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Targeted radiotherapy (TRT) is an increasingly prominent area of research in nuclear medicine, particularly in the context of treating cancerous tumors. One radionuclide of considerable interest for TRT is terbium-161 (t 1/2  = 6.95 days), which undergoes beta emission and shares similar decay properties as 177 Lu (FDA-approved as LUTATHERA® and PLUVICTO®). Besides beta emission, 161 Tb also emits a significant number of conversion and Auger electrons further enhancing its therapeutic potential. Terbium-161 can be produced using nuclear reactors through an indirect neutron capture reaction, G64160dn,γG64161d→3.66min,β - T65161b, from 160 Gd targets. However, a key challenge in utilizing 161 Tb for TRT lies in effectively separating target and product materials to attain high specific activity for radiolabeling. Here, we detail the production of no-carrier added 161 Tb using low flux research reactors (mean thermal (<0.625 eV) neutron flux: 1.356×10 12 n∙cm -2 ∙s -1 ) like the University of Utah TRIGA Reactor, using enriched 160 Gd 2 O 3 targets (1.5 ± 0.3 μCi of 161 Tb per mg of 160 Gd target per hour of irradiation). We also developed a separation technique based on cation exchange and extraction chromatography, suitable for mCi level irradiations with targets exceeding 200 mg. In a simulated full-scale irradiation, 161 Tb was successfully isolated from large mass targets using cation exchange (AG 50W-X8, with 2-hydroxyisobutyric acid at 70 mM, pH 4.75) and extraction chromatography (LN Resin, 0.5-0.75 M HNO 3 ) methods. This resulted in high apparent molar activities of [ 161 Tb]Tb-DOTA (113 ± 3 MBq/nmol), demonstrating high purity 161 Tb relevant for potential future preclinical applications., Competing Interests: Declaration of competing interest The authors declare the following financial interests/personal relationships which may be considered as potential competing interests: Tara Mastren reports financial support was provided by U.S.Department of Energy. If there are other authors, they declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier Ltd. All rights reserved.)

Two commercially available extraction chromatography (EXC) resins containing N,N,N',N'-tetra-n-octyldiglycolamide (DGA Resin, Normal, 50 - 100 μm) and Bis(2-ethylhexyl) phosphate (LN Resin, 100 - 150 μm) were used as adsorbents to study fundamental adsorption properties such as thermodynamic values, equilibrium isotherms, and kinetic uptake models for terbium(III) adsorption. Weight distribution ratios (D w ) for terbium on DGA and LN resins were measured using a [ 160 Tb]Tb 3+ radiometric tracer in nitric acid as a function of acidity, temperature, initial analyte concentration, and equilibrium time. The D w values showed increasing binding affinity for DGA resin at high nitric acid concentrations and decreasing binding affinity for LN resins. Thermodynamic studies for DGA and LN resins revealed that the Gibbs free energy (ΔG) increased consistently with temperature. To model equilibrium data, increasingly higher parameter equilibrium isotherm models (Henry (1) < Langmuir, Freundlich (2) < Redlich-Peterson (3) < Fritz-Schluender (4)) were compared on their root mean squared errors (RMSE) and adjusted determination coefficients to determine the most applicable model. In all cases, the empirical four-parameter Fritz-Schluender isotherm demonstrated a superior fit. Similar comparisons for reaction-based kinetic models (Pseudo-first-order < Pseudo-second-order < Pseudo-n-order) revealed that the higher-order PNO model yielded a superior fit of kinetic data for both resins. However, in some cases, adsorption isotherms and kinetic models could also be modeled by a lower-order model with minimal change in error parameters. Weber-Morris plots revealed that two linear sections are observed for each resin, where the first linear segment is attributed to fast (film diffusion) adsorption of terbium, followed by slower intraparticle diffusion of terbium through the pores as the rate-limiting step. Based on the Weber-Morris plot, both film and intraparticle diffusion are involved in controlling the kinetic rate of adsorption for DGA and LN resins., Competing Interests: Declaration of competing interest The authors declare the following financial interests/personal relationships which may be considered as potential competing interests: Tara Mastren reports financial support was provided by Department of Energy. If there are other authors, they declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier B.V. All rights reserved.)

Research has demonstrated links from early childhood shyness to socioemotional problems later in life. This longitudinal study explored the role of early social play behaviors and language skills in the associations between childhood shyness and later internalizing and language difficulties in school. Participants were N = 7,447 children (50.1% girls) from the Norwegian Mother, Father, and Child Cohort Study (MoBa). Latent direct, indirect, and interaction path analyses were performed within a structural equation framework. Results showed that mother-rated childhood shyness from age 18 months to age five years was associated with mother-rated internalizing difficulties and language problems at age eight years. Lower levels of teacher-reported social play behaviors and poorer language skills in preschool increased the risk of later anxiety problems among shy children, whereas higher levels of language competencies and social play behaviors buffered against later anxiety problems. The study identifies some of the early risk and protective factors that may influence shy children's socio-emotional functioning and adjustment., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2023 Baardstu, Sette, Brandlistuen and Wang.)

Background: Children with poor motor skills are at increased risk of peer victimization. However, it is unclear whether poor gross and fine motor skills are differently linked to peer victimization among pre-school and schoolchildren., Aims: To investigate associations between poor gross and fine motor skills measured in pre-school and the associations to peer victimization measured concurrently and in school age., Sample: Data from the Norwegian Mother, Father and Child Cohort Study (MoBa), and the Medical Birth Registry of Norway were used. Participants with complete questionnaires at 3, 5, and 8 years (n = 23 215) were included., Methods: A longitudinal design and an autoregressive cross-lagged model were used to investigate if poor gross and fine motor skills at 3 and 5 years predicted peer victimization at 5 and 8 years. Because emotional difficulties are associated with both motor skills and peer victimization, the results were adjusted for emotional difficulties., Results: Only poor fine motor skills at 3 years had a significant association to peer victimization at 5 years. Poor gross motor skills at 5 years had a stronger association to peer victimization measured concurrently compared to poor fine motor skills, and only poor fine motor skills at 5 years was significantly linked to peer victimization at 8 years. No gender difference was found between these paths., Conclusions: Teachers and parents should be aware that motor skills predict peer victimization, and that poor gross and fine motor skills have different associations to peer victimization measured at different ages., (© 2021 The Authors. British Journal of Educational Psychology published by John Wiley & Sons Ltd on behalf of British Psychological Society.)

Here we present a new method of irradiating 134 Xe capsules to produce 135 Xe gas standards which maximize the ratio of 135 Xe to 133 Xe production due to (n,g) and (n,2n) reactions, respectively. We performed "Spectral tuning" of the University of Utah TRIGA Reactor (UUTR) neutron spectrum to increase the length of time that 135 Xe dominates undesirable 135 Xe in the sample, so that the capsules - used for calibration and quality control testing of Xe gas detection equipment in support of the Comprehensive Test Ban Treaty (CTBT) - will remain viable for longer periods post-irradiation. Moreover, optimized methods of computation and analysis were developed yielding improved computational efficiency over standard Monte Carlo approaches. These methods provided valuable insight into the final design and manufacture of new, ex-core Teflon irradiation chambers tested in the UUTR. The methods of computation and analysis, as well as the physical irradiation chamber designs, were derived such that they could be readily applied to any reactor for spectral tuning of a specific reactor's flux profile. Results of the physical experiments employing the optimized irradiation chamber designs demonstrated sample viability time improvements of over 60% when compared to conventional, un-optimized methods of gas sample generation. Thus, use of these methods enhance both the CTBT-related calibrations and performance testing, and the continued stability of the CTBT monitoring network overall., (Copyright © 2022 Elsevier Ltd. All rights reserved.)

Objectives: To test the feasibility and preliminary effectiveness of the NIATx model for organizational change to reduce appointment no-shows in dental care settings., Methods: The NIATx Dental Pilot Study used a clustered prepost interventional design and a mixed-methods approach. Five independent dental clinics serving Medicaid enrollees were recruited. Quantitative data on the impact of the NIATx model were complemented by qualitative assessment information collected from dental staff. The NIATx model was applied through a multisite learning collaborative that engaged participating organizations in adopting targeted no-show best practices. The primary outcome measure was no-show data collected at the preintervention phase (5 months), intervention phase (7 months), and postintervention phase (3 months)., Results: Female patients were in the majority (median 54.5 percent). Mean age ranged from 8 to 50 (median 35.2) years. The median percentage for Hispanics was 11.0 percent, and the proportion of uninsured patients was 25 percent. Preintervention no-show rates ranged from 14 percent (clinic B) to 38 percent (clinic E). All clinics had lower no-show rates during the postintervention period, with decreases ranging from 1 percent (clinic B) to 13 percent (clinic E). Overall, the no-show rates decreased in the study., Conclusions: The study demonstrated the feasibility of applying the NIATx model to reduce no-show rates, with some difficulty observed with sustainability across dental practices during the postintervention period., (© 2021 American Association of Public Health Dentistry.)

Background and Purpose Schoolchildren with language difficulties experience more peer victimization compared to their typically developing (TD) peers. Whether these children also bully their peers (bully perpetration) more than TD children is unclear. Furthermore, little is known about peer victimization and bully perpetration among preschool children with language difficulties and how it may be related to different paths of language difficulties. This study aimed to investigate associations between language difficulties, peer victimization, and bully perpetration from preschool to school age as well as the risk of peer victimization and bully perpetration for children with different developmental paths of language difficulties and mild language difficulties compared to TD children. Method The sample was drawn from the Norwegian Mother, Father and Child Cohort Study. Participants with completed questionnaires at 3, 5, and 8 years of age ( n = 22,628) were included. Paths between latent variables of language skills at 3, 5, and 8 years of age, peer victimization at 5 and 8 years of age, and bully perpetration at 8 years of age were examined with structural equation modeling. Logistic regression was used to investigate peer victimization and bully perpetration for predefined paths of language difficulties. Results Poor language skills at 3 and 5 years of age were associated with peer victimization at 5 years of age. Poor language skills at 5 and 8 years of age were associated with peer victimization and bully perpetration at 8 years of age. The association between poor language skills at 5 years of age and bully perpetration at 8 years of age was stronger for girls. Persistent paths of language difficulties at 3, 5, and 8 years of age showed the highest risk of peer victimization and bully perpetration. Conclusions Language difficulties are associated with peer victimization and bully perpetration. The risk of peer victimization and bully perpetration differs according to different developmental paths of language difficulties from preschool to school age.

Background: Female educational advantage is evident from elementary school and throughout the education system. Understanding the gender differences that precede school entry might provide important insight as to why girls outperform boys later in their educational careers. Aims: The aim of this study was to explore gender differences in early literacy and numeracy skills, as well as a range of neurodevelopmental and behavioral domains between the age of five and six years. Methods: We used questionnaire data from preschool teachers in the Norwegian Mother, Father and Child Cohort Study reported for 7467 children attending the final year in preschool, to explore gender differences and age patterns by fitting flexible regression models predicting pre-academic, behavioral and neurodevelopmental outcomes. Results: We found gender differences favoring girls for all outcomes except internalizing behavior. For neurodevelopment and behavior, differences in adjusted standardized scores ranged from 46% of a standard deviation (95% confidence interval (CI) 0.41, 0.50) in overall school readiness to 31% of a standard deviation difference in externalizing behavior problems (CI 0.21, 0.41). We found gender differences for all literacy skills in favor of girls. The gender gap in naming and adding numbers was small, but in favor of girls. Increasing age was associated with improved pre-academic skills and school readiness, as well as reduction of attention problems and language difficulties, the latter especially for boys. Conclusions: We conclude that gender differences favoring girls exist prior to school entry for a broad range of pre-academic, behavioral and neurodevelopmental skills relevant to school functioning.

Purpose This article explored the predictive values of three main language delay (LD) trajectories (i.e., persistent, late onset, and transient) across 3-5 years on poor literacy at 8 years. Additionally, the effect of gender was assessed, using both gender-neutral and gender-specific thresholds. Method The data comprised mother-reported questionnaire data for 8,371 children in the Norwegian Mother, Father, and Child Cohort Study. Analyses were conducted using binary logistic regression in SPSS to make predictions about risk. Results LD reported at preschool age was associated with excess risk of poor literacy at 8 years with odds ratios ranging from 3.19 to 9.75 dependent on trajectory, persistent LD being the strongest predictor. The odds ratio of transient LD was similar to that of late-onset LD. Gender was not found to play an important role in the association between oral language and literacy, as the gender difference disappeared when gender-specific deficit criterion was used. Conclusion Our study supports the longitudinal association between preschool oral language and school-aged literacy skills and highlights the importance of different LD trajectories across preschool ages in predicting later literacy. Furthermore, practitioners are recommended to consider gender-specific cutoffs in relation to language and literacy measures.

Objective: The aim is to investigate if young children with developmental and behavioral difficulties (DBDs) have greater risk of peer-victimization compared with typically developing (TD) children., Method: The sample was drawn from the Norwegian Mother and Child Cohort Study (MoBa). MoBa has collected population-based data on children's health and development for 114,500 children. We included children that were 5 years of age (n = 41,609). Multivariate logistic regression was used to estimate the effect of different DBDs and of co-occurring DBDs on peer-victimization compared with TD children. Categories of DBDs included autistic traits, emotional difficulties, behavioral difficulties, general learning difficulties, attention difficulties/impulsive behavior, motor development difficulties, language difficulties, and hearing and vision difficulties. Results were adjusted for socioeconomic status and the child's sex., Results: Peer-victimization was 2.8% (933) among TD children, and 8.0% (615) among children with DBD. The highest risk of peer-victimization was found among children with autistic traits and children with five or more co-occurring DBDs (adjusted odds ratios [ORs] = 12.76; 95% confidence interval [CI] 8.64-18.84; p ≤ .001) and 17.37 (95% CI 12.15-24.82; p ≤ .001)], respectively. The lowest risk was found among children with hearing and vision difficulties and children with only one DBD [adjusted ORs = 1.98 (95% CI 1.71-2.29; p ≤ .001) and 1.95 (95% CI 1.70-2.22; p ≤ .001)]., Conclusion: Children with DBD have a substantially higher risk of peer-victimization compared with TD children. Peer-victimization varies with type of DBD and increases cumulatively by number of DBDs., (© The Author(s) 2019. Published by Oxford University Press on behalf of the Society of Pediatric Psychology. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.)

Studies have shown that early language difficulties are associated with later internalizing problems. Less is known about the nature of the association: the bidirectional relationship over time, the role of different types of language difficulties, and gender differences. The present study examined bidirectional longitudinal associations between parent-rated language difficulties and internalizing problems in a four-wave cross-lagged model from 18 months to 8 years. Data from the Norwegian Mother and Child Cohort Study were used (N = 114,000). Gender-specific dichotomized language variables were created, and associations were investigated uniquely for boys and girls. Logistic regression analyses showed that all cross-lagged associations from 18 months to 5 years were significant for girls (odds ratios [ORs] = 1.48-1.94). For boys, only internalizing problems at 3 years predicted change in language difficulties (OR = 2.33). From 5 to 8 years, the cross-lagged associations between semantic language difficulties and internalizing problems were significant and strong for girls (ORs = 1.92-2.97) and nonsignificant for boys. The results suggest that the associations between language difficulties and internalizing problems are bidirectional from an early age, and that girls are especially vulnerable for developing co-occurring language difficulties and internalizing problems during the years of transition to school.

This study sought to examine the direction of causation between language delay and two externalizing problems; inattention and aggression. Autoregressive fixed effects models were fitted to data from 25,474 children (age 1.5 to 5 years; 50.8% boys) in the population-based longitudinal Norwegian Mother and Child Cohort Study (MoBa), to model the direction of causality for language delay and inattention and aggression, respectively. The most parsimonious model for the relationship between language delay and inattention was one where both common factors and reciprocal causation were estimated. Adjusted for common factors, language delay was estimated to have a non-significant effect on inattention by b = 0.12 (p = 0.06), and inattention to have a significant effect on language delay by b = 0.19 (p = 0.03). The most parsimonious model for the direction of causality for language delay and aggression was one where the entire association could be explained by language delay having effect on aggression b = 0.12 (p < 0.02). It appears that while language delay can best be conceptualized as an epiphenomenon of inattention partly related to both common factors and causal processes, aggression can best be conceptualized as caused by language delay. This illumination of the hypothetical causal links between two common problem domains in preschool-aged children has clear implications on where to implement interventions to prevent co-occurrence of language delay and externalizing problems.

Background: Communicative and motor development is frequently found to be associated. In the current study we investigate to what extent communication and motor skills at 1½ years predict skills in the same domains at 3 years of age., Methods: This study is based on the Norwegian Mother and Child Cohort Study (MoBa) conducted by the Norwegian Institute of Public Heath. Data stem from 62,944 children and their mothers. Mothers completed questionnaires on their child's communication and motor skills at ages 1½ and 3. Associations between communication and motor skills were estimated in a cross-lagged model with latent variables., Results: Early communication skills were correlated with early motor skills (0.72). Stability was high (0.81) across time points for motor skills and somewhat lower (0.40) for communication skills. Early motor skills predicted later communication skills (0.38) whereas early communication skills negatively predicted later motor skills (-0.14)., Conclusion: Our findings provide support for the hypothesis that these two difficulties are not symptoms of separate disorders, but might rather be different manifestations of a common underlying neurodevelopmental weakness. However, there also seem to be specific developmental pathways for each domain. Besides theoretical interest, more knowledge about the relationship between these early skills might shed light upon early intervention strategies and preventive efforts commonly used with children with problems in these areas. Our findings suggest that the relationship between language and motor skills is not likely to be simple and directional but rather to be complex and multifaceted., (© 2012 John Wiley & Sons Ltd.)