Apollo 7 retrofire and reentry of service propulsion module. Further study of Intelsat 2 F-2 apogee burn

Photography of Apollo 7 retrofire and service propulsion module reentry and apogee burn of Intelsat 2 F-2 satellit

Evaluating Reasonableness Tests for Longitudinal Measurement Invariance in Structural Equation Modeling using Confirmatory Factor Analysis

Researchers are typically interested in comparing groups of people and/or comparing people across time. If researchers are to conclude differences are due to group dynamics or time, we must establish that the measure(s) we are using are actually invariant across groups or time. Some statistical methods (ANOVA and regression) make this assumption without direct evaluation. Conducting analyses in the Structural Equation Modeling (SEM) framework using Confirmatory Factor Analysis (CFA) is one way the assumption of measurement invariance can be evaluated directly. Many researchers have studied multiple group invariance and current invariance testing recommendations are based on multiple group studies and simulations. There is a lack of literature on testing invariance in longitudinal designs. Current guidelines recommend researchers apply the same guidelines from multiple group to longitudinal designs. Longitudinal designs are more complicated and may need different recommendations. The current study evaluates measurement invariance in longitudinal CFA in order to ascertain if the current guidelines based off the multiple group case are acceptable when applied to the longitudinal framework

A Novel Item-Allocation Procedure for the Three-Form Planned Missing Data Design

We propose a new method of constructing questionnaire forms in the three-form planned missing data design (PMDD). The random item allocation (RIA) procedure that we propose promises to dramatically simplify the process of implementing three-form PMDDs without compromising statistical performance. Our method is a stochastic approximation to the currently recommended approach of deterministically spreading a scale\u27s items across the X-, A-, B-, and C-blocks when allocating the items in a three-form design. Direct empirical support for the performance of our method is only available for scales containing at least 12 items, so we also propose a modified approach for use with scales containing fewer than 12 items. We also discuss the limitations of our procedure and several nuances for researchers to consider when implementing three-form PMDDs using our method. The RIA procedure allows researchers to implement statistically sound three-form planned missing data designs without the need for expert knowledge or results from prior statistical modeling. The RIA procedure can be used to construct both “paper-and-pencil” questionnaires and questionnaires administered through online survey software. The RIA procedure is a simple framework to aid in designing three-form PMDDs; implementing the RIA method does not require any specialized software or technical expertise

Osseointegration of a 3D Printed Stemmed Titanium Dental Implant: A Pilot Study

In this pilot study, a 3D printed Grade V titanium dental implant with a novel dual-stemmed design was investigated for its biocompatibility in vivo. Both dual-stemmed (n = 12) and conventional stainless steel conical (n = 4) implants were inserted into the tibial metaphysis of New Zealand white rabbits for 3 and 12 weeks and then retrieved with the surrounding bone, fixed, dehydrated, and embedded into epoxy resin. The implants were analyzed using correlative histology, microcomputed tomography, scanning electron microscopy (SEM), and transmission electron microscopy (TEM). The histological presence of multinucleated osteoclasts and cuboidal osteoblasts revealed active bone remodeling in the stemmed implant starting at 3 weeks and by 12 weeks in the conventional implant. Bone-implant contact values indicated that the stemmed implants supported bone growth along the implant from the coronal crest at both 3- and 12-week time periods and showed bone growth into microporosities of the 3D printed surface after 12 weeks. In some cases, new bone formation was noted in between the stems of the device. Conventional implants showed mechanical interlocking but did have indications of stress cracking and bone debris. This study demonstrates the comparable biocompatibility of these 3D printed stemmed implants in rabbits up to 12 weeks

Fabrication of high quality plan-view TEM specimens using the focused ion beam

We describe a technique using a focused ion beam instrument to fabricate high quality plan-view specimens for transmission electron microscopy studies. The technique is simple, site-specific and is capable of fabricating multiple large, >100 μm2 electron transparent windows within epitaxially-grown thin films. A film of La0.67Sr0.33MnO3 is used to demonstrate the technique and its structural and functional properties are surveyed by high resolution imaging, electron spectroscopy, atomic force microscopy and Lorentz electron microscopy. The window is demonstrated to have good thickness uniformity and a low defect density that does not impair the film’s Curie temperature. The technique will enable the study of in–plane structural and functional properties of a variety of epitaxial thin film systems

Evaluations of People Depicted With Facial Disfigurement Compared to Those With Mobility Impairment

There are few extant studies of stereotyping of people with facial disfigurement. In the present study, two experiments (both within-participants) showed positive evaluations of people depicted as wheelchair users and, from the same participants, negative evaluations of people with facial disfigurements, compared to controls. The results of Experiment 2 suggested that implicit affective attitudes were more negative toward people with facial disfigurement than wheelchair users and were correlated with evaluation negativity. Social norms were perceived to permit more discrimination against people with facial disfigurement than against wheelchair users. These factors could help to explain the evaluative differences between the two disadvantaged groups

2020 Proceedings of the 3rd International Conference on Trauma Surgery Technology in Giessen

The 3 rd event of the Giessen International Conference on Trauma Surgery Technology on October, the 17th 2020 was hosted on Zoom in accordance with the worldwide corona situation. Dr Mieczakowski, Dr Yu, and Wolfram drafted in 2018 from Jan’s apartment in Bremen the manuscript which was submitted to and approved for funding by the Deutsche Forschungsgemeinschaft (DFG). At that time, we had no idea what substantial changes the conferencing concept would require. This is why we would like to thank again Michele. She first planned this year’s event after the 2019 date and then in the spring of 2020 had to replan for the new situation

The effect of trace levels of Ni and V on the microstructure and properties of four common aluminum alloys

The effect of nickel and vanadium with concentrations from <100ppm to ~550ppm on microstructure, mechanical properties and corrosion behavior has been investigated for aluminium alloys 356, 6060/6063, 3004 and 5182. While the Ni and V additions appeared to have no adverse effect on strength, ductility was reduced by the presence of Ni but it was improved by the presence of V for all alloys. Low Ni combined with high V levels gave the best corrosion performance in all four alloy systems. However, there was no difference in corrosion between alloys with low (50ppm) Ni and low (150ppm) V and other combinations. It appears that Ni and V levels may be allowed to increase together within current alloy specifications without detrimental effects on properties. However, high Ni and low V concentrations may reduce ductility and corrosion performance. Some caution should be exercised in allowing Ni to increase alone