RESUMEN

COVID-19, the novel coronavirus, has posed a major threat to low- and middle-income countries (LMICs) due to inadequate health infrastructure and human resources. Ethiopia, a low-income country with the second largest population in Africa, has coordinated a strategic response, leveraging existing infrastructure and health systems and mobilizing public health professionals and specialist expert physicians for a multifaceted, unified government approach and adaptive response. Resource limitations, particularly in critical care, have still posed challenges, but the public health and clinical interventions thus far have prevented the catastrophic toll that many predicted. As the pandemic continues, Ethiopia expects to use a triple care model integrated at all levels, consisting of COVID-19 care, isolation care for suspected cases, and essential health services, and urges intensified non-pharmaceutical interventions alongside equitable global vaccine distribution as the ultimate answers to pandemic control. This paper draws on existing data, national planning and guidelines, and expertise from health leadership to describe this response in hopes of providing an example of how future large-scale health challenges might be faced in LMICs, using Ethiopia's successes and challenges in facing the pandemic.

COVID-19, le nouveau coronavirus, a représenté une menace majeure pour les pays à revenu faible et intermédiaire (LMIC) en raison de l'insuffisance des infrastructures de santé et des ressources humaines. L'Éthiopie, un pays à faible revenu dont la population est la deuxième plus importante d'Afrique, a coordonné une réponse stratégique, en tirant parti des infrastructures et des systèmes de santé existants et en mobilisant des professionnels de la santé publique et des médecins experts spécialisés pour une approche gouvernementale unifiée à multiples facettes et une réponse adaptative. Les ressources limitées, notamment en matière de soins intensifs, ont encore posé des problèmes, mais les interventions cliniques et de santé publique menées jusqu'à présent ont permis d'éviter le bilan catastrophique que beaucoup prédisaient. Alors que la pandémie se poursuit, l'Éthiopie prévoit d'utiliser un modèle de soins triple intégré à tous les niveaux, composé de soins COVID-19, de soins d'isolement pour les cas suspects et de services de santé essentiels, et préconise l'intensification des interventions non pharmaceutiques parallèlement à une distribution équitable des vaccins à l'échelle mondiale comme réponses ultimes au contrôle de la pandémie. Cet article s'appuie sur les données existantes, la planification et les directives nationales, et l'expertise des responsables de la santé pour décrire cette réponse dans l'espoir de fournir un exemple de la manière dont les futurs défis sanitaires à grande échelle pourraient être relevés dans les LMIC, en utilisant les succès et les défis de l'Éthiopie face à la pandémie.

RESUMEN

The ultrafast relaxation pathways in a hexaiodide bismuth(III) complex, BiI63-, excited at 530 nm in acetonitrile solution are studied by means of femtosecond transient absorption spectroscopy supported by steady-state absorption/emission measurements and DFT computations. Radiationless relaxation out of the Franck-Condon, largely metal-centered (MC) triply degenerate 3T1u state (46 ± 19 fs), is driven by vibronic coupling due to the Jahn-Teller effect in the excited state. The relaxation populates two lower-energy states: a ligand-to-metal charge transfer (LMCT) excited state of 3π I(5pπ) → Bi(6p) nature and a luminescent "trap" 3A1u(3P0) MC state. Coherent population transfer from the initial 3T1u into the 3π LMCT state occurs in an oscillatory, stepwise manner at ∼190 and ∼550 fs with a population ratio of ∼4:1. The 3π LMCT state decays with a 2.9 ps lifetime, yielding two short-lived reaction intermediates of which the first one reforms the parent ground state with a 15 ps time constant, and the second one decays on a ∼5 ps timescale generating the triplet product species, which persists to the longest 2 ns delay times investigated. This product is identified as the η2 metal-ligated diiodide-bismuth adduct with the intramolecularly formed I-I bond, [(η2-I2)Bi(II)I4]3-, which is the species of interest for solar energy conversion and storage applications. The lifetime of the "trap" 3A1u state is estimated to be 13 ns from the photoluminescence quenching of BiI63-. The findings give insight into the excited-state relaxation dynamics and the photochemical reaction mechanisms in halide complexes of heavy ns2 metal ions.

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RESUMEN

The population and structural dynamics of IrCl62- is studied in acetonitrile and aqueous solutions in comparison to isoelectronic IrBr62- using ultrafast broadband, dispersed transient absorption, with both octahedra excited with 85 fs pulses at four different wavelengths, encompassing the first seven t2g-based electronic states. Ligand-to-metal charge transfer (LMCT) 420 or 490 nm excitation of IrCl62- into Uu'(2T2u) + Eu''(2T2u) states, superimposed due to Ham effect, or Uu'(2T1u), respectively, leads to symmetry lowering due to Jahn-Teller effect in these excited states with the subsequent 100 fs decay into Ug'(2T1g). This first LMCT state is formed vibrationally coherent in the 104 cm-1 t2g (scissor) or 243 cm-1 eg (out-of-phase-stretch) Jahn-Teller modes for the respective excitation wavelength. Direct excitation into Ug'(2T1g) at 600 nm and the intraconfigurational lowest excited Ug'(2T2g) state at 1900 nm helped to establish that Ug'(2T1g) decays via back electron transfer into Ug'(2T2g) (time constants, 3.55 ps in acetonitrile and 0.9 ps in water), and the decay of Ug'(2T2g) into the ground state is the rate-limiting relaxation step. The relaxation cascade of IrBr62- is similar with short-lived (≤100 fs) higher LMCT states, but the vibrational coherence is only observed in the Jahn-Teller t2g mode. Faster back electron transfer for IrBr62- is explained by the energy gap law. The intraconfigurational Ug'(2T2g) states, which are ∼5100 cm-1 above the ground state for both complexes, have a sub-nanosecond lifetime largely independent of the ligand nature (∼350 ps, acetonitrile).

RESUMEN

Anthelmintic treatment (A), feed supplementation (F), anthelmintic and feed supplementation (A+F) or traditional management (Control) was given to 166 pregnant female donkeys in three localities (Holetta, Debre Zeit and Adami Tulu) in Ethiopia during an on-farm study. Treatments started during the last trimester of pregnancy and continued until 6 months after parturition when the foals were weaned. The same treatments were administered to foals once they reached 1 month of age. Live weights of adults and foals were measured throughout the study along with work output of adult donkeys and survival to weaning of the foals. Faecal worm egg counts (FEC) and blood packed cell volumes (PCV) were recorded monthly. When applied alone, anthelmintic treatment (A) or feed supplementation (F) had no significant effect on live weight gain or foal survival. However, when combined, anthelmintic and feed supplementation (A+F) significantly (p<0.05) improved both live weight gain in adults and foals and foal survival. Workout was not affected by any of the treatments. Treatments A and A+F resulted in a highly significant (p<0.001) reduction in FEC in all three localities during the course of study and for at least 6 months after the last dose of anthelmintic in one of the study areas (Holetta). None of the treatments had any significant effect on PCV. Donkey owners in Ethiopia should be encouraged to adopt both anthelmintic treatment and feed supplementation if they expect tangible benefits in animal performance.

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RESUMEN

A survey of donkeys arriving at markets in three localities in East and West Shewa regions of central Ethiopia was carried out during 2002. Total faecal worm egg counts and body condition scores were measured for a total of 963 donkeys over a 12-month period. Total faecal worm egg counts did not differ significantly between localities but there was significant (p < 0.001) seasonal variation within localities. Levels of helminth infection closely followed rainfall patterns, being lowest (956 eggs per gram of faeces, e.p.g.) at the end of the long dry season (February) and highest (2022 e.p.g.) in the middle of the long wet season (August). Body condition score was associated closely with level of helminth infection (Goodman-Kruskal measure of association 0.60-0.80). Seasonal variation in body condition score reflected the temporal changes in worm burden and the availability of forage. It is suggested that a body condition score of 3 or less could be used as a simple means of identifying donkeys that require therapeutic treatment with anthelmintic. It is further proposed that economically viable strategic control of helminths in donkeys could be achieved by administering a single annual dose of avermectin-based anthelmintic at the start of the long rainy season (May-June). This may allow donkeys to recover body condition when available forage is most abundant and nutritious. It is also recommended that protein-rich feed supplementation be provided during the later part of the dry season (November-January). This may help maintain body condition when forage is scarce and the helminth challenge is at its lowest.

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