38,083 research outputs found
First observation of and search for exotic baryons in systems
No full textThe process γγ→pp¯K+K- and its intermediate processes are measured for the first time using a 980 fb-1 data sample collected with the Belle detector at the KEKB asymmetric-energy e+e- collider. The production of pp¯K+K- and a Λ(1520)0 (Λ¯(1520)0) signal in the pK- (p¯K+) invariant mass spectrum are clearly observed. However, no evidence for an exotic baryon near 1540 MeV/c2, denoted as Θ(1540)0 (Θ¯(1540)0) or Θ(1540)++ (Θ(1540)--), is seen in the pK- (p¯K+) or pK+ (p¯K-) invariant mass spectra. Cross sections for γγ→pp¯K+K-, Λ(1520)0p¯K++c.c. and the products σ(γγ→Θ(1540)0p¯K++c.c.)B(Θ(1540)0→pK-) and σ(γγ→Θ(1540)++p¯K-+c.c.)B(Θ(1540)++→pK+) are measured. We also determine upper limits on the products of the χc0 and χc2 two-photon decay widths and their branching fractions to pp¯K+K- at the 90% credibility level
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Unpacking the role of political will in digital business ecosystem development for socioeconomic benefits
No full textAs digital technology transforms many organisational alliances, new collaborative networks such as digital business ecosystems have emerged. In digital business ecosystems, participants leverage technological innovations to develop capabilities for value co-creation. Despite the growing number of studies, there is lack of research on how political-will facilitates development of digital business ecosystems. Therefore, this study develops a framework to explicate the role of political-will in the development of digital business ecosystems to achieve socioeconomic benefits. The findings show that political-will leads to provision of resources and legislative support as well as formulation of strategic initiatives required at the birth, expansion and maturity phases of digital business ecosystems to generate socioeconomic benefits such as (1) reduced corruption, (2) improved operational processes, (3) increased government revenue, (4) reduced bureaucracy and (5) improved transparency, fairness and accountability
Observation of and
No full textInternational audienceWe report the study of B+→pΛ¯K+K- and B+→p¯ΛK+K+ decays using a 772×106 BB¯ pair data sample recorded on the ϒ(4S) resonance with the Belle detector at KEKB. The following branching fractions are measured: B(B+→pΛ¯K+K-)=(4.10-0.43+0.45±0.50)×10-6, B(B+→p¯ΛK+K+)=(3.70-0.37+0.39±0.44)×10-6, B(ηc→pΛ¯K-+c.c.)=(2.83-0.34+0.36±0.35)×10-3 and B(B+→pΛ¯ϕ)=( 7.95±2.09±0.77)×10-7, where c.c. denotes the corresponding charge-conjugation process. The intermediate resonance decays are excluded in the four-body decay measurements. We also find evidence for B(ηc→Λ(1520)Λ¯+c.c.)=(3.48±1.48±0.46)×10-3 and B(B+→Λ(1520)Λ¯K+)=( 2.23±0.63±0.25)×10-6. No significant signals are found for J/ψ→Λ(1520)Λ¯+c.c. and B+→Λ¯(1520)ΛK+; we set the 90% confidence level upper limits on their decay branching fractions as <1.80×10-3 and <2.08×10-6, respectively
Evidence for B+ -> h(c)K(+) and observation of eta(c()2S) -> p(p)over-bar pi(+)pi(-)
No full textA search for the decays B+ -> h(c)K(+) and B-0 -> h(c)K(S)(0) is performed. Evidence for the decay B+ -> h(c)K(+) is found; its significance is 4.8 sigma. No evidence is found for B-0 -> h(c)K(S)(0). The branching fraction for B+ -> h(c)K(+) is measured to be (3.7(-0.9 -0.8)(+1.0 +038)) x 10(-5); the upper limit for the B-0 -> h(c)K(S)(0) branching fraction is 1.4 x 10(-5) at 90% C. L. In addition, a study of the p (p) over bar pi(+pi-) invariant mass distribution in the channel B+ -> (p (p) over bar (+)pi(-))K+ results in the first observation of the decay eta(c)(2S) -> p (p) over bar pi(+)pi(-) with 12.1 sigma significance. The analysis is based on the 711 fb(-1) data sample collected by the Belle detector at the asymmetric- energy e(+)e(-) collider KEKB at the gamma(4S) resonance.SPCThis is an open access article under the terms of the Creative Commons Attribution Licens
Digital platformisation as public sector transformation strategy: a case of Ghana’s paperless port
No full textPublic sector organisations around the world are deploying digital platforms as part of their transformational strategy. However, prior research has predominantly focused on developed economies with stable institutional environments, while limited studies exist on less developed economies. Notwithstanding the digital divide, institutional voids, economic and development challenges facing less developed economies, digital platformisation as a strategy is fuelling technology leapfrogging in public sector transformation. Drawing on a case study of Ghana’s paperless port digital transformation and the technology affordance theory, we address the research question: “How can digital platformisation facilitate public sector transformation?” Based on the findings and the technology affordance theory, this study develops a transformational affordance framework (TAF) and offers propositions on how digital platforms can enable public sector transformation
Testing the weak-form efficiency in African stock markets
No full text<p>Purpose – The purpose of this paper is to investigate and compare the weak-form efficiency of a set of 24 African continent-wide stock price indices and those of eight individual African national stock price indices.</p>
<p>Design/methodology/approach – Variance-ratio tests based on ranks and signs were used to examine the weak-form efficiency of the 32 stock price indices investigated.</p>
<p>Findings – On average, it was found that irrespective of the test employed, the returns of all the 24 African continent-wide stock price indices examined in the study are less non-normally distributed compared to the eight individual national stock price indices examined. The authors also report evidence of the African continent-wide stock price indices having significantly better weak-form informational efficiency than their national counterparts.</p>
<p>Practical implications – The policy implication of this evidence is that the African equity price discovery process can be significantly improved if African stock markets integrate their operations. Economically, this may contribute to improved liquidity and more efficient allocation of capital, which in turn can be expected to have a positive impact on economic growth.</p>
<p>Originality/value – The paper makes two major contributions to the extant literature. First, it offers for the first time a comparative analysis of the informational efficiencies of a sample of national stock price indices as against African continent-wide stock price indices. Second, there is no prior evidence as to whether African stock markets can improve their informational efficiencies by integrating their operations. The paper fills this gap by demonstrating that the African equity price formation process can be improved if African stock markets integrate their operations.</p>
The impact of COVID-19 on managing product returns in retail
No full textThe Covid-19 pandemic has affected customers' shopping and returns behaviour and significantly aggravated the problem of high product returns rates and returns fraud. Measures for public health and safety resulted in retailers modifying their returns processes. The effects of these changes on returns management are unclear; very little is known about what retailers have experienced in terms of product returns during the pandemic. This paper addresses this research gap via a series of semi-structured interviews and a consumer survey. Our findings include a list of recommendations for retailers to mitigate the effects of the pandemic on returns and related fraud
Search for and branching fraction measurement of
No full textWe have searched for the Cabibbo-suppressed decay in collisions using a data sample corresponding to an integrated luminosity of 915 . The data were collected by the Belle experiment at the KEKB asymmetric-energy collider running at or near the and resonances. No significant signal is observed, and we set an upper limit on the branching fraction of at 90% confidence level. The contribution for nonresonant decays is found to be consistent with zero and the corresponding upper limit on its branching fraction is set to be at 90% confidence level. We also measure the branching fraction for the Cabibbo-favored decay ; the result is , which is the most precise measurement to date. Finally, we have searched for an intermediate hidden-strangeness pentaquark decay . We see no evidence for this intermediate decay and set an upper limit on the product branching fraction of at 90% confidence level
Going Beyond Counting First Authors in Author Co-citation Analysis
No full textThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
The pp -> p Lambda K(+) and pp -> p Sigma(0)K(+) reactions with chiral dynamics
No full textWe report on a theoretical study of the pp->p Lambda K+ and pp->p Sigma0 K+ reactions near threshold using a chiral dynamical approach. The production process is described by single-pion and single-kaon exchange. The final state interactions of nucleon-hyperon, K-hyperon and K-nucleon systems are also taken into account. We show that our model leads to a fair description of the experimental data on the total cross section of the pp->p Lambda K+ and pp->p Sigma0 K+ reactions. We find that the experimental observed strong suppression of Sigma0 production compared to Lambda production at the same excess energy can be explained. However, ignorance of phases between some amplitudes does not allow to properly account for the nucleon-hyperon final state interaction for the pp->p Sigma0 K+ reaction. We also demonstrate that the invariant mass distribution and the Dalitz plot provide direct information about the Lambda and Sigma0 production mechanism, and can be tested by experiments at COSY or HIRFL-CSR
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