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The present work concerns the development of a technique for activity determination of 68Ge/68Ga and 57Co disused radioactive sources. This technique aims to determine the activity of these sources by measuring and Monte Carlo simulation using the MCNPX code. Therefore, efficiency calibrations of the 3 x 3 NaI(Tl) detector for specific source geometries were carried out. Spectrums for two types of disused radioactive sources were collected for different measurement times. The characteristic gamma rays of a flood source containing 57Co and a line source containing 68Ge/68Ga, were used. In case of 68Ge/68Ga, the annihilation peak of 511 keV was also used considering the disused radioactive sources as a positron emitter. Sources of the mentioned types with certified nominal activities were used to validate MCNPX models. For the 57Co source, 15 minutes measuring time was adequate for activity determination, and 2 hours measuring time provided adequate sensitivity, at the level of general clearance. For 68Ge/68Ga line source, 15 minutes measurement was adequate for activity determination by using the 511 keV from the annihilation of 1899.1 keV positrons.

Hematologic toxicity is a common side effect of multimodal cancer therapy. Nearly all animal studies investigating the causes of radiotherapy-induced hematologic toxicity use inbred strains with limited genetic diversity and do not reflect the diverse responses observed in humans. We used the population-based Collaborative Cross (CC) mouse resource to investigate the genetic architecture of the acute and persistent immune response after radiation exposure by measuring 22 immune parameters in 1,720 CC mice representing 35 strains. We determined relative acute and persistent radiation resistance scores at the individual strain level considering contributions from all immune parameters. Genome-wide association analysis identified quantitative trait loci associated with baseline and radiation responses. A cross-species radiation resistance score predicted recurrence-free survival in medulloblastoma patients. We present a community resource of immune parameters and genome-wide association analyses before and after radiation exposure for future investigations of the contributions of host genetics on radiosensitivity.

The concept of 'pedagogic voice' emphasises the capacity of children to express their views on matters related to teaching, learning and curriculum. 'Pedagogic voice' aligns with children's rights to be listened to and the extent to which their views are fully considered and acted upon. Combined, these rights based approaches positively shape children's learning experiences. This paper draws on quantitative and qualitative data from the longitudinal mixed methods cohort study Children's School Lives to explore children's voice. Grounded in the sociology of pedagogic voice literature and building upon research on children's participatory rights, the paper explores children's experiences of being heard and actively participating in decision-making processes in diverse primary school settings in Ireland. It analyses children's voice by looking at their capacity to influence their own learning, contrasting their experiences and perspectives, to those of their teachers. Findings illustrate the interplay between children's and teachers' narratives regarding children's voice and their pedagogical encounters to explore the impact on teaching and learning processes, highlighting structural challenges to the realisation of children's voice in primary classrooms in Ireland.

The carbonation reaction is essential in the global carbon cycle and in the carbon dioxide (CO2) capture. In oceans (pH 8.1) or in synthetic materials such as cement or geopolymers (pH over 12), the basic pH conditions affect the reaction rate of carbonation. However, the precipitation of calcium or magnesium carbonates acidifies the environment and, therefore, limits further CO2 capture. Here, we investigate how pH influences carbonation pathways in neutral and basic solutions at the atomic scale using reactive molecular simulations coupled with enhanced sampling methods from CO2 to calcium carbonate (CaCO3). Two distinct CO2 conversion pathways are identified: (1) CO2 hydration: CO 2 + H 2 O ⇌ H 2 CO 3 ⇌ HCO 3 − + H + ⇌ CO 3 2 − + 2 H + and (2) CO2 hydroxylation: CO 2 + OH − ⇌ HCO 3 − ⇌ CO 3 2 − + H + . The CO2 hydration pathway occurs in both neutral and basic aqueous solutions, but reactions differ significantly between the two pH conditions. The formation of the CO 3 2 − is characterized by a markedly high free energy barrier in the neutral solution. The CO2 hydroxylation pathway is only found in basic solutions. Notably, the CO2 molecule exhibits a pronounced energetic preference for reacting with hydroxide ions (OH−) rather than with water molecules, resulting in significantly reduced free energy barriers along the CO2 hydroxylation pathway. The reaction rate estimation suggests that the CO2 hydroxylation path is the most favorable carbonation pathway in the basic solution. Once the CO 3 2 − anion is formed in the presence of alkali-earth (e.g., Ca2+ and Mg2+) cations, carbonate formation can proceed. [ABSTRACT FROM AUTHOR]

Rheumatoid arthritis (RA) is a well-known autoimmune inflammatory disease that affects the diarthrodial joints. Inflammation increases the production of reactive oxygen species (ROS), which may explain why RA is one of the diseases that induce oxidative stress. This study aimed to evaluate the potential differences in biochemical, hematological, and oxidative stress markers in the early stages of RA and after different treatment regimens. The study involved 111 patients, 28 men and 83 women aged 34 to 59 years, who were divided based on their c-reactive protein (CRP) levels into inactive RA patients (IRA) with CRP < 1.3 (n = 57, 22 men and 35 women) and active RA patients (ARA) with CRP ≥ 1.3 (n = 54, 6 men and 48 women). The study participants were divided into two groups, A and B, based on their treatment regimen. Group A, 90% of which were IRA patients, received methotrexate (MTX) monotherapy. Group B, which comprised 90% ARA patients, received a combination of leflunomide, a conventional disease-modifying antirheumatic drug (DMARD), and a biologic DMARD. The hematological, biochemical, oxidative stress, and RA-specific biomarkers were measured twice in groups A and B in the early stage of the disease, before and 3 months post-treatment, using conventional colorimetric, fluorometric, and immunological assays. According to the results of our study, glutathione peroxidase (GPx), ROS, calcium (Ca) and phosphorus (P) ions, vitamin C and D, and lipid profiles could serve as potential diagnostic markers in the early stages of the disease. Both treatment options were equally effective at improving the overall health of the patients. However, treatment resulted in a further increase in ROS levels and a decrease in antioxidant markers.

Background: Menopause has a significant impact on the endocrine system of middle-aged women, resulting in a loss of skeletal muscle mass (SMM), changes in fat mass (FM) and a reduction in strength capacity. Resistance training (RT) and a high-protein diet (HPD) are effective methods for maintaining or increasing SMM. This study aims to determine the effects of HPD and RT on body composition, muscle thickness and strength capacity in postmenopausal women. Methods: In total 55 healthy postmenopausal women (age: 58.2 ± 5.6 years, weight 69.1 ± 9.6 kg, height 166.5 ± 6.5 cm) successfully participated in the study. The women were randomly assigned to either group: training + protein (2.5 g/kg fat-free mass (FFM)) (n = 15; TP); only training (n = 12; T); only protein (2.5 g/kg FFM) (n = 14; CP) or control (n = 14; C). TP and T performed RT for 12 weeks with three training sessions and five exercises each. CP and C were prohibited from training during the period. The main parameters analysed for body composition were FFM, SMM, FM, muscle thickness of the M. rectus femoris, M. biceps femoris, M. triceps brachii and M. biceps brachii muscles. Strength was tested using a dynamometer for grip strength and 1-RM in the squat (BBS) and deadlift (DL). Results: The SMM significantly increased by RT (TP: (Δ+1.4 ± 0.9 kg; p < 0.05; d = 0.4; T: Δ+1.2 ± 1.3kg; p < 0.05; d = 0.3) and FM could be reduced only in T: (Δ−2.4 ± 2.9 kg; p < 0.05; d = 0.3). In muscle thickness a significant increase in the M. biceps brachii in both training groups (TP: (Δ+0.4 ± 0.3 cm; p < 0.05; d = 1.6; T: (Δ+0.3 ± 0.3 cm; p < 0.05; d = 0.9) and in M. biceps femoris only in TP (Δ+0.3 ± 0.4 cm; p < 0.05; d = 0.9) were observed. HPD without training does not affect body composition, A significant increase in grip strength (TP: Δ+4.7 ± 2.4 kg; (p < 0.05; d = 1.5; T: (Δ+3.6 ± 3.0 kg; p < 0.05; d = 0.8), in BBS (TP: (Δ+30.0 ± 14.2 kg; p < 0.05; d = 1.5; T: (Δ+34.0 ± 12.0 kg; p < 0.05; d = 2.4) and in DL (TP: (Δ+20.8 ± 10.3 kg; p < 0.05; d = 1.6; T: (Δ+22.1 ± 7.6 kg; p < 0.05; d = 2.0) was observed in both training groups. The CP also recorded a significant increase in the BBS (Δ+7.5 ± 5.4 kg; p < 0.05; d = 0.4) and in DL (Δ+5.5 ± 7.7 kg; p < 0.05; d = 0.5). No significant differences were detected for TP and T for any of the parameters. Conclusion: The results indicate that RT enhances body composition and strength capacity in postmenopausal women and is a preventive strategy against muscle atrophy. Besides HPD without training has a trivial significant effect on BBS and DL. HPD with RT has no clear additive effect on body composition and strength capacity. Further studies are needed to confirm these observations.

IntroductionNew onset refractory status epilepticus (NORSE) is a rare and devastating condition characterised by the sudden onset of refractory status epilepticus (RSE) without an identifiable acute or active structural, toxic, or metabolic cause in an individual without a pre-existing diagnosis of epilepsy. Febrile infection-related epilepsy syndrome (FIRES) is considered a subcategory of NORSE and presents following a febrile illness prior to seizure onset. NORSE/FIRES is associated with high morbidity and mortality in children and adults.Methods and resultsIn this review we first briefly summarise the reported clinical, paraclinical, treatment and outcome data in the literature. We then report on existing knowledge of the underlying pathophysiology in relation to in vitro and in vivo pre-clinical seizure and epilepsy models of potential relevance to NORSE/FIRES.DiscussionWe highlight how pre-clinical models can enhance our understanding of FIRES/NORSE and propose future directions for research.

Background: The paper discusses how the design of summative assessments of practical science can be enhanced through the use of robust theoretical models that capture the diversity of scientific methods. The developments in assessment policy in England and the role of practical science in teaching and learning of science are reviewed. Purpose: The paper has two main purposes: (a) to explore how summative assessments of practical science can potentially reflect the breadth of scientific methods; and (b) to investigate how Year 10 students in England engage with and perceive summative assessments designed using Brandon's Matrix, a framework clarifying the diversity of scientific methods. Sample: The paper draws on data from Year 10 (14-15 years old) students with a sample of physics assessment tasks developed using Brandon's Matrix. Design and methods: The study focused on the development of a series of assessment questions based on Brandon's Matrix, a framework by a philosopher of science, who classifies scientific methods in a taxonomy. Students' performance on the assessments as well as their perceptions about practical science are investigated. Conclusion: The results suggest that students held a very narrow understanding of what a scientific method is and often linked it to hypothesis testing, variable manipulation and measurement of several variables. Furthermore, they reported not to enjoy drawing conclusions from data.

Research indicates that teachers lack a sophisticated understanding of Nature of Science (NOS), which in turn, can impact their instructional decisions and students' understanding of NOS. The aim of the study was to investigate United Arab Emirates (UAE) early years' science teacher's (N = 433) perceptions about the NOS. Results obtained from a 70-item questionnaire revealed that teachers have an adequate understanding on many aspects related to science and NOS, especially those pertaining to the 'Social-Institutional', 'Scientific Practices' and 'Educational Applications' categories. However, varied perceptions were found on some key concepts such as the role of bias and prejudices on scientific facts, the employment of same scientific practices across different branches of science, and the influence of politics in science. Misconceptions on particular aspects of NOS were also recognised (e.g. the distinction between laws and theories and the fixed nature of procedures followed in experiments). The findings suggest practical and pedagogical implications for teaching and outline an agenda for further research.

The study aimed to compare the physicochemical composition, fatty acid profile, phenolic content and volatile organic compounds (VOCs) of feta cheese produced in two regions in Greece (mountainous grasslands and plains). The VOC profiles of forage in the mountainous grasslands were also investigated in order to detect any relationship between the two profiles. Forbs were found to be the major functional group in the mountainous area and the most abundant VOCs were aldehydes, alcohols, and terpenes. Significant variations were observed between the main compositional features of the two types of cheeses, with the cheese produced from the milk of ewes and goats grazing in the mountainous region having a higher moisture content, lower fat content, and higher protein content. A total of 34 VOCs were identified and the most abundant groups in the cheese samples were esters, hydrocarbons, and alcohols. The fatty acid profile, phenolic content, and terpene profile of the cheese were also affected by the type of pasture. The cheese produced from the milk of ewes and goats grazing in the mountainous region also had a higher content of conjugated linoleic acid (CLA) and a lower content of saturated fatty acids (SFAs). These findings suggest that the grasslands grazed by ewes and goats in the mountainous region have a positive impact on the nutritional quality of feta cheese.

The comment disputes some of the inferences in the paper “Helmert Transformation Problem. From Euler Angles Method to Quaternion Algebra”, published in this journal. The key points in the dissent are the following: (1) The number of unknown parameters in the reverse transformation problem using dual quaternions. (2) The reliability of both data and the results. (3) There should be no differences between Euler angles and quaternion methods. Our response is summarized as follows: (1) The problem can be solved using either eight or nine unknown parameters. (2) All the data and results are real. (3) There should be differences between methods because of different calculations.