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Radiative impact of mixing state of black carbon aerosol in Asian outflow
The radiative impact of the mixing state of black carbon (BC) aerosol is investigated in Asian outflow. The mixing state and size distribution of BC aerosol were measured with a ground-based single-particle soot photometer at a remote island (Fukue) in Japan in spring 2007. The mass concentration of BC in Asian continental air masses reached 0.5 μg m-3, with a mass median diameter of 200-220 nm. The median value of the shell/core diameter ratio increased to ∼1.6 in Asian continental and maritime air masses with a core diameter of 200 mn, while in free tropospheric and Japanese air masses it was 1.3-1.4. On the basis of theoretical calculations using the size distribution and mixing state of BC aerosol, scattering and absorption properties of PM1 aerosols were calculated under both dry and ambient conditions, considering the hygroscopic growth of aerosols. It was estimated that internal mixing enhanced the BC absorption by a factor of 1.5-1.6 compared to external mixing. The calculated absorption coefficient was 2-3 times higher in Asian continental air masses than in clean air. Coatings reduced the single-scattering albedo (SSA) of PM1 aerosol by 0.01 -0.02, which indicates the importance of the mixing state of BC aerosol in evaluating its radiative influence. The SSA was sensitive to changes in air mass type, with a value of ∼0.98 in Asian continental air masses and ∼0.95 in Japanese and free tropospheric air masses under ambient conditions. Copyright 2008 by the American Geophysical Union
Encircled Angular Flux Representation of the Modal Power Distribution and its Behavior in a Step Index Multimode Fiber
The optical properties of in-line optical components inserted at the input to a multimode optical fiber (MMF) strongly affect the propagating modal power distribution (MPD). To realize stable systems with predictable reproducible performance and to encourage widespread use of MMF systems, improvements to the system design process and to the characterization process need to be made and new interface standards need to be defined. To this end, we have developed a new reproducible MPD measurement and representation together with its theoretical definition. By modifying the encircled flux (EF) representation, which is based on the near-field pattern of a graded-index multimode optical fiber (GI-MMF), we define the encircled angular flux (EAF) for step-index multimode optical fibers (SI-MMFs) based on their far-field patterns (FFPs). Using a SI-MMF, which is used for low cost short distance interconnects, as an example, we show the changes in the MPD along the fiber, reveal an unusual insertion loss-increasing phenomenon due to the evanescent tails of the core modes extending into the cladding, and characterize the equilibrium mode distribution (EMD) in the fiber. The EAF representation enables these phenomena to be quantified. We also propose an EAF template that consists of the target EMD and its tolerance. If device system designers use the EAF template to set the launch conditions, they can perform a fair assessment of the components, and they can design the system performance even if some components are replaced with others from a different supplier manufactured by a different method. We call this concept “Total MPD Management.
Surgical Results of Patients with Peritoneal Carcinomatosis Treated with Cytoreductive Surgery Using a New Technique Named Aqua Dissection
During 2004 to 2011, 81, 420, and 166 patients with colorectal cancer (CRC), epithelial appendiceal neoplasm (APN), and gastric cancer (GC) with PC were treated with cytoreductive surgery (CRS) plus perioperative chemotherapy. CRS was performed by peritonectomy techniques using an aqua dissection. Results. Complete cytoreduction was done in 62/81 (76.5%), 228/420 (54.3%), and 101/166 (60.8%) of patients with CRC, APN, and GC. The main reasons of incomplete resections were involvement of all peritoneal regions and diffuse involvement of small bowel. The incidence (64%, 302/470) of CC-0 resection after introduction of an aqua dissection was significantly higher than before (42%, 82/197). A total of 41 (6.1%) patients died postoperatively. Major complication (grade 3-4 complications) occurred in 126 patients (18.9%). A reoperation was necessary in 36 patients (5.4%). By the multivariate analysis, PCI scores capable of serving as thresholds for favorable versus poor prognosis in each group and CC scores demonstrated as the independent prognostic factors. Conclusions. Peritonectomy using an aqua dissection improves the incidence of complete cytoreduction, and improves the survival of patients with PC. Patients with PCI larger than the threshold values should be treated with chemotherapy to improve the incidences of complete cytoreduction
Chains of N=2, D=4 heterotic/type II duals
We report on a search for heterotic strings that are dual candidates of
type II compactifications on Calabi-Yau threefolds described as
fibrations. We find many new heterotic duals by using standard orbifold
techniques. The associated type II compactifications fall into chains in which
the proposed duals are heterotic compactifications related one another by a
sequential Higgs mechanism. This breaking in the heterotic side typically
involves the sequence , while in the type II side the weights of the complex hypersurfaces and the
structure of the quotient singularities also follow specific patterns.Comment: Latex, 21 pages, 2 table
Primary retroperitoneal mullerian adenocarcinoma
Mullerian tumors are extremely rare malignancies in the retroperitoneum. We report a case of a 46-year old woman who presented with an eight year history of lower abdominal mass. Ultrasonography (US) and computed tomography (CT) demonstrated a 15×10 cm cystic mass in the left lower retroperitoneum. As serial percutaneous needle aspiration cytology was negative for malignancy, she was observed for seven years. Eleven months ago, the mass was excised. The histopathology was reported as mucinous adenocarcinoma of the retroperitoneum. Six cycles of intraperitoneal (IP) chemotherapy was administered during the last six months after diagnosis of recurrence by aspiration cytology and high serum tumor markers (CEA, CA19-9). A few days ago, positron emission tomographic (PET) scanning showed evidence of local recurrence and single vertebral metastasis, so she was admitted again for systemic chemotherapy. Meticulous revision of additional sections of the tumor revealed papillary, serous, mucinous, and endometrioid subtypes of the mullerian adenocarcinoma. To our knowledge, there has been no similar case described in the literature
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