Efficient and accurate treatment of weak pairs in local CCSD(T) calculations. II. Beyond the ring approximation

2014 ◽  
Vol 140 (24) ◽  
pp. 244107 ◽  
Author(s):  
Martin Schütz ◽  
Oliver Masur ◽  
Denis Usvyat
2020 ◽  
Vol 34 ◽  
pp. 205873842094175
Author(s):  
Wenya Li ◽  
Feizhao Jiang ◽  
Xiaoxiao Li ◽  
Hong Li ◽  
Zhihai Zheng

Eosinophilic cholangiopathy is termed as a rare, benign, and self-limiting disease. Moreover, the interference of malignant tumor to diagnosis and the changing process of disease make the accurate treatment proposal challenging. A significant number of patients require surgery for the definitive diagnosis and resolution of symptoms. We put forward a case of eosinophilic cholangiopathy infiltrating the gallbladder and bile duct with bone marrow involved, coupled with peripheral eosinophilia. The patient underwent a successful treatment using laparoscopic cholecystectomy and steroids, instead of extrahepatic bile duct excision with Roux-en-Y hepaticojejunostomy. The patient gets an accurate treatment in a minimally invasive manner. In conclusion, surgery refers to not only a diagnostic methodology but also a treatment. When the bile duct and gallbladder are involved at the same time, and cannot distinguish benign and malignant diseases, laparoscopic cholecystectomy is feasible, the effect is the same, and the symptoms of eosinophilic cholecystitis are relieved.


2020 ◽  
Vol 7 (1) ◽  
Author(s):  
Miles L. Timpe ◽  
Maria Han Veiga ◽  
Mischa Knabenhans ◽  
Joachim Stadel ◽  
Stefano Marelli

AbstractIn the late stages of terrestrial planet formation, pairwise collisions between planetary-sized bodies act as the fundamental agent of planet growth. These collisions can lead to either growth or disruption of the bodies involved and are largely responsible for shaping the final characteristics of the planets. Despite their critical role in planet formation, an accurate treatment of collisions has yet to be realized. While semi-analytic methods have been proposed, they remain limited to a narrow set of post-impact properties and have only achieved relatively low accuracies. However, the rise of machine learning and access to increased computing power have enabled novel data-driven approaches. In this work, we show that data-driven emulation techniques are capable of classifying and predicting the outcome of collisions with high accuracy and are generalizable to any quantifiable post-impact quantity. In particular, we focus on the dataset requirements, training pipeline, and classification and regression performance for four distinct data-driven techniques from machine learning (ensemble methods and neural networks) and uncertainty quantification (Gaussian processes and polynomial chaos expansion). We compare these methods to existing analytic and semi-analytic methods. Such data-driven emulators are poised to replace the methods currently used in N-body simulations, while avoiding the cost of direct simulation. This work is based on a new set of 14,856 SPH simulations of pairwise collisions between rotating, differentiated bodies at all possible mutual orientations.


2011 ◽  
Vol 133 (5) ◽  
Author(s):  
F. P. P. Tan ◽  
N. B. Wood ◽  
G. Tabor ◽  
X. Y. Xu

In this study, two different turbulence methodologies are investigated to predict transitional flow in a 75% stenosed axisymmetric experimental arterial model and in a slightly modified version of the model with an eccentric stenosis. Large eddy simulation (LES) and Reynolds-averaged Navier–Stokes (RANS) methods were applied; in the LES simulations eddy viscosity subgrid-scale models were employed (basic and dynamic Smagorinsky) while the RANS method involved the correlation-based transitional version of the hybrid k-ε/k-ω flow model. The RANS simulations used 410,000 and 820,000 element meshes for the axisymmetric and eccentric stenoses, respectively, with y+ less than 2 viscous wall units for the boundary elements, while the LES used 1,200,000 elements with y+ less than 1. Implicit filtering was used for LES, giving an overlap between the resolved and modeled eddies, ensuring accurate treatment of near wall turbulence structures. Flow analysis was carried out in terms of vorticity and eddy viscosity magnitudes, velocity, and turbulence intensity profiles and the results were compared both with established experimental data and with available direct numerical simulations (DNSs) from the literature. The simulation results demonstrated that the dynamic Smagorinsky LES and RANS transitional model predicted fairly comparable velocity and turbulence intensity profiles with the experimental data, although the dynamic Smagorinsky model gave the best overall agreement. The present study demonstrated the power of LES methods, although they were computationally more costly, and added further evidence of the promise of the RANS transition model used here, previously tested in pulsatile flow on a similar model. Both dynamic Smagorinsky LES and the RANS model captured the complex transition phenomena under physiological Reynolds numbers in steady flow, including separation and reattachment. In this respect, LES with dynamic Smagorinsky appeared more successful than DNS in replicating the axisymmetric experimental results, although inflow conditions, which are subject to caveats, may have differed. For the eccentric stenosis, LES with Smagorinsky coefficient of 0.13 gave the closest agreement with DNS despite the known shortcomings of fixed coefficients. The relaminarization as the flow escaped the influence of the stenosis was amply demonstrated in the simulations, graphically so in the case of LES.


2013 ◽  
Vol 139 (16) ◽  
pp. 164116 ◽  
Author(s):  
Oliver Masur ◽  
Denis Usvyat ◽  
Martin Schütz
Keyword(s):  

Symmetry ◽  
2021 ◽  
Vol 13 (3) ◽  
pp. 516
Author(s):  
Simone Taioli ◽  
Stefano Simonucci

In this work, we outline a general method for calculating Auger spectra in molecules, which accounts for the underlying symmetry of the system. This theory starts from Fano’s formulation of the interaction between discrete and continuum states, and it generalizes this formalism to deal with the simultaneous presence of several intermediate quasi-bound states and several non-interacting decay channels. Our theoretical description is specifically tailored to resonant autoionization and Auger processes, and it explicitly includes the incoming wave boundary conditions for the continuum states and an accurate treatment of the Coulomb repulsion. This approach is implemented and applied to the calculation of the K−LL Auger and autoionization spectra of ozone, which is a C2v symmetric molecule, whose importance in our atmosphere to filter out radiation has been widely confirmed. We also show the effect that the molecular point group and, in particular, the localization of the core-hole in the oxygen atoms related by symmetry operations, has on the electronic structure of the Auger states and on the spectral lineshape by comparing our results with the experimental data.


1993 ◽  
Vol 560 (1) ◽  
pp. 518-540 ◽  
Author(s):  
Christoph Bedau ◽  
Friedrich Beck

2021 ◽  
Vol 15 (6) ◽  
pp. e0009541
Author(s):  
Georgina Meza-Radilla ◽  
Violeta Larios-Serrato ◽  
Rigoberto Hernández-Castro ◽  
J. Antonio Ibarra ◽  
Paulina Estrada-de los Santos

Background Burkholderia sensu stricto is comprised mainly of opportunistic pathogens. This group is widely distributed in the environment but is especially important in clinical settings. In Mexico, few species have been correctly identified among patients, most often B. cepacia is described. Methodology/Principal findings In this study, approximately 90 strains identified as B. cepacia with the VITEK2 system were isolated from two medical centers in Mexico City and analyzed by MLSA, BOX-PCR and genome analysis. The initial identification of B. cepacia was confirmed for many strains, but B. contaminans, B. multivorans and B. vietnamiensis were also identified among clinical strains for the first time in hospitals in Mexico. Additionally, the presence of B. pseudomallei was confirmed, and a novel species within the B. cepacia complex was documented. Several strains misidentified as B. cepacia actually belong to the genera Pseudomonas, Stenotrophomonas and Providencia. Conclusions/Significance The presence of different Burkholderia species in Mexico was confirmed. Correct identification of Burkholderia species is important to provide accurate treatment for immunosuppressed patients.


2017 ◽  
Vol 1 (4) ◽  
pp. 98-99
Author(s):  
Zahra Mazloum khorasani ◽  
Mahmood Tara ◽  
Kobra Etminani ◽  
Zohre Moosavi ◽  
Zahra Ebnehoseini

Introduction: Diabetes is the most common endocrine disease. Given the importance of medical record documentation for diabetic patients and its significant impact on accurate treatment process, as well as early diagnosis and treatment of acute and chronic complications, this study aimed to qualitatively evaluate medical record documentation of diabetic patients. Methods: This descriptive and cross-sectional study was conducted on all medical records of diabetic patients (1200 cases) in the comprehensive Diabetes Center of Imam Reza Hospital. A checklist was prepared according to the main sectors and their sub-data elements to conduct a qualitative evaluation on documentation of medical records of diabetic patients.  Descriptive statistics were used to report the results. Results: In this study, 1200 (710 women and 490 men) cases were evaluated. Mean documentation of main sectors of diabetic patients’ records were as follows: 49% demographic characteristics, 14% patient referral, 4% diagnosis, 50% lab tests, 25% diabetes medications,13% nephropathy screening test, 10% diabetic neuropathy, 41% specialty and subspecialty consultations and internal medicine physicians visits did not complete for all the patients. Conclusion: According to the results of this study, qualitative evaluation of medical record documentation of diabetic patients Showed poor documentation in this regard. It is suggested that results of this study be accessible to physicians of healthcare centers to take a positive step toward improved documentation of medical records. In addition, it seems necessary to modify diabetic medical records.


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