私たちは、超伝導膜を提供するためのバー・イラン大学からA. Sharoniに感謝します。本研究では、欧州研究評議会助成ERC-2014-STG- 639792によってサポートされていました、マリー・キュリーのキャリアの統合グラントFP7-PEOPLE-2012-CIG-333799、およびイスラエル科学財団助成ISF-1102から1113。

走査型SQUIDシステムへ1.アクセス<ol><li>チップ9、10、スティックスリップ粗動ステージ、および微動用ピエゾベースのスキャナ上に作製SQUIDセンサを含む走査型SQUIDシステムを使用してください。 図1を参照してください。 </li><li>ピックアップループのコーナーにSQUIDチップを磨きます。チップの材料はすべての方法のピックアップループに除去する必要があります。 <ol><li>ゆっくり5〜0.5μm程度の非磁性研磨紙を使用して、SQUIDを磨きます。 注：研磨ステージ後にピックアップループはサンプルで、近接、または接触させることができます。 </li></ol></li></ol>直流（DC）スパッタリング2.ニオブの堆積（NB）薄膜<ol><li>基板を得ました。この研究では、酸化ケイ素の500nmのホウ素ドープされたシリコン基板を用います。このようにSrTiOやMgOのような他の基板が可能です。 </li><li>ベースpressuに到達チャンバー内の10 -7 Torrの再。 10分間、1.8Å/秒の成膜速度で2.4トルの圧力でアルゴン環境下で、99.95％Nbターゲットを用いて室温での蒸発チャンバを予めスパッタ。チャンバ内のベース圧力が10未満-7トルである場合にのみ、堆積プロセスを開始できることに注意してください。圧力が高い場合、プリスパッタの段階を繰り返します。 </li><li>チャンバ内に基板を配置します。 </li><li> 1.8 A / Sの成膜速度で2.4トルの圧力でアルゴン環境で、99.95％Nbターゲットから室温でスパッタリングによりデポジットのNb薄膜。 </li></ol> 3.サンプルチップのアライメント<ol><li>渦を移動するときに、チップの先端が試料に接触するように、この段階では、試料とセンサチップを整列させます。これを達成するために、少なくとも4°の配向角を使用します。 </li><li>誘電体層と導電板上に柔軟なカンチレバーを接着。そして、SQUIDカイを接着カンチレバー上にp。カンチレバーと固定プレートとの間の静電容量は、サンプルと加えられる応力の程度との接触を決定します。 </li><li>顕微鏡の負荷サンプル。指定されたサンプルにサンプルを接着すると、ワニスまたは銀ペーストを使用してマウントします。 Zのピエゾ素子（ 図1a）にマウントを接着。 </li><li>コントローラにスティックスリップ粗動システムを接続します。 </li><li>フロントとチップの側面 - 二つの角度から光イメージングを設定します。チップとその辺の1の前面に向け並進ステージ上に配置された2つの望遠鏡を使用します。 </li><li> Zスティックスリップ粗動ステージを使用して、センサーの反射が試料上に表示されるように、センサーから1μmの距離にサンプルを移動させます。 注：この段階で、サンプルとセンサとの間の接触は、SQUIDを傷つけることがあります。 </li><li> Sへの損傷を防ぐために、Zスティックスリップ粗動ステージを使用して1ミリメートルセンサから離れ - 0.5のサンプルを動かしQUID。 </li><li>同じフロントの角度を取得するための位置合わせ用ネジ（ 図1a）を回転させる（ すなわち、 図1cに見られるように、チップの先端部の側面は、その反射で作る角度）。 </li><li>センサーから1μmの距離にサンプルを移動します。角度を確認し、必要に応じてステップ3.7と3.8を繰り返します。 </li><li>センサーおよびサンプル（ 図1D）との間に4度の角度を取得するために、位置合わせ用ネジを回します。チップの先端がサンプルと接触する部分であることを確認してください。 </li></ol> 4.測定<ol><li> 4 K冷却システムに走査ヘッド（ 図1a）をロードします。 注：スキャンヘッドは、コールドプレートに接続され、真空缶に囲まれるべきです。ワイヤー外部磁場を印加するための缶の周りにコイル（数ガウスの低フィールドは、この研究のために十分です）。ミューメタルシールドが、このセットアップをカバーしています。 </li><li>マグネの存在下でクールチックフィールド、顕微鏡を取り囲むコイルに電流を流すこともできます。所望の渦密度を達成するために慎重に電界強度を選択します。クールダウンフィールドを計算するために1Φ0 = 20.7 G /μmの2を使用してください。例えば、10μmのエリアによっては10μmで10渦のために、2.07 G.を適用</li><li>超伝導転移温度（10 K上のNbは、熱）上記新しい渦密度熱サンプルに変化させます。新しいフィールドを適用します。 </li><li> 4.2 Kにクールサンプル</li><li>磁場をオフにします。 SQUIDをオンにします。 </li><li>スティックスリップ粗動システムを使用して、SQUIDに近いサンプルを移動します。 <ol><li> SQUIDチップに近いサンプルを移動させるために、Z-スティックスリップキューブに増加電圧を印加します。 </li><li>キャパシタンスブリッジ（典型的には0.1〜1 V）を使用して容量を読み取るためのカンチレバーと板との間に電圧を印加します。 </li><li> Zピエゾ素子に電圧をスイープ。カンチレバーとプラットとの間の静電容量を測定します電子。静電容量の大きな変化が発生した場合、サンプルは、SQUIDチップと接触しています。 </li><li>サンプルがチップと接触していない場合は、手順を繰り返し4.6.1-4.6.3接触が観察されるまで。 </li><li>オプション：その連絡先は低電圧（0 - Zピエゾに適用される10 V）で行われるように、先端と試料との間の間隔を調整するために、コースの動きを使用してください。 </li><li>接触が、繰り返しは、表面の傾斜角を決定するためのセンサに対する試料の平面を定義するために、いくつかの場所に4.6.2-4.6.3ステップ。 </li></ol></li><li>センサに試料を相対的に移動させるためにX及びYピエゾ素子に電圧をスイープ。渦の分布をマッピングするために、チップと試料間の接触せずに、サンプル上記の一定の高さでスキャンします。 XとYの位置に応じたZピエゾの電圧を変化させることにより、および4.6で定義された平面に一定のスキャンの高さを実現。 </li><li>渦を選択し、arouスキャンNDは正確にその中心の位置を決定します。渦の場所がない接点に、SQUIDのピックアップループに対して相対的であることに注意してください。 </li><li> SQUIDをオフにします。 </li><li> Zピエゾへのタッチダウン電圧よりも高い電圧を印加し、いずれかの次の渦の中心部にタップするか、ゆっくりと目的の場所にサンプル上に（サンプルと接触して）センサーをドラッグすることで渦をスイープ。渦は、タップに向かってまたは掃引方向に移動します。適用されるのzピエゾ電圧に追加する典型的な値は2-5 Vです。 </li><li> SQUIDをオンにします。 </li><li>渦の新しい場所を見つけるために接触せずに一定の高さで、再び画像。 </li></ol>

<ol><li>Olson Reichhardt, C. J., Hastings, M. B. <a target="_blank" href="https://arxiv.org/abs/cond-mat/0307374">Do Vortices Entangle?</a> Phys. Rev. Lett. 92, 157002(2004).</li>
<li>Milošević, M. V., Berdiyorov, G. R., Peeters, F. M. <a target="_blank" href="http://pubs.acs.org/doi/abs/10.1021/nl301451e">Fluxonic cellular automata.</a> Appl. Phys. Lett. 91, 212501(2007).</li>
<li>Kalisky, B., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/pubmed?term=((Scanning+Probe+Manipulation+of+Magnetism+at+the+LaAlO3%2FSrTiO3+Heterointerface%5BTitle%5D)+AND+%22Nano+Lett%22%5BJournal%5D)">Scanning Probe Manipulation of Magnetism at the LaAlO3/SrTiO3 Heterointerface.</a> Nano Lett. 12, 4055-4059 (2012).</li>
<li>Silva, C. C. D. S., Van de Vondel, J., Morelle, M., Moshchalkov, V. V. <a target="_blank" href="http://www.nature.com/nature/journal/v440/n7084/full/nature04595.html">Controlled multiple reversals of a ratchet effect.</a> Nature. 440, 651-654 (2006).</li>
<li>Kalisky, B., et al. <a target="_blank" href="http://aip.scitation.org/doi/10.1063/1.3137164">Dynamics of single vortices in grain boundaries: I-V characteristics on the femtovolt scale.</a> Appl. Phys. Lett. 94, 202504(2009).</li>
<li>Embon, L., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/pubmed?term=((Probing+dynamics+and+pinning+of+single+vortices+in+superconductors+at+nanometer+scales%5BTitle%5D)+AND+%22Sci.+Rep%22%5BJournal%5D)">Probing dynamics and pinning of single vortices in superconductors at nanometer scales.</a> Sci. Rep. 5, 7598(2015).</li>
<li>Auslaender, O. M., et al. <a target="_blank" href="http://www.nature.com/nphys/journal/v5/n1/full/nphys1127.html">Mechanics of individual isolated vortices in a cuprate superconductor.</a> Nature Phys. 5, 35-39 (2008).</li>
<li>Kalisky, B., et al. <a target="_blank" href="https://arxiv.org/abs/1012.4271">Behavior of vortices near twin boundaries in underdoped Ba(Fe1-xCox)2As2.</a> Phys. Rev. B. 83, 064511(2011).</li>
<li>Huber, M. E., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/pubmed?term=((Gradiometric+micro-SQUID+susceptometer+for+scanning+measurements+of+mesoscopic+samples%5BTitle%5D)+AND+%22Rev.+Sci.+Instrum%22%5BJournal%5D)">Gradiometric micro-SQUID susceptometer for scanning measurements of mesoscopic samples.</a> Rev. Sci. Instrum. 79, 053704(2008).</li>
<li>Koshnick, N. C., et al. <a target="_blank" href="https://arxiv.org/abs/0901.0308">A terraced scanning super conducting quantum interference device susceptometer with submicron pickup loops.</a> Appl. Phys. Lett. 93, 243101(2008).</li>
<li>Kremen, A., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/pubmed?term=((Mechanical+Control+of+Individual+Superconducting+Vortices%5BTitle%5D)+AND+%22Nano+Lett%22%5BJournal%5D)">Mechanical Control of Individual Superconducting Vortices.</a> Nano Lett. 16, 1626-1630 (2016).</li>
</ol>

The authors have nothing to disclose.

渦の成功操作は、いくつかの重要なステップに依存します。チップの先端が試料と接触する第一となるように、角度センサを位置合わせすることが重要です。第二に、試料に加わる力は、チップがマウントされているカンチレバーの機械的特性によって決定されることに留意することが重要です。弾性政権では、加えられた力は、フックの法則によれば、たわみ、xに比例します。 F = -kx...

渦は、外部磁場の存在下で2型超伝導体で形成されたナノスケールでの磁性体です。欠陥のないサンプルでは、​​渦が自由に動くことができます。しかし、渦のためにエネルギー的に有利である縮小超伝導領域における材料の結果で異なる欠陥。渦はまた、ピン止め部位として知られ、これらの領域を飾るする傾向があります。この場合には、渦を移動させるために必要な力は、ピン止め力よりも大きくなければなりません。このような渦の濃度、相互作用の強さと範囲と渦の特性は、容易に外部磁界、温度、試料の形状によって決定されることができます。これらの特性を制御する能力は、それらを簡単に調整することができる凝縮物質の挙動のための良好なモデル系だけでなく、電子応用1、2のための適切な候補になります。個々の渦の位置の制御は、このようなLOの設計に不可欠です外科用要素。 磁性ナノ粒子の機械的な制御は、以前に達成されました。 Kalisky ら。最近複合酸化物界面3強磁性パッチのローカル機械的応力の影響を研究するために走査超電導量子干渉素子（SQUID）を使用しました。彼らは、プロセス中に1μNの力を加え、試料にSQUIDの先端を押し、接触して走査することにより、パッチの向きを変更することができました。私たちは、渦を移動させるために私たちのプロトコルに類似した方法を使用しています。 渦操作の既存の研究では、運動は、従って、ローレンツ力4、5、6を作成し 、サンプルに電流を印加することによって達成されました。この方法は有効であるが、それはローカルではなく、単一の渦を制御するために、追加の加工が必要となります。渦はまた、マニピュレータすることができます磁気力顕微鏡（MFM）またはSQUID磁場コイル7,8と、例えば、外部磁場を印加することによりulated。この方法は、効果的かつ局所的であるが、これらのツールによって加えられる力が小さく、唯一の超伝導体の臨界温度に近い高温でピン止め力を克服することができます。私たちのプロトコルは、サンプルの追加製作せずに低温（4 K）に効果的で、地元の操作を可能にします。 私たち走査型SQUID顕微鏡を用いた画像の渦。センサは、角に研磨、及びフレキシブルカンチレバー上に接着されたシリコンチップ上に製造されます。カンチレバーは、表面の静電容量センシングのために使用されます。接点は、チップの先端にあるように、チップは、試料に対して斜めに配置されています。私たちは、試料中にチップを押して、最大2μNの力を加えます。私たちは、ピエゾ素子によりSQUIDに対する試料を移動させます。私たちは移動します渦の隣に、または、それを掃引渦に触れることにより、シリコンチップをタップして渦。

<table><tbody><tr><td>stick slip coarse motion system</td><td>attocube</td><td>ANPx-101</td><td>x,y motion</td></tr><tr><td>stick slip coarse motion system</td><td>attocube</td><td>ANPz-101</td><td>z motion</td></tr><tr><td>stick slip coarse motion system controller</td><td>Attocube</td><td>ANC 300</td><td></td></tr><tr><td>high voltage amplifier</td><td>Attocube</td><td>ANC 250</td><td></td></tr><tr><td>data acquisition card</td><td>National Instruments</td><td>NI&amp;nbsp;PCIe-6363</td><td></td></tr><tr><td>piezo elements</td><td>Piezo Systems Inc</td><td>T2C</td><td>non magnetic</td></tr><tr><td>low noise voltage preamplifier</td><td>Stanford Research Systems</td><td>SR 560</td><td></td></tr><tr><td>capacitance bridge</td><td>General Radio</td><td>1615A</td><td></td></tr><tr><td>telescope</td><td>NAVITAR</td><td>1-504516</td><td></td></tr><tr><td>camera</td><td>MOTICAM</td><td>MP2</td><td></td></tr><tr><td>dewar</td><td>Cryofab</td><td>N/A</td><td></td></tr><tr><td>insert</td><td>ICE oxford</td><td>N/A</td><td></td></tr><tr><td>Mu-metal shield</td><td>Amuneal</td><td>N/A</td><td></td></tr><tr><td>vacuum cap</td><td>ICE oxford</td><td>N/A</td><td></td></tr><tr><td>sputtering system</td><td>AJA international Inc</td><td>N/A</td><td></td></tr><tr><td>lapping film</td><td>3M</td><td>261X</td><td>non magnetic</td></tr><tr><td>Nb target</td><td>Kurt J. Lesker</td><td>EJTNBXX351A2</td><td></td></tr><tr><td>GE Varnish</td><td>CMR-Direct</td><td>02-33-001</td><td>for cryogenic heatsinking</td></tr><tr><td>Silver paste</td><td>Structure Probe Inc</td><td>05063-AB</td><td></td></tr></tbody></table>

scanning squid study of vortex manipulation by local contact

Local, deterministic manipulation of individual vortices in type 2 superconductors is challenging. The ability to control the position of individual vortices is necessary in order to study how vortices interact with each other, with the lattice, and with other magnetic objects. Here, we present a protocol for vortex manipulation in thin superconducting films by local contact, without applying current or magnetic field. Vortices are imaged using a scanning superconducting quantum interference device (SQUID), and vertical stress is applied to the sample by pushing the tip of a silicon chip into the sample, using a piezoelectric element. Vortices are moved by tapping the sample or sweeping it with the silicon tip. Our method allows for effective manipulation of individual vortices, without damaging the film or affecting its topography. We demonstrate how vortices were relocated to distances of up to 0.8 mm. The vortices remained stable at their new location up to five days. With this method, we can control vortices and move them to form complex configurations. This technique for vortex manipulation could also be implemented in applications such as vortex based logic devices.

私たちのプロトコルが正常にNbを2サンプル、および窒化ニオブの9サンプル内の個々の、十分に分離渦の数千に試験しました。私たちは、Tcの上に試料を加熱し、磁場の存在下で4.2 Kに戻ってそれを冷却することによって、同じ試料上の新しい渦を発生させます。我々は、所望の渦密度を達成するために、外部磁界を選択しました。ここでは、これらの実験からのデー?...

Watch this Scientific Journal Video about Scanning SQUID Study of Vortex Manipulation by Local Contact at JoVE.com

Scanning SQUID Study of Vortex Manipulation by Local Contact

We present a protocol for manipulation of individual vortices in thin superconducting films, using local mechanical contact. The method does not include applying current, magnetic field or additional fabrication steps.

現地連絡先によって渦操作のSQUID研究をスキャンします

Local, deterministic manipulation of individual vortices in type 2 superconductors is challenging. The ability to control the position of individual ...

scanning-squid-study-of-vortex-manipulation-by-local-contact

Universidad San Sebastian

Research

JoVE Journal

Engineering

6.8K ビュー.  Bar-Ilan University. We present a protocol for manipulation of individual vortices in thin superconducting films, using local mechanical contact. The method does not include applying current, magnetic field or additional fabrication steps. 

ビデオ: Scanning SQUID Study of Vortex Manipulation by Local Contact

Quantitatively Measuring In situ Flows using a Self-Contained Underwater Velocimetry Apparatus (SCUVA)

The ability to directly measure velocity fields in a fluid environment is necessary to provide empirical data for studies in fields as diverse as oceanography, ecology, biology, and fluid mechanics. Field measurements introduce practical challenges such as environmental conditions, animal availability, and the need for field-compatible measurement techniques. To avoid these challenges, scientists typically use controlled laboratory environments to study animal-fluid interactions. However, it is reasonable to question whether one can extrapolate natural behavior (i.e., that which occurs in the field) from laboratory measurements. Therefore, in situ quantitative flow measurements are needed to accurately describe animal swimming in their natural environment.
We designed a self-contained, portable device that operates independent of any connection to the surface, and can provide quantitative measurements of the flow field surrounding an animal. This apparatus, a self-contained underwater velocimetry apparatus (SCUVA), can be operated by a single scuba diver in depths up to 40 m. Due to the added complexity inherent of field conditions, additional considerations and preparation are required when compared to laboratory measurements. These considerations include, but are not limited to, operator motion, predicting position of swimming targets, available natural suspended particulate, and orientation of SCUVA relative to the flow of interest. The following protocol is intended to address these common field challenges and to maximize measurement success.

Quantitatively Measuring In situ Flows using a Self-Contained Underwater Velocimetry Apparatus SCUVA

This protocol provides instructions on how to use a self-contained underwater velocimetry apparatus (SCUVA), which is designed for quantification of in situ animal-generated flows. In addition, this protocol addresses challenges posed by field conditions, and includes operator motion, predicting position of animals, and orientation of SCUVA.

定量的に測定その場で自己完結型水中速度計測装置（SCUVA）を使用してフロー

The ability to directly measure velocity fields in a fluid environment is necessary to provide empirical data for studies in fields as diverse as ...

生物工学

Quantitative and Qualitative Examination of Particle-particle Interactions Using Colloidal Probe Nanoscopy

Colloidal Probe Nanoscopy (CPN), the study of the nano-scale interactive forces between a specifically prepared colloidal probe and any chosen substrate using the Atomic Force Microscope (AFM), can provide key insights into physical interactions present within colloidal systems. Colloidal systems are widely existent in several applications including, pharmaceuticals, foods, paints, paper, soil and minerals, detergents, printing and much more.1-3 Furthermore, colloids can exist in many states such as emulsions, foams and suspensions. Using colloidal probe nanoscopy one can obtain key information on the adhesive properties, binding energies and even gain insight into the physical stability and coagulation kinetics of the colloids present within. Additionally, colloidal probe nanoscopy can be used with biological cells to aid in drug discovery and formulation development. In this paper we describe a method for conducting colloidal probe nanoscopy, discuss key factors that are important to consider during the measurement, and show that both quantitative and qualitative data that can be obtained from such measurements.

Colloidal probe nanoscopy can be used within a variety of fields to gain insight into the physical stability and coagulation kinetics of colloidal systems and aid in drug discovery and formulation sciences using biological systems. The method described within provides a quantitative and qualitative means to study such systems.

コロイドプローブナノスを使用して、粒子間相互作用の定量的および定性的調査

Colloidal Probe Nanoscopy (CPN), the study of the nano-scale interactive forces between a specifically prepared colloidal probe and any chosen substrate ...

化学

Visualization of High Speed Liquid Jet Impaction on a Moving Surface

Two apparatuses for examining liquid jet impingement on a high-speed moving surface are described: an air cannon device (for examining surface speeds between 0 and 25 m/sec) and a spinning disk device (for examining surface speeds between 15 and 100 m/sec). The air cannon linear traverse is a pneumatic energy-powered system that is designed to accelerate a metal rail surface mounted on top of a wooden projectile. A pressurized cylinder fitted with a solenoid valve rapidly releases pressurized air into the barrel, forcing the projectile down the cannon barrel. The projectile travels beneath a spray nozzle, which impinges a liquid jet onto its metal upper surface, and the projectile then hits a stopping mechanism. A camera records the jet impingement, and a pressure transducer records the spray nozzle backpressure. The spinning disk set-up consists of a steel disk that reaches speeds of 500 to 3,000 rpm via a variable frequency drive (VFD) motor. A spray system similar to that of the air cannon generates a liquid jet that impinges onto the spinning disc, and cameras placed at several optical access points record the jet impingement. Video recordings of jet impingement processes are recorded and examined to determine whether the outcome of impingement is splash, splatter, or deposition. The apparatuses are the first that involve the high speed impingement of low-Reynolds-number liquid jets on high speed moving surfaces. In addition to its rail industry applications, the described technique may be used for technical and industrial purposes such as steelmaking and may be relevant to high-speed 3D printing.

Two experimental devices for examining liquid jet impingement on a high-speed moving surface are described: an air cannon device and a spinning disk device. The apparatuses are used to determine optimal approaches to the application of liquid friction modifier (LFM) onto rail tracks for top-of-rail friction control.

表面移動に高速液体ジェット宿便の可視化

Two apparatuses for examining liquid jet impingement on a high-speed moving surface are described: an air cannon device (for examining surface speeds ...

工学

Methods for Measuring the Orientation and Rotation Rate of 3D-printed Particles in Turbulence

Experimental methods are presented for measuring the rotational and translational motion of anisotropic particles in turbulent fluid flows. 3D printing technology is used to fabricate particles with slender arms connected at a common center. Shapes explored are crosses (two perpendicular rods), jacks (three perpendicular rods), triads (three rods in triangular planar symmetry), and tetrads (four arms in tetrahedral symmetry). Methods for producing on the order of 10,000 fluorescently dyed particles are described. Time-resolved measurements of their orientation and solid-body rotation rate are obtained from four synchronized videos of their motion in a turbulent flow between oscillating grids with R&#955; = 91. In this relatively low-Reynolds number flow, the advected particles are small enough that they approximate ellipsoidal tracer particles. We present results of time-resolved 3D trajectories of position and orientation of the particles as well as measurements of their rotation rates.

We use 3D printing to fabricate anisotropic particles in the shapes of jacks, crosses, tetrads, and triads, whose alignments and rotations in turbulent fluid flow can be measured from multiple simultaneous video images.

乱流で3Dプリント粒子の配向および回転速度を測定するための方法

Experimental methods are presented for measuring the rotational and translational motion of anisotropic particles in turbulent fluid flows. 3D printing ...

Hand Controlled Manipulation of Single Molecules via a Scanning Probe Microscope with a 3D Virtual Reality Interface

Considering organic molecules as the functional building blocks of future nanoscale technology, the question of how to arrange and assemble such building blocks in a bottom-up approach is still open. The scanning probe microscope (SPM) could be a tool of choice; however, SPM-based manipulation was until recently limited to two dimensions (2D). Binding the SPM tip to a molecule at a well-defined position opens an opportunity of controlled manipulation in 3D space. Unfortunately, 3D manipulation is largely incompatible with the typical 2D-paradigm of viewing and generating SPM data on a computer. For intuitive and efficient manipulation we therefore couple a low-temperature non-contact atomic force/scanning tunneling microscope (LT NC-AFM/STM) to a motion capture system and fully immersive virtual reality goggles. This setup permits &#34;hand controlled manipulation&#34; (HCM), in which the SPM tip is moved according to the motion of the experimenter&#39;s hand, while the tip trajectories as well as the response of the SPM junction are visualized in 3D. HCM paves the way to the development of complex manipulation protocols, potentially leading to a better fundamental understanding of nanoscale interactions acting between molecules on surfaces. Here we describe the setup and the steps needed to achieve successful hand-controlled molecular manipulation within the virtual reality environment.

We demonstrate the precise manipulation of individual organic molecules on a metal surface with the tip of a scanning probe microscope driven in 3D by the experimenter's hand using a motion capture system and fully immersive virtual reality goggles.

3Dバーチャルリアリティのインターフェイスを持つ走査型プローブ顕微鏡を介した単一分子のハンド制御された操作

Considering organic molecules as the functional building blocks of future nanoscale technology, the question of how to arrange and assemble such building ...

Investigating the Three-dimensional Flow Separation Induced by a Model Vocal Fold Polyp

The fluid-structure energy exchange process for normal speech has been studied extensively, but it is not well understood for pathological conditions. Polyps and nodules, which are geometric abnormalities that form on the medial surface of the vocal folds, can disrupt vocal fold dynamics and thus can have devastating consequences on a patient&#39;s ability to communicate. Our laboratory has reported particle image velocimetry (PIV) measurements, within an investigation of a model polyp located on the medial surface of an in&#160;vitro driven vocal fold model, which show that such a geometric abnormality considerably disrupts the glottal jet behavior. This flow field adjustment is a likely reason for the severe degradation of the vocal quality in patients with polyps. A more complete understanding of the formation and propagation of vortical structures from a geometric protuberance, such as a vocal fold polyp, and the resulting influence on the aerodynamic loadings that drive the vocal fold dynamics, is necessary for advancing the treatment of this pathological condition. The present investigation concerns the three-dimensional flow separation induced by a wall-mounted prolate hemispheroid with a 2:1 aspect ratio in cross flow, i.e. a model vocal fold polyp, using an oil-film visualization technique. Unsteady, three-dimensional flow separation and its impact of the wall pressure loading are examined using skin friction line visualization and wall pressure measurements.

Vocal fold polyps can disrupt vocal fold dynamics and thus can have devastating consequences on a patient&#39;s ability to communicate. Three-dimensional flow separation induced by a wall-mounted model polyp and its impact on the wall pressure loading are examined using particle image velocimetry, skin friction line visualization, and wall pressure measurements.

モデルの声帯ポリープによる三次元流分離の調査

The fluid-structure energy exchange process for normal speech has been studied extensively, but it is not well understood for pathological conditions. ...

Visualization of Flow Field Around a Vibrating Pipeline Within an Equilibrium Scour Hole

An experimental method is presented in this paper to facilitate visualization of the detailed flow fields and determination of the near-boundary shear and normal stresses within an equilibrium scour hole induced by a vibrating pipeline. This method involves the implementation of a pipeline vibration system in a straight flume, a time-resolved particle image velocimetry (PIV) system for pipeline displacement tracking and flow fields measurements. The displacement time-series of the vibrating pipeline are obtained by using the cross-correlation algorithms. The steps for processing raw particle laden images obtained by using the time-resolved PIV are described. The detailed instantaneous flow fields around the vibrating pipeline at different vibrating phases are calculated by using a multiple-time-interval cross-correlation algorithm to avoid displacement bias error in the flow regions with a large velocity gradient. By applying the wavelet transform technique, the captured images that have the same vibrating phase are accurately cataloged before the phase-averaged velocity fields are obtained. The key advantages of the flow measurement technique described in this paper are that it has a very high temporal and spatial resolution and can be simultaneously used to obtain the pipeline dynamics, flow fields, and near-boundary flow stresses. By using this technique, more in-depth studies of the 2-dimensional flow field in a complex environment, such as that around a vibrating pipeline, can be conducted to better understand the associated sophisticated scour mechanism.

The goal of the protocol is to enable visualization of the detailed flow fields and determination of the near-boundary shear and normal stresses within an equilibrium scour hole induced by a vibrating pipeline.

平衡スカウトホール内の振動パイプライン周辺の流れ場の可視化

An experimental method is presented in this paper to facilitate visualization of the detailed flow fields and determination of the near-boundary shear and ...

環境学

Fabrication of Magnetic Nanostructures on Silicon Nitride Membranes for Magnetic Vortex Studies Using Transmission Microscopy Techniques

Electron and x-ray magnetic microscopies allow for high-resolution magnetic imaging down to tens of nanometers. However, the samples need to be prepared on transparent membranes which are very fragile and difficult to manipulate. We present processes for the fabrication of samples with magnetic micro- and nanostructures with spin configurations forming magnetic vortices suitable for Lorentz transmission electron microscopy and magnetic transmission x-ray microscopy studies. The samples are prepared on silicon nitride membranes and the fabrication consists of a spin coating, UV and electron-beam lithography, the chemical development of the resist, and the evaporation of the magnetic material followed by a lift-off process forming the final magnetic structures. The samples for the Lorentz transmission electron microscopy consist of magnetic nanodiscs prepared in a single lithography step. The samples for the magnetic x-ray transmission microscopy are used for time-resolved magnetization dynamic experiments, and magnetic nanodiscs are placed on a waveguide which is used for the generation of repeatable magnetic field pulses by passing an electric current through the waveguide. The waveguide is created in an extra lithography step.

A protocol for the fabrication of magnetic micro- and nanostructures with spin configurations forming magnetic vortices suitable for transmission electron microscopy (TEM) and magnetic transmission x-ray microscopy (MTXM) studies is presented.

磁気渦の研究伝達顕微鏡検査の技術を使用してシリコン窒化膜の磁性ナノ構造の作製

Electron and x-ray magnetic microscopies allow for high-resolution magnetic imaging down to tens of nanometers. However, the samples need to be prepared ...

In Vitro Reconstitution of Spatial Cell Contact Patterns with Isolated Caenorhabditis elegans Embryo Blastomeres and Adhesive Polystyrene Beads

In multicellular systems, individual cells are surrounded by the various physical and chemical cues coming from neighboring cells and the environment. This tissue complexity confounds the identification of causal link between extrinsic cues and cellular dynamics. A synthetically reconstituted multicellular system overcomes this problem by enabling researchers to test for a specific cue while eliminating others. Here, we present a method to reconstitute cell contact patterns with isolated Caenorhabditis elegans blastomere and adhesive polystyrene beads. The procedures involve eggshell removal, blastomere isolation by disrupting cell-cell adhesion, preparation of adhesive polystyrene beads, and reconstitution of cell-cell or cell-bead contact. Finally, we present the application of this method to investigate the orientation of cellular division axes that contributes to the regulation of spatial cellular patterning and cell fate specification in developing embryos. This robust, reproducible, and versatile in vitro method enables the study of direct relationships between spatial cell contact patterns and cellular responses.

In Vitro Reconstitution of Spatial Cell Contact Patterns with Isolated Caenorhabditis elegans Embryo Blastomeres and Adhesive Polystyrene Beads

Tissue complexities of multicellular systems confound the identification of causal relationship between extracellular cues and individual cellular behaviors. Here, we present a method to study the direct link between contact-dependent cues and division axes using C. elegans embryo blastomeres and adhesive polystyrene beads.

単離されたカエノラブディティス・エレガンス胚ブラストミアと接着剤ポリスチレンビーズを用いた空間細胞接触パターンのインビトロ再構成

In multicellular systems, individual cells are surrounded by the various physical and chemical cues coming from neighboring cells and the environment. ...

発生生物学

Visualizing Membrane Ruffle Formation using Scanning Electron Microscopy

Membrane ruffling is the formation of motile plasma membrane protrusions containing a meshwork of newly polymerized actin filaments. Membrane ruffles may form spontaneously or in response to growth factors, inflammatory cytokines, and phorbol esters. Some of the membrane protrusions may reorganize into circular membrane ruffles that fuse at their distal margins and form cups that close and separate into the cytoplasm as large, heterogeneous vacuoles called macropinosomes. During the process, ruffles trap extracellular fluid and solutes that internalize within macropinosomes. High-resolution scanning electron microscopy (SEM) is a commonly used imaging technique to visualize and quantify membrane ruffle formation, circular protrusions, and closed macropinocytic cups on the cell surface. The following protocol describes the cell culture conditions, stimulation of the membrane ruffle formation in vitro, and how to fix, dehydrate, and prepare cells for imaging using SEM. Quantification of membrane ruffling, data normalization, and stimulators and inhibitors of membrane ruffle formation are also described. This method can help answer key questions about the role of macropinocytosis in physiological and pathological processes, investigate new targets that regulate membrane ruffle formation, and identify yet uncharacterized physiological stimulators as well as novel pharmacological inhibitors of macropinocytosis.

Macropinocytosis is a highly conserved endocytic process initiated by the formation of F-actin-rich sheet-like membrane projections, also known as membrane ruffles. Increased rate of macropinocytotic solute internalization has been implicated in various pathological conditions. This protocol presents a method to quantify membrane ruffle formation in vitro using scanning electron microscopy.

走査型電子顕微鏡による膜ラッフル形成の可視化

Membrane ruffling is the formation of motile plasma membrane protrusions containing a meshwork of newly polymerized actin filaments. Membrane ruffles may ...