Search

The article "Feasibility and Safety Outcomes after Reoperation on the Aortic Root: 20 Years Experience of a Single Center" published in the journal Thoracic & Cardiovascular Surgeon discusses the increasing number of reoperations on the aortic root due to improved safety of aortic surgery. The study analyzed 192 patients who underwent reoperation, with factors such as age over 60 years, dilatation at reoperation, bleeding complications, and combined procedures on the aortic root and arch being identified as risk factors for adverse outcomes. The findings suggest that mortality after reoperation is influenced by pre- and perioperative events, emphasizing the importance of careful management in these cases. [Extracted from the article]

The article "Age is a Significant Driver of Long-term Outcomes in Patients Receiving Aortic Arch Reoperations" published in the journal Thoracic & Cardiovascular Surgeon discusses the impact of age on the long-term outcomes of patients undergoing aortic arch reoperations. The study analyzed data from 108 patients who underwent reoperations on the aortic arch between 1999 and 2023, identifying age, history of coronary artery disease, and chronic kidney disease as preoperative risk factors for adverse outcomes. The study found that age over 57.5 years was a significant predictor of lower overall survival rates, emphasizing the importance of age as a key factor in patient outcomes. [Extracted from the article]

Wind energy is generated via the use of wind blades, turbines, and generators that are deployed over a given area. To achieve a higher energy and system reliability, the wind blade and other units of the system must be designed with suitable materials. In this paper, however, a computational intelligent model based on an artificial neutral network has been proposed for the evaluation of the reliability of the wind turbine blade designed with the FRP material. The simulation results show that there was a reduction in the training mean square error, testing (re–training) mean square error and validation mean square error, when the number of training epochs is increased by 50% such that the minimum mean square error and maximum mean square error were 0.0011 and 0.0061, respectively. The low validation mean square error in the simulation results implies that the developed artificial neural network has a good accuracy when determining the reliability and the failure probability of the wind turbine blade. [ABSTRACT FROM AUTHOR]

Explores the question "Why are so many stationary states allowed by traditional quantum mechanics not realized in nature?" through discussion of classical observables and superselection rules. Three examples are given that can be used in introductory courses (including the fermion/boson property and the mass of a "nonrelativistic" particle). (JN)

Harmonic confinement of initially isolated symmetric triatomic molecules can induce a transition from a bent, directed bond-type structure to helium-like angular correlation of the two equal particles. In an exactly solvable modification of the Hooke-Calogero model it is demonstrated that there is a well-defined transition between the two cases if the confinement strength is increased. Furthermore confinement is shown to reduce the system’s effective diameter, which at the transition point has shrunk by 26% in comparison to the isolated system. [ABSTRACT FROM AUTHOR]

Angular correlation in three-body systems varies between the limiting cases of slightly perturbed equi-distribution, as in the electronic ground state of helium and directed bond-type bent structure, as in the isolated water molecule. In an exactly solvable modification of the Hooke-Calogero model, it is shown that there is a sharp transition between the two cases if the particles’ masses are suitably varied. In the Hooke-Calogero model attraction between different particles is harmonic and the repulsion between equal particles is given by a 1/ r 2 potential. The bent structure appears in the angular distribution function if the masses of the two equal particles are below a critical value, which depends on the mass of the third particle. Above the critical value, the angular correlation is of helium type and exhibits a minimum at 0° corresponding to the Coulomb hole and a maximum at 180°. The model thus demonstrates the modulating role of mass in the transition between semi-rigid structure and more diffuse nuclear states. [ABSTRACT FROM AUTHOR]

Presents a study which looks at the persistence of organic compounds with global pollution potential on the basis of a minimal set of compound-specific parameters. Detailed information on the methodology used to conduct the study; Discussion surrounding the results of the study.

Focuses on the difficulties in determining effective global decay rates of chemical and organic pollutants. Importance of determining the half life of organic pollutants in ecological risk assessment; Derivation of the limiting law in natural systems; Mathematical proof of effective decay rate in real systems.

In order to determine the allergenic activity of five purified horse allergens, 22 children allergic to horses according to history, skin test, and leukocyte histamine release were evaluated. Washed leukocytes from all patients were tested for allergen-induced histamine release utilizing four epidermal horse allergens (Ags 6, 9, 11, and 15) and horse serum albumin. Crossed radioimmunoelectrophoresis was carried out with a standard horse dander extract and serum from each patient. The results showed considerable variation in the individual allergoprints. Ag 11 had the highest mean allergenic activity. Sensitivity to horse serum albumin was demonstrated three times. Our data show that the amount of serum IgE antibodies bound by horse allergens correlates significantly with the capacity of the allergens to induce histamine release from washed leukocytes. [ABSTRACT FROM AUTHOR]

This article illustrates a case of multiple penetrating atherosclerotic ulcers of the abdominal aorta and its treatment by endovascular stent graft placement. A 70 year old man with known Systemic hypertension and presented for diagnostic evaluation of suspected aortic dissection. Previous routine ultrasonography raised suspicion of abdominal aortic dissection in the asymptomatic patient. Endovascular stent graft placement may therefore provide a less invasive alternative to traditional surgery in the treatment of Penetrating atherosclerotic ulcers.