No evidence for visual context-dependency of olfactory learning in <Emphasis Type="Italic">Drosophila</Emphasis>

How is behaviour organised across sensory modalities? Specifically, we ask concerning the fruit fly Drosophila melanogaster how visual context affects olfactory learning and recall and whether information about visual context is getting integrated into olfactory memory. We find that changing visual context between training and test does not deteriorate olfactory memory scores, suggesting that these olfactory memories can drive behaviour despite a mismatch of visual context between training and test. Rather, both the establishment and the recall of olfactory memory are generally facilitated by light. In a follow-up experiment, we find no evidence for learning about combinations of odours and visual context as predictors for reinforcement even after explicit training in a so-called biconditional discrimination task. Thus, a ‘true’ interaction between visual and olfactory modalities is not evident; instead, light seems to influence olfactory learning and recall unspecifically, for example by altering motor activity, alertness or olfactory acuity.     

Sensitivity of Landsat‐Scale Energy Balance to Aerodynamic Variability in Mountains and Complex Terrain

The speed and direction of air flow through complex terrain are difficult to define. Both impact sensible and latent heat flux exchanges at the surface. Evapotranspiration (ET) models such as Mapping EvapoTranspiration at high Resolution with Internalized Calibration (METRIC?) estimate ET as a residual of the surface energy process and are thus sensitive to aerodynamics, including terrain‐induced impacts on roughness governing convective heat transfer (H). There is a need to explore the sensitivities of H estimation and thereby ET estimation to wind speed and terrain roughness in mountainous areas and to determine the merit of operating complex mesoscale wind field models in conjunction with the energy balance process. A sensitivity analysis is explored in METRIC where we increased wind speed in proportion to a relative elevation parameter and we increased aerodynamic roughness to assimilate impacts of relative terrain roughness, estimated in proportion to standard deviation of elevation within a 3 km locality. These aerodynamic modifications increased convective heat transfer in complex terrain and reduced estimated ET. In other sensitivity runs, we reduced estimated wind speed on estimated leeward slopes. Estimated ET with and without these sensitivity adjustments is shown for mountainous areas of Montana and Nevada. Changes in ET ranged from little change (<5%) for lower slopes to about 30% reductions on windward slopes and 25% increases on leeward slopes for some mid to high elevations in the Montana application.     

The Evaluation of Mesoporous Materials as Catalyst in Fast Pyrolysis of Wheat Straw

In this study, wheat straw was chosen as a biomass sample and the fast pyrolysis of this sample was carried out with or without catalyst at different conditions in a well-swept fixed-bed reactor. Experiments were carried out in a well-swept tubular fixed-bed reactor with a heating rate of 300°C/min, between pyrolysis temperature ranges 300–800°C in the nitrogen atmosphere. The results indicated that a maximum oil yield of 31.9% was obtained at a pyrolysis temperature of 500°C in non-catalytic procedure. Siliceous and Al-MCM-41 materials were evaluated as potential catalysts in the pyrolysis experiments. Mesoporous materials have large pore dimensions with strong acid sites. These acidic sites catalyze some reactions in pyrolysis. The product yields and the quality of bio-oil were influenced with using MCM-41 materials. The bio-oil yield was reduced, whereas the gas yield increased with using a catalyst in the experiments. An increase in the fractions of pure phenol, alkyl phenols, alkenes+alkanes, carbonyls, aromatic, and cyclic compounds and a decrease in the fractions of methoxy phenols, acids+esters, furans, and alcohols were observed in the presence of Al-MCM-41 material. According to all results, the use of Al-MCM-41 materials as catalyst in the pyrolysis can be suggested to obtain both quality fuels and valuable chemicals.     

Front velocity and structure of bottom gravity currents with a low volume of release propagating in a porous medium

The paper reports results of large eddy simulations of lock exchange compositional gravity currents with a low volume of release advancing in a horizontal, long channel. The channel contains an array of spanwise-oriented square cylinders. The cylinders are uniformly distributed within the whole channel. The flow past the individual cylinders is resolved by the numerical simulation. The paper discusses how the structure and evolution of the current change with the main geometrical parameters of the flow (e.g., solid volume fraction, ratio between the initial height of the region containing lock fluid and the channel depth, ratio between the initial length and height of the region containing lock fluid) and the Reynolds number. Though in all cases with a sufficiently large solid volume fraction the current transitions to a drag-dominated regime, the value of the power law coefficient, α, describing the front position’s variation with time (x _f  ~ t ^α , where t is the time measured from the removal of the lock gate) is different between full depth cases and partial depth cases. The paper also discusses how large eddy simulation (LES) results compare with findings based on shallow-water equations. In particular, LES results show that the values of α are not always equal to values predicted by shallow water theory for the limiting cases where the current height is comparable, or much smaller, than the channel depth.     

Biochemical response to exposure to six textile dyes in early developmental stages of Xenopus laevis

The present study was undertaken to determine the toxic effect of a lethal concentration of six different commercially used textile dyes on the 46th stage of Xenopus laevis tadpoles. The tadpoles were exposed to Astrazon Red FBL, Astrazon Blue FGRL, Remazol Red RR, Remazol Turquoise Blue G-A, Cibacron Red FN-3G, and Cibacron Blue FN-R for 168 h in static test conditions, and thus, 168-h median lethal concentrations (LC₅₀s) of each dye were determined to be 0.35, 0.13, 112, 7, 359, and 15.8 mg/L, respectively. Also, to evaluate the sublethal effects of each dye, tadpoles were exposed to different concentrations of dyes (with respect to 168-h LC₅₀s) for 24 h. The alteration of selected enzyme activities was tested. For this aim, glutathione S-transferase (GST), carboxylesterase, and lactate dehydrogenase (LDH) were assayed. After dye exposure, the GST induction or inhibition and LDH induction indicated some possible mechanisms of oxidative stress and deterioration in aerobic respiration processes induced by the tested dyes. Findings of the study suggest that selected biomarker enzymes are useful in understanding the toxic mechanisms of these dyes in X. laevis tadpoles as early warning indicators. Therefore, these selected biomarkers may evaluate the effect of environmental factors, such as textile dye effluents and other industrial pollutants, on amphibians in biomonitoring studies.     

Evaluation of physical, chemical and microbiological properties of lake Uluabat, Turkey

Lake Uluabat, known for its scenic beauty and richness of aquatic life, is situated in Marmara Region, Bursa (Turkey). On account of its importance, lake Uluabat was designated by the Ministry of Environment as a Ramsar site in 1998. Physical, chemical and microbiological parameters of the aquatic ecosystem in lake Uluabat were measured monthly at five stations from February 2003 to January 2004. The results showed that lake Uluabat can be classified as Class I with respect to temperature (16.36 +/- 7.47 degrees C), nitrate nitrogen (0.63 +/- 0.50 mgl(-1)), sodium (9.64 +/- 2.78 mgl(-1)), chloride (20.45 +/- 4.59 mgl(-1)), sulphate (54.80 +/- 29.97 mgl(-1)); as Class II with respect to dissolved oxygen (7.62 +/- 1.99 mgl(-1)), ammonium nitrogen (0.52 +/- 0.49 mgl(-1)), chemical oxygen demand (35.74 +/- 10.66 mgl(-1)), total coliform (2027 MPN100 ml(-1) (average value)); as Class III with respect to pH (8.69 +/- 0.16) and as Class IV with respect to total nitrogen (84.94 +/- 66.13 mgl(-1)), total phosphorus (1.11 +/- 3.01 mgl(-1)), biochemical oxygen demand (21.21 +/- 6.60 mgl(-1)) according to TWPCR (Turkey Water Pollution Control Regulation). The nutrient content of lake waterapparently indicated that lake had an eutrophic characteristic. Phosphorus was determined as a limiting factor in lake. The measured hardness values (140.94 +/- 14.61 CaCO3 mgl(-1)) indicated that lake water was classified as soft/hard during the study period. Eutrophic characteristic of the lake and contaminant accumulation in water will probably affect the future use of the lake. Therefore, pollution parameters must be regularly monitored and evaluated according to aquatic living and local regulations.