We report a novel crossover behavior in the long-range-ordered phase of a prototypical spin-1/2 Heisenberg antiferromagnetic ladder compound (C_{7}H_{10}N)_{2}CuBr_{4}. The staggered order was previously evidenced from a continuous and symmetric splitting of ^{14}N NMR spectral lines on lowering the temperature below T_{c}≃330 mK, with a saturation towards ≃150 mK. Unexpectedly, the split lines begin to further separate away below T^{*}∼100 mK, while the linewidth and the line shape remain completely invariable. This crossover behavior is further corroborated by the NMR relaxation rate T_{1}^{-1} measurements. A very strong suppression reflecting the ordering, T_{1}^{-1}∼T^{5.5}, observed above T^{*}, is replaced by T_{1}^{-1}∼T below T^{*}. These original NMR features are indicative of the unconventional nature of the crossover, which may arise from a unique arrangement of the ladders into a spatially anisotropic and frustrated coupling network.
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Nutrients
December 2024
Charles Perkins Centre, University of Sydney, Sydney, NSW 2006, Australia.
Importance: Although prolonged fasting has become increasingly popular, the favourable biological adaptations and possible adverse effects in humans have yet to be fully elucidated.
Objective: To investigate the effects of a three-day water-only fasting, with or without exercise-induced glycogen depletion, on autophagy activation and the molecular pathways involved in cellular damage accumulation and repair in healthy humans.
Design: A randomised, single-centre, two-period, two-sequence crossover trial.
Children (Basel)
December 2024
Postgraduate Specialization Program in Paediatric Dentistry, Faculty of Dentistry, Complutense University of Madrid, 28040 Madrid, Spain.
Aim: The aim of this study was to evaluate the relationship between oral hygiene (OH) efficiency and manual dexterity skills in Spanish five-year-old children using two fine motor tests.
Methods: A cross-sectional study with a pre-post evaluation was designed. The children's OH was measured according to the Silness and Löe plaque index (PI) before toothbrushing upon arrival at school (pre) and after supervised toothbrushing (post).
Behav Sci (Basel)
December 2024
Department of Early Childhood Education, College of Social Science, Gachon University, Seongnam-si 13120, Republic of Korea.
Based on emotional security, stress, and spillover and crossover theories, this study aimed to examine the indirect pathways between destructive and constructive interparental conflict, parenting stress, unsupportive parenting, and child insecurity six months later. Using data from two time points beginning when Korean children ( = 159) were approximately 3-5 years old, two dual-mediation models of the relevant variables were constructed. The results indicate that destructive conflict is associated with higher levels of parenting stress, whereas constructive conflict is associated with lower levels of stress.
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January 2025
Proof of Concept Center, Eastern Hepatobiliary Surgery Hospital, Third Affiliated Hospital, Second Military Medical University, Naval Medical University, No. 255, Yangpu District, Shanghai, 200433, China.
Objectives: The objective was to investigate the role of double extraction in reducing data errors in evidence synthesis for pharmaceutical and non-pharmaceutical interventions.
Design: Crossover randomized controlled trial (RCT).
Setting: University and hospital with teaching programs in evidence-based medicine.
The centromere effect (CE) is a meiotic phenomenon that ensures meiotic crossover suppression in pericentromeric regions. Despite being a critical safeguard against nondisjunction, the mechanisms behind the CE remain unknown. Previous studies have shown that various regions of the pericentromere, encompassing proximal euchromatin, beta and alpha heterochromatin, undergo varying levels of crossover suppression, raising the question of whether distinct mechanisms establish the CE in these different regions.
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