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In this study, the Open Vehicle Routing Problem, which the companies widely employ in practice using third‐party logistics services, is discussed. This problem is in the class of high‐dimensional and complex optimization problems. A three‐phase Variable Neighborhood Search Algorithm was proposed to solve large‐scale problems efficiently. In this proposed method, eight different neighborhoods are used, four within the route and four between the routes. In addition to this, wise shaking strategies are designed to escape local optimal solutions. The method's performance was tested on literature test instances and comparatively reported its competitiveness. [ABSTRACT FROM AUTHOR]

In this paper, two new approaches are proposed for extracting composite priority rules for scheduling problems. The suggested approaches use simulation and gene expression programming and are able to evolve specific priority rules for all dynamic scheduling problems in accordance with their features. The methods are based on the idea that both the proper design of the function and terminal sets and the structure of the gene expression programming approach significantly affect the results. In the first proposed approach, modified and operational features of the scheduling environment are added to the terminal set, and a multigenic system is used, whereas in the second approach, priority rules are used as automatically defined functions, which are combined with the cellular system for gene expression programming. A comparison shows that the second approach generates better results than the first; however, all of the extracted rules yield better results than the rules from the literature, especially for the defined multi-objective function consisting of makespan, mean lateness and mean flow time. The presented methods and the generated priority rules are robust and can be applied to all real and large-scale dynamic scheduling problems. [ABSTRACT FROM AUTHOR]

Background: Previous studies have evaluated the presence of juxtapapillary duodenal diverticula (JPDD) and the association with pancreatobiliary disease, but not the association of the papilla with an existing JPDD. We investigated the association of different localizations of the papilla with JPDD. Methods: We studied patients in whom JPDD was detected during endoscopic retrograde cholangiopancreatography. Patients were classified into 3 groups: 1) papilla located inside the diverticulum, 2) papilla located at the edge of the diverticulum and 3) papilla located closer than 3 cm to the diverticulum. The patients were examined with respect to localization of papilla--diverticula and to the association of the localization with pancreaticobiliary disease. Results: We enrolled 274 patients in our study. Biliary stone disease more frequently existed in group 3. The number of patients presenting with obstructive jaundice was higher in groups 2 (83.6%) and 3 (83.3%) than group 1 (66%). Cholangitis was more common in group 1 (21.3%) than in groups 2 (6.7%) and 3 (2.3%). The presence of biliary stone disease among patients presenting with pancreatitis was significantly different between groups 1 and 3 (p = 0.013) and between groups 2 and 3 (p = 0.017). The common bile duct more frequently contained stones or sludge in group 3 than in groups 1 and 2. Conclusion: When the papilla is located close to the JPDD, the incidence of biliary stone disease decreases, and pancreatobiliary diseases are caused mostly in the absence of biliary stone disease. Contexte : Des etudes anterieures ont evalue la presence de diverticules duodenaux juxtapapillaires (DDJP) et leur lien avec la maladie pancreatobiliaire, mais n'ont pas analyse le lien entre la papille et les DDJP existants. Nous avons analyse le lien entre diverses localisations de la papille et les DDJP. Methodes : Nous avons etudie des patients chez qui des DDJP ont ete detectes lors d'une cholangiopancreatographie endoscopique retrograde. Les patients ont ete classes en 3 groupes : 1) papille a l'interieur du diverticule, 2) papille a l'extremite du diverticule et 3) papille a moins de 3 cm du diverticule. L'examen a donc porte sur la localisation de la papille par rapport aux diverticules et sur le lien entre sa localisation et la maladie pancreatobiliaire. Resultats : Nous avons inscrit 274 patients a notre etude. La cholelithiase s'observait davantage dans le groupe 3. Le nombre de patients souffrant d'ictere obstructif etait plus eleve dans les groupes 2 (83,6 %) et 3 (83,3 %) que dans le groupe 1 (66 %). La cholangite etait plus frequente dans le groupe 1 (21,3 %) que dans les groupes 2 (6,7 %) et 3 (2,3 %). Le taux de cholelithiase chez les patients souffrant de pancreatite etait significativement different entre les groupes 1 et 3 (p = 0,013) et entre les groupes 2 et 3 (p = 0,017). Il y avait plus de calculs ou de boue biliaires dans le canal choledoque des patients du groupe 3 que dans ceux des groupes 1 et 2. Conclusion : Lorsque la papille est situee pres des DDJP, l'incidence de la cholelithiase diminue, et les maladies pancreatobiliaires sont pour la plupart causees en l'absence de cholelithiase., Duodenal diverticula (DD) are classified as primary (true) or secondary (false) diverticula. Primary diverticula are mostly solitary and can be observed in the second part of the duodenum, in the [...]

Alveolar echinococcosis is a life-threatening zoonotic disease caused by Echinococcus multilocularis. The disease usually primarily involves the liver and shows tumor-like growth. Early diagnosis of alveolar echinococcosis is difficult because the disease is usually asymptomatic in the early stages. Untreated cases are fatal and result in death within 10 years of liver involvement. In the diagnosis of alveolar echinococcosis, the patient's medical history, radiological imaging findings, and serological and histopathological tests are used together. Radiological imaging methods are very important for early diagnosis and differential diagnosis of the disease. In this article, we wanted to review the diagnosis and treatment of alveolar echinococcosis and emphasize the importance of keeping it in mind, especially in cystic lesions of the liver, and the importance of early diagnosis of the disease. [ABSTRACT FROM AUTHOR]

Background: The majority of the diaphragmatic hernias developing on the right side are hernias developing after right hepatectomy. We aimed to present the clinical presentation at the time of admission, surgical treatment, and postoperative course of patients that developed DH following a major liver resection in our center. Patients and Methods: Liver surgeries performed in Ataturk University Organ Transplant Center and Ataturk University Research Hospital General surgery Hepatopancreatobiliary ward between 2012 and 2021 were analysed retrospectively. Demographic information, admission types (emergency or elective), admission clinics, the process of diaphragmatic hernia formation following hepatectomy, imaging methods used for diagnosis, and surgical methods performed were recorded for the patients with diaphragmatic hernia. Qualitative values were tabulated and their percentages were calculated. Results: Six hundred and sixty patients who underwent major liver surgery in our center between 2012 and 2021 were analysed. It was found that diaphragmatic hernia developed in 9 (1.4%) of those patients. The incidence of diaphragmatic hernia after donor hepatectomy was 3.04% in our study. The mean time from the first surgery until the DH diagnosis was 47.33 ± 38.16 months. 1 (11.1%) patient had small intestine perforation and 1 patient had both small intestine and colon perforation. One patient died before to the surgery. Conclusion: DH following liver resection can cause fatal complications and it should be intervened when diagnosed. Although it is rare, centers particularly focusing on hepatobiliary surgery should determine a follow‐up protocol to detect DH that develops after major liver resections. [ABSTRACT FROM AUTHOR]

In this study, it was aimed to investigate the general distribution and characteristics of hydatid cyst (HC) cases in society by a single-center comprehensive study. Three thousand ninety consecutive patients who were followed up and treated for HC in our hospital between January 2001 and December 2020 were analyzed retrospectively. It was determined that HC was seen more in males than females (54.84% and 45.16%, respectively) in childhood and more in females than males in adulthood (59.89% and 40.11%, respectively, P < 0.001). Regarding the living areas, 82.01% of the cases were living in the rural area and 17.99% in the city center (P < 0.001). It was observed that the cases increased significantly in the second ten years (72.36%) compared to the first 10 years (27.64%) (P < 0.001). At least one of the liver or lungs was involved in 95.08% of the cases. The liver was involved in 80.23% of the cases (66.87% in children, 84.94% in adults, P < 0.001) and the lung in 22.91% (38.59% in children, 17.38% in adults, P < 0.001). Other regions' involvement percentages were as follows: spleen 2.36%, musculoskeletal system 1.59%, kidneys 1.13%, intracranial region 0.91% (2.61% in children, 0.31% in adults, P < 0.001), omentum 0.91%, mediastinum 0.61%, cardiac region 0.58%, pelvic cavity 0.58%, diaphragm 0.55%, pancreas 0.13%, retroperitoneal area 0.13%, ovarian region 0.13%, uterine wall 0.06%, thyroid glands 0.03%, and nasal cavity 0.03%. HC ratio has increased in recent years. Liver involvement is more common in adults than children. Lung and intracranial involvement are more common in children than in adults. [ABSTRACT FROM AUTHOR]

Background/Aims: Liver transplant is the ultimate and exclusive treatment of liver failure. Since the transfer of hepatic lobe takes place along with its own hepatic artery, the anastomosis process requires the utilization of microsurgical techniques and equipment in the living donor liver transplantations (LDLT). The success of the anastomosis directly affects the result of the surgery and thereby effects patient survival. Otherwise, in the case of failure, it can lead to mortality of the patient. The aim of this study is to retrospectively evaluate the hepatic artery anastomosis in terms of vascular characteristics, arterial diameters, operation time, complications, and thrombosis rates and also to achieve more successful results with lower complication rates. Furthermore, the study aims to share the accumulated knowledge and the experience to develop the technique further and to learn how to make the transfer more easily in the future. Materials and Methods: From 2010 to 2017, 85 LDLTs were performed in Ataturk University Organ Transplantation and Research Center. The hepatic artery anastomosis was performed by the same microsurgeon. Results: We have not encountered any hepatic arterial thrombosis. The success of 100% anastomosis in our series is compatible with the literature, and it was found to have a higher success rate. However, the fact that our current series is small should not be overlooked. Conclusion: The collaboration between microsurgeons and transplant surgeons to reduce technical complications can play an important role in obtaining long-term and permanent transplantation outcomes. [ABSTRACT FROM AUTHOR]

Dispatching rules are among the most widely applied and practical methods for solving dynamic flexible job shop scheduling problems in manufacturing systems. Hence, the design of applicable and effective rules is always an important subject in the scheduling literature. The aim of this study is to propose a practical approach for extracting efficient rules for a more general type of dynamic job shop scheduling problem in which jobs arrive at the shop at different times and machine breakdowns occur stochastically. Limited-buffer conditions are also considered, increasing the problem complexity. Benchmarks are selected from the literature, with some modifications. Gene expression programming combined with a simulation model is used for the design of scheduling policies. The extracted rules are compared with several classic dispatching rules from the literature based on a multi-objective function. The new rules are found to be superior to the classic ones. They are robust and can be used for similar complex scheduling problems. The results prove the efficiency of gene expression programming as a nature-inspired method for dispatching rule extraction. [ABSTRACT FROM AUTHOR]