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The aims of this study were to evaluate in vivo the biological responses to implants composed of biodegradable anodized WE43 (containing magnesium yttrium, rare earth elements and zirconium; Elektron SynerMag®) magnesium alloy, monolithic WE43 magnesium alloy and poly-l-lactic acid (PLLA), which are commonly used materials in clinic settings, and to evaluate the effectiveness of the materials as bone screws. The effectiveness of the magnesium alloy implants in osteosynthesis was evaluated using a bone fracture model involving the tibia of beagle dogs. For the monolithic WE43 implants, radiological, and histological evaluation revealed that bone trabeculae around the implanted monolithic WE43 decreased because of an inflammatory response. However, there was no damage due to hydrogen gas or inflammatory response in the bone tissue around the anodized WE43 implants. After 4 weeks, all the PLLA implants (n = 3) had broken but the WE43 implants had not (n = 6). These results suggest that the WE43 implants had sufficient strength to fix bone fractures at load-bearing sites in orthopedic and oral maxillofacial surgery. Therefore, these biodegradable magnesium alloys are good candidates for replacing biodegradable polymers. © 2015 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 104B: 1282-1289, 2016.

The aims of this study were to evaluate in vivo the biological responses to implants composed of biodegradable anodized WE43 (containing magnesium yttrium, rare earth elements and zirconium; Elektron SynerMag®) magnesium alloy, monolithic WE43 magnesium alloy and poly-l-lactic acid (PLLA), which are commonly used materials in clinic settings, and to evaluate the effectiveness of the materials as bone screws. The effectiveness of the magnesium alloy implants in osteosynthesis was evaluated using a bone fracture model involving the tibia of beagle dogs. For the monolithic WE43 implants, radiological, and histological evaluation revealed that bone trabeculae around the implanted monolithic WE43 decreased because of an inflammatory response. However, there was no damage due to hydrogen gas or inflammatory response in the bone tissue around the anodized WE43 implants. After 4 weeks, all the PLLA implants (n = 3) had broken but the WE43 implants had not (n = 6). These results suggest that the WE43 implants had sufficient strength to fix bone fractures at load-bearing sites in orthopedic and oral maxillofacial surgery. Therefore, these biodegradable magnesium alloys are good candidates for replacing biodegradable polymers. © 2015 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 104B: 1282-1289, 2016.

Alveolar bone resorption generally occurs during healing after tooth extraction. This study aimed to evaluate the effects of platelet-poor plasma (PPP), platelet-rich plasma (PRP), and platelet-rich fibrin (PRF) on healing in a ridge-augmentation model of the canine socket with dehiscence of the buccal wall. The third mandibular premolars of 12 beagle dogs were extracted and a 3 mm buccal dehiscence from the alveolar crest to the buccal wall of the extraction socket was created. These sockets were then divided into four groups on the basis of the material used to fill the sockets: PPP, PRP, PRF, and control (no graft material) groups. Results were evaluated at 4 and 8 weeks after surgery. The ultrastructural morphology and constructs of each blood product were studied by a scanning electron microscope (SEM) or calculating concentrations of platelets, fibrinogen, platelet-derived growth factor, and transforming growth factor-β. A total of five microcomputed tomography images of specimens were selected for measurement, and the area occupied by the newly formed bone as well as the horizontal bone width were measured. Moreover, decalcified tissue specimens from each defect were analyzed histologically. The median area of new bone at 4 and 8 weeks and median horizontal bone width at 8 weeks were the highest in the PPP group. However, bone maturation in the PRF and the PRP groups was more progressed than that in the PPP and control groups. By SEM findings, the PRF group showed a more highly condensed fibrin fiber network that was regularly arranged when compared with the PPP and PRP groups. The growth factors released from platelets in PRP indicated higher concentrations than that in PRF. Under more severe conditions for bone formation, as in this experiment, the growth factors released from platelets had a negative effect on bone formation. This study showed that PPP is an effective material for the preservation of sockets with buccal dehiscence.

We developed a 10 Gbps x 12 channel pluggable optical transceiver. It consists of three photoelectric devices, an FR4 substrate with a microcontroller, a 12 x 2 multimode fiber with three optical connectors for the three photoelectric devices, an electrical connector, and a heat sink. This transceiver can be vertically plugged to the motherboard by using electrical connector. A vertical plug enables the photoelectric conversion devices in the optical transceiver to be located close to the logic LSI on the motherboard at high density to prevent the waveform degrading. Moreover, it is possible to do prompt repairs if the transceiver breaks down because the module is pluggable. We demonstrated error-free operation after 50 m transmission over a GI/50 multimode fiber (MMF). These performance characteristics indicated that this optical transceiver is feasible for implementation in high- throughput interconnections.

A 400 Gbps backplane switch was developed with low-cost, small-size, 8-channels 10 Gbps/port optical I/O and a SiGe Bi-CMOS switch LSI on a 60x60-mm 2 BGA package. It indicates the applicability of backplane switch for high throughput backplane interconnections.

Summary form only given. In conclusion, a low crosstalk 8-channel optical transceiver was developed for star topology access networks for the first time. A receiver dynamic range of 21.6 dB and an allowable interchannel receiving power difference of 16.6 dB, both large enough for fiber in the loop (FITL) system with a serving area of 7.2 km, were obtained at 155 Mbit/s.

A 400 Gbit/s backplane switch was developed with a low-cost, small-size, 8-channel 10 Gbit/s/port optical I/O and a SiGe Bi-CMOS switch LSI on a 60/spl times/60-mm-square BGA package. It indicates the applicability of OIP for high throughput backplane interconnections.

There is a dilemma in choosing between high density packaging and low loss transmission line. Though the LSI circuit and packaging become high density, the wiring on the printed wire board (PWB) becomes wider over 10 Gbit transmission. This paper introduces opto-electronics packaging techniques which aims to solve the problem of optical interconnection dilemma.

Data-format-free operation is required for a multi-channel optical receiver array used in parallel optical links. A fixed decision threshold level scheme was applied to achieve a data-format-free receiver. However, it requires extremely high bandwidth, compared with the clock frequency for receivers, to obtain a large dynamic range and a wide eye opening, and to tolerate interchannel skew caused in optical fibers. Therefore, it seems to be difficult to achieve Gb/s class throughput with this scheme using low-cost technology. Using a decoder with AC receivers is one solution for obtaining data-format-free operation at narrower bandwidth, but this increases power dissipation. The receiver chip enables attainment of a Gb/s class data-format-free parallel optical receiver module suited for low cost packaging technologies with lower power consumption by utilizing automatic decision threshold control (ATC) which achieves response in one bit.

A data-format-free 622-Mbit/s/ch 12-channel optical transmitter and receiver have been developed. They provide a skewless PECL interface parallel link for 100-m transmission operating in the ambient temperature range from 0-70/spl deg/C with a 3.3 V power supply.

Eight-channel 1-Gbit/s array optical transmitter and receiver modules with 1.3-/spl mu/m wavelength have been developed using a passive-alignment assembly technology and one-chip transmitter and receiver LSIs, to achieve short-haul optical fiber interconnection cost effectively. It features a large dynamic range receiver that can tolerate the power fluctuation in low-cost adjustment-free transmitters and the loss deviation in cascaded optical connectors.

An optical interface is expected to solve the problems the electrical counterpart has. However, the conventional optical interface system using optical transceiver modules separately located from LSI packages on a printed circuit board (PCB), electrical interfaces among optical transceivers and LSI packages would limit interconnection speed. In addition, the electrical interface consumes a lot of power to drive the I/O buffers and signal lines on the PCB. To solve these problems, we have proposed a packaging technology to which OIP (Optical-interconnection as Intellectual Property) concept is applied. We developed a 3.125-Gbit/s/port crosspoint switch with 16 optical I/O ports on a 35x35-mm BGA package. It incorporates four small optical I/O modules called PETIT (Photonic/Electronic Tied InTerface).The PETIT consists of a 4-channel VCSEL array, a 4-channel pin-PD array, and a GaAs trans-impedance amplifier on an 8x8-mm ceramic substrate, and a newly developed optical connector interface is attached on the substrate. The sensitivity is 11.9 dBm under 12.5-Gbit/s full-duplex operation of the PETIT.