The characteristics of the external‐electrode mercury fluorescent lamp for backlighting liquid‐crystal‐television displays

Abstract— A reliable external‐electrode mercury fluorescent lamp (EEFL) has been developed for backlighting a liquid‐crystal‐television (LC‐TV) display. This involved the investigation of the EEFL characteristics and the improvement in the construction of the EEFL and drive waveforms, in the frequency range of 50–200 kHz, that affects the EEFL characteristics. The results showed that a sinusoidal waveform is suitable for driving the EEFL, and EEFL's voltage decreases when the frequency of the drive waveform is increased.     

Evaluation of Naturally Occurring HIF-1 Inhibitors for Pulmonary Arterial Hypertension

Pulmonary arterial hypertension (PAH) is a rare and severe progressive disorder characterized by high pulmonary artery pressure. Chronic hypoxia causes a metabolic disorder and the Warburg effect in pulmonary arterial smooth muscle cells (PASMCs). Pyruvate dehydrogenase kinase 1 (PDK1) is a key enzyme in Warburg effect increased by hypoxia-inducible factor (HIF-1). We constructed a cell-based luciferase assay system for HIF-1 inhibitors. Using this system, six HIF-1 inhibitors were identified. Among these inhibitors, the effect of tagitinin C ( 1 ) on PASMC was investigated. Tagitinin C ( 1 ) clearly decreased the amount of HIF-1β and the HIF-1 target PDK1. This result indicates that HIF-1 inhibitors effectively decrease PDK1 activity, which is a cause of the metabolic disorder and Warburg effect observed in PASMCs. Identifying naturally occurring HIF-1 inhibitors could provide novel insights into the development of PAH medications.     

Performance characteristics of a tower fermenter with mechanical foam control

For a bubble column (BC) treating foaming liquids, the characteristics of a rotating-disk mechanical foam-breaker (MFRD) fitted to the BC were examined. The foaming behaviour of the BC and the foam-breaking behaviour of the MFRD under various operating conditions were related to the changes in liquid hold-up in the foam. The gas hold-up in a mechanical foam-control system (MFS) with the MFRD was confirmed to be greater than the gas hold-up in a non-foaming system (NS) including antifoam agent (AF). Comparison of the volumetric mass transfer coefficient between the MFS and the non-foaming system, in terms of the specific power input, also demonstrated the superiority of mechanical foam control for oxygen transfer performance.     

A decentralized scheduling method for flowshop problems with resource constraints

In this paper, we propose a decentralized scheduling method for flowshop scheduling problems with resource constraints using the Lagrangian decomposition and coordination approach. When a flowshop scheduling problem with resource constraints is decomposed into machine‐level subproblems, the decomposed problem becomes very difficult to solve so as to obtain the optimal solution, even when the production sequence of operations is given. In this study, the decomposed subproblems are solved by a simulated annealing algorithm combined with dynamic programming. By decomposing the problem into single machine subproblems, the changeover cost can easily be incorporated in the objective function. In order to reduce the computation time, a heuristic algorithm for calculating the starting times of operations is also proposed. The performance of the proposed method is compared with that of the simulated annealing method by which the schedule of the entire machine is successively improved. Numerical results have shown that the proposed method can generate better solutions than the conventional method. © 2004 Wiley Periodicals, Inc. Electr Eng Jpn, 149(1): 44–51, 2004; Published online in Wiley InterScience ( www.interscience.wiley.com ). DOI 10.1002/eej.10364     

Synthetic fluid inclusion logging to measure temperatures and sample fluids in the Kakkonda geothermal field, Japan

Synthetic fluid inclusion logging is a new tool to measure temperatures and sample fluids in high-temperature geothermal wells. Fluid in the microcracks of a crystal can be trapped in inclusions through healing. Fluid inclusions in quartz, for example, can be synthesized easily in geothermal boreholes and can be used as long as the host crystal is stable (e.g. α-quartz is stable up to 573°C). This technique can be applied to high-temperature geothermal wells where conventional temperature measurement methods are not feasible. Cracked crystals of quartz, soaked in silica-saturated solutions in gold or platinum capsules mounted on containers, are placed in a geothermal borehole. Geothermal fluid enters the microcracks in the crystals at the selected sampling depths, and inclusions containing ambient fluid are formed through crack healing. Trapping temperatures of fluid inclusions in quartz are determined by microthermometry using a heating stage with pressure corrections. Other cracked crystals mounted in containers with rupture disks are used for fluid sampling. The first borehole experiment was conducted at WD-1, a deep research hole drilled in the Kakkonda geothermal field, northeast Japan, from September to October 1994 (24 days). Results from the experiment confirmed that temperatures measured from fluid inclusions are consistent with borehole temperatures measured by conventional logging tools.     

Three-dimensional display of X-ray CT image

Multi-slice images obtained by X-ray CT essentially have a three-dimensional data structure. They are useful for diagnosis and treatment through three-dimensional display. Surface display of organs is an effective three-dimensional display. However, although completely automatic processing of contour extraction is desirable it is also very difficult. For surface display, it is very important to extract contours of organs. Accordingly, using an interactive method, we have developed an algorithm for accurate three-dimensional display after extracting images of the cerebral ventricle. Satisfactory results have been obtained.     

A DNA Computing-based Genetic Program for In Vitro Protein Evolution via Constrained Pseudomodule Shuffling

An in vitro domainal shuffling strategy for protein evolution was proposed in (J. Kolkman and W. Stemmer, Nat. Biotech. 19 (423) 2001). Due to backhybridization, however this method appears unlikely to be an efficient means of iteratively generating massive libraries of combinatorially shuffled genes. Recombination at the domain level (30–300 residues) also appears too coarse to support the evolution of proteins with substantially new folds. In this work, the module (10–25 residues long) and pseudomodule are adopted as the fundamental units of protein structure. Each protein is modelled as an N to C-terminal tour of a digraph composed of pseudomodules. An in vitro method based on PNA-mediated Whiplash PCR (PWPCR), RNA-protein fusion, and restriction-based recombination, XWPCR is then presented for evolving proteins with a high affinity for a given motif, subject to the constraint that each corresponds to a walk on the pseudomodule digraph of interest. Simulations predict that PWPCR is an efficient method of producing massive, shuffled gene libraries encoding for proteins as long as roughly 600 residues.     

Fibrous hydroxyapatite grown in the gel system: effects of pH of the solution on the growth rate and morphology

In the preparation of fibrous hydroxyapatite (HAp), using the gel system consisting of agar gel containing calcium nitrate and over-layered (NH₄)₂HPO₄ solution, the pH of the solution was found to greatly influence the growth rate and morphology of the resultant products. In particular, a pH value of about 9–10 produced straight fibrous HAp in the shortest time. Also, the Ca/P molar ratio of the product increased with the pH value of the starting solution. The growth rate and morphology of the product were correlated to the ion species present in the solution at different pHs.     

Foam processing and cellular structure of polypropylene/clay nanocomposites

Polypropylene (PP)/clay nanocomposites (PPCNs) were autoclave‐foamed in a batch process. Foaming was performed using supercritical CO₂ at 10 MPa, within the temperature range from 130.6°C to 143.4°C, i.e., below the melting temperature of either PPCNs or maleic anhydride‐modified PP (PP‐MA) matrix without clay. The foamed PP‐MA and PPCN2 (prepared at 130.6°C and containing 2 wt% clay) show closed cell structures with pentagonal and/or hexagonal faces, while foams of PPCN4 and PPCN7.5 (prepared at 143.4°C, 4 and 7.5 wt% clay) had spherical cells. Scanning electron microscopy confirmed that foamed PPCNs had high cell density of 10⁷–10⁸ cells/mL, cell sizes in the range of 30–120 μm, cell wall thicknesses of 5–15 μm, and low densities of 0.05–0.3 g/mL. Interestingly, transmission electron microscopic observations of the PPCNs' cell structure showed biaxial flow‐induced alignment of clay particles along the cell boundary. In this paper, the correlation between foam structure and rheological properties of the PPCNs is also discussed.