8,385 research outputs found

    ESTIMATION OF KNEE EXTENSION MOMENT CONSIDERING VELOCITY EFFECT AND MUSCLE ACTIVATION USING TENDON SLACK LENGTH OPTIMIZATION

    Get PDF
    This study presents a model to estimate knee extension moment considering muscle velocity effect and muscle activation. The muscle tendon force is very sensitive to the tendon slack length. To predict tendon slack length, exact muscle parameters of a human are needed. But it is difficult to measure all of the muscle parameters from human body. So we propose the algorithm which finds the tendon slack length of quadriceps for more accurate estimation of knee extension moment. Finally considering muscle velocity effect and muscle activation, knee extension moment is estimated. Algorithm was embodied by MATLAB optimization toolbox. And it is evaluated by using an experimental data

    Calabi-Yau manifolds from pairs of non-compact Calabi-Yau manifolds

    Full text link
    Most of Calabi-Yau manifolds that have been considered by physicists are complete intersection Calabi-Yau manifolds of toric varieties or some quotients of product types. Purpose of this paper is to introduce a different and rather new kind of construction method of Calabi-Yau manifolds by pasting two non-compact Calabi-Yau manifolds. We will also in some details explain a curious and mysterious similarity with construction of some G2G_2-manifolds (also called Joyce manifolds), which are base spaces for M-theory.Comment: 10 pages. Accepted for publication in JHE

    Anatomy of the superior hypogastric plexus and its application in nerve-sparing paraaortic lymphadenectomy

    Get PDF
    Background: The purpose of this study was to clarify the anatomy of the superior hypogastric plexus, which would contribute to advancement of nerve-sparing paraaortic lymphadenectomy. Materials and methods: Eighteen cadavers were dissected and morphometrically analysed based on photographic images. Anatomical landmarks such as aortic bifurcation, transitional points of abdominal aorta to bilateral common iliac arteries, and cross point of the right ureter and pelvic brim, and cross point of sigmoid mesentery and pelvic brim were selected as reference points. Results: The left lowest lumbar splanchnic nerve was located more laterally to transitional point of abdominal aorta to in 11/18 specimens, whereas the right lowest lumbar splanchnic nerve passed onto the right transitional point in only one specimen. The lowest lumbar splanchnic nerves or the superior hypogastric plexus covered the aortic bifurcation in 11/18 specimens. The superior hypogastric plexus was separate from the cross point of right ureter and pelvic brim as well as cross point of sigmoid mesentery and pelvic brim. Conclusions: The superior hypogastric plexus is at risk of injury during paraaortic lymphadenectomy because of its topography. Preservation of the superior hypogastric plexus regarding its anatomic basis during paraaortic lymphadenectomy is required

    Syntactic comprehension of relative clauses and center embedding using pseudowords

    Get PDF
    Relative clause (RC) formation and center embedding (CE) are two primary syntactic operations fundamental for creating and understanding complex sentences. Ample evidence from previous cross-linguistic studies has revealed several similarities and differences between RC and CE. However, it is not easy to investigate the effect of pure syntactic constraints for RC and CE without the interference of semantic and pragmatic interactions. Here, we show how readers process CE and RC using a self-paced reading task in Korean. More interestingly, we adopted a novel self-paced pseudoword reading task to exploit syntactic operations of the RC and CE, eliminating the semantic and pragmatic interference in sentence comprehension. Our results showed that the main effects of RC and CE conform to previous studies. Furthermore, we found a facilitation effect of sentence comprehension when we combined an RC and CE in a complex sentence. Our study provides a valuable insight into how the purely syntactic processing of RC and CE assists comprehension of complex sentences

    Toda systems in closed string tachyon condensation

    Full text link
    We consider tt∗tt^* equations appearing in the study of localized tachyon condensations. They are described by various Toda system when we consider the condensation by the lowest tachyon corresponding to the monomial xyxy. The tachyon potential is calculated as a solution to these equations. The Toda system appearing in the deformation of \C^2/\Z_n by xyxy is identical to that of DnD_n singularity deformed by xx. For \C^3/\Z_n with xyzxyz deformation, we find only generic non-simple form, similar to the case appearing in \C/\Z_5\to \C/\Z_3 and we discuss the difficulties in these cases.Comment: 20 pages, no figur

    Trends in Tissue Engineering for Blood Vessels

    Get PDF
    Over the years, cardiovascular diseases continue to increase and affect not only human health but also the economic stability worldwide. The advancement in tissue engineering is contributing a lot in dealing with this immediate need of alleviating human health. Blood vessel diseases are considered as major cardiovascular health problems. Although blood vessel transplantation is the most convenient treatment, it has been delimited due to scarcity of donors and the patient's conditions. However, tissue-engineered blood vessels are promising alternatives as mode of treatment for blood vessel defects. The purpose of this paper is to show the importance of the advancement on biofabrication technology for treatment of soft tissue defects particularly for vascular tissues. This will also provide an overview and update on the current status of tissue reconstruction especially from autologous stem cells, scaffolds, and scaffold-free cellular transplantable constructs. The discussion of this paper will be focused on the historical view of cardiovascular tissue engineering and stem cell biology. The representative studies featured in this paper are limited within the last decade in order to trace the trend and evolution of techniques for blood vessel tissue engineering

    Time-Resolved Optical Pump-Resonant X-ray Probe Spectroscopy of 4-Thiouracil: A Simulation Study

    Get PDF
    We theoretically monitor the photoinduced ∗ → n∗ internal conversion process in 4-thiouracil (4TU), triggered by an optical pump. The element-sensitive spectroscopic signatures are recorded by a resonant X-ray probe tuned to the sulfur, oxygen, or nitrogen K-edge. We employ high-level electronic structure methods optimized for core-excited electronic structure calculation combined with quantum nuclear wavepacket dynamics computed on two relevant nuclear modes, fully accounting for their quantum nature of nuclear motions. We critically discuss the capabilities and limitations of the resonant technique. For sulfur and nitrogen, we document a pre-edge spectral window free from ground-state background and rich with ∗ and n∗ absorption features. The lowest sulfur K-edge shows strong absorption for both ∗ and n*. In the lowest nitrogen K-edge window, we resolve a state-specific fingerprint of the ∗ and an approximate timing of the conical intersection via its depletion. A spectral signature of the n∗ transition, not accessible by UV-vis spectroscopy, is identified. The oxygen K-edge is not sensitive to molecular deformations and gives steady transient absorption features without spectral dynamics. The */n∗ coherence information is masked by more intense contributions from populations. Altogether, element-specific time-resolved resonant X-ray spectroscopy provides a detailed picture of the electronic excited-state dynamics and therefore a sensitive window into the photophysics of thiobases

    Ischemic Necrosis Caused by Retroanastomotic Hernia after Subtotal Gastrectomy

    Get PDF
    After gastrojejunostomy, a small space can occur between the jejunum at the anastomosis site, the transverse mesocolon, and retroperitoneum, which may cause an intestinal hernia. This report presents a rare case of intestinal ischemic necrosis caused by retroanastomotic hernia after subtotal gastrectomy. A 56-year-old male was admitted to Kangwon National University Hospital with melena, abdominal pain, and nausea. His only relevant medical history was gastrectomy due to stomach cancer. Endoscopic findings revealed subtotal gastrectomy with Billroth-II reconstruction and a bluish edematous mucosal change with necrotic tissue in afferent and efferent loops including the anastomosis site. Abdominopelvic CT showed strangulation of proximal small bowel loops due to mesenteric torsion and thickening of the wall of the gastric remnant. Emergency laparotomy was performed. Surgical findings revealed the internal hernia through the defect behind the anastomosis site with strangulation of the jejunum between 20 cm below the Treitz ligament and the proximal ileum. Roux-en-Y anastomosis was performed, and he was discharged without complication. Retroanastomotic hernia, also called Petersen\u27s space hernia, is a rare complication after gastric surgery, cannot be easily recognized, and leads to strangulation
    • …
    corecore