Variation in wood volatile compounds in a mixed oak stand: strong species and spatial differentiation in whisky-lactone content

The effect of species and ecological conditions on oak volatile extractive content was investigated in an evenaged (100 years) stand located in western France. The sample included a total of 286 trees (118 sessile, 158 pedunculate and 10 oaks with an intermediate morphology) growing in contrasted environments (plateau, intermediate slope, small valley). The main factor influencing oak extractives level is species. The effect of the local environment appears negligible. No correlation between ring width and volatile extractive content was found. Q. petraea is significantly richer than Q. robur in eugenol and whisky-lactone (10.8 vs. 0.6 μg/g). However, two groups of sessile oaks could be identified, one poor and one rich in whisky-lactone. Among the latter, either the cis or the trans stereoisomer was predominant, suggesting that their production is not independent. A strong spatial structure was detected for whisky-lactone (cis-, trans- and total whisky-lactone, for the two species combined but also for Q. petraea alone in the case of the cis isomer).     

CLINICAL VALUE OF FRUCTOSAMINE MEASUREMENTS AND FRUCTOSAMINE-ALBUMIN RATIO IN HYPOGLYCEMIC FERRETS (MUSTELA PUTORIUS FURO)

The objective of this preliminary study was to establish a reference range for plasma fructosamine concentration and fructosamine-albumin ratio in healthy ferrets and to compare these reference intervals to values obtained from hypoglycemic ferrets. Fructosamine concentration has been shown to reflect blood glucose concentration over the previous 1 to 2 weeks in other animal species, and may be a useful indicator of chronic hypoglycemia in ferrets diagnosed with insulinoma. Plasma fructosamine was measured with an automated colorimetric assay using nitroblue tetrazolium. Thirty-two clinically healthy and 5 hypoglycemic ferrets were included in the study. The reference interval in healthy ferrets for fructosamine was 110 (98 to 123) – 203 (191 to 218) μmol/L, and the reference interval for plasma fructosamine-albumin ratio was 5.1 (4.6 to 5.6) – 8.6 (8.2 to 9.0) μmol/g. Results for hypoglycemic ferrets were within the ranges for both fructosamine and fructosamine-albumin ratio. As there were no significant differences between the healthy and hypoglycemic ferrets, this study suggests that fructosamine concentration and fructosamine-albumin ratio are not likely to be useful in determining insulinoma-associated chronic hypoglycemia in ferrets.     

Policy and transparency gaps for oceanic shark and rays in high seas tuna fisheries

The incidental capture by marine fisheries as bycatch poses a global threat to pelagic sharks and rays. In large, industrialized fisheries that often operate in areas beyond national jurisdiction, at least 22 threatened species of pelagic elasmobranchs are caught as bycatch, representing the majority of megafauna bycatch in tuna fisheries. Here, we investigate (1) the efficacy of the current policies of the five tuna-related Regional Fisheries Management Organizations (tRFMOs) in mitigating elasmobranch bycatch, (2) data needed to better assess the amount and impact of elasmobranch bycatch and (3) the research necessary for the adoption of new policies. We found that tRFMOs have adopted 34 active policies that address pelagic elasmobranch bycatch. However, most policies (~76%, n = 26) are unlikely to avoid or minimize elasmobranch bycatch. Instead, most policies focus on mitigating post-capture mortality via remediation and requiring or encouraging research and data collection. Despite the emphasis on research mandates, we find that the existence of research was not related to policy adoption, suggesting that lack of research has not historically prohibited policymaking. Overall, we suggest that current research and data transparency, though perhaps not necessary for policy adoption, are not sufficient to adequately evaluate the population-level impacts of bycatch on many elasmobranch species in tRFMO-managed fisheries. Given these results, we recommend a precautionary approach that involves reforms in tRFMO voting processes to facilitate the adoption of binding requirements for elasmobranch catch limits, bycatch avoidance, pre- and post-capture handling and release modifications and protection of areas important to threatened pelagic elasmobranchs.     

Improved characterization of the botanical origin of sugar by carbon-13 SNIF-NMR applied to ethanol

Until now, no analytical method, not even isotopic ones, had been able to differentiate between sugars coming from C4-metabolism plants (cane, maize, etc.) and some crassulacean acid metabolism plants (e.g., pineapple, agave) because in both cases the isotope distributions of the overall carbon-13/carbon-12 and site-specific deuterium/hydrogen isotope ratios are very similar. Following recent advances in the field of quantitative isotopic carbon-13 NMR measurements, a procedure for the analysis of the positional carbon-13/carbon-12 isotope ratios of ethanol derived from the sugars of pineapples and agave using the site-specific natural isotopic fractionation-nuclear magnetic resonance (SNIF-NMR) method is presented. It is shown that reproducible results can be obtained when appropriate analytical conditions are used. When applied to pineapple juice, this new method demonstrates a unique ability to detect cane and maize sugar, which are major potential adulterants, with a detection limit in the order of 15% of the total sugars, which provides an efficient mean of controlling the authenticity of juices made from this specific fruit. When applied to tequila products, this new method demonstrates a unique ability to unambiguously differentiate authentic 100% agave tequila, as well as misto tequila (made from at least 51% agave), from products made from a larger proportion of cane or maize sugar and therefore not complying with the legal definition of tequila.     

Antioxidant Activity of Phenolics Compounds From Sugar Cane (Saccharum officinarum L.) Juice

Phenolic compounds in sugar cane (Saccharum officinarum L.) juice were identified and quantified by analytical high performance liquid chromatography and photodiode array detection, showing the predominance of flavones (apigenin, luteolin and tricin derivatives), among flavonoids, and of hydroxycinnamic, caffeic and sinapic acids, among phenolic acids, representing a total content of around 160 mg/L. A tricin derivative was present in the highest proportion (>10% of the total). The phenolic extract obtained from sugar cane juice showed a protective effect against in vivo MeHgCl intoxication and potent inhibition of ex vivo lipoperoxidation of rat brain homogenates, indicating a potential use for beneficial health effects and/or therapeutic applications.     

Wind loading of trees: influence of tree size and competition

Wind damage to forests is an important ecological disturbance factor. At the same time, it can have serious economic consequences due to a reduction in timber production. Current models for predicting the risk of wind damage are useful, but generally only focus on the “mean” tree within uniform stands. This paper presents measurements made of wind loading on trees of different sizes within four forest stands of different structure and management history, but all well-acclimated to current wind conditions. Each tree demonstrated a linear relationship between the maximum hourly turning moment and the square of the average hourly wind speed at the canopy top; we defined this ratio (the gradient of the line M _max vs. u ²) as the turning moment coefficient (T _C). T _C was correlated with tree size, in a relationship that differed little between the four forest sites despite the differences between the stands. The relationship between T _C and individual tree competition within each stand was investigated, using both distance-independent and distance-dependent competition indices. All sites showed decreasing T _C with increasing competition. However, the relationships differed between sites and would also be expected to change through time for a single site. The distance-dependent indices offered no improvement over the simpler, non-spatial indices that required only a diameter distribution. We suggest how, subject to further work, the results presented could be applied to calculate the risk of wind damage to trees of different sizes within a forest stand, and how the risk of wind damage to individual trees might change in response to thinning.     

Assessment of three strategies practiced by fishery managers for restoring native brown trout (Salmo trutta) populations in Northern French Alpine Streams

Abstract – The efficiency of three strategies carried out by fisheries managers to restore native Mediterranean brown trout populations threatened by non‐native Atlantic populations were assessed. The strategies tested were (i) genetic refuge area where stocking is banned, (ii) stocking with Mediterranean fry and (iii) translocation of wild Mediterranean spawners. Using two discriminatory microsatellite loci between Atlantic and Mediterranean alleles, we compared the genetic composition of samples before and after the changes of practices. The three strategies had several detectable effects in the standing populations causing strong temporal changes in departures from Hardy–Weinberg equilibrium and linkage equilibrium between loci and the apparition of new Mediterranean alleles. The significant reductions in the proportions of Atlantic alleles observed over time can mostly be explained by the disappearing of the pure non‐native Atlantic trout after the stopping of hatchery releases. The results, however, also suggest that the active strategies carried out by managers led to intraspecific introgression between both non‐native Atlantic and native Mediterranean strains.     

A synthetic conjugate polysaccharide vaccine against Haemophilus influenzae type b

Glycoconjugate vaccines provide effective prophylaxis against bacterial infections. To date, however, no commercial vaccine has been available in which the key carbohydrate antigens are produced synthetically. We describe the large-scale synthesis, pharmaceutical development, and clinical evaluation of a conjugate vaccine composed of a synthetic capsular polysaccharide antigen of Haemophilus influenzae type b (Hib). The vaccine was evaluated in clinical trials in Cuba and showed long-term protective antibody titers that compared favorably to licensed products prepared with the Hib polysaccharide extracted from bacteria. This demonstrates that access to synthetic complex carbohydrate-based vaccines is feasible and provides a basis for further development of similar approaches for other human pathogens.