Predictive Validity of an Empirical Approach for Selecting Promising Message Topics: A Randomized‐Controlled Study

Several message topic selection approaches propose that messages based on beliefs pretested and found to be more strongly associated with intentions will be more effective in changing population intentions and behaviors when used in a campaign. This study aimed to validate the underlying causal assumption of these approaches which rely on cross‐sectional belief–intention associations. We experimentally tested whether messages addressing promising themes as identified by the above criterion were more persuasive than messages addressing less promising themes. Contrary to expectations, all messages increased intentions. Interestingly, mediation analyses showed that while messages deemed promising affected intentions through changes in targeted promising beliefs, messages deemed less promising also achieved persuasion by influencing nontargeted promising beliefs. Implications for message topic selection are discussed.     

Iron Oxide‐Labeled Collagen Scaffolds for Non‐Invasive MR Imaging in Tissue Engineering

Non‐invasive imaging holds significant potential for implementation in tissue engineering. It can be used to monitor the localization and function of tissue‐engineered implants, as well as their resorption and remodelling. Thus far, however, the vast majority of effort in this area of research have focused on the use of ultrasmall super‐paramagnetic iron oxide (USPIO) nanoparticle‐labeled cells, colonizing the scaffolds, to indirectly image the implant material. Reasoning that directly labeling scaffold materials might be more beneficial (enabling imaging also in the case of non‐cellularized implants), more informative (enabling the non‐invasive visualization and quantification of scaffold degradation), and easier to translate into the clinic (cell‐free materials are less complex from a regulatory point‐of‐view), three different types of USPIO nanoparticles are prepared and incorporated both passively and actively (via chemical conjugation; during collagen crosslinking) into collagen‐based scaffold materials. The amount of USPIO incorporated into the scaffolds is optimized, and correlated with MR signal intensity, showing that the labeled scaffolds are highly biocompatible, and that scaffold degradation can be visualized using MRI. This provides an initial proof‐of‐principle for the in vivo visualization of the scaffolds. Consequently, USPIO‐labeled scaffold materials seem to be highly suitable for image‐guided tissue engineering applications.     

Micrometer‐Scale Porous Buckling Shell Actuators Based on Liquid Crystal Networks

Micrometer‐scale liquid crystal network (LCN) actuators have potential for application areas like biomedical systems, soft robotics, and microfluidics. To fully harness their power, a diversification in production methods is called for, targeting unconventional shapes and complex actuation modes. Crucial for controlling LCN actuation is the combination of macroscopic shape and molecular‐scale alignment in the ground state, the latter becoming particularly challenging when the desired shape is more complex than a flat sheet. Here, one‐step processing of an LCN precursor material in a glass capillary microfluidic set‐up to mold it into thin shells is used, which are stretched by osmosis to reach a diameter of a few hundred micrometers and thickness on the order of a micrometer, before they are UV crosslinked into an LCN. The shells exhibit radial alignment of the director field and the surface is porous, with pore size that is tunable via the osmosis time. The LCN shells actuate reversibly upon heating and cooling. The decrease in order parameter upon heating induces a reduction in thickness and expansion of surface area of the shells that triggers continuous buckling in multiple locations. Such buckling porous shells are interesting as soft cargo carriers with capacity for autonomous cargo release.     

Synthesis,characterisation and use of 2-tetradecylcyclobutanone together with other cyclobutanones as markers for irradiated liquid whole egg

The synthesis and characterisation of 2-tetradecylcyclobutanone (TCB) is described. Both 2-dodecykyclobutanone and TCB were shown to be present in liquid whole egg irradiated at doses of 2.5 and 10.0 kGy. These compounds were absent from the unirradiated pasteurised samples. Using gas chromatography and infrared spectroscopy, there was also evidence for the presence in irradiated egg of 2-tetradeccnyl- and 2-tetradecadienylyclobutanone which are formed from oleic and linoleic acids, respectively. Authentic standards for these unsaturated cyclobutanones were not available commercially but the presence of 2-tetra-decenylcyclobutanone was substantiated by hydrogenating the egg extracts so converting this unsaturated cyclobutanone to TCB. Saturated and unsaturated cyclobutanones appear to be specific products of irradiation and are potential markers for detection of irradiated liquid egg and probably other fat-containing foods.     

Models for Audiovisual Fusion in a Noisy-Vowel Recognition Task

This paper presents a study of models for audiovisual (AV) fusion in a noisy-vowel recognition task. We progressively elaborate audiovisual models in order to respect the major principle demonstrated by human subjects in speech perception experiments (the synergy principle): audiovisual identification should always be more efficient than auditory-alone or visual-alone identification. We first recall that the efficiency of audiovisual speech recognition systems depends on the level at which they fuse sound and image: four AV architectures are presented, and two are selected for the following of the study. Secondly, we show the importance of providing a contextual input linked to the Signal-to-Noise Ratio (SNR) in the fusion process. Then we propose an original approach using an efficient nonlinear dimension reduction algorithm (curvilinear components analysis) in order to increase the performances of the two AV architectures. Furthermore, we show that this approach allows an easy and efficient estimation of the reliability of the audio sensor in relation to SNR, that this estimation can be used to control the AV fusion process, and that it significantly improves the AV performances. Hence, altogether, nonlinear dimension reduction, context estimation and control of the fusion process enable us to respect the synergy criterion for the two most used architectures.     

Multihour engineering and traffic routing optimization in hierarchical telephone networks

Classical hierarchical routing in telephone networks is extended to a wider class called out-of-chain routing in such a way that some useful properties of hierarchical routing are retained. This new routing pattern offers more potential paths than the fixed hierarchical one and can be introduced as a dynamic routing where the fixed alternate sequences change at some predetermined instants during the day. The effect of this new routing pattern on the network performances is examined. The main topic of this paper is to present heuristic methods used to optimise such routings in large networks. We show on artificial networks that the throughput of a given network can be significantly improved by suitable routing choices. We demonstrate that the integration of routing changes within a multihour dimensioning process is possible but the lack of realistic data does not permit at this time to quantify the value of routing optimization on real networks.     

Near-zero triangular location through time-slotted mobility prediction

To setup efficient wireless mesh networks, it is fundamental to limit the overhead needed to localize a mobile user. A promising approach is to rely on a rendezvous-based location system where the current location of a mobile node is stored at specific nodes called locators. Nevertheless, such a solution has a drawback, which happens when the locator is far from the source–destination shortest path. This results in a triangular location problem and consequently in increased overhead of signaling messages. One solution to prevent this problem would be to place the locator as close as possible to the mobile node. This requires however to predict the mobile node’s location at all times. To obtain such information, we define a mobility prediction model (an agenda) that, for each node, specifies the mesh router that is likely to be the closest to the mobile node at specific time periods. The location service that we propose formalizes the integration of the agenda with the management of location servers in a coherent and self-organized fashion. To evaluate the performance of our system compared to traditional approaches, we use two real-life mobility datasets of Wi-Fi devices in the Dartmouth campus and Taxicabs in the bay area of San Francisco. We show that our strategy significantly outperforms traditional solutions; we obtain gains ranging from 39 to 72% compared to the centralized scheme and more than 35% compared to a traditional rendezvous-based solution.     

In Situ Generation of n-Type Dopants by Thermal Decarboxylation

Molecular doping is a powerful and increasingly popular approach toward enhancing electronic properties of organic semiconductors (OSCs) past their intrinsic limits. The development of n-type dopants has been hampered, however, by their poor stability and high air-reactivity, a consequence of their generally electron rich nature. Here, the use of air-stable carboxylated dopant precursors is reported to overcome this challenge. Active dopants are readily generated in solution by thermal decarboxylation and applied in n-type organic field-effect transistors (OFETs). Both 1,3-dimethylimidazolium-2-carboxylate (CO₂-DMI) and novel dopant 1,3-dimethylbenzimidazolium-2-carboxylate (CO₂-DMBI) are applied to n-type OFETs employing well-known organic semiconductors (OSCs) P(NDI2OD-T2), PCBM, and O-IDTBR. Successful improvement of performance in all devices demonstrates the versatility of the dopants across a variety of OSCs. Experimental and computational studies indicate that electron transfer from the dopant to the host OSC is preceded by decarboxylation of the precursor, followed by dimerization to form the active dopant species. Transistor studies highlight CO₂-DMBI as the most effective dopant, improving electron mobility by up to one order of magnitude, while CO₂-DMI holds the advantage of commercial availability.     

New sources of resistance to Acanthoscelides obtectus (Say) and Zabrotes subfasciatus Boheman (Coleoptera: Bruchidae) in mature seeds of five species of Phaseolus

The importance of carefully applied bioassay techniques is highlighted for identifying resistance of Phaseolus spp to the bruchids Acanthoscelides obtectus (Say) and Zabrotes subfasciatus Boheman. Two potential sources of resistance are identified amongst the varieties of P. vulgaris screened. In one the presence of a lectin-like protein (LLP) was identified, which has previously been associated with resistance, while in the other, resistance may be linked to the presence of a novel protein, similar to but not the same as LLP. The use of anti-LLP antibodies are suggested as a useful tool for distinguishing between resistant and susceptible varieties. Five varieties of P. lunatus and six of P. acutifolius are shown to be resistant to A. obtectus, and the potential is recognized for transferring resistant genes to P. vulgaris via interspecific crosses.