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Drying of complex suspensions [article]

Lei Xu, Alexis Bergés, Peter J. Lu, André R. Studart, Andrew B. Schofield, Hidekazu Oki, Simon Davies, David A. Weitz
2010 arXiv   pre-print
We investigate the 3D structure and drying dynamics of complex mixtures of emulsion droplets and colloidal particles, using confocal microscopy. Air invades and rapidly collapses large emulsion droplets, forcing their contents into the surrounding porous particle pack at a rate proportional to the square of the droplet radius. By contrast, small droplets do not collapse, but remain intact and are merely deformed. A simple model coupling the Laplace pressure to Darcy's law correctly estimates
more » ... h the threshold radius separating these two behaviors, and the rate of large-droplet evacuation. Finally, we use these systems to make novel hierarchical structures.
arXiv:1003.6008v1 fatcat:a6ifzgpmgnhytlbi5ac72kniba

Energy-efficient computing for wildlife tracking

Philo Juang, Hidekazu Oki, Yong Wang, Margaret Martonosi, Li Shiuan Peh, Daniel Rubenstein
2002 SIGPLAN notices  
Over the past decade, mobile computing and wireless communication have become increasingly important drivers of many new computing applications. The field of wireless sensor networks particularly focuses on applications involving autonomous use of compute, sensing, and wireless communication devices for both scientific and commercial purposes. This paper examines the research decisions and design tradeoffs that arise when applying wireless peer-to-peer networking techniques in a mobile sensor
more » ... twork designed to support wildlife tracking for biology research. The ZebraNet system includes custom tracking collars (nodes) carried by animals under study across a large, wild area; the collars operate as a peer-to-peer network to deliver logged data back to researchers. The collars include global positioning system (GPS), Flash memory, wireless transceivers, and a small CPU; essentially each node is a small, wireless computing device. Since there is no cellular service or broadcast communication covering the region where animals are studied, ad hoc, peer-to-peer routing is needed. Although numerous ad hoc protocols exist, additional challenges arise because the researchers themselves are mobile and thus there is no fixed base station towards which to aim data. Overall, our goal is to use the least energy, storage, and other resources necessary to maintain a reliable system with a very high 'data homing' success rate. We plan to deploy a 30-node ZebraNet system at the Mpala Research Centre in central Kenya. More broadly, we believe that the domain-centric protocols and energy tradeoffs presented here for ZebraNet will have general applicability in other wireless azld sensor applications.
doi:10.1145/605432.605408 fatcat:6n4bwvnpivci7mf4kuxqtnt6vy

Energy-efficient computing for wildlife tracking

Philo Juang, Hidekazu Oki, Yong Wang, Margaret Martonosi, Li Shiuan Peh, Daniel Rubenstein
2002 SIGARCH Computer Architecture News  
Over the past decade, mobile computing and wireless communication have become increasingly important drivers of many new computing applications. The field of wireless sensor networks particularly focuses on applications involving autonomous use of compute, sensing, and wireless communication devices for both scientific and commercial purposes. This paper examines the research decisions and design tradeoffs that arise when applying wireless peer-to-peer networking techniques in a mobile sensor
more » ... twork designed to support wildlife tracking for biology research. The ZebraNet system includes custom tracking collars (nodes) carried by animals under study across a large, wild area; the collars operate as a peer-to-peer network to deliver logged data back to researchers. The collars include global positioning system (GPS), Flash memory, wireless transceivers, and a small CPU; essentially each node is a small, wireless computing device. Since there is no cellular service or broadcast communication covering the region where animals are studied, ad hoc, peer-to-peer routing is needed. Although numerous ad hoc protocols exist, additional challenges arise because the researchers themselves are mobile and thus there is no fixed base station towards which to aim data. Overall, our goal is to use the least energy, storage, and other resources necessary to maintain a reliable system with a very high 'data homing' success rate. We plan to deploy a 30-node ZebraNet system at the Mpala Research Centre in central Kenya. More broadly, we believe that the domain-centric protocols and energy tradeoffs presented here for ZebraNet will have general applicability in other wireless azld sensor applications.
doi:10.1145/635506.605408 fatcat:db6f66twxrfcjid4nyq5hs72mm

Energy-efficient computing for wildlife tracking

Philo Juang, Hidekazu Oki, Yong Wang, Margaret Martonosi, Li Shiuan Peh, Daniel Rubenstein
2002 ACM SIGOPS Operating Systems Review  
Over the past decade, mobile computing and wireless communication have become increasingly important drivers of many new computing applications. The field of wireless sensor networks particularly focuses on applications involving autonomous use of compute, sensing, and wireless communication devices for both scientific and commercial purposes. This paper examines the research decisions and design tradeoffs that arise when applying wireless peer-to-peer networking techniques in a mobile sensor
more » ... twork designed to support wildlife tracking for biology research. The ZebraNet system includes custom tracking collars (nodes) carried by animals under study across a large, wild area; the collars operate as a peer-to-peer network to deliver logged data back to researchers. The collars include global positioning system (GPS), Flash memory, wireless transceivers, and a small CPU; essentially each node is a small, wireless computing device. Since there is no cellular service or broadcast communication covering the region where animals are studied, ad hoc, peer-to-peer routing is needed. Although numerous ad hoc protocols exist, additional challenges arise because the researchers themselves are mobile and thus there is no fixed base station towards which to aim data. Overall, our goal is to use the least energy, storage, and other resources necessary to maintain a reliable system with a very high 'data homing' success rate. We plan to deploy a 30-node ZebraNet system at the Mpala Research Centre in central Kenya. More broadly, we believe that the domain-centric protocols and energy tradeoffs presented here for ZebraNet will have general applicability in other wireless azld sensor applications.
doi:10.1145/635508.605408 fatcat:tdklj5fd3vauzg5ppg4r52mvdq

Target-locking acquisition with real-time confocal (TARC) microscopy

Peter J. Lu, Peter A. Sims, Hidekazu Oki, James B. Macarthur, David A. Weitz
2007 Optics Express  
We present a real-time target-locking confocal microscope that follows an object moving along an arbitrary path, even as it simultaneously changes its shape, size and orientation. This Target-locking Acquisition with Realtime Confocal (TARC) microscopy system integrates fast image processing and rapid image acquisition using a Nipkow spinning-disk confocal microscope. The system acquires a 3D stack of images, performs a full structural analysis to locate a feature of interest, moves the sample
more » ... n response, and then collects the next 3D image stack. In this way, data collection is dynamically adjusted to keep a moving object centered in the field of view. We demonstrate the system's capabilities by target-locking freely-diffusing clusters of attractive colloidal particles, and activelytransported quantum dots (QDs) endocytosed into live cells free to move in three dimensions, for several hours. During this time, both the colloidal clusters and live cells move distances several times the length of the imaging volume.
doi:10.1364/oe.15.008702 pmid:19547205 fatcat:vql36jmddngq5oaw7uobqv3lf4

動的錯視現象と新しい型の視覚効果
Dynamic Illusion and New Types of Visual Effects

Masanori IDESAWA, Jun NAKAZA, Hidekazu Oki, Yutaka SAKAGUCHI
1995 ITE Technical Report  
キ ー ワ ー ド 3 次 元 錯 視 、動 的 錯 視 、 動 的視 覚 効 果 、 回 転 バ ー ニ ア 効 果 、 運 動 と 3 次 元 知 覚 、 隠 蔽 Dynamic [ ll 旺 siqn and Ne 騨 Types of Vis 旺 al Effects Masafiori IDESAWA, Jun NAKAZA, Eidekaz 旺 Oki, Yロtaka .  ... 
doi:10.11485/tvtr.19.33_15 fatcat:qgwtij3mmrdwjh2oucumrzk5nu

Mechanical properties of composite resin blocks for CAD/CAM

Sasipin LAUVAHUTANON, Hidekazu TAKAHASHI, Maho SHIOZAWA, Naohiko IWASAKI, Yuya ASAKAWA, Meiko OKI, Werner J. FINGER, Mansuang ARKSORNNUKIT
2014 Dental materials journal  
This study compared commercial composite resin blocks with one ceramic block for use in computer-aided design/computer aided manufacturing (CAD/CAM). Four composite resins, one composite ceramic, and one feldspar-ceramic block were investigated. Flexural strength (FS), flexural modulus (FM), and Vickers hardness (VH) were determined under three conditions: dry storage; immersion in water at 37°C for 7 days; and immersion in water at 37°C for 7 days followed by 10,000 thermocycles. After dry
more » ... age, FS ranged from 127 to 242 MPa, FM from 9.6 to 51.5 GPa, and VH from 64 to 455. Two-way ANOVA was performed for FS, FM and VH followed by Tukey's multiple comparison (α<0.05). Results demonstrated that the materials degraded after water immersion and thermocycling, but their properties were within the acceptable range for fabrication of single restorations according to the ISO standard for ceramics (ISO 6872:2008).
doi:10.4012/dmj.2014-208 pmid:25273052 fatcat:utla46yfwvbcjkzuztn2bhal3u

Discoloration of various CAD/CAM blocks after immersion in coffee

Sasipin Lauvahutanon, Maho Shiozawa, Hidekazu Takahashi, Naohiko Iwasaki, Meiko Oki, Werner J. Finger, Mansuang Arksornnukit
2017 Restorative Dentistry & Endodontics  
This study evaluated color differences (ΔEs) and translucency parameter changes (ΔTPs) of various computer-aided design/computer-aided manufacturing (CAD/CAM) blocks after immersion in coffee. Eight CAD/CAM blocks and four restorative composite resins were evaluated. The CIE L*a*b* values of 2.0 mm thick disk-shaped specimens were measured using the spectrophotometer on white and black backgrounds (n = 6). The ΔEs and ΔTPs of one day, one week, and one month immersion in coffee or water were
more » ... culated. The values of each material were analyzed by two-way ANOVA and Tukey's multiple comparisons (α = 0.05). The ΔEs after prophylaxis paste polishing of 1 month coffee immersion specimens, water sorption and solubility were also evaluated. After one month in coffee, ΔEs of CAD/CAM composite resin blocks and restorative composites ranged from 1.6 to 3.7 and from 2.1 to 7.9, respectively, and ΔTPs decreased. The ANOVA of ΔEs and ΔTPs revealed significant differences in two main factors, immersion periods and media, and their interaction except for ΔEs of TEL (Telio CAD, Ivoclar Vivadent). The ΔEs significantly decreased after prophylaxis polishing except GRA (Gradia Block, GC). There was no significant correlation between ΔEs and water sorption or solubility in water. The ΔEs of CAD/CAM blocks after immersion in coffee varied among products and were comparable to those of restorative composite resins. The discoloration of CAD/CAM composite resin blocks could be effectively removed with prophylaxis paste polishing, while that of some restorative composites could not be removed.
doi:10.5395/rde.2017.42.1.9 pmid:28194359 pmcid:PMC5299759 fatcat:bap4hk6ulbds3bnsks6qmyulwi

Effect of long-time immersion of soft denture liners in water on viscoelastic properties

Naohiko IWASAKI, Chisato YAMAKI, Hidekazu TAKAHASHI, Meiko OKI, Tetsuya SUZUKI
2017 Dental materials journal  
Aim of this study was to investigate the effect of long-time immersion of soft denture liners in 37°C water on viscoelastic properties. Six silicone-based and two acrylic resin-based soft denture liners were selected. Cylindrical specimens were stored in distilled water at 37°C for 6 months. Viscoelastic properties, which were instantaneous and delayed elastic displacements, viscous flow, and residual displacement, were determined using a creep meter, and analyzed with 2-way analysis of
more » ... and Tukey's comparison (α=0.05). Viscoelastic properties and their time-dependent changes were varied among materials examined. The observed viscoelastic properties of three from six silicone-based liners did not significantly change after 6-month immersion, but those of two acrylic resin-based liners significantly changed with the increase of immersion time. However, the sum of initial instantaneous elastic displacement and delayed elastic displacement of two acrylic resin-based liners during 6-month immersion changed less than 10%, which might indicate clinically sufficient elastic performance.
doi:10.4012/dmj.2016-320 pmid:28450673 fatcat:wkzfpqipzjax3e6jae7rejg2ri

In vitro evaluation of the wear resistance of composite resin blocks for CAD/CAM

Sasipin LAUVAHUTANON, Hidekazu TAKAHASHI, Meiko OKI, Mansuang ARKSORNNUKIT, Masafumi KANEHIRA, Werner J FINGER
2015 Dental materials journal  
The aim of the study was to investigate two-and three-body wear of CAD/CAM blocks. Four composite resins, one hybrid ceramic and one feldspar ceramic block material were examined. Six specimens each were tested in a ball-on-disc wear device fitted with a zirconia ball (50 N load, 1.2 Hz, 50 k cycles) in water for two-body and in poppy seed slurry for three-body wear evaluation. Volume loss after each 10 k cycle was quantified using a digital CCD microscope. Statistical analysis: ANOVA and
more » ... s multiple comparisons (α=0.05). Two-body wear for composite resin blocks was small, hybrid ceramic and ceramic blocks showed larger volume loss. Threebody wear was very low for all materials. All CAD/CAM block materials investigated displayed low wear compared to previous data for direct posterior composites carrying out the same wear test. The block materials are considered suitable for fabrication of single full crown restorations on premolar teeth.
doi:10.4012/dmj.2014-293 pmid:26235715 fatcat:v4itnrjdcrabjfxroceusgicby

Intraoperative Rapid Diagnosis via Contact Endoscopy
喉頭接触型内視鏡の迅速診断への応用

Miki KUSHIMA, Masafumi TAKMOTO, Hidetaka AKITA, Fumiyoshi OOYANAGI, Hidekazu OTA, Seido OKI, Harumi SUZAKI
2002 Practica Oto-Rhino-Laryngologica  
Surgeons and pathologists encounter some problems in making accurate intraoperative rapid diagnoses. The processing of histological and cytological specimens is time consuming, and further more, only small regions can be examined. In this study, we evaluated the use of a contact microlaryngoscope in microlaryngeal surgery, in 5 cases of suspicious squamous epithelial atypia, such as dysplasia and squamous cell carcinoma. After surgery, the rapid findings (suspected diagnosis) obtained using
more » ... act microlaryngoscopy were compared with the histological specimens (final diagnosis). The diagnoses matched in all 5 cases. Thus, contact microlaryngoscopy is useful for intraoperative rapid diagnosis.
doi:10.5631/jibirin.95.747 fatcat:266oci7vqngjjcchln4bc347vu

De novo ulcerative colitis after kidney transplantation treated with infliximab

Rikako Oki, Sumi Hidaka, Akiko Sasaki, Shinichi Teshima, Yasuhiro Mochida, Katsunori Miyake, Kunihiro Ishioka, Hidekazu Moriya, Takayasu Ohtake, Shuzo Kobayashi
2021 CEN Case Reports  
AbstractDiarrhea is a common complication in kidney transplant recipients. Common causes of diarrhea include infection, side effect from medication, rejection, and malignancy. A less common but important cause of diarrhea is de novo inflammatory bowel disease (IBD). This is unexpected, as these patients are already immunosuppressed. Herein, we present the case of a 45-year-old man with end-stage kidney disease because of focal segmental glomerulosclerosis who underwent preemptive kidney
more » ... ntation, with his mother as donor. His immunosuppressive regimen included methylprednisolone, mycophenolate mofetil, and tacrolimus. He had no episodes of graft dysfunction, rejection, or infectious events. Two and a half years post-transplantation, he developed bloody diarrhea. After excluding infections, colonoscopy was performed and revealed edematous mucosa and erythema with pigmentation, which are typical findings in ulcerative colitis. Despite therapy with 5-aminosalicylate and granulocyte monocyte apheresis, he presented with massive bloody diarrhea. We initiated infliximab, an anti-tumor necrosis factor-α (TNF-α) agent. He responded very well and achieved remission within 6 months after initiation of infliximab, while administration of the other immunosuppressants was maintained. His course was uneventful and no complications developed. Management of immunosuppressants for de novo IBD after organ transplantation is complicated, because treatment of IBD, graft function protection, and prevention of infection must be considered. Therefore, cooperation between transplantation physicians and gastroenterologists is essential during therapy.
doi:10.1007/s13730-021-00599-6 pmid:33829404 pmcid:PMC8494858 fatcat:kcmiz6vujjabnm5y7lsfmx4hde

Two cases of mammary secretory carcinoma of the breast
乳腺分泌癌の2例

Miki KUSHIMA, Hiroyoshi OKI, Norio KAWASE, Masafumi TAKIMOTO, Akira SHIOKAWA, Hidekazu OTA, Kazuo KAZAMA, Masako TUDA
1993 The Journal of the Japanese Society of Clinical Cytology  
doi:10.5795/jjscc.32.543 fatcat:lcfqrfuhdrdbhelp5pizkhhaly

Malignant Lymphoma Developing from Chronic Empyema Wall
EBウイルス陽性の膿胸後悪性リンパ腫の一剖検例

Toshiko Onizuka, Hiroyoshi Oki, Miki Kushima, Hidekazu Ota, Kazuo Kazama, Yasuyuki Morishita, Shigeo Mori
1994 Journal of the Japan Society of the Reticuloendothelial System  
A 74-year-old male, who had been treated with artificial pneumothorax for pulmonary tuberculosis 38 years before, was admitted with fever on May 1992. Chest X-ray revealed the presence of scarred empyema in the right thorax, whereas the abdominal computed tomography indicated the presence of tumor extending from the pleural wall to the liver. The aspirated pleural effusion was suggestive of malignant lymphoma. He died in september 1992. Autopsy revealed non-Hodgkin's malignant lymphoma of
doi:10.3960/jslrt1961.34.185 fatcat:iyxusck7qvalxohsig4t3xn4am

Intravascular lymphoma forming massive aortic tumors complicated with sarcoidosis and focal segmental glomerulosclerosis: a case report and literature review

Yasuhiro Oda, Kunihiro Ishioka, Takayasu Ohtake, Shuku Sato, Yotaro Tamai, Rikako Oki, Kenji Matsui, Yasuhiro Mochida, Hidekazu Moriya, Sumi Hidaka, Shuzo Kobayashi
2018 BMC Nephrology  
Intravascular large B-cell lymphoma (IVLBCL) is a rare subtype of extranodal diffuse large B-cell lymphoma characterized by proliferation of B cells within small vessels. Herein, we report a case of a 77-yearold man who presented with IVLBCL and massive tumor formation on the aortic wall who was previously diagnosed with sarcoidosis and focal segmental glomerulosclerosis (FSGS). To our knowledge, this is the first reported case of an IVLBCL with aortic tumor formation. Case presentation: A
more » ... ar-old ambulatory man with sarcoidosis and FSGS had neurological symptoms for nine months. The patient presented to the emergency department with sudden left leg pain, and was diagnosed with acute femoral artery occlusion. Emergency thrombectomy was performed subsequently. Pathological evaluation of the thrombi revealed that its surface was filled with large atypical B cells. Bone marrow biopsy showed infiltration of large atypical B cells within the small vessels. IVLBCL was suspected and further examination was planned, but the patient died due to sudden respiratory and cardiac arrest on hospital day twelve. Autopsy revealed intravascular tumors adherent to the aortic arch, left ventricle, and the abdominal aorta. All enlarged lymph nodes and the ventricular septum of the heart showed hyalinized lesions with granular formation consistent with sarcoidosis. The patient was diagnosed with IVLBCL with aortic tumor formation complicated with sarcoidosis and FSGS. Conclusions: IVLBCL may present with tumor formation on the aortic wall. Although the cause of its affinity to the aortic wall is yet unknown, autopsy findings imply that arteriosclerosis may have contributed to the tumor formation. The literature suggests that T-cell abnormalities could possibly be the common etiology of intravascular lymphoma, sarcoidosis, and FSGS.
doi:10.1186/s12882-018-1106-z fatcat:2sthvzjsjfbd3a6nilwofkqttq
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