Development of a novel successive suturing instrument for an endoscope using beads and a side suction cap

The large number of patients who suffer from diseases such as gastritis, obesity, and chronic gastro-esophageal reflux disease has made the development of a new suture device using an endoscope instrument channel an important priority. This paper deals with a novel design of an endoscopic instrument that facilitates suture operations on the stomach and esophagus. Unlike a laparoscope, it is very difficult to transfer forces and moments to the end of a gastrointestinal endoscope from the outside handle dues to its extreme flexibility. The only feasible forces are pushing and pulling using wires and tubes. This new design requires only the push-pull action from the outside handle to complete suture operations. Furthermore, several stitches can be performed with a single endoscope insertion. This new endoscope suturing methodology thus significantly reduces the time for surgical operations and the pain that patients experience. The feasibility of the instrument was demonstrated through in vitro and in vivo animal experiments.     

Decentralized robust control for interconnected nonlinear systems

Decentralized robust control of strongly interconnected uncertain systems is addressed in this paper. The uncertainties we consider here may include parameter uncertainty and input disturbance that may be nonlinear and (possibly fast) time-varying. We show specially how both internal and external uncertainties are taken into considerations. This work covers a broad class of large-scale systems since the current consideration renders all previous settings as special cases. Stability analysis with the proposed controllers is provided.     

Adsorption equilibria for m-cresol,quinoline, and 1-naphthol onto silica gel

Adsorption isotherms for m-cresol, quinoline, and 1-naphthol onto silica gel in n-hexane at 30°C were measured in the concentration range of 1–30 mole/m³. The experimental results for m-cresol and quinoline were well represented by the generalized Toth isolherm, and for 1-naphthol by the superimposed two sites Langmuir model. At low concentrations the adsorbed amounts onto silica gel were decreased in sequence of quinoline, 1-naphthol, and m-cresol. However as the concentration increased, the sequence was reversed. For binary systems, the competitive adsorption was quantitatively studied by introducing the competitive adsorption coefficient. The relative affinity of quinoline with respect to silica surface was larger than those of the other two components.     

Novel Shorted Meander‐Line USB Dongle Antenna with a Compact Ground Plane

This letter presents the design of a novel multiband USB dongle antenna with a compact ground plane. The radiating patch is composed of a modified meander‐line monopole and a shorted loop to generate a dual‐broadband resonance. The proposed antenna supports WiBro, Bluetooth, WLAN, WiMAX, and S‐DMB services. The total dimensions of the fabricated antenna are 10 mm × 45 mm × 1 mm, the most compact size among multiband USB dongle antennas reported to date. The measured 10 dB reflection loss bandwidths are 20.8% (2.24 GHz to 2.76 GHz) and 20.2% (4.86 GHz to 5.95 GHz). The measured peak gain is 2.97 dBi, and efficiency is higher than 58%. In addition, the radiation pattern approximates an omnidirectional pattern.     

Physicochemical properties and oxidative stability of frying oils during repeated frying of potato chips

Physicochemical properties and oxidative stability of refined coconut oil (RCO), refined soybean oil (SBO), pure olive oil (POO), and vegetable shortening (VST) during repeated frying of potato chips were determined. Polyunsaturated fatty acids of all the oils significantly decreased after frying. Tocopherols in SBO, POO and VST, and DPPH radical scavenging activities of POO and VST significantly decreased after frying. L* values of the oils significantly decreased, and a* and b* values significantly increased after 80 times repeated frying. Conjugated dienes and p-anisidine value of SBO after 80 times repeated frying were 21.8 mmol/L and 47.7, respectively, the highest among the oils. Levels of total polar compounds of all the oils after 80 times repeated frying were between 8.1 and 9.5%, not exceeding rejection limit after frying. Compositions and contents of alkanals, 2-alkenals, and 2,4-alkadienals in the oils during frying were largely affected by their fatty acid compositions.     

Effects of roasting,powdering and storing irradiated soybeans on hydrocarbon detection for identifying post-irradiation of soybeans

Hydrocarbons, which are produced by irradiation of lipid-containing foods, were analyzed in irradiated soybeans, which were roasted, powdered and stored, to determine whether these treatments affect hydrocarbon detection for identifying post-irradiation of soybeans. Soybeans were irradiated (Irr), irradiated and roasted (Irr–Rst), roasted and irradiated (Rst–Irr), irradiated, roasted and powdered (Irr–Rst–Pwd), and roasted, powdered and irradiated (Rst–Pwd–Irr). They were stored at refrigerated or room temperature for 30 weeks. Oils were extracted using hexane and Na₂SO₄. Hydrocarbon fraction was separated through a Florisil column and analyzed using GC. Hydrocarbons 17:2, 16:3, 17:1 and 16:2 were not detected in non-irradiated soybeans and soybean powder, but they were detected in those irradiated at 0.5 kGy or higher. The levels of the hydrocarbons increased with dose. The hydrocarbon levels in the Irr–Rst, Rst–Irr, and Irr–Rst–Pwd soybeans were little different from those in the Irr soybeans. Hydrocarbon detection in the Rst–Pwd–Irr soybean powder showed a slightly different pattern from those in the other treatments. Hydrocarbon levels in the soybean and soybean powder samples stored at refrigerated temperature for 30 weeks changed little, compared to initial samples. The hydrocarbon detection patterns in the samples stored at room temperature for 30 weeks were similar to the initial and refrigerated samples with slightly lower detection levels in the room-stored samples.     

Enhancement in Organic Photovoltaic Efficiency through the Synergistic Interplay of Molecular Donor Hydrogen Bonding and π‐Stacking

For organic photovoltaic (OPV) cells based on the bulk heterojunction (BHJ) structure, it remains challenging to rationally control the degree of phase separation and percolation within blends of donors and acceptors to secure optimal charge separation and transport. Reported is a bottom‐up, supramolecular approach to BHJ OPVs wherein tailored hydrogen bonding (H‐bonding) interactions between π‐conjugated electron donor molecules encourage formation of vertically aligned donor π‐stacks while simultaneously suppressing lateral aggregation; the programmed arrangement facilitates fine mixing with fullerene acceptors and efficient charge transport. The approach is illustrated using conventional linear or branched quaterthiophene donor chromophores outfitted with terminal functional groups that are either capable or incapable of self‐complementary H‐bonding. When applied to OPVs, the H‐bond capable donors yield a twofold enhancement in power conversion efficiency relative to the comparator systems, with a maximum external quantum efficiency of 64%. H‐bond promoted assembly results in redshifted absorption (in neat films and donor:C₆₀ blends) and enhanced charge collection efficiency despite disparate donor chromophore structure. Both features positively impact photocurrent and fill factor in OPV devices. Film structural characterization by atomic force microscopy, transmission electron microscopy, and grazing incidence wide angle X‐ray scattering reveals a synergistic interplay of lateral H‐bonding interactions and vertical π‐stacking for directing the favorable morphology of the BHJ.     

Radioecological studies in Korea atomic energy research institute, KAERI

Regarding the assessment of the terrestrial food chain dose to man, radioecology may be the field that is focused on the transfer of radionuclides from environmental media to food crops. In Korea, the environmental transfer of radionuclides to staple food crops have been investigated at Korea Atomic Energy Research Institute (KAERI) for the last 25 y mainly through radiotracer experiments in greenhouses. As a result, several hundreds of parameter values for the prediction of the radionuclide transfer have been produced. Many of them appear in two recent publications of International Atomic Energy Agency. This paper outlines the KAERI's past radioecological work and introduces the ongoing research and future plans.     

Comments on “Comparison of diversity combining techniques forRayleigh-fading channels”

The authors comment that the probability density function (PDF) of the signal-to-noise ratio (SNR) for third-order selection combining (SC3) given by Eng, Kong and Milstein (see ibid., vol.44, p.1117-29, 1996) is incorrect. A correction is given by presenting a more efficient method of deriving the generalized PDF of the SNR essential in the analysis of Nth-order selection combining