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1.
RSC Adv ; 12(7): 4234-4239, 2022 Jan 28.
Artigo em Inglês | MEDLINE | ID: mdl-35425439

RESUMO

To obtain high thermostable materials for flexible display substrates, a series of copoly(benzimidazole imide)s was prepared using 5-amine-2-(4-aminobenzene)-1-phenyl-benzimidazole (N-PhPABZ) and 6(5)-amino-2-(4-aminobenzene)-benzimidazole (PABZ). Incorporating N-phenyl groups effectively healed the brittleness of the poly(benzimidazole imide)s (PBIIs) derived from pyromellitic dianhydride (PMDA), and the resultant homo- and copoly(benzimidazole imide)s displayed an outstandingly high glass transition temperature (T g > 450 °C) and a low coefficient of thermal expansion (CTE < 10 ppm K-1). Furthermore, the influence of removing intermolecular hydrogen bonds on the properties of these poly(benzimidazole imide)s was systematically analyzed. These data provide a feasible method to prepare superheat-resistant poly(benzimidazole imide)s without H-bonding.

2.
Cancer Cell Int ; 22(1): 158, 2022 Apr 19.
Artigo em Inglês | MEDLINE | ID: mdl-35440048

RESUMO

BACKGROUND: Several nervous and nerve-related biomarkers have been detected in colorectal cancer (CRC) and can contribute to the progression of CRC. However, the role of leucine-rich repeat neuronal 4 (LRRN4), a recently identified neurogenic marker, in CRC remains unclear. METHODS: We examined the expression and clinical outcomes of LRRN4 in CRC from TCGA-COREAD mRNA-sequencing datasets and immunohistochemistry in a Chinese cohort. Furthermore, colony formation, flow cytometry, wound healing assays and mouse xenograft models were used to investigate the biological significance of LRRN4 in CRC cell lines with LRRN4 knockdown or overexpression in vitro and in vivo. In addition, weighted coexpression network analysis, DAVID and western blot analysis were used to explore the potential molecular mechanism. RESULTS: We provide the first evidence that LRRN4 expression, at both the mRNA and protein levels, was remarkably high in CRC compared to controls and positively correlated with the clinical outcome of CRC patients. Specifically, LRRN4 was an independent prognostic factor for progression-free survival and overall survival in CRC patients. Further functional experiments showed that LRRN4 promoted cell proliferation, cell DNA synthesis and cell migration and inhibited apoptosis. Knockdown of LRRN4 can correspondingly decrease these effects in vitro and can significantly suppress the growth of xenografts. Several biological functions and signaling pathways were regulated by LRRN4, including proteoglycans in cancer, glutamatergic synapse, Ras, MAPK and PI3K. LRRN4 knockdown resulted in downregulation of Akt, p-Akt, ERK1/2 and p-ERK1/2, the downstream of the Ras/MAPK signaling pathway, overexpression of LRRN4 leaded to the upregulation of these proteins. CONCLUSIONS: Our results suggest that LRRN4 could be a biological and molecular determinant to stratify CRC patients into distinct risk categories, and mechanistically, this is likely attributable to LRRN4 regulating several malignant phenotypes of neoplastic cells via RAS/MAPK signal pathways.

3.
J Supercomput ; : 1-20, 2022 Apr 09.
Artigo em Inglês | MEDLINE | ID: mdl-35431451

RESUMO

Aspect-level sentiment classification has been widely used by researchers as a fine-grained sentiment classification task to predict the sentiment polarity of specific aspect words in a given sentence. Previous studies have shown relatively good experimental results using graph convolutional networks, so more and more approaches are beginning to exploit sentence structure information for this task. However, these methods do not link aspect word and context well. To address this problem, we propose a method that utilizes a hierarchical multi-head attention mechanism and a graph convolutional network (MHAGCN). It fully considers syntactic dependencies and combines semantic information to achieve interaction between aspect words and context. To fully validate the effectiveness of the method proposed in this paper, we conduct extensive experiments on three benchmark datasets, which, according to the experimental results, show that the method outperforms current methods.

4.
Scand J Immunol ; : e13177, 2022 Apr 28.
Artigo em Inglês | MEDLINE | ID: mdl-35484925

RESUMO

Chrysin (CHR) is a flavonoid with extensive pharmacological activity. The molecular formula of CHR is C15 H10 O4 . CHR is reported to have antioxidative, antitumour and antiviral functions. To evaluate its potential function as a vaccine adjuvant, we prepared a melanoma vaccine using a soluble protein extract of B16F10 melanoma cells as antigen and CHR as an adjuvant. The melanoma model was developed after two immunizations, and it was discovered that combining B16F10 soluble protein antigen-mixed CHR vaccine could inhibit tumour growth in the mouse model, and the overall survival rate was higher than that of the B16F10 antigen vaccine alone. In vivo and in vitro experiments were conducted to determine whether CHR functioned as an adjuvant by activating antigen-presenting cells (APCs). We discovered that CHR activated APCs both in vivo and in vitro and may enhance Th1 cell function by activating the IL12-STAT4 signal pathway, thereby enhancing the antitumour response of cytotoxic T lymphocytes (CTLs) in vivo. Next, to verify the critical role of CD8+ T cells in suppressing melanoma development, we transplanted CD8+ T cells from immunized mice to B16F10 tumour-bearing mice and discovered that the survival rate of tumour-bearing mice was significantly prolonged. In summary, our experimental results indicate that CHR can be used as a potential adjuvant to enhance antigen immunogenicity, inhibit B16F10 tumour growth in mice and improve tumour immune response.

5.
Cell ; 185(6): 1082-1100.e24, 2022 03 17.
Artigo em Inglês | MEDLINE | ID: mdl-35216674

RESUMO

We assembled a semi-automated reconstruction of L2/3 mouse primary visual cortex from ∼250 × 140 × 90 µm3 of electron microscopic images, including pyramidal and non-pyramidal neurons, astrocytes, microglia, oligodendrocytes and precursors, pericytes, vasculature, nuclei, mitochondria, and synapses. Visual responses of a subset of pyramidal cells are included. The data are publicly available, along with tools for programmatic and three-dimensional interactive access. Brief vignettes illustrate the breadth of potential applications relating structure to function in cortical circuits and neuronal cell biology. Mitochondria and synapse organization are characterized as a function of path length from the soma. Pyramidal connectivity motif frequencies are predicted accurately using a configuration model of random graphs. Pyramidal cells receiving more connections from nearby cells exhibit stronger and more reliable visual responses. Sample code shows data access and analysis.


Assuntos
Neocórtex , Animais , Camundongos , Microscopia Eletrônica , Neocórtex/fisiologia , Organelas , Células Piramidais/fisiologia , Sinapses/fisiologia
6.
Spectrochim Acta A Mol Biomol Spectrosc ; 272: 120991, 2022 May 05.
Artigo em Inglês | MEDLINE | ID: mdl-35182923

RESUMO

Three-dimensional (TD) deoxyribonucleic acid (DNA) tweezers were programmed for one-step identification and detection of ochratoxin A (OTA) and zearalenone (ZEN). The unfolding of the TD-DNA tweezers by aptamers specific to these two mycotoxins "turned" the fluorescent signals "on." The bonding of the aptamers to their corresponding targets in OTA and ZEN "turned" the fluorescent signals and the DNA tweezers "off." The detection limit of the TD-DNA tweezers for OTA and ZEN was 0.032 and 0.037 ng mL-1, respectively. The feasibility of this method was tested using two samples. Detection via this method increased the recovery of OTA and ZEN from 95.8% to 110.2%. Spike recovery and certified food products were used to detect applicability in actual situations. Analyte detection in complex samples using TD-DNA tweezers is rapid, as the process involves a single operational step. This proposed design has considerable potential for application in mycotoxin detection.


Assuntos
Aptâmeros de Nucleotídeos , Zearalenona , DNA , Contaminação de Alimentos/análise , Limite de Detecção , Ocratoxinas , Zearalenona/análise
7.
Immunohorizons ; 6(1): 36-46, 2022 01 17.
Artigo em Inglês | MEDLINE | ID: mdl-35039434

RESUMO

MRL/lpr mice have been extensively used as a murine model of lupus. Disease progression in MRL/lpr mice can differ among animal facilities, suggesting a role for environmental factors. We noted a phenotypic drift of our in-house colony, which was the progeny of mice obtained from The Jackson Laboratory (JAX; stocking number 000485), that involved attenuated glomerulonephritis, increased splenomegaly, and reduced lymphadenopathy. To validate our in-house mice as a model of lupus, we compared these mice with those newly obtained from JAX, which were confirmed to be genetically identical to our in-house mice. Surprisingly, the new JAX mice exhibited a similar phenotypic drift, most notably the attenuation of glomerulonephritis. Interestingly, our in-house colony differed from JAX mice in body weight and kidney size (both sexes), as well as in splenic size, germinal center formation, and level of anti-dsDNA auto-IgG in the circulation (male only). In addition, we noted differential expression of microRNA (miR)-21 and miR-183 that might explain the splenic differences in males. Furthermore, the composition of gut microbiota was different between in-house and new JAX mice at early time points, which might explain some of the renal differences (e.g., kidney size). However, we could not identify the reason for attenuated glomerulonephritis, a shared phenotypic drift between the two colonies. It is likely that this was due to certain changes of environmental factors present in both JAX and our facilities. Taken together, these results suggest a significant phenotypic drift in MRL/lpr mice in both colonies that may require strain recovery from cryopreservation.


Assuntos
Microbioma Gastrointestinal/genética , Nefrite Lúpica/genética , MicroRNAs/genética , Animais , Modelos Animais de Doenças , Feminino , Rim/patologia , Nefrite Lúpica/microbiologia , Nefrite Lúpica/patologia , Masculino , Camundongos , Camundongos Endogâmicos MRL lpr , RNA Ribossômico 16S/análise , Baço/patologia
9.
Mol Biotechnol ; 64(3): 330-337, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-34647243

RESUMO

Lower extremity deep venous thrombosis (LEDVT) is a venous reflux disorder caused by abnormal coagulation of blood. LEDVT can obstruct the lumen and LEDVT is the third vascular disease after cerebrovascular diseases and coronary artery diseases. miRNAs are associated with thrombosis, and miR-185 was reported to affect the proliferation and apoptosis of vascular endothelial cells by regulating receptor of advanced glycation end products (RAGE). However, no study has reported the effect of miR-185 on LEDVT. Here, we studied the effects of miR-185 on the PI3K/AKT and MAPK signaling pathways in the LEDVT cells. The results showed that miR-185 promotes cell proliferation through activating the PI3K/AKT and MAPK signaling pathways and then inhibits tissue factor and fibrin expression to reduce thrombosis. In short, our study provides new ideas and a theoretical basis for research on the prevention, diagnosis, and treatment of LEDVT.


Assuntos
MicroRNAs/genética , Fosfatidilinositol 3-Quinases/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Trombose Venosa/genética , Animais , Proliferação de Células , Células Cultivadas , Cromonas/farmacologia , Modelos Animais de Doenças , Células Endoteliais/citologia , Células Endoteliais/efeitos dos fármacos , Células Endoteliais/metabolismo , Fibrina/metabolismo , Sistema de Sinalização das MAP Quinases , Masculino , Camundongos , Morfolinas/farmacologia , Ratos , Tromboplastina/metabolismo , Trombose Venosa/etiologia , Trombose Venosa/metabolismo
10.
Sci Total Environ ; 807(Pt 2): 151091, 2022 Feb 10.
Artigo em Inglês | MEDLINE | ID: mdl-34688741

RESUMO

Coking plants are a substantial source of potentially toxic elements (PTEs) in soil. In this study, we examined the concentration of PTEs, the soil physicochemical properties, and the Pb isotopes in the soil inside and around a coking plant in an industrial city in northern China. We analyzed the spatial distribution of PTEs and the pollution risk areas by Igeo index, the enrichment factor (EF), and the Nemerow index, and we quantitatively identified the contribution of PTE pollution sources in the soil on a small- and medium-scale (plant and work section). Our results indicated that the Hg concentration inside the plant and the Cd concentration in the agricultural land around the plant were both relatively high. A comprehensive analysis of the soil in the study area was performed using the positive matrix factorization model and Pb isotope (206/207Pb, 208/206Pb) tracing method, based on the MixSIAR model, this analysis indicated that burning coal was the main source of Pb both inside (46.8%) and outside (26.3%) the coking plant. The pollution emission sources with significant influence on the soil outside the coking plant were diesel vehicles (12.5%), gas tanks (12.4%), and coke ovens (11.5%), while the sources inside the plant were quenching sections (11.1%), atmospheric deposition (11.0%), coke oven sections (9.6%), and diesel vehicles (6.1%). The results of PTE pollution risk zoning and Pb isotope tracing indicated that pollution is more serious in the western part of the plant, which is the area where coking and gas production takes place, and the most serious pollution outside the plant is mainly distributed to the southeast. This study provides theoretical and practical data indicating the contribution of industrial enterprises to soil pollution, and will help identify pollution responsibility and the management of pollution sources.


Assuntos
Coque , Solo , China , Planejamento de Cidades
11.
Trends Biotechnol ; 40(5): 620-631, 2022 May.
Artigo em Inglês | MEDLINE | ID: mdl-34666896

RESUMO

Cell fusion is a fundamental biological process that is involved in the development of most eukaryotic organisms. During the fusion process in Saccharomyces cerevisiae, cells respond to pheromones to trigger the MAPK (mitogen-activated protein kinase) cascade to initiate mating, followed by polarization, cell-wall remodeling, membrane fusion, and karyogamy. We highlight the applications of the yeast mating signal pathway in promoter engineering for tuning the expression of output genes, as well as in metabolic engineering for decoupling growth and metabolism, biosensors for sensitive detection and signal amplification, genetic circuits for programmable biological functionalities, and artificial consortia for cell-cell communication. Strategies such as exploiting rational engineering of modular circuits and optimizing the reproductive pathway to precisely maneuver physiological events have implications for scientific research and industrial development.


Assuntos
Proteínas de Saccharomyces cerevisiae , Saccharomyces cerevisiae , Comunicação Celular , Saccharomyces cerevisiae/genética , Saccharomyces cerevisiae/metabolismo , Proteínas de Saccharomyces cerevisiae/genética , Proteínas de Saccharomyces cerevisiae/metabolismo , Transdução de Sinais/genética , Biologia Sintética
12.
Behav Brain Res ; 419: 113683, 2022 02 15.
Artigo em Inglês | MEDLINE | ID: mdl-34838933

RESUMO

Nowadays, there are few studies in vivo to explore the effects of Human Cytomegalovirus (HCMV) single gene such as immediate early protein 2 (IE2) on the nervous system, let alone the mechanism that IE2 causes cognitive impairment. In this study, the Rosa26-LSL-IE2/Cre mouse was used to show the effects of IE2 on the cognitive ability and the GluNRs/CaMKIIα/CREB signaling pathway in the hippocampus. We divided the mice into experimental and control groups based on the results of PCR firstly. After that, the cognitive abilities of the two groups were compared through new object recognition (NOR) and Morris water maze (MWM) tests. The results of the behavioral tests showed that the cognitive ability of the experimental mice was lower than that of the control group. It is known that changes in the expression levels of N-methyl D-aspartate receptor 1, 2A, and 2B (GluN1, GluN2A, GluN2B) affect synaptic plasticity and cause cognitive changes. Finally, we analyzed the expression levels of GluN1, GluN2A, GluN2B, and related signaling pathway molecules by qPCR and western blot. We found that the expression levels of the GluNRs/CaMKIIα/CREB signaling pathway were decreased in the experimental group. These results indicated that IE2 could affect the expression levels of GluNRs/CaMKIIα/CREB signaling pathway, which was closely related to the cognitive impairment of the experimental group. In summary, we used this novel mouse model to show that IE2 could cause cognitive impairment in the hippocampus, which might be related to the GluNRs/CaMKIIα/CREB signaling pathway. It is helpful to further understand the mechanism of the cognitive impairment induced by HCMV IE2.


Assuntos
Proteína Quinase Tipo 2 Dependente de Cálcio-Calmodulina/metabolismo , Disfunção Cognitiva/metabolismo , Proteína de Ligação ao Elemento de Resposta ao AMP Cíclico/metabolismo , Citomegalovirus/genética , Hipocampo/metabolismo , Proteínas Imediatamente Precoces/metabolismo , Receptores de N-Metil-D-Aspartato/metabolismo , Proteínas Virais/metabolismo , Animais , Modelos Animais de Doenças , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Transdução de Sinais/fisiologia
13.
Mol Biol Evol ; 39(2)2022 02 03.
Artigo em Inglês | MEDLINE | ID: mdl-34893856

RESUMO

Domestic sheep and their wild relatives harbor substantial genetic variants that can form the backbone of molecular breeding, but their genome landscapes remain understudied. Here, we present a comprehensive genome resource for wild ovine species, landraces and improved breeds of domestic sheep, comprising high-coverage (∼16.10×) whole genomes of 810 samples from 7 wild species and 158 diverse domestic populations. We detected, in total, ∼121.2 million single nucleotide polymorphisms, ∼61 million of which are novel. Some display significant (P < 0.001) differences in frequency between wild and domestic species, or are private to continent-wide or individual sheep populations. Retained or introgressed wild gene variants in domestic populations have contributed to local adaptation, such as the variation in the HBB associated with plateau adaptation. We identified novel and previously reported targets of selection on morphological and agronomic traits such as stature, horn, tail configuration, and wool fineness. We explored the genetic basis of wool fineness and unveiled a novel mutation (chr25: T7,068,586C) in the 3'-UTR of IRF2BP2 as plausible causal variant for fleece fiber diameter. We reconstructed prehistorical migrations from the Near Eastern domestication center to South-and-Southeast Asia and found two main waves of migrations across the Eurasian Steppe and the Iranian Plateau in the Early and Late Bronze Ages. Our findings refine our understanding of genome variation as shaped by continental migrations, introgression, adaptation, and selection of sheep.


Assuntos
Genoma , Carneiro Doméstico , Animais , Ásia , Europa (Continente) , Variação Genética , Irã (Geográfico) , Polimorfismo de Nucleotídeo Único , Análise de Sequência de DNA , Ovinos/genética , Carneiro Doméstico/genética
14.
Neuroradiology ; 64(3): 503-512, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-34842946

RESUMO

PURPOSE: Development of best practices for dealing with incidental findings on neuroimaging requires insight in their frequency and clinical relevance. METHODS: Here, we delineate prevalence estimates with 95% confidence intervals and clinical management of incidental findings, based on the first 3589 participants of the population-based Rhineland Study (age range 30-95 years) who underwent 3 Tesla structural neuroimaging (3D, 0.8 mm3 isotropic resolution). Two trained raters independently assessed all scans for abnormalities, with confirmation and adjudication where needed by neuroradiologists. Participants were referred for diagnostic work-up depending on the potential benefit. RESULTS: Of 3589 participants (mean age 55 ± 14 years, 2072 women), 867 had at least one possible incidental finding (24.2%). Most common were pituitary abnormalities (12.3%), arachnoid cysts (4.1%), developmental venous anomalies (2.5%), non-acute infarcts (1.8%), cavernomas (1.0%), and meningiomas (0.7%). Forty-six participants were informed about their findings, which was hitherto unknown in 40 of them (1.1%). Of these, in 19 participants (48%), a wait-and-see policy was applied and nine (23%) received treatment, while lesions in the remainder were benign, could not be confirmed, or the participant refused to inform us about their clinical diagnosis. CONCLUSION: Nearly one-quarter of participants had an incidental finding, but only 5% of those required referral, that mostly remained without direct clinical consequences.


Assuntos
Achados Incidentais , Neoplasias Meníngeas , Adulto , Idoso , Idoso de 80 Anos ou mais , Encéfalo/patologia , Estudos Transversais , Feminino , Humanos , Imageamento por Ressonância Magnética/métodos , Masculino , Neoplasias Meníngeas/patologia , Pessoa de Meia-Idade , Neuroimagem/métodos
15.
Dev Comp Immunol ; 129: 104332, 2022 04.
Artigo em Inglês | MEDLINE | ID: mdl-34910945

RESUMO

Zebrafish Fish-egg lectin (zFEL) has been identified and proved to be a maternal factor with antibacterial and opsonic ability in fishes. In this study, we found that zFEL was capable of enhancing the phagocytosis of the bacteria by macrophages of mouse (RAW264.7 and mouse peritoneal macrophages), suggesting a cross-species function of zFEL in higher animals. Further studies showed that zFEL can active the antigen presentation ability by up-regulating the expression of CD80, CD86 and MHC II. Meanwhile, zFEL also promoted the polarization of macrophages to M1-type, which was confirmed by the increase of cytokines TNF-α and IL-6. The expression of p38 gene was up-regulated in macrophages preincubated with zFEL. Taken together, zFEL appears opsonic function in mammal macrophages and has potential application in immunomodulation.


Assuntos
Lectinas/metabolismo , Animais , Antígeno B7-1 , Citocinas/metabolismo , Macrófagos/imunologia , Camundongos , Fagocitose , Fator de Necrose Tumoral alfa/metabolismo , Peixe-Zebra/imunologia
16.
Nat Methods ; 19(1): 119-128, 2022 01.
Artigo em Inglês | MEDLINE | ID: mdl-34949809

RESUMO

Due to advances in automated image acquisition and analysis, whole-brain connectomes with 100,000 or more neurons are on the horizon. Proofreading of whole-brain automated reconstructions will require many person-years of effort, due to the huge volumes of data involved. Here we present FlyWire, an online community for proofreading neural circuits in a Drosophila melanogaster brain and explain how its computational and social structures are organized to scale up to whole-brain connectomics. Browser-based three-dimensional interactive segmentation by collaborative editing of a spatially chunked supervoxel graph makes it possible to distribute proofreading to individuals located virtually anywhere in the world. Information in the edit history is programmatically accessible for a variety of uses such as estimating proofreading accuracy or building incentive systems. An open community accelerates proofreading by recruiting more participants and accelerates scientific discovery by requiring information sharing. We demonstrate how FlyWire enables circuit analysis by reconstructing and analyzing the connectome of mechanosensory neurons.


Assuntos
Encéfalo/fisiologia , Conectoma/métodos , Drosophila melanogaster/fisiologia , Imageamento Tridimensional/métodos , Software , Animais , Encéfalo/citologia , Encéfalo/diagnóstico por imagem , Gráficos por Computador , Visualização de Dados , Drosophila melanogaster/citologia , Neurônios/citologia , Neurônios/fisiologia
17.
Elife ; 102021 12 01.
Artigo em Inglês | MEDLINE | ID: mdl-34851292

RESUMO

Inhibitory neurons in mammalian cortex exhibit diverse physiological, morphological, molecular, and connectivity signatures. While considerable work has measured the average connectivity of several interneuron classes, there remains a fundamental lack of understanding of the connectivity distribution of distinct inhibitory cell types with synaptic resolution, how it relates to properties of target cells, and how it affects function. Here, we used large-scale electron microscopy and functional imaging to address these questions for chandelier cells in layer 2/3 of the mouse visual cortex. With dense reconstructions from electron microscopy, we mapped the complete chandelier input onto 153 pyramidal neurons. We found that synapse number is highly variable across the population and is correlated with several structural features of the target neuron. This variability in the number of axo-axonic ChC synapses is higher than the variability seen in perisomatic inhibition. Biophysical simulations show that the observed pattern of axo-axonic inhibition is particularly effective in controlling excitatory output when excitation and inhibition are co-active. Finally, we measured chandelier cell activity in awake animals using a cell-type-specific calcium imaging approach and saw highly correlated activity across chandelier cells. In the same experiments, in vivo chandelier population activity correlated with pupil dilation, a proxy for arousal. Together, these results suggest that chandelier cells provide a circuit-wide signal whose strength is adjusted relative to the properties of target neurons.


Assuntos
Células Piramidais/ultraestrutura , Sinapses/ultraestrutura , Córtex Visual/ultraestrutura , Animais , Feminino , Masculino , Camundongos , Microscopia Eletrônica de Transmissão
18.
Nanomaterials (Basel) ; 11(11)2021 Nov 03.
Artigo em Inglês | MEDLINE | ID: mdl-34835715

RESUMO

Recently, biomass-based materials have attracted increasing attention because of their advantages of low cost, environment-friendly and nonpollution. Herein, the feasibility of using corn stalk biomass fiber (CF) and Fe3O4 embedded chitosan (CS) as a novel biomass-based adsorbent (CFS) to remove chloramphenicol (CAPC) from aqueous solution. Structure of CFS was characterized by using X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FT-IR), Brunauer-Emmett-Teller (BET), scanning electron microscopy (SEM) and zeta potential techniques. The effects of solution pH, adsorption time and ion strength on the adsorption capacity were examined. Adsorption isotherms obtained from batch experiments were better fitted by Langmuir model compared with Freundlich model, Dubinin-Radushkevich model and Temkin model. Adsorption kinetic data matched well to the pseudo-second order kinetic model. CAPC adsorption was endothermic, spontaneous, and entropy-increasing nature on CFS. In addition, the CFS could be separated by an external magnetic field, recycled, and reused without any significant loss in the adsorption capacity of CAPC. Based on these excellent performances, there is potential that CFS can be considered as a proficient and economically suitable material for the CAPC removal from the water environment.

19.
Chemistry ; 27(71): 17960-17969, 2021 Dec 20.
Artigo em Inglês | MEDLINE | ID: mdl-34786776

RESUMO

The polymorphs of 2ClChMe-4 in Form I (ribbon-like crystal) and Form II (block-like crystal) were prepared, and they exhibited curling/flipping and expansion upon heating on account of single-crystal-to-single-crystal transformations. The irreversible phase transformations occurred separately at 53.2 °C and 57.8 °C for the crystals in Form I and Form II, during which the molecular conformation of 2ClChMe-4 changed and the molecules slipped along the (100) plane. Movement at the molecular level resulted in changes of cell parameters, which in turn led to macroscopic motions of the crystals upon heating. Additionally, the ribbon-like crystals of 2ClChMe-4 showed photo-induced bending driven by [2+2] cycloaddition. Accordingly, an actuator showing reversible bending behavior was fabricated triggered by light and heat successively. Like biomimetic self-actuators, such multi-stimuli mechanical responsive molecular crystals might have potential applications in soft robots, artificial muscles and microfluidic systems.


Assuntos
Chalcona , Chalconas , Biomimética , Reação de Cicloadição , Microfluídica
20.
Front Public Health ; 9: 764788, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34778191

RESUMO

A total of 214 sampling sites of a hazardous waste disposal center were surveyed in a two-stage pollution investigation, including soil boreholes and groundwater monitoring wells. Results showed that chemical oxygen demand (COD) (4.00-2930.00 mg/L), fluoride (0.07-9.08 mg/L), chromium (0.12-1.20 µg/L), nickel (0.15-459.00 µg/L), lead (0.10-10.20 µg/L), cadmium (Cd) (0.05-16.40 µg/L), and beryllium (0.06-3.48 µg/L) were detected in groundwater samples. For soils, Cd in soil (78.7 mg/kg) exceeded the risk screening value (65 mg/kg) for soil contamination of the second type of development land (GB36600-2018), and there remained the risk of leakage in the landfill detection investigation. Then, a health risk assessment was carried out. Based on the definitions of the groundwater exposure pathway (HJ 25.3-2019) and the pollution investigation of groundwater, the carcinogenic and non-carcinogenic risks of groundwater were generally considered to be negligible. The carcinogenic risk and non-carcinogenic risk of the concerned pollutant in soil for risk assessment (Cd) under the condition of reutilization exceeded the corresponding acceptable levels (1E-06 and 1). The (non-)carcinogenic risk of Cd mainly came from oral intake of soil and inhalation of soil particles under two conditions of reutilization and non-utilization, so on-site workers and surrounding residents should be properly protected from the mouth and nose to minimize the intake of pollutants from the soil and soil particles. The area of soil contaminated by Cd was about 630.58 m2, and the amount of pollution was about 1261.16 m3. The heavy metal pollution was only distributed in the depth range of 0-2 m, and the suggested risk control value of soil pollutants under the condition of reutilization for Cd was 56 mg/kg. Based on different pollution characteristics of soil, groundwater, and the landfill, targeted control measures were proposed.


Assuntos
Água Subterrânea , Metais Pesados , Monitoramento Ambiental , Resíduos Perigosos/efeitos adversos , Humanos , Metais Pesados/análise , Medição de Risco
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