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Observation of at center-of-mass energies above 3.7 GeV
No full textThe state is observed in the process at center-of-mass energies between 3.7 and 4.6∼GeV with a statistical significance larger than 10 using data collected with the BESIII detector operating at the BEPCII storage ring. This is the first observation of the in this process. The mass and width of the are determined to be (2135±8±9) MeV/ and (104±24±12) MeV, respectively, and the production cross section of is at a several hundred femtobarn level. No significant signal for the process is observed and the upper limit on is estimated to be 0.43 at the 90% confidence level. We also search for . No significant signal is observed, indicating a strong suppression relative to the corresponding decay, in violation of the "12% rule.
Observation of and
No full textSeveral intermediate states of the reaction channels and are studied using the data samples collected with the BESIII detector at center-of-mass energies above 4.08 GeV. For the first time in this final state, a signal is seen in the invariant mass spectrum, with a statistical significance of 5.2 at =4.42 GeV. There is also evidence for this resonance at = 4.26 and 4.36 GeV with statistical significance of 3.2 and 3.3, respectively. In addition, the Born cross section of is measured. The proposed heavy-quark-spin-symmetry partner of the , the state , is also searched for in the invariant mass spectra. No obvious signal is found. The upper limit of the Born cross section of the process combined with the branching fraction is measured. Also, the processes are investigated. The neutral mode with is reported with statistical significance of 7.4 at = 4.42 GeV for the first time, and evidence with statistical significance of 3.2 and 3.3 at = 4.36 and 4.60 GeV is seen, respectively. No evident signal for the process is reported. Evidence for is reported with statistical significance of 3.1 and 3.0 at = 4.36 and 4.42 GeV, respectively
Search for Baryon and Lepton Number Violation in
No full textUsing events collected by the BESIII detector at the Beijing Electron Positron Collider, we search for the process for the first time. In this process, both baryon and lepton number conservation is violated. No signal is found and the upper limit on the branching fraction is set to be at the 90% Confidence Level
Search for the decay
No full textUsing a data sample of events collected with the BESIII detector, a search for via is performed for the first time. No significant signal is observed in the invariant mass spectrum, and the branching fraction of is determined to be less than 1.33 × 10 at the 90% confidence level
BONGA'S TRANSATLANTIC ROUTES
No full textThis work is a study of the album Angola 74 de Bonga to analyze the relations about Bomga and his music. Bonga observed the daily life in Kipiri, where he was born, and the day-to-day experience in Luanda's musseques and the impact of music in the region. Its “roots” and its source (Pereira, 2018; Eduardo, 2012). But the song “Ghinawa” from Angola 74, in sounds and history, suggests routes and not roots. Listening carefully, I trace a transatlantic urban trajectory for Bonga's work
Self-regulated studying behavior, and the social norms that influence it
No full textTeachers commonly use injunctive norms when telling students what they should be doing. But researchers find that sometimes descriptive norms, information about what others are actually doing, are more powerful influencers of behavior. In the present work, we examine which norm is more effective at increasing self‐regulated studying and performance in an online college course across two semesters. To do this, we randomly assigned 751 undergraduate Introductory Psychology students to receive email messages at the start of every content unit that either contained descriptive norms, injunctive norms, information about the course, or a no message control. We found that injunctive norms increased study behaviors aimed at fulfilling course requirements (completion of assigned activities), but did not improve learning outcomes. Descriptive norms increased behaviors aimed at improving knowledge (ungraded practice with activities after they were due), and improved performance. These results suggest that norms more effectively influence behavior when there is a match, or a sense of fit, between the goal of the behavior (fulfilling course requirements vs. learning) and the pull of a stated norm (social approval vs. efficacy). We discuss these implications with respect to students' motivations for self‐regulated studying behavior in contemporary learning environments, and the overall goals of education
Transverse lipid organization dictates bending fluctuations in model plasma membranes
No full textMembrane undulations play a vital role in many biological processes, including the regulation of membrane protein activity. The asymmetric lipid composition of most biological membranes complicates theoretical description of these bending fluctuations, yet experimental data that would inform any such a theory is scarce. Here, we used neutron spin-echo (NSE) spectroscopy to measure the bending fluctuations of large unilamellar vesicles (LUV) having an asymmetric transbilayer distribution of high- and low-melting lipids. The asymmetric vesicles were prepared using cyclodextrin-mediated lipid exchange, and were composed of an outer leaflet enriched in egg sphingomyelin (ESM) and an inner leaflet enriched in 1-palmitoyl-2-oleoyl-phosphoethanolamine (POPE), which have main transition temperatures of 37 °C and 25 °C, respectively. The overall membrane bending rigidity was measured at three temperatures: 15 °C, where both lipids are in a gel state; 45 °C, where both lipids are in a fluid state; and 30 °C, where there is gel-fluid co-existence. Remarkably, the dynamics for the fluid asymmetric LUVs (aLUVs) at 30 °C and 45 °C do not follow trends predicted by their symmetric counterparts. At 30 °C, compositional asymmetry suppressed the bending fluctuations, with the asymmetric bilayer exhibiting a larger bending modulus than that of symmetric bilayers corresponding to either the outer or inner leaflet. We conclude that the compositional asymmetry and leaflet coupling influence the internal dissipation within the bilayer and result in membrane properties that cannot be directly predicted from corresponding symmetric bilayers
Certified quantum measurement of Majorana fermions
No full textWe present a quantum self-testing protocol to certify measurements of fermion parity involving Majorana fermion modes. We show that observing a set of ideal measurement statistics implies anticommutativity of the implemented Majorana fermion parity operators, a necessary prerequisite for Majorana detection. Our protocol is robust to experimental errors. We obtain lower bounds on the fidelities of the state and measurement operators that are linear in the errors. We propose to analyze experimental outcomes in terms of a contextuality witness W , which satisfies ⟨ W ⟩ ≤ 3 for any classical probabilistic model of the data. A violation of the inequality witnesses quantum contextuality, and the closeness to the maximum ideal value ⟨ W ⟩ = 5 indicates the degree of confidence in the detection of Majorana fermions
Human monoclonal antibodies against chikungunya virus target multiple distinct epitopes in the E1 and E2 glycoproteins
No full textChikungunya virus (CHIKV) is a mosquito-transmitted alphavirus that causes persistent arthritis in a subset of human patients. We report the isolation and functional characterization of monoclonal antibodies (mAbs) from two patients infected with CHIKV in the Dominican Republic. Single B cell sorting yielded a panel of 46 human mAbs of diverse germline lineages that targeted epitopes within the E1 or E2 glycoproteins. MAbs that recognized either E1 or E2 proteins exhibited neutralizing activity. Viral escape mutations localized the binding epitopes for two E1 mAbs to sites within domain I or the linker between domains I and III; and for two E2 mAbs between the β-connector region and the B-domain. Two of the E2-specific mAbs conferred protection in vivo in a stringent lethal challenge mouse model of CHIKV infection, whereas the E1 mAbs did not. These results provide insight into human antibody response to CHIKV and identify candidate mAbs for therapeutic intervention
Patterns and Frequency of Current e-Cigarette Use in United States Adults
No full textBackground: In the United States (US), electronic cigarette (e-cigarette) use prevalence has increased since 2010. Few studies, however, have addressed frequency of use at the population-level. This study examines patterns and correlates of e-cigarette use frequency in a novel national sample. Methods: Data were from 36,277 US adults interviewed between 2012 and 2013 for the National Epidemiologic Survey on Alcohol and Related Conditions-III (NESARC-III). Sociodemographic characteristics, other tobacco/drug use, and psychiatric disorders were compared by e-cigarette use status (i.e. current [past-month], past, never) and e-cigarette use frequency (i.e. infrequent [≤3 days/month], moderate [1–6 days/week], daily). Multinomial logistic regression models compared correlates of e-cigarette use status and e-cigarette use frequency. Results: Current e-cigarette use was low in adults (1.4%) and past e-cigarette use was 3.9%. Among current e-cigarette users, 38.1% were infrequent users, 32.9% were moderate users, and 29.0% were daily users. Compared to infrequent e-cigarette users, daily users were more likely to be male and older, but less likely to be current cigarette smokers and alcohol drinkers (p’s < .05). Compared to daily e-cigarette users, moderate users were more likely be female, current cigarette smokers, and fall into the 25–34 age group (p’s < .05). Moderate and daily e-cigarette users had higher prevalence of current extra-medical opioid use than infrequent users (p’s < .05). Conclusions/Importance: E-cigarette users were most often infrequent users versus moderate or daily users. Compared to infrequent and moderate users, daily e-cigarette users were less likely to be current alcohol drinkers or cigarette smokers. Novel findings highlight a correlation between more frequent e-cigarette and opioid use