Publications

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We propose Wolf, a WOrLd summarization Framework for accurate video captioning. Wolf is an automated captioning framework that adopts a mixture-of-experts approach, leveraging complementary strengths of Vision Language Models (VLMs). By utilizing both image and video models, our framework captures different levels of information and summarizes them efficiently. Our approach can be applied to enhance video understanding, auto-labeling, and captioning. To evaluate caption quality, we introduce CapScore, an LLM-based metric to assess the similarity and quality of generated captions compared to the ground truth captions. We further build four human-annotated datasets in three domains: autonomous driving, general scenes, and robotics, to facilitate comprehensive comparisons. We show that Wolf achieves superior captioning performance compared to state-of-the-art approaches from the research community (VILA1.5, CogAgent) and commercial solutions (Gemini-Pro-1.5, GPT-4V). For instance, in comparison with GPT-4V, Wolf improves CapScore both quality-wise by 55.6% and similarity-wise by 77.4% on challenging driving videos. Finally, we establish a benchmark for video captioning and introduce a leaderboard, aiming to accelerate advancements in video understanding, captioning, and data alignment. Webpage: https://wolfv0.github.io/.

We report a series of hydroarylations of unactivated olefins with trifluoromethyl-substituted arenes that occur with high selectivity for the linear product without directing groups on the arene. We also show that hydroarylations occur with internal, acyclic olefins to yield linear alkylarene products. Experimental mechanistic data provide evidence for reversible formation of an alkylnickel-aryl intermediate and rate-determining reductive elimination to form the carbon-carbon bond. Labeling studies show that formation of terminal alkylarenes from internal alkenes occurs by initial establishment of an equilibrating mixture of alkene isomers, followed by addition of the arene to the terminal alkene. Computational (DFT) studies imply that the aryl C-H bond transfers to a coordinated alkene without oxidative addition and support the conclusion from experiment that reductive elimination is rate-determining and forms the anti-Markovnikov product. The reactions are inverse order in α-olefin; thus the catalytic reaction occurs, in part, because isomerization creates a low concentration of the reactant α-olefin.

Abstract In the presence of Selectfluor as oxidant and only 3 mol% of a bimetallic gold bromide terminal alkenesulfonamides undergo the title reaction with arylboronic acids in most cases at room temperature to give five‐ and six‐membered N‐heterocycles.

Earth and Space Science Open Archive posterOpen AccessYou are viewing the latest version by default [v1]Evaluating a UAV-based mobile sensing system designed to quantify ecosystem-based methaneAuthorsDerekHollenbeckiDKristenManiesiDYangQuanCheniDDennisBaldocchiEugenieEuskircheniDLanceChristensenSee all authors Derek HollenbeckiDCorresponding Author• Submitting AuthorUniversity of California MercediDhttps://orcid.org/0000-0002-4782-1370view email addressThe email was not providedcopy email addressKristen ManiesiDGeology, Minerals, Energy, and Geophysics Science CenteriDhttps://orcid.org/0000-0003-4941-9657view email addressThe email was not providedcopy email addressYangQuan CheniDUniversity of California MercediDhttps://orcid.org/0000-0002-7422-5988view email addressThe email was not providedcopy email addressDennis BaldocchiUniversity of California Berkeleyview email addressThe email was not providedcopy email addressEugenie EuskircheniDUniversity of Alaska FairbanksiDhttps://orcid.org/0000-0002-0848-4295view email addressThe email was not providedcopy email addressLance ChristensenNASA Jet Propulsion Laboratoryview email addressThe email was not providedcopy email address

Cycle 1 JWST observations of Cepheids in SN Ia hosts resolved their red-giant-dominated NIR backgrounds, sharply reducing crowding and showing that photometric bias in lower-resolution HST data does not account for the Hubble tension. We present Cycle 2 JWST observations of >100 Cepheids in NGC 3447, a unique system that pushes this test to the limit by transitioning from low to no background contamination. NGC 3447, an SN Ia host at D~25 Mpc, is an interacting pair comprising (i) a spiral with mixed stellar populations, typical of H0 calibrators, and (ii) a young, star-forming companion (NGC 3447A) devoid of old stars and hence stellar crowdinga rare "perfect host" for testing photometric bias. We detect ~60 long-period Cepheids in each, enabling a "three-way comparison" across HST, JWST, and background-free conditions. We find no component-to-component offset (sigma<0.03 mag; a calibration independent test), and a 50% reduction in scatter to ~0.12 mag in the background-free case, the tightest seen for any SN Ia host. Across Cycles 1-2 we also measure Cepheids in all SH0ES hosts observed by JWST (19 hosts of 24 SNe Ia; >50% of the sample) and find no evidence of bias relative to HST photometry, including for the most crowded, distant hosts. These observations constitute the most rigorous test yet of Cepheid distances and provide strong evidence for their reliability. Combining JWST Cepheid measurements in 19 hosts (24 SNe Ia) with HST data (37 hosts, 42 SNe Ia) yields H0 = 73.49 +/- 0.93 km/s/Mpc. Including 35 TRGB-based calibrations (from HST and JWST) totals 55 SNe Ia and gives H0 = 73.18 +/- 0.88 km/s/Mpc, ~6 sigma above the LambdaCDM+CMB expectation.

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