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Optical systems use acousto-optic deflectors (AODs) mostly for fast angular scanning and spectral filtering of laser beams. However, AODs may transform laser light in much broader ways. When time-locked to the pulsing of low repetition rate laser amplifiers, AODs permit the holographic reconstruction of 1D and pseudo-two-dimensional (ps2D) intensity objects of rectangular shape by controlling the amplitude and phase of the light field at high (20–200 kHz) rates for microscopic light patterning. Using iterative Fourier transformations (IFTs), we searched for AOD-compatible holograms to reconstruct the given ps2D target patterns through either phase-only or complex light field modulation. We previously showed that phase-only holograms can adequately render grid-like patterns of diffraction-limited points with non-overlapping diffraction orders, while side lobes to the target pattern can be cured with an apodization mask. Dense target patterns, in contrast, are typically encumbered by apodization-resistant speckle noise. Here, we show the denoised rendering of dense ps2D objects by complex acousto-optic holograms deriving from simultaneous optimization of the amplitude and phase of the light field. Target patterns lacking ps2D symmetry, although not translatable into single holograms, were accessed by serial holography based on a segregation into ps2D-compatible components. The holograms retrieved under different regularizations were experimentally validated in an AOD random-access microscope. IFT regularizations characterized in this work extend the versatility of acousto-optic holography for fast dynamic light patterning.

Molecular biology, broadly defined as the investigation of complex biomolecules in the laboratory, is a rapidly advancing field and as such the technologies available to investigators are constantly evolving. This constant advancement has obvious advantages because it allows students and researchers to perform more complex experiments in shorter periods of time. One challenge with such a rapidly advancing field is that techniques that had been vital for students to learn how to perform are now not essential for a laboratory scientist. For example, while cloning a gene in the past could have led to a publication and form the bulk of a PhD thesis project, technology has now made this process only a step toward one of these larger goals and can, in many cases, be performed by a company or core facility. As teachers and mentors, it is imperative that we understand that the technologies we teach in the lab and classroom must also evolve to match these advancements. In this perspective, we discuss how the rapid advances in gene synthesis technologies are affecting curriculum and how our classrooms should evolve to ensure our lessons prepare students for the world in which they will do science.

La COVID-19 ha generado perjuicios económicos en todos los sectores productivos del país. Dicho efecto negativo trajo como consecuencia el incumplimiento en el pago de los créditos a microempresas incrementando los indicadores y niveles de morosidad de las denominadas entidades financieras de intermediación como lo son las cajas municipales en el país. Se hace énfasis en la importancia del tratamiento de indicadores relacionados a la dotación de recursos a sectores como el microempresarial, la calidad de las carteras y cómo ello repercute en la entidad financiera. Asimismo, esta investigación tiene como propósito poder comparar el nivel de morosidad antes y después de la pandemia. La investigación fue de corte longitudinal, enfoque deductivo, tipo pura o básica, nivel relacional y diseño no experimental. En cuanto a la población estuvo constituida por información perteneciente a las cajas municipales del Perú. Los datos se obtuvieron del repositorio de la Superintendencia de Banca, Seguros y de la AFP, y tienen una periodicidad mensual desde enero de 2018 hasta marzo de 2021. Para realizar la comprobación y verificación de la hipótesis del presente estudio se utilizó la prueba estadística t para igualdad de medias de muestras independientes verificando previamente los supuestos de normalidad y homogeneidad de varianzas. La investigación concluyó en que existen diferencias entre los niveles de morosidad antes y después del covid.

Introduction: Students in higher education courses need to practice vital groupwork skills that are increasingly relevant in today's collaborative workplace, which often occurs through small group coursework. Statement of the Problem: The process of forming small groups with students who are committed to the topic and goals is frequently problematic. Literature Review: We review the literature on the advantages and disadvantages of common group formation strategies, such as self-assembly and professor assignment. Teaching Implications: We discuss the use of a unique method of forming small groups in a university setting through a fun, interactive activity based on the classic "speed-dating" exercise. Conclusion: We recommend that educators consider the use of a speed-interviewing group formation strategy to allow groups to form based on similar topic interests and work styles.

Clinical knowledge, group facilitation skills, and cognitive congruence are considered important factors for the successful tutoring of Problem Based Learning sessions. In addition, the theory of Community of Practice has become an important tool to approach social learning and knowledge integration in medical education and organizational studies. More research is needed to link these two strands of research. We look at novice medical students' experiences and comparative reflections on student-tutors and clinician-tutors as facilitators of PBL sessions in a participatory, randomized cross-over design. Qualitative methodologies were used to probe the experiences of participants. In this study, the main factor for successful PBL sessions for first-year students was the creation of a nonhierarchical learning atmosphere, which starkly differentiated itself from the rigidity of a PBL structure organized around clinician-tutors and their hierarchically-imparted knowledge. In contrast, a more flexible strategy of student tutors and their constructive management of "not-knowing" enabled novice students to take steps on their own--of which they were highly appreciative, stressing how it allowed them to develop earlier autonomy with regard to PBL methodology, manage uncertainty, and create a shared identity as a community of learners.

Introduction Standard operating procedures (SOP), accessible to several laboratories, are essential for product verification. EU-JATC (European-Joint Action on Tobacco Control) SOP and the WHO TobLabNet (World Health Organization Tobacco Laboratories Network) SOP (SOP11) are available standard methodologies to measure nicotine, glycerol, and propylene glycol, and propose mass spectrometer (MS) as an alternative method to flame ionization detector (FID). This study conducted a comparison between FID and MS concentration results, following the MS method described in SOP11. Methods In May 2020, five test e-liquids in replicates (A-E) were prepared at the Istituto di Ricerche Farmacologiche Mario Negri and sent, with SOP 11, validation document and results datasheet to 32 different laboratories all over the world from WHO TobLabNet and EU-JATC (18 from JATC, ten from WHO TobLabNet and four academic laboratories). Among thirty-two independent laboratories that participated in the study, results were received from 30 laboratories. Results The e-liquids analyses, using the two approaches, were compared. Of the 30 laboratories surveyed, 21 utilized the FID approach exclusively, 7 opted for MS detection, and 2 employed both methods. The findings demonstrated that the gas chromatography-mass spectrometry (GC-MS) method offers comparable analytical capabilities regarding accuracy and precision for nicotine, glycerol, and propylene glycol to the FID approach. Through Pearson’s correlation test with r≃1 showing a positive correlation between GC-FID and GC-MS data, and the Student’s t-test, no significant differences between the two approaches were revealed, showing p>0.005 for almost all three analytes in all samples. Conclusions This study indicates that it is possible to apply the available EU-JATC SOP and the WHO TobLabNet SOP11 even in laboratories that do not have access to an FID, for example, to analyze flavors, trace compounds or carcinogenic, mutagenic, or toxic for reproduction (CMR) in electronic cigarette liquids.

A two-level data set can be structured in either long format (LF) or wide format (WF), and both have corresponding SEM approaches for estimating multilevel models. Intuitively, one might expect these approaches to perform similarly. However, the two data formats yield data matrices with different numbers of columns and rows, and their "cols : rows" is related to the magnitude of eigenvalue bias in sample covariance matrices. Previous studies have shown similar performance for both approaches, but they were limited to settings where "cols << rows" in both data formats. We conducted a Monte Carlo study to investigate whether varying "cols : rows" result in differing performances. Specifically, we examined the p:N ("cols : rows") effect on convergence and estimation accuracy in multilevel settings. Our findings suggest that (1) the LF approach is more likely to achieve convergence, but for the models that converged in both; (2) the LF and WF approach yield similar estimation accuracy; which is related to (3) differential "cols : rows" effects in both approaches; and (4) smaller ICC values lead to less accurate between-group parameter estimates.

Planning longitudinal studies can be challenging as various design decisions need to be made. Often, researchers are in search for the optimal design that maximizes statistical power to test certain parameters of the employed model. We provide a user-friendly Shiny app OptDynMo available at https://shiny.psychologie.hu-berlin.de/optdynmo that helps to find the optimal number of persons (N) and the optimal number of time points (T) for which the power of the likelihood ratio test (LRT) for a model parameter is maximal given a fixed budget for conducting the study. The total cost of the study is computed from two components: the cost to include one person in the study and the cost for measuring one person at one time point. Currently supported models are the cross-lagged panel model (CLPM), factor CLPM, random intercepts cross-lagged panel model (RI-CLPM), stable trait autoregressive trait and state model (STARTS), latent curve model with structured residuals (LCM-SR), autoregressive latent trajectory model (ALT), and the latent change score model (LCS).

This work addresses the evolution of Planning, Programming and Control of Production (PPCP) as essential activities of the company towards the insertion of environmental education. The approach is based on an exploratory research and a critical bibliographic revision. Two main objectives were established: i) a new way of production organization, by considering cleaner production from company utilities to production capacity, technology and outsourcing and ii) infrastructure changes related to market attendance and environmental education dissemination. Needs that arise can be grouped as follows: utilities adequacy, cleaner technologies and ecochains implementation; instruction and dissemination of environmental education; and necessity of the adoption of new paradigms.