2,099 research outputs found

    Korean Immigrants’ Perceptions of Library Services and Library Multicultural Programs for Asian Communities Before and During COVID-19

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    This study explored 141 Korean immigrant parents’ use of local libraries to enhance their families’ social and cultural capital and adjust to the host country. We searched resources in Korean, and multicultural programs planned for the public and immigrants, Asian immigrants in particular, at two libraries before and during COVID-19. Parents reported dissatisfaction with library services because of language barriers (38%) and the lack of Korean resources (38%) and cultural programs (25%). Except for 18 books and 24 e-resources, no library resources in Korean were published after 2008. Before COVID-19, one multicultural program was offered for children. At Branches B and C, the number of adult programs related to Asian culture decreased to 0% from 6% and increased to 3% from 0%, respectively, during COVID-19, when hate crimes against Asians increased by 77%. The respondents’ concerns about the lack of programs supporting their adjustment and fostering multicultural dialogue were validated

    Turboelectric Distributed Propulsion in a Hybrid Wing Body Aircraft

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    The performance of the N3-X, a 300 passenger hybrid wing body (HWB) aircraft with turboelectric distributed propulsion (TeDP), has been analyzed to see if it can meet the 70% fuel burn reduction goal of the NASA Subsonic Fixed Wing project for N+3 generation aircraft. The TeDP system utilizes superconducting electric generators, motors and transmission lines to allow the power producing and thrust producing portions of the system to be widely separated. It also allows a small number of large turboshaft engines to drive any number of propulsors. On the N3-X these new degrees of freedom were used to (1) place two large turboshaft engines driving generators in freestream conditions to maximize thermal efficiency and (2) to embed a broad continuous array of 15 motor driven propulsors on the upper surface of the aircraft near the trailing edge. That location maximizes the amount of the boundary layer ingested and thus maximizes propulsive efficiency. The Boeing B777-200LR flying 7500 nm (13890 km) with a cruise speed of Mach 0.84 and an 118100 lb payload was selected as the reference aircraft and mission for this study. In order to distinguish between improvements due to technology and aircraft configuration changes from those due to the propulsion configuration changes, an intermediate configuration was included in this study. In this configuration a pylon mounted, ultra high bypass (UHB) geared turbofan engine with identical propulsion technology was integrated into the same hybrid wing body airframe. That aircraft achieved a 52% reduction in mission fuel burn relative to the reference aircraft. The N3-X was able to achieve a reduction of 70% and 72% (depending on the cooling system) relative to the reference aircraft. The additional 18% - 20% reduction in the mission fuel burn can therefore be attributed to the additional degrees of freedom in the propulsion system configuration afforded by the TeDP system that eliminates nacelle and pylon drag, maximizes boundary layer ingestion (BLI) to reduce inlet drag on the propulsion system, and reduces the wake drag of the vehicle

    Enhancement of seawater corrosion resistance in copper using acetone-derived graphene coating

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    We show that acetone-derived graphene coating can effectively enhance the corrosion efficiency of copper (Cu) in a seawater environment (0.5-0.6 M (???3.0-3.5%) sodium chloride). By applying a drop of acetone (???20 ??l cm-2) on Cu surfaces, rapid thermal annealing allows the facile and rapid synthesis of graphene films on Cu surfaces with a monolayer coverage of almost close to ???100%. Under optimal growth conditions, acetone-derived graphene is found to have a relatively high crystallinity, comparable to common graphene grown by chemical vapor deposition. The resulting graphene-coated Cu surface exhibits 37.5 times higher corrosion resistance as compared to that of mechanically polished Cu. Further, investigation on the role of graphene coating on Cu surfaces suggests that the outstanding corrosion inhibition efficiency (IE) of 97.4% is obtained by protecting the underlying Cu against the penetration of both dissolved oxygen and chlorine ions, thanks to the closely spaced atomic structure of the graphene sheets. The increase of graphene coating thickness results in the enhancement of the overall corrosion IE up to ???99%, which can be attributed to the effective blocking of the ionic diffusion process via grain boundaries. Overall, our results suggest that the acetone-derived graphene film can effectively serve as a corrosion-inhibiting coating in the seawater level and that it may have a promising role to play for potential offshore coating.close0

    Ciliated muconodular papillary tumor of the lung: The risk of false-positive diagnosis in frozen section

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    AbstractCiliated muconodular papillary tumor (CMPT) is newly-defined low-grade malignant tumor, characterized as papillary tumor consisting of ciliated columnar, goblet, and basal cells. We present one case of pulmonary peripheral neoplasm misdiagnosed as mucinous adenocarcinoma. Pathologic findings showed, centrally, cystic papillary growth consisting of ciliated columnar, goblet, and basal cells, and peripherally, some tumor cells spread along the adjacent alveolar walls, in a lepidic fashion, and floating in pool of mucin. Tumor cells had bland nuclei, and no mitotic activity was observed. This had been initially misdiagnosed as mucinous adenocarcinoma in frozen section. We reviewed previous articles as well as permanent and frozen slides. In conclusion, in order to reduce the possibility of false positives, it is important to be aware that CMPT is a rare form of peripheral mucin-producing tumor with characteristic histologic findings

    Dirichlet Branes of the Covariant Open Supermembrane in AdS_4 x S^7 and AdS_7 x S^4

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    We discuss an open supermembrane theory in the AdS_4 x S^7 and AdS_7 x S^4 backgrounds. The possible Dirichlet branes of an open supermembrane are classified by analyzing the covariant Wess-Zumino term. All of the allowed configurations are related to those on the pp-wave background via the Penrose limit.Comment: 16 pages, LaTeX, some clarifications and references adde

    The Bell Laboratories (13)CO Survey: Longitude-Velocity Maps

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    A survey is presented of the Galactic plane in the J=1-0 transition of (13)CO. About 73,000 spectra were obtained with the 7 m telescope at Bell Laboratories over a ten-year period. The coverage of survey is (l, b) = (-5 to 117, -1 to +1), or 244 square degrees, with a grid spacing of 3' for |b| < 0.5, and a grid spacing of 6' for |b| > 0.5. The data presented here have been resampled onto a 3' grid. For 0.68 km/s channels, the rms noise level of the survey is 0.1 K on the TR∗T_R^* scale. The raw data have been transformed into FITS format, and all the reduction processes, such as correcting for emission in the reference positions, baseline removal and interpolation were conducted within IRAF using the FCRAO task package and additional programs. The reduced data are presented here in the form of longitude-velocity color maps at each latitude. These data allow identification and classification of molecular clouds with masses in excess of ~ 1,000 solar masses throughout the first quadrant of the Galaxy. Spiral structure is manifested by the locations of the largest and brightest molecular clouds.Comment: 23 pages, 7 figures, ApJS submitted (out of 41 frames of Figure4, only one is included becaue of size limit

    Notes on D-branes of Type IIB String on AdS_5 x S^5

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    We promote a study of D-branes of type IIB string on the AdS_5 x S^5 background. The possible D-branes preserving half of supersymmetries were classified up to and including the fourth order of fermionic variable \th in our previous work [hep-th/0310228]. In this paper we show that our classification is still valid even at the full order of \th. This proof supplements our previous results and completes the classification of D-branes in the type IIB string theory on the AdS_5 x S^5.Comment: 11 pages, no figures, LaTe

    Open string derivation of winding states in thermal noncommutative field theories

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    The `winding state' behavior appears in the two-loop nonplanar contribution to the partition function in thermal noncommutative field theories. We derive this feature directly from the purely open string theory analysis in the presence of the constant background BB-field; we compute the two-loop partition function for worldsheets with a handle and a boundary when the time direction of the Euclideanized target space is compactified. In contrast to the closed-string-inspired approach, it is not necessary to add infinite number of extra degrees of freedom. Furthermore, we find a piece of supporting evidence toward the conjecture that, in the UV limit, the noncommutativity parameter plays the role of the effective string scale in noncommutative field theories.Comment: 12 pages, late

    Phospholipase D1 Mediates AMP-Activated Protein Kinase Signaling for Glucose Uptake

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    Glucose homeostasis is maintained by a balance between hepatic glucose production and peripheral glucose utilization. In skeletal muscle cells, glucose utilization is primarily regulated by glucose uptake. Deprivation of cellular energy induces the activation of regulatory proteins and thus glucose uptake. AMP-activated protein kinase (AMPK) is known to play a significant role in the regulation of energy balances. However, the mechanisms related to the AMPK-mediated control of glucose uptake have yet to be elucidated.Here, we found that AMPK-induced phospholipase D1 (PLD1) activation is required for (14)C-glucose uptake in muscle cells under glucose deprivation conditions. PLD1 activity rather than PLD2 activity is significantly enhanced by glucose deprivation. AMPK-wild type (WT) stimulates PLD activity, while AMPK-dominant negative (DN) inhibits it. AMPK regulates PLD1 activity through phosphorylation of the Ser-505 and this phosphorylation is increased by the presence of AMP. Furthermore, PLD1-S505Q, a phosphorylation-deficient mutant, shows no changes in activity in response to glucose deprivation and does not show a significant increase in (14)C-glucose uptake when compared to PLD1-WT. Taken together, these results suggest that phosphorylation of PLD1 is important for the regulation of (14)C-glucose uptake. In addition, extracellular signal-regulated kinase (ERK) is stimulated by AMPK-induced PLD1 activation through the formation of phosphatidic acid (PA), which is a product of PLD. An ERK pharmacological inhibitor, PD98059, and the PLD inhibitor, 1-BtOH, both attenuate (14)C-glucose uptake in muscle cells. Finally, the extracellular stresses caused by glucose deprivation or aminoimidazole carboxamide ribonucleotide (AICAR; AMPK activator) regulate (14)C-glucose uptake and cell surface glucose transport (GLUT) 4 through ERK stimulation by AMPK-mediated PLD1 activation.These results suggest that AMPK-mediated PLD1 activation is required for (14)C-glucose uptake through ERK stimulation. We propose that the AMPK-mediated PLD1 pathway may provide crucial clues to understanding the mechanisms involved in glucose uptake
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