Skeletal Changes in Growing Cleft Patients with Class III Malocclusion Treated with Bone Anchored Maxillary Protraction-A 3.5-Year Follow-Up

This prospective controlled trial aimed to evaluate the skeletal effect of 3.5-years bone anchored maxillary protraction (BAMP) in growing cleft subjects with a Class III malocclusion. Subjects and Method: Nineteen cleft patients (11.4 +/- 0.7-years) were included from whom cone beam computed tomography (CBCT) scans were taken before the start of BAMP (T0), 1.5-years after (T1) and 3.5 y after (T2). Seventeen age- and malocclusion-matched, untreated cleft subjects with cephalograms available at T0 and T2 served as the control group. Three dimensional skeletal changes were measured qualitatively and quantitatively on CBCT scans. Two dimensional measurements were made on cephalograms. Results: Significant positive effects have been observed on the zygomaticomaxillary complex. Specifically, the A-point showed a displacement of 2.7 mm +/- 0.9 mm from T0 to T2 (p < 0.05). A displacement of 3.8 mm +/- 1.2 mm was observed in the zygoma regions (p < 0.05). On the cephalograms significant differences at T2 were observed between the BAMP and the control subjects in Wits, gonial angle, and overjet (p < 0.05), all in favor of the treatment of Class III malocclusion. The changes taking place in the two consecutive periods (Delta T1-T0, Delta T2-T1) did not differ, indicating that not only were the positive results from the first 1.5-years maintained, but continuous orthopedic effects were also achieved in the following 2-years. Conclusions: In conclusion, findings from the present prospective study with a 3.5-years follow-up provide the first evidence to support BAMP as an effective and reliable treatment option for growing cleft subjects with mild to moderate Class III malocclusion up to 15-years old

A comparative study of Monte Carlo-coupled depletion codes applied to a Sodium Fast Reactor design loaded with minor actinides

inor actinides (MAs) transmutation is a main design objective of advanced nuclear systems such as generation IV Sodium Fast Reactors (SFRs). In advanced fuel cycles, MA contents in final high level waste packages are main contributors to short term heat production as well as to long-term radiotoxicity. Therefore, MA transmutation would have an impact on repository designs and would reduce the environment burden of nuclear energy. In order to predict such consequences Monte Carlo (MC) transport codes are used in reactor design tasks and they are important complements and references for routinely used deterministic computational tools. In this paper two promising Monte Carlo transport-coupled depletion codes, EVOLCODE and SERPENT, are used to examine the impact of MA burning strategies in a SFR core, 3600 MWth. The core concept proposal for MA loading in two configurations is the result of an optimization effort upon a preliminary reference design to reduce the reactivity insertion as a consequence of sodium voiding, one of the main concerns of this technology. The objective of this paper is double. Firstly, efficiencies of the two core configurations for MA transmutation are addressed and evaluated in terms of actinides mass changes and reactivity coefficients. Results are compared with those without MA loading. Secondly, a comparison of the two codes is provided. The discrepancies in the results are quantified and discussed

Analysis of a Spanish energy scenario with Generation IV nuclear reactors

The advantages of fast-spectrum reactors consist not only of an efficient use of fuel through the breeding of fissile material and the use of natural or depleted uranium, but also of the potential reduction of the amount of actinides such as americium and neptunium contained in the irradiated fuel. The first aspect means a guaranteed future nuclear fuel supply. The second fact is key for high-level radioactive waste management, because these elements are the main responsible for the radioactivity of the irradiated fuel in the long term. The present study aims to analyze the hypothetical deployment of a Gen-IV Sodium Fast Reactor (SFR) fleet in Spain. A nuclear fleet of fast reactors would enable a fuel cycle strategy different than the open cycle, currently adopted by most of the countries with nuclear power. A transition from the current Gen-II to Gen-IV fleet is envisaged through an intermediate deployment of Gen-III reactors. Fuel reprocessing from the Gen-II and Gen-III Light Water Reactors (LWR) has been considered. In the so-called advanced fuel cycle, the reprocessed fuel used to produce energy will breed new fissile fuel and transmute minor actinides at the same time. A reference case scenario has been postulated and further sensitivity studies have been performed to analyze the impact of the different parameters on the required reactor fleet. The potential capability of Spain to supply the required fleet for the reference scenario using national resources has been verified. Finally, some consequences on irradiated final fuel inventory are assessed. Calculations are performed with the Monte Carlo transport-coupled depletion code SERPENT together with post-processing tools

Uncertainty analysis of Lead cross sections on reactor safety for ELECTRA

The Total Monte Carlo (TMC) method was used in this study to assess the impact of Pb-206, 207 and 208 nuclear data uncertainties on keff , βeff, coolant temperature coefficient, the coolant void worth for the ELECTRA reactor. Relatively large uncertainties were observed in the keff and the coolant void worth for all the isotopes with significant contribution coming from Pb-208 nuclear data. The large Pb-208 nuclear data uncertainty observed was further investigated by studying the impact of partial channels on the keff and the βeff. Various sections of ENDF file: elastic scattering (n, el), inelastic scattering (n, inl), neutron capture (n, γ), (n, 2n), resonance parameters and the angular distribution were varied randomly and distributions in keff and the βeff obtained. The dominant contributions to the uncertainty in the keff from Pb-208 came from uncertainties in the resonance parameters; however, elastic scattering cross section and the angular distribution also had significant impact. The impact of nuclear data uncertainties on the βeff was observed to be small

Three-Dimensional Cone Beam Computed Tomography (CBCT)-Derived Soft Tissue Changes in Patients with Unilateral Cleft Lip, Alveolus, and Palate with Midfacial Deficiency after 1.5 Years of Bone-Anchored Maxillary Protraction.

Background: Bone-anchored maxillary protraction (BAMP) aims to correct midfacial deficiencies, with proven positive skeletal changes without potential unwanted side effects. However, the influence of BAMP treatment on facial soft tissues, particularly in subjects with complete unilateral cleft lip, alveolus, and palate (CUCLAP), remains unclear. Methods: This single-center longitudinal cohort study examined the effects of 1.5 years of BAMP treatment on facial soft tissues in growing subjects with complete unilateral cleft lip, alveolus, and palate. The sample consisted of 25 patients, age range 9.7 to 12.6 years. Three-dimensional surface models derived from CBCT scans were superimposed on stable structures of the anterior cranial base and on the occipital area posterior of the foramen magnum to assess three-dimensional changes due to growth and BAMP therapy. Results: The results revealed a moderate positive correlation (Pearson's correlation coefficient from 0.203 to 0.560) between changes in hard tissue and soft tissue; some correlations were found to be weak (<0.300). Linear changes in soft tissue following BAMP were in the same direction as skeletal changes, showing downward, forward, and outward displacement. The only exception was in the vertical dimension. The lower facial third showed a slight but significant reduction, mainly in lip length (-1.2 mm), whereas the middle facial third showed a small increase (1.1 mm). Conclusions: It was concluded that during BAMP, soft tissue changes occur in the same direction as skeletal changes, although with a larger variability and less pronounced effects

Identifying prognostic factors for conservative treatment outcomes in servicemen with chronic exertional compartment syndrome treated at a rehabilitation center

Abstract Background Chronic exertional compartment syndrome (CECS) is a condition of pain induced by exercise, and it is characterized by muscle swelling and impaired muscle function in the lower leg. Given the diversity in the diagnosis and treatment of CECS, it is desirable to determine variables pertaining to prognosis and recovery. The purpose of this study is to identify prognostic factors for conservative treatment outcomes in servicemen with CECS who were treated at a Military Rehabilitation Center. Methods Patients from all military services were referred from the special unit for lower leg pain at the Central Military Hospital, Utrecht, the Netherlands. Descriptive analysis was used to report the characteristics of the participants and their baseline measurements. Group differences were analyzed using a Student’s t-test or Mann-Whitney U test, according to the normality of the data distribution. Differences between the pre- and post-intervention outcomes were evaluated using the Wilcoxon signed rank test. To evaluate the magnitude of prognostic factors, a univariate logistic regression analysis was performed. The prognostic factors included age, body mass index, body fat percentage, self-efficacy beliefs, foot malalignment, intramuscular pressure, other comorbidities, protein and creatine use, smoking, alcohol use, complaint duration, physical demands, and duration of military service. Results After the rehabilitation period, we observed 25 patients with a successful outcome, which was defined as a reduction in pain (≥ 2 points) during the capacity test measured using a verbal rating scale and 20 patients with an unsuccessful outcome. Factors demonstrating a limited increased odds ratio for an unsuccessful outcome included smoking, alcohol use, intramuscular pressure, a complaint duration of more than 6 months, and physical demands of service. However, these factors did not reach significance. Conclusion This study did not identify any prognostic factors that predict the outcome of a rehabilitation program for CECS. A larger sample using an identical design might provide further evidence regarding prognostic factors, which would facilitate development of a model that predicts the outcomes of a rehabilitation program for CECS

Post Irradiation Examination of Irradiated Americium Oxide and Uranium Dioxide in Magnesium Aluminate Spinel

To study MgAl2O4 spinel as inert matrix material for the transmutation of minor actinides, two capsules were irradiated at the high flux reactor in Petten, containing 12.5 wt% micro-dispersed 241AmOx in spinel and 25 wt% micro-dispersed enriched UO2 in spinel. During irradiation, the initially present 241Am was converted for 99.8% to fission products (50%), plutonium (30%), curium (16%) and 243Am (4%). The UO2 spinel target experienced a burn-up of 32% fission per initial metal atom. The post irradiation examination of the AmOx inert matrix target showed swelling of 27 vol.%, and a gas release of 48% for He and 16% for Xe and Kr. The UO2 inert matrix target also showed a large volumetric swelling of 11%, directed mainly radially. Ceramography on the UO2 inert matrix target revealed a complete restructuring of the spinel grains upon irradiation and the absence of porosity, suggesting that amorphisation is the main cause of the swelling.JRC.E-Institute for Transuranium Elements (Karlsruhe