Fatty acid desaturase systems of hen liver and their inhibition by cyclopropene fatty acids

Hen liver preparations which desaturate stearic acid at the 9,10 position to form oleic acid have been found to desaturate other saturated fatty acids of carbon chain length from 12 to 20 and 22. The 9,10-monoenoic fatty acid of the same chain length as the substrate fatty acid is the major product formed. Minor amounts of the 10,11- and 11, 12-monoenoic acids are also formed. Maximum desaturation occurred with the C₁₄ fatty acid substrate and with the fatty acids C₁₇ and C₁₈, suggesting the presence of at least two desaturating systems. The cyclopropene fatty acids, sterculic and malvalic acids, inhibited the desaturation of all thefatty acids at the 9,10 position but desaturation at the 10,11 and 11, 12 positions was affected only slightly. The effect is not due to inhibition of the primary activating enzyme, the long chain acyl CoA synthetase. Sterculic acid is a more effective inhibitor than either malvalic acid or sterculyl alcohol, probably because these cyclopropene compounds do not block the desaturating site of the enzyme as completely as sterculic acid.     

Electrophoretic deposition of carbon nanotubes

Electrophoretic deposition (EPD) has been gaining increasing interest as an economical and versatile processing technique for the production of novel coatings or films of carbon nanotubes (CNTs) on conductive substrates. The purpose of the paper is to present an up-to-date comprehensive overview of current research progress in the field of EPD of CNTs. The paper specifically reviews the preparation and characterisation of stable CNT suspensions, and the mechanism of the EPD process; it includes discussion of pure CNT coatings and CNT/nanoparticle composite films. A complete discussion of the EPD parameters is presented, including electrode materials, deposition time, electrode separation, deposition voltage and resultant electric field. The paper highlights potential applications of the resulting CNT and CNT/composite structures, in areas such as field emission devices, fuel cells, and supercapacitors.     

Zeolite Formation in Class F Fly Ash Blended Cement Pastes

Zeolite formation in Class F fly ash blended cement pastes is under investigation. A Na–P type zeolite and Zeolite Y were synthesized from Class F fly ash and NaOH solution after 2 days of aging at room temperature and 6 days of curing at 80°C. However, no zeolites formed when KOH was used. In additional experiments, a Na–P type zeolite, Zeolite Y, and chabazite developed in cement pastes blended with Class F fly ash and NaOH solution which had been aged 2 days at room temperature and then cured 6 days at temperatures ranging from room temperature to 90°C. Seeding the pastes with natural zeolites was also investigated.     

Inhibitions of cotton seedling growth by volatile ketones emitted by cover crop residues

Low-input, sustainable agriculture (LISA) systems can include soil incorporation of residues of weeds and legume cover crop species. However, both seed germination and seedling growth of crops, including cotton (Gossypium hirsutum L.), are inhibited by volatile organic compounds emitted by these residues during decomposition. A cotton seedling-growth assay was used to demonstrate that C₄ through C₉ ketones released by decomposing legume residues significantly inhibited root and shoot elongation, root and shoot fresh and dry weight gain, and cotyledon expansion. Seedling root and shoot water relationships were relatively insensitive to those components of plant residue volatile emissions. Concentration (0.0, 0.5, 1.0, 1.5, or 2.0M/cm³ sterile greenhouse soil mix) and root-zone temperature (20 or 30°C) altered the activity of the more inhibitory ketones. Molecular weight (carbon chain length), carbon chain branching, and position of the carbonyl group also influenced ketone inhibitory activity.Mention of a commercial or proprietary product does not constitute an endorsement by the U.S. Department of Agriculture.     

Gripper Design for Radio Base Station Autonomous Maintenance System

For an autonomous system to perform maintenance tasks in a networking device or a radio base station (RBS), it has to deal with a series of technological challenges ranging from identifying hardware-related problems to manipulating connectors. This paper describes the development of a robot maintenance system dedicated to detect and resolve faulty links caused by unplugged or poorly connected cables. Although the maintenance system relies on four subsystems, we significantly focus on our low-cost and efficient custom gripper solution developed to handle RJ45 Ethernet connectors. To examine our gripper, we conducted three experiments. First, a qualitative questionnaire was submitted to 30 users in the case of the teleoperated scenario of the gripper attached to a robotic arm. Similarly, we also tested the automatic operation mode. The results showed that our system is reliable and delivers a highly efficient maintenance tool in both teleoperated and autonomous operation modes. The practical experiment containing the removal or unplugging of connectors demonstrated our gripper’s ability to adequately handle these, whereas the feedback from the questionnaire pointed to a positive user experience. The automatic test assessed the gripper’s robustness against the continuous operation.

     

Interactive sonification to assist children with autism during motor therapeutic interventions

Personal and Ubiquitous Computing - Interactive sonification is an effective tool used to guide individuals when practicing movements. Little research has shown the use of interactive sonification...     

SPIDER: An availability-aware framework for the service function chain placement in distributed scenarios

The network function virtualization (NFV) paradigm replaces hardware-dependent network functions by virtual network functions (VNFs) that can be deployed in commodity hardware, including legacy servers. Consequently, the use of NFV is expected to reduce operating and capital expenses, as well as improve service deployment operation and management flexibility. For many use cases, the VNFs must be visited and invoked following a specific order of execution in order to compose a complete network service, named service function chain (SFC). Nonetheless, despite the benefits from NFV and SFC virtualization technologies, their introduction must not harm network performance and service availability. On the one hand, redundancy is seen by network service planners as a mechanism well established to combat availability issues. At same time, there is a goal to optimize resource utilization in order to reduce operational expenditure. In this article, we share our experience in the design use of a framework, named SPIDER, focused on SFC placement that considers the network infrastructure condition and the required SFC availability to define the placement strategy. The SPIDER monitors the status of infrastructure nodes and links and defines which servers the VNFs should be placed on and the number of redundant replicas needed. We present a proof-of-concept of SPIDER using Kubernetes to launch the VNFs as containers. We also use Kubernetes to forward the traffic between the VNFs, composing the service chain. We perform experiments to evaluate the runtime of SPIDER and the SFC delay under different network conditions.     

Software Development Cultures and Cooperation Problems: A Field Study of the Early Stages of Development of Software for a Scientific Community

In earlier work, I identified a particular class of end-user developers, who include scientists and whom I term ‘professional end-user developers’, as being of especial interest. Here, I extend this work by articulating a culture of professional end-user development, and illustrating by means of a field-study how the influence of this culture causes cooperation problems in an inter-disciplinary team developing a software system for a scientific community. My analysis of the field study data is informed by some recent literature on multi-national work cultures. Whilst acknowledging that viewing a scientific development through a lens of software development culture does not give a full picture, I argue that it nonetheless provides deep insights.     

A Lack of Insight: An Experimental Analysis of R&D Managers’ Decision Making in Innovation Portfolio Management

This study analyses the decision to exploit an innovation project and investigates differences in individuals’ evaluations of project attributes in the context of innovation project portfolio management. A conjoint field experiment was used to collect data on exploitation decisions made by 126 research and development (R&D) managers to test how managers evaluate specific project attributes in the context of innovation project portfolio management. I analyse the relative power and popularity of profitability, strategy, uncertainty and social dimensions of the portfolio while R&D managers exploit an innovation project. Moreover, using social judgement theory, I analyse actual exploitation processes (i.e., the innovation attributes an R&D manager considers while he or she is making an exploitation decision) and self‐reported decision‐making attributes (i.e., managers’ self‐reported data). The data underline that R&D managers value specific project attributes more and others less, and therefore find disparities in innovation project portfolio decision making. Based on this study's results, decision makers are better able to reflect and understand the influence of specific project attributes. Therefore, they should investigate established decision‐making processes which can help them to improve portfolio performance.     

B2B Procurement and Marketplace Transformation

Emerging web technologies and systems have started a revolutionary path that will have a profound impact on procurement processes and systems, especially in the area of indirect procurement and the management of operating resources. In fact, what started as more narrowly focused procurement systems only a couple of years ago, has transformed into a web of technologies, markets, and business strategies that have ramifications well beyond the purchasing function. The focus of this paper is on the marketplace structure, functionality and capabilities of systems, and key factors that buyers need to take into consideration when transforming their procurement processes. Contents management, markets, standards, and outsourcing are important problems that are discussed in this paper.