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International audience; Seagrass meadows and their associated biodiverse assemblages have declined globally due to environmental and anthropogenic stressors. Restoration of these critical habitats has the potential to reverse coastal biodiversity loss. Here, we tested the role of patch size (which can affect recruitment, food availability, and/or predation) in driving faunal colonization in an eelgrass (Zostera marina) restoration trial in Sweden. Eelgrass shoots were transplanted in plots with different configurations (continuous vs. checkerboard patterns with three patch sizes), and we followed invertebrate colonization (biodiversity and functional diversity) during the first two growing seasons. We found rapid faunal colonization following the transplantation of eelgrass shoots in all plots with invertebrate densities reaching 50-80% of the reference meadow after only one growing season (3 months). After two growing seasons (15 months), the faunal density, biodiversity, and functional diversity were similar to the reference meadow, despite eelgrass density and biomass still being lower than the reference meadow. Biodiversity, functional diversity, and community structure were similar among the different planted plots, that is, there was no indication that patch size influenced faunal colonization. We therefore consider that smaller patches embedded within larger restoration plots can be as effective for promoting biodiversity as continuous patches, with reduced costs and fewer shoots required. We also noted high natural variability between years both in the reference meadow and planted plots, showing the dynamic nature of seagrass ecosystems, and the importance of a well-planned monitoring scheme that considers the reference area and restored area within the same temporal scale.

Numerous resilience measurement frameworks for climate programmes have emerged over the past decade to operationalise the concept and aggregate results within and between programmes. Proxies of resilience, including subjective measures using perception data, have been proposed to measure resilience, but there is limited evidence on their validity and use for policy and practice. This article draws on research on the Decentralising Climate Funds project of the Building Resilience and Adaptation to Climate Extremes and Disasters programme, which supports communities in Mali and Senegal to improve climate resilience through locally controlled adaptation funds. It explores attributes of resilience from this bottom‐up perspective to assess its predictors and alignment with food security, as a proxy of well‐being. We find different patterns when comparing resilience and the well‐being proxy, illustrating that the interplay between the two is still unclear. Results also point to the importance of contextualising resilience, raising implications for aggregating results.

Variants in FA2H have been associated with a wide range of phenotypes including hereditary spastic paraplegia type 35 (SPG35); however, genetically confirmed cases have not been reported in Africa. We report here the first African family with a variant in the FA2H gene causing SPG35. Four affected siblings with consanguineous parents presented with walking difficulty at age 2-3 and progressive limb weakness. They became wheelchair-bound two years after disease onset. Neurological examination confirmed lower greater than upper limb weakness and atrophy, brisk reflexes throughout, and spasticity with scissor legs. The patients also had choking, urinary urgency and mental retardation. A brain MRI showed thin corpus callosum and periventricular leucodystrophy. Testing of 58 SPG genes showed a homozygous variant in FA2H at the exon 5 donor site c.786+1G>A, which has previously been shown to cause skipping of exons 5 and 6 of the gene transcript. This variant segregated with the disease in the family. This variant has been reported previously with a similar phenotype and slow progression in a population with different background. Here we confirm its pathogenicity and expand its genetic epidemiology. Studying diverse populations may help to increase understanding of the disease mechanism and ultimately lead to therapeutic targets.

Objective Spinal muscular atrophy (SMA) is one of the most common severe hereditary diseases of infancy and early childhood in North America, Europe, and Asia. SMA is usually caused by deletions of the survival motor neuron 1 (SMN1) gene. A closely related gene, SMN2, modifies the disease severity. SMA carriers have only 1 copy of SMN1 and are relatively common (1 in 30–50) in populations of European and Asian descent. SMN copy numbers and SMA carrier frequencies have not been reliably estimated in Malians and other sub-Saharan Africans. Methods We used a quantitative polymerase chain reaction assay to determine SMN1 and SMN2 copy numbers in 628 Malians, 120 Nigerians, and 120 Kenyans. We also explored possible mechanisms for SMN1 and SMN2 copy number differences in Malians, and investigated their effects on SMN mRNA and protein levels. Results The SMA carrier frequency in Malians is 1 in 209, lower than in Eurasians. Malians and other sub-Saharan Africans are more likely to have ≥3 copies of SMN1 than Eurasians, and more likely to lack SMN2 than Europeans. There was no evidence of gene conversion, gene locus duplication, or natural selection from malaria resistance to account for the higher SMN1 copy numbers in Malians. High SMN1 copy numbers were not associated with increased SMN mRNA or protein levels in human cell lines. Interpretation SMA carrier frequencies are much lower in sub-Saharan Africans than in Eurasians. This finding is important to consider in SMA genetic counseling in individuals with black African ancestry. Ann Neurol 2014;75:525–532

Background and aim The use of skin bleaching products for cosmetic purposes is a frequent practice (25-96%) in women from sub-Saharan Africa. The dermatologic complications associated with this practice have been comprehensively reported. The aim of this work was to study the epidemiologic, clinical, and cosmetic aspects of these complications in order to produce better therapeutic guidelines for their management. Methods This was a prospective, descriptive study performed over a 6-month period. All women aged between 15 and 50 years, who consulted a dermatologist (Le Dantec Hospital or Institute of Social Hygiene), experienced a complication associated with artificial depigmentation, and agreed to take part in the study, were included. The data were input and analyzed using Epi info version 6.0. Results Eighty-six female patients were included, with a mean age of 29.34 years (range, 16-49 years). The breakdown by level of education was as follows: primary (48.8%), secondary (18.3%), and higher (8.5%) education. Twenty-two per cent of our population had not attended school. The mean monthly cost of skin bleaching products was 6.22 euros. The initial skin tone before using skin bleaching products was black in 41.5% of patients, light in 32.9%, and intermediate in 25.6%. The mean duration of exposure was 6.7 ± 5 years (range, 1-30 years). The breakdown by skin bleaching products showed that topical corticosteroids were the most frequently used (78%), followed by hydroquinone (56%), products based on vegetable extracts (31.7%), caustic products (8.5%), and, finally, products of unknown composition (41.4%).Two components or more were frequently combined (86.5%). The aesthetic complications of artificial depigmentation were the reason for consulting a dermatologist in 10 patients (12%). Nineteen types of aesthetic complication were reported in our sample. Hyperpigmentation of the joints was the most frequently found complication (85.4%), followed by striae atrophicae (72%) and skin atrophy (59.8%). The number of aesthetic complications found in the patients varied from one to nine. Patients frequently presented (71.9%) with other complications associated with artificial depigmentation. Conclusions Aesthetic complications associated with artificial depigmentation are common, but rarely the reason for consulting a dermatologist. In the absence of suitable therapeutic agents, prevention, based on informing women of the damaging effects of artificial depigmentation, is the only way forward.

The reaction of aromatic and aliphatic imines derived from (S)-valine methyl ester and (S)-valinol with allyl bromide and zinc in tetrahydrofuran affords homoallylic amines with up to 100% diastereoisomeric excess (d.e.), but in the case of the aromatic imines the diastereoselectivity is lowered by increasing the reaction time, owing to the reversibility of the allylation reaction.

Grignard and Barbier procedures have been applied to the addition of allylmetal (Zn, Cu, Pb, Bi, Al, In) species to imines derived from @)-valine esters, principally the methyl ester. The Zn-mediated, CeC13or SnClz-catalyzed "Barbier" reactions of the imines with allyl bromide in THF in Ar atmosphere a t room temperature proved particularly convenient, efficient and selective, providing the secondary homoallylic amines with excellent to perfect diastereoselectivity. The si face of the imine was attacked preferentially in every case. The addition of allylzinc bromide to aromatic imines was affected by reversibility, which caused the lowering of the diastereoisomeric ratio with increasing the reaction time. However, the retroallylation reaction could be avoided by performing the reaction in the presence of trace amounts of water, or by using CeC13-7Hz0 as the catalyst, although a t the expense of the reaction rate. The bimetal redox systems Al-PbBrz, -SnClZ, -TiC14, and -BiCl3 were applied to the allylation of the imines derived from methyl valinate, but satisfactory results were achieved only with Al-BiC13 and -Tic14 systems. However, the use of the Al(Hg) and Al-PbBrz system afforded almost perfect chemoand diastereoselectivity on the benzaldehyde imine derived from tert-butyl (SI-valinate. The synthesis of (S)-l-phenyl-3-butenamine from the corresponding secondary homoallylic amine was accomplished by a two-step sequence, consisting of the controlled reduction of the methyl ester with LMH4 and subsequent oxidative cleavage with H5106-MeNHz.

One well documented method for finding the fractal dimension of a silhouette involves approximating the silhouette with polygons which have all but one side equal and the vertices of which fall upon the silhouette edge. These are constructed using a divider stepping method or a computer algorithm which mimics this process. If one does not complete the polygon with an unequal side, as is usually done, but continues the analysis by stepping around the silhouette several times, the dividers start to „walk in their own footsteps” and describe an equilateral polygon in the silhouette. These phenomena, termed polygonal harmonics, are examined and discussed in detail. A rule is developed for harmonic stability and specific cases of the circle, triangle and smooth curves are examined to gain insight into the convergence process.