Paths to Positivity: Relational Trajectories and Interaction in Positive Stepparent-Stepchild Dyads

Stepfamilies are inherently complex family systems, marked by change, flexible boundaries, and early conflict. But the developmental pathways by which long-term stepparent relationships become positive require more study. We interviewed 38 stepchildren who had reached adulthood, to understand how their relationships with a stepparent became positive. Four relational trajectories defined these positive relationships: punctuated, consistent positive, progressive incline, and modulated turbulent. Distinctive communicative practices were associated with each trajectory, such as communicating assurances, “siding,” or revelations of character. In addition, the trajectories shared three common processes: responsiveness to stepchild vulnerability, stepparent “adding value” to the family, and maturation/ reframing of the past. Findings support the existence of multiple pathways to positivity and suggest that major fluctuations are experienced along the way. Findings are interpreted in light of existing research on stepfamily development and Afifi’s theory of resilience and relational load. Recommendations are offered for stepfamilies and professionals who serve them

The Interpersonal Style and Complementarity Between Crisis Negotiators and Forensic Inpatients

Previous negotiation research has explored the interaction and communication between crisis negotiators and perpetrators. A crisis negotiator attempts to resolve a critical incident through negotiation with an individual, or group of persons in crisis. The purpose of this study was to establish the interpersonal style of crisis negotiators and complementarity of the interpersonal interaction between them and forensic inpatients. Crisis negotiators, clinical workers and students (n = 90) used the Check List of Interpersonal Transactions-Revised (CLOIT-R) to identify interpersonal style, along with eight vignettes detailing interpersonal styles. Crisis negotiators were most likely to have a friendly interpersonal style compared to the other non-trained groups. Complementarity theory was not exclusively supported as submissive individuals did not show optimistic judgments in working with dominant forensic inpatients and vice versa. Exploratory analysis revealed that dominant crisis negotiators were optimistic in working with forensic inpatients with a dominant interpersonal style. This study provides insight into the area of interpersonal complementarity of crisis negotiators and forensic inpatients. Whilst further research is required, a potential new finding was established, with significant ‘similarity’ found when dominant crisis negotiators are asked to work with dominant forensic inpatients

Telomere lengths in human oocytes, cleavage stage embryos and blastocysts

Telomeres are repeated sequences that protect the ends of chromosomes and harbour DNA-repair proteins. Telomeres shorten during each cell division in the absence of telomerase. When telomere length becomes critically short, cell senescence occurs. Telomere length therefore reflects both cellular ageing and capacity for division. We have measured telomere length in human germinal vesicle (GV) oocytes and pre-implantation embryos, by quantitative fluorescence in-situ hybridisation (Q-FISH), providing baseline data towards our hypothesis that telomere length is a marker of embryo quality. The numbers of fluorescent foci suggest that extensive clustering of telomeres occurs in mature GV stage oocytes, and in pre-implantation embryos. When calculating average telomere length by assuming that each signal presents one telomere, the calculated telomere length decreased from the oocyte to the cleavage stages, and increased between the cleavage stages and the blastocyst (11.12 vs 8.43 vs 12.22kb respectively, p<0.001). Other methods of calculation, based upon expected maximum and minimum numbers of telomeres, confirm that telomere length in blastocysts is significantly longer than cleavage stages. Individual blastomeres within an embryo showed substantial variation in calculated average telomere length. This study implies that telomere length changes according to the stage of pre-implantation embryo development

Review of zirconolite crystal chemistry and aqueous durability

Zirconolite (CaZrTi2O7) has been identified as a candidate ceramic wasteform for the immobilisation and disposal of Pu inventories, for which there is no foreseen future use. Here, we provide an overview of relevant zirconolite solid solution chemistry with respect to Ce, U and Pu incorporation, alongside a summary of the available literature on zirconolite aqueous durability. The zirconolite phase may accommodate a wide variety of tri- and tetravalent actinide and rare-earth dopants through isovalent and heterovalent solid solution, e.g. CaZr1–xPuxTi2O7 or Ca1–xPuxZrTi2–2xFe2xO7. The progressive incorporation of actinides within the zirconolite-2M parent structure is accommodated through the formation of zirconolite polytypoids, such as zirconolite-4M or 3T, depending on the choice of substitution regime and processing route. A variety of standardised durability tests have demonstrated that the zirconolite phase exhibits exceptional chemical durability, with release rates of constituent elements typically <10−5 gm−2·d−1. Further work is required to understand the extent to which polytype formation and surrogate choice influence the dissolution behaviour of zirconolite wasteforms

A disposal-MOX concept for plutonium disposition

In case it is desirable to dispose of inventories of separated civil PuO2 that have no further use, a suitable immobilisation matrix is required, prior to disposition in a geological disposal facility. Conversion of Pu into a mixed oxide (MOX)-type material with characteristics suitable for disposal has previously been suggested, but not yet demonstrated at laboratory or industrial scale. We here demonstrate the feasibility of different synthesis routes for simulant “disposal-MOX”, using Th4+ as a Pu4+ surrogate and containing Gd3+ in a suitable quantity to ensure criticality control. Compositions of (U(1−(x+y))ThxGdy)O2−δ, where x = 0.1, 0.2 and x : y = 10 : 1 or 100 : 1, were synthesised by a solid state route mimicking the industrial MIMAS (MIcronized MASterblend) MOX fuel fabrication process, or through an oxalic wet co-precipitation method. Both synthesis routes gave a single phase fluorite structure upon heat-treatment at 1700 °C, with a grain size similar to (Pu,U)O2 MOX fuel. The relative density of the sintered pellets was >90% but was highest in co-precipitated materials, with Th4+ and Gd3+ additions more homogenously distributed. Though no unincorporated ThO2 or Gd2O3 was observed in any sample, Th and Gd-rich regions were more prevalent in materials produced through solid state synthesis, in accordance with MIMAS MOX fuel microstructures. The incorporation of Gd3+ within the fluorite lattice, which is favourable from a criticality control perspective in a Pu wasteform, was found to be charge balanced via the generation of oxygen vacancy defects, but not U5+. These results demonstrate feasible synthesis routes for a disposal-MOX wasteform product via both solid state and wet co-precipitation fabrication routes

Identifying patterns of communication in patients attending memory clinics: a systematic review of observations and signs with potential diagnostic utility

Background Subjective cognitive complaints are commonly encountered in primary care and often result in memory clinic referral. However, meta-analyses have shown that such concerns do not consistently correspond to objective memory impairment or predict future dementia. Memory clinic referrals are increasing, with greater proportions of patients attending who do not have dementia. Studies of interaction during memory clinic assessments have identified conversational profiles that can differentiate between dementia and functional disorders of memory. To date, studies exploring communication patterns for the purpose of diagnosis have not been reviewed. Such profiles could reduce unnecessary investigations in patients without dementia. Aim To identify and collate signs and observable features of communication, which could clinically differentiate between dementia and functional disorders of memory. Design and setting This was a systematic review and synthesis of evidence from studies with heterogeneous methodologies. Method A qualitative, narrative description and typical memory clinic assessment were employed as a framework. Results Sixteen studies met the criteria for selection. Two overarching themes emerged: 1) observable clues to incapacity and cognitive impairment during routine assessment and interaction, and 2) strategies and accounts for loss of abilities in people with dementia. Conclusion Whether the patient attends with a companion, how they participate, give autobiographical history, demonstrate working memory, and make qualitative observations during routine cognitive testing are all useful in building a diagnostic picture. Future studies should explore these phenomena in larger populations, over longer periods, include dementia subtypes, and develop robust definitions of functional memory disorders to facilitate comparison

High-Speed Energy-Resolved STJ Photometry of the Eclipsing Binary UZ For

We present high time-resolution optical photometry of the eclipsing binary UZ For using a superconducting tunnel junction (STJ) device, a photon-counting array detector with intrinsic energy resolution. Three eclipses of the $\sim$18 mag 126.5 min orbital binary were observed using a $6\times6$ array of Tantalum STJs at the 4.2-m William Herschel Telescope on La Palma. The detector presently provides individual photon arrival time accuracy to about 5 $\mu$s, and a wavelength resolution of about 60 nm at 500 nm, with each array element capable of counting up to $\sim$5000 photons s$^{-1}$. The data allow us to place accurate constraints on the accretion geometry from our time- and spectrally-resolved monitoring, especially of the eclipse ingress and egress. We find that there are two small accretion regions, located close to the poles of the white dwarf. The positions of these are accurately constrained, and show little movement from eclipse to eclipse, even over a number of years. The colour of the emission from the two regions appears similar, although their X-ray properties are known to be significantly different: we argue that the usual accretion shock may be absent at the non-X-ray emitting region, and instead the flow here interacts directly with the white dwarf surface; alternatively, a special grazing occultation of this region is required. There is no evidence for any quasi-periodic oscillations on time-scales of the order of seconds, consistent with relatively stable cyclotron cooling in each accretion region.Comment: Accepted by MNRAS: 11 pages, 8 figure

Thermal treatment of nuclear fuel-containing Magnox sludge radioactive waste

Magnesium aluminosilicate and magnesium borosilicate glass formulations were developed and evaluated for the immobilisation of the radioactive waste known as Magnox sludge. Glass compositions were synthesised using two simplified bounding waste simulants, including corroded and metallic uranium and magnesium at waste loadings of up to 50 wt.%. The glasses immobilising corroded simulant waste formed heterogeneous and fully amorphous glasses, while those immobilising metallic wastes contained crystallites of UO2 and U3O8. Uranium speciation within the glass was investigated by micro-focus X-ray absorption near edge spectroscopy and it was shown that the borosilicate glass compositions were characterised by a slightly lower mean uranium oxidation state than the aluminosilicate counterparts. This had an impact upon the durability, and uranium within glasses of higher mean oxidation states was dissolved more readily. All material showed dissolution rates that were comparable to simulant high level radioactive waste glasses, while the borosilicate-based formulations melted at a temperature suitable for modern vitrification technologies used in radioactive waste applications. These data highlights the potential for vitrification of hazardous radioactive Magnox sludge waste in borosilicate or aluminosilicate glass formulations, with the potential to achieve >95 % reduction in conditioned waste volume over the current baseline plan