Evolution of supramolecular healable composites: a minireview

Efforts to further extend the range of applications of polymer based materials have resulted in the recent production of healable polymers that can regain their strength after damage. Within this field of healable materials, supramolecular polymers have been subject to extensive investigation. By virtue of their reversible non‐covalent interactions, cracks and fractures in such polymers can be readily and repeatedly healed in order to regain key physical properties. However, many supramolecular polymers are relatively weak and elastomeric in nature, which renders them unsuitable for high strength structural applications. To overcome these deficiencies, preliminary studies have shown that it is possible to reinforce supramolecular polymers with microscale and nanoscale fillers to afford composites that are not only stronger and stiffer compared with the polymers alone but also retain their healing abilities. In this minireview we discuss the evolution of these supramolecular composites and their advantages over more conventional, covalent polymeric materials. © 2014 Society of Chemical Industry     

Acute and sub-acute toxicity studies using Shemamruthaa,a modified indigenous Siddha preparation,in Sprague-Dawley rats

Shemamruthaa (SM), an indigenous herbal formulation (Hibiscus rosa sinensis flowers, Phyllanthus emblica, and pure honey) in a definite ratio was analyzed using acute and sub-acute toxicity studies in Sprague-Dawley rats. The acute toxicity study for 72 h showed no adverse effects in behavior or mortality at a dosage of 75–2,000 mg/kg of BW. The sub-acute toxicity study at 50, 100, 250, and 500 mg/kg of BW for 30 days showed transient rises in the white blood cell count, and levels of hemoglobin, free fatty acids, high density lipoproteins, and cholesterol, and a significant decrease in the blood glucose, cholesterol, triglyceride, phospholipid, and LDL levels. Other parameters remained unchanged. Changes observed were significant only at the highest dosage of 500 mg/kg BW. These results proved that the drug SM is safe and not toxic.     

A harmonic retrieval framework for discontinuous motion estimation

Motion discontinuities arise when there are occlusions or multiple moving objects in the scene that is imaged. Conventional regularization techniques use smoothness constraints but are not applicable to motion discontinuities. In this paper, we show that discontinuous (or multiple) motion estimation can be viewed as a multicomponent harmonic retrieval problem. From this viewpoint, a number of established techniques for harmonic retrieval ran be applied to solve the challenging problem of discontinuous (or multiple) motion. Compared with existing techniques, the resulting algorithm is not iterative, which not only implies computational efficiency but also obviates concerns regarding convergence or local minima. It also adds flexibility to spatio-temporal techniques which have suffered from lack of explicit modeling of discontinuous motion. Experimental verification of our framework on both synthetic data as well as real image data is provided.     

Estimating the viewing parameters of random, noisy projections ofasymmetric objects for tomographic reconstruction

The ability to determine the viewing parameters of objects from their projections has enabled well established tomographic techniques to be employed in the 3D reconstruction of objects from images obtained via modalities where the orientation of the objects cannot be controlled. A method is described for the determination of the viewing parameters of randomly acquired projections of asymmetric objects. It extends upon the common lines algorithm by determining the relative orientation of projections from the location of lines of intersection among the Fourier transforms of the projections in 3D Fourier space. A new technique for finding the lines of intersection in the presence of translational displacement, and for subsequently finding the translational displacement, is presented. The complete algorithm is described and its efficacy is demonstrated using real data. A new technique for dealing with noise is also discussed     

A machine vision system for enhancing the teleoperation of an industrial robot

This paper describes a real-time vision system that enhances the teleoperation of a servicing tool used in the heat exchangers of nuclear power plants. The vision system is used to track the position of the tool as it moves over a sheet of tube ends. A map-based strategy is adopted for the estimation of the position. The system incorporates a novel method for a foreshortening correction that is applied prior to map referencing. A hypothesize and verify scheme locates two image features that correspond to two map features. An efficient scheme for extracting image features is developed to locate these two features (tube-end centers) in the image. Two different types of heat-exchanger tube sheets are accounted for. They are those with tube ends placed in a square grid and those with tube ends placed in a triangular grid. The map-based strategy minimizes the cumulative errors in the estimate of the tool head position. The resulting low-cost system has been tested on synthetic and real data. Performance results are given.     

Organometallic L-Alanine Cadmium Iodide Crystals for Optical Device Fabrication

Single crystals of L-alanine cadmium iodide (LACI) were grown by the slow evaporation technique at room temperature. A single-crystal X-ray diffraction (SXRD) model was used to evaluate the crystal structure of the as-grown LACI crystal. The energy dispersive X-ray (EDX) analysis and ultraviolet-visible-near infrared (UV-vis-NIR) transmittance studies were carried out, and the results reveal the presence of elements in the title compound. From the transmittance data, the optical bandgap as a function of photon energy was estimated, and the different optical constants were calculated. A fluorescence study was performed for the LACI crystal. Thermogravimetric and differential thermal analyses have also been studied to investigate the thermal property of the LACI crystal. The efficiency of the second harmonic generation (SHG) of the title crystal was investigated. The magnetic and electrical properties were estimated by the vibrating sample magnetometer (VSM) analysis and impedance study, respectively.     

Unsupervised deep learning approach for network intrusion detection combining convolutional autoencoder and one-class SVM

Applied Intelligence - With the rapid advancement in network technologies, the need for cybersecurity has gained increasing momentum in recent years. As a primary defense mechanism, an intrusion...     

Cross-cultural IS adoption in multinational corporations: A study of rationality

A common claim in the literature on Information Systems' implementation in the context of less developed economies or so-called “developing countries” is that the “Western” technology is at odds with the local cultural context, in particular it is believed to mismatch local rationality in the sense of the accepted ways of doing things. In this paper we investigate IS implementation in a company based in a “non-Western” context compared with IS adoption in another company in a “Western” country context. Seen as a particular form of decision-making, the adoption and implementation processes are analysed drawing on the literature on decision-making, rationality in “Western” and “non-Western” contexts. Presenting evidence from these two contexts we argue that multiple forms of rationality exist in any context and that national culture is only one aspect of actors' as well as researchers' sense-making of activities in any given context. Linking the cases back the literature we reflect on the implications of our findings for cross-cultural research of IT implementation.     

Fabrication of Biogenic Silica Nanostructures from Sorghum bicolor Leaves for Food Industry Applications

Silicon - Due to the large production of sorghum, the generation of associated agricultural residues, which contain high contents of silica, is inevitable. Also, these agricultural residues are not...     

Natural rubber latex/potato starch nanocrystal nanocomposites: Correlation morphology/electrical properties

This paper discusses the preparation and characterization of nanocomposites obtained with potato starch nanocrystals, and their use as fillers in order to realize nanocomposites with a natural rubber latex matrix. The preparation of potato starch nanocrystals was done by hydrolysis of potato starch powder using sulfuric acid. The synthesized potato starch nanocrystal suspensions were mixed with natural rubber latex by latex stage mixing process using a magnetic stirrer. In this way, composites containing up to 20% w/w of fillers have been obtained. Morphological studies indicated a relatively uniform dispersion of starch nanocrystals in the nanocomposites until 15% w/w filler loading. Dielectric measurements confirm the existence of a threshold at a composition close to 15% w/w of filler at which the fillers become agglomerated.