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Objectives Sickle cell disease (SCD) is the leading genetic disease in French Guiana, reflecting the predominantly African ancestry of the Guianese population. Our purpose was to characterize the genetic modulators of SCD in order to retrace the origin of the population in light of the slave trade. Methods We have studied the sickle cell genotype, the βS haplotypes, the alpha and beta thalassemia and the UGT1A1 promoter polymorphisms in 224 Guianese patients with SCD. Results The genotypes of SCD were HbSS 65.6%, HbSC 24.5%, and HbS-beta thalassemia 9.4%. The most frequent βS haplotypes were the Benin haplotype (65.9% of the chromosomes) and the Bantu (20.5%). Alpha thalassemic deletions were present in 37% of the patients and homozygosity for the (TA)7 allele of the UGT1A1 promoter in 21.4%. When the patients' origins were considered, 3 groups, Noir Marron, Haitians and Creoles, displayed distinctive characteristics. The HbSC genotype, the Benin haplotype, and the homozygous UGT1A1 genotype TA7/TA7 were significantly more frequent in Noir Marron. The Haitian patients were characterized by the occurrence of alpha-thalassemia and beta-thalassemia and by a higher prevalence of the Bantu haplotype. In the group of Creole patients, the genotype HbSS was predominant but the other modulators of SCD were associated with intermediate risk. Conclusions The results highlight the genetic diversity of the Guianese population and are concordant with historical data on the slave trade showing a West African origin for Noir Marron and a Central African origin for Haitians, while Guianese Creoles are highly admixed. Am. J. Hum. Biol., 2016. © 2016 Wiley Periodicals, Inc.

Six strains of bacteria including Bacillus mycoides (A10) and Shewanella species (A12) isolated from healthy marron intestine, Bacillus species (PM1), Bacillus subtilis (PM3), Bacillus sp. (PM4) and Bacillus sp. (AQ) from commercial probiotic products were investigated for probiotic potential in marron culture. Antibiotic susceptibility tests indicated PM3 and PM4 were susceptible to all nine antibiotics evaluated. A10, A12 and AQ were resistant to class penicillins, whereas PM1 was resistant to class penicillin and macrolides. All strains were non-pathogenic for marron. Strong inhibition against Vibrio mimicus and Vibrio cholerae non-01 was exhibited by PM4 and PM3. A10 inhibited V. mimicus at 72 h of growth, but not V. cholerae non-01, whereas A12 inhibited V. cholerae non-01 but not V. mimicus, and AQ showed no inhibition activity. A wide range of enzymes were produced by A10 and AQ using the API ZYM test. Protease enzymes were produced by PM3, PM4, AQ and PM1. In order of effectiveness, the following bacteria have probiotic potential: B. subtilis (PM3), Bacillus sp. (PM4) and B. mycoides (A10). Further study is required to determine the bacterium or any combination that gives a multibeneficial effect on marron.

This is a discussion of the paper "Overview of object oriented data analysis" by J. Steve Marron and Andres M. Alonso.

This is a discussion of the paper "Overview of object oriented data analysis" by J. Steve Marron and Andres M. Alonso.

This note is a discussion on the paper "Overview of object oriented data analysis," by J. Steve Marron and Andres M. Alonso.

The decline in freshwater crayfishes is occurring on a global scale. A gastronomic delicacy and a Western Australian freshwater icon, Cherax cainii (the smooth marron) is the third largest freshwater crayfish in the world and has been an important food source for the human inhabitants of southwestern Australia for tens of thousands of years. However, the species has disappeared from much of its historical range due to anthropogenic salinization of waterways, which has prompted interest and investigations into restoring the smooth marron's habitat. Severe and ongoing flow declines due to climate change‐related drought threaten to further exacerbate past environmental degradation of the region's watersheds. This will make the existing network of artificial reservoirs almost functionally obsolete as primary sources of drinking water but will not lead to the network's total elimination. Currently, the smooth marron thrives in these freshwater reservoirs. Harnessing these impoundments as arks to support the region's highly endemic and imperiled aquatic fauna represents a tangible, albeit controversial, way to maintain aquatic biodiversity in an area largely devoid of dam‐impacted migratory species. Habitat restoration strategies, such as providing logs and wood for shelter to protect the smooth marron from predation by birds and alien fishes, will be a crucial part of the solution. Are we willing to similarly prioritize the restoration of anthropogenic aquatic habitats and natural – though severely degraded – systems to conserve such iconic aquatic species? Such decisions regarding the allocation of restoration efforts remain hotly debated.

The efficacy of dietary supplementation of mannan oligosaccharide (MOS) (Bio-Mos®, Aqua Grade; Alltech, Lexington, KY, USA) was evaluated on survival, growth, physiological and immunological parameters of marron, Cherax tenuimanus. Marron were fed six different isonitrogenous and isocalorific diets supplemented with 0, 0.05, 0.1, 0.2, 0.4, and 0.8% of MOS for a duration of 112 d and examined for survival and growth every 28 d. Physiological and immunological indicators were measured every 56 d. After 112 d, survival was the highest when marron were fed 0.2 and 0.4% MOS supplemented diets. Wet tail muscle index (TMIwet) and dry tail muscle index (TMIdry) of marron fed MOS supplemented diets were significantly higher (P < 0.05) than marron fed diet without MOS. Osmoregulatory capacity was highest in marron fed 0.4% MOS. Marron fed MOS supplemented diets had lower (P < 0.05) bacteraemia than marron fed diet without MOS. Hemolymph clotting time was the lowest and granular cells were the highest in marron fed 0.2 and 0.4% MOS. The results suggest that feeding 0.2–0.4% MOS in the diet increases the health status of marron.

This is a discussion around the paper "Overview of object oriented data analysis" by J. Steve Marron and Andres M. Alonso.

Many valleys in Western Australia have been dammed to provide irrigation and potable water. To minimize the risks of outlet blockages, basins have been cleared of vegetation and rocky outcrops during construction. As a result, dam basins contain limited numbers of aquatic habitats, being dominated by sandy and muddy substrata. Nonetheless, endemic crayfishes (especially marron, Cherax tenuimanus) and three introduced species of fishes support large recreational fisheries in irrigation reservoirs. Recently, it has been shown that Perca fluviatilis (red-fin perch) imposes an extremely high mortality on C. tenuimanus in reservoirs, with the result that marron populations might be below reservoir-carrying capacity. To test this hypothesis, three types of artificial habitats (pipes, tiles, mesh) that mimic natural habitat types were placed into a reservoir and their use by C. tenuimanus was assessed. As C. tenuimanus is an annual brooder, releasing young during November and December, the effects of artificial habitats on biomass concentration and productivity can be differentiated. The study results showed that C. tenuimanus rapidly populated artificial habitats (concentration effects). Small, newly recruited C. tenuimanus also utilized the pipe and tile habitats (productivity effects). The addition of these types of habitats increased the suitability of the reservoir for the studied C. tenuimanus population, increasing productivity, probably via reduction of teleost predation. The increased productivity of the C. tenuimanus population might, in turn, increase the productivity and sustainability of the recreational marron fishery. Other aquatic species, including a biofilm community, also utilized the artificial habitats, increasing the species richness in the dam. Due to the success of the current study, large artificial habitats have been installed into two irrigation reservoirs in order to increase recreational marron fishing and conservation values.

Approximately 440 base pairs (bp) of the mitochondrial 16S ribosomal ribose nucleic acid (rRNA) coding region were sequenced from 13 marron, Cherax tenuimanus (Smith), samples from six locations and samples of two additional Cherax species from Western Australia. The results indicated that, with the exception of the Margaret River, no variation was found within or between marron populations. In contrast, marron from the Margaret River were found to be polymorphic for two divergent haplotypes (2.76% divergence). These findings were consistent with allozyme data that highlight the general lack of genetic variability within and between populations of this species apart from the Margaret River stocks. The genetic polymorphisms in the Margaret River stocks contrasted with earlier studies and indicated the recent translocation and mixing of genetically differentiated stocks within this river system. The implications of these findings for the conservation and management of genetic diversity within marron are discussed.

A review of approaches currently used to measure growth in freshwater crayfish under experimental and pond grow-out conditions is presented. The review examined 206 papers on growth and production of freshwater crayfish of which 34 were selected for detailed investigation. Selection was based on the amount of information provided in the published report and on the species studied. The review was restricted to six crayfish species: Cherax tenuimanus (marron), C. destructor (yabbie), C. quadricarinatus (red claw), Procambarus clarkii (red swamp crayfish), Astacus astacus (noble crayfish), and Pacifastacus leniusculus (signal crayfish). Growth indices reported included instantaneous growth rate (IGR), absolute growth rate (AGR), slope of log weight against time (GRE) and specific growth rate (SGR, IGR100). Studies were performed for varying time intervals under a wide range of stocking densities. Most reports did not express growth rate as an index but simply reported growth in terms of initial and final weights. The range of approaches used to express growth performance in freshwater crayfish growth studies hinders comparisons of growth rate and production findings. It is suggested that the reports of studies of growth performance in cultured crayfish include a growth rate parameter as well as initial and final weights. SGR is recommended as the parameter of choice since it is based on an exponential growth trend which is typically observed in measurements of weight increase with time in cultured juvenile and early adult crayfish.

The freshwater crayfish Cherax tenuimanus (marron) has been attracting an increasing degree of attention for aquaculture due to its high growth rate and large harvest size. In this study some important parameters related to the physiological energetics of C. tenuimanus were defined in a series of independent experiments. Food consumption by marron increased when fed a variety of foods, providing up to 29 joule/g dry wt crayfish per hour. Mean energy content of feces was 7, 941 joule/g dry wt representing up to 17% of ingested food while excreted energy was not important in the overall budget. Metabolic requirements per hour were 5.4 joule/g dry wt. Gross conversion efficiency was up to 58% for the experimental diets. This ability gives the species a marked advantage for commercial culture over other related species with more subdued growth efficiencies.

A plcistophorid microsporidian is described from marron, Cherax tenuimanus (Smith). The parasite is polysporous, forming eight, 16, 32 or 64 ovoid spores in persistent, two-layered mcrontogcnctic sporophorous vesicles. Nuclei remain isolated throughout merogony and sporogony. The sporophorous vesicle forms from the amorphous coat surrounding meronts, which thickens and condenses into two layers during sporogony. The parasite is placed in Vavraia Weiser, 1977, and named Vavraia parastacida sp. nov.

Blood samples collected in four Amerindian French Guiana populations (Palikur, Emerillon, Wayampi and Kali'na) in the early 1980s were screened for selected mtDNA and Y-chromosome length polymorphisms, and sequenced for the mtDNA hypervariable segment I (HVS-I). In addition, two other Amerindian populations (Apalaí and Matsiguenga) were examined for the same markers to establish the genetic relationships in the area. Strong dissimilarities were observed in the distribution of the founding Amerindian haplogroups, and significant p-values were obtained from F(ST) genetic distances. Interpopulation similarities occurred mainly due to geography. The Palikur did not show obvious genetic similarity to the Matsiguenga, who speak the same language and live in a region from where they could have migrated to French Guiana. The African-origin admixture observed in the Kali'na probably derives from historical contacts they had with the Bushinengue (Noir Marron), a group of escaped slaves who now lead independent lives in a nearby region. This analysis has identified significant clues about the Amerindian peopling of the North-East Amazonian region.

Juvenile Australian freshwater crayfish (Cherax tenuimanus) were individually housed in an experimental battery system and fed HFX CRD 84 and BML 81 S, two proposed standard reference diets for studies of crustacean nutrition. The HFX CRD 84 diet was accepted more readily than the BML 81 S diet. After 100 days, mean weight gain of marron fed the HFX CRD 84 diet was significantly greater than that of those fed the BML 81 S diet. Growth rate, measured 118 percent weight pin per ecdysis, declined during three successive 50 day periods. Growth on the proposed reference diets ranged from 16 to 33% of that achieved with pond raised marron of similar age. Both diets may be useful in the development of species specific modifications relative to nutrient composition.

Es werden die Eigenschaften dieser Pigmente, die vom hellen Orange bis zum dunkelsten Marron hergestellt werden konnen, besprochen. An Hand von Rontgenaufnahmen wird die wahrscheinliche Struktur diskutiert. Cadmium-Vermilion, a New Class of Pigments Properties of these pigments, varying from light orange till darkest marron, are described. In the light of radiograms, the most probable structure is discussed.