Yang-Baxter maps and symmetries of integrable equations on quad-graphs

A connection between the Yang-Baxter relation for maps and the multi-dimensional consistency property of integrable equations on quad-graphs is investigated. The approach is based on the symmetry analysis of the corresponding equations. It is shown that the Yang-Baxter variables can be chosen as invariants of the multi-parameter symmetry groups of the equations. We use the classification results by Adler, Bobenko and Suris to demonstrate this method. Some new examples of Yang-Baxter maps are derived in this way from multi-field integrable equations.Comment: 20 pages, 5 figure

Yang-Baxter maps and multi-field integrable lattice equations

A variety of Yang-Baxter maps are obtained from integrable multi-field equations on quad-graphs. A systematic framework for investigating this connection relies on the symmetry groups of the equations. The method is applied to lattice equations introduced by Adler and Yamilov and which are related to the nonlinear superposition formulae for the B\"acklund transformations of the nonlinear Schr\"odinger system and specific ferromagnetic models.Comment: 16 pages, 4 figures, corrected versio

Adaptive performance optimization for large-scale traffic control systems

In this paper, we study the problem of optimizing (fine-tuning) the design parameters of large-scale traffic control systems that are composed of distinct and mutually interacting modules. This problem usually requires a considerable amount of human effort and time to devote to the successful deployment and operation of traffic control systems due to the lack of an automated well-established systematic approach. We investigate the adaptive fine-tuning algorithm for determining the set of design parameters of two distinct mutually interacting modules of the traffic-responsive urban control (TUC) strategy, i.e., split and cycle, for the large-scale urban road network of the city of Chania, Greece. Simulation results are presented, demonstrating that the network performance in terms of the daily mean speed, which is attained by the proposed adaptive optimization methodology, is significantly better than the original TUC system in the case in which the aforementioned design parameters are manually fine-tuned to virtual perfection by the system operators

Three-Dimensional Tibiofemoral Kinematics of the Anterior Cruciate Ligament-Deficient and Reconstructed Knee during Walking

Background: It is possible that gait abnormalities may play a role in the pathogenesis of meniscal or chondral injury as well as osteoarthritis of the knee in patients with anterior cruciate ligament deficiency. Hypothesis: The three-dimensional kinematics of anterior cruciate ligament-deficient knees are changed even during low-stress activities, such as walking, but can be restored by reconstruction. Study Design: Case control study. Methods: Using a three-dimensional optoelectronic gait analysis system, we examined 13 patients with anterior cruciate ligament-deficient knees, 21 patients with anterior cruciate ligament-reconstructed knees, and 10 control subjects with uninjured knees during walking. Results: Normal patterns of knee flexion-extension, abduction-adduction, and internal-external rotation during the gait cycle were maintained by all subjects. A significant difference in tibial rotation angle during the initial swing phase was found in anterior cruciate ligament-deficient knees compared with reconstructed and control knees. The patients with anterior cruciate ligament-deficient knees rotated the tibia internally during the initial swing phase, whereas the others rotated externally. Conclusions: Patients with anterior cruciate ligament-deficient knees experienced repeated episodes of rotational instability during walking, whereas patients with reconstruction experienced tibial rotation that is closer to normal. Clinical Relevance: Repeated episodes of knee rotational instability may play a role in the development of pathologic knee conditions

Hydatid Disease of the Liver. Diagnosis and Surgical Treatment

A series of 155 cases of hepatic hydatid disease, occurring in 121 patients, were operated on at the Naval and Veterans Hospital of Athens. Ultrasonography and computerized axial tomography provided the preoperative diagnosis in 89 and 93 percent of the cases respectively in recent years. Thirty one percent of the cases presented with complications, the commonest of these being infection of the cyst (10 percent) and rupture of the cyst into the bile ducts (17 percent). Total cystectomy was performed in three cases and removal of the endocyst with its content in the remaining 152. The remaining cavity was either externally drained (57 cases), or filled with omentum (omentoplasty — 95 cases). External fistula and infection of the residual cavity occurred in 32 and 56 percent after simple drainage and in 4 and 2 percent respectively after omentoplasty. Differences are statistically significant (p < 0.001). Hospitalization was also significantly longer after drainage than after omentoplasty (p < 0.01). Obstructive jaundice after intrabiliary rupture of the cyst was more successfully managed after additional choledochoduodenostomy than after simple drainage of the common bile duct. Intrapericoneal recurrence of hydatid disease occurred in two cases. The conclusion of the present study is, that ultrasonography and computerized axial tomography provide an acceptable rate in the diagnosis and that omentoplasty offers a very low complication rate in the management of hydatid cystic disease of the liver

Evaluating Biological Risks in Biomedical Laboratories of Primary Health Care

Biomedical laboratories in primary health care centers play a critical role in disease detection, diagnosis, and management. However, the handling of diagnostic samples presents significant biological risks, particularly when biosafety measures are insufficient. This study focuses on analyzing the biological risks in 35 BSL-2 biomedical laboratories within health facilities in Athens, Greece, by examining compliance with biosafety regulations, personnel safety awareness, and biorisk management practices. A cross-sectional survey was conducted combining a customized checklist and a structured health and safety questionnaire, both developed based on the existing literature, including the international biosafety guidelines (BMBL 6th ed., WHO Biosafety Program Management, 2020). On-site evaluations were performed by a certified biorisk management advisor, and 158 laboratory professionals anonymously completed questionnaires on biosafety practices. The collected data were analyzed qualitatively, and where possible, quantitatively, by using SPSS software and p-values from the McNemar test. The results revealed widespread deficiencies in biosafety culture and risk management. Key gaps were identified in all layers of engineering controls, administrative controls, personal protective equipment (PPE), and emergency preparedness. Many laboratories failed to meet international biosafety standards set by organizations such as the WHO, CDC, and ECDC, as well as Greek legislation, highlighting the need for urgent improvements. To address these issues and mitigate the observed gaps, the implementation of comprehensive Biorisk Management Systems, enhanced biosafety training, and stricter enforcement of national and European biosafety regulations is strongly recommended. These measures are essential to protect laboratory personnel, the surrounding community, and the environment from lab-acquired infections and other biological threats

Evaluating Biological Risks in Biomedical Laboratories of Primary Health Care

Biomedical laboratories within primary health care centers are vital for the detection, diagnosis, and management of diseases. However, handling diagnostic samples poses significant biological risks, particularly when biosafety measures are insufficient. This study focuses on analyzing the biological risks in 35 BSL-2 biomedical laboratories situated in health facilities across Athens, Greece, by examining compliance with biosafety regulations, awareness of personnel safety, and practices related to biorisk management. A cross-sectional survey was conducted by combining a customized checklist and a structured health and safety questionnaire, both have been created from the existing literature including the international biosafety guidelines (BMBL 6th ed., WHO Biosafety Program Management, 2020). An expert biorisk management advisor performed on-site evaluations, while 158 laboratory staff members filled out anonymous questionnaires concerning biosafety practices. Findings indicate widespread deficiencies in biosafety culture and risk management. Key gaps were identified in engineering controls (such as restricted access and safety equipment), administrative controls (including risk assessments, standard operating procedures, biosafety manuals, biosafety officers, and ongoing training), personal protective equipment (PPE policies), and emergency preparedness (such as incident reporting, response plans, and occupational health services). Many laboratories failed to meet international biosafety standards set by the WHO, CDC, and ECDC, highlighting the need for urgent improvements. To mitigate these risks, the study recommends the adoption of comprehensive Biorisk Management Systems, enhanced biosafety training, and stricter enforcement of national and European biosafety regulations. Strengthening these measures is essential to protect the laboratory staff, the surrounding community, and the environment from potential biological threats and lab-acquired infections

Evaluating Biological Risks in Biomedical Laboratories of Primary Health Care

Biomedical laboratories within primary health care centers are vital for the detection, diagnosis, and management of diseases. However, handling diagnostic samples poses significant biological risks, particularly when biosafety measures are insufficient. This study focuses on analyzing the biological risks in 35 BSL-2 biomedical laboratories situated in health facilities across Athens, Greece, by examining compliance with biosafety regulations, awareness of personnel safety, and practices related to biorisk management. A cross-sectional survey was conducted by combining a customized checklist and a structured health and safety questionnaire, both have been created from the existing literature including the international biosafety guidelines (BMBL 6th ed., WHO Biosafety Program Management, 2020). An expert biorisk management advisor performed on-site evaluations, while 158 laboratory staff members filled out anonymous questionnaires concerning biosafety practices. Findings indicate widespread deficiencies in biosafety culture and risk management. Key gaps were identified in engineering controls (such as restricted access and safety equipment), administrative controls (including risk assessments, standard operating procedures, biosafety manuals, biosafety officers, and ongoing training), personal protective equipment (PPE policies), and emergency preparedness (such as incident reporting, response plans, and occupational health services). Many laboratories failed to meet international biosafety standards set by the WHO, CDC, and ECDC, highlighting the need for urgent improvements. To mitigate these risks, the study recommends the adoption of comprehensive Biorisk Management Systems, enhanced biosafety training, and stricter enforcement of national and European biosafety regulations. Strengthening these measures is essential to protect the laboratory staff, the surrounding community, and the environment from potential biological threats and lab-acquired infections