Nuclear and nucleon transitions of the H di-baryon

We consider 3 types of processes pertinent to the phenomenology of an H di-baryon: conversion of two $\Lambda$'s in a doubly-strange hypernucleus to an H, decay of the H to two baryons, and -- if the H is light enough -- conversion of two nucleons in a nucleus to an H. We compute the spatial wavefunction overlap using the Isgur-Karl and Bethe-Goldstone wavefunctions, and treat the weak interactions phenomenologically. The observation of $\Lambda$ decays from doubly-strange hypernuclei puts a constraint on the H wavefunction which is plausibly satisfied. In this case the H is very long-lived as we calculate. An absolutely stable H is not excluded at present. SuperK can provide valuable limits

Decays of ℓ=1\ell=1 Baryons --- Quark Model versus Large-NcN_c

We study nonleptonic decays of the orbitally excited, \su6 \rep{70}-plet baryons in order to test the hypothesis that the successes of the nonrelativistic quark model have a natural explanation in the large-$N_c$ limit of QCD. By working in a Hartree approximation, we isolate a specific set of operators that contribute to the observed s- and d-wave decays in leading order in $1/N_c$. We fit our results to the current experimental decay data, and make predictions for a number of allowed but unobserved modes. Our tentative conclusion is that there is more to the nonrelativistic quark model of baryons than large-$N_c$.Comment: LaTeX 49pp. (38 pp. landscape), PicTex, PrePicTex, PostPicTex required for 3 figures, Harvard Preprint HUTP-94/A008. (Two additional operators are included, but conclusions are unchanged.

High concentration PV system

The aim of the European funded project HICON (High Concentration PV Power Systems) has been to develop, set up and test a new high concentration – 1000x or more – PV system. This system uses an actively cooled large-area receiver consisting of III-V solar cells. Two technology fields have been integrated: The high concentration of the sunlight has been obtained by using technologies experienced in solar thermal systems like parabolic dishes or tower systems. The high concentration photovoltaic receiver is based on the III-V solar cell technology. To deal with the high concentration, Monolithic Integrated Modules (MIMs) [1-3] have been further developed and assembled to Compact Concentrator Modules (CCM). The CCM prototypes have been tested in a solar furnace (PSA) and in a parabolic dish (BGU). The results of the project will be presented in this paper.peer-reviewe

Computerised cognitive assessment in patients with traumatic brain injury: an observational study of feasibility and sensitivity relative to established clinical scales

Background: Online technology could potentially revolutionise how patients are cognitively assessed and monitored. However, it remains unclear whether assessments conducted remotely can match established pen-and-paper neuropsychological tests in terms of sensitivity and specificity. Methods: This observational study aimed to optimise an online cognitive assessment for use in traumatic brain injury (TBI) clinics. The tertiary referral clinic in which this tool has been clinically implemented typically sees patients a minimum of 6 months post-injury in the chronic phase. Between March and August 2019, we conducted a cross-group, cross-device and factor analyses at the St. Mary's Hospital TBI clinic and major trauma wards at Imperial College NHS trust and St. George's Hospital in London (UK), to identify a battery of tasks that assess aspects of cognition affected by TBI. Between September 2019 and February 2020, we evaluated the online battery against standard face-to-face neuropsychological tests at the Imperial College London research centre. Canonical Correlation Analysis (CCA) determined the shared variance between the online battery and standard neuropsychological tests. Finally, between October 2020 and December 2021, the tests were integrated into a framework that automatically generates a results report where patients’ performance is compared to a large normative dataset. We piloted this as a practical tool to be used under supervised and unsupervised conditions at the St. Mary's Hospital TBI clinic in London (UK). Findings: The online assessment discriminated processing-speed, visual-attention, working-memory, and executive-function deficits in TBI. CCA identified two significant modes indicating shared variance with standard neuropsychological tests (r = 0.86, p < 0.001 and r = 0.81, p = 0.02). Sensitivity to cognitive deficits after TBI was evident in the TBI clinic setting under supervised and unsupervised conditions (F (15,555) = 3.99; p < 0.001). Interpretation: Online cognitive assessment of TBI patients is feasible, sensitive, and efficient. When combined with normative sociodemographic models and autogenerated reports, it has the potential to transform cognitive assessment in the healthcare setting. Funding: This work was funded by a National Institute for Health Research (NIHR) Invention for Innovation (i4i) grant awarded to DJS and AH ( II-LB-0715-20006)

Windborne long-distance migration of malaria mosquitoes in the Sahel

Over the past two decades efforts to control malaria have halved the number of cases globally, yet burdens remain high in much of Africa and the elimination of malaria has not been achieved even in areas where extreme reductions have been sustained, such as South Africa1,2. Studies seeking to understand the paradoxical persistence of malaria in areas in which surface water is absent for 3–8 months of the year have suggested that some species of Anopheles mosquito use long-distance migration3. Here we confirm this hypothesis through aerial sampling of mosquitoes at 40–290 m above ground level and provide—to our knowledge—the first evidence of windborne migration of African malaria vectors, and consequently of the pathogens that they transmit. Ten species, including the primary malaria vector Anopheles coluzzii, were identified among 235 anopheline mosquitoes that were captured during 617 nocturnal aerial collections in the Sahel of Mali. Notably, females accounted for more than 80% of all of the mosquitoes that we collected. Of these, 90% had taken a blood meal before their migration, which implies that pathogens are probably transported over long distances by migrating females. The likelihood of capturing Anopheles species increased with altitude (the height of the sampling panel above ground level) and during the wet seasons, but variation between years and localities was minimal. Simulated trajectories of mosquito flights indicated that there would be mean nightly displacements of up to 300 km for 9-h flight durations. Annually, the estimated numbers of mosquitoes at altitude that cross a 100-km line perpendicular to the prevailing wind direction included 81,000 Anopheles gambiae sensu stricto, 6 million A. coluzzii and 44 million Anopheles squamosus. These results provide compelling evidence that millions of malaria vectors that have previously fed on blood frequently migrate over hundreds of kilometres, and thus almost certainly spread malaria over these distances. The successful elimination of malaria may therefore depend on whether the sources of migrant vectors can be identified and controlled

Use of simple-harmonic forces in the non-relativistic quark model

Attention is drawn to a possible band structure displayed by the known N* resonances, The observed spectrum is similar to that predicted by a paraquark harmonic-oscillator shell model. "Exact three-body Schroedinger wave functions are used to compute the N~partial decay widths, assuming the pion emission takes place via a one-quark de-excitat~on, . The agreement with experiment is sufficiently good to warrant an investigation of the N* decay widths of all resonances predicted to havem' up to about 2 GeV, and such an investigation is performed. The model is then used to estimate the radiative widths of the observed N* resonances, In the "second resonance region" of pion photoproduction, both the Sll(1550) and D13(1525) resonances (and possibly the Dll(1470), depending on what should be taken as its Nn width) are expected to be important, while in the "third resonance region" F15(1690), Sll (1710) and D13(1990) are expected to have comparable contributions, The mixing angle between the two Sll resonances is determined to be about 350. In inelastic electron scattering ep -> eN*, the S11(155'0) and D13 (1525) resonances are expected to dominate over the Pll(1470). The neutral Pll(1470) radiative width is found to be smaller than the charged width, in contrast to an SU(3) 10 assignment for this resonance. The model is extended to include the strangeness-zero meson resonances, and the root mean square pion radius is found to be larger than that of the nucleon. The principal failures of the model are its inability to predict the correct shape for the nucleon electromagnetic form factors, and both the proton magnetic moment and the pion-nucleon coupling constant are predicted to be 40% larger than the experimental findings.U of I OnlyThesi