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Surface and Internal Waves due to a Moving Load on a Very Large Floating Structure
Taro Kakinuma,Kei Yamashita,Keisuke Nakayama
Journal of Applied Mathematics , 2012, DOI: 10.1155/2012/830530
Abstract: Interaction of surface/internal water waves with a floating platform is discussed with nonlinearity of fluid motion and flexibility of oscillating structure. The set of governing equations based on a variational principle is applied to a one- or two-layer fluid interacting with a horizontally very large and elastic thin plate floating on the water surface. Calculation results of surface displacements are compared with the existing experimental data, where a tsunami, in terms of a solitary wave, propagates across one-layer water with a floating thin plate. We also simulate surface and internal waves due to a point load, such as an airplane, moving on a very large floating structure in shallow water. The wave height of the surface or internal mode is amplified when the velocity of moving point load is equal to the surface- or internal-mode celerity, respectively.
Three-Year Outcome of Very Low Birth Weight Infants in Conservatively Managed Premature Rupture of Membranes  [PDF]
Jun Sasahara, Keisuke Ishii, Toshiko Kishimoto, Akiko Yamashita, Shusaku Hayashi, Nobuaki Mitsuda
Open Journal of Obstetrics and Gynecology (OJOG) , 2015, DOI: 10.4236/ojog.2015.51010
Abstract:

Aim: To elucidate the outcome for very low birth weight infants delivered after preterm premature rupture of membranes (PPROM) managed conservatively, and to determine the prognostic value of perinatal factors for long-term outcome. Methods: Perinatal data were collected from medical records for singleton live-birth infants delivered between 1991 and 2008 after conservatively managed PPROM. Cases of congenital anomalies and chromosomal aberrations were excluded. Poor outcome was defined as a composite measure of death, neurological morbidity including cerebral palsy, or neurodevelopmental delay. Associations between perinatal factors and poor outcome at the corrected age of 3 were estimated using logistic regression analysis. Results: After the exclusion, 356 infants meeting the study criteria were identified, 26 cases were lost to follow-up, and 330 were eligible at 3 years. The mortality rate was 10% and the incidence of neurological morbidities was 12%. Logistic regression analysis revealed gestational age at birth [adjusted odds ratio (aOR) 0.815], and five-minute Apgar scores (aOR 0.521) were independent predictors for poor outcome. Conclusion: When PPROM was managed conservatively, 22% of VLBW infants had a poor outcome at corrected age of 3 years. Early gestational age at birth and low Apgar scores were associated with poor outcome.

Superior Retinacular Artery Did Not Occlude in a Rat Model of the Non-Traumatic Osteonecrosis of the Femoral Head  [PDF]
Shunichiro Okazaki, Satoshi Nagoya, Junya Shimizu, Nobuyuki Takahashi, Keisuke Mizuo, Hideki Hyodoh, Kenji Tateda, Ima Kosukegawa, Satoshi Watanabe, Toshihiko Yamashita
Open Journal of Orthopedics (OJO) , 2016, DOI: 10.4236/ojo.2016.66022
Abstract: Non-traumatic osteonecrosis of the femoral head (ONFH) is believed to be avascular necrosis. Certainly, a disruption of a supplying artery induces necrosis in the supplying artery-dominant region. However, when an abnormality such as cell apoptosis, or another reason, is developed in the supplying artery-dominant region, it induces a disruption of the supplying artery. Therefore, to prove that ONFH is avascular necrosis, it is necessary to demonstrate the disruption of the supplying artery prior to histological osteonecrosis development. Here we investigate histologically, using a rat model, whether disruption of the supplying artery occurs before the initial development of ONFH following corticosteroid treatment. Rats were given imiquimod and methylprednisolone, and were sacrificed 1, 2, 3, 7 or 14 days after the last injection. At the sacrifice, the rat was perfused with 20 ml black Indian ink through the left ventricle. ONFH was observed in the Imiquimod + Methylprednisolone group at 7 and 14 days. The osteonecrotic area was not stained with perfused black Indian ink. However, the lateral portion of the femoral head near the superior retinacular artery was stained with the ink. In conclusion, the present study shows that the superior retinacular artery did not occlude before the initial development of ONFH histologically in rats.
Hydrogen Evolution from Water under Visible-Light Irradiation Using Keggin-Type Platinum(II)-Coordinated Phospho-, Silico-, and Germanotungstates as Co-Catalysts  [PDF]
Chika Nozaki Kato, Shunsaku Suzuki, Yuki Ihara, Koki Aono, Rie Yamashita, Keisuke Kikuchi, Tetsuji Okamoto, Hidemitsu Uno
Modern Research in Catalysis (MRC) , 2016, DOI: 10.4236/mrc.2016.54010
Abstract: The tetramethylammonium salts of diplatinum(II) complexes composed of mono-lacunary Keggin-type silico and germanotungstates, [(CH3)4N]4[α-SiW11O39{cis-Pt(NH3)2}2]·13H2O (TMA-Si-Pt) and [(CH3)4N]4[α-GeW11O39{cis-Pt(NH3)2}2]·11H2O (TMA-Ge-Pt), were synthesized and crystallized. Single crystals of a tetramethylammonium salt of Keggin-type diplatinum(II)-coordinated phosphotungstate [(CH3)4N]3[α-PW11O39{cis-Pt(NH3)2}2]×10H2O (TMA-P-Pt) were also obtained. The X-ray structural analyses revealed that the two cis-platinum(II) moieties, [cis-Pt(NH3)2]2+, were each coordinated to two oxygen atoms in a mono-vacant site of [XW11O39](12-n)- (Xn+ = Si4+, Ge4+, P5+). FTIR spectra of TMA-Si-Pt and TMA-Ge-Pt also suggested that the two platinum(II) moieties were coordinated to the vacant site of [SiW11O39]8- and [GeW11O39]8-. The 1H NMR spectra in DMSO-d6 of TMA-Si-Pt and TMA-Ge-Pt showed signals assigned to the two sets of NH3 ligands coordinated to the platinum sites. These three platinum compounds showed hydrogen evolution from aqueous triethanolamine solution under visible light irradiation (λ ≥ 400 nm) in the presence of eosin Y, α-Keggin mono-aluminum-substituted silicotungstate, and titanium dioxide. The catalytic activities were influenced by the central atoms, and TMA-P-Pt showed the highest activities among the three platinum compounds.
西南日本秋吉带石炭系高山(Ko-yama)灰岩群的褶皱构造
Noriyuki INADA,Shigeyuki SUZUKI,Keisuke ISHIDA,Shinji YAMASHITA
地球学报 , 2012, DOI: 10.3975/cagsb.2012.s1.13
Abstract: ThestudyareaislocatedinKawakami-cho,OkayamaPrefecture,whichisoccupiedbyLowerCarboniferoustoMiddlePermianKo-yamaLimestoneGroup(Yokoyamaetal.,1979),PermianYoshiiGroup(Sanoetal.,1987)andTriassicNariwaGroup(Tera-oka,1959).TheNariwaGroupunconformablycoversthePaleozoicsuccessions(Otoh,1985).Thesesucces-sionsbelongtotheAkiyoshiBelt.TheKo-yamaLimestoneGroupiscomposedmainlyofmassivelimestone,withbasicvolcanicrocks,acidictuffandchert.Thegroupwasdatedbyforaminiferandfusu-linidasLowerCarboniferoustoMiddlePermian(Yo-koyamaetal.,1979).
西南日本秋吉带石炭系高山(Ko-yama)灰岩群的石炭纪(Visean–Moscovian)牙形石序列
Keisuke ISHIDA,Sigeyuki SUZUKI,Noriyuki INADA,Shinji YAMASHITA
地球学报 , 2012, DOI: 10.3975/cagsb.2012.s1.14
Abstract: TheCarboniferousconodontfaunalsuccessionofthelowerpartofKo-yamaLimestoneGroupwasstudied.TheconfirmedupperVisean–lowerMoscovianlithostratigraphyofthegroupischaracterizedbytheclasticcarbonateswithcommonassociationofthebasalticpyroclasticsandsomeintercalationofspicularchertbeds.ThefaunalsuccessionofGnathodussemiglaber(upperVisean),Gnathoduspraebilineatus–Lochrieamultinodosa(upperVisean),Lochrieaziegleri–Gnathodusgirtyigirtyis.l.(lowerSerpukhovian),Neoganthodussymmetricus–Idiognathodusprimulus(middle–upperBashkirian),andIdiognathoidesconvexus–Gondolellaclarki(lowerMoscovian)faunas,appearsinconcordancewiththelithostratigraphicorder.ThefaunasarecorrelativewiththosefromtheconodontzonesoftheHina,Atetsu,AkiyoshiandOmilimestonegroupsintheAkiyoshiBelt.TheVisean/SerpukhovianboundaryofthesectionwasrecognizedbytheFADofLochrieaziegleri.
Ameliorative effects of polyunsaturated fatty acids against palmitic acid-induced insulin resistance in L6 skeletal muscle cells
Keisuke Sawada, Kyuichi Kawabata, Takatoshi Yamashita, Kengo Kawasaki, Norio Yamamoto, Hitoshi Ashida
Lipids in Health and Disease , 2012, DOI: 10.1186/1476-511x-11-36
Abstract: In this study, we established a high-throughput assay to screen for compounds that can improve myocellular insulin resistance, which was based on a previously reported non-radioisotope 2-deoxyglucose (2DG) uptake assay. Insulin-resistant muscle cells were prepared by treating rat L6 skeletal muscle cells with 750 μM palmitic acid for 14 h. Using the established assay, the impacts of several fatty acids on myocellular insulin resistance were determined.In normal L6 cells, treatment with saturated palmitic or stearic acid alone decreased 2DG uptake, whereas unsaturated fatty acids did not. Moreover, co-treatment with oleic acid canceled the palmitic acid-induced decrease in 2DG uptake activity. Using the developed assay with palmitic acid-induced insulin-resistant L6 cells, we determined the effects of other unsaturated fatty acids. We found that arachidonic, eicosapentaenoic and docosahexaenoic acids improved palmitic acid-decreased 2DG uptake at lower concentrations than the other unsaturated fatty acids, including oleic acid, as 10 μM arachidonic acid showed similar effects to 750 μM oleic acid.We have found that polyunsaturated fatty acids, in particular arachidonic and eicosapentaenoic acids prevent palmitic acid-induced myocellular insulin resistance.Insulin resistance is an impaired response to insulin in specific organs or cells such as liver, fat and muscle, and is strongly associated with the development of obesity and type 2 diabetes [1]. Elevated plasma free fatty acid levels is an important factor, because it causes insulin resistance in skeletal muscle, the major site for blood glucose disposal [2]. Thus, many studies have been reported on the relationship between fatty acids and insulin resistance, and revealed that saturated fatty acids, particularly palmitic acid, induce insulin resistance in myotubes [3], whereas unsaturated fatty acids do not [4,5]. In skeletal muscle, insulin resistance is mediated by the intramyocellular accumulation of the metabo
Ex-vivo porcine organs with a circulation pump are effective for teaching hemostatic skills
Yoshimitsu Izawa, Shuji Hishikawa, Tomohiro Muronoi, Keisuke Yamashita, Masayuki Suzukawa, Alan T Lefor
World Journal of Emergency Surgery , 2012, DOI: 10.1186/1749-7922-7-5
Abstract: Simulation training for surgical skills has become essential around the world. Many methods including dry laboratories, simulators, cadavers, and live tissues have been used for basic surgical skill training, open surgery training, and laparoscopic training [1]. To improve trauma surgery education, many educational training courses have been developed. Specifically, many simulation courses such as Advanced Trauma Operative Management, Definitive Surgical Trauma Care, and Advanced Surgical Skills for Exposure in Trauma have been held around the world [2-7].Among the various possible approaches, live animal training may be most suitable for teaching hemostatic skills [1]. However, these courses are expensive and it is difficult to provide repetitive training because they utilize live animal models necessitating general anesthesia, as well as much time and effort. Recently, the use of live animals is decreasing in surgical training. The validity of using a simulated model instead of live animals has been validated for chest tube placement and cricothyrotomy [8]. In addition, it is critically important to adopt the 3R approach to the use of animal models, including Reduction, Refinement and Replacement, originally described in 1959 [9].Simulation training programs may not be suitable for certain kinds of training because the bleeding encountered is not similar to live animals. Ex-vivo training as a type of simulation for surgical education is a less realistic model of hemorrhage than a live animal. However, such courses may be relatively inexpensive and allow repetitive training [1].Recently, with fewer opportunities to participate in live animal training due to economic and ethical aspects, and limited trauma operative experience during training, residents may not be able to learn adequate hemostatic skills in clinical trauma situations alone [10]. In order to improve the competency of residents in basic hemostatic skills in the trauma setting, we created this realisti
Wind Tunnel Testing on Start/Unstart Characteristics of Finite Supersonic Biplane Wing
Hiroshi Yamashita,Naoshi Kuratani,Masahito Yonezawa,Toshihiro Ogawa,Hiroki Nagai,Keisuke Asai,Shigeru Obayashi
International Journal of Aerospace Engineering , 2013, DOI: 10.1155/2013/231434
Abstract: This study describes the start/unstart characteristics of a finite and rectangular supersonic biplane wing. Two wing models were tested in wind tunnels with aspect ratios of 0.75 (model A) and 2.5 (model B). The models were composed of a Busemann biplane section. The tests were carried out using supersonic and transonic wind tunnels over a Mach number range of with angles of attack of 0°, 2°, and 4°. The Schlieren system was used to observe the flow characteristics around the models. The experimental results showed that these models had start/unstart characteristics that differed from those of the Busemann biplane (two dimensional) owing to three-dimensional effects. Models A and B started at lower Mach numbers than the Busemann biplane. The characteristics also varied with aspect ratio: model A ( ) started at a lower Mach number than model B ( ) owing to the lower aspect ratio. Model B was located in the double solution domain for the start/unstart characteristics at , and model B was in either the start or unstart state at . Once the state was determined, either state was stable. 1. Introduction A sonic boom is caused by shock waves and expansion waves generated by a supersonic aircraft. As the sonic boom generates an impulsive noise at the ground, it produces undesirable effects on not only people but also animals and architecture. Sonic boom mitigation is thus required for the development of supersonic commercial aircraft [1, 2], and extensive studies have been carried out regarding this [3, 4]. Recently, Kusunose et al. proposed the supersonic biplane theory [5–8] as a method of sonic boom mitigation. This theory enables significant reduction if not complete elimination of shock waves and expansion waves by the wave reduction and wave cancellation effects of a biplane configuration. The concept of a Busemann biplane, which was first proposed by Busemann in 1935 [9, 10], forms the basis of supersonic biplane theory. Figure 1 shows the Busemann biplane (two dimensional) in a supersonic flow; this biplane consists of two half-diamond airfoils facing each other. Figure 1(a) shows the start state: compression (shock) waves generated from the leading edge of the elements are canceled by an expansion wave at the shoulder; the wave drag due to thickness is reduced significantly by the mutual cancellation of waves. Thus, the waves propagating outside the elements can be eliminated. Figure 1(b) shows the unstart state: a curved bow shock forms in front of the elements owing to the choked-flow phenomenon; the wave drag increases greatly. Naturally, a strong
Ex-vivo and live animal models are equally effective training for the management of a penetrating cardiac injury
Alan Kawarai Lefor,Hiroyuki Maruyama,Keisuke Yamashita,Masayuki Suzukawa,Shuji Hishikawa,Tomohiro Muronoi,Yoshimitsu Izawa
- , 2016, DOI: 10.1186/s13017-016-0104-3
Abstract: Live tissue models are considered the most useful simulation for training in the management for hemostasis of penetrating injuries. However, these models are expensive, with limited opportunities for repetitive training. Ex-vivo models using tissue and a fluid pump are less expensive, allow repetitive training and respect ethical principles in animal research. The purpose of this study is to objectively evaluate the effectiveness of ex-vivo training with a pump, compared to live animal model training. Staff surgeons and residents were divided into live tissue training and ex-vivo training groups. Training in the management of a penetrating cardiac injury was conducted for each group, separately. One week later, all participants were formally evaluated in the management of a penetrating cardiac injury in a live animal
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