ELECTROHYDRODYNAMIC CONVECTION IN PLANAR AND HOMEOTROPIC SYSTEMS OF NEMATIC LIQUID CRYSTALS(Session III : Complex Fluids, The 1st Tohwa University International Meeting on Statistical Physics Theories, Experiments and Computer Simulations)

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Oxalate Crystallization in the Kidney in the Presence of Hyperuricemia

It has been a long time since uric acid was suggested to be a promoting factor in calcium oxalate stones, and a number of in vitro studies have been carried out on the relationship between uric acid or urate and calcium oxalate. Concerning in vivo studies, urate or calcium oxalate stone-forming diets were given alone in most cases, and diets that induce formation of stones with different composition have not been given in combinations. We administered a low-concentration oxalemic diet, and a mixed diet containing oxalic acid and uric acid, and biochemically and histologically studied the effects of oxalate and uric acid on kidney stone formation. In the kidney of the animals given the mixed diet, formation of crystalloids of uric acid or urate was evident when no crystallization was noted in the kidney of those given the low concentration oxalemic diet alone. The morphological differences in the uric acid and urate crystalloids in the kidney and the process leading to crystallization of calcium oxalate were examined under transmission and scanning electron microscopy. Histological examination indicated that these uric acid crystals and urate crystals serve as seeds and induce formation and epitaxial growth of calcium oxalate crystals. Our in vivo study provides additional evidence that uric acid is a promoting factor in calcium oxalate stone formation

OCTAD-S: Digital Fast Fourier Transform Spectrometers by FPGA

We have developed a digital fast Fourier transform (FFT) spectrometer made of an analog-to-digital converter (ADC) and a field-programmable gate array (FPGA). The base instrument has independent ADC and FPGA modules, which allow us to implement different spectrometers in a relatively easy manner. Two types of spectrometers have been instrumented, one with 4.096 GS/s sampling speed and 2048 frequency channels and the other with 2.048 GS/s sampling speed and 32768 frequency channels. The signal processing in these spectrometers has no dead time and the accumulated spectra are recorded in external media every 8 ms. A direct sampling spectroscopy up to 8 GHz is achieved by a microwave track-and-hold circuit, which can reduce the analog receiver in front of the spectrometer. Highly stable spectroscopy with a wide dynamic range was demonstrated in a series of laboratory experiments and test observations of solar radio bursts.Comment: 20 pages, 7 figures, accepted for publication in Earth, Planets and Spac

Evaluating the Raftophilicity of Rhodopsin Photoreceptor in a Patterned Model Membrane

AbstractLipid rafts in the cell membrane are believed to affect various membrane functions, including the signaling by G-protein coupled receptors (GPCRs). However, the regulatory roles of lipid rafts on GPCRs’ functions are still poorly understood, partially owing to the lack of the methods to quantitatively evaluate the affinity of membrane proteins to lipid raft (raftophilicity). Here, we describe a methodology to gauge the raftophilicity of a representative GPCR in vertebrate photoreceptor, i.e., rhodopsin (Rh), and its cognate G protein transducin (Gt) by using a patterned model membrane. We generated a substrate-supported planar lipid bilayer that has patterned regions of liquid-ordered (Lo) and liquid-disordered (Ld) membrane domains. We reconstituted Rh and Gt into the patterned membrane and observed their lateral distribution and diffusion. Mobile and functional Rh molecules could be reconstituted through the rapid dilution of solubilized Rh, by optimizing the reconstitution conditions including the chamber design, protein/detergent concentrations, and solution mixing. We determined the partition and diffusion coefficients of Rh and Gt in the Lo-rich and Ld-rich regions. Both Rh and Gt were predominantly localized in the Ld phase, suggesting their low affinity to lipid rafts. Patterned model membrane offers a robust and scalable platform for systematically and quantitatively studying the functional roles of lipid rafts in biological membranes including retinal disk membranes

Cheek-splitting technique for marginal mandibulectomy : a novel approach

When performing marginal mandibulectomy, ensuring complete tumor removal and preventing postoperative iatrogenic mandibular fracture are essential. Pathological fracture can result due to stress concentration at the site requiring acute angle resection. To perform marginal mandibulectomy without making acute angles in patients with a lesion in the molar or more posterior region, a submandibular or transbuccal approach is necessary. Compared to the submandibular approach, the transbuccal approach is considered useful as it reduces operative time and prevents injury to the facial and mental nerves. Additionally, this approach does not leave a scar in the surgical field, which is beneficial in subsequent neck dissection for late neck metastasis. Here, we report 2 cases of lower gingival carcinoma in which satisfactory aesthetic outcomes were achieved with an improved cheek-splitting technique for marginal mandibulectomy using a transbuccal approach, taking into consideration the angle of the mouth, design of the triangular flap, and modiolus

Cell Type Specific Representation of Vibro-tactile Stimuli in the Mouse Primary Somatosensory Cortex

Although the processing of whisker deflections in the barrel area of the rodent primary somatosensory cortex (S1) has been studied extensively, how cutaneous vibro-tactile stimuli are processed in the rodent S1 outside the barrel area has not been fully examined. Particularly, the cell-type specific representation of multiple vibration frequencies in genetically identified inhibitory cells in the S1 has not been examined. Using two-photon calcium imaging, we examined the responses to vibration stimuli of excitatory and inhibitory neurons in the S1 hind limb area of male and female mice. The excitatory cells showed relatively sharp selectivity to vibration stimuli, whereas the inhibitory cells exhibited less selectivity. The excitatory and inhibitory cells with different preferred stimuli were intermingled in a “salt and pepper” manner. Furthermore, the noise correlation tended to be especially strong in excitatory-inhibitory and inhibitory-inhibitory cell pairs that have similar stimulus selectivity. These results suggest that excitatory cells tend to represent specific stimulus information and work together with similarly tuned inhibitory cells as a functionally connected network

光注入形ファイバレーザのコヒーレント光通信適用への基礎的研究

金沢大学工学部Erドープ光ファイバおよび励起半導体レーザ光源(0.98μmおよび1.48μm帯)を用いて、リング共振器形ファイバレーザを構成し、発振出力、発振波長および発振波長の可変特性を測定した。波長多重カップラによりErドープ光ファイバを励起した。リング共振器内のErドープ光ファイバには低濃度(高濃度)ドープ量Er:500ppm(9000ppm),光ファイバ長23.0m(1.4m),ループ長30.8m(8.8m),濃度条長積11.5kppm・m(12.7kppm・m)を用い、濃度の違いによるレーザ特性の変化を調べた(括弧内は高濃度の場合)。また分岐比可変カプラのにより種々の条件で発振特性を測定し、最適結合条件を求めた。次にファイバレーザの発振スペクトル線幅を遅延部分をループ状にした(ループ長80km)リング形遅延自己ヘテロダイン法により測定した。別の半導体レーザからファイバレーザに光注入する光注入同期発振器の可能性を調べた。さらにリング共振器はファイバフィルタとしても作用するので、その特性を調べた。以上の実験結果より次の結論を得た。(1)出力取り出しには最適条件があり、励起光強度35mWで、カプラの分岐比56.7%(77.3%)において最大出力2.4mW(2.1mW)を得た。(2)カプラの分岐比68.0%(88.8%)において最大スロープ効率8.9%(9.1%)を得た。(3)発振スペクトル線幅は3kHz(5kHz)であった。(4)光注入同期発振器として安定に動作するには極めて狭い外部光スペクトル線幅を必要とする。(5)信号光のコヒーレンス長よりループ長が長い本研究の光注入形ファイバレーザのリング共振器は励起光レベルによってピーク形からノッチ形まで特性可変の帯域フィルタとしても機能することが分かった。以上より一部改善すべき点があるが、光注入形ファイバレーザはコヒーレント光通信や光干渉計測への適用が有望であることを本研究結果は示している。We constituted two types of optical fiber ring lasers using Er-doped optical fibers (a low and a high Er-doping concentration) , which were pumped 980nm or 1480nm semiconductor laser diodes via a WDM optical fiber coupler, and measured the characteristics of the laser outputs, the lasing wavelengths, and the wavelength tuning. The laser outputs were obtained through an optical fiber coupler of which the coupling ratio was variable. In case of the low concentration, the Er-doped fiber length was 23.0m, the loop length 30.8m, and the concentration-length product 115.kppmm. When pumping power was 35mW and 56.7% coupling ratio, the maximum lasing output was 2.4mW.When the coupling ratio was 68.0%, the maximum slope efficiency was 8.9%. And the lasing spectral linewidth was measured as 3kHz using a 80km-ring version delayd self heterodyne method. In the hign concentration having the same concentration-length product of the low case, the maximum lasing output was 2.1mW at 35mW pumping and 77.3% coupling, the maximum slope efficiency was 9.1% at 88.8% coupling, and the lasing spectral linewidth was 5kHz. We also investigated an injection-locked fiber ring laser which was optically injected from a semiconducter laser diode. Resultingly, it was found that an extremely narrow linewidth of the master laser was needed for stable locked oscillations. In addition, we studied on use of out ring fiber confirulation as a ring fiber filter which acted as a pumping-power-controlable bandpass filter.研究課題/領域番号:05650349, 研究期間(年度):1993 – 1994出典：研究課題「光注入形ファイバレーザのコヒーレント光通信適用への基礎的研究」課題番号05650349（KAKEN：科学研究費助成事業データベース（国立情報学研究所）） （https://kaken.nii.ac.jp/ja/report/KAKENHI-PROJECT-05650349/056503491994kenkyu_seika_hokoku_gaiyo/）を加工して作

Leukemia autopsies in Japan

For the purpose to know whether the annual increase of leukemia incidence in Japan is due to some leukemogenic factors or due to the increased detection rate, the authors made some statistical survey of autopsy cases in which the diagnosis is reliable and not any type of leukemias escape the detection. The results showed that acute leukemias, which are found mostly in younger age, is actually increasing. In addition, it has been deduced that among the suspected factors the increase in ionizing radiation will be one of the most probable factors for the increase in leukemia incidence</p

Soft-mode turbulence in electrohydrodynamic convection of a homeotropically aligned nematic layer

The experimental study of electroconvection in a homeotropically aligned nematic ~MBBA! is reported. Thesystem undergoes a supercritical bifurcation ‘‘rest state-spatiotemporal chaos.’’ The chaos is caused by longwavelengthmodulation of the orientation of convective rolls. For the first time the observations both below andbeyond the Lifshitz point are accompanied by quantitative analysis of temporal autocorrelation functions ofturbulent modes. The dependence of the correlation time on the control parameter is obtained. A secondarybifurcation from normal to abnormal rolls is discussed