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This study investigates the effect of the amount (from 0.6 % to 1.4 %) of crystallizing admixture (CA) on the shrinkage, density, porosity and mechanical properties of concrete specimens. A higher content of CA increased the total porosity of concrete from 10.6 % to 11.15 %. In contrast to the specimens containing 0.8- 1.0% of CA, the lowest amount of closed pores and highest total porosity was observed in the specimens containing 1.2 %-1.4 % of the CA. Compared to the control specimen, concrete specimens containing 1.4 % of CA showed a 5.4 % decrease in flexural strength and a 13.6 % decrease in compressive strength after 28 days of curing. The specimens containing 0.9 %-1.0 % of CA demonstrated the lowest shrinkage in the period of 190 days. The shrinkage of these specimens reduced 4.8 %-4.9 % compared to the control specimen. Higher content of CA had an opposite effect on the shrinkage, a short-term expansion of specimens was observed after 28-56 days. Taking into account all the properties of the concrete specimen, the optimum amount of CA, which could prevent cracks in the structures is 1.0% of the cement mass.

The development of mental toughness in student athletes within sports schools is crucial for identifying strengths and improving weaknesses to optimize performance. This study aimed to assess the effectiveness of a mental toughness development program for basketball sports school students. Sixty-two male student athletes, aged 15.83 ± 0.37 years, participated, with 30 in the experimental group and 32 in the control group. They completed the Mental Toughness Questionnaire 48 (MTQ48) before and after the 6-week intervention program. Pearson's correlations were calculated for study variables. A repeated measures MANOVA followed by one-way ANOVA analyzed differences in mental toughness skills between groups and over time. Results showed a significant effect of the intervention program on mental toughness skills, with small and medium effect sizes. Post-program, the experimental group exhibited higher levels of various skills compared to controls, including skills related to challenge, commitment, emotional control, life control, overall control, self-confidence in interpersonal interactions, self-confidence in one's abilities, overall self-confidence, and total MTQ48. These findings underscore the utility of interventions for enhancing mental toughness among basketball sports school students, emphasizing the importance of tailored approaches in such intervention programs., Competing Interests: The authors declare no conflicts of interest.

Assessing psychological indicators such as positive behavioral skills in the context of adolescent personality development during the pandemic era is highly relevant: the growing problem of peer disrespect among adolescents who participate in sports has recently become an undeniable scientific issue. This study aimed to analyze positive behavioral skills in the cadet (U16) and junior (U18) age groups of young basketball players during the COVID-19 pandemic. The participants were 378 male athletes (age 16.36 ± 1.15 years). Results revealed that U18 athletes are more capable of taking responsibility, positively evaluating themselves, behaving pro-socially with teammates, cooperating, demonstrating assertiveness, demonstrating self-control, and managing emotions than U16 adolescent athletes. When comparing the effect sizes in the current study during the pandemic with similar studies by other authors, the pandemic may have had a larger negative effect on some positive behavioral skills (ability to control emotions, social responsibility skills, cooperation skills) in U16 athletes than in U18 athletes, as the effect sizes were small before the pandemic and moderate during the pandemic in the current study. This study's results may be useful for developing and implementing a young athletes' education program based on a comprehensive model of positive behavioral skills that include the indicators analyzed.

In the concrete manufacturing industry, a large amount of waste is generated. Such waste can be utilised in the production of more sustainable products with a low carbon footprint. In this study, concrete sludge, a difficult-to-utilise waste that is obtained from residual concrete by washing a concrete truck, was investigated. During washing, aggregates from the concrete mixture are separated, and the remaining insoluble fine particles combine with water to form concrete sludge. Dried and wet concrete sludge were used in the tests. Samples with different compositions were produced with dried and wet concrete sludge, cement, superplasticiser, and tap water. Seven cement pastes with different compositions were made by partially replacing cement with dried concrete sludge (0%, 5%, 10%, 15%, 20%, 25%, and 30%). In compositions with wet concrete sludge, cement was replaced by the same amounts as in the case of dried concrete sludge. The slump, setting time, and their changes with different amounts of concrete sludge were determined for fresh cement pastes. It was found that with different forms of concrete sludge, the technological properties of the mixtures change, and the setting time decreases. The density and compressive and flexural strength results were confirmed by SEM and XRD tests. The research results show that dry concrete sludge causes the deterioration of the mechanical properties of cement stone, while wet concrete sludge improves the mechanical properties of cement stone. However, it was found that replacing 5% cement with dry concrete sludge does not significantly affect the properties of hardened cement stone. In mixes with wet concrete sludge, the recommended amount of replaced cement is 10%, because the technological properties of the mixture are strongly influenced by larger amounts.

Triggering receptor expressed on myeloid cells-2 (TREM2) is a cell surface receptor on macrophages and microglia that senses and responds to disease-associated signals to regulate the phenotype of these innate immune cells. The TREM2 signaling pathway has been implicated in a variety of diseases ranging from neurodegeneration in the central nervous system to metabolic disease in the periphery. Here, we report that TREM2 is a thyroid hormone-regulated gene and its expression in macrophages and microglia is stimulated by thyroid hormone and synthetic thyroid hormone agonists (thyromimetics). Our findings report the endocrine regulation of TREM2 by thyroid hormone, and provide a unique opportunity to drug the TREM2 signaling pathway with orally active small-molecule therapeutic agents., Competing Interests: Declaration of interests The authors declare the following competing financial interest(s): S.J.F. and T.S.S. are inventors of licensed patent applications claiming central nervous system-penetrating prodrugs of nuclear receptor modulators and their uses, including drugs acting on the thyroid hormone receptors. T.S.S., D.B., and B.E. are co-founders of Autobahn Therapeutics, and T.S.S. is a Senior Advisor to Autobahn Therapeutics., (Copyright © 2021 Elsevier Ltd. All rights reserved.)

Background: Fast, effective, and rapid processing of central nervous system (CNS) tissue with good preservation of myelin, especially in tissue from diseased mice, is important to many laboratories studying neurosciences., New Method: In this paper, we describe a new method to process and embed CNS tissue from mice. Spinal cords and optic nerves from naive C57BL/6 mice were used to standardize the microwave protocol following perfusion with fixative. The CNS tissue was processed and embedded using the microwave embedding protocol., Results: We observed that the tissue is well preserved and good quality light and electron microscope images were obtained after using the microwave embedding protocol., Comparison With Existing Methods: Traditional way of embedding CNS tissue in resin is challenging and time consuming. The microwave technology offers an efficient way to quickly embed CNS tissue while preserving morphology and retaining the integrity of the myelin., Conclusions: This new method is fast, reliable and an effective way to embed CNS tissue in resin., (© 2019 The Authors.)

The anti-oxidant lipoic acid (LA) is beneficial in murine models of multiple sclerosis (MS) and has recently been shown to slow brain atrophy in secondary progressive MS. The mechanism of these effects by LA is incompletely understood but may involve effects on microglia. The objective of this study is to understand how LA affects microglial cells. We cultured primary microglial cells from C57BL/6 adult mice brains and stimulated the cells with lipopolysaccharide (LPS) and interferon gamma (IFN-γ) in the presence or absence of LA. We demonstrate the inhibition of phagocytosis, rearrangement of actin, and formation of membrane blebs in stimulated microglia in the presence of LA. These experiments suggest that LA causes changes in microglial actin, which may lead to alterations in phagocytosis, mobility, and migration., (Copyright © 2019 Elsevier B.V. All rights reserved.)

Oligodendrocyte processes wrap axons to form neuroprotective myelin sheaths, and damage to myelin in disorders, such as multiple sclerosis (MS), leads to neurodegeneration and disability. There are currently no approved treatments for MS that stimulate myelin repair. During development, thyroid hormone (TH) promotes myelination through enhancing oligodendrocyte differentiation; however, TH itself is unsuitable as a remyelination therapy due to adverse systemic effects. This problem is overcome with selective TH agonists, sobetirome and a CNS-selective prodrug of sobetirome called Sob-AM2. We show here that TH and sobetirome stimulated remyelination in standard gliotoxin models of demyelination. We then utilized a genetic mouse model of demyelination and remyelination, in which we employed motor function tests, histology, and MRI to demonstrate that chronic treatment with sobetirome or Sob-AM2 leads to significant improvement in both clinical signs and remyelination. In contrast, chronic treatment with TH in this model inhibited the endogenous myelin repair and exacerbated disease. These results support the clinical investigation of selective CNS-penetrating TH agonists, but not TH, for myelin repair.

Cortical lesions are a crucial part of MS pathology and it is critical to determine that new MS therapies have the ability to alter cortical inflammatory lesions given the differences between white and gray matter lesions. We tested lipoic acid (LA) in a mouse focal cortical EAE model. Brain sections were stained with antibodies against CD4, CD11b and galectin-3. Compared with vehicle, treatment with LA significantly decreased CD4+ and galectin-3+ immune cells in the brain. LA treated mice had fewer galectin-3+ cells with no projections indicating decrease in the number of infiltrating monocytes. LA significantly reduces inflammation in a focal cortical model of MS., (Copyright © 2015 Elsevier B.V. All rights reserved.)

Co-administration of opioids and cannabinoids can enhance pain relief even when administered on different days. Repeated systemic administration of morphine has been shown to enhance the antinociceptive effect of tetrahydrocannabinol (THC) administered 12h later, and repeated microinjection of the cannabinoid receptor agonist HU-210 into the ventrolateral periaqueductal gray (PAG) has been shown to enhance the antinociceptive effect of morphine administered 1 day later. The primary objective of the present study was to test the hypothesis that this cannabinoid/opioid interaction is bidirectional. Experiment 1 showed that microinjection of morphine into the ventrolateral PAG of male Sprague-Dawley rats twice daily for 2 days enhanced the antinociceptive effect of HU-210 measured 1 day later. In Experiment 2, twice daily systemic injections of THC enhanced the antinociceptive effect of morphine administered 1 day later. These results complement the previously mentioned studies by showing that morphine and cannabinoid interactions are bidirectional and that the ventrolateral PAG plays an important role in this effect. In contrast to the PAG, repeated administration of HU-210 or the cannabinoid receptor agonist, WIN 55,212-2, into the RVM had a neurotoxic effect. Rats became ill following repeated cannabinoid administration whether given alone or with morphine. Presumably, this neurotoxic effect was caused by the high cannabinoid concentration following RVM microinjection because rats did not become ill following repeated systemic THC administration. These findings indicate that alternating opioid and cannabinoid treatment could produce a longer lasting and more potent analgesia than either compound given alone., (Copyright © 2012 Elsevier Inc. All rights reserved.)