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One challenge for 3D printing is that the mortar must flow easily through the printer nozzle, and after printing, it must develop compressive strength fast and high enough to support the layers on it. This requires an exact and difficult control of the superplasticizer (SP) dosing. Nanocrystalline cellulose (CNC) has gained significant interest as a rheological modifier of mortar by interacting with the various cement components. This research studied the potential of nanocrystalline cellulose (CNC) as a mortar aid for 3D printing and its interactions with SPs. Interactions of a CNC and SP with cement suspensions were investigated by means of monitoring the effect on cement dispersion (by monitoring the particle chord length distributions in real time) and their impact on mortar mechanical properties. Although cement dispersion was increased by both CNC and SP, only CNC prevented cement agglomeration when shearing was reduced. Furthermore, combining SP and CNC led to faster development of compressive strength and increased compressive strength up to 30% compared to mortar that had undergone a one-day curing process.

Background: The purpose of this study was to do a systematic review and meta-analysis about the anthropometric, physiological, and physical performance that discriminate the physical talent in basketball., Methods: The search was conducted using the most relevant databases as Web of Science, PubMed, SPORTDiscus and Scopus, according to the PRISMA (2020) guideline. Keywords such as "basketball", "talented identification", "anthropometric", "physiology" and "physical performance" were used for the search, in English and following the "PICOS" question model. Eighteen articles' overall methodological quality was assessed using the Critical Review Forms., Results: The study found in basketball, height, body mass, Yo-Yo test, T -test, 20 m sprint, and jump performance had statistical significance between elite and non-elite groups, including different positions and levels., Conclusions: The reviewed literature highlighted a complicated relationship between anthropometric, physiological, and physical performance. Based on the results of the study, it's possible that height, body mass, agility, speed, endurance capacity, and lower lamb power could affect the early development of basketball., 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. The author(s) declared that they were an editorial board member of Frontiers, at the time of submission. This had no impact on the peer review process and the final decision., (© 2023 Han, Gómez-Ruano, Calvo and Calvo.)

In this study, different lightweight expanded glass aggregates (LEGAs) were produced from glass cullet and various carbonated wastes, through a thermal impact process. The effects of LEGA microstructure and morphology on both the adherence to the cement paste and the mechanical properties of mortars after 28 days of curing were studied. The properties of lightweight mortars made of either LEGAs or expanded clay aggregates were compared. The results demonstrated the feasibility of using LEGAs to produce glass lightweight aggregate mortar, with flexural and compressive strength values ranging from 5.5 to 8.2 MPa and from 28.1 to 47.6 MPa, respectively. The differences in mechanical properties were explained according to the microstructures of the fracture surfaces. Thus, arlite-type ceramic aggregates presented surface porosities that allowed mortar intrusion and the formation of an interconnected interface; although the surfaces of the vitreous aggregates were free from porosity due to their vitreous nature, the mortars obtained from different wastes presented compressive and flexural strengths in the range of lightweight mortars.

Presence of microcracks in concrete can diminish the service life of a structure. The injection of materials for filling the crack is proposed for facing this problem. The traditional materials used for sealing cracks present some drawbacks, such as the difficulties of inorganic materials for flowing to all the depth of the crack and the lack of compatibility with the cementitious matrix in the case of organic materials. In this work, the injection of colloidal nanosilica dispersed in water is proposed for filling microcracks in mortars. The effect of the injection procedure on the sealing performance of the colloidal nanosilica has been assessed. The ability of colloidal nanosilica for penetrating through the crack and its posterior gelification-solidification inside the crack after a curing period have been confirmed. The microscopic analysis of a cross-section of the crack indicates that the sealing ability of the nanosilica seems to be not only due to the filling of the crack but also to chemical interactions with the cementitious phases of the surrounding crack sides.

Background: The aims of the study were (1) to identify the physical fitness and basic anthropometric characteristics of Polish female basketball players aged 13-15 years, (2) to show the effect of maturity timing on the performance in motor tests and basic body composition parameters, (3) to identify the index that contributes most to the prediction of performance in the tests of speed, jumping ability, agility, and endurance., Methods: The sample included 904 female Polish players (U13-15). In part 1, maturity timing category distribution were examined within across age-groups. Maturity timing was followed by grouping with respect to years before or after the observed peak high velocity (PHV): PHV0 (- 0.50 to 0.49), PHV1 (0.50 to 1.49), PHV2 (1.50 to 2.49) and PHV3 (2.50 to 3.49). In part 2, the relationship between the anthropometric variables, physical fitness performance was assessed based on maturity timing categories (ANCOVA analysis). In part 3, backward stepwise multiple regression analyse quantified the relationship between maturity timing (group of PHV) and physical performance., Results: ANCOVA results (age, body height, and body mass as covariates) showed in the U13 female basketball players significantly higher sprinting (20 m), jumping ability and endurance tests results of the PHV1 group. Better results was observed in U14 female players in PHV1 compared to PHV2 and PHV3 in 20 m and jumping tests but opposite trend was observed for 5 m sprint and endurance test (distance covered and VO2 max ). U15 basketball players from the PHV3 group were characterized by better results of jumping abilities, endurance, 10 m and 20 m sprint and agility (total, S 4 ) tests. Maturity timing (10 m), chronological age (5 m, 20 m, agility, SVJ, VJ, and VO 2max tests), body height (10 m), body mass (10 m, 20 m, VJ, VO 2max ), and the interaction between body mass and height (SVJ) were significant (adjusted R 2  = 0.02-0.10; p < 0.001) predictors of motor skills., Conclusion: Trainng content of female basketball players aged 13-15 years old should be adjusted to biological requirements especially in jumping, endurance and 20 m sprint test. The time from peak height velocity (PHV) was a significant predictor only in the 10 m sprint test., (© 2022. The Author(s).)

This study looks at the effects of exercise programs on physical factors and safety in adult patients with cancer and hematopoietic stem cell transplantation (HSCT) or bone marrow transplantation (BMT). A systematic search was performed in the PubMed and Web of Science databases (from inception to 26 August 2021). A review was carried out following the Preferred Reporting Items for Systematic review and Meta-Analyses (PRISMA) checklist. The methodological quality of the included studies was assessed with the Physiotherapy Evidence Database (PEDro) scale, based, in turn, on the Delphi list. A total of 25 randomized controlled trials studies were included, comprising 1434 patients. The most significant result of this systematic review is that exercise program interventions are safe and produce positive changes in cardiorespiratory fitness, muscle strength, and the functional mobility-state in adult patients with cancer and HSCT or BMT. Only 3 patients from the 711 participants in the exercise interventions (i.e., 0.42%) reported adverse events related to exercise interventions. Moreover, exercise training programs may have a cardiological and muscular protective effect, as well as a healthy effect on the prevention and control of transplant complications, improving health outcomes.

Fiber reinforcement of concrete is an effective technique of providing ductility to concrete, increasing its flexural residual strength while reducing its potential for cracking due to drying shrinkage. There are currently a wide variety of industrial fibers on the market. Recycled steel fibers (RSF) from tires could offer a viable substitute of industrialized fibers in a more sustainable and eco-friendly way. However, mistrust exists among users, based on fear that the recycling process will reduce the performance, coupled with the difficulty of characterization of the geometry of the RSF, as a consequence of the size variability introduced by the recycling process. This work compares the behavior of RSF from tires compared with industrialized steel or polypropylene fibers, evaluating the fresh state, compressive strength, flexural residual strength, and drying behavior. The concept of Equivalent Fiber Length (EFL) is also defined to help the statistical geometrical characterization of the RSF. A microstructural analysis was carried out to evaluate the integration of the fiber in the matrix, as well as the possible presence of contaminants. The conclusion is reached that the addition of RSF has a similar effect to that of industrialized fibers on concrete's properties when added at the same percentage.