RESUMO
In the push to achieve net-zero emissions by 2050, nuclear power will play an essential role alongside renewable wind and solar power, and correspondingly global interest and investment in this well-established technology is accelerating. The uranium present in seawater could support nuclear power generation for centuries, but traditional adsorptive separation strategies have proven ineffective for the selective extraction of uranium from this vast resource. Here, we report the synthesis of nanowires of a triazine-linked two-dimensional covalent organic framework via a solvent modulation approach, which can be used to access nanowire external diameters ranging from 50 to 200 nm. The 100 nm nanowires are exceptionally promising for the capture of uranium(VI) via photocatalytic reduction. Under simulated sunlight and without the use of sacrificial agents, the nanowires achieve a uranium uptake of 10.9 g/g from a 100 ppm uranyl(VI) solution, which is the highest reported to date among materials studied for photo and electrocatalytic uranium capture. Significantly, these nanowires exhibit a uranium adsorption capacity of 34.5 mg/g after exposure to seawater under irradiation for 42 days, a record among all materials reported to date for uranium capture.
RESUMO
Hydrogen sulfide (H2S) plays a critical role in cancer biology. Herein, we developed a series of glycosidase-triggered hydrogen sulfide (H2S) donors by connecting sugar moieties (including glucose, galactose and mannose) to COS donors via a self-immolative spacer. In the presence of corresponding glycosidases, H2S was gradually released from these donors in PBS buffer with releasing efficiencies from 36 to 67 %. H2S release was also detected by H2S probe WSP-1 after treatment HepG2 cells with Man1. Cytotoxicities of these glycosylated H2S donors were evaluated against HepG2 by MTT assay. Among them, Man1 and Man2 exhibited an obvious reduction of cell viability in HepG2 cells, with cell viability as 37.6 % for 80 µM of Man. Consistently, significant apoptosis was observed in HepG2 cells after treatment with Man1 and Man2. Finally, We evaluated the potential of Man1 for combination therapy with doxorubicin. A synergistic effect was observed between Man1 and Doxorubicin in HepG2 and Hela cells. All these results indicated glycosidase-activated H2S donorshave promising potential for cancer therapy.
Assuntos
Sulfeto de Hidrogênio , Humanos , Células HeLa , Sulfeto de Hidrogênio/farmacologia , Óxidos de Enxofre , Doxorrubicina/farmacologia , Glicosídeo HidrolasesRESUMO
Gut microbiota plays a crucial role in modulating pig development and health, and gut microbiota characteristics are associated with differences in feed efficiency. To answer open questions in feed efficiency analysis, biologists seek to retrieve information across multiple heterogeneous data sources. However, this is error-prone and time-consuming work since the queries can involve a sequence of multiple sub-queries over several databases. We present an implementation of an ontology-based Swine Gut Microbiota Federated Query Platform (SGMFQP) that provides a convenient, automated, and efficient query service about swine feeding and gut microbiota. The system is constructed based on a domain-specific Swine Gut Microbiota Ontology (SGMO), which facilitates the construction of queries independent of the actual organization of the data in the individual sources. This process is supported by a template-based query interface. A Datalog+-based federated query engine transforms the queries into sub-queries tailored for each individual data source, and an automated workflow orchestration mechanism executes the queries in each source database and consolidates the results. The efficiency of the system is demonstrated on several swine feeding scenarios.
Assuntos
Microbioma Gastrointestinal , Interface Usuário-Computador , Animais , Suínos , Bases de Dados Factuais , Fonte de Informação , SemânticaRESUMO
A highly efficient chlorobenzene-degrading strain was isolated from the sludge of a sewage treatment plant associated with a pharmaceutical company. The strain exhibited a similarity of over 99.9% with multiple strains of Paenarthrobacter ureafaciens. Therefore, the strain was suggested to be P. ureafaciens LY. This novel strain exhibited a broad spectrum of pollutant degradation capabilities, effectively degrading chlorobenzene and other organic pollutants, such as 1, 2, 4-trichlorobenzene, phenol, and xylene. Moreover, P. ureafaciens LY co-metabolized mixtures of chlorobenzene with 1, 2, 4-trichlorobenzene or phenol. Evaluation of its degradation efficiency showed that it achieved an impressive degradation rate of 94.78% for chlorobenzene within 8 h. The Haldane-Andrews model was used to describe the growth of P. ureafaciens LY under specific pollutants and its concentrations, revealing a maximum specific growth rate (µmax ) of 0.33 h-1 . The isolation and characterization of P. ureafaciens LY, along with its ability to degrade chlorobenzene, provides valuable insights for the development of efficient and eco-friendly approaches to mitigate chlorobenzene contamination. Additionally, investigation of the degradation performance of the strain in the presence of other pollutants offers important information for understanding the complexities of co-metabolism in mixed-pollutant environments.
Assuntos
Clorobenzenos , Poluentes Ambientais , Micrococcaceae , Biodegradação Ambiental , Clorobenzenos/metabolismo , Fenol , Preparações FarmacêuticasRESUMO
Nanofibers were prepared by electrospinning a mixture of polycaprolactone and silica, and modified to improve the hydrophilicity and stability of the material and to degrade nitrogenous wastewater by adsorbing heterotrophic nitrifying aerobic denitrifying (Ochrobactrum anthropic). The immobilized bacteria showed highly efficient simultaneous nitrification-denitrification ability, which could convert nearly 90 % of the initial nitrogen into gaseous nitrogen under aerobic conditions, and the average TN removal rate reached 5.59 mg/L/h. The average ammonia oxidation rate of bacteria immobilized by modified nanofibers was 7.36 mg/L/h, compared with 6.3 mg/L/h for free bacteria and only 4.23 mg/L/h for unmodified nanofiber-immobilized bacteria. Kinetic studies showed that modified nanofiber-immobilized bacteria complied with first-order degradation kinetics, and the effects of extreme pH, temperature, and salinity on immobilized bacteria were significantly reduced, while the degradation rate of free bacteria produced larger fluctuations. In addition, the immobilized bacterial nanofibers were reused five times, and the degradation rate remained stable at more than 80 %. At the same time, the degradation rate can still reach 50 % after 6 months of storage at 4 °C. It also demonstrated good nitrogen removal in practical wastewater treatment.
Assuntos
Nanofibras , Águas Residuárias , Desnitrificação , Nitritos/metabolismo , Nitrogênio/metabolismo , Cinética , Aerobiose , Nitrificação , Bactérias/metabolismo , Processos HeterotróficosRESUMO
The present work has aimed at gaining a deeper understanding of the effects of shear flow on the behaviors of nano filler evolution inside linear and long chain branched polymer matrices. Accordingly, measurements consisting of transient start-up shear rheology coupled with small amplitude oscillatory sweep (SAOS) and dielectric tests were designed. Linear polypropylene (PPC) and polypropylene (PPH) with long chain branching (LCB) were chosen as the polymer matrices and carbon nanotubes (CNTs) as the nanofillers. The percolation threshold of the LCB PPH nanocomposites was found to be higher than for linear PPC, due to the high viscosity and elasticity of LCB PPH. A transient shear with different shear rates was imposed on the composites after which SAOS and electrical conductivity measurements were conducted. The liquid-solid transitions of the nanocomposites were found to be different and to depend on the shear flow conditions (shear rate). For the linear PPC, higher shear rates caused the filler network to break down while lower shear rates helped the nanofillers to agglomerate. Interestingly, for LCB PPH, both higher and lower pre-shear rates resulted in the breakup of the filler networks, which was due to the restricted mobility of the CNTs by the LCB. The confinement of the polymer chains to the CNTs and their aggregates made it difficult for the fillers to move thus causing the formed network to be easily destroyed even under slow and slight shears. Similarly, the trend was also found after shear flows as reflected by the increase and decrease of electrical conductivities.
RESUMO
To inhibit the COVID-19 (Coronavirus disease 2019) outbreak, unprecedented nationwide lockdowns were implemented in China in early 2020, resulting in a marked reduction of anthropogenic emissions. However, reasons for the insignificant improvement in air quality in megacities of northeast China, including Shenyang, Changchun, Jilin, Harbin, and Daqing, were scarcely reported. We assessed the influences of meteorological conditions and changes in emissions on air quality in the five megacities during the COVID-19 lockdown (February 2020) using the WRF-CMAQ model. Modeling results indicated that meteorology contributed a 14.7% increment in Air Quality Index (AQI) averaged over the five megacities, thus, the local unfavorable meteorology was one of the causes to yield little improved air quality. In terms of emission changes, the increase in residential emissions (+15%) accompanied by declining industry emissions (-15%) and transportation (-90%) emissions resulted in a slight AQI decrease of 3.1%, demonstrating the decrease in emissions associated with the lockdown were largely offset by the increment in residential emissions. Also, residential emissions contributed 42.3% to PM2.5 concentration on average based on the Integrated Source Apportionment tool. These results demonstrated the key role residential emissions played in determining air quality. The findings of this study provide a scenario that helps make appropriate emission mitigation measures for improving air quality in this part of China.
Assuntos
Poluentes Atmosféricos , Poluição do Ar , COVID-19 , Humanos , COVID-19/epidemiologia , Poluentes Atmosféricos/análise , Cidades , Material Particulado/análise , Monitoramento Ambiental , Controle de Doenças Transmissíveis , Poluição do Ar/análise , China/epidemiologiaRESUMO
Biochar is considered a good activator for use in advanced oxidation technology. However, dissolved solids (DS) released from biochar cause unstable activation efficiency. Biochar prepared from saccharification residue of barley straw (BC-SR) had less DS than that prepared directly from barley straw (BC-O). Moreover, BC-SR had a higher C content, degree of aromatization, and electrical conductivity than BC-O. Although the effects of BC-O and BC-SR on activation of Persulfate (PS) to remove phenol were similar, the activation effect of DS from BC-O was 73% higher than that of DS from BC-SR. Moreover, the activation effect of DS was shown to originate from its functional groups. Importantly, BC-SR had higher activation stability than BC-O owing to the stable graphitized carbon structure of BC-SR. Identification of reactive oxygen species showed that SO4â¢-, â¢OH, and 1O2 were all effective in degradation by BC-SR/PS and BC-O/PS systems, but their relative contributions differed. Furthermore, BC-SR as an activator showed high anti-interference ability in the complex groundwater matrix, indicating it has practical application value. Overall, this study provides novel insight that can facilitate the design and optimization of a green, economical, stable, and efficient biochar-activated PS for groundwater organic pollution remediation.
Assuntos
Fenol , Poluentes Químicos da Água , Poluentes Químicos da Água/química , Sulfatos/química , Fenóis/análise , Carvão Vegetal/química , OxirreduçãoRESUMO
Porcine epidemic diarrhea virus (PEDV) frequently causes diarrhea outbreaks. However, whether newly discovered enteric viruses such as porcine kobuvirus (PKV) and porcine astroviruses (PAstVs) are also correlated with diarrhea is still unclear. Diarrhea outbreaks were reported in a PEDV-vaccinated pig farm in Xinjiang Uygur Autonomous Region of China from 2019 to 2020. PEDV was a common pathogen detected in fecal samples by routine RT-PCR assays. The PEDV positive fecal sample was used for pathogenic analysis due to the failure isolation of PEDV. The challenged neonatal piglets appeared watery diarrhea within one day post infection (dpi) and all died within 6 dpi. Histopathological and immunohistochemical examinations supported that PEDV is a major pathogen causing intestinal lesions. To further explore enteric viruses associated with neonatal piglet diarrhea, metagenomics sequencing was performed for the diarrheic piglets. Remarkably, PKV was the most abundant virus (58.33%) followed by PEDV (34.45%) and PAstVs (7.22%), which were also confirmed by real-time RT-PCR assays. Significant in vivo replications of PEDV and PKV could only be observed in challenged piglets whilst PAstVs maintained similar virus loads in both challenged and mock infected piglets. Overall, this study provides first pathogenic and metagenomic evidence that significant proliferations of PEDV and PKV are closely associated with severe diarrhea in neonatal piglets, while PAstVs likely play limited roles in neonatal piglet diarrhea.
Assuntos
Infecções por Coronavirus , Kobuvirus , Vírus da Diarreia Epidêmica Suína , Doenças dos Suínos , Animais , Diarreia/epidemiologia , Kobuvirus/genética , Mamastrovirus , Metagenômica , Vírus da Diarreia Epidêmica Suína/genética , SuínosRESUMO
Since seniors are more susceptible to ambient fine particulate matter (PM2.5), the high economic cost to protect the aged population from PM2.5 exposure is expected. Significant efforts have been made in China to mitigate PM2.5 since 2013 under the Air Pollution Prevention and Control Action (APPCA) Plan, which remarkably reduced PM2.5 contamination and its associated economic and health burdens. However, to what extent population aging could influence the economic benefits from the APPCA Plan is unclear. Here, we estimate five driving factors contributing to the economic cost of mortality attributable to PM2.5 pollution. The results show that the economic cost attributed to PM2.5 pollution increased from 1980 to 2013 and decreased from 2013 to 2019 in China, benefiting from the APPCA Plan. Since 2013, population aging becomes the most significant positive driver that almost offsets declining economic cost from significantly declining PM2.5. Rapid aging has become an enormous burden to PM2.5-associated health and economic loss. Our findings suggest that we should further improve air quality and enhance health care for the elderly population.
RESUMO
Industry relocation under globalization has altered the origins and strength of emission sources of many air pollutants. We develop global emission inventories of polycyclic aromatic hydrocarbons (PAHs) embodied in the production and consumption of goods and services. We implement these inventories within a global atmospheric transport model and simulate spatial-temporal changes in atmospheric concentrations of benzo[α]pyrene (BaP), the most toxic congener in unsubstituted PAHs, and depositions across the Arctic subject to global trade and industry relocation. We show that interregional trade and industry relocation dramatically reduce the atmospheric levels and deposition of BaP in the Arctic. The most significant BaP decline occurs in the European and North American Arctic regions due to attenuated sources in the two well-developed continents proximate to the polar region induced by the relocation of high-PAH pollution industries to many developing countries far from the Arctic. Although BaP emissions embodied in industry relocations in China, India, and South and Southeast Asia resulted in increased BaP contamination in the Asian Arctic, such increases in pollution are minor compared to significant BaP reductions occurring in the European and North American Arctic regions. We find that "North-to-South" industry transfer could reduce trade-related BaP contamination by 60% in the Arctic.
Assuntos
Poluentes Atmosféricos , Hidrocarbonetos Policíclicos Aromáticos , Poluentes Atmosféricos/análise , Regiões Árticas , Monitoramento Ambiental/métodos , Internacionalidade , Hidrocarbonetos Policíclicos Aromáticos/análiseRESUMO
BACKGROUND: Using agricultural wastes to produce single-cell proteins (SCP) can reduce production costs effectively. The aims of this study were to investigate the effects of enzyme loading on the components of rice straw (RS) hydrolysate and their effects on the growth of yeast. RESULTS: At the same glucose concentration, the dry weight of cells produced in the hydrolysate was 2.89 times higher than that in 2 g L-1 yeast extract (YE) medium, indicating that the hydrolysate was a suitable substrate for yeast growth. Ethanol precipitation followed by analysis showed that there were many oligosaccharides in the hydrolysate. The amount of cellulase had an important effect on the production of monosaccharides but had a smaller effect on the amounts and compositions of oligosaccharides. Adding oligosaccharides to the medium had no effect on ethanol production, but it promoted yeast growth and increased SCP production effectively. The results indicate that oligosaccharides were an important growth factor for yeast in the hydrolysate. Compared with YE medium, the cost of the medium with the hydrolysate was reduced by 68.47% when the same dry cell weight was obtained. CONCLUSION: Oligosaccharides in the hydrolysate can improve SCP production with low nutrient cost. This finding could reduce the amounts of cellulase required during saccharification and nutrients during culture, providing a new low-cost method for SCP production. © 2021 Society of Chemical Industry.
Assuntos
Celulase , Oryza , Celulase/metabolismo , Meios de Cultura/metabolismo , Etanol/metabolismo , Fermentação , Hidrólise , Oligossacarídeos/metabolismo , Oligossacarídeos/farmacologia , Oryza/química , Saccharomyces cerevisiae/metabolismoRESUMO
Porcine reproductive and respiratory syndrome virus (PRRSV) isolates show high genetic and pathogenic diversity. The mechanisms underlying different virulence of PRRSV isolates are still not fully clarified. Two highly homologous PRRSV isolates (XJ17-5 and JSTZ1712-12) with distinct virulence were identified in our previous study. To evaluate the association between host responses and different virulence, here we investigated the transcriptomic profiles of porcine alveolar macrophages (PAMs) infected with these two isolates. RNA-Seq results showed that there are 1932 differential expression genes (DEGs) between two PRRSV infected groups containing 1067 upregulation and 865 downregulation genes. Compared with the avirulent JSTZ1712-12 infected group, GO analysis identified significant enrichment gene sets not only associated with virus infection but also innate immune response in the virulent XJ17-5 infected group. In addition, KEGG analysis indicated significantly enriched genes associated with NOD-like and RIG-I-like receptor signaling pathways in XJ17-5 vs JSTZ1712-12 group. Furthermore, XJ17-5 isolate induced significantly higher levels of innate immune response associated genes (IL-1ß, CXCL2, S100A8, OAS2, MX1, IFITM3, ISG15 and IFI6) than JSTZ1712-12 isolate, which were further confirmed by real-time PCR. Given that these two isolates share similar replication efficiency in vivo and in vitro, our results indicated that distinct virulence of PRRSV isolates is associated with different host innate immune responses.
Assuntos
Síndrome Respiratória e Reprodutiva Suína , Vírus da Síndrome Respiratória e Reprodutiva Suína , Animais , Imunidade Inata , Macrófagos Alveolares , Vírus da Síndrome Respiratória e Reprodutiva Suína/genética , Suínos , Transcriptoma , VirulênciaRESUMO
Due to the substantial genetic diversity of porcine reproductive and respiratory syndrome virus (PRRSV), commercial PRRS vaccines fail to provide sufficient cross protection. Previous studies have confirmed the existence of PRRSV broadly neutralizing antibodies (bnAbs). However, bnAbs are rarely induced by either natural infection or vaccination. In this study, we designed and synthesized a consensus sequence of PRRSV2 ORF2-6 genes (ORF2-6-CON) encoding all envelope proteins based on 30 representative Chinese PRRSV isolates. The ORF2-6-CON sequence shared > 90% nucleotide identities to all four lineages of PRRSV2 isolates in China. A chimeric virus (rJS-ORF2-6-CON) containing the ORF2-6-CON was generated using the avirulent HP-PRRSV2 JSTZ1712-12 infectious clone as a backbone. The rJS-ORF2-6-CON has similar replication efficiency as the backbone virus in vitro. Furthermore, pig inoculation and challenge studies showed that rJS-ORF2-6-CON is not pathogenic to piglets and confers better cross protection against the virulent NADC30-like isolate than a commercial HP-PRRS modified live virus (MLV) vaccine. Noticeably, the rJS-ORF2-6-CON strain could induce bnAbs while the MLV strain only induced homologous nAbs. In addition, the lineages of VDJ repertoires potentially associated with distinct nAbs were also characterized. Overall, our results demonstrate that rJS-ORF2-6-CON is a promising candidate for the development of a PRRS genetic engineered vaccine conferring cross protection.
Assuntos
Anticorpos Amplamente Neutralizantes/imunologia , Proteção Cruzada/imunologia , Fases de Leitura Aberta , Síndrome Respiratória e Reprodutiva Suína/imunologia , Vírus da Síndrome Respiratória e Reprodutiva Suína/imunologia , Animais , Anticorpos Amplamente Neutralizantes/genética , Sequência Consenso , Vírus da Síndrome Respiratória e Reprodutiva Suína/genética , Vírus da Síndrome Respiratória e Reprodutiva Suína/patogenicidade , Sus scrofa , Suínos , VirulênciaRESUMO
Rural residential energy switching from solid fuels to electricity and natural gas has resulted in substantial health benefits in China. Here, we quantitatively estimated the environmental and health benefits of stove upgrading, energy switching, and the interaction of stove upgrading and energy switching in rural mainland China during the period of 1980-2014. Driven by government intervention, technical progress, and socioeconomic development, domestic stoves have been upgraded from a domination of open-fire and traditional stoves to energy-saving, clean stoves, and gas range/electric stoves. Furthermore, stove upgrading significantly contributed to the overall reductions in PM2.5 emissions (25%), ambient and indoor PM2.5 concentrations (49 and 28%), population exposure (31%), and premature deaths (37%) attributable to residential emissions. The interaction between stove upgrading and energy switching resulted in an additional 15% reduction in premature deaths. The influences of the residential sector and the beneficial effects of stove upgrading and energy switching are magnified along the causal path from emissions to health impacts. The overall benefit of the transition in residential energy would be substantially underestimated without considering stove upgrading.
Assuntos
Poluentes Atmosféricos , Poluição do Ar em Ambientes Fechados , Utensílios Domésticos , Poluentes Atmosféricos/análise , Poluição do Ar em Ambientes Fechados/análise , China , Culinária , Humanos , Material Particulado/análise , População RuralRESUMO
This study investigated the performance of an autohydrogenotrophic membrane biofilm reactor (MBfR) to remove nitrate from water with high sulfate concentrations. The results of simulated running showed that TN removal could be over than 98.8% with the maximum denitrification rate of 134.6 g N/m3 d under the conditions of the influent sulfate concentrations of 300 mg SO42-/l. The distribution ratio of H2 electron donor for nitrate and sulfate was 70.0 : 26.9 at the high influent loading ratio of sulfate/nitrate of 853.3 g SO42-/m3 d : 140.5 g N/m3 d, which indicated that denitrification bacteria (DB) were normally dominated to complete H2 electron with sulfate bacteria (SRB). The results of molecular microbiology analysis showed that the dominated DB were Rhodocyclus and Hydrogenophaga, and the dominated SRB was Desulfohalobium, under the high influent sulfate concentrations.
Assuntos
Biofilmes/crescimento & desenvolvimento , Reatores Biológicos/microbiologia , Desnitrificação , Hidrogênio/metabolismo , Nitratos/metabolismo , Águas Residuárias , Purificação da Água/métodos , Bactérias/classificação , Bactérias/genética , Biota , Membranas/microbiologia , Sulfatos/análise , Poluentes Químicos da Água/metabolismoRESUMO
Riemerella anatipestifer (RA) is the causative agent of infectious serositis in ducklings and other avian species. It is difficult to control the disease due to its 21 serotypes, poor cross-protection, and bacterial resistance to antimicrobial agents. The complement system is an important component of the innate immune system. However, bacterial pathogens exploit several strategies to evade detection by the complement system. Here, we purified and identified a 59-kDa RA extracellular protease S (EcpS) consisting of a gelatinase. In this study, we aimed to determine how EcpS interferes with complement activation and whether it could block complement-dependent neutrophil function. We found that EcpS potently blocked RA phagocytosis and killing by duck neutrophils. Furthermore, EcpS inhibited the opsonization of bacteria by complement 3b. EcpS specifically blocked complement 3b and complement 4b deposition via the classical and lectin pathways, whereas the alternative pathway was not affected. In summary, we show that RA can survive the bactericidal activity of the duck complement system. These results indicate that RA has evolved mechanisms to evade the duck complement system that may increase the efficiency by which this pathogen can gain access and colonize the inner tissues where it may cause severe infections.
Assuntos
Ativação do Complemento/efeitos dos fármacos , Proteínas do Sistema Complemento/metabolismo , Patos , Endopeptidases/metabolismo , Riemerella/enzimologia , Animais , Proteínas de Bactérias/imunologia , Endopeptidases/genética , Infecções por Flavobacteriaceae/imunologia , Infecções por Flavobacteriaceae/microbiologia , Infecções por Flavobacteriaceae/veterinária , Doenças das Aves Domésticas/microbiologia , SoroRESUMO
Competing reaction mechanisms, substituent effects, and regioselectivities of Ni(PPh3)2-catalyzed [2 + 2 + 2] carboryne-alkyne cycloadditions were characterized by density functional theory using the real chemical systems and solvent effects considered. A putative mechanism involving the following steps was characterized: (1) exothermic carboryne-catalyst complexation and nucleophilic attack by the first alkyne; (2) insertion of the second alkyne, the rate-determining step (RDS) in all four reactions studied; (3) isomerization of reactant-bound complexes; and (4) product elimination and catalyst regeneration. The RDS in three reactions is mediated by free energy barriers of 27.2, 31.1, and 36.6 kcal·mol(-1), representative of the corresponding experimental yields of 67, 54, and 33%, respectively. A fourth reaction with 0% experimental yield showed representative RDS free energy barriers of 60.4 kcal·mol(-1), which are difficult to surmount even at 90 °C. Alternative pathways leading to differing isomers were similarly characterized and successfully reproduced experimentally determined product regioselectivities. Kinetic data derived from free energy barriers are in quantitative agreement (< ± 0.75-3.0 kcal·mol(-1)) of the experimental times, affirming the theoretical results as representative of the real chemical transformations. Complementary determinations show the use of truncated models (Ni(PMe3)2, Ni(PH3)2) causes the RDS to vary from step 2 (alkyne insertion) to step 1 (alkyne attack), highlighting the need to employ real chemical systems in modeling these reactions.
RESUMO
Emotion is a complex physiological phenomenon, and a single modality may be insufficient for accurately determining human emotional states. This paper proposes an end-to-end multimodal emotion recognition method based on facial expressions and non-contact physiological signals. Facial expression features and remote photoplethysmography (rPPG) signals are extracted from facial video data, and a transformer-based cross-modal attention mechanism (TCMA) is used to learn the correlation between the two modalities. The results show that the accuracy of emotion recognition can be slightly improved by combining facial expressions with accurate rPPG signals. The performance is further improved with the use of TCMA, for which the binary classification accuracy of valence and arousal is 91.11% and 90.00%, respectively. Additionally, when experiments are conducted using the whole dataset, an increased accuracy of 7.31% and 4.23% for the binary classification of valence and arousal, and an improved accuracy of 5.36% for the four classifications of valence-arousal are achieved when TCMA is used in modal fusion, compared to using only facial expression modality, which fully demonstrates the effectiveness and robustness of TCMA. This method makes it possible to realize multimodal emotion recognition of facial expressions and contactless physiological signals in reality.
RESUMO
In this study, Polycaprolactone (PCL)/Yam Polysaccharide (YP) fiber membranes loaded the ultrasound-mediated assembly of 2-Hydroxypropyl-ß-cyclodextrin (HP-ß-CD)/Epicatechin gallate (ECG) inclusion complexes were prepared by electrospinning technology for food packaging. Morphology, infrared spectroscopy and X-ray diffraction results showed that the inclusion complexes were successfully assembled. With the addition of inclusion complexes, the average diameter of the fibers increased from 2480.96 to 10179.12 nm, the crystallinity decreased, the thermal stability improved, the hydrophilicity enhanced, and the water vapor permeability enhanced. Meanwhile, thermogravimetry and differential scanning calorimetry results showed that the inclusion complexes formed hydrogen bonds between the fibers, which improved the thermal stability, but the mechanical behavior suffered a certain loss. In addition, the fiber membrane could continuously release ECG within 240 h, which showed excellent antibacterial effects both in vitro and in vivo. These results indicated that the fiber film developed based on electrospinning had a broad application prospect in food packaging.