Publish in OALib Journal

ISSN: 2333-9721

APC: Only $99


Any time

2019 ( 3 )

2017 ( 4 )

2016 ( 2 )

2015 ( 10 )

Custom range...

Search Results: 1 - 10 of 190 matches for " Motohisa Kuwahara "
All listed articles are free for downloading (OA Articles)
Page 1 /190
Display every page Item
A Surgical Case of Bilateral Pulmonary Metastases from Thyroid Follicular Cancer  [PDF]
Motohisa Kuwahara, Masato Iwami, Masae Mano, Toshihiko Moroga, Akinori Iwasaki
Surgical Science (SS) , 2015, DOI: 10.4236/ss.2015.610063
Abstract: An 80-year-old woman underwent a bilateral lung resection for metastases originating from follicular thyroid cancer. The resection was performed 30 years after right hemithyroidectomy to remove the follicular adenoma. Chest X-ray revealed a 30-mm mass shadow in the right lower lung filed. Chest computed tomography revealed a 32-mm mass shadow in right lung segment 10 (S10) and a 15-mm nodular shadow in left S10. Another partial lung resection of left S10 and a right lower lobectomy were performed 3 months later. Although rarely performed, resection of bilateral pulmonary metastases arising from follicular thyroid cancer was conducted for this patient.
Pulmonary metastasis from gastric cancer: A case report and review of literature  [PDF]
Motohisa Kuwahara, Mari Matsumoto, Kazuya Naritomi, Masae Mano, Daisuke Hamatake, Koji Inutsuka, Takayuki Shirakusa, Akinori Iwasaki
Advances in Lung Cancer (ALC) , 2013, DOI: 10.4236/alc.2013.23009

We present a case report of a 63-year-old male who underwent lung resections for metastases originating from gastric cancer 18-year after total gastrectomy with lymphadenectomy. The gastrectomy was performed in 1994; histological examination of the original tumor revealed stage II poorly differentiated adenocarcinoma [pT2 (MP), N0, M0]. Chest X-ray and computed tomography in 2012 showed a well-defined tumor, 9 mm in size, at the left S3 of the lung. Thoracoscopic partial resection was performed. The tumor was diagnosed as poorly differentiated carcinoma, most likely metastatic gastric adenocarcinoma. Although rarely performed, resection of pulmonary metastases from carcinoma of the stomach was done to improve the patient’s chances for long-term survival.

Chest Wall Hemangiopericytoma-Like Solitary Fibrous Tumor of the Pleura: Case Report with Computed Tomography Findings*  [PDF]
Motohisa Kuwahara, Hiroshi Nishimura, Masato Iwami, Kazuya Naritomi, Masae Mano, Koji Inutsuka, Keita Tokuishi, Akinori Iwasaki
Advances in Computed Tomography (ACT) , 2013, DOI: 10.4236/act.2013.24022

We present a case report of a 65-year-old woman who underwent resection of a chest wall tumor. In contrast with computed tomography, the tumor exhibited hypervascularity and was fed from the 9th intercostals artery. Histologically, the tumor was diagnosed as a cellular variant of solitary fibrous tumor of the pleura, with branching “staghorn” vessels and hypervascularity. The tumor thus resembled a chest wall hemangiopericytoma.

Three Inverted Meckel’s Diverticula Cases with Ileus Diagnosed Preoperatively and Treated Laparoscopically  [PDF]
Kazuya Naritomi, Yuya Tanaka, Hiroki Ureshino, Yoshihiro Uchino, Motohisa Kuwahara, Yuhei Kitazato, Masahiro Kawabata, Masae Mano
Surgical Science (SS) , 2016, DOI: 10.4236/ss.2016.72009
Abstract: We have experienced three inverted Meckel’s diverticula with ileus that are diagnosed before surgery and treated with laparoscopic surgery. The patients were 22, 26, and 29 years of age. The history of ileus for each patient differed, being the first experience for one patient, the second for another, and the third experience for the remaining patient. None of these patients had a history of abdominal surgery. Conservative therapy eventually improved the existing symptoms, but the cause of past ileus remained unclear. Elective surgery was performed 12 days from the onset of symptoms on two of the patients after improving the ileus by inserting a long tube into the bowel. Emergency surgery was performed on the same day of admission on the remaining case that involved moderate expansion of intestine. In these patients, the first trocar was inserted into the umbilicus region. Laparoscopic surgery was then performed with three trocars. The patients were discharged upon favorable outcome after surgery. No recurrence of ileus was noted post-surgery. Laparoscopy was useful both to diagnose and treat ileus of a Meckel’s diverticulum.
Probability Theory Predicts That Chunking into Groups of Three or Four Items Increases the Short-Term Memory Capacity  [PDF]
Motohisa Osaka
Applied Mathematics (AM) , 2014, DOI: 10.4236/am.2014.510140

Short-term memory allows individuals to recall stimuli, such as numbers or words, for several seconds to several minutes without rehearsal. Although the capacity of short-term memory is considered to be 7 ± 2 items, this can be increased through a process called chunking. For example, in Japan, 11-digit cellular phone numbers and 10-digit toll free numbers are chunked into three groups of three or four digits: 090-XXXX-XXXX and 0120-XXX-XXX, respectively. We use probability theory to predict that the most effective chunking involves groups of three or four items, such as in phone numbers. However, a 16-digit credit card number exceeds the capacity of short-term memory, even when chunked into groups of four digits, such as XXXX-XXXX-XXXX-XXXX. Based on these data, 16-digit credit card numbers should be sufficient for security purposes.

Modified Kuramoto Phase Model for Simulating Cardiac Pacemaker Cell Synchronization  [PDF]
Motohisa Osaka
Applied Mathematics (AM) , 2017, DOI: 10.4236/am.2017.89092
Abstract: It has been suggested that sick sinus syndrome, which is due to the dysfunction of the sinus node, may result from the sparser gap junctions and/or lower intrinsic frequencies of pacemaker cells that occur with aging. Hence, in this paper, the synchronization mechanism of pacemaker cells that lie in the sinus node of the heart is examined using a modified Kuramoto phase model. Although each element always interacts with all the others in the Kuramoto phase model, in the proposed model, each element interacts only with the neighbors over a certain time (called the interaction time) during Phase 4 of the action potential. The pacemaker cell elements are arranged on a square lattice, and each element connects with the elements surrounding it. The results indicate that the diversity of intrinsic frequencies of pacemaker cells may be necessary for synchronization. Moreover, increasing the proportion of invalid connections causes the elements to take more time to synchronize until eventually they do not synchronize at all, and decreasing the intrinsic frequencies of the elements prevents them from synchronizing. Probably these elucidate the cause of sick sinus syndrome.
Probability Theory Predicts That Group Survival May Be Guaranteed for Groups with More Than 10 Elements  [PDF]
Motohisa Osaka
Applied Mathematics (AM) , 2017, DOI: 10.4236/am.2017.812125
The purpose of this study is to find out the critical number of elements needed for group survival. Taking a probabilistic approach, how the lifetime of a group consisting of several elements depends on the number of elements and the probability distribution of their lifetimes is investigated. Four probability distributions are examined: an exponential distribution, a uniform distribution, a parabolic distribution, and a pointed distribution composed of two parabolas. The lifetime of the group is defined as the expected value of the maximum lifetime of the elements in that group. The probability distribution of this maximum shifts to the right as the number of elements increases, and the expected value of the lifetime of each element eventually becomes less than the lower limit of this distribution. The number of elements in this case is defined as the critical number of elements needed for group survival. Hence, if the number of elements is larger than the critical number needed for group survival, the lifetime of the group is guaranteed to be longer than the expected lifetime of one element. The findings are in the following. The critical number needed for group survival is inversely proportional to the expected lifetime of one element, regardless of the probability distribution used. It decreases as \"\"for an exponential distribution, and as \"\"in case of the others, where N is the number of elements of the group. Because a probability distribution defined over a finite range is assumed to be reasonable in practice, a group consisting of more than 10 elements should survive well.
A Probabilistic Method to Determine Whether the Speed of Light Is Constant  [PDF]
Motohisa Osaka
Applied Mathematics (AM) , 2019, DOI: 10.4236/am.2019.102005
Abstract: Although the formula of mass-energy equivalence was derived from the hypothesis that the speed of light in free space is constant, conversely, the purpose of this research is to show that a method of probabilistically determining whether the speed of light is constant is derived from this formula. By considering the formula of mass-energy equivalence to be a function of the energy of an object moving at speed V, the probability density function (PDF) of the energy can be obtained using the inverse function of this formula, if the speed of light obeys a probability distribution. The main result is that the PDF of the energy diverges to infinity at a certain energy value regardless of the PDF of the speed of light. Thus, when the speed calculated from this value enters a certain range of the speed of light as V increases stepwise from below 299,792,458 m/s, the PDF of the energy should increase abruptly. If not, then the speed of light is constant. This is the method of probabilistically determining whether the speed of light is constant. An experimental method is proposed to confirm this.
Simplification of additivity conjecture in quantum information theory
Motohisa Fukuda
Physics , 2006, DOI: 10.1007/s11128-007-0051-8
Abstract: We simplify some conjectures in quantum information theory; the additivity of minimal output entropy, the multiplicativity of maximal output p-norm and the superadditivity of convex closure of output entropy. We construct a unital channel for a given channel so that they share the above additivity properties; we can reduce the conjectures for all channels to those for unital channels.
An application of decomposable maps in proving multiplicativity of low dimensional maps
Motohisa Fukuda
Mathematics , 2009, DOI: 10.1063/1.3277186
Abstract: In this paper we present a class of maps for which the multiplicativity of the maximal output p-norm holds when p is 2 and p is larger than or equal to 4. The class includes all positive trace-preserving maps from the matrix algebra on the three-dimensional space to that on the two-dimensional.
Page 1 /190
Display every page Item

Copyright © 2008-2017 Open Access Library. All rights reserved.