Latent Profiles of Students at Social-Emotional Risk: Heterogeneity Among Peer-Rejected Students in Early Elementary School

A latent profile analysis was applied to explore heterogeneity in the social and classroom behaviors of 224 peer-rejected elementary school students (56% White, 68% male, Grades 1–4, Mage = 8.1 years). Profile indicators included teacher ratings of social skills and problem behaviors on the Social Skills Improvement System (SSIS) and peer nominations of prosocial, aggressive, and withdrawn behavior. Four profiles emerged. Two profiles where characterized by elevated externalizing problems by peer and teacher report, one with multiple co-occurring difficulties (multiproblem, 21% of the sample) and one characterized primarily by aggression (domineering, 32% of the sample). Another profile was characterized by deficits in social skills and viewed by teachers as internalizing and disruptive (internalizing-dysregulated, 26% of the sample.) The final profile was nondistinct on teacher ratings but defined by low rates of prosocial behavior by peers (teacher preferred, 21% of the sample.) Group comparisons revealed that students in the multiproblem and internalizing-dysregulated profile classes had lower-quality relationships with teachers and more academic difficulties than students in the other two profile classes. The findings are discussed in terms of implications for identifying peer-rejected students for Tier 2 interventions and tailoring those interventions to enhance impact.

Precision Rock Excavation: Beyond Controlled Blasting and Line Drilling

The strictness of the result of an excavation, whether mechanical or by means of explosives, is naturally conditioned by its objective and, therefore, by the type of technique applied to achieve it. To attain the best results in terms of rock breakage, and with respect to the final profile, it is important to evaluate the specific excavation energy and its optimization. This study, being a revision of different techniques to achieve good quality of the final walls, focuses on evaluating the effects of those techniques on the quality of the result, in both open-pit and underground operations. Different geometries and configurations can be applied to both quarrying and tunneling blasts. This study aims to push contour blasts to their limits, and the main aspects are discussed in order to improve the blast parameters in daily practice.

Precision Rock Excavation: Beyond Controlled Blasting and Line Drilling

The strictness of the result of an excavation, whether mechanical or by means of explosives, is naturally conditioned by the objective, and therefore by the type of technique applied to achieve it. To attain the best results in terms of rock breakage and respect of the final profile, it’s important to evaluate the excavation specific energy and its optimization. This research focuses on evaluating the effects of different techniques on the quality of final walls in open-pit and underground operations. Different geometries and configurations can be applied to both quarrying and tunnelling blasts. The research is aimed to push contour blasts to their limits, and the main aspects are discussed in order to improve the blast parameters in the daily practice.

A Simulation Method for Free-form Milling Cylindrical Gears With Disc Cutters

Free-form milling is a flexible gear machining method that allows using general disc cutters to machine various gear types on a 5-axis machine tool. This paper proposes a two-dimensional simulation method for free-form milling of cylindrical gears with disc cutters. A mathematical model for free-form milling of cylindrical gears with disc cutters is constructed. By analyzing the spatial positional relationships between the cutter and the workpiece, the instantaneous contact line is derived and projected onto the gear end face, and then the projected curves are intersected to obtain the final profile. This calculation method realizes the rapid simulation of the actual cutting condition on the gear end face, which is beneficial to the judgment of machining interference and the analysis of the tooth profile accuracy during the gear machining process.

Are S-PRG Based Composites Able to Resist and Protect the Adjacent Enamel Against Erosive Wear?

This in-vitro study evaluated the resistance of S-PRG-based-composites against erosive wear and their protective effect on enamel adjacent to restoration. Bovine-enamel-blocks were randomized into 12 groups (n=10/group), according to the factors material and type of wear (erosion-e or erosion+abrasion-a): S-PRG-based-composite-Beautifil II®(SPRGe/SPRGa); S-PRG-based bulk-fill-Beautifil Bulk Restorative®(SPRGBFe/SPRGBFa); composite-Filtek Z350 XT®(RCe/RCa); bulk-fill-composite-Filtek Bulk Fill®(BFe and BFa); glass-ionomer cement-EQUIA Forte®(GICe/GICa); resin-modified glass-ionomer cement-Riva®(RMGICe/RMGICa). Standardized cavities were prepared in specimens and restored. Initial profile was performed on the material and on the adjacent enamel at distances of 100/200/300/600 and 700μm. Specimens were immersed in 0.5%citric-acid (2min-6x/day-during 5days), and abrasive challenge was performed using a toothbrushing-machine (1min-after erosive challenge). Final profile was obtained following initial. Data were analyzed by two-way ANOVA and Tukey-test (α<0.05). On erosion, the GICe and RMGICe groups presented greater loss of material compared to other groups; up to 300μm away from the restoration, GICe and SPRGBFe were able to promote less enamel loss than composite groups. For erosion+abrasion S-PRG-based groups showed intermediate material wear compared to GICs (higher wear) and composites (less wear); there was no difference of enamel wear adjacent to restorations among groups. It is concluded that S-PRG-based-composites are a good alternative for restorative treatment of erosive tooth wear.Clinical Significance: S-PRG-based composite restorations are able to diminish surrounding enamel erosive wear, similarly to glass ionomer cement, with the advantage of being more resistant to erosive challenge. Therefore, this material is a potential option to restore advanced erosion lesions in patients with etiological factors still present.

Statistical Analysis and Trend Detection of the Hydrological Extremes in the Váh River at Liptovský Mikuláš

Natural climate fluctuation, as well as expected climate change, brings additional water regimes in the flow of a number of serious issues and uncertainties. The upper parts of the river basins are suitable for studying the effect of potential climate change or increased air temperature on drainage conditions in the basin. The Váh River is the biggest left-side Danube River tributary and the second biggest river in Slovakia. Gauging station Váh – Liptovský Mikuláš is the final profile above the water reservoir Liptovská Mara, one of the largest reservoirs in Slovakia. The contribution deals with the trend analysis of the extreme flows regime and the waves volume belongs to the annual maximum flow at gauging station Váh – Liptovský Mikuláš in a selected time period (1931–2015). Consequently, the trend analyses of precipitation depth and air temperature have been made at three selected meteorological stations located in the upper part of the Váh River basin. We have used the Mann-Kendall nonparametric test, which is one of the most widely used nonparametric tests to detect significant trends in a time series.

Design of a Variable-Stiffness Compliant Skin for a Morphing Leading Edge

A seamless and smooth morphing leading edge has remarkable potential for noise abatement and drag reduction of civil aircraft. Variable-stiffness compliant skin based on tailored composite laminate is a concept with great potential for morphing leading edge, but the currently proposed methods have difficulty in taking the manufacturing constraints or layup sequence into account during the optimization process. This paper proposes an innovative two-step design method for a variable-stiffness compliant skin of a morphing leading edge, which includes layup optimization and layup adjustment. The combination of these two steps can not only improve the deformation accuracy of the final profile of the compliant skin but also easily and effectively determine the layup sequence of the composite layup. With the design framework, an optimization model is created for a variable-stiffness compliant skin, and an adjustment method for its layups is presented. Finally, the deformed profiles between the directly optimized layups and the adjusted ones are compared to verify its morphing ability and accuracy. The final results demonstrate that the obtained deforming ability and accuracy are suitable for a large-scale aircraft wing.

Nonlinear mechanical model of the shaft of a roll forming mill and parameter identification

Roll forming is a continuous process in which a moving metal sheet passes through numerous pairs of opposing forming rolls. The shafts of the roll forming mill are equipped with these rolls and must be set up and aligned to achieve the required final profile of the sheet. The practically relevant task of predicting the profile geometry of this incremental rolling process with varying characteristics of the metal sheet entering the mill requires an accurate description of the stiffness behavior of the shaft with rolls, which is the most compliant part of the roll forming mill. In this paper, the measured force-deflection characteristic of the shaft without rolls is compared with predictions of various theoretical models, followed by the adoption of the shear deformable beam model of the shaft with nonlinear elastic supports in the bearings. The coefficients of the cubic stiffness characteristics of the rotational springs as well as the effective length between the supports are identified based on the experimental data for the deflections, measured along the shaft for various loading levels. The theoretical predictions are obtained via the nonlinear finite element model of the shaft. The model thus provided shows high accuracy compared with the measurements. The paper’s results serve as a foundation for models to predict the stiffness of shafts with rolls.

THE TREATMENT EFFECTS OF THE COMBINED APPROACH: BRACESWITH PREFABRICATED MYOFUNCTIONALAPPLIANCE FOR GROWING CLASS II PATIENT

Objective:To evaluate the effect of combined treatment approach: braces with myofunctional appliance (trainer-T4B) on dentoalveolar, sagittal and vertical skeletal level in growing individuals with Skeletal and Dental Class II. Methods:Twenty teenagers with permanent dentition were treated with fixed appliance-braces in combination with myofunctional appliance (trainer-T4B). All patient completed thetreatment with occlusal Class I molar relationship. The patients made initial and final profile X-rays with cephalometric analysis. The evaluation of the treatment effects was made by comparing the initial and the final cephalometric analysis. Results:Significant sagittal skeletal changes were observed on all sagittal skeletal parameters, except for SNA°. A high positive association was found between the ANB angle change and Wits change. The changes in the rest of the vertical skeletal measurements were significant for two, including SN-M° and Go°. The dentoalveolar measurements showedsignificant changes in all parameters, except for i/M° where the change was marginally significant. Conclusion:The chosen treatment approachwaseffective for growing skeletal and dental Class II patients with permanent dentition.