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Friction Control via Tunable Interpenetration of Spherical Polyelectrolyte Brushes
No full textPolyelectrolyte brushes are promising materials for achieving superlubricity, but conventional approaches requiring chemical surface grafting limit their broad applicability. Here, we demonstrate a simple, yet effective and readily scalable friction-control strategy using spherical polyelectrolyte brushes as lubricant additives. By tuning particle concentration, we precisely control the degree of polymer chain interpenetration, a key factor determining lubrication performance. Combining scattering, viscosity, and friction measurements, we identify three distinct lubrication regimes defined by brush interpenetration. Enhanced lubrication occurs at the concentration threshold separating the semidilute partly interpenetrated regime from the semidilute fully interpenetrated regime, which aligns closely with the transition between mixed and hydrodynamic lubrication. Our results point to a direct correlation between nanoscale structural transitions and macroscale friction behavior, offering a predictive framework for enhanced lubrication in diverse industrial applications
The Concentration Grid Exercise: Effects of Silent Practice and Music Distraction on Performance, Attention, Affect, and Brain Activity
No full textWe conducted two studies using the concentration grid exercise to assess the effects of practice in silence (Study 1) and practice with loud music on the background (Study 2) on performance, attention, core affective states (arousal and pleasantness), and alpha, beta, and theta brain waves. In Study 1, we recruited 12 participants, 6 males and 6 females ( M = 27.50, SD = 8.27). In Study 2, we recruited 12 participants, 6 males and 6 females ( M = 26.36, SD = 6.67). For both Study 1 and Study 2, no significant effects were observed for performance, attention, and core affect. Marginal significant effects were observed for attention and arousal, suggesting loud music was a distraction to at least some participants. Across both studies, the electroencephalogram data revealed significant differences in alpha, beta, and theta power across pre-test and post-test trials. Collectively, these findings support the neural efficiency hypothesis; in that practice leads to a more quiescent brain state in both silent-practice and music distraction conditions. These findings also suggest that the concentration grid exercise can be an appropriate tool for research and practice
Editorial: Advances in understanding and managing dentine hypersensitivity and tooth wear
No full textTeachers' Personal and Teaching Epistemic Practices: A Four-Country Survey and Interview Exploration of Argumentation Implementation
No full textThree hundred and eighteen in-service teachers from Greece, Cyprus, Romania and Hungary participated in a professional training program aimed at promoting their metacognitive and epistemic thinking and practices, with argumentation as a prominent teaching practice. Pre-program survey results revealed that teachers' personal and teaching epistemic practices were underdeveloped, with particularly low engagement in the latter. Personal epistemic practices predicted teaching ones. Cultural differences emerged, with Greek and Cypriot teachers reporting higher engagement in both epistemic practices than Romanian and Hungarian teachers. In-depth interviews with six Greek and Cypriot teachers who implemented argumentation post-program indicated that argument-based practices improved students' epistemic understanding, particularly in appreciating multiple perspectives, evaluating sources and using evidence. Teachers acknowledged receiving limited preparation for promoting students' epistemic understanding and argumentation skills. These findings highlight the need for higher education programs to develop pre- and in-service teachers' epistemic practices. Implications for higher education and policymakers are discussed
Plant-Based-Medicinal Micronutrients Can be Used Beneficially and Cost-Effectively to Treat Metabolic and Other Diseases
No full textMicronutrients are mainly vitamins, minerals and other related phytochemical molecules which are needed by the body in very small quantities. They are found in a variety of plant and animal foods and supplements which are consumed daily to maintain a healthy body. However, a deficiency in any of them can cause severe and even life-threatening health conditions. Micronutrients perform several physiological and biochemical functions enabling the body to produce enzymes, hormones and other regulatory substances needed for normal growth, development and good health. Deficiencies in some micronutrients, including iron, magnesium, several essential vitamins (A, C, D, E and B1), iodine and others, are the most common in low- and middle-income countries (LMIC) globally, especially among children and pregnant women. In addition to abnormal health conditions and diseases, micronutrient deficiency results in reduced energy level in the body, severe mental health conditions and inability to think leading to reduced education outcomes and to perform efficiently resulting in reduced work productivity. The economic cost globally for deficiency in micronutrients is enormous. This study investigated the beneficial effects of the plant Momordica charantia or bitter melon (BM), both as food and plant-based phytomedicines in health and diseases. The results reveal that BM is rich in several essential micronutrients and phytochemical compounds which exert numerous cellular regulation processes in the body and maintaining normal growth, development and good health. The micronutrients and phytochemical compounds of BM can prevent and treat diseases as diabetes, obesity, dyslipidaemia, hypertension, cancer, dementia, skin disorders and many others. It is concluded that BM should be consumed in physiological amounts daily to enjoy a better quality of healthy life
Understanding and managing harmful sexual interests through the lens of traumatic sexuality, loss of intimacy and acceptance of solitude
No full textThis chapter explores human sexuality through a biopsychosocial lens, emphasising its biological, psychological and social determinants. It argues for trauma-informed, formulation-led interventions for individuals with harmful sexual interests, particularly towards children. Drawing on research and clinical practice, the chapter distinguishes between biologically rooted sexual orientations and environmentally acquired sexual interests. It introduces a four-stage intervention framework – grief, acceptance, containment and desistance – designed to address the trauma, shame and isolation often experienced by this population. Incorporating models such as the Motivational-Facilitation Model (MFM) and the Compositional Explanatory Theory of Paedophilia (CEToP), the approach acknowledges the unchosen nature of sexual orientation while promoting responsibility for behaviour. The chapter underscores the importance of psychoeducation, compassion-focused therapy and the development of safe, meaningful lives that reduce risk. Early feedback from a specialist prison setting suggests increased self-awareness and emotional regulation, indicating the potential value of this integrated therapeutic approach
Euclid: The first statistical census of dusty and massive objects in the ERO/Perseus field
No full textOur comprehension of the history of star formation at z>3 strongly relies on rest-frame ultraviolet observations. However, this selection systematically misses the dustiest and most massive sources, resulting in an incomplete census at earlier times. Infrared facilities such as and the Space Telescope have shed light on a hidden population lying at z=3--6 characterised by extreme red colours named HIEROs (HST-to-IRAC extremely red objects), identified by the colour criterion ̋E - > 2.25. Recently, Euclid Early Release Observations (EROs) have opened the possibility to further study such objects, exploiting the comparison between Euclid and ancillary /IRAC observations. The aim of this study was to investigate the effectiveness of this synergy in characterising the population of a small test area of 232,arcmin2 u g r ̊m H ,α, i , and ) already included in the ERO catalogue. We selected 121 HIEROs by applying the ̋E - > 2.25 colour cut, cleaned this sample of globular clusters and brown dwarfs, and then inspected by eye the multi-band cutouts of each source, ending with 42 reliable HIEROs. Photometric redshifts and other physical properties of the final sample were estimated using the spectral-energy-distribution-fitting software . From the z_ z ch2 Bagpipes phot and M_* values, we computed the galaxy stellar mass function at 3.5<z<5.5. When we exclude all galaxies that could host an active galactic nucleus, or whose stellar masses might be overestimated, we still find that the high-mass end of the galaxy stellar mass function is similar to previous estimates, indicating that the true value could be even higher. This investigation highlights the importance of a deeper study of this still mysterious population, in particular to assess its contribution to the cosmic star-formation rate density and its agreement with current galaxy evolution and formation models. These early results demonstrate Euclid's capabilities to push the boundaries of our understanding of obscured star formation across a wide range of epochs
Morning endurance training induces superior performance adaptations compared to afternoon training in mice
No full textEndurance performance exhibits time-of-day variation in both humans and rodents, peaking in the late active-phase. However, whether the timing of endurance training influences performance adaptations remains unclear.
To investigate, female mice were trained 5-d/week for 6-weeks at either ZT13 or ZT22, using treadmill running at 70% of each animal's maximal capacity. Endurance performance was assessed at baseline, week-3, and week-6. Secondary outcomes included blood glucose and lactate, cage activity, body composition, liver and skeletal muscle glycogen content, mitochondrial and contractile protein expression.
At baseline, late-active phase (ZT22)-tested mice exhibited significantly higher endurance capacity than early-active phase (ZT13)-tested mice (P0.05), despite lower absolute training volumes in the ZT13 group. Both training groups reduced fat-mass (ZT13: −31%,ZT22: −32%; P0.05). In skeletal muscle, ZT13-trained mice were associated with increased (P0.05) in mitochondrial content.
ZT13-training elicited superior performance adaptations despite lower absolute workloads, indicating enhanced training efficiency. These findings identify exercise timing as a biologically relevant factor influencing endurance adaptation and variability in exercise responses
Interchangeability of external player load variables from different athlete tracking systems in English Premier League soccer players
Get PDFThis study aimed to assess the interchangeability between tracking variables derived from Global Positioning System (GPS) and those of an Optical Tracking System (OTS) in elite soccer players. Twenty-six male professional outfield soccer players (age 27±4 years, height 182±6.67 cm, mass 80.73±7.74 kg) from an English Premier League (EPL) team formed the sample. Positional information was recorded using a GPS (10 Hz Apex, STATSports, Belfast, UK) and concomitantly by an OTS using six semi-automated HD cameras sampling at a frequency of 25 Hz (Second Spectrum, Los Angeles, USA). While differences exist for both total distance and high-speed running (HSR) between the GPS and OTS, the GPS was highly correlated with the OTS (r2 > 0.99). The OTS displayed the highest values across all three examined variables. Total distance was 4% higher on average when utilising the OTS, while HSR and sprint distance were 12% and 18% higher respectively. Given its importance and the differences observed, regression equations should be utilised to align GPS and OTS data to allow practitioners to evaluate running performance and optimally prepare players for the demands of the game more effectively