The preclinical bioanalytical process with animal models begins with sampling biological fluids and tissue. The goal is to understand oral absorption kinetics, distribution, metabolism, excretion, blood brain barrier penetration, drug-drug interactions, and the influences on biomarkers, hematology, electrophysiology, cardiology, blood pressure and behavior. An overview is obtained by periodic blood sampling of 8 - 12 samples over a total time span of 10 - 24h. Urine, feces, bile and microdialysates can augment the information available from whole blood. In today’s preclinical environment, the majority of samples are processed by LC/MSMS augmented by robotic sample preparation tools. These tools save labor and improve precision for smaller volume/lower concentration samples. Our laboratories have been engaged in a project that is focused on improving both the quality and throughput for laboratory animal studies, while providing for reduced numbers of animals and enhanced animal comfort. We have implemented a robotic system that can accomplish most of the above goals for laboratory rats, dogs and primates. Studies with mice are at an earlier stage, but feasibility has been demonstrated. This presentation is a progress report on this evolving research program in cooperation with multiple pharmaceutical and drug development companies. We will illustrate results and discuss future directions.

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  This article reviews structural phase transitions of Zintl-phase silicide at high pressures and high temperatures and a formation of Si clathrate Ba₈Si₄₆ from an 8:30 molar mixture of and Si at high pressures and high temperatures. At pressures ranging from 0 to 10 GPa and temperatures ranging from 300 to 1300 K, has four phases: phase, EuGe₂ phase, SrSi₂ phase, and -IV phase. When heated at approximately 5 GPa, undergoes the three structural phase transitions: the -to-EuGe₂, the EuGe₂-to-SrSi₂, and the SrSi₂-to--IV transitions. At 4.3 GPa, Ba₈Si₄₆ is formed by a solid state reaction of an 8:30 molar mixture of SrSi₂-phase and Si after undergoes the -to-EuGe₂ and the EuGe₂-to-SrSi₂ transitions. The structural phase transitions of and formation process of Ba₈Si₄₆ are discussed comparing it with structural phase transitions of SrSi₂ and of an 8:30 mixture of SrSi₂-pahse SrSi₂ and Si.

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We investigated the surface potential distributions around grain boundaries (GBs) in phosphorus (P)-doped n-

thin-films by Kelvin probe force microscopy (KFM) and the crystal planes constituting GBs by transmission electron microscopy (TEM). By KFM measurements, it was found that the GBs in P-doped n- are different from those in undoped ; undoped n- has a downward band bending around the GBs with barrier heights of approximately 30 meV. In contrast, P-doped n- has an upward band bending with barrier heights of approximately 15 meV. TEM observation revealed that most of the GBs in P-doped are composed of (011)/() planes. This result is the same as that in undoped .

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has ideal optical properties for solar cell applications and can potentially realize solar cells with higher efficiency and lower cost than the mainstream crystalline Si solar cells. The close-spaced evaporation technique allows epitaxial growth of films on Si substrates with scalability to large areas. The technique itself and the properties of the films are reviewed in this article. Using a BaAl₄–Ni source ground in a mortar and pestle, films with (001) preferred orientation are grown on Si(100) at 1000℃. Such a high temperature growth leads to film cracking. Mechanical activation of BaAl₄–Ni by ball milling lowers the film formation temperature down to 700℃, resulting in crack-free films. The preferred orientation changes from (001) to (100). The crack-free films have low electron concentration around 10¹⁶ cm^－3 and show clear photoconduction, suggesting potential availability for solar cells.

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The authors tried to enhance the thermoelectric figure of merit of by doping La. Polycrystalline samples of La-doped : Ba_1−xLa_xSi₂ (0≤x≤0.08) were prepared and characterized. The effect of La-doping was investigated by measuring the thermoelectric properties above room temperature to 973 K. La could dissolve in up to around x=0.03, while LaSi₂ appeared as the second phase in the higher x range. Both the electrical resistivity and thermal conductivity of the La-doped samples were lower than those of the non-doped . Ba_1−xLa_xSi₂ (x=0.02) indicated the largest power factor and dimensionless figure of merit (ZT). The ZT value was 0.07 at 970 K, which was approximately 7 times larger than that of non-doped .

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This paper reviews structural phase transitions of at high pressures and high temperatures, and electrical resistivity measurements of two quenched high-pressure, high-temperature phases and a stable phase at ambient conditions. In situ x-ray diffraction measurements reveal that has three high pressure, high temperature phases: trigonal, cubic and an additional phase, at pressures up to 7 GPa and temperatures up to 1300 K. All of the high pressure, high temperature phases can be quenched at ambient conditions. The electrical resistivity measurements of trigonal, cubic and orthorhombic , a stable phase at ambient conditions, at 1 atm show that the electrical resistivity strongly depends on their crystal structure: orthorhombic and cubic are n-type semiconductors, and trigonal is a hole metal that shows superconductivity with an onset temperature of 6.8 K.

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We have realized single phase crystalline

thin films on quartz substrate by vacuum evaporation for solar cell applications. This structure is achieved by introducing (111)-oriented poly-Si fabricated by aluminum induced crystallization as a supply layer prior to deposition. Raman measurements showed five characteristic peaks corresponding to [Si₄]⁴⁻ anions vibrations in for all films deposited at 400 °C and above. X-ray diffraction analysis showed that randomly-oriented orthorhombic phase of is achieved with no trace of secondary phases. Also, the crystal quality is enhanced at higher substrate temperatures.

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We have grown undoped n-

epitaxial films with different grain sizes on Si(111) and characterized their minority-carrier lifetime, τ. We found that τ value in undoped n- did not depend on average grain area, but on surface condition. The samples with mirror surfaces had large τ of about 0.4 µs and those with cloudy surface small τ of about 8 µs. We tried to cap the sample surface in situ with a 3 nm Ba or Si layer in order to control the surface of , and succeeded to intentionally form with large τ.

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Es wurden die Systeme Silizium-Lithium, Silizium-Barium und Silizium-Strontium mit Hilfe der Gefügebeobachtung, röntgenographischen Untersuchung und thermischen Analyse untersucht und die Zustandsbilder aufgestellt. Übereinstimmend mit in bisherigen Literaturen angegebenen Ergebnissen wurden die Verbindungen Li₂Si, Li₄Si, , , SrSi und SrSi₂ bestätigt, während es sich für die Existenz der Verbindungen Li₃Si, , Ba₂Si₇ und keine Anzeichen ergaben. In diesen Systemen treten folgende nonvariante Dreiphasengleichgewichte auf:
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The B ion implantation to

films grown by molecular beam epitaxy was carried out to form p-type films. According to Raman spectra, post-annealing at over 600 °C for 64 min removed the ion-implantation damage. The hole concentration increased up to 3.1 × 10¹⁸ cm⁻³, which is applicable value to a hole transport layer. The B-ion-implanted p-/n-Si heterojunction solar cells exhibited the rectifying behavior in current-voltage curves under AM1.5 illumination and the internal quantum efficiency reached a maximum of 72% at a wavelength of 900 nm. The conversion efficiency was 2.2%. These results open new routes for the formation methods of solar cells.

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地球温暖化の影響から，枯渇する化石燃料を使用しない持続可能な再生可能エネルギーの重要性が再認識されている．太陽エネルギーを有効利用し発電する太陽電池は将来を期待されている再生可能エネルギー源の一つである．現在使用されている太陽電池の大部分を結晶Si太陽電池が占めているが，結晶Si太陽電池には二つの制限がある．一つは，Siのバンドギャップ（1.1 eV）が，単接合太陽電池が理論的最大変換効率（33.16%）を示す理想的なバンドギャップ（1.34 eV）より少し小さいことである．もう一つは，Siの光吸収係数αが小さいために光吸収層として150–250 μm程度の厚さが必要となるため，Siの消費量が多くなることである．これらの制限を克服するために，様々な物質を用いた薄膜太陽電池の作成が検討されてきた．薄膜太陽電池は，厚さが結晶Si電池の1/100程度であることから，省資源，大面積なものが容易に作成可，薄いためにフレキシブルになり用途が広がる，という利点を持つ．近年，高効率薄膜太陽電池材料としてバリウム・ダイシリサイド

が注目されている．は，（1）地殻埋蔵量の豊富な元素からなる（Si:地殻存在率第2位，Ba: 14位），（2）1.1～1.3 eVのバンドギャップを持つ，（3）バンドギャップ以上でαが急激に増加する，（4）少数キャリアの拡散長が長い，（5）不純物ドーピングによりn型，p型試料が作製できる，等の薄膜太陽電池材料として有望な性質を持っている．ホモ接合太陽電池のシミュレーションでは約25%の変換効率が得られている．結晶Si太陽電池，薄膜太陽電池（Cu（In, Ga）Se₂ ，CdTe，Cu₂ZnSn（S, Se）₄）の変換効率はそれぞれ26.7，21.7，21.5，12.6%であることから，太陽電池はこれらと同等またはそれ以上の変換効率を示すと期待できる．現在，p- /n-Siヘテロ接合太陽電池が作製され約10%の変換効率を示しているが，今後ホモ接合太陽電池の作製により更なる変換効率の向上が期待されている．

最近，我々は

が上記のような太陽電池材料として有望な性質を示す理由について第一原理計算を用いた考察を行った．このは4個のSi原子が四面体を作るという特徴的な結晶構造を持つ．無機化学でははジントル（Zintl）相として知られており，その結晶構造はジントル–クレム（Zintl–Klemm）則によって説明されている．それによると，Ba原子の二個の価電子がBa原子から二つのSi原子にそれぞれ1個づつ供給され，その結果，5個の価電子を持ったSi原子がオクテット則に従って三つのSi原子と結合していることによって，この結晶構造は実現されていると考えられている．我々は，BaからSiへの電荷移動，Si原子間共有結合の存在を確かめ，Zintl–Klemm則が成立していることを確かめた．また，の電子状態はSi₄四面体とBa原子の電子状態の重ね合わせで概ね理解できることを明らかにし，の分子軌道ダイヤグラムを構築した．の光吸収係数が間接遷移型半導体にも関わらず大きい理由は，間接遷移の0.1～0.3 eV上に複数の直接遷移が存在していることを明らかにした．更に，の主要な点欠陥であるSi空孔はバンドギャップ内に深い準位を作るがキャリアをトラップしにくいこと，固有欠陥がキャリアの生成には寄与せずpn接合の形成に必要不可欠な両極性ドーピングが可能であることを示した．

このように本研究では

が持つ幾つかの太陽電池材料として有望な物性の起源について明らかにした．今後，本研究の成果が，太陽電池の変換効率の向上の一助となること期待する．

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Eu²⁺-doped glasses were prepared by melting method and the glass-ceramics (GCs) were obtained by heat-treatment at various temperatures between 800 °C and 1000 °C. The single phase of micro-crystal precipitated in the GCs by heat-treatment above 950 °C, and the quantum yield (QY) of Eu²⁺ fluorescence became higher than that of other GCs, in which other crystal phases precipitated. When the precipitated, the QY increased drastically.

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半導体

は禁制帯幅が約1.3eVの半導体である．間接遷移型半導体であるが光吸収係数が大きく，また，多結晶膜であるが，結晶粒サイズよりも格段に大きな少数キャリヤ拡散長をもつなど，光キャリヤの生成と収集に特に有利な特徴をもつ．これは，結晶粒界が正に帯電し，少数キャリヤを結晶粒界から排斥する作用によると考えられる．本稿では，の少数キャリヤ特性を中心に，この材料の魅力と将来展望を述べる．

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Close-spaced evaporation (CSE) is a film deposition process that enables epitaxial growth and is scalable to large areas. Mechanical activation of the source by ball milling can extend the growth window in CSE of

down to 700 °C. However, the close arrangement of the powder source (BaAl₄–Ni) and the substrate might contaminate the films. This study investigated the structural and electrical properties of the films grown by CSE. It is found that the CSE films are not significantly contaminated by powder particles and Ni. In addition, semiconducting properties with low carrier density and high mobility are revealed by Hall effect measurement.

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フィリピンではバシ (甘薦酒) の発酵の際に樹皮類が添加されることから, 発酵過程における樹皮類添加の微生物の生育ならびにバシ成分への影響について検討した。酵母の生育に対しては樹皮類添加の影響はほとんどみられず, 発酵後のアルコール生成量に影響はみられなかった。しかし, 乳酸菌は樹皮類の添加により完全に生育を抑制され, バシの発酵では樹皮類の添加によって酸敗の原因となる乳酸菌の生育が抑えられることが確認された。また, 樹皮類を添加することによりそれらのポリフェノール成分が溶出して渋味を呈し, 原料糖の甘味が緩和されて飲みやすい味となったことから, バシの製造では渋味の付与も樹皮類添加の意義の一つであると考えられた。

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Proteomes of barley seeds were described by 2-D gel electrophoresis and spots selected for proteinidentification by mass spectrometry and database searches. Proteins were categorised according to temporalappearance during seed development and maturation. Fragments of β-amylases appeared transiently at midgrain filling and during germination. The α-amylase/trypsin inhibitors increased during grain filling andtypical housekeeping enzymes were present throughout the period. Germination altered the proteome and dissection of micromalted seeds enabled localization of selected proteins to specific tissues. The embryo was particularly rich in soluble proteins. Barley α-amylase/subtilisin inhibitor () and its target α-amylaseisozyme 2 occurred in endosperm and aleurone. Immunoblotting showed how the α-amylase changed duringgermination. Mutational analysis in a-amylase and was guided by the three-dimensional structures.Mutants along the 10 binding subsites in barley a-amylase 1 addressed roles of individual residues in thepreference for starch over oligosaccharide substrates and vice versa, action patterns on oligosaccharides, andmultiple attack on amylose. Although the wild-type enzyme was proficient in transglycosylation, mutants ofthe catalytic nucleophile did not act as glycosynthase. C-terminal fusion of a starch binding domain from Aspergillus niger glucoamylase to barley α-amylase isozyme 1 enhanced degradation of starch granules. Recent heterologous expression of allowed mutation of residues critical in enzyme binding as monitored by activity inhibition and surface plasmon resonance assays. A fully hydrated Ca²⁺ at the protein interface secured contact between and the catalytic residues in the α-amylase.

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To examine the plastic changes in orientation selectivity of developing visual cortex, we manipulated visual experience of kittens for 1-7 weeks under a freely moving condition, mounting cylindrical-lens-fitted goggles to present uni-axially elongated images of their environments, or spherical-lens-fitted goggles to present a stationary black-and-white oriented grating. We performed intrinsic signal optical imaging from those animals to reconstruct cortical representation of orientation preferences. For exposure to either a dynamic or stationary single orientation through the goggles, the extreme over-representation of exposed orientation was found in the visual cortex immediately after 1-2 weeks of continuous goggle rearing. For kittens exposed to a dynamic single orientation for a longer time, reorganized orientation maps were preserved although the degree of over-representation was somehow reduced. However, for kittens persistently exposed to a stationary oriented grating for long time, the over-representation effect almost disappeared or in some cases the orientation maps paradoxically exhibited the over-representation of the orientation orthogonal to the exposed orientation. It is suggested that the consolidation of reorganized orientation maps requires the experience of moving visual stimuli with behavioral relevance. [J Physiol Sci. 2006;56 Suppl:S60]

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Barium disilicide may be considered to be a promising material for solar cells. Thin films of

can be developed in various ways. In this paper, we discuss the properties of a barium silicide film obtained by a solid phase epitaxy. GIXRD method showed the presence of in the film which was obtained at the temperature T = 600, 750 and T = 800 °C. We hypothesize that the co-precipitation of Ba and Si can solve this problem and find that the increase of the annealing temperature results in better film crystallization (for the selected temperature).

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バリウムシリサイド（）は優れた薄膜太陽電池材料として期待されているが、その表面構造は十分に明らかになっていない。本研究では同軸型直衝突イオン散乱分光法 (CAICISS) を用いて、Si(111)上にエピタキシャル成長した薄膜の表面構造解析を行った。その結果、表面は60°ずつ回転した6つのドメインを形成し、再表面はSi原子で終端されていることを明らかにした。

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