Advanced search    

Search: authors:"Hajime Otsuka"

21 papers found.
Use AND, OR, NOT, +word, -word, "long phrase", (parentheses) to fine-tune your search.

SO(32) heterotic line bundle models

AbstractWe search for the three-generation standard-like and/or Pati-Salam models from the SO(32) heterotic string theory on smooth, quotient complete intersection Calabi-Yau threefolds with multiple line bundles, each with structure group U(1). These models are S- and T-dual to intersecting D-brane models in type IIA string theory. We find that the stable line bundles and Wilson...

Particle physics and cosmology with high-scale SUSY breaking in five-dimensional supergravity models

We discuss a high-scale SUSY breaking scenario with the wino dark matter in the five-dimensional supergravity model on S 1 /Z 2. The extra U(1) symmetries broken by the orbifold projection control the flavor structure of soft SUSY-breaking parameters as well as the Yukawa couplings, and a scalar component of the one of moduli multiplets, which arise from extra-dimensional...

Axion decay constants at special points in type II string theory

We propose the mechanism to disentangle the decay constant of closed string axion from the string scale in the framework of type II string theory on Calabi-Yau manifold. We find that the quantum and geometrical corrections in the prepotential that arise at some special points in the moduli space widen the window of axion decay constant. In particular, around the small complex...

Wavefunctions on magnetized branes in the conifold

We study wavefunctions on D7-branes with magnetic fluxes in the conifold. Since some supersymmetric embeddings of D-branes on the AdS 5 × T 1,1 geometry are known, we consider one of the embeddings, especially the spacetime filling D7-branes in which (a part of) the standard model is expected to be realized. The explicit form of induced metric on the D7-branes allows us to solve...

Moduli mediation without moduli-induced gravitino problem

We study the moduli-induced gravitino problem within the framework of the phenomenologically attractive mirage mediations. The huge amount of gravitino generated by the moduli decay can be successfully diluted by introducing an extra light modulus field which does not induce the supersymmetry breaking. Since the lifetime of extra modulus field becomes longer than usually...

Towards natural inflation from weakly coupled heterotic string theory

We propose natural inflation from the heterotic string theory on the “Swiss-Cheese” Calabi–Yau manifold with multiple $U(1)$ magnetic fluxes. Such multiple $U(1)$ magnetic fluxes stabilize the same number of the linear combination of the universal axion and Kähler axions, and one of the Kähler axions is identified as the inflaton. This axion decay constant can be determined by...

Natural inflation with and without modulations in type IIB string theory

We propose a mechanism for the natural inflation with and without modulation in the framework of type IIB string theory on toroidal orientifold or orbifold. We explicitly construct the stabilization potential of complex structure, dilaton and Kähler moduli, where one of the imaginary component of complex structure moduli becomes light which is identified as the inflaton. The...

Gauge coupling unification in SO(32) heterotic string theory with magnetic fluxes

We study $SO(32)$ heterotic string theory on a torus with magnetic fluxes. Non-vanishing fluxes can lead to non-universal gauge kinetic functions for $SU(3) \times SU(2) \times U(1)_Y$, which is an important feature of $SO(32)$ heterotic string theory in contrast to the $E_8\times E_8$ theory. It is found that the experimental values of gauge couplings are realized with $\mathcal...

Realistic three-generation models from SO(32) heterotic string theory

We search for realistic supersymmetric standard-like models from SO(32) heterotic string theory on factorizable tori with multiple magnetic fluxes. Three chiral ganerations of quarks and leptons are derived from the adjoint and vector representations of SO(12) gauge groups embedded in SO(32) adjoint representation. Massless spectra of our models also include Higgs fields, which...

The best time for surgery on a patient with recurrent pneumothorax and undetectable culprit lesions is at the exact time air leakage is discovered: a case report

Background One cause of recurrent spontaneous pneumothorax includes overlooking bullae during a previous surgery for pneumothorax; and the identification of the culprit lesions is necessary for prevention of recurrence. Case presentation A 28-year-old man was referred to our hospital because of spontaneous right-sided pneumothorax. He underwent video-assisted thoracoscopic...

Mediastinal myelolipoma showing gradual enlargement over 9 years: a case report

Background Myelolipoma is a rare benign tumor composed of mature adipose tissue and normal hematopoietic tissue. Although surgical resection has been recommended due to the potential of progressive enlargement, the natural history of mediastinal myelolipoma has not yet been described. Herein we report a surgically resected mediastinal myelolipoma showing gradual enlargement over...

One-stage operation for thoracic aortic arch aneurysm and left lung carcinoma: a case report

Background The simultaneous surgical treatment of thoracic aortic arch aneurysm (TAA) and lung carcinoma is extremely rare. Case presentation We report the simultaneous surgical treatment of TAA and squamous cell carcinoma of the lung in a 72-year-old Japanese man. We performed a one-stage operation that consisted of aortic arch replacement for aortic arch aneurysm with a 3...

Asymptomatic costal exostosis with thickening in the pericardium: a case report

Background Costal exostosis is a benign condition that sometimes requires emergent surgery because of associated hemothorax; in addition, there have been cases with malignant transformation to chondrosarcoma. Here, we describe an asymptomatic patient who underwent thoracoscopic resection for primary costal exostosis. Case presentation A 16-year-old male was found to have a bow...

Surgical treatment of chronic pulmonary aspergillosis using preventive latissimus dorsi muscle flaps

Background Surgery for chronic pulmonary aspergillosis is often technically risky. The choice of immediate thoracoplasty or muscle flap plombage to prevent postoperative space problems remains controversial. This study focused on the use of muscle flaps to prevent postoperative complications. Methods During an 8-year period (2004 to 2012), all patients surgically treated for...

Simultaneous resection of bilateral anomalous systemic supply to the basal segments of the lungs: a case report

Background Anomalous systemic arterial supply to the normal basal lung segments is a sequestration spectrum variant (Pryce type 1) that is distinguished from pulmonary sequestration by normal bronchopulmonary and parenchymal tissues. Case presentation A 33-year-old Japanese man was referred to our hospital because of an abnormal pulmonary shadow. Computed tomography showed two...

Treatment options for patients with large cell neuroendocrine carcinoma of the lung

Akira Iyoda Takashi Makino Satoshi Koezuka Hajime Otsuka Yoshinobu Hata Large cell neuroendocrine carcinoma (LCNEC) of the lung is categorized as a variant of large cell carcinomas, and LCNEC

Giant thymoma successfully resected via anterolateral thoracotomy: a case report

The appropriate surgical approach for a large mediastinal tumor is controversial. Median sternotomy is the standard approach for thymomas. We herein report the case of a giant thymoma, 13 cm in diameter, surgically resected via anterolateral incision. Subsequent thymectomy was performed via thoracoscopy. The resected specimen was a WHO type AB thymoma, Masaoka stage I, without...

The Higgs boson mass in a natural minimal supersymmetric standard model with nonuniversal gaugino masses at the grand unification theory scale

We identify a parameter region where the mass of the lightest CP-even Higgs boson resides at 124.4–126.8 GeV, and at the same time the degree of tuning a Higgsino-mass parameter (the so-called μ-parameter) is relaxed above 10% in the minimal supersymmetric standard model (MSSM) with soft supersymmetry breaking terms, by solving the full set of one-loop renormalization group...

Surgical treatment for severely damaged lung and pyothorax with bronchopleural fistula 9 years after induction chemoradiotherapy and bilobectomy

Here, we present a 54-year old man 9 years after induction chemoradiotherapy and subsequent lower bilobectomy for Stage IIIA lung cancer suffering late complications of pyothorax and bronchopleural fistula in a severely damaged lung. Open-window thoracostomy and subsequent completion pneumonectomy via median sternotomy and anterior thoracotomy were performed. Although sternal...

Haemothorax following bullectomy caused by a sharp edge of the Endoloop

A 22-year old man presented with a massive haemothorax 25 days after bullectomy for a spontaneous pneumothorax. Thoracoscopic surgery revealed ongoing bleeding from the chest wall caused by a sharp edge of the Endoloop Ligature (Ethicon Endo-Surgery) used to resect the remaining small part of the lung at the earlier staple bullectomy. The point where bleeding was occurring was...