Biochemical machining — biochemical removal process of plastic

Plastic products are now ubiquitos; however, home and industrial plastic waste cannot be degraded. Hence, disposal of such wastes is now a large problem in maintining a clean environment. Some biodegradable plastics have been developed in response to demands for waste-free plastic products. Biodegradable Editorial Board plastics can be degraded by microorganism or enymes by means of cutting down the molecular chains. Taking note of the bio-degradation process of biodegradable plastic by microorganisms, biochemical machining, using a mold as a new biochemical microremoval process, has been developed.     

GC/MS with post-column switching for large volume injection of headspace samples: sensitive determination of volatile organic compounds in human whole blood and urine

When volatile or semivolatile compounds are measured by headspace (HS) gas chromatography (GC)/mass spectrometry (MS), the maximum gas volume to be injected is usually 0.5-1.0 mL; over the volume, the MS detector automatically shuts down due to impairment of the vacuum rate of the MS ionization chamber. To overcome the problem, we modified the gas flow routes of a new type of GC/MS instrument to create a postcolumn switching system, which can eliminate the large volume of gas before introduction of target compounds into the MS ionization chamber. Our HS-GC/MS system enabled injection of as large as 5 mL of HS gas without any disturbance. As the first example analysis, we tried to establish the analysis of naphthalene and p-dichlorobenzene in human whole blood and urine by this method with large volume injection. The limits of detection for both compounds in whole blood and urine were as low as about 10 and 5 pg/mL, respectively. The validation data and actual measurements were also demonstrated. The new GC/MS system has great potential to analyze any type of volatile or semivolatile organic compounds in biological matrixes with very high sensitivity and full automation.     

Ultracompact Asymmetric Mach–Zehnder Interferometers with High Visibility Constructed from Exciton Polariton Waveguides of Organic Dye Nanofibers

Manipulation of light using subwavelength waveguides is a key technology in the development of miniaturized photonic circuits, which possess various advantages over their electronic counterparts. The novel approach presented for such waveguiding involves the propagation of exciton polaritons (EPs), which are quasi‐particles formed by strong exciton–photon coupling, along organic dye nanofibers. A self‐assembled nanofiber of thiacyanine (TC) with a width of ≈200 nm propagates the EPs created by an optical excitation over a submillimeter‐scale distance and passes through a bend with a micrometer‐scale radius with low bending loss. To demonstrate the remarkable potential of EP‐based miniaturized photonic circuits, asymmetric Mach–Zehnder interferometers (AMZIs) are fabricated with TC nanofibers by micromanipulation. The AMZIs with a footprint of ≈20 μm × 20 μm exhibit a visibility of nearly unity and function as channel drop filters with the considerably high extinction ratio of up to ≈15 dB. Such high‐performance and ultracompact channel drop filters operating in the visible wavelength region have rarely been developed with other waveguide technologies. The coherent properties of the EPs in the nanofibers are investigated using time‐resolved experiments. The coherent properties provide useful information for designing EP‐based photonic circuits and for understanding EP dynamics in a nanofiber.     

Continuous Path Controller for the Remote Ultrasound Diagnostic System

A master-slave type remote ultrasound diagnostic system has been developed. The impedance controller has been implemented and reported for the positions of the master and slave manipulators to display and control the contact force between the ultrasound probe and the affected area. The present paper introduces an alternative orientation controller utilizing continuous path (CP) control in the remote ultrasound diagnostic system. The major contribution of the present paper is an introduction to the velocity-control-based CP controller for the master-slave type remote medical system, which realizes the continuous motion of the slave manipulator without a reduction in the master motion tracking performance. It is difficult to communicate information for control at high sampling rates between the master and slave site because the communication network between the master and slave site (local area network, integrated services digital network, asymmetric digital subscriber line, etc.) is limited. To cope with this problem, the CP controller was introduced to the orientation controller in special remote medical systems. The CP control realizes the continuous motion of the slave manipulator under the limited sampling rate of the orientation data transmitted by the master manipulator and high master motion tracking performance of the slave manipulator. This allows the slave manipulator safety to be improved and decreases the volume of the transmitted data. The experimental results demonstrate the accuracy of the path control of the slave manipulator using the CP control in the master--slave manipulation system, compared with the conventional point-to-point control.     

Antimicrobial resistance types and genes in Salmonella enterica infantis isolates from retail raw chicken meat and broiler chickens on farms

Salmonella enterica subsp. enterica serotype Infantis isolates from retail raw chicken meat (n = 98) and broiler chickens on farms (n = 70) were examined for antimicrobial susceptibility and antimicrobial resistance genes. A total of 15 antimicrobial resistance types, 14 in meat and 10 in broiler isolates, were identified, and 9 of the 15 types were indistinguishable between meat and broiler isolates. Resistance to both oxytetracycline and dihydrostreptomycin accounted for 94.0% of the resistance types in meat and broiler isolates, and each type harbored aadA1 within 1.0 kb of class 1 integron and tetA. Of nalidixic acid resistance types, point mutations at 87Asp (GAC) to Tyr (TAC) in the quinolone resistance-determining region of gyrA was detected in 10 of 13 meat isolates and at 87Asp to Asn (AAC) in four of seven broiler isolates. These findings suggest that the antimicrobial resistance of Salmonella Infantis in retail chicken meat predominantly originates from broiler chickens.     

Integration of a miniaturised triaxial force sensor in a minimally invasive surgical tool

This paper reports preliminary results on design and fabrication of a cutting tool with an integrated triaxial force sensor to be applied in fetal surgery procedures. The outer diameter of the proposed device is 7.4 mm, but a scaled down design can be easily achieved. Linearity and hysteresis tests have been performed for both normal and tangential loadings. A linear transformation relating the sensor output to the external applied force is introduced and discussed. The typical working range for the conceived instrument is around 0.3 N, while 20 N and 1 N are, respectively, maximum normal and tangential forces for which the device robustness has been assessed.     

Effect of soy peptide on brewing beer

Here, we examined the effect of soy peptides (SPs) on the fermentation and growth of Yeast Bank Weihenstephan 34/70 (W34/70), a bottom-fermenting yeast. We compared fermentation for SP with that for a free amino acid (FAA) mixture having the same amino acid composition as SP, as a nitrogen source. Maltose syrup was used as a carbon source, and the medium contained excess amounts of essential minerals and vitamins. We observed that SP was better than FAA mixture at promoting fermentation and growth and that much more beta-phenylethyl alcohol was produced during fermentation with SP than with FAA mixture. Subsequently, we compared fermentations with the FAA mixture and selected mixtures containing various dipeptides of Phe as a nitrogen source. We found that the rates of Phe metabolism and beta-phenylethyl alcohol generation were much higher when Phe was presented as a dipeptide (Phe-Asp, Phe-Leu, or Phe-Phe) than when presented as FAA. These results show that amino acids such as Phe are absorbed more rapidly when presented as a peptide than as FAA, resulting in a more rapid production of beta-phenylethyl alcohol.     

Porous plug and superfluid helium film flow suppressor for the soft X-ray spectrometer onboard Astro-H

Suppression of superfluid helium flow is critical for the Soft X-ray Spectrometer (SXS) onboard Astro-H, to achieve a life time of the liquid helium over 5 years. The superfluid film flow must be sufficiently small, compared to a nominal helium gas flow rate of the SXS . For this purpose, four devices composed of a porous plug, an orifice, a heat exchanger, and knife edge devices will be employed based on the experience of the X-ray microcalorimeter (XRS for X-Ray Spectrometer) onboard Suzaku. The porous plug is a phase separator of the liquid and gas helium. A potential film flow leaking from the porous plug is suppressed by the orifice. Almost all the remaining film flow evaporates at the heat exchanger. The knife edge devices stop the remaining film flow by using atomically sharp edges. In this paper, we describe the principle and design of these four devices.     

Effect of the molecular weight of poly(ethylene glycol), used for the surface treatment of calcium carbonate,on the tensile modulus of filled oriented polypropylene

A relation between tensile modulus of oriented polypropylene filled with calcium carbonate, and modified with poly(ethylene glycol) (PEG) or alkyl phenyl ether derivatives (APED) of different molecular weights was investigated. Upon stressing, voids appear in the composites material. For systems prepared with unmodified CaCO₃, the void volume increases with an increase of filler content. For systems containing modified CaCO₃, the void volume is smaller than the one of the reference material and decreases with an increase of PEG or APED molecular weights (which range from 400 to 4000 for PEG). Moreover, the relative modulus of oriented composites, E^d_c/E^d_r, are reasonably accounted by the void volume irrespective of filler content and modifier molecular weight, wherein E^d_c, E^d_r are respectively the modulus of oriented composites and the modulus of oriented polymer matrix.