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The dimensional, geometrical, thermal and tool deflection errors which have a big portion of the overall error of machined parts need more attention in precision of components produced by using CNC machine tools. As a result, it is essential to simulate and compensate the errors in the machined components in order to increase accuracy of machined parts. In order to simulate and analyse the real manufactured components in virtual environments, virtual machining systems are proposed. In this paper, application of virtual machining system is investigated in order to simulate and compensate dimensional, geometrical, thermal and tool deflection errors in 5-axis milling operations of free form surfaces. The volumetric error vectors regarding the dimensional, geometrical, thermal and tool deflection errors at each cutting tool location throughout the machining pathways are calculated and compensated utilising the study's created virtual machining technology. In order to validate the study, a sample workpiece free from surfaces is milled by using the 5-axis CNC machine tool. The machine part is then measured by suing the CMM machine in order to obtain the dimensional, geometrical, thermal and tool deflection errors during milling operations of free form surfaces. Thermal sensors are also installed to the different locations of CNC machine tool in order to measure the thermal error of CNC machine tool during machining operations. Finally, in order to improve accuracy in 5-axis milling operations of free form surfaces, new cutting tool paths regarding the compensated volumetric errors of dimensional, geometrical, thermal, and tool deflection errors are generated. As a result, by utilising the proposed virtual machining system in the research work, precision as well as reliability during 5-axis milling operations of free form surfaces can be enhanced. [ABSTRACT FROM AUTHOR]

Concrete, ceramics, rocks, metal-matrix composites, titanium alloys and other hard-to-cut materials are frequently cut using the non-traditional cold processing method known as abrasive water jet machining (AWJM). A virtual machining system is proposed in the study to minimize roughness of surface and residual stress during AWJM of titanium alloy Ti6Al4V. The water and workpiece are simulated in virtual environments using the smoothed particle hydrodynamics (SPH) approach and finite element method, respectively. Then, the Johnson–Cook law model of titanium alloy is used to obtain the cutting temperature during cutting operations. To calculate residual stress during the AWJM operations, the finite element method is then utilized. The Taguchi optimization method is implemented to minimize surface roughness and residual stress in AWJM operations. Thus, the optimized machining parameters such as water jet pressure, traverse speed, abrasive mass flow rate and standoff distance are calculated to minimize the surface roughness and residual stress during the AWJM of titanium alloy Ti6Al4V. Experimental and computational examinations are carried out in order to validate the effectiveness and efficiency of proposed virtual machining system in minimization of surface roughness and residual stress during abrasive waterjet cutting of titanium alloy Ti6Al4V. As a result, by using the optimized machining parameters, 23.7% and 27.1% reduction in the measured and predicted residual stress of sample machined part are obtained. Also, the sample machined part's surface roughness is reduced by 26.7% and 27.9%, for the measured and predicted surface roughness of sample machined part, respectively. So, the quality and reliability of the machined parts can be enhanced using the developed virtual machining system in the study to minimize the surface roughness and residual stress in AWJM operations. [ABSTRACT FROM AUTHOR]

The titanium alloys are widely used in aeronautical engineering and medical device materials due to exceptional mechanical properties such as tensile resistance and toughness of fractures. High thermo-mechanical loads occur in metal cutting of Titanium alloy Ti6Al4V, which can decrease life of cutting tool and increase cost of part production. In this paper, the coolant effects on the cutting temperature, surface roughness and tool wear are investigated by using the developed virtual machining system. The cutting forces during turning operations of Ti6Al4V alloy are accurately calculated in order to be used in calculation of cutting temperature and tool wear. The modified Johnson–Cook methodology is utilized to obtain the cutting temperatures along machining paths. Then, the Coupled Eulerian-Lagrangian (CEL) approach is investigated to predict and evaluate the effects of coolants on the cutting temperature in turning operations of Ti6Al4V alloy. The finite element approach is employed to predict tool wear by using the Takeyama–Murata analytical model and modifying the cutting tool geometry during the chip production process. To verify the developed methodology in the study, the results of experiments for the measured cutting temperatures, surface quality and wear rate are compared to the results of virtual machining system obtained by the finite element simulation. Thus, utilizing the proposed virtual machining system in the study, cutting temperatures, surface quality and tool wear during the turning operations of Ti6Al4V alloys with and without coolant can be accurately predicted to enhance the accuracy as well as productivity in the CNC machining operations. [ABSTRACT FROM AUTHOR]

Virtual manufacturing is one of the key components of Industry 4.0, the fourth industrial revolution, in improving manufacturing processes. Virtual manufacturing enables manufacturers to optimize their production processes using real-time data from sensors and other connected devices in Industry 4.0. Web-based virtual manufacturing platforms are a critical component of Industry 4.0, enabling manufacturers to design, test, and optimize their processes collaboratively and efficiently. In Industry 4.0, radio frequency identification (RFID) technology is used to provide real-time visibility and control of the supply chain as well as to enable the automation of various manufacturing processes. Big data analytics can be used in conjunction with virtual manufacturing to provide valuable insights and optimize production processes in Industry 4.0. Artificial intelligence (AI) and virtual manufacturing have the potential to enhance the effectiveness, consistency, and adaptability of manufacturing processes, resulting in faster production cycles, better-quality products, and lower prices. Recent developments in the application of virtual manufacturing systems to digital manufacturing platforms from different perspectives, such as the Internet of things (IoT), big data analytics, additive manufacturing, autonomous robots, cybersecurity, and RFID technology in Industry 4.0, are discussed in this study to analyze and develop the part manufacturing process in Industry 4.0. The limitations and advantages of virtual manufacturing systems in Industry 4.0 are discussed, and future research projects are also proposed. Thus, productivity in the part manufacturing process can be enhanced by reviewing and analyzing the applications of virtual manufacturing in Industry 4.0. [ABSTRACT FROM AUTHOR]

Background: Obesity is one the most prevalent diseases all around the world. Some studies have shown a relationship between obesity and the worsening of rheumatic disorders. Higher rates of surgical complications might also be seen among these patients. Methods: This retrospective-descriptive study was performed on 25 patients with rheumatic disease referred to Loghman Hakim Hospital (Tehran- Iran) and candidates for bariatric surgery (laparoscopic Roux-en-Y gastric and laparoscopic sleeve gastrectomy) from 2018 to 2020. Duration of hospitalization after surgery and history of post-operation surgical and rheumatic complications were assessed. Patients were followed through 6 months after surgery. Results: The age (Mean±SD) of recruited patients was (38.4 ±10.0) years. The mean body mass index was 45.54 kg/m2 with the minimum and maximum values of 37.5 kg/m2 and 56.5 kg/m2. Among them, the prevalence of rheumatic disorders was rheumatoid arthritis 32%, psoriasis 28%, gout 16%, lupus erythematosus 8%, and other rheumatologic disorders 16%, respectively. One patient had a surgical complication that was a port site infection. One patient had a relapse of gout and other patients had remission and also, their therapeutic drugs were discontinued or reduced. Conclusion: Patients with rheumatic disorders revealed no higher surgical complication rate after bariatric surgery, and bariatric surgery helped disease remission among these patients. [ABSTRACT FROM AUTHOR]

The residual stress and surface roughness enhancement of ground surfaces can decrease the lifetime of workpiece by reducing its fatigue life. It is critical to accurately predict and minimize the residual stress and surface toughness of ground surfaces in order to enhance efficiency of part production using grinding operations. A virtual machining system is developed in the research work to minimize the surface integrity and residual stress during grinding operations of Inconel 718. The cutting temperature during grinding operations is calculated using the Inconel alloy Johnson–Cook law models. Then, using the finite element method, residual stress during the grinding operation is estimated. Utilizing the established virtual machining method, the surface roughness is predicted in the study. Using the Taguchi optimization approach, the grinding parameters of depth of cut and feed velocity are optimized in order to reduce surface roughness as well as residual stress throughout grinding operations on Inconel 718 superalloy. To confirm the effectiveness of the developed technique in the study, simulation and experimentation are conducted. As a result, the quality as well as reliability of the ground surfaces can be enhanced by using the developed virtual machining system in the study to minimize the surface roughness and residual stress of produced parts using grinding operations. [ABSTRACT FROM AUTHOR]

The Reynolds number of turbine blades can be reduced by decreasing the surface roughness of the blades, which decreases energy loss in energy production systems. Due to the challenges of the polishing process in reducing roughness of machined blades, the application of optimized machining parameters to decrease surface roughness is a practical solution. Virtual machining system is explored in this research to improve the efficiency of machined parts. The aim of this research is to provide a virtual machining system that can predict and effectively reduce roughness in gas turbine blade 5-axis machining operations. The machining parameters were optimized using Genetic algorithm to reduce surface roughness. The turbine blades were machined using a 5-axis CNC machine tool, and the surface roughness of the machined parts was measured using a CMM machine to validate the developed methodology in the study. The optimized machining parameters result in a 26.2% reduction in observed surface roughness and a 27.3% reduction in expected surface roughness in the machined blades. The developed virtual machining system can be used to improve the surface quality of machined turbine blades and hence improve the efficiency of gas turbines during the power production in gas turbines. [ABSTRACT FROM AUTHOR]

The 5-axis CNC machine tools are used for manufacturing free form surfaces of sophisticated parts such as turbine blades, airfoils, impellers, and aircraft components. The virtual machining systems can be used in order to analyze and modify the 5-axis CNC machine tools operations. Cutting forces and cutting temperatures induce deflection errors in thin-walled structures such as impeller blades through machining operations. Thin-walled impeller blades' flexibility can result in machining errors such as overcutting or undercutting. So, decreasing the deflection error during machining operations of impeller blades can achieve the desired accuracy in produced parts. Optimized machining parameters can be obtained to minimize the deflection of machined impeller blades. In terms of precision and efficiency enhancement in component production processes, a virtual machining system is developed to predict and minimize deflection errors of 5-axis milling operations of impeller blades. The deflection error in machined impeller blades is calculated by using finite element analysis. The optimization methodology based on the genetic algorithm is applied to minimize the deflection error of impeller blades in machining operations. To validate the integrated virtual machining system in the study, the impeller is milled by using a 5-axis CNC machine tool. The CMM machine is used in order to measure and analyze deflection error in the machined impeller blades. As a result, by using the developed virtual machining system in the study, accuracy and efficiency in 5-axis milling operations of impellers can be increased. [ABSTRACT FROM AUTHOR]

Composite materials are used to produce multi-objective structures such as fluid reservoirs, transmission pipes, heat exchangers, pressure vessels due to high strength and stiffness to density ratios and improved corrosion resistance. The mathematical concepts can be used to simulate and analyze the generated mechanical and thermal properties of composite materials regarding to the desired performances in actual working conditions. To solve and obtain the exact solution of the developed nonlinear differential equations in the composite materials, analytical methods can be applied. Mechanical and thermal analysis of complex composite structures can be numerically analyzed using the Finite Element Method (FEM) to increase performances of composite structures in different working conditions. To decrease failure rate and increase performances of composite structures under complex loading system, thermal stress and effects of static and dynamic loads on the designed shapes of composite structures can be analytically investigated. The stresses and deformation of the composite materials under the complex applied loads can be calculated by using the FEM method in order to be used in terms of safety enhancement of composite structures. To increase the safety level as well as performances of the composite structures in different working conditions, crack development in elastic composites can be simulated and analyzed. To develop and optimize the process of composite deigning in terms of mechanical as well as thermal properties under different mechanical and thermal loading conditions, the advanced machine learning systems can be applied. A review in recent development of composite materials and structures is presented in the study and future research works are also suggested. Thus, to increase performances of composite materials and structures under complex loading systems, advanced methodology of composite designing and modification procedures can be provided by reviewing and assessing recent achievements in the published papers. [ABSTRACT FROM AUTHOR]

Cutting tool wear during drilling operations can cause damage to cutting tools, machine tools, and workpieces which should be analyzed and minimized. Cutting tool wear impacts not just tool life but also the quality of the final product in terms of dimensional accuracy and surface integrity. High mechanical and thermal loads are generated during drilling operations of difficult-to-cut materials such as Ti-6Al-4V alloy which can reduce the life of cutting tool during chip formation process. Thus, to increase the accuracy of drilled parts from titanium alloy Ti6-Al-4V, the cutting tool wear during drilling operations should be accurately predicted in order to be minimized. Application of virtual machining systems is developed in the study in order to predict and minimize the cutting tool wear during drilling operations of titanium alloy Ti-6Al-4V. To predict the tool wear during drilling operations, cutting forces and temperature are calculated. Then, the finite element method (FEM) is utilized to predict the tool wear using the analytical model of Takeyama–Murata and updating the cutting tool geometry during chip formation process. To minimize the cutting tool wear during drilling operations, the optimum drilling parameters of feed rate and spindle speed are obtained using the Taguchi method-based response surface analysis algorithm. As a result, optimized drilling parameters are used in order to minimize the cutting tool wear during drilling operations. To validate the study, the experimental works are implemented to the sample workpiece from titanium alloy Ti6-Al4-V and the values of tool wear are then measured. To present the effectiveness of the proposed virtual machining system in minimization of cutting tool wear, the obtained results with and without optimized machining parameters are evaluated and compared. So, precision and productivity in drilling operations of titanium alloy Ti6-Al4-V can be enhanced using the developed virtual machining system in the study. [ABSTRACT FROM AUTHOR]

Background: Hydatid cyst, caused by the larvae of Echinococcus granulosus, is one of the most severe cestode infections occurring in Iran. The liver is the most commonly involved organ. The present study was carried out to review the demographic of 20 years surgically treated hydatic cysts. Methods: Ninety-eight patients were enrolled in the study. Demographic features, time of surgery, cyst size, and albendazole usage have been reviewed from the medical records of patients in Loghman Hakim Hospital, Tehran, Iran, from 2001 to 2021. Statistical analysis was performed to find any correlation between the uses of concurrent albendazole with surgical procedure. Results: Of 98 patients with hydatid cyst, 57 (58.2%) were female. The mean age of patients was 39.4 ±18.7 yrs, and the mean surgery time was 217.5 ± 81.4 minutes. Regarding the infection site, the liver (60.2%) and lungs (22.4%) were the most affected organs, respectively. 56.1% of patients had one cyst, and 42.9 % had two or more cysts. 20.4% of them had taken albendazole before surgery, but 86.7 % took it after the operation. No recurrent cysts were seen among 91.8% of them, but 8.2% mentioned suffering from a recurrent cyst. 85.7% of those recurrent cases did not receive albendazole before surgery, and 75% of recurrent cases after surgery did not take albendazole (P<0.05). Conclusion: Administration of albendazole before and after the operation was significantly related to reduced recurrence, bleeding, morbidity, and even the time of surgery. [ABSTRACT FROM AUTHOR]

The optimization process is applied to the machining operations in order to provide continual improvement in accuracy and quality of produced parts. The effects of machining parameters in milling operations, such as spindle speed, depth of cut and feed rate are investigated in order to minimize the surface roughness as well as the time of machining process. The effective machining parameters, such as depth of cut, feed rate and spindle speed in turning operations are investigated to minimize the surface roughness as well as the time of machining process. Also, machining parameters, such as peak current, gap voltage, duty cycle and pulse on time in Electro Discharge Machining (EDM) operations can be optimized in order to obtain the optimized material removal rate, tool wear, and surface roughness in part production process. To improve material removal rate, surface roughness, and spark gap in part production process using the wire EDM operations, machining parameters, such as spark on time, spark off time, input current are studied and optimized. To calculate optimized machining parameters, different optimization methods, such as Taguchi method, fuzzy logic algorithm, artificial intelligence, genetic algorithm, artificial neural networks, artificial bee colony algorithm, ant colony optimization and harmony search algorithm are used. As a result, time and cost of accurate production can be reduced to increase productivity in part production process using machining operations. In this paper, a review of machining parameter optimization is presented and future research works are also suggested. The main aim of the study is to review the challenges and limitations of the optimization techniques used in optimizing machining parameters. It has been observed that the research field can be moved forward by reviewing and analyzing recent achievements in the published papers. [ABSTRACT FROM AUTHOR]

To simulate and analyse the real machined parts in virtual environments, virtual machining systems are applied to the production processes. Due to friction, chip forming, and the heat produced in the cutting zone, parts produced using machining operation have residual stress effects. The machining force and machining temperature can cause the deflection error in the machined turbine blades, which should be minimized to increase the accuracy of machined blades. To minimize the residual stress and deflection error of machined parts, optimized machining parameters can be obtained. In the present research work, the application of a virtual machining system is presented to predict and minimize the residual stress and deflection error in a five-axis milling operations of turbine blades. In order to predict the residual stress and deflection error in machined turbine blades, finite element analysis is implemented. Moreover, to minimize the residual stress and deflection error in machined turbine blades, optimized parameters of machining operations are obtained by using a genetic algorithm. To validate the research work, experimentally determining residual stress by using a X-ray diffraction method from the machined turbine blades is compared with the finite element results obtained from the virtual machining system. Also, in order to obtain the deflection error, the machined blades are measured by using the CMM machines. Thus, the accuracy and reliability of machined turbine blades can be increased by analysing and minimizing the residual stress and deflection error in virtual environments. [ABSTRACT FROM AUTHOR]

Background: Obesity nowadays becomes a major medical and social problem in the world. Obesity is a pandemic health problem recognized as a disease of time and is also an important cause of morbidity and mortality. The aim of this study was to investigate the persistent histopathologic changes after Helicobacter pylori (H. pylori) treatment in laparoscopic sleeve gastrectomy (LSG) specimens and correlation between high body mass index (BMI) and histopathological findings. Materials and Methods: Asymptomatic 520 patients were candidate for laparoscopic sleeve gastrectomy (2017-2019) who had not symptom of Helicobacter pylori infection, visually normal endoscopy and had positive H. pylori urease recently. They treated with triple regimen (clarithromycin, amoxicillin for 2 weeks and proton-pump inhibitor (PPI) for 2 month). Eradication was confirmed by urea breath test (UBT). After operation specimens were evaluated histopathologically. Results: Females were 58.3% of the patients. Mean BMI were 44.2 (females) and 46.3 (males). Normal LSG specimens were 58.3%. Most common abnormal histopathology findings were; chronic mild active and inactive gastritis (21.3%), chronic moderate active and inactive gastritis (16.0%), chronic severe active and inactive gastritis (3.3%), had not follicular gastritis, lymphoid aggregates (0.6 %), intestinal metaplasia (0.2%) and PPI effect (0.2%). Significant correlation was observed between the higher patients BMI (BMI>45) with abnormal histopathology findings specially moderate and severe degree of chronic active and inactive gastritis. Conclusion: Patients with higher BMI was at more risk for post H. pylori treatment abnormal pathology like chronic active gastritis which is the risk factor for atrophic gastritis may lead to preventable gastric cancer. Patients with higher BMI (=45) and H. pylori positive urease test with visually normal endoscopy, mainly candidate for the laparoscopic Roux-en-Y gastric bypass (LRYGB). Permanent endoscopic follow up in these patients are impossible, therefore, endoscopic random tissue mapping even after H. pylori treatment is appropriate. [ABSTRACT FROM AUTHOR]

Acute pancreatitis is characterized by activation of digestive enzymes inside the pancreas. In severe pancreatitis, necrosis of pancreas and surrounding tissues may occur. Acute necrotizing pancreatitis commonly presents as pancreatic abscess occasionally with systemic complications. Rarely, necrotic tissue may be drained from scrotum due to retroperitoneal extension of necrotic process. Here, we report a case of acute necrotizing pancreatitis in a 29-year-old man who presented with severe abdominal pain, nausea and vomiting. Acomputerized tomography (CT) scan confirmed necrotizing pancreatitis with multiple abscesses spreading bilaterally in the pelvic cavity. Several surgical operations were performed, including necrosectomy and drainage. Subsequently, the patient developed a scrotal abscess, which was drained surgically. The patient's condition was complicated by pleural effusion, acute respiratory distress syndrome, colocutaneous and scrotal fistulas, and incisional hernia. It seems that the scrotal abscess is a very rare complication of necrotizing pancreatitis. [ABSTRACT FROM AUTHOR]

Background: Ramadan fasting is a major challenge for exercising Muslims especially in warm seasons. There is some evidence to indicate that Ramadan fasting causes higher subjective ratings of perceived exertion (RPE) in fasting Muslims. The mechanisms of this phenomenon are not known exactly. The role of respiratory muscle strength in this regard has not been studied yet. Objectives: The aim of this study was investigation of the effects of Ramadan fasting on respiratory muscle strength. Patients and Methods: In a before-after study, from 35 fasting, apparently healthy, male adults who had fasted from the beginning of Ramadan, maximal inspiratory muscle pressure (MIP) and peak inspiratory flow (PIF) were measured in the last week of Ramadan month in summer. At the time of test, there was not any sleep problem in participants and all of them had good cooperation. Three months later, after exclusion of incompatible persons mainly because of change in their physical activity level, smoking behavior or drug consumption, the measurements were repeated in 12 individuals. Results: Weight, MIP and PIF data had normal distribution (Kolmogorov-Smirnov Test). There was a significant increase in MIP (mean 8.3 cm H2O with 95% confidence interval of 2.2 - 14.3) and PIF (mean 0.55 lit/s with 95% confidence interval of 0.02 - 1.07) and weight (mean 3.4 Kg with 95% confidence interval of 2.2 - 4.5) after Ramadan (Paired t test with P < 0.05).When weight difference was used as a covariate in repeated measure ANOVA test, there was no further significant difference between MIP and PIF measurements. Conclusions: Ramadan fasting may cause reduction of respiratory muscle strength through reduction of body weight. [ABSTRACT FROM AUTHOR]

Virtual manufacturing systems carry out the simulation of manufacturing processes in digital environment in order to increase accuracy as well as productivity in part production. There are different error sources in machine tools, such as tool deflection, geometrical deviations of moving axis, and thermal distortions of machine tool structures. The errors due to tool deflection are caused by cutting forces and have direct effects on dimensional accuracy, surface roughness of the parts, and efficient life of the cutting tool, holder, and spindle. This paper presents an application of virtual machining systems in order to improve the accuracy and productivity of part manufacturing by monitoring and minimizing the tool deflection error. The tool deflection error along machining paths is monitored to present a useful methodology in controlling the produced parts with regard to desired tolerances. Suitable tool and spindle can also be selected due to the ability of error monitoring. In order to minimize the error, optimization technique based on genetic algorithms is used to determine optimized machining parameters. Free-form profile of virtual and real machined parts with tool deflection error is compared in order to validate reliability as well as accuracy of the software. [ABSTRACT FROM AUTHOR]

Gossypiboma is defined as developing an exudative inflammatory process around retained foreign bodies (RFBs). This problem may be asymptomatic or present with severe systemic or regional symptoms. Traditionally, every RFB must be removed with a surgical procedure. In the era of minimally invasive surgery, laparoscopic removal is a good choice for these problems. A young woman was referred to us with intermittent vague abdominal pain and a history of open cholecystectomy. After initial imaging, we found a twisted string-like object in epigastrium. Considering clinical findings and imaging, the patient was taken to the operating room with a diagnosis of RFB. After an explorative laparoscopy, we found an encapsulated fibrotic mass around a surgical sponge with pus-like secretions. After diagnosing either RFB or gossypiboma, surgical intervention is mandatory, even in asymptomatic patients. Laparoscopy can help the surgeon to remove the retained item safely. Also, decreased length of stay and postoperative pain are significant advantages of laparoscopic removal. • A young woman presented to us complaining of vague abdominal pain without any specific signs and symptoms. • After initial imaging, a twisted string-like radiopaque object was seen in the epigastrium. • The patient was operated with the aid of laparoscopy, and the retained sponge removed successfully. [ABSTRACT FROM AUTHOR]

Background: The incidence of smuggling and illegal transport of substances by internal concealment, also known as body packing, is increasing. The clinical approach to body packers has changed significantly over the past two decades. In addition, the mortality of body packers is an important issue in patient management. The purpose of the current study is to determine the statistics and mortality related to body packing. Methods: In this cross-sectional study, all body packer patients who referred to Loghman Hakim hospital were evaluated from 2010 to 2017. Demographic characteristics, findings of clinical imaging, treatment, and outcome of the patients were recorded. The data were analyzed using SPSS version 21. Results: A total of 303 patients were enrolled in the study after the diagnosis of body packing by abdominal CT scanning without contrast. Conservative treatment including whole bowel irrigation (WBI) accompanied by close monitoring was done for 78% (n = 236) of patients; moreover, 26 patients (8.5%) underwent surgery after WBI, and 41 patients (13.5%) underwent surgery without bowel irrigation. Mortality was observed in eight patients (2.7%) five of whom (62.5%) died before surgery and had the clinical manifestation of crystal (methamphetamine) and cannabis toxicity. Furthermore, three patients (37.5%) died due to the complications of surgery such as gastrointestinal leakage of an abdominal abscess. Conclusion: Conservative treatment seems to be better for the management of body packers. In addition, it is necessary to monitor patients for possible signs and symptoms of intoxication and gastrointestinal obstruction. [ABSTRACT FROM AUTHOR]