meso-and dl-Bivalvane (Pentasecododecahedrane). Enantiomer Recognition during Reductive Coupling of Racemic and Chiral2,3-Dihydro-and Hexahydrotriquinacen-2-ones

Abstract: Pinacolic reduction of both optically pure and racemic hexahydrotriquinacen-2-one ( 6 ) proceeds with exo,exo carbon-carbon bond formation. Coupling of enantiomerically pure 6 produces diol 11 exclusively. Formation of comparable amounts of 11 and 12 from ( f ) -6 shows that the diastereomeric transition states involved are of comparable energy. Studies with chiral and racemic 2,3-dihydrotriquinacen-2-one (13) gave analogous results. The various 1,2-glycols are identified by their I3C N M R (symmetry is thereby revealed), 'H NMR (shielding of the endo protons at Cj and C3, by hydroxyl is witnessed), and ir spectra, in tandem with the method of synthesis. Conversion of the four diols to their thionocarbonates, and subsequent treatment with triethyl phosphite at the reflux temperature, provides the structurally related olefins stereospecifically. Catalytic hydrogenation of 17 provides dl-bivalvane (2), whereas reduction of 19 gives rise to the meso-bivalvane isomer 3. Other aspects of these transformations and conformational possibilities for 2 and 3 are discussed. The dodecahedron is one of the five perfect solids (the others are the tetrahedron, cube, octahedron, and icosahedron) and consequently has been a source of fascination for mathematicians since the time of Pythagoras and Plato. Only recently, however, has the dodecahedrane molecule attracted the attention of synthetic chemists. Notwithstanding, this (CH)2o polyhedron, which is endowed with most intriguing geometry, remains an unknown Although several approaches to dodecahedrane are currently under investigation in these laboratories, attention is focused specifically herein on the fundamental aspects of that scheme which involves effective "dimerization" of two triquinacene halves. The essence of,this concept is not new, it having been advanced earlier in singular form by Woodward, Fukunaga, and Kelly2 who viewed dodecahedrane as composed of two triquinacene subunits which when properly arranged might be coaxed into sixfold carbon-carbon bond formation as illustrated in 1. That efforts along this . 1 w line have consistently failed is not surprising, for the requirement of a highly ordered transition state which can maintain strict stereochemical control simultaneously (or nearly so) a t 12 trigonal carbon atoms is certain to be overwhelmingly endothermic. Moreover, the added restriction that all six bonds must form from the heavily encumbered endo direction at both termini will surely be most prohibitive. The further need to impinge any given T bond upon lobes of two different noninteracting' double bonds constitutes a process for which chemical analogy is lacking if concerted or metal catalyzedS8 Despite the disadvantages intrinsic to the above model, it is apparent that initial endo,endo coupling of two monomeric triquinacene units at C2 could go far in setting the stage for the ultimate construction of the desired polyhedron. Such a synthetic plan requires that there exist a reaction sequence which can lead readily to 2 as well as to more highly functionalized derivatives of this hydrocarbon. As we have noted earlier,5 a problem immediately presents itself, for the dissymmetry of the necessarily derivatized triquinacene precursors is such that a pair of coupling products having the structural features of 2 and 3 can arise if the monomer 2 3 --is a racemic mixture. Only when bonding between chiral triquinacenes results can it be guaranteed that unwanted formation of "dimer" 3 will be precluded. These conditions presuppose that reductive coupling of racemic triquinacenes will produce diastereomeric products with comparable facility. However, no information is available with which to formulate a reliable prediction. On a promising note, Touboul and Dana have recently reported that electrolytic reduction of racemic 4 proceeds in rigorously enantio-selective fashion with formation of cis-threocis diol 5 to the exclusion of the cis-erythro-cis and other w possible i~o m e r s .~ For the present study where 2,3-dihydrotriquinacen-2-one and its tetrahydro derivative serve as pivotal compounds, the prevailing steric factors are recognized to be generally inimical to bonding from the endo direction.I0 Because adherence to an exo,exo bonding scheme would necessitate ultimate inversion of configuration at C2 in both triquinacene segments, the synthetic methodology of choice should be one which is capable of achieving this transform readily. With these considerations in mind, convenient preparations of 2,3, and several related unsaturated congeners have presently been realized. In structural terms, 2 is recognized to be one of a number of possible pentasecododecahedranes

Design and Implementation of A CMOS Light Pulse Receiver Cell Array for Spatial Optical Communications

A CMOS light pulse receiver (LPR) cell for spatial optical communications is designed and evaluated by device simulations and a prototype chip implementation. The LPR cell consists of a pinned photodiode and four transistors. It works under sub-threshold region of a MOS transistor and the source terminal voltage which responds to the logarithm of the photo current are read out with a source follower circuit. For finding the position of the light spot on the focal plane, an image pixel array is embedded on the same plane of the LPR cell array. A prototype chip with 640 × 240 image pixels and 640 × 240 LPR cells is implemented with 0.18 μm CMOS technology. A proposed model of the transient response of the LPR cell agrees with the result of the device simulations and measurements. Both imaging at 60 fps and optical communication at the carrier frequency of 1 MHz are successfully performed. The measured signal amplitude and the calculation results of photocurrents show that the spatial optical communication up to 100 m is feasible using a 10 × 10 LED array

Annual report of Subcommittee for Examination of Causes of Maternal Death and their Prevention in Perinatology Committee, Japan Society of Obstetrics and Gynecology, 2013

As the fibrinogen level decreases early in atonic bleeding, early administration of FFP may be important as an initial approach to treat atonic bleeding.Amniotic fluid embolism is classified into 2 types, conventional type and uterus-type

The Quiescent Intracluster Medium in the Core of the Perseus Cluster

Clusters of galaxies are the most massive gravitationally-bound objects in the Universe and are still forming. They are thus important probes of cosmological parameters and a host of astrophysical processes. Knowledge of the dynamics of the pervasive hot gas, which dominates in mass over stars in a cluster, is a crucial missing ingredient. It can enable new insights into mechanical energy injection by the central supermassive black hole and the use of hydrostatic equilibrium for the determination of cluster masses. X-rays from the core of the Perseus cluster are emitted by the 50 million K diffuse hot plasma filling its gravitational potential well. The Active Galactic Nucleus of the central galaxy NGC1275 is pumping jetted energy into the surrounding intracluster medium, creating buoyant bubbles filled with relativistic plasma. These likely induce motions in the intracluster medium and heat the inner gas preventing runaway radiative cooling; a process known as Active Galactic Nucleus Feedback. Here we report on Hitomi X-ray observations of the Perseus cluster core, which reveal a remarkably quiescent atmosphere where the gas has a line-of-sight velocity dispersion of 164+/-10 km/s in a region 30-60 kpc from the central nucleus. A gradient in the line-of-sight velocity of 150+/-70 km/s is found across the 60 kpc image of the cluster core. Turbulent pressure support in the gas is 4% or less of the thermodynamic pressure, with large scale shear at most doubling that estimate. We infer that total cluster masses determined from hydrostatic equilibrium in the central regions need little correction for turbulent pressure.Comment: 31 pages, 11 Figs, published in Nature July

Factors Affecting Energy Metabolism and Prognosis in Patients with Amyotrophic Lateral Sclerosis.

Background/aims:Nutritional status is a factor affecting prognosis in patients with amyotrophic lateral sclerosis (ALS). Here, we aimed to clarify the factors associated with hypermetabolism and the prognosticators of ALS.Methods:Forty-two inpatients (22 men, 20 women) diagnosed with ALS according to the revised El-Escorial criteria were investigated. The following data were retrospectively analyzed: anthropometric measurements, blood biochemistry, disease severity, basal energy expenditure (BEE), resting energy expenditure (REE) measured by indirect calorimetry, spirometry, and bioelectrical impedance analysis. Single and multiple regression analysis was performed to examine factors affecting REE and metabolic changes (defined as the ratio of REE to fat-free mass [FFM]). The Kaplan-Meier method was used to examine factors associated with the occurrence of cumulative events (death or tracheostomy).Results:Among the 42 inpatients, REE was significantly higher than BEE, indicating hypermetabolism in ALS. Multiple regression analysis revealed that REE/FFM is strongly associated with the skeletal muscle index (-3.746 to -1.532, p < 0.0001) and percent forced vital capacity (%FVC) (-0.172 to -0.021, p = 0.013). Moreover, both the skeletal muscle index and %FVC were significant prognosticators associated with the occurrence of cumulative events.Conclusions:Energy metabolism was elevated in ALS, and respiratory status and muscle mass were associated with the hypermetabolism and poor prognosis. Adequate nutritional support may improve outcomes in ALS by preventing deterioration of respiratory status and reduction in muscle mass

Hitomi (ASTRO-H) X-ray Astronomy Satellite

The Hitomi (ASTRO-H) mission is the sixth Japanese x-ray astronomy satellite developed by a large international collaboration, including Japan, USA, Canada, and Europe. The mission aimed to provide the highest energy resolution ever achieved at E  >  2  keV, using a microcalorimeter instrument, and to cover a wide energy range spanning four decades in energy from soft x-rays to gamma rays. After a successful launch on February 17, 2016, the spacecraft lost its function on March 26, 2016, but the commissioning phase for about a month provided valuable information on the onboard instruments and the spacecraft system, including astrophysical results obtained from first light observations. The paper describes the Hitomi (ASTRO-H) mission, its capabilities, the initial operation, and the instruments/spacecraft performances confirmed during the commissioning operations for about a month

Increased E-selectin in hepatic ischemia-reperfusion injury mediates liver metastasis of pancreatic cancer

金沢大学医薬保健研究域医学系Several recent studies have reported that selectins are produced during ischemia-reperfusion injury, and that selectin ligands play an important role in cell binding to the endothelium and in liver metastasis. Portal clamping during pancreaticoduodenectomy with vessel resection for pancreatic head cancer causes hepatic ischemia-reperfusion injury, which might promote liver metastasis. We investigated the liver colonization of pancreatic cancer cells under hepatic ischemia-reperfusion and examined the involvement of E-selectin and its ligands. A human pancreatic cancer cell line (Capan-1) was injected into the spleen of mice after hepatic ischemia-reperfusion (I/R group). In addition, to investigate the effect of an anti-E-selectin antibody on liver colonization in the IR group, mice received an intraperitoneal injection of the anti-E-selectin antibody following hepatic ischemia-reperfusion and tumor inoculation (IR+Ab group). Four weeks later, mice were sacrificed and the number of tumor nodules on the liver was compared to mice without hepatic ischemia-reperfusion (control group). The incidence of liver metastasis in the I/R group was significantly higher (16 of 20, 80%) than that in the control group (6 of 20, 30%) (P<0.01). Moreover, mice in the I/R group had significantly more tumor nodules compared to those in the control group (median, 9.9 vs. 2.7 nodules) (P<0.01). In the I/R+Ab group, only 2 of 5 (40%) mice developed liver metastases. RT-PCR and southern blotting of the liver extracts showed that the expression of IL-1 and E-selectin mRNA after hepatic ischemia-reperfusion was significantly higher than the basal levels. Hepatic ischemia-reperfusion increases liver metastases and E-selectin expression in pancreatic cancer. These results suggest that E-selectin produced due to hepatic ischemia-reperfusion is involved in liver metastasis.Embargo Period 6 month

Research and Design of a Routing Protocol in Large-Scale Wireless Sensor Networks

无线传感器网络，作为全球未来十大技术之一，集成了传感器技术、嵌入式计算技术、分布式信息处理和自组织网技术，可实时感知、采集、处理、传输网络分布区域内的各种信息数据，在军事国防、生物医疗、环境监测、抢险救灾、防恐反恐、危险区域远程控制等领域具有十分广阔的应用前景。 本文研究分析了无线传感器网络的已有路由协议，并针对大规模的无线传感器网络设计了一种树状路由协议，它根据节点地址信息来形成路由，从而简化了复杂繁冗的路由表查找和维护，节省了不必要的开销，提高了路由效率，实现了快速有效的数据传输。 为支持此路由协议本文提出了一种自适应动态地址分配算——ADAR（AdaptiveDynamicAddre...As one of the ten high technologies in the future, wireless sensor network, which is the integration of micro-sensors, embedded computing, modern network and Ad Hoc technologies, can apperceive, collect, process and transmit various information data within the region. It can be used in military defense, biomedical, environmental monitoring, disaster relief, counter-terrorism, remote control of haz...学位：工学硕士院系专业：信息科学与技术学院通信工程系_通信与信息系统学号：2332007115216