We report measurements of the branching fractions and CP asymmetries for B(±)→ηh(±) (h=K or π) and the observation of the decay B(0)→ηK(0) from the final data sample of 772×10(6) B ̅B pairs collected ...with the Belle detector at the KEKB asymmetric-energy e(+)e(-) collider. The measured branching fractions are B(B(±)→ηK(±))=(2.12±0.23±0.11)×10(-6), B(B(±)→ηπ(±))=(4.07±0.26±0.21)×10(-6), and B(B(0)→ηK(0))=(1.27(-0.29)(+0.33)±0.08)×10(-6), where the last decay is observed for the first time with a significance of 5.4 standard deviations (σ). We also find evidence for CP violation in the charged B modes, A(CP)(B(±)→ηK(±))=-0.38±0.11±0.01 and A(CP)(B(±)→ηπ(±))=-0.19±0.06±0.01 with significances of 3.8 σ and 3.0 σ, respectively. For all measurements, the first and second uncertainties are statistical and systematic, respectively.
This article is the second part of our review of the important role that symmetry plays in atomic and subatomic physics. We will concentrate on the discrete symmetries — parity, charge conjugation, ...and time reversal — that have played a significant part in the development of the ‘standard model’ of particle physics during the latter part of the 20th century. The importance of experimental tests of these symmetries, in both atomic and particle physics, and their sensitivity to new phenomena is also discussed. To conclude, we describe how ‘symmetry breaking’ in the standard model leads to the generation of mass via the Higgs mechanism and how the search for evidence of this symmetry violation is one of the principal goals of the Large Hadron Collider, which began operating at CERN, Switzerland in 2009.
A
bstract
We report the first measurement of the exclusive cross sections
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, and
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in the energy range from 10
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63 GeV to 11
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02 GeV. The
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...mesons are fully reconstructed in a large number of hadronic final states and the three channels are identified using a beam-constrained-mass variable. The shapes of the exclusive cross sections show oscillatory behavior with several maxima and minima. The results are obtained using data collected by the Belle experiment at the KEKB asymmetric-energy
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collider.
Abstract only Introduction: In the early months of COVID-19 pandemic, a decline in stroke hospital admissions were reported nationwide. In a large, diverse region of Southern California, a ...collaborative effort was made to collect real-time data trends in stroke code activations and to assess this impact locally. The San Diego (SD) County Stroke Receiving Centers demonstrated a notable decrease of 30% in stroke code activations from March-May 2020 as compared to the same timeframe in 2019, which motivated the group to dedicate time and resources to pursue a united community messaging focused on seeking emergency treatment for stroke. Methods: A unified marketing campaign was created in collaboration with SD County EMS and the SD region American Heart Association/American Stroke Association. A single graphic message was utilized that emphasized the importance of seeking emergency treatment when suffering signs of stroke, along with the slogan “We are here for you. Every minute matters.” Impact of the campaign was gauged by quantifying the number of times our message was viewed on social media and number of stroke code activations after the campaign ended. Results: The unified social media campaign was posted by 14 of the 18 SD County stroke receiving hospitals during the month of June 2020. The team utilized Facebook, Twitter, Instagram and LinkedIn to convey the message. The campaign yielded a total of 26,727 views. The median monthly stroke code activations in July 2020 increased to 34, as compared to 26.5 for March-May 2020. Conclusion: In a time when social distancing has become the norm, it is more important than ever to band together as a community. This endeavor demonstrates that virtual messaging serves as a viable option for community education during the COVID-19 pandemic and in the future. A unified social messaging campaign targeting the importance of seeking emergency care for stroke during the COVID-19 pandemic is an effective way to reach large numbers of people regionally.
Abstract only Introduction: On March 16, 2020 San Diego County implemented a stay at home order in response to COVID-19 pandemic; followed by the state of California instituting a shelter in place ...order. Locally, San Diego County’s stroke receiving centers (SRC) determined a 30% drop in stroke code activations between March-April 2020 compared to the same time in 2019 indicating a possible delay in seeking care. Utilizing discharge data, we sought to understand the impact of the stay at home order on the timeliness of seeking care. Hypothesis: We hypothesized an increase in last known normal (LKN) to hospital arrival time and a decrease in alteplase (tPA) and endovascular therapy (EVT) treatment rates between March 16-June 30 2020 compared to March 16-June 30 2019. Methods: AIS patients presenting to one of 16 SRC in San Diego County between March 16-June 30 in 2019 and 2020, discharged from the hospital or treated in the ED and transferred to another facility were included. Patients arriving as transfers from another facility were excluded. Results: In 2019, of 1,342 AIS cases LKN time was recorded for 85.6% of cases; of 1,092 cases in 2020 86.4% of cases had a LKN. Average LKN to arrival was 20.5 hours in 2019 and 32.4 hours in 2020 (p = .001, 95% CI 4.79, 18.93). In 2019, 209 (15.6%) received tPA and 91 (6.8%) had EVT. In 2020, 144 (13.2%) received tPA and 75 (6.9%) had EVT. Odds that a case in 2019 received tPA was 1.21 times that of cases in 2020 (p=.09). Odds that a case in 2019 had EVT was .99 times that of cases in 2020 (p=.93). Conclusion: Ischemic stroke patients arriving between March 16-June 30, 2020 had a longer LKN to arrival time compared to the same time frame in 2019. The longer time to arrival may have been due to patients waiting longer to seek care, as anecdotal information from patients eluded to. The odds of receiving tPA or EVT treatment in 2020 compared to 2019 were not statistically significant. This may be due to patients experiencing acute symptoms accessing healthcare at the same rate in 2020 as 2019. Analysis of percent of patients arriving within 4 hours of LKN and average NIHSS are important next steps to determine this. Regardless, during a time of community crisis, it is important to broadcast community messaging focusing on the importance of seeking emergency care for stroke-like symptoms.
Abstract only Introduction: In the early months of the COVID-19 pandemic, decreased numbers of stroke code activations were reported nationwide. In San Diego County, a diverse region that borders ...Mexico with over 4500 square miles and population 3.3 million, trends in COVID-19 cases varied geographically. We saw an overall decrease in stroke cases across our systems and aimed to better understand if high COVID infection rates in subregions affected stroke code activations. Methods: Stroke code activation data from 15 Stroke Receiving Centers were matched with COVID-19 case rates by patient home zip code. Patients arriving via emergency medical services (EMS) or private transportation were included. Patients with home zip codes outside of San Diego County were excluded. Data represented the cumulative rate of stroke codes and COVID-19 cases per 100,000 population per zip code for the period of March 1 through June 30, 2020. Results: We counted 1,927 stroke code activations across 106 zip codes in San Diego County. The average stroke code activation rate was 58.4 per 100,000 (range: 0-310.6) The median stroke code activation rate was 55.95 (IQR=32.1-73.1) per 100,000 population. The median COVID rate per zip code was 244.9 (IQR=177-448.4) per 100,000 population. There were 958 (49.7%) non-stroke diagnoses, 576 (29.9%) AIS, 272 (14.1%) TIA, 104 (5.4%) ICH and 17 (.9%) SAH. We did not identify a correlation between stroke code activation rates and COVID rates across zip codes (r=.17, p=.09, 95% CI(-.02, .35)). Conclusions: Across a large and diverse single-county region, no correlation was found between COVID positivity rate per zip code and stroke code activations. We found no decreases in stroke code activations in areas with high COVID rates.
Abstract On the Monterey Peninsula, many native stands of Monterey pine are overmature, largely as a result of fire suppression. In addition, the pathogen that causes pitch canker has recently been ...introduced and is now well established. Management practices aimed at increasing natural regeneration will convert these forests to younger age classes in which ecological and evolutionary processes are optimized within the constraints imposed by fire suppression, pitch canker, and occupation of the forest by humans.
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