36 research outputs found
On Fano schemes of complete intersections
We provide enumerative formulas for the degrees of varieties parameterizing
hypersurfaces and complete intersections which contain pro-jective subspaces
and conics. Besides, we find all cases where the Fano scheme of the general
complete intersection is irregular of dimension at least 2, and for the Fano
surfaces we deduce formulas for their holomorphic Euler characteristic.Comment: Added lacking references, corrected acknowledgments, minor editorial
change
Annealing study and thermal investigation on bismuth sulfide thin films prepared by chemical bath deposition in basic medium
This is a post-peer-review, pre-copyedit version of an article published in Applied Physics A 124.2 (2018): 166. The final authenticated version is available online at: http://doi.org/10.1007/s00339-018-1584-7Bismuth sulfide thin films were prepared by chemical bath deposition using thiourea as sulfide ion source in basic medium. First, the effects of both the deposition parameters on films growth as well as the annealing effect under argon and sulfur atmosphere on as-deposited thin films were studied. The parameters were found to be influential using the Doehlert matrix experimental design methodology. Ranges for a maximum surface mass of films (3 mg cm-2) were determined. A well crystallized major phase of bismuth sulfide with stoichiometric composition was achieved at 190°C for 3 hours. The prepared thin films were characterized using Grazing Incidence X-ray diffraction (GIXRD), Scanning Electron Microscopy (SEM) and Energy Dispersive X-ray analysis (EDX). Second, the band gap energy value was found to be 1.5 eV. Finally, the thermal properties have been studied for the first time by means of the electropyroelectric (EPE) technique. Indeed, the thermal conductivity varied in the range of 1.20 - 0.60 W m-1 K-1 while the thermal diffusivity values increased in terms of the annealing effect ranging from 1.8 to 3.5 10-7 m2s-1This work was financially
supported by the Tunisian Ministry of Higher Education and Scientific
Research and by the WINCOST (ENE2016-80788-C5-2-R) project
funded by the Spanish Ministry of Economy and Competitivenes
Assessing colonic anatomy normal values based on air contrast enemas in children younger than 6 years
Contrast enemas with barium or water-soluble contrast agents are sometimes performed in children with severe intractable constipation to identify anatomical abnormalities. However there are no clear definitions for normal colonic size or abnormalities such as colonic dilation or sigmoid redundancy in children. To describe characteristics of colonic anatomy on air contrast enemas in children without constipation to provide normal values for colonic size ratios in children. We performed a retrospective chart review of children aged 0-5 years who had undergone air contrast enemas for intussusception. The primary outcome measures were the ratios of the diameters and lengths of predetermined colonic segments (lengths of rectosigmoid and descending colon; diameters of rectum, sigmoid, descending colon, transverse colon and ascending colon) in relation to the L2 vertebral body width. We included 119 children (median age 2.0 years, range 0-5 years, 68% boys). Colonic segment length ratios did not change significantly with age, although the differences for the rectosigmoid/L2 ratio were borderline significant (P = 0.05). The ratios that involved the rectal and ascending colon diameters increased significantly with age, while diameter ratios involving the other colonic segments did not. Differences by gender and race were not significant. These data can be used for reference purposes in young children undergoing contrast studies of the colo
Assessing colonic anatomy normal values based on air contrast enemas in children younger than 6 years
Contrast enemas with barium or water-soluble contrast agents are sometimes performed in children with severe intractable constipation to identify anatomical abnormalities. However there are no clear definitions for normal colonic size or abnormalities such as colonic dilation or sigmoid redundancy in children. To describe characteristics of colonic anatomy on air contrast enemas in children without constipation to provide normal values for colonic size ratios in children. We performed a retrospective chart review of children aged 0-5 years who had undergone air contrast enemas for intussusception. The primary outcome measures were the ratios of the diameters and lengths of predetermined colonic segments (lengths of rectosigmoid and descending colon; diameters of rectum, sigmoid, descending colon, transverse colon and ascending colon) in relation to the L2 vertebral body width. We included 119 children (median age 2.0 years, range 0-5 years, 68% boys). Colonic segment length ratios did not change significantly with age, although the differences for the rectosigmoid/L2 ratio were borderline significant (P = 0.05). The ratios that involved the rectal and ascending colon diameters increased significantly with age, while diameter ratios involving the other colonic segments did not. Differences by gender and race were not significant. These data can be used for reference purposes in young children undergoing contrast studies of the colo