Corrosion resistance of AZ91 magnesium alloy with pulse electrodeposited Ni-SiC nanocomposite coating

Magnesium and its alloys are the lightest of the structural metals, which makes them one of the most promising materials to minimize vehicle weight, but poor surface properties restrict the application of these alloys. In this paper, Ni-SiC nanocomposite coatings were applied on AZ91 magnesium alloy from Watts bath with SiC content 0 g.L-1 (pure Ni), 10 g.L-1 (Ni-10SiC) and 15 g.L-1 (Ni-15SiC) by application of pulse electrodeposition technique. The morphology and phase analysis were carried out by Scanning Electron Microscopy (SEM) and X-Ray Diffraction (XRD) analysis, respectively. Micro-hardness of specimens was measured and the results revealed a significant enhancement: from 74 Vickers for bare AZ91 magnesium alloy to 523 Vickers for coated specimen in the bath containing 15 g.L-1 SiC. The Corrosion behavior of the samples was studied by potentiodaynamic polarization, and the obtained data showed the superior corrosion resistance for the coated AZ91 magnesium alloy, i.e. the corrosion current density decreased from 2.69 mA.cm-2, for the uncoated sample, to 0.00046 mA.cm-2, for coated specimen in the bath containing 15 g.L-1 SiC and the corrosion potential increased from -2.069 V to -0.33 V for the same conditions

OCR Post-processing Using Large Language Models

Optical Character Recognition (OCR) technology transforms textual visuals into an electronically readable, non-graphical format of the text. This allows the editing and other text manipulation of the content by language technology software such as machine translation, text comprehension, query-answering systems, and search engines. While Optical Character Recognition (OCR) systems continually progress towards greater precision, several complications persist when dealing with low-resolution source images or those with multicolored backgrounds. Consequently, the text derived from OCR necessitates additional refinement to optimize accuracy, beneficial for various subsequent applications. It is recognized that the character accuracy of OCR-generated text may influence certain natural language processing tasks, including Information Retrieval, Named-Entity Recognition, and Sentiment Analysis. Post-processing techniques for Optical Character Recognition (OCR) consist of three fundamental stages of identifying incorrect words, producing a list of potential corrections, and selecting the accurate word from the list to replace the erroneous word. In this work, we are using large language models and word embeddings to detect recognition errors caused by the OCR software. In addition, we use the generative capabilities of these language models to suggest correction candidates to possibly fix the errors. Our work also includes the development of tools that can be used to further improve the OCR post-processing technologies

Remote Activation of Mechanotransduction via Integrin Alpha-5 via Aptamer-Conjugated Magnetic Nanoparticles Promotes Osteogenesis

Bone regeneration and repair are complex processes in the adult skeleton, and current research has focused on understanding and controlling these processes. Magnetic nanoparticle (MNP)-based platforms have shown potential in tissue engineering and regenerative medicine through the use of magnetic nanomaterials combined with remotely applied dynamic fields. Previous studies have demonstrated the ability of MNP-induced mechanoactivation to trigger downstream signaling and promote new bone formation. In this study, we aimed to compare the osteogenic induction achieved using the mechanoreceptor targets, Piezo1, Fzd1, Fzd2, and integrin alpha-5. We compared the binding efficacy of different types of agonists (antibodies vs. aptamers) to these receptors. Moreover, we optimized the aptamer concentration (2.5, 5, and 10 μg/mg) for the selected receptor to determine the optimum concentration for promoting bone formation. Our data demonstrated that the mechanoactivation of integrins (CD49e) significantly upregulated the RUNX2 and LEF1 genes compared to other selected receptors. Furthermore, comparing the mechanoactivation of cells using MNPs conjugated with CD49e antibodies and aptamers revealed that MNP–aptamers significantly enhanced the upregulation of LEF1 genes. This suggests that aptamer-mediated mechanoactivation is a promising alternative to antibody-mediated activation. Finally, our results showed that the concentration of the aptamer loaded onto the MNPs strongly influenced the mechanoactivation of the cells. These findings provide valuable insights into the use of MNP platforms for bone regeneration and highlight the potential of aptamers in promoting signaling pathways related to bone formation. The novelty of our study lies in elucidating the unique advantages of aptamers in mediating mechanoactivation, presenting a promising avenue for advancing bone regenerative strategies

Electrospun PGA/gelatin nanofibrous scaffolds and their potential application in vascular tissue engineering

Hadi Hajiali1, Shapour Shahgasempour1, M Reza Naimi-Jamal2, Habibullah Peirovi11Nanomedicine and Tissue Engineering Research Center, Shahid Beheshti University of Medical Sciences; 2Department of Chemistry, Iran University of Science and Technology, Tehran, IranBackground and methods: In this study, gelatin was blended with polyglycolic acid (PGA) at different ratios (0, 10, 30, and 50 wt%) and electrospun. The morphology and structure of the scaffolds were characterized by scanning electron microscopy, Fourier transform infrared spectroscopy, and differential scanning calorimetry. The mechanical properties were also measured by the tensile test. Furthermore, for biocompatibility assessment, human umbilical vein endothelial cells and human umbilical artery smooth muscle cells were cultured on these scaffolds, and cell attachment and viability were evaluated.Results: PGA with 10 wt% gelatin enhanced the endothelial cells whilst PGA with 30 wt% gelatin increased smooth muscle cell adhesion, penetration, and viability compared with the other scaffold blends. Additionally, with the increase in gelatin content, the mechanical properties of the scaffolds were improved due to interaction between PGA and gelatin, as revealed by Fourier transform infrared spectroscopy and differential scanning calorimetry.Conclusion: Incorporation of gelatin improves the biological and mechanical properties of PGA, making promising scaffolds for vascular tissue engineering.Keywords: polyglycolic acid, gelatin, nanofiber, vascular tissue engineering, biocompatible scaffold&nbsp

Prevalence survey and assessment of risk factors of musculoskeletal disorders among municipality workers in Isfahan city

زمینه و هدف: اختلالات اسکلتی- عضلانی (Musculoskeletal disorders= MSDs) از مهمترین عوامل ناتوانی شغلی در جهان هستند. این موضوع باعث شده که امروزه در دنیا تحقیقات زیادی در زمینه ارزیابی و کنترل این اختلالات انجام شود. مطالعه حاضر با هدف تعیین میزان شیوع و ارزیابی ریسک ابتلا به اختلالات اسکلتی- عضلانی در کارگران مشاغل فضای سبز در شهر اصفهان انجام شد. روش بررسی: در این مطالعه مقطعی، وظایف مختلف کارگر در فیلد فضای سبز مطالعه شدند. در هر عنوان وظیفه 12 کارگر و در مجموع 108 نفر انتخاب و به مطالعه راه یافتند. میزان شیوع درد ناشی از اختلالات اسکلتی- عضلانی با استفاده از پرسشنامه نوردیک و برای ارزیابی خطر ابتلا به اختلالات اسکلتی- عضلانی از روش QEC (Quick exposure check) استفاده شد. یافته ها: بر اساس نتایج حاصل از پرسشنامه نوردیک، 4/82 درصد از افراد این مطالعه در دستگاه اسکلتی- عضلانی دچار درد و ناراحتی بودند که بیشترین شیوع این اختلالات در ناحیه زانو (3/59 درصد) و کمر (8/52 درصد) گزارش شد. در جامعه مورد مطالعه بین سطح ریسک ارگونومیک کار و شیوع علایم اختلالات اسکلتی- عضلانی، ارتباط معنی داری وجود داشت (001/0>P). نتیجه گیری: از آنجایی که در 2/47 درصد از گروه های کاری مطالعه شده، سطح ریسک بالا و بسیار بالاست لازم است اقدامات اصلاحی و کنترلی هرچه زودتر شروع گردد. بر اساس ، عمده ترین مشکل ارگونومیکی در مشاغل فضای سبز پوسچر (Posture) نامطلوب، کارهای توأم با حرکات تکراری، خمش و پیچش کمر می باشد