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860 results on '"K. Y. LEE"'

1. Reconstruction of 400 GeV/c proton interactions with the SHiP-charm project

Author

SHiP Collaboration, C. Ahdida, A. Akmete, R. Albanese, A. Alexandrov, F. Alicante, J. Alt, S. Aoki, G. Arduini, J. J. Back, F. Baaltasar Dos Santos, F. Bardou, G. J. Barker, M. Battistin, J. Bauche, A. Bay, V. Bayliss, C. Betancourt, I. Bezshyiko, O. Bezshyyko, D. Bick, S. Bieschke, A. Blanco, J. Boehm, M. Bogomilov, I. Boiarska, K. Bondarenko, W. M. Bonivento, J. Borburgh, A. Boyarsky, R. Brenner, D. Breton, A. Brignoli, V. Büscher, A. Buonaura, S. Buontempo, S. Cadeddu, M. Calviani, M. Campanelli, M. Casolino, D. Centanni, N. Charitonidis, P. Chau, J. Chauveau, K.-Y. Choi, A. Chumakov, V. Cicero, M. Climescu, A. Conaboy, L. Congedo, K. Cornelis, M. Cristinziani, A. Crupano, G. M. Dallavalle, A. Datwyler, N. D’Ambrosio, G. D’Appollonio, R. de Asmundis, J. De Carvalho Saraiva, G. De Lellis, M. de Magistris, A. De Roeck, M. De Serio, D. De Simone, A. Di Crescenzo, L. Di Giulio, C. Dib, H. Dijkstra, L. A. Dougherty, V. Drohan, A. Dubreuil, O. Durhan, M. Ehlert, E. Elikkaya, F. Fabbri, F. Fedotovs, M. Ferrillo, M. Ferro-Luzzi, R. A. Fini, H. Fischer, P. Fonte, C. Franco, M. Fraser, R. Fresa, R. Froeschl, T. Fukuda, G. Galati, J. Gall, L. Gatignon, V. Gentile, B. Goddard, L. Golinka-Bezshyyko, A. Golutvin, P. Gorbounov, V. Gorkavenko, A. L. Grandchamp, E. Graverini, J.-L. Grenard, D. Grenier, A. M. Guler, G. J. Haefeli, C. Hagner, H. Hakobyan, I. W. Harris, E. van Herwijnen, C. Hessler, A. Hollnagel, B. Hosseini, G. Iaselli, A. Iuliano, R. Jacobsson, D. Joković, M. Jonker, I. Kadenko, V. Kain, B. Kaiser, C. Kamiscioglu, K. Kershaw, G. Khoriauli, Y. G. Kim, N. Kitagawa, J.-W. Ko, K. Kodama, D. I. Kolev, M. Komatsu, A. Kono, S. Kormannshaus, I. Korol, A. Korzenev, V. Kostyukhin, E. Koukovini Platia, S. Kovalenko, H. M. Lacker, M. Lamont, O. Lantwin, A. Lauria, K. S. Lee, K. Y. Lee, N. Leonardo, J.-M. Lévy, V. P. Loschiavo, L. Lopes, E. Lopez Sola, F. Lyons, V. Lyubovitskij, J. Maalmi, A.-M. Magnan, Y. Manabe, M. Manfredi, S. Marsh, A. M. Marshall, P. Mermod, A. Miano, S. Mikado, A. Mikulenko, D. A. Milstead, A. Montanari, M. C. Montesi, K. Morishima, Y. Muttoni, N. Naganawa, M. Nakamura, T. Nakano, P. Ninin, A. Nishio, S. Ogawa, J. Osborne, M. Ovchynnikov, N. Owtscharenko, P. H. Owen, P. Pacholek, B. D. Park, A. Pastore, M. Patel, A. Perillo-Marcone, G. L. Petkov, K. Petridis, J. Prieto Prieto, A. Prota, A. Quercia, A. Rademakers, A. Rakai, T. Rawlings, F. Redi, A. Reghunath, S. Ricciardi, M. Rinaldesi, Volodymyr Rodin, Viktor Rodin, P. Robbe, A. B. Rodrigues Cavalcante, H. Rokujo, T. Rovelli, O. Ruchayskiy, T. Ruf, F. Sanchez Galan, P. Santos Diaz, A. Sanz Ull, O. Sato, J. S. Schliwinski, W. Schmidt-Parzefall, M. Schumann, N. Serra, S. Sgobba, O. Shadura, M. Shaposhnikov, L. Shchutska, H. Shibuya, L. Shihora, S. Shirobokov, S. B. Silverstein, S. Simone, R. Simoniello, G. Soares, J. Y. Sohn, A. Sokolenko, E. Solodko, L. Stoel, M. E. Stramaglia, D. Sukhonos, Y. Suzuki, S. Takahashi, J. L. Tastet, I. Timiryasov, V. Tioukov, D. Tommasini, M. Torii, N. Tosi, D. Treille, R. Tsenov, G. Vankova-Kirilova, F. Vannucci, P. Venkova, V. Venturi, S. Vilchinski, Heinz Vincke, Helmut Vincke, C. Visone, S. van Waasen, R. Wanke, P. Wertelaers, O. Williams, J.-K. Woo, M. Wurm, S. Xella, D. Yilmaz, A. U. Yilmazer, C. S. Yoon, and J. Zimmerman

Subjects
Astrophysics, QB460-466, Nuclear and particle physics. Atomic energy. Radioactivity, QC770-798
Abstract

Abstract The SHiP-charm project was proposed to measure the associated charm production induced by 400 GeV/c protons in a thick target, including the contribution from cascade production. An optimisation run was performed in July 2018 at CERN SPS using a hybrid setup. The high resolution of nuclear emulsions acting as vertex detector was complemented by electronic detectors for kinematic measurements and muon identification. Here we present first results on the analysis of nuclear emulsions exposed in the 2018 run, which prove the capability of reconstructing proton interaction vertices in a harsh environment, where the signal is largely dominated by secondary particles produced in hadronic and electromagnetic showers within the lead target.

Published
2024
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2. Measurement of the muon flux at the SND@LHC experiment

Author

R. Albanese, A. Alexandrov, F. Alicante, A. Anokhina, T. Asada, C. Battilana, A. Bay, C. Betancourt, D. Bick, R. Biswas, A. Blanco Castro, V. Boccia, M. Bogomilov, D. Bonacorsi, W. M. Bonivento, P. Bordalo, A. Boyarsky, S. Buontempo, M. Campanelli, T. Camporesi, V. Canale, A. Castro, D. Centanni, F. Cerutti, M. Chernyavskiy, K. -Y. Choi, S. Cholak, F. Cindolo, M. Climescu, A. P. Conaboy, G. M. Dallavalle, D. Davino, P. T. de Bryas, G. De Lellis, M. De Magistris, A. De Roeck, A. De Rújula, M. De Serio, D. De Simone, A. Di Crescenzo, R. Donà, O. Durhan, F. Fabbri, F. Fedotovs, M. Ferrillo, M. Ferro-Luzzi, R. A. Fini, A. Fiorillo, R. Fresa, W. Funk, F. M. Garay Walls, A. Golovatiuk, A. Golutvin, E. Graverini, A. M. Guler, V. Guliaeva, G. J. Haefeli, C. Hagner, J. C. Helo Herrera, E. van Herwijnen, P. Iengo, S. Ilieva, A. Infantino, A. Iuliano, R. Jacobsson, C. Kamiscioglu, A. M. Kauniskangas, E. Khalikov, S. H. Kim, Y. G. Kim, G. Klioutchnikov, M. Komatsu, N. Konovalova, S. Kuleshov, H. M. Lacker, O. Lantwin, F. Lasagni Manghi, A. Lauria, K. Y. Lee, K. S. Lee, S. Lo Meo, V. P. Loschiavo, S. Marcellini, A. Margiotta, A. Mascellani, A. Miano, A. Mikulenko, M. C. Montesi, F. L. Navarria, S. Ogawa, N. Okateva, M. Ovchynnikov, G. Paggi, B. D. Park, A. Pastore, A. Perrotta, D. Podgrudkov, N. Polukhina, A. Prota, A. Quercia, S. Ramos, A. Reghunath, T. Roganova, F. Ronchetti, T. Rovelli, O. Ruchayskiy, T. Ruf, M. Sabate Gilarte, Z. Sadykov, M. Samoilov, V. Scalera, W. Schmidt-Parzefall, O. Schneider, G. Sekhniaidze, N. Serra, M. Shaposhnikov, V. Shevchenko, T. Shchedrina, L. Shchutska, H. Shibuya, S. Simone, G. P. Siroli, G. Sirri, G. Soares, J. Y. Sohn, O. J. Soto Sandoval, M. Spurio, N. Starkov, I. Timiryasov, V. Tioukov, F. Tramontano, C. Trippl, E. Ursov, A. Ustyuzhanin, G. Vankova-Kirilova, V. Verguilov, N. Viegas Guerreiro Leonardo, C. Vilela, C. Visone, R. Wanke, E. Yaman, C. Yazici, C. S. Yoon, E. Zaffaroni, and J. Zamora Saa

Subjects
Astrophysics, QB460-466, Nuclear and particle physics. Atomic energy. Radioactivity, QC770-798
Abstract

Abstract The Scattering and Neutrino Detector at the LHC (SND@LHC) started taking data at the beginning of Run 3 of the LHC. The experiment is designed to perform measurements with neutrinos produced in proton-proton collisions at the LHC in an energy range between 100 GeV and 1 TeV. It covers a previously unexplored pseudo-rapidity range of $$7.2

Published
2024
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3. Results and Perspectives from the First Two Years of Neutrino Physics at the LHC by the SND@LHC Experiment

Author

D. Abbaneo, S. Ahmad, R. Albanese, A. Alexandrov, F. Alicante, K. Androsov, A. Anokhina, T. Asada, C. Asawatangtrakuldee, M. A. Ayala Torres, C. Battilana, A. Bay, A. Bertocco, C. Betancourt, D. Bick, R. Biswas, A. Blanco Castro, V. Boccia, M. Bogomilov, D. Bonacorsi, W. M. Bonivento, P. Bordalo, A. Boyarsky, S. Buontempo, M. Campanelli, T. Camporesi, V. Canale, A. Castro, D. Centanni, F. Cerutti, M. Chernyavskiy, K.-Y. Choi, S. Cholak, F. Cindolo, M. Climescu, A. P. Conaboy, G. M. Dallavalle, D. Davino, P. T. de Bryas, G. De Lellis, M. De Magistris, A. De Roeck, A. De Rújula, M. De Serio, D. De Simone, A. Di Crescenzo, D. Di Ferdinando, R. Donà, O. Durhan, F. Fabbri, F. Fedotovs, M. Ferrillo, M. Ferro-Luzzi, R. A. Fini, A. Fiorillo, R. Fresa, W. Funk, F. M. Garay Walls, A. Golovatiuk, A. Golutvin, E. Graverini, A. M. Guler, V. Guliaeva, G. J. Haefeli, C. Hagner, J. C. Helo Herrera, E. van Herwijnen, P. Iengo, S. Ilieva, A. Infantino, A. Iuliano, R. Jacobsson, C. Kamiscioglu, A. M. Kauniskangas, E. Khalikov, S. H. Kim, Y. G. Kim, G. Klioutchnikov, M. Komatsu, N. Konovalova, S. Kuleshov, L. Krzempek, H. M. Lacker, O. Lantwin, F. Lasagni Manghi, A. Lauria, K. Y. Lee, K. S. Lee, S. Lo Meo, V. P. Loschiavo, S. Marcellini, A. Margiotta, A. Mascellani, F. Mei, A. Miano, A. Mikulenko, M. C. Montesi, F. L. Navarria, W. Nuntiyakul, S. Ogawa, N. Okateva, M. Ovchynnikov, G. Paggi, B. D. Park, A. Pastore, A. Perrotta, D. Podgrudkov, N. Polukhina, A. Prota, A. Quercia, S. Ramos, A. Reghunath, T. Roganova, F. Ronchetti, T. Rovelli, O. Ruchayskiy, T. Ruf, M. Sabate Gilarte, Z. Sadykov, M. Samoilov, V. Scalera, W. Schmidt-Parzefall, O. Schneider, G. Sekhniaidze, N. Serra, M. Shaposhnikov, V. Shevchenko, T. Shchedrina, L. Shchutska, H. Shibuya, S. Simone, G. P. Siroli, G. Sirri, G. Soares, J. Y. Sohn, O. J. Soto Sandoval, M. Spurio, N. Starkov, J. Steggemann, I. Timiryasov, V. Tioukov, F. Tramontano, C. Trippl, E. Ursov, A. Ustyuzhanin, G. Vankova-Kirilova, G. Vasquez, V. Verguilov, N. Viegas Guerreiro Leonardo, C. Vilela, C. Visone, R. Wanke, E. Yaman, Z. Yang, C. Yazici, C. S. Yoon, E. Zaffaroni, and J. Zamora Saa

Subjects
SND@LHC, neutrino, neutrino interactions, electron neutrino, muon neutrino, tau neutrino, Mathematics, QA1-939
Abstract

After rapid approval and installation, the SND@LHC Collaboration was able to gather data successfully in 2022 and 2023. Neutrino interactions from νμs originating at the LHC IP1 were observed. Since muons constitute the major background for neutrino interactions, the muon flux entering the acceptance was also measured. To improve the rejection power of the detector and to increase the fiducial volume, a third Veto plane was recently installed. The energy resolution of the calorimeter system was measured in a test beam. This will help with the identification of νe interactions that can be used to probe charm production in the pseudo-rapidity range of SND@LHC (7.2 < η < 8.4). Events with three outgoing muons have been observed and are being studied. With no vertex in the target, these events are very likely from muon trident production in the rock before the detector. Events with a vertex in the detector could be from trident production, photon conversion, or positron annihilation. To enhance SND@LHC’s physics case, an upgrade is planned for HL-LHC that will increase the statistics and reduce the systematics. The installation of a magnet will allow the separation of νμ from ν¯μ

Published
2024
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4. Microwave Dielectric and Reflection Analysis on Pure and Adulterated Trigona Honey and Honey Gold

Author

E. M. Cheng, K. Y. Lee, S. F. Khor, N. F. Mohd Nasir, C. W. S. R. Mohamad, N. A. Abdul Aziz, E. Z. Mohd Tarmizi, and S. A. Baharuddin

Subjects
honey, sucrose, water, dielectric, reflection, Electrical engineering. Electronics. Nuclear engineering, TK1-9971
Abstract

Honey adulteration is common in food industry, as it provides cheaper alternative for user to consume honey. However, it has been abused by industry runners with unsavory practices. It leads to business fraudulency. Pure honey is very precious due to its powerful health-giving properties. It rises attention of beekeeper, wholesaler, food manufacturer, retailer and consumer because this issue has been sensationally reported in media mass. Enforcement of law is initiated to mitigate the abuse and fraudulency. Apart from that, it motivates scientists, technologists and engineers to strive for an effective solution. Microwave sensing method is well known in agricultural product and food. Hence, dielectric and reflection response is explored for the potential of development of instrumentation system in gauging edible honeys. In this work, the dielectric and reflection measurement were conducted using Agilent E8362B PNA Network Analyzer in conjunction with Agilent 85070E Performance Probe from 0.5 GHz to 4.5 GHz. Dielectric and reflection measurement were conducted to investigate its dielectric behavior and mismatch impedance due to water and sucrose content in honey. It can be noticed that dielectric constant, ε’ decreases when frequency increases. In the meantime, ε’ decreases with increment of water and sucrose content for Honey Gold and Trigona Honey. Meanwhile, for water adulterated Honey Gold and Trigona Honey, loss factor, ε” decrease when frequencies increases. In addition, ε” decreases when water content ( 36% and ( 43% for Honey Gold and Trigona Honey, respectively. It can be found that at 1 GHz to 4 GHz, ε” increases when sucrose content increases which applicable for Honey Gold and Trigona Honey. In reflection measurement, magnitude of reflection coefficient, |Γ| decrease when frequency increases for all percentage of water and sucrose content for both honeys. Withal, phase, -φ increases as frequency increases for both water adulterated honeys. -φ varies insignificantly when sucrose content increases for both sucrose adulterated honeys.

Published
2022

5. Light-triggered cardiac microphysiological model

Author

V. Vurro, K. Shani, H. A. M. Ardoña, J. F. Zimmerman, V. Sesti, K. Y. Lee, Q. Jin, C. Bertarelli, K. K. Parker, and G. Lanzani

Subjects
Biotechnology, TP248.13-248.65, Medical technology, R855-855.5
Abstract

Light is recognized as an accurate and noninvasive tool for stimulating excitable cells. Here, we report on a non-genetic approach based on organic molecular phototransducers that allows wiring- and electrode-free tissue modulation. As a proof of concept, we show photostimulation of an in vitro cardiac microphysiological model mediated by an amphiphilic azobenzene compound that preferentially dwells in the cell membrane. Exploiting this optical based stimulation technology could be a disruptive approach for highly resolved cardiac tissue stimulation.

Published
2023
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6. The SHiP experiment at the proposed CERN SPS Beam Dump Facility

Author

C. Ahdida, A. Akmete, R. Albanese, J. Alt, A. Alexandrov, A. Anokhina, S. Aoki, G. Arduini, E. Atkin, N. Azorskiy, J. J. Back, A. Bagulya, F. Baaltasar Dos Santos, A. Baranov, F. Bardou, G. J. Barker, M. Battistin, J. Bauche, A. Bay, V. Bayliss, A. Y. Berdnikov, Y. A. Berdnikov, C. Betancourt, I. Bezshyiko, O. Bezshyyko, D. Bick, S. Bieschke, A. Blanco, J. Boehm, M. Bogomilov, I. Boiarska, K. Bondarenko, W. M. Bonivento, J. Borburgh, A. Boyarsky, R. Brenner, D. Breton, A. Brignoli, V. Büscher, A. Buonaura, S. Buontempo, S. Cadeddu, M. Calviani, M. Campanelli, M. Casolino, N. Charitonidis, P. Chau, J. Chauveau, A. Chepurnov, M. Chernyavskiy, K.-Y. Choi, A. Chumakov, M. Climescu, A. Conaboy, L. Congedo, K. Cornelis, M. Cristinziani, A. Crupano, G. M. Dallavalle, A. Datwyler, N. D’Ambrosio, G. D’Appollonio, R. de Asmundis, J. De Carvalho Saraiva, G. De Lellis, M. de Magistris, A. De Roeck, M. De Serio, D. De Simone, L. Dedenko, P. Dergachev, A. Di Crescenzo, L. Di Giulio, C. Dib, H. Dijkstra, V. Dmitrenko, L. A. Dougherty, A. Dolmatov, S. Donskov, V. Drohan, A. Dubreuil, O. Durhan, M. Ehlert, E. Elikkaya, T. Enik, A. Etenko, O. Fedin, F. Fedotovs, M. Ferrillo, M. Ferro-Luzzi, K. Filippov, R. A. Fini, H. Fischer, P. Fonte, C. Franco, M. Fraser, R. Fresa, R. Froeschl, T. Fukuda, G. Galati, J. Gall, L. Gatignon, G. Gavrilov, V. Gentile, B. Goddard, L. Golinka-Bezshyyko, A. Golovatiuk, V. Golovtsov, D. Golubkov, A. Golutvin, P. Gorbounov, D. Gorbunov, S. Gorbunov, V. Gorkavenko, M. Gorshenkov, V. Grachev, A. L. Grandchamp, E. Graverini, J.-L. Grenard, D. Grenier, V. Grichine, N. Gruzinskii, A. M. Guler, Yu. Guz, G. J. Haefeli, C. Hagner, H. Hakobyan, I. W. Harris, E. van Herwijnen, C. Hessler, A. Hollnagel, B. Hosseini, M. Hushchyn, G. Iaselli, A. Iuliano, R. Jacobsson, D. Joković, M. Jonker, I. Kadenko, V. Kain, B. Kaiser, C. Kamiscioglu, D. Karpenkov, K. Kershaw, M. Khabibullin, E. Khalikov, G. Khaustov, G. Khoriauli, A. Khotyantsev, Y. G. Kim, V. Kim, N. Kitagawa, J.-W. Ko, K. Kodama, A. Kolesnikov, D. I. Kolev, V. Kolosov, M. Komatsu, A. Kono, N. Konovalova, S. Kormannshaus, I. Korol, I. Korol’ko, A. Korzenev, E. Koukovini Platia, S. Kovalenko, I. Krasilnikova, Y. Kudenko, E. Kurbatov, P. Kurbatov, V. Kurochka, E. Kuznetsova, H. M. Lacker, M. Lamont, O. Lantwin, A. Lauria, K. S. Lee, K. Y. Lee, N. Leonardo, J.-M. Lévy, V. P. Loschiavo, L. Lopes, E. Lopez Sola, F. Lyons, V. Lyubovitskij, J. Maalmi, A.-M. Magnan, V. Maleev, A. Malinin, Y. Manabe, A. K. Managadze, M. Manfredi, S. Marsh, A. M. Marshall, A. Mefodev, P. Mermod, A. Miano, S. Mikado, Yu. Mikhaylov, A. Mikulenko, D. A. Milstead, O. Mineev, M. C. Montesi, K. Morishima, S. Movchan, Y. Muttoni, N. Naganawa, M. Nakamura, T. Nakano, S. Nasybulin, P. Ninin, A. Nishio, B. Obinyakov, S. Ogawa, N. Okateva, J. Osborne, M. Ovchynnikov, N. Owtscharenko, P. H. Owen, P. Pacholek, B. D. Park, A. Pastore, M. Patel, D. Pereyma, A. Perillo-Marcone, G. L. Petkov, K. Petridis, A. Petrov, D. Podgrudkov, V. Poliakov, N. Polukhina, J. Prieto Prieto, M. Prokudin, A. Prota, A. Quercia, A. Rademakers, A. Rakai, F. Ratnikov, T. Rawlings, F. Redi, A. Reghunath, S. Ricciardi, M. Rinaldesi, Volodymyr Rodin, Viktor Rodin, P. Robbe, A. B. Rodrigues Cavalcante, T. Roganova, H. Rokujo, G. Rosa, O. Ruchayskiy, T. Ruf, V. Samoylenko, V. Samsonov, F. Sanchez Galan, P. Santos Diaz, A. Sanz Ull, O. Sato, E. S. Savchenko, J. S. Schliwinski, W. Schmidt-Parzefall, M. Schumann, N. Serra, S. Sgobba, O. Shadura, A. Shakin, M. Shaposhnikov, P. Shatalov, T. Shchedrina, L. Shchutska, V. Shevchenko, H. Shibuya, L. Shihora, S. Shirobokov, A. Shustov, S. B. Silverstein, S. Simone, R. Simoniello, M. Skorokhvatov, S. Smirnov, G. Soares, J. Y. Sohn, A. Sokolenko, E. Solodko, N. Starkov, L. Stoel, M. E. Stramaglia, D. Sukhonos, Y. Suzuki, S. Takahashi, J. L. Tastet, P. Teterin, S. Than Naing, I. Timiryasov, V. Tioukov, D. Tommasini, M. Torii, D. Treille, R. Tsenov, S. Ulin, E. Ursov, A. Ustyuzhanin, Z. Uteshev, L. Uvarov, G. Vankova-Kirilova, F. Vannucci, P. Venkova, V. Venturi, I. Vidulin, S. Vilchinski, Heinz Vincke, Helmut Vincke, C. Visone, K. Vlasik, A. Volkov, R. Voronkov, S. van Waasen, R. Wanke, P. Wertelaers, O. Williams, J.-K. Woo, M. Wurm, S. Xella, D. Yilmaz, A. U. Yilmazer, C. S. Yoon, Yu. Zaytsev, A. Zelenov, J. Zimmerman, and SHiP Collaboration

Subjects
Astrophysics, QB460-466, Nuclear and particle physics. Atomic energy. Radioactivity, QC770-798
Abstract

Abstract The Search for Hidden Particles (SHiP) Collaboration has proposed a general-purpose experimental facility operating in beam-dump mode at the CERN SPS accelerator to search for light, feebly interacting particles. In the baseline configuration, the SHiP experiment incorporates two complementary detectors. The upstream detector is designed for recoil signatures of light dark matter (LDM) scattering and for neutrino physics, in particular with tau neutrinos. It consists of a spectrometer magnet housing a layered detector system with high-density LDM/neutrino target plates, emulsion-film technology and electronic high-precision tracking. The total detector target mass amounts to about eight tonnes. The downstream detector system aims at measuring visible decays of feebly interacting particles to both fully reconstructed final states and to partially reconstructed final states with neutrinos, in a nearly background-free environment. The detector consists of a 50 $$\mathrm { \,m}$$ m long decay volume under vacuum followed by a spectrometer and particle identification system with a rectangular acceptance of 5 m in width and 10 m in height. Using the high-intensity beam of 400 $$\,\mathrm {GeV}$$ GeV protons, the experiment aims at profiting from the $$4\times 10^{19}$$ 4 × 10 19 protons per year that are currently unexploited at the SPS, over a period of 5–10 years. This allows probing dark photons, dark scalars and pseudo-scalars, and heavy neutral leptons with GeV-scale masses in the direct searches at sensitivities that largely exceed those of existing and projected experiments. The sensitivity to light dark matter through scattering reaches well below the dark matter relic density limits in the range from a few $${\mathrm {\,MeV\!/}c^2}$$ MeV / c 2 up to 100 MeV-scale masses, and it will be possible to study tau neutrino interactions with unprecedented statistics. This paper describes the SHiP experiment baseline setup and the detector systems, together with performance results from prototypes in test beams, as it was prepared for the 2020 Update of the European Strategy for Particle Physics. The expected detector performance from simulation is summarised at the end.

Published
2022
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7. Finite element design of a vibrational membrane to reduce distortion in a bone‐conduction implant transducer

Author

D. H. Shin, K. W. Seong, M. N. Kim, and K. Y. Lee

Subjects
Electrical engineering. Electronics. Nuclear engineering, TK1-9971
Abstract

Abstract This paper describes the finite element design of a vibrational membrane with a cantilever structure to reduce distortion in bone conduction implant (BCI) transducers. To derive the optimal number of cantilevers, a model of ideally aligned components was established based on the structure of a previously proposed transducer, and mechanical vibration analysis was performed using different numbers of cantilevers (two to five). Under the same conditions, similar analyses were performed using vibrational membranes misaligned with the transducer magnet by 0.1 and 0.2 mm. Then, the standard deviations were calculated from the analysis results to numerically compare the magnitudes of vibrations between cantilevers for each cantilever shape. The larger the number of cantilevers, the smaller the standard deviation in both the alignment and misalignment cases. Moreover, from the analysis result, it was confirmed that using a vibrational membrane composed of five cantilevers can reduce distortion in BCI transducers.

Published
2022
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8. Sensitivity of the SHiP experiment to dark photons decaying to a pair of charged particles

Author

SHiP Collaboration, C. Ahdida, A. Akmete, R. Albanese, A. Alexandrov, A. Anokhina, S. Aoki, G. Arduini, E. Atkin, N. Azorskiy, J. J. Back, A. Bagulya, F. Baaltasar Dos Santos, A. Baranov, F. Bardou, G. J. Barker, M. Battistin, J. Bauche, A. Bay, V. Bayliss, G. Bencivenni, A. Y. Berdnikov, Y. A. Berdnikov, M. Bertani, C. Betancourt, I. Bezshyiko, O. Bezshyyko, D. Bick, S. Bieschke, A. Blanco, J. Boehm, M. Bogomilov, I. Boiarska, K. Bondarenko, W. M. Bonivento, J. Borburgh, A. Boyarsky, R. Brenner, D. Breton, V. Büscher, A. Buonaura, S. Buontempo, S. Cadeddu, A. Calcaterra, M. Calviani, M. Campanelli, M. Casolino, N. Charitonidis, P. Chau, J. Chauveau, A. Chepurnov, M. Chernyavskiy, K.-Y. Choi, A. Chumakov, P. Ciambrone, V. Cicero, L. Congedo, K. Cornelis, M. Cristinziani, A. Crupano, G. M. Dallavalle, A. Datwyler, N. D’Ambrosio, G. D’Appollonio, R. de Asmundis, J. De Carvalho Saraiva, G. De Lellis, M. de Magistris, A. De Roeck, M. De Serio, D. De Simone, L. Dedenko, P. Dergachev, A. Di Crescenzo, L. Di Giulio, N. Di Marco, C. Dib, H. Dijkstra, V. Dmitrenko, L. A. Dougherty, A. Dolmatov, D. Domenici, S. Donskov, V. Drohan, A. Dubreuil, O. Durhan, M. Ehlert, E. Elikkaya, T. Enik, A. Etenko, F. Fabbri, O. Fedin, F. Fedotovs, G. Felici, M. Ferrillo, M. Ferro-Luzzi, K. Filippov, R. A. Fini, P. Fonte, C. Franco, M. Fraser, R. Fresa, R. Froeschl, T. Fukuda, G. Galati, J. Gall, L. Gatignon, G. Gavrilov, V. Gentile, B. Goddard, L. Golinka-Bezshyyko, A. Golovatiuk, V. Golovtsov, D. Golubkov, A. Golutvin, P. Gorbounov, D. Gorbunov, S. Gorbunov, V. Gorkavenko, M. Gorshenkov, V. Grachev, A. L. Grandchamp, E. Graverini, J.-L. Grenard, D. Grenier, V. Grichine, N. Gruzinskii, A. M. Guler, Yu. Guz, G. J. Haefeli, C. Hagner, H. Hakobyan, I. W. Harris, E. van Herwijnen, C. Hessler, A. Hollnagel, B. Hosseini, M. Hushchyn, G. Iaselli, A. Iuliano, R. Jacobsson, D. Joković, M. Jonker, I. Kadenko, V. Kain, B. Kaiser, C. Kamiscioglu, D. Karpenkov, K. Kershaw, M. Khabibullin, E. Khalikov, G. Khaustov, G. Khoriauli, A. Khotyantsev, Y. G. Kim, V. Kim, N. Kitagawa, J.-W. Ko, K. Kodama, A. Kolesnikov, D. I. Kolev, V. Kolosov, M. Komatsu, A. Kono, N. Konovalova, S. Kormannshaus, I. Korol, I. Korol’ko, A. Korzenev, V. Kostyukhin, E. Koukovini Platia, S. Kovalenko, I. Krasilnikova, Y. Kudenko, E. Kurbatov, P. Kurbatov, V. Kurochka, E. Kuznetsova, H. M. Lacker, M. Lamont, G. Lanfranchi, O. Lantwin, A. Lauria, K. S. Lee, K. Y. Lee, N. Leonardo, J.-M. Lévy, V. P. Loschiavo, L. Lopes, E. Lopez Sola, V. Lyubovitskij, J. Maalmi, A.-M. Magnan, V. Maleev, A. Malinin, Y. Manabe, A. K. Managadze, M. Manfredi, S. Marsh, A. M. Marshall, A. Mefodev, P. Mermod, A. Miano, S. Mikado, Yu. Mikhaylov, D. A. Milstead, O. Mineev, A. Montanari, M. C. Montesi, K. Morishima, S. Movchan, Y. Muttoni, N. Naganawa, M. Nakamura, T. Nakano, S. Nasybulin, P. Ninin, A. Nishio, B. Obinyakov, S. Ogawa, N. Okateva, B. Opitz, J. Osborne, M. Ovchynnikov, N. Owtscharenko, P. H. Owen, P. Pacholek, A. Paoloni, B. D. Park, A. Pastore, M. Patel, D. Pereyma, A. Perillo-Marcone, G. L. Petkov, K. Petridis, A. Petrov, D. Podgrudkov, V. Poliakov, N. Polukhina, J. Prieto Prieto, M. Prokudin, A. Prota, A. Quercia, A. Rademakers, A. Rakai, F. Ratnikov, T. Rawlings, F. Redi, S. Ricciardi, M. Rinaldesi, Volodymyr Rodin, Viktor Rodin, P. Robbe, A. B. Rodrigues Cavalcante, T. Roganova, H. Rokujo, G. Rosa, T. Rovelli, O. Ruchayskiy, T. Ruf, V. Samoylenko, V. Samsonov, F. Sanchez Galan, P. Santos Diaz, A. Sanz Ull, A. Saputi, O. Sato, E. S. Savchenko, J. S. Schliwinski, W. Schmidt-Parzefall, N. Serra, S. Sgobba, O. Shadura, A. Shakin, M. Shaposhnikov, P. Shatalov, T. Shchedrina, L. Shchutska, V. Shevchenko, H. Shibuya, S. Shirobokov, A. Shustov, S. B. Silverstein, S. Simone, R. Simoniello, M. Skorokhvatov, S. Smirnov, G. Soares, J. Y. Sohn, A. Sokolenko, E. Solodko, N. Starkov, L. Stoel, M. E. Stramaglia, D. Sukhonos, Y. Suzuki, S. Takahashi, J. L. Tastet, P. Teterin, S. Than Naing, I. Timiryasov, V. Tioukov, D. Tommasini, M. Torii, N. Tosi, D. Treille, R. Tsenov, S. Ulin, E. Ursov, A. Ustyuzhanin, Z. Uteshev, L. Uvarov, G. Vankova-Kirilova, F. Vannucci, V. Venturi, I. Vidulin, S. Vilchinski, Heinz Vincke, Helmut Vincke, C. Visone, K. Vlasik, A. Volkov, R. Voronkov, S. van Waasen, R. Wanke, P. Wertelaers, O. Williams, J.-K. Woo, M. Wurm, S. Xella, D. Yilmaz, A. U. Yilmazer, C. S. Yoon, Yu. Zaytsev, A. Zelenov, and J. Zimmerman

Subjects
Astrophysics, QB460-466, Nuclear and particle physics. Atomic energy. Radioactivity, QC770-798
Abstract

Abstract Dark photons are hypothetical massive vector particles that could mix with ordinary photons. The simplest theoretical model is fully characterised by only two parameters: the mass of the dark photon m $$_{\gamma ^{\mathrm {D}}}$$ γ D and its mixing parameter with the photon, $$\varepsilon $$ ε . The sensitivity of the SHiP detector is reviewed for dark photons in the mass range between 0.002 and 10 GeV. Different production mechanisms are simulated, with the dark photons decaying to pairs of visible fermions, including both leptons and quarks. Exclusion contours are presented and compared with those of past experiments. The SHiP detector is expected to have a unique sensitivity for m $$_{\gamma ^{\mathrm {D}}}$$ γ D ranging between 0.8 and 3.3 $$^{+0.2}_{-0.5}$$ - 0.5 + 0.2 GeV, and $$\varepsilon ^2$$ ε 2 ranging between $$10^{-11}$$ 10 - 11 and $$10^{-17}$$ 10 - 17 .

Published
2021
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9. Expert commentary on the challenges and opportunities for surgical site infection prevention through implementation of evidence-based guidelines in the Asia–Pacific Region

Author

K. Morikane, P. L. Russo, K. Y. Lee, M. Chakravarthy, M. L. Ling, E. Saguil, M. Spencer, W. Danker, A. Seno, and E. Edmiston Charles

Subjects
Surgical site infection, Healthcare-associated infection, Guidelines, Implementation, Asia–Pacific, Infectious and parasitic diseases, RC109-216
Abstract

Abstract Introduction Surgical site infections (SSIs) are a significant source of morbidity and mortality in the Asia–Pacific region (APAC), adversely impacting patient quality of life, fiscal productivity and placing a major economic burden on the country’s healthcare system. This commentary reports the findings of a two-day meeting that was held in Singapore on July 30–31, 2019, where a series of consensus recommendations were developed by an expert panel composed of infection control, surgical and quality experts from APAC nations in an effort to develop an evidence-based pathway to improving surgical patient outcomes in APAC. Methods The expert panel conducted a literature review targeting four sentinel areas within the APAC region: national and societal guidelines, implementation strategies, postoperative surveillance and clinical outcomes. The panel formulated a series of key questions regarding APAC-specific challenges and opportunities for SSI prevention. Results The expert panel identified several challenges for mitigating SSIs in APAC; (a) constraints on human resources, (b) lack of adequate policies and procedures, (c) lack of a strong safety culture, (d) limitation in funding resources, (e) environmental and geographic challenges, (f) cultural diversity, (g) poor patient awareness and (h) limitation in self-responsibility. Corrective strategies for guideline implementation in APAC were proposed that included: (a) institutional ownership of infection prevention strategies, (b) perform baseline assessments, (c) review evidence-based practices within the local context, (d) develop a plan for guideline implementation, (e) assess outcome and stakeholder feedback, and (f) ensure long-term sustainability. Conclusions Reducing the risk of SSIs in APAC region will require: (a) ongoing consultation and collaboration among stakeholders with a high level of clinical staff engagement and (b) a strong institutional and national commitment to alleviate the burden of SSIs by embracing a safety culture and accountability.

Published
2021
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10. Sensitivity of the SHiP experiment to light dark matter

Author

The SHiP collaboration, C. Ahdida, A. Akmete, R. Albanese, A. Alexandrov, A. Anokhina, S. Aoki, G. Arduini, E. Atkin, N. Azorskiy, J. J. Back, A. Bagulya, F. Baaltasar Dos Santos, A. Baranov, F. Bardou, G. J. Barker, M. Battistin, J. Bauche, A. Bay, V. Bayliss, G. Bencivenni, A. Y. Berdnikov, Y. A. Berdnikov, M. Bertani, C. Betancourt, I. Bezshyiko, O. Bezshyyko, D. Bick, S. Bieschke, A. Blanco, J. Boehm, M. Bogomilov, I. Boiarska, K. Bondarenko, W. M. Bonivento, J. Borburgh, A. Boyarsky, R. Brenner, D. Breton, V. Büscher, A. Buonaura, L. Buonocore, S. Buontempo, S. Cadeddu, A. Calcaterra, M. Calviani, M. Campanelli, M. Casolino, N. Charitonidis, P. Chau, J. Chauveau, A. Chepurnov, M. Chernyavskiy, K.-Y. Choi, A. Chumakov, P. Ciambrone, V. Cicero, L. Congedo, K. Cornelis, M. Cristinziani, A. Crupano, G. M. Dallavalle, A. Datwyler, N. D’Ambrosio, G. D’Appollonio, R. de Asmundis, J. De Carvalho Saraiva, G. De Lellis, M. de Magistris, A. De Roeck, M. De Serio, D. De Simone, L. Dedenko, P. Dergachev, A. Di Crescenzo, L. Di Giulio, N. Di Marco, C. Dib, H. Dijkstra, V. Dmitrenko, L. A. Dougherty, A. Dolmatov, D. Domenici, S. Donskov, V. Drohan, A. Dubreuil, O. Durhan, M. Ehlert, E. Elikkaya, T. Enik, A. Etenko, F. Fabbri, O. Fedin, F. Fedotovs, G. Felici, M. Ferrillo, M. Ferro-Luzzi, K. Filippov, R. A. Fini, P. Fonte, C. Franco, M. Fraser, R. Fresa, R. Froeschl, C. Frugiuele, T. Fukuda, G. Galati, J. Gall, L. Gatignon, G. Gavrilov, V. Gentile, B. Goddard, L. Golinka-Bezshyyko, A. Golovatiuk, V. Golovtsov, D. Golubkov, A. Golutvin, P. Gorbounov, D. Gorbunov, S. Gorbunov, V. Gorkavenko, M. Gorshenkov, V. Grachev, A. L. Grandchamp, E. Graverini, J.-L. Grenard, D. Grenier, V. Grichine, N. Gruzinskii, A. M. Guler, Yu. Guz, G. J. Haefeli, C. Hagner, H. Hakobyan, I. W. Harris, E. van Herwijnen, C. Hessler, A. Hollnagel, B. Hosseini, M. Hushchyn, G. Iaselli, A. Iuliano, R. Jacobsson, D. Joković, M. Jonker, I. Kadenko, V. Kain, B. Kaiser, C. Kamiscioglu, D. Karpenkov, K. Kershaw, M. Khabibullin, E. Khalikov, G. Khaustov, G. Khoriauli, A. Khotyantsev, Y. G. Kim, V. Kim, N. Kitagawa, J.-W. Ko, K. Kodama, A. Kolesnikov, D. I. Kolev, V. Kolosov, M. Komatsu, A. Kono, N. Konovalova, S. Kormannshaus, I. Korol, I. Korol’ko, A. Korzenev, V. Kostyukhin, E. Koukovini Platia, S. Kovalenko, I. Krasilnikova, Y. Kudenko, E. Kurbatov, P. Kurbatov, V. Kurochka, E. Kuznetsova, H. M. Lacker, M. Lamont, G. Lanfranchi, O. Lantwin, A. Lauria, K. S. Lee, K. Y. Lee, J.-M. Lévy, V. P. Loschiavo, L. Lopes, E. Lopez Sola, V. Lyubovitskij, J. Maalmi, A. Magnan, V. Maleev, A. Malinin, F. Maltoni, Y. Manabe, A. K. Managadze, M. Manfredi, S. Marsh, A. M. Marshall, O. Mattelaer, A. Mefodev, P. Mermod, A. Miano, S. Mikado, Yu. Mikhaylov, D. A. Milstead, O. Mineev, A. Montanari, M. C. Montesi, K. Morishima, S. Movchan, Y. Muttoni, N. Naganawa, M. Nakamura, T. Nakano, S. Nasybulin, P. Ninin, A. Nishio, A. Novikov, B. Obinyakov, S. Ogawa, N. Okateva, B. Opitz, J. Osborne, M. Ovchynnikov, N. Owtscharenko, P. H. Owen, P. Pacholek, A. Paoloni, B. D. Park, A. Pastore, M. Patel, D. Pereyma, A. Perillo-Marcone, G. L. Petkov, K. Petridis, A. Petrov, D. Podgrudkov, V. Poliakov, N. Polukhina, J. Prieto Prieto, M. Prokudin, A. Prota, A. Quercia, A. Rademakers, A. Rakai, F. Ratnikov, T. Rawlings, F. Redi, S. Ricciardi, M. Rinaldesi, Volodymyr Rodin, Viktor Rodin, P. Robbe, A. B. Rodrigues Cavalcante, T. Roganova, H. Rokujo, G. Rosa, T. Rovelli, O. Ruchayskiy, T. Ruf, V. Samoylenko, V. Samsonov, F. Sanchez Galan, P. Santos Diaz, A. Sanz Ull, A. Saputi, O. Sato, E. S. Savchenko, J. S. Schliwinski, W. Schmidt-Parzefall, N. Serra, S. Sgobba, O. Shadura, A. Shakin, M. Shaposhnikov, P. Shatalov, T. Shchedrina, L. Shchutska, V. Shevchenko, H. Shibuya, S. Shirobokov, A. Shustov, S. B. Silverstein, S. Simone, R. Simoniello, M. Skorokhvatov, S. Smirnov, J. Y. Sohn, A. Sokolenko, E. Solodko, N. Starkov, L. Stoel, M. E. Stramaglia, D. Sukhonos, Y. Suzuki, S. Takahashi, J. L. Tastet, P. Teterin, S. Than Naing, I. Timiryasov, V. Tioukov, D. Tommasini, M. Torii, N. Tosi, F. Tramontano, D. Treille, R. Tsenov, S. Ulin, E. Ursov, A. Ustyuzhanin, Z. Uteshev, L. Uvarov, G. Vankova-Kirilova, F. Vannucci, V. Venturi, S. Vilchinski, Heinz Vincke, Helmut Vincke, C. Visone, K. Vlasik, A. Volkov, R. Voronkov, S. van Waasen, R. Wanke, P. Wertelaers, O. Williams, J.-K. Woo, M. Wurm, S. Xella, D. Yilmaz, A. U. Yilmazer, C. S. Yoon, Yu. Zaytsev, A. Zelenov, and J. Zimmerman

Subjects
Beyond Standard Model, Dark matter, Fixed target experiments, Nuclear and particle physics. Atomic energy. Radioactivity, QC770-798
Abstract

Abstract Dark matter is a well-established theoretical addition to the Standard Model supported by many observations in modern astrophysics and cosmology. In this context, the existence of weakly interacting massive particles represents an appealing solution to the observed thermal relic in the Universe. Indeed, a large experimental campaign is ongoing for the detection of such particles in the sub-GeV mass range. Adopting the benchmark scenario for light dark matter particles produced in the decay of a dark photon, with α D = 0.1 and m A′ = 3m χ , we study the potential of the SHiP experiment to detect such elusive particles through its Scattering and Neutrino detector (SND). In its 5-years run, corresponding to 2 · 1020 protons on target from the CERN SPS, we find that SHiP will improve the current limits in the mass range for the dark matter from about 1 MeV to 300 MeV. In particular, we show that SHiP will probe the thermal target for Majorana candidates in most of this mass window and even reach the Pseudo-Dirac thermal relic.

Published
2021
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11. Measurement of the muon flux from 400 GeV/c protons interacting in a thick molybdenum/tungsten target

Author

C. Ahdida, A. Akmete, R. Albanese, A. Alexandrov, A. Anokhina, S. Aoki, G. Arduini, E. Atkin, N. Azorskiy, J. J. Back, A. Bagulya, F. Baaltasar Dos Santos, A. Baranov, F. Bardou, G. J. Barker, M. Battistin, J. Bauche, A. Bay, V. Bayliss, G. Bencivenni, A. Y. Berdnikov, Y. A. Berdnikov, M. Bertani, C. Betancourt, I. Bezshyiko, O. Bezshyyko, D. Bick, S. Bieschke, A. Blanco, J. Boehm, M. Bogomilov, I. Boiarska, K. Bondarenko, W. M. Bonivento, J. Borburgh, A. Boyarsky, R. Brenner, D. Breton, V. Büscher, A. Buonaura, S. Buontempo, S. Cadeddu, A. Calcaterra, M. Calviani, M. Campanelli, M. Casolino, N. Charitonidis, P. Chau, J. Chauveau, A. Chepurnov, M. Chernyavskiy, K.-Y. Choi, A. Chumakov, P. Ciambrone, V. Cicero, L. Congedo, K. Cornelis, M. Cristinziani, A. Crupano, G. M. Dallavalle, A. Datwyler, N. D’Ambrosio, G. D’Appollonio, R. de Asmundis, J. De Carvalho Saraiva, G. De Lellis, M. de Magistris, A. De Roeck, M. De Serio, D. De Simone, L. Dedenko, P. Dergachev, A. Di Crescenzo, L. Di Giulio, N. Di Marco, C. Dib, H. Dijkstra, V. Dmitrenko, S. Dmitrievskiy, L. A. Dougherty, A. Dolmatov, D. Domenici, S. Donskov, V. Drohan, A. Dubreuil, O. Durhan, M. Ehlert, E. Elikkaya, T. Enik, A. Etenko, F. Fabbri, O. Fedin, F. Fedotovs, G. Felici, M. Ferrillo, M. Ferro-Luzzi, K. Filippov, R. A. Fini, P. Fonte, C. Franco, M. Fraser, R. Fresa, R. Froeschl, T. Fukuda, G. Galati, J. Gall, L. Gatignon, G. Gavrilov, V. Gentile, B. Goddard, L. Golinka-Bezshyyko, A. Golovatiuk, D. Golubkov, A. Golutvin, P. Gorbounov, D. Gorbunov, S. Gorbunov, V. Gorkavenko, M. Gorshenkov, V. Grachev, A. L. Grandchamp, E. Graverini, J.-L. Grenard, D. Grenier, V. Grichine, N. Gruzinskii, A. M. Guler, Yu. Guz, G. J. Haefeli, C. Hagner, H. Hakobyan, I. W. Harris, E. van Herwijnen, C. Hessler, A. Hollnagel, B. Hosseini, M. Hushchyn, G. Iaselli, A. Iuliano, R. Jacobsson, D. Joković, M. Jonker, I. Kadenko, V. Kain, B. Kaiser, C. Kamiscioglu, D. Karpenkov, K. Kershaw, M. Khabibullin, E. Khalikov, G. Khaustov, G. Khoriauli, A. Khotyantsev, Y. G. Kim, V. Kim, N. Kitagawa, J.-W. Ko, K. Kodama, A. Kolesnikov, D. I. Kolev, V. Kolosov, M. Komatsu, A. Kono, N. Konovalova, S. Kormannshaus, I. Korol, I. Korol’ko, A. Korzenev, V. Kostyukhin, E. Koukovini Platia, S. Kovalenko, I. Krasilnikova, Y. Kudenko, E. Kurbatov, P. Kurbatov, V. Kurochka, E. Kuznetsova, H. M. Lacker, M. Lamont, G. Lanfranchi, O. Lantwin, A. Lauria, K. S. Lee, K. Y. Lee, J.-M. Lévy, V. P. Loschiavo, L. Lopes, E. Lopez Sola, V. Lyubovitskij, J. Maalmi, A. Magnan, V. Maleev, A. Malinin, Y. Manabe, A. K. Managadze, M. Manfredi, S. Marsh, A. M. Marshall, A. Mefodev, P. Mermod, A. Miano, S. Mikado, Yu. Mikhaylov, D. A. Milstead, O. Mineev, A. Montanari, M. C. Montesi, K. Morishima, S. Movchan, Y. Muttoni, N. Naganawa, M. Nakamura, T. Nakano, S. Nasybulin, P. Ninin, A. Nishio, A. Novikov, B. Obinyakov, S. Ogawa, N. Okateva, B. Opitz, J. Osborne, M. Ovchynnikov, N. Owtscharenko, P. H. Owen, P. Pacholek, A. Paoloni, B. D. Park, A. Pastore, M. Patel, D. Pereyma, A. Perillo-Marcone, G. L. Petkov, K. Petridis, A. Petrov, D. Podgrudkov, V. Poliakov, N. Polukhina, J. Prieto Prieto, M. Prokudin, A. Prota, A. Quercia, A. Rademakers, A. Rakai, F. Ratnikov, T. Rawlings, F. Redi, S. Ricciardi, M. Rinaldesi, Volodymyr Rodin, Viktor Rodin, P. Robbe, A. B. Rodrigues Cavalcante, T. Roganova, H. Rokujo, G. Rosa, T. Rovelli, O. Ruchayskiy, T. Ruf, V. Samoylenko, V. Samsonov, F. Sanchez Galan, P. Santos Diaz, A. Sanz Ull, A. Saputi, O. Sato, E. S. Savchenko, J. S. Schliwinski, W. Schmidt-Parzefall, N. Serra, S. Sgobba, O. Shadura, A. Shakin, M. Shaposhnikov, P. Shatalov, T. Shchedrina, L. Shchutska, V. Shevchenko, H. Shibuya, L. Shihora, S. Shirobokov, A. Shustov, S. B. Silverstein, S. Simone, R. Simoniello, M. Skorokhvatov, S. Smirnov, J. Y. Sohn, A. Sokolenko, E. Solodko, N. Starkov, L. Stoel, M. E. Stramaglia, D. Sukhonos, Y. Suzuki, S. Takahashi, J. L. Tastet, P. Teterin, S. Than Naing, I. Timiryasov, V. Tioukov, D. Tommasini, M. Torii, N. Tosi, D. Treille, R. Tsenov, S. Ulin, E. Ursov, A. Ustyuzhanin, Z. Uteshev, G. Vankova-Kirilova, F. Vannucci, V. Venturi, S. Vilchinski, Heinz Vincke, Helmut Vincke, C. Visone, K. Vlasik, A. Volkov, R. Voronkov, S. van Waasen, R. Wanke, P. Wertelaers, O. Williams, J.-K. Woo, M. Wurm, S. Xella, D. Yilmaz, A. U. Yilmazer, C. S. Yoon, Yu. Zaytsev, and J. Zimmerman

Subjects
Astrophysics, QB460-466, Nuclear and particle physics. Atomic energy. Radioactivity, QC770-798
Abstract

Abstract The SHiP experiment is proposed to search for very weakly interacting particles beyond the Standard Model which are produced in a 400 GeV/c proton beam dump at the CERN SPS. About $$10^{11}$$ 1011 muons per spill will be produced in the dump. To design the experiment such that the muon-induced background is minimized, a precise knowledge of the muon spectrum is required. To validate the muon flux generated by our Pythia and GEANT4 based Monte Carlo simulation (FairShip), we have measured the muon flux emanating from a SHiP-like target at the SPS. This target, consisting of 13 interaction lengths of slabs of molybdenum and tungsten, followed by a 2.4 m iron hadron absorber was placed in the H4 400 GeV/c proton beam line. To identify muons and to measure the momentum spectrum, a spectrometer instrumented with drift tubes and a muon tagger were used. During a 3-week period a dataset for analysis corresponding to $$(3.27\pm 0.07)~\times ~10^{11}$$ (3.27±0.07)×1011 protons on target was recorded. This amounts to approximatively 1% of a SHiP spill.

Published
2020
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12. Sensitivity of the SHiP experiment to Heavy Neutral Leptons

Author

The SHiP collaboration, C. Ahdida, R. Albanese, A. Alexandrov, A. Anokhina, S. Aoki, G. Arduini, E. Atkin, N. Azorskiy, F. Baaltasar Dos Santos, J. J. Back, A. Bagulya, A. Baranov, F. Bardou, G. J. Barker, M. Battistin, J. Bauche, A. Bay, V. Bayliss, G. Bencivenni, Y. A. Berdnikov, A. Y. Berdnikov, I. Berezkina, M. Bertani, C. Betancourt, I. Bezshyiko, O. Bezshyyko, D. Bick, S. Bieschke, A. Blanco, J. Boehm, M. Bogomilov, K. Bondarenko, W. M. Bonivento, J. Borburgh, A. Boyarsky, R. Brenner, D. Breton, R. Brundler, M. Bruschi, V. Büscher, A. Buonaura, S. Buontempo, S. Cadeddu, A. Calcaterra, M. Calviani, M. Campanelli, M. Casolino, N. Charitonidis, P. Chau, J. Chauveau, A. Chepurnov, M. Chernyavskiy, K.-Y. Choi, A. Chumakov, P. Ciambrone, K. Cornelis, M. Cristinziani, A. Crupano, G. M. Dallavalle, A. Datwyler, N. D’Ambrosio, G. D’Appollonio, L. Dedenko, P. Dergachev, J. De Carvalho Saraiva, G. De Lellis, M. de Magistris, A. De Roeck, M. De Serio, D. De Simone, C. Dib, H. Dijkstra, P. Dipinto, A. Di Crescenzo, N. Di Marco, V. Dmitrenko, S. Dmitrievskiy, A. Dolmatov, D. Domenici, S. Donskov, L. A. Dougherty, V. Drohan, A. Dubreuil, J. Ebert, T. Enik, A. Etenko, F. Fabbri, L. Fabbri, A. Fabich, O. Fedin, F. Fedotovs, M. Ferro-Luzzi, G. Felici, K. Filippov, R. A. Fini, P. Fonte, C. Franco, M. Fraser, R. Fresa, R. Froeschl, T. Fukuda, G. Galati, J. Gall, L. Gatignon, G. Gavrilov, V. Gentile, B. Goddard, L. Golinka-Bezshyyko, A. Golovatiuk, D. Golubkov, A. Golutvin, P. Gorbounov, S. Gorbunov, D. Gorbunov, V. Gorkavenko, Y. Gornushkin, M. Gorshenkov, V. Grachev, A. L. Grandchamp, G. Granich, E. Graverini, J.-L. Grenard, D. Grenier, V. Grichine, N. Gruzinskii, Yu. Guz, G. J. Haefeli, C. Hagner, H. Hakobyan, I. W. Harris, C. Hessler, A. Hollnagel, B. Hosseini, M. Hushchyn, G. Iaselli, A. Iuliano, V. Ivantchenko, R. Jacobsson, D. Joković, M. Jonker, I. Kadenko, V. Kain, C. Kamiscioglu, K. Kershaw, M. Khabibullin, E. Khalikov, G. Khaustov, G. Khoriauli, A. Khotyantsev, Y. G. Kim, V. Kim, S. H. Kim, N. Kitagawa, J.-W. Ko, K. Kodama, A. Kolesnikov, D. I. Kolev, V. Kolosov, M. Komatsu, N. Kondrateva, A. Kono, N. Konovalova, S. Kormannshaus, I. Korol, I. Korol’ko, A. Korzenev, V. Kostyukhin, E. Koukovini Platia, S. Kovalenko, I. Krasilnikova, Y. Kudenko, E. Kurbatov, P. Kurbatov, V. Kurochka, E. Kuznetsova, H. M. Lacker, M. Lamont, G. Lanfranchi, O. Lantwin, A. Lauria, K. S. Lee, K. Y. Lee, J.-M. Lévy, L. Lopes, E. Lopez Sola, V. P. Loschiavo, V. Lyubovitskij, A. M. Guler, J. Maalmi, A. Magnan, V. Maleev, A. Malinin, Y. Manabe, A. K. Managadze, M. Manfredi, S. Marsh, A. M. Marshall, A. Mefodev, P. Mermod, A. Miano, S. Mikado, Yu. Mikhaylov, D. A. Milstead, O. Mineev, A. Montanari, M. C. Montesi, K. Morishima, S. Movchan, Y. Muttoni, N. Naganawa, M. Nakamura, T. Nakano, S. Nasybulin, P. Ninin, A. Nishio, A. Novikov, B. Obinyakov, S. Ogawa, N. Okateva, B. Opitz, J. Osborne, M. Ovchynnikov, P. H. Owen, N. Owtscharenko, P. Pacholek, A. Paoloni, R. Paparella, B. D. Park, S. K. Park, A. Pastore, M. Patel, D. Pereyma, A. Perillo-Marcone, G. L. Petkov, K. Petridis, A. Petrov, D. Podgrudkov, V. Poliakov, N. Polukhina, J. Prieto Prieto, M. Prokudin, A. Prota, A. Quercia, A. Rademakers, A. Rakai, F. Ratnikov, T. Rawlings, F. Redi, S. Ricciardi, M. Rinaldesi, P. Robbe, Viktor Rodin, Volodymyr Rodin, A. B. Rodrigues Cavalcante, T. Roganova, H. Rokujo, G. Rosa, T. Rovelli, O. Ruchayskiy, T. Ruf, V. Samoylenko, V. Samsonov, F. Sanchez Galan, P. Santos Diaz, A. Sanz Ull, A. Saputi, O. Sato, E. S. Savchenko, W. Schmidt-Parzefall, N. Serra, S. Sgobba, O. Shadura, A. Shakin, M. Shaposhnikov, P. Shatalov, T. Shchedrina, L. Shchutska, V. Shevchenko, H. Shibuya, S. Shirobokov, A. Shustov, S. B. Silverstein, S. Simone, R. Simoniello, M. Skorokhvatov, S. Smirnov, J. Y. Sohn, A. Sokolenko, E. Solodko, N. Starkov, L. Stoel, B. Storaci, M. E. Stramaglia, D. Sukhonos, Y. Suzuki, S. Takahashi, J. L. Tastet, P. Teterin, S. Than Naing, I. Timiryasov, V. Tioukov, D. Tommasini, M. Torii, N. Tosi, D. Treille, R. Tsenov, S. Ulin, A. Ustyuzhanin, Z. Uteshev, G. Vankova-Kirilova, F. Vannucci, E. van Herwijnen, S. van Waasen, P. Venkova, V. Venturi, S. Vilchinski, M. Villa, Heinz Vincke, Helmut Vincke, C. Visone, K. Vlasik, A. Volkov, R. Voronkov, R. Wanke, P. Wertelaers, J.-K. Woo, M. Wurm, S. Xella, D. Yilmaz, A. U. Yilmazer, C. S. Yoon, P. Zarubin, I. Zarubina, and Yu. Zaytsev

Subjects
Beyond Standard Model, Fixed target experiments, Nuclear and particle physics. Atomic energy. Radioactivity, QC770-798
Abstract

Abstract Heavy Neutral Leptons (HNLs) are hypothetical particles predicted by many extensions of the Standard Model. These particles can, among other things, explain the origin of neutrino masses, generate the observed matter-antimatter asymmetry in the Universe and provide a dark matter candidate. The SHiP experiment will be able to search for HNLs produced in decays of heavy mesons and travelling distances ranging between O $$ \mathcal{O} $$ (50 m) and tens of kilometers before decaying. We present the sensitivity of the SHiP experiment to a number of HNL’s benchmark models and provide a way to calculate the SHiP’s sensitivity to HNLs for arbitrary patterns of flavour mixings. The corresponding tools and data files are also made publicly available.

Published
2019
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13. Discovery potential for directional Dark Matter detection with nuclear emulsions

Author

N. Agafonova, A. Aleksandrov, A. Anokhina, T. Asada, V. V. Ashikhmin, I. Bodnarchuk, A. Buonaura, M. Chernyavskii, A. Chukanov, N. D’Ambrosio, G. De Lellis, A. Di Crescenzo, N. Di Marco, S. Dmitrievski, R. I. Enikeev, R. A. Fini, G. Galati, V. Gentile, S. Gorbunov, Y. Gornushkin, A. M. Guler, H. Ichiki, T. Katsuragawa, N. Konovalova, K. Kuge, A. Lauria, K. Y. Lee, L. Lista, A. S. Malgin, A. Managadze, P. Monacelli, M. C. Montesi, T. Naka, N. Okateva, B. D. Park, D. Podgrudkov, N. Polukhina, F. Pupilli, T. Roganova, A. Rogozhnikov, G. Rosa, O. G. Ryazhskaya, O. Sato, I. R. Shakiryanova, T. Shchedrina, C. Sirignano, J. Y. Sohn, A. Sotnikov, N. Starkov, P. Strolin, V. Tioukov, A. Umemoto, A. Ustyuzhanin, C. S. Yoon, M. Yoshimoto, and S. Vasina

Subjects
Astrophysics, QB460-466, Nuclear and particle physics. Atomic energy. Radioactivity, QC770-798
Abstract

Abstract Direct Dark Matter searches are nowadays one of the most fervid research topics with many experimental efforts devoted to the search for nuclear recoils induced by the scattering of Weakly Interactive Massive Particles (WIMPs). Detectors able to reconstruct the direction of the nucleus recoiling against the scattering WIMP are opening a new frontier to possibly extend Dark Matter searches beyond the neutrino background. Exploiting directionality would also prove the galactic origin of Dark Matter with an unambiguous signal-to-background separation. Indeed, the angular distribution of recoiled nuclei is centered around the direction of the Cygnus constellation, while the background distribution is expected to be isotropic. Current directional experiments are based on gas TPC whose sensitivity is limited by the small achievable detector mass. In this paper we present the discovery potential of a directional experiment based on the use of a solid target made of newly developed nuclear emulsions and of optical read-out systems reaching unprecedented nanometric resolution.

Published
2018
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14. Blended Learning in Biochemistry: The Development of Pre-Class and Post-Class Learning Aids for Electron Transport Chain and Oxidative Phosphorylation

Author

Rebecca K. Y. Lee, Bernard Y. N. Ng, and Daisy M. H. Chen

Abstract

Electron transport chain and oxidative phosphorylation are always a challenging topic for students studying metabolism. We had adopted blended learning in metabolism teaching and evaluated the learning experiences of students. In this project, a pre-class learning aid the "Story Mode" and a post-class learning aid the "Revision Mode" in the "Powerland" was developed that facilitated students learning electron transport chain and oxidative phosphorylation. In the "Story Mode," pathways were presented by short animations and simplified diagram that allowed students to understand basic concepts and recall simple facts of the topic. Students were asked to watch the animations before class to acquire lower level of cognitive learning first, and this facilitated students in understanding more complicated concepts later on during class. Another challenge that students faced was that they were especially weak at integrating metabolic pathways and understand the relationships between these pathways. A metro map was designed in the "Revision Mode" that aided students in knowledge integration, and the functions of biomolecules were summarized in flashcards that helped students in revising the concepts. This interactive self-learning tool was packaged as a courseware using the Articulate Storyline.

Published
2024
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15. Modelling and Measuring Dielectric Constants for Very Thin Materials Using a Coaxial Probe

Author

K. Y. You, Z. Abbas, C.Y. Lee, M. F. A. Malek, K. Y. Lee, and E. M. Cheng

Subjects
Relative effective permittivity, one-port calibration, measured reflection coefficient, open-ended coaxial probe, thin dielectric substrate, Electrical engineering. Electronics. Nuclear engineering, TK1-9971
Abstract

This paper is focused on the non-destructive measurement of the dielectric constants (relative permittivities) of thin dielectric material (0.1 mm – 0.5 mm) using an open-ended coaxial probe with an outer diameter of 4.1 mm. Normalized de-embedding and network error calibration procedures were applied to the coaxial probe. The measured reflection coefficients for the thin samples were taken with a vector network analyzer up to 7 GHz, and the calibrated reflection coefficients were converted to relative dielectric constant using an empirical reflection-coefficient model. The empirical model was created using the regression method and expressed as a polynomial model, and the coefficients of model were obtained by fitting with the data using the Finite Element Method (FEM).

Published
2014

16. Protected Organic Acid Blends as an Alternative to Antibiotics in Finishing Pigs

Author

S. D. Upadhaya, K. Y. Lee, and I. H. Kim

Subjects
Digestibility, Finishing Pigs, Growth Performance, Micro Flora, Protected Organic Acids, Animal culture, SF1-1100, Animal biochemistry, QP501-801
Abstract

A total of 120 finishing pigs ([Yorkshire×Landrace]×Duroc) with an average body weight (BW) of 49.72 ±1.72 kg were used in 12-wk trial to evaluate the effects of protected organic acids on growth performance, nutrient digestibility, fecal micro flora, meat quality and fecal gas emission. Pigs were randomly allotted to one of three dietary treatments (10 replication pens with 4 pigs per pen) in a randomly complete block design based on their initial BW. Each dietary treatment consisted of: Control (CON/basal diet), OA1 (basal diet+0.1% organic acids) and OA2 (basal diet+0.2% organic acids). Dietary treatment with protected organic acid blends linearly improved (p

Published
2014
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17. Effect of Indigenous Herbs on Growth, Blood Metabolites and Carcass Characteristics in the Late Fattening Period of Hanwoo Steers

Author

D. H. Kim, K. H. Kim, I. S. Nam, S. S. Lee, C. W. Choi, W. Y. Kim, E. G. Kwon, K. Y. Lee, M. J. Lee, and Y. K. Oh

Subjects
Herb, Carcass Characteristic, Blood Metabolite, Hanwoo Steer, Animal culture, SF1-1100, Animal biochemistry, QP501-801
Abstract

This study was conducted to evaluate the effects of indigenous herbal supplements on growth, blood metabolites and carcass characteristics in the late fattening period of Hanwoo steers. In a 6 month feeding trial, thirty Hanwoo steers (647±32 kg) were allotted to one of 5 treatment groups, control (basal diet contained lasalocid), licorice, clove, turmeric and silymarin, with six steers per pen. All groups received ad libitum concentrate and 1 kg rice straw/animal/d throughout the feeding trial. Blood samples were collected at the beginning, middle, and the end of the experiment and the steers were slaughtered at the end. Blood glucose, triglyceride, total protein, and albumin concentrations were higher in the turmeric treatment compared with other treatments. Blood urea nitrogen and creatinine concentrations were highest (p

Published
2013
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18. Spectral optical properties of long-range transport Asian dust and pollution aerosols over Northeast Asia in 2007 and 2008

Author

J. Jung, Y. J. Kim, K. Y. Lee, M. G. -Cayetano, T. Batmunkh, J.-H. Koo, and J. Kim

Subjects
Physics, QC1-999, Chemistry, QD1-999
Abstract

As a part of the IGAC (International Global Atmospheric Chemistry) Mega-cities program, aerosol physical and optical properties were continuously measured from March 2007 to March 2008 at an urban site (37.57° N, 126.94° E) in Seoul, Korea. Spectral optical properties of long-range transported Asian dust and pollution aerosols have been investigated based on the year long measurement data. Optically measured black carbon/thermally measured elemental carbon (BC/EC) ratio showed clear monthly variation with high values in summer and low values in winter mainly due to the enhancement of light attenuation by the internal mixing of EC. Novel approach has been suggested to retrieve the spectral light absorption coefficient (babs) from Aethalometer raw data by using BC/EC ratio. Mass absorption efficiency, σabs (=babs/EC) at 550 nm was determined to be 9.0±1.3, 8.9±1.5, 9.5±2.0, and 10.3±1.7 m2 g−1 in spring, summer, fall, and winter, respectively with an annual mean of 9.4±1.8 m2 g−1. Threshold values to classify severe haze events were suggested in this study. Increasing trend of aerosol single scattering albedo (SSA) with wavelength was observed during Asian dust events while little spectral dependence of SSA was observed during long-range transport pollution (LTP) events. Satellite aerosol optical thickness (AOT) and Hysplit air mass backward trajectory analyses as well as chemical analysis were performed to characterize the dependence of spectral optical properties on aerosol type. Results from this study can provide useful information for studies on regional air quality and aerosol's effects on climate change.

Published
2010
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19. Ozone Measurements in the Stratosphere from KSR420S-1 and -2

Author

K. Y. Lee, D. H. Lee, J. Kim, C. J. Park, and H. K. Cho

Subjects
Astronomy, QB1-991
Abstract

The Korean sounding rockets(KSR420S-1, -2) equipped with ozone detectors have been launched at An-heung, Chungchungnam-do, on June 4 and September 1, 1993, respectively. The ozone detector is used to measure the attenuation of solar UV radiation for various frequency bands in the stratosphere, to obtain vertical profiles of the ozone number density in the stratosphere. They confirm that the maximum ozone densities occur near 25km, which is quite consistent with the mean value in the mid-latitude region. Our results from KSR420S-1 and -2 are compared with the other observational data from the Dobson spectrophotometer at Yonsei Univ., the LIDAR at Kyunghee Univ., the SBUV from Nimbus satellite, and the TOVS from NOAA satellite, which were performed simultaneously with the sounding rocket experiment.

Published
1994

21. Non-volatile marine and non-refractory continental sources of particle-phase amine during the North Atlantic Aerosols and Marine Ecosystems Study (NAAMES)

Author

Veronica Z. Berta, Lynn M. Russell, Derek J. Price, Chia-Li Chen, Alex K. Y. Lee, Patricia K. Quinn, Timothy S. Bates, Thomas G. Bell, and Michael J. Behrenfeld

Subjects
Atmospheric Science
Abstract

Amines were measured by aerosol mass spectrometry (AMS) and Fourier transform infrared (FTIR) spectroscopy during the North Atlantic Aerosols and Marine Ecosystems Study (NAAMES) cruises. Both AMS non-refractory (NR) amine ion fragments comprising the AMS CxHyNz family and FTIR non-volatile (NV) primary (C–NH2) amine groups typically had greater concentrations in continental air masses than in marine air masses. Secondary continental sources of AMS NR amine fragments were identified by consistent correlations with AMS NR nitrate, AMS NR f44 (the contribution of AMS ion signal at m/z 44 (CO2+) to the total AMS NR organic mass (OM) signal), ion chromatography (IC) non-sea-salt potassium (nssK+), and radon for most air masses. FTIR NV amine group mass concentrations for particles with diameters µm showed large contributions from a primary marine source that was identified by significant correlations with measurements of wind speed, chlorophyll a (chl a), seawater dimethylsulfide (DMS), AMS NR chloride, and IC sea salt as well as FTIR NV alcohol groups in both marine and continental air masses. FTIR NV amine group mass concentrations in and µm particle samples in marine air masses likely have a biogenic secondary source associated with strong correlations with FTIR NV acid groups, which are not present for µm particle samples. The average seasonal contribution of AMS NR amine fragments and FTIR NV amine groups ranged from 27±57 % amine from primary marine sources and 73±152 % secondary continental amine during early spring to 53±76 % amine from primary marine sources and 47±68 % secondary continental amine during winter. These results demonstrate that AMS NR and FTIR NV amine measurements are complementary and can be used together to investigate the variety and sources of amines in the marine environment.

Published
2023

26. How to set up regional STEMI networks: a 'Stent - Save a life!' initiative

Author

Awad Mohamed, Gabor G. Toth, William Wijns, Hélder Pereira, Michael K Y Lee, Alfonsina Candiello, Rhena Delport, Adriaan Snyders, Jorge A. Belardi, Andreas Baumbach, Jan J. Piek, Jorge Mayol, Paul Jau Lueng Ong, Thomas Alexander, and Christoph Naber

Subjects
business.industry, medicine.medical_treatment, MEDLINE, medicine.disease, Organizational power, surgical procedures, operative, Daily practice, Angioplasty, medicine, National level, cardiovascular diseases, Myocardial infarction, Medical emergency, Cardiology and Cardiovascular Medicine, Set (psychology), business
Abstract

Clinical guidelines recommend the development of ST-elevation myocardial infarction (STEMI) networks at community, regional and/or national level to offer ideally primary coronary angioplasty, or, at least the best available STEMI care to all patients. However, there is a discrepancy between this clinical recommendation and daily practice, with no coordinated care for STEMI patients in many regions of the world. While this can be a consequence of lacking resources, in reality, it is more frequently a lack of organizational power. In this paper, the Stent-Save a life! Initiative proposes a practical methodology to effectively set up a STEMI network in any region of the world, with existing resources, and to continuously develop the STEMI network once established.

Published
2022

27. The radiobiological effect of using Acuros XB vs anisotropic analytical algorithm on hepatocellular carcinoma stereotactic body radiation therapy

Author

Michael L M, Cheung, Monica W K, Kan, Vanessa T Y, Yeung, Darren M C, Poon, Michael K M, Kam, Louis K Y, Lee, and Anthony T C, Chan

Subjects
Carcinoma, Hepatocellular, Oncology, Radiological and Ultrasound Technology, Radiotherapy Planning, Computer-Assisted, Liver Neoplasms, Humans, Radiology, Nuclear Medicine and imaging, Radiosurgery, Algorithms
Abstract

The purpose of this work was to study the radiobiological effect of using Acuros XB (AXB) vs Analytic Anisotropic Algorithm (AAA) on hepatocellular carcinoma (HCC) stereotactic body radiation therapy (SBRT). Seventy SBRT volumetric modulated arc therapy (VMAT) plans for HCC were calculated using AAA and AXB respectively with the same treatment parameters. Published tumor control probability (TCP) and normal tissue complication probability (NTCP) models were used to quantify the effect of dosimetric difference between AAA and AXB on TCP, NTCP and uncomplicated tumor control probability (UTCP). There was an average decrease of 2.5% in 6-month TCP. Normal liver has the largest average decrease in NTCP which was 59.7%. Bowels followed with 26.6% average decrease in NTCP. Duodenum, stomach and esophagus had 10.2%, 5.1%, and 4.3% average decrease in NTCP. There was an average decrease of 1.8% and up to 7.2% in 6-month UTCP. There was an overall decrease in TCP, NTCP, and UTCP for HCC SBRT plans calculated using AXB compared to AAA which could be clinically significant.

Published
2022

28. Evaluating SOA formation from different sources of semi- and intermediate-volatility organic compounds from the Athabasca oil sands

Author

Jacob M. Sommers, Craig A. Stroud, Max G. Adam, Jason O'Brien, Jeffrey R. Brook, Katherine Hayden, Alex K. Y. Lee, Kun Li, John Liggio, Cristian Mihele, Richard L. Mittermeier, Robin G. Stevens, Mengistu Wolde, Andreas Zuend, and Patrick L. Hayes

Subjects
Chemistry (miscellaneous), ddc:333.7, Environmental Chemistry, respiratory system, Pollution, Analytical Chemistry
Abstract

Organic aerosols are a major component of particulate matter but have a complex and uncertain effect on climate and health.

Published
2022

29. Multiple Frequencies Five-Port Reflectometer (FPR) for Pure and Adulterated Honeys

Author

E. M. Cheng, A. B. Shahriman, K. Y. Lee, S. F. Khor, N. F. Mohd Nasir, S. A. Baharuddin, C. W. S. Robiah Mohamad, and E. Z. Mohd Tarmizi

Subjects
Astronomy and Astrophysics, Electrical and Electronic Engineering
Abstract

Honey adulteration is one of the major health concerns among honey consumers, it is essential to inspect the quality of honey. One of the methods is to characterize the honey by using the microwave reflection technique. A Five-Port Reflectometer (FPR) is proposed in this work. The microstrip Five-Port ring junction circuit was designed for multiple frequencies of 0.60 GHz, 2.28 GHz, and 3.47 GHz. The fabricated circuit works with an analogue-digital converter, open-ended coaxial sensor, diode detectors and computer to form a complete FPR measurement system. The reflection measurements were conducted on Honey Gold and Trigona Honey for multiple frequencies. The performance of the FPR in s-parameter measurement was verified by Vector Network Analyzer (VNA). This study shown that the performance of FPR in term of reflection measurement has promising accuracy which is comparable with VNA. The FPR can be used as an alternative instrumentation system for characterizing pure and adulterated honey.

Published
2022

30. Heart failure with improved ejection fraction (HFimpEF) in patients treated with sacubitril/valsartan (SV)

Author

M G Kong, J Suh, I K Moon, K Y Lee, H J Jang, J S Kim, and I J Choi

Subjects
Cardiology and Cardiovascular Medicine
Abstract

Introduction Several studies demonstrated that patients with improvement of left ventricular ejection fraction (LVEF) and symptoms had good prognosis in heart failure with reduced ejection fraction (HFrEF). Based on these results, new classification of HF according to LVEF was currently proposed. Sacubitril/valsartan (SV) is recommended as one of the first-line therapy of HFrEF patients. SV reduced hospitalization for HF and cardiovascular mortality compared to enalapril in PARADIGM-HF trial. However, it is unclear that patients with improvement of LVEF also have better prognosis compared to patients without LVEF improvement among patients treated with SV. Purpose We aimed to evaluate the clinical characteristics and outcomes of heart failure with improved ejection fraction (HFimpEF) in heart failure with reduced ejection fraction (HFrEF) patients treated with SV. Methods We analyzed 230 patients with HFrEF taking SV in a multicenter retrospective cohort (RECORD-SV registry) from 2017 to 2019. Enrolled 230 patients were performed baseline and 1-year follow-up echocardiography. Based on 2 echocardiographic results, we defined “HFimpEF” as HF with a baseline LVEF ≤40%, ≥10% increase from baseline LVEF and a follow-up measurement of LVEF >40%. Others were defined as “Persistent HFrEF”. We analyzed and compared clinical characteristics and outcomes between two groups. Primary endpoint was a composite outcome of all-cause death and hospitalization for HF (HHF). Results From 230 patients, 65 patients with HFimpEF and 165 patients with Persistent HFrEF were analyzed. The median follow-up duration was 557 days (interquartile range 364 to 727 days). Patients with HFimpEF had a higher prevalence of female gender (50.8% vs. 30.3%) and de novo HF (44.6% vs. 21.2%). There were no significant differences for age, etiology (ischemic vs. non-ischemic), diabetes, atrial fibrillation, hypertension, and HF medications including SV dose between two groups. Patients with HFimpEF showed lower rate of all-cause death or HHF as a primary endpoint compared to patients with persistent HFrEF (6.2% vs. 22.4%; IPTW adjusted HR 0.24; 95% CI 0.13–0.46; p Conclusions HFimpEF patients had better clinical outcomes compared to those with persistent HFrEF in HFrEF patients treated with SV. Non-prior MI and de novo HF were independent predictors of HFimpEF in patients treated with SV. Funding Acknowledgement Type of funding sources: None.

Published
2022

31. The effect of the magnetic fields from three different configurations of the MRIgRT systems on the dose deposition from lateral opposing photon beams in a laryngeal geometry – A Monte Carlo study

Author

Kenneth C.W. Wong, Macy Tong, Anthony T.C. Chan, Louis K Y Lee, Vivien W.S. Chu, and Monica W.K. Kan

Subjects
Physics, MR-Linac, Field (physics), Strategy and Management, Mechanical Engineering, Monte Carlo method, Metals and Alloys, R895-920, Geometry, Electron, Edge (geometry), Radiation, Air cavity, MRIgRT, Industrial and Manufacturing Engineering, Imaging phantom, Magnetic field, Transverse plane, Medical physics. Medical radiology. Nuclear medicine, Monte Carlo
Abstract

Objective To investigate the impact of different magnetic field strengths and orientations on the dose deposition from lateral opposing photon beams irradiating a laryngeal geometry, with particular attention focused on the dose homogeneity of the area around the air cavity inside the larynx. Methods Geant4 simulation toolkit was used to perform Monte Carlo simulations on a phantom resembling the larynx. The energy spectrum of a 6 ​MV photon beam from a Varian Clinac iX machine was used to provide the source of radiation. Three configurations of the Magnetic Resonance Image-Guided Radiation Therapy (MRIgRT) system were simulated: the Fixed Cylindrical (FC) geometry, the Longitudinal Rotating Biplanar (LRBP) geometry, and the Transverse Rotating Biplanar (TRBP) geometry. Uniform magnetic fields of different field strengths were applied. The relative dose maps and the homogeneity index (HI) were obtained for evaluations. Results The LRBP geometry together with a magnetic field strength of 0.5 ​T produced the most homogeneous dose distribution with a HI of 0.139 for the region of interest around the air cavity, compared with a HI of 0.180 when the magnetic field was absent. For TRBP geometry, the dose distribution shifted towards the cranial direction, leading to a region of hot spots at the superior edge and a region of cold spots at the inferior edge of the irradiated volume. The HI around the air cavity was therefore worse. In addition, strong electron streaming effect (ESE) was observed. For the FC geometry, hot and cold spots were formed around the air cavity which increased the HI. Conclusions Out of the three configurations of the MRIgRT systems, the LRBP geometry produced the most clinically beneficial dose distribution in which it provided a higher dose to the treatment area and a boost in dose to the tissue immediately adjacent to the air cavity.

Published
2021

32. Effect of Procedural Technique on Cardiovascular Outcomes Following Second-Generation Drug-Eluting Resorbable Magnesium Scaffold Implantation

Author

Michael Joner, Yuichi Ozaki, Michael Haude, Gebremedhin D. Melaku, Hector M. Garcia-Garcia, Ron Waksman, Michael K.-Y. Lee, Stefano Galli, and Stefan Verheye

Subjects
Drug, Target lesion, medicine.medical_specialty, Scaffold, media_common.quotation_subject, Coronary Artery Disease, 030204 cardiovascular system & hematology, Prosthesis Design, Lesion, 03 medical and health sciences, Percutaneous Coronary Intervention, 0302 clinical medicine, Absorbable Implants, medicine, Humans, Magnesium, In patient, 030212 general & internal medicine, Target lesion revascularization, media_common, business.industry, Drug-Eluting Stents, General Medicine, Treatment Outcome, Pharmaceutical Preparations, Diameter stenosis, Radiology, medicine.symptom, Cardiology and Cardiovascular Medicine, business, Cardiovascular outcomes
Abstract

BACKGROUND This study sought to assess target lesion failure (TLF) and clinically driven target lesion revascularization (CD-TLR) through 1 year following second-generation drug-eluting magnesium scaffold (Magmaris) implantation using a dedicated technique (so-called "4 P's" strategy). METHODS AND RESULTS The 4 P's strategy stands for: correct patient selection, proper scaffold sizing, pre-dilatation (

Published
2021

34. Magnetic-field-modulated radiotherapy (MagMRT) in inhomogeneous medium and its potential applications

Author

Vivien W S Chu, Monica W K Kan, Louis K Y Lee, Kenneth C W Wong, and Anthony T C Chan

Subjects
Magnetic Fields, Phantoms, Imaging, Water, Lung, Monte Carlo Method, General Nursing
Abstract

Objective. To study the effects of magnetic field gradients on the dose deposition in an inhomogeneous medium and to present the benefits offered by magnetic-field-modulated radiotherapy (MagMRT) under multiple radiation beams. Approach. Monte Carlo simulations were performed using the Geant4 simulation toolkit with a 7 MV photon beam from an Elekta Unity system. A water cuboid embedded with material slabs of water, bone, lung or air was used to study the effects of MagMRT within inhomogeneous medium. Two cylindrical water phantoms, with and without a toroidal lung insert embedded, were used to study the effects of MagMRT under single, opposing or four cardinal radiation beams. Optimized magnetic field variations in the form of a wavelet were used to induce dose modulation within the material slabs or at the iso-center of the phantoms. Main results. The magnitudes of the dose enhancement and reduction induced by the magnetic field gradients become more prominent in a medium of lower density. A maximum dose increase of 6.5% and a decrease of 4.8% were found inside bone, while an increase of 20.4% and a decrease of 13.9% were found in lung tissue. Under multiple radiation beams, the dose enhancement can be induced at the iso-center while the dose reduction occurs in regions around the tumor. For the case with four cardinal beams irradiating a homogeneous water cylinder, an 8.4% of dose enhancement and a 2.4% of dose reduction were found. When a toroidal lung insert was embedded, a maximum dose enhancement of 9.5% and a reduction of 17.0% were produced for anterior-posterior opposing fields. Significance. With an optimized magnetic field gradient, MagMRT can induce a dose boost to the target while producing a better sparing to the surrounding normal tissue, resulting in a sharper dose fall-off in all directions outside the target volume.

Published
2022

35. Austenite/ferrite interface movement during intercritical annealing of a medium Mn steel

Author

G. D. Wang, K. Y. Lee, M. K. Bai, Yi Hongliang, J. H. Ryu, D. P. Yang, and R.D.K. Misra

Subjects
Austenite, Materials science, Mechanics of Materials, Intercritical annealing, Mechanical Engineering, Ferrite (iron), Interface (computing), Isothermal annealing, Metallurgy, General Materials Science, Dilatometer, Condensed Matter Physics, Local equilibrium
Abstract

The austenite/ferrite interface movement during intercritical annealing of 0.15C–8.0Mn–2.1Al (wt-%) steel was simulated by DICTRA software under local equilibrium and then confirmed experimentally....

Published
2021

37. ODP511 Relationship between TSH and Free Thyroxine in Outpatient Cancer Patient Population

Author

Jieli Li, Hussam Alkhalaileh, Ruhan Wei, Jason K Y Lee, and JoAnna Williams

Subjects
Endocrinology, Diabetes and Metabolism
Abstract

Background The inverse log-linear relationship between TSH and free thyroxine (FT4) is well established and reliably used for evaluation of hypothalamus-pituitary-thyroid axis function. However, there are limited data regarding pathophysiologic states in the TSH-FT4 relationship. The purpose of this study was to evaluate thyroid pituitary hypothalamic feedback regulation by the inverse log TSH and FT4 relationship in cancer patient population at the Ohio State University Comprehensive Cancer Center (OSUCCC-James). Methods This retrospective study analyzed the correlation between TSH and FT4 results from 13039 outpatient subjects collected in August 2019-November 2021 at Department of Family Medicine (OSU Wexner Medical Center), Department of Oncology and Department of Chemotherapy (OSUCCC-James). Time of collection for TSH and FT4 was from 7am to 7pm. Data were analyzed by morning (7am-12pm) and afternoon (12pm-7pm). Spearman correlation and non-linear fit were used for data analysis. Sex differences were analyzed as well in each group. Results No significant differences of TSH or FT4 results were found across all study groups and times in both males and females. Overall, an inverse correlation was observed between TSH and FT4 in the morning and afternoon for both male and female populations in all the three groups. Further analysis by non-linear model in log TSH and FT4 showed a worse fit in the group of Oncology compared to the group of Family Medicine, specifically in the morning data set in both males and females. Interestingly, the inverse non-linear relationship between log TSH and FT4 in the female group designated Chemotherapy showed a better fit in the afternoon, compared with other data sets in the same group. Conclusions In cancer patients, the inverse non-linear relationship between TSH and FT4 is weak, which might be resultant of malignancy or medication treatments, or other unknown reasons. The results advance understanding of the pathophysiology and challenges of laboratory diagnosis of thyroid disease in cancer patients. A better understanding of the complex nature of the TSH-FT4 relationship may need further study with better defining subclinical states of cancer patients. Presentation: No date and time listed

Published
2022

39. Tumor-immune microenvironment lab chip integrating liquid-dielectrophoresis operation

Author

Y.-C. Chen, K.-Y. Lee, W.-L. Sun, W.-C. Huang, Y.-S. Wang, W.-C. Chang, and C.-H. Liu

Subjects
General Engineering, General Physics and Astronomy
Abstract

Immunotherapy drugs have effects on the activity and efficacy of T cells in cancer therapy. However, the selection of personalized medicines in the clinic is difficult. Therefore, how to simplify the process is an important issue. This study presented a three-dimensional culture in a microfluidic device. Cancer cells were cultured in the center with GelMA (Gelatin methacryloyl) to mimic the tumor tissue, while microchannels were used to mimic immune cells in peripheral blood in this chip. The T-cell infiltration into the simulated tumor environment in the chip was observed by an imaging system. In addition, a reduction in the viability of cancer cells following T-cell infiltration was also observed. Moreover, the mortality rate of cancer cells increased after cancer cells were treated with atezolizumab or pembrolizumab. In conclusion, these results demonstrate the potential of our chip for cancer research and clinical drug efficacy.

Published
2023

41. Characterization of submicron organic particles in Beijing during summertime: comparison between SP-AMS and HR-AMS

Author

Weiqi Xu, Jian Zhao, Dantong Liu, Yangzhou Wu, Qi Zhang, Mindong Chen, Alex K. Y. Lee, Daniel J. Jacob, Jianhuai Ye, Yele Sun, Jie Zhang, Conghui Xie, Yiming Qin, Zhao Xiuyong, Scot T. Martin, Junfeng Wang, Fuzhen Shen, Paul E. Ohno, Xinlei Ge, and Pingqing Fu

Subjects
Atmospheric Science, Biomass (ecology), Haze, 010504 meteorology & atmospheric sciences, 010501 environmental sciences, Particulates, 01 natural sciences, lcsh:QC1-999, Aerosol, lcsh:Chemistry, lcsh:QD1-999, Beijing, Environmental chemistry, Environmental science, Biomass burning, Air quality index, lcsh:Physics, 0105 earth and related environmental sciences
Abstract

Black carbon (BC) particles in Beijing summer haze play an important role in the regional radiation balance and related environmental processes. Understanding the factors that lead to variability of the impacts of BC remains limited. Here, we present observations by a soot-particle aerosol mass spectrometer (SP-AMS) of BC-containing submicron particulate matter (BC−PM1) in Beijing, China, during summer 2017. These observations were compared to concurrently measured total non-refractory submicron particulate matter (NR−PM1) by a high-resolution aerosol mass spectrometer (HR-AMS). Distinct properties were observed between NR−PM1 and BC−PM1 relevant to organic aerosol (OA) composition. Hydrocarbon-like OA (HOA) in BC−PM1 was found to be up to 2-fold higher than that in NR−PM1 in fresh vehicle emissions, suggesting that a part of HOA in BC−PM1 may be overestimated, likely due to the change of collection efficiency of SP-AMS. Cooking-related OA was only identified in NR−PM1, whereas aged biomass burning OA (A-BBOA) was a unique factor only identified in BC−PM1. The A-BBOA was linked to heavily coated BC, which may lead to enhancement of the light absorption ability of BC by a factor of 2 via the “lensing effect”. More-oxidized oxygenated OA identified in BC-containing particles was found to be slightly different from that observed by HR-AMS, mainly due to the influence of A-BBOA. Overall, these findings highlight that BC in urban Beijing is partially of agricultural fire origin and that a unique biomass-burning-related OA associated with BC may be ubiquitous in aged BC−PM1, and this OA may play a role in affecting air quality and climate that has not previously been fully considered.

Published
2020

42. Short-term dual antiplatelet therapy in diabetic patients admitted for acute coronary syndrome treated with a new-generation drug-eluting stent

Author

Nousjka P. A. Vranken, Saman Rasoul, Jasper J. P. Luijkx, Tobias F. S. Pustjens, Sonja Postma, Evelien J. Kolkman, Elvin Kedhi, Sodiqur Rifqi, Michael K. Y. Lee, Henning Ebelt, Béla Merkely, Monica Verdoia, Wojtek Wojakowski, Arnoud A. W. J. van ’t Hof, Harry Suryapranata, and Giuseppe De Luca

Subjects
Stroke, Endocrinology, Percutaneous Coronary Intervention, Treatment Outcome, Endocrinology, Diabetes and Metabolism, Dual Anti-Platelet Therapy, Internal Medicine, Diabetes Mellitus, Myocardial Infarction, Humans, Drug-Eluting Stents, Acute Coronary Syndrome, Platelet Aggregation Inhibitors
Abstract

The optimal duration of dual antiplatelet therapy (DAPT) in patients with diabetes mellitus (DM) admitted with acute coronary syndrome (ACS) and treated with a drug-eluting stent (DES) remains unclear. This is a prespecified sub-study from the Randomised Evaluation of short-term DUal antiplatelet therapy in patients with acute Coronary syndromE treated with a new generation DES (REDUCE) trial that was designed to determine the efficacy and safety of short-term versus standard 12 months DAPT in diabetic patients with ACS undergoing percutaneous coronary intervention (PCI) using the COMBO stent.In this study we included ACS diabetic patients enroled in the REDUCE trial treated with the COMBO stent and randomly assigned to either 3 or 12 months of DAPT. The primary study endpoint was the composite of all-cause mortality, myocardial infarction (MI), stent thrombosis (ST), stroke, target vessel revascularisation (TVR), and bleeding complications at 12 and 24 months follow-up.A total of 307 diabetic patients were included, of which 162 (52.8%) in the 3 months DAPT group and 145 (47.2%) in the 12 months DAPT group. Patient characteristics, PCI success, and number of stents used were similar in the 3 and 12 months DAPT groups. Occurrence of the primary study endpoint at 12 and 24 months follow-up was comparable between the two groups (3.1 vs. 3.5%, p = 0.865, and 15.8 vs. 14.9%, p = 0.824, respectively). Moreover, the prevalence of the specific clinical outcome parameters (all-cause mortality), MI, ST, stroke, TVR, and bleeding was similar in both study groups.This sub-analysis shows similar clinical outcomes following 3 months DAPT as compared to 12 months DAPT in diabetic patients undergoing PCI for ACS using the COMBO stent. These results suggest that, even in this particular subset of patients, short duration of DAPT might be considered safe. Future larger studies are warranted to provide more precise estimations in terms of safety and efficacy of short term DAPT in these high-risk patients.

Published
2022

45. The Case for Improved Interprofessional Care: Fatal Analgesic Overdose Secondary to Acute Dental Pain during Pregnancy

Author

Sarah K. Y. Lee, Rocio B. Quinonez, Alice Chuang, Stephanie M. Munz, and Darya Dabiri

Subjects
Dentistry, RK1-715
Abstract

Prenatal oral health extends beyond the oral cavity, impacting the general well-being of the pregnant patient and her fetus. This case report follows a 19-year-old pregnant female presenting with acute liver failure secondary to acetaminophen overdose for management of dental pain following extensive dental procedures. Through the course of her illness, the patient suffered adverse outcomes including fetal demise, acute kidney injury, spontaneous bacterial peritonitis, and septic shock before eventual death from multiple organ failure. In managing the pregnant patient, healthcare providers, including physicians and dentists, must recognize and optimize the interconnected relationships shared by the health disciplines. An interdisciplinary approach of collaborative and coordinated care, the timing, sequence, and treatment for the pregnant patient can be improved and thereby maximize overall quality of health. Continued efforts toward integrating oral health into general healthcare education through interprofessional education and practice are necessary to enhance the quality of care that will benefit all patients.

Published
2016
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46. Effect of Relative Humidity on Secondary Brown Carbon Formation in Aqueous Droplets

Author

Alex K. Y. Lee, Nethmi Yasara Kasthuriarachchi, Yong Jie Li, Laura-Hélèna Rivellini, and Xi Chen

Subjects
Aerosols, Ammonium sulfate, Aqueous solution, Chemistry, Inorganic chemistry, Evaporation, Water, Humidity, Glyoxal, General Chemistry, 010501 environmental sciences, 01 natural sciences, Chemical reaction, Carbon, Aerosol, chemistry.chemical_compound, Ammonium Sulfate, Environmental Chemistry, Aerosol mass spectrometry, Relative humidity, 0105 earth and related environmental sciences
Abstract

Atmospheric brown carbon (BrC) is a significant contributor to particulate light absorption. Reactions between small aldehydes and reduced nitrogen species have been shown to produce secondary BrC in atmospheric droplets. These reactions can be substantially accelerated upon droplet evaporation. Despite aqueous droplets undergoing continuous water evaporation and uptake in response to the surrounding relative humidity (RH), secondary BrC formation in these droplets under various RH conditions remains poorly understood. In this work, we investigate BrC formation from reactions of two aqueous-phase precursors, glyoxal and methylglyoxal, with ammonium sulfate or glycine in aqueous droplets after drying at a range of RH (30-90%). Our results illustrate, for the first time, that BrC production varies as a function of RH. For all four chemical reaction systems being investigated, mass absorption efficiencies (MAE, m2/g C) of aqueous aerosol products (from 270 to 512 nm wavelength range) generally increase with reducing RH to reach a maximum at ∼55-65% RH and subsequently decrease, caused by further drying. Chemical characterization using high-resolution aerosol mass spectrometry shows that the formation of nitrogen-containing organic species also follows a similar variation with RH. Our observations reveal that the acceleration of BrC production from evaporation of water may be diminished by other factors, such as limited particle-phase water content, phase transition, and volatility of reactants and products. Overall, our results highlight that intermediate RH conditions in the atmosphere may be more efficient in secondary BrC formation, indicating that the effect of RH needs to be included in atmospheric models for a more accurate representation of light-absorbing aerosol formation in aqueous droplets.

Published
2020

47. Light Absorbing Properties of Primary and Secondary Brown Carbon in a Tropical Urban Environment

Author

Max G. Adam, Alex K. Y. Lee, Nethmi Yasara Kasthuriarachchi, and Laura-Hélèna Rivellini

Subjects
Aerosols, Air Pollutants, Primary (chemistry), Climate, Coal combustion products, General Chemistry, 010501 environmental sciences, Atmospheric sciences, 01 natural sciences, Carbon, Wavelength, Air Pollution, Dispersion (optics), Environmental Chemistry, Environmental science, Particulate Matter, Climate model, Biomass, Absorption (electromagnetic radiation), Brown carbon, Air quality index, Environmental Monitoring, 0105 earth and related environmental sciences
Abstract

Brown carbon (BrC) has significant climatic impact, but its emission sources and formation processes remain under-represented in climate models. However, there are only limited field studies to quantify the light absorption properties of specific types of primary and secondary organic aerosols (POAs and SOAs) in different environments. This work investigates the light absorption properties of the major OA components in Singapore, a well-developed city in the tropical region, where air quality can be influenced by multiple local urban sources and regional biomass burning events. The source-specific mass absorption cross-section (MAC) and wavelength dependence of different BrC components were quantified based on highly time-resolved aerosol chemical composition and absorption measurements. In particular, the combustion-related emission sources were the primary contributors to BrC light absorption and they were moderately absorbing. The SOA materials, which were freshly formed under atmospheric conditions with industrial influences, were also moderately light absorptive. The aged SOA components that were composed of aged regional emissions, including biomass burning and coal combustion emissions from nearby regions, were weakly light absorbing, highlighting the possibility of photobleaching of BrC during their atmospheric aging and dispersion. Lastly, our estimations illustrate that typical urban POAs and SOAs can contribute up to approximately 36-58% of the BrC absorption, even in some urban locations that are influenced by biomass burning emissions.

Published
2020

48. Relative Humidity History Affects Hygroscopicity of Mixed Particles of Glyoxal and Reduced Nitrogenous Species

Author

Masao Gen, Chak K. Chan, Yong Jie Li, Alex K. Y. Lee, Xi Chen, Nethmi Yasara Kasthuriarachchi, and Yangxi Chu

Subjects
Aerosols, Nitrogen, Humidity, Glyoxal, General Chemistry, 010501 environmental sciences, medicine.disease, 01 natural sciences, chemistry.chemical_compound, chemistry, Environmental chemistry, Water uptake, Wettability, medicine, Environmental Chemistry, Relative humidity, Dehydration, Cycling, 0105 earth and related environmental sciences
Abstract

The relative humidity (RH) history that manifests the cycling of dehydration (water evaporation) and hydration (water uptake) may affect particle-phase reactions, products from which have strong influences on the physical properties and thus climatic effects of atmospheric particles. Using single-trapped particles, we show herein hygroscopic growths of mixed particles with reactive species undergoing three types of RH cycles, simulating different degrees of particle-phase reactions in the atmosphere. The reactive species are the widely known α-dicarbonyl glyoxal (GLY), and five reduced nitrogenous species, ammonium sulfate (AS), glycine (GC), l-alanine (AL), dimethylamine (DMA), and diethylamine (DEA). The results showed that the mixed particles after reactions generally had altered efflorescence relative humidity (ERH) and deliquescence relative humidity (DRH) values and reduced hygroscopic growths at moderately high RH (80%) conditions. For example, with an additional slow drying step, the mean mass growth factors at 90% RH during dehydration dropped from 2.56 to 2.02 for GC/GLY mixed particles and from 2.45 to 1.23 for AL/GLY mixed particles. The reduced hygroscopicity with more RH cycling will thus lead to less efficient light scattering of the mixed particles, thereby resulting in less cooling and exacerbating direct heating due to light absorption by the products formed.

Published
2020

49. Validation of MAX-DOAS retrievals of aerosol extinction, SO2, and NO2 through comparison with lidar, sun photometer, active DOAS, and aircraft measurements in the Athabasca oil sands region

Author

Jason S. Olfert, Ralf M. Staebler, Hans D. Osthoff, Vitali Fioletov, Jeffrey R. Brook, Akshay Lobo, James A. Whiteway, Megan D. Willis, Zoe Y. W. Davis, Ihab Abboud, C. Mihele, Alex K. Y. Lee, Robert McLaren, Monika Aggarwaal, Elijah G. Schnitzler, Kevin Strawbridge, Udo Frieß, Chris A. McLinden, Jason M. O'Brien, and Sabour Baray

Subjects
Pollution, Atmospheric Science, 010504 meteorology & atmospheric sciences, Differential optical absorption spectroscopy, media_common.quotation_subject, 010501 environmental sciences, 01 natural sciences, Trace gas, AERONET, Aerosol, Sun photometer, Boundary layer, Lidar, 13. Climate action, Environmental science, 0105 earth and related environmental sciences, Remote sensing, media_common
Abstract

Vertical profiles of aerosols, NO2, and SO2 were retrieved from Multi-Axis Differential Optical Absorption Spectroscopy (MAX-DOAS) measurements at a field site in northern Alberta, Canada, during August and September 2013. The site is approximately 16 km north of two mining operations that are major sources of industrial pollution in the Athabasca oil sands region. Pollution conditions during the study ranged from atmospheric background conditions to heavily polluted with elevated plumes, according to the meteorology. This study aimed to evaluate the performance of the aerosol and trace gas retrievals through comparison with data from a suite of other instruments. Comparisons of aerosol optical depths (AODs) from MAX-DOAS aerosol retrievals, lidar vertical profiles of aerosol extinction, and the AERONET sun photometer indicate good performance by the MAX-DOAS retrievals. These comparisons and modelling of the lidar S ratio highlight the need for accurate knowledge of the temporal variation in the S ratio when comparing MAX-DOAS and lidar data. Comparisons of MAX-DOAS NO2 and SO2 retrievals to Pandora spectral sun photometer vertical column densities (VCDs) and active DOAS mixing ratios indicate good performance of the retrievals, except when vertical profiles of pollutants within the boundary layer varied rapidly, temporally, and spatially. Near-surface retrievals tended to overestimate active DOAS mixing ratios. The MAX-DOAS observed elevated pollution plumes not observed by the active DOAS, highlighting one of the instrument's main advantages. Aircraft measurements of SO2 were used to validate retrieved vertical profiles of SO2. Advantages of the MAX-DOAS instrument include increasing sensitivity towards the surface and the ability to simultaneously retrieve vertical profiles of aerosols and trace gases without requiring additional parameters, such as the S ratio. This complex dataset provided a rare opportunity to evaluate the performance of the MAX-DOAS retrievals under varying atmospheric conditions.

Published
2020

50. Validation of MAX-DOAS retrievals of aerosol extinction, SO2, and NO2 through comparison with lidar, sun photometer, active DOAS, and aircraft measurements in the Athabasca oil sands region

Author

Z. Y. W. Davis, U. Frieß, K. B. Strawbridge, M. Aggarwaal, S. Baray, E. G. Schnitzler, A. Lobo, V. E. Fioletov, I. Abboud, C. A. McLinden, J. Whiteway, M. D. Willis, A. K. Y. Lee, J. Brook, J. Olfert, J. O'Brien, R. Staebler, H. D. Osthoff, C. Mihele, and R. McLaren

Subjects
lcsh:TA715-787, lcsh:Earthwork. Foundations, lcsh:TA170-171, lcsh:Environmental engineering
Abstract

Vertical profiles of aerosols, NO2, and SO2 were retrieved from Multi-Axis Differential Optical Absorption Spectroscopy (MAX-DOAS) measurements at a field site in northern Alberta, Canada, during August and September 2013. The site is approximately 16 km north of two mining operations that are major sources of industrial pollution in the Athabasca oil sands region. Pollution conditions during the study ranged from atmospheric background conditions to heavily polluted with elevated plumes, according to the meteorology. This study aimed to evaluate the performance of the aerosol and trace gas retrievals through comparison with data from a suite of other instruments. Comparisons of aerosol optical depths (AODs) from MAX-DOAS aerosol retrievals, lidar vertical profiles of aerosol extinction, and the AERONET sun photometer indicate good performance by the MAX-DOAS retrievals. These comparisons and modelling of the lidar S ratio highlight the need for accurate knowledge of the temporal variation in the S ratio when comparing MAX-DOAS and lidar data. Comparisons of MAX-DOAS NO2 and SO2 retrievals to Pandora spectral sun photometer vertical column densities (VCDs) and active DOAS mixing ratios indicate good performance of the retrievals, except when vertical profiles of pollutants within the boundary layer varied rapidly, temporally, and spatially. Near-surface retrievals tended to overestimate active DOAS mixing ratios. The MAX-DOAS observed elevated pollution plumes not observed by the active DOAS, highlighting one of the instrument's main advantages. Aircraft measurements of SO2 were used to validate retrieved vertical profiles of SO2. Advantages of the MAX-DOAS instrument include increasing sensitivity towards the surface and the ability to simultaneously retrieve vertical profiles of aerosols and trace gases without requiring additional parameters, such as the S ratio. This complex dataset provided a rare opportunity to evaluate the performance of the MAX-DOAS retrievals under varying atmospheric conditions.

Published
2020

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