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Characterization and Performance of TiO2 Nanoparticles Prepared by Microwave in Different Mixtures of Water and Ethylene Glycol for the Food Dye E131 VF Degradation
Get PDFIn this research, TiO2 NP were prepared by MW-R and conventional SG methods, using TTIP as Ti precursor, in the presence of different mixtures of distilled H2O and ETG (0 < H2O/ETG < 100%), as a solvent. The prepared samples were characterized by XRD, Raman, FTIR, EDX/ SEM, N2 physisorption, DLS and UV/visible DRS techniques. XRD and Raman analyses showed that Ant phase dominated, with traces of Rt or Brk phases, in some samples. According to K-M curves, TiO2 calculated EG decreased with an increase in Rt phase percentage. PC performance of the prepared samples was tested on E131 VF. Kinetic evaluations showed that Rt percentage and surface area had a significant role in TiO2 NP PC performance. E131 VF degradation high RC were obtained in an AU by 0% ETG SG (0.130 (AU)) and 0% ETG MW-R (0.113 (AU)), due to the high surface area and Rt absence. The samples (x% ETG) synthesized by the MW-R method showed low pore volume and PC performance that might have been be due to a blockage of the pores and screening effect of some combustion products or residual ETG, which carried UV irradiation to the catalyst surface. © 2023, Sociedade Portuguesa de Electroquimica. All rights reserved
Fidaxomicin treatment for Clostridioides difficile infection in patients with inflammatory bowel disease
No full textBackground and Aim: Although fidaxomicin is an effective first-line treatment for Clostridioides difficile infection, it has not been well studied in patients with inflammatory bowel disease. We aimed to assess the effectiveness of fidaxomicin for the treatment of C. difficile infection in patients with inflammatory bowel disease. Methods: This was a multicenter retrospective study of adults with inflammatory bowel disease and C. difficile infection treated with fidaxomicin with at least 3 months of follow up. The primary outcomes were treatment response, defined as resolution of C. difficile infection-attributed diarrhea and/or negative C. difficile infection stool test, and time to C. difficile infection recurrence after fidaxomicin. Results: Thirty-three patients (median age 42 years; 60.6% female) were included. Most patients had ulcerative colitis (26, 78.8%), were receiving treatment with a biologic or small molecule medication (19, 57.6%), and had a prior episode of C. difficile infection (26, 78.8%, median 2 episodes, range 0–15). Fidaxomicin led to resolution of C. difficile infection in 20 (60.6%) patients, with 6/20 (30.0%) developing a recurrence at a median of 55 days. Most patients who failed to respond to fidaxomicin underwent fecal microbiota transplantation (10/13, 76.9%) with resolution. Conclusions: In this cohort of patients with inflammatory bowel disease and C. difficile infection, 60.6% responded to treatment with fidaxomicin. Of those who did not respond, fecal microbiota transplantation was an effective therapy. © 2023 Journal of Gastroenterology and Hepatology Foundation and John Wiley & Sons Australia, Ltd
Tamponade and massive pleural effusions secondary to peripherally inserted central catheter in neonates–A complication to be aware of
No full textBackground: Peripherally inserted central catheters (PICC) are frequently used in neonatal intensive care units (NICU) to assist premature and critically ill neonates. Massive pleural effusions, pericardial effusions, and cardiac tamponade secondary to PICC are extremely uncommon but have potentially fatal consequences. Objective: This study investigates the incidence of tamponade, large pleural, and pericardial effusions secondary to peripherally inserted central catheters in a neonatal intensive care unit at a tertiary care center over a 10-year period. It explores possible etiologies behind such complications and suggests preventative measures. Study design: Retrospective analysis of neonates who were admitted to the NICU at the AUBMC between January 2010 and January 2020, and who required insertion of PICC. Neonates who developed tamponade, large pleural, or pericardial effusions secondary to PICC insertion were investigated. Results: Four neonates developed significant life-threatening effusions. Urgent pericardiocentesis and chest tube placement were required in two and one patients, respectively. No fatalities were encountered. Conclusion: The abrupt onset of hemodynamic instability without an obvious cause in any neonate with PICC in situ should raise suspicion of pleural or pericardial effusions. Timely diagnosis through bedside ultrasound, and prompt aggressive intervention are critical. Copyright © 2023 Zareef, Anka, Hatab, El Rassi, Yunis, Bitar and Arabi
Determinants of advertising expenditures: Role of stock prices in an emerging market
Get PDFThis paper documents the relationship between advertising expenditures and stock prices. Using the data of non-financial firms from India, the paper shows that advertising expenditures of a firm are sensitive to its own stock prices and to stock prices of its peer firms during the period between 2000 and 2021. These findings remain qualitatively the same when we use different estimation procedures. The paper also shows that the relationship between advertising expenditures and stock prices depends on the level of product market competition. This relationship becomes more pronounced as product competition increases. © 2023 Akadémiai Kiadó, Budapest
Surgical Complications Requiring Reoperation in Open Versus Minimally Invasive Radical Nephrectomy: A Contemporary Analysis of the National Surgical Quality Improvement Program
Get PDFBackground: To explore reoperation rates for different radical nephrectomy (RN) approaches that are experiencing a shift from open radical nephrectomy (ORN) toward minimally invasive surgery (MIS), we aimed to compare reoperation rates along with their culprit etiologies between the different types of surgical approaches for RN. Methods: The national surgical quality improvement program dataset was used to select patients who underwent RN between the years 2012–2019. A 1:1 propensity score matched analysis was used. Reoperation rates and causes were then compared between open and MIS approach. Results: The propensity matched cohort included 15,294 patients. Reoperation rates due to large bowel injury (0.01 vs. 0.14%), vascular injury (0.07 vs. 0.22%), and other abdominal (0.5 vs. 0.77%) were more common in ORN as compared to MIS (MIS vs. ORN, respectively, p < 0.034). Reoperation due to hernia (0.14 vs. 0.03%) was more common in MIS as compared to ORN (p = 0.027). No difference was seen for small bowel injury and incision/wound debridement. General reoperation (1.61 vs. 2.22%) and mortality (0.57 vs. 1.47%) were also more common in ORN as compared to MIS (p < 0.008). Conclusion: Reoperation due to large bowel injury, vascular injury, and other abdominal was more likely to occur in ORN. Whereas reoperation due to hernia was more likely to occur in MIS. Surgical approach was an independent risk factor for immediate and early reoperation rates in RN patients. These results could be used to counsel patients pre-operatively on possible surgical approaches and complications. © 2022, The Author(s) under exclusive licence to Société Internationale de Chirurgie
Relation Between Bitcoin and Its Forks: An Empirical Investigation
No full textCryptocurrencies are generating increasing interest with concerns about various economic and financial implications. Investors in cryptocurrencies are affected by the massive jumps and crashes in the market and it is of interest to portfolio managers to answer the following question: Does investing in Bitcoin and its forks offer diversification for investors? This paper aims to answer this question by examining the relationship between the returns of Bitcoin and the returns of its forks and their associated volatilities. Our sample covers the period between 2010 and 2017 and includes Bitcoin and the portfolio of its forks. Our results, based on Dynamic GARCH model, indicate that there is a positive relation between the returns of Bitcoin and the returns of its forks. In addition, the results also show a positive relation between the volatility of Bitcoin and its forks. Finally, we found both the news effect and memory effect are significant. © 2023, EEA
Archaeobotany in Lebanon, Case Studies Proving the Value of Implementing Archaeobotanical Analysis in Excavations
Get PDFThis research aims to prove the importance of archaeobotanical analysis in archaeological contexts. In Lebanon, many archaeological excavations are conducted. Yet, the number of archaeobotanical analyses implemented for the sites are meager. Only a few sites are well represented, such as Tell Burak, Tell Fadous-Kfarabida, and Sidon. Unfortunately, that is not the case for all sites. This research presents three different case studies from different Lebanese sites: Qornet ed-Deir, Tell Kubba, and Tell Mirhan. These sites are located in different areas and were settled in different periods, which will prove the efficacy of archaeobotanical analysis in all locations and from all periods. The research process of archaeobotanical samples was conducted using the flotation method, then studied on a macrobotanical scale to identify the ancient seeds. Then, after the results are analyzed, the nature of the site and its available natural resources, and economic activity were investigated. Finally, a reflection on the potential of archaeobotany in Lebanon was discussed, as well as its possible enrichment of knowledge on Lebanese archaeological sites
The Radboud dysarthria assessment: validity and reliability of the Arabic version
Get PDFPurpose: To cross-culturally adapt and validate the Radboud Dysarthria Assessment (RDA) and the speech component of the Radboud Oral Motor inventory for Parkinson’s disease (ROMP-speech) into the Arabic language among Lebanese subjects with dysarthria. Materials and methods: This study included 50 participants with dysarthria. The Arabic versions of the RDA (A-RDA) and the ROMP-speech (A-ROMP-speech) were administered in addition to the Arabic Speech Intelligibility test, the Lebanese Voice Handicap Index–10 (VHI-10lb) and semantic verbal fluency tasks. The maximum performance tasks were analyzed using the Praat software. The A-RDA qualitative recording form and the A-ROMP-speech were assessed for construct validity and internal consistency. The convergent validity of the maximum performance tasks, the severity scale, and the A-ROMP-speech were evaluated. Results: Exploratory factor analysis of the qualitative recording form extracted 3 factors explaining 82.973% of the total variance, and it demonstrated high internal consistency (α = 0.912). The maximum performance tasks of the RDA correlated significantly with the corresponding Praat scores. The severity scale and the A-ROMP-speech correlated fairly to strongly with the Arabic Speech Intelligibility test (rs=-0.695 and −0.736, p < 0.001) and the VHI-10lb (r = 0.539 and 0.640, p < 0.001). Conclusion: The A-RDA and the A-ROMP-speech are valid and reliable dysarthria tools among Lebanese subjects. © 2023 Informa UK Limited, trading as Taylor & Francis Group
COMPARING THE ENVIRONMENTAL, ECONOMIC AND PERFORMANCE INDICES OF VARIOUS FIBER-REINFORCED CEMENT COMPOSITES
No full textConcrete is the most widely used building material in the world. The single largest limitation of concrete is its weak and brittle nature under tensile stress. To improve concrete behavior, reinforcement materials that are strong in tension are embedded into the concrete to avoid brittle failure and increase tensile capacity. Besides the traditional methods of embedding continuous aligned reinforcement in anticipated zones of tensile stress, random discrete fibers can be dispersed into the concrete during the mixing procedure to create a composite material called fiber reinforced concrete (FRC). Distinctive fiber filaments are used to improve the ductility and strain-hardening of cementitious composite mortars and grouts. Fibers vary commercially and environmentally so that polyvinyl alcohol (PVA) fibers are relatively expensive and might have higher environmental impact than Portland cement, polypropylene (PP), steel, basalt, and glass. Limited studies compared the effects of different fibers (PVA, PP, basalt, steel, and glass) on the hardened mechanical properties of normal-strength concrete mixtures, and on the behavior of structural members cast with such concrete mixtures. Moreover, many research studies addressed the issue of low tensile strength of concrete by adding fibers [1]. Based on that, this study aims to compare five different types of fiber reinforced cement composites, which are used in normal strength grade concrete based on their structural properties, environmental impacts, and cost. The five types of fibers are Basalt fiber (BF), Glass fibers (GF), Polypropylene fiber (PPF), Polyvinyl alcohol fiber (PVAF), and steel fiber (SF). The annual cement production in the world is over 4.4 billion tons. Moreover, the projected amounts by 2050 will reach over 5.5 billion tons [41]. This rapid growth of the construction sector leads to the consumption of natural resources and energy, which makes it essential to find more sustainable solutions for the future generations. So, in this research project, the environmental impacts and costs of different fibers and fiber-reinforced mixes that show good performance are studied. Lifecycle assessment from cradle- to- gate are performed for producing and receiving one kilogram of each kind of fibers using various environmental categories like Global Warming, Eutrophication, Toxicity, and Ozone Depletion, etc. Additionally, the life cycle assessment is done for 15 concrete mixes prepared at AUB laboratory and that reached acceptable mechanical properties. This research project helps in finding the most convenient composite from different aspects and highlights the phases in production and transportation which need improvement for a sustainable use of fibers in reinforced cement composites
Central vein sign and paramagnetic rim sign: From radiologically isolated syndrome to multiple sclerosis
Get PDFThe widespread use of magnetic resonance imaging (MRI) has led to an increase in incidental findings in the central nervous system. Radiologically isolated syndrome (RIS) is a condition where imaging reveals lesions suggestive of demyelinating disease without any clinical episodes consistent with multiple sclerosis (MS). The prognosis for RIS patients is uncertain, with some remaining asymptomatic while others progress to MS. Several risk factors for disease progression have been identified, including male sex, younger age at diagnosis, and spinal cord lesions. This article reviews two promising biomarkers, the central vein sign (CVS) and the paramagnetic rim sign (PRS), and their potential role in the diagnosis and prognosis of MS and RIS. Both CVS and PRS have been shown to be accurate diagnostic markers in MS, with high sensitivity and specificity, and have been useful in distinguishing MS from other disorders. Further research is needed to validate these findings and determine the clinical utility of these biomarkers in routine practice. © 2023 European Academy of Neurology