Effect of surfactants on Fenton's reagent-mediated degradation of Kraft black liquor

One of the limitations of the biodegradation of hydrophobic chemical compounds, like lignins, is their low solubility in the aqueous solution where this process takes place. To resolve this problem, surfactants have been used to improve the solubility of these hydrophobic compounds. In this investigation, we studied the effect of surfactants (anionic, cationic, and non-ionic) on the treatment of Kraft black liquor with Fenton's reagent. In the Fenton reaction, H2O2 (two different concentrations, 10 mM and 20 mM), FeCl2 (1 mM) and surfactant solution (10%) were used. Black liquor degradation was determined by UV/Visible spectrophotometry and by measuring phenolic groups. In the presence of Fenton's reagent, the optimum conditions for the oxidative degradation of black liquor were 10 mM H2O2, 1 microL of 10% solution of anionic surfactant (SDS). The importance of the use of surfactants for preparing black liquor for subsequent Fenton's reagent-mediated degradation was discussed.     

Benefits of protected areas for nonbreeding waterbirds adjusting their distributions under climate warming

Climate warming is driving changes in species distributions and community composition. Many species have a so-called climatic debt, that is, shifts in range lag behind shifts in temperature isoclines. Inside protected areas (PAs), community changes in response to climate warming can be facilitated by greater colonization rates by warm-dwelling species, but also mitigated by lowering extirpation rates of cold-dwelling species. An evaluation of the relative importance of colonization-extirpation processes is important to inform conservation strategies that aim for both climate debt reduction and species conservation. We assessed the colonization-extirpation dynamics involved in community changes in response to climate inside and outside PAs. To do so, we used 25 years of occurrence data of nonbreeding waterbirds in the western Palearctic (97 species, 7071 sites, 39 countries, 1993–2017). We used a community temperature index (CTI) framework based on species thermal affinities to investigate species turnover induced by temperature increase. We determined whether thermal community adjustment was associated with colonization by warm-dwelling species or extirpation of cold-dwelling species by modeling change in standard deviation of the CTI (CTI_SD). Using linear mixed-effects models, we investigated whether communities in PAs had lower climatic debt and different patterns of community change than communities outside PAs. For CTI and CTI_SD combined, communities inside PAs had more species, higher colonization, lower extirpation, and lower climatic debt (16%) than communities outside PAs. Thus, our results suggest that PAs facilitate 2 independent processes that shape community dynamics and maintain biodiversity. The community adjustment was, however, not sufficiently fast to keep pace with the large temperature increases in the central and northeastern western Palearctic. Our results underline the potential of combining CTI and CTI_SD metrics to improve understanding of the colonization-extirpation patterns driven by climate warming.     

Functional responses of copepod nauplii using a high efficiency gut fluorescence technique

To investigate copepod nauplii ingestion rates on phytoplankton, we have adapted the traditional gut fluorescence technique as it can be used with lower gut pigment concentrations. With the improved technique, laboratory experiments were performed to estimate functional responses for nauplii of Calanus helgolandicus and Centropages typicus. Nauplii were raised from eggs to copepodites and the experiments were performed with stages NIV-NV. Gut evacuation rates and ingestion rates were measured on Isochrysis galbana at different concentrations. Specific ingestion rates ranged between 0.038–0.244 μg C μg⁻¹ nauplii C d⁻¹ for C. typicus and 0.041–1.412 μg C μg⁻¹ nauplii C d⁻¹ for C. helgolandicus. Both species showed a type III functional response, reaching a saturation concentration at around 600 μgC l⁻¹ for C. typicus and 800 μgC l⁻¹ for C. helgolandicus. An erratum to this article can be found at     

Cellular dynamics of in vitro allogeneic reactions of<Emphasis Type="Italic"> Hymeniacidon heliophila</Emphasis> (Demospongiae: Halichondrida)

Allograft reactions of the sponge Hymeniacidon heliophila Parker, 1910 have been studied and quantified at the cellular level in vitro. Cell-layer assays were used to record the timing of rejection between allogeneic individuals and to investigate changes in the cellular subpopulations of primmorphs belonging to different individuals and placed in direct contact. The initial contact on both cell layers and primmorphs was followed by partial fusion and ended by their isolation with formation of a defined barrier but without marked collagen deposition. Using cytospins, cellular subpopulations from primmorphs were morphologically distinguished based on overall shape and on nuclear and cytoplasmic characteristics. In the beginning of the cultures up to 17 cell types could be recognized. Within 5 days, following reaggregation and primmorph formation, populations of eight of these types suffered marked reduction, whereas nine other cell types were either maintained or reduced at a slower pace. When submitted to allogeneic contact, the cellular dynamics of the four remaining types were altered. Surprisingly, the percentage of archeocytes is reduced, probably depleted by differentiation into other, differentiated cell populations. Cellular responses to allogeneic contact were characterized mainly by a transient increase in globoferous cells, a larger participation of presumed collagen-secreting cells, and by a remarkable expansion of the collencyte population. The collencyte population remained altered after the isolation of the individuals by a collagen barrier, and this can represent a mechanism of short-term immune memory.Communicated by O. Kinne, Oldendorf/Luhe     

Cave molly females (Poecilia mexicana, Poeciliidae, Teleostei) like well-fed males

We examined the preference of Atlantic molly females (Poecilia mexicana) to associate with a well-fed or a starved male in simultaneous choice tests. Females from three different populations were tested in three treatments: (1) the females could choose on the basis of multiple cues from the males (visual plus non-visual); (2) only non-visual cues could be perceived in darkness, (3) only visual cues were presented. The three tested populations differ clearly in their ecology: one population occurs in a typical river habitat, the second one in a milky sulfur creek outside a cave, and the third population occurs in a cave habitat (cave molly). In the river-dwelling population, females never showed a preference. In the population from the sulfur creek, females preferred to associate with the well-nourished male when visual cues from the males were available. Only cave molly females exhibited a strong preference for well-nourished males in all treatments. A morphological comparison demonstrated that wild-caught males from river habitats are typically in a good nutritional state. In the sulfur creek, males showed signs of starvation. Cave molly males were in an even worse nutritional state. In the cave population, saturated males probably indicate high fitness, thereby driving the evolution of the preference for good male nutritional state.Communicated by K. Lindström     

Absolute configuration of the major sex pheromone component of the satin moth, Leucoma salicis, verified by field trapping test in Hungary

Summary. Male satin moths, Leucoma (Stilpnotia) salicis L. (Lepidoptera, Lymantriidae) were attracted only to (3Z,6R,7S,9R,10S)-isomer out of the four (3Z)-cis-6,7-cis-9,10-diepoxy-3-henicosenes (leucomalure). This was demonstrated by field trapping test with a bivoltine population in a mixed poplar-willow forest along the flood area of the river Danube at Adony, Hungary.     

Maternal quality and differences in milk production and composition for male and female Iberian red deer calves (Cervus elaphus hispanicus)

Several theories predict a sex-biased investment either through unbalanced sex ratios in offspring or through differences in provisioning. According to them, one would expect an optimisation in indirect fitness, or else a compensation for increased mortality of one sex. In addition, biases in provisioning may also arise as a consequence of weight-dependent non-adaptive nutrient demands by offspring. This study examines milk provisioning and sex biases in offspring sex ratio together with maternal quality variables. Mothers of higher quality (weight and age) showed greater milk provisioning ability (in terms of production) resulting in greater calf weight gain. Mothers of sons produced greater yields of milk, milk protein, fat and lactose than mothers of daughters, and increased percentage of protein after controlling for higher male birth weight. In contrast, mothers of males did not differ from mothers of females in age or any body weight variables related to maternal quality. These results suggest that differences in milk production and composition for sons and daughters are rather a mechanism to optimise indirect fitness than a mechanism to compensate for increased mortality in male calves, or a consequence of greater weight-dependent nutrient demands by heavier male calves. Results also suggest that biases in milk provisioning may occur without biases in offspring sex ratio, and furthermore, in contrast to the prediction that biases should be relative to the mean investment of the population, that milk provisioning biases might not be relative.Communicated by F. Trillmich     

In vitro toxicity of selected pesticides on RTG-2 and RTL-W1 fish cell lines

The rainbow trout fish cell lines RTG-2 and RTL-W1 were used to determine the cytotoxic effects of the pesticides bifenthrin, cypermethrin, cyhalothrin, lambda-cyhalothrin, quinalphos and chlorpyrifos. Cytotoxicity was measured by EROD and beta-Gal enzymatic activities, the neutral red (NR) uptake assay, and the FRAME KB protein (KBP) assay. The beta-Gal activity was unaffected by the pesticide exposure. The EROD activity was induced by cyhalothrin and lambda-cyhalothrin (RTG-2 and RTL-W1) and by bifenthrin (RTL-W1). Dose dependent inhibition responses were observed for EROD activity in cells exposed to quinalphos (RTL-W1) and chlorpyrifos (RTG-2 and RTL-W1). RTL-W1 offered a better response for EROD induction. The EC50 values on EROD endpoint were more sensitive than NR and KBP. The acute fish toxicity of chlorpyrifos and quinalphos depends highly on the species; the species sensitivity distributions cover several orders of magnitude and the values obtained for EROS were within the lowest part of the reported ranges.