Progress Towards Alignment of Multi-Order Diffractive Engineered (MODE) Lens Segments using the Kinematically-Engaged Yoke System (KEYS) for Optical Performance Testing

The continued development of multi-order diffractive engineered (MODE) lens technology that utilizes both multi-order diffractive surfaces and a diffractive Fresnel lens surface1–3 allows for the conception and development of future applications of the technology such as lightweight large aperture telescope primary lenses. Manufacturing methods being developed for this technology use glass compression molding to create its unique optical surface features. However, to enable the design and development of larger apertures using the MODE lens, it is necessary to allow segmentation due to the size constraints of current glass molding technology. Previous proceedings presented the effectiveness of the Kinematically-Engaged Yoke System (KEYS) to align the segments of a 0.24-m, PMMA, monochromatic, MODE-like lens (having no diffractive Fresnel lens features). The KEYS alignment system consists of ball bearings with which the step-like features of MODE lens segments kinematically engage with. In previous iterations of the KEYS, these ball bearings were mounted on ultra-fine screws that are adjusted radially with flexures that occupy space in the transverse plane (perpendicular to the MODE lens’s optical axis). We present a new iteration of KEYS in which these radially adjusting flexures have been modified to be located in planes that contain the MODE len’s optical axis. The alignment and optical performance of the MODE lens are evaluated using deflectometry in order to determine its current resolution of lens segment adjustment. Improvement of the KEYS will allow optical performance testing of the aligned lens. This version of KEYS will be used to assemble a 0.24-m, compression molded, glass, segmented MODE lens. © 2022 SPIE.Immediate accessThis item from the UA Faculty Publications collection is made available by the University of Arizona with support from the University of Arizona Libraries. If you have questions, please contact us at [email protected]

Developing the competence of organizing experiential activities for pre-service teachers – The case in Vietnam

Investing on human capital via enhancement of educational quality as one of the important factors to promote economic development all over the world. Basically, it is important to enhance pre-service teachers of primary education with necessary professional competences to implement teaching activities at primary schools. Based on relevant research on experiential activities, professional competence development for pre-service teachers of primary education and the general education curriculum in the case of Vietnam, the article develops a competency framework for organizing experiential learning activities for pre-service teachers of primary education in the context of education curriculum innovation; and simultaneously suggested fundamental solutions to improve pre-service teachers’ competence in organizing experiential activities. To achieve these above-mentioned goals, some research methods are used by the researchers including document analysis, pedagogical observation, and educational experience summarizing method

Experimentally evolved Staphylococcus aureus shows increased survival in the presence of Pseudomonas aeruginosa by acquiring mutations in the amino acid transporter, GltT.

When cultured together under standard laboratory conditions Pseudomonas aeruginosa has been shown to be an effective inhibitor of Staphylococcus aureus. However, P. aeruginosa and S. aureus are commonly observed in coinfections of individuals with cystic fibrosis (CF) and in chronic wounds. Previous work from our group revealed that S. aureus isolates from CF infections are able to persist in the presence of P. aeruginosa strain PAO1 with a range of tolerances with some isolates being eliminated entirely and others maintaining large populations. In this study, we designed a serial transfer, evolution experiment to identify mutations that allow S. aureus to survive in the presence of P. aeruginosa. Using S. aureus USA300 JE2 as our ancestral strain, populations of S. aureus were repeatedly cocultured with fresh P. aeruginosa PAO1. After eight coculture periods, S. aureus populations that survived better in the presence of PAO1 were observed. We found two independent mutations in the highly conserved S. aureus aspartate transporter, gltT, that were unique to evolved P. aeruginosa-tolerant isolates. Subsequent phenotypic testing demonstrated that gltT mutants have reduced uptake of glutamate and outcompeted wild-type S. aureus when glutamate was absent from chemically defined media. These findings together demonstrate that the presence of P. aeruginosa exerts selective pressure on S. aureus to alter its uptake and metabolism of key amino acids when the two are cultured together

Synthesis of the first dibenzo-4,12-dithio-8-azacrownophanes containing γ-arylpyridine subunit

[Figure not available: see fulltext.] Dibenzo-4,12-dithio-8-azacrownophanes containing γ-arylpyridine subunit and thiocrown fragment were synthesized in one step from 1,5-bis(2-acetylphenylsulfanyl)-3-oxapentane, aryl aldehydes, and ammonium acetate. © 2020, Springer Science+Business Media, LLC, part of Springer Nature

Application of Project-based Learning for Primary Teachers - A New Direction in Professional Training at Pedagogical Universities and Colleges in Vietnam

Teaching staffs in general and primary teachers in particular have been proven to contribute to great success of the comprehensive renovation process in the current Vietnamese education system. Significantly, pedagogical universities specialized in primary education should predominantly pay attention to the quality of training and meet the requirements of society. In the case of Tay Nguyen University in Vietnam, lecturer staffs involved in training of primary teachers have made great efforts in applying new teaching methods. Furthermore, it has been used effectively in many parts of the primary teacher training program is the project-based learning method. In this paper, in addition to general theories about the project-learning method, we will present the advantages of applying the teaching method in the primary teacher training program in general and in the "Crafts and Techniques" module in particular at Tay Nguyen University. Finally, discussion process of applying project-based learning and project evaluation methods of primary education students in teaching this module are preferred

Sero-prevalence of sars-cov-2 antibodies in high-risk populations in vietnam

As a response to the coronavirus disease 2019 (COVID-19) pandemic, Vietnam enforced strict quarantine, contact tracing and physical distancing policies resulting in one of the lowest numbers of individuals infected with severe acute respiratory syndrome-coronavirus-2 (SARS-CoV-2) globally. This study aimed to determine the prevalence of SARS-CoV-2 antibody positivity among high-risk populations in Vietnam. A prevalence survey was undertaken within four communities in Vietnam, where at least two COVID-19 cases had been confirmed. Participants were classified according to the location of exposure: household contacts, close contacts, community members, and healthcare workers (HCWs) responsible for treating COVID-19 cases. Participants completed a baseline questionnaire and SARS-CoV-2 IgG antibodies were quantified using a commercial assay. A total of 3049 community members and 149 health care workers consented to the study. Among 13 individuals who were seropositive (0.4%), five household contacts (5/27, 18.5%), one close contact (1/53, 1.9%), and seven community members (7/2954, 0.2%) had detectable SARS-CoV-2 antibodies. All HCWs were negative for SARS-CoV-2 antibodies. Participants were tested a median of 15.1 (interquartile range from 14.9 to 15.2) weeks after exposure. Our study found a low prevalence of SARS-CoV-2 antibodies in high-risk communities and healthcare workers in communities in Vietnam with known COVID-19 cases