Stereochemistry and thermal stability of tartaric acid on the intrinsically chiral Cu{531} surface

Intrinsically chiral metal surfaces provide enantiospecific reaction environments without the need of coadsorbed modifiers. Amongst the intrinsically chiral copper surfaces, Cu{531} has the smallest unit cell and the highest density of chiral sites. XPS, NEXAFS and TPD were employed to investigate the adsorption and decomposition behaviour of the two chiral enantiomers of tartaric acid on this surface. The results obtained from XPS and NEXAFS show that at saturation coverage both enantiomers of tartaric acid adsorb in a μ4 configuration through the two carboxylic groups,which are rotatedwith respect to each other by 90°±≈15°within the surface plane. At intermediate coverage the R,R enantiomer adopts a similar configuration, but the S,S enantiomer is different and shows a high degree of dissociation. Growth of multilayers is observed at high exposures when the sample is kept at below 370 K. TPD experiments show that multilayers desorb between 390 K and 470 K and decomposition of the chemisorbed layer occurs between 470 K and 600 K. The desorption spectra support a two-step decomposition mechanism with a O_C_C_O or HO–HC_CH–OH intermediate that leads to production of CO2 and CO. Enantiomeric differences are observed in the desorption features related to the decomposition of the chemisorbed layer.

Compensation and Rewards for Environmental Services (CRES) and efficient design of contracts in developing countries. Behavioral insights from a natural field experiment

The use of economic incentives for biodiversity (mostly Compensation and Reward for Environmental Services including Payment for ES) has been widely supported in the past decades and became the main innovative policy tools for biodiversity conservation worldwide. These policy tools are often based on the insight that rational actors perfectly weigh the costs and benefits of adopting certain behaviors and well-crafted economic incentives and disincentives will lead to socially desirable development scenarios. This rationalist mode of thought has provided interesting insights and results, but it also misestimates the context by which ‘real individuals’ come to decisions, and the multitude of factors influencing development sequences. In this study, our goal is to examine how these policies can take advantage of some unintended behavioral reactions that might in return impact, either positively or negatively, general policy performances. We test the effect of income's origin (‘Low effort’ based money vs. ‘High effort’ based money) on spending decisions (Necessity vs. Superior goods) and subsequent pro social preferences (Future pro-environmental behavior) within Madagascar rural areas, using a natural field experiment. Our results show that money obtained under low effort leads to different consumption patterns than money obtained under high efforts: superior goods are more salient in the case of low effort money. In parallel, money obtained under low effort leads to subsequent higher pro social behavior. Compensation and rewards policies for ecosystem services may mobilize knowledge on behavioral biases to improve their design and foster positive spillovers on their development goals.

Generic intertextuality in online social activism: the case of the It Gets Better project

The It Gets Better project has been held up as a model of successful social media activism. This article explores how narrators of It Gets Better videos make use of generic intertextuality, strategically combining the canonical narrative genres of the exemplum, the testimony, and the confession in a way that allows them to claim ‘textual authority’ and to make available multiple moral positions for themselves and their listeners. This strategy is further facilitated by the ambiguous participation frameworks associated with digital media, which make it possible for storytellers to tell different kinds of stories to different kinds of listeners at the same time, to simultaneously comfort the victims of anti-gay violence, confront its perpetrators, and elicit sympathy from ‘onlookers’. This analysis highlights the potential of new practices of online storytelling for social activism, and challenges notions that new media are contributing to the demise of common narrative traditions.

Biorefinery development through utilization of biodiesel industry by-products as sole fermentation feedstock for 1,3-propanediol production

Rapeseed meal (RSM) hydrolysate was evaluated as substitute for commercial nutrient supplements in 1,3-propanediol (PDO) fermentation using the strain Clostridium butyricum VPI 1718. RSM was enzymatically converted into a generic fermentation feedstock, enriched in amino acids, peptides and various micro-nutrients, using crude enzyme consortia produced via solid state fermentation by a fungal strain of Aspergillus oryzae. Initial free amino nitrogen concentration influenced PDO production in batch cultures. RSM hydrolysates were compared with commercial nutrient supplements regarding PDO production in fed-batch cultures carried out in a bench-scale bioreactor. The utilization of RSM hydrolysates in repeated batch cultivation resulted in a PDO concentration of 65.5 g/L with an overall productivity of 1.15 g/L/h that was almost 2 times higher than the productivity achieved when yeast extract was used as nutrient supplement.

Sampling uncertainty in gridded sea surface temperature products and Advanced Very High Resolution Radiometer (AVHRR) Global Area Coverage (GAC) data

Sea surface temperature (SST) data are often provided as gridded products, typically at resolutions of order 0.05 degrees from satellite observations to reduce data volume at the request of data users and facilitate comparison against other products or models. Sampling uncertainty is introduced in gridded products where the full surface area of the ocean within a grid cell cannot be fully observed because of cloud cover. In this paper we parameterise uncertainties in SST as a function of the percentage of clear-sky pixels available and the SST variability in that subsample. This parameterisation is developed from Advanced Along Track Scanning Radiometer (AATSR) data, but is applicable to all gridded L3U SST products at resolutions of 0.05-0.1 degrees, irrespective of instrument and retrieval algorithm, provided that instrument noise propagated into the SST is accounted for. We also calculate the sampling uncertainty of ~0.04 K in Global Area Coverage (GAC) Advanced Very High Resolution Radiometer (AVHRR) products, using related methods.

Polymerization-dependent activation of porcine γδ T-cells by proanthocyanidins

Plant-derived proanthocyanidins (PAC) have been promoted as a natural method of improving health and immune function in livestock. It has previously been shown that PAC are effective agonists for activating ruminant γδ T-cells in vitro, however effects on other livestock species are not yet clear. Moreover, the fine structural characteristics of the PAC which contribute to this stimulatory effect have not been elucidated. Here, we demonstrate activation of porcine γδ T-cells by PAC via up-regulation of CD25 (IL-2Rα) and show that 1) activation is dependent on degree of polymerization (DP), with PAC fractions containing polymers with mean DP >6 significantly more effective than fractions with mean DP <6, whilst flavan-3-ol monomers (the constituent monomeric units of PAC) did not induce CD25 expression and 2) both procyanidin and prodelphinidin-type PAC are effective agonists. Furthermore, we show that this effect of PAC is restricted to the γδ T-cell population within porcine peripheral mononuclear cells as significant CD25 up-regulation was not observed in non γδ T-cells, and no activation (via CD80/86 up-regulation) was evident in monocytes. Our results show that dietary PAC may contribute to enhancement of innate immunity in swine via activation of γδ T-cells.

Sparse density estimator with tunable kernels

A new sparse kernel density estimator with tunable kernels is introduced within a forward constrained regression framework whereby the nonnegative and summing-to-unity constraints of the mixing weights can easily be satisfied. Based on the minimum integrated square error criterion, a recursive algorithm is developed to select significant kernels one at time, and the kernel width of the selected kernel is then tuned using the gradient descent algorithm. Numerical examples are employed to demonstrate that the proposed approach is effective in constructing very sparse kernel density estimators with competitive accuracy to existing kernel density estimators.