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In recent years, the International GNSS Service (IGS) has put a lot of effort into reprocessing and analyzing all GNSS data collected by the IGS contributors since 1994. Taking advantage of new software capabilities and using state-of-the-art models, the goal is to ensure a consistent set of products such as orbits, station coordinates and Earth orientation parameters. Using these official IGS “Repro3” products, the new realization of the International Earth Reference Frame (ITRF2020) and new modelling in the just released version 5.4 of the Bernese GNSS Software, the Canadian Geodetic Survey (CGS) is reprocessing GPS data from 2000 to 2022 for all available public regional networks in Canada and the neighbouring areas of the U.S. and Greenland to realize the new North American Terrestrial Reference Frame of 2022 (NATRF2022) in Canada. In order to densify the network of continuous stations and improve the national crustal velocity model for propagating coordinates to different epochs, GPS data for Canadian commercial RTK networks are also being processed. We describe the key aspects of our data reprocessing using the orbits and weekly coordinates from IGS Repro3 results, with particular emphasis on the impact of transitioning from a global reference frame alignment to a regional one for more efficient processing and to resolve some issues occurring with the use of global stations., The 28th IUGG General Assembly (IUGG2023) (Berlin 2023)

Background: B-cell lymphoma 2 (BCL-2) and BCL-2 associated X (BAX) polymorphisms are important in the apoptosis process, response to treatment and survival in Acute Lymphoblastic Leukemia (ALL) patients. We aimed to investigate the effect of these genes with other predictors corresponding to the survival of ALL patients with an appropriate frailty survival model. Methods: Our study was performed in 2020 on sixty-two cases of childhood aged 3-16 (year) with ALL disease who were selected by convenience sampling from the two hospitals of Tabriz, Iran. RFLPPCR method was used for genotyping the promoter region of the BAX and BCL-2 genes. We used different frailty survival models, to control heterogeneity between individuals due to unmeasured factors affecting their survival. All analyses were implemented using Stata 16. Results: Based on the result of log-logistic model along with frailty gamma, the proportional odds (standard error) of survival for a CC allele of BCL-2 patient compared to a AA allele patient were 6.0 (1.47); P

Background: Sore throat after endotracheal intubation during general anesthesia is a common complaint of patients especially in children. Strabismus surgery in one of the common procedures in child patients. The present study investigates the use of intratracheal ketamine administration in reducing sore throat after strabismus surgery. Methods: This study was performed on 60 patients undergoing elective strabismus surgery under general anesthesia from December 2019 to February 2020 in Farabi eye hospital, Tehran University of medical sciences, Tehran, Iran. These cases were referred to our center for strabismus operation from other centers of our country. Patients were randomly divided into two equal groups. After sufficient depth of anesthesia with sevoflurane and injection of fentanyl, endotracheal intubation was performed. In the control group, the endotracheal tube was inserted and 2 ml of ketamine solution at a concentration of 5 mg/ml were administered in endotracheal tube. The severity of sore throat, length of stay in recovery, incidence of delirium in recovery, satisfaction of recovery nurses and their parents and other complications were compared between the two groups. Results: Mean age, sex and weight were not significantly different between the two groups and were comparable. The mean duration of stay in recovery was higher in the case group than in the control group. The mean postoperative sore throat was significantly higher in the control group. Moreover, the mean incidence of delirium in the postoperative phase was higher in the case group. Besides, the rate of nurse satisfaction in the control group was higher than the case group. The incidence of bronchospasm, laryngospasm, and postoperative nausea and vomiting was not significantly different between the two groups. Conclusion: Intratracheal ketamine can reduce postoperative sore throat and the need for postoperative analgesic medications. Postoperative complications were not increased with this strategy, but the length of recovery stay increased in these patients.

Background: Cataract surgery is one of the most common surgeries in the world, especially in elderly patients, and often performed topically with sedative agents. Ketamine is one of the most commonly used agents and the effect of different doses on intraocular pressure is in dispute. The present study investigates the effect of a low dose of ketamine on intraocular pressure in patients undergoing cataract surgery. Methods: This case-control study was performed in Farabi Hospital, Tehran University of Medical Sciences from January 2020 to February 2020. In this study 92 patients undergoing cataract surgery were randomly divided into two groups of 46 patients. Patientschr('39') intraocular pressure and blood pressure were measured at baseline, and then all patients received 1 mg midazolam and 1 μg/kg fentanyl before initiation of the study. In the case group, 0.15 mg/kg ketamine was injected intravenously. Intraocular pressure and blood pressure of all subjects were measured three minutes after injection of sedation. Also, postoperative pain, need for opioids and, postoperative nausea and vomiting were compared between the two groups. Results: There was no significant difference in age, sex and weight between the two groups. Mean intraocular pressure in both groups was not significantly different at baseline. The trend of changes in intraocular pressure was lower in both groups after sedation and there was no statistically significant difference between the two groups. After sedation injection, the mean arterial blood pressure changes in the control group were decreasing while in the case group showed an increasing trend and this difference was statistically significant. Five patients in the control group and one in the case group complained of moderate to severe pain postoperatively. There was no significant difference between the two groups regarding nausea and vomiting and the need for postoperative opioids. Conclusion: Low-dose ketamine administration had no significant effect on intraocular pressure and did not cause side effects of ketamine such as nausea, vomiting and hallucinations and it may improve the hemodynamic stability of patients if they are injected with sedative medications.

Background: Cataract is one of the most common eye diseases especially in elderly patients and most of these patients require surgery. In the process of sedation, different drugs are used, each with its advantages and disadvantages. Dexmedetomidine is one of the drugs that has recently received special attention for sedation. In this study, we compared the drug combination of dexmedetomidine-fentanyl with midazolam-fentanyl in cataract surgery. Methods: In a case-control study, the patients who underwent cataract surgery by a surgeon with topical anesthesia and sedation techniques were included in the target group. Seventy patients were divided into two groups of 35 according to a random number table. One group received dexmedetomidine-fentanyl (dexmedetomidine group) and the other received midazolam-fentanyl (midazolam group). Age, sex, weight, systolic and diastolic blood pressure, heart rate, patient sedation, surgeon satisfaction, recovery nurse satisfaction, and postoperative nausea and vomiting were compared between the two groups. The study was performed in the Farabi Hospital, Tehran, Iran, from October to November 2019. Results: Patients in the two groups were similar in age, sex, weight, and preoperative hemodynamic variables. There was no significant difference in preoperative systolic and diastolic blood pressure between the two groups (P=0.150). However, those who received dexmedetomidine had significantly lower intraoperative heart rate (P

Background: Nausea and vomiting is one of the most common complications after the strabismus surgery. In this study, we evaluated the efficacy of atropine versus ondansetron administration on the incidence of postoperative nausea and vomiting and duration of recovery stay in patients undergoing this procedure. Methods: In this case-control study, 90 patients between 3 to 30 years old who were candidates for elective strabismus surgery in Farabi Eye Hospital, Tehran University of Medical Sciences, Tehran, Iran, from February to April 2019, were randomly divided into three groups (placebo, ondansetron and atropine group). Patients who had taken hypnotic drugs while entering the operating room were excluded. In all patients, after arriving into the operating room and installation of standard monitoring equipment and peripheral vein implantation, anesthesia was induced by receiving 0.05 mg/kg midazolam, fentanyl 1 μg/kg and propofol 2.5 mg/kg. After induction of anesthesia, placebo group was compared with ondansetron group and atropine group that received 0.1 mg/kg ondansetron and 30 µg/kg atropine, respectively. The rate of postoperative nausea and vomiting, duration of recovery stay and satisfaction of recovery nurses were recorded and compared between groups. Results: There was no statistically significant difference between the three groups in terms of mean age, weight, and gender. It seems that group matching is appropriate and there are no confounding factors for demographic variables. Administration of atropine and ondansetron significantly reduces the incidence of nausea and vomiting postoperatively and in recovery. There was no significant difference in the incidence of nausea and vomiting between the atropine and ondansetron groups. Duration of recovery stay was decreased after ondansetron and atropine administration versus control group. Postoperative laryngospasm and bronchospasm were not observed in any of the three groups after surgery and at the time of recovery. The satisfaction of recovery nurses in both atropine and ondansetron groups were higher than control group. Conclusion: It seems that the administration of atropine as much as ondansetron can be effective in reducing the incidence of postoperative nausea and vomiting and the length of recovery stay in patients who undergoing strabismus surgery.

Background: Cataract is one of the most common eye diseases especially in children and adolescents in two age ranges, and many of these patients need to surgery throughout life. The purpose of this study was to compare the efficacy and side effects of midazolam-ketamine and midazolam-fentanyl for sedation in adult cataract surgery. Methods: In this study, which was a case-control study, 80 patients were referred to Farabi Hospital in Tehran from November to December 2018 for cataract surgery and underwent surgery. The patients were divided into two groups (n=40). In this study the method of using midazolam-ketamine (ketamine group) was compared with the combination of midazolam-fentanyl (fentanyl group). The hemodynamic variables such as blood pressure and heart rate before surgery were measured and then measured every 5 minutes during operation and were recorded. In addition to hemodynamic variables, other variables such as agitation, surgeon satisfaction, recovery nurse satisfaction, degree of oxygen saturation during surgery, and nausea and vomiting were compared between the two groups. Results: In this study, 18 patients (45%) of fentanyl group and 17 patients (42.5%) of ketamine group were female. Patients in the two groups had similar demographic distribution before surgery. In this study about blood pressure after surgery, from 80 patients, 22 cases had blood pressure below 119.79 mmHg, of which 3 (13.6%) cases were in ketamine group and 19 cases (86.4%) in fentanyl group. In general, 7.5% of ketamine group and 47.5% of fentanyl group had a blood pressure lower than 119.79 mmHg. Hemodynamic changes and hypotension after sedation was more in fentanyl group. Two groups did not differ in terms of heart rate, arterial oxygen saturation during surgery, surgeon satisfaction during surgery, and postoperative nausea and vomiting. Conclusion: Administration of ketamine-midazolam versus fentanyl-midazolam in patients who underwent cataract surgery by sedation led to more stable hemodynamic variables intraoperatively and other side effects such as heart rate, oxygen saturation, surgeon satisfaction, nausea and vomiting were similar between two groups.

Reinforced composites are used in many industrial and multi-functional applications. The efficiency of the reinforcements depends mainly on the aspect ratio, material properties, and the adhesion between matrix and reinforcement. Particularly, high aspect ratio fillers and inclusions have gained popularity due to their unique material and geometrical features, where a fundamental understanding of composites hierarchical structure and behavior is crucial for the optimal design and performance. There is however a lack of robust numerical modeling frameworks that are able to accurately represent composites with high aspect ratio reinforcements. Ideally the expensive mesh generation of the standard finite element method or the simplifying assumptions adopted by smeared type or mean-field approaches should be avoided.A group of numerical techniques here referred to as "embedded methods" eliminate mesh conformity restrictions and significantly reduce the computational cost of the standard finite element method, while still benefiting from the advantages of a direct numerical analysis. In formulating the embedded models, enrichment techniques and different element technologies are considered, and physical assumptions are investigated. Limitations of the classical embedded models are highlighted through numerical examples, on the basis of which possible enhancements are discussed. We specifically highlight the important roles of field gradients continuity/discontinuity and the element size, order, and regularity extensions on the smoothness of the solutions.A computationally efficient embedded model is then applied to the study of failure and inclusion orientation effects in planar composites. A detailed study is also performed for dense fiber-reinforced composites, where homogenized mechanical properties are extracted and various forms of neutrality of thin fibers are demonstrated. In this context, a part of this thesis is dedicated to one-to-one comparisons between results obtained using the standard finite element method and embedded techniques. This led to a range of model and geometry parameters under which predictions of embedded technique are reliable. Comparisons are reported in terms of homogenized properties and local field variables, namely relative displacement between inclusions and matrix (slips).Finally as a preliminary step towards multi-functional fiber-based structural batteries, an electro-chemical system characterized by composite cathode in a half cell configuration is considered. The main point of difference with common composite batteries is that active material particles are cast in form of high aspect ratio fibers, which are efficiently discretized by use of the embedded technique. A discrete definition of fibers, unlike the case of mean-field approaches, allows to define local fields and interfacial conditions between fibers and electrolyte and is crucial for the accurate modelling of a battery cell with fiber-based electrodes.

Background: BCL-2 is the most important anti-apoptotic regulator and Bax is a pro-apoptotic protein. The status of these parameters or the ration of BCL-2 to BAX is important in malignant cell fate as well as normal cells. Methods: Sixty-two ALL patients and 62 healthy sex-and age-matched controls were studied. After genotyping, the promoter region of the BAX and BCL-2 genes by RFLP-PCR method the patients were classified in nine prognostic groups, after that, the overall survival ratio of each score was compared with others pair-wise or between groups. Results: The frequencies of the AA, AC, CC alleles of the BCL-2 C-938A polymorphism in patient group were 33 (53.23%), 18 (29.03%), 11 (17.74%), and in the control group were 13 (21.0%), 27 (43.5%), 22 (35.5%), respectively (P=0.003). Also, the frequencies of AA, AG, GG alleles of the BAX G-248A SNP were 15 (24.2%), 24 (38.7%), 23 (37.1%) in ALL group and 13 (21.0%), 25 (40.3%), 24 (38.7%) (p>0.05) in the control group. The survival time estimation and ratio were significantly different between different SNPs in BCL-2 (P=0.002). Conclusion: These findings showed that the BCL-2 promoter region polymorphism is more reliable than BAX gene promoter polymorphism in any ALL scoring system. But the establishment of complete scoring system requires further more clinical and laboratory findings along with genetic polymorphisms is necessary