Investigation on multiferroic properties of BiFeO3 ceramics

BiFeO₃ polycrystalline ceramics was prepared by solid-state reaction method and its structural, optical and magnetic properties were investigated. BiFeO₃ was synthesized in a wide range of temperature (825–880 °C) and a well crystalline phase was obtained at a sintering temperature of 870 °C. X-ray diffraction patterns of the samples were recorded and analyzed for the confirmation of crystal structure and the determination of the lattice parameters. The average grain size of the samples was found to be between 1–2 μm. The determined value of direct bandgap of BiFeO₃ ceramics was found to be 2.72 eV. The linear behavior of M-H curve at room temperature confirmed antiferromagetic properties of the BiFeO₃ (BFO). S shaped M-H curve was obtained at a temperature of 5 K. In the whole temperature measurement range (5–300 K) of M-T, no anomalies were observed due to high Curie temperature and Neel temperature of the BiFeO₃.     

锻造和热处理对Al-Si和Al-Pb轴承合金在油润滑条件下耐磨性的影响

研究了锻造态和热处理态不同成分铝基轴承合金在油润滑条件下的摩擦行为，以及材料的硬度、热处理制度和锻造对材料耐磨性的影响。所用材料是 Al-8.5Si-3.5Cu 和 Al-15Pb-3.7Cu-1.5Si-1.1Fe。在锻造过程中，应变范围为10%~20%。并对材料进行T6热处理。在销-盘式磨损试验机上对材料的摩擦性能进行测试。结果表明，锻造过程使材料的硬度得到增加；铸造应变在10%~20%的范围内对材料的摩擦磨损影响不明显。     

Selective Zinc(II)‐Ion Fluorescence Sensing by a Functionalized Mesoporous Material Covalently Grafted with a Fluorescent Chromophore and Consequent Biological Applications

A highly ordered 2D‐hexagonal mesoporous silica material is functionalized with 3‐aminopropyltriethoxysilane. This organically modified mesoporous material is grafted with a dialdehyde fluorescent chromophore, 4‐methyl‐2,6‐diformyl phenol. Powder X‐ray diffraction, transmission electron microscopy, N₂ sorption, Fourier transform infrared spectroscopy, and UV‐visible absorption and emission have been employed to characterize the material. This material shows excellent selective Zn²⁺ sensing, which is due to the fluorophore moiety present at its surface. Fluorescence measurements reveal that the emission intensity of the Zn²⁺‐bound mesoporous material increases significantly upon addition of various concentrations of Zn²⁺, while the introduction of other biologically relevant (Ca²⁺, Mg²⁺, Na⁺, and K⁺) and environmentally hazardous transition‐metal ions results in either unchanged or weakened intensity. The enhancement of fluorescence is attributed to the strong covalent binding of Zn²⁺, evident from the large binding constant value (0.87 × 10⁴ M ^?1). Thus, this functionalized mesoporous material grafted with the fluorescent chromophore could monitor or recognize Zn²⁺ from a mixture of ions that contains Zn²⁺ even in trace amounts and can be considered as a selective fluorescent probe. We have examined the application of this mesoporous zinc(II) sensor to cultured living cells (A375 human melanoma and human cervical cancer cell, HeLa) by fluorescence microscopy.     

Hybrid Androgen Receptor Inhibitors Outperform Enzalutamide and EPI-001 in in vitro Models of Prostate Cancer Drug Resistance

Androgen receptor targeted therapies for prostate cancer have serious limitations in advanced stages of the disease. While resistance to the FDA-approved enzalutamide is extensively documented, novel therapies based on epichlorohydrin scaffolds (EPI) are currently in clinical trials, but display suboptimal pharmacokinetics. Herein, we report the synthesis and biological characterisation of a novel class of compounds designed through covalently linking enzalutamide and EPI-001 through various triazole based linkers. The compounds display an 18 to 53 fold improvement in the cell killing potency towards C4-2b prostate cancer (PCa) cells compared to the gold standards of therapy, enzalutamide and EPI-001. The most promising compounds were proven to exhibit their toxicity exclusively through androgen receptor (AR) mediated pathways. This work sets the basis for the first class of hybrid AR inhibitors which successfully combine two drug moieties – EPI-001 and enzalutamide – into the same molecule.     

The Impact of Human Lipoaspirate and Adipose Tissue-Derived Stem Cells Contact Culture on Breast Cancer Cells: Implications in Breast Reconstruction

Background: Autologous fat transfer in the form of lipoaspirates for the reconstruction of the breast after breast cancer surgery is a commonly used procedure in plastic surgery. However, concerns regarding the oncologic risk of nutrient-rich fat tissue are widely debated. Previous studies have primarily focused on studying the interaction between adipose-derived stem cells (ASCs) and breast cancer cells. Methods: In this study, we performed a comprehensive analysis of the paracrine- and contact-based interactions between lipoaspirates, ASCs and breast cancer cell lines. An inverted flask culture method was used to study the contact-based interaction between lipoaspirates and breast cancer cells, while GFP-expressing breast cancer cell lines were generated to study the cell–cell contact interaction with ASCs. Three different human breast cancer cell lines, MCF-7, MDA-MB-231 and BT-474, were studied. We analyzed the impact of these interactions on the proliferation, cell cycle and epithelial-to-mesenchymal (EMT) transition of the breast cancer cells. Results: Our results revealed that both lipoaspirates and ASCs do not increase the proliferation rate of the breast cancer cells either through paracrine- or contact-dependent interactions. We observed that lipoaspirates selectively inhibit the proliferation of MCF-7 cells in contact co-culture, driven by the retinoblastoma (Rb) protein activity mediating cell cycle arrest. Additionally, ASCs inhibited MDA-MB-231 breast cancer cell proliferation in cell–cell contact-dependent interactions. Quantitative real-time PCR revealed no significant increase in the EMT-related genes in breast cancer cells upon co-culture with ASCs. Conclusion: In conclusion, this study provides evidence of the non-oncogenic character of lipoaspirates and supports the safety of clinical fat grafting in breast reconstruction after oncological surgical procedures. In vivo studies in appropriate animal models and long-term post-operative clinical data from patients are essential to reach the final safety recommendations.     

Trombe walls: A review of opportunities and challenges in research and development

Green building and sustainable architecture are new techniques for addressing the environmental and energy crises. Trombe walls are regarded as a sustainable architectural technology for heating and ventilation. This article reviews the application of Trombe walls in buildings. The reviews discuss the characteristics of Trombe walls, including Trombe-wall configurations, and Trombe-wall technology. The advantages and disadvantages of this sustainable architectural technology have been highlighted, and future research questions have been identified.     

Formalizing Service-Oriented Architectures

Service-oriented architecture (SOA) is defined as a paradigm for organizing and using distributed capabilities that might be under the control of different ownership domains. SOA is also known as a methodology for achieving application interoperability and reuse of IT assets in distributed computing environments characterized as transformable by the visibility, interaction, and effect dimensions.