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Radionuclide monitoring is a proven means of non-intrusive verification of the nuclear test ban treaty. In addition to that, the potential use of radionuclide monitoring spans beyond the detection of nuclear test explosions, since radionuclides can also be released and detected from operations of nuclear fuel cycle facilities, such as the reactor operation and nuclear reprocessing of plutonium production. In this work, we consider the use of coincidence and anticoincidence techniques as a means to increase the sensitivity in radionuclide monitoring, in terms of improved minimum detectable amount for radionuclides of interest to filter stations used in radionuclide monitoring. In particular, a multi-detector setup is currently being prepared for the evaluation of the technique, and to provide validation data for a coincidence detector simulation codes. In this presentation, we will describe the multi-detector setup assembled for enabling the evaluation of various types of spectrometry, including 1) gamma-gamma coincidence (from dual detectors and up to five High Purity Germanium (HPGe) detectors), 2) anticoincidence using BGO active shield with single HPGe detector, as well as use of multiple detectors in add-back mode, i.e. simply using the combined detector volume for increased efficiency of single gamma rays. We will present the results of measurements of a calibration sample, and provide a discussion on the advantages and disadvantages of the tested techniques in the context of radionuclide monitoring.

This article explores conditions for implementing shared decision-making(SDM) in coordinated individual care planning (CIP) with individuals withcomplex mental health needs. SDM in CIP are described as central,although such user centred collaboration still remains to be realised.Research underlines the need for a changed way of working, whereuser expertise is valued and a balance of power is promoted. The aimof the present study is to investigate the conditions for implementingSDM in connection with CIP for and with people with mental illness. Tobetter understand the context and conditions that can promote such animplementation, altogether 15 participants were interviewed in threeregions in Sweden within the scope of a stakeholder analysis. Bothhindering and supporting factors were identified with respect to animplementation process, such as staffturnover, differences in workculture and committed leadership. Further focus should be directedspecifically towards professionals working more closely with CIP andtowards in-depth analysis of the construct of culture in terms ofimplementation processes.

Postirradiation examination of nuclear fuel is routinely performed to characterize the important properties of current and future fuel. Gamma emission tomography is a proven noninvasive technique for this purpose. Among various measurement elements of the technique, a gamma-ray detector is an important element whose spectroscopic abilities and detection efficiency affect the overall results. Finding a combination of high detection efficiency and excellent energy resolution in a single detector is often a challenge. We have designed a novel planar segmented high-purity germanium detector that offers simultaneous measurement in six lines of sight with excellent energy resolution. The simultaneous detection ability enables faster data acquisition in a tomographic measurement, which may facilitate achieving higher spatial resolution. In this work, we have demonstrated the first use of the detector by performing a full tomographic measurement of mockup fuel rods. Two methods of detector data analysis were used to make spectra, and the images (tomograms) were reconstructed using the filtered back projection algorithm. The reconstructed images validate the successful use of the detector for tomographic measurement. The use of the detector for real fuel measurement is being planned and will be performed in the near future.

Lifespan is reduced by approximately 15 years in individuals suffering from severe mental illnesses such as schizophrenia spectrum disorders. Contributing to this is an increased prevalence of metabolic syndrome, an assortment of factors that confer risk of diabetes type 2 and cardiovascular disease. Body Mass Index (BMI) is predictive of metabolic syndrome. Previous research indicates that the BMI of incarcerated individuals not suffering from a major mental disorder increase during incarceration, especially amongst females. However, information on the development of BMI during forensic psychiatric care is scarcer, and follow-up periods have been short. Thus, the authors extracted data from the Swedish National Forensic Psychiatric Register regarding the longitudinal development of BMI in 3389 individuals who received court mandated forensic psychiatric care in Sweden during 2009-2020. A significant increase in BMI by 1.1% per year was observed during the first four years of care. After this, changes were no longer significant. Factors associated with a larger increase in BMI were female gender, being prescribed antipsychotics, young age at admission, receiving outpatient care, and access to an external support person. There was an inverse association between BMI and symptom severity. Substantial heterogeneity was observed in longitudinal changes in individual BMI and in comparisons between individuals receiving care at different clinics.

One premise for the organisation of residential care for youthis that staff are expected to relate to each young personindividually, but also to the group of young people as a whole.The relational interplay between staff and placed youths insecure unit care is fundamentally based on asymmetry, withinteractions taking place in a context of confinement. The aimhere is to explore how staff working in secure institutionalcare for youths in Sweden understand and describe theirrelationships with youth in terms that extend beyondprofessionalism, and especially their use of the familymetaphor. Fifty-three interviews with staff were analysed in atwo-step qualitative analysis, which generated three themesthat highlighted staff narratives focusing on descriptions ofparenting, sibling relationships, and closeness without usingthe family metaphor. One conclusion is that despite an overallshift away from the family metaphor, in the direction offraming residential care in professional terms, the familyconcept seems to sit quite well even in an environment withambitions to provide professional care. The family metaphormay not be the cornerstone of care, but it is eminentlypresent.

A key to the verification of nuclear weapon dismantling is the identification of presencerespectively absence of fissile materials in items, specifically weapons grade plutoniumand/or high enriched uranium. In the case of plutonium, spontaneous fission of minorityisotopes enables its detection through emitted neutrons, making passive use of neutrondetectors an attractive path. In the case of high enriched uranium, the emission ofspontaneous fission neutrons is negligible, making its detection difficult. However, usingactive interrogation where an external neutron source irradiates the item under investigation,induced fission neutrons are emitted from high enriched uranium as well as from weaponsgrade plutonium. Liquid organic scintillation detectors are a promising route to detect fissionneutrons for verification of nuclear disarmament. These detectors are sensitive to fastneutrons, which are characterized by low self-attenuation in most materials. In addition,while the detector is sensitive to gamma radiation, it can be effectively discriminated bypulse shape analysis. This work details the assessment of the applicability of a liquid organicscintillator for fast neutron detection for use in verification of nuclear weapon dismantling.The assessment was performed as a part of the BeCamp2 measurement campaignorganized by SCK-CEN, where a delegation from the Alva Myrdal Centre on NuclearDisarmament of Uppsala University participated. As a part of the campaign, 19 items withunknown content were assessed, with three different aims: template matching, determiningthe absence of nuclear material, and a technology challenge using active interrogation In thisfirst stage, where the content of the items is still not disclosed, it was concluded that theequipment was able to identify the presence of spontaneous fission content in items, usingpassive interrogation mode, within the measurement time constraints. Gamma and neutronspectrum comparison was a valuable tool for template m

Radionuclide monitoring is a proven means of non-intrusive verification of the nuclear test bantreaty. In addition to that, the potential use of radionuclide monitoring spans beyond thedetection of nuclear test explosions, since radionuclides can also be released and detected fromoperations of nuclear fuel cycle facilities, such as the reactor operation and nuclearreprocessing of plutonium production.In this work, we consider the use of coincidence and anticoincidence techniques as a means toincrease the sensitivity in radionuclide monitoring, in terms of improved minimum detectableamount for radionuclides of interest to filter stations used in radionuclide monitoring. Inparticular, a multi-detector setup is currently being prepared for the evaluation of the technique,and to provide validation data for a coincidence detector simulation codes.In this presentation, we will describe the multi-detector setup assembled for enabling theevaluation of various types of spectrometry, including 1) gamma-gamma coincidence (from dualdetectors and up to five High Purity Germanium (HPGe) detectors), 2) anticoincidence usingBGO active shield with single HPGe detector, as well as use of multiple detectors in add-backmode, i.e. simply using the combined detector volume for increased efficiency of single gammarays. We will present the results of measurements of a calibration sample, and provide adiscussion on the advantages and disadvantages of the tested techniques in the context ofradionuclide monitoring.

Since North Korea, or the Democratic People's Republic of Korea (DPRK) left the Non-Proliferation Treaty (NPT) in 2003, the DPRK nuclear fuel cycle has continued operation as well as further development, without transparency to international inspectors. A recent addition to the DPRK fuel cycle is the Experimental Light Water Reactor (ELWR), a 100 MWth light water reactor in Yongbyon, which, as appears to be in operation since October 2023. Considering the non-NPT-signatory status of DPRK, it is of concern that the ELWR may be used to produce plutonium for nuclear warheads, in addition to or instead of its use for electricity production. In this work we explore the possibility to model the fissile material production in the ELWR, by modelling the core with Serpent2, and integrating information from available remote monitoring, such as satellite imagery of cooling water outlets from the facility. Little openly available and verified information exists on the details of the ELWR, such as nuclear fuel design and core geometry. Therefore, a base case based on available statements is used to create a core model similar to conventional international LWRs. Multiple scenarios for core load options are based on either assumptions on 1) uniform enrichment optimised for low burnup and production of weapons-grade plutonium, 2) heterogeneous core with drivers of enrichment fuel and targets of natural uranium for plutonium production or 3) uniform enrichment for high burnup and electricity production. Plutonium production made possible using the ELWR is estimated per MWd, as well as per year of operation. Special consideration is given to cycle length constraints from requirement of weapons-grade quality of the produced plutonium, and implications on availability and stoppage frequency, which might be monitored remotely, unless online refuelling is a possibility. Possible implications on the DPRK Pu stockpile are discussed, as well as attempts to identify unknown parameters of imp

In the event of a far-reaching nuclear disarmament, nuclear weapon states would cease pro-duction of fissile materials for nuclear weapons, and also place their pre-existing plutonium andhigh enriched uranium (HEU) under international inspection. In this case, it can be anticipated that sizes of stockpiles are declared, with detailed records on how they were produced. Forexample, if the core geometry and operational history of a military reactor would be declaredby the owner state, the plutonium production of the core can be reconstructed using reactorphysics codes, which can provide confidence in the declared plutonium stockpiles.Challenges include that any data on fuel cycle operations provided by the state cannot beassumed to be truthful. This leads to the additional need to verify the declared operationalhistory by consistency checks within records and when possible with inspections. A further complication is that a long time might have passed since the fissile material production tookplace, and records can therefore be expected to be incomplete or inaccurate, and the responsiblepersonnel may be retired or even deceased. In this case, there may be a need to be able toreconstruct lost information on fuel cycle operations. We consider a test and training case of the Swedish pressurised heavy water reactor (PHWR) in Ågesta, which was in operation between 1963 and 1974. In this case study, we explore available archive material in order to obtain information such as the core loadings of the reactor, its operational history and the fuel designs used. Primarily we explore the use of records from the tritium monitoring for consistency checks with operational data records. Tritium production occurs via neutron capture in deuterium; a main component of heavy water, and since heavy water is an expensive asset, the consumption of it is closely monitored, for example by measuring tritium release. Moreover, the tritium production is proportional to the neutron flux in thereac

Publicerad på Östsällskapets hemsida 13 maj 2024.