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101.
102.
Elevated levels of Mucin-16 (MUC16) in conjunction with a high expression of truncated O-glycans is implicated in playing crucial roles in the malignancy of pancreatic ductal adenocarcinoma (PDAC). However, the mechanisms by which such aberrant glycoforms present on MUC16 itself promote an increased disease burden in PDAC are yet to be elucidated. This study demonstrates that the CRISPR/Cas9-mediated genetic deletion of MUC16 in PDAC cells decreases tumor cell migration. We found that MUC16 enhances tumor malignancy by activating the integrin-linked kinase and focal adhesion kinase (ILK/FAK)-signaling axis. These findings are especially noteworthy in truncated O-glycan (Tn and STn antigen)-expressing PDAC cells. Activation of these oncogenic-signaling pathways resulted in part from interactions between MUC16 and integrin complexes (α4β1), which showed a stronger association with aberrant glycoforms of MUC16. Using a monoclonal antibody to functionally hinder MUC16 significantly reduced the migratory cascades in our model. Together, these findings suggest that truncated O-glycan containing MUC16 exacerbates malignancy in PDAC by activating FAK signaling through specific interactions with α4 and β1 integrin complexes on cancer cell membranes. Targeting these aberrant glycoforms of MUC16 can aid in the development of a novel platform to study and treat metastatic pancreatic cancer.  相似文献   
103.
This work majorly aims to synthesize and also investigate the structural, optical, magnetic and optical features of ZrO2/ZnFe2O4 nanocomposite. Here, different ratios of novel hetero-junction ZrO2/ZnFe2O4 were synthesized by simple and fast solution combustion route. The X-ray diffraction results showed the formation of ZrO2 and ZnFe2O4 nanoparticles and ZrO2/ZnFe2O4 nanocomposites without any impurity. The formation of hetero-junction effectively inhibits the photo-generated charge carrier recombination. The degradation of Indigo Carmine dye by ZrO2/ZnFe2O4 photocatalyst was achieved through synergistic effects with 98% degradation and removal of 77% COD from the industrial dye waste water under Sunlight irradiation. Mixing of ferrites with zirconia greatly improves the photocatalytic activity that has been clearly proposed with the help of mechanism. ZZFO 12 NC exhibits better photocatalytic activity due to the combined facets of photo and Fenton activity. The exposure and enhancement of fingerprints in various surfaces are achieved by a modest, extremely sensitive and eco-friendly method. ZZFO12 NC offer great potential as an active photocatalyst for degradation of 54% of organic pollutant present in industrial waste water under natural Sunlight.  相似文献   
104.
Saha  Chinmoy  Bahera  Prasanta K.  Raut  Sagar Kumar  Singha  Nikhil K. 《SILICON》2021,13(4):1041-1049
Silicon - This investigation reports the preparation and properties of thermoplastic polyurethane/silica nanocomposite prepared via melt mixing process. In this case, nanosilica at different...  相似文献   
105.
In recent years, key study was designing nanomaterials (NMs) with tunable properties in order to obtain high functional materials. For this purpose, an attempt with great effort has been put forward to synthesize ZrO2:Eu:Li (1–11 mol%) NM with varying concentration of Li+ ion that can have a control over phase, size, morphology, crystallinity, band gap and surface chemistry. More importantly, addition of Li as codopant influences the phase and crystallinity change with the change in concentration. However important challenges faced by this work was to understand the phase change, crystallinity, structural change and photocatalytic activity which has to be still explored. The synthesized NMs possess mixed phase and cubic phase with change in concentration of codopant which may be attributed to presence of defect states, micro strain, distortion of lattice. The energy band gap was found to decrease for 7 mol% NM attributed to the change in the phase. Porous morphology with variation in pore length was observed. Enhanced luminescence intensity with intense orange red emissions consistent to 5D07Fj (j = 0 to 4) intra configurational f-f transitions was observed for ZrO2:Eu:Li+(1–11 mol%) nanophosphor excited at 394 nm. The visualization of latent fingerprints using ZrO2: Eu: Li+7mol% nanophosphor on several surfaces, the powder dusting technique was adopted. The enhanced fingerprint under UV light provides well resolved ridge patterns for the identification of individual latent finger prints using ZrO2:Eu:Li (7 mol%) with clear resolution. Lower charge transfer resistance with enhanced photocatalytic activity for decolourization of Rhodamine B with high pore length to allow multiple reflections under UV light irradiation for 7 mol% NM with reduced band gap and optimum luminescence intensity was observed. Hence, the synthesized ZrO2:Eu:Li (7 mol%) can be employed in forensic science towards latent fingerprint development, as a photocatalyst for environmental remediation and as luminescent material in display applications.  相似文献   
106.
This research deals with the facile combustion synthesis of manganese ferrite (MFO) nanoparticle with different cerium concentration and their potential application as an efficient photocatalyst and chemical sensor. The concentration of introduced cerium affects the size, structure, compositional, morphological, optical, photoluminescence and magnetic properties of the ferrite nanoparticle. The X-ray diffraction pattern affirmed the arrangement of cubic spinel structure with the formation of secondary phase CeO2 as the cerium concentration exceed 3 mol%. SEM micrographs revealed irregular morphology with more number of pores and voids. HRTEM along with SAED pattern revealed the crystalline cubic nature. The optical band gap deduced from UV–Vis-DRS spectra was observed to be in the range 2.3–2.8 eV. PL studies indicated a significant minimization in combination of electrons & holes in MnFe2O4 on addition of Ce dopant. VSM investigation demonstrated the soft magnetic nature of the prepared sample with moderate magnetization value. An excellent photocatalytic performance of Cerium doped MFO (3 mol%) towards MB and AR dye degradation was found to be 1.5 and 1.67 times more compared to host matrix under Sunlight irradiation that correlated to reduced band gap, Ce dopant and efficient separation of charge carriers. Cerium doped MFO (3 mol%) have high specific capacitance value of 471.7 and 1546.8 Fg-1 for NaNO3 and HCl electrolytes respectively, indicating the pseudo capacitance nature due to which it can be used as a supercapacitor. The synthesized nanoparticles can sense d-Glucose and Paracetamol even at a lower concentration varying from 1 to 10 mM. The synthesized Ce-doped MnFe2O4 nanomaterials have great potential to be used in the future production of promising active photocatalysts and sensitive chemical sensors for the identification and degradation of toxic industrial dyes for improved safety in the fields of environment and health care.  相似文献   
107.
Within the scope of this research, platelet‐shaped hexagonal Boron Nitride (h‐BN) with a size of 2 and 12 μm, and oval‐shaped Boehmite (BT) with a size of 2 μm were incorporated in a glass fiber‐reinforced epoxy novolac matrix cured with a diamine‐based hardener. The effects of the platelet size (BN 2 and 12 μm) and filler nature (BT vs. BN) were correlated with the final thermal and fire‐related properties. The incorporation of the fillers shows that not only the thermal conductivity (σ) was increased from approximately 0.2 up to 1.04 W/mK (through‐plane) but also the flame retardancy was improved by using a hybrid combination. The time to ignition (tig) was increased by 48 s and the FIGRA value was decreased from 6.5 to 3.3 indicating a much lower fire hazard for the material. scanning electron microscopic micrographs of the laminate cross sections show that the fillers are distributed and oriented randomly in the fiber‐reinforced matrix, and also highlight the fiber wetting. Furthermore, the results show that the resulting 3D filler network and infiltration of the intratow regions is strongly dependent on lateral filler size and filler combination. With increasing the filler aspect ratio, the effect on thermal properties and filtration is more evident. Moreover, the hybrid combination of BN and Boehmite fillers has a strong effect on the network formation during processing, resulting in enhanced thermal and mechanical properties. A synergy was observed when using BN 12 μm in combination with Boehmite 2 μm as the larger platelets tend to assemble themselves in the intertow region (resin‐rich region) and the smaller particles infiltrate into the intratow regions. This leads to a formation of a thermal pathway throughout the glass fabric barrier. Considering the cost factor, the through‐plane (z‐direction) heat dissipation and the flame retardancy can be tailored by optimizing the size, aspect ratio/geometry, and nature of the fillers. POLYM. ENG. SCI., 59:1840–1852, 2019. © 2019 The Authors. Polymer Engineering & Science published by Wiley Periodicals, Inc. on behalf of Society of Plastics Engineers.  相似文献   
108.
In this study, the room-temperature Charpy impact property of 3D-printed 15-5 stainless steel was investigated by a combined experimental and finite element modeling approach. The experimentally measured impact energy is 10.85 ± 1.20 J/cm2, which is comparable to the conventionally wrought and non-heat treated 15-5 stainless steel. In parallel to the impact test experiment, a finite element model using the Johnson–Cook material model with damage parameters was developed to simulate the impact test. The simulated impact energy is 10.46 J/cm2, which is in good agreement with the experimental data. The fracture surface from the experimentally tested specimen suggests that the 3D-printed specimens undergo predominately brittle fracture.  相似文献   
109.
This article describes the synthesis of molybdenum disulfide (MoS2) nanowires using chemical vapor deposition (CVD) method. The MoS2-nanowires converts into micro-flake structures with the help of argon (Ar) plasma for the better hydrogen evolution reaction (HER) activity. The MoS2-nanowires treated by post-Ar plasma at different time of intervals (20 seconds, 40 seconds, 60 seconds, and 3 minutes). The plasma treatment significantly tailored the structure of pristine MoS2-nanowires due to which additional active sites were produced at the surface of treated MoS2. A notable HER activity were achieved by plasma-treated MoS2. To boost the HER activity up to next level, visible light was used at the time of electrocatalysis which enhanced the electrocatalytic activity almost double, which is evident by the low overpotential (190 mV) at current density of 10 mAcm−2.  相似文献   
110.
Water splitting for H2 production by absorbing sunlight is broadly used as a common technique to counter existing energy crisis and environmental problems, caused by extreme use of fossil fuels. We report a versatile and facile method to fabricate ordered Silicon nanohorns (SiNHs) by employing prefabricated metal nano-gap template on Si. The close-packed monolayer is used to develop the nanohole template, which enables the generation of SiNHs via metal-assisted controlled chemical etching. By varying monolayer parameters and etching sequences, SiNHs with desired dimensions were obtained. Growth along the crystalline plane of the base substrate ?100?, with a consistent bent at the tip of the SiNH, has been observed. The resulting SiNHs exhibited enhanced photoelectrochemical properties, with short-circuit photocurrent density more than four times higher than that of the planer Si along with enhanced trapping of photogenerated carriers. A photocurrent density of ~4.8 mA/cm2 was observed at a potential of -1 V vs. RHE. Further, the electrochemical impedance study (EIS) was carried out to understand the photoelectrochemical activity and charge transfer kinetics of the SiNHs system. These nanostructures enhance light absorption and may be one of the low-cost alternatives for optical devices, sensors, and hydrogen evolution.  相似文献   
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