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Objective: This study aimed to see if increasing the concentration of nutmeg flesh extract in vitro could increase the growth of Lactobacillus plantarum bacteria and if it had any effect on broiler chicken performance. Materials and Methods: Different concentrations of nutmeg flesh extract (5, 10, 15, and 20/100 ml distilled water) were combined with 10 ml L. plantarum (bacterial concentration 1 × 109 cfu/ml) to produce synbiotics. A total of 250 unsexed Lohmann broiler chickens were reared together from 0 to 7 days of age in the in vivo study. Beginning on day 8, synbiotics nutmeg flesh extract and L. plantarum were added to the ration in amounts of 0.5, 1, 1.5, and 2 ml/kg for T1, T2, T3, and T4, respectively, while no synbiotics were added to the control diet (T0). Results: The levels of nutmeg flesh extract had a significant (p < 0.05) effect on L. plantarum growth. In the survival test against gastric acid, bile salts, and temperature, the addition of nutmeg flesh extract (20/100 ml distilled water) significantly (p < 0.05) maintained the population of L. plantarum. In vivo studies showed that the T1,T2,T3, and T4 groups gained more body weight (p < 0.05) than the T0 group during the rearing period but had no effect (p > 0.05) on the internal organ weight and carcass of broiler chickens. Conclusions: Nutmeg flesh extract could stimulate the growth of L. plantarum bacteria, and using it as a synbiotic could improve broiler chicken performance.
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Rapid changes in the 21st century demand the use of technology in learning geometry in elementary schools. One such technology is augmented reality (AR). 3Dmetric (3D and Geometric) is a geometry learning medium on AR-based 3D space material. Students' perceptions, which refer to their interpretation, are a key factor in studying the changes in their interpretations of a particular phenomenon. The purpose of the current study was to investigate the perceptions of elementary school students after using 3Dmetric to learn geometric shapes. The differences and the relationship between the students' level of perception and level of spatial ability were also investigated. This study applied a cross-sectional approach with quantitative and qualitative designs. A total of 36 students in one elementary school in Indonesia participated in this study. The instruments used were the Perception Scale for Using 3Dmetric in Geometry Teaching, Spatial Ability Scale, and In-Depth Interview Form. Results showed that the positive perception of elementary school students regarding the use of 3Dmetric does not depend on the level of their spatial ability. Moreover, the difference in their perceptions is not caused by the level of their spatial ability. The positive findings in this cross-sectional study can contribute to the success of AR-based learning and teaching in the 21st century, especially with regard to learning materials for 3D geometry. They can also lead to the formation of the spatial abilities and improvement in the academic performance of elementary school students.
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Beam deflection due to axial channeling in a silicon crystal bent along the 111 axis was observed with 400 GeV/c protons at the CERN Super Proton Synchrotron. The condition for doughnut scattering of protons by the atomic strings of the crystal was attained. Such a condition allowed one to observe a beam deflection of 50 murad with about 30% efficiency. The contribution of hyperchanneled states of protons to the observed beam deflection was less than 2% according to simulation results.
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The volume reflection phenomenon was detected while investigating 400 GeV proton interactions with bent silicon crystals in the external beam H8 of the CERN Super Proton Synchrotron. Such a process was observed for a wide interval of crystal orientations relative to the beam axis, and its efficiency exceeds 95%, thereby surpassing any previously observed value. These observations suggest new perspectives for the manipulation of high-energy beams, e.g., for collimation and extraction in new-generation hadron colliders, such as the CERN Large Hadron Collider.