4,072 research outputs found
Chemical Constraints on the Water and Total Oxygen Abundances in the Deep Atmosphere of Saturn
Thermochemical equilibrium and kinetic calculations for the trace gases CO,
PH3, and SiH4 give three independent constraints on the water and total oxygen
abundances of Saturn's deep atmosphere. A lower limit to the water abundance of
H2O/H2 > 1.7 x 10^-3 is given by CO chemistry while an upper limit of H2O/H2 <
5.5 x 10^-3 is given by PH3 chemistry. A combination of the CO and PH3
constraints indicates a water enrichment on Saturn of 1.9 to 6.1 times the
solar system abundance (H2O/H2 = 8.96 x 10^-4). The total oxygen abundance must
be at least 1.7 times the solar system abundance (O/H2 = 1.16 x 10^-3) in order
for the SiH4 to remain below a detection limit of SiH4/H2 < 2 x 10^-10. A
combination of the CO, PH3, and SiH4 constraints suggests that the total oxygen
abundance on Saturn is 3.2 to 6.4 times the solar system abundance. Our results
indicate that oxygen on Saturn is less enriched than other heavy elements (such
as C and P) relative to a solar system composition. This work was supported by
NASA NAG5-11958.Comment: 19 pages, 2 figures, accepted for publication in the Astrophysical
Journa
Métabolisme de l'iode chez l'enfant et l'adolescent dans une région de la communauté. EUR 4964. = Iodine metabolism in children and adolescents in a region of the community. EUR 4964.
Local host response following an intramammary challenge with Staphylococcus fleurettii and different strains of Staphylococcus chromogenes in dairy heifers
Coagulase-negative staphylococci (CNS) are a common cause of subclinical mastitis in dairy cattle. The CNS inhabit various ecological habitats, ranging between the environment and the host. In order to obtain a better insight into the host response, an experimental infection was carried out in eight healthy heifers in mid-lactation with three different CNS strains: a Staphylococcus fleurettii strain originating from sawdust bedding, an intramammary Staphylococcus chromogenes strain originating from a persistent intramammary infection (S. chromogenes IM) and a S. chromogenes strain isolated from a heifer's teat apex (S. chromogenes TA). Each heifer was inoculated in the mammary gland with 1.0 x 10(6) colony forming units of each bacterial strain (one strain per udder quarter), whereas the remaining quarter was infused with phosphate-buffered saline. Overall, the CNS evoked a mild local host response. The somatic cell count increased in all S. fleurettii-inoculated quarters, although the strain was eliminated within 12 h. The two S. chromogenes strains were shed in larger numbers for a longer period. Bacterial and somatic cell counts, as well as neutrophil responses, were higher after inoculation with S. chromogenes IM than with S. chromogenes TA. In conclusion, these results suggest that S. chromogenes might be better adapted to the mammary gland than S. fleurettii. Furthermore, not all S. chromogenes strains induce the same local host response
Interobserver and intraobserver variability in the radiological assessment of sialolithiasis using cone beam computed tomography
BACKGROUND: Data regarding the inter- and intraobserver variability in the radiological assessment of sialolithiasis using cone beam computed tomography are missing in the current literature. This study assessed the inter- and intraobserver variability in the radiological assessment of sialolithiasis using cone beam computed tomography (CBCT). MATERIAL AND METHODS: In 107 patients, 130 salivary glands (65 parotid and 65 submandibular) with clinical signs of obstruction were assessed by four independent observers; 2 residents OMFS and 2 experienced OMFS. The observers analyzed the CBCT images and determined the absence or presence of one or more salivary stones in the affected gland. This procedure was repeated after three months. RESULTS: Interobserver agreements showed kappa values of 0.84 for the parotid gland, and 0.93 for the submandibular gland. Intraobserver agreements for the whole group reported kappa values between 0.83 - 0.95. There was no significant difference between residents and experienced OMFS. CONCLUSIONS: Due to the good inter- and intraobserver agreement, CBCT appears to be a reproducible imaging modality for detecting salivary stones in patients with signs and symptoms of obstructed parotid and submandibular glands. Key words:Salivary gland calculi, cone-beam computed tomography, observer variation
Guided placement of zygomatic implants in head and neck cancer patients:implant survival and patient outcomes at 1-3 years of follow-up
Zygomatic implants (ZI) are a valuable option for supporting an obturator prosthesis after maxillary resection. This study was performed to assess the clinical outcomes of a digitally validated guided technique for ZI placement, followed by immediate prosthetic obturation. The primary objective was to evaluate implant survival, while the secondary objective was to assess patient-reported quality of life post-rehabilitation. Twelve patients treated for head and neck cancer received a total of 36 ZI after ablative surgery. The mean duration of ZI follow-up was 30.1 months. The survival rate of ZI placed in non-irradiated patients was 100%, while it was 85% in irradiated patients. Patient-reported outcomes were evaluated using the Liverpool Oral Rehabilitation Questionnaire (LORQv3) and the University of Washington Quality of Life Questionnaire (UW-QOL v4). Most patients reported satisfactory outcomes in the oral function domain of the LORQv3 (mean score 17.7 ± 4.5; possible range 12-48, with lower scores indicating better outcomes). Regarding the UW-QOL v4, the swallowing and chewing domains had the highest scores (mean 97.5 ± 8.7 and 95.8 ± 14.4, respectively; maximum possible score of 100). In conclusion, this treatment approach improves function and quality of life after maxillary ablative surgery. However, irradiated patients showed a noticeable trend of higher implant failure, and this was influenced by tumour position and size impacting the radiation dose to the zygomatic bone.</p
Sialendoscopy increases saliva secretion and reduces xerostomia up to 60 weeks in Sjogren's syndrome patients:a randomized controlled study
OBJECTIVE: To assess the effect of sialendoscopy of the major salivary glands on salivary flow and xerostomia in patients with Sjögren's syndrome (SS). METHODS: Forty-five patients with SS were randomly assigned to a control group (no irrigation, control, n = 15), to irrigation of the major salivary glands with saline (saline, n = 15) or to irrigation with saline followed by corticosteroid application (triamcinolone acetonide in saline, saline/TA, n = 15). Unstimulated whole saliva flow (UWSF), chewing-stimulated whole saliva flow (SWSF), citric acid-stimulated parotid flow, Clinical Oral Dryness Score (CODS), Xerostomia Inventory (XI) and EULAR SS Patient Reported Index (ESSPRI) scores were obtained 1 week before (T0), and 1, 8, 16, 24, 36, 48 and 60 weeks after sialendoscopy. Data were analysed using linear mixed models. RESULTS: Irrespective of the irrigation protocol used, sialendoscopy resulted in an increased salivary flow during follow-up up to 60 weeks. Significant between-group differences in the longitudinal course of outcomes were found for UWSF, SWSF, XI and ESSPRI scores (P = 0.028, P = 0.001, P = 0.03, P = 0.021, respectively). UWSF at 60 weeks was higher compared with T0 in the saline group (median: 0.14 vs median: 0.10, P = 0.02) and in the saline/TA group (median: 0.20, vs 0.13, P = 0.035). In the saline/TA group SWSF at 48 weeks was higher compared with T0 (median: 0.74 vs 0.38, P = 0.004). Increase in unstimulated salivary flow was also reflected in improved CODS, XI and ESSPRI scores compared with baseline. CONCLUSION: Irrigation of the major salivary glands in patients with SS increases salivary flow and reduces xerostomia
Effects of aerobic exercise and cognitively engaging exercise on cardiorespiratory fitness and motor skills in primary school children:A cluster randomized controlled trial
This paper examined effects of two interventions on cardiorespiratory fitness and motor skills, and whether these effects are influenced by baseline levels, and dose of moderate-to-vigorous physical activity (MVPA) during the intervention. A cluster randomized controlled trial was implemented in 22 schools (n = 891; 9.2 ± 07 years). Intervention groups received aerobic or cognitively engaging exercise (14-weeks, four lessons per week). Control groups followed their regular physical education programme. Cardiorespiratory fitness, motor skills and MVPA were assessed. Multilevel analysis showed no main effects on cardiorespiratory fitness and motor skills although the amount of MVPA was higher in the aerobic than in the cognitively engaging and control group. Intervention effects did not depend on baseline cardiorespiratory fitness and motor skills. Children with a higher dose of MVPA within the intervention groups had better cardiorespiratory fitness after both interventions and better motor skills after the cognitively engaging intervention. In conclusion, the interventions were not effective to enhance cardiorespiratory fitness and motor skills at a group level, possibly due to large individual differences and to a total dose of MVPA too low to find effects. However, the amount of MVPA is an important factor that influence the effectiveness of interventions
Relations between gross motor skills and executive functions, controlling for the role of information processing and lapses of attention in 8-10 year old children
This study aimed to systematically investigate the relation between gross motor skills and aspects of executive functioning (i.e. verbal working memory, visuospatial working memory, response inhibition and interference control) in 8-10 year old children. Additionally, the role of information processing (speed and variability) and lapses of attention in the relation between gross motor skills and executive functions was investigated. Data of 732 Dutch children from grade 3 and 4 were analyzed (50.0% boys, 50.4% grade 3, age = 9.16 ± 0.64 years). Gross motor skills were assessed using three items of the Körper Koordinationstest fü r Kinder and one item of the Bruininks-Oseretsky test of Motor Proficiency, Second Edition. Executive functions were assessed using the Wechsler Digit Span task (verbal working memory), the Visuospatial Memory task (visuospatial working memory), the Stop Signal task (response inhibition) and a modified version of the Flanker task (interference control). Information processing and lapses of attention were obtained by applying an ex-Gaussian analysis on go trials of the Stop Signal task. Multilevel regression analysis showed that gross motor skills were significantly related to verbal working memory, visuospatial working memory and response inhibition, but not to interference control. Lapses of attention was a significant predictor for all executive functions, whereas processing speed was not. Variability in processing speed was only predictive for visuospatial working memory. After controlling for information processing and lapses of attention, gross motor skills were only significantly related to visuospatial working memory and response inhibition. The results suggest that after controlling for information processing and lapses of attention, gross motor skills are related to aspects of executive functions that are most directly involved in, and share common underlying processes with, gross motor skills
Immediate implant-retained prosthetic obturation after maxillectomy based on zygomatic implant placement by 3D-guided surgery:a cadaver study
Abstract Background The aim of this study was to introduce a complete 3D workflow for immediate implant retained prosthetic rehabilitation following maxillectomy in cancer surgery. The workflow consists of a 3D virtual surgical planning for tumor resection, zygomatic implant placement, and for an implant-retained prosthetic-obturator to fit the planned outcome situation for immediate loading. Materials and methods In this study, 3D virtual surgical planning and resection of the maxilla, followed by guided placement of 10 zygomatic implants, using custom cutting and drill/placement-guides, was performed on 5 fresh frozen human cadavers. A preoperatively digitally designed and printed obturator prosthesis was placed and connected to the zygomatic implants. The accuracy of the implant positioning was obtained using 3D deviation analysis by merging the pre- and post-operative CT scan datasets. Results The preoperatively designed and manufactured obturator prostheses matched accurately the per-operative implant positions. All five obturators could be placed and fixated for immediate loading. The mean prosthetic point deviation on the cadavers was 1.03 ± 0.85 mm; the mean entry point deviation was 1.20 ± 0.62 mm; and the 3D angle deviation was 2.97 ± 1.44°. Conclusions It is possible to 3D plan and accurately execute the ablative surgery, placement of zygomatic implants, and immediate placement of an implant-retained obturator prosthesis with 3D virtual surgical planning.The next step is to apply the workflow in the operating room in patients planned for maxillectomy
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