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Offshore coastal marine ranching ecosystems provide habitat for diverse and active bacterial communities. In this study, 16S rRNA gene sequencing and multiple bioinformatics methods were applied to investigate assembly dynamics and relationships in different habitats. The higher number of edges in the water network, more balanced ratio of positive and negative links, and more keystone species included in the co-occurrence network of water. Stochastic processes dominated in shaping gut and sediment community assembly (R2 < 0.5), while water bacterial community assembly were dominated by deterministic processes (R2 > 0.5). Dissimilarity-overlap curve model indicated that the communities in different habitats have general dynamics and interspecific interaction (P < 0.001). Bacterial source-tracking analysis revealed that the gut was more similar to the sediment than the water bacterial communities. In summary, this study provides basic data for the ecological study of marine ranching through the study of bacterial community dynamics.
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Bactérias , Ecossistema , RNA Ribossômico 16S , Estações do Ano , Bactérias/genética , Bactérias/classificação , Sedimentos Geológicos/microbiologia , Microbiota , Água do Mar/microbiologiaRESUMO
To understand the underlying molecular mechanisms, mouse bone marrow mesenchymal stem cells (BMSCs) and zebrafish embryos were exposed to the control group and Tributyltin (TBT) group (10 ng/L, environmental concentration) for 48 h, respectively. The expression profiles of RNAs were investigated using whole-transcriptome analysis in mouse BMSCs or zebrafish embryos after TBT exposure. For mouse BMSCs, the results showed 2,449 differentially expressed (DE) mRNAs, 59 DE miRNAs, 317 DE lncRNAs, and 15 circRNAs. Similarly, for zebrafish embryos, the results showed 1,511 DE mRNAs, 4 DE miRNAs, 272 DE lncRNAs, and 28 circRNAs. According to KEGG pathway analysis showed that DE RNAs were mainly associated with immune responses, signaling, and cellular interactions. Competing endogenous RNA (ceRNA) network analysis revealed that the regulatory network of miRNA-circRNA constructed in zebrafish embryos was more complex compared to that of mouse BMSCs.
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Células-Tronco Mesenquimais , MicroRNAs , RNA Longo não Codificante , Compostos de Trialquitina , Animais , Camundongos , Peixe-Zebra/metabolismo , RNA Circular/genética , RNA Circular/metabolismo , RNA Longo não Codificante/genética , RNA Longo não Codificante/metabolismo , Perfilação da Expressão Gênica , MicroRNAs/genética , MicroRNAs/metabolismo , RNA Mensageiro/metabolismo , Células-Tronco Mesenquimais/metabolismoRESUMO
The simultaneous presence of micro(nano)plastics (MNPs) and pollutants represents a prevalent environmental challenge that necessitates understanding their combined impact on toxicity. This study examined the distribution of 5 µm (PS-MP5) and 50 nm (PS-NP50) polystyrene plastic particles during the early developmental stages of marine medaka (Oryzias melastigma) and assessed their combined toxicity with triphenyltin (TPT). Results showed that 2 mg/L PS-MP5 and PS-NP50 could adhere to the embryo surface. PS-NP50 can passively enter the larvae and accumulate predominantly in the intestine and head, while PS-MP5 cannot. Nonetheless, both types can be actively ingested by the larvae and distributed in the intestine. 2 mg/L PS-MNPs enhance the acute toxicity of TPT. Interestingly, high concentrations of PS-NP50 (20 mg/L) diminish the acute toxicity of TPT due to their sedimentation properties and interactions with TPT. 200 µg/L PS-MNPs and 200 ng/L TPT affect complement and coagulation cascade pathways and cardiac development of medaka larvae. PS-MNPs exacerbate TPT-induced cardiotoxicity, with PS-NP50 exhibiting stronger effects than PS-MP5, which may be related to the higher adsorption capacity of NPs to TPT and their ability to enter the embryos before hatching. This study elucidates the distribution of MNPs during the early developmental stages of marine medaka and their effects on TPT toxicity, offering a theoretical foundation for the ecological risk assessment of MNPs.
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Compostos Orgânicos de Estanho , Oryzias , Poluentes Químicos da Água , Animais , Cardiotoxicidade , Poluentes Químicos da Água/análise , Poliestirenos/metabolismo , Larva , Plásticos/metabolismoRESUMO
Developing high-efficiency nondoped blue organic light-emitting diodes (OLEDs) with high color purity and low-efficiency roll-off is vital for display and lighting applications. Herein, we developed two asymmetric D-π-A blue emitters, PIAnTP and PyIAnTP, in which triphenylene is first utilized as a functional acceptor. The relatively weak charge transfer (CT) properties, rigid molecular structures, and multiple supramolecular interactions in PIAnTP and PyIAnTP can significantly enhance the fluorescence efficiency and suppress the structural relaxations to obtain a narrowband blue emission. The photophysical experiments and theoretical simulations reveal that they both exhibit a typical hybridized local and charge-transfer (HLCT) excited state and achieve high external quantum efficiency (EQE) via a "hot exciton" channel. As a result, PIAnTP- and PyIAnTP-based nondoped devices realize blue emission at 456 and 464 nm, corresponding to CIE coordinates of (0.16, 0.14) and (0.16, 0.19), narrow full width at half-maximums of 52 and 60 nm, and the high EQEs of 8.36 and 8.69%, respectively. More importantly, the PIAnTP- and PyIAnTP-based nondoped devices show small EQE roll-offs of only 5.9 and 2.4% at 1000 cd m-2, respectively. These results signify an advance in designing a highly efficient blue emitter for nondoped OLEDs.
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The interfacial thermal resistance (ITR) inside the particulate-filled polymer composite is a bottleneck for improving the thermal conductivity (TC) of the material. Getting full knowledge of the ITR is crucial to the material design as well as to a faithful prediction of TC of the composite. However, a method fully taking into account the local circumstances inside the composite is yet to be developed to precisely characterize the ITR. Here, we propose a comprehensive framework combining high-throughput numerical simulations, machine learning and optimization algorithms, and experiments, which is demonstrated to be robust for the accurate determination of ITRs inside the particulate-filled composites. The strategy extracts as much information as possible about the structure and heat transfer characteristics of the composite based on simple experiments, which lays the foundation for the method to be effective. We show that the polymer-filler ITRs and the effective filler-filler contact ITRs predicted with the method faithfully represent the true characteristics inside the composite materials; they also provide the exact effective parameters, which cannot be obtained from experiments, for accurate numerical prediction of TCs of composite materials with high efficiency. As a result, the framework not only provides a robust tool for accurate characterization of ITRs inside composites but also paves the way for virtual high-throughput formula screening of thermally conductive composite materials that could be used in industrial product design.
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Norfloxacin (NOR) is an early third-generation quinolone antibiotic that has been widely used in animal husbandry and aquaculture because of its bactericidal properties. As an emerging contaminant, NOR may have toxic effects on fish. This study assessed the chronic toxicity (6 weeks) of 0 (control group), 100 ng/L (environmental concentration), and 1 mg/L NOR to the gut microbiota of juvenile common carp (Cyprinus carpio) based on metagenomic sequencing. Metagenomic analysis revealed that the Proteobacteria, Bacteroidetes, Fusobacteria, Firmicutes, and Actinobacteria were the dominant bacteria in the gut of common carp. The relative abundance of Actinobacteria was highest in the control group. The alpha diversity of the environmental concentration NOR was significantly lower than the control group. Principal coordinates analysis (PCoA) indicated that the bacterial community between the different groups formed clear separate clusters. NOR exposure adversely could affect immune function and some substance metabolic pathways in the gut microbiota of common carp. Furthermore, environmental concentrations of NOR produce antibiotic resistance genes (ARGs) in the gut microbiota, enhancing resistance to drugs. In conclusion, environmental concentrations of NOR could alter the composition, structure, and abundance of ARGs in the gut microbiota, thereby affecting the intestinal health of fish.
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Carpas , Microbioma Gastrointestinal , Animais , Norfloxacino/toxicidade , Metagenômica , Bactérias/genética , Antibacterianos/toxicidadeRESUMO
The current study was performed to examine the acute toxicity of mercuric chloride (HgCl2) on the silver carp (Hypophthalmichthys molitrix) larvae. Probit analysis was used to determine the median lethal concentration (LC50). The LC50 values of Hg2+ for the fish larvae at 24, 48, 72, and 96 h were 267.72, 252.97, 225.57, and 97.80 µg/L, respectively. The safe concentration of Hg was 9.78 µg/L for fish larvae. Based on the 96 h LC50, fish were exposed to four different groups including 0, 6.11, 12.23, and 24.45 µg/L for 96 h to assess the effects of different concentrations of Hg2+ on antioxidant capacity, energy metabolism parameters, and related gene expression. The findings revealed that there were no significant differences in the activities of superoxide dismutase (SOD) and total antioxidant capacity (T-AOC) in fish larvae among all the groups (P < 0.05). In the 12.23 µg/L group, fish larvae had a maximum in catalase (CAT) activity. The creatine kinase (CK) activities of fish larvae in control and 6.11 µg/L groups were significantly lower than those groups (P < 0.05). A high concentration of Hg2+ significantly upregulated the mRNA levels of heat shock protein 70 (HSP70) and metallothionein (MT) genes in fish larvae. Furthermore, the IBR index value showed the highest value in the 24.45 µg/L group. Overall, this study provides an increased understanding of the effects of Hg-acute toxicity on silver carp larvae.
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Carpas , Mercúrio , Animais , Antioxidantes/metabolismo , Carpas/metabolismo , Larva , Superóxido Dismutase/metabolismo , Mercúrio/metabolismoRESUMO
DCOIT (4,5-dichloro-2-n-octyl-4-isothiazolin-3-one) is the main ingredient in SeaNine-211, a new antifouling agent that replaces organotin compounds to prevent the growth of fouling organisms on board. Biocides from antifoulants can cause problems for marine ecosystems by destroying non-target algal species. This study evaluated the potential adverse effects DCOIT using the Marine Chlorella sp. The concentration of DCOIT were set according to the semi-inhibitory concentrations for acute exposure experiments, and relevant oxidative stress indicators were measured to assess the acute toxic effects. The results showed that the inhibition concentrations (IC50) of DCOIT against Marine Chlorella sp was 2.522 mg/L. The genes related to photosynthesis and antioxidant capacity showed the effect of promoting low concentration and inhibiting high concentration. In addition, based on the ultrastructural observation and the expression analysis of photosynthesis related genes, it was found that DCOIT had a significant effect on plant photosynthesis.
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Incrustação Biológica , Chlorella , Poluentes Químicos da Água , Poluentes Químicos da Água/toxicidade , Incrustação Biológica/prevenção & controle , Ecossistema , Tiazóis/toxicidadeRESUMO
The rise of "new" sequencing technologies and the development of sophisticated bioinformatics tools have dramatically increased the study of the aquaculture microbiome. Microbial communities exist in complex and dynamic communities that play a vital role in the stability of healthy ecosystems. The gut microbiome contributes to multiple aspects of the host's physiological health status, ranging from nutritional regulation to immune modulation. Although studies of the gut microbiome in aquaculture are growing rapidly, the interrelationships between the aquaculture microbiome and its aquatic environment have not been discussed and summarized. In particular, few reviews have focused on the potential mechanisms driving the alteration of the gut microbiome by surrounding aquatic environmental factors. Here, we review current knowledge on the host gut microbiome and its interrelationship with the microbiome of the surrounding environment, mainly including the main methods for characterizing the gut microbiome, the composition and function of microbial communities, the dynamics of microbial interactions, and the relationship between the gut microbiome and the surrounding water/sediment microbiome. Our review highlights two potential mechanisms for how surrounding aquatic environmental factors drive the gut microbiome. This may deepen the understanding of the interactions between the microbiome and environmental factors. Lastly, we also briefly describe the research gaps in current knowledge and prospects for the future orientation of research. This review provides a framework for studying the complex relationship between the host gut microbiome and environmental stresses to better facilitate the widespread application of microbiome technologies in fisheries and aquaculture.
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Microbioma Gastrointestinal , Microbiota , Aquicultura , PesqueirosRESUMO
Polystyrene (PS) is one of the most dangerous polymers, mainly because of the mutagenic or carcinogenic risk of the monomers used to produce it. Sea-Nine 211 is a commercial antifouling agent; its active ingredient is the biocide 4,5-dichloro-2-octyl-4-isothiazolinone-3-one (DCOIT). Micro- and nano-plastics have different synergistic effects on marine organisms together with organic pollutants. To understand the toxic effects of DCOIT and PS alone and in combination, marine Chlorella sp was selected as the experimental organism. The exposure concentration of DCOIT was set at 50 µg/L, and that of PS was set at 10 µg/L. The results show that all exposed groups promoted the growth of marine Chlorella sp in the late stage of exposure, and the recovery time of marine Chlorella sp in the exposed group containing PS was earlier. Changing trend of chlorophyll a was consistent with the growth trend. On the 15th day of exposure, the gene expression of the photosynthesis system in the combined exposed group showed a significant difference, and the cells produced oxidative stress. Scanning electron microscope observation shows the algae adhered to each other. The volume of algae cells in DCOIT and PS exposed groups decreased, and the internal structure of algae cells in each exposed group was damaged.
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Chlorella , Poluentes Químicos da Água , Clorofila A/farmacologia , Microplásticos/toxicidade , Poliestirenos/toxicidade , Poluentes Químicos da Água/toxicidadeRESUMO
This study aimed to determine the effects of Enrofloxacin (ENR) exposure and depuration on the disruption of thyroid function and growth of juvenile grass carp (Ctenopharyngodon idella) as well as to assess the risk of ENR exposure to human health. Juvenile grass carp were treated with ENR solutions at different concentration gradients for 21 days and then depurated for 14 days. The results indicated ENR accumulation in the juvenile grass carp muscles, which persisted after depuration. In addition, exposure to ENR could alter growth by regulating the expression of genes associated with growth hormone/insulin-like growth factor (GH)/IGF) axis and the hypothalamic-pituitary-thyroid (HPT) axis. During ENR exposure, no significant changes in growth hormone levels were observed; however, a significant increase in the growth hormone level was noted. GH/IGF axis-related genes were upregulated after ENR exposure, and their expression levels remained high after depuration. Notably, a significant increase in the serum triiodothyronine (T3) and thyroxine (T4) levels coincided with the upregulation of HPT axis-related genes in both exposure and depuration treatments, and their expression levels remained high after depuration. Therefore, juvenile grass carp exposure to ENR induces physiological stress through HPT and GH/IGF axes that cannot be recovered after depuration. ENR accumulates in the muscles of juvenile grass carp and may pose a threat to human health. Therefore, exposure of juvenile grass carp to ENR results in impaired thyroid function and impaired growth. In addition, consumption of ENR-exposed fish poses human health risks.
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Carpas , Animais , Carpas/metabolismo , Enrofloxacina/toxicidade , Proteínas de Peixes/genética , Hormônio do Crescimento/genética , Hormônio do Crescimento/metabolismo , Tiroxina , Tri-IodotironinaRESUMO
In this study, Chinese rare minnow (Gobiocypris rarus) larvae were exposed to the control group, Cd concentrations (0.5 and 2.5 mg/L), and Hg concentrations (0.1 and 0.3 mg/L) for 96 h. Transcriptome analysis showed that 816 and 1599 significantly differentially expressed genes (DEGs) were identified in response to 2.5 mg/L Cd2+ and 0.3 mg/L Hg2+, respectively. Functional enrichment analysis revealed that DEGs were mostly associated with immune responses after Cd exposure, such as antigen processing and presentation, phagosome, apoptosis, and lysosome. Similarly, functional enrichment analysis showed that many pathways were mostly involved in metabolism after Hg exposure, such as glutathione metabolism and starch and sucrose metabolism. Results of two-dimensional electrophoresis (2-DE) showed that the abundance of 10 protein spots was significantly altered in the Cd2+ treatments. The proteomic analysis demonstrated that Cd toxicity might impair cytoskeletal and cell motility-related protein activity in the liver of G. rarus. Similarly, the abundance of 24 protein spots was significantly altered in the Hg2+ treatments. Hg toxicity regulates the expression of proteins belonging to several functional categories, including cytoskeleton, oxidative stress, digestive system, and energy metabolism. This study provides valuable relevant insight into the molecular mechanisms in response to Cd or Hg toxicity in aquatic organisms and will help screen for potential biomarkers to respond to Cd and Hg pollutants.
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Cyprinidae , Mercúrio , Poluentes Químicos da Água , Animais , Cádmio/metabolismo , Cádmio/toxicidade , China , Cyprinidae/metabolismo , Larva , Mercúrio/metabolismo , Mercúrio/toxicidade , Proteômica , Transcriptoma , Poluentes Químicos da Água/toxicidadeRESUMO
Multiple resonance thermally activated delayed fluorescence (MR-TADF) emitters show great potentials for high color purity organic light-emitting diodes (OLEDs). However, the simultaneous realization of high photoluminescence quantum yield (PLQY) and high reverse intersystem crossing rate (kRISC ) is still a formidable challenge. Herein, a novel asymmetric MR-TADF emitter (2Cz-PTZ-BN) is designed that fully inherits the high PLQY and large kRISC values of the properly selected parent molecules. The resonating extended π-skeleton with peripheral protection can achieve a high PLQY of 96 % and a fast kRISC of above 1.0×105 â s-1 , and boost the performance of corresponding pure green devices with an outstanding external quantum efficiency (EQE) of up to 32.8 % without utilizing any sensitizing hosts. Remarkably, the device sufficiently maintains a high EQE exceeding 23 % at a high luminance of 1000â cd m-2 , representing the highest value for reported green MR-TADF materials at the same luminescence.
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Multi-resonance thermally activated delayed fluorescence (MR-TADF) material, which possesses the ability to achieve narrowband emission in organic light-emitting diodes (OLEDs), is of significant importance for wide color gamut and high-resolution display applications. To date, MR-TADF material with narrow full width at half-maximum (FWHM) below 0.14 eV still remains a great challenge. Herein, through peripheral protection of MR framework by phenyl derivatives, four efficient narrowband MR-TADF emitters are successfully designed and synthesized. The introduction of peripheral phenyl-based moieties via a single bond significantly suppresses the high-frequency stretching vibrations and reduces the reorganization energies, accordingly deriving the resulting molecules with small FWMH values around 20 nm/0.11 eV and fast radiative decay rates exceeding 108 s-1 . The corresponding green OLED based on TPh-BN realizes excellent performance with the maximum external quantum efficiency (EQE) up to 28.9% without utilizing any sensitizing host and a relatively narrow FWHM of 0.14 eV (28 nm), which is smaller than the reported green MR-TADF molecules in current literatures. Especially, the devices show significantly reduced efficiency roll-off and relatively long operational lifetimes among the sensitizer-free MR-TADF devices. These results clearly indicate the promise of this design strategy for highly efficient OLEDs with ultra-high color purity.
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Carbon black (CB) has been demonstrated to have adverse effects on the lung tissue. Few studies explored the effects of CB on the cerebellum, widely recognized to contribute to gait and balance coordination and timing in the motor domain. Some studies have reported that inflammatory response and damaged autophagy are important mechanisms of CB toxicity and can be repaired after the recovery. The present study aimed to determine whether long-term CB exposure could induce the inflammation and damaged autophagy of the cerebellum. The rats were randomly divided into four groups. The control group received the filtered air for 90 days; the carbon black (CB) group received CB particles for 90 days; the recovery (R) group received CB for 90 days and recovered for another 14 days; the recovery control (RC) group received filtered air for 104 days. The purpose of the R group was to test whether neuroinflammation and autophagy could be repaired after short-term recovery. The western blot and immunohistochemistry revealed that long-term CB exposure induced augmented level of pro-inflammatory cytokines (Interleukin-1ß, IL-1ß; Interleukin-6, IL-6; and Tumor Necrosis Factor-α, TNF-α) and anti-inflammatory cytokine (Interleukin-10, IL-10). The autophagic markers (Beclin1 and LC3) were increased in both CB group and R group. These findings clearly demonstrated that long-term CB exposure induced inflammation and autophagy in the cerebellum, which were not obviously improved after short-term recovery.
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Autofagia/efeitos dos fármacos , Cerebelo/efeitos dos fármacos , Doenças Neuroinflamatórias/induzido quimicamente , Fuligem/toxicidade , Animais , Western Blotting , Cerebelo/patologia , Masculino , Doenças Neuroinflamatórias/patologia , Ratos , Ratos Sprague-Dawley , Fuligem/administração & dosagemRESUMO
Producing a desirable adsorbent for removing endocrine disrupting compounds (EDCs) from aqueous solutions remains a major challenge. In this work, microporous-dominated nitrogen-doped framework carbons (MNFCs, s means the calcination temperature) with high specific surface area, ultra-microporous structure, and high nitrogen-doping can be obtained by a direct calcination of ethylene diamine tetraacetic acid tetrasodium (EDTA-4Na) without aid of any catalyst and nitrogen source. MNFCs were applied adsorbents to remove bisphenols from aqueous solution. Batch experiments showed MNFC-750 had a large adsorption capacity for bisphenols from aqueous solutions (409 mg/g for bisphenol A, 364 mg/g for bisphenol F, and 521 mg/g for bisphenol S) along with short equilibrium time (30 min), and good stability and reusability. Using multiple characterizations and comparative experiments along with theoretical calculations, we discovered that: (1) nitrogen-doping can significantly boost the adsorption capacity; (2) adsorption sites are mainly the pyridinic-N instead of pyrrolic-N and graphitic-N; and (3) the adsorption mechanisms were mainly driven by Lewis acid-base interaction, hydrophobic interaction, π-π interaction and hydrogen bond interaction. These findings indicate that MNFCs present a promising potential for practical applications and shed light on the rational design of nitrogen doped carbon-based adsorbents for efficient pollutant removal.
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Objective:To explore the clinical effect of Pingchuan Decoction combined with routine western medicine therapy in the treatment of acute attack of bronchial asthma in children. Methods:From January 2017 to June 2019, 118 children with acute attack of bronchial asthma were selected from the Seventh People’s Hospital Affiliated to Shanghai University of Traditional Chinese Medicine, and they were randomly divided into control group (59 cases) and observation group (59 cases) according to the random number table. The control group was treated with routine western medicine therapy, and the observation group was treated with Pingchuan Decoction on the base of control group, and both groups were treated for 14 days. The main symptom scores before and after treatment were evaluated. The percentage of forced vital capacity expressed as percent predicted (FVC% pred) and the forced expiratory volume in 1 second expressed as percent predicted (FEV1% pred) were measured by pulmonary function meter. The levels of CD3 +, CD4 + and CD4 +/CD8 + in peripheral blood were detected by flow cytometry. The adverse reactions during the treatment were recorded and the clinical efficacy was evaluated. Results:The total clinical effective rate was 93.2% (55/59) in the observation group and 71.2% (42/59) in the control group, where the difference between the two groups was statistically significant ( χ2=9.790, P=0.002). After treatment, the scores of cough, wheezing and wheezing rale in the observation group were significantly lower than those in the control group ( t=27.695, 17.573, 32.827, P<0.001). After treatment, FVC% pred [(80.21 ± 4.06)% vs. (71.71 ± 3.95)%, t=11.526], FEV1% pred [(78.84±3.92)% vs. (72.26 ± 3.59)%, t=9.508] in the observation group were significantly higher than those in the control group ( P<0.01). The levels of CD3 + [(74.05 ± 5.13)% vs. (67.44 ± 4.98)%, t=7.101], CD4 + [(48.43 ± 4.31)% vs. (42.20 ± 4.06)%, t=8.082] and the ratio of CD4 +/CD8 + (1.67 ± 0.29 vs. 1.34 ± 0.25, t=6.620) in the observation group were significantly higher than those in the control group ( P<0.01). During the treatment, the incidence of adverse reactions was 10.2% (6/59) in the observation group and 6.8% (4/59) in the control group, and there was no significant difference between the two groups ( χ2=0.437, P=0.509). Conclusion:The Pingchuan Decoction combined with routine western medicine therapy can reduce the clinical symptoms of children with acute attack of bronchial asthma, improve lung function, improve organism immunity and clinical effect with safety.
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Particle morphology is of great significance to the grain- and macro-scale behaviors of granular soils. Most existing traditional morphology descriptors have three perennial limitations, i.e., dissensus of definition, inter-scale effect, and surface roughness heterogeneity, which limit the accurate representation of particle morphology. The inter-scale effect refers to the inaccurate representation of the morphological features at the target relative length scale (RLS, i.e., length scale with respective to particle size) caused by the inclusion of additional morphological details existing at other RLS. To effectively eliminate the inter-scale effect and reflect surface roughness heterogeneity, a novel spherical harmonic-based multi-scale morphology descriptor Rinc is proposed to depict the incremental morphology variation (IMV) at different RLS. The following conclusions were drawn: (1) the IMV at each RLS decreases with decreasing RLS while the corresponding particle surface is, in general, getting rougher; (2) artificial neural network (ANN)-based mean impact values (MIVs) of Rinc at different RLS are calculated and the results prove the effective elimination of inter-scale effects by using Rinc; (3) Rinc shows a positive correlation with the rate of increase of surface area RSA at all RLS; (4) Rinc can be utilized to quantify the irregularity and roughness; (5) the surface morphology of a given particle shows different morphology variation in different sections, as well as different variation trends at different RLS. With the capability of eliminating the existing limitations of traditional morphology descriptors, the novel multi-scale descriptor proposed in this paper is very suitable for acting as a morphological gene to represent the multi-scale feature of particle morphology.
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The rapid development of X-ray imaging techniques with image processing and analysis skills has enabled the acquisition of CT images of granular soils with high-spatial resolutions. Based on such CT images, grain-scale mechanical behavior such as particle kinematics (i.e., particle translations and particle rotations), strain localization and inter-particle contact evolution of granular soils can be quantitatively investigated. However, this is inaccessible using conventional experimental methods. This study demonstrates the exploration of the grain-scale mechanical behavior of a granular soil sample under triaxial compression using synchrotron X-ray micro-tomography (µCT). With this method, a specially fabricated miniature loading apparatus is used to apply confining and axial stresses to the sample during the triaxial test. The apparatus is fitted into a synchrotron X-ray tomography setup so that high-spatial resolution CT images of the sample can be collected at different loading stages of the test without any disturbance to the sample. With the capability of extracting information at the macro scale (e.g., sample boundary stresses and strains from the triaxial apparatus setup) and the grain scale (e.g., grain movements and contact interactions from the CT images), this procedure provides an effective methodology to investigate the multi-scale mechanics of granular soils.
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Solo/química , Síncrotrons/normas , Microtomografia por Raio-X/métodosRESUMO
Objective To investigate the clinical phenotype and molecular diagnosis of Noonan syndrome (NS) caused by mutations in SHOC2 gene. Methods The clinical data and gene testing results of one child with NS were analyzed retrospectively. Results This is an 8-month-old infant. Since birth, the boy had feeding and sleeping difficulties, irritability, and growth retardation. The boy had large head circumference, sparse, thin and yellow hair, broad and prominent forehead, flat nose, slightly wide eye distance, and slightly bilateral eye fissure outward tilt, no eyelid ptosis. Echocardiography showed patent foramen ovale,ventricular septum and left ventricular hypertrophy.A novel mutation(De novo)was found in the SHOC2 gene, heterozygous missense mutation c.4A>G, p.Ser2Gly His parents were normal genotypes. According to the clinical characteristics, relevant literature was reviewed. The clinical manifestation of sleep difficulty has not been reported in the NS patients with SHOC2 mutation.Conclusions This is the first domestic reported NS case with SHOC2 mutation.The phenotype is consistent with the foreign reports.Sleep difficulty may be a new phenotype of NS with SHOC2 mutation.