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The new frontiers of learning in otorhinolaryngology: a reflection about challenges and advances
Stability, deactivation and regeneration study of a newly developed HZSM-5 and Ni-doped HZSM-5 zeolite catalysts for ethanol-to-hydrocarbon conversion
This work investigates the stability and regeneration of HZSM-5 and Ni/HZSM-5 catalysts in the ethanol-to-hydrocarbon conversion. The catalysts were characterised using different techniques and evaluated at 623 K and 7 h−1 for 96 h TOS with two regeneration cycles. HZSM-5 showed high stability with 100% ethanol conversion, while Ni/HZSM-5 catalysts maintained 100% stability for 48 h before dropping. Regenerated catalysts were comparable to the originals in terms of product distribution, stability, and performance. HZSM-5 preferred BTX, while Ni-doped catalysts favoured C5-C8, C9-C12, and C12+ synthesis. The regeneration process restored catalytic activity, especially for the Ni-doped catalysts, extending their life and reducing replacement costs
Effect of hydro-alcoholic extract of Nigella sativa on cisplatin-induced memory impairment and brain oxidative stress status in male rats
Objective: Studies have shown the complications of chemotherapy on learning and memory. Empirical evidence suggests that Nigella sativa (NS) has neuroprotective activities. Therefore, the aim of our study was to investigate the effects of NS on cisplatin-induced memory impairment.Materials and Methods: This study was conducted on 40 male rats grouped as: control (saline: 2 ml/kg, intraperitoneally (IP), once weekly/2 weeks), cisplatin (Cis, 2 mg/kg, IP, once weekly/2 weeks), NS (200 mg/kg, IP, once weekly/2 weeks), Cis +NS 200 (2 mg/kg Cis + 200 mg/kg NS, IP, once weekly/2 weeks), and Cis +NS 400 (2 mg/kg Cis + 400 mg/kg NS, IP, once weekly/2 weeks). Morris water maze (MWM) test was used to assess spatial learning and memory. In addition, superoxide dismutase (SOD) activity, and thiol and malondialdehyde (MDA) levels were evaluated in the brain.Results: Cis significantly enhanced the traveled distance and time spent in the target quadrant in the MWM test. Additionally, MDA levels increased in the Cis group, while thiol and SOD decreased in this group. As a result of treatment with NS, behavioral results were reversed in the groups receiving NS compared to the Cis group. Also, NS reduced MDA level but improved SOD and thiol levels in brain tissue samples.Conclusion: NS could improve memory impairment and oxidative stress in animals receiving Cis. Therefore, NS could be used as a potential food supplement to prevent neurotoxicity in patients undergoing chemotherapy
Applying targeted gene hybridization capture to viruses with a focus to SARS-CoV-2
Although next-generation sequencing technologies are advancing rapidly, many research topics often require selective sequencing of genomic regions of interest. In addition, sequencing low-titre viruses is challenging, especially for coronaviruses, which are the largest RNA viruses. Prior to sequencing, enrichment of viral particles can help to significantly increase target sequence information as well as avoid large sequencing efforts and, consequently, can increase sensitivity and reduce sequencing costs. Targeting nucleic acids using capture by hybridization is another efficient method that can be performed by applying complementary probes (DNA or RNA baits) to directly enrich genetic information of interest while removing background non-target material. In studies where sequence capture by hybridization has been applied to the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) virus, most authors agree that this technique is useful to easily access sequence targets in complex samples. Furthermore, this approach allows for complete or near-complete sequencing of the viral genome, even in samples with low viral load or poor nucleic acid integrity. In addition, this strategy is highly efficient at discovering new variants by facilitating downstream investigations, such as phylogenetics, epidemiology, and evolution. Commercial kits, as well as in-house protocols, have been developed for enrichment of viral sequences. However, these kits have multiple variations in procedure, with differences in performance. This review compiles and describes studies in which hybridization capture has been applied to SARS-CoV-2 variant genomes
Synergistic effects of EDTA and lysozyme on the properties of hydroxypropyl starch nano antibacterial films
Hydroxypropyl starch (HPS) nano antibacterial films incorporating Ethylene Diamine Tetraacetic Acid (EDTA) and lysozyme (LY) were fabricated via solvent casting method. The synergistic effects of EDTA and LY on the microstructure, component interactions, color, optical, mechanical, barrier and antibacterial properties of HPS nano antibacterial films were evaluated. The results indicated that EDTA and LY were well dispersed in the matrix of the HPS nano antibacterial films, the film-forming substrates have good compatibility, resulting in a dense multi-layer structure of the HPS nano antibacterial films. The addition of EDTA and LY increased the color parameters (L*, a*, b* and △E*) of the HPS nano antibacterial films. The synergistic effects of EDTA and LY significantly decreased the light transmission of the HPS nano antibacterial films. The presence of EDTA and LY increased the tensile strength (TS) and the elongation at break (EAB) of the HPS nano antibacterial films. The TS and EAB of E2.5L1 reached the highest values of 6.329 MPa and 50.24 %, respectively. The incorporation of EDTA and LY had positive effects on the improvement of water vapor permeability (WVP) and oxygen permeability (OP). The WVP and OP of E2.5L1 reached the highest values of 0.9350 × 10−12 g cm/cm2•s•Pa and 0.297 × 10 −2 g m/m2 •d, respectively. In addition, EDTA and LY had significant synergistic effects on the antibacterial activity against S. aureus (Gram-positive bacteria) and E. coli (Gram-negative bacteria). E2.5L1 exhibited the highest antibacterial activity and the inhibition zone diameters of S. aureus and E. coli were 3.69 mm and 4.28 mm, respectively. The HPS nano antibacterial films incorporating EDTA and LY are potential functional packaging materials
Powered haulage safety, challenges, analysis, and solutions in the mining industry; a comprehensive review
Satisfying safety issues plays a critical role in mining operations. Although the use of emerging technology became a new trend in preventing powered haulage hazards in the mining industry, these technologies themselves posed new hazards to the problem that are necessary to be identified, assessed, and managed together with common hazards. This study investigates the existing gaps in powered haulage safety to establish a comprehensive framework for conducting risk analysis procedures. To achieve this purpose, a literature search methodology is employed to recognize the most relevant resources and extract the essential information. The most critical hazards in powered haulage operations are identified and classified into main groups. Then, root causes and consequences are designated for these hazards, providing substantial elements for risk analysis, which serves as an effective hazard measurement. Afterward, an overview of popular risk analysis techniques applied in the mining industry is provided to establish a holistic risk analysis framework. Finally, available hazard management strategies are discussed as solutions for mitigating and preventing potential hazards. The study results demonstrated the importance of establishing comprehensive safety protocols, continuously upgrading the advanced technologies, regular training, and continuous risk assessment to mitigate and prevent fatal and non-fatal hazards in mining operations
Association of genetic polymorphisms with COVID-19 infection and outcomes: An updated meta-analysis based on 62 studies
Background: The relationship between genetic polymorphisms and coronavirus disease 2019 (COVID-19) remains to be inconsistent. This meta-analysis aimed to provide an updated evaluation of the role of genetic polymorphisms in the infection, severity and mortality of COVID-19 based on all available published studies. Methods: A systematic search was performed using six databases: PubMed, Embase, Web of Science, Cochrane Library, Chinese National Knowledge Infrastructure (CNKI) and Wanfang. Summary odds ratios (ORs) and corresponding 95 % confidence intervals (CIs) were used to calculate the genotypic comparison. All statistical analyses were conducted in Stata 12.0. Results: A total of 62 studies with 19600 cases and 28899 controls was included in this meta-analysis. For COVID-19 infection, ACE Ins/Del polymorphism might be related with significantly decreased risk of COVID-19 infection under dominant, homozygote and allelic models. Meanwhile, the IFITM3 rs12252 and TMPRSS2 rs12329760 polymorphisms were significantly associated with the increased risk of COVID-19 infection under one or more models. Regarding COVID-19 severity, ACE2 rs2074192, ACE2 rs2106809, IFITM3 rs12252 and VDR rs1544410 polymorphisms might be related with significantly increased risk of COVID-19 severity in one or more models. Moreover, the analysis of TMPRSS2 rs2070788 indicated that a variant A allele decreased the risk of COVID-19 severity in recessive model. For COVID-19 mortality, the variant C allele of IFITM3 rs12252 polymorphism might be related with significantly increased risk of COVID-19 mortality under all genetic models. Conclusions: This meta-analysis indicated that he infection, severity or mortality of COVID-19 were related to the above genetic polymorphisms, which might provide an important theoretical basis for understanding the clinical feature of COVID-19 disease
8q Gain Has No Additional Predictive Value in SF3B1MUT Uveal Melanoma but Is Predictive for a Worse Prognosis in Patients with BAP1MUT Uveal Melanoma
Purpose: Gain of chromosome 8q has been associated with poor prognosis in uveal melanoma (UM), and an increase in the absolute number of 8q-copies correlated with an even shorter survival. Splicing factor 3b subunit 1 (SF3B1)-mutated (SF3B1MUT) tumors display structural chromosomal anomalies and frequently show a partial gain of chromosome 8qter. A recent subset of SF3B1MUT UM with early-onset metastases has been identified, prompting the investigation of the relationship between survival, 8q gain, and SF3B1MUT UM. Design: Retrospective cohort study. Subjects: Patients diagnosed with UM who underwent enucleation or received a biopsy at the Erasmus MC Cancer Institute or the Rotterdam Eye Hospital, The Netherlands were included. Methods: Fifty-nine patients with SF3B1MUT tumors and 211 patients with BRCA1 associated protein 1 (BAP1)-mutated (BAP1MUT) tumors were included in this study. Copy number status and gene expression were assessed using either a single nucleotide polymorphism array, fluorescence in situ hybridization, and karyotyping, or a combination of these techniques. Disease-free survival was determined and a cut-off of 60 months was used to define early-onset metastatic disease. Main Outcome Measures: Disease-free survival. Results: Forty-eight patients with SF3B1MUT UM (81%) had chromosome 8q gain (3 copies, 78%; 4 copies, 22%). Kaplan–Meier analysis of SF3B1MUT UM did not indicate a difference in survival in patients with or without gain of 8q (P = 0.99). Furthermore, the number of 8q copies was not associated with survival when comparing early (P = 0.97) versus late (P = 0.23) metastases group. In contrast, the presence of 8q gain (86%) was correlated with a decreased survival in BAP1MUT UM (P = 0.013). Conclusions: We did not find a correlation between 8q gain and early-onset metastasis in SF3B1MUT tumors. Gain of 8q has no additional predictive value in SF3B1MUT tumors. In contrast, 8q gain is predictive of a worse prognosis in patients with BAP1MUT tumors. Thus, gain of chromosome 8q has additional predictive value for BAP1MUT tumors, but not for SF3B1MUT tumors. Financial Disclosure(s): The author(s) have no proprietary or commercial interest in any materials discussed in this article
Blockchain adoption in higher-education institutions in India: Identifying the main challenges
AbstractThis study aims to understand the challenges in adoption of blockchain technology in higher education institutions in India using the technological-organizational-environmental (TOE) framework. Blockchain brings transparency, efficiency in working systems, and leveraging trust. The benefits of blockchain are multifaceted and might be beneficial to educational institutions. However, the utilization of blockchain technology is presently in its nascent stage within the educational sector in India. This research employed a qualitative methodology involving semi-structured interviews with participants working in higher administration teams and IT teams in private universities in the Delhi-NCR region of India. The responses of the participants were analyzed using thematic analysis. The study found 10 main challenges that were categorized under the three dimensions of the TOE framework
Perception of wine with protection of origin using free association: case study Mexico
Social representations can be explored as an approach in food science to understand the type of information consumers have about a product. The objective of this study was to identify the social representations given to wine with protection of origin and Mexican wine, by consumers from four regions of Mexico, and to explore its valorization elements. The verbalization of the two wines was independently examined by the free association of words, through an Internet survey carried out on a sample of Mexican wine consumers (n = 615). Wine with origin protection was mainly represented by quality attributes in the Western, Central, and South regions of Mexico, and Mexican wine was conceptualized mainly with the identity of origin; in this case both stimuli formed a general tendency towards utilitarian meanings. The conceptualization of Mexicans regarding the two wines was distributed in both tangible and intangible categories; The representations granted in each region vary depending on the relationship that the culture of that area has with wine