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A nylon-like polyester tire cord, which combined the characteristics of nylon and polyester tire cords, was designed as the carcass reinforcement material used to meet the increasing demands of the tire industry for performance and impact on the environment. Tires' carcass construction plays a crucial role in affecting handling performance and ride comfort. Small changes in the carcass component can lead to significant improvements in the total tire/vehicle performance. This study evaluated the performance of nylon-like polyester and nylon 6 motorcycle tires. The results showed that the nylon-like polyester tire passed all indoor tests, and post-cure inflation (PCI) could be eliminated, resulting in energy and cost savings. The rolling resistance coefficient of the nylon-like polyester tire was reduced by 6.8% compared to that of the nylon 6 control tire, which could save fuel and have a positive impact on the environment. Nylon-like polyester tire cord extracted from the experimental tire possessed a higher modulus compared to that of nylon 6 tire cord, which could lead to better handling and ride comfort performance. Morphological pictures showed that both nylon-like polyester and nylon 6 cords extracted from tires had a good rubber coverage and comparable adhesion properties.
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Aim: Patients with unstable angina pectoris (UAP) usually present anxiety or depression during percutaneous coronary intervention (PCI). This study sought to investigate the instant and short-term effects of acupuncture for anxiety and depression in UAP patients with PCI. Methods: A total of 210 UAP patients who underwent PCI were recruited and randomly assigned (1:1:1) to acupuncture, placebo, or control groups. Enzyme-linked immunosorbent assay was used to detect the levels of fasting glucose, fasting insulin, homeostasis model assessment of insulin resistance (HOMA-IR), interleukin-6 (IL-6), high-sensitivity C-reactive protein (Hs-CRP), advanced oxidation protein products (AoPPs), and oxidized low-density lipoprotein (OX-LDL). Serial questionnaires with the Hamilton Anxiety (HAMA) scale and the Pittsburgh Sleep Quality Index were evaluated, and heart rate variability indicators were obtained. Results: Primary end-point: low frequency/high frequency (HF) was lower in the electroacupuncture group (p = 0.014), while standard deviation of normal-to-normal intervals, average standard deviation of normal-to-normal intervals, percentage of successive intervals that differ more than 50â ms, and HF were increased with acupuncture (p = 0.018, p = 0.043, p = 0.016, and p = 0.002, respectively). Secondary end-point: significant improvements in anxiety levels (HAMA) were observed in the three groups (p < 0.001). The fasting insulin and HOMA-IR levels were similar between the control group and the acupuncture group (p = 0.285 and p = 0.165, respectively). The levels of IL-6 and AoPPs differed among the three groups (p = 0.021 and p < 0.001, respectively). However, no significant differences were found in fasting plasma glucose, fasting c-peptide, Hs-CRP, and OX-LDL levels among the three groups (p = 0.585, p = 0.611, p = 0.902, and p = 0.756, respectively). Conclusions: In this study, short-term acupuncture may potentially relieve clinical symptoms before PCI treatment. Clinical Trial Registration: ClinicalTrials.gov, identifier (NCT03789344).
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A tert-butyldiphenylsilyl-containing polyimide (PI-OSi) has been established as a colorimetric and ratiometric chemosensor for rapid detecting fluoride ions (F-). The UV-vis absorbance ratio value (A322/A288) of PI-OSi in a DMF solution displays a wide linear range change to F- concentrations with a detection limit (DL) value of 2.13 µM. Additionally, adding incremental amounts of F- to a DMF solution of PI-OSi shows an immediate color change to yellow and finally to green from colorless. More interestingly, the resulting PI-OSi plus F- system (PI-OSi·F) could detect trace water in DMF. The A292/A322 value of PI-OSi·F almost linearly increases with low water content, which suggests convenient quantitative sensing of trace water content in DMF. The DL value of PI-OSi·F for sensing water in DMF is determined to be 0.00149% (v/v). The solution color of PI-OSi·F returns to colorless when the water content increases, indicating that PI-OSi·F can conveniently estimate water content in DMF by naked-eye detection. The detection mechanisms confirmed by an 1H NMR study and a DFT calculation involve a F--induced desilylation reaction of PI-OSi to form phenolate anion followed by protonation with trace water. Finally, PI-OSi film was fabricated for the colorimetric detection of F- and water in CH3CN.
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Alpha-glucosidase (α-Glu) plays a crucial role in regulating the normal physiological function of the body; therefore, α-Glu activity detection is crucial in clinical studies. In this study, a nickel-based metal-organic framework (Ni-MOF) co-doped with sulfur dots (SDs) and iron (Fe) was designed and constructed for the colorimetric detection of α-Glu. The SDs/Fe/Ni-MOF shows a very low Michaelis-Menten constant (0.0466 mM) for H2O2, suggesting a very high affinity for H2O2. Additionally, the free radicals generated by the nanozyme-catalyzed reaction were analyzed, and the feasibility of the nanozyme-catalyzed process was further verified using density functional theory. The bimetallic (Fe and Ni) can improve the catalytic activity of the material, and sulfur can improve the affinity with the substrate to further enhance the catalytic performance. Notably, hydroquinone (HQ) inhibits nanozyme activity, whereas α-Glu hydrolyzes alpha-arbutin (α-Arb) and subsequently produces HQ. Therefore, this study developed a method for detecting α-Glu activity using α-Arb as a substrate. This method has high selectivity, a wide detection range (1.00-100 U L-1), and a low detection limit (0.525 U L-1). Finally, the method was used to α-Glu activity detected in serum samples with good accuracy. This study provides a new method for the detection of α-Glu.
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Peróxido de Hidrogênio , Estruturas Metalorgânicas , alfa-Glucosidases , Antagonistas de Receptores de Angiotensina , Inibidores da Enzima Conversora de Angiotensina , Colorimetria/métodos , Ferro , Níquel , Enxofre/química , Nanopartículas/químicaRESUMO
Species distribution models (SDMs) are effective tools for wildlife conservation and management, as they employ the quantification of habitat suitability and environmental niches to evaluate the patterns of species distribution. The utilization of SDMs at various scales in a hierarchical approach can provide additional and complementary information, significantly improving decision-making in local wildlife conservation initiatives. In this study, we considered the appropriate spatial scale and data resolution to execute species distribution modeling, as these factors greatly influence the modeling procedures. We developed SDMs for wintering black storks at both the regional and local scales. At the regional scale, we used climatic and climate-driven land use/land cover (LULC) variables, along with wintering occurrence points, to develop models for mainland China. At the local scale, we used local environmental variables and locally gathered wintering site data to develop models for Shaanxi province. The predictions from both the regional and local models were then combined at the provincial level by overlapping suitable areas based on climatic and local conditions. We compared and evaluated the resulting predictions using seven statistical metrics. The national models provide information on the appropriate climatic conditions for the black stork during the wintering period throughout China, while the provincial SDMs capture the important local ecological factors that influence the suitability of habitats at a finer scale. As anticipated, the national SDMs predict a larger extent of suitable areas compared to the provincial SDMs. The hierarchical prediction approach is considered trustworthy and, on average, yields better outcomes than non-hierarchical methods. Our findings indicate that human-driven LULC changes have a significant and immediate impact on the wintering habitat of the black stork. However, the effects of climate change seem to be reducing the severity of this impact. The majority of suitable wintering habitats lie outside the boundaries of protected areas, highlighting the need for future conservation and management efforts to prioritize addressing these conservation gaps and focusing on the protection of climate refuges.
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The detection of pharmaceuticals has been a matter of concern among scientists and health researchers in the past few decades. However, it is still difficult to realize the sensitivity and selectivity detection of pharmaceuticals with similar structures. Herein, the pharmaceutical molecules of 2-mercaptobenzimidazole (MBI) and 2-mercaptobenzothiazole (MBT) with so similar structures can be selectively detected by surface-enhanced Raman spectroscopy (SERS) taking advantage of the fingerprint identification on Au/MIL-101(Cr), with sensitive detection limits of 0.5 ng·mL-1 for MBI and 1 ng·mL-1 for MBT. MBI is selectively enriched by Au/MIL-101(Cr) from the mixture solution and detected by SERS below 30 ng·mL-1. MBI can also be selectively detected in the serum samples with a detection limit of 10 ng·mL-1. Density functional theory calculations combined with the SERS experiments explained that the high sensitivity and selectivity are caused by the intrinsic differences in Raman intensity and different adsorption energies from the pharmaceutical molecules adsorbed on Au/MIL-101(Cr), respectively. This study provides an effective way to enrich and detect pharmaceutical molecules with similar structures.
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Nanopartículas Metálicas , Estruturas Metalorgânicas , Ouro/química , Análise Espectral Raman/métodos , Preparações Farmacêuticas , Nanopartículas Metálicas/químicaRESUMO
Background: Percutaneous coronary intervention (PCI) is currently the main treatment of acute ST-segment elevated myocardial infarction (STEMI), whereafter various postoperative adverse events often occur. Central arterial pressure (CAP) is closely related to the pathophysiological process of cardiovascular disease, and its relationship with outcomes after PCI in STEMI patients remains unclear. The aim of this study was to observe the relationship between pre-PCI CAP and in-hospital outcomes in STEMI patients which might be helpful to evaluate prognosis. Methods: A total of 512 STEMI patients who underwent emergency PCI were included. Baseline data and CAP information before PCI and in-hospital outcomes were collected. Multivariate logistic regression was used to adjust for confounding factors. Potential non-linear relationships between CAP and in-hospital outcomes were described using a restricted cubic bar plot. The area under the receiver operating characteristic (ROC) curve (AUC), net reclassification index, and composite discriminant improvement index were used to analyze the correlation between CAP and outcomes during hospitalization. Results: Among the 512 patients, 116 experienced at least 1 in-hospital major adverse cardiovascular events (MACEs), with an incidence rate of 22.60%. Among CAP indicators, higher [>137.5 mmHg, OR =2.70, 95% confidence interval (CI): 1.20-6.06] or lower (<102 mmHg, OR =7.55, 95% CI: 3.45-16.52) central systolic pressure (CSP), lower (<61 mmHg, OR =2.78, 95% CI: 1.36-5.67) central diastolic pressure (CDP), higher (>55 mmHg, OR =2.09, 95% CI: 1.01-4.31) or lower (<29 mmHg, OR =3.28, 95% CI: 1.54-7.00) central pulse pressure (CPP), and higher (>101 mmHg, OR =2.07, 95% CI: 1.01-4.61) or lower (<76 mmHg, OR =4.91, 95% CI: 2.31-10.44) central mean pressure (CMP) were independent risk factors for MACEs. The relationship between CSP and CMP and in-hospital outcomes showed a "J"-shaped relationship, CDP and in-hospital outcomes showed an "L"-shaped relationship, and CPP and in-hospital outcomes showed a "U"-shaped relationship. There was no statistical difference in the prediction ability of in-hospital outcomes detected between CSP, CDP, and CMP (P>0.05), but the comparison of the 3 with CPP was statistically significant (P<0.05). Conclusions: CSP, CDP, and CMP have certain predictive ability for postoperative in-hospital outcomes in STEMI patients and can be used during percutaneous intervention.
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In existing separation membranes, it is difficult to quickly produce large-area graphene oxide (GO) nanofiltration membranes with high permeability and high rejection, which is the bottleneck of industrialization. In this study, a pre-crosslinking rod-coating technique is reported. A GO-P-Phenylenediamine (PPD) suspension was obtained by chemically crosslinking GO and PPD for 180 min. After scraping and coating with a Mayer rod, the ultra-thin GO-PPD nanofiltration membrane with an area of 400 cm2 and a thickness of 40 nm was prepared in 30 s. The PPD formed an amide bond with GO to improve its stability. It also increased the layer spacing of GO membrane, which could improve the permeability. The prepared GO nanofiltration membrane had a 99 % rejection rate for dyes such as methylene blue, crystal violet, and Congo red. Meanwhile, the permeation flux reached to 42 LMH/bar, which was 10 times that of the GO membrane without PPD crosslinking, and it still maintained excellent stability under strongly acidic and basic conditions. This work successfully solved the problems of GO nanofiltration membranes, including the large-area fabrication, high permeability and high rejection.
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For cereal crops, such as rice, the grain yield mainly comes from the accumulation of carbohydrates in the seed, which depends ultimately on photosynthesis during the growth period. To create early ripen variety, higher efficiency of photosynthesis is thus necessary to get higher grain yield with shorter growth period. In this study, flowering early was observed in the hybrid rice with overexpression of OsNF-YB4. Along with the flowering early, the hybrid rice also was shorter in plant height with less of leaves and internodes, but no changes of panicle length and leaf emergence. The grain yield was kept or even increased in the hybrid rice with shorter growth period. Transcription analysis revealed that Ghd7-Ehd1-Hd3a/RFT1 was activated early to promote the flowering transition in the overexpression hybrids. RNA-Seq study further showed that carbohydrate-related pathways were significantly altered in addition to circadian pathway. Notably, up-regulation of three pathways related to plant photosynthesis was observed, as well. Increased carbon assimilation with alteration of chlorophyll contents was subsequently detected in the following physiological experiments. All these results demonstrate that overexpression of OsNF-YB4 in the hybrid rice activates flowering early and improves photosynthesis resulting in better grain yield with shorter growth period.
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Oryza , Oryza/metabolismo , Grão Comestível/genética , Fotossíntese/genética , Folhas de Planta/metabolismo , Clorofila/metabolismo , Regulação da Expressão Gênica de PlantasRESUMO
Objectives: Live-streaming fitness is perceived by the Chinese government as an invaluable means to reduce the prevalence of physical inactivity amid the COVID-19 pandemic. This study aims to investigate the public altitudes of the Chinese people toward live-streaming fitness and provide future health communication strategies on the public promotion of live-streaming fitness accordingly. Methods: This study collected live-streaming fitness-related microblog posts from July 2021 to June 2022 in Weibo, the Chinese equivalent to Twitter. We used the BiLSTM-CNN model to carry out the sentiment analysis, and the structured topic modeling (STM) method to conduct content analysis. Results: This study extracted 114,397 live-streaming fitness-related Weibo posts. Over 80% of the Weibo posts were positive during the period of the study, and over 85% were positive in half of the period. This study finds 8 topics through content analysis, which are fitness during quarantine; cost reduction; online community; celebrity effect; Industry; fitness injuries; live commerce and Zero Covid strategy. Conclusions: It is discovered that the public attitudes toward live-streaming fitness were largely positive. Topics related to celebrity effect (5-11%), fitness injuries (8-16%), live commerce (5-9%) and Zero Covid strategy (16-26%) showed upward trends in negative views of the Chinese people. Specific health communication strategy suggestions are given to target each of the negative topics.
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COVID-19 , Mídias Sociais , Humanos , Pandemias , COVID-19/epidemiologia , China , AtitudeRESUMO
The COVID-19 pandemic has created an urgent need for volunteers to complement overwhelmed public health systems. This study aims to explore Chinese people's attitudes toward volunteerism amid the COVID-19 pandemic. To this end, we identify the latent topics in volunteerism-related microblogs on Weibo, the Chinese equivalent of Twitter using the topic modeling analysis via Latent Dirichlet Allocation (LDA). To further investigate the public sentiment toward the topics generated by LDA, we also conducted sentiment analysis on the sample posts using the open-source natural language processing (NLP) technique from Baidu. Through an in-depth analysis of 91,933 Weibo posts, this study captures 10 topics that are, in turn, distributed into five factors associated with volunteerism in China as motive fulfillment (n = 31,661, 34.44%), fear of COVID-19 (n = 22,597, 24.58%), individual characteristic (n = 17,688, 19.24%), government support (n = 15,482, 16.84%), and community effect (n = 4,505, 4.90%). The results show that motive fulfillment, government support, and community effect are the factors that could enhance positive attitudes toward volunteerism since the topics related to these factors report high proportions of positive emotion. Fear of COVID-19 and individual characteristic are the factors inducing negative sentiment toward volunteerism as the topics related to these factors show relatively high proportions of negative emotion. The provision of tailored strategies based on the factors could potentially enhance Chinese people's willingness to participate in volunteer activities during the COVID-19 pandemic.
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Organic perovskites are promising optoelectronic semiconductor materials with photoelectric applications. It is known that the luminescence of perovskites is highly sensitive to hydron molecules due to its low moisture resistance of crystal structure, indicating its potential application on humidity-sensing. Herein, a novel perovskite-based compound (PBC) with minimal defects was developed to promote the photoluminescence performance via optimization of the drying method and precursor constitutions. Perovskite materials with good structural integrity and enhanced fluorescence performance up to four times were obtained from supercritical drying. Moreover, the hydrophilic polymer matrix, polyethylene oxide (PEO), was added to obtain a composite of perovskite/PEO (PPC), introducing enhanced humidity sensitivity and solution processibility. These perovskite/PEO composites also exhibited long-term stability and manifold cycles of sensitivity to humidity owing to perovskite encapsulation by PEO. In addition, this precursor solution of perovskite-based composites could be fancily processed by multiple methods, including printing and handwriting, which demonstrates the potential and broaden the applications in architecture decoration, logos, trademarks, and double encryption of anti-fake combined with humidity.
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Mental health attitude has huge impacts on the improvement of mental health. In response to the ongoing damage the COVID-19 pandemic caused to the mental health of the Chinese people, this study aims to explore the factors associated with mental health attitude in China. To this end, we extract the key topics in mental health-related microblogs on Weibo, the Chinese equivalent of Twitter, using the structural topic modeling (STM) approach. An interaction term of sentiment polarity and time is put into the STM model to track the evolution of public sentiment towards the key topics over time. Through an in-depth analysis of 146,625 Weibo posts, this study captures 12 topics that are, in turn, classified into four factors as stigma (n = 54,559, 37.21%), mental health literacy (n = 32,199, 21.96%), public promotion (n = 30,747, 20.97%), and social support (n = 29,120, 19.86%). The results show that stigma is the primary factor inducing negative mental health attitudes in China as none of the topics related to this factor are considered positive. Mental health literacy, public promotion, and social support are the factors that could enhance positive attitudes towards mental health, since most of the topics related to these factors are identified as positive ones. The provision of tailored strategies for each of these factors could potentially improve the mental health attitudes of the Chinese people.
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COVID-19 , Mídias Sociais , Atitude , Atitude Frente a Saúde , COVID-19/epidemiologia , China/epidemiologia , Humanos , Saúde Mental , PandemiasRESUMO
From the perspective of emotional preference, studies have been conducted about landscape healing for subhealth people in the National High-Tech Zone (the study area). Combined with a preliminary practice investigation, Unity 2019 was used to make a digital roaming landscape, and 91 subjects with a history of mental subhealth diseases were randomly invited to participate in the immersive experimentation of the Human-Machine Environment Synchronisation (ErgoLAB) platform. After the experiment, the subjects were invited to fill in a Likert scale as the control group. The interest preference, emotion fluctuation, and healing effect of landscape colour were verified. The results show that: (1) The variation trend of interest reflected the concentration of interest in landscape, and the order of degree of interest, ranging from high to low, went Green > Yellow > Blue > Red > Orange > Purple > Cyan. (2) The subjects' interest in landscape colour was correlated with the arousal of positive emotions. The correlation between interest in landscape colour and positive emotions, from high to low, went Blue > Green > Yellow, while the correlation between red, cyan, orange, and purple was not significant. (3) The mean skin conductance (SC) fluctuation variance of subjects was 5.594%, which confirmed that the healing effect of digital roaming landscape scenes was significant under the state of low arousal. According to the Likert scale data, subjects' scores of the healing effect of landscapes, from high to low, went as follows: Green > Yellow > Red > Blue > Cyan > Orange > Purple. The results provide a new method for demonstrating the logical relationship between the digital landscape interest experience-emotional awakening-healing effect and providing a theoretical method and construction scheme for landscape colour configuration in the implementation of landscape healing projects.
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Percepção de Cores , Emoções , Nível de Alerta , Cor , HumanosRESUMO
Impacted by the COVID-19 epidemic, the human sub-health in national high-tech zones (hereinafter referred to as high-tech zones) has become more prominent. It is critical for the mental sub-health group in the high-tech zone to relieve the anxiety and tension caused by the pressure of life and work. This paper uses SketchUp virtual engine (Unity 2019) software, and 3D roaming technology to carry out the ecological landscape transformation design of the Baotzixi ecological corridor in the East Lake High-tech Zone, to construct a 3D roaming landscape scene and measure its therapeutic effect by inviting subjects to participate in an interactive experience experiment on the ErgoLAB platform. The results illustrate that: (1) the thermogram trend shows that the more attractive the 3D roaming landscape scene is, the stronger the subjects' interest is; (2) the participants have a positive emotional arousal state in the immersive experience of the 3D roaming landscape scene after the modification design; and (3) the mean skin conductance (SC) fluctuation variance of the subjects is 5.819%, indicating that the healing effect is significant in the state of positive emotional arousal. The research results show that there is a connection between the subjects and the 3D roaming landscape scene after the transformation design of "high interest, emotional arousal and significant healing".
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COVID-19 , COVID-19/epidemiologia , Humanos , Lagos , Software , TecnologiaRESUMO
Faradaic efficiency for the nitrogen reduction reaction (NRR) is often limited by low N2 solubility in the electrolyte, while a large number of intimate contacts between the electrolyte and solid catalyst can also inevitably sacrifice many active sites for the NRR. Here, it is reported that a "quasi-gas-solid" interface formed in donor-acceptor-based conjugated polymers (CPs) is beneficial to boosting the NRR process and at the same time suppressing the competing hydrogen evolution reaction. Of particular interest, it is found that a semicrystalline CP catalyst, SC-PBDT-TT, exhibits a high Faradaic efficiency of up to 60.5% with a maximum NH3 production rate of 16.8 µg h-1 mg-1 in a neutral-buffered seawater electrolyte. Molecular dynamics and COMSOL Multiphysics simulations reveal the origin of the observed high NRR performance arising from the presence of desirable crystal regions to resist the penetration of H2 O molecules, leading to the formation of a "quasi-gas-solid" interface inside the catalyst for a favorable direct-contact between the catalyst and N2 molecules. Furthermore, high-throughput computations, based on density functional theory, reveal the actual real active site for N2 adsorption and reduction in SC-PBDT-TT. This work provides a new framework for optimizing NRR performance of metal-free catalysts by controlling their crystallinities.
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PURPOSE: The vulnerable children refer to the special group of children with deviation in the process of children's psychological development and personality formation due to growth dilemmas. MATERIALS AND METHODS: This may incur a series of serious social and family problems. The vulnerable children mainly cover the children suffering from children's psychological problems, such as childhood autism, autism, social anxiety and hypersensitivity, fear, depression, and PTSD arising from other factors. At present, the research results at home and abroad mainly focus on the psychological dynamic correlation investigation and solution discussion of a certain kind of difficult factor in the children's psychological development based on statistical data by the experimental methods, such as scale and model, and there is a blind spot in the humanistic orientation theory construction of psychological treatment for vulnerable children, causing the social reflection on children's psychological predicament from the humanistic perspective cannot be performed in related researches and going against searching for universal and integral theoretical paradigm for solving related problems. RESULTS: Sophisticated technologies for the observations have emerged increasingly for enabling the psychological features of vulnerable children through developmental cognitive neuroscience experiments. CONCLUSION: This paper introduces humanistic art therapy theory, focuses on the construction of a theoretical paradigm, and verifies its effectiveness based on the experimental results on the psychological development of vulnerable children, with an efficient performance.IMPLICATIONS FOR REHABILITATIONThis study mainly refers to children with difficulty in social inclusion and psychological development.The results showed that two kinds of art therapy can obviously improve the psychological disorders of vulnerable children.The goal was to enhance self-cognition, strengthen emotional interaction, and implement positive motivation.
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A new dual-mode ratiometric fluorescence and colorimetric probe for selective determination of Cu2+ was developed based on blue-emission sulfur quantum dots (SQDs) and yellow-emission carbon quantum dots (CQDs). The fluorescence and absorbance of CQDs increased in the presence of Cu2+ due to the Cu2+ -oxidized o-phenylenediamine group on the surface of the CQDs. Because of the inner filter effect between SQDs and CQDs-Cu2+, the fluorescence response of SQDs decreased following the introduction of Cu2+. Furthermore, in the presence of Cu2+, the dual-mode SQD-CQD probe showed visible color changes under both ultraviolet light and sunlight. Under optimal conditions, the dual-mode probe was used to quantitatively detect Cu2+ with a linear range of 0.1-5.0 µM for ratiometric fluorescence and colorimetry, with a limit of detection of about 31 nM and 47 nM, respectively. Finally, the dual-mode probe was used for the determination of Cu2+ in practical samples to expand the practical application, and the difference between ratiometric fluorescence and colorimetric methods was compared. The recovery results confirmed the high accuracy of the dual-mode probe, showing that it has immense potential for sensitive and selective detection of Cu2+ in practical samples.
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Waterproof and breathable membranes (WBMs) have drawn broad attention due to their widespread applications in various scientific and industry fields. However, creating WBMs with environment-friendliness and high performance is still a critical and challenging task. Herein, an environmentally friendly fluorine-free WBM with high performance was prepared through electrospinning and one-step dip-coating technology. The fluorine-free waterborne hydroxyl acrylic resin (HAR) emulsion containing long hydrocarbon chains endowed the electrospun polyacrylonitrile/blocked isocyanate prepolymer (PAN/BIP) fibrous membranes with superior hydrophobicity; meanwhile, crosslinking agent BIP ensured strong chemical binding between hydrocarbon segments and fiber substrate. The as-prepared PAN/BIP@HAR fibrous membranes achieve ideal properties with waterproofness of 112.5 kPa and moisture permeability of 12.7 kg m-2 d-1, which are comparable to the existing high-performance fluorinated WBMs. Besides, the PAN/BIP@HAR membranes also display impressive tensile strength and durability. Significantly, the proposed technology was also applicable to other hydrophilic fiber substrates, such as cellulose acetate and polyamide 6. The successful synthesis of environmentally friendly, durably waterproof, and highly breathable PAN/BIP@HAR membranes not only opens a new avenue to materials design, but also provides promising candidates with tremendous potential in various areas.
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Flowering time or heading date is a critical agronomic trait of rice and is regulated by numerous genes, including several genes encoding nuclear factor YB (NF-YB) in rice, NF-YB11 is one of the genes well known to be involved in the process, delaying flowering under long-day (LD) conditions but promoting flowering under short-day (SD) conditions. In this study, we identified another NF-YB gene, OsNF-YB4. Overexpression of OsNF-YB4 promoted rice flowering under both natural long-day (NLD) and natural short-day (NSD) conditions, whereas suppression or loss-of-function of this gene delayed flowering. The transcription of OsNF-YB4 exhibited an obvious circadian pattern and was induced by light under both LD and SD conditions. Expression analyses of flowering regulators in the photoperiodic flowering pathway demonstrated that up-regulation of OsNF-YB4 resulted in down-regulation of floral repressor Grain number, plant height and heading date 7 (Ghd7), and thus activating the Early heading date 1 (Ehd1)-mediated flowering pathway. Besides, OsNF-YB4 was observed to bind to the specific CCAAT-box regions in the Ghd7 promoter in vitro and interact with GHD7 in yeast. All these evidences support that OsNF-YB4 functions as a flowering promoter by negatively regulating the expression of floral repressor Ghd7 in rice photoperiodic flowering-time regulatory network.