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151. Tracing the evolutionary pathways of dust and cold gas in high-z quiescent galaxies with SIMBA

Author

Lorenzon, G., Donevski, D., Lisiecki, K., Lovell, C., Romano, M., Narayanan, D., Davé, R., Man, A., Whitaker, K. E., Nanni, A., Long, A., Lee, M. M., Junais, Małek, K., Rodighiero, G., and Li, Q.

Subjects
Astrophysics - Astrophysics of Galaxies
Abstract

Recent discoveries of copious amounts of dust in quiescent galaxies (QGs) at high redshifts ($z\gtrsim 1-2$) challenge the conventional view that these objects have poor interstellar medium (ISM) in proportion to their stellar mass. We use the SIMBA cosmological simulation to explore the evolution of dust and cold gas content in QGs in relation to the quenching processes affecting them. We track the changes in the ISM dust abundance across the evolutionary history of QGs identified at $0 \lesssim z \lesssim2$ in the field and cluster environments. The QGs quench via diverse pathways, both rapid and slow, and exhibit a wide range of times elapsed between the quenching event and cold gas removal (from $\sim650$ Myr to $\sim8$ Gyr). We find that quenching modes attributed to the feedback from active galactic nuclei (AGN) do not affect dust and cold gas within the same timescales. Remarkably, QGs may replenish their dust content in the quenched phase primarily due to internal processes and marginally by external factors such as minor mergers. The key mechanism for re-formation of dust is prolonged grain growth on gas-phase metals, it is effective within $\sim100$ Myr after the quenching event, and rapidly increases the dust-to-gas mass ratio in QGs above the standard values ($\delta_{\rm DGR}\gtrsim1/100$). As a result, despite heavily depleted cold gas reservoirs, roughly half of QGs maintain little evolution in their ISM dust with stellar age within the first 2 Gyr following the quenching. Overall, we predict that relatively dusty QGs ($M_{\rm dust}/M_{\star}\gtrsim10^{-3}-10^{-4}$) arise from both fast and slow quenchers, and are prevalent in systems of intermediate and low stellar masses ($9<\log(M_{\star}/M_{\odot})<10.5$). This prediction poses an immediate quest for observational synergy between e.g., James Webb Space Telescope (JWST) and the Atacama Large Millimeter Array (ALMA)., Comment: 21 pages, 10 figures, 1 table, submitted to A&A

Published
2024

152. Combined Pre-Supernova Alert System with Kamland and Super-Kamiokande

Author

KamLAND, Collaborations, Super-Kamiokande, Abe, Seisho, Eizuka, Minori, Futagi, Sawako, Gando, Azusa, Gando, Yoshihito, Goto, Shun, Hachiya, Takahiko, Hata, Kazumi, Ichimura, Koichi, Ieki, Sei, Ikeda, Haruo, Inoue, Kunio, Ishidoshiro, Koji, Kamei, Yuto, Kawada, Nanami, Kishimoto, Yasuhiro, Koga, Masayuki, Kurasawa, Maho, Mitsui, Tadao, Miyake, Haruhiko, Morita, Daisuke, Nakahata, Takeshi, Nakajima, Rika, Nakamura, Kengo, Nakamura, Rikuo, Nakamura, Ryo, Nakane, Jun, Ozaki, Hideyoshi, Saito, Keita, Sakai, Taichi, Shimizu, Itaru, Shirai, Junpei, Shiraishi, Kensuke, Shoji, Ryunosuke, Suzuki, Atsuto, Takeuchi, Atsuto, Tamae, Kyoko, Watanabe, Hiroko, Watanabe, Kazuho, Yoshida, Sei, Umehara, Saori, Fushimi, Ken-Ichi, Kotera, Kenta, Urano, Yusuke, Berger, Bruce E., Fujikawa, Brian K., Larned, John G., Maricic, Jelena, Fu, Zhenghao, Smolsky, Joseph, Winslow, Lindley A., Efremenko, Yuri, Karwowski, Hugon J., Markoff, Diane M., Tornow, Werner, Dell'Oro, Stefano, O'Donnell, Thomas, Detwiler, Jason A., Enomoto, Sanshiro, Decowski, Michal P., Weerman, Kelly M., Grant, Christopher, Song, Hasung, Li, Aobo, Axani, Spencer N., Garcia, Miles, Abe, Ko, Bronner, Christophe, Hayato, Yoshinari, Hiraide, Katsuki, Hosokawa, Keishi, Ieki, Kei, Ikeda, Motoyasu, Kameda, June, Kanemura, Yuki, Kaneshima, Ryota, Kashiwagi, Yuri, Kataoka, Yousuke, Miki, Shintaro, Mine, Shunichi, Miura, Makoto, Moriyama, Shigetaka, Nakahata, Masayuki, Nakano, Yuuki, Nakayama, Shoei, Noguchi, Yohei, Sato, Kazufumi, Sekiya, Hiroyuki, Shiba, Hayato, Shimizu, Kotaro, Shiozawa, Masato, Sonoda, Yutaro, Suzuki, Yoichiro, Takeda, Atsushi, Takemoto, Yasuhiro, Tanaka, Hidekazu K., Yano, Takatomi, Han, Seungho, Kajita, Takaaki, Okumura, Kimihiro, Tashiro, Takuya, Tomiya, Takuya, Wang, Xubin, Yoshida, Shunsuke, Fernandez, Pablo, Labarga, Luis, Ospina, Nataly, Zaldivar, Bryan, Pointon, Barry W., Kearns, Edward, Raaf, Jennifer L., Wan, Linyan, Wester, Thomas, Bian, Jianming, Griskevich, Jeff, Smy, Michael B., Sobel, Henry W., Takhistov, Volodymyr, Yankelevich, Alejandro, Hill, James, Jang, MinCheol, Lee, Seonghak, Moon, DongHo, Park, RyeongGyoon, Bodur, Baran, Scholberg, Kate, Walter, Chris W., Beauchêne, Antoine, Drapier, Olivier, Giampaolo, Alberto, Mueller, Thomas A., Santos, Andrew D., Paganini, Pascal, Quilain, Benjamin, Rogly, Rudolph, Nakamura, Taku, Jang, Jee-Seung, Machado, Lucas N., Learned, John G., Choi, Koun, Iovine, Nadege, Cao, Son V., Anthony, Lauren H. V., Martin, Daniel G. R., Prouse, Nick W., Scott, Mark, Uchida, Yoshi, Berardi, Vincenzo, Calabria, Nicola F., Catanesi, M. G., Radicioni, Emilio, Langella, Aurora, de Rosa, Gianfranca, Collazuol, Gianmaria, Feltre, Matteo, Iacob, Fabio, Mattiazzi, Marco, Ludovici, Lucio, Gonin, Michel, Périssé, Lorenzo, Pronost, Guillaume, Fujisawa, Chiori, Horiuchi, Shogo, Kobayashi, Misaki, Liu, Yu-Ming, Maekawa, Yuto, Nishimura, Yasuhiro, Okazaki, Reo, Akutsu, Ryosuke, Friend, Megan, Hasegawa, Takuya, Ishida, Taku, Kobayashi, Takashi, Jakkapu, Mahesh, Matsubara, Tsunayuki, Nakadaira, Takeshi, Nakamura, Kenzo, Oyama, Yuichi, Sakashita, Ken, Sekiguchi, Tetsuro, Tsukamoto, Toshifumi, Yrey, Antoniosk Portocarrero, Bhuiyan, Nahid, Burton, George T., Di Lodovico, Francesca, Gao, Joanna, Goldsack, Alexander, Katori, Teppei, Migenda, Jost, Ramsden, Rory M., Xie, Zhenxiong, Zsoldos, Stephane, Suzuki, Atsumu T., Takagi, Yusuke, Takeuchi, Yasuo, Zhong, Haiwen, Feng, Jiahui, Feng, Li-Cheng, Hu, Jianrun, Hu, Zhuojun, Kawaue, Masaki, Kikawa, Tatsuya, Mori, Masamitsu, Nakaya, Tsuyoshi, Wendell, Roger A., Yasutome, Kenji, Jenkins, Sam J., McCauley, Neil K., Mehta, Pruthvi, Tarrant, Adam, Wilking, Mike J., Fukuda, Yoshiyuki, Itow, Yoshitaka, Menjo, Hiroaki, Ninomiya, Kotaro, Yoshioka, Yushi, Lagoda, Justyna, Mandal, Maitrayee, Mijakowski, Piotr, Prabhu, Yashwanth S., Zalipska, Joanna, Jia, Mo, Jiang, Junjie, Shi, Wei, Yanagisawa, Chiaki, Harada, Masayuki, Hino, Yota, Ishino, Hirokazu, Koshio, Yusuke, Nakanishi, Fumi, Sakai, Seiya, Tada, Tomoaki, Tano, Tomohiro, Ishizuka, Takeharu, Barr, Giles, Barrow, Daniel, Cook, Laurence, Samani, Soniya, Wark, David, Holin, Anna, Nova, Federico, Jung, Seunghyun, Yang, Byeongsu, Yang, JeongYeol, Yoo, Jonghee, Fannon, Jack E. P., Kneale, Liz, Malek, Matthew, McElwee, Jordan M., Thiesse, Matthew D., Thompson, Lee F., Wilson, Stephen T., Okazawa, Hiroko, Mohan, Lakshmi S., Kim, SooBong, Kwon, Eunhyang, Seo, Ji-Woong, Yu, Intae, Ichikawa, Atsuko K., Nakamura, Kiseki D., Tairafune, Seidai, Nishijima, Kyoshi, Eguchi, Aoi, Nakagiri, Kota, Nakajima, Yasuhiro, Shima, Shizuka, Taniuchi, Natsumi, Watanabe, Eiichiro, Yokoyama, Masashi, de Perio, Patrick, Fujita, Saki, Jesus-Valls, Cesar, Martens, Kai, Tsui, Ka M., Vagins, Mark R., Xia, Junjie, Izumiyama, Shota, Kuze, Masahiro, Matsumoto, Ryo, Terada, Kotaro, Asaka, Ryusei, Ishitsuka, Masaki, Ito, Hiroshi, Ommura, Yuga, Shigeta, Natsuki, Shinoki, Masataka, Yamauchi, Koki, Yoshida, Tsukasa, Gaur, Rhea, Gousy-Leblan, Vincent, Hartz, Mark, Konaka, Akira, Li, Xiaoyue, Chen, Shaomin, Xu, Benda, Zhang, Aiqiang, Zhang, Bin, Posiadala-Zezula, Magdalena, Boyd, Steven B., Edwards, Rory, Hadley, David, Nicholson, Matthew, O'Flaherty, Marcus, Richards, Benjamin, Ali, Ajmi, Jamieson, Blair, Amanai, Shogo, Marti-Magro, Lluis, Minamino, Akihiro, Shibayama, Ryo, and Suzuki, Serina

Subjects
High Energy Physics - Experiment, Astrophysics - High Energy Astrophysical Phenomena, Physics - Instrumentation and Detectors
Abstract

Preceding a core-collapse supernova, various processes produce an increasing amount of neutrinos of all flavors characterized by mounting energies from the interior of massive stars. Among them, the electron antineutrinos are potentially detectable by terrestrial neutrino experiments such as KamLAND and Super-Kamiokande via inverse beta decay interactions. Once these pre-supernova neutrinos are observed, an early warning of the upcoming core-collapse supernova can be provided. In light of this, KamLAND and Super-Kamiokande, both located in the Kamioka mine in Japan, have been monitoring pre-supernova neutrinos since 2015 and 2021, respectively. Recently, we performed a joint study between KamLAND and Super-Kamiokande on pre-supernova neutrino detection. A pre-supernova alert system combining the KamLAND detector and the Super-Kamiokande detector was developed and put into operation, which can provide a supernova alert to the astrophysics community. Fully leveraging the complementary properties of these two detectors, the combined alert is expected to resolve a pre-supernova neutrino signal from a 15 M$_{\odot}$ star within 510 pc of the Earth, at a significance level corresponding to a false alarm rate of no more than 1 per century. For a Betelgeuse-like model with optimistic parameters, it can provide early warnings up to 12 hours in advance., Comment: Resubmitted to ApJ. 22 pages, 16 figures, for more information about the combined pre-supernova alert system, see https://www.lowbg.org/presnalarm/

Published
2024
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153. Expectation Alignment: Handling Reward Misspecification in the Presence of Expectation Mismatch

Author

Mechergui, Malek and Sreedharan, Sarath

Subjects
Computer Science - Artificial Intelligence, Computer Science - Machine Learning
Abstract

Detecting and handling misspecified objectives, such as reward functions, has been widely recognized as one of the central challenges within the domain of Artificial Intelligence (AI) safety research. However, even with the recognition of the importance of this problem, we are unaware of any works that attempt to provide a clear definition for what constitutes (a) misspecified objectives and (b) successfully resolving such misspecifications. In this work, we use the theory of mind, i.e., the human user's beliefs about the AI agent, as a basis to develop a formal explanatory framework called Expectation Alignment (EAL) to understand the objective misspecification and its causes. Our EAL framework not only acts as an explanatory framework for existing works but also provides us with concrete insights into the limitations of existing methods to handle reward misspecification and novel solution strategies. We use these insights to propose a new interactive algorithm that uses the specified reward to infer potential user expectations about the system behavior. We show how one can efficiently implement this algorithm by mapping the inference problem into linear programs. We evaluate our method on a set of standard Markov Decision Process (MDP) benchmarks.

Published
2024

154. Development of a data overflow protection system for Super-Kamiokande to maximize data from nearby supernovae

Author

Mori, M., Abe, K., Hayato, Y., Hiraide, K., Hosokawa, K., Ieki, K., Ikeda, M., Kameda, J., Kanemura, Y., Kaneshima, R., Kashiwagi, Y., Kataoka, Y., Miki, S., Mine, S., Miura, M., Moriyama, S., Nakano, Y., Nakahata, M., Nakayama, S., Noguchi, Y., Okamoto, K., Sato, K., Sekiya, H., Shiba, H., Shimizu, K., Shiozawa, M., Sonoda, Y., Suzuki, Y., Takeda, A., Takemoto, Y., Takenaka, A., Tanaka, H., Watanabe, S., Yano, T., Han, S., Kajita, T., Okumura, K., Tashiro, T., Tomiya, T., Wang, X., Yoshida, S., Megias, G. D., Fernandez, P., Labarga, L., Ospina, N., Zaldivar, B., Pointon, B. W., Kearns, E., Raaf, J. L., Wan, L., Wester, T., Bian, J., Griskevich, N. J., Locke, S., Smy, M. B., Sobel, H. W., Takhistov, V., Yankelevich, A., Hill, J., Jang, M. C., Lee, S. H., Moon, D. H., Park, R. G., Bodur, B., Scholberg, K., Walter, C. W., Beauchene, A., Drapier, O., Giampaolo, A., Mueller, Th. A., Santos, A. D., Paganini, P., Quilain, B., Rogly, R., Ishizuka, T., Nakamura, T., Jang, J. S., Learned, J. G., Choi, K., Iovine, N., Cao, S., Anthony, L. H. V., Martin, D., Scott, M., Sztuc, A. A., Uchida, Y., Berardi, V., Catanesi, M. G., Radicioni, E., Calabria, N. F., Langella, A., Machado, L. N., De Rosa, G., Collazuol, G., Iacob, F., Lamoureux, M., Mattiazzi, M., Ludovici, L., Gonin, M., Perisse, L., Pronost, G., Fujisawa, C., Maekawa, Y., Nishimura, Y., Okazaki, R., Akutsu, R., Friend, M., Hasegawa, T., Ishida, T., Kobayashi, T., Jakkapu, M., Matsubara, T., Nakadaira, T., Nakamura, K., Oyama, Y., Sakashita, K., Sekiguchi, T., Tsukamoto, T., Bhuiyan, N., Burton, G. T., Edwards, R., Di Lodovico, F., Gao, J., Goldsack, A., Katori, T., Migenda, J., Ramsden, R. M., Xie, Z., Zsoldos, S., Kotsar, Y., Ozaki, H., Suzuki, A. T., Takagi, Y., Takeuchi, Y., Zhong, H., Bronner, C., Feng, J., Hu, J. R., Hu, Z., Kawaune, M., Kikawa, T., LiCheng, F., Nakaya, T., Wendell, R. A., Yasutome, K., Jenkins, S. J., McCauley, N., Mehta, P., Tarant, A., Fukuda, Y., Itow, Y., Menjo, H., Ninomiya, K., Yoshioka, Y., Lagoda, J., Lakshmi, S. M., Mandal, M., Mijakowski, P., Prabhu, Y. S., Zalipska, J., Jia, M., Jiang, J., Jung, C. K., Shi, W., Wilking, M. J., Yanagisawa, C., Harada, M., Hino, Y., Ishino, H., Kitagawa, H., Koshio, Y., Nakanishi, F., Sakai, S., Tada, T., Tano, T., Barr, G., Barrow, D., Cook, L., Samani, S., Wark, D., Holin, A., Nova, F., Jung, S., Yang, B. S., Yang, J. Y., Yoo, J., Fannon, J. E. P., Kneale, L., Malek, M., McElwee, J. M., Thiesse, M. D., Thompson, L. F., Wilson, S., Okazawa, H., Kim, S. B., Kwon, E., Seo, J. W., Yu, I., Ichikawa, A. K., Nakamura, K. D., Tairafune, S., Nishijima, K., Eguchi, A., Nakagiri, K., Nakajima, Y., Shima, S., Taniuchi, N., Watanabe, E., Yokoyama, M., de Perio, P., Fujita, S., Martens, K., Tsui, K. M., Vagins, M. R., Valls, C. J., Xia, J., Kuze, M., Izumiyama, S., Ishitsuka, M., Ito, H., Kinoshita, T., Matsumoto, R., Ommura, Y., Shigeta, N., Shinoki, M., Suganuma, T., Yamauchi, K., Yoshida, T., Martin, J. F., Tanaka, H. A., Towstego, T., Gaur, R., Gousy-Leblanc, V., Hartz, M., Konaka, A., Li, X., Prouse, N. W., Chen, S., Xu, B. D., Zhang, B., Posiadala-Zezula, M., Boyd, S. B., Hadley, D., Nicholson, M., Flaherty, M. O', Richards, B., Ali, A., Jamieson, B., Amanai, S., Marti, Ll., Minamino, A., Pintaudi, G., Sano, S., Suzuki, S., and Wada, K.

Subjects
Astrophysics - Instrumentation and Methods for Astrophysics, Astrophysics - High Energy Astrophysical Phenomena, Astrophysics - Solar and Stellar Astrophysics, High Energy Physics - Experiment
Abstract

Neutrinos from very nearby supernovae, such as Betelgeuse, are expected to generate more than ten million events over 10\,s in Super-Kamokande (SK). At such large event rates, the buffers of the SK analog-to-digital conversion board (QBEE) will overflow, causing random loss of data that is critical for understanding the dynamics of the supernova explosion mechanism. In order to solve this problem, two new DAQ modules were developed to aid in the observation of very nearby supernovae. The first of these, the SN module, is designed to save only the number of hit PMTs during a supernova burst and the second, the Veto module, prescales the high rate neutrino events to prevent the QBEE from overflowing based on information from the SN module. In the event of a very nearby supernova, these modules allow SK to reconstruct the time evolution of the neutrino event rate from beginning to end using both QBEE and SN module data. This paper presents the development and testing of these modules together with an analysis of supernova-like data generated with a flashing laser diode. We demonstrate that the Veto module successfully prevents DAQ overflows for Betelgeuse-like supernovae as well as the long-term stability of the new modules. During normal running the Veto module is found to issue DAQ vetos a few times per month resulting in a total dead time less than 1\,ms, and does not influence ordinary operations. Additionally, using simulation data we find that supernovae closer than 800~pc will trigger Veto module resulting in a prescaling of the observed neutrino data., Comment: 28 pages, 18 figures. Submitted to PTEP

Published
2024
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155. Accessing the Free Expansion of a Crystalline Colloidal Drop by Optical Experiments

Author

Witt, Marcus, Nguyen, G. H. Philipp, von Puttkamer-Luerssen, Josefine R., Yilderim, Can H., Wagner, Johannes A. B., Malek, Ebrahim, Juretzka, Sabrina, Meyrelles Jr., Jorge L., Hofmann, Maximilan, Löwen, Hartmut, and Palberg, Thomas

Subjects
Condensed Matter - Soft Condensed Matter
Abstract

We study poly-crystalline spherical drops of an aqueous suspension of highly charged colloidal spheres exposed to a colloid-free aqueous environment. Crystal contours were obtained from standard optical imaging. The crystal spheres first expand to nearly four times their initial volume before slowly shrinking due to dilution-induced melting. Exploiting coherent multiple-scattering by (110) Bragg reflecting crystals, time-dependent density profiles were recorded deep within the drop interior. These show a continuously flattening radial density gradient and a decreasing central density. Expansion curves and density profiles are qualitatively consistent with theoretical expectations based on dynamical density functional theory for the expansion of a spherical crystallite made of charged Brownian spheres. We anticipate that our study opens novel experimental access to densi-ty determination in turbid crystals., Comment: Thoroughly revised version. now 23 pages with 9 figures and 57 references; supplementary materials 15 pages with 11 figures and 22 references. Accepted for publication in Soft Matter in August 2024

Published
2024

156. Enhancing Interpretability of Vertebrae Fracture Grading using Human-interpretable Prototypes

Author

Sinhamahapatra, Poulami, Shit, Suprosanna, Sekuboyina, Anjany, Husseini, Malek, Schinz, David, Lenhart, Nicolas, Menze, Joern, Kirschke, Jan, Roscher, Karsten, and Guennemann, Stephan

Subjects
Computer Science - Computer Vision and Pattern Recognition, Computer Science - Artificial Intelligence
Abstract

Vertebral fracture grading classifies the severity of vertebral fractures, which is a challenging task in medical imaging and has recently attracted Deep Learning (DL) models. Only a few works attempted to make such models human-interpretable despite the need for transparency and trustworthiness in critical use cases like DL-assisted medical diagnosis. Moreover, such models either rely on post-hoc methods or additional annotations. In this work, we propose a novel interpretable-by-design method, ProtoVerse, to find relevant sub-parts of vertebral fractures (prototypes) that reliably explain the model's decision in a human-understandable way. Specifically, we introduce a novel diversity-promoting loss to mitigate prototype repetitions in small datasets with intricate semantics. We have experimented with the VerSe'19 dataset and outperformed the existing prototype-based method. Further, our model provides superior interpretability against the post-hoc method. Importantly, expert radiologists validated the visual interpretability of our results, showing clinical applicability., Comment: Accepted for publication at the Journal of Machine Learning for Biomedical Imaging (MELBA) https://melba-journal.org/2024:015

Published
2024
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157. On three dimensional flows of viscoelastic fluids of Giesekus type

Author

Bulíček, Miroslav, Los, Tomáš, and Málek, Josef

Subjects
Mathematics - Analysis of PDEs
Abstract

Viscoelastic rate-type fluids are popular models of choice in many applications involving flows of fluid-like materials with complex micro-structure. A well-developed mathematical theory for the most of these classical fluid models is however missing. The main purpose of this study is to provide a complete proof of long-time and large-data existence of weak solutions to unsteady internal three-dimensional flows of Giesekus fluids subject to a no-slip boundary condition. As a new auxiliary tool, we provide the identification of certain biting limits in the parabolic setting, presented here within the framework of evolutionary Stokes problems. We also generalize the long-time and large-data existence result to higher dimensions, to viscoelastic models with multiple relaxation mechanisms and to viscoelastic models with different type of dissipation.

Published
2024

158. On completeness of foliated structures, and null Killing fields

Author

Hanounah, Malek and Mehidi, Lilia

Subjects
Mathematics - Differential Geometry, 53C50, 53B30
Abstract

We consider a compact manifold $(M,\mathfrak{F})$ with a foliation $\mathfrak{F}$, and a smooth affine connection $\nabla$ on the tangent bundle of the foliation $T\mathfrak{F}$. We introduce and study a foliated completeness problem. Namely, under which conditions on $\nabla$ the leaves are complete? We consider different natural geometric settings: the first one is the case of a totally geodesic lightlike foliation of a compact Lorentzian manifold, and the second one is the case where the leaves have particular affine structures. In the first case, we characterize the completeness, and obtain in particular that if a compact Lorentzian manifold admits a null Killing field $V$ such that the distribution orthogonal to $V$ is integrable, then it defines a (totally geodesic) foliation with complete leaves. In the second case, we give a completeness result for a specific affine structure called "the unimodular affine lightlike geometry", and characterize the completeness for a natural relaxation of the geometry. On the other hand, we study the global completeness of a compact Lorentzian manifold in the presence of a null Killing field. We give two non-complete examples, starting from dimension $3$: one is a locally homogeneous manifold, and the other is a $3$D example where the Killing field dynamics is equicontinuous., Comment: 23 pages, 1 figure

Published
2024

159. Effects of galaxy environment on merger fraction

Author

Pearson, W. J., Santos, D. J. D., Goto, T., Huang, T. -C., Kim, S. J., Matsuhara, H., Pollo, A., Ho, S. C. -C., Hwang, H. S., Małek, K., Nakagawa, T., Romano, M., Serjeant, S., Suelves, L., Shim, H., and White, G. J.

Subjects
Astrophysics - Astrophysics of Galaxies
Abstract

Aims. In this work, we intend to examine how environment influences the merger fraction, from the low density field environment to higher density groups and clusters. We also aim to study how the properties of a group or cluster, as well as the position of a galaxy in the group or cluster, influences the merger fraction. Methods. We identified galaxy groups and clusters in the North Ecliptic Pole using a friends-of-friends algorithm and the local density. Once identified, we determined the central galaxies, group radii, velocity dispersions, and group masses of these groups and clusters. Merging systems were identified with a neural network as well as visually. With these, we examined how the merger fraction changes as the local density changes for all galaxies as well as how the merger fraction changes as the properties of the groups or clusters change. Results. We find that the merger fraction increases as local density increases and decreases as the velocity dispersion increases, as is often found in literature. A decrease in merger fraction as the group mass increases is also found. We also find groups with larger radii have higher merger fractions. The number of galaxies in a group does not influence the merger fraction. Conclusions. The decrease in merger fraction as group mass increases is a result of the link between group mass and velocity dispersion. Hence, this decrease of merger fraction with increasing mass is a result of the decrease of merger fraction with velocity dispersion. The increasing relation between group radii and merger fraction may be a result of larger groups having smaller velocity dispersion at a larger distance from the centre or larger groups hosting smaller, infalling groups with more mergers. However, we do not find evidence of smaller groups having higher merger fractions., Comment: 15 pages, 10 figures, 8 tables, 2 appendices, accepted for publication in Astronomy & Astrophysics

Published
2024
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160. Integration of 5G and Motion Sensors for Vehicular Positioning: A Loosely-Coupled Approach

Author

Saleh, Sharief, Bader, Qamar, Karaim, Malek, Elhabiby, Mohamed, and Noureldin, Aboelmagd

Subjects
Electrical Engineering and Systems Science - Signal Processing
Abstract

Autonomous vehicles (AVs) are poised to revolutionize the transportation industry by enhancing traffic efficiency and road safety. However, achieving optimal vehicular autonomy demands an uninterrupted and precise positioning solution, especially in deep urban environments. 5G mmWave holds immense potential to provide such a service due to its accurate range and angle measurements. Yet, as mmWave signals are prone to signal blockage, severe positioning errors will occur. Most of the 5G positioning literature relies on constant motion models to bridge such 5G outages, which do not capture the true dynamics of the vehicle. Few proposed methodologies rely on inertial measurement units (IMUs) to bridge such gaps, where they predominantly use tightly coupled (TC) integration schemes, introducing a nonlinear 5G measurement model. Such approaches, which rely on Kalman filtering, necessitate the linearization of the measurement model, leading to pronounced positioning errors. In this paper, however, we propose a loosely coupled (LC) sensor fusion scheme to integrate 5G, IMUs, and odometers to mitigate linearization errors. Additionally, we propose a novel method to design the process covariance matrix of the extended Kalman filter (EKF). Moreover, we propose enhancements to the mechanization of the IMU data to enhance the standalone IMU solution. The proposed methodologies were tested using a novel setup comprising 5G measurements from Siradel's S_5G simulation tool and real IMU and odometer measurements from an hour-long trajectory. The proposed method resulted in 14 cm of error for 95% of the time compared to 1 m provided by the traditional constant velocity model approach., Comment: 12 pages, 13 figures, journal paper

Published
2024

161. Measurements of the charge ratio and polarization of cosmic-ray muons with the Super-Kamiokande detector

Author

Kitagawa, H., Tada, T., Abe, K., Bronner, C., Hayato, Y., Hiraide, K., Hosokawa, K., Ieki, K., Ikeda, M., Kameda, J., Kanemura, Y., Kaneshima, R., Kashiwagi, Y., Kataoka, Y., Miki, S., Mine, S., Miura, M., Moriyama, S., Nakano, Y., Nakahata, M., Nakayama, S., Noguchi, Y., Okamoto, K., Sato, K., Sekiya, H., Shiba, H., Shimizu, K., Shiozawa, M., Sonoda, Y., Suzuki, Y., Takeda, A., Takemoto, Y., Takenaka, A., Tanaka, H., Watanabe, S., Yano, T., Han, S., Kajita, T., Okumura, K., Tashiro, T., Tomiya, T., Wang, X., Yoshida, S., Megias, G. D., Fernandez, P., Labarga, L., Ospina, N., Zaldivar, B., Pointon, B. W., Kearns, E., Raaf, J. L., Wan, L., Wester, T., Bian, J., Griskevich, N. J., Locke, S., Smy, M. B., Sobel, H. W., Takhistov, V., Yankelevich, A., Hill, J., Jang, M. C., Lee, S. H., Moon, D. H., Park, R. G., Bodur, B., Scholberg, K., Walter, C. W., Beauchêne, A., Drapier, O., Giampaolo, A., Mueller, Th. A., Santos, A. D., Paganini, P., Quilain, B., Rogly, R., Nakamura, T., Jang, J. S., Machado, L. N., Learned, J. G., Choi, K., Iovine, N., Cao, S., Anthony, L. H. V., Martin, D., Prouse, N. W., Scott, M., Sztuc, A. A., Uchida, Y., Berardi, V., Calabria, N. F., Catanesi, M. G., Radicioni, E., Langella, A., De Rosa, G., Collazuol, G., Iacob, F., Lamoureux, M., Mattiazzi, M., Ludovici, L., Gonin, M., Périssé, L., Pronost, G., Fujisawa, C., Maekawa, Y., Nishimura, Y., Okazaki, R., Akutsu, R., Friend, M., Hasegawa, T., Ishida, T., Kobayashi, T., Jakkapu, M., Matsubara, T., Nakadaira, T., Nakamura, K., Oyama, Y., Sakashita, K., Sekiguchi, T., Tsukamoto, T., Bhuiyan, N., Burton, G. T., Di Lodovico, F., Gao, J., Goldsack, A., Katori, T., Migenda, J., Ramsden, R. M., Xie, Z., Zsoldos, S., Kotsar, Y., Ozaki, H., Suzuki, A. T., Takagi, Y., Takeuchi, Y., Zhong, H., Feng, J., Feng, L., Hu, J. R., Hu, Z., Kawaue, M., Kikawa, T., Mori, M., Nakaya, T., Wendell, R. A., Yasutome, K., Jenkins, S. J., McCauley, N., Mehta, P., Tarant, A., Wilking, M. J., Fukuda, Y., Itow, Y., Menjo, H., Ninomiya, K., Yoshioka, Y., Lagoda, J., Mandal, M., Mijakowski, P., Prabhu, Y. S., Zalipska, J., Jia, M., Jiang, J., Jung, C. K., Shi, W., Yanagisawa, C., Harada, M., Hino, Y., Ishino, H., Koshio, Y., Nakanishi, F., Sakai, S., Tano, T., Ishizuka, T., Barr, G., Barrow, D., Cook, L., Samani, S., Wark, D., Holin, A., Nova, F., Jung, S., Yang, B. S., Yang, J. Y., Yoo, J., Fannon, J. E. P., Kneale, L., Malek, M., McElwee, J. M., Thiesse, M. D., Thompson, L. F., Wilson, S. T., Okazawa, H., Lakshmi, S. M., Kim, S. B., Kwon, E., Seo, J. W., Yu, I., Ichikawa, A. K., Nakamura, K. D., Tairafune, S., Nishijima, K., Eguchi, A., Nakagiri, K., Nakajima, Y., Shima, S., Taniuchi, N., Watanabe, E., Yokoyama, M., de Perio, P., Fujita, S., Jesús-Valls, C., Martens, K., Tsui, K. M., Vagins, M. R., Xia, J., Izumiyama, S., Kuze, M., Matsumoto, R., Terada, K., Ishitsuka, M., Ito, H., Kinoshita, T., Ommura, Y., Shigeta, N., Shinoki, M., Suganuma, T., Yamauchi, K., Yoshida, T., Martin, J. F., Tanaka, H. A., Towstego, T., Gaur, R., Gousy-Leblanc, V., Hartz, M., Konaka, A., Li, X., Chen, S., Xu, B. D., Zhang, B., Posiadala-Zezula, M., Boyd, S. B., Edwards, R., Hadley, D., Nicholson, M., O'Flaherty, M., Richards, B., Ali, A., Jamieson, B., Amanai, S., Marti, Ll., Minamino, A., Pintaudi, G., Sano, S., Suzuki, S., and Wada, K.

Subjects
High Energy Physics - Experiment, Astrophysics - High Energy Astrophysical Phenomena
Abstract

We present the results of the charge ratio ($R$) and polarization ($P^{\mu}_{0}$) measurements using the decay electron events collected from 2008 September to 2022 June by the Super-Kamiokande detector. Because of its underground location and long operation, we performed high precision measurements by accumulating cosmic-ray muons. We measured the muon charge ratio to be $R=1.32 \pm 0.02$ $(\mathrm{stat.}{+}\mathrm{syst.})$ at $E_{\mu}\cos \theta_{\mathrm{Zenith}}=0.7^{+0.3}_{-0.2}$ $\mathrm{TeV}$, where $E_{\mu}$ is the muon energy and $\theta_{\mathrm{Zenith}}$ is the zenith angle of incoming cosmic-ray muons. This result is consistent with the Honda flux model while this suggests a tension with the $\pi K$ model of $1.9\sigma$. We also measured the muon polarization at the production location to be $P^{\mu}_{0}=0.52 \pm 0.02$ $(\mathrm{stat.}{+}\mathrm{syst.})$ at the muon momentum of $0.9^{+0.6}_{-0.1}$ $\mathrm{TeV}/c$ at the surface of the mountain; this also suggests a tension with the Honda flux model of $1.5\sigma$. This is the most precise measurement ever to experimentally determine the cosmic-ray muon polarization near $1~\mathrm{TeV}/c$. These measurement results are useful to improve the atmospheric neutrino simulations., Comment: 29 pages, 45 figures

Published
2024
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162. Second gadolinium loading to Super-Kamiokande

Author

Abe, K., Bronner, C., Hayato, Y., Hiraide, K., Hosokawa, K., Ieki, K., Ikeda, M., Kameda, J., Kanemura, Y., Kaneshima, R., Kashiwagi, Y., Kataoka, Y., Miki, S., Mine, S., Miura, M., Moriyama, S., Nakano, Y., Nakahata, M., Nakayama, S., Noguchi, Y., Sato, K., Sekiya, H., Shiba, H., Shimizu, K., Shiozawa, M., Sonoda, Y., Suzuki, Y., Takeda, A., Takemoto, Y., Tanaka, H., Yano, T., Han, S., Kajita, T., Okumura, K., Tashiro, T., Tomiya, T., Wang, X., Yoshida, S., Fernandez, P., Labarga, L., Ospina, N., Zaldivar, B., Pointon, B. W., Kearns, E., Raaf, J. L., Wan, L., Wester, T., Bian, J., Griskevich, N. J., Smy, M. B., Sobel, H. W., Takhistov, V., Yankelevich, A., Hill, J., Jang, M. C., Lee, S. H., Moon, D. H., Park, R. G., Bodur, B., Scholberg, K., Walter, C. W., Beauchene, A., Drapier, O., Giampaolo, A., Mueller, Th. A., Santos, A. D., Paganini, P., Quilain, B., Rogly, R., Nakamura, T., Jang, J. S., Machado, L. N., Learned, J. G., Choi, K., Iovine, N., Cao, S., Anthony, L. H. V., Martin, D., Prouse, N. W., Scott, M., Uchida, Y., Berardi, V., Calabria, N. F., Catanesi, M. G., Radicioni, E., Langella, A., De Rosa, G., Collazuol, G., Iacob, F., Mattiazzi, M., Ludovici, L., Gonin, M., Perisse, L., Pronost, G., Fujisawa, C., Maekawa, Y., Nishimura, Y., Okazaki, R., Akutsu, R., Friend, M., Hasegawa, T., Ishida, T., Kobayashi, T., Jakkapu, M., Matsubara, T., Nakadaira, T., Nakamura, K., Oyama, Y., Sakashita, K., Sekiguchi, T., Tsukamoto, T., Bhuiyan, N., Burton, G. T., Di Lodovico, F., Gao, J., Goldsack, A., Katori, T., Migenda, J., Ramsden, R. M., Xie, Z., Zsoldos, S., Suzuki, A. T., Takagi, Y., Takeuchi, Y., Zhong, H., Feng, J., Feng, L., Hu, J. R., Hu, Z., Kawaue, M., Kikawa, T., Mori, M., Nakaya, T., Wendell, R. A., Yasutome, K., Jenkins, S. J., McCauley, N., Mehta, P., Tarant, A., Wilking, M. J., Fukuda, Y., Itow, Y., Menjo, H., Ninomiya, K., Yoshioka, Y., Lagoda, J., Mandal, M., Mijakowski, P., Prabhu, Y. S., Zalipska, J., Jia, M., Jiang, J., Shi, W., Yanagisawa, C., Harada, M., Hino, Y., Ishino, H., Koshio, Y., Nakanishi, F., Sakai, S., Tada, T., Tano, T., Ishizuka, T., Barr, G., Barrow, D., Cook, L., Samani, S., Wark, D., Holin, A., Nova, F., Jung, S., Yang, B. S., Yang, J. Y., Yoo, J., Fannon, J. E. P., Kneale, L., Malek, M., McElwee, J. M., Thiesse, M. D., Thompson, L. F., Wilson, S. T., Okazawa, H., Lakshmi, S. M., Kim, S. B., Kwon, E., Seo, J. W., Yu, I., Ichikawa, A. K., Tairafune, S., Nishijima, K., Eguchi, A., Nakagiri, K., Nakajima, Y., Shima, S., Taniuchi, N., Watanabe, E., Yokoyama, M., de Perio, P., Fujita, S., Jesus-Valls, C., Martens, K., Tsui, K. M., Vagins, M. R., Xia, J., Izumiyama, S., Kuze, M., Matsumoto, R., Terada, K., Ishitsuka, M., Ito, H., Ommura, Y., Shigeta, N., Shinoki, M., Yamauchi, K., Yoshida, T., Gaur, R., Gousy-Leblanc, V., Hartz, M., Konaka, A., Li, X., Chen, S., Xu, B. D., Zhang, B., Posiadala-Zezula, M., Boyd, S. B., Edwards, R., Hadley, D., Nicholson, M., O'Flaherty, M., Richards, B., Ali, A., Jamieson, B., Amanai, S., Marti, Ll., Minamino, A., Suzuki, S., Scovell, P. R., Meehan, E., Bandac, I., Pena-Garay, C., Perez, J., Gileva, O., Lee, E. K., Leonard, D. S., Sakakieda, Y., Sakaguchi, A., Sueki, K., Takaku, Y., and Yamasaki, S.

Subjects
Physics - Instrumentation and Detectors, Astrophysics - High Energy Astrophysical Phenomena
Abstract

The first loading of gadolinium (Gd) into Super-Kamiokande in 2020 was successful, and the neutron capture efficiency on Gd reached 50\%. To further increase the Gd neutron capture efficiency to 75\%, 26.1 tons of $\rm Gd_2(\rm SO_4)_3\cdot \rm 8H_2O$ was additionally loaded into Super-Kamiokande (SK) from May 31 to July 4, 2022. As the amount of loaded $\rm Gd_2(\rm SO_4)_3\cdot \rm 8H_2O$ was doubled compared to the first loading, the capacity of the powder dissolving system was doubled. We also developed new batches of gadolinium sulfate with even further reduced radioactive impurities. In addition, a more efficient screening method was devised and implemented to evaluate these new batches of $\rm Gd_2(\rm SO_4)_3\cdot \rm 8H_2O$. Following the second loading, the Gd concentration in SK was measured to be $333.5\pm2.5$ ppm via an Atomic Absorption Spectrometer (AAS). From the mean neutron capture time constant of neutrons from an Am/Be calibration source, the Gd concentration was independently measured to be 332.7 $\pm$ 6.8(sys.) $\pm$ 1.1(stat.) ppm, consistent with the AAS result. Furthermore, during the loading the Gd concentration was monitored continually using the capture time constant of each spallation neutron produced by cosmic-ray muons,and the final neutron capture efficiency was shown to become 1.5 times higher than that of the first loaded phase, as expected., Comment: 34 pages, 13 figures, submitted to Nuclear Inst. and Methods in Physics Research, A

Published
2024
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163. Performance of SK-Gd's Upgraded Real-time Supernova Monitoring System

Author

Kashiwagi, Y., Abe, K., Bronner, C., Hayato, Y., Hiraide, K., Hosokawa, K., Ieki, K., Ikeda, M., Kameda, J., Kanemura, Y., Kaneshima, R., Kataoka, Y., Miki, S., Mine, S., Miura, M., Moriyama, S., Nakano, Y., Nakahata, M., Nakayama, S., Noguchi, Y., Sato, K., Sekiya, H., Shiba, H., Shimizu, K., Shiozawa, M., Sonoda, Y., Suzuki, Y., Takeda, A., Takemoto, Y., Tanaka, H., Yano, T., Han, S., Kajita, T., Okumura, K., Tashiro, T., Tomiya, T., Wang, X., Yoshida, S., Fernandez, P., Labarga, L., Ospina, N., Zaldivar, B., Pointn, B. W., Kearns, E., Raaf, J. L., Wan, L., Wester, T., Bian, J., Griskevich, N. J., Locke, S., Smy, M. B., Sobel, H. W., Takhistov, V., Yankelevich, A., Hill, J., Jang, M. C., Lee, S. H., Moon, D. H., Park, R. G., Bodur, B., Scholberg, K., Walter, C. W., Beauchêne, A., Drapier, O., Giampaolo, A., Mueller, Th. A., Santos, A. D., Paganini, P., Quilain, B., Rogly, R., Nakamura, T., Jang, J. S., Machado, L. N., Learned, J. G., Choi, K., Iovine, N., Cao, S., Anthony, L. H. V., Martin, D., Prouse, N. W., Scott, M., Sztuc, A. A., Uchida, Y., Berardi, V., Catanesi, M. G., Radicioni, E., Calabria, N. F., Langella, A., De Rosa, G., Collazuol, G., Iacob, F., Mattiazzi, M., Ludovici, L., Gonin, M., Périssé, L., Pronost, G., Fujisawa, C., Maekawa, Y., Nishimura, Y., Okazaki, R., Akutsu, R., Friend, M., Hasegawa, T., Ishida, T., Kobayashi, T., Jakkapu, M., Matsubara, T., Nakadaira, T., Nakamura, K., Oyama, Y., Sakashita, K., Sekiguchi, T., Tsukamoto, T., Bhuiyan, N., Burton, G. T., Di Lodovico, F., Gao, J., Goldsack, A., Katori, T., Migenda, J., Ramsden, R. M., Xie, Z., Zsoldos, S., Suzuki, A. T., Takagi, Y., Takeuchi, Y., Zhong, H., Feng, J., Feng, L., Hu, J. R., Hu, Z., Kawaue, M., Kikawa, T., Mori, M., Nakaya, T., Wendell, R. A., Yasutome, K., Jenkins, S. J., McCauley, N., Mehta, P., Tarrant, A., Fukuda, Y., Itow, Y., Menjo, H., Ninomiya, K., Yoshioka, Y., Lagoda, J., Lakshmi, S. M., Mandal, M., Mijakowski, P., Prabhu, Y. S., Zalipska, J., Jia, M., Jiang, J., Jung, C. K., Shi, W., Wilking, M. J., Yanagisawa, C., Harada, M., Hino, Y., Ishino, H., Koshio, Y., Nakanishi, F., Sakai, S., Tada, T., Tano, T., Ishizuka, T., Barr, G., Barrow, D., Cook, L., Samani, S., Wark, D., Holin, A., Nova, F., Jung, S., Yang, B. S., Yang, J. Y., Yoo, J., Fannon, J. E. P., Kneale, L., Malek, M., McElwee, J. M., Thiesse, M. D., Thompson, L. F., Wilson, S. T., Okazawa, H., Kim, S. B., Kwon, E., Seo, J. W., Yu, I., Ichikawa, A. K., Nakamura, K. D., Tairafune, S., Nishijima, K., Eguchi, A., Nakagiri, K., Nakajima, Y., Shima, S., Taniuchi, N., Watanabe, E., Yokoyama, M., de Perio, P., Fujita, S., Jesús-Valls, C., Martens, K., Tsui, K. M., Vagins, M. R., Xia, J., Kuze, M., Izumiyama, S., Matsumoto, R., Ishitsuka, M., Ito, H., Ommura, Y., Shigeta, N., Shinoki, M., Yamauchi, K., Yoshida, T., Gaur, R., Gousy-Leblanc, V., Hartz, M., Konaka, A., Li, X., Chen, S., Xu, B. D., Zhang, B., Posiadala-Zezula, M., Boyd, S. B., Edwards, R., Hadley, D., Nicholson, M., O'Flaherty, M., Richards, B., Ali, A., Jamieson, B., Amanai, S., Marti, Ll., Minamino, A., and Suzuki, S.

Subjects
Astrophysics - High Energy Astrophysical Phenomena
Abstract

Among multi-messenger observations of the next galactic core-collapse supernova, Super-Kamiokande (SK) plays a critical role in detecting the emitted supernova neutrinos, determining the direction to the supernova (SN), and notifying the astronomical community of these observations in advance of the optical signal. On 2022, SK has increased the gadolinium dissolved in its water target (SK-Gd) and has achieved a Gd concentration of 0.033%, resulting in enhanced neutron detection capability, which in turn enables more accurate determination of the supernova direction. Accordingly, SK-Gd's real-time supernova monitoring system (Abe te al. 2016b) has been upgraded. SK_SN Notice, a warning system that works together with this monitoring system, was released on December 13, 2021, and is available through GCN Notices (Barthelmy et al. 2000). When the monitoring system detects an SN-like burst of events, SK_SN Notice will automatically distribute an alarm with the reconstructed direction to the supernova candidate within a few minutes. In this paper, we present a systematic study of SK-Gd's response to a simulated galactic SN. Assuming a supernova situated at 10 kpc, neutrino fluxes from six supernova models are used to characterize SK-Gd's pointing accuracy using the same tools as the online monitoring system. The pointing accuracy is found to vary from 3-7$^\circ$ depending on the models. However, if the supernova is closer than 10 kpc, SK_SN Notice can issue an alarm with three-degree accuracy, which will benefit follow-up observations by optical telescopes with large fields of view., Comment: 38 pages, 29 figures, 6 tables

Published
2024

165. Memory based cuckoo search algorithm for feature selection of gene expression dataset

Author

Malek Alzaqebah, PhD, Khaoula Briki, Nashat Alrefai, Sami Brini, Sana Jawarneh, Mutasem K. Alsmadi, Rami Mustafa A. Mohammad, Ibrahim ALmarashdeh, Fahad A. Alghamdi, Nahier Aldhafferi, and Abdullah Alqahtani

Subjects
Cuckoo-search-algorithm, Feature-selection, Classification, Microarray, Cancer-prediction and memory-based-methods, Computer applications to medicine. Medical informatics, R858-859.7
Abstract

Cancer prediction has been shown to be important in the cancer research area. This importance has prompted many researchers to review machine learning-approaches to predict cancer outcome using gene expression dataset. This dataset consists of many genes (features) which can mislead the prediction ability of the machine learning methods, as some features may lead to confusion or inaccurate classification. Since finding the most informative genes for cancer prediction is challenging, feature selection techniques are recommended to pick important and relevant features out of large and complex datasets. In this research, we propose the Cuckoo search method as a feature selection algorithm, guided by the memory-based mechanism to save the most informative features that are identified by the best solutions. The purpose of the memory is to keep track of the selected features at every iteration and find the features that enhance classification accuracy. The suggested algorithm has been contrasted with the original algorithm using microarray datasets and the proposed algorithm has been shown to produce good results as compared to original and contemporary algorithms.

Published
2021
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166. Digitalization of learning in Saudi Arabia during the COVID-19 outbreak: A survey

Author

Mutasem K. Alsmadi, Ibrahim Al-Marashdeh, Malek Alzaqebah, Ghaith Jaradat, Fahad A. Alghamdi, Rami Mustafa A Mohammad, Muneerah Alshabanah, Daniah Alrajhi, Hanouf Alkhaldi, Nahier Aldhafferi, Abdullah Alqahtani, Usama A. Badawi, and Mohammed Tayfour

Subjects
COVID-19, Online learning, Educational technologies, Novel coronavirus, Computer applications to medicine. Medical informatics, R858-859.7
Abstract

Following the outbreak of the novel coronavirus (COVID-19) in China in late December 2019, more than 217 countries became almost immediately infected in the resulting pandemic. Consequently, many of them decided to close their educational institutions as a way of preventing the spread of this virus. For many of them, though, the closure made them unable to deliver learning materials to students owing to their inability to provide the right technology for the purpose. To assist with the digitalizing of learning during this time, this study reviews the most common technologies used in the delivery of learning materials, with the experience of most infected countries being considered. Major challenges in online learning are discussed in this study as well. Further, Saudi Arabia was considered as a case study for the effectiveness of distance learning during the 2020 spring semester, where 300 undergraduate students were surveyed on their opinions of distance learning. The responses to the survey indicated that distance learning was effective in providing the required knowledge to the students during the outbreak of COVID-19. The findings showed that although the lack of interaction and poor internet connections were factors affecting comfortable and successful learning of physics and mathematics, 63% of students were satisfied with learning management systems, 75% of students found it easy to understand course materials, and 67% of students found it easy to understand assignments and could deal with them comfortably. The study findings can encourage educational institutions to digitalize their learning materials in the future.

Published
2021
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170. Community standards and future opportunities for synthetic communities in plant–microbiota research

Author

Northen, Trent R., Kleiner, Manuel, Torres, Marta, Kovács, Ákos T., Nicolaisen, Mette Haubjerg, Krzyżanowska, Dorota M., Sharma, Shilpi, Lund, George, Jelsbak, Lars, Baars, Oliver, Kindtler, Nikolaj Lunding, Wippel, Kathrin, Dinesen, Caja, Ferrarezi, Jessica A., Marian, Malek, Pioppi, Adele, Xu, Xinming, Andersen, Tonni, Geldner, Niko, Schulze-Lefert, Paul, Vorholt, Julia A., and Garrido-Oter, Ruben

Published
2024
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177. The rise and transformation of Bronze Age pastoralists in the Caucasus

Author

Ghalichi, Ayshin, Reinhold, Sabine, Rohrlach, Adam B., Kalmykov, Alexey A., Childebayeva, Ainash, Yu, He, Aron, Franziska, Semerau, Lena, Bastert-Lamprichs, Katrin, Belinskiy, Andrey B., Berezina, Natalia Y., Berezin, Yakov B., Broomandkhoshbacht, Nasreen, Buzhilova, Alexandra P., Erlikh, Vladimir R., Fehren-Schmitz, Lars, Gambashidze, Irina, Kantorovich, Anatoliy R., Kolesnichenko, Konstantin B., Lordkipanidze, David, Magomedov, Rabadan G., Malek-Custodis, Katharina, Mariaschk, Dirk, Maslov, Vladimir E., Mkrtchyan, Levon, Nagler, Anatoli, Fazeli Nashli, Hassan, Ochir, Maria, Piotrovskiy, Yuri Y., Saribekyan, Mariam, Sheremetev, Aleksandr G., Stöllner, Thomas, Thomalsky, Judith, Vardanyan, Benik, Posth, Cosimo, Krause, Johannes, Warinner, Christina, Hansen, Svend, and Haak, Wolfgang

Published
2024
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181. Association of ACE1 I/D polymorphism and susceptibility to COVID-19 in Egyptian children and adolescents

Author

Boraey, Naglaa F., Bebars, Marwa A., Wahba, Ali A., Abd El Lateef, Hanan M., Attia, Mohamed Atif, Elsayed, Ahmed H., Rashed, Khalid A., Sorour, Ehab I., Ahmed, Mohamed F., Abd-Elrehim, Ghada A. B., Soliman, Attia A., Shehab, Mohamed M. M., Elhindawy, Eman M., Ibraheem, Ahmed A. A., Shehata, Hassan, Yousif, Yousif M., Hashem, Mustafa I. A., Ahmed, Amani A., Emam, Ahmed A., Gameil, Dalia M., Abdelhady, Eman M., Abdelkhalek, Khalil, Morsi, Walaa E. M. A., Selim, Dalia M., Razek, Suzan A., Ashraf, Bassem, Saleh, Ahmed S. E., Eltrawy, Heba H., Alanwar, Mohamed I., Fouad, Rania A., Omar, Walaa E., Nabil, Rehab M., Abdelhamed, Mohamed R., Ibrahim, Mona Yousri, Malek, Mai M., Afify, Mona R., Alharbi, Mohanned T., Nagshabandi, Mohammed K., Tarabulsi, Muyassar K., Qashqary, Mohammed Esmail, Almoraie, Laila M., Salem, Hanan F., Rashad, Manal M., El-Gaaly, Sonya A. A., El- Deeb, Nahawand A., Abdallah, Amany M., Fakhreldin, Ahmed R., Hassouba, Mohamed, Massoud, Yasmine M., Attaya, Mona S. M., and Haridi, Mohammed K.

Published
2024
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182. Integrated image-based deep learning and language models for primary diabetes care

Author

Li, Jiajia, Guan, Zhouyu, Wang, Jing, Cheung, Carol Y., Zheng, Yingfeng, Lim, Lee-Ling, Lim, Cynthia Ciwei, Ruamviboonsuk, Paisan, Raman, Rajiv, Corsino, Leonor, Echouffo-Tcheugui, Justin B., Luk, Andrea O. Y., Chen, Li Jia, Sun, Xiaodong, Hamzah, Haslina, Wu, Qiang, Wang, Xiangning, Liu, Ruhan, Wang, Ya Xing, Chen, Tingli, Zhang, Xiao, Yang, Xiaolong, Yin, Jun, Wan, Jing, Du, Wei, Quek, Ten Cheer, Goh, Jocelyn Hui Lin, Yang, Dawei, Hu, Xiaoyan, Nguyen, Truong X., Szeto, Simon K. H., Chotcomwongse, Peranut, Malek, Rachid, Normatova, Nargiza, Ibragimova, Nilufar, Srinivasan, Ramyaa, Zhong, Pingting, Huang, Wenyong, Deng, Chenxin, Ruan, Lei, Zhang, Cuntai, Zhang, Chenxi, Zhou, Yan, Wu, Chan, Dai, Rongping, Koh, Sky Wei Chee, Abdullah, Adina, Hee, Nicholas Ken Yoong, Tan, Hong Chang, Liew, Zhong Hong, Tien, Carolyn Shan-Yeu, Kao, Shih Ling, Lim, Amanda Yuan Ling, Mok, Shao Feng, Sun, Lina, Gu, Jing, Wu, Liang, Li, Tingyao, Cheng, Di, Wang, Zheyuan, Qin, Yiming, Dai, Ling, Meng, Ziyao, Shu, Jia, Lu, Yuwei, Jiang, Nan, Hu, Tingting, Huang, Shan, Huang, Gengyou, Yu, Shujie, Liu, Dan, Ma, Weizhi, Guo, Minyi, Guan, Xinping, Yang, Xiaokang, Bascaran, Covadonga, Cleland, Charles R., Bao, Yuqian, Ekinci, Elif I., Jenkins, Alicia, Chan, Juliana C. N., Bee, Yong Mong, Sivaprasad, Sobha, Shaw, Jonathan E., Simó, Rafael, Keane, Pearse A., Cheng, Ching-Yu, Tan, Gavin Siew Wei, Jia, Weiping, Tham, Yih-Chung, Li, Huating, Sheng, Bin, and Wong, Tien Yin

Published
2024
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192. Strengthening education and training programmes for medical physics in Asia and the Pacific: the IAEA non-agreement technical cooperation (TC) regional RAS6088 project

Author

Jamal, Noriah, Krisanachinda, Anchali, Tsapaki, Virginia, Islam, Md Rafiqul, Pawiro, Supriyanto, Al Omari, Muhammad, Yeong, Chai Hong, Myint, Thinn Thinn, Kakakhel, Muhammad Basim, Kharita, Mohammad Hassan, Lee, Cheow Lei James, Ismail, Anas, Nguyen, Thanh Binh, Knoll, Peter, Ciraj-Bjelac, Olivera, and Malek, Massoud

Published
2024
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196. Multiscale Characterization of Type I Collagen Fibril Stress–Strain Behavior under Tensile Load: Analytical vs. MD Approaches

Author

Afif Gouissem, Raouf Mbarki, Fadi Al Khatib, and Malek Adouni

Subjects
analytical formulation, coarse-grained model, collagen, crosslinks, fibril, stress–strain curve, Technology, Biology (General), QH301-705.5
Abstract

Type I collagen is one of the most important proteins in the human body because of its role in providing structural support to the extracellular matrix of the connective tissues. Understanding its mechanical properties was widely investigated using experimental testing as well as molecular and finite element simulations. In this work, we present a new approach for defining the properties of the type I collagen fibrils by analytically formulating its response when subjected to a tensile load and investigating the effects of enzymatic crosslinks on the behavioral response. We reveal some of the shortcomings of the molecular dynamics (MD) method and how they affect the obtained stress–strain behavior of the fibril, and we prove that not only does MD underestimate the Young’s modulus and the ultimate tensile strength of the collagen fibrils, but also fails to detect the mechanics of some stretching phases of the fibril. We prove that non-crosslinked fibrils have three tension phases: (i) an initial elastic deformation corresponding to the collagen molecule uncoiling, (ii) a linear regime related to the stretching of the backbone of the tropocollagen molecules, and (iii) a plastic regime dominated by molecular sliding. We also show that for crosslinked fibrils, the second regime can be subdivided into three sub-regimes, and we define the properties of each regime. We also prove, analytically, the alleged MD quadratic relation between the ultimate tensile strength of the fibril and the concentration of enzymatic crosslinks (β).

Published
2022
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197. Insecticide Susceptibility Status of Wild Population of Phlebotomus kandelakii and Phlebotomus perfiliewi transcaucasicus Collected from Visceral Leishmaniasis Endemic Foci in Northwestern Iran

Author

Yavar Rassi, Eslam Moradi-Asl, Hassan Vatandoost, Malek Abazari, and Abedin Saghafipour

Subjects
Phlebotomus kandelakii, Phlebotomus perfiliewi transcaucasicus, Insecticide resistance, Insecticide sus¬ceptibility, Lambda-cyhalothrin, Pathology, RB1-214
Abstract

Background: Phlebotomus kandelakii and Phlebotomus perfiliewi transcaucasicus sand flies are the vectors of vis­ceral leishmaniasis in Iran. The aim of this study was to evaluate the susceptibility of Ph. kandelakii and Ph. perfil­iewi trans­caucasicus, collected from an endemic focus of visceral leishmaniasis (VL) in the northwest of Iran, to different select­ed insecticides. Methods: Sand flies were collected from the villages of Meshkinshahr and Germi Counties using light traps and aspira­tors from May to October 2019. The sand flies were identified as Ph. kandelakii and Ph. perfiliewi transcauca­sicus us­ing standard identification keys. Susceptibility test was carried out against DDT (4%), Malathion (5%), Propoxur (0.1%) and Lambda-cyhalothrin (0.05%) according to the WHO standard method. MedCalc statistical software was employed to calculate LT50 and LT90 and to compare the chances of sand flies surviving the exposure to the studied in­secticides. Results: A total of 1,278 female specimens were used for the susceptibility tests. Out of which 1,063 samples were used for the test and 215 for the control group. The estimated LT50 values for DDT (4%), Malathion (5%), Propoxur (0.1%), and Lambda-cyhalothrin (0.05%) for Ph. kandelakii were 15.1, 13.4, 15.4 and 5.8 minutes respectively, and for Ph. per­filiewi transcaucasicus were 11.9, 15.6, 15.9 and 5.8 minutes respectively. Conclusion: This susceptibility studies revealed different LT50 values for different insecticides efficient against Ph. kandelakii and Ph. perfiliewi transcaucasicus. The regular monitoring for the resistance of Ph. kandelakii and Ph. per­filiewi transcaucasicus sand flies seems necessary in diseases control programs in this area.

Published
2020
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198. A Home in Disorder is not a Home: Examining Race in Trinidad and Tobago

Author

Malek Abdel-Shehid

Subjects
History of scholarship and learning. The humanities, AZ20-999, Social Sciences, Education
Abstract

Among its neighbours, the island nation of Trinidad and Tobago stands out due to its ethnic makeup. The population of most Caribbean nations is mainly of African descent; similar to Guyana, Trinidad and Tobago is evenly divided between Afro-Trinidadians and Indo-Trinidadians. Unlike many of the other Caribbean colonies, Trinidad and Tobago were not extensive plantation economies until much later in the colonial period (Paton 291). This is one of the main reasons why the country presently hosts a proportionately lower Afro-Trinidadian population in comparison to other Caribbean countries. While other ethno-cultural groups reside in the country, the aforementioned groups have dominated the landscape in numbers since at least the early 20th century (United Nations Statistics Division). Afro-Trinidadians are generally descendants of enslaved Africans brought to the Caribbean to serve as plantation labourers; Indo-Trinidadians are generally the descendants of South Asian indentured labourers brought to Trinidad to fulfill the same role following the abolition of slavery in the British West Indies. Trinidad and Tobago's long history of colonial subjugation has bred a modern social hierarchy highly tied to race. Racial categories centered around physical characteristics and created during the colonial period have been instrumental in the development of this social hierarchy. Its institutionalization within the country’s modern national political system has resulted in persisting legacies evident throughout modern Trinidadian society. I focus on the island of Trinidad (while still making occasional reference to Tobago) and argue that Trinidadian national unity has been hampered by the foundations laid by the plantation system and consolidated by the modern political system.

Published
2020
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199. From Trinidad and Tobago to the World: Determining the role of Calypso in a new Era

Author

Malek Abdel-Shehid

Subjects
History of scholarship and learning. The humanities, AZ20-999, Social Sciences, Education
Abstract

Calypso is a popular Caribbean musical genre that originated in the island nation of Trinidad and Tobago. The genre was developed primarily by enslaved West Africans brought to the region via the transatlantic slave trade during the seventeenth and eighteenth centuries. Although West-African Kaiso music was a major influence, the genre has also been shaped by other African genres, and by Indian, British, French, and Spanish musical cultures. Emerging in the early twentieth century, Calypso became a tool of resistance by Afro-Caribbean working-class Trinbagonians. Calypso flourished in Trinidad due to a combination of factors—namely, the migration of Afro-Caribbean people from across the region in search of upward social mobility. These people sought to expose the injustices perpetrated by a foreign European and a domestic elite against labourers in industries such as petroleum extraction. The genre is heavily anti-colonial, anti-imperial, and anti-elitist, and it advocated for regional integration. Although this did not occur immediately, Calypsonians sought to establish unity across the region regardless of race, nationality, and class through their songwriting and performing. Today, Calypso remains a unifying force and an important part of Caribbean culture. Considering Calypso's history and purpose, as well as its ever-changing creators and audiences, this essay will demonstrate that the goal of regional integration is not possible without cultural sovereignty.

Published
2020
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200. The Relationship between Quality of Life and Physical Activity, Worry, Depression, and Insomnia in Pregnant Women

Author

Davoud Adham and Malek Abazari

Subjects
Depression, Insomnia, Pregnant Women, Physical Activity, Quality of life, Worry, Psychiatry, RC435-571
Abstract

Objective: Physical activity (PA), insomnia, depression, and worry were the key factors affecting pregnant women’s quality of life (QoL). The present study aimed to determine quality of life and its relationship with physical activity, insomnia, depression, and worry in pregnant women. Method: This was an observational cross sectional study, conducted among 256 healthy pregnant women using 5 questionnaires: WHOQOL-brief (WHO Quality of Life Questionnaire, brief version, ISI (Insomnia Severity Index), PSWQ (Penn State Worry Questionnaire), ZSRDS (Zung Self-Rating depression Scale), and Pregnancy Physical Activity Questionnaire (PPAQ). Results: There was a significant relationship between general QoL, insomnia, and worry with educational background, number of children, and occupation (P < 0.05). Depression had a significant relationship with occupation (P < 0.05). PA did not have a significant relationship with demographic information. However, insomnia had a significantly negative relationship with general QoL, general health, and psychological health (P < 0.05). The worry variable had also a significant negative relationship with general QoL, general health, and physiological health (P < 0.05). Depression had a significant negative relationship with general health, physical health, and psychological health (P < 0.05). There was no significant relationship between physical activities in pregnancy with QoL, depression, worry, and insomnia. Conclusion: Women need to be informed about the necessity of controlling and reducing insomnia, worry, and depression to have a higher QoL. PA declined during the second and third trimester of pregnancy. However, PA in pregnancy can positively impact general QoL.

Published
2020
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