Sensing of silver ions by nanotubular polyaniline film deposited on quartz-crystal in a microbalance

Nanotubular polyaniline film was deposited onto the electrode of the quartz-crystal microbalance (QCM). The film in the form of emeraldine base was exposed to a solution of silver nitrate. The reduction for silver ions took place and silver nanoparticles were produced at the film surface. The deposition of silver was monitored by using the QCM and the UV–vis spectroscopy. The morphology of the film before and after the silver deposition was studied by the scanning and transmission electron microscopy. Silver nanoparticles had sizes of about 50–120 nm and globular and triangular shape. X-ray diffraction and infrared spectroscopy were used to characterize the structure of the composite. The present approach could be used for noble-metal recovery in waste waters.     

Business strategic conflict in computer-mediated communication

In this paper, we introduce the concept of business strategic conflict and examine its influence on communication media selection and use in inter-organisational collaborations. In doing so, we show the inherent complexities in the computer-mediated interactions between synergistic companies in the same industry. The work draws on a field study carried out for 5 months in a case of a product design collaboration between two large high-tech corporations in Taiwan and Korea. Findings show that at an early stage of the collaboration, the use of media has shifted substantially from FTF meetings to email, while it is also found that, due to the competitive nature of the inter-organisational collaboration involved, business strategic conflict significantly influences media selection and, in turn, it is influenced by the selected media. Our results contribute to media selection theories that have so far neglected the coopetitive inter-organisational environment.     

Sustainable nitrogen-doped carbonaceous materials from biomass derivatives

Nitrogen-doped carbons were produced using hydrothermal carbonization of nitrogen-containing carbohydrates under mild temperature (180 °C). The resulting materials contain significant amounts of nitrogen and display a high degree of aromatization. The nitrogen contents are also retained after further calcination at higher temperatures. All the resulting materials have been thoroughly characterized using X-ray photoelectron spectroscopy, solid state ¹⁵N and ¹³C-nuclear magnetic resonance, elemental chemical analysis, nitrogen adsorption, scanning and transmission electron microscopy. The nitrogen-doped materials proved to have superior performance with respect to their nitrogen-free counterparts in terms of electrical conductivity.     

Comparative study of Nd:YAG laser-induced breakdown spectroscopy and transversely excited atmospheric CO2 laser-induced gas plasma spectroscopy on chromated copper arsenate preservative-treated wood

Taking advantage of the specific characteristics of a transversely excited atmospheric (TEA) CO(2) laser, a sophisticated technique for the analysis of chromated copper arsenate (CCA) in wood samples has been developed. In this study, a CCA-treated wood sample with a dimension of 20 mm × 20 mm and a thickness of 2 mm was attached in contact to a nickel plate (20 mm × 20 mm × 0.15 mm), which functions as a subtarget. When the TEA CO(2) laser was successively irradiated onto the wood surface, a hole with a diameter of approximately 2.5 mm was produced inside the sample and the laser beam was directly impinged onto the metal subtarget. Strong and stable gas plasma with a very large diameter of approximately 10 mm was induced once the laser beam had directly struck the metal subtarget. This gas plasma then interacted with the fine particles of the sample inside the hole and finally the particles were effectively dissociated and excited in the gas plasma region. By using this technique, high precision and sensitive analysis of CCA-treated wood sample was realized. A linear calibration curve of Cr was successfully made using the CCA-treated wood sample. The detection limits of Cr, Cu, and As were estimated to be approximately 1, 2, and 15 mg/kg, respectively. In the case of standard LIBS using the Nd:YAG laser, the analytical intensities fluctuate and the detection limit was much lower at approximately one-tenth that of TEA CO(2) laser.     

A 25.5 MHz double-coaxial λ/4-resonator as a rebuncher in heavy ion linac system

A 25.5 MHz double-coaxial λ/4-resonator has been constructed to be used as a rebuncher between a 25.5 MHz RFQ linac and a 51 MHz interdigital-H linac for the acceleration of short-lived nuclei. By employing a double coaxial structure, the resonator length is only 130 cm; the length of the natural λ/4-resonator is 294 cm. The resonator, 69 cm in inner diameter, has six acceleration gaps. The bare shunt impedance is 40.6 MΩ/m. The ions with a charge-to-mass ratio 1/10 can be rebunched by feeding an rf power of 1.4 kW.     

Enacting new temporal boundaries: the role of mobile phones

This paper examines how the use of mobile phones influences the temporal boundaries that people enact in order to regulate and coordinate their work and non-work activities. We investigate both the structural and interpretive aspects of socio-temporal order, so as to gain a fuller appreciation of the changes induced by the use of mobile phones. With specific reference to professionals working in traditional, physically based and hierarchically structured organizations, we found that mobile phone users are becoming more vulnerable to organizational claims and that as a result ‘the office’ is always present as professionals, because of the use of mobile phones, become available ‘anytime’. This is enabled by the characteristics of the technology itself but also by users’ own behaviour. In the paper, we discuss the properties of the emerging socio-temporal order and show how mobile phones may render the management of the social spheres in which professionals participate more challenging.     

Possibility of a Chiral Phase Transition in Two-Dimensional 3He Solid

We study a Hamiltonian of S = 1/2 spins with two-, three and four-spin exchange interactions on the triangular lattice as a possible model of the nuclear magnetism of solid ³ He layers. The spin wave theory shows that the tetrahedral ground state, which was shown to be favoured by the four-spin exchange interaction in our previous paper, is stable against quantum fluctuations in some parameter region. Since this state has a scalar chiral long-range order, a phase transition occurs at a finite temperature even though the Hamiltonian has a full rotational symmetry in the spin space. Critical behavior of this phase transition was examined by classical Monte Carlo simulations. The specific heat diverges much more strongly than that of the 2D Ising model.     

Rapid exploration of unknown areas through dynamic deployment of mobile and stationary sensor nodes

When an emergency occurs within a building, it may be initially safer to send autonomous mobile nodes, instead of human responders, to explore the area and identify hazards and victims. Exploring all the area in the minimum amount of time and reporting back interesting findings to the human personnel outside the building is an essential part of rescue operations. Our assumptions are that the area map is unknown, there is no existing network infrastructure, long-range wireless communication is unreliable and nodes are not location-aware. We take into account these limitations, and propose an architecture consisting of both mobile nodes (robots, called agents) and stationary nodes (inexpensive smart devices, called tags). As agents enter the emergency area, they sprinkle tags within the space to label the environment with states. By reading and updating the state of the local tags, agents are able to coordinate indirectly with each other, without relying on direct agent-to-agent communication. In addition, tags wirelessly exchange local information with nearby tags to further assist agents in their exploration task. Our simulation results show that the proposed algorithm, which exploits both tag-to-tag and agent-to-tag communication, outperforms previous algorithms that rely only on agent-to-tag communication.     

Spatio-Temporal Modeling in Video and Multimedia Geographic Information Systems

The geographic application domain includes important information such as design plans, record drawings, photographs, and video data records. The corresponding geographic information systems (GISs) should maintain a specific model for each geographic data modality such as geographic video model for video records. Real-time 3-D geographic information systems provide comprehensive interface to complex and dynamic databases and truly immersive capability for visualizing geographic data. In cases, where information about location of geographic objects is needed at different moments of time, a GIS should process video data that is directly manipulated and retrieved through representation of its spatio-temporal characteristics. In this context, the most advanced multimedia form—digital video, finds an efficient application in GIS for versatile specification of geographic data. In this paper, a model for spatial data evolving with time is introduced in the context of video data manipulation. We designed a model that represents the spatio-temporal continuum among geographic objects in geographic video sequences, or digital video. The model developed here was motivated by the requirements for manipulating, managing, and analyzing geographic data for the necessities of infrastructure management, urban and regional planning, hazard prevention and management, transportation networks, vehicles routing, etc. This model allows the important issues for GIS such as conditions of adjacency (what is next to what), containment (what is enclosed by what), and proximity (how close one geographic object is to another) to be determined. Our model describes the spatial relationships among objects for each key frame in a given video scene, and the temporal relationships of the temporal intervals measuring the validity duration of the spatial relationships spanning over the given key frame. One of the main GIS issues—distance estimation, is solved as quantitative metrics of geographic objects in digital video are easily and precisely specified. This model is a basis for annotation of raw video for subsequent use in geographic video databases and digital libraries that provide access to and efficient storage of large volume of geographic data.     

Activation of Notch3 in Renal Tubular Cells Leads to Progressive Cystic Kidney Disease

Background: Polycystic kidney disease (PKD) is a genetic disorder affecting millions of people worldwide that is characterized by fluid-filled cysts and leads to end-stage renal disease (ESRD). The hallmarks of PKD are proliferation and dedifferentiation of tubular epithelial cells, cellular processes known to be regulated by Notch signaling. Methods: We found increased Notch3 expression in human PKD and renal cell carcinoma biopsies. To obtain insight into the underlying mechanisms and the functional consequences of this abnormal expression, we developed a transgenic mouse model with conditional overexpression of the intracellular Notch3 (ICN3) domain specifically in renal tubules. We evaluated the alterations in renal function (creatininemia, BUN) and structure (cysts, fibrosis, inflammation) and measured the expression of several genes involved in Notch signaling and the mechanisms of inflammation, proliferation, dedifferentiation, fibrosis, injury, apoptosis and regeneration. Results: After one month of ICN3 overexpression, kidneys were larger with tubules grossly enlarged in diameter, with cell hypertrophy and hyperplasia, exclusively in the outer stripe of the outer medulla. After three months, mice developed numerous cysts in proximal and distal tubules. The cysts had variable sizes and were lined with a single- or multilayered, flattened, cuboid or columnar epithelium. This resulted in epithelial hyperplasia, which was observed as protrusions into the cystic lumen in some of the renal cysts. The pre-cystic and cystic epithelium showed increased expression of cytoskeletal filaments and markers of epithelial injury and dedifferentiation. Additionally, the epithelium showed increased proliferation with an aberrant orientation of the mitotic spindle. These phenotypic tubular alterations led to progressive interstitial inflammation and fibrosis. Conclusions: In summary, Notch3 signaling promoted tubular cell proliferation, the alignment of cell division, dedifferentiation and hyperplasia, leading to cystic kidney diseases and pre-neoplastic lesions.