Publications

Preparation and Characterization of High-Surface-Area Bi_{(1–<i>x</i>)/3}V_1–<i>x</i>Mo_<i>x</i>O₄Catalysts

We report the successful application of a templating approach employing ordered mesoporous carbon to the synthesis of BiVO4, Bi2Mo3O12, and Bi0.85V0.55Mo0.45O4 and the performance of these materials as catalysts for the oxidation of propene to acrolein. Ordered mesoporous carbon templates were used to control the nucleation and growth of the mixed metal oxide crystals, allowing higher final surface areas to be obtained. The resulting materials were characterized by X-ray diffraction, Raman spectroscopy, transmission electron microscopy, X-ray photoelectron spectroscopy, and BET surface area analysis. The surface area of the mixed metal oxide catalysts was found to depend on the type of mesoporous silica used to prepare the carbon template and on the conditions under which the carbon template was formed. Through an appropriate choice of template, the surface areas of the mixed metal oxides exceeded 15 m(2)/g. Catalytic testing revealed that materials produced via templating in ordered mesoporous carbon had per-gram activities that were up to 85 times higher than those produced by a conventional hydrothermal synthesis and exhibited stable catalytic activities over 24 h.

Textual Explanations for Self-Driving Vehicles

The Berkeley Automatic Imaging Telescope

We describe the design and control system of the Berkeley Automatic Imaging Telescope (BAIT), an observatory that performs all its tasks with minimal human intervention. We concentrate on the system's software, especially that which communicates with astronomers at remote sites and that which schedules targets during the night. BAIT has been in nearly continuous operation since January, 1992; we present an analysis of its performance during its first eight months.

ChemInform Abstract: PREPARATION, CHARACTERIZATION, AND PHOTOELECTRONIC PROPERTIES OF GERMANIUM‐SUBSTITUTED FERRIC OXIDE SINGLE CRYSTALS

Abstract Die Darstellung von Fe2‐"Ge"O3 (x ä 0.02)‐Einkristallen erfolgt durch chemischen Transport mit TeCl 4 als Transportreagens.

Attitudes of People with Disabilities toward Physician-Assisted Suicide Legislation: Broadening the Dialogue

This article presents the methods, findings, and implications of a participatory action research project that attempted to shed additional light on the debate over death with dignity (DWD) or physician-assisted suicide(PAS) legislation. In-depth, qualitative interviews with forty-five physically disabled residents of the San Francisco Bay Area, conducted by others with disabilities, revealed a wide breadth of opinions about and attitudes toward such legislation. For close to half of the participants, the desire for autonomy in making end-of-life decisions was a primary concern, yet fear that PAS legislation could violate this autonomy in various ways was a deep concern as well. Also reported were widespread accounts of disability-based discrimination and frequent expressions of fear about openly discussing positions that diverge from the official, publicly held opinions of disability leaders who oppose such legislation. The findings support those of a recent Harris poll demonstrating considerable diversity of opinion about PAS legislation among people with disabilities. The findings further suggest the need for additional research on the apparent disjunction between the diversity of attitudes held by those interviewed and the more unified position taken by many disability activists. Use of the study findings to promote greater dialogue within the community and to better position people with disabilities to take their place at the policy table also is discussed. In addition, the findings are seen as reinforcing the need for the public health community to become more engaged in this central ethical debate.

Surface Engineering of Polycrystalline Silicon Microelectromechanical Systems for Fatigue Resistance

No abstract is provided for this article.

Delay scheduling

As organizations start to use data-intensive cluster computing systems like Hadoop and Dryad for more applications, there is a growing need to share clusters between users. However, there is a conflict between fairness in scheduling and data locality (placing tasks on nodes that contain their input data). We illustrate this problem through our experience designing a fair scheduler for a 600-node Hadoop cluster at Facebook. To address the conflict between locality and fairness, we propose a simple algorithm called delay scheduling: when the job that should be scheduled next according to fairness cannot launch a local task, it waits for a small amount of time, letting other jobs launch tasks instead. We find that delay scheduling achieves nearly optimal data locality in a variety of workloads and can increase throughput by up to 2x while preserving fairness. In addition, the simplicity of delay scheduling makes it applicable under a wide variety of scheduling policies beyond fair sharing.

Stepwise separation of Co, Mn, Zn, and Cd from Co purification residue (CPR) in Zn hydrometallurgy

Variability Study for Low-Voltage Microelectromechanical Relay Operation

Body-biased microelectromechanical relays previously have been developed for ultralow-power digital logic applications and demonstrated to reliably switch ON/OFF with sub-50-mV gate voltage swing. Since variability in relay switching voltages can practically limit reduction in the operating voltage of a relay-based integrated circuit, the effects of process-induced variations and device operating conditions, as well as the stability of relay switching voltages, are investigated in this paper. Antistiction coating is shown to stably reduce hysteresis voltage and random variation thereof, which is beneficial for voltage scaling.

The photoionization mechanism of LINERs: stellar and nonstellar

CCDC 1864939: Experimental Crystal Structure Determination

An entry from the Cambridge Structural Database, the world’s repository for small molecule crystal structures. The entry contains experimental data from a crystal diffraction study. The deposited dataset for this entry is freely available from the CCDC and typically includes 3D coordinates, cell parameters, space group, experimental conditions and quality measures.

Synthetic spectra test data

Test dataset to evaluate ML/DL models for the classification of synthetic spectra

Oscillator Made of Only One Memristor and One Battery

Contrary to the traditional belief that at least two energy-storage elements (capacitor and/or inductor) and a locally-active nonlinearity are needed to build an electronic oscillator, this paper presents an oscillator made with only two circuit elements, namely, a memristor and a battery. This simplest of all physical oscillators also serves as a textbook example for explaining the intimate relationship between the super-critical Hopf bifurcation phenomenon and the edge of chaos.

Sleep and Inflammation During Adolescence

ABSTRACT Objective To investigate the associations between objective and subjective dimensions of adolescent sleep and C-reactive protein (CRP), a key biomarker of inflammation that predicts chronic health problems in adulthood, and whether the associations vary as a function of adolescents' age. Methods A total of 315 adolescents (14.5–18.4 years) wore wrist actigraphs at night to objectively estimate their sleep duration and variability across nights, and completed the Pittsburgh Sleep Quality Index to assess their subjective sleep quality. CRP levels were assayed from dried blood spots obtained from finger pricks. To control for adiposity, age- and sex-specific body mass index percentiles were obtained from height and weight measurements. Results Nightly variability in sleep duration was associated with higher levels of CRP ( b = 0.13, p = .045). Shorter average sleep duration was associated with higher CRP, but only among younger adolescents ( b = −0.11, p = .041). Subjective sleep quality was not associated with CRP. Conclusions The association of sleep with inflammation during adolescence seems more evident in objective dimensions of sleep duration and variability than in the subjective dimensions of sleep quality. Insufficient sleep may be particularly consequential for younger adolescents.

CCDC 2121207: Experimental Crystal Structure Determination

An entry from the Cambridge Structural Database, the world’s repository for small molecule crystal structures. The entry contains experimental data from a crystal diffraction study. The deposited dataset for this entry is freely available from the CCDC and typically includes 3D coordinates, cell parameters, space group, experimental conditions and quality measures.

Assessing Thermodynamic Selectivity of Solid-State Reactions for the Predictive Synthesis of Inorganic Materials

Synthesis is a major challenge in the discovery of new inorganic materials. Currently, there is limited theoretical guidance for identifying optimal solid-state synthesis procedures. We introduce two selectivity metrics, primary and secondary competition, to assess the favorability of target/impurity phase formation in solid-state reactions. We used these metrics to analyze 3,520 solid-state reactions in the literature, ranking existing approaches to popular target materials. Additionally, we implemented these metrics in a data-driven synthesis planning workflow and demonstrated its application in the synthesis of barium titanate (BaTiO$_3$). Using an 18-element chemical reaction network with first-principles thermodynamic data from the Materials Project, we identified 82,985 possible BaTiO$_3$ synthesis reactions and selected nine for experimental testing. Characterization of reaction pathways via synchrotron powder X-ray diffraction reveals that our selectivity metrics correlate with observed target/impurity formation. We discovered two efficient reactions using unconventional precursors (BaS/BaCl$_2$ and Na$_2$TiO$_3$) that produce BaTiO$_3$ faster and with fewer impurities than conventional methods, highlighting the importance of considering complex chemistries with additional elements during precursor selection. Our framework provides a foundation for predictive inorganic synthesis, facilitating the optimization of existing recipes and the discovery of new materials, including those not easily attainable with conventional precursors.

Crafting Interpretable Embeddings by Asking LLMs Questions

Large language models (LLMs) have rapidly improved text embeddings for a growing array of natural-language processing tasks. However, their opaqueness and proliferation into scientific domains such as neuroscience have created a growing need for interpretability. Here, we ask whether we can obtain interpretable embeddings through LLM prompting. We introduce question-answering embeddings (QA-Emb), embeddings where each feature represents an answer to a yes/no question asked to an LLM. Training QA-Emb reduces to selecting a set of underlying questions rather than learning model weights. We use QA-Emb to flexibly generate interpretable models for predicting fMRI voxel responses to language stimuli. QA-Emb significantly outperforms an established interpretable baseline, and does so while requiring very few questions. This paves the way towards building flexible feature spaces that can concretize and evaluate our understanding of semantic brain representations. We additionally find that QA-Emb can be effectively approximated with an efficient model, and we explore broader applications in simple NLP tasks.

Resistance Exercise and Oxandrolone for Men With HIV-Related Weight Loss—Reply