| 1. |
- Tobin, Stephen, et al.
(författare)
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Nondestructive Assay Data Integration with the SKB-50 Assemblies - FY16 Update
- 2016
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Rapport (övrigt vetenskapligt/konstnärligt)abstract
- A project to research the application of non-destructive assay (NDA) techniques for spent fuel assemblies is underway at the Central Interim Storage Facility for Spent Nuclear Fuel (for which the Swedish acronym is Clab) in Oskarshamn, Sweden. The research goals of this project contain both safeguards and non-safeguards interests. These nondestructive assay (NDA) technologies are designed to strengthen the technical toolkit of safeguard inspectors and others to determine the following technical goals more accurately; Verify initial enrichment, burnup, and cooling time of facility declaration for spent fuel assemblies; Detect replaced or missing pins from a given spent fuel assembly to confirm its integrity; and Estimate plutonium mass and related plutonium and uranium fissile mass parameters in spent fuel assemblies. Estimate heat content, and measure reactivity (multiplication).
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| 2. |
- Farman, Helen H., 1983, et al.
(författare)
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Female Mice Lacking Estrogen Receptor-alpha in Hypothalamic Proopiomelanocortin (POMC) Neurons Display Enhanced Estrogenic Response on Cortical Bone Mass
- 2016
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Ingår i: Endocrinology. - : The Endocrine Society. - 0013-7227 .- 1945-7170. ; 157:8, s. 3242-3252
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Tidskriftsartikel (refereegranskat)abstract
- Estrogens are important regulators of bone mass and their effects are mainly mediated via estrogen receptor(ER)alpha. Central ER alpha exerts an inhibitory role on bone mass. ER alpha is highly expressed in the arcuate (ARC) and the ventromedial (VMN) nuclei in the hypothalamus. To test whether ER alpha in proopiomelanocortin (POMC) neurons, located in ARC, is involved in the regulation of bone mass, we used mice lacking ER alpha expression specifically in POMC neurons (POMC-ER alpha(-/-)). Female POMC-ER alpha(-/-) and control mice were ovariectomized (OVX) and treated with vehicle or estradiol (0.5 mu g/d) for 6 weeks. As expected, estradiol treatment increased the cortical bone thickness in femur, the cortical bone mechanical strength in tibia and the trabecular bone volume fraction in both femur and vertebrae in OVX control mice. Importantly, the estrogenic responses were substantially increased in OVX POMC-ER alpha(-/-) mice compared with the estrogenic responses in OVX control mice for cortical bone thickness (+ 126 +/- 34%, P < .01) and mechanical strength (+ 193 +/- 38%, P <.01). To test whether ER alpha in VMN is involved in the regulation of bone mass, ER alpha was silenced using an adeno-associated viral vector. Silencing of ER alpha in hypothalamic VMN resulted in unchanged bone mass. In conclusion, mice lacking ER alpha in POMC neurons display enhanced estrogenic response on cortical bone mass and mechanical strength. We propose that the balance between inhibitory effects of central ER alpha activity in hypothalamic POMC neuronsin ARC and stimulatory peripheral ER alpha-mediated effects in bone determines cortical bone mass in female mice.
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| 3. |
- Ohlsson, Claes, 1965, et al.
(författare)
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Increased adipose tissue aromatase activity improves insulin sensitivity and reduces adipose tissue inflammation in male mice.
- 2017
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Ingår i: American journal of physiology. Endocrinology and metabolism. - : American Physiological Society. - 1522-1555 .- 0193-1849. ; 313:4
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Tidskriftsartikel (refereegranskat)abstract
- Females are in general more insulin sensitive than males. To investigate if this is a direct effect of sex-steroids (SS) in white adipose tissue (WAT), we developed a male mouse model over expressing the aromatase enzyme, converting testosterone (T) to estradiol (E2), specifically in WAT (Ap2-arom mice). Adipose tissue E2 levels were increased while circulating SS levels were unaffected in male Ap2-arom mice. Importantly, male Ap2-arom mice were more insulin sensitive compared with WT mice and exhibited increased serum adiponectin levels and upregulated expression of Glut4 and Irs1 in WAT. The expression of markers of macrophages and immune cell infiltration was markedly decreased in WAT of male Ap2-arom mice. The adipogenesis was enhanced in male Ap2-arom mice, supported by elevated Pparg expression in WAT and enhanced differentiation of pre-adipocyte into mature adipocytes. In summary, increased adipose tissue aromatase activity reduces adipose tissue inflammation and improves insulin sensitivity in male mice. We propose that estrogen increases insulin sensitivity via a local effect in WAT on adiponectin expression, adipose tissue inflammation, and adipogenesis.
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| 4. |
- Zasciurinskiene, Egle, et al.
(författare)
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Outcome of orthodontic treatment in subjects with periodontal disease. Part III: a CBCT study of external apical root resorption.
- 2019
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Ingår i: European journal of orthodontics. - : Oxford University Press (OUP). - 1460-2210 .- 0141-5387. ; 41:6, s. 575-582
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Tidskriftsartikel (refereegranskat)abstract
- No evidence is present on the risk for external apical root resorption (EARR) during orthodontic treatment (OT) of adult patients with periodontal disease.To examine EARR after OT in subjects with periodontal disease and to analyse how intrusion and change in inclination of the most proclined maxillary incisors influence EARR.The study included 50 patients with periodontal disease. Sub-gingival debridement by ultrasonic instrumentation supplemented with hand instruments was performed by experienced dental hygienist after baseline examination for all patients. For the control group, final periodontal treatment (PT) was performed before orthodontic tooth movement. For the test group patients, final PT was performed after levelling and alignment phases were finished, before the active space closure with elastic chain and/or inter-arch elastic traction for sagittal correction was started. OT was performed with a straight-wire appliance. Micro-implants or implants were used for posterior anchorage. Cone beam computed tomography examinations were performed before and after OT. EARR of all single-rooted teeth were measured. EARR of the most proclined maxillary incisor was related to intrusion and change in inclination angle.EARR after OT was observed in median 80.7 per cent (interquartile range 22.02) of single-rooted teeth [mean 1.2 (standard deviation 0.44) mm]. In 82.3 per cent of teeth, EARR was 2 mm or less. Severe EARR was found in 8 per cent of patients and five maxillary incisors (less than 1 per cent of all teeth). The amount of intrusion and change in inclination angle of the most proclined maxillary central incisor influenced the extent of EARR. Mean EARR was significantly higher when OT lasted more than 18 months (P = 0.02).OT in conjunction with PT in periodontal patients resulted in EARR in 81 per cent of all single-rooted teeth. Intrusion and change in inclination angle of the most proclined maxillary central incisor influenced the extent of EARR, as did longer OT.
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| 5. |
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| 6. |
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| 7. |
- Zasciurinskiene, Egle, et al.
(författare)
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Outcome of periodontal-orthodontic treatment in subjects with periodontal disease. Part II: a CBCT study of alveolar bone level changes.
- 2019
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Ingår i: European journal of orthodontics. - : Oxford University Press (OUP). - 1460-2210 .- 0141-5387. ; 41:6, s. 565-574
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Tidskriftsartikel (refereegranskat)abstract
- To examine alveolar bone level (ABL) changes before (T1) and after (T2) orthodontic treatment (OT) in subjects with periodontal disease.The study included 50 subjects with periodontal disease. All patients received subgingival debridement following baseline examination. Control group patients received final periodontal treatment before the start of OT. For the test group patients final periodontal treatment was performed simultaneous to OT. OT was performed with a straight-wire appliance. Micro-implants or temporary crowns on implants were used for posterior anchorage when needed. ABL measurements of 3821 tooth surfaces were performed on cone beam computed tomography images.No difference was observed between mean ABL at T1 and T2. ABL remained unchanged on 69 per cent of surfaces. A mean of 15.6 (SD 7.4) per cent of surfaces experienced ABL gain, and a mean of 15.1 (SD 7.5) per cent was found with ABL loss. Small significant median ABL difference was observed on mesial and distal surfaces (P < 0.001). A significant difference was found between median ABL changes on mesial/distal in comparison to buccal/lingual surfaces (P < 0.01). Significantly more buccal (17.9 %) and lingual (18.5 %) surfaces experienced ABL loss when compared with mesial (11.3 %) and distal (12.0 %) surfaces (P < 0.001). Significant difference was found in the median ABL change of intruded (0.5 (IQR 0.94) mm) and non-intruded (-0.4 (IQR 1.07) mm) maxillary incisors (P = 0.04). Significant median ABL gain was found on the lingual surface of maxillary incisors, which were retroclined more than 8.6 degree and intruded more than 1.6 mm.ABL changes after periodontal-orthodontic treatment in patients with periodontal disease were small. ABL gain was more observed on mesial and distal surfaces and ABL loss on buccal and lingual surfaces. Larger orthodontic movements of maxillary incisors influenced ABL gain.
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| 8. |
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| 9. |
- Ekström, Ylva, 1971-, et al.
(författare)
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En studie om att leda digitala transformationer i komplexa verksamheter : Institutionella normer, fysiska rum och digitala verktyg
- 2021
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Rapport (övrigt vetenskapligt/konstnärligt)abstract
- Föreliggande rapport sammanfattar forskningsprojektet “Att leda digital transformation av fysiska rum” som genomförts av forskare vid Uppsala universitet i samverkan med tre partnerorganisationer: Uppsala stadsteater, Svenska Kyrkan, och en nordeuropeisk finanskoncern med huvudkontor i Sverige; projektet samfinansierades av Vinnova under åren 2019-2020. Projektets syfte var att utveckla kunskap om, och verktyg för förståelse av, hur det fysiska rummet och dess digitalisering påverkar interaktionen mellan aktörer bland annat med avseende på kommunikation, tillit och legitimitet. Projektet har genomförts som en komparativ studie av dessa tre tämligen skilda organisationer, som kommit olika långt i relation till digital transformation av deras respektive verksamheter. Forskarna har genomfört intervjuer och observationer på de tre partnerorganisationerna samt gemensamma och organisations-överskridande diskussioner och analyser vid ett flertal workshoppar, där såväl forskare som representanter från partnerorganisationerna deltagit. Rapporten presenterar resultat i form av beskrivningar av specifika situationer i respektive partnerorganisation med betoning på digitaliseringsprocesser med direkt inverkan på det fysiska rummet och de utmaningar som detta leder till. Vidare presenteras analyser och insikter i relation till utmaningarna som digitaliseringen kan ge upphov till och generella, normativa rekommendationer för att vägleda organisationer genom digitala transformationsprocesser. I analysen har framför allt institutionella logiker tillämpats som teoretiskt perspektiv. Studien påvisar betydelsen som de fysiska platserna (t.ex. kontor, scen) utgör för skilda verksamheter, och att användningen av digitala verktyg med syfte att eliminera användningen av fysiska platser kan ge upphov till oförutsedda konsekvenser.
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| 10. |
- Favalli, Andrea, et al.
(författare)
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Determining initial enrichment, burnup, and cooling time of pressurized-water-reactor spent fuel assemblies by analyzing passive gamma spectra measured at the Clab interim-fuel storage facility in Sweden
- 2016
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Ingår i: Nuclear Instruments and Methods in Physics Research Section A. - : Elsevier BV. - 0168-9002 .- 1872-9576. ; 820, s. 102-111
-
Tidskriftsartikel (refereegranskat)abstract
- The purpose of the Next Generation Safeguards Initiative (NGSI)–Spent Fuel (SF) project is to strengthen the technical toolkit of safeguards inspectors and/or other interested parties. The NGSI–SF team is working to achieve the following technical goals more easily and efficiently than in the past using nondestructive assay measurements of spent fuel assemblies: (1) verify the initial enrichment, burnup, and cooling time of facility declaration; (2) detect the diversion or replacement of pins; (3) estimate the plutonium mass [which is also a function of the variables in (1)]; (4) estimate the decay heat; and (5) determine the reactivity of spent fuel assemblies. Since August 2013, a set of measurement campaigns has been conducted at the Central Interim Storage Facility for Spent Nuclear Fuel (Clab), in collaboration with Swedish Nuclear Fuel and Waste Management Company (SKB). One purpose of the measurement campaigns was to acquire passive gamma spectra with high-purity germanium and lanthanum bromide scintillation detectors from Pressurized Water Reactor and Boiling Water Reactor spent fuel assemblies. The absolute 137Cs count rate and the 154Eu/137Cs, 134Cs/137Cs, 106Ru/137Cs, and 144Ce/137Cs isotopic ratios were extracted; these values were used to construct corresponding model functions (which describe each measured quantity’s behavior over various combinations of burnup, cooling time, and initial enrichment) and then were used to determine those same quantities in each measured spent fuel assembly. The results obtained in comparison with the operator declared values, as well as the methodology developed, are discussed in detail in the paper.
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| 11. |
- Grogan, B., et al.
(författare)
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NDA Measurement Analysis of Spent Nuclear Fuel Assemblies at the SwedishClab Facility Using the INDEPTH Code
- 2016
-
Konferensbidrag (övrigt vetenskapligt/konstnärligt)abstract
- A project to research the application of non-destructive assay (NDA) to spent fuel assemblies is underwayamong a team comprised of the European Commission, DG Energy, Directorate Safeguards; the SwedishNuclear Fuel and Waste Management Company; Uppsala University; and US national laboratories (LosAlamos National Laboratory, Lawrence Livermore National Laboratory, and Oak Ride NationalLaboratory). The research goals of this project combine safeguards goals (detection of missing/substitutedfuel pins and verification of operator declarations) and non-safeguards goals (estimation of decay heat andreactivity of each assembly). The final objective of this project is to quantify the capability of severalintegrated NDA instruments being developed to meet the aforementioned safeguards and non-safeguardsgoals using combined signatures of neutron, gamma-ray, and decay heat.In support of these goals, passive gamma and neutron measurements were made on 50 spent fuelassemblies at the Swedish Central Interim Storage Facility for Spent Nuclear Fuel (Clab) using high-purity germanium and Fork detectors. The Oak Ridge National Laboratory (ORNL) Inverse DepletionTheory (INDEPTH) code was used to reconstruct the spent fuel parameters (initial enrichment, burnup,and cooling time) for each assembly. INDEPTH uses a gradient-based search technique—combined withthe ORIGEN code for forward depletion calculations—to find the spent fuel parameters that result inpassive gamma and neutron outputs that best match the measurements. The results of the INDEPTHcalculations are presented and compared to the operator declarations (trusted in this case) in order toassess how accurately these parameters can be determined using current passive gamma and neutronmeasurements. These results will provide a baseline which can be used to assess whether and by howmuch new safeguards instruments being developed for NDA measurements can improve the accuracy ofreconstructed fuel parameter values.
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| 12. |
- Havsed, Kristian, et al.
(författare)
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Bacterial Composition and Metabolomics of Dental Plaque From Adolescents
- 2021
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Ingår i: Frontiers in Cellular and Infection Microbiology. - : Frontiers Media SA. - 2235-2988. ; 11
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Tidskriftsartikel (refereegranskat)abstract
- Supragingival dental plaque samples were collected from 40 Swedish adolescents, including 20 with caries lesions (CAR) and 20 caries-free (CF). Fresh plaque samples were subjected to an ex vivo acid tolerance (AT) test where the proportion of bacteria resistant to an acid shock was evaluated through confocal microscopy and live/dead staining, and the metabolites produced were quantified by 1H Nuclear Magnetic Resonance (1H NMR). In addition, DNA was extracted and the 16S rRNA gene was sequenced by Illumina sequencing, in order to characterize bacterial composition in the same samples. There were no significant differences in AT scores between CAR and CF individuals. However, 7 out of the 10 individuals with highest AT scores belonged to the CAR group. Regarding bacterial composition, Abiotrophia, Prevotella and Veillonella were found at significantly higher levels in CAR individuals (p=0.0085, 0.026 and 0.04 respectively) and Rothia and Corynebacterium at significantly higher levels in CF individuals (p=0.026 and 0.003). The caries pathogen Streptococcus mutans was found at low frequencies and was absent in 60% of CAR individuals. Random-forest predictive models indicate that at least 4 bacterial species or 9 genera are needed to distinguish CAR from CF adolescents. The metabolomic profile obtained by NMR showed a significant clustering of organic acids with specific bacteria in CAR and/or high AT individuals, being Scardovia wiggsiae the species with strongest associations. A significant clustering of ethanol and isopropanol with health-associated bacteria such as Rothia or Corynebacterium was also found. Accordingly, several relationships involving these compounds like the Ethanol : Lactate or Succinate : Lactate ratios were significantly associated to acid tolerance and could be of predictive value for caries risk. We therefore propose that future caries risk studies would benefit from considering not only the use of multiple organisms as potential microbial biomarkers, but also their functional adaptation and metabolic output.
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| 13. |
- Huang, Jing-Jia, 1990-
(författare)
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Surface-Controlled Chemical Vapor Deposition of Silicon Carbide
- 2022
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Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- Polycrystalline cubic silicon carbide, 3C-SiC, has long been investigated in the field of hard coating materials. The typical synthesis method for 3C-SiC coatings is thermal chemical vapor deposition (CVD) using either multicomponent precursors, e.g. methyltrichlorosilane, or a combination of single component precursors, e.g. silane and propane. In this thesis, the fabrication of polycrystalline SiC coatings has been explored from the new aspects on the basis of thermal CVD utilizing silicon tetrachloride (SiCl4) and various hydrocarbons, i.e. toluene (C7H8), methane (CH4) and ethylene (C2H4) as the precursors. The goal of this thesis is to control the surface chemistry in the SiCl4-based SiC CVD and has been accomplished by the following three different approaches: In the first approach to control the surface chemistry of SiC CVD, the difference in the adsorption energy of aromatic and aliphatic hydrocarbons on different SiC crystal planes was utilized. Under identical deposition conditions, a highly <111>-oriented 3C-SiC coating was deposited using C7H8 as the carbon precursor, whereas using CH4 resulted in a randomly oriented 3C-SiC. The results from quantum chemical calculation showed that the active film forming carbon species, i.e. C6H6 in the C7H8 process and CH3 in both C7H8 and CH4 processes, behaved differently when they adsorbed on the 3C-SiC (111) and (110) planes. CH3 is strongly chemisorbed on both planes, while C6H6 is chemisorbed on the (111) plane, but only physiosorbed on the other. The significant difference in the adsorption energy of CH3 and C6H6 on the (111) and (110) planes therefore explains the resulting highly <111>-oriented 3C-SiC from the C7H8 process. Furthermore, the ability to deposit 3C-SiC coatings with alternating highly <111>- and randomly oriented layers by merely switching the carbon precursor between C7H8 and CH4 or C2H4 in a single CVD deposition has further proven that the effect of aromatic hydrocarbons on the preferred growth orientation of 3C-SiC was controlled primarily by the surface chemistry. The second approach to the surface-controlled SiC CVD was based on the reduction of surface reaction probability (β) for conformal film growth via low-temperature, low-pressure CVD, which was originally proposed by Abelson and Girolami. Their strategies in reducing β, including lowering the temperature and increasing the precursor partial pressure, were successfully adapted to the SiC CVD growth using SiCl4 and C2H4 as the precursors in this thesis, where an elevated temperature and a moderate pressure were used. Moreover, the addition of Cl species as a growth inhibitor to the process further reduced the β, leading to a superconformal SiC growth. The third approach employed in this thesis for the SiC growth was pulsed CVD. Instead of a continuous and simultaneous SiCl4 and C2H4 flow, the precursors were pulsed alternately into the chamber with each precursor pulse being separated by a H2 purge. In this precursor delivery mode, the gas phase reactions between SiCl4 and C2H4 were avoided and hence the SiC growth was mostly controlled by the surface chemistry. Altering the pulse durations of the precursors led to a variation of growth per cycle (GPC), which was explained by a two-step mechanism. During the SiCl4 pulse, a thin layer of Si is deposited, which is carburized by carbon species produced during the C2H4 pulse. Additionally, the separation of precursor pulses should lead to a large increase in the surface coverage of Cl species, further enhancing the inhibition effect and resulting in a superconformal SiC growth. By using this approach, superconformal SiC coatings were achieved at temperatures where conventional CVD only yielded nonconformal SiC coatings. The observed decline in coating conformality with an elongated purge implied that more surface Cl species were replaced by H during the H2 purge and consequently the inhibition effect was diminished.
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| 14. |
- Ianakiev, Kiril, et al.
(författare)
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Underwater Testing of Detectors and Electronics Hardware for Spent Fuel Measurements
- 2015
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Konferensbidrag (övrigt vetenskapligt/konstnärligt)abstract
- Underwater gamma and neutron spent fuel measurement techniques are being researched to meet thecombined needs of the international safeguards community and the Swedish Nuclear Fuel and WasteManagement Company (SKB), which is responsible for fuel encapsulation and repository operation inSweden. Both SKB and the involved regulators anticipate measuring each spent fuel assemblyindividually before encapsulation; such a measurement plan presents a real challenge for the performanceand long-term behavior of detectors and electronics hardware. The reliability and radiation hardness of theelectronics and detectors are a big challenge for users of this technology. For instance, the gammadetectors and electronics may have to operate at count rates up to few million counts per second whilemaintaining good spectral resolution to detect lines from 137Cs, 134Cs, and 152Eu. If the 10B proportionalcounters are to replace the difficult-to-transport 235U fission chambers, they must tolerate a gamma doserate of many thousand R/h (many tens of Sv/h) without gain changes due to space charge effects or long-term degradation of the gas mixture. To address these challenges, a special underwater enclosure wasdeveloped for testing these detectors and electronics in parallel with the design and deployment ofnondestructive assay options for characterization of the spent fuel. In this paper we describe the hardwareand modeling components of the testing setup.
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| 15. |
- Jansson, Peter, 1971-, et al.
(författare)
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Axial and azimuthal gamma scanning of nuclear fuel - implications for spent fuel characterization
- 2016
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Ingår i: Journal of Nuclear Materials Management. - 0893-6188. ; 45:1, s. 34-47
-
Tidskriftsartikel (refereegranskat)abstract
- A project to research the application of non-destructive assay (NDA) to spent fuel assemblies is underway among a team comprised of the European Commission, DG Energy, Directorate Nuclear Safeguards; the Swedish Nuclear Fuel and Waste Management Company; Uppsala University, The University of Michigan, Los Alamos National Laboratory, Lawrence Livermore National Laboratory and Oak Ridge National Laboratory that collaboratively are advancing some of the goals of the Next Generation Safeguards Initiative’s Spent Fuel (NGSI-SF) Project. The NGSI–SF team is working to achieve the following technical goals more easily and efficiently using nondestructive assay measurements of spent fuel assemblies in order to improve both international safeguards and repository safety: (1) verify the initial enrichment, burnup, and cooling time of facility declaration; (2) detect the diversion or replacement of pins, (3) estimate the plutonium mass, (4) estimate the decay heat, and (5) determine the reactivity of spent fuel assemblies. The measured neutron, gamma-ray and heat signatures from spent fuel assemblies, as well as simulations, will be combined in advancement of the technical goals.This current study focuses primarily on the application of time stamped list mode data acquisition applied in the context of a fixed collimator that allowed a thin axial portion of the fuel to be observed as the fuel assembly moved vertically past the collimator. Measurements were performed at the Central Interim Storage Facility for Spent Nuclear Fuel (which is abbreviated using the Swedish acronym: Clab) in Sweden, in 2013 and 2014. In total, 50 spent nuclear fuel assemblies were measured in detail, 25 BWR and 25 PWR assemblies.In this context, time stamped list mode data acquisition have not previously been used for gamma-ray spectroscopy measurements of used nuclear fuel measurements. We compare it to the more typical fixed-axial location pulse height analysis approach. The flexibility of analyzing data from time stamped list mode measurements enables research into questions of how beneficial axially resolved information is for each of the varied research goals; in particular the current research is an initial step toward comparing the benefit of several fixed axial measurements vs. scanning an entire assembly.
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| 16. |
- Jansson, Peter, 1971-, et al.
(författare)
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Experimental Comparison between High Purity Germanium and Scintillator Detectors for Determining Burnup, Cooling Time and Decay Heat of Used Nuclear Fuel
- 2014
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Konferensbidrag (övrigt vetenskapligt/konstnärligt)abstract
- A experimental study of the gamma-ray energy spectra from used nuclear fuel has been performed. Four types of detectors were used to measure spectra from three PWR used fuel assemblies stored at the interim storage for used fuel in Sweden, CLAB: HPGe, LaBr3, NaI and BGO.The study was performed in the context of used fuel characterization for the back end of the fuel cycle in Sweden. Specifically, the purpose was to evaluate the behaviour of the different scintillator detectors (LaBr3, NaI and BGO) and their ability to be used instead of HPGe detectors when determining spent fuel parameters such as burnup, cooling time and decay heat of the used fuel.This paper presents results from the experimental study and an analysis of the capability of the detectors for used fuel characterization. The results shown are important when designing systems for used fuel characterization, e.g. for determining decay heat or fuel parameters concerning safeguards.
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| 17. |
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| 18. |
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| 19. |
- Jiang, Nan, et al.
(författare)
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Experiences of xerostomia after radiotherapy in patients with head and neck cancer : A qualitative study.
- 2018
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Ingår i: Journal of Clinical Nursing. - : John Wiley & Sons. - 0962-1067 .- 1365-2702. ; 27:1-2, s. e100-e108
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Tidskriftsartikel (refereegranskat)abstract
- AIMS AND OBJECTIVES: To describe the experiences of radiation-induced xerostomia in patients with head and neck cancer. BACKGROUND: Xerostomia is the most commonly occurring complication during and following radiotherapy. It can persist for several months or years and can have a significant impact on patients' quality of life. DESIGN: This was a qualitative descriptive study. METHODS: Semi-structured interviews were conducted with a sample of 20 participants. Inductive content analysis was used to analyse the qualitative data. RESULTS: Analysis of the manifest content identified five categories: communication problems, physical problems, psychosocial problems, treatment problems and relief strategies. The latent content was formulated into a theme: due to lack of information from professionals, the patients had to find their own solutions for their problems. CONCLUSIONS: Xerostomia is not only a biophysical symptom but also has a profound effect on the emotional, intellectual and sociocultural dimensions of life. The majority of patients continued to suffer from xerostomia and its associated symptoms after radiotherapy, in part, because of a lack of professional support, including the inability of nurses to provide oral health care. RELEVANCE TO CLINICAL PRACTICE: Nurses need to be knowledgeable about the effects of radiotherapy on oral mucosa and about appropriate interventions. The healthcare system requires a symptom management platform for radiation-induced complications, to help patients, their families and healthcare professionals obtain information about self-care, treatments and relief strategies.
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| 20. |
- Monstad, Therese, 1973-, et al.
(författare)
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The Communicative Constitution of Organizations in an Era of Re-materialization : A Case Study of Three Organizations
- 2024. - 1 uppl
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Ingår i: Organizational Communication in the Digital Era. - Cham : Springer Nature. - 9783031583063 - 9783031583070 ; , s. 253-272
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Bokkapitel (refereegranskat)abstract
- This chapter discusses the challenges and opportunities of digital transformation from the perspective of three organizations based on continuous interview and observation data gathered between late 2018 and the end of 2020. The purpose of such a discussion is to understand the importance of spatial co-existence and the significance of spatiality for meaningful organizational interaction. In other words—what happens to organizational members and the constitution, preservation and development of organizations, when the activity of “work” becomes detached from space? Of course, space or location matters more for some than others. For a telemarketer, space might be entirely insignificant, while for the priest and church-goer or the actor and theater-goer, the act of “going” somewhere to experience something is as important as what happens at the location, making the church and stage places that in themselves carry significance. This importance is represented in how churches and theater buildings often are majestic architectural achievements similar to other institutions of cultural, societal or financial importance that are housed in impressive locations such as banks, governments, court houses and universities.To discuss these questions, we draw on theories and perspectives of the communicative constitution of organizations (CCO) (e.g., Brummans et. al., 2014; Cooren, 2006; Putnam & Nicotera, 2009; Schoeneborn et al., 2018; Taylor & Van Every, 2000), and present a Sweden-based multisite case study (Ekström et al., 2021) of digital transformation consisting of three organizations whose common trait is that their core activities have historically speaking been dependent on either a physical location, physical spaces or face-to-face meetings. The three organizations in question are a major European financial institute, a church organization and a city theater—all institutions of traditional architectural and societal importance. As our relationship with these organizations deepened over the course of the pandemic, it allowed us as researchers to glimpse how digitalization has affected each one over time, and how each organization’s perspective of the challenges and opportunities of digitalization shifted and evolved before and throughout the pandemic.
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| 21. |
- Pakpour, Amir H., et al.
(författare)
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Predictors of oral health-related quality of life in Iranian adolescents : A prospective study.
- 2018
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Ingår i: Journal of Investigative and Clinical Dentistry. - : John Wiley & Sons. - 2041-1618 .- 2041-1626. ; 9:1
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Tidskriftsartikel (refereegranskat)abstract
- AIM: In the present study, we evaluated the direct and mediating (indirect) effects of clinical oral conditions, dental anxiety, sense of coherence (SOC), and socioeconomic variables on oral health-related quality of life (OHRQoL) and general health-related quality of life (GHRQoL) in Iranian adolescents.METHODS: A longitudinal design was used with a sample of 1052 (694 males, mean age=15.05 years) schoolchildren from Qazvin, Iran. Each participant completed a background information sheet and the following scales at baseline: Modified Dental Anxiety Scale, SOC, PedsQL 4.0 Generic Core Scale, and PedsQL Oral Health Scale. The PedsQL 4.0 Generic Core and Oral Health scales were recompleted at the 18-mo follow up.RESULTS: Father's education, monthly family income, dental anxiety, Community Periodontal Index (CPI), decayed, missing, and filled teeth (DMFT), and SOC significantly and directly predicted OHRQoL at 18 mo. Father's education had indirect effects on OHRQoL through CPI and DMFT, family income had indirect effects through DMFT, and dental anxiety had indirect effects through CPI. OHRQoL at 18 mo (β=0.499) and SOC (β=0.084) had significant and direct and mediating effects through OHRQoL on GHRQoL, while father's education, monthly family income, dental anxiety, CPI, and DMFT only showed mediating effects.CONCLUSIONS: Clinical oral indicators had direct effects on OHRQoL, but mediated the effects of dental anxiety and socioeconomic status on both OHRQoL and GHRQoL.
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| 22. |
- Solans, Virginie, et al.
(författare)
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Evaluating Peak Area Uncertainties in Connection to Passive Gamma Measurements of Spent Nuclear Fuel
- 2021
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Ingår i: Proceedings. - 9789295064355
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Konferensbidrag (refereegranskat)abstract
- In many countries, spent nuclear fuel is planned to be stored in a geological repository. Before the final encapsulation, safety parameters such as decay heat, criticality, and dose rate need to be ensured. A gamma scan of the spent nuclear fuel assemblies in the pool can extract valuable information needed to verify or update the declared values before the encapsulation. Gamma scans can be used to esti mate values such as burnup, cooling time, or initial enrichment [1], but also decay heat [2]. This paper presents results from a fullenergy peak area evaluation study of experimental gammaray spectra acquired from measurements using a highpurity germanium detector on 47 spent nuclear fuel assemblies from Sweden in 2016 and 2019. The assemblies chosen are UO2 fuel and represent a large span in cooling time, burnup, and initial enrichment [3]. The gamma spectra were acquired in the spent fuel pool of the Clab facility. As part of the measurement analysis, one wishes to determine the fullenergy net peak areas associated with selected fission products. This work presents results obtained using different methods to evaluate the fullenergy peak areas, including the use of different background estimations.In the determination of important safety parameters using gamma spectroscopy, it is crucial to consider uncertainties originating in the peak area analysis. The un certainty from the fullenergy peak area without the background has been evaluated and compared between the different models.
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| 23. |
- Tobin, Stephen, et al.
(författare)
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Experimental and Analytical Plans for the Non-destructive Assay System of the Swedish Encapsulation and Repository Facilities
- 2014
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Konferensbidrag (övrigt vetenskapligt/konstnärligt)abstract
- The Swedish Nuclear Fuel and Waste Management Company (SKB), European Atomic Energy Community (Euratom), two universities and several U.S. Department of Energy Laboratories have joined in a collaborative research effort to determine the capability of non-destructive assay (NDA) techniques to meet the combined needs of the safeguards community and the Swedish encapsulation and repository facilities operator SKB. These needs include partial defect detection, heat quantification, assembly identification (initial enrichment, burnup and cooling time), and Pu mass and reactivity determination. The experimental component of this research effort involves the measurement of 50 assemblies at the Central Storage of Spent Nuclear Fuel (Clab) facility in Sweden, 25 of which were irradiated in Pressurized Water Reactors and 25 in Boiling Water Reactors. The experimental signatures being measured for all assemblies include spectral resolved gammas (HPGe and LaBr3), time correlated neutrons (Differential Die-away Self Interrogation), time-varying and continuous active neutron interrogation (Differential Die-away and an approximation of Californium Interrogation Prompt Neutron), total neutron and total gamma fluxes (Fork Detector), total heat (assembly length calorimeter) and possibly the Cerenkov light emission (Digital Cerenkov Viewing Device). This paper fits into the IAEA’s Department of Safeguards Long-Term R&D Plan in the context of developing “more sensitive and less intrusive alternatives to existing NDA instruments to perform partial defect test on spent fuel assembly prior to transfer to difficult to access storage,” as well as potentially supporting pyrochemical processing. The work describes the specific measured signatures, the uniqueness of the information contained in these signatures and why a data mining approach is being used to combine the various signatures to optimally satisfy the various needs of the collaboration. This paper will address efficient and effective verification strategies particularly in the context of encapsulation and repository facilities.
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| 24. |
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| 25. |
- Vaccaro, Stefano, et al.
(författare)
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PWR and BWR spent fuel assembly gamma spectra measurements
- 2016
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Ingår i: Nuclear Instruments and Methods in Physics Research Section A. - : Elsevier BV. - 0168-9002 .- 1872-9576. ; 833, s. 208-225
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Tidskriftsartikel (refereegranskat)abstract
- A project to research the application of nondestructive assay (NDA) to spent fuel assemblies is underway. The research team comprises the European Atomic Energy Community (EURATOM), embodied by the European Commission, DG Energy, Directorate EURATOM Safeguards; the Swedish Nuclear Fuel and Waste Management Company (SKB); two universities; and several United States national laboratories. The Next Generation of Safeguards Initiative–Spent Fuel project team is working to achieve the following technical goals more easily and efficiently than in the past using nondestructive assay measurements of spent fuel assemblies: (1) verify the initial enrichment, burnup, and cooling time of facility declaration; (2) detect the diversion or replacement of pins, (3) estimate the plutonium mass, (4) estimate the decay heat, and (5) determine the reactivity of spent fuel assemblies. This study focuses on spectrally resolved gamma-ray measurements performed on a diverse set of 50 assemblies [25 pressurized water reactor (PWR) assemblies and 25 boiling water reactor (BWR) assemblies]; these same 50 assemblies will be measured with neutron-based NDA instruments and a full-length calorimeter. Given that encapsulation/repository and dry storage safeguards are the primarily intended applications, the analysis focused on the dominant gamma-ray lines of 137Cs, 154Eu, and 134Cs because these isotopes will be the primary gamma-ray emitters during the time frames of interest to these applications. This study addresses the impact on the measured passive gamma-ray signals due to the following factors: burnup, initial enrichment, cooling time, assembly type (eight different PWR and six different BWR fuel designs), presence of gadolinium rods, and anomalies in operating history. To compare the measured results with theory, a limited number of ORIGEN-ARP simulations were performed.
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| 26. |
- Vo, Duc, et al.
(författare)
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Determination of initial enrichment, burnup, and cooling time of pressurized-water-reactor spent fuel assemblies by analysis of passive gamma spectra measured at the Clab interim-fuel storage facility in Sweden
- 2015
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Konferensbidrag (refereegranskat)abstract
- The purpose of the Next Generation Safeguards Initiative (NGSI)-Spent Fuel (SF) project is to strengthen the technical toolkit of safeguards inspectors and/or others. NGSI-spent fuel is working to achieve the following technical goals more easily and efficiently than in the past using nondestructive assay (NDA) measurements of spent fuel assemblies: (1) verify the initial enrichment, burnup, and cooling time of facility declaration, (2) detect the diversion or replacement of pins, (3) quantify the plutonium mass in spent fuel [which is also a function of the variables in (1)], (4) estimate the decay heat, and (5) estimate the reactivity. In the first phase of the NGSI initiative, libraries of virtual pressurized-water-reactor (PWR) spent fuel assemblies were developed as a function of various reactor conditions. Simulated passive gamma-ray spectra were analyzed, along with a range of other NDA techniques, to investigate a methodology to determine initial enrichment, burnup, and cooling time. In the context of passive gamma research, a set of equations that quantifies the 137Cs count rate, 134Cs/137Cs count-rate ratio, and 154Eu/137Cs count-rate ratio was constructed as a model to extract those parameters. In the second phase of the project, an experimental activity was undertaken. Since August 2013 a set of measurement campaigns has been conducted at the Central Interim Storage Facility for Spent Nuclear Fuel (Clab), in collaboration with Swedish Nuclear Fuel and Waste Management Company (SKB). One purpose of the measurement campaigns was to acquire passive gamma spectra with high-purity germanium and lanthanum bromide scintillation detectors from PWR and boiling-water-reactor spent fuel assemblies. The absolute 137Cs count rate and the 154Eu/137Cs, 134Cs/137Cs, 106Ru/137Cs, and 144Ce/137Cs ratios were extracted by the Fixed energy Response function Analysis with Multiple efficiencies (FRAM) code. The values have been used to construct corresponding model functions, which describe each measured quantity’s behavior over various combinations of burnup, cooling time, and initial enrichment, and were used to determine those same quantities in each measured spent fuel assembly. The results obtained in comparison with the operator declared values, as well as the methodology developed, will be discussed in detail.
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| 27. |
- Vo, Duc, et al.
(författare)
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Passive gamma analysis of the boiling-water-reactor assemblies
- 2016
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Ingår i: Nuclear Instruments and Methods in Physics Research Section A. - : Elsevier BV. - 0168-9002 .- 1872-9576. ; 830, s. 325-337
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Tidskriftsartikel (refereegranskat)abstract
- This research focused on the analysis of a set of stationary passive gamma measurements taken on the spent nuclear fuel assemblies from a boiling water reactor (BWR) using pulse height analysis data acquisition. The measurements were performed on 25 different BWR assemblies in 2014 at Sweden's Central Interim Storage Facility for Spent Nuclear Fuel (Clab). This study was performed as part of the Next Generation of Safeguards Initiative–Spent Fuel project to research the application of nondestructive assay (NDA) to spent fuel assemblies. The NGSI–SF team is working to achieve the following technical goals more easily and efficiently than in the past using nondestructive assay (NDA) measurements of spent fuel assemblies: (1) verify the initial enrichment, burnup, and cooling time of facility declaration; (2) detect the diversion or replacement of pins, (3) estimate the plutonium mass, (4) estimate the decay heat, and (5) determine the reactivity of spent fuel assemblies. The final objective of this project is to quantify the capability of several integrated NDA instruments to meet the aforementioned goals using the combined signatures of neutrons, gamma rays, and heat.This report presents a selection of the measured data and summarizes an analysis of the results. Specifically, trends in the count rates measured for spectral lines from the following isotopes were analyzed as a function of the declared burnup and cooling time:137Cs, 154Eu, 134Cs, and to a lesser extent, 106Ru and 144Ce. From these measured count rates, predictive algorithms were developed to enable the estimation of the burnup and cooling time. Furthermore, these algorithms were benchmarked on a set of assemblies not included in the standard assemblies set used by this research team.
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| 28. |
- Wohlfahrt, J. C., et al.
(författare)
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A novel non-surgical method for mild peri-implantitis- a multicenter consecutive case series
- 2017
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Ingår i: International Journal of Implant Dentistry. - : Springer. - 2198-4034. ; 3:1
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Tidskriftsartikel (refereegranskat)abstract
- AIM:The aim of the present study was to evaluate the effect on peri-implant mucosal inflammation from the use of a novel instrument made of chitosan in the non-surgical treatment of mild peri-implantitis across several clinical centers.MATERIALS AND METHODS:In this 6-month multicenter prospective consecutive case series performed in six different periodontal specialist clinics, 63 implants in 63 patients were finally included. The subjects had mild peri-implantitis defined as radiographic bone loss of 1-2 mm, pocket probing depth (PPD) ≥4 mm and a positive bleeding on probing (mBoP) score. The patients were clinically examined at baseline and after 2, 4, 12 and 24 weeks, and radiographs were taken at baseline and at 3 and 6 months. Treatment of the implants with the chitosan brush seated in an oscillating dental drill piece was performed at baseline and at 3 months. Reductions in the clinical parameters (PPD and mBoP) were compared between baseline and the later examination time points.RESULTS:Significant reductions in both PPD and mBoP were observed at all time points compared with the baseline clinical measurements (p < 0.001). The mean PPD and mBoP at baseline were 5.15 mm (4.97; 5.32) and 1.86 (1.78; 1.93), respectively, whereas the mean PPD and mBoP at 6 months were 4.0 mm (3.91; 4.19) and 0.64 (0.54; 0.75), respectively. Stable reductions in PPD and mBoP were evident up to 6 months after the initial treatment and 3 months after the second treatment. All 63 implants were reported to have stable radiographic levels of osseous support.CONCLUSIONS:This case series demonstrated that an oscillating chitosan brush is safe to use and seems to have merits in the non-surgical treatment of dental implants with mild peri-implantitis. To measure the effectiveness of the method, a multicenter randomized clinical trial needs to be undertaken.
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| 29. |
- Zasčiurinskienė, Eglė, et al.
(författare)
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Orthodontic treatment simultaneous to or after periodontal cause-related treatment in periodontitis susceptible patients. Part I: Clinical outcome. A randomized clinical trial
- 2018
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Ingår i: Journal of Clinical Periodontology. - : Wiley. - 0303-6979 .- 1600-051X. ; 45:2, s. 213-224
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Tidskriftsartikel (refereegranskat)abstract
- AimTo compare two treatment strategies regarding the effect of orthodontic treatment on periodontal status in patients with plaque-induced periodontitis. Subjects and MethodsThis was a randomized clinical trial. Fifty periodontal patients were randomly assigned to the test or control groups according to periodontal treatment timing. All patients received supra- and subgingival debridement following baseline examination. Control group patients received cause-related periodontal treatment before the start of orthodontic treatment and which was performed simultaneous to orthodontic treatment for the test group patients. ResultsNo difference between the test and control groups was found regarding change of clinical attachment level (CAL) after periodontal-orthodontic treatment. Fewer sites with initial pocket depth (PD) of 4-6mm healed after periodontal-orthodontic treatment in the test group (20.5%, IQR=11.9%) in comparison with controls (30.4%, IQR=27.1%) (p=.03). Anterior teeth [OR 2.5] and teeth in male patients [OR 1.6] had a greater chance for PD improvement 2mm. Total periodontal-orthodontic treatment duration was significantly longer for the control group (p<.01). ConclusionsBoth groups showed a gain of CAL and a reduction in sites with PD 4mm. Orthodontic treatment, simultaneously to the periodontal treatment, could be used in the routine treatment of patients with plaque-induced periodontitis.
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| 30. |
- Zasčiurinskienė, Eglė
(författare)
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Studies on orthodontic treatment in subjects with periodontal disease
- 2018
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Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- The thesis focuses on periodontal-orthodontic treatment of adult subjects with periodontal disease.Aims: The overall aim of this thesis was to explore the effects, risks and benefits of periodontal-orthodontic treatment on periodontal tissues in subjects with periodontal disease.Methods: The research was conducted through a systematic literature review (Study 1), a randomised controlled trial (Study 2) and cone beam computed tomography examinations (Studies 3 and 4). The clinical part of the thesis was designed as a randomised controlled trial, which aimed to compare two periodontal treatment timing strategies regarding the effect of orthodontic treatment on periodontal status (Study 2). Fifty subjects with periodontal disease were randomly assigned either to the test (periodontal treatment simultaneous with orthodontic treatment) or control group (periodontal treatment before the start of orthodontic treatment). Initial treatment included oral hygiene instruction, supra- and sub-gingival debridement and was performed for all study patients. Nonsurgical and subsequent surgical periodontal treatment was performed at different time points for the test and control groups. Orthodontic treatment was performed with a straight-wire appliance. Clinical attachment level (CAL) change was chosen as a primary outcome variable. All patients were examined by cone beam computed tomography (CBCT) before and after orthodontic treatment to explore the extent of external apical root resorption (EARR) (Study 3) and changes in alveolar bone levels (ABL) (Study 4).Results: The findings in the systematic literature review yielded absence of randomized controlled trials orcontrolled clinical trials on comprehensive orthodontic treatment in subjects with periodontal disease. No difference in CAL change, EARR and ABL was found whether orthodontic treatment was performed simultaneously with (test group patients) or after (control group patients) periodontal treatment. Results yielded a median CAL change (sites CAL ≥4 mm) of 0.4 mm (Q1, Q3: 0.19, 0.61). Gain in clinical attachment level was observed in 22 (88%) patients in both treatment groups. CAL remained unchanged in an average of 3/4 of the sites; CAL gain was observed in an average of 1/4 of the sites. Root lengths were shortened in a median of 80.7% (Q1, Q3: 68.0, 90.0) of orthodontically moved teeth with a mean EARR of 1.2 mm (SD 0.44). EARR of <2 mm was observed in 82% of teeth. ABL levels remained unchanged on a mean of 69.3% (SD 8.8) of surfaces, ABL improved on a mean of 15.6% (SD 7.4) of surfaces, more on the mesial and distal, and ABL decreased on a mean of 15.1% (SD 7.5) of surfaces, more on the buccal and lingual.Conclusions: Based on the results of the present research it can be concluded that periodontal-orthodontic treatment under optimal conditions (experienced clinicians and patients with excellent oral hygiene routines overtime), if needed, could be included in the rehabilitation of patients with periodontal disease without deleterious effects. However, there are two important prerequisites: meticulous personal oral hygiene of the patient and optimal sub-gingival control of inflammation before and throughout the combined treatment.
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