Copper powder has broad applications in the powder metallurgy, heat exchanger, and electronic industries due to its intrinsically high electrical and thermal conductivities. However, the ease of ...formation of surface oxide or patina layer raises difficulty of storage and handling of copper powder, particularly in the case of Cu microparticles. Here, we developed a thermal chemical vapor deposition chemical vapor deposition (CVD) process for large-scale synthesis of graphene coatings on Cu microparticles, which importantly can remain monodisperse without aggregation after graphene growth at high temperature by using removal spacers. Compared to other protective coating methods, the intrinsic electrical and thermal properties of Cu powder would not be degraded by uniform growth of low defect few-layer graphene on each particle surface. As a result, when the anticorrosion performance test was carried out by immersing the samples in Cu etchant, the corrosion rate of graphene/Cu microparticles was significantly improved (ca three times slower) compared to that of pristine Cu powder, also showing a comparable anticorrosion ability to commercial CuZn30 alloy.
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IZUM, KILJ, NUK, PILJ, PNG, SAZU, UL, UM, UPUK
Copper-based materials are common industrial products which have been broadly applied to the fields of powder metallurgy, electrical contact, and heat exchangers, etc. However, the ease of surface ...oxidation limits the durability and effectiveness of copper-based components. Here, we have developed a powder metallurgy process to fabricate graphene/copper composites using copper powders which were first deposited with graphene layers by thermal chemical vapor deposition (CVD). The graphene/copper composites embedded with an interconnected graphene network was then able to be obtained by vacuum hot-pressing. After thermal oxidation (up to 220 °C) in humid air for several hours, we found that the degree of surface oxidation of our samples was much less than that of their pure Cu counterpart and our samples produced a much smaller increase of interfacial contact resistance when used as electrical contact materials. As a result, our graphene/copper composites showed a significant enhancement of oxidation resistance ability (≈5.6 times) compared to their pure Cu counterpart, thus offering potential applications as novel electrical contact materials.
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•Aromatic amphiphilic block copolymer named of amPEN has been synthesized.•AmPEN based micro-reactors are obtained via reverse emulsion self-assembly.•Silver nanoparticles (Ag NPs) ...are synthesized in the obtained micro-reactors.•Ag NPs are self-assembled into ~ 300 nm cube-like plasmonic superstructures (PSP).•Chlorpyrifos is detected via the optimized PSP SERS substrate.
Hierarchical anisotropic superparticles derived from the controlled assembly of individual plasmonic nanoparticles have been recognized as promising building blocks for surface-enhanced Raman spectroscopy (SERS) nanosensors. Thus, the protocols that precisely control the near-field coupling of individual plasmonic nanoparticles and the diffusion of highly diluted analytes to the plasmonic surface are of great interests. Herein, we have synthesized a series of aromatic amphiphilic block copolymers named as polyarylene ether nitrile (amPEN in short), containing a hydrophobic backbone of aromatic moieties with hydrophilic sulfonate/carboxyl and cyano groups in the side chain. Next, the surfactant stabilized water-in-oil (W/O) reverse emulsion is constructed to induce the confined self-assembly of amPEN, leading to the formation of functional micro-reactors for the in-situ synthesis and organization of silver nanoparticles, which finally contribute to the generation of sub-micrometer cube-like plasmonic superparticles (PSPs). Furthermore, the SERS nanosensors are created by drop-casting of synthesized PSPs on silicon substrate followed by depositing an additional thin layer of silver. Finally, the optimized SERS nanosensors with a Raman enhancement factor of 108 are able to detect chlorpyrifos pesticide down to 10-10 M thanks to the presence of abundant Raman hot-spots on the synthesized PSPs and the effective analyte enrichment derived from π-π interaction between pesticide molecules and aromatic backbone of amPEN.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
Glioblastoma (GBM) has a high degree of invasiveness, which is largely attributed to the invalidation of current therapy and the unclear tumor growth mechanism. Ras related GTP binding B (RRAGB) is a ...family member of the Ras-homologous GTPases. The effect of RRAGB on tumor growth has been recognized, but its influences on GBM progression are ill-defined. Here, in our research, a significantly decreased expression of RRAGB in GBM tissues by using TCGA databases and glioma samples is observed. According to Kaplan-Meier (KM) analysis, RRAGB low expression leads to a significant decrease of overall survival rate of patients, and is associated with the classification of WHO grade, histological type and age increase. Functional enrichment analysis reveals that the pathway of enrichment includes cell cycle arrest, extracellular matrix (ECM) processes and PI3K/AKT signal. Thereafter, our cell experiments confirm an obvious decrease of RRAGB in several GBM cell lines. It should be noted that RRAGB promotion strongly reduces the proliferation, migration and invasion of GBM cells and induces cell cycle arrest in G0/G1 phase. RRAGB up-regulation significantly decreases the expression of PI3K, phosphorylated AKT, mTOR and S6K in GBM cell lines. Surprisingly, we further find that RRAGB-restrained proliferative, migratory and invasive properties of GBM cells are markedly offset after promoting AKT activation, accompanied with restored phosphorylation of mTOR and S6K, elucidating that AKT signaling blockage is partially indispensable for RRAGB to play its anti-cancer role in GBM. Animal studies confirmed that RRAGB over-expression obviously inhibits the tumor growth both in the xenograft and orthotopic mouse glioma models, along with improved overall survival rates. In short, we provide evidence that RRAGB is a potential therapeutic target and prognostic marker for GBM treatment.
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•RRAGB down-regulation is involved in GBM progression.•RRAGB exhibits a correlation with PI3K/AKT, cell cycle arrest regulation.•RRAGB inhibits the cell proliferation, migration and invasion of GBM cell lines.•PI3K/AKT blockage is required for RRAGB to restrain GBM progression in vitro.•RRAGB suppresses GBM growth in vivo.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
Objective. To explore the effect of CT/MRI image fusion on cerebrovascular protection, postoperative complications and limb function recovery in patients with anterior and middle skull base tumors. ...Methods. During January 2019 to December 2021, a retrospective study was conducted on 50 patients who underwent anterior and middle skull base tumor resection in the same surgeon group in our hospital. According to the different surgical approaches, the patients were assigned to the fusion group (n = 29) and the routine group (n = 21). The routine group was operated with traditional operation, and the fusion group was operated with CT/MRI image fusion technique. The operation time, wound volume, resection rate and Karnofsky performance status (KPS), blood transfusion (vascular protection), tumor resection rate, and postoperative complications were compared. Results. The time of operation in the fusion group was shorter compared to the routine group, and the volume of the wound cavity in the fusion group was smaller compared to the routine group, and the difference was statistically significant (P<0.05). Following treatment, the KPS score of the fusion group was remarkably higher compared to the routine group, and the difference was statistically significant (P<0.05). The intraoperative blood transfusion rate in the fusion group was 17.24%, and the intraoperative blood transfusion rate in the routine group was 47.62%, and the difference was statistically significant (P<0.05). The resection rate in the fusion group (89.66%) was remarkably higher compared to the routine group (61.90%, P<0.05). The incidence of postoperative complications in the fusion group (6.90%) was remarkably lower compared to the control group (33.33%, P<0.05). Conclusion. The application of CT/MRI image-fusion technology can effectively enhance the clinical symptoms of patients with tumors in the anterior and middle region of the skull base, which can promote the prognosis, shorten the operation time, reduce unnecessary cerebral neurovascular injuries, and retain more brain functions.
Genome-wide association studies (GWAS) have identified numerous genetic variants that are associated with lung cancer risk, but the biological mechanisms underlying these associations remain largely ...unknown. Here we investigated the functional relevance of a genetic region in 6q22.2 which was identified to be associated with lung cancer risk in our previous GWAS. We performed linkage disequilibrium (LD) analysis and bioinformatic prediction to screen functional SNPs linked to a tagSNP in 6q22.2 loci, followed by two case-control studies and a meta-analysis with 4403 cases and 5336 controls to identify if these functional SNPs were associated with lung cancer risk. A novel SNP rs17079281 in the DCBLD1 promoter was identified to be associated with lung cancer risk in Chinese populations. Compared with those with C allele, patients with T allele had lower risk of adenocarcinoma (adjusted OR = 0.86; 95% CI: 0.80-0.92), but not squamous cell carcinoma (adjusted OR = 0.99; 95% CI: 0.91-1.10), and patients with the C/T or T/T genotype had lower levels of DCBLD1 expression than those with C/C genotype in lung adenocarcinoma tissues. We performed functional assays to characterize its biological relevance. The results showed that the T allele of rs17079281 had higher binding affinity to transcription factor YY1 than the C allele, which suppressed DCBLD1 expression. DCBLD1 behaved like an oncogene, promoting tumor growth by influencing cell cycle progression. These findings suggest that the functional variant rs17079281C>T decreased lung adenocarcinoma risk by creating an YY1-binding site to suppress DCBLD1 expression, which may serve as a biomarker for assessing lung cancer susceptibility.
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EMUNI, FIS, FZAB, GEOZS, GIS, IJS, IMTLJ, KILJ, KISLJ, MFDPS, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, SBMB, SBNM, UKNU, UL, UM, UPUK, VKSCE, ZAGLJ
Membrane fouling, especially inorganic fouling due to salt crystal formation and deposition on the membrane surface, is still a major technical issue in membrane distillation (MD) applications. In ...this study, microbubble aeration (MBA) was included in a laboratory-scale vacuum membrane distillation (VMD) rig and its effect on a desalination process was examined. Without MBA, serious membrane scaling occurred during desalination of simulated high-salinity sea water (100 g.L−1 salt concentration), which resulted in a dramatic reduction of permeate flux to essentially zero after 120 min. Scanning electron microscopy showed that a layer of large cuboid salt crystals uniformly covered the membrane surface. However, membrane scaling was mitigated with the introduction of MBA, resulting in the improved VMD desalination performance, which was positively correlated with pump pressure in the microbubble (MB) generator. Results showed that the effective processing time of the VMD desalination processing cycle was respectively prolonged to 150, 180, and more than 300 and 360 min (cf. 120 min without MBA) when the pump pressure was respectively at 0.1, 0.2, 0.3 and 0.4 MPa, leading to the increase of cumulative water production. Further studies found that larger numbers of MBs of smaller size were produced at higher pump pressure, which are more beneficial for increasing water vapor production and alleviating salt precipitation. The difference in zeta potential between the MBs in distilled water (about −30 mV) and that in SW100 solution (about -2 mV) demonstrated that MBA not only effectively mitigated the negative effect of concentration polarization by enhancing the surface shear rate at the membrane surface, but also reduced salt precipitation probably due to the MBs attracting counterions to the gas-water interface. Finally, energy consumption analysis of the modified VMD desalination process revealed that MBA, while itself only adding about 3% to the total energy consumption at varied pump pressures, was able to improve the specific energy consumption, especially at higher pump pressures. Together, these results demonstrate that MBA is an effective way of improving the performance of VMD desalination of water.
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•Microbubble aeration (MBA) effectively improved VMD desalination performance.•Membrane scaling was alleviated with the introduction of MBA.•MBA markedly improved the specific energy consumption.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
Pneumonia-like primary pulmonary lymphoma (PPL) was commonly misdiagnosed as infectious pneumonia, leading to delayed treatment. The purpose of this study was to establish a computed tomography ...(CT)-based radiomics model to differentiate pneumonia-like PPL from infectious pneumonia.
In this retrospective study, 79 patients with pneumonia-like PPL and 176 patients with infectious pneumonia from 12 medical centers were enrolled. Patients from center 1 to center 7 were assigned to the training or validation cohort, and the remaining patients from other centers were used as the external test cohort. Radiomics features were extracted from CT images. A three-step procedure was applied for radiomics feature selection and radiomics signature building, including the inter- and intra-class correlation coefficients (ICCs), a one-way analysis of variance (ANOVA), and least absolute shrinkage and selection operator (LASSO). Univariate and multivariate analyses were used to identify the significant clinicoradiological variables and construct a clinical factor model. Two radiologists reviewed the CT images for the external test set. Performance of the radiomics model, clinical factor model, and each radiologist were assessed by receiver operating characteristic, and area under the curve (AUC) was compared.
A total of 144 patients (44 with pneumonia-like PPL and 100 infectious pneumonia) were in the training cohort, 38 patients (12 with pneumonia-like PPL and 26 infectious pneumonia) were in the validation cohort, and 73 patients (23 with pneumonia-like PPL and 50 infectious pneumonia) were in the external test cohort. Twenty-three radiomics features were selected to build the radiomics model, which yielded AUCs of 0.95 (95% confidence interval CI: 0.94-0.99), 0.93 (95% CI: 0.85-0.98), and 0.94 (95% CI: 0.87-0.99) in the training, validation, and external test cohort, respectively. The AUCs for the two readers and clinical factor model were 0.74 (95% CI: 0.63-0.83), 0.72 (95% CI: 0.62-0.82), and 0.73 (95% CI: 0.62-0.84) in the external test cohort, respectively. The radiomics model outperformed both the readers' interpretation and clinical factor model ( P <0.05).
The CT-based radiomics model may provide an effective and non-invasive tool to differentiate pneumonia-like PPL from infectious pneumonia, which might provide assistance for clinicians in tailoring precise therapy.
Abstract
In the present study, ice production in a natural river reach has been studied by means of the thermodynamic theory regarding the heat flux between ice, air, riverbed, and water. The heat ...transfer coefficient and equivalent total heat flux were determined for different periods during winter. The characteristics of variation and distribution of ice production in the Inner Mongolia Reach of the Yellow River (IMRYR) were studied in combination with the change of heat flux. A model for describing the temporal–spatial variation of ice production for the IMRYR has been developed. The ice production process of the IMRYR from 2017 to 2021 was simulated using the proposed model, and the simulation results were in good agreement with those of the measurements. Results of the analysis showed that when the total ice production in the Bayangaole gauging station reaches 3.18 × 107 m3, a freeze-up process in this river reach is likely to occur. The influence degree of each variable on the ice production was in the following descending order: water surface area, air temperature, radiation, and flow. Particularly, a change of 20% of the water surface area will lead to a 11.48% change in the final calculated result of ice production.
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