Preliminary Results of an Astri/UWM EGNSS Receiver Antenna Calibration Facility.

In 2019, the University of Warmia and Mazury in Olsztyn, in cooperation with Astri Polska, started a European Space Agency (ESA) project. The purpose of the project is the development and implementation of a field calibration procedure for a multi-frequency and multi-system global navigation satellite system (GNSS). The methodology and algorithms proposed in the project are inspired by the "Hannover" concept of absolute field receiver antenna calibration; however, some innovations are introduced. In our approach, the antenna rotation point is close to the nominal mean phase center (MPC) of the antenna, although it does not coincide with it. Additionally, a National Marine Electronics Association local time zone (NMEA ZDA) message is used to synchronize the robot with the GNSS time. We also propose some modifications in robot arm movement scenarios. Our first test results demonstrate consistent performance for the calibration strategy and calibration procedure. For the global positioning system (GPS) L1 frequency, the calibration results show good agreement with the IGS-type mean values. For high satellite elevations (20°-90°), the differences do not exceed 1.5 mm. For low elevation angles (0°-20°), the consistency of the results is worse and the differences exceed a 3 mm level in some cases.

Complications after laparoscopic gastric banding in own material.

INTRODUCTION: Complications after bariatric procedures are the most difficult to diagnose among all complications in abdominal surgery. Furthermore, they are extremely difficult to treat conservatively and surgically. Laparoscopic treatment of complications after bariatric procedures requires great skills. Complications after laparoscopic adjustable gastric banding (LAGB) are remarkably diverse. AIM: Presentation of complications after LAGB in our own material. MATERIAL AND METHODS: From 2005 to 2010, in the 1(st) Department of General and Endocrine Surgery, in 110 patients adjustable gastric banding was applied. All procedures were conducted laparoscopically. The group consisted of 76 women (69.1%) and 34 men (30.9%). The average age of women was 37.7 ±13.80 years old. The average age of men was 38.9 ±11.50 years old. The average body mass was 128.5 ±24.35 kg for women and 125.4 ±23.60 kg for men. The average body mass index (BMI) for women was 44.08 ±3.03 kg/m(2) and for men 43.66 ±2.90 kg/m(2). The average waist circumference was 113.5 ±12.75 cm in women and for men it was 124.40 ±14.8 cm. RESULTS: In the analysed material, which consisted of 110 patients after LAGB, 36% developed at least 1 complication. Among early complications, injury of diaphragm, pneumothorax, pleural empyema, gastric perforation and thrombophlebitis were observed. Among late complications, oesophagitis, infections around the port, migration of the gastric band into the gastric lumen, band slippage, vomiting and lack of body mass loss were observed. The most common reasons for the removal of the band were band slippage, its migration to the gastric lumen and extension of the gastric reservoir. CONCLUSIONS: The LAGB is a relatively easy procedure with a short time of performance and short hospitalization. However, it can bring the risk of intraoperative, perioperative and late complications which require surgical intervention. The present research results are comparable to world data. Complications after LAGB were observed the most frequently in the first years of application of the procedure.

The influence of laparoscopic adjustable gastric banding and laparoscopic sleeve gastrectomy on weight loss, plasma ghrelin, insulin, glucose and lipids.

The aim of this study was to assess the impact of laparoscopic gastric banding and laparoscopic sleeve gastrectomy on the concentration of ghrelin, insulin, glucose, triglycerides, total and HDL-cholesterol, as well as AST and ALT levels in plasma in patients with obesity. The research includes 200 patients operated using LAGB (34 men average age 37.0 ± 12.6 years and 66 women average age 39.18 ± 12.17 years) and LSG (48 men average age 47.93 ± 9.24 years and 52 women, 19 ± 9.33 years). The percentage of effective weight loss, effective BMI loss, concentration of ghrelin, insulin, glucose, triglycerides, total cholesterol, HDL-cholesterol, LDL-cholesterol, ALT, AST and HOMA IR values was taken preoperatively and at 7th day, 1 month, 3 and 6 months after surgery. Both after LSG and after LAGB, statistically significant reduction in BMI, serum insulin, glucose and HOMA IR was noticed in comparison to the preoperative values. Post LAGB, patients showed an increase of ghrelin, while LSG proved ghrelin decreased. Correlations between glucose and BMI loss, and between insulin and BMI loss in both cases are more favorable in the LSG group. Lipid parameters, AST and ALT have undergone declines or increases in the particular time points. Both techniques cause weight loss and this way lead to changes in the concentration of ghrelin, as well as to the improvement of insulin, glucose, cholesterol and triglycerides metabolism. They reduce metabolic syndrome and multiple comorbidities of obesity.

Impact of laparoscopic sleeve gastrectomy on body mass index, ghrelin, insulin and lipid levels in 100 obese patients.

INTRODUCTION: A high percentage of patients benefit from bariatric procedures in terms of metabolic effect and substantial body mass reduction. These procedures improve glucose metabolism leading to the amelioration or complete resolution of type 2 diabetes, reduction of insulin resistance and alleviation of metabolic syndrome effects. AIM: To assess the impact of laparoscopic sleeve gastrectomy (LSG) on the plasma levels of ghrelin, insulin, glucose, triglycerides, total cholesterol, high-density lipoprotein (HDL) and low-density lipoprotein (LDL) fractions as well as aspartate and alanine transaminases in patients with obesity. MATERIAL AND METHODS: One hundred patients who underwent laparoscopic sleeve gastrectomy in our centre between 2005 and 2009 were included in the study. Among them were 48 males with an average age of 47.93 ±9.24 years and 52 females with an average age of 44.19 ±9.33 years. Percentage excess weight loss (%EWL), percentage excess body mass index (BMI) loss (%EBL), ghrelin, insulin, glucose, triglycerides, cholesterol, HDL, LDL, alanine transferase (ALT), and asparagine transferase (AST) were measured preoperatively and on the 7(th) day then 1, 3 and 6 months after the surgery. RESULTS: Statistically significant reduction in postoperative BMI, plasma levels of glucose and insulin as well as the homeostatic model assessment insulin resistance (HOMA IR) score was noted in comparison to the preoperative values. The ghrelin levels decreased. Lipid profile, AST and ALT levels varied depending on the particular time points. CONCLUSIONS: Laparoscopic sleeve gastrectomy reduces body mass and leads to the decrease of concentration of ghrelin in plasma as well as to the improvement of metabolism of insulin, glucose, cholesterol and triglycerides. The above changes alleviated symptoms of metabolic syndrome and obesity related co-morbidities.