194 research outputs found

    Quantitative Impact Analysis of the Centralization of Firms in the Tokyo Metropolitan Area Considering Firm-to-Firm Trade Networks

    Get PDF
    When a firm makes a location decision, it considers only its own transportation costs and ignores the transportation costs of its trading partners, resulting in inefficient sparce locations of firms. Since Beckmann (1976), it has been known that such inefficient sparse locations occur in the canonical land use models with interactions between agents, and this externality is referred to as locational externality by Kanamoto (1990). We quantitatively analyze the scale of locational externalities using micro data of the listed firms located in the Tokyo metropolitan area and firm-to-firm trade network data. We show (1) which trade patterns involve locational externalities, (2) the ratio of trade generating locational externalities as a percentage of total trade is about 24%, (3) the transfer of a randomly-chosen 5% of firms to two business centers, Marunouchi and Shibuya, generates median external benefits of 1.9% and 1.3% in the total industry in terms of value-added, respectively, (4) benefits vary according to industry and location (e.g., about 10% in the case of firms located far from the centers, and about 5% in the case of firms in the information and communications industry)

    Reducing Hemorrhagic Complication by Dabigatran Via Neurovascular Protection After Recanalization With Tissue Plasminogen Activator in Ischemic Stroke of Rat

    Get PDF
    This study assesses the risks and benefits of tissue plasminogen activator (tPA) treatment under oral anticoagulation with dabigatran compared with warfarin or vehicle control in transient middle cerebral artery occlusion (tMCAO). After pretreatment with warfarin (0.2 mg/kg/day), dabigatran (20 mg/kg/day), or vehicle (0.5% carboxymethyl cellulose sodium salt) for 7 days, tMCAO was induced for 120 min, followed by reperfusion and tPA (10 mg/kg/10 ml). Clinical parameters, including cerebral infarction volume, hemorrhagic volume, and blood coagulation, were examined. At 24 hr after reperfusion, markers for the neurovascular unit at the peri-ischemic lesion were immunohistochemically examined in brain sections, and MMP-9 activity was measured by zymography. Paraparesis and intracerebral hemorrhage volume were significantly improved in the dabigatran-pretreated group compared with the warfarin-pretreated group. A marked dissociation between astrocyte foot processes and the basal lamina or pericyte was observed in the warfarin-pretreated group, which was greatly improved in the dabigatran-pretreated group. Furthermore, a remarkable activation of MMP-9 in the ipsilateral warfarin-pretreated rat brain was greatly reduced in dabigatran-pretreated rats. The present study reveals that the mechanism of intracerebral hemorrhage with warfarin-pretreatment plus tPA in ischemic stroke rats is the dissociation of the neurovascular unit, including the pericyte. Neurovascular protection by dabigatran, which was first shown in this study, could partially explain the reduction in hemorrhagic complication by dabigatran reported from clinical study

    Multiple emission lines of Hα\alpha emitters at z2.3z \sim 2.3 from the broad and medium-band photometry in the ZFOURGE Survey

    Full text link
    We present a multiple emission lines study of \sim1300 Hα\alpha emitters (HAEs) at z2.3z \sim 2.3 in the ZFOURGE survey. In contrast to the traditional spectroscopic method, our sample is selected based on the flux excess in the ZFOURGE-KsK_s broad-band data relative to the best-fit stellar continuum. Using the same method, we also extract the strong diagnostic emission lines for these individual HAEs: [OIII]λλ4959,5007\lambda\lambda4959,5007, [OII]λλ3726,3729\lambda\lambda3726,3729. Our measurements exhibit good consistency with those obtained from spectroscopic surveys. We investigate the relationship between the equivalent widths (EWs) of these emission lines and various galaxy properties, including stellar mass, stellar age, star formation rate (SFR), specific SFR (sSFR), ionization states (O32). We have identified a discrepancy between between HAEs at z2.3z\sim2.3 and typical local star-forming galaxy observed in the SDSS, suggesting the evolution of lower gas-phase metallicity (ZZ) and higher ionization parameters (UU) with redshift. Notably, we have observed a significant number of low-mass HAEs exhibiting exceptionally high EW[OIII]EW_{\mathrm{[OIII]}}. Their galaxy properties are comparable to those of extreme objects, such as extreme O3 emitters (O3Es) and Lyα\alpha emitters (LAEs) at z23z\simeq2-3. Considering that these characteristics may indicate potential strong Lyman continuum (LyC) leakage, higher redshift anaglogs of the low-mass HAEs could be significant contributors to the cosmic reionization. Further investigations on this particular population are required to gain a clearer understanding of galaxy evolution and cosmic reionization.Comment: 24 pages, 13 figures, submitted to Ap

    Thrombolysis with Low-Dose Tissue Plasminogen Activator 3–4.5 h After Acute Ischemic Stroke in Five Hospital Groups in Japan

    Get PDF
    Clinical data from Japan on the safety and real-world outcomes of alteplase (tPA) thrombolysis in the extended therapeutic window are lacking. The aim of this study was to assess the safety and real-world outcomes of tPA administered within 3-4.5 h of stroke onset. The study comprised consecutive acute ischemic stroke patients (n = 177) admitted across five hospitals between September 2012 and August 2014. Patients received intravenous tPA within <3 or 3-4.5 h of stroke onset. Endovascular therapy was used for tPA-refractory patients. In the 3-4.5 h subgroup (31.6 % of patients), tPA was started 85 min later than the <3 h group (220 vs. 135 min, respectively). However, outcome measures were not significantly different between the <3 and 3-4.5 h subgroups for recanalization rate (67.8 vs. 57.1 %), symptomatic intracerebral hemorrhage (2.5 vs. 3.6 %), modified Rankin Scale score of 0-1 at 3 months (36.0 vs. 23.4 %), and mortality (6.9 vs. 8.3 %). We present data from 2005 to 2012 using a therapeutic window <3 h showing comparable results. tPA following endovascular therapy with recanalization might be superior to tPA only with recanalization (81.0 vs. 59.1 %). Compared with administration within 3 h of ischemic stroke onset, tPA administration within 3-4.5 h of ischemic stroke onset in real-world stroke emergency settings at multiple sites in Japan is as safe and has the same outcomes

    Impact of laparoscopic surgery on short‐term and long‐term outcomes in elderly obese patients with colon cancer

    Get PDF
    [Background] Laparoscopic surgery is reported to be useful in obese or elderly patients with colon cancer, who are at increased risk of postoperative complications because of comorbidities and physical decline. However, its usefulness is less clear in patients who are both elderly and obese and may be at high risk of complications. [Methods] Data for obese patients (body mass index ≥25) who underwent laparoscopic or open surgery for stage II or III colon cancer between January 2009 and December 2013 were collected by the Japan Society of Laparoscopic Colorectal Surgery. Surgical outcomes, postoperative complications, and relapse-free survival (RFS) were compared between patients who underwent open surgery and those who underwent laparoscopic surgery according to whether they were elderly (≥70 y) or nonelderly (<70 y). [Results] Data of 1549 patients (elderly, n = 598; nonelderly, n = 951) satisfied the selection criteria for analysis. Length of stay was shorter and surgical wound infection was less common in elderly obese patients who underwent laparoscopic surgery than in those underwent open surgery. There were no significant between-group differences in overall complications, anastomotic leakage, ileus/small bowel obstruction, or RFS. There were also no significant differences in RFS after laparoscopic surgery according to patient age. [Conclusion] Laparoscopic surgery is safe in elderly obese patients with colon cancer and does not worsen their prognosis. There was no significant difference in the effectiveness of laparoscopic surgery between obese patients who were elderly and those who were nonelderly

    Fast parametric two-qubit gates with suppressed residual interaction using the second-order nonlinearity of a cubic transmon

    Get PDF
    We demonstrate fast two-qubit gates using a parity-violated superconducting qubit consisting of a capacitively shunted asymmetric Josephson-junction loop under a finite magnetic flux bias. The second-order nonlinearity manifesting in the qubit enables the interaction with a neighboring single-junction transmon qubit via first-order interqubit sideband transitions with Rabi frequencies up to 30 MHz. Simultaneously, the unwanted static longitudinal (ZZ) interaction is eliminated with ac Stark shifts induced by a continuous microwave drive near resonant to the sideband transitions. The average fidelities of the two-qubit gates are evaluated with randomized benchmarking as 0.971, 0.958, and 0.962 for CZ, iswap, and swap gates, respectively

    Environmental impact on star-forming galaxies in a z0.9z \sim 0.9 cluster during course of galaxy accretion

    Full text link
    Galaxies change their properties as they assemble into clusters. In order to understand the physics behind that, we need to go back in time and observe directly what is occurring in galaxies as they fall into a cluster. We have conducted a narrow-band and JJ-band imaging survey on a cluster CL1604-D at z=0.923z=0.923 using a new infrared instrument SWIMS installed at the Subaru Telescope. The narrow-band filter, NB1261, matches to Hα\alpha emission from the cluster at z=0.923z=0.923. Combined with a wide range of existing data from various surveys, we have investigated galaxy properties in and around this cluster in great detail. We have identified 27 Hα\alpha emitters associated with the cluster. They have significant overlap with MIPS 24μ\mum sources and are located exclusively in the star forming regime on the rest-frame UVJUVJ diagram. We have identified two groups of galaxies near the cluster in the 2D spatial distribution and the phase-space diagram, which are likely to be in-falling to the cluster main body. We have compared various physical properties of star forming galaxies, such as specific star formation rates (burstiness) and morphologies (merger) as a function of environment; cluster center, older group, younger group, and the field. As a result, a global picture has emerged on how the galaxy properties are altered as they assemble into a denser region. This includes the occurrence of mergers, enhancement of star formation activity, excursion to the dusty starburst phase, and eventual quenching to a passive phase.Comment: 19 pages, 15 figures. Accepted for publication in ApJ. Error bars in Table 2 correcte
    corecore