35 research outputs found

    Cocoa marketing chain in developing countries: how do formal-informal linkages ensure its sustainability in Cameroon?

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    Open Access Article; Published online: 10 Oct 2020Although liberalization of the cocoa sector has increased internal competition within the marketing chain it has also led to the emergence of informal market actors within the chain. Therefore, the aim of this paper is to analyse how the cocoa marketing chain operates by measuring and comparing the marketing margins of the formal and informal actors. Qualitative data were used to establish the structure of the marketing chain and quantitative data to estimate the marketing margins. A total sampling size of 76 cocoa market actors was obtained by using a multi-stage sampling technique: 15 for qualitative data and 61 for quantitative data. Descriptive analysis was used to map the marketing chain and economic analysis to compute the costs and margins for both informal and formal market intermediaries from the Centre and South-West regions in Cameroon. The results indicated three market intermediaries (one informal and two formal) and four marketing channels by which cocoa moves from the farmers to the exporters. The calculation of marketing costs indicated that informal actors incurred the highest costs in both regions. The results regarding the marketing margins were twofold: informal actors obtain low net marketing margins when they do not use illicit strategies, but high net marketing margins when illicit strategies are used. Given the significant role of informal actors, we suggest that their actions should be integrated in a suitable manner into those of formal actors to contribute to a better performance of the marketing chain and to the sustainability of the cocoa sector

    Heterogeneous Pattern of Retinal Nerve Fiber Layer in Multiple Sclerosis. High Resolution Optical Coherence Tomography: Potential and Limitations

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    BACKGROUND: Recently the reduction of the retinal nerve fibre layer (RNFL) was suggested to be associated with diffuse axonal damage in the whole CNS of multiple sclerosis (MS) patients. However, several points are still under discussion. (1) Is high resolution optical coherence tomography (OCT) required to detect the partly very subtle RNFL changes seen in MS patients? (2) Can a reduction of RNFL be detected in all MS patients, even in early disease courses and in all MS subtypes? (3) Does an optic neuritis (ON) or focal lesions along the visual pathways, which are both very common in MS, limit the predication of diffuse axonal degeneration in the whole CNS? The purpose of our study was to determine the baseline characteristics of clinical definite relapsing-remitting (RRMS) and secondary progressive (SPMS) MS patients with high resolution OCT technique. METHODOLOGY: Forty-two RRMS and 17 SPMS patients with and without history of uni- or bilateral ON, and 59 age- and sex-matched healthy controls were analysed prospectively with the high resolution spectral-domain OCT device (SD-OCT) using the Spectralis 3.5mm circle scan protocol with locked reference images and eye tracking mode. Furthermore we performed tests for visual and contrast acuity and sensitivity (ETDRS, Sloan and Pelli-Robson-charts), for color vision (Lanthony D-15), the Humphrey visual field and visual evoked potential testing (VEP). PRINCIPAL FINDINGS: All 4 groups (RRMS and SPMS with or without ON) showed significantly reduced RNFL globally, or at least in one of the peripapillary sectors compared to age-/sex-matched healthy controls. In patients with previous ON additional RNFL reduction was found. However, in many RRMS patients the RNFL was found within normal range. We found no correlation between RNFL reduction and disease duration (range 9-540 months). CONCLUSIONS: RNFL baseline characteristics of RRMS and SPMS are heterogeneous (range from normal to markedly reduced levels)

    Intravitreal Avastin for macular oedema secondary to retinal vein occlusion: a prospective study

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    OBJECTIVE: To evaluate efficacy and safety of intravitreal bevacizumab (Avastin) in eyes with macular oedema secondary to central retinal vein occlusion (CRVO) or branch retinal vein occlusion (BRVO). METHODS: Twenty-eight consecutive patients (28 patients, 29 eyes, 8 CRVO, 21 BRVO) were enrolled in the study. Three intravitreal injections of 1 mg bevacizumab (0.04 ml) were administered at 4-week intervals; further retreatment was based on optical coherence tomography (OCT) findings. Follow-up examinations were done at days 1, 7 and 28 and at monthly intervals thereafter. RESULTS: Mean baseline central retinal thickness (CRT) in OCT was 558 microm (range 353-928 microm) and mean BCVA was 20/100. One day after the first injection, CRT significantly decreased to 401 microm (p<0.01). Three injections reduced macular oedema to 328 microm CRT (p<0.01) and improved BCVA to 20/50 (p<0.01). At 6 months, CRT was 382 microm (p<0.01), and BCVA was stable at 20/50(-2) (p<0.01), FA showed no evidence of increased avascular zones. CONCLUSION: Intravitreal injections of bevacizumab appear to be a safe and effective therapy in the treatment of macular oedema secondary to retinal vein occlusion

    Natura 2000 and climate change—Polarisation, uncertainty, and pragmatism in discourses on forest conservation and management in Europe

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    European forests are a resource that is targeted by several EU environmental and land use policies as forests can be of critical importance to mitigate climate change. At the same time, they are central to the EU's biodiversity policy, and particular the Natura 2000 network of protected areas. Yet, the interlinkage between climate change and biodiversity policy is complex and discursively contested. In this paper, we assess how the debate on climate change adaptation affects forest conservation and management under Natura 2000. Drawing on the concept of argumentative discourse analysis, we present evidence from 213 qualitative interviews with policy stakeholders and practitioners that were conducted at both the European policy level and the local country level in 6 EU member states. Our results demonstrate that the nexus between climate change adaptation and forest conservation policy is conceptualised differently by different stakeholders and practioners at different levels. Three major discourses can be made out (pragmatic discourse, dynamics discourse, threat discourse), which are characterised by a set of partially overlapping story lines. These discourses are employed by four discourse coalitions (environmental, forest users’, expert, and grass root coalition). As a general rule, debates at the European level are more polarised and politicised, while the local debates on climate change and Natura 2000 remain rather vague and are less polarised. This seems to indicate that the link between climate change adaptation and forest conservation is mostly an issue for an abstract high-level policy debate. At this level, climate change is used to influence well-known policies, and to legitimise distinct interests that were already present before the climate change debate has emerged

    High-resolution optical coherence tomography

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