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  1. We present a novel method that automatically measures quality of sentential paraphrasing. Our method balances two conflicting criteria: semantic similarity and lexical diversity. Using a diverse annotated corpus, we built learning to rank models on edit distance, BLEU, ROUGE, and cosine similarity features. Extrinsic evaluation on STS Benchmark and ParaBank Evaluation datasets resulted in a model ensemble with moderate to high quality. We applied our method on both small benchmarking and large-scale datasets as resources for the community.
    Free, publicly-accessible full text available August 7, 2022
  2. The transcriptional coactivator YAP1 (yes-associated protein 1) is a critical nuclear effector of the Hippo pathway. The serine/threonine protein kinases STK3/4 and LATS1/2, core components of the Hippo pathway, phosphorylate and inhibit YAP1 nuclear localization. Previously, we reported that the interaction of nuclear YAP1 with androgen receptor (AR) might play a critical role in prostate cancer progression and therapeutic relapse (Kuser-Abali et al., Nat. Commun. 2015). Here, we investigated the regulation of YAP1 by androgens in isogenic, androgen-responsive LNCaP and androgen non-responsive C4-2 prostate cancer cell models. We demonstrated that androgen suppressed the inhibitory phospho-Ser127 site on YAP1 in LNCaPmore »cells, but the effects of androgen on phospho-Ser127 was modest in C4-2 cells. In agreement with this observation, androgen increased the presence of nuclear YAP1 in LNCaP cells, whereas regardless of androgen exposure the YAP1 protein was primarily expressed in C4-2 cell nuclei. We also demonstrated that androgen exposure suppressed the levels of phospho-Ser127 induced by okadaic acid, which is a potent inhibitor of the Ser/Thr phosphatases PP1 and PP2A. Moreover, the pharmacological inhibition of androgen receptor (AR) signaling by enzalutamide reversed the inhibitory effects of androgen on phospho-Ser127, which coincided with the inhibition of YAP1 nuclear localization. Similarly, the genetic inhibition of AR signaling by small interfering RNA (siRNA) reduced phospho-Ser127 levels. Additionally, the silencing of the STK3/4 and LATS1/2 signaling by siRNA resulted in increases in YAP1 protein levels. Furthermore, our analysis of the TCGA (The Cancer Genome Atlas) prostate adenocarcinoma data set indicates that the levels of YAP1 and AR mRNA expression were positively correlated in prostate cancer clinical samples. These observations suggest that AR signaling promotes YAP1 nuclear localization by suppressing phospho-Ser127, possibly through the protein phosphatases PP1 and PP2A, and supporting a new mechanism of YAP1 regulation and YAP1-mediated cancer cell growth and survival.« less
  3. The nature and extent of the spin-entanglement in the triplet-triplet biexciton with total spin zero in correlated-electron π-conjugated systems continues to be an enigma. Differences in the ultrafast transient absorption spectra of free triplets versus the triplet-triplet can give a measure of the entanglement. This, however, requires theoretical understandings of transient absorptions from the optical spin-singlet, the lowest spin-triplet exciton, as well as from the triplet-triplet state, whose spectra are often overlapping and hence difficult to distinguish. We present a many-electron theory of the electronic structure of the triplet-triplet, and of complete wavelength-dependent excited state absorptions (ESAs) from all threemore »states in a heteroacene dimer of interest in the field of intramolecular singlet fission. The theory allows direct comparisons of ESAs with existing experiments as well as experimental predictions, and gives physical understandings of transient absorptions within a pictorial exciton basis that can be carried over to other experimental systems.« less
  4. Free, publicly-accessible full text available May 1, 2023
  5. Free, publicly-accessible full text available April 1, 2023
  6. Abstract We search for gravitational-wave signals associated with gamma-ray bursts (GRBs) detected by the Fermi and Swift satellites during the second half of the third observing run of Advanced LIGO and Advanced Virgo (2019 November 1 15:00 UTC–2020 March 27 17:00 UTC). We conduct two independent searches: a generic gravitational-wave transients search to analyze 86 GRBs and an analysis to target binary mergers with at least one neutron star as short GRB progenitors for 17 events. We find no significant evidence for gravitational-wave signals associated with any of these GRBs. A weighted binomial test of the combined results finds nomore »evidence for subthreshold gravitational-wave signals associated with this GRB ensemble either. We use several source types and signal morphologies during the searches, resulting in lower bounds on the estimated distance to each GRB. Finally, we constrain the population of low-luminosity short GRBs using results from the first to the third observing runs of Advanced LIGO and Advanced Virgo. The resulting population is in accordance with the local binary neutron star merger rate.« less
    Free, publicly-accessible full text available April 1, 2023
  7. Free, publicly-accessible full text available March 1, 2023
  8. Intermediate-mass black holes (IMBHs) span the approximate mass range 100−10 5   M ⊙ , between black holes (BHs) that formed by stellar collapse and the supermassive BHs at the centers of galaxies. Mergers of IMBH binaries are the most energetic gravitational-wave sources accessible by the terrestrial detector network. Searches of the first two observing runs of Advanced LIGO and Advanced Virgo did not yield any significant IMBH binary signals. In the third observing run (O3), the increased network sensitivity enabled the detection of GW190521, a signal consistent with a binary merger of mass ∼150  M ⊙ providing direct evidencemore »of IMBH formation. Here, we report on a dedicated search of O3 data for further IMBH binary mergers, combining both modeled (matched filter) and model-independent search methods. We find some marginal candidates, but none are sufficiently significant to indicate detection of further IMBH mergers. We quantify the sensitivity of the individual search methods and of the combined search using a suite of IMBH binary signals obtained via numerical relativity, including the effects of spins misaligned with the binary orbital axis, and present the resulting upper limits on astrophysical merger rates. Our most stringent limit is for equal mass and aligned spin BH binary of total mass 200  M ⊙ and effective aligned spin 0.8 at 0.056 Gpc −3 yr −1 (90% confidence), a factor of 3.5 more constraining than previous LIGO-Virgo limits. We also update the estimated rate of mergers similar to GW190521 to 0.08 Gpc −3 yr −1 .« less
    Free, publicly-accessible full text available March 1, 2023
  9. Free, publicly-accessible full text available January 1, 2023