpus Eritematoso Sistêmico , Humanos , Feminino , COVID-19/complicações , Lúpus Eritematoso Sistêmico/complicações , Adulto Jovem , Isquemia/etiologia , Gangrena/etiologia , Dedos/patologia , Dedos/irrigação sanguínea , SARS-CoV-2 , Necrose , Anticoagulantes/uso terapêuticoRESUMO
OBJECTIVE: To compare the predictive efficacy of the PADUA and Caprini models for pulmonary embolism (PE) in gynecological inpatients, analyze the risk factors for PE, and validate whether both models can effectively predict mortality rates. METHODS: A total of 355 gynecological inpatients who underwent computed tomography pulmonary angiography (CTPA) were included in the retrospective analysis. The comparative assessment of the predictive capabilities for PE between the PADUA and Caprini was carried out using receiver operating characteristic (ROC) curves. Logistic regression analysis was used to identify risk factors associated with PE. Additionally, Kaplan-Meier survival analysis plots were generated to validate the predictive efficacy for mortality rates. RESULTS: Among 355 patients, the PADUA and Caprini demonstrated the area under the curve (AUC) values of 0.757 and 0.756, respectively. There was no statistically significant difference in the AUC between the two models (P = 0.9542). Multivariate logistic analysis revealed immobility (P < 0.001), history of venous thromboembolism (VTE) (P = 0.002), thrombophilia (P < 0.001), hormonal treatment (P = 0.022), and obesity (P = 0.019) as independent risk factors for PE. Kaplan-Meier survival analysis demonstrated the reliable predictive efficacy of both the Caprini (P = 0.00051) and PADUA (P = 0.00031) for mortality. ROC for the three- and six-month follow-ups suggested that the Caprini model exhibited superior predictive efficacy for mortality. CONCLUSIONS: The PADUA model can serve as a simple and effective tool for stratifying high-risk gynecological inpatients before undergoing CTPA. The Caprini model demonstrated superior predictive efficacy for mortality rates.
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Purpose: The study investigates the value of the BRAFV600E mutation in determining the aggressiveness of papillary thyroid cancer (PTC) and its correlation with ultrasound features. Methods: The study selected 176 patients with BRAFV600E mutation and 80 without the mutation who underwent surgery at Guangxi Medical University Cancer Hospital. Clinical and pathological data were collected, focusing on BRAFV600E mutations and associated ultrasonic features. Correlation analysis, as well as univariate and multivariate logistic regression analysis, were conducted to identify independent risk factors for BRAFV600E mutation. The results were verified using a nomogram model. Results: The analysis results indicate that the BRAFV600E mutation correlates with tumor size, nodule size, taller-than-wide shape, margin, and shape of papillary thyroid cancer. The receiver operating characteristic curve was used to analyze the diagnostic effect of these features on BRAFV600E mutation. The results showed that nodule size had the most significant area under the curve (AUC = 0.665). Univariate and multivariate logistic regression analyses revealed that taller-than-wide shape ≥1, ill-defined margin, irregular shape, nodule size (≤1.40 cm), TT4 (>98.67 nmol/L), and FT3 (<4.14 pmol/L) were independent risk factors for BRAFV600E mutation. While considering all these factors in the nomogram, the Concordance index (C-index) remained high at 0.764. This suggests that the model has a good predictive effect. Conclusion: Ultrasound features including nodule size, taller-than-wide shape ≥1, ill-defined margins, irregular shape, higher TT4 levels, and lower FT3 levels were associated with papillary thyroid cancer aggressiveness and BRAFV600E mutation.
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OBJECTIVE: This study aimed to compare the efficacy of customized graduated elastic compression stockings (c-GECSs) based on lower leg parameter models with standard GECSs (s-GECSs) in patients with chronic venous disease (CVD). METHODS: In this randomized, single-blind, controlled trial, 79 patients with stage C2 or C3 CVD were assigned to one of two groups: c-GECSs or s-GECSs. The primary outcome was change to Venous Insufficiency Epidemiological and Economic Study Quality of Life (VEINES-QOL) scores at months 1, 3, and 6 as compared with baseline. Secondary outcomes included compliance with wearing ECSs, interface pressure at the smallest circumference of the ankle (point B) and the largest circumference of the calf (point C), and calf volume (CV). RESULTS: There were 13 pairs of s-GECS and 2 pairs of c-GECS that showed pressure values higher than the standard at either point B or C. The c-GECSs were significantly superior to s-GECSs in terms of score improvement at all three time points (month 1, 8.47 [95% confidence interval (CI), 7.47-9.45] vs 5.89 [95% CI, 5.00-6.78]; month 3, 9.60 [95% CI, 8.47-10.72] vs 6.72 [95% CI, 5.62-7.83]; month 6, 7.09 [95% CI, 5.93-8.24] vs 3.92 [95% CI, 2.67-5.18]; P < .0001). Besides, at month 1, the mean daily use time of the c-GECS and s-GECS groups was 10.7 and 9.5 hours, respectively (P < .05). Correlation analysis indicated a negative relationship between local high pressure and daily duration in the s-GECS group (rpb = -0.388; n = 38; P < .05). Variances in pressure were greater in the s-GECSs group. The c-GECSs showed advantage in maintaining pressure. Both c-GECSs and s-GECSs effectively reduced CV (mL), with no significant differences between groups (month 1, 90.0 [95% CI, 71.4-108.5] vs 85.0 [95% CI, 65.6-104.2]; month 3, 93.8 [95% CI, 69.7-117.8] vs 85.9 [95% CI, 65.5-106.2]; month 6, 70.8 [95% CI, 46.5-95.2]) vs 60.8 [95% CI, 44.1-77.5]). CONCLUSIONS: The c-GECSs based on individual leg parameter models significantly improved VEINES-QOL scores and provided stable and enduring pressure as compared with s-GECSs for patients with stage C2 or C3 CVD. Although both c-GECSs and s-GECSs effectively reduced CV, the superior fit and comfort of c-GECSs improved patient compliance. Hence, c-GECSs are a viable alternative for patients who have difficulty tolerating s-GECSs.
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Meias de Compressão , Insuficiência Venosa , Humanos , Qualidade de Vida , Método Simples-Cego , Veias , Insuficiência Venosa/terapia , Doença CrônicaRESUMO
OBJECTIVE: To investigate the incidence of isolated distal deep venous thrombosis (IDDVT) concurrent with pulmonary embolism (PE) in gynecologic inpatients, analyze the risk factors for IDDVT with PE, and establish a nomogram model for IDDVT patients with PE. METHODS: A total of 260 patients were diagnosed with IDDVT between December 2017 and November 2020. The incidence of PE in these patients was determined using computed tomography pulmonary angiography. Logistic regression analysis was used to identify the related risk factors. On this basis, nomogram risk prediction models were established. RESULTS: Among 260 patients with IDDVT, 106 (40.8%) had concurrent PE, of whom 74 (28.5%) experienced silent PE. Univariate logistic analysis demonstrated statistical significance for body mass index (BMI; P = 0.044), glucocorticoid therapy (P = 0.009), hypertension (P < 0.001), and diabetes (P < 0.001). Multivariate logistic analysis revealed that these were independent risk factors for IDDVT with PE that retained statistical significance. A nomogram based on these factors was constructed to predict PE in patients with IDDVT. Its receiver operating characteristic (ROC) showed an area under the curve of 0.710 (95% confidence interval 0.642-0.779), with prediction sensitivity of 64.2% and prediction specificity of 76.6%. CONCLUSIONS: In the present study, a high prevalence of PE was found in gynecologic inpatients with IDDVT. Glucocorticoid therapy, hypertension, diabetes, and BMI were independent risk factors for IDDVT patients with PE. Taking these risk factors into account, a nomogram risk prediction model was developed to help facilitate early detection of concurrent PE.
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Diabetes Mellitus , Hipertensão , Embolia Pulmonar , Trombose Venosa , Humanos , Feminino , Trombose Venosa/diagnóstico por imagem , Trombose Venosa/epidemiologia , Pacientes Internados , Nomogramas , Glucocorticoides , Embolia Pulmonar/diagnóstico por imagem , Embolia Pulmonar/epidemiologia , Embolia Pulmonar/complicações , Fatores de Risco , Hipertensão/complicaçõesRESUMO
Although pervasive microplastics (MPs) pollution in terrestrial ecosystems invites increasing global concern, impact of MPs on soil microbial community assembly and ecosystem multifunctionality received relatively little attention. Here, we manipulated a mesocosm experiment to investigate how polyethylene MPs (PE MPs; 0, 1%, and 5%, w/w) influence ecosystem functions including plant production, soil quality, microbial community diversity and assembly, enzyme activities in carbon (C), nitrogen (N) and phosphorus (P) cycling, and multifunctionality in the maize-soil continuum. Results showed that PE MPs exerted negligible effect on plant biomass (dry weight). The treatment of 5% PE MPs caused declines in the availability of soil water, C and P, whereas enhanced soil pH and C storage. The activity of C-cycling enzymes (α/ß-1, 4-glucosidase and ß-D-cellobiohydrolase) was promoted by 1% PE MPs, while that of ß-1, 4-glucosidase was inhibited by 5% PE MPs. The 5% PE MPs reduced the activity of N-cycling enzymes (protease and urease), whereas increased that of the P-cycling enzyme (alkaline phosphatase). The 5% PE MPs shifted soil microbial community composition, and increased the number of specialist species, microbial community stability and networks resistance. Moreover, PE MPs altered microbial community assembly, with 5% treatment decreasing dispersal limitation proportion (from 13.66% to 9.96%). Overall, ecosystem multifunctionality was improved by 1% concentration, while reduced by 5% concentration of PE MPs. The activity of α/ß-1, 4-glucosidase, urease and protease, and ammonium-N content were the most important predictors of ecosystem multifunctionality. These results underscore that PE MPs can alter soil microbial community assembly and ecosystem multifunctionality, and thus development and implementation of practicable solutions to control soil MPs pollution become increasingly imperative in sustainable agricultural production.
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Microbiota , Microplásticos , Ecossistema , Solo/química , Plásticos , Polietileno , Urease , Microbiologia do Solo , Peptídeo Hidrolases , GlucosidasesRESUMO
Since the enhancement of the photonic spin Hall effect (PSHE) is limited around the Brewster's angle, the scientific problem of how to extend the range of incident angles and to keep them unidirectional for the enhanced PSHE remains open. Here, we propose an effective method to achieve the ultrawide angle and unidirectional enhancement of PSHE via the omnidirectional Brewster's effect in a tilted uniaxial crystal. By properly setting the permittivity and the optical axial angle of the uniaxial crystal, the omnidirectional Brewster's effect can be obtained to realize an ultrawide angle enhancement of the PSHE. Then, by appropriately deviating the optical axial angle, the ultrawide enhancement of the PSHE can be achieved within the maximum incident angle range of 60° with unchanged direction. These findings inspire an unprecedented route to facilitate the applications in precision measurement and spin-dependent devices.
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OBJECTIVE: Compression therapy with the use of graduated compression stockings (GCSs) is a common treatment strategy for chronic venous disease (CVD). However, there is no uniform and objective standard to assess adherence to the use of GCSs. The aim of this study is to develop and validate a GCS Compliance Scale (GCSAS) to fill gaps in internationally recognized comprehensive scales and provide a useful tool for future research. METHODS: The items included in the GCSAS were based on a review of the literature and open-ended interviews with experts, who screened the initial items using an item-level content validity index. Then, pilot tests were conducted three times with 50 participants. After exclusion of redundant and cross-loading items by exploratory factor analysis, 290 subjects were recruited to evaluate the reliability and validity of the proposed GCSAS. Analyses included internal consistency, test-retest reliability, split-half reliability, construct validity, criterion validity, convergent validity, and discriminant validity. RESULTS: The final GCSAS consisted of 17 items and 5 dimensions. The results of the exploratory factor analysis indicated that the variances of each factor explained were 22.03%, 14.85%, 14.74%, 14.16%, and 13.35%, and all 5 factors explained 79.13% of the variance among the 17 items. The factor loadings of all items were >0.7. Confirmatory factor analysis indicated that the indices were adequate. A significant positive correlation was found between the GCSAS and the Venous Insufficiency Epidemiological and Economic Study - Quality of Life questionnaire scores (r = 0.76, p < 0.001). The Cronbach's alpha coefficient was 0.90, test-retest reliability was 0.81, and split-half reliability was 0.92. CONCLUSIONS: The GCSAS showed good validity and reliability to assess compliance with the use of GCSs among patients with CVD.
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Doenças Cardiovasculares , Qualidade de Vida , Humanos , Reprodutibilidade dos Testes , Meias de Compressão , Psicometria/métodos , Inquéritos e Questionários , Doença CrônicaRESUMO
Modeling arbitrarily large deformations of surfaces smoothly embedded in three-dimensional space is challenging. We give a new method to represent surfaces undergoing large spatially varying rotations and strains, based on differential geometry, and surface first and second fundamental forms. Methods that penalize the difference between the current shape and the rest shape produce sharp spikes under large strains, and variational methods produce wiggles, whereas our method naturally supports large strains and rotations without any special treatment. For stable and smooth results, we demonstrate that the deformed surface has to locally satisfy compatibility conditions (Gauss-Codazzi equations) on the first and second fundamental forms. We then give a method to locally modify the surface first and second fundamental forms in a compatible way. We use those fundamental forms to define surface plastic deformations, and finally recover output surface vertex positions by minimizing the surface elastic energy under the plastic deformations. We demonstrate that our method makes it possible to smoothly deform triangle meshes to large spatially varying strains and rotations, while meeting user constraints.
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Graphitic carbon nitride (g-C3N4) has received much attention due to its unique characteristics of stable physicochemical features, facile preparation, and inexpensive cost. However, the bulk g-C3N4 has a weak capacity for pollutant degradation and needs to be modified for real application. Therefore, extensive research has been done on g-C3N4, and the discovery of the novel zero-dimensional nanomaterials known as carbon quantum dots (CQDs) provided it with a unique modification option. In this review, the development for the removal of organic pollutants by g-C3N4/CQDs was discussed. Firstly, the preparation of g-C3N4/CQDs were introduced. Then, the application and the degradation mechanism of g-C3N4/CQDs were briefly described. And the discussion of the influencing factors on g-C3N4/CQDs' ability to degrade organic pollutants came in third. Finally, the conclusions of photocatalytic degradation of organic pollutants by g-C3N4/CQDs and future perspectives followed. This review will strengthen the understanding of the photocatalytic degradation of real organic wastewater by g-C3N4/CQDs, including their preparation, application, mechanism, and influencing factors.
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Subculture, includes animation, comics, games (ACG), and idol fan culture, is popular among young generations in Japan. Previous studies have shown different psychological outcomes within different subcultural groups; however, underlying mechanisms remain unclear. This study proposes that subcultural identity may play a crucial role in mental health outcomes by interweaving social support and reputation. We examined the interplay between subcultural identity, social support, reputation, and different psychological outcomes through structural equation modeling (N = 300). Furthermore, we trained neural networks (NN) by applying a deep learning algorithm to predict psychological outcomes of different subcultures. The results suggest identity related to anime, idol, and hip-hop was positively associated with anxiety, aggression, depressive symptoms, and suicidal tendencies. By contrast, fashion and sports identities associated with no adverse or positive psychological outcomes. Perceived reputation mediates adverse psychological outcomes in the ACG, idol, and hip-hop groups. The highest accuracy in our NN reached 71%, indicating that NN could be an effective tool for predicting mental problems. Our work points up an urgent need to improve the mental health of the young generation by de-stigmatizing discriminated cultural groups.
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To provide analytic materials for business management for smart retail solutions, it is essential to recognize various customer behaviors (CB) from video footage acquired by in-store cameras. Along with frequent changes in needs and environments, such as promotion plans, product categories, in-store layouts, etc., the targets of customer behavior recognition (CBR) also change frequently. Therefore, one of the requirements of the CBR method is the flexibility to adapt to changes in recognition targets. However, existing approaches, mostly based on machine learning, usually take a great deal of time to re-collect training data and train new models when faced with changing target CBs, reflecting their lack of flexibility. In this paper, we propose a CBR method to achieve flexibility by considering CB in combination with primitives. A primitive is a unit that describes an object's motion or multiple objects' relationships. The combination of different primitives can characterize a particular CB. Since primitives can be reused to define a wide range of different CBs, our proposed method is capable of flexibly adapting to target CB changes in retail stores. In experiments undertaken, we utilized both our collected laboratory dataset and the public MERL dataset. We changed the combination of primitives to cope with the changes in target CBs between different datasets. As a result, our proposed method achieved good flexibility with acceptable recognition accuracy.
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Comportamento do Consumidor , Projetos de Pesquisa , Coleta de DadosRESUMO
Intracranial aneurysms (IA) are abnormal expansions of the intracranial arteries. Once it ruptures, the mortality and disability rate are high. The cost of imaging examinations is high, and rupture risk cannot be predicted, making it difficult for high-risk groups to be screened and prevented. Thus, clinically effective biomarkers are required to screen high-risk groups, estimate the risk of rupture, and determine the appropriate early intervention step. This article introduces the current research and application of exosome-derived microRNA (miRNA) as biomarkers of intracranial aneurysms and their limitations, which can give researchers a general overview of the research in this field. It can also serve as a reference point for selecting related research directions.
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Farmland consolidation is an effective tool to improve farmland infrastructures, soil quality, and sustain a healthy farmland ecosystem and rural population, generating contributions to food security and regional sustainable development. Previous studies showed that farmland consolidation regulates soil physical and chemical properties. Soil microorganisms also play an important role in soil health and crop performance; however, few studies reported how farmland consolidation influence soil microecology. Here, we used DNA sequencing technology to compare bacterial community structure in farmlands with and without consolidation. DNA sequencing technology is the most advanced technology used to obtain biological information in the world, and it has been widely used in the research of soil micro-ecological environment. In September 2018, we collected soil samples in Jiashan County, Zhejiang Province, China, and used DNA sequence technology to compare the bacterial community structure in farmlands with and without consolidation. Our results found that (1) farmland consolidation had significant impacts on soil microbial characteristics, which were mainly manifested as changes in microbial biomass, microbial diversity and community structure. Farmland consolidation can increase the relative abundance of the three dominant bacteria phyla and the three fungal dominant phyla, but it also negatively affects the relative abundance of the six dominant bacteria phyla and the three fungal dominant phyla. (2) Farmland consolidation had an indirect impact on soil bacterial community structure by adjusting the soil physical and chemical properties. (3) The impact of heavy metals on bacterial community structure varied significantly under different levels of heavy metal pollution in farmland consolidation areas. There were 6, 3, 3, and 5 bacterial genera that had significant correlations with heavy metal content in cultivated land with low pollution, light pollution, medium pollution, and heavy pollution, respectively. The number of heavy metal-tolerant bacteria in the soil generally increased first and then decreased under heavy metal polluted conditions. Our study untangled the relationship between varied farmland consolidation strategies and bacteria through soil physcicochemical properties and metal pollution conditions. Our results can guide farmland consolidation strategies and sustain soil health and ecological balance in agriculture.
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Metais Pesados , Poluentes do Solo , Bactérias/genética , China , Ecossistema , Monitoramento Ambiental/métodos , Humanos , Metais Pesados/análise , Solo/química , Microbiologia do Solo , Poluentes do Solo/análiseRESUMO
Customer activity (CA) in retail environments, which ranges over various shopper situations in store spaces, provides valuable information for store management and marketing planning. Several systems have been proposed for customer activity recognition (CAR) from in-store camera videos, and most of them use machine learning based end-to-end (E2E) CAR models, due to their remarkable performance. Usually, such E2E models are trained for target conditions (i.e., particular CA types in specific store spaces). Accordingly, the existing systems are not malleable to fit the changes in target conditions because they require entire retraining of their specialized E2E models and concurrent use of additional E2E models for new target conditions. This paper proposes a novel CAR system based on a hierarchy that organizes CA types into different levels of abstraction from lowest to highest. The proposed system consists of multiple CAR models, each of which performs CAR tasks that belong to a certain level of the hierarchy on the lower level's output, and thus conducts CAR for videos through the models level by level. Since these models are separated, this system can deal efficiently with the changes in target conditions by modifying some models individually. Experimental results show the effectiveness of the proposed system in adapting to different target conditions.
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Comportamento do Consumidor , Meio AmbienteRESUMO
The development of a biodegradable cellulose-based separator with excellent performance has been of great research significance and application potential for the green development of supercapacitors. Herein, the regenerated porous cellulose/Polyvinyl alcohol films (CP-10, CP-15, CP-20, CP-25) with different mass ratio were successfully fabricated by a simple blending and phase inversion process. Their electrochemical properties as separators in assembled supercapacitor were evaluated. Fourier transform infrared spectroscopy and x-ray diffraction analysis indicate that intermolecular and intramolecular hydrogen bonding existed between cellulose and polyvinyl alcohol of the CP films. Compared with other CP films, the CP-20 film shows higher mechanical strength (28.02 MPa), better wettability (79.06°), higher porosity (59.69%) and electrolyte uptake (281.26 wt%). These properties of CP-20 are expected to show better electrochemical performance as separator. Indeed, the electrochemical tests, including electrochemical impedance spectroscopy, cyclic voltammetry, galvanostatic charge discharge, demonstrate that the SC-20 capacitor (with CP-20 as separator) shows the lowest equivalent series resistance of 0.57 Ω, the highest areal capacitance of 1.98 F cm-2 at 10 mV s-1, specific capacitance of 134.41 F g-1 and charge-discharge efficiency of 98.62% at 1 A g-1 among the four capacitors with CP films as separators. Comparing the assembled SC-40 and SC-30 with two commercial separators (TF4040 and MPF30AC) and SC-PVA with Polyvinyl alcohol (PVA) separator, the CV and GCD curves of SC-20 maintain the quasi rectangular and symmetrical triangular profiles respectively at different scan rates in potential window of 0-1 V. SC-20 exhibits the highest value of 28.24 Wh kg-1 at 0.5 A g-1 with a power density of 0.26 kW kg-1, and 13.41 Wh kg-1 at 10 A g-1 with a power density of 6.04 kW kg-1. SC-20 also shows the lowest voltage drop and the highest areal and specific capacitance. Moreover, SC-20 maintains the highest value of 86.81% after 4000 cycles compared to 21.18% of SC-40, 75.07% of SC-30, and 6.66% of SC-PVA, showing a superior rate capability of a supercapacitor. These results indicate that CP films can be served as promising separators for supercapacitors.
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The industrial advancement of high-performance technologies directly depends on the thermo-mechanical properties of materials. Here we give an account of a facile approach for the bulk production of a polyethylene terephthalate (PET)/polypropylene (PP)-based nanocomposite blend with Inorganic Fullerene Tungsten Sulfide (IF-WS2) nanofiller using a single extruder. Nanofiller IF-WS2 was produced by the rotary chemical vapor deposition (RCVD) method. Subsequently, IF-WS2 nanoparticles were dispersed in PET and PP in different loadings to access impact and their dispersion behavior in polymer matrices. As-prepared blend nanocomposites were characterized by scanning electron microscopy (SEM), transmission electron microscopy (TEM), thermogravimetric analysis (TGA), dynamic differential scanning (DSC), dynamic mechanical analysis (DMA), and X-ray diffraction (XRD). In this work, the tensile strength of the PP/PET matrix with 1% IF-WS2 increased by 31.8%, and the thermal stability of the sample PP/PET matrix with 2% increased by 18 °C. There was an extraordinary decrease in weight loss at elevated temperature for the nanocomposites in TGA analysis, which confirms the role of IF-WS2 on thermal stability versus plain nanocomposites. In addition, this method can also be used for the large-scale production of such materials used in high-temperature environments.