Spatial–temporal variability of epibenthic assemblages on subtidal biogenic reefs in the northern Adriatic Sea

Spatial distribution and temporal variation of epibenthic assemblages of coralligenous biogenic rocky outcrops occurring in the northern Adriatic Sea (45°04′–45°24′N; 12°23′–12°43′E) were investigated by photographic sampling from 2003 to 2006 at 12 randomly selected sites. The dominant reef-forming organisms were the encrusting calcareous algae (Lithophyllum stictaeforme, Lithothamnion minervae and Peyssonnelia polymorpha), while the main bioeroders were boring sponges (Cliona viridis, C. celata, C. thoosina, C. rhodensis, Piona vastifica) and the bivalve Gastrochaena dubia. Composition of the assemblages varied thorough years and among sites. Spatial heterogeneity, at local and regional scale, prevailed over temporal variation. This variability was related both to the geo-morphological features of the outcrops and to environmental variables. Sites clearly differed in the percent cover of reef builder and bioeroder species while only limited temporal variation within site was found. Some taxa revealed complex intra-site temporal trends. These results provide valuable information on the diversity and variability of epibenthic assemblages of the northern Adriatic coralligenous reefs, essential for the management and conservation of these unique biogenic habitats.     

Factors determining the hatching success of Antarctic krill <Emphasis Type="Italic">Euphausia superba</Emphasis> embryo: lipid and fatty acid composition

The present study addresses the effect of maternal diet on hatching success and condition of embryos and larvae of Antarctic krill Euphausia superba. Lipid and fatty acid content and composition were determined in field and laboratory samples. Developmental stages analyzed in embryos included: multiple-cell, gastrula, and limb-bud stages. Larval stages analyzed included: nauplius I, nauplius II, and metanauplius. Laboratory-reared embryos were spawned by gravid females incubated under three feeding groups: (1) phytoplankton mixture, (2) phytoplankton mixture and minced clam, and (3) phytoplankton mixture, minced clam, and commercial larval food. Hatching success was highest in group 3 (100%), lowest in group 1 (0%), and highly variable in field samples (0–48%). Lipid decreased slightly in embryos during embryonic development, while large decreases in lipid were found during nauplius development. High levels of 18:2(n-6), 20:4(n-6), and 22:6(n-3) observed with group 3 samples coincided with high hatching success in krill embryos. The ratio of 22:6(n-3)/20:5(n-3) also correlated to hatching success of embryos. The fatty acid profile of embryos in group 3 was similar to that of the field-collected embryos, reflecting the contribution of the commercial larval food in the maternal diet. In our study, the maternal diet was found to influence the fatty acid composition of embryos and in turn affects the hatching success of krill. Specific polyunsaturated fatty acids appeared to play important roles in embryogenesis in krill.     

Absorption characteristics of potassium carbonate-based solutions with rate promoters and corrosion inhibitors

In this research, absorbents for CO₂ capture were prepared by blending 30 wt% potassium carbonate, 3 wt% of a rate promoter, and 1 wt% of a corrosion inhibitor. Pipecolic acid, sarcosine, and diethanolamine were chosen as rate promoter candidates. Based on a rate promoter screening test for CO₂ loading capacity and absorption rate, pipecolic acid and sarcosine were selected to be used as rate promoters. 1,2,3-benzotriazole and ammonium thiocyanate were chosen as corrosion inhibitors, and they were mixed with a 30 wt% potassium carbonate-based absorbent mixture containing one of the rate promoters. The absorption rates for four absorbent solutions (30 wt% potassium carbonate?+?3 wt% pipecolic acid?+?1 wt% 1,2,3-benzotriazole, 30 wt% potassium carbonate?+?3 wt% pipecolic acid?+?1 wt% ammonium thiocyanate, 30 wt% potassium carbonate?+?3 wt% sarcosine?+?1 wt% 1,2,3-benzotriazole, and 30 wt% potassium carbonate?+?3 wt% sarcosine?+?1 wt% ammonium thiocyanate) were measured, tabulated, and graphically displayed. These types of absorbents can be used for capturing CO₂ under high temperature and pressure conditions, such as those found in coal-fired power plants.     

Ethoxylated Soybean Polyols for Polyurethanes

Soybean polyols prepared by ring opening reactions of epoxidized soybean oil with hydrogen active compounds (water, alcohols, organic or inorganic acids, thiols, hydrogen etc.) have a low reactivity in the reaction with isocyanates because the hydroxyl groups are secondary. This paper presents a simple and convenient method to increase the reactivity of soybean polyols with secondary hydroxyl groups by ethoxylation reactions with the preservation of triglyceride ester bonds. The method uses mild reaction conditions: low alkoxylation temperature of 35–45 °C, low pressure of 0.1–0.2 MPa (15–30 p.s.i.) and a superacid as catalyst (HBF₄). The new soybean polyols have a higher reactivity toward isocyanates in polyurethane formation due to the high percentage of primary hydroxyl groups. The primary hydroxyl content was determined by the second order kinetics of polyol reaction with phenyl isocyanate.     

The Properties of Poly(<Emphasis Type="SmallCaps">l</Emphasis>-Lactide) Prepared by Different Synthesis Procedure

Different synthesis methods were applied to determine optimal conditions for polymerization of (3S)-cis-3,6-dimethyl-1,4-dioxane-2,5-dione (l-lactide), in order to obtain poly(l-lactide) (PLLA). Bulk polymerizations (in vacuum sealed vessel, high pressure reactor and in microwave field) were performed with tin(II) 2-ethylhexanoate as the initiator. Synthesis in the vacuum sealed vessel was carried out at the temperature of 150 °C. To reduce the reaction time second polymerization process was carried out in the high pressure reactor at 100 °C and at the pressure of 138 kPa. The third type of rapid synthesis was done in the microwave reactor at 100 °C, using frequency of 2.45 GHz and power of 150 W at the temperature of 100 °C. The temperature in this method was controlled via infrared system for in-bulk measuring. The solution polymerization (with trifluoromethanesulfonic acid as initiator) was possible even at the temperature of 40 °C, yielding PLLA with narrow molecular weight distribution in a very short period of time (less than 6 h). The obtained polymers had the number-average molecular weights ranging from 43,000 to 178,000 g mol⁻¹ (polydispersity index ranging from 1 to 3) according to the gel permeation chromatography measurements. The polymer structure was characterized by Fourier transform infrared and NMR spectroscopy. Thermal properties of the obtained polymers were investigated using thermogravimetry and differential scanning calorimetry.     

Climate change and variability in Sub-Saharan Africa: a review of current and future trends and impacts on agriculture and food security

Sub-Saharan Africa has been portrayed as the most vulnerable region to the impacts of global climate change because of its reliance on agriculture which is highly sensitive to weather and climate variables such as temperature, precipitation, and light and extreme events and low capacity for adaptation. This article reviews evidence on the scope and nature of the climate change challenge; and assesses the impact of climate change on agriculture and food security in Sub-Saharan Africa. From the review, it is apparent that the climate in Africa is already exhibiting significant changes, evident by changes in average temperature, change in amount of rainfall and patterns and the prevalence of frequency and intensity of weather extremes. The review also revealed that although uncertainties exist with regards to the magnitude of impacts, climate will negatively affect agricultural production in Sub-Saharan Africa. Specifically, as result of current and expected climate change, the area suitable for agriculture, the length of growing seasons and yield potential, particularly along the margins of semi-arid and arid areas, are expected to decrease. These impacts will affect all components of food security: food availability, food accessibility, food utilisation and food stability and hence increase the risk of hunger in the region. The review thus confirms the general consensus that Sub-Saharan Africa is the most vulnerable region to climate change. It suggests that, policymakers and development agencies should focus on formulating and implementing policies and programmes that promote farm level adaptation strategies currently being practiced by farmers across the region.     

An integrated assessment of climate change impacts for Greece in the near future

Climate changes in the Mediterranean region, related to a significant increase in temperature and changes in precipitation patterns, can potentially affect local economies. Agriculture and tourism are undoubtedly the most important economic sources for Greece and these may be more strongly affected by changing future climate conditions. Climate change and their various negative impacts on human life are also detected in their environment; hence this study deals with implications, caused by changing climate, in urban and forest areas. Potential changes for the mid-twenty-first century (2021–2050) are analysed using a high-resolution regional climate model. This paper presents relevant climatic indices, indicative for potential implications which may jeopardise vital economic/environmental sectors of the country. The results provide insights into particular regions of the Greek territory that may undergo substantial impacts due to climate change. It is concluded that the duration of dry days is expected to increase in most of the studied agricultural regions. Winter precipitation generally decreases, whereas an increase in autumn precipitation is projected in most areas. Changing climate conditions associated with increased minimum temperatures (approximately 1.3°C) and decreased winter precipitation by 15% on average suggest that the risk for forest fires is intensified in the future. In urban areas, unpleasantly high temperatures during day and night will increase the feeling of discomfort in the citizens, while flash floods events are expected to occur more frequently. Another impact of climate change in urban regions is the increasing energy demand for cooling in summer. Finally, it was found that continental tourist areas of the Greek mainland will more often face heatwave episodes. In coastal regions, increased temperatures especially at night in combination with high levels of relative humidity can lead to conditions that are nothing less than uncomfortable for foreigners and the local population. In general, projected changes associated with temperature have a higher degree of confidence than those associated with precipitation.     

Effects of NO,NO<Subscript>2</Subscript>, CO and SO<Subscript>2</Subscript> on NO oxidation over Pt/TiO<Subscript>2</Subscript> for hybrid fast SCR process

The selective catalytic reduction (SCR) rate of NO with N-containing reducing agents can be enhanced considerably by converting part of NO into NO₂. The enhanced reaction rate is more pronounced even at lower temperatures by using an equimolar mixture of NO and NO₂ (fast SCR reaction). The oxidation characteristics of NO over catalyst Pt/TiO₂ have been determined in a fixed bed reactor (8 mm-ID) with different concentrations of oxygen, nitric oxide and nitrogen dioxide in the presence of 8% water. The conversion of NO to NO₂ increases with increasing oxygen (O₂) concentration from 3 to 12%, but it levels off at higher O₂ concentrations. The NO conversion to NO₂ decreases with increasing NO concentration and it also decreases by an addition of NO₂ in the feed stream. Therefore, the oxidation of NO over Pt/TiO₂ catalyst could be auto-inhibited by the reaction product of NO₂. The effects of CO and SO₂ on NO oxidation characteristics have also been determined. In fact, the presence of SO₂ significantly suppresses oxidation of NO but due to the less stability of sulfate on anatase structure in TiO₂, it becomes less significant. On the other hand, the presence of CO increases NO oxidation significantly due to the auto-inhibition effect by CO. Moreover, the effect of SO₂/CO on NO oxidation has also been determined and it was observed that NO oxidation decreases with the increase in SO₂/CO ratio.     

Who Loves Mosquitoes? Care Ethics,Theory of Obligation and Endangered Species

The focus of this paper is on normative ethical theories and endangered species. To be exact, I examine two theories: the theory of obligation and care ethics, and ask which is better-suited in the case of endangered species. I argue that the aretic, feminist-inspired ethics of care is well-suited in the case of companion animals, but ill-suited in the case of endangered species, especially in the case of “unlovable” species. My argument presupposes that (1) we now live an era where human disturbances to planetary ecosystems are triggering a sixth mass species extinction, and (2) widespread interventions will be needed to save many species from extinction.