Silver electrodeposition from air and water-stable ionic liquid: An environmentally friendly alternative to cyanide baths

The influence of temperature on the kinetics and the morphology of silver deposits obtained from an air and water-stable ionic liquid (the 1-butyl-3-methyl imidazolium tetrafluoroborate) was studied by means of cyclic voltammetry and chronoamperometry. The nucleation and growth mechanisms have been investigated and the effect of temperature evaluated up to 200 °C. Dense, pure and very thin (about 0.3 μm) silver coatings, with decorative properties, have been obtained on commercial copper electrodes at different temperatures. The characterization of the deposits morphology has been performed by visual investigation and SEM microscopy. Data about thickness were acquired by Calotest® measurements. The deposits result constituted by pure silver as determined by combination of EDX microanalysis and Auger Electron Spectroscopy (AES). The deposition method promises to be a new, environmentally friendly, method for silver electrodeposition which is the reason for the absence of cyanide and volatile toxic solvents in the electroplating bath.     

Estimation of thermal diffusivity of foods using transfer functions

The effective thermal diffusivity of foodstuffs was estimated from time-temperature histories in the geometric center of samples exposed to heating and cooling processes.Transfer functions methodology was used as an alternative method to estimate the thermal diffusivity assuming that conduction was the main heat transfer mechanism. The samples were characterized as delayed first-order systems with unit gain, dead time (L) and time constant (τ).The results were compared with those obtained from the f_h value and with results reported in the literature.     

There's more to touch than meets the eye: The salience of object attributes for haptics with and without vision.

The availability and salience of object attributes under haptic exploration, with and without vision, were assessed by 2 tasks in which Ss sorted objects that varied factorially in size, shape, texture, and hardness. In the directed-discrimination task, Ss were instructed to sort along a particular dimension. Although levels on all dimensions were easily discriminated, shape was relatively less so for haptic explorers without vision, as was hardness for those using vision and haptics. Size was least discriminable for both groups. In the free-sorting task, Ss were to sort objects by similarity. Three groups used haptic exploration only; these were differentiated by the experimenters' definition of object similarity: unbiased haptics, haptically biased haptics, haptics plus visual imagery. A 4th group used vision as well as haptics, with instructions like those of the unbiased haptics group. Results support the contention that the haptic and visual systems have distinct encoding pathways, with haptics oriented toward the encoding of substance rather the shape. This may reflect a direct influence of haptic exploratory procedures. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Synthesis and Evaluation of Voltage-Gated Sodium Channel Blocking Pyrroline Derivatives Endowed with Both Antiarrhythmic and Antioxidant Activities

Under the hypothesis that cardioprotective agents might benefit from synergism between antiarrhythmic activity and antioxidant properties, a small series of mexiletine analogues were coupled with the 2,2,5,5-tetramethylpyrroline moiety, known for its antioxidant effect, in order to obtain dual-acting drugs potentially useful in the protection of the heart against post-ischemic reperfusion injury. The pyrroline derivatives reported herein were found to be more potent as antiarrhythmic agents than mexiletine and displayed antioxidant activity. The most interesting tetramethylpyrroline congener, a tert-butyl-substituted analogue, was at least 100 times more active as an antiarrhythmic than mexiletine.     

Bone Marrow-Mesenchymal Stromal Cell Secretome as Conditioned Medium Relieves Experimental Skeletal Muscle Damage Induced by Ex Vivo Eccentric Contraction

Bone marrow-mesenchymal stem/stromal cells (MSCs) may offer promise for skeletal muscle repair/regeneration. Growing evidence suggests that the mechanisms underpinning the beneficial effects of such cells in muscle tissue reside in their ability to secrete bioactive molecules (secretome) with multiple actions. Hence, we examined the effects of MSC secretome as conditioned medium (MSC-CM) on ex vivo murine extensor digitorum longus muscle injured by forced eccentric contraction (EC). By combining morphological (light and confocal laser scanning microscopies) and electrophysiological analyses we demonstrated the capability of MSC-CM to attenuate EC-induced tissue structural damages and sarcolemnic functional properties’ modifications. MSC-CM was effective in protecting myofibers from apoptosis, as suggested by a reduced expression of pro-apoptotic markers, cytochrome c and activated caspase-3, along with an increase in the expression of pro-survival AKT factor. Notably, MSC-CM also reduced the EC-induced tissue redistribution and extension of telocytes/CD34⁺ stromal cells, distinctive cells proposed to play a “nursing” role for the muscle resident myogenic satellite cells (SCs), regarded as the main players of regeneration. Moreover, it affected SC functionality likely contributing to replenishment of the SC reservoir. This study provides the necessary groundwork for further investigation of the effects of MSC secretome in the setting of skeletal muscle injury and regenerative medicine.     

Cyclic Nigerosyl-Nigerose as Oxygen Nanocarrier to Protect Cellular Models from Hypoxia/Reoxygenation Injury: Implications from an In Vitro Model

Heart failure (HF) prevalence is increasing among the aging population, and the mortality rate remains unacceptably high despite improvements in therapy. Myocardial ischemia (MI) and, consequently, ischemia/reperfusion injury (IRI), are frequently the basis of HF development. Therefore, cardioprotective strategies to limit IRI are mandatory. Nanocarriers have been proposed as alternative therapy for cardiovascular disease. Controlled reoxygenation may be a promising strategy. Novel nanocarriers, such as cyclic nigerosyl-nigerose (CNN), can be innovative tools for oxygen delivery in a controlled manner. In this study we analyzed new CNN-based formulations as oxygen nanocarriers (O₂-CNN), and compared them with nitrogen CNN (N₂-CNN). These different CNN-based formulations were tested using two cellular models, namely, cardiomyoblasts (H9c2), and endothelial (HMEC) cell lines, at different concentrations. The effects on the growth curve during normoxia (21% O₂, 5% CO₂ and 74% N₂) and their protective effects during hypoxia (1% O₂, 5% CO₂ and 94% N₂) and reoxygenation (21% O₂, 5% CO₂ and 74% N₂) were studied. Neither O₂-CNN nor N₂-CNN has any effect on the growth curve during normoxia. However, O₂-CNN applied before hypoxia induces a 15–30% reduction in cell mortality after hypoxia/re-oxygenation when compared to N₂-CNN. O₂-CNN showed a marked efficacy in controlled oxygenation, which suggests an interesting potential for the future medical application of soluble nanocarrier systems for MI treatment.     

Thai Tea Seed Oil and Virgin Olive Oil Similarly Reduce Plasma Lipids: A Pilot Study within a Healthy Adult Male Population

The potential cardiovascular benefit of virgin olive oil (VOO) is widely recognized. However, the use of VOO at very high cooking temperatures makes these oils poorly suited for many Asian dishes. The use of tea seed oil (TSO) is increasing in Thailand, with TSO having a higher smoke point than VOO. The current study examines the effects of daily TSO intake in healthy adults. In a randomized, single-blind crossover design, 12 men consumed for 3 weeks 40 g day⁻¹ of food prepared with either TSO or VOO as a cooking oil. Plasma lipids, thiobarbituric acid reactive substances (TBARS), and oxidant defense enzyme activities are measured before and after each 3-week intervention period. Gas chromatography analysis of TSO and VOO demonstrates that both oils are equally high in monounsaturated fatty acid. The dietary incorporation of TSO and VOO for three weeks reduces low-density lipoprotein cholesterol (LDL-C) concentrations by 15% and 13%, respectively; with total cholesterol (TC) levels lowered by 10% in both groups. No significant changes in TBARS or antioxidant enzyme activity is observed. These results support the concept that Thai TSO can be utilized as a suitable and healthy alternative oil for high-temperature cooking in many Thai and Asian diets. Practical Applications: Tea seed oil from Camellia oleifera grown in Thailand has been recently reported to favorably lower lipid profiles in hamsters fed a high-fat diet in a manner similar to feeding refined olive oil or grapeseed oil. A pilot crossover trial is conducted to compare the effects of three weeks of daily intake of either TSO or VOO in healthy human adults. Consumption of both oils produced significant reductions in TC and LDL-C. Thai TSO leads to favorable lipid profiles and is a reasonable choice for many Thai and Asian food recipes.     

Fluorinated Polyphosphazenes: A Survey

A general survey of fluorinated phosphazene polymers starting from their synthesis in 1965 to recent times is presented. Various types of fluorinated phosphazenes are described depending on the way fluorine atoms are connected to the polyphosphazene skeleton. The characterization, properties and practical utilization of these compounds in different domains are critically discussed.     

Nutrient balance of shifting cultivation by burning or mulching in the Eastern Amazon – evidence for subsoil nutrient accumulation

For over a hundred years shifting cultivation with slash-and-burn land preparation has been the predominant type of land use by smallholders in the Bragantina region of the Brazilian Eastern Amazon. This study contrasts the nutrient balance of slash-and-burn agriculture with a fire-free cultivation. Therefore, one half of a 3.5-year-old (28.7 t DM ha^–1) and a 7-year-old woody fallow vegetation (46.5 t DM ha^–1) was burnt and the other half mulched, leaving the biomass as a surface residue. Subsequently, a sequence of maize, beans and cassava was cropped for 1.5 year. Burning the 3.5- and 7-year-old fallow removed 97 and 94% of the C, 98 and 96% of the N, 90 and 63% of the P-stocks, and between 45 and 70% of the cations K, Mg and Ca of the aboveground biomass by volatilization or ash-particle transfer. These losses were avoided with the slash-and-mulch land preparation. Mulching did not increase the losses of nutrients by leaching, despite the high amount of rapidly decomposing surface mulch. Also the length of preceding fallow had no significant influence on leaching losses. At a depth of 3 m, leached nutrients were quantitatively negligible in both treatments. Comparing the nutrient fluxes at soil depths of 0.9 m, 1.8 m and 3 m, the amounts of all mobile nutrients, and also of chloride and sodium were markedly reduced during percolation and must have been retained. It is likely that nutrient retention in the subsoil layer is only temporary, emphasizing the need for a rapid re-establishment of the naturally deep-rooting secondary vegetation after abandonment of sites to enable uptake of these nutrients. The overall nutrient balance was highly negative for slash-and-burn. 291 and 403 kg N ha^–1, 21 and 18 kg P ha^–1, and 70 and 132 kg K ha^–1 were removed from the burnt plots with a preceding fallow of 3.5 and 7 years, respectively. A reduced fallow period (3.5 years), which is a common trend in the region, resulted in a higher mean annual rate of nutrient loss averaged over the duration of the cycle than a fallow period of 7 years. Eliminating the burning losses by mulching brought the agricultural system back to an equilibrated or even slightly positive nutrient balance, even after a reduced fallow period. Thus, slash-and-mulch is a viable alternative to maintain agricultural productivity and ecosystem functioning.