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The Corona virus disease 2019 (COVID-19) health crisis has not spared any country in the world, from the most advanced to the poorest. COVID-19 pandemic has exposed much vulnerability in systems and societies. In all resource-constrained countries, the response has been very complicated. The pandemic had to be dealt with very quickly with limited health and economic resources to avoid the hecatomb already predicted for these countries. In Côte d'Ivoire in particular, health and government authorities worked with state or private structures with infrastructure and human resource capacities to develop a rapid and effective response plan. Several measures have been adopted to reduce the spread of COVID-19. As a result of all these strategies, the number of cases of infected persons has been gradually decreasing. This new situation has favored the revision of certain restrictive measures, in this case the closure of air borders, which have of course been eased under certain conditions. Travelers are required to have a paper attesting to their negativity in COVID-19 test. Thus, Pasteur Institute of Côte d'Ivoire (IPCI), the reference laboratory for carrying out COVID-19 tests, was responsible for supplying a certificate of analysis to travellers. The purpose of this article is to show the internal process developed and different strategies implemented by IPCI to establish and deliver this document in order to meet the demand in the context of a pandemic.

The object of this study is to estimate the diversity and the influence of the climate changes on spatial of the species of the family of Acanthaceae in Ivory Coast. Fluctuations in climatic variables such as precipitation and temperature are likely to affect biodiversity and the geographical distribution of habitats favourable to species. The principle of «Maximum Entropy» was used to model the habitats of Dicliptera alternans Lindau, Elytraria ivorensis Dokosi and of Whitfieldia lateritia Hook. under the current and future climatic conditions (horizon 2050/scenario A2). These species were selected on the one hand on the basis of number of occurrences and on the other hand by taking account of their endemic nature. The contact of presence of the species was collected and combined with the bioclimatic data extracted the database www.worldbioclim.org. The surface of the potentially favorable zones of distribution or not, was calculated for each species. The document retrieval revealed a total of 106 species left again between 39 kinds and of which 16% are endemic at the Ivory Coast. 7 species are register on the local list of the endangered species and rare of the Ivory Coast of Ake-Assi L. Les values of the AUC of about 0.90 indicate excellent quality of the models generated for the distribution of the model species by 2050, the results reveal that the «Seasonal variation of the temperature (Bio 4) » is the environmental variable which contributed the most to the prediction of the model of the species Dicliptera alternans Lindau, Elytraria ivorensis Dokosi and Whitfieldia lateritia Hook. The A2 scenario shows by a 2050 reduction of the surface of the potentially favorable zones of the species will des Dicliptera alternans Lindau, Elytraria ivorensis Dokosi and Whitfieldia lateritia Hook respectively of 67.66%, 3.35% and of 1.17%. In spite of these changes observed, the results show that the protected areas in Ivory Coast remain refuges under the current and future environmental conditions for the species of the family of Acanthaceae. This study confirms the impact proven of the climate changes on the spatiotemporelle distribution of the species. This work will help to better guide decision making in terms of conservation and management of protected areas as biodiversity refuges.

La presente etude a pour objectif principal d’evaluer la diversite et l’influence des changements climatiques sur la distribution spatiale des especes de la famille des Acanthaceae en Cote d’Ivoire. Le principe de « Maximum Entropie » a ete utilise pour modeliser les habitats de Dicliptera alternans Lindau, Elytraria ivorensis Dokosi et de Whitfieldia lateritia Hook. sous les conditions climatiques actuelles et futures (horizon 2050/scenario A2). Ces especes ont ete choisies d’une part sur la base du nombre d’occurrences et d’autre part en tenant compte de leur caractere endemique. Les coordonnees de presence des especes ont ete collectees et combinees aux donnees bioclimatiques extraites de la base de donnees www.worldbioclim.org. La superficie des zones de distribution potentiellement favorables ou non, a ete calcule pour chaque espece. La recherche documentaire a revele un total de 106 especes reparties en 39 genres dont 16% sont endemiques a la Cote d’Ivoire. 17 especes a statut particulier dont 9 figurent sur la liste rouge de l’UICN et 8 pour la liste locale des especes menacees et rares ivoiriennes de Ake-Assi L. Les valeurs de l’AUC (Area Under the Curve) de l’ordre de 0,90 indiquent une excellente qualite des modeles generes pour la distribution des especes modeles. a l’horizon 2050, les resultats revelent que la «Saisonnalite de la temperature (Bio 4) » est la variable environnementale qui a le plus contribue a la prediction du modele des especes Dicliptera alternans Lindau, Elytraria ivorensis Dokosi et Whitfieldia lateritia Hook. Le scenario A2 projette a l’horizon 2050 une reduction de la surface des zones potentiellement favorables des especes des Dicliptera alternans Lindau, Elytraria ivorensis Dokosi et Whitfieldia lateritia Hook respectivement de 67,66%, 3,35% et de 1,17%. Malgre ces changements observes, les resultats montrent que les aires protegees en Cote d’Ivoire demeurent des refuges sous les conditions environnementales actuelles et futures pour les especes de la famille des Acanthaceae. Cette etude confirme l’impact avere des changements climatiques sur la distribution spatiotemporelle des especes. © 2019 International Formulae Group. All rights reserved Mots cles: Diversite biologique, changement climatique, Scenario A2, Acanthaceae, Cote d’Ivoire English Title: Biological diversity and influence of the climate changes on the geographical distribution of some species of Acanthaceae in Ivory Coast English Abstract The object of this study is to estimate the diversity and the influence of the climate changes on spatial of the species of the family of Acanthaceae in Ivory Coast. The principle of «Maximum Entropy» was used to model the habitats of Dicliptera alternans Lindau, Elytraria ivorensis Dokosi and of Whitfieldia lateritia Hook. under the current and future climatic conditions (horizon 2050/scenario A2). These species were selected on the one hand on the basis of number of occurrences and on the other hand by taking account of their endemic nature. The contact of presence of the species was collected and combined with the bioclimatic data extracted the database www.worldbioclim.org. The surface of the potentially favorable zones of distribution or not, was calculated for each species. The document retrieval revealed a total of 106 species left again between 39 kinds and of which 16% are endemic at the Ivory Coast. 7 species are register on the local list of the endangered species and rare of the Ivory Coast of Ake-Assi L. Les values of the AUC of about 0.90 indicate excellent quality of the models generated for the distribution of the model species. by 2050, the results reveal that the «Seasonal variation of the temperature (Bio 4) » is the environmental variable which contributed the most to the prediction of the model of the species Dicliptera alternans Lindau, Elytraria ivorensis Dokosi and Whitfieldia lateritia Hook. The A2 scenario shows by a 2050 reduction of the surface of the potentially favorable zones of the species will des Dicliptera alternans Lindau, Elytraria ivorensis Dokosi and Whitfieldia lateritia Hook respectively of 67.66%, 3.35% and of 1.17%. In spite of these changes observed, the results show that the protected areas in Ivory Coast remain refuges under the current and future environmental conditions for the species of the family of Acanthaceae. This study confirms the impact proven of the climate changes on the spatiotemporelle distribution of the species. © 2019 International Formulae Group. All rights reserved Keywords: Biological diversity, climate change, A2 Scenario, Acanthaceae, Ivory Coast

We studied the possibility of producing seedlings of Thunbergia atacorensis (Acanthaceae) starting from cuttings under controlled cultivation conditions during 3 months. The objective of this work is to determine the optimal conditions for seedling production Thunbergia atacorensis by vegetative reproduction to allow its extension from professional growers and amateur (consumers). The study consisted to analyze their effect the plant growth, seedlings development, and leaves production. At the end the study, we obtained a rate of 91p.c for vegetative recovery for the cutting in shade 97p.c. for the cutting exposing to sun. However, the cuttings exposed sun clearly dissociates cuttings exposed to the shade with a shorter time of recovery. At the end of 3 months, only the sunny seedlings survive despite of the recovery rate of recovery. The study showed that the four environmental factors, the mode of exposure (sun and shade) and time (weeks) have a significant influence on the height and the number of seedlings leaves. The highest seedlings are observed in the shade from weeks 1 to 3. From week 3, only the sunny seedlings continue their growth and their development. The variation of the substrate and the frequency of watering, meanwhile, had no significant influence on the height and number of leaves. In sum, despite of lack of flowering, to produce seedlings of Thunbergia atacorensis, one should initially carry out the propagation by cutting in the shade and then to gradually intensify the light to have well developed seedlings.

We have developed and demonstrated a novel technique to manufacture very long gratings with a nearly arbitrary reflectivity profile. The technique is based upon writing a set of consecutive subgratings with interferometric control of the relative position of each subgrating.

We propose a model for designing and analyzing rare-earth-doped distributed-feedback (DFB) lasers. The effects of pump depletion and cross-gain saturation are included and shown to be significant for high-efficiency lasers. Our simulations show good agreement with experimental data from an ytterbium-doped fiber laser. We also give some design guidelines for DFB fiber lasers.

Recent findings strongly suggest that the glass in the core of a fiber optic Bragg grating has been periodically compacted resulting not only in residual tension but also in a structural transverse isotropy within the core of the fiber. These effects result in a difference of strain- temperature dependence within and outside the Bragg grating that provides a tool for separation of measurands. Hence temperature compensation can be achieved for a Fabry-Perot interferometer with chirped Bragg gratings as end reflectors when used in conjunction with a pulsed light source. The analysis presents in this paper show that if carefully chirped gratings are used as reflectors in a Fabry-Perot interferometer it is possible to control the optical path imbalance of the sensor such that one measurand can be fully compensated for, e.g. strain or temperature. Mainly temperature compensation is treated since it is considered the primary objective, even though the concept applies for any arbitrary measurand. Several relationships are derived for temperature compensation of Fabry-Perot interferometers with chirped Bragg grating reflectors including both free and embedded sensors. The boundary conditions of an embedded sensor are significantly altered since the surrounding host material superimposes temperature induced and transverse strains that will contribute substantially to the strain field inside the sensor. Simulations were carried out according to a geometric grating model assuming continuous chirp and a strict geometrical reflection criterion. These simulations are illustrating the compensation effect for various load cases to both free sensors and sensors embedded in composite laminates.

It is possible to induce second order nonlinear effects in glass systems, such as fibres, films or bulk silica samples by recording a permanent electric field optically, or by poling the samples with high voltages and heat. Characterising the charge distribution is central to understanding the mechanisms involved. We recently imaged frequency doubling gratings in fibres previously prepared for SHG, by etched the fibres until close to the core. Due to the presence of charges, etching is nonuniform, and the period of the grating can be unambiguously identified. Here, we present a simple technique to determine the charge distribution in poled glasses with submicron resolution. An interference pattern was formed by the reflections of a HeNe beam on the faces of a 1 mm thick poled slice of SiO2(3 KV, 280 °C). One of the faces was etched in HF, while the other was used as a reference, and the intensity of one fringe was monitored in real time. The optical path of the light reflected off the surface being etched was altered. When the glass was not poled, the etching rate was constant and a periodic variation of the fringe intensity was seen. When the glass was poled, a strong frequency modulation was observed. Positive charge resulted in slower etching, and negative charge caused faster etching [1].

We have developed and demonstrated a novel technique to manufacture very long and superstructured gratings based on writing a set of consecutive subgratings with interferometric control of the relative position between the subgratings.

A diode pumped Yb3+ DFB fibre laser comprising a single 10 cm Bragg grating with a permanent π/2 phase shift has been demonstrated. The DFB laser operates at 1047 nm with an in-fibre pump threshold < 230 µW and a 44% one-way slope efficiency. DFB operation was demonstrated using the heat-scan technique.

Chirped Bragg gratings in fibres have been characterised and mapped by scanning a heating element along the fibre. The chirp of three gratings was found to be linear, and a standard deviation as small as 6.6 pm has been measured.