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Current conservative assaults on Critical Race Theory (CRT) in education contend that elementary and secondary teachers and teacher education faculty are not only 'teaching CRT', but also hatred of white people and of 'America'. This article is based on a study that used CRT analytical tools and narrative inquiry to examine pre- and in-service teachers' understanding of CRT bans, race, and racism. Through individual and focus group interviews with racially and ethnically diverse pre- and in-service teachers, manifestations of anti-intellectualism and (dis)ease emerged in participant responses to questions about their perceptions of, and evidence-based knowledge about, CRT, as well as race and racism. Implications call for a radical rethinking of teacher preparation by helping teachers develop epistemic humility, curiosity, and courage. [ABSTRACT FROM AUTHOR]

The Omicron (B.1.1.529) variant of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) was initially identified in November 2021 in South Africa and Botswana, as well as in a sample from a traveller from South Africa in Hong Kong1,2. Since then, Omicron has been detected globally. This variant appears to be at least as infectious as Delta (B.1.617.2), has already caused superspreader events3, and has outcompeted Delta within weeks in several countries and metropolitan areas. Omicron hosts an unprecedented number of mutations in its spike gene and early reports have provided evidence for extensive immune escape and reduced vaccine effectiveness2,4–6. Here we investigated the virus-neutralizing and spike protein-binding activity of sera from convalescent, double mRNA-vaccinated, mRNA-boosted, convalescent double-vaccinated and convalescent boosted individuals against wild-type, Beta (B.1.351) and Omicron SARS-CoV-2 isolates and spike proteins. Neutralizing activity of sera from convalescent and double-vaccinated participants was undetectable or very low against Omicron compared with the wild-type virus, whereas neutralizing activity of sera from individuals who had been exposed to spike three or four times through infection and vaccination was maintained, although at significantly reduced levels. Binding to the receptor-binding and N-terminal domains of the Omicron spike protein was reduced compared with binding to the wild type in convalescent unvaccinated individuals, but was mostly retained in vaccinated individuals.Sera from unvaccinated, vaccinated, and previously infected and vaccinated individuals show reduced neutralizing and spike protein-binding activity towards the Omicron (B.1.1.529) variant of SARS-CoV-2 compared to other variants. [ABSTRACT FROM AUTHOR]

We construct energy-optimized resonating valence bond wave functions as a means to sketch out the zero-temperature phase diagram of the square-lattice quantum Heisenberg model with competing nearest- (J1) and next-nearest-neighbor (J2) interactions. Our emphasis is not on achieving an accurate representation of the magnetically disordered intermediate phase (centered on a relative coupling g=J2/J1~½ and whose exact nature is still controversial) but on exploring whether and how the Marshall sign structure breaks down in the vicinity of the phase boundaries. Numerical evaluation of two- and four-spin correlation functions is carried out stochastically using a worm algorithm that has been modified to operate in either of two modes: one in which the sublattice labeling is fixed beforehand and another in which the worm manipulates the current labeling so as to sample various sign conventions. Our results suggest that the disordered phase evolves continuously out of the (π,π) Néel phase and largely inherits its Marshall sign structure; on the other hand, the transition from the magnetically ordered (π,0) phase is strongly first order and involves an abrupt change in the sign structure and spatial symmetry as the result of a level crossing. [ABSTRACT FROM AUTHOR]

High-stress silicon nitride nanostrings are a promising system for sensing applications because of their ultra-high mechanical quality factors (Qs). By performing thermomechanical calibration across multiple vibrational modes, we are able to assess the roles of the various dissipation mechanisms in these devices. Specifically, we possess a set of nanostrings in which all measured modes fall upon a single curve of peak displacement versus frequency. This allows us to rule out bulk bending and intrinsic loss mechanisms as dominant sources of dissipation and to conclude that the most significant contribution to dissipation in high-stress nanostrings occurs at the anchor points. [ABSTRACT FROM AUTHOR]

Inspired by recent experiments on 3He films between one and two atoms thick, we consider a bilayer Hubbard model on a triangular lattice. Our results are obtained in the framework of a cluster dynamical mean-field calculation with a quantum Monte Carlo impurity solver. For appropriate model parameters, we observe an enhancement of the effective mass as the first layer approaches integer filling and the second remains only partially filled. At finite temperatures, this increase of the effective mass-or, equivalently, the decrease of the coherence temperature-leads to a crossover to a state where the first-layer fermions localize, drop out of the Luttinger volume, and generate essentially free local moments. This finite temperature behavior is shown to be robust against the cluster size above some critical temperature. The zero-temperature phase diagram, however, depends on the cluster topology. In particular, for clusters with an even number of unit cells, the growth of the effective mass is cut off by a first-order, orbital-selective Mott transition. [ABSTRACT FROM AUTHOR]

A person experiencing more than one medical condition may have ambiguous clinical presentation. ITP is a serious autoimmune disease with little epidemiological evidence on its burden, risk factors, and comorbidities. Using the United Kingdom general practice research database, we conducted a 14 years population-based case control-type study to explore medical conditions more likely to cooccur with ITP and their temporal relationship in association with ITP. ITP patients were matched to non-ITP on practice, age, gender, and follow-up period. Potential comorbidities were represented by patients' medical information at the preferred term level of the MedDRA international classification. As well as death (OR = 60.0; 95% CI [4.47-806.0]) and known clinical signs and symptoms of ITP, ITP is associated with considerable number of medical conditions. The association between ITP and some of these conditions is apparent both before and after ITP diagnosis. Specific targeted studies can now be setup to reexamine observed associations. [ABSTRACT FROM AUTHOR]

In vivo transmittance and reflectance spectra from 280 to 700 nm were obtained from 14 species for macroalgae to quantitatively compare to what extent species from different divisions, of dissimilar functional forms and with various cell-wall constituents, absorb incident irradiance. Absorptance of photosynthetically active radiation (PAR) ranged from 64 to 92%. Ultraviolet radiation (UV-R) absorptances were found to be higher than absorptances of PAR for all species in both ultraviolet-B radiation (UV-BR) and ultraviolet-A radiation (UV-AR) portions of the spectrum. Transmittance of UV-BR through macroalgal thalli was markedly low compared with other wavelength ranges and is likely due to photoprotective UV-absorbing compounds within macroalgal cells. Reflectance of irradiance off algal thalli was higher than transmittance for all calcified species and for 57% of uncalcified species. Irradiance reflected from the surface of macroalgae accounted for as little as 7% and as much as 23% of incident PAR. Irradiance reflected off of calcified species exposed their chloroplasts to a diminished irradiance environment than species with higher absorptances. Reflectance needs to be quantified for accurate, comparable estimates of quantum yield via oxygen evolution and electron transport rates via chlorophyll fluorescence. Three sympatric members of the order Dictyotales (class Phaeophyceae) differed significantly in their photosynthetic performance. Sun to shade type P vs I curve parameters were strongly correlated with decreased absorptances in Dictyota acutiloba vs Padina japonica and Stypopodium hawaiiensis. Elevated thallus absorptance in D. acutiloba coupled with postabsorbance mechanisms of dissipating photoinhibitory irradiance may contribute to elevated productivity for this species. [ABSTRACT FROM AUTHOR]

During the past decade, the relative abundance of the brown macroalgae Dictyota spp. has been high in the Florida Keys. Recent studies have shown that members of this genus successfully reproduce via vegetative fragmentation. To investigate the importance of fragmentation on the reef community, this study examined: (1) the degree of epiphytism on benthic organisms, (2) the rate of fragment production through fish foraging activities, (3) the likelihood of fragment entanglement, and (4) the fragment attachment and success rate. It was found that reef fish contributed substantially to the fragment pool; furthermore, most fish-produced fragments produced rhizoids and attached to sand grains within 24 h in the field. Fragments of Dictyota spp. most commonly became entangled around and then attached themselves to the green alga Halimeda tuna, and other Dictyota spp. These results suggest that vegetative fragmentation of Dictyota spp. plays an important role in the changing community structure on the Florida Keys reef tract. [ABSTRACT FROM AUTHOR]

Analysis of absorbance spectra of the red alga, Ahnfeltiopsis concinna, revealed the capacity of tissues from the canopy and understory to respond to changes in the intensity of photosynthetically active radiation. No differences in photoacclimation responses were observed in the experiments performed with A. concinna under PAR-only, PAR UV-A, and PAR UV-A UV-B treatments. In situ, photoacclimation capacities were manifested as marked alterations in pigmentation for tissues from canopy to understory microsites in individual thalli of this dense tropical turf. This phenotypic adjustment is dynamic and recovery from irradiance stress induced by canopy removal simulating herbivory or bleaching events is complete within 29 days. In vivo absorbance spectra allowed simultaneous observation of multiple pigment pools and monitoring photoac-climation changes over the course of days in this alga. Insight into the cascade of photoacclimation events was revealed by concurrent measurement of pigments and photosynthetic performance. Overall, acclimation from a sun to shade or shade to sun states proceeded faster for degradative than for synthetic processes. Specifically, phycobilin degradation in tissues from understory microsites exposed to high photon flux density (PFD) was faster than phycobilin synthesis in tissues from canopy microsites exposed to low PFD. Additionally, levels of phycoerythrin changed to a greater relative extent than did shifts of compensation or saturation irradiance thresholds for photosynthesis in acclimation from shade to sun conditions. Compensation and saturation irradiances changed to a greater relative extent than did levels of phycoerythrin in acclimation from sun to shade conditions. Lastly, carotenoid and putative mycosporine amino acid absorbances adjusted in response to changes in quantity of incident photon flux regardless of light quality (PAR, UV-B, UV-A). This suggests a similar signal transduction mechanism or other metabolic linkages in this photoacclimation mechanism. [ABSTRACT FROM AUTHOR]

We demonstrate by experiment that, in addition to the local surface slope, local surface elevation can also be directly measured using the refracted light beam traversing an air-water interface, thus showing the feasibility of a new surface slope and wave height amplitude gauge for use in studying water waves. We have achieved surface height resolutions as small as 40 μm for the range of surface wavelengths λ ∼ 1.2-2.4 cm used in the present experiments. This measurement principle is readily adaptable to waves of different scale. The available dynamic range defined by the ratio of maximum wave amplitude to minimum resolvable amplitude need only be limited by the useful dynamic range of the photodetector when matched to a laser of suitable frequency and sufficient power. [ABSTRACT FROM AUTHOR]

The supposition that the lower limb expands uniformly in circumference during venous occlusion has been investigated. The 3 compartments of the calf were found to expand to differing degrees depending on the volume of muscle within the compartment. The effect of this phenomenon on the measurement of venous outflow and capacitance using an overlapping strain gauge was assessed. When using an overlapping strain gauge, the anatomical site of overlap was found to alter the measured values of outflow and capacitance by as much as 50%. These errors do not arise with strain gauges designed to fit a small range of limb circumferences, so that no overlap occurs. The reproducibility of plethysmography may be enhanced by attention to the site and degree of overlap of gauges which are designed to fit all sizes of limb. Technicians performing venous occlusion plethysmography should be aware of these variations, so that the examination technique can be standardized. [ABSTRACT FROM AUTHOR]