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This study reports on male-biased sex ratios in west Mediterranean populations of the freshwater anostracan Branchipus schaefferi (Crustacea, Anostraca, Branchipodidae), in contrast to populations elsewhere. Crossing experiments over several generations indicate a clear paternal inheritance of the trait, possibly with a dosage effect. Various mechanisms

The incorporation of active oxygen scavengers in polymer packaging materials is essential to allow packaging of oxidation sensitive products. Opposed to the currently available chemical oxygen scavengers, systems based upon natural and biological components could have advantages towards consumer perception and sustainability. A modelsystem for a new oxygen scavenging poly(ethylene terephthalate) (PET) bottle is proposed using an endospore-forming bacteria genus Bacillus amyloliquefaciens as the active ingredient. Spores were incorporated in poly(ethylene terephthalate, 1,4-cyclohexane dimethanol) (PETG), an amorphous PET copolymer having a considerable lower processing temperature and higher moisture absorption compared to PET. To asses spore viability after incorporation, a method was optimized to extract spores from PETG using a chloroform/water mixture. Samples were also analyzed using a Live/Dead BacLight Bacterial Viability kit. It was shown that endospores were able to survive incorporation in PETG at 210°C. Incorporated spores could actively consume oxygen for minimum 15 days, after an activation period of 1-2 days at 30°C under high humidity conditions. Industrial relevance: The study describes a modelsystem for the use of incorporated spores genus Bacillus amyloliquefaciens as an active oxygen scavenger in PET multilayer bottles using PETG as the middle layer material. Industrially, oxygen scavengers using incorporated viable spores as the active compound could have advantages towards consumer perception, recyclability, safety, material compatibility, production costs, … compared to currently available chemical oxygen scavengers.

Recently, the use of repellents for preventing the transmission of mosquito-borne diseases is getting increasingly more attention. However, most of the current repellents are volatile in nature and must be frequently re-applied as their efficacy is only limited to a short period of time. Therefore, a slow release and abrasion-resistant mechanism is needed for prolonging the protection time of the repellents. The focus of this study is on the direct micro-encapsulation of repellents from an emulsion and integration of already encapsulated repellents into nanofibres via electrospinning. Different repellents were electrospun in polyvinyl alcohol (PVA) nanofibrous structures, namely p -menthane-3,8-diol micro-capsules, permethrin, chilli and catnip oil. The repellents were successfully incorporated in the nanofibres and the tensile properties of the resulting samples did not have a significant change. This means that the newly created textiles were identical to current PVA nanofibrous textiles with the added benefit of being mosquito repellent. Principally, all incorporated repellents in the nanofibrous structures showed a significantly reduced number of mosquito landings compared to the control. Consequently, the currently described method resulted in a new and very effective repelling textile material that can be used in the prevention against mosquito-associated diseases.

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The combined effects of temperature and salinity on hatching performance of three anostracan species, Phallocryptus spinosa, Branchinecta orientalis and Streptocephalus torvicornis from East and West Azerbaijan, Iran, were studied. The cysts were kept for 10 days at seven different temperatures (12, 15, 18, 21, 24, 27 and 30°C) and four salinity conditions (0, 5, 10, and 15 gL) and the effects of the resulting 28 experimental conditions on hatching patterns (duration of pre-hatching period, hatching percentage at first day of hatching, cumulative hatching success) were examined. Results were tested by ANOVA and multiple regression was applied to generate contour models by polynomial equation. The hatching performance in all species was significantly affected by temperature and salinity. Based on contour plot analysis, maximum hatching for P. spinosa, B. orientalis and S. torvicornis cysts was registered at temperatures 19-25ºC, 18-23ºC and 16-20ºC, respectively, within the same salinity range of 0-1 gL–1 The highest cumulative hatching success among the species was observed in P. spinosa at the combination of 24°C and 0gL–1(88. 98%). No hatching was observed for eggs of S. torvicornis and B. orientalis incubated at lower (<15ºC) and higher (>27ºC) temperature, respectively. The pre-hatching period was prolonged with increase in salinity and decrease in temperature and was highest in P. spinosa (7.7 days at 12°C and 15 gL salinity). High hatching success was observed over wide ranges of temperature and salinity in P. spinosa eggs which demonstrates one of the possible mechanisms responsible for the wide distribution of this species

Organisms that tolerate essentially complete dehydration are said to be in anhydrobiosis, and can be referred to as anhydrobiotes. Those organisms are of great ecological and medical importance, but also provide models for the study of a variety of biological phenomena. We examined the tolerance of selected eukaryotic anhydrobiotes to high temperatures using slow (~4°C min -1 ) and rapid (~100°C min -1 ) heating to 110, 120, 130, and 140°C. Test organisms were then either returned to storage temperatures close to 22°C (preheating), or held at those high temperatures for an additional 10 min. Some anhydrobiotes survived slow heating to 130°C, whereas rapid heating led to a dramatic reduction in survival. None of these organisms encounter anywhere near these high temperatures in nature, so tolerance is not an obvious result of adaptation to current or recent conditions. We speculate that tolerance could have been achieved during the much earlier evolution of these organisms, and has been retained up to the present.

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