Effect of microencapsulation on survival of Lactobacillus plantarum in simulated gastrointestinal conditions, refrigeration, and yogurt

In the present research the survival of free and microencapsulated cells of a new strain of Lactobacillus plantarum BL011 under stress conditions was tested in sodium alginate or pectin, coated with sodium alginate or chitosan. Results for the simulated gastrointestinal medium (SGT) showed no change in viability of cells in relation to the control. However, the simulated gastric medium (GM) drastically reduced the viability under the tested conditions, with no significant differences between free and immobilized cells. Under refrigerated storage viability of immobilized cells were greatly enhanced compared to the free microorganisms, and the treatments showing the lowest loss of viability were those of 4% (w/v) pectin, 3% (w/v) sodium alginate coated with chitosan and a mixture of 2% (w/v) sodium alginate and 2% (w/v) pectin, respectively. Loss of viability of immobilized L. plantarum in 3% alginate coated with chitosan in yogurt was of 0.55 log cycles during 38 days of storage. The results of this study suggest the efficiency of immobilization techniques to increase the survival of lactobacilli in yogurt under refrigerated storage.     

Regularity of rotational travelling water waves

Several recent results on the regularity of streamlines beneath a rotational travelling wave, along with the wave profile itself, will be discussed. The survey includes the classical water wave problem in both finite and infinite depth, capillary waves and solitary waves as well. A common assumption in all models to be discussed is the absence of stagnation points.     

Microstructural Evolution and Mechanical Behaviour of Metastable Cu-Zr-Co Alloys

Three different Cu-Zr-Co alloys, namely Cu40Zr37.5Co22.5, Cu42.5Zr45Co12.5 and Cu49Zr49Co2, were obtained by rapid cooling. The microstructure and phase formation of as-cast rods with diameters of 2 mm are compared with those of the respective ingots. An increasing Co content stabilises the B2 CuZr phase and leads to the precipitation of a ternary Cu-Zr-Co phase. The variation of the cooling rate affects the size of the B2 dendrites as well as the volume fraction and the morphology of the interdendritic phases. The mechanical properties were determined in compression and all alloys show a certain plastic deformability despite the presence of several binary and ternary intermetallic phases. The deformation mechanisms are discussed on the basis of the microstructures and the constituent phases.     

The case for solar/hydrogen energy

Since sustainable, technologically-converted solar energy is the likely basis for our post-fossil-energy future, there is a basic need for solar-produced fuels. It is noteworthy that heat and electricity, solely, are being developed as solar-energy delivery means, while historically civilizations depend on fuels. Hydrogen, a clean, efficiently-used fuel, can be readily derived from water using any of a number of both proved and prospective solar-energy conversion technologies—both direct and indirect (hydropower, wind, etc.). Solar/hydrogen (and oxygen) can also extend depleting fossil-energy resources while ameliorating environmental degradation. The Hydrogen Energy System concept is overviewed as background.A recent ‘Solar/Hydrogen Systems Assessment’ delineated early-availability systems based on photovoltaic, thermal/heat-engine, wind and hydropower solar conversion, and associated water electrolysis to yield product hydrogen and oxygen as ‘hydrogen energy’. Involved technologies being highly modular, good economics of equipment manufacture and deployment are inherent, as is early availability and as-needed rates of construction (in contrast, e.g., with nuclear-plant experience). Proved technological means exist for transporting, storing and distributing hydrogen energy to end-users.Most significant, both small-scale (local, dispersed) and large-scale (central, remote) solar/hydrogen generation facilities can be established in balance with prevailing societal-selection dictates. Involving a readily storable, transportable ‘energy currency’, then-existing hydrogen-energy systems can be inter-tied as desired, providing load-management-related economic advantages to both the energy-user and the ‘energy utility’ of that era. Future solar/hydrogen-electric residences might, as is illustrated, buy and sell hydrogen and electricity in a ‘grid-cooperative’ arrangement.The salient operative question concerns the efficacy of ‘conventional wisdom’ in the energy free-market decision-making process. Will early-enough, adequate level-of-effort programmes be implemented to ensure non-disruptive meeting of tomorrow's demand worldwide? In an aura of business-as-usual, solar/hydrogen's timely contribution to ‘picking up the load’ from exhaustible fossil fuels in the face of still-escalating world energy demand is judged most problematic. Consequently, an unprecedented cooperative world effort for the research, development, demonstration and deployment of solar hydrogen energy delivery capabilities is suggested.     

Acrylamide in almond products

Acrylamide was determined in 86 different almond products, such as roasted almonds, almond-containing bakery products, raw almonds, and marzipan. The highest acrylamide concentrations were found in dark roasted almonds, while only moderate acrylamide contents were determined in bakery products. Roasting experiments under different process conditions showed that acrylamide increases with time and that temperature has a much stronger effect on acrylamide formation than time. During roasting reducing sugars are consumed faster and to a larger extent than free asparagine, suggesting that the content of reducing sugars may be a critical factor for acrylamide formation in roasted almonds. Acrylamide was found to decrease in roasted almonds during storage at room temperature.     

Electrochemical degradation of the β-blocker metoprolol by Ti/Ru 0.7 Ir 0.3 O 2 and Ti/SnO 2-Sb electrodes

Electrochemical oxidation has been proposed for the elimination of pesticides, pharmaceuticals and other organic micropollutants from complex waste streams. However, the detrimental effect of halide ion mediators and the generation of halogenated by-products in this process have largely been neglected thus far. In this study, we investigated the electrochemical oxidation pathways of the β-blocker metoprolol in reverse osmosis concentrate (ROC) from a water reclamation plant using titanium anodes coated with Ru_0.7Ir_0.3O₂ or SnO₂-Sb metal oxide layers. The results of liquid chromatography-mass spectrometry analysis indicated that irrespective of the electrode coating the same oxidant species participated in electrochemical transformation of metoprolol in ROC. Although Ti/SnO₂-Sb exhibited higher oxidizing power for the same applied specific electrical charge, the generation of large fractions of chloro-, chloro-bromo- and bromo derivatives was observed for both electrode coatings. However, degradation rates of metoprolol and its degradation products were generally higher for the Ti/SnO₂-Sb anode. Chemical analyses of metoprolol and its by-products were complemented with bioanalytical tools in order to investigate their toxicity relative to the parent compound. Results of the bioluminescence inhibition test with Vibrio fischeri and the combined algae test with Pseudokirchneriella subcapitata indicated a substantial increase in non-specific toxicity of the reaction mixture due to the formed halogenated by-products, while the specific toxicity (inhibition of photosynthesis) remained unchanged.     

Fatty acid composition, cooking loss and texture of beef patties from meat of bulls fed different fats

The effect of fatty acid composition on the properties of patties standardised to contain 15% fat was studied. Patties were made of beef from 36 Brown Swiss bulls fed on six different diets with five of them containing additional fats to achieve a high variability in body lipid composition. When the feed contained fullfat oilseeds (rapeseed, sunflower seed, linseed), the proportions of some nutritionally favourable fatty acids were increased in the patties. Patties made from the meat of bulls fed linseed and coconut oil could be distinguished in a sensory triangle test from most other groups. Cooking loss and instrumental texture properties showed no relation to fatty acid composition of patties. Cooking only slightly decreased the proportion of saturated fatty acids in favour of polyunsaturated fatty acids. In conclusion, widely differing dietary fats can be fed to bulls without risking major effects on texture of beef patties.     

Environmental risk assessment of fluctuating diazinon concentrations in an urban and agricultural catchment using toxicokinetic-toxicodynamic modeling

Temporally resolved environmental risk assessment of fluctuating concentrations of micropollutants is presented. We separated the prediction of toxicity over time from the extrapolation from one to many species and from acute to sublethal effects. A toxicokinetic-toxicodynamic (TKTD) model predicted toxicity caused by fluctuating concentrations of diazinon, measured by time-resolved sampling over 108 days from three locations in a stream network, representing urban, agricultural and mixed land use. We calculated extrapolation factors to quantify variation in toxicity among species and effect types based on available toxicity data, while correcting for different test durations with the TKTD model. Sampling from the distribution of extrapolation factors and prediction of time-resolved toxicity with the TKTD model facilitated subsequent calculation of the risk of undesired toxic events. Approximately one-fifth of aquatic organisms were at risk and fluctuating concentrations were more toxic than their averages. Contribution of urban and agricultural sources of diazinon to the overall risk varied. Thus using fixed concentrations as water quality criteria appears overly simplistic because it ignores the temporal dimension of toxicity. However, the improved prediction of toxicity for fluctuating concentrations may be small compared to uncertainty due to limited diversity of toxicity data to base the extrapolation factors on.     

Value proposition of IoT-based products and services: a framework proposal

Electronic Markets - The IoT can help firms to innovate and to address new business opportunities. However, many companies face difficulties in developing products and services based on the IoT...     

pH dependence of steroid hormone--organic matter interactions at environmental concentrations

The interaction of estradiol, estrone, progesterone and testosterone with environmentally relevant concentrations of Aldrich humic acid, alginic acid and tannic acid was studied using solid-phase microextraction (SPME). Since bulk organic matter and certain hormones such as estradiol and estrone contain dissociable functional groups, the effect of pH on sorption was investigated as this will influence their fate and bioavailability. For humic acid and tannic acid, sorption was strongest at acidic pH when the bulk organic matter was in a non-dissociated form and decreased when they became partially negatively charged. At acidic and neutral pH the strength of partitioning was influenced by hormone functional groups content, with the strongest sorption observed for progesterone and estrone. At alkaline pH conditions, when the bulk organics were dissociated, sorption decreased considerably (up to a factor of 14), although the non-dissociated hormones testosterone and progesterone indicated greater sorption to humic acid at pH 10 compared to the partially deprotonated estradiol and estrone. This study demonstrates that SPME can be used to assess organic matter sorption behaviour of a selected range of micropollutants and at environmentally relevant organic matter concentrations.