Recovery of Small-Sized Blood Vessels in Ischemic Bone Under Static Magnetic Field

Effects of static magnetic field (SMF) on the vascularization in bone were evaluated using an ischemic bone model, where rat femoral artery was ligated. Magnetized and unmagnetized samarium–cobalt rods were implanted transcortically into the middle diaphysis of the ischemic femurs. Collateral circulation was evaluated by injection of microspheres into the abdominal aorta at the third week after ligation. It was found that the bone implanted with a magnetized rod showed a larger amount of trapped microspheres than that with an unmagnetized rod at the proximal and the distal region (P < 0.05 proximal region). There were no significant differences at the middle and the distal region. This tendency was similar to that of the bone mineral density in the SMF-exposed ischemic bone

Quantum key distribution with an efficient countermeasure against correlated intensity fluctuations in optical pulses

Quantum key distribution (QKD) allows two distant parties to share secret keys with the proven security even in the presence of an eavesdropper with unbounded computational power. Recently, GHz-clock decoy QKD systems have been realized by employing ultrafast optical communication devices. However, security loopholes of high-speed systems have not been fully explored yet. Here we point out a security loophole at the transmitter of the GHz-clock QKD, which is a common problem in high-speed QKD systems using practical band-width limited devices. We experimentally observe the inter-pulse intensity correlation and modulation-pattern dependent intensity deviation in a practical high-speed QKD system. Such correlation violates the assumption of most security theories. We also provide its countermeasure which does not require significant changes of hardware and can generate keys secure over 100 km fiber transmission. Our countermeasure is simple, effective and applicable to wide range of high-speed QKD systems, and thus paves the way to realize ultrafast and security-certified commercial QKD systems

Three-dimensional structure of monoanionic methionine-enkephalin: X-ray structure of tert-butyloxycarbonyl-Tyr-Gly-Gly-(4-bromo)Phe-Met-OH

AbstractThe conformation of tert-butyloxycarbonyl-Tyr-Gly-Gly-(4-bromo)Phe-Met-OH, as a monoanionic derivative of Met-enkephalin, was elucidated by X-ray crystal analysis. The molecule took an extended conformation which was bended at the Phe residue. The implication of the dimer formation caused by 4 intermolecular hydrogen bonds was discussed in the relation with the opiate receptor

Experience with pharyngo-laryngo-esophagectomy for carcinoma of the esophagus

Pharyngo-esophagectomy was clinically evaluated in 6 cases 1) Advanced cancer patients are included in this series, reflecting the delayed diagnosis. 2) The surgical indication of transplantation with free jejunum graft with vascular anastomosis is limited to localized cancer-bearing patients in cervical esopohagus. 3) In advanced cancer patients complete cervical node dissection in combination with potent chemotherapy is recommended for prevention of recurrence. Surgical outcome of the treatment for carcinoma of the esophagus has been improved more and more with advances in pre-and postoperative cares and surgical techniques. However, there are many problems confronting reconstruction following pharyngo-esophagectomy. To define this issue associated with surgical treatment of cervical esophageal carcinoma, this study was made on the basis of a result of our clinical experience

Increased Level of Pericardial Insulin-Like Growth Factor-1 in Patients With Left Ventricular Dysfunction and Advanced Heart Failure

ObjectivesTo test the hypothesis that the cardiac insulin-like growth factor-1 (IGF-1) system is up-regulated in the failing heart, we measured the pericardial (cardiac) and plasma (circulating) IGF-1 levels in coronary artery disease patients.BackgroundLocal IGF-1 systems are regulated differently from the systemic IGF-1 system. The cardiac IGF-1 system is up-regulated by the increased left ventricular (LV) wall stress. However, it remains unknown how this system is affected in LV dysfunction and heart failure.MethodsWe measured the plasma and pericardial fluid levels of IGF-1 and brain natriuretic peptide (BNP) in 87 coronary artery disease patients undergoing cardiac surgery, and examined their relationships with LV function and heart failure severity. The expressions of IGF-1 and IGF-1 receptor proteins were examined in endomyocardial biopsies obtained from other patients with normal or impaired LV function.ResultsThe pericardial IGF-1 and BNP levels were positively correlated with the plasma BNP level (both p < 0.001). The pericardial IGF-1 level was increased in heart failure patients, whereas the plasma IGF-1 level was rather decreased. The pericardial IGF-1 level was inversely correlated with the LV ejection fraction (p < 0.001), whereas the plasma IGF-1 level was not. Positive immunostaining for IGF-1 and IGF-1 receptor proteins was enhanced in myocardial biopsies from failing hearts compared with those from nonfailing hearts.ConclusionsThe pericardial IGF-1 level was increased in patients with LV dysfunction and heart failure, whereas the plasma IGF-1 level was decreased. These results may indicate that up-regulation of the cardiac IGF-1 system serves as a compensatory mechanism for LV dysfunction

Volume Expansion of Swiss-Cheese Universe

In order to investigate the effect of inhomogeneities on the volume expansion of the universe, we study modified Swiss-Cheese universe model. Since this model is an exact solution of Einstein equations, we can get an insight into non-linear dynamics of inhomogeneous universe from it. We find that inhomogeneities make the volume expansion slower than that of the background Einstein-de Sitter universe when those can be regarded as small fluctuations in the background universe. This result is consistent with the previous studies based on the second order perturbation analysis. On the other hand, if the inhomogeneities can not be treated as small perturbations, the volume expansion of the universe depends on the type of fluctuations. Although the volume expansion rate approaches to the background value asymptotically, the volume itself can be finally arbitrarily smaller than the background one and can be larger than that of the background but there is an upper bound on it.Comment: 22 pages, 7 figures, to be submitted to Phys. Rev.

CMB observations in LTB universes: Part I: Matching peak positions in the CMB spectrum

Acoustic peaks in the spectrum of the cosmic microwave background in spherically symmetric inhomogeneous cosmological models are studied. At the photon-baryon decoupling epoch, the universe may be assumed to be dominated by non-relativistic matter, and thus we may treat radiation as a test field in the universe filled with dust which is described by the Lema\^itre-Tolman-Bondi (LTB) solution. First, we give an LTB model whose distance-redshift relation agrees with that of the concordance $\Lambda$CDM model in the whole redshift domain and which is well approximated by the Einstein-de Sitter universe at and before decoupling. We determine the decoupling epoch in this LTB universe by Gamow's criterion and then calculate the positions of acoustic peaks. Thus obtained results are not consistent with the WMAP data. However, we find that one can fit the peak positions by appropriately modifying the LTB model, namely, by allowing the deviation of the distance-redshift relation from that of the concordance $\Lambda$CDM model at $z>2$ where no observational data are available at present. Thus there is still a possibility of explaining the apparent accelerated expansion of the universe by inhomogeneity without resorting to dark energy if we abandon the Copernican principle. Even if we do not take this extreme attitude, it also suggests that local, isotropic inhomogeneities around us may seriously affect the determination of the density contents of the universe unless the possible existence of such inhomogeneities is properly taken into account.Comment: 20 pages, 5 figure