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Wireless suspensions have been developed to improve the reliability of magnetic disk drives that use MR heads and pico-sliders. In this paper, we first consider what features are required for suspensions. We next investigate the characteristics in two types of wireless suspensions, a small two-piece suspension and a large conventional sized three-piece suspension. Finally, we demonstrate the advantages of the small two-piece suspension. Index Terms - Disk drive, HDI, shock, slider, stability, and suspension.

To achieve an ultralow flying height for magnetic heads, we developed a super proximity trapezoid shaped slider having leading edge width narrower than the trailing edge width. Compared to a conventional slider, it has lower inertia and mass and can maintain a higher roll stiffness. Therefore, it can reduce the impact force resulting from scattered projections on disk surfaces. In addition, it can reduce the flying height fluctuations due to slider rail irregularities, because it is supported at three points by air pressure. As a result, its flying stability is highly reliable.

An optimization method for magnetic disk drive suspensions that improves resonant frequencies in the access direction is described. The basic principles of this method are widening the node portions and narrowing the loop portions of a suspension in the sway mode. The frequency response characteristics were predicted with an precision analysis, which included deformation of the loaded suspension. These methods were applied to an integrated head suspension system, named pico-CAPS, We confirmed that the resonant frequency of the sway mode was higher than 10kHz, with an increase of 20%, and also confirmed the validity of these methods.

Ultralow load force pico-sliders must be reed to further improve the reliability of magnetic disk drives. We now propose a new integrated suspension for pico-sliders with MR heads, called pico-CAPS. The pico-CAPS features a monolithic body and has a direct signal pattern. It is light and has ultralow stiffness and a high resonant frequency. Our tests show that the pico-CAPS makes the flying pico-slider stable. Its shock resistance is high, and its electrical characteristics allow the high data transfer rate of over 40 MB/s.

Lateral and temporal profiles for concentrations of Cs and Cs were examined in marine sediments obtained from coastal and offshore areas on the Sea of Japan-side of central Honshu. In 2013, concentrations declined sharply from an estuarine (30 Bq/kg-dry for Cs) to offshore areas. In the offshore Sado Basin, the concentration of short-lived Cs, which was not detected (<0.3 Bq/kg-dry) in 2010, was 1-15 Bq/kg-dry in 2011-2013. Discharged riverine materials affected by radiocesium derived from the Fukushima Dai-ichi Nuclear Power Plant have been delivered to this offshore basin. [ABSTRACT FROM AUTHOR]

Radionuclide molecular imaging of cancer-specific targets is a promising method to identify patients for targeted antibody therapy. Radiolabeled full-length antibodies however suffer from slow clearance, resulting in high background radiation. To overcome this problem, a pretargeting system based on complementary peptide nucleic acid (PNA) probes has been investigated. The pretargeting relies on sequential injections of primary, PNA-tagged antibody and secondary, radiolabeled PNA probe, which are separated in time, to allow for clearance of non-bound primary agent. We now suggest to include a clearing agent (CA), designed for removal of primary tumor-targeting agent from the blood. The CA is based on the antibody cetuximab, which was conjugated to PNA and lactosaminated by reductive amination to improve hepatic clearance. The CA was evaluated in combination with PNA-labelled trastuzumab, T-ZHP1, for radionuclide HER2 pretargeting. Biodistribution studies in normal mice demonstrated that the CA cleared ca. 7 times more rapidly from blood than unmodified cetuximab. Injection of the CA 6 h post injection of the radiolabeled primary agent [ 131 I]I-T-ZHP1 gave a moderate reduction of the radioactivity concentration in the blood after 1 h from 8.5 ± 1.8 to 6.0 ± 0.4%ID/g. These proof-of-principle results could guide future development of a more efficient CA.

Combining immunotherapeutic and radiotherapeutic technique has recently attracted much attention for advancing cancer treatment. If boron-incorporated hemagglutinating virus of Japan-envelope (HVJ-E) having high membrane fusion ability can be used as a boron delivery agent in boron neutron capture therapy (BNCT), a radical synergistic improvement of boron accumulation efficiency into tumor cells and antitumor immunity may be induced. In this study, we aimed to develop novel boron-containing biocompatible polymers modified onto HVJ-E surfaces. The copolymer consisting of 2-methacryloyloxyethyl phosphorylcholine (MPC) and methacrylamide benzoxaborole (MAAmBO), poly[MPC- co -MAAmBO], was successfully synthesized by using a simple free radical polymerization. The molecular structures and molecular weight of the poly[MPC- co -MAAmBO] copolymer were characterized by nuclear magnetic resonance and matrix-assisted laser desorption ionization time-of-flight mass spectrometry, respectively. The poly[MPC- co -MAAmBO] was coated onto the HVJ-E surface via the chemical bonding between the MAAmBO moiety and the sugar moiety of HVJ-E. DLS, AFM, UV-Vis, and fluorescence measurements clarified that the size of the poly[MPC- co -MAAmBO]-coated HVJ-E, HVJ-E/p[MPC-MAAmBO], to be about 130 ~ 150 nm in diameter, and that the polymer having 9.82 × 10 6 ~ 7 boron atoms was steadily coated on a single HVJ-E particle. Moreover, cellular uptake of poly[MPC- co -MAAmBO] could be demonstrated without cytotoxicity, and the hemolysis could be successfully suppressed by 20%. These results indicate that the HVJ-E/p[MPC-MAAmBO] may be used as boron nanocarriers in a combination of immunotherapy with BNCT.

Development of new boron nanocarriers has been a crucial issue to be solved for advancing boron neutron capture therapy (BNCT) as an effective radiation treatment for cancers. The present study aimed to create a novel double-thermoresponsive boron-containing diblock copolymer based on poly( N -isopropylacrylamide) [poly(NIPAAm)], which exhibits two-step phase transitions (morphological transitions) at the temperature region below human body temperature. The boronated diblock copolymer considerably concentrates boron atoms into the water-dispersible (i.e., intravenous-administration possible) nanomicelles self-assembled by the first phase transition, and furthermore the properly controlled size and hydrophobicity of the second phase-transitioned nanoparticles are expected to make a significant contribution to the selective delivery and long-term retention of boron atoms into tumor tissues. Here we present the detailed synthesis of the strategic NIPAAm-based diblock copolymer with 3-acrylamidophenylboronic acid (PBA), i.e., poly(NIPAAm- block -NIPAAm- co -PBA), through a reversible addition-fragmentation chain transfer polymerization. Furthermore, the stepwise phase transition behavior of the obtained boronic-acid diblock copolymers was characterized in detail by temperature-variable ¹H and 11 B-nuclear magnetic resonance spectroscopy. The phase-transition-induced molecular structural changes, including the structural compositions and sizes of nanomicelles and nanoparticles, are also discussed here.

While the literature is rich with data for the electrical behavior of nanotransistors based on semiconductor nanowires and carbon nanotubes, few data are available for ultrascaled metal interconnects that will be demanded by these devices. Atomic layer deposition (ALD), which uses a sequence of self-limiting surface reactions to achieve high-quality nanolayers, provides an unique opportunity to study the limits of electrical and thermal conduction in metal interconnects. This work measures and interprets the electrical and thermal conductivities of free-standing platinum films of thickness 7.3, 9.8, and 12.1 nm in the temperature range from 50 to 320 K. Conductivity data for the 7.3 nm bridge are reduced by 77.8% (electrical) and 66.3% (thermal) compared to bulk values due to electron scattering at material and grain boundaries. The measurement results indicate that the contribution of phonon conduction is significant in the total thermal conductivity of the ALD films., (© 2012 American Chemical Society)