We retrospectively investigated the status of transfusional iron overload at Kinki University Hospital. One hundred and sixty three patients received more than 10 red blood cell (RBC) units per year in 2009 and 2010. Myelodysplastic syndrome (37.4%) and aplastic anemia (11.0%) accounted for about 50% of the underlying diseases. At the time of receiving a total of 20 RBC units, 90.8% and 66.2% of the 65 patients evaluated had more than 500 and 1,000 ng/ml of serum ferritin, respectively. The frequency of organ dysfunction associated with iron overload was 56.9% of all the patients assessed, 37.8% of patients with serum ferritin levels of 500∼999 ng/ml, and 67.4% of patients with serum ferritin levels >1,000 ng/ml. Although the Japanese guidelines propose 40 units of RBC transfusion and/or a serum ferritin level of 1,000 ng/ml as a good point to start iron chelation therapy, our results suggest that iron overload and consequent organ dysfunction may occur earlier than this. Therefore, it may be necessary to start iron chelation therapy earlier than that suggested by the Japanese guidelines.

同種輸血に伴う非溶血性副作用は比較的よくみられる副作用であるが, 本邦における実際の頻度は明らかではない. 今回, 近畿大学医学部附属病院における非溶血性副作用の頻度について検討した. 血小板製剤, 赤血球製剤および新鮮凍結血漿の輸血後の全体の非溶血性副作用の頻度は3.29%であった. 3つの製剤の中では血小板製剤が5.18%ともっとも高頻度であった. 血小板製剤を洗浄することによって非溶血性副作用の頻度が5.79%から0.29%と著明に減少した. 赤血球製剤の非溶血性副作用の頻度は2.43%であったが, 白血球除去フィルターの使用例や, 白血球除去赤血球製剤ではそれぞれ1.13%, 0.57%と副作用の頻度が低下した. 非溶血性副作用は比較的高頻度にみられ, その予防が重要と考えられた.

Synaptic connections are known to change dynamically. High-frequency presynaptic inputs induce decrease of synaptic weights. This process is known as short-term synaptic depression. The synaptic depression controls a gain for presynaptic inputs. However, it remains a controversial issue what are functional roles of this gain control. We propose a new hypothesis that one of the functional roles is to enlarge basins of attraction. To verify this hypothesis, we employ a binary discrete-time associative memory model which consists of excitatory and inhibitory neurons. It is known that the excitatory–inhibitory balance controls an overall activity of the network. The synaptic depression might incorporate an activity control mechanism. Using a mean-field theory and computer simulations, we find that the synaptic depression enlarges the basins at a small loading rate while the excitatory–inhibitory balance enlarges them at a large loading rate. Furthermore the synaptic depression does not affect the steady state...

Synaptic connections are known to change dynamically. High-frequency presynaptic inputs induce decrease of synaptic weights. This process is known as short-term synaptic depression. The synaptic depression controls a gain for presynaptic inputs. However, it remains a controversial issue what are functional roles of this gain control. We propose a new hypothesis that one of the functional roles is to enlarge basins of attraction. To verify this hypothesis, we employ a binary discrete-time associative memory model which consists of excitatory and inhibitory neurons. It is known that the excitatory-inhibitory balance controls an overall activity of the network. The synaptic depression might incorporate an activity control mechanism. Using a mean-field theory and computer simulations, we find that the basins of attraction are enlarged whereas the storage capacity does not change. Furthermore, the excitatory-inhibitory balance and the synaptic depression work cooperatively. This result suggests that the synaptic depression works to improve an error-correcting ability in cortical circuits.

To form large-grained polycrystalline-silicon (poly-Si) films on glass substrates, we propose a new lateral crystallization method, zone melting for film, which uses a high-power fundamental continuous wave yttrium aluminum garnet (CW-YAG) laser and an absorption layer. The laser's infrared light is changed into thermal energy at the absorption layer and heats the amorphous Si (a-Si) film. Next, the Si film is zone-melted and solidified in one direction with a scanning laser beam. By this method, columnar structured Si films were successfully formed with scanning velocities from 400 to 1000 mm/s. Very large typical grains of 1 or 2 µm by few hundreds of µm were obtained on both glass and quartz substrates, and the long axes of the grains were almost parallel to the laser scanning direction. Textures were also observed in these columnar structured Si films. Recombination carrier lifetimes of these films were several times longer than those of conventional low-temperature-processed poly-Si films.

Neurophysiological experiments show that synaptic depression controls a gain for presynaptic inputs. However, the functional roles of this gain control remain unknown. We propose that one of the functional roles is to enlarge basins of attraction. To verify this, we employ an associative memory model. An activity control is requisite for the stable retrieval of sparse patterns. We investigate a storage capacity and the basins of attraction. Consequently, the basins of attraction are enlarged while the storage capacity does not change. Thus, the synaptic depression might incorporate the activity control mechanism.

New planarization technology Of SiO2 films employing anhydrous HF (AHF) gas with no slurry was studied. In this planarization, the chemical reactions were dominant: consequently, soft planarization with no mechanical polishing was achieved. In this AHF planarization (AHFP) method, anisotropic etching Of SiO2 film using AHF gas, the so-called "Dry Ox Process" was applied. The Dry Ox Process was observed in a SiO2 surface covered with negative-tone-photo-resist in 1977. We accidentally found similar effects employing conventional positive-tone-photoresist (OFPR-800), and other types of resists. We applied the newly found condition to AHFP. Only the contact of OFPR film to the SiO2 film generated the condensed layer on the surface Of SiO2, consequently, initiation of AHFP was observed. However, the planarization process stopped within 1 min. This was considered that the active hydrogen on the surface of the OFPR was consumed. Eventually, the steps between the convexo-concave features were considerably reduced, improvement of film materials will be required for complete planarization.

CMP (Chemical mechanical Polishing) is currently used for the planarization of dielectric film in the ULSI multilayer metallization process. However, since CMP requires high loading pressure for a head, the planarization of a low-k porous silica film is not easy due to its fragile characteristic. In this paper, a new planarization method in which a SiO/sub 2/ film is polished softly has been proposed employing an anhydrous HF vapor.