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SUMMARY A new method of system identification of high-rise buildings is proposed in which high-rise buildings are represented by a shear-bending model. The method is devised to find the story shear and bending stiffnesses of a specific story from the horizontal floor accelerations. The special characteristic of the proposed method is to use a previously derived set of closed-form expressions for the story shear and bending stiffnesses in terms of the limited floor accelerations and to utilize a reduced shear-bending model with the same number of elements as the vibration recording points. In the proposed method, a difficulty of prediction of an unstable specific function in a low-frequency range can be overcome by introducing an ARX model. It is demonstrated that the shear-bending model can simulate the vibration records with a reasonable accuracy. It is shown further that the vibration records at two super high-rise buildings during the 2011 Tohoku (Japan) earthquake can be simulated with the proposed method including a technique of adding degrees of freedom between the vibration recording points. Copyright © 2012 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

SUMMARY A new method of system identification and damage detection of high-rise buildings is proposed in which high-rise buildings are represented by a shear-bending model. The method is devised to find the story shear and bending stiffnesses of a specific story from the floor accelerations just above and below the specific story. The special characteristic of the proposed method is to derive a set of closed-form expressions for the story shear and bending stiffnesses in terms of the limited floor accelerations. It is demonstrated that the method is suitable for the damage detection because the observation of floor accelerations at two stories is a simple task and damage detection can be performed directly from the change of a specific function of frequency at zero frequency. It is shown that a difficulty of prediction of the specific function in a low frequency range can be overcome by introducing an ARX (Auto-Regressive model with eXogenous input) model with constraints on transfer functions. Copyright © 2012 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

Abstract: The purpose of this paper is to propose a practical method for optimum design of non-linear oil dampers with relief mechanism installed in multi-story framed building structures. The optimum design problem is formulated so as to minimize the maximum interstory drift or maximum acceleration of top-story under design earthquakes in terms of a set of relief forces subject to an inequality constraint on the maximum ratio of the damping force to the relief force and an equality constraint on the sum of relief forces of oil dampers. The proposed method to solve the optimum design problem is a successive procedure which consists of two steps. The first step is a sensitivity analysis by using nonlinear time-history response analyses, and the second step is a modification of the set of relief forces based upon the sensitivity analysis. An advanced reduction method based on static condensation of the frame and energy equivalence transformation of oil dampers is proposed and introduced into the optimum procedure to reduce the computational load. Numerical examples are conducted to demonstrate the effectiveness and validity of the proposed design method. [Copyright &y& Elsevier]

The anatomy of the brachial plexus in the common hippopotamus ( Hippopotamus amphibius), which has not been previously reported, was first examined bilaterally in a newborn hippopotamus. Our observations clarified the following: (1) the brachial plexus comprises the fifth cervical ( C5) to first thoracic ( T1) nerves. These formed two trunks, C5- C6 and C7- T1; in addition, the axillary artery passed in between C6 and C7, (2) unique branches to the brachialis muscle and those of the lateral cutaneous antebrachii nerves ramified from the median nerve, (3) nerve fibre analysis revealed that these unique nerve branches from the median nerve were closely related and structurally similar to the musculocutaneous ( MC) nerve; however, they had changed course from the MC to the median nerve, and (4) this unique branching pattern is likely to be a common morphological feature of the brachial plexus in amphibians, reptiles and certain mammals. [ABSTRACT FROM AUTHOR]

Abstract: A direct method of physical-parameter system identification (SI) is developed in the case of containing noises at both floors above and below a specified story. To investigate the effect of the level of noise on the accuracy of identification, numerical simulations are performed in the frequency domain by generating two stationary random processes with the specified levels of power spectra. When the previous method of physical-parameter SI is applied to the case contaminated by noise at both floors, just above and below a specified story, it is difficult to evaluate the true stiffness and damping coefficients depending on the intensity. To overcome this difficulty, a new noise-bias compensation method is proposed which enables one to evaluate the intensity of noise in addition to the identification of story stiffness and damping. This method can be used in the case of small SN (Signal to Noise) ratios such as actual microtremor records. The effectiveness of the proposed method is demonstrated through a numerical example and an experiment using actual microtremor records for a reduced two-story model. [Copyright &y& Elsevier]

Abstract: A critical excitation problem for a rigid block is considered subjected to horizontal and vertical simultaneous base inputs. The rigid block is supported by a set of a horizontal spring and a dashpot and another set of two vertical springs and dashpots. These springs and dashpots represent the stiffness and damping of ground. The motion of the block consists of a horizontal–rotational (swaying–rocking) motion under a horizontal base input and a vertical motion under a vertical base input. Both the horizontal–rotational motion and the vertical motion contribute to the uplift of the edge of the block. Both the horizontal and vertical base inputs are to be described by two different non-stationary random processes with prescribed power spectra. A critical excitation problem is formulated in which the worst cross-spectrum and the corresponding cross-correlation function of the horizontal and vertical inputs are searched for the maximum mean squares response of the uplift. It is found that the real part (co-spectrum) and the imaginary part (quad-spectrum) of the worst cross-spectrum can be obtained by a devised algorithm including the interchange of the double maximization procedure for the time and cross-spectrum (functional: function of frequency) domains. [Copyright &y& Elsevier]

A detailed anatomical analysis of the left brachial plexus, composed of the fourth cervical to first thoracic spinal nerve roots, was performed in an adult male orangutan obtained from the Osaka Museum of Natural History. Although the medial and posterior cords fused into a common trunk, a nerve fibre analysis revealed that the cords were not actually connected. A superficial branch (Rs) running ventral to the musculocutaneous nerve (MC) and a deep branch (Rp) running dorsal to the MC innervated the coracobrachialis muscle, which was also innervated by coracobrachialis branches (Rmc) from the MC. Koizumi (1989 : Acta Anat. Nippon, 64, 18) reported that the Rmc and Rs innervated the superficial region of the coracobrachialis muscle corresponding to superficial coracobrachialis muscle in prosimians, whereas the Rp innervated the deep region. However, the detailed innervation of the coracobrachialis muscle in orangutans was not included in Koizumi and Sakai's (1995 : J. Anat. 186, 395) report. Our observations in an orangutan did not seem to support generalisation, because the common trunk of the Rp and Rmc appeared to innervate both the superficial and deep regions of the coracobrachialis muscle. Therefore, a nerve fibre analysis of the common trunk was performed as a detailed examination. The analysis confirmed that the Rp in the orangutan only innervated the deep region of the coracobrachialis muscle, similar to the innervation pattern seen in other apes and humans. [ABSTRACT FROM AUTHOR]

A new experimental system of base-isolated structures is proposed. There are two kinds of dampers usually used in the base-isolated buildings, one is a viscous-type damper and the other is an elastic-plastic hysteretic-type damper. The base-isolated structure with a viscous damper and that with an elastic-plastic hysteretic damper are compared in this paper. The viscous damper is modeled by a mini piston and the elastic-plastic hysteretic damper is modeled by a low yield-point steel. The capacity of both dampers is detennined so that the dissipated energies are equivalent at a specified deformation. When the capacity of both dampers is determined according to this criterion, it is shown that the response of the base-isolated structure with the elastic-plastic hysteretic damper is larger than that with the viscous damper. This characteristic is demonstrated through the comparison of the bound of the aspect ratio. It is shown that the bound of aspect ratio for the base-isolated structure with the elastic-plastic hysteretic damper is generally smaller than that with the viscous damper. When the base-isolated structure is subjected to long-duration input, the mechanical property of the elastic-plastic hysteretic damper deteriorates and the response of the base-isolated structure including that damper becomes larger than that with the viscous damper. The effect of this change of material properties on the response of the base-isolated structure is also investigated. [ABSTRACT FROM AUTHOR]

SUMMARY Fundamental mechanisms of earthquake response reduction in building structures with inertial mass dampers are investigated. The inertial mass damper is effective with respect to relative acceleration between two nodes. The influence of inertial mass dampers on the ground-motion input can be expressed by the influence coefficient vector to be multiplied on the ground-motion acceleration in the right-hand side of the equations of motion. It is shown that, when an inertial mass damper is taken out from one story, the component of the influence coefficient vector above that story becomes 1. This means that, if an inertial mass damper is taken out from one story, the inertial mass dampers above that story do not influence the input acceleration above that story. This observation is supported by the closed-form expression of the influence coefficient vector. The mechanism of earthquake response reduction is also discussed from the viewpoint of earthquake input energy. It is shown that the earthquake input energy under an acceleration input with a constant Fourier spectrum depends on the influence coefficient vector. Finally, the characteristics of earthquake response reduction via inertial mass dampers are presented for three recorded ground motions. Copyright © 2011 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

The seizure threshold 2 (SZT2) gene encodes a large, highly conserved protein that is associated with epileptogenesis. In mice, Szt2 is abundantly expressed in the central nervous system. Recently, biallelic SZT2 mutations were found in 7 patients (from 5 families) presenting with epileptic encephalopathy with dysmorphic features and/or non‐syndromic intellectual disabilities. In this study, we identified by whole‐exome sequencing compound heterozygous SZT2 mutations in 3 patients with early‐onset epileptic encephalopathies. Six novel SZT2 mutations were found, including 3 truncating, 1 splice site and 2 missense mutations. The splice‐site mutation resulted in skipping of exon 20 and was associated with a premature stop codon. All individuals presented with seizures, severe developmental delay and intellectual disabilities with high variability. Brain MRIs revealed a characteristic thick and short corpus callosum or a persistent cavum septum pellucidum in each of the 2 cases. Interestingly, in the third case, born to consanguineous parents, had unexpected compound heterozygous missense mutations. She showed microcephaly despite the other case and previous ones presenting with macrocephaly, suggesting that SZT2 mutations might affect head size. [ABSTRACT FROM AUTHOR]

Abstract: In the afternoon of March 11, 2011, the eastern Japan was severely attacked by the 2011 off the Pacific coast of Tohoku earthquake (the Great East Japan earthquake). Nearly 30,000 people were killed or are still missing by that earthquake and the ensuing monster tsunami as of April 11, 2011. This paper reports some aspects of this devastating earthquake which hit an advanced country in seismic resistant design. It has been reported that long-period ground motions were induced in Tokyo, Nagoya and Osaka. The properties of these long-period ground motions are discussed from the viewpoint of critical excitation and the seismic behavior of two steel buildings of 40 and 60 stories subjected to the long-period ground motion recorded at Shinjuku, Tokyo is determined and discussed. This paper also reports the effectiveness of visco-elastic dampers like high-hardness rubber dampers in the reduction of responses of super high-rise buildings subjected to such long-period ground motions. The response reduction rate is investigated in detail in addition to the maximum response reduction. In December 2010 before this earthquake, simulated long-period ground motions for earthquake resistant design of high-rise buildings were provided in three large cities in Japan (Tokyo, Nagoya and Osaka) and nine areas were classified. Two 40-story steel buildings (slightly flexible and stiff) are subjected to these long-period ground motions in those nine areas for the detailed investigation of response characteristics of super high-rise buildings in various areas. [Copyright &y& Elsevier]

Examines a case of myelodysplastic syndrome (MDS) with pancytopenia in a 69-year-old patient. Clinical manifestations; Results of diagnostic procedures; Effect of biscoclaurine alkaloids on MDS.