Tensioactive properties of rhamnolipids produced by a Pseudomonas aeruginosa strain were investigated in the presence or absence of Sr(2+) or Pb(2+). Surface and interfacial properties, and aggregate forming properties and morphologies were studied by various techniques including scanning electron microscopy. When the pH of a rhamnolipid aqueous solution (40 mg/l) was increased from 5 to 8, irregular vesicles gradually took the shape of oligo-vesicles, then regular vesicles and finally smaller spherical vesicles. Addition of metal ions controlled the aggregates' morphology and stability, and influenced the surface and interfacial behavior of rhamnolipid solutions.

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Introduction: Favorable outcomes with continuous flow devices (CFD) have enticed clinicians to implant CFD in patients smaller than the suggested body surface area (BSA) criteria of >1.5 m 2 . Despite limited data, the VAD community is using CFD in patients down to a BSA of 0.7m 2 . For this reason, we sought to examine the use of CFD in adults with BSA ≤1.5 m 2 and compare outcomes to adult patients with BSA >1.5m 2 . Methods: CFD implants in adults (>18 years) from 04/2008 to 09/2014 were identified using the Interagency Registry for Mechanically Assisted Circulatory Support (INTERMACS) database. Patients were divided into two cohorts based on BSA. Patient characteristics and post implant outcomes including mortality, transplant, and adverse events were compared between the two cohorts. Results: Of adults (11142) undergoing CFD implants 2% (239) had BSA of ≤1.5m 2 ; BSA median 1.4m 2 [0.76 – 1.5 m 2 ]. One patient had BSA <1.0m 2 , 6% (15) 1.0-1.2m 2 and 93% (223) >1.2-1.5m 2 . Pre-implant patient characteristics were similar between the two groups except gender and INTERMACS profile [Table]. Overall survival (p=0.8) and favorable outcomes at 1-year were similar between the two groups; however, fewer patients with BSA ≤1.5m 2 were transplanted (p<0.01) [Figure]. There were more bleeding events and infection; however, less renal dysfunction and right heart failure in patients with BSA ≤1.5m 2 [Table]. Conclusion: CFDs can be safely used in smaller adult patients. The outcomes are favorable but clinicians must be mindful that the adverse event profile is different in smaller patients. These results are reassuring for the recent trend in the VAD community for placing CFDs in smaller patients.

A 3-year study evaluated the effect of different seed-priming techniques on the performance of two bread wheat (Triticum aestivum L.) cultivars, Seher-2006 and Shafaq-2006, planted in rows spaced at 22.5 or 30 cm. Three seed priming techniques—on-farm priming, hydropriming, and osmopriming (using CaCl2)—and an untreated control (dry seeds) were included in the study. Seed priming resulted in earlier and more uniform crop emergence and improved allometric and yield-related traits compared with untreated seeds. Hydropriming and osmopriming significantly improved the allometric traits of Seher-2006 planted at 22.5-cm row spacing and Shafaq-2006 planted at 30-cm row spacing each year. The combination of osmopriming and 30-cm row spacing produced the highest number of productive tillers, number of grains per spike and 1000-grain weight across all experimental years. The highest grain yield and harvest index were recorded for osmopriming and 22.5-cm row spacing each year. Shafaq-2006 produced higher biological yield, whereas Seher-2006 produced the higher grain yield and harvest index. Osmoprimed seeds planted at 22.5-cm row spacing recorded the highest economic returns and benefit:cost ratios in both cultivars. In conclusion, planting osmoprimed seeds of wheat in 22.5-cm spaced rows could be effectively used to increase productivity and economic returns.

The ionic conductivity of poly(ethylene oxide) and poly(propylene oxide) in pure solution form, individually complexed with salts of Na + and Li + , with and without plasticizer (propylene carbonate) and in blended form with individual salt with and without plasticizer, was studied. The conductance measurements were made at various concentrations of salt polymer complexes and at different temperatures. The effects of temperature and plasticizer concentration were measured from Arrhenius conductance plots. It is shown that the addition of salts in pure PEO increases conductance many times. The plasticizer has also same effect. The blending of PEO with PPO gives enhanced conductivity as compared to pure PEO. The activation energies were determined for all the systems which gave higher values for pure PEO and the value decreases with the addition of Li and Na salts and further decreases with the addition of plasticizer. The blending has also lowered the activation energy values which mean that incorporation of PPO in PEO has decreased crystallinity and the amorphous region has increased the local mobility of polymer chains resulting in lower activation energies.

Static light scattering and viscosity measurements were performed on different molecular weight poly (ethylene oxide) to see the formation of aggregates in its dilute solutions. Viscosity measurements were carried out for PEO samples in water and methanol at 20-458C and in chloroform at 20-308C. Using Huggin's equation, the viscosity plots showed distinct upward curvature indicating the presence of aggregates in both PEO/H 2 O and PEO/CH 3 OH solutions The [Z] values for PEO/H 2 O and PEO/CH 3 OH system were 2-4 times as large as observed for other linear flexible polymers in good solvents thus showing extensive coil swelling/aggregation. This is also apparent from the exponent a values of the Mark-Houwink-Sakurada equation. Light Scattering results using Zimm method showed that aggregation occurred in low molecular weight samples; however, in higher molecular weight samples there was a little evidence for aggregation both in water and methanol.

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