Application of Y-Z deformable magnetic ring for recanalization of transanal single-access rectal stricture.

Magnetic compression anastomosis has been reported to have remarkable clinical outcomes. Here, we tested the applicability of a Y-Z deformable magnetic ring (DMR) for non-surgical manipulation of rectal stenosis (RS) in a beagle dog model under a transanal single-access condition. RS was modeled in 8 beagle dogs using partial ligation with silk thread. Under X-ray guidance, the Y-Z DMR was positioned at the proximal and distal ends of the RS, and the magnetic ring was bent into an "O" shape, such that the two rings were magnetically attracted. Operation time, complications during or after operation, and discharge time of the magnetic rings were recorded. The anastomosis bursting pressure was measured two weeks after removing the rings, and its formation was assessed through gross and histological examination. Partial ligation with a silk thread successfully established the canine RS model. After Y-Z DMR installation, the magnetic ring was successfully reconfigured from an "S" to an "O" shape. Strong attraction existed between the rings. The operation time was 9-15 min (average: 11.75 ± 1.98 min). No rectal bleeding or perforation occurred during or after operation. The ring was naturally expelled 7-10 days after surgery. A pressure of > 300 mmHg was recorded at the point of anastomosis rupture. The rectal anastomosis appeared to have healed properly on the surface, which was confirmed histologically, signifying the success of this procedure. A Y-Z DMR facilitated the successful recanalization of transanal single-channel RS without needing surgery in an animal model.

EM and SAGE Algorithms for DOA Estimation in the Presence of Unknown Uniform Noise.

The existing expectation maximization (EM) and space-alternating generalized EM (SAGE) algorithms are only applied to direction of arrival (DOA) estimation in known noise. In this paper, the two algorithms are designed for DOA estimation in unknown uniform noise. Both the deterministic and random signal models are considered. In addition, a new modified EM (MEM) algorithm applicable to the noise assumption is also proposed. Next, these EM-type algorithms are improved to ensure the stability when the powers of sources are not equal. After being improved, simulation results illustrate that the EM algorithm has similar convergence with the MEM algorithm, the SAGE algorithm outperforms the EM and MEM algorithms for the deterministic signal model, and the SAGE algorithm cannot always outperform the EM and MEM algorithms for the random signal model. Furthermore, simulation results show that processing the same snapshots from the random signal model, the SAGE algorithm for the deterministic signal model can require the fewest computations.

Ab initio potential energy surface and bound states of the Xe-CO complex.

The first two-dimensional potential energy surface for the Xe-CO van der Waals interaction is calculated by the single and double excitation coupled-cluster theory with noniterative treatment of triple excitations. Mixed basis sets, aug-cc-pVQZ for the C and O atoms, and aug-cc-pVQZ-PP for the Xe atom, with an additional (3s3p2d2f1g) set of midbond functions, are used. Our potential energy surface has a single, nearly T-shaped minimum of -131.87 cm(-1) at R(e)=7.80a(0) and theta(e)=102.5 degrees. Based on the potential, the bound state energies are calculated for seven isotopomers of the Xe-(12)C(16)O complex, seven isotopomers of the Xe-(13)C(16)O complex, and three isotopomers of the Xe-(13)C(18)O complex. Compared with available experimental data, the predicted transition frequencies and spectroscopic constants are in good agreement with the experimental results.

Interaction of CO with Kr: Potential energy surface and bound states.

The first ab initio potential energy surface of the Kr-CO complex is developed using single and double excitation coupled-cluster theory with noniterative treatment of triple excitations. Mixed basis sets, aug-cc-pVQZ for the C and O atoms and aug-cc-pVQZ-PP for the Kr atom, with an additional (3s3p2d2f1g) set of midbond functions are used. The computed interaction energies in 336 configurations are analytically fitted to a two-dimensional potential model by a least squares fit. The potential has a minimum of -119.68 cm(-1) with Re=7.35a 0 at an approximate T-shaped geometry (theta e=98.5 degrees ). Bound state energies are calculated up to J=12, thus enabling a comprehensive comparison between theory and available experimental data as well as providing detailed guidance for future spectroscopic investigations of higher-lying states. The predicted transition frequencies and spectroscopic constants are in good agreement with the experimental results.