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This study examined the impact of a National Science Foundation-funded support program for academically promising STEM students from low-income backgrounds. The program operates as a collaborative consortium, bringing together three public community colleges and one private university, to support the retention and graduation of program scholars. Using propensity score matching, we compared 169 program scholars to 169 matched non-scholars with similar demographic, academic, and financial characteristics ( M_age= 24.82 years; 41% female; 60% students of color). Participation in the program was associated with favorable academic outcomes, with large to moderate effect sizes. Specifically, program scholars had significantly higher cumulative and STEM-specific grade point averages than their non-scholar counterparts. They also completed significantly more STEM courses and were less likely to withdraw from college than non-scholars. These findings underscore the potential of comprehensive and equity-oriented approaches to STEM education in facilitating academic success for STEM students, particularly those from low-income backgrounds.

 

Multispectral biological fluorescence microscopy has enabled the identification of multiple targets in complex samples. The accuracy in the unmixing result degrades (i) as the number of fluorophores used in any experiment increases and (ii) as the signal-to-noise ratio in the recorded images decreases. Further, the availability of prior knowledge regarding the expected spatial distributions of fluorophores in images of labeled cells provides an opportunity to improve the accuracy of fluorophore identification and abundance.

We propose a regularized sparse and low-rank Poisson regression unmixing approach (SL-PRU) to deconvolve spectral images labeled with highly overlapping fluorophores which are recorded in low signal-to-noise regimes. First, SL-PRU implements multipenalty terms when pursuing sparseness and spatial correlation of the resulting abundances in small neighborhoods simultaneously. Second, SL-PRU makes use of Poisson regression for unmixing instead of least squares regression to better estimate photon abundance. Third, we propose a method to tune the SL-PRU parameters involved in the unmixing procedure in the absence of knowledge of the ground truth abundance information in a recorded image. By validating on simulated and real-world images, we show that our proposed method leads to improved accuracy in unmixing fluorophores with highly overlapping spectra.

The source code used for this article was written in MATLAB and is available with the test data at https://github.com/WANGRUOGU/SL-PRU.

 

Hydrogen-atom (H-atom) transfer at the surface of heterogeneous metal oxides has received significant attention owing to its relevance in energy conversion and storage processes. Here, we present the synthesis and characterization of an organofunctionalized polyoxovanadate cluster, (calix)V6O5(OH2)(OMe) 8 (calix = 4- tert -butylcalix[4]arene). Through a series of equilibrium studies, we establish the BDFE(O–H) avg of the aquo ligand as 62.4 ± 0.2 kcal mol −1 , indicating substantial bond weaking of water upon coordination to the cluster surface. Subsequent kinetic isotope effect studies and Eyring analysis indicate the mechanism by which the hydrogenation of organic substrates occurs proceeds through a concerted proton–electron transfer from the aquo ligand. Atomistic resolution of surface reactivity presents a novel route of hydrogenation reactivity from metal oxide surfaces through H-atom transfer from surface-bound water molecules. 

We report accelerated rates of oxygen-atom transfer from a polyoxovanadate–alkoxide cluster following functionalization with a 4- tert butylcalix[4]arene ligand. Incorporation of this electron withdrawing ligand modifies the electronics of the metal oxide core, favoring a mechanism in which the rate of oxygen-atom transfer is limited by outer-sphere electron transfer. 

Discrete monuments remain in the domain of the symbolic, land as mnemonic shifts to a more materialist commemorative praxis. This paper proposes a turn toward land as mnemonic of Black freedom struggle and place‐making. Reviewing the scholarship on memoryscapes, I show that the critical insights of Black ecologies and geographies scholarship has moved further than traditional scholarship and offers multiple openings for new monuments and commemorative practices in honor of Black life. Black socio‐ecologies scholarship centralizes the place‐based epistemologies, spatial histories, and experiences of Black communities and clarifies the form and function of land or plots as mnemonics of the Black freedom struggle, place‐making practices, and spatial epistemologies. Black plots are, therefore, ideal for orienting a new mode of Black commemoration. While much of the paper centers monuments to Black people, if Black commemoration is foregrounded in abolitionists thinking and practices, such memorialization must grapple with the histories of Indigenous dispossession and settler‐colonialism. The paper concludes with a consideration of what the argument for land as mnemonic of Black freedom struggle and place‐making might mean for future avenues of research.