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The purpose of our present study was to elucidate the involvement of the direct transfer to the brain after intranasal (i.n.) administration of diazepam (DZP), and to provide findings whether i.n. the administration could be used to obtain rapid onset of pharmacological action. We determined the blood and brain kinetics of DZP after administrations of i.n. and other routes, and the relationship between their concentrations and rapid seizure suppression effect; furthermore, and evaluated the distribution process of DZP to the brain. There was a negative connection between the plasma concentration and the amount of DZP delivery to the brain from the systemic circulation during the period that followed intravenous and intrarectal injection before the onset of seizure suppression. I.n. administration resulted in the seizure suppression time below the correlation curve: the seizure suppression effects were observed earlier than estimated despite the low plasma concentrations of DZP, suggesting the involvement of direct nose-to-brain delivery of DZP. The time to maximum concentration (Tmax) in the forebrain, hindbrain, olfactory bulb (OB), trigeminal nerve (TN), and cerebrospinal fluid (CSF) after i.n. the administration was 3 min, which was shorter than the Tmax of the plasma concentration. In fluorescence imaging using Rhodamin-B-base, the TN and the area of the vicinity of the thalamus had stronger fluorescence 1 and 3 min after i.n. administration, compared with the OB and CSF. In summary, direct brain delivery of DZP requires the TN and it was suggested that distribution to the vicinity of the thalamus via the TN may be connected to the quick seizure suppression effect., This is an open-access article distributed under the terms of the CC BY-NC 4.0 which permits unrestricted use, distribution, and reproduction in any medium for non-commercial use provided the original author and source are credited

収穫後青果物のエチレン処理が貯蔵中の高温耐性に及ぼす影響を議論するため，制御された環境で栽培されたリョクトウモヤシ葉部をエチレン処理した後に高温処理し，外観と生理的特性の変化を調べた．エチレン濃度50 ppmで3日間前処理すると，高温ストレス環境（50℃，120分）曝露後の葉部における壊死発生（外観品質の低下）の遅延と軽減が誘導された．さらに，エチレン処理することによって，50℃，60分の高温ストレス環境下におけるイオン漏出割合（イオンの膜透過性）の抑制が観察された．一方，呼吸速度や膜脂質の過酸化程度には，エチレン前処理の影響は見いだされなかった．これらの結果は，リョクトウモヤシに対する収穫後のエチレン処理によって，高温ストレス耐性が誘起されることを示しており，エチレンには高温障害に関連する膜損傷を軽減する作用があることが示唆された．以上の知見は，収穫後青果物の高温障害の抑制に対するエチレンの効用を検討することの重要性を示唆している．

Magnetic force microscopy (MFM) with a low moment probe and Q-control in a vacuum was applied to a permalloy semicircular wire loop with a single magnetic domain wall (DW). We successfully observed a nearly free single DW in such a nanomagnet, which is easy to move even using weak magnetic fields. In the case of MFM measurement with a high moment probe, the effects of the probe's stray field caused "DW manipulation," and the MFM signal was maximized just above the wire. When using the low moment probe, the MFM signal was maximized at the side of the wire, which concurs with the result of micromagnetic simulation.

We have developed a new scanning mode and an aligned carbon nanotube tip for atomic force microscopy (AFM) for measuring the critical dimension of deep structures. The aligned carbon nanotube (A-CNT) was assembled in the scanning electron microscope (SEM) chamber. The diameter of the tip is uniformly around 20 nm and the tip attachment angle is within ±1.5° to the sample normal. The aspect ratio (length/diameter) of the tip is greater than 30. The new scanning mode is composed of two functions, namely transporting the tip along the steep trench structure and detecting the sample surface. This mode can faithfully trace the steep side wall using a flexible CNT tip without damaging the tip. The critical dimension (CD) measurements of the shallow trench isolation (STI) were performed using the newly developed scanning mode and the A-CNT tip.

We have found an effective method for the evaluation of the crystal orientation of (K,Na)NbO3 (KNN) films in the (K,Na)NbO3/Pt/Ti/SiO2/Si structure using X-ray diffraction (XRD) reciprocal space maps. Previously, the crystal structure and orientation of such (K,Na)NbO3 films were evaluated using 2θ/θ XRD, and were considered to be the pseudocubic perovskite structure with preferential (001) orientation and no (111) orientation. Here, we applied the new method using XRD reciprocal space maps, and discovered that the (K,Na)NbO3 films had some degree of KNN(111) orientation. We calculated the KNN(001)- and KNN(111)-orientation volume fractions for the (K,Na)NbO3 films from the (101) diffraction peaks originating from the KNN(001)- and KNN(111)-orientation elements in the XRD reciprocal space maps, considering the calibration factors obtained from pole-figure simulations, and examined the relationship between the crystal orientation and d 31 piezoelectric coefficient in the (K,Na)NbO3 films. The results indicated that the d 31 piezoelectric coefficient increases with increasing (001)-orientation volume fraction.

We investigated the dry-etching characteristics of lead-free (K,Na)NbO3 (KNN) thin films by inductively coupled plasma-reactive ion etching (ICP-RIE) using Ar/C4F8 as the reactive gas mixture. The KNN etching depth showed a linear relationship as a function of the etching time with a few minutes' delay at the beginning. The etching rate increased with increasing antenna power and bias power. The antenna and bias dependences of the etching rate showed good linearity. The KNN/Pt selectivity increased with increasing antenna power and decreasing bias power. Thus, a high KNN/Pt selectivity was obtained under conditions of a high antenna power and a low bias power. The maximum KNN/Pt selectivity was 86. These etching results enable device fabrication using KNN thin films.

(K,Na)NbO3 (KNN) films with high transverse piezoelectric coefficients were successfully deposited onto Pt/Ti/SiO2/Si substrates by RF magnetron sputtering. These films were polycrystalline and had pseudo-cubic perovskite structures with preferential orientation. To improve their piezoelectric properties, we investigated the effects of annealing after the deposition and the Na/(K+ Na) ratio of the films. Annealing in air at 750 °C led to a decrease in the residual strain in the KNN crystal and the disappearance of openings at the grain boundary, thereby improving the transverse piezoelectric coefficient and leakage current properties. We also investigated the transverse piezoelectric coefficient and dielectric constant as a function of the Na/(K+ Na) ratio; both had maximum values at a ratio of approximately 0.55. For the KNN films, e 31 * ranged between -10.0 and -14.4 C/m2; thus, it was superior to previously reported values for lead-free piezoelectric films and was comparable to the best commercially available Pb(Zr,Ti)O3 films.

(K,Na)NbO3 (KNN) films with very high transverse piezoelectric coefficient d 31, which attained values comparable to those of Pb(Zr,Ti)O3 (PZT) films for the first time, were successfully deposited on Pt/Ti/SiO2/Si φ 4-in. substrates by RF magnetron sputtering. These films were polycrystalline and had pseudo-cubic perovskite structure with a preferred orientation. Furthermore, we focused on the effect of lattice strain on d 31 of KNN to clarify the relationship between the piezoelectric properties and structural parameters apart from orientation. We found that -d 31 increases with decreasing lattice strain c/a ratio of KNN when the in-plane lattice parameter a increases and the out-of-plane lattice parameter c decreases. By controlling the lattice strain c/a ratio strictly and maintaining a homogeneous strain, we achieved a high d 31 (∼-100 pm/V) that can be uniformized on φ 4-in. substrates and with a standard deviation that decreases to about 4 pm/V.

This article attempts to describe a novel high vacuum scanning force microscope (HV-SFM) using a self-oscillating piezoelectric cantilever in frequency modulation (FM) mode. Since no external deflection sensor or external vibrator is needed, the new HV-SFM is very simple and easy to handle in vacuum conditions in comparison with conventional systems using optical sensors. FM detection is used to detect the force gradient acting on the end of the piezoelectric cantilever because it gives higher response speed in vacuum conditions compared to the commonly used slope detection. The unimorph cantilever consists of a 1.0 μm thick Pb(Ti,Zr)O3 (PZT) layer on a SiO2 elastic base, which becomes self-oscillating when an ac voltage is applied to the piezoelectric layer. The 160 μm long piezoelectric cantilever has successfully been oscillated at its natural resonance frequency of 117 kHz by connecting its piezoelectric layer directly into the FM loop, which applies positive feedback to the piezoelectric charge curre...

The atomic image of 2H-NbSe2 surface was successfully recorded with a scanning tunneling microscope (STM) at room temperature. The trigonal pattern of the image is in good agreement with the results of the X-ray diffraction experiments. The STM apparatus developed here showed resolutions of 0.3 nm in the lateral scale and 0.05 nm in the vertical scale.

A novel high vacuum scanning force microscope (HV-SFM) using a piezoelectric cantilever and the phase detection method was developed. A self-excited force sensing PZT microcantilever with dimensions of 125×50×3.58 μm is vibrated in vacuum at its resonance frequency by applying an ac voltage to its PZT layer. The piezoelectric microcantilever possesses a spring constant of 16.7 N/m and a vibrational quality factor of 300 in air and 807 in vacuum. As we know, force gradients acting on the vibrating cantilever cause changes in vibration amplitude and phase. The change of the phase of the output piezoelectric current, which corresponds to the phase variation of cantilever vibration, is measured as the controlling signal in this method. The piezoelectric HV-SFM that was constructed has been proved to be stable and easy to handle in vacuum. Its vertical resolution is higher than 1.1 A. High resolution images of an evaporated Au film can be obtained in vacuum by this new dynamic HV-SFM. Grains of about 5 nm can ...

A scanning tunneling microscope (STM) with a capability of spectroscopic measurement for operation for 300 K to 1.2 K was constructed. Measurements of the current-voltage characteristics (I-V's) were performed on 2H-NbSe2 and a high-T c superconductor Y-Ba-Cu-O. Spatial variations in the local density of states (LDOS) relevant to the low temperature phases, CDW and superconductivity, were extracted from data statistics.

Anomalously large surface corrugation of 2H-NbSe2crystal was observed by scanning tunneling microscopy (STM). Besides mounds representing the Se atoms, hollow sites and Nb-atom sites clearly appeared as dips and saddle points, respectively. The lateral resolution was proved to be better than 0.2 nm. The large corrugation amplitude was attributed to the effect of atomic force between the tip and the sample.

Langmuir-Blodgett films of cadmium-arachidate have been studied by scanning tunneling microscopy (STM). Substrates of gold and graphite are used to make mono- and bilayer films. The image of the individual molecule cannot be obtained for the films on gold, but the data indicate disturbances on the tunneling current caused by the films. As for the films on graphite, the molecular images with a spacing of 0.4–0.7 nm are recognized in some frames of the variable tunneling current image recorded on videotape. Possible mechanisms of the imaging are discussed.