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Search for heavy Majorana neutrino in lepton number violating decays of
No full textUsing the data sample of an integrated luminosity of 2.93 fb taken at the center-of-mass energy of 3.773 GeV, we search for the Majorana neutrino in the lepton number violating decays . No significant signal is observed, and the upper limits on the branching fraction at the 90% confidence level are set to be , and . The Majorana neutrino is searched for with different mass assumptions ranging from 0.25 to 1.0 GeV/ in the decays and , and the upper limits on the branching fraction at the 90% confidence level are extracted to be at the level of , depending on the mass of Majorana neutrino. The constraints on the mixing matrix element are also evaluated
Search for rare decay
No full textUsing a data sample of events collected at = 3.686 GeV with the BESIII detector at the BEPCII, we search for the rare decay via . No signal events are observed and the upper limit on the branching fraction is set to be at the 90% confidence level, which is still about one order of magnitude higher than the Standard Model prediction
Study of the decay
No full textWe report a study of the decay based on a sample of 2.93 fb annihilation data collected at the center-of-mass energy of 3.773 GeV with the BESIII detector at the BEPCII collider. The total branching fraction is determined to be , which is the most precise to date. According to a detailed analysis of the involved dynamics, we find this decay is dominated with the contribution and present an improved measurement of its branching fraction to be . We further access their hadronic form-factor ratios for the first time as and . In addition, we observe a significant -wave component accounting for of the total decay rate
DNA duplex recognition activates Exo1 nuclease activity
No full textExonuclease 1 (Exo1) is an evolutionarily conserved eukaryotic nuclease that plays a multifaceted role in maintaining genome stability. The biochemical attributes of Exo1 have been extensively characterized via conventional assays. However, the key step governing its activation remains elusive. Extending the previous finding that Exo1 can digest a randomly selected single-stranded DNA (ssDNA) but not a poly(dT) oligonucleotide and using purified recombinant Exo1 and nuclease and electrophoretic mobility shift assays, here we determined that DNA hairpins with a stem size of 4 bp or longer are able to activate Exo1-mediated digestion of ssDNA. We further provide evidence suggesting that Exo1 uses an evolutionarily conserved residue, Lys¹⁸⁵. This residue interacted with the phosphate group bridging the third and fourth nucleotide on the digestion strand of the substrate DNA for duplex recognition, critical for Exo1 activation on not only ssDNA but also dsDNA. Additionally, the defect of an exo1-K185A mutant in duplex digestion was partially rescued by longer overhanging DNA. However, we noted that the enhanced Exo1 nuclease activity by longer overhanging DNA is largely eliminated by replication protein A (RPA), likely because of the previously reported RPA activity that strips Exo1 off the ssDNA. We conclude that duplex DNA contact by Exo1 is a general mechanism that controls its activation and that this mechanism is particularly important for digestion of duplex DNA whose nascent ssDNA is bound by RPA
Love, Lies, and Money: Financial Infidelity in Romantic Relationships
No full textRomantic relationships are built on trust, but partners are not always honest about their financial behavior—they may hide spending, debt, and savings from one another. This article introduces the construct of financial infidelity, defined as “engaging in any financial behavior expected to be disapproved of by one’s romantic partner and intentionally failing to disclose this behavior to them.” We develop and validate the Financial Infidelity Scale (FI-Scale) to measure individual variation in consumers' financial infidelity proneness. In 10 lab studies, one field study, and analyses of real bank account data collected in partnership with a couples’ money-management mobile application, we demonstrate that the FI-Scale has strong psychometric properties, is distinct from conceptually related scales, and predicts actual financial infidelity among married consumers. Importantly, the FI-Scale predicts a broad range of consumption-related behaviors (e.g., spending despite anticipated spousal disapproval, preferences for discreet payment methods and unmarked packaging, concealing bank account information). Our work is the first to introduce, define, and measure financial infidelity reliably and succinctly and examine its antecedents and consequences
Direct Observation and Analysis of the Halo-Amino-Nitro Alkane Functional Group
No full textConventional amide synthesis is a mainstay in discipline-spanning applications, and it is a reaction type that historically developed as a singular paradigm when considering the carbon-nitrogen bond-forming step. Umpolung amide synthesis (UmAS) exploits the unique properties of an a-halo nitroalkane in its reaction with an amine to produce an amide. The ‘‘umpolung’’ moniker reflects its para- digm-breaking C–N bond formation on the basis of evidence that the nucleo- philic nitronate carbon and electrophilic nitrogen engage to form a tetrahedral intermediate (TI) that is an unprecedented functional group, a 1,1,1-halo-amino- nitro alkane (HANA). Studies probing HANA transience have failed to capture this (presumably) highly reactive intermediate. We report here the direct obser- vation of a HANA, its conversion thermally to an amide functionality, and quan- titative analysis of this process using computational techniques. These findings validate the HANA as a functional group common to UmAS and diverted UmAS, opening the door to its targeted use and creative manipulation
Thermally and Magnetically Robust Triplet Ground State Diradical
No full textHigh spin (S = 1) organic diradicals may offer enhanced properties with respect to several emerging technologies, but typically exhibit low singlet triplet energy gaps and possess limited thermal stability. We report triplet ground state diradical 2 with a large singlet-triplet energy gap, ΔEST ≥ 1.7 kcal mol−1, leading to nearly exclusive population of triplet ground state at room temperature, and good thermal stability with onset of decomposition at ~160 °C under inert atmosphere. Magnetic properties of 2 and the previously prepared diradical 1 are characterized by SQUID magnetometry of polycrystalline powders, in polystyrene glass, and in other matrices. Polycrystalline diradical 2 forms a novel one-dimensional (1D) spin-1 (S = 1) chain of organic radicals with intrachain antiferromagnetic coupling of J′/k = −14 K, which is associated with the N···N and N···O intermolecular contacts. The intrachain antiferromagnetic coupling in 2 is by far strongest among all studied 1D S = 1 chains of organic radicals, which also makes 1D S = 1 chains of 2 most isotropic, and therefore an excellent system for studies of low-dimensional magnetism. In polystyrene glass and in frozen benzene or dibutyl phthalate solution, both 1 and 2 are monomeric. Diradical 2 is thermally robust and is evaporated under ultra-high vacuum to form thin films of intact diradicals on silicon substrate, as demonstrated by X-ray photoelectron spectroscopy. Based on C-K NEXAFS spectra and AFM images of the ~1.5-nm thick films, the diradical molecules form islands on the substrate with molecules stacked approximately along the crystallographic a-axis. The films are stable under ultra-high vacuum for at least 60 h but show signs of decomposition when exposed to ambient conditions for 7 h
Verbal Learning and Memory in Early-Implanted, Prelingually Deaf Adolescent and Adult Cochlear Implant Users
No full textPurpose: The purpose of this study was to investigate the information-processing strategies of early-implanted, prelingually deaf cochlear implant (CI) users with the California Verbal Learning Test–Second Edition (CVLT-II; Delis, Kramer, Kaplan, & Ober, 2000), a well-established normed measure of verbal learning and memory used in neuropsychological assessments of memory loss. Method: Verbal learning and memory skills were compared in 20 older adolescent and young adult prelingually deaf long-term early-implanted CI users and their 24 normal hearing (NH) peers using the CVLT-II, a widely used multitrial free recall test of verbal learning and memory. Results: On average, CI users recalled fewer words than their NH peers across the immediate, delayed, and cued recall trials of the CVLT-II but were comparable to their NH peers on yes/no recognition memory. CI users showed little evidence of semantic clustering of words during free recall but greater serial clustering compared to their NH peers, suggesting fundamental disturbances in automatic semantic activation of words from long-term memory. No differences were found in verbal memory between CI users and their NH peers on measures of retroactive interference and encoding/retrieval interactions. Performance on the 2nd word list of the CVLT-II (List B) and amount of semantic clustering of words during recall were correlated with sentence recognition in the CI group. Conclusion: Study findings demonstrate significant differences in free recall performance and information-processing strategies that early-implanted, prelingually deaf CI users use to encode, organize, store, and retrieve spoken words in conventional verbal list learning paradigms, compared to their NH peers. Because verbal learning and memory are core foundational processes routinely used in daily functioning for a wide range of neurocognitive and language processing operations, these findings suggest potential domains for assessment and novel interventions to promote the development of optimal outcomes in prelingually deaf early-implanted longterm CI users
Error-Correcting Decoders for Communities in Networks
No full textAs recent work demonstrated, the task of identifying communities in networks can be considered analogous to the classical problem of decoding messages transmitted along a noisy channel. We leverage this analogy to develop a community detection method directly inspired by a standard and widely-used decoding technique. We further simplify the algorithm to reduce the time complexity from quadratic to linear. We test the performance of the original and reduced versions of the algorithm on artificial benchmarks with pre-imposed community structure, and on real networks with annotated community structure. Results of our systematic analysis indicate that the proposed techniques are able to provide satisfactory results