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1.
Prep Biochem Biotechnol ; : 1-9, 2022 Jan 11.
Artigo em Inglês | MEDLINE | ID: mdl-35015605

RESUMO

Enzyme immobilization provides ideal operating conditions for enzymes stabilization and sustainable recycling. In this work, as a kind of clay material, montmorillonite (MTL) was chosen for immobilizing the ß-glucosidase extracted from Agrocybe aegirit. The immobilized ß-glucosidase via partly cross-linking enzyme aggregates (pCLEAs) formed by self-catalysis provided biocatalysts with satisfactory thermal and pH stability. Compared to the glutaraldehyde cross-linked, the immobilized ß-glucosidase (ß-G-pCLEAs@MTL) exhibited significantly higher immobilization efficiency (IE) and immobilization yield (IY), which were 80.6% and 76.9%, respectively. The ß-G-pCLEAs@MTL also showed better stability and preferable reusability. And the activity of the ß-G-pCLEAs@MTL remained 85.0% after 5 cycles and 74.7% after 10 cycles. Therefore, the method based on the pre- crosslinking to form pCLEAs and after-immobilization can effectively improve IY and IE. In addition, MTL seems to be a good alternative carrier to immobilize other enzymes for industrial application.

3.
Water Res ; 210: 118003, 2022 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-34982976

RESUMO

Eutrophication substantially influences the community structure of aquatic organisms and has become a major threat to biodiversity. However, whether eutrophication is linked to homogenization of microbial communities and the possible underlying mechanisms are poorly understood. Here, we studied bacterial and fungal communities from water and sediments of 40 shallow lakes in the Yangtze-Huaihe River basin, a representative area characterized by intensifying eutrophication in China, and further examined the beta diversity patterns and underlying mechanisms under eutrophication conditions. Our results indicate that eutrophication generally caused biotic homogenization of bacterial and fungal communities in both habitats showing decreased community variations for the sites with a higher trophic state index (TSI). In the two habitats, community dissimilarities were positively correlated with TSI changes for both taxonomic groups, while the local contribution to beta diversity (LCBD) remarkably declined with increasing TSI for the fungal community. These phenomena were consistent with the pivotal importance of the TSI in statistically accounting for beta diversity of bacterial and fungal communities in both habitats. In addition, we found that physicochemical factors such as water temperature and pH were also important for bacterial and fungal communities in water, while heavy metal elements were important for the communities in sediments. Interestingly, generalist species, rather than specialist species, were revealed to more dominantly affect the variations in beta diversity along the trophic gradient, which were quantified by Bray-Curtis dissimilarity and LCBD. Collectively, our findings reveal the importance of generalist species in contributing to the change of beta diversity of microbial communities along trophic gradients, which have profound implications for a comprehensive understanding of the effects of eutrophication on microbial community.

4.
Nanotechnology ; 33(15)2022 Jan 19.
Artigo em Inglês | MEDLINE | ID: mdl-34972094

RESUMO

The electronic structure of active sites is of importance for catalysts to achieve an optimized interaction with the intermediates. In this study, a unique organic-inorganic hybrid oxygen evolution reaction electrocatalyst composed of electrochemically inactive conducting polyaniline (PANI) and non-precious Fe-based oxide Fe3O4is presented. PANI molecules werein situloaded on Fe3O4nanoparticles through an efficient and simple process under mild conditions. The electronic structure of Fe3O4was modulated by creating a strong interaction with PANI molecules, leading to enhanced activity and stability of the catalyst to achieve 10 mA cm-2geometrical current density at overpotential of 265 mV in 1 M aqueous KOH solution. This work demonstrates that a highly efficient electrocatalyst can be achieved by molecular modification and provides a novel strategy for the optimization of the inactive non-precious catalysts.

6.
PLoS One ; 16(12): e0258790, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34855753

RESUMO

Bike-sharing is widely recognized as an eco-friendly mode of transportation and seen as one of the solutions to the problem of air pollution and congestion. With the emphasis on sustainability in transportation, bike-sharing systems is an emerging topic of urban transport and sustainable mobility related research. Existing studies mainly explored the factors affecting individuals' initial intentions to start using a shared bicycle, but few looked at the likelihood that a user would continue using one This study proposed a structural equation model with bike-sharing purchase decision involvement as independent variable, bike-sharing willingness to use as dependent variable, traveler participation and traveler perceived value as intermediary variables by introducing the concepts of purchase decision involvement, customer participation and perceived value in consumer psychology and behavior. A survey on bike-sharing users in Xi'an was conducted online and offline, and 622 effective responses were collected. The research model was tested by Amos 24.0 and the empirical results showed that All influencing factors including bike-sharing's purchase decision-making involvement, traveler participation and traveler's perceived value are found to be significantly and positively associated with usage intention; traveler perceived value play a chain-mediating role between bike-sharing purchase decision involvement and usage intention; bike-sharing purchase decision involvement have indirect effects on traveler perceived value through traveler participation. The results of this study enrich the current research's in the field of sharing economy, and it is certain guiding significant for how to obtain and maintain stable customers in bicycle-sharing industry.

7.
Artigo em Inglês | MEDLINE | ID: mdl-34898429

RESUMO

A dynamically weighted directed network (DWDN) is frequently encountered in various big data-related applications like a terminal interaction pattern analysis system (TIPAS) concerned in this study. It consists of large-scale dynamic interactions among numerous nodes. As the involved nodes increase drastically, it becomes impossible to observe their full interactions at each time slot, making a resultant DWDN High Dimensional and Incomplete (HDI). An HDI DWDN, in spite of its incompleteness, contains rich knowledge regarding involved nodes various behavior patterns. To extract such knowledge from an HDI DWDN, this paper proposes a novel Alternating direction method of multipliers (ADMM)-based Nonnegative Latent-factorization of Tensors (ANLT) model. It adopts three-fold ideas: a) building a data density-oriented augmented Lagrangian function for efficiently handling an HDI tensors incompleteness and nonnegativity; b) splitting the optimization task in each iteration into an elaborately designed subtask series where each one is solved based on the previously solved ones following the ADMM principle to achieve fast convergence; and c) theoretically proving that its convergence is guaranteed with its efficient learning scheme. Experimental results on six DWDNs from real applications demonstrate that the proposed ANLT outperforms state-of-the-art models significantly in both computational efficiency and prediction accuracy.

9.
Zhonghua Nan Ke Xue ; 27(2): 145-149, 2021 Feb.
Artigo em Chinês | MEDLINE | ID: mdl-34914331

RESUMO

Objective: To investigate the clinicopathological characteristics and prognosis of incidental prostate cancer (PCa). METHODS: We retrospectively analyzed the clinical data and pathological characteristics of 96 cases of incidental PCa in 580 patients undergoing radical cystectomy and followed them up for prognosis. RESULTS: The incidence rate of incidental PCa was 16.6% (96/580). The patients were 42-90 years old, with a median age of 73 years, 6 (6.2%) ≤60 and 90 (93.8%) over 60 years old. The average maximum diameter of the tumor was about 3.5 cm (range 1.0-9.0 cm). Histologically, 86 (89.6%) of the bladder cancer cases were high-grade invasive urothelial carcinoma (7 with squamous differentiation, 2 with sarcomatoid differentiation, 4 with glandular differentiation, and 1 with plasmacytoid/diffuse variant) and 7 were low-grade urothelial carcinoma, of which 1 case was poorly differentiated neuroendocrine carcinoma and 2 cases were bladder adenocarcinoma, including 1 case of signet ring cell carcinoma. All the PCa cases were classified as the histopathological type of classic acinar adenocarcinoma of the prostate, 67 (69.8%) with a Gleason score ≤ 6, and 29 (30.2%) with a Gleason score ≥ 7. Of the total number of incidental PCa cases, 32 (33.3%) were of clinical significance, and 59 (61.5%) of the patients were followed up for 1-95 (mean 28.7) months, during which 42 (71.2%) survived and 17 (28.8%) died, including 2 deaths due to non-cancer factors. No statistically significant difference was found in the median survival time between the 5 clinically significant and 10 non-clinically significant cases (P = 0.322). CONCLUSIONS: There is a high probability of incidental PCa among bladder cancer patients aged >60 years. Standardized sampling plays an important role in detection of the malignancy. There is only a small proportion of incidental PCa cases with clinical significance, and therefore it affects less the prognosis than bladder cancer.


Assuntos
Carcinoma de Células de Transição , Neoplasias da Próstata , Neoplasias da Bexiga Urinária , Adulto , Idoso , Idoso de 80 Anos ou mais , Humanos , Masculino , Pessoa de Meia-Idade , Neoplasias da Próstata/epidemiologia , Estudos Retrospectivos , Neoplasias da Bexiga Urinária/epidemiologia
10.
Front Oncol ; 11: 780938, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34966683

RESUMO

Background: CircPVT1 is demonstrated to promote cancer progression in esophageal squamous cell carcinoma (ESCC). However, the role and potential functional mechanisms of circPVT1 in regulating 5-fluorouracil (5-FU) chemosensitivity remain largely unknown. Methods: ESCC cells resistant to 5-FU were induced with continuous increasing concentrations of 5-FU step-wisely. A cell counting kit-8 assay was used to analyze the viability of ESCC cells. LDH release assay kit was used to evaluate the cytotoxicity. RT-qPCR was used to assess the expression level of non-coding RNAs and cDNAs. Luciferase was used to confirm the interaction between non-coding RNAs and targets. Western blotting was used to detect the expression of downstream signaling proteins. Flow cytometry and ferroptosis detection assay kit were utilized to measure the ferroptosis of ESCC cells. Results: CircPVT1 was significantly upregulated in ESCC cells resistant to 5-FU. Knockdown of circPVT1 enhanced the 5-FU chemosensitivity of ESCC cells resistant to 5-FU by increasing cytotoxicity and downregulating multidrug-resistant associated proteins, including P-gp and MRP1. Luciferase assay showed that circPVT1 acted as a sponge of miR-30a-5p, and Frizzled3 (FZD3) was a downstream target of miR-30a-5p. The enhanced 5-FU chemosensitivity by circPVT1 knockdown was reversed with miR-30a-5p inhibitor. Besides, the increased 5-FU chemosensitivity by miR-30a-5p mimics was reversed with FZD3 overexpression. Furthermore, knockdown of circPVT1 increased ferroptosis through downregulating p-ß-catenin, GPX4, and SLC7A11 while miR-30a-5p inhibition and FZD3 overexpression reversed the phenotype by upregulating p-ß-catenin, GPX4, and SLC7A11. Conclusions: These results suggested a key role for circPVT1 in ESCC 5-FU-chemosensitivity in regulating the Wnt/ß-catenin pathway and ferroptosis via miR-30a-5p/FZD3 axis, which might be a potential target in ESCC therapy.

11.
Pest Manag Sci ; 2021 Dec 12.
Artigo em Inglês | MEDLINE | ID: mdl-34897966

RESUMO

BACKGROUND: Velvet ash (Fraxinus velutina Torr.) is an important wood and ornamental tree species. Emerald ash borer (EAB), Agrilus planipennis Fairmaire, is a major wood borer of velvet ash. The aim of this study was to identify the secondary metabolites of velvet ash involved in regulating the dominant bacterium group of EAB. RESULTS: The amount of lignans in the phloem of infested trees had increased by 290.96% because of A. planipennis infection. The addition of lignans to the artificial diet significantly reduced the weight of the larvae and decreased the dominant bacterial group in the larval midgut, such as Pseudomonadaceae, Xanthomonadaceae, and Enterobacteriaceae. The FvPLR1, a key gene for lignan synthesis, was obtained based on the phloem transcriptome of velvet ash. The expression of FvPLR1 in the phloem of the infested tree was significantly higher than that in the noninfested tree. Meanwhile, FvPLR1 silenced by virus-induced gene silencing showed that its expression level and the lignan content were decreased by 69.91% and 31.65%, respectively. Interestingly, silencing FvPLR1 induced alterations in the dominant bacteria group in the larvae, with the reverse trend in the lignan-fed treatment. CONCLUSION: The evidence showed that FvPLR1 was a positive regulator. The increasing synthesis of lignans leads to resistance improvement in velvet ash, which will provide comprehensive insights into the tree defense system to wood borer infestation.

12.
Int J Med Inform ; 158: 104674, 2021 Dec 25.
Artigo em Inglês | MEDLINE | ID: mdl-34968960

RESUMO

BACKGROUND: Information asymmetry causes barriers for the patient's decision-making in the online health community. Patients can rely on the physician's self-disclosed information to alleviate it. However, the impact of physician's self-disclosed information on the patient's decision has rarely been discussed. OBJECTIVES: To investigate the impact of the physician's self-disclosed information on the patient's decision in the online health community and to examine the moderating effect of the physician's online reputation. METHODS: Drawing on the limited-capacity model of attention, we develop a theoretical model to estimate the impact of physician's self-disclosure information on patient's decision and the contingent roles of physician's online reputation in online healthcare community by econometric methods. We designed a web crawler based on R language program to collect more than 20,000 physicians' data from their homepage in Haodf-a leading online healthcare community platform in China. The attributes of the physician's information disclosure are measured by the following variables: emotion orientation, the quantity of information and the semantic topics diversity. RESULTS: The empirical analysis derives the following findings: (1) The emotion orientation in physician's self-disclosure information is positively associated with patient's decision; (2) Both excessive quantity of information and semantic topics diversity can raise barriers for patient's decision; (3) When the level of physician's online reputation is high, the negative effect of the quantity of information and semantic topics diversity are all strengthened while the positive effect of the emotion orientation is not strengthened. CONCLUSIONS: This study has a profound importance for a deep understanding of the impact of physician's self-disclosure information and contributes to the literature on information disclosure, the limited capacity model of attention, patient's decision. Also, this study provides implications for practice.

13.
Bioengineered ; 2021 Nov 05.
Artigo em Inglês | MEDLINE | ID: mdl-34738502

RESUMO

Breast cancer (BC) is the most frequently diagnosed cancer in women. Increasing evidence suggests that circular RNA (circRNA) exerts critical functions in BC progression. However, the roles of circRNA septin 9 (circSEPT9) in BC development and the underneath mechanism remain largely unclear so far. In this work, the RNA levels of circSEPT9, microRNA-149-5p (miR-149-5p) and solute carrier family 1 member 5 (SLC1A5) were detected by quantitative real-time polymerase chain reaction. Western blot was performed to check protein expression. Glutamine uptake, cell proliferation and cell apoptosis were investigated by glutamine uptake, cell counting kit-8, cell colony formation, 5-Ethynyl-29-deoxyuridine, flow cytometry analysis or DNA content quantitation assay. The interactions of miR-149-5p with circSEPT9 and SLC1A5 were identified by a dual-luciferase reporter assay. Mouse model assay was carried out to analyze the effect of circSEPT9 on tumor formation in vivo. Results showed that circSEPT9 and SLC1A5 expression were significantly upregulated, while miR-149-5p was downregulated in BC tissues and cells as compared with paracancerous normal breast tissues and human normal breast cells. Knockdown of circSEPT9 or SLC1A5 inhibited glutamine uptake and cell proliferation, but induced cell apoptosis in BC cells. SLC1A5 overexpression relieved circSEPT9 silencing-induced repression of BC cell malignancy. In mechanism, circSEPT9 regulated SLC1A5 expression by sponging miR-149-5p. In support, circSEPT9 knockdown led to delayed tumor tumorigenesis in vivo. In summary, these results indicates that circSEPT9 may act an oncogenic role in BC malignant progression by regulating miR-149-5p/SLC1A5 pathway, providing a novel mechanism responsible for BC development.

14.
Front Oncol ; 11: 761346, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34820329

RESUMO

Background: Increasing researches have been reported that epigenetic alterations play critical roles in ESCC development. However, the role of the histone demethylase KDM4D in ESCC tumorigenesis is poorly investigated. This study aims to discover the underlying mechanisms between KDM4D and ESCC progression. Methods: CCK-8 assays, clone formation assay and soft-agar assays were performed to assess cell proliferation. Transwell assay was utilized to assess cell migration efficiency, while sphere formation assay was used to evaluate the cell self-renewal ability. Bioinformatic analysis was conducted to identify prognostic factors and predict the potential E3 ubiquitin ligases. In vitro ubiquitination assay was conducted to confirm the regulations between SYVN1 and HMGB1. The mRNA levels or protein levels of genes were detected by real-time PCR and western blot analysis. In vivo tumor xenograft models were used to determine whether the HMGB1 inhibition affected the malignant features of ESCC cells. Result: Epigenome screening and low-throughput validations highlighted that KDM4D is a tumor suppressor in ESCC. KDM4D expressed lowly in tumors that predicts poor prognosis. KDM4D deficiency significantly enhanced tumor growth, migration and stemness. Mechanistically, KDM4D transcriptionally activates SYVN1 expressions via H3K9me3 demethylation at the promoter region, thereby triggering the ubiquitin-dependent degradation of HMGB1. Low KDM4D depended on accumulated HMGB1 to drive ESCC progression and aggressiveness. Targeting HMGB1 (Glycyrrhizin) could remarkably suppress ESCC tumor growth in vitro and in vivo, especially in KDM4D-deficient cells. Conclusions: We systematically identified KDM4D/SYVN1/HMGB1 axis in ESCC progression, proving novel biomarkers and potential therapeutic targets.

15.
J Hazard Mater ; : 127838, 2021 Nov 25.
Artigo em Inglês | MEDLINE | ID: mdl-34844805

RESUMO

Crystallization and immobilization of actinides to form actinide compounds are of significant importance for the extraction and reutilization of nuclear waste in the nuclear industry. In this paper, the state-of-art progress in the crystallization of actinides are summarized, as well as the main functionalization of the actinide compounds, i.e., as adsorbents for heavy metal ions and organic pollutant in waste management, as (photo)catalysts for organic degradation and conversion, including degradation of organic dyes and antibiotics, dehydrogenation of N-heterocycles, CO2 cycloaddition, selective alcohol oxidation and selective oxidation of sulfides. This review will give a comprehensive summary about the synthesis and application exploration of solid actinide crystalline salts and actinide-based metal organic frameworks in the past decades. Finally, the future perspectives and challenges are proposed in the end to give a promising direction for future investigation.

17.
Adv Mater ; : e2105778, 2021 Oct 22.
Artigo em Inglês | MEDLINE | ID: mdl-34676925

RESUMO

Interfacial thermal transport plays a prominent role in the thermal management of nanoscale objects and is of fundamental importance for basic research and nanodevices. At metal/insulator interfaces, a configuration commonly found in electronic devices, heat transport strongly depends upon the effective energy transfer from thermalized electrons in the metal to the phonons in the insulator. However, the mechanism of interfacial electron-phonon coupling and thermal transport at metal/insulator interfaces is not well understood. Here, the observation of a substantial enhancement of the interfacial thermal resistance and the important role of surface charges at the metal/ferroelectric interface in an Al/BiFeO3 membrane are reported. By applying uniaxial strain, the interfacial thermal resistance can be varied substantially (up to an order of magnitude), which is attributed to the renormalized interfacial electron-phonon coupling caused by the charge redistribution at the interface due to the polarization rotation. These results imply that surface charges at a metal/insulator interface can substantially enhance the interfacial electron-phonon-mediated thermal coupling, providing a new route to optimize the thermal transport performance in next-generation nanodevices, power electronics, and thermal logic devices.

18.
Appl Opt ; 60(24): 7346-7350, 2021 Aug 20.
Artigo em Inglês | MEDLINE | ID: mdl-34613022

RESUMO

Five-hundred-watt cylindrical vector beams (CVBs) at 1030 nm with the 3 dB linewidth being less than 0.25 nm have been generated from a narrow linewidth all-fiber linearly polarized laser by metasurface extracavity conversion. At maximum output power, the transmission efficiency and polarization extinction ratio of radially polarized cylindrical vector beams (RP-CVBs) are beyond 98% and 95%, respectively. The average power is approximately an order higher than previously reported high-power narrow-linewidth CVBs generated from fiber lasers. The temperature rise of the metasurface is less than 10°C at 500 W output power, which means that the system can be further power-scaled in the near future. The high-power, high-purity, and high-efficiency RP-CVBs generated by the metasurface demonstrate potential application of a metasurface in high-power CVBs lasers.

19.
Artigo em Inglês | MEDLINE | ID: mdl-34647207

RESUMO

As a key parameter, the particle size of residual coal contributes greatly to its oxidation characteristics, so it is a significant and far-reaching topic to explore the role of different particle sizes in coal spontaneous combustion disaster. In this work, temperature-programmed system (TPS) was applied to analyze the oxygen consumption rate and CO and C2H4 production rules of six groups of coal samples with different particle sizes in the process of oxidation heating. The critical temperature (CT) and xerochasy temperature (XT) of different coal samples were obtained, and the coal oxidation process was divided into three stages (S1, slow oxidation stage; S2, fast oxidation stage; and S3, combustion stage). Then, the apparent activation energy (E) and pre-exponential factor (A) in three stages were regressed combined with Arrhenius formula. The results show that the smaller the coal particle size is, the larger the specific surface area is, the stronger the adsorption capacity of coal molecules and oxygen molecules is, resulting in the larger oxygen consumption rate. The values of CT and XT with particle size of 0.125-0.18 mm and 2-4 mm are the smallest and largest. For coal samples with the same particle size, the maximum values of E and A occur in stage S3 and the minimum values appear in stage S1. This is mainly due to the higher temperature of stage S3, which allows the activation of functional groups with higher apparent activation energy, stronger collisions between activated molecules, and more intense oxidation reactions.

20.
Microb Ecol ; 2021 Oct 25.
Artigo em Inglês | MEDLINE | ID: mdl-34694450

RESUMO

Understanding the mechanisms underlying biodiversity patterns is a central issue in ecology, while how temperature and precipitation jointly control the elevational patterns of microbes is understudied. Here, we studied the effects of temperature, precipitation and their interactions on the alpha and beta diversity of soil archaea and bacteria in alpine grasslands along an elevational gradient of 4300-5200 m on the Tibetan Plateau. Alpha diversity was examined on the basis of species richness and evenness, and beta diversity was quantified with the recently developed metric of local contributions to beta diversity (LCBD). Typical alpine steppe and meadow ecosystems were distributed below and above 4850 m, respectively, which was consistent with the two main constraints of mean annual temperature (MAT) and mean annual precipitation (MAP). Species richness and evenness showed decreasing elevational patterns in archaea and nonsignificant or U-shaped patterns in bacteria. The LCBD of both groups exhibited significant U-shaped elevational patterns, with the lowest values occurring at 4800 m. For the three diversity metrics, soil pH was the primary explanatory variable in archaea, explaining over 20.1% of the observed variation, whereas vegetation richness, total nitrogen and the K/Al ratio presented the strongest effects on bacteria, with relative importance values of 16.1%, 12.5% and 11.6%, respectively. For the microbial community composition of both archaea and bacteria, the moisture index showed the dominant effect, explaining 17.6% of the observed variation, followed by MAT and MAP. Taken together, temperature and precipitation exerted considerable indirect effects on microbial richness and evenness through local environmental and energy supply-related variables, such as vegetation richness, whereas temperature exerted a larger direct influence on LCBD and the community composition. Our findings highlighted the profound influence of temperature and precipitation interactions on microbial beta diversity in alpine grasslands on the Tibetan Plateau.

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