Addition of a polarising microscope to the Weissenberg Rheogoniometer

This article describes modifications to a sophisticated commercial rheometer, the Weissenberg Rheogoniometer, to allow a sample in the cone and plate or parallel‐plate geometries to be observed with a high‐quality polarizing microscope. The addition of the microscope does not interfere with the measuring system in any way, so that samples can be observed in the course of rheological experiments.

The restricted seed rain of a mistletoe specialist

Specialist frugivores are the dominant consumers of mistletoe fruit in many regions and have been shown to intensify infections of host plants as a result of their rapid gut passage rates and dependence on existing infections. The role of specialist frugivores in long distance dispersal of mistletoe and establishment of new infections is unclear, and has not been explicitly evaluated previously. Here we critically examine the premise that specialists are the dominant dispersers by examining the role of an Australian mistletoe specialist (mistletoebird Dicaeum hirundinaceum Dicaeidae) in dispersing mistletoe (Amyema preissii Santalales: Loranthaceae) seeds beyond infected host stands. We use two primary lines of evidence - presence of birds using remote call recorders, and presence of dispersed seeds via surveys for defecated seeds on host branches. The observed and inferred movements of the mistletoebird were wholly restricted to habitat patches containing mistletoe, and this bird was not observed to transport seeds to nearby uninfected host stands within the study system. While mistletoe specialists may provide much of the within-stand dispersal service for mistletoes, this serves only to aggregate and intensify existing infections. We suggest that long distance dispersal of mistletoe seeds beyond existing hosts and infection centres is not performed by these dietary specialists, these services more likely to be provided by generalist frugivores and other occasional mistletoe fruit consumers.

Real-time, in-situ, extinction spectroscopy studies on silver-nanoseed formation

In this paper, real-time extinction spectroscopy was employed to analyze in situ the fast formation process of silver seeds. The influencing factors for silver-seed formation, including the concentration of the reducer (NaBH 4), the amount of stabilizer (citrate), and the addition procedure of NaBH4, were evaluated. The configuration of the surface plasmon resonance (SPR) spectra of silver nanoparticles, which reflected the morphology of the produced silver seeds, was found to be distinctly affected by the NaBH4 concentration. Homogeneous silver nanoparticles were obtained when the added NaBH4 was lower in concentration than 2.00 mM. In contrast, higher concentrations of reducing agent (>3.00 mM NaBH4) resulted in uneven silver nanoparticles. Mie theory was applied to clarify the correlation of the SPR and the size of the silver seeds. Repeated additions of a small amount of the reducing agent could increase the monodispersity and isotropy of silver seeds. Real-time extinction spectroscopy is a convenient technique that achieves the in-situ and nondestructive measurement of intermediates in the formation process of silver nanoseeds.

Effect of Ag addition on the corrosion properties of Sn-based solder alloys

Corrosion properties of three different Sn-Ag lead free solder alloys have been investigated in 0.3 wt% Na₂SO₄ solution as corrosive environment. As cast solder alloy was analyzed by X-ray diffraction (XRD) and scanning electron microscopy (SEM). Volume fractions of the Ag₃Sn in the solders were determined by image analysis technique. Pitting potential and corrosion potential for the alloys were determined by potentiodynamic tests. Electrochemical impedance spectroscopy (EIS) was carried out to measure the film and charge transfer resistance. Alloys with lower Ag content have been found as better corrosion resistance material.

ICT to enhance the triangle of life : the soil, the seed, and the life-giver farmer

This paper reports on the outcomes of an ICT enabled social sustainability project “Green Lanka1” trialled in the Wilgamuwa village, which is situated in the Dambulla district of Sri Lanka. The main goals of the project were focused towards the provision of information about market prices, transportation options, agricultural decision support and modern agriculture practices of the farmer communities to improve their livelihood with the effective use of technologies. The project used Web and Mobile (SMS) enabled systems. The Green Lanka project was sponsored by the Information Communication Technology Agency (ICTA) of Sri Lanka under the Institutional Capacity Building Programme (ICBP) grant scheme which was sponsored by the World Bank. Six hundred families in Wilgamuwa village participated in the project activities. The project was designed, executed and studied through an Action Research approach. The lessons learned through the project activities provide an important understanding of the complex interaction between different stakeholders in the process of implementation of ICT enabled solutions within digitally divided societies. The paper analyses the processes used to reduce the resistance to change and improved involvement of farmer communities in ICT enabled projects. It also analyses the interaction between stakeholders involved in design and implementation of the project activities to improve the chances of project success.

Imparting sensitization resistance to an Al-5Mg alloy via Nd addition

Low-level Nd additions, up to 0.17 wt%, were added to Al-5Mg to explore the impact on the subsequent degree of sensitization. Following heat treatment at 150°C for 1 day and 7 days, nitric acid mass loss (NAMLT) tests revealed that additions of >0.11% Nd were effective at decreasing the amount of subsequent intergranular attack.

The energetic and survival costs of growth in free-ranging chipmunks

The growth/survival trade-off is a fundamental aspect of life-history evolution that is often explained by the direct energetic requirement for growth that cannot be allocated into maintenance. However, there is currently no empirical consensus on whether fast-growing individuals have higher resting metabolic rates at thermoneutrality (RMRt) than slow growers. Moreover, the link between growth rate and daily energy expenditure (DEE) has never been tested in a wild endotherm. We assessed the energetic and survival costs of growth in juvenile eastern chipmunks (Tamias striatus) during a year of low food abundance by quantifying post-emergent growth rate (n = 88), RMRt (n = 66), DEE (n = 20), and overwinter survival. Both RMRt and DEE were significantly and positively related to growth rate. The effect size was stronger for DEE than RMRt, suggesting that the energy cost of growth in wild animals is more likely to be related to the maintenance of a higher foraging rate (included in DEE) than to tissue accretion (included in RMRt). Fast growers were significantly less likely to survive the following winter compared to slow growers. Juveniles with high or low RMRt were less likely to survive winter than juveniles with intermediate RMRt. In contrast, DEE was unrelated to survival. In addition, botfly parasitism simultaneously decreased growth rate and survival, suggesting that the energetic budget of juveniles was restricted by the simultaneous costs of growth and parasitism. Although the biology of the species (seed-storing hibernator) and the context of our study (constraining environmental conditions) were ideally combined to reveal a direct relationship between current use of energy and future availability, it remains unclear whether the energetic cost of growth was directly responsible for reduced survival.

Effect of sorghum flour addition on resistant starch content, phenolic profile and antioxidant capacity of durum wheat pasta

Foods containing elevated levels of health functional components such as resistant starch and polyphenolic antioxidants may have beneficial effects on human health. Pasta incorporating either red sorghum flour (RSF) or white sorghum flour (WSF) each at 20%, 30% and 40% substitution of durum wheat semolina (DWS) was prepared and compared to pasta made from 100% DWS (control) for content of starch fractions, phenolic profile and antioxidant capacity, before and after cooking. Total, digestible and resistant starch contents were determined by the AOAC method; individual phenolic acids and anthocyanins by reverse phase-HPLC analysis; total phenolic content by the Folin–Ciocalteu method and antioxidant capacity by the ABTS assay. The addition of both RSF and WSF increased the resistant starch content, bound phenolic acids, total phenolic content and antioxidant capacity at all incorporation levels compared to the control pasta; while free phenolic acids and anthocyanins were higher in the RSF-containing pasta only. Cooking did not change the resistant starch content of any of the pasta formulations. Cooking did however decrease the free phenolic acids, anthocyanins, total phenolic content and antioxidant capacity and increased the bound phenolic acids of the sorghum-containing pastas. The study suggests that these sorghum flours may be very useful for the preparation of pasta with increased levels of resistant starch and polyphenolic antioxidants.