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Thermoplastic Polyurethane‐Oleic Acid (<scp>TPU</scp>‐<scp>OLE</scp>) Membranes for Guided Bone Regeneration
No full textABSTRACTGuided bone regeneration (GBR) is a regenerative surgical procedure in dentistry and orthopedics. The aim of this study is to fabricate a novel nano‐textured, hydrophilic thermoplastic polyurethane (TPU)‐based barrier membrane containing unsaturated fatty acid, oleic acid (OLE) to assist GBR. First, TPU copolymer containing OLE in different ratios was synthesized, and GBR membranes were fabricated by the solvent casting method, and then, the surface properties were improved by alkali treatment. Thus, a TPU‐OLE structure was obtained with improved surface wettability, the ability to prevent bacterial adhesion, and the capability to promote cell adhesion. The contact angle reduced from 73.3° ± 1° to 30.7° ± 0.3° at TPU‐OLE3, while at TPU it decreased from 121.2° ± 2.5° to 63.6° ± 0.8° after treatment with 3 M sodium hydroxide (NaOH) solution. Furthermore, plate counting assays showed that TPU‐OLE membranes displayed excellent bacterial inhibition (against Escherichia coli and Staphylococcus aureus); the control group showed 6 × 107 CFU/mL of E. coli bacterial colonies, while on the plates interacting with TPU‐OLE1, TPU‐OLE2, and TPU‐OLE3 membranes, colonies of 12 × 105, 12 × 105, and 24 × 105 CFU/mL were observed, respectively. The bacterial count on TPU‐OLE1, TPU‐OLE2, and TPU‐OLE3 membranes decreased by 109, 164, and 12 × 105 CFU/mL at 24 h, while the control group and TPU membranes showed 1300 × 105 and 600 × 105 CFU/mL, respectively. The obtained results indicated that either alkali treatment or OLE‐modified TPU produced a more hydrophilic and promotive surface for cell attachment. Therefore, we anticipate that alkali‐treated TPU‐OLE membranes have a great potential in GBR in future applications.</jats:p
The Effect of Internal and External MQL Methods Used for Environmentally Friendly Manufacturing on Machining Performance in Drilling AA2024 Alloys: A Comparison for ANN And Taguchi Analyzes
No full textIn recent years, the interest in sustainable manufacturing has created an increasing demand for the economical and environmentally friendly Minimum Quantity Lubrication (MQL) method. However, there are not enough studies comparing internal and external MQL applications in drilling operations. The aim of this study is to investigate the effects of internal and external MQL application on drilling performance. Using Taguchi L9 experimental design, AA2024 aluminum alloy was drilled under three different cooling conditions (internal MQL, external MQL, dry), three different cutting speeds (100, 125, 150 m/min) and three different feeds (0.10, 0.15, 0.20 mm/rev). Surface roughness (Ra) was determined as the performance criterion, 30 repetitions were made in each experiment and the average Ra values were calculated for each condition. At the end of the experiments, the lowest Ra value (0.5 µm) was obtained in the internal MQL condition where the lowest cutting speed (100 m/min) and feed (0.1 mm/rev) parameters were used. In the external MQL condition, Ra results close to dry cutting were observed. The ANOVA analysis revealed that the control factor with the greatest effect on Ra values was the cooling condition. In addition, tool wear after the 30th hole was examined with SEM images and minimum deformation was observed in the internal MQL. ANN and Taguchi analyses were applied to the Ra data measured in the experiments. It was observed that the measured Ra data were in agreement with the data estimated using the Taguchi approach by 97% and with the data estimated using the ANN approach by 99%.</jats:p
Scientometric Analysis of Energy Efficiency Indicators in Maritime Transportation: A Systematic State-of-the-Art Review and Implications
No full textThis study investigates energy efficiency indicators including the Energy Efficiency Design Index (EEDI), Energy Efficiency Operational Index (EEOI), Ship Energy Efficiency Management Plan (SEEMP), Energy Efficiency Existing Ship Index (EEXI), and Carbon Intensity Indicator (CII) by providing a comprehensive scientometric analysis. The specified indices are scrutinized using papers from WoS and Scopus databases by applying the Preferred Reporting Items for Systematic Reviews and Meta Analyses (PRISMA) method to select the most appropriate papers in the related literature. Keyword and citation analysis of papers were performed using the VOSviewer software program to reveal the current research trends. The analysis addresses several critical aspects. Firstly, it focuses on identifying which indicators are employed more frequently in the literature, and secondly, it classifies the research according to whether a calculation was made, and the yearly distribution was determined. The results pinpoint that the EEDI and EEOI were examined in 42.55% and 22.49% of the reviewed studies, respectively. Furthermore, it is evident that the EEXI and CII percentages have increased drastically over the past three years, with the figures standing at 20.01% and 18.59%, respectively. Consequently, in alignment with the findings, the theoretical and managerial implications are highlighted for the private sector, academia, and maritime stakeholders.</jats:p
P-1226. Dose Optimization of β-lactams against Carbapenem-Resistant Pseudomonas from Turkiye Defined as Susceptible to Ceftazidime, Cefepime or Piperacillin/Tazobactam
No full textAbstract Background Due to the increasing prevalence of carbapenem-Resistant Pseudomonas aeruginosa (CRPA), effective agents are needed to treat these serious infections. Although CRPA may test susceptible to other β-lactams such as ceftazidime (CAZ), cefepime (FEP), and piperacillin/tazobactam (TZP), reduced potency has been observed amongst CRPA. In this study, we used PKPD analysis to assess the adequacy of the EUCAST Susceptible (S) or Susceptible Increased Exposure (SIE)/(I) doses for CAZ, FEP, and TZP against CRPA clinical isolates.Figure 1.Probability of target attainment (PTA) of various ceftazidime different dosing regimens and the MIC distribution of carbapenem-resistant Pseudomonas aeruginosa (CR-PA). Methods CRPA isolates were collected from patients at three Turkish hospitals between January 2017-December 2021. CAZ, FEP, and TZP MICs were determined using broth microdilution according to CLSI methodology. Monte Carlo simulations were performed to determine the probability of target attainment (PTA) for a free time above the MIC (fT &gt;MIC) targets for various doses of each agent against isolates defined as susceptible. fT &gt;MIC targets were 70% for CAZ or FEP and 50% for TZP. Cumulative fraction of response (CFR) was calculated by integrating PTA with the MIC distribution of the isolates. Optimal PTA and CFR were defined as 90% target achievement.Figure 2.Probability of target attainment (PTA) of various cefepime different dosing regimens and the MIC distribution of carbapenem-resistant Pseudomonas aeruginosa (CR-PA). Results In the setting of CR-PA, the percentages of isolates susceptible to CAZ, FEP, and TZP were 49,8%, 47%, and 31,8%, respectively. Reduced potency was noted with 54,1% of CAZ-S isolates had MICs of 4 or 8 mg/L. Of the FEP and TZP-S isolates, MICs at the breakpoint (8 and 16 mg/L, respectively) were the mode with 45,2 and 53,9% of isolates for each, respectively. At an MIC of 8 mg/L for CAZ, the EUCAST standard dose was found to be insufficient with a CFR of 85%. 3-hour infusions of EUCAST SIE doses were required for 90% PTA at MIC of 8 mg/L and an optimized CFR of 100% (Figure 1). For FEP, the SIE dose of 2 g q8h 0.5 h infusion of was effective (CFR 96%), utilization of an extended 3h infusion further optimized the PTA at 8 mg/L (CFR 99%) (Figure 2). For TZP, the standard dose of 4.5 q6h administered as a 0.5h infusion was inadequate (CFR 86%). A standard TZP dose with an extended infusion (4.5 g IV q8h over 4 h) and the SIE dose 4.5 g IV q6h 3 h inf resulted in CFRs &gt;95% (Figure 3).Figure 3.Probability of target attainment (PTA) of various piperacillin/tazobactam different dosing regimens and the MIC distribution of carbapenem-resistant Pseudomonas aeruginosa (CR-PA). Conclusion These data support the EUCAST SIE breakpoints for FEP and TZP. To optimize PTA at the SIE breakpoint for CAZ, prolonged infusion is required. Disclosures Christian M. Gill, PharmD, Cepheid: Grant/Research Support|Entasis: Grant/Research Support|Everest Medicines: Grant/Research Support|Shionogi: Grant/Research Support David P. Nicolau, PharmD, CARB-X: Grant/Research Support|Innoviva: Grant/Research Support|Innoviva: Honoraria|Merck: Advisor/Consultant|Merck: Grant/Research Support|Merck: Honoraria|Pfizer: Advisor/Consultant|Pfizer: Grant/Research Support|Pfizer: Honoraria|Shionogi: Advisor/Consultant|Shionogi: Grant/Research Support|Shionogi: Honoraria|Venatorx: Grant/Research Support </jats:sec
Synthesis and biological assessment of BUB1B inhibitors for the treatment of clear cell renal cell carcinoma
No full textClear cell renal cell carcinoma (ccRCC) presents substantial therapeutic challenges due to its molecular heterogeneity, limited response to conventional therapies, and widespread drug resistance. Recent advancements in molecular research have identified novel targets, such as BUB1B, which has been identified through global transcriptomic profiling and gene co-expression network analysis as critical in ccRCC progression. In this study, we synthesized 40 novel derivatives of TG-101209 to modulate BUB1B expression and activity, leading to the induction of apoptosis in Caki-1 cells. The molecular structures of all compounds were confirmed via 1H and 13C NMR and mass spectrometry. Computational docking studies were conducted using Schrödinger Maestro software. The efficacy of the compounds on cell viability was screened using the MTT assay and further validated by the LDH assay. The expression of the target protein BUB1B and apoptosis-related proteins was analyzed via western blotting. BUB1B activity was assessed through an enzymatic assay, and compound binding efficacy was evaluated using a cellular thermal shift assay (CETSA). The results indicated that four compounds (7h, 8h, 8i, and 8j) demonstrate stronger molecular interactions and better conformational fit within the target cavity, leading to improved binding affinity. These compounds also exhibited more potency in reducing the viability of Caki-1 cells compared to TG-101209. In particular, compound 8h was identified as the most effective, exhibiting the strongest inhibitory effect on BUB1B and inducing apoptosis. Compound 8h demonstrated intracellular binding with BUB1B, similar to TG-101209, but through a different binding moiety that destabilizes the BUB1B protein structure, whereas TG-101209 stabilizes it. In conclusion, compound 8h, by destabilizing BUB1B and inducing apoptosis, shows promise as a potent therapeutic candidate for clear cell renal cell carcinoma (ccRCC) treatment
The ability of C-reactive protein-albumin ratio to predict disease activity in ulcerative colitis
No full textUlcerative colitis (UC) is an incurable disease represented by relapse and remission. Noninvasive biomarkers are required to predict disease activation. This study aimed to identify noninvasive biomarkers, such as the c-reactive protein-albumin (CRP/ALB) ratio, platelet-lymphocyte ratio (PLR), and neutrophil-lymphocyte ratio (NLR), that might forecast disease activation in UC.This retrospective study included 443 participants: 192 patients with active UC, 166 in remission, and 85 healthy controls. Mayo Endoscopic Subscore was employed to assess endoscopic disease activity. Serum CRP, erythrocyte sedimentation rate (ESR), ALB levels, and complete blood count characteristics were documented. Three ratios of inflammation-related indicators were identified as CRP/ALB, PLR, and NLR.A positive correlation was found between ESR, CRP, neutrophil count, platelet count, levels of CRP/ALB, PLR, NLR, and endoscopic activity. The CRP/ALB ratio demonstrated more efficacy than the NLR and PLR in differentiating the UC patients from the controls (p = 0.007, p = 0.003, respectively) and the active group from the remission group (p < 0.001, p < 0.001, respectively). Regression analysis revealed that the CRP/ALB was significantly able to distinguish active UC from the remission group and the controls (p < 0.001, p < 0.001, respectively).The CRP/ALB ratio could be useful as an independent predictive biomarker for disease activity in UC
Synthesis and Characterization of Schiff Bases and Their Ag(I) Complexes Containing 2,5,6‐Trisubstituted Imidazothiadiazole Derivatives: Molecular Docking and In Vitro Cytotoxic Effects Against Nonsmall Lung Cancer Cell Line
No full textABSTRACTIn this study, four novels 2,5,6‐trisubstituted imidazothiadiazole derivative ligands and their Ag(I) complexes were synthesized and characterized using various spectroscopic analysis techniques. First, imidazo[2,1‐b][1,3,4]thiadiazole derivative (3) was obtained from the reaction of 5‐amino‐1,3,4‐thiadiazole‐2‐thiol with benzyl bromide in the presence of KOH in an ethanolic medium. In the next step, the resultant compound reacted sequentially with four substituted phenacyl bromide derivatives (4a–4d) under refluxed ethanol for 24 h to obtain substituted 2‐(benzylthio)‐6‐phenylimidazo[2,1‐b][1,3,4]thiadiazole derivatives (5–8). Compounds (9–12) were obtained by attaching a carbonyl group to carbon number 5 of the imidazothiadiazole group in these compounds with the help of Vilsmeier–Haack reagent. The resultant compounds were reacted in an ethanolic medium to synthesize the novel (13–16) ligands by adding ethylenediamine in a 1:2 molar ratio. The Ag(I) complexes of the resultant ligands were synthesized by mixing silver acetate with the ligands in a dimethyl sulfoxide medium to obtain (17–20) complexes. All the synthesized compounds were analyzed using FTIR, 1H NMR, 13C NMR, mass spectroscopy, magnetic susceptibility, ICP‐OES, and thermogravimetric analysis techniques. The study also investigates the in vitro cytotoxic effect of the ligands and complexes on A549 (nonsmall cell lung cancer) cells using the MTT assay and shows that the 13, 15, and 16 ligands, together with their complexes, exhibit potent cytotoxicity. In addition, in silico molecular docking simulations were conducted both to support the in vitro cytotoxicity experiments and to ascertain the active binding sites and interactions of the ligands and complexes on the EGFR receptor. The result indicates that ligands and complexes may serve as promising candidates for further investigation as anticancer agents.</jats:p
Ensuring Sustainability in Preschool Education in Rural Areas During the Pandemic Lockdown Period: Teachers’ Experiences
No full textThe COVID-19 pandemic profoundly disturbed preschool education in Turkey, necessitating a rapid shift to distance learning for over 1.5 million children. The Ministry of National Education has established programs such as the Educational Content Network in Turkey. Also, the Turkish Radio and Television Association has made the TRT Preschool Application available online to support ongoing distance learning for preschool children. Preschool education in rural parts of Turkey was deeply impacted by the COVID-19 pandemic. While previous research has examined the challenges of distance education broadly, there is a limited exploration of preschool teachers’ experiences during the pandemic lockdown, particularly in rural contexts in Turkey. To ensure sustainability in preschool education during the pandemic lockdown period, this study aimed to examine the experiences of preschool teachers who participated in distance education in rural areas. A qualitative case study was conducted with 10 teachers working in schools located in rural areas with diverse geographical difficulties scattered within the province near the Black Sea to obtain insights into the experiences of preschool teachers during the pandemic. The maximum variation sampling was utilized to select preschool teachers educating children between 45 and 72 months. To promote and facilitate individuals’ participation in the research, the semi-structured interviews were conducted via videoconferencing due to the lockdown. The content analysis was used to discover the meaning of the data. The study revealed that while teachers adapted their teaching methods to prioritize children’s well-being, disparities in digital access and socio-emotional issues within families created significant barriers to learning. The challenges encountered significantly impacted the children’s development in multiple areas. This study emphasized the need for improved infrastructure, providing extensive teacher training, and implementing robust support mechanisms to ensure the comprehensive growth of children in all domains during potential disasters. More research should be conducted to improve teachers’ skills in applying effective teaching strategies in virtual environments.</jats:p
Mapping the Anatomy of Novice-Generated Mistakes in Learning Programming
No full textProgramming has become very important in modern education. Research shows that exposing students to coding at a young age positively contributes to their academic, cognitive and professional development. However, students may make some mistakes during the programming process, which are considered a natural part of programming. In this context, the aim of this study is to classify various mistakes encountered by novice programmers while learning programming. For this purpose, a literature review was conducted, and it was found that there are basically two types of mistakes: strategic mistakes and knowledge-based mistakes. It was found that these mistakes are divided into groups within themselves. This book chapter recommends that researchers and practitioners conduct practical studies of the mistakes uncovered and conduct qualitative research in which the mistakes can be examined in greater depth.</jats:p
A meta-analysis of randomized controlled trials examining the effectiveness of carbetocin in reducing intraoperative blood loss during abdominal myomectomy
No full textAim: This study aimed to systematically review and meta-analyze randomized controlled trials (RCTs) assessing the clinical efficacy and safety of carbetocin compared to passive control (placebo or no treatment) in the context of abdominal myomectomy.
Methods: Six sources of information underwent screening until 13 April 2024. The risk of bias was assessed using the Cochrane Collaboration tool. The results were presented as mean difference (MD) or risk ratio (RR) along with a 95% confidence interval (CI) using a random-effects model.
Results: Five RCTs with 6 arms and 484 patients (carbetocin = 262 and control = 222) were analyzed. The overall risk of bias was "low" in two studies and "some concerns" in three studies. The carbetocin group exhibited significantly lower mean intraoperative blood loss (n = 6 arms, MD = -292.27 mL, 95% CI [-372.5, -212.03], p < 0.001, with very low certainty of evidence), mean change in hemoglobin (n = 6 arms, MD = -0.63 g/dL, 95% CI [-0.94, -0.33], p < 0.001, with low certainty of evidence), rate of blood transfusion (RR = 0.3, 95% CI [0.21, 0.44], p < 0.001, with very low certainty of evidence), and mean operation time (n = 5 arms, MD = -22.98 min, 95% CI [-38.93, -7.02], p < 0.001, with low certainty of evidence). There was no significant difference between both groups regarding the mean hospital stay (n = 2 arms, MD = -0.1 days, 95% CI [-0.27, 0.06], p = 0.21). The sensitivity analyses demonstrated robustness across all outcomes. No major toxicities were reported.
Conclusion: Carbetocin use was tolerable and associated with considerable declines in intraoperative blood loss and related complications compared with passive control intervention during abdominal myomectomy