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Dielectric electrostatic capacitors1, because of their ultrafast charge-discharge, are desirable for high-power energy storage applications. Along with ultrafast operation, on-chip integration can enable miniaturized energy storage devices for emerging autonomous microelectronics and microsystems2-5. Moreover, state-of-the-art miniaturized electrochemical energy storage systems-microsupercapacitors and microbatteries-currently face safety, packaging, materials and microfabrication challenges preventing on-chip technological readiness2,3,6, leaving an opportunity for electrostatic microcapacitors. Here we report record-high electrostatic energy storage density (ESD) and power density, to our knowledge, in HfO2-ZrO2-based thin film microcapacitors integrated into silicon, through a three-pronged approach. First, to increase intrinsic energy storage, atomic-layer-deposited antiferroelectric HfO2-ZrO2 films are engineered near a field-driven ferroelectric phase transition to exhibit amplified charge storage by the negative capacitance effect7-12, which enhances volumetric ESD beyond the best-known back-end-of-the-line-compatible dielectrics (115 J cm-3) (ref. 13). Second, to increase total energy storage, antiferroelectric superlattice engineering14 scales the energy storage performance beyond the conventional thickness limitations of HfO2-ZrO2-based (anti)ferroelectricity15 (100-nm regime). Third, to increase the storage per footprint, the superlattices are conformally integrated into three-dimensional capacitors, which boosts the areal ESD nine times and the areal power density 170 times that of the best-known electrostatic capacitors: 80 mJ cm-2 and 300 kW cm-2, respectively. This simultaneous demonstration of ultrahigh energy density and power density overcomes the traditional capacity-speed trade-off across the electrostatic-electrochemical energy storage hierarchy1,16. Furthermore, the integration of ultrahigh-density and ultrafast-charging thin films within a back-end-of-the-line-compatible process enables monolithic integration of on-chip microcapacitors5, which can unlock substantial energy storage and power delivery performance for electronic microsystems17-19.

This paper presents a regulating Hybrid Switched Capacitor Converter (HSCC) topology suitable for high conversion ratio Point-of-Load (PoL) applications, specifically targeting 48 V to 1 V power delivery in space-based high-performance computing systems, where size and weight are important considerations, along with device de-rating for radiation tolerance. The proposed topology merges an initial 2:1 switched capacitor conversion stage with a recently developed symmetric dual inductor hybrid (SDIH) conversion stage, reaping benefits of both. The SDIH stage offers reduced component count and an excellent switch stress figure of merit, while the initial 2:1 voltage reduction stage significantly reduces the volume of flying capacitors, enabling compact size and low weight. A high density gate drive solution is also presented, using a minimal number of driver ICs without compromising on driving capability. A preliminary hardware prototype demonstrates this topology's feasibility while employing de-rated gallium nitride (GaN) switches to safeguard against radiation total ionizing dose (TID) and single event effects (SEE). This prototype achieves a very high measured power density of 2,020 W/inch3 (123.3 kW/liter) while performing 48 V to 1 V conversion and switching at 1 MHz.

Music-based speech language interventions have shown promise to support young children with autism, other speech and language deficits, and Dual Language Learners (also known as DLL, English Language Learners, or ELL). Online edtech learning programs may produce greater positive outcomes for children by including parents as mediators of the intervention. This study measured the preliminary effectiveness of Sing and Speak 4 Kids (SS4Kids), a music-based online speech and language development game, administered to 26 children ages 2-6 years old with or at risk for a diagnosis of autism, other speech and language deficits or DLL. The children were trained in early intervention settings across 4-6 sessions over a 2-week period in one of three group conditions: (a) teacher only in clinic; (b) parent only at home; (c) both teacher + parent. Measurement of verbal production of target words in pre- and post-training sessions showed that trained words significantly improved from pre-test to post-test Additionally, there was no effect of different group conditions (teacher only vs. parent only vs. both teacher + parent) on children's performance. Results suggest that the SS4Kids program is an effective music-based speech and language training method for supporting target word production in young children across a two week timespan. Importantly, the results also found that group conditions did not influence the improvement, confirming effectiveness of both clinic and home-based parent mediation. During a time when traditional in-person intervention services may be restricted, the current work provides cautious but emerging evidence of the effectiveness of an online edtech evidence-based practice to support the speech and language outcomes for a variety of children in early intervention.

While creativity is an established driver of profit for firms and success for individuals, not all situations are ideal for maximizing creativity. In this work, we establish a framework of ways that creators can deliberately reduce novelty in their works to make them more successful. The first way, permanent novelty reduction (PNR), is where creators decrease novelty in key aspects of their final product to make it more amenable to consumers or gatekeepers. The second way, temporary novelty reduction (TNR), involves strategically decreasing novelty in the short term to overcome environmental or functional resistance to novelty, often leading to a more creative product in the long term. Together, these two categories of novelty reduction support a new theoretical perspective: novelty reduction can play a critical role in the creative process. We develop this perspective by examining James Cameron and his team’s creative decisions during the making of one of the most successful films of all time, Avatar. [ABSTRACT FROM AUTHOR]

Racial-ethnic and low-income youth have differential access to key educational resources that promote learning and college readiness. College readiness programs provide activities, resources, and experiences that support learning. Yet little is known about the influence of adults and peers in shaping students' beliefs and expectations as learners. This study examined the extent to which GEAR UP adolescent self-regulated learning was influenced by perceptions of adult and peer behavioral expectations. Among the 118 adolescent participants, perceived behavioral expectations of a parent or guardian was found to be the strongest determinant of self-regulated learning. Implications and directions for future research are discussed.

Most defects causing retinal degeneration in retinitis pigmentosa (RP) are rod-specific mutations, but the subsequent degeneration of cones, which produces loss of daylight vision and high-acuity perception, is the most debilitating feature of the disease. To understand better why cones degenerate and how cone vision might be restored, we have made the first single-cell recordings of light responses from degenerating cones and retinal interneurons after most rods have died and cones have lost their outer-segment disk membranes and synaptic pedicles. We show that degenerating cones have functional cyclic-nucleotide-gated channels and can continue to give light responses, apparently produced by opsin localized either to small areas of organized membrane near the ciliary axoneme or distributed throughout the inner segment. Light responses of second-order horizontal and bipolar cells are less sensitive but otherwise resemble those of normal retina. Furthermore, retinal output as reflected in responses of ganglion cells is less sensitive but maintains spatiotemporal receptive fields at cone-mediated light levels. Together, these findings show that cones and their retinal pathways can remain functional even as degeneration is progressing, an encouraging result for future research aimed at enhancing the light sensitivity of residual cones to restore vision in patients with genetically inherited retinal degeneration.

As a result of their soft-charging and soft-switching capabilities, resonant switched-capacitor (ReSC) converters can achieve higher efficiencies and power densities than pure switched-capacitor (SC) converters. However, the terminal capacitors (i.e, the input and output capacitors) still consume a large volume in ReSC converters and represent the new bottleneck for converter miniaturization. Theoretically, when the terminal capacitances are reduced, an optimum clocking scheme that preserves multi-resonant operation can be calculated. In practice, this optimal operating point may not be precisely obtained due to circuit parasitics, passive component tolerance and derating. This paper demonstrates a closed-loop hysteretic control method that can dynamically track the zero current switching (ZCS) operating point and allow for a reduction in terminal filtering capacitors via multi-resonant operation. A 48-to-24-V ReSC converter prototype is designed and constructed to verify the effectiveness of the proposed control method. The controller is demonstrated to successfully track the ZCS operating point, enabling over 70% reduction in terminal capacitor volume. In the case of reduced terminal capacitances, the controller achieves up to 44% reduction in power loss compared with the conventional open-loop control without ZCS autotuning.

This paper proposes an efficient and compact hybrid switched-capacitor (SC) converter for direct 48-to-1-V power conversion in data centers. The proposed topology can be viewed as a 2-to-1 SC converter merged with two 8-to-1 series-capacitor-buck (SCB) modules through two switching buses. Different from the conventional DC bus architecture, the switching bus architecture removes the bulky DC bus capacitors and reduces the number of switches. Compared with existing 48-to-1-V hybrid SC demonstrations, the proposed converter achieves the highest SC stage conversion ratio with the lowest normalized switch volt-ampere (VA) rating, which promises lightened conversion burden on the following buck stage and reduced switch stress. A hardware prototype is designed, constructed and tested up to 500-A output current, achieving 94.7% peak power stage efficiency, 86.4% full-load efficiency and 464-W/in3 power density.

This work introduces the symmetric dual inductor hybrid (SDIH) dc-dc converter topology, which is suitable for large conversion ratios where regulation is required, such as direct 48 V to point-of-load (PoL) applications. A dickson-type switched capacitor network is used to effectively produce two interleaved PWM outputs with a greatly reduced voltage amplitude relative to the input voltage, allowing the subsequent magnetic volume to be reduced while retaining modest switching frequencies. Distinct from related variations, part count is significantly reduced while both even and odd order switched capacitor networks can be used with straightforward split-phase control; allowing either network type to achieve complete soft-charging of all flying capacitors. Additionally, charge flow is uniformly distributed through all elements, with equal capacitor and inductor values being preferred. Subsequently this topology is expected to simplify component selection, improve electrical and thermal performance, and reduce cost. Furthermore, analysis is presented that calculates precise phase durations without making small ripple assumptions, revealing up to a 75% timing error in cases where either inductor or capacitor ripple is ignored. Finally, a discrete prototype validates this analysis and demonstrates very high measured power densities of 1,029 W/in$^{3}$, 754 W/in$^{3}$, and 663 W/in$^{3}$ for 48 V input and regulated output voltages of 3 V, 2 V, and 1 V, respectively, while switching at a frequency of 750 kHz.

This work presents a general analytical framework enabling large-signal characterization of resonant switched-capacitor (ReSC) power converters that accounts for passive component voltage and current ripple, for operation at and above resonance. From this, appropriate phase durations for minimized rms currents are derived, in addition to expressions for total passive component volume using an intuitive peak energy method. An example hardware prototype validates both the derived waveforms and timings—as well as total passive volume—through three comparable hardware configurations, one of which minimizes passive component volume. In addition, the proposed technique formulates analytical expressions for both rms currents and peak blocking voltages, facilitating refined loss estimation and component selection. Subsequent calculation of the large-signal Volt–Amp (VA) switch stress metric allows a more accurately quantified trade-off between active and passive components compared to prior work, which has not fully accounted for ripple. Four common ReSC topologies are exemplified throughout, with topology specific parameters documented for reference.

The flying capacitor multilevel (FCML) converter is an attractive candidate for dc/dc step-up and step-down applications due to its relatively low switch stress and greatly reduced inductor volume. It can be operated in either a regulating pulse width modulated (PWM) or fixed-ratio resonant mode. For fixed-ratio operation, the FCML converter is capable of achieving multiple rational conversion ratios (up to a maximum of N:1) with the same switch-capacitor network simply by changing the gating signals of its switches. In addition, the inductance requirement can be further reduced compared to regulated operation, while switching losses at resonance can be mitigated due to the presence of soft-switching. However, there is limited prior analysis of higher level-count (N\geq 3) fixed-ratio FCML converters operating at resonance or above resonance, where the derivation of appropriate phase durations becomes significantly more involved. This work presents a full analytical method to calculate optimal phase durations for the fixed-ratio FCML converter across all rational conversion ratios while operating at or above resonance. Hardware results for an N=5 FCML converter are presented for conversion ratios 5: 1, 5: 2, 5:3 and 5:4, illustrating the ability to use above-resonance operation to optimize the distribution of switching losses and conduction losses in the converter.

Individuals encounter problems daily wherein varying numbers of constraints require delimitation of memory to target goal-satisfying information. Multiply-constrained problems, such as the compound remote associates, are commonly used to study this type of problem solving. Since their development, multiply-constrained problems have been theoretically and empirically related to creative thinking, analytical problem solving, insight problem solving, and a multitude of other cognitive abilities. In the present study, we empirically evaluated the range of cognitive abilities previously associated with multiply-constrained problem solving to assess common versus unique predictive variance (i.e., working memory, attention control, episodic and semantic memory, and fluid and crystallized intelligence). Additionally, we sought to determine whether problem-solving ability and self-reported strategy adoption (analytical or insightful) were task specific or task general through the use of novel multiply-constrained problem-solving tasks (TriBond and Location Bond). Performance across these tasks was shown to be domain general, solutions derived through insightful strategies were more often correct than those derived through analytical strategies, and crystallized intelligence was the sole cognitive ability that provided unique predictive value after accounting for all other abilities.

Among mammals, the order Primates is exceptional in having a high taxonomic richness in which the taxa are arboreal, semiterrestrial, or terrestrial. Although habitual terrestriality is pervasive among the apes and African and Asian monkeys (catarrhines), it is largely absent among monkeys of the Americas (platyrrhines), as well as galagos, lemurs, and lorises (strepsirrhines), which are mostly arboreal. Numerous ecological drivers and species-specific factors are suggested to set the conditions for an evolutionary shift from arboreality to terrestriality, and current environmental conditions may provide analogous scenarios to those transitional periods. Therefore, we investigated predominantly arboreal, diurnal primate genera from the Americas and Madagascar that lack fully terrestrial taxa, to determine whether ecological drivers (habitat canopy cover, predation risk, maximum temperature, precipitation, primate species richness, human population density, and distance to roads) or species-specific traits (body mass, group size, and degree of frugivory) associate with increased terrestriality. We collated 150,961 observation hours across 2,227 months from 47 species at 20 sites in Madagascar and 48 sites in the Americas. Multiple factors were associated with ground use in these otherwise arboreal species, including increased temperature, a decrease in canopy cover, a dietary shift away from frugivory, and larger group size. These factors mostly explain intraspecific differences in terrestriality. As humanity modifies habitats and causes climate change, our results suggest that species already inhabiting hot, sparsely canopied sites, and exhibiting more generalized diets, are more likely to shift toward greater ground use.

This work presents a distributed regenerative snubber network with reduced part count in multi-level converter designs. The proposed technique utilizes the ordinarily detrimental parasitic commutation loop inductance to harvest COSS-related energy using a network of high-speed diode-capacitor catching circuits. The proposed approach has several attractive features: First, VDS overshoot is greatly reduced, as with conventional snubber design. Second, the speed of switching transitions may be increased substantially for reduced overlap loss. Third, layout design effort is relaxed, with larger commutation loop geometries expected to improve system performance. Fourth, a soft-charged daisy-chain allows multiple snubbers to sequentially transfer harvested energy to a common collection point with high efficiency. Finally, a single active component is used to resonate recovered energy back into the primary power path resulting in increased converter efficiency. A hardware prototype demonstrates intended operation in a 6-level flying capacitor multilevel (FCML) converter, with measured waveforms illustrating further improvement with modified active balancing control.

The flying capacitor multilevel (FCML) converter has shown promise for high step-up/down conversion ratio applications due to its relatively low switch stress and small inductor volume. For higher level-count $(N\geq 3)$ variations of this topology, there is limited research on resonant mode operation, despite its potential to yield considerable performance benefits for fixed conversion ratio applications. When operating resonantly, the decreased inductance requirement compared to regulated operation can further reduce the magnetic volume and improve transient response, while also allowing for zero-voltage/zero-current switching (ZCS/ZVS). This work presents and analyzes a clocking scheme required to operate an $N:\boldsymbol{1}$ FCML converter both at-resonance and above-resonance, while maintaining mini-mum current ripple for reduced losses. A complete derivation is presented, enabling the calculation of precise phase durations as a function of switching frequency. Moreover, a 5:1 FCML hardware prototype is demonstrated, verifying intended operation both at-and above-resonance, in addition to highlighting the achievable loss reduction with the proposed switching scheme.

With increasing calls of electrification for trans-portation (e.g, electric vehicles, hybrid or electric aircraft), the need for systematic guidelines that gauge passive component specific energy density for weight-optimized converter design has be-come apparent. Observing a lack of data sets and corresponding modeling process for passive components that usually dominate a converter's weight, this work proposes a transformation that estimates the specific energy density of passive components from comprehensively surveyed volumetric energy density data and empirical specific density models, and thus forms a convenient guideline for converter weight optimization. The proposed model is then applied to a converter designed for electric aircraft applications to showcase the component mass estimation and selection process along with estimation accuracy.

This study presents the perspectives and pedagogical practices of teachers who self-identify as social justice educators. Interviews with these social justice educators, who teach in large, diverse, metropolitan school districts, show that they create equitable spaces for their students. An analysis of the interview data concerning their beliefs and the ways that they describe their engagement with culturally and linguistically diverse learners showed that the practices of these social justice educators center students' perspectives, propose culturally sustaining choices, provide access to multicultural resources, and offer a space for counternarratives and revisionism in their classrooms.

Numerous national and state endeavors have advocated for approaches, funding, and programs focused on expanding the science, technology, engineering, and mathematics (STEM) workforce of the nation and investing in education to cultivate a more diverse and impactful cohort of students who pursue STEM pathways. Educators, support personnel, and policymakers are in a position to engage in discussions about expanding STEM college readiness (STEM-CR) and participation. However, few are cognizant that STEM-CR is a progression that students strive for in developing skills, behaviors, and attitudes that spans over time. The current study established and validated a measurement model of student STEM-CR in mathematics and science utilizing the High School Longitudinal Study of 2009. The model was created based on a multidimensional and theoretical perspective of college readiness using a confirmatory factor analysis and modeling approach that accounted for measurement invariance. The sample (N = 16,044) comes from a racialized/ethnoracial and socioeconomically diverse high school population in the United States. The findings confirmed that STEM-CR involves four related yet distinct dimensions of Think, Know, Act, and Go. Results also demonstrated soundness of these STEM-CR dimensions by race and gender (key learning skills and techniques/Act). Academic self-efficacy was the strongest dimension of our STEM-CR model and strongly predicted academic achievement and college enrollment. Research and practice implications are discussed.