Families of bosonic suppression laws beyond the permutation symmetry principle

Exact cancellation of quantum amplitudes in multiphoton interferences with Fock states at input, the so-called suppression or zero transmission laws generalizing the Hong-Ou-Mandel dip, are useful tool in quantum information and computation. It was recently suggested that all bosonic suppression laws follow from a common permutation symmetry in the input quantum state and the unitary matrix of interferometer. By using the recurrence relations for interference of Fock states, we find a wealth of suppression laws on the beamsplitter and tritter which are not explained by the permutation symmetry principle. Our results reveal that in interference with Fock states on unitary multiports there are whole families of suppression laws for arbitrary total number of bosons even on asymmetric unitary multiports, beyond the previously formulated permutation symmetry principle.Comment: 19 pages, 3 figure

iPS細胞に由来する生存未分化細胞の形態学的解析

Induced pluripotent stem (iPS) cells possess pluripotency and self-renewal ability. Therefore, iPS cells are expected to be useful in regenerative medicine. However, iPS cells form malignant immature teratomas after transplantation into animals, even after differentiation induction. It has been suggested that undifferentiated cells expressing Nanog that remain after differentiation induction are responsible for teratoma formation. Various methods of removing these undifferentiated cells have therefore been investigated, but few methods involve morphological approaches, which may induce less cell damage. In addition, for cells derived from iPS cells to be applied in regenerative medicine, they must be alive. However, detailed morphological analysis of live undifferentiated cells has not been performed. For the above reasons, we assessed the morphological features of live undifferentiated cells remaining after differentiation induction as a basic investigation into the clinical application of iPS cells. As a result, live undifferentiated cells remaining after differentiation induction exhibited a round or oval cytoplasm about 12 μm in diameter and a nucleus. They exhibited nucleo-cytoplasmic (N/C) ratio of about 60% and eccentric nuclei, and they possessed partially granule-like structures in the cytoplasm and prominent nucleoli. Although they were similar to iPS cells, they were smaller than live iPS cells. Furthermore, very small cells were present among undifferentiated cells after differentiation induction. These results suggest that the removal of undifferentiated cells may be possible using the morphological features of live iPS cells and undifferentiated cells after differentiation induction. In addition, this study supports safe regenerative medicine using iPS cells.九州保健福祉大学平成29年

Structure analysis of Zn-Mg-Ho icosahedral quasicrystal by modified Rietveld method using ellipsoid and sphere windows

A structure analysis of Zn-Mg-Ho icosahedral quasicrystal was carried out by the powder X-ray diffraction method using synchrotron radiation (Lambda=0.73490 A) at SPring-8. The intensity distribution was analyzed by the Rietveld method modified for an icosahedral quasicrystal, in which simplified models were assumed: ellipsoid and spherical windows were assumed at five crystallographic sites in a F-type hypercubic unit cell. The analysis revealed the presence of an almost perfect Penrose tiling with edge length 5.20 A. The vertices are occupied alternatively by Zn and Mg, and almost all of the edge centers of the Penrose rhombohedra are occupied by 0.8Zn and 0.2Mg. Ho and Mg atoms tend to be present on the body diagonal of the prolate rhombohedra. Good agreement between the measured and calculated intensity distribution using the simplified model suggests the applicability and the limitation of structure analysis using the powder X-ray diffraction method.Comment: 10 pages, 3 tables, 3 figure

Mechanisms of temporomandibular joint-osteoarthrosis (TMJ-OA) : Biomechanical, histological and biochemical evidences

Condylar resorption in the TMJ or TMJ-OA has been experienced occasionally in daily orthodontic practice and recognized to induce substantial influences on craniofacial morphology and the treatment outcomes. This study was designed to investigate the mechanisms of TMJ-OA by means of biomechanical, histological and biochemical approaches. Biomechanical study with finite element stress analysis revealed an existence of large compressive stresses in the anterior, middle and lateral areas on the condyle and prominent increases in the compressive stresses in association with vertical discrepancy of the craniofacial skeleton. Such skeletal discrepancy, simulated in growing rats by placing a metal plate on the upper molars, produced a decrease in the thickness of cartilage layers and an increase in the number of TRAP-positive cells, both of which lead to degenerative changes in the articular cartilage of the mandibular condyle. Furthermore, excessive tensile stresses, applied to articular chondrocytes with use of the Flexercell Strain Unit, induced an imbalance between matrix metalloproteinases(MMPs) and tissue inhibitors of matrix metalloproteinases(TIMPs), which is assumed to induce lower resistance to external stimuli and degenerative changes leading to the resorption of bone and cartilage. It is thus shown that excessive or imbalanced mechanical loading on the TMJ components from occlusal and skeletal discrepancies induce various degenerative responses of cartilaginous tissues and articular chondrocytes, leading to the destruction of bone or cartilage in TMJ-OA

Variations in Clinical Findings of Patients with Identical Tuberous Sclerosis Gene Mutations

Colorectal carcinogenesis involves environmental factors and genetic predispositions. Recent studies have suggested the associations between colorectal neoplasm and functional polymorphism of matrix metalloproteinases (MMPs) and cytokine genes. In this study, we analyzed polymorphisms of MMPs and tumor necrosis factor (TNF)-alpha genes, focusing on the susceptibility to colorectal neoplasm and the tumor progression. The subjects were 186 patients (95 men and 91 women) who underwent total colonoscopy, and were classified into cancer, adenoma and non-neoplasm (control) groups of 47, 72 and 67 patients, respectively. The polymorphisms at the MMP-2 ?1306C/T, MMP-3 ?1171 5A/6A, MMP-7 ?181A/G, MMP-9 ?1562C/T and TNF-alpha ?308G/A loci were analyzed. Regarding background factors, significant differences were found in the age, sex ratio and alcohol-drinking and cigarette-smoking histories in the adenoma and cancer groups, compared to those in the control group. On these factors-adjusted logistic regression analysis of polymorphisms and disease susceptibility, no significant difference was noted in the frequency of any polymorphism in the adenoma and cancer groups, compared to those in the control group. The analysis of the involvement of polymorphisms in tumor progression in the adenoma and cancer groups revealed that the odds ratio for the MMP-3 5A allele was significantly higher in the cancer group (2.74; 95% confidence interval = 1.11?6.74, P = 0.02). The polymorphisms of MMP genes and TNF-alpha genes were not associated with the susceptibility to colorectal neoplasm, but the involvement of the MMP-3 5A allele in the progression of adenoma to cancer was suggested

Asymmetric responses of East Asian currencies to the US dollar depreciation for reducing the US current account deficits

In this paper, we investigate responses of East Asian currencies to the US dollar depreciation in the near future. First, we show that a significant depreciation of the US dollar will be necessary in order to reduce the current account deficits. Second, we show that the responses of the East Asian currencies to a sudden and sharp depreciation of the US dollar will differ with countries because of the different degree of linkages of the East Asian currencies to the US dollar. Based on the above analyses, a regional coordination of the exchange rate policy is necessary to the East Asian countries to response appropriately to a possible depreciation of the US dollar in the near future

Tuberous Sclerosis 2 Gene Is Expressed at High Levels in Specific Types of Neurons in the Mouse Brain

Tuberous sclerosis (TSC) is an autosomal dominant disorder characterized by mental retardation, epilepsy and hamartomatous growth in many tissues. The gene (TSC2) encoding a tumor suppressor protein whose mutations cause TSC, has been demonstrated to be expressed at high levels in the adult and developing brain, raising the question of whether or not the TSC2 gene product has unique roles in differentiation related to cytoskeletal interactions within the central nervous system, in addition to a tumor suppressor function. To determine the expression of TSC2 in functionally distinct neuron types of the mouse brain, we carried out in situ hybridization with digoxigenin-labeled riboprobes for the detection of TSC2 mRNA. High levels of the TSC2 gene were in neurons of the pyramidal and dentate granular layer in the hippocampus, cerebellar Purkinje cells, neurons of the piriform cortex, motor neurons in the medulla and interneurons in the striatum, while intermediate levels were in cortical neurons, striatal neurons, septal neurons, thalamic neurons and neurons in the substantia nigra compacta. Thus, the high expression of the TSC2 gene has restricted distribution in specific neuronal types which are characterized by well-developed dendrites and rich in use-dependent long-term changes in synaptic efficacy. These results suggest that the function of the TSC2 gene product may be involved on a cellular basis in neuronal plasticity and relevant to mental retardation observed in TSC patients