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  1. Abstract

    Microelectronic devices can directly communicate with biology, as electronic information can be transmitted via redox reactions within biological systems. By engineering biology’s native redox networks, we enable electronic interrogation and control of biological systems at several hierarchical levels: proteins, cells, and cell consortia. First, electro-biofabrication facilitates on-device biological component assembly. Then, electrode-actuated redox data transmission and redox-linked synthetic biology allows programming of enzyme activity and closed-loop electrogenetic control of cellular function. Specifically, horseradish peroxidase is assembled onto interdigitated electrodes where electrode-generated hydrogen peroxide controls its activity.E. coli’s stress response regulon,oxyRS, is rewired to enable algorithm-based feedback control of gene expression, including an eCRISPR module that switches cell-cell quorum sensing communication from one autoinducer to another—creating an electronically controlled ‘bilingual’ cell. Then, these disparate redox-guided devices are wirelessly connected, enabling real-time communication and user-based control. We suggest these methodologies will help us to better understand and develop sophisticated control for biology.

     
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  2. Free, publicly-accessible full text available December 15, 2024
  3. Abstract

    Current research underscores that there are only a few evidence-based programs that teach STEM (science, technology, engineering, and mathematics) as part of their curriculum, especially for autistic students. Even fewer programs focus on engineering and design learning. Hence, we developed an informal afterschool maker program to develop autistic and non-autistic students’ interests in engineering to understand their experiences learning STEM concepts and values while applying the engineering mindset to develop projects. This qualitative study aimed to explore and understand students’ experiences participating in STEM activities in the maker club. We interviewed twenty-six students (seventeen autistic and nine non-autistic), nine teachers, and thirteen parents representing diverse cultural and socio-economic backgrounds across three public middle schools in a large urban metropolitan city between 2018 and 2019. Our thematic analysis yielded four themes:(1) active participation in STEM; (2) curiosity about STEM topics, concepts, and practices, (3) capacity-building to engage in STEM learning; and 4) understanding of the importance of STEM education in daily life.The results of this study enabled us to understand that students were deeply engaged with the content and curriculum of our program, expanded their knowledge base about scientific concepts, used engineering-specific scientific terminologies, and engaged with the engineering design process to conceptualize, test, improvise, and problem-solve. Furthermore, this afterschool engineering education program created a safe, nurturing, and stimulating environment for students to build engineering readiness skills.

     
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  4. Abstract

    Autologous cell therapy depends on T lymphocyte expansion efficiency and is hindered by suboptimal interactions between T cell receptors (TCR) and peptide‐MHC molecules. Various artificial antigen presenting cell systems that enhance these interactions are often labor‐intensive, fabrication costly, highly variable, and potentially unscalable toward clinical setting. Here, 3D centrifugation‐enabled priming of T cell immune‐synapse junctions is performed to generate tight T cell–Dynabead aggregates at a rate 200‐fold faster than that of conventional 24‐h bulk shaking. Furthermore, by forming T cell–Dynabead aggregates in the starting culture, two‐ to sixfold greater T cell expansion is achieved over conventional T cell expansion for cancer patient‐derived primary T cells while limiting over‐activation. Creating 3D T cell–Dynabead aggregates as the “booster” material enables highly efficient polyclonal T cell expansion without the need for complex surface modification of artificial antigen‐presenting cells (APCs). This method can be modularly adapted to existing T cell expansion processes for various applications, including adoptive cell therapies (ACTs).

     
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    Free, publicly-accessible full text available December 1, 2024
  5. Abstract

    Small-scale interplanetary magnetic flux ropes (SMFRs) are similar to ICMEs in magnetic structure, but are smaller and do not exhibit coronal mass ejection plasma signatures. We present a computationally efficient and GPU-powered version of the single-spacecraft automated SMFR detection algorithm based on the Grad–Shafranov (GS) technique. Our algorithm can process higher resolution data, eliminates selection bias caused by a fixed 〈B〉 threshold, has improved detection criteria demonstrated to have better results on an MHD simulation, and recovers full 2.5D cross sections using GS reconstruction. We used it to detect 512,152 SMFRs from 27 yr (1996–2022) of 3 s cadence Wind measurements. Our novel findings are the following: (1) the SMFR filling factor (∼ 35%) is independent of solar activity, distance to the heliospheric current sheet, and solar wind plasma type, although the minority of SMFRs with diameters greater than ∼0.01 au have a strong solar activity dependence; (2) SMFR diameters follow a log-normal distribution that peaks below the resolved range (≳104km), although the filling factor is dominated by SMFRs between 105and 106km; (3) most SMFRs at 1 au have strong field-aligned flows like those from Parker Solar Probe measurements; (4) the radial density (generally ∼1 detected per 106km) and axial magnetic flux density of SMFRs are higher in faster solar wind types, suggesting that they are more compressed. Implications for the origin of SMFRs and switchbacks are briefly discussed. The new algorithm and SMFR dataset are made freely available.

     
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  6. Free, publicly-accessible full text available November 1, 2024
  7. Dithienylethenes (DTEs) are a promising class of organic photoswitches that can be used to create crystalline solids with properties controlled by light. However, the ability of DTEs to adopt multiple conformations, only one of which is photoactive, complicates the rational design of these materials. Herein, the synthesis and structural characterization of 19 crystalline solids containing a single DTE molecule are described. A novelDDanalysis of the molecular geometries obtained from rotational potential energy surface calculations and the ensemble of experimental structures were used to construct a crystal landscape for DTE. Of the 19 crystal structures, 17 contained photoinactive DTE rotamers and only 2 were photoactive. These results highlight the challenges associated with the design of these materials. Overall, theDDanalysis described herein provides rapid, effective and intuitive means of linking the molecular structure to photoactivity that could be applied more broadly to afford a general strategy for producing photoactive diarylethene-based crystalline solids.

     
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    Free, publicly-accessible full text available November 1, 2024
  8. Free, publicly-accessible full text available October 12, 2024
  9. Abstract

    Organofunctionalized tetranuclear clusters [(MIICl)2(VIVO)2{((HOCH2CH2)(H)N(CH2CH2O))(HN(CH2CH2O)2)}2] (1, M=Co,2: M=Zn) containing an unprecedented oxometallacyclic {M2V2Cl2N4O8} (M=Co, Zn) framework have been prepared by solvothermal reactions. The new oxo‐alkoxide compounds were fully characterized by spectroscopic methods, magnetic susceptibility measurement, DFT and ab initio computational methods, and complete single‐crystal X‐ray diffraction structure analysis. The isostructural clusters are formed of edge‐sharing octahedral {VO5N} and trigonal bipyramidal {MO3NCl} units. Diethanolamine ligates the bimetallic lacunary double cubane core of1and2in an unusual two‐mode fashion, unobserved previously. In the crystalline state, the clusters of1and2are joined by hydrogen bonds to form a three‐dimensional network structure. Magnetic susceptibility data indicate weakly antiferromagnetic interactions between the vanadium centers [Jiso(VIV−VIV)=−5.4(1); −3.9(2) cm−1], and inequivalent antiferromagnetic interactions between the cobalt and vanadium centers [Jiso(VIV−CoII)=−12.6 and −7.5 cm−1] contained in1.

     
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    Free, publicly-accessible full text available October 23, 2024