The major concerns of buckling-restrained braced frames (BRBFs) are the low post-yield stiffness and excessive residual displacement, which can delay the post-earthquake recovery procedure and ...enhance the repair cost. The current numerical work presents an innovative buckling-restrained brace (BRB) including a reduced-length hybrid core that is attached to a robust steel pipe. The core is laterally supported and consists of a shape memory alloy (SMA) rod inserted into a steel pipe. The paper represents a detailed description of the proposed device. The performance of the proposed BRB is numerically investigated at the component level using the ABAQUS finite element package. Subsequently, the system-level response of the proposed device is investigated by nonlinear static pushover and dynamic time history analyses in the OpenSEES environment. The results demonstrate that the proposed device shows a two-stage yielding mechanism, benefits the combined hysteretic responses of the SMA and the steel cores, and exhibits a stable and symmetric cyclic behavior with a nearly flag-shaped hysteresis. Furthermore, compared with conventional BRBs, the proposed device reduces the maximum inter-story and particularly the problematic residual drift responses of the BRBFs. Additionally, by an increase in the total area of the SMA core, though the maximum inter-story drift response is slightly increased due to the low elastic modulus of the SMA material, the residual drift response of the BRBFs is further decreased.
Many questions on the SARS-CoV-2 pathogenesis remain to answer. The SARS-CoV-2 genome encodes some accessory proteins that are essential for infection. Notably, accessory proteins of SARS-CoV-2 play ...significant roles in affecting immune escape and viral pathogenesis. Therefore SARS-CoV-2 accessory proteins could be considered putative drug targets. IFN-I and IFN-III responses are the primary mechanisms of innate antiviral immunity in infection clearance. Previous research has shown that SARS-CoV-2 suppresses IFN-β by infecting host cells via ORF3a, ORF3b, ORF6, ORF7a, ORF7b, ORF8, and ORF9b. Furthermore, ORF3a, ORF7a, and ORF7b have a role in blocking IFNα signaling, and ORF8 represses IFNβ signaling. The ORF3a, ORF7a, and ORF7b disrupt the STAT1/2 phosphorylation. ORF3a, ORF6, ORF7a, and ORF7b could prevent the ISRE promoter activity. The main SARS-CoV-2 accessory proteins involved in immune evasion are discussed here for comprehensive learning on viral entry, replication, and transmission in vaccines and antiviral development.
We investigated the effect of flow field and deformation rate on the nanotube alignment and on the properties of PC/multiwalled carbon nanotube nanocomposites. Samples of various MWCNT loadings were ...prepared by diluting a commercial masterbatch containing 15 wt% nanotubes using optimized melt mixing conditions. Different processing conditions were then used to systematically change the degree of nanotube alignment, from random orientation to highly aligned. Morphological studies and Raman spectroscopy analysis revealed that the nanotubes are preferentially aligned in the flow direction, particularly at large injection or compression rates. Rheological measurements corresponding to high shear rate conditions showed drastic changes in the viscoelastic behavior. The complex viscosity significantly decreased and percolation threshold notably rose. High degrees of nanotube alignment also resulted in a significant increase in the electrical percolation threshold. The mechanical properties of the nanocomposites for different nanotube loadings were also shown to depend on the processing conditions, and somehow improved when the material was processed at higher rates. Finally, we used a power-law type equation to correlate the percolation behavior and the nanotube alignment. The estimated percolation threshold and the power index, q, significantly increase with the degree of nanotube alignment as determined by Raman analysis.
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The world is faces a significant global health challenge in the form of viral infections, particularly the emergence of viral strains that are resistant to effective antiviral therapies. This ...underscores the urgent need for the development of effective and safe antiviral agents. Nanoscale materials are now being used as novel antiviral agents. Cerium nanoparticles have unique chemical and physical properties that make them particularly promising for viral infections. These particles reduce inflammation and the autoimmune response. Cerium nanoparticles, in addition to their antiviral properties, have many other advantages that are highly sought after for various aspects of biomedical applications. This review focuses on the various properties of cerium nanoparticles as a novel agent against viral infections.
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The new coronavirus outbreak emerged at the end of 2019 worldwide in a very short period of time. The number of victims of this virus until 2020/11/17 has been 1323143. The consequences of these ...viruses in humans are common cold or mild illness in the upper respiratory region. In more severe cases can causes severe interstitial pneumonia and acute respiratory distress syndrome (ARDS) and Middle East respiratory syndrome (MERS) and, severe acute respiratory syndrome (SARS). So far various drugs have been prescribed and used for the treatment. However, their efficiency and their side effects for treatment of pneumonia of COVID19 are unknown and should be more investigated. Low-dose radiation (LDR) (30 to 100 cGray(Gy)) has been used historically since the early 1930s with hopeful results for pneumonia treatment and was a common treatment solution for viral pneumonia until the 1940s. As some recent studies have raised the use of LDRT for COVID19 treatment, we sought to review previous evidence oftherapeutic role of LDRT in the inflammatory diseases as well as recent recommendations about consider LDRT as the treatment method for COVID19. Based on the available evidence and the background of studies, it seems that choosing a dose 0.3-0.5 Gy in severe cases of the disease, as well as using radiation for the whole body instead of the lungs, can optimize the immune system, and optimizing the immune system will help improve COVID-19.
This paper is concerned with several issues related to the rheological behavior of polycarbonate/multiwalled carbon nanotube nanocomposites. The composites were prepared by diluting a masterbatch of ...15 wt.% nanotubes using melt-mixing method, and the dispersion was analyzed by SEM, TEM, and AFM techniques. To understand the percolated structure, the nanocomposites were characterized via a set of rheological, electrical, and thermal conductivity measurements. The rheological measurements revealed that the structure and properties were temperature dependent; the percolation threshold was significantly lower at higher temperature suggesting stronger nanotube interactions. The nanotube networks were also sensitive to the steady shear deformation particularly at high temperature. Following preshearing, the elastic modulus decreased markedly suggesting that the nanotubes became more rigid. These results were analyzed using simple models for suspensions of rod-like particles. Finally, the rheological, electrical, and thermal conductivity percolation thresholds were compared. As expected, the rheological threshold was smaller than the thermal and electrical threshold.
Denture cleansers are extensively utilized to inhibit the colonization of various Candida species. Currently, additive technology in denture fabrication has become more prevalent. This study aims to ...assess the impact of disinfectants on the surface roughness and color stability of distinct denture bases. Disc-shaped samples (N=66) were exposed to three different disinfectants: 0.5% sodium hypochlorite, 1% hydrogen peroxide, and 2% chlorhexidine. The samples underwent evaluation via spectrophotometry and profilometry, respectively. Data analysis was conducted utilizing analysis of variance (ANOVA) (p < 0.05). Within the heat-cured group, sodium hypochlorite resulted in the most notable change in surface roughness (0.2 μm), while chlorhexidine exhibited the least impact (0.001 μm), showing a significant difference (p <0.008). The color change (ΔE) for 3D-printed samples immersed in all disinfectants was higher compared to heat-cured samples. Among the heat-cured samples, chlorhexidine induced the highest ΔE (2.76), while sodium hypochlorite resulted in the lowest (ΔE = 1.44), and this difference was statistically significant (p <0.008). Chlorhexidine caused the most significant color alteration among the solutions, while sodium hypochlorite induced the most considerable changes in surface roughness.
Gliomas, as Central Nervous System (CNS) tumors, are greatly common with 80% of malignancy. Treatment methods for gliomas, such as surgery, radiation therapy, and chemotherapy depend on the grade, ...size, location, and the patient's age.
This study aimed to quantify glioma based on the radiomics analysis and classify its grade into High-grade Glioma (HGG) or Low-grade Glioma (LGG) by various machine-learning methods using contrast-enhanced brain Computerized Tomography (CT) scans.
This retrospective study involved acquiring and segmenting data, selecting and extracting features, classifying, analyzing, and evaluating classifiers. The study included a total of 62 patients (31 with LGG and 31 with HGG). The tumors were segmented by an experienced CT-scan technologist with 3D slicer software. A total of 14 shape features, 18 histogram-based features, and 75 texture-based features were computed. The Area Under the Curve (AUC) and Receiver Operating Characteristic Curve (ROC) were used to evaluate and compare classification models.
A total of 13 out of 107 features were selected to differentiate between LGGs and HGGs and to perform various classifier algorithms with different cross-validations. The best classifier algorithm was linear-discriminant with 93.5% accuracy, 96.77% sensitivity, 90.3% specificity, and 0.98% AUC in the differentiation of LGGs and HGGs.
The proposed method can identify LGG and HGG with 93.5% accuracy, 96.77% sensitivity, 90.3% specificity, and 0.98% AUC, leading to the best treatment for glioma patients by using CT scans based on radiomics analysis.
Crimean-Congo hemorrhagic fever is a tick-borne disease with high fatality rate that is endemic in some parts of Asia, Africa and Europe. Rapid diagnostics of Crimean-Congo hemorrhagic fever (CCHF) ...is necessary for appropriate clinical management of this disease and also can be useful in preventing of secondary spread from human-to-human, though, common tests which are used to diagnose Crimean-Congo hemorrhagic fever have some limitations. Here we review 1) common diagnostic tests for CCHF, 2) limitations in laboratories methods of CCHF and 3) biosensor researches for detection of CCHF. It is necessary to design and develop an effective, rapid, and also low-cost tool such as biosensor to detect Crimean-Congo hemorrhagic fever. Based on the key role of rapid detection of CCHF in the control of infection, development of a biosensor as a rapid tool seems very major in the diagnosis of CCHF, though, there are limited studies on this field and more researches are needed in this issue.
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