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Equipping new teachers in today's society is a noble and challenging task. Of late, many additional licensing standards for teachers create additional responsibilities for universities that provide pedagogy, knowledge, and content for teacher candidates. Identification of best practices that support teacher candidates on the Educative Teacher Performance Assessment (edTPA) is of interest to many teacher education programs. The purpose of this research was to analyze whether incorporating a "mock edTPA" had beneficial results on the passage of the edTPA. This study spanned fourteen ten-week quarters and included 688 teacher candidates who were preparing to become certificated teachers at a university in Washington State. The questions that were posited were: (1) does a capstone class requiring a mock edTPA benefit students; and (2) which edTPA rubrics are the most challenging, and why are they challenging? This research study found that adding a mock edTPA prior to the student teaching experience did not produce a statistically significant difference in scores when compared to the group who received an embedded curriculum. When comparing the two different time periods, the passing rate was not significantly different and there was little difference in the mean scores of both groups.

Environmental stresses dramatically impact the balance between the production of photosynthetically derived energetic electrons and Calvin-Benson-Bassham cycle (CBBC) activity; an imbalance promotes accumulation of reactive oxygen species and causes cell damage. Hence, photosynthetic organisms have developed several strategies to route electrons toward alternative outlets that allow for storage or harmless dissipation of their energy. In this work, we explore the activities of three essential outlets associated with Chlamydomonas reinhardtii photosynthetic electron transport: (i) reduction of O2 to H2O through flavodiiron proteins (FLVs) and (ii) plastid terminal oxidases (PTOX) and (iii) the synthesis of starch. Real-time measurements of O2 exchange have demonstrated that FLVs immediately engage during dark-to-light transitions, allowing electron transport when the CBBC is not fully activated. Under these conditions, we quantified maximal FLV activity and its overall capacity to direct photosynthetic electrons toward O2 reduction. However, when starch synthesis is compromised, a greater proportion of the electrons is directed toward O2 reduction through both the FLVs and PTOX, suggesting an important role for starch synthesis in priming/regulating CBBC and electron transport. Moreover, partitioning energized electrons between sustainable (starch; energetic electrons are recaptured) and nonsustainable (H2O; energetic electrons are not recaptured) outlets is part of the energy management strategy of photosynthetic organisms that allows them to cope with the fluctuating conditions encountered in nature. Finally, unmasking the repertoire and control of such energetic reactions offers new directions for rational redesign and optimization of photosynthesis to satisfy global demands for food and other resources.

Iridescence is a taxonomically widespread form of structural coloration that produces often intense hues that change with the angle of viewing. Its role as a signal has been investigated in multiple species, but recently, and counter-intuitively, it has been shown that it can function as camouflage. However, the property of iridescence that reduces detectability is, as yet, unclear. As viewing angle changes, iridescent objects change not only in hue but also in intensity, and many iridescent animals are also shiny or glossy; these "specular reflections," both from the target and background, have been implicated in crypsis. Here, we present a field experiment with natural avian predators that separate the relative contributions of color and gloss to the "survival" of iridescent and non-iridescent beetle-like targets. Consistent with previous research, we found that iridescent coloration, and high gloss of the leaves on which targets were placed, enhance survival. However, glossy targets survived less well than matt. We interpret the results in terms of signal-to-noise ratio: specular reflections from the background reduce detectability by increasing visual noise. While a specular reflection from the target attracts attention, a changeable color reduces the signal because, we suggest, normally, the color of an object is a stable feature for detection and identification. [ABSTRACT FROM AUTHOR]

It has been postulated that during human fetal development, all cells of the lung epithelium derive from embryonic, endodermal, NK2 homeobox 1-expressing ([NKX2-1.sup.+]) precursor cells. However, this hypothesis has not been formally tested owing to an inability to purify or track these progenitors for detailed characterization. Here we have engineered and developmentally differentiated [NKX2-1.sup.GFP] reporter pluripotent stem cells (PSCs) in vitro to generate and isolate human primordial lung progenitors that express NKX2-1 but are initially devoid of differentiated lung lineage markers. After sorting to purity, these primordial lung progenitors exhibited lung epithelial maturation. In the absence of mesenchymal coculture support, this [NKX2-1.sup.+] population was able to generate epithelial-only spheroids in defined 3D cultures. Alternatively, when recombined with fetal mouse lung mesenchyme, the cells recapitulated epithelial-mesenchymal developing lung interactions. We imaged these progenitors in real time and performed time-series global transcriptomic profiling and single-cell RNA sequencing as they moved through the earliest moments of lung lineage specification. The profiles indicated that evolutionarily conserved, stage-dependent gene signatures of early lung development are expressed in primordial human lung progenitors and revealed a [CD47.sup.hi][CD26.sup.lo] cell surface phenotype that allows their prospective isolation from untargeted, patient-specific PSCs for further in vitro differentiation and future applications in regenerative medicine., Introduction Little is known about the early stages of human lung development, preventing an understanding of whether successful healing from adult lung injury involves recapitulation of embryonic mechanisms and limiting [...]