Meniscus position and size in knees with versus without structural knee osteoarthritis progression: data from the osteoarthritis initiative

Objective To explore whether and which quantitative 3D measures of medial and/or lateral meniscus position and size are associated with subsequent medial femorotibial structural progression of knee osteoarthritis and to determine the correlation between central slice and total meniscus measures. Materials and Methods Knees with radiographic osteoarthritis from Osteoarthritis Initiative participants with longitudinal medial MRI-based cartilage thickness and radiographic joint space width (JSW) loss over 12 months were selected. These 37 structural progressor knees (64.7 ± 8.0y, 30.2 ± 4.6 kg/m2, 35% men) were matched 1:1 to 37 non-progressor knees (64.6 ± 9.8y, 30.2 ± 4.4 kg/m2, 35% men) without cartilage thickness or JSW loss. Quantitative measures of meniscus position and size were computed from manual segmentations of coronal baseline MRIs. Cohen’s D was used as measure of effect size. Results Maximum extrusion distance of the total medial meniscus and mean extrusion in the central 5 and in the central slice were greater for progressor than non-progressor knees (Cohen’s D 0.58–0.66). No significant differences were observed for medial tibial coverage or mean extrusion (entire meniscus). Among medial meniscus morphology measures, only mean height differed between progressor vs non-progressor knees (Cohen’s D 0.40). Among lateral meniscus measures, height and volume were greater in progressor vs. non-progressor knees (Cohen’s D 0.46–0.83). Mean extrusion measures were highly correlated between the entire meniscus and the central (r = 0.88) or the central 5 (r = 0.93) slices. Conclusions 3D maximum and central medial meniscus extrusion may serve as predictors for subsequent structural progression. Central meniscus extrusion measures could substitute 3D extrusion measurement across the entire meniscus.

Deep Learning for Detection of Colonic Polyps from Computed Tomography Colonoscopy Images Combined with Colonoscopy

The objective of this study was to investigate the diagnosis of colonic polyps (CP) through the computed tomography (CT) images combined with colonoscopy based on Fourier central slice theorem algorithm. In this study, 86 patients with CP admitted to hospital were selected as research objects. CT imaging and colonoscopy were applied to diagnose the patients based on the algorithm of Fourier central slice theorem. The results showed that the diagnostic detection rates of CP and colon cancer (CC) were 88.2% and 94.2%, respectively. The occurrence site of CP was the sigmoid and ascending colon. 38 patients were positive for serosal invasion of CP while 42 patients were negative for serosal invasion of CP, and there were no statistical differences ( P > 0.05 ). The lesion positions of remaining 6 cases were hard to find and could not be detected accurately. Besides, the diagnostic accuracy of preoperative and postoperative stages III and IV was all 100.00%. The combination of CT imaging and colonoscopy was employed to diagnose CP, which was found to be able to accurately locate the lesions, to effectively evaluate the tumor stage before and after surgery, and to have a good diagnostic efficacy in detecting tumor serosal layer.

The HEPS project

The High Energy Photon Source (HEPS), a 6 GeV green-field diffraction-limited storage ring light source, will be built in Beijing, China. The HEPS design has been evolving for about ten years, and is now mostly finished and ready for construction. The storage ring is based on a modified hybrid seven-bend achromat (7BA) design, where bending magnets with reverse bending angles and longitudinal gradients are adopted to reach an ultralow natural emittance of 34.2 pm with a circumference of 1360.4 m. The central slice of the dipole in the middle of the modified hybrid 7BA, with flexible magnetic field, is used as the source of the bending-magnet beamline. Moreover, alternating high- and low-beta sections are specially designed to generate and deliver X-ray synchrotron radiation with high brightness of 5 × 1022 photons s−1 mm−2 mrad−2 (0.1% bandwidth)−1. Here, the HEPS storage ring design and solutions to the challenges inherent in this ultralow-emittance design are presented.

Effect of Silicon on the Cast Macrostructure of Fe-Si Alloys

ABSTRACTIn this work was studied the effect of silicon content from 0.5 to 3 wt.% Si on the macrostructure of casting ingots. Fe-Si alloys with low contents of impurities were produced in electric induction furnace under inert atmosphere. Castings of 12.5 cm thick, 25 cm long and 30 cm high were obtained of each alloy poured into metallic mould. The ingots obtained were sectioned in slices of 12 cm wide, 25 cm high and 2 cm thick, the central slice of each ingot was prepared metallographically to reveal the macrostructure of the six cast alloys. The results indicate that alloys with low silicon levels (0.5 and 1.0% Si) and with small solidification intervals have relatively fine equiaxed grains, while alloys with higher silicon content and a higher solidification intervals present predominantly columnar grains. These macrostructures are not the usually structures linked to short and long freezing range. Another important result is the absence of dendritic structure usually present in cast alloys.

Probing of the hot-band excitations in the photodissociation of OCS at 288 nm by DC slice imaging

The photodissociation dynamics of OCS at 288 nm has been investigated using the DC (direct current) slice imaging technique, which is a recently developed high-resolution "slicing" approach that directly measures the central slice of the photofragment distribution in imaging experiments. By analyzing a DC sliced image of S(1D2) photofragments we observe dissociation originating from OCS molecules excited up to v2 = 4 in the molecular beam. The measured translational energy distribution was used to determine the branching ratio for the contribution from each initial bending state (0 v2 0) of OCS and relative photodissociation cross section ratios compared to v2 = 1. Large negative anisotropy parameters determined as a function of the S(1D2) fragment recoil speed indicate that the photodissociation of OCS at 288 nm occurs exclusively from the 11A′′(1Σ–) bending excited potential surface that can be accessed through a perpendicular transition.Key words: DC slicing imaging, OCS, photodissociation, hot-band excitation.