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2. Multi-scale modeling of shock initiation of a pressed energetic material III: Effect of Arrhenius chemical kinetic rates on macro-scale shock sensitivity.

Author

Parepalli, P., Nguyen, Yen T., Sen, O., Hardin, D. B., Molek, C. D., Welle, E. J., and Udaykumar, H. S.

Subjects
MULTISCALE modeling, CHEMICAL kinetics, CHEMICAL models, PREDICTION models
Abstract

Multi-scale predictive models for the shock sensitivity of energetic materials connect energy localization ("hotspots") in the microstructure to macro-scale detonation phenomena. Calculations of hotspot ignition and growth rely on models for chemical reaction rates expressed in Arrhenius forms; these chemical kinetic models, therefore, are foundational to the construction of physics-based, simulation-derived meso-informed closure (reactive burn) models. However, even for commonly used energetic materials (e.g., HMX in this paper) there are a wide variety of reaction rate models available. These available reaction rate models produce reaction time scales that vary by several orders of magnitude. From a multi-scale modeling standpoint, it is important to determine which model best represents the reactive response of the material. In this paper, we examine three global Arrhenius-form rate models that span the range of reaction time scales, namely, the Tarver 3-equation, the Henson 1-equation, and the Menikoff 1-equation models. They are employed in a meso-informed ignition and growth model which allows for connecting meso-scale hotspot dynamics to macro-scale shock-to-detonation transition. The ability of the three reaction models to reproduce experimentally observed sensitivity is assessed by comparing the predicted criticality envelope (Walker–Wasley curve) with experimental data for pressed HMX Class V microstructures. The results provide a guideline for model developers on the plausible range of time-to-ignition that are produced by physically correct Arrhenius rate models for HMX. [ABSTRACT FROM AUTHOR]

Published
2024
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3. Structure-Property Linkage in Shocked Multi-Material Flows Using A Level-Set Based Eulerian Image-To-Computation Framework

Author

Roy, S, Rai, N, Sen, O, and Udaykumar, H. S.

Subjects
Physics - Computational Physics, Condensed Matter - Materials Science, Physics - Fluid Dynamics
Abstract

Morphology and dynamics at the meso-scale play crucial roles in the overall macro- or system-scale flow of heterogeneous materials. In a multi-scale framework, closure models upscale unresolved sub-grid (meso-scale) physics and therefore encapsulate structure-property (S-P) linkages to predict performance at the macro-scale. This work establishes a route to structure-property linkage, proceeding all the way from imaged micro-structures to flow computations in one unified level set-based framework. Level sets are used to: 1) Define embedded geometries via image segmentation; 2) Simulate the interaction of sharp immersed boundaries with the flow field, and 3) Calculate morphological metrics to quantify structure. Meso-scale dynamics are computed to calculate sub-grid properties, i.e. closure models for momentum and energy equations. The structure-property linkage is demonstrated for two types of multi-material flows: interaction of shocks with a cloud of particles and reactive meso-mechanics of pressed energetic materials. We also present an approach to connect local morphological characteristics in a microstructure containing topologically complex features with the shock response of imaged samples of such materials. This paves the way for using geometric machine learning techniques to associate imaged morphologies with their properties.

Published
2019
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4. Modeling meso-scale energy localization in shocked HMX, Part II: training machine-learned surrogate models for void shape and void-void interaction effects

Author

Roy, S., Rai, N. K., Sen, O., Hardin, D. B., Diggs, A. S., and Udaykumar, H. S.

Subjects
Physics - Computational Physics, Condensed Matter - Mesoscale and Nanoscale Physics, Physics - Applied Physics
Abstract

Surrogate models for hotspot ignition and growth rates were presented in Part I, where the hotspots were formed by the collapse of single cylindrical voids. Such isolated cylindrical voids are idealizations of the void morphology in real meso-structures. This paper therefore investigates the effect of non-cylindrical void shapes and void-void interactions on hotspot ignition and growth. Surrogate models capturing these effects are constructed using a Bayesian Kriging approach. The training data for machine learning the surrogates are derived from reactive void collapse simulations spanning the parameter space of void aspect ratio (AR), void orientation ($\theta$), and void fraction ($\phi$). The resulting surrogate models portray strong dependence of the ignition and growth rates on void aspect ratio and orientation, particularly when they are oriented at acute angles with respect to the imposed shock. The surrogate models for void interaction effects show significant changes in hotspot ignition and growth rates as the void fraction increases. The paper elucidates the physics of hotspot evolution in void fields due to the creation and interaction of multiple hotspots. The results from this work will be useful not only for constructing meso-informed macro-scale models of HMX, but also for understanding the physics of void-void interactions and sensitivity due to void shape and orientation., Comment: Submitted in Shockwaves

Published
2019
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5. Scaling Law for Criticality Conditions in Heterogeneous Energetic Materials under Shock Loading

Author

Nassar, A., Rai, N. K., Sen, O., and Udaykumar, H. S.

Subjects
Physics - Applied Physics, Physics - Computational Physics
Abstract

Initiation in heterogeneous energetic material (HEM) subjected to shock loading occurs due to the formation of hot spots. The criticality of the hot spots governs the initiation and sensitivity of HEMs. In porous energetic materials, collapse of pores under impact leads to the formation of hot spots. Depending on the size and strength of the hot spots chemical reaction can initiate. The criticality of the hot spots is dependent on the imposed shock load, void morphology and the type of energetic material. This work evaluates the relative importance of material constitutive and reactive properties on the criticality condition of spots. Using a scaling-based approach, the criticality criterion for cylindrical voids as a function of shock pressure, Ps and void diameter, Dvoid is obtained for two different energetic material HMX and TATB. It is shown that the criticality of different energetic materials is significantly dependent on their reactive properties.

Published
2018

6. NMR detection of dynamical processes in antiferroelectric nanoclusters during the order-disorder transition in NH4H2AsO4

Author

Fu, R., Gunaydin-Sen, O., Chiorescu, I., and Dalal, N. S.

Subjects
Condensed Matter - Mesoscale and Nanoscale Physics
Abstract

We study the dynamics of inorganic antiferroelectric nanoclusters formed during an order-disorder transition and demonstrate the coexistence of the two phases in a region of 2-3 K around the transition temperature TN~215 K. Single crystals of NH4H2AsO4, a model hydrogen-bonded compound, show an antiferroelectric-paraelectric transition studied by means of highly sensitive magic angle spinning 15N NMR at 21.1 T. The phase co-existence is demonstrated by a double-peak structure of the chemical shift. Two-dimensional chemical exchange spectroscopy and spin-lattice relaxation time (T1) measurements show that the clusters are dynamic with sizes ~50 nm and lifetimes approaching seconds as T->TN. Their occupancy increases rapidly to fill the crystal volume below $T_N$. This study provides evidence for the commonality of the phase transitions in systems with electric properties and provides an improved spectroscopic method for such studies.

Published
2015
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13. 30-day morbidity and mortality of sleeve gastrectomy, Roux-en-Y gastric bypass and one anastomosis gastric bypass: a propensity score-matched analysis of the GENEVA data

Author

Singhal R., Cardoso V. R., Wiggins T., Super J., Ludwig C., Gkoutos G. V., Mahawar K., Pedziwiatr M., Major P., Zarzycki P., Pantelis A., Lapatsanis D. P., Stravodimos G., Matthys C., Focquet M., Vleeschouwers W., Spaventa A. G., Zerrweck C., Vitiello A., Berardi G., Musella M., Sanchez-Meza A., Cantu F. J., Mora F., Cantu M. A., Katakwar A., Reddy D. N., Elmaleh H., Hassan M., Elghandour A., Elbanna M., Osman A., Khan A., layani L., Kiran N., Velikorechin A., Solovyeva M., Melali H., Shahabi S., Agrawal A., Shrivastava A., Sharma A., Narwaria B., Narwaria M., Raziel A., Sakran N., Susmallian S., Karagoz L., Akbaba M., Piskin S. Z., Balta A. Z., Senol Z., Manno E., Iovino M. G., Qassem M., Arana-Garza S., Povoas H. P., Vilas-Boas M. L., Naumann D., Li A., Ammori B. J., Balamoun H., Salman M., Nasta A. M., Goel R., Sanchez-Aguilar H., Herrera M. F., Abou-mrad A., Cloix L., Mazzini G. S., Kristem L., Lazaro A., Campos J., Bernardo J., Gonzalez J., Trindade C., Viveiros O., Ribeiro R., Goitein D., Hazzan D., Segev L., Beck T., Reyes H., Monterrubio J., Garcia P., Benois M., Kassir R., Contine A., Elshafei M., Aktas S., Weiner S., Heidsieck T., Level L., Pinango S., Ortega P. M., Moncada R., Valenti V., Vlahovic I., Boras Z., Liagre A., Martini F., Juglard G., Motwani M., Saggu S. S., Momani H. A., Lopez L. A. A., Cortez M. A. C., Zavala R. A., D'Haese RN C., Kempeneers I., Himpens J., Lazzati A., Paolino L., Bathaei S., Bedirli A., Yavuz A., Buyukkasap C., Ozaydin S., Kwiatkowski A., Bartosiak K., Waledziak M., Santonicola A., Angrisani L., Iovino P., Palma R., Iossa A., Boru C. E., De Angelis F., Silecchia G., Hussain A., Balchandra S., Coltell I. B., Perez J. L., Bohra A., Awan A. K., Madhok B., Leeder P. C., Awad S., Al-Khyatt W., Shoma A., Elghadban H., Ghareeb S., Mathews B., Kurian M., Larentzakis A., Vrakopoulou G. Z., Albanopoulos K., Bozdag A., Lale A., Kirkil C., Dincer M., Bashir A., Haddad A., Hijleh L. A., Zilberstein B., de Marchi D. D., Souza W. P., Broden C. M., Gislason H., Shah K., Ambrosi A., Pavone G., Tartaglia N., Kona S. L. K., Kalyan K., Perez C. E. G., Botero M. A. F., Covic A., Timofte D., Maxim M., Faraj D., Tseng L., Liem R., Oren G., Dilektasli E., Yalcin I., AlMukhtar H., Hadad M. A., Mohan R., Arora N., Bedi D., Rives-Lange C., Chevallier J. -M., Poghosyan T., Sebbag H., Zinai L., Khaldi S., Mauchien C., Mazza D., Dinescu G., Rea B., Perez-Galaz F., Zavala L., Besa A., Curell A., Balibrea J. M., Vaz C., Galindo L., Silva N., Caballero J. L. E., Sebastian S. O., Marchesini J. C. D., da Fonseca Pereira R. A., Sobottka W. H., Fiolo F. E., Turchi M., Coelho A. C. J., Zacaron A. L., Barbosa A., Quinino R., Menaldi G., Paleari N., Martinez-Duartez P., de Esparza G. M. A. R., Esteban V. S., Torres A., Garcia-Galocha J. L., Josa M., Pacheco-Garcia J. M., Mayo-Ossorio M. A., Chowbey P., Soni V., de Vasconcelos Cunha H. A., Castilho M. V., Ferreira R. M. A., Barreiro T. A., Charalabopoulos A., Sdralis E., Davakis S., Bomans B., Dapri G., Van Belle K., Takieddine M., Vaneukem P., Karaca E. S. A., Karaca F. C., Sumer A., Peksen C., Savas O. A., Chousleb E., Elmokayed F., Fakhereldin I., Aboshanab H. M., Swelium T., Gudal A., Gamloo L., Ugale A., Ugale S., Boeker C., Reetz C., Hakami I. A., Mall J., Alexandrou A., Baili E., Bodnar Z., Maleckas A., Gudaityte R., Guldogan C. E., Gundogdu E., Ozmen M. M., Thakkar D., Dukkipati N., Shah P. S., Shah S. S., Adil M. T., Jambulingam P., Mamidanna R., Whitelaw D., Jain V., Veetil D. K., Wadhawan R., Torres M., Tinoco T., Leclercq W., Romeijn M., van de Pas K., Alkhazraji A. K., Taha S. A., Ustun M., Yigit T., Inam A., Burhanulhaq M., Pazouki A., Eghbali F., Kermansaravi M., Jazi A. H. D., Mahmoudieh M., Mogharehabed N., Tsiotos G., Stamou K., Rodriguez F. J. B., Navarro M. A. R., Torres O. M., Martinez S. L., Tamez E. R. M., Cornejo G. A. M., Flores J. E. G., Mohammed D. A., Elfawal M. H., Shabbir A., Guowei K., So J. B., Kaplan E. T., Kaplan M., Kaplan T., Pham D. T., Rana G., Kappus M., Gadani R., Kahitan M., Pokharel K., Osborne A., Pournaras D., Hewes J., Napolitano E., Chiappetta S., Bottino V., Dorado E., Schoettler A., Gaertner D., Fedtke K., Aguilar-Espinosa F., Aceves-Lozano S., Balani A., Nagliati C., Pennisi D., Rizzi A., Frattini F., Foschi D., Benuzzi L., Parikh C., Shah H., Pinotti E., Montuori M., Borrelli V., Dargent J., Copaescu C. A., Hutopila I., Smeu B., Witteman B., Hazebroek E., Deden L., Heusschen L., Okkema S., Aufenacker T., den Hengst W., Vening W., van der Burgh Y., Ghazal A., Ibrahim H., Niazi M., Alkhaffaf B., Altarawni M., Cesana G. C., Anselmino M., Uccelli M., Olmi S., Stier C., Akmanlar T., Sonnenberg T., Schieferbein U., Marcolini A., Awruch D., Vicentin M., de Souza Bastos E. L., Gregorio S. A., Ahuja A., Mittal T., Bolckmans R., Baratte C., Wisnewsky J. A., Genser L., Chong L., Taylor L., Ward S., Hi M. W., Heneghan H., Fearon N., Plamper A., Rheinwalt K., Geoghegan J., Ng K. C., Kaseja K., Kotowski M., Samarkandy T. A., Leyva-Alvizo A., Corzo-Culebro L., Wang C., Yang W., Dong Z., Riera M., Jain R., Hamed H., Said M., Zarzar K., Garcia M., Turkcapar A. G., Sen O., Baldini E., Conti L., Wietzycoski C., Lopes E., Pintar T., Salobir J., Aydin C., Atici S. D., Ergin A., Ciyiltepe H., Bozkurt M. A., Kizilkaya M. C., Onalan N. B. D., Zuber M. N. B. A., Wong W. J., Garcia A., Vidal L., Beisani M., Pasquier J., Vilallonga R., Sharma S., Parmar C., Lee L., Sufi P., Sinan H., Saydam M., Singhal, R., Cardoso, V. R., Wiggins, T., Super, J., Ludwig, C., Gkoutos, G. V., Mahawar, K., Pedziwiatr, M., Major, P., Zarzycki, P., Pantelis, A., Lapatsanis, D. P., Stravodimos, G., Matthys, C., Focquet, M., Vleeschouwers, W., Spaventa, A. G., Zerrweck, C., Vitiello, A., Berardi, G., Musella, M., Sanchez-Meza, A., Cantu, F. J., Mora, F., Cantu, M. A., Katakwar, A., Reddy, D. N., Elmaleh, H., Hassan, M., Elghandour, A., Elbanna, M., Osman, A., Khan, A., Layani, L., Kiran, N., Velikorechin, A., Solovyeva, M., Melali, H., Shahabi, S., Agrawal, A., Shrivastava, A., Sharma, A., Narwaria, B., Narwaria, M., Raziel, A., Sakran, N., Susmallian, S., Karagoz, L., Akbaba, M., Piskin, S. Z., Balta, A. Z., Senol, Z., Manno, E., Iovino, M. G., Qassem, M., Arana-Garza, S., Povoas, H. P., Vilas-Boas, M. L., Naumann, D., Li, A., Ammori, B. J., Balamoun, H., Salman, M., Nasta, A. M., Goel, R., Sanchez-Aguilar, H., Herrera, M. F., Abou-mrad, A., Cloix, L., Mazzini, G. S., Kristem, L., Lazaro, A., Campos, J., Bernardo, J., Gonzalez, J., Trindade, C., Viveiros, O., Ribeiro, R., Goitein, D., Hazzan, D., Segev, L., Beck, T., Reyes, H., Monterrubio, J., Garcia, P., Benois, M., Kassir, R., Contine, A., Elshafei, M., Aktas, S., Weiner, S., Heidsieck, T., Level, L., Pinango, S., Ortega, P. M., Moncada, R., Valenti, V., Vlahovic, I., Boras, Z., Liagre, A., Martini, F., Juglard, G., Motwani, M., Saggu, S. S., Momani, H. A., Lopez, L. A. A., Cortez, M. A. C., Zavala, R. A., D'Haese RN, C., Kempeneers, I., Himpens, J., Lazzati, A., Paolino, L., Bathaei, S., Bedirli, A., Yavuz, A., Buyukkasap, C., Ozaydin, S., Kwiatkowski, A., Bartosiak, K., Waledziak, M., Santonicola, A., Angrisani, L., Iovino, P., Palma, R., Iossa, A., Boru, C. E., De Angelis, F., Silecchia, G., Hussain, A., Balchandra, S., Coltell, I. B., Perez, J. L., Bohra, A., Awan, A. K., Madhok, B., Leeder, P. C., Awad, S., Al-Khyatt, W., Shoma, A., Elghadban, H., Ghareeb, S., Mathews, B., Kurian, M., Larentzakis, A., Vrakopoulou, G. Z., Albanopoulos, K., Bozdag, A., Lale, A., Kirkil, C., Dincer, M., Bashir, A., Haddad, A., Hijleh, L. A., Zilberstein, B., de Marchi, D. D., Souza, W. P., Broden, C. M., Gislason, H., Shah, K., Ambrosi, A., Pavone, G., Tartaglia, N., Kona, S. L. K., Kalyan, K., Perez, C. E. G., Botero, M. A. F., Covic, A., Timofte, D., Maxim, M., Faraj, D., Tseng, L., Liem, R., Oren, G., Dilektasli, E., Yalcin, I., Almukhtar, H., Hadad, M. A., Mohan, R., Arora, N., Bedi, D., Rives-Lange, C., Chevallier, J. -M., Poghosyan, T., Sebbag, H., Zinai, L., Khaldi, S., Mauchien, C., Mazza, D., Dinescu, G., Rea, B., Perez-Galaz, F., Zavala, L., Besa, A., Curell, A., Balibrea, J. M., Vaz, C., Galindo, L., Silva, N., Caballero, J. L. E., Sebastian, S. O., Marchesini, J. C. D., da Fonseca Pereira, R. A., Sobottka, W. H., Fiolo, F. E., Turchi, M., Coelho, A. C. J., Zacaron, A. L., Barbosa, A., Quinino, R., Menaldi, G., Paleari, N., Martinez-Duartez, P., de Esparza, G. M. A. R., Esteban, V. S., Torres, A., Garcia-Galocha, J. L., Josa, M., Pacheco-Garcia, J. M., Mayo-Ossorio, M. A., Chowbey, P., Soni, V., de Vasconcelos Cunha, H. A., Castilho, M. V., Ferreira, R. M. A., Barreiro, T. A., Charalabopoulos, A., Sdralis, E., Davakis, S., Bomans, B., Dapri, G., Van Belle, K., Takieddine, M., Vaneukem, P., Karaca, E. S. A., Karaca, F. C., Sumer, A., Peksen, C., Savas, O. A., Chousleb, E., Elmokayed, F., Fakhereldin, I., Aboshanab, H. M., Swelium, T., Gudal, A., Gamloo, L., Ugale, A., Ugale, S., Boeker, C., Reetz, C., Hakami, I. A., Mall, J., Alexandrou, A., Baili, E., Bodnar, Z., Maleckas, A., Gudaityte, R., Guldogan, C. E., Gundogdu, E., Ozmen, M. M., Thakkar, D., Dukkipati, N., Shah, P. S., Shah, S. S., Adil, M. T., Jambulingam, P., Mamidanna, R., Whitelaw, D., Jain, V., Veetil, D. K., Wadhawan, R., Torres, M., Tinoco, T., Leclercq, W., Romeijn, M., van de Pas, K., Alkhazraji, A. K., Taha, S. A., Ustun, M., Yigit, T., Inam, A., Burhanulhaq, M., Pazouki, A., Eghbali, F., Kermansaravi, M., Jazi, A. H. D., Mahmoudieh, M., Mogharehabed, N., Tsiotos, G., Stamou, K., Rodriguez, F. J. B., Navarro, M. A. R., Torres, O. M., Martinez, S. L., Tamez, E. R. M., Cornejo, G. A. M., Flores, J. E. G., Mohammed, D. A., Elfawal, M. H., Shabbir, A., Guowei, K., So, J. B., Kaplan, E. T., Kaplan, M., Kaplan, T., Pham, D. T., Rana, G., Kappus, M., Gadani, R., Kahitan, M., Pokharel, K., Osborne, A., Pournaras, D., Hewes, J., Napolitano, E., Chiappetta, S., Bottino, V., Dorado, E., Schoettler, A., Gaertner, D., Fedtke, K., Aguilar-Espinosa, F., Aceves-Lozano, S., Balani, A., Nagliati, C., Pennisi, D., Rizzi, A., Frattini, F., Foschi, D., Benuzzi, L., Parikh, C., Shah, H., Pinotti, E., Montuori, M., Borrelli, V., Dargent, J., Copaescu, C. A., Hutopila, I., Smeu, B., Witteman, B., Hazebroek, E., Deden, L., Heusschen, L., Okkema, S., Aufenacker, T., den Hengst, W., Vening, W., van der Burgh, Y., Ghazal, A., Ibrahim, H., Niazi, M., Alkhaffaf, B., Altarawni, M., Cesana, G. C., Anselmino, M., Uccelli, M., Olmi, S., Stier, C., Akmanlar, T., Sonnenberg, T., Schieferbein, U., Marcolini, A., Awruch, D., Vicentin, M., de Souza Bastos, E. L., Gregorio, S. A., Ahuja, A., Mittal, T., Bolckmans, R., Baratte, C., Wisnewsky, J. A., Genser, L., Chong, L., Taylor, L., Ward, S., Hi, M. W., Heneghan, H., Fearon, N., Plamper, A., Rheinwalt, K., Geoghegan, J., Ng, K. C., Kaseja, K., Kotowski, M., Samarkandy, T. A., Leyva-Alvizo, A., Corzo-Culebro, L., Wang, C., Yang, W., Dong, Z., Riera, M., Jain, R., Hamed, H., Said, M., Zarzar, K., Garcia, M., Turkcapar, A. G., Sen, O., Baldini, E., Conti, L., Wietzycoski, C., Lopes, E., Pintar, T., Salobir, J., Aydin, C., Atici, S. D., Ergin, A., Ciyiltepe, H., Bozkurt, M. A., Kizilkaya, M. C., Onalan, N. B. D., Zuber, M. N. B. A., Wong, W. J., Garcia, A., Vidal, L., Beisani, M., Pasquier, J., Vilallonga, R., Sharma, S., Parmar, C., Lee, L., Sufi, P., Sinan, H., Saydam, M., İstinye Üniversitesi, Tıp Fakültesi, Cerrahi Tıp Bilimleri Bölümü, Sumer, Aziz, Peksen, Caghan, and Savas, Osman Anil

Subjects
Nutrition and Dietetics, Endocrinology, Diabetes and Metabolism, Gastric Bypass, Medicine (miscellaneous), nutritional and metabolic diseases, COVID-19, Gastrectomy, Humans, Morbidity, Propensity Score, Retrospective Studies, Treatment Outcome, Diabetes Mellitus, Type 2, Obesity, Morbid, Article, Diabetes Mellitus, Obesity, Morbid, Type 2
Abstract

Background There is a paucity of data comparing 30-day morbidity and mortality of sleeve gastrectomy (SG), Roux-en-Y gastric bypass (RYGB), and one anastomosis gastric bypass (OAGB). This study aimed to compare the 30-day safety of SG, RYGB, and OAGB in propensity score-matched cohorts. Materials and methods This analysis utilised data collected from the GENEVA study which was a multicentre observational cohort study of bariatric and metabolic surgery (BMS) in 185 centres across 42 countries between 01/05/2022 and 31/10/2020 during the Coronavirus Disease-2019 (COVID-19) pandemic. 30-day complications were categorised according to the Clavien–Dindo classification. Patients receiving SG, RYGB, or OAGB were propensity-matched according to baseline characteristics and 30-day complications were compared between groups. Results In total, 6770 patients (SG 3983; OAGB 702; RYGB 2085) were included in this analysis. Prior to matching, RYGB was associated with highest 30-day complication rate (SG 5.8%; OAGB 7.5%; RYGB 8.0% (p = 0.006)). On multivariate regression modelling, Insulin-dependent type 2 diabetes mellitus and hypercholesterolaemia were associated with increased 30-day complications. Being a non-smoker was associated with reduced complication rates. When compared to SG as a reference category, RYGB, but not OAGB, was associated with an increased rate of 30-day complications. A total of 702 pairs of SG and OAGB were propensity score-matched. The complication rate in the SG group was 7.3% (n = 51) as compared to 7.5% (n = 53) in the OAGB group (p = 0.68). Similarly, 2085 pairs of SG and RYGB were propensity score-matched. The complication rate in the SG group was 6.1% (n = 127) as compared to 7.9% (n = 166) in the RYGB group (p = 0.09). And, 702 pairs of OAGB and RYGB were matched. The complication rate in both groups was the same at 7.5 % (n = 53; p = 0.07). Conclusions This global study found no significant difference in the 30-day morbidity and mortality of SG, RYGB, and OAGB in propensity score-matched cohorts.

Published
2021

17. 30-Day morbidity and mortality of bariatric metabolic surgery in adolescence during the COVID-19 pandemic – The GENEVA study

Author

Singhal R., Wiggins T., Super J., Alqahtani A., Nadler E. P., Ludwig C., Tahrani A., Mahawar K., Pedziwiatr M., Major P., Zarzycki P., Pantelis A., Lapatsanis D. P., Stravodimos G., Matthys C., Focquet M., Vleeschouwers W., Spaventa A. G., Zerrweck C., Vitiello A., Berardi G., Musella M., Sanchez-Meza A., Cantu F. J., Mora F., Cantu M. A., Katakwar A., Reddy D. N., Elmaleh H., Hassan M., Elghandour A., Elbanna M., Osman A., Khan A., Layani L., Kiran N., Velikorechin A., Solovyeva M., Melali H., Shahabi S., Agrawal A., Shrivastava A., Sharma A., Narwaria B., Narwaria M., Raziel A., Sakran N., Susmallian S., Karagoz L., Akbaba M., Piskin S. Z., Ziya A., Senol Z., Manno E., Iovino M. G., Qassem M., Arana-Garza S., Povoas H. P., Vilas-Boas M. L., Naumann D., Li A., Ammori B. J., Balamoun H., Salman M., Nasta A. M., Goel R., Sanchez-Aguilar H., Herrera M. F., Abou-Mrad A., Cloix L., Mazzini G. S., Kristem L., Lazaro A., Campos J., Bernardo J., Gonzalez J., Trindade C., Viveiros O., Ribeiro R., Goitein D., Hazzan D., Segev L., Beck T., Reyes H., Monterrubio J., Garcia P., Benois M., Kassir R., Contine A., Elshafei M., Aktas S., Weiner S., Heidsieck T., Level L., Pinango S., Ortega P. M., Moncada R., Valenti V., Vlahovic I., Boras Z., Liagre A., Martini F., Juglard G., Motwani M., Saggu S. S., Al Momani H., Lopez L. A. A., Cortez M. A. C., Zavala R. A., D'Haese C., Kempeneers I., Himpens J., Lazzati A., Paolino L., Bathaei S., Bedirli A., Yavuz A., Buyukkasap C., Ozaydin S., Kwiatkowski A., Bartosiak K., Waledziak M., Santonicola A., Angrisani L., Iovino P., Palma R., Iossa A., Boru C. E., De Angelis F., Silecchia G., Hussain A., Balchandra S., Coltell I. B., Perez J. L., Bohra A., Awan A. K., Madhok B., Leeder P. C., Awad S., Al-Khyatt W., Shoma A., Elghadban H., Ghareeb S., Mathews B., Kurian M., Larentzakis A., Vrakopoulou G. Z., Albanopoulos K., Bozdag A., Lale A., Kirkil C., Dincer M., Bashir A., Haddad A., Hijleh L. A., Zilberstein B., de Marchi D. D., Souza W. P., Broden C. M., Gislason H., Shah K., Ambrosi A., Pavone G., Tartaglia N., Kona S. L. K., Kalyan K., Perez C. E. G., Botero M. A. F., Covic A., Timofte D., Maxim M., Faraj D., Tseng L., Liem R., Oren G., Dilektasli E., Yalcin I., AlMukhtar H., Al Hadad M., Mohan R., Arora N., Bedi D., Rives-Lange C., Chevallier J. -M., Poghosyan T., Sebbag H., Zinai L., Khaldi S., Mauchien C., Mazza D., Dinescu G., Rea B., Perez-Galaz F., Zavala L., Besa A., Curell A., Balibrea J. M., Vaz C., Galindo L., Silva N., Caballero J. L. E., Sebastian S. O., Marchesini J. C. D., da Fonseca Pereira R. A., Sobottka W. H., Fiolo F. E., Turchi M., Coelho A. C. J., Zacaron A. L., Barbosa A., Quinino R., Menaldi G., Paleari N., Martinez-Duartez P., Aragon Ramirez de Esparza D. G. M., Esteban V. S., Torres A., Garcia-Galocha J. L., Josa M. I., Pacheco-Garcia J. M., Mayo-Ossorio M. A., Chowbey P., Soni V., de Vasconcelos Cunha H. A., Castilho M. V., Ferreira R. M. A., Barreiro T. A., Charalabopoulos A., Sdralis E., Davakis S., Bomans B., Dapri G., Van Belle K., MazenTakieddine, Vaneukem P., Karaca E. S. A., Karaca F. C., Sumer A., Peksen C., Savas O. A., Chousleb E., Elmokayed F., Fakhereldin I., Aboshanab H. M., Swelium T., Gudal A., Gamloo L., Ugale A., Ugale S., Boeker C., Reetz C., Hakami I. A., Mall J., Alexandrou A., Baili E., Bodnar Z., Maleckas A., Gudaityte R., Guldogan C. E., Gundogdu E., Ozmen M. M., Thakkar D., Dukkipati N., Shah P. S., Shah S. S., Adil M. T., Jambulingam P., Mamidanna R., Whitelaw D., Jain V., Veetil D. K., Wadhawan R., Torres M., Tinoco T., Leclercq W., Romeijn M., van de Pas K., Alkhazraji A. K., Taha S. A., Ustun M., Yigit T., Inam A., Burhanulhaq M., Pazouki A., Eghbali F., Kermansaravi M., Jazi A. H. D., Mahmoudieh M., Mogharehabed N., Tsiotos G., Stamou K., Barrera Rodriguez F. J., Rojas Navarro M. A., Torres O. M. O., Martinez S. L., Tamez E. R. M., Millan Cornejo G. A., Flores J. E. G., Mohammed D. A., Elfawal M. H., Shabbir A., Guowei K., So J. B. Y., Kaplan E. T., Kaplan M., Kaplan T., Pham D. T., Rana G., Kappus M., Gadani R., Kahitan M., Pokharel K., Osborne A., Pournaras D., Hewes J., Napolitano E., Chiappetta S., Bottino V., Dorado E., Schoettler A., Gaertner D., Fedtke K., Aguilar-Espinosa F., Aceves-Lozano S., Balani A., Nagliati C., Pennisi D., Rizzi A., Frattini F., Foschi D., Benuzzi L., Parikh C. H. I. R. A. G., Shah H. A. R. S. H. I. L., Pinotti E., Montuori M., Borrelli V., Dargent J., Copaescu C. A., Hutopila I., Smeu B., Witteman B., Hazebroek E., Deden L., Heusschen L., Okkema S., Aufenacker T., den Hengst W., Vening W., van der Burgh Y., Ghazal A., Ibrahim H., Niazi M., Alkhaffaf B., Altarawni M., Cesana G. C., Anselmino M., Uccelli M., Olmi S., Stier C., Akmanlar T., Sonnenberg T., Schieferbein U., Marcolini A., Awruch D., Vicentin M., de Souza Bastos E. L., Gregorio S. A., Ahuja A., Mittal T., Bolckmans R., Baratte C., Wisnewsky J. A., Genser L., Chong L., Taylor L., Ward S., Hi M. W., Heneghan H., Fearon N., Plamper A., Rheinwalt K., Geoghegan J., Ng K. C., Kaseja K., Kotowski M., Samarkandy T. A., Leyva-Alvizo A., Corzo-Culebro L., Wang C., Yang W., Dong Z., Riera M., Jain R., Hamed H., Said M., Zarzar K., Garcia M., Turkcapar A. G., Sen O., Baldini E., Conti L., Wietzycoski C., Lopes E., Pintar T., Salobir J., Aydin C., Atici S. D., Ergin A., Ciyiltepe H., Bozkurt M. A., Kizilkaya M. C., Onalan N. B. D., Zuber M. N. B. A., Wong W. J., Garcia A., Vidal L., Beisani M., Pasquier J., Vilallonga R., Sharma S., Parmar C., Lee L., Sufi P., Sinan H., Saydam M., Singhal, R., Wiggins, T., Super, J., Alqahtani, A., Nadler, E. P., Ludwig, C., Tahrani, A., Mahawar, K., Pedziwiatr, M., Major, P., Zarzycki, P., Pantelis, A., Lapatsanis, D. P., Stravodimos, G., Matthys, C., Focquet, M., Vleeschouwers, W., Spaventa, A. G., Zerrweck, C., Vitiello, A., Berardi, G., Musella, M., Sanchez-Meza, A., Cantu, F. J., Mora, F., Cantu, M. A., Katakwar, A., Reddy, D. N., Elmaleh, H., Hassan, M., Elghandour, A., Elbanna, M., Osman, A., Khan, A., Layani, L., Kiran, N., Velikorechin, A., Solovyeva, M., Melali, H., Shahabi, S., Agrawal, A., Shrivastava, A., Sharma, A., Narwaria, B., Narwaria, M., Raziel, A., Sakran, N., Susmallian, S., Karagoz, L., Akbaba, M., Piskin, S. Z., Ziya, A., Senol, Z., Manno, E., Iovino, M. G., Qassem, M., Arana-Garza, S., Povoas, H. P., Vilas-Boas, M. L., Naumann, D., Li, A., Ammori, B. J., Balamoun, H., Salman, M., Nasta, A. M., Goel, R., Sanchez-Aguilar, H., Herrera, M. F., Abou-Mrad, A., Cloix, L., Mazzini, G. S., Kristem, L., Lazaro, A., Campos, J., Bernardo, J., Gonzalez, J., Trindade, C., Viveiros, O., Ribeiro, R., Goitein, D., Hazzan, D., Segev, L., Beck, T., Reyes, H., Monterrubio, J., Garcia, P., Benois, M., Kassir, R., Contine, A., Elshafei, M., Aktas, S., Weiner, S., Heidsieck, T., Level, L., Pinango, S., Ortega, P. M., Moncada, R., Valenti, V., Vlahovic, I., Boras, Z., Liagre, A., Martini, F., Juglard, G., Motwani, M., Saggu, S. S., Al Momani, H., Lopez, L. A. A., Cortez, M. A. C., Zavala, R. A., D'Haese, C., Kempeneers, I., Himpens, J., Lazzati, A., Paolino, L., Bathaei, S., Bedirli, A., Yavuz, A., Buyukkasap, C., Ozaydin, S., Kwiatkowski, A., Bartosiak, K., Waledziak, M., Santonicola, A., Angrisani, L., Iovino, P., Palma, R., Iossa, A., Boru, C. E., De Angelis, F., Silecchia, G., Hussain, A., Balchandra, S., Coltell, I. B., Perez, J. L., Bohra, A., Awan, A. K., Madhok, B., Leeder, P. C., Awad, S., Al-Khyatt, W., Shoma, A., Elghadban, H., Ghareeb, S., Mathews, B., Kurian, M., Larentzakis, A., Vrakopoulou, G. Z., Albanopoulos, K., Bozdag, A., Lale, A., Kirkil, C., Dincer, M., Bashir, A., Haddad, A., Hijleh, L. A., Zilberstein, B., de Marchi, D. D., Souza, W. P., Broden, C. M., Gislason, H., Shah, K., Ambrosi, A., Pavone, G., Tartaglia, N., Kona, S. L. K., Kalyan, K., Perez, C. E. G., Botero, M. A. F., Covic, A., Timofte, D., Maxim, M., Faraj, D., Tseng, L., Liem, R., Oren, G., Dilektasli, E., Yalcin, I., Almukhtar, H., Al Hadad, M., Mohan, R., Arora, N., Bedi, D., Rives-Lange, C., Chevallier, J. -M., Poghosyan, T., Sebbag, H., Zinai, L., Khaldi, S., Mauchien, C., Mazza, D., Dinescu, G., Rea, B., Perez-Galaz, F., Zavala, L., Besa, A., Curell, A., Balibrea, J. M., Vaz, C., Galindo, L., Silva, N., Caballero, J. L. E., Sebastian, S. O., Marchesini, J. C. D., da Fonseca Pereira, R. A., Sobottka, W. H., Fiolo, F. E., Turchi, M., Coelho, A. C. J., Zacaron, A. L., Barbosa, A., Quinino, R., Menaldi, G., Paleari, N., Martinez-Duartez, P., Aragon Ramirez de Esparza, D. G. M., Esteban, V. S., Torres, A., Garcia-Galocha, J. L., Josa, M. I., Pacheco-Garcia, J. M., Mayo-Ossorio, M. A., Chowbey, P., Soni, V., de Vasconcelos Cunha, H. A., Castilho, M. V., Ferreira, R. M. A., Barreiro, T. A., Charalabopoulos, A., Sdralis, E., Davakis, S., Bomans, B., Dapri, G., Van Belle, K., Mazentakieddine, Vaneukem, P., Karaca, E. S. A., Karaca, F. C., Sumer, A., Peksen, C., Savas, O. A., Chousleb, E., Elmokayed, F., Fakhereldin, I., Aboshanab, H. M., Swelium, T., Gudal, A., Gamloo, L., Ugale, A., Ugale, S., Boeker, C., Reetz, C., Hakami, I. A., Mall, J., Alexandrou, A., Baili, E., Bodnar, Z., Maleckas, A., Gudaityte, R., Guldogan, C. E., Gundogdu, E., Ozmen, M. M., Thakkar, D., Dukkipati, N., Shah, P. S., Shah, S. S., Adil, M. T., Jambulingam, P., Mamidanna, R., Whitelaw, D., Jain, V., Veetil, D. K., Wadhawan, R., Torres, M., Tinoco, T., Leclercq, W., Romeijn, M., van de Pas, K., Alkhazraji, A. K., Taha, S. A., Ustun, M., Yigit, T., Inam, A., Burhanulhaq, M., Pazouki, A., Eghbali, F., Kermansaravi, M., Jazi, A. H. D., Mahmoudieh, M., Mogharehabed, N., Tsiotos, G., Stamou, K., Barrera Rodriguez, F. J., Rojas Navarro, M. A., Torres, O. M. O., Martinez, S. L., Tamez, E. R. M., Millan Cornejo, G. A., Flores, J. E. G., Mohammed, D. A., Elfawal, M. H., Shabbir, A., Guowei, K., So, J. B. Y., Kaplan, E. T., Kaplan, M., Kaplan, T., Pham, D. T., Rana, G., Kappus, M., Gadani, R., Kahitan, M., Pokharel, K., Osborne, A., Pournaras, D., Hewes, J., Napolitano, E., Chiappetta, S., Bottino, V., Dorado, E., Schoettler, A., Gaertner, D., Fedtke, K., Aguilar-Espinosa, F., Aceves-Lozano, S., Balani, A., Nagliati, C., Pennisi, D., Rizzi, A., Frattini, F., Foschi, D., Benuzzi, L., Parikh, C. H. I. R. A. G., Shah, H. A. R. S. H. I. L., Pinotti, E., Montuori, M., Borrelli, V., Dargent, J., Copaescu, C. A., Hutopila, I., Smeu, B., Witteman, B., Hazebroek, E., Deden, L., Heusschen, L., Okkema, S., Aufenacker, T., den Hengst, W., Vening, W., van der Burgh, Y., Ghazal, A., Ibrahim, H., Niazi, M., Alkhaffaf, B., Altarawni, M., Cesana, G. C., Anselmino, M., Uccelli, M., Olmi, S., Stier, C., Akmanlar, T., Sonnenberg, T., Schieferbein, U., Marcolini, A., Awruch, D., Vicentin, M., de Souza Bastos, E. L., Gregorio, S. A., Ahuja, A., Mittal, T., Bolckmans, R., Baratte, C., Wisnewsky, J. A., Genser, L., Chong, L., Taylor, L., Ward, S., Hi, M. W., Heneghan, H., Fearon, N., Plamper, A., Rheinwalt, K., Geoghegan, J., Ng, K. C., Kaseja, K., Kotowski, M., Samarkandy, T. A., Leyva-Alvizo, A., Corzo-Culebro, L., Wang, C., Yang, W., Dong, Z., Riera, M., Jain, R., Hamed, H., Said, M., Zarzar, K., Garcia, M., Turkcapar, A. G., Sen, O., Baldini, E., Conti, L., Wietzycoski, C., Lopes, E., Pintar, T., Salobir, J., Aydin, C., Atici, S. D., Ergin, A., Ciyiltepe, H., Bozkurt, M. A., Kizilkaya, M. C., Onalan, N. B. D., Zuber, M. N. B. A., Wong, W. J., Garcia, A., Vidal, L., Beisani, M., Pasquier, J., Vilallonga, R., Sharma, S., Parmar, C., Lee, L., Sufi, P., Sinan, H., and Saydam, M.

Subjects
Male, Pediatrics, medicine.medical_specialty, Coronavirus disease 2019 (COVID-19), Adolescent, Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), bariatric surgery, Context (language use), Pandemic, Medicine, Humans, Pandemics, COVID-19, pandemic, SARS-CoV-2, Nutrition and Dietetics, Manchester Cancer Research Centre, business.industry, Health Policy, ResearchInstitutes_Networks_Beacons/mcrc, Public Health, Environmental and Occupational Health, medicine.disease, Obesity, Obesity, Morbid, Treatment Outcome, Pediatrics, Perinatology and Child Health, Cohort, Female, Morbidity, business, Body mass index, Cohort study, Human
Abstract

Background: Metabolic and bariatric surgery (MBS) is an effective treatment for adolescents with severe obesity. Objectives: This study examined the safety of MBS in adolescents during the coronavirus disease 2019 (COVID-19) pandemic. Methods: This was a global, multicentre and observational cohort study of MBS performed between May 01, 2020, and October 10,2020, in 68 centres from 24 countries. Data collection included in-hospital and 30-day COVID-19 and surgery-specific morbidity/mortality. Results: One hundred and seventy adolescent patients (mean age: 17.75 ± 1.30 years), mostly females (n=122, 71.8%), underwent MBS during the study period. The mean pre-operative weight and body mass index were 122.16 ± 15.92 kg and 43.7± 7.11 kg/m2, respectively. Although majority of patients had pre-operative testing for severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) (n=146; 85.9%), only 42.4% (n=72) of the patients were asked to self-isolate pre-operatively. Two patients developed symptomatic SARS-CoV-2 infection post-operatively (1.2%). The overall complication rate was 5.3% (n=9). There was no mortality in this cohort. Conclusions: MBS in adolescents with obesity is safe during the COVID-19 pandemic when performed within the context of local precautionary procedures (such as pre-operative testing). The 30-day morbidity rates were similar to those reported pre-pandemic. These data will help facilitate the safe re-introduction of MBS services for this group of patients.

Published
2021

18. Global 30-day outcomes after bariatric surgery during the COVID-19 pandemic (GENEVA): an international cohort study

Author

Abou-Mrad-Fricquegnon, A, Alasfur, A, Alexandrou, A, Barbosa, A, Bashir, A, Bosco, A, Charalabopoulos, A, Curell, A, Davarpanah Jazi, A, Diego, A, Elghandour, A, Ergin, A, Garcia, A, Ghazal, A, Haddad, A, Ibarzábal, A, Khazraji, A, Lale, A, Lázaro, A, Leyva-Alvizo, A, Liagre, A, Maleckas, A, Osman, A, Pantelis, A, Pazouki, A, Plamper, A, Raziel, A, Rizzi, A, Sanchez, A, Sharma, A, Spaventa, A, Sumer, A, Torres, A, Türkçapar, A, Ugale, A, Velikorechin, A, Vitiello, A, Alkhaffaf, B, Bomans, B, Ammori, BJ, Pares, B, Smeu, B, Zilberstein, B, Boeker, C, Brodén, C, Copaescu, C, Guevara, C, Güldoğan, C, Kirkil, C, Matthys, C, Nagliati, C, Parmar, C, Trindade, C, Vaz, C, Wietzycoski, C, Zerrweck, C, Bedi, D, de Marchi, D, Faraj, D, Foschi, D, Goitein, D, Hazzan, D, Lapatsanis, D, Mazza, D, Mohammed, D, Padilla-Armendariz, D, Pennisi, D, Pham, D, Pournaras, D, Swank, D, Thakkar, D, Baena, E, Baili, E, Bastos, E, Dilektasli, E, Hazebroek, E, Kaplan, E, Lopes, E, Manno, E, Pinotti, E, Sdralis, E, Barrera-Rodriguez, F, Cantu, F, Jr., Frattini, F, Martini, F, Berardi, G, Cesana, G, Dapri, G, Dinescu, G, Juglard, G, Martinez de Aragon, G, Menaldi, G, Ören, G, Pavone, G, Rana, G, Vrakopoulou, G, Aboshanab, H, Al-Momani, H, Balamoun, H, Çiyiltepe, H, de Vasconcelos Cunha, H, Elghadban, H, Gislason, H, Hamed, H, Heneghan, H, Ibrahim, H, Melali, H, Reyes, H, Sebbag, H, Hakami, I, Hutopila, I, Balibrea, J, Bernardo, J, Campos, J, Chevallier, J, Dargent, J, Estrada, J, Gonzalez, J, Hewes, J, Himpens, J, Mall, J, Monterrubio, J, Pasquier, J, Albanopoulos, K, Bartosiak, K, Kaseja, K, Kumar, K, Rheinwalt, K, Shah, K, van de Pas, K., Angrisani, L, Benuzzi, L, Chong, L, Layani, L, Lee, L, Level, L, Taylor, L, Zinai, L, Akbaba, M, Alejandro, M, Altarawni, M, Beisani, M, Bertrand, M, Cantu, M, Dincer, M, Elbanna, M, Elfawal, M, Focquet, M, Forero, M, Hadad, M, Hii, M, Iovino, M, Islam, M, Josa, M, Kaplan, M, Kermansaravi, M, Khaitan, M, Kizilkaya, M, Kotowski, M, Montouri, M, Musella, M, Narwaria, M, Navarro, M, Niazi, M, Özmen, M, Qassem, M, Romeijn, M, Said, M, Salman, M, Solovyeva, M, Takieddine, M, Uccelli, M, Ustun, M, Valeti, M, Walędziak, M, Arora, N, Dukkipati, N, Fearon, N, Kiran, N, Paleari, N, Sakran, N, Silva, N, Tartaglia, N, Savas, O, Şen, O, Viveiros, O, Fabbri, P, García, P, Major, P, Martinez, P, Martinez Duartez, P, Salminen, P, Shah, P, Gadani, R, Gokay, R, Gudaityte, R, Kassir, R, Liem, R, Mohan, R, Palma, R, Quinino, R, Ribeiro, R, Vilallonga, R, Arana-Garza, S, Chiappetta, S, Davakis, S, Ghareeb, S, Gregorio, S, Khaldi, S, Martinez, S, Okkema, S, Olmi, S, Ortiz, S, Pinango, S, Shah, S, Shahabi, S, Taha, S, Ugale, S, Barreiro, T, Beck, T, Poghosyan, T, Samarkandy, T, Yigit, T, Borrelli, V, Bottino, V, Marco, V, Ormando, V, Pol, V, Sierra Esteban, V, Valentí, V, Leclercq, W, Souza, W, Vening, W, Vleeschouwers, W, van der Burgh, Y, Singhal, Rishi, Tahrani, Abd A, Ludwig, Christian, and Mahawar, Kamal

Published
2021
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19. Multi-scale shock-to-detonation simulation of pressed energetic material: A meso-informed ignition and growth model.

Author

Sen, O., Rai, N. K., Diggs, A. S., Hardin, D. B., and Udaykumar, H. S.

Subjects
*MULTISCALE modeling, *MATHEMATICAL models, *DETONATION waves, *SHOCK waves, *SPARK plugs
Abstract

This work presents a multiscale modeling framework for predictive simulations of shock-to-detonation transition (SDT) in pressed energetic (HMX) materials. The macro-scale computations of SDT are performed using an ignition and growth (IG) model. However, unlike in the traditional semi-empirical ignition-and-growth model, which relies on empirical fits, in this work meso-scale void collapse simulations are used to supply the ignition and growth rates. This results in a macro-scale model which is sensitive to the meso-structure of the energetic material. Energy localization at the meso-scale due to hotspot ignition and growth is reflected in the shock response of the energetic material via surrogate models for ignition and growth rates. Ensembles of meso-scale reactive void collapse simulations are used to train the surrogate model using a Bayesian Kriging approach. This meso-informed Ignition and Growth (MES-IG) model is applied to perform SDT simulations of pressed HMXs with different porosity and void diameters. The computations are successfully validated against experimental pop-plots. Additionally, the critical energy for SDT is computed and the experimentally observed P s 2 τ s = constant relations are recovered using the MES-IG model. While the multiscale framework in this paper is applied in the context of an ignition-and-growth model, the overall surrogate model-based multiscale approach can be adapted to any macro-scale model for predicting SDT in heterogeneous energetic materials. [ABSTRACT FROM AUTHOR]

Published
2018
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20. Influence Of African Atmospheric Rivers On Precipitation And Snowmelt In The Near East'S Highlands

Author

Bozkurt, D., Sen, O. L., Ezber, Y., Guan, B., Viale, M., and Caglar, F.

Abstract

Atmospheric rivers (ARs) traveling thousands of kilometers over arid North Africa could interact with the highlands of the Near East (NE), and thus affect the region's hydrometeorology and water resources. Here, we use a state-of-the-art AR tracking database, and reanalysis and observational datasets to investigate the climatology (1979-2017) and influences of these ARs in snowmelt season (March-April). The Red Sea and northeast Africa are found to be the major source regions of these ARs, which are typically associated with the eastern Mediterranean trough positioned over the Balkan Peninsula and a blocking anticyclone over the NE-Caspian region, triggering southwesterly air flow toward the NE's highlands. Approximately 8% of the ARs are relatively strong (integrated water vapor transport >similar to 275 kg m(-1) s(-1)). AR days exhibit enhanced precipitation over the crescent-shaped orography of the NE region. Mean AR days indicate wetter (up to + 2 mm day(-1)) and warmer (up to + 1.5 degrees C) conditions than all-day climatology. On AR days, while snowpack tends to decrease (up to 30%) in the Zagros Mountains, it can show decreases or increases in the Taurus Mountains depending largely on elevation. A further analysis with the observations and reanalysis indicates that extreme ARs coinciding with large scale sensible heat transport can significantly increase the daily discharges. These results suggest that ARs can have notable impacts on the hydrometeorology and water resources of the region, particularly of lowland Mesopotamia, a region that is famous with great floods in the ancient narratives.

Published
2021

30. Scaling Law for Criticality Conditions in Heterogeneous Energetic Materials under Shock Loading

Author

Nassar, A., Rai, N. K., Sen, O., and Udaykumar, H. S.

Subjects
FOS: Physical sciences, Physics - Applied Physics, Applied Physics (physics.app-ph), Computational Physics (physics.comp-ph), Physics - Computational Physics
Abstract

Initiation in heterogeneous energetic material (HEM) subjected to shock loading occurs due to the formation of hot spots. The criticality of the hot spots governs the initiation and sensitivity of HEMs. In porous energetic materials, collapse of pores under impact leads to the formation of hot spots. Depending on the size and strength of the hot spots chemical reaction can initiate. The criticality of the hot spots is dependent on the imposed shock load, void morphology and the type of energetic material. This work evaluates the relative importance of material constitutive and reactive properties on the criticality condition of spots. Using a scaling-based approach, the criticality criterion for cylindrical voids as a function of shock pressure, Ps and void diameter, Dvoid is obtained for two different energetic material HMX and TATB. It is shown that the criticality of different energetic materials is significantly dependent on their reactive properties.

Published
2019
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32. Comparison of Symptom Severity and Progression in Advanced Cancer Patients Among Different Care Settings: A Secondary Analysis

Author

Ryuto Shiraishi, Yoshiyuki Kizawa, Masanori Mori, Isseki Maeda, Yutaka Hatano, Hiroto Ishiki, Tomofumi Miura, Naosuke Yokomichi, Maiko Kodama, Keiko Inoue, Sen Otomo, Takashi Yamaguchi, and Jun Hamano

Subjects
advanced cancer patients, multicenter prospective cohort studies, palliative care at home, palliative care units, place of care, symptom management, Medicine (General), R5-920
Abstract

Background: Most people in Japan wish to spend their final days at home, but the majority fail to do so; earlier studies indicated a more pronounced worsening of symptoms if treated at home. Objectives: This study compared the prevalence of symptom worsening and explored associated factors between patients with advanced cancer receiving palliative care in palliative care units (PCUs) and at home. Design: We conducted a secondary analysis of two multicenter, prospective cohort studies involving patients with advanced cancer receiving palliative care in PCUs or at home. Setting/Subjects: One study was conducted at 23 PCUs (January to December 2017) and the other on 45 palliative home care services (July to December 2017) in Japan. Measurements: Symptom changes were categorized as stable, improved, or worse. Results: Of the 2998 registered patients, 2877 were analyzed. Among them, 1890 patients received palliative care in PCUs, and 987 at home. Patients receiving palliative care at home were more likely to have worsening of pain (17.1% vs. 3.8%; p?0.001) and drowsiness (32.6% vs. 22.2%; p?

Published
2023
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33. Unresolved Palliative Care Needs of Elderly Non-Cancer Patients at Home: A Multicenter Prospective Study

Author

Jun Hamano, Takuya Shinjo, Kazuhiko Fukumoto, Maiko Kodama, Hongja Kim, Sen Otomo, Shoichi Masumoto, Kotaro Hashimoto, Takamichi Matsuki, Kazuhiro Hisajima, Nobuyuki Miyata, Riri Suzuki, Shoji Yokoya, Keijiro Miyake, Ryo Takayanagi, Masakatsu Shimizu, Yoshihiro Kataoka, Hiroshi Taira, Sachiko Ozone, Hiroki Takahashi, and Yoshiyuki Kizawa

Subjects
Computer applications to medicine. Medical informatics, R858-859.7, Public aspects of medicine, RA1-1270
Abstract

Introduction/Objectives: There is growing consensus on the benefits of initiating palliative care early in the disease trajectory; however, palliative care needs for non-cancer patients remain to be elucidated. We investigated the trajectory of unresolved palliative care needs of non-cancer patients at home and explored associated factors. Methods: We conducted a multicenter prospective cohort study of elderly non-cancer patients at home in Japan between Jan 2020 and Dec 2020. Physicians assessed their palliative care needs using the Integrated Palliative Care Outcome Scale (IPOS). Unresolved palliative care needs were defined as IPOS symptoms above 2 (moderate). Results: In total, 785 patients were enrolled. The most frequent unresolved palliative care needs at enrollment were poor mobility (n = 438, 55.8%), followed by weakness/lack of energy (n = 181, 23.1%) and poor appetite (n = 160, 20.4%). Multivariate logistic regression analysis revealed that female and musculoskeletal disease were significantly positively associated with pain at starting home visits (OR = 1.89, P = .015; OR = 2.69, P = .005). In addition, neurological diseases were significantly positively associated with constipation and poor mobility 3 months after starting home visits (OR = 3.75, P = .047; OR = 3.04, P = .009). Conclusions: The order of the prevalence of unresolved palliative care needs may remain relatively stable over time, even for those receiving home-based palliative care services. We identified several specific diseases and conditions that were significantly associated with unresolved palliative care needs.

Published
2023
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34. Kinase inhibition profiles as a tool to identify kinases for specific phosphorylation sites

Author

Watson, N. A., Cartwright, T. N., Lawless, C., Cﾃ｡mara-Donoso, M., Sen, O., Sako, K., Hirota, T., Kimura, Hiroshi, and Higgins, J. M. G.

Subjects
0301 basic medicine, Chromosomal Proteins, Non-Histone, General Physics and Astronomy, 0302 clinical medicine, Genetic Testing/*methods, Phosphorylation, lcsh:Science, Cyclin, Recombinant Proteins/metabolism, Multidisciplinary, DNA-Binding Proteins/metabolism, biology, Kinase, INCENP, Cheminformatics, Autophosphorylation, High-throughput screening, Phosphorylation/drug effects, Recombinant Proteins, Cell biology, DNA-Binding Proteins, Histone, High-Throughput Screening Assays/*methods, In silico, Science, Protein Kinases/*metabolism, Mitosis, Kinases, Chromosomal Proteins, Non-Histone/metabolism, General Biochemistry, Genetics and Molecular Biology, Article, 03 medical and health sciences, Protein Kinase Inhibitors/*pharmacology, Humans, Transcription Factors/metabolism, Genetic Testing, Protein Kinase Inhibitors, Enzyme Assays, General Chemistry, High-Throughput Screening Assays, 030104 developmental biology, biology.protein, lcsh:Q, Protein Kinases, 030217 neurology & neurosurgery, Transcription Factors, HeLa Cells
Abstract

There are thousands of known cellular phosphorylation sites, but the paucity of ways to identify kinases for particular phosphorylation events remains a major roadblock for understanding kinase signaling. To address this, we here develop a generally applicable method that exploits the large number of kinase inhibitors that have been profiled on near-kinome-wide panels of protein kinases. The inhibition profile for each kinase provides a fingerprint that allows identification of unknown kinases acting on target phosphosites in cell extracts. We validate the method on diverse known kinase-phosphosite pairs, including histone kinases, EGFR autophosphorylation, and Integrin β1 phosphorylation by Src-family kinases. We also use our approach to identify the previously unknown kinases responsible for phosphorylation of INCENP at a site within a commonly phosphorylated motif in mitosis (a non-canonical target of Cyclin B-Cdk1), and of BCL9L at S915 (PKA). We show that the method has clear advantages over in silico and genetic screening., Identifying kinases responsible for specific phosphorylation events remains challenging. Here, the authors leverage kinase inhibitor profiles for the identification of kinase-substrate site pairs in cell extracts, developing a method that can identify the enzymes responsible for unassigned phosphorylation events.

Published
2020

39. Von Hippel-Lindau status influences phenotype of liver cancers arising from PTEN loss

Author

Sendor AB, Hacker KE, Chen S, Corona AL, Sen O, Chiang DY, Snavely A, Rogers AB, Montgomery SA, Rathmell WK, and McRee AJ

Subjects
lcsh:Diseases of the digestive system. Gastroenterology, lcsh:RC799-869, lcsh:Neoplasms. Tumors. Oncology. Including cancer and carcinogens, lcsh:RC254-282
Abstract

Adam B Sendor,1 Kathryn E Hacker,1 Shufen Chen,1 Armando L Corona,1 Oishee Sen,1 Derek Y Chiang,1 Anna Snavely,1 Arlin B Rogers,2 Stephanie A Montgomery,1 W Kimryn Rathmell,1 Autumn J McRee11Lineberger Comprehensive Cancer Center, University of North Carolina, Chapel Hill, NC, USA; 2Section of Pathology, Department of Biomedical Sciences, Cummings School of Veterinary Medicine, Tufts University, Boston, MA, USABackground: PTEN loss contributes to the development of liver diseases including hepatic steatosis and both hepatocellular carcinoma (HCC) and cholangiocarcinoma (CC). The factors that influence the penetrance of these conditions are unclear. We explored the influence of sustained hypoxia signaling through co-deletion of Pten and Vhl in a murine model.Methods: We used a CreER-linked Keratin 18 mouse model to conditionally delete Pten, Vhl or both in somatic cells of adult mice, evaluating the resultant tumors by histology and gene expression microarray. Existing sets of gene expression data for human HCC and CC were examined for pathways related to those observed in the murine tumors, and a cohort of human CC samples was evaluated for relationships between HIF-1α expression and clinical outcomes.Results: Both Pten deletion genotypes developed liver tumors, but with differing phenotypes. Pten deletion alone led to large hepatic tumors with widespread hepatosteatosis. Co-deletion of Pten and Vhl with the Keratin 18 promoter resulted in reduced steatosis and a reduced tumor burden that was characterized by a trabecular architecture similar to CC. Genes associated with hepatic steatosis were coordinately expressed in the human HCC dataset, while genes involved in hypoxia response were upregulated in tumors from the human CC dataset. HIF-1α expression and overall survival were examined in an independent cohort of human CC tumors with no statistical differences uncovered.Conclusion: Pten deletion in Keratin 18 expressing cells leads to aggressive tumor formation and widespread steatosis in mouse livers. Co-deletion of Vhl and Pten results in lower tumor burden with gene expression profiling suggesting a switch from a profile of lipid deposition to an expression profile more consistent with upregulation of the hypoxia response pathway. A relationship between tumor hypoxia signaling and altered hepatic steatotic response suggests that competing influences may alter tumor phenotypes.Keywords: Von Hippel-Lindau (VHL), phosphatase and tension homologue deleted on chromosome 10 (PTEN), cholangiocarcinoma (CC), hepatocellular-cholangiocarcinoma (HCC)

Published
2015

40. Thermally exfoliated graphene oxide reinforced fluorinated pentablock poly(L-lactide-co-epsilon-caprolactone) electrospun scaffolds: Insight into antimicrobial activity and biodegradation

Author

Okan, BS, Marset, A, Zanjani, JSM, Sut, PA, Sen, O, Culha, M, Menceloglu, Y, Okan, BS, Marset, A, Zanjani, JSM, Sut, PA, Sen, O, Culha, M, Menceloglu, Y, and Yeditepe Üniversitesi

Subjects
graphene and fullerenes, copolymers, biodegradable, surfaces and interfaces, electrospinning, nanotubes
Abstract

Three-dimensional fluorinated pentablock poly(L-lactide-co-epsilon-caprolactone)-based scaffolds were successfully produced by the incorporation of thermally exfoliated graphene oxide (TEGO) as an antimicrobial agent with an electrospinning technique. In a ring-opening polymerization, the fluorinated groups in the middle of polymer backbone were attached with a perfluorinated reactive stabilizer having oxygen-carrying ability. The fiber diameter and its morphologies were optimized through changes in TEGO amount, voltage, polymer concentration, and solvent type to obtain an ideal scaffold structure. Instead of the widely used graphene oxide synthesized by Hummer's method, TEGO sheets having a low amount of oxygen produced by thermal expansion were integrated into the fiber structure to investigate the effect of the oxygen functional groups of TEGO sheets on the degradation and antimicrobial activity of the scaffolds. There was no antimicrobial activity in TEGO-reinforced scaffolds in the in vitro tests in contrast to the literature. This study confirmed that a low number of oxygen functional groups on the surface of TEGO restricted the antimicrobial activity of the fabricated composite scaffolds. (C) 2016 Wiley Periodicals, Inc.

Published
2016

43. Research on optimization strategy of urban medium voltage direct current distribution network construction considering application scenarios

Author

Sen Ouyang, Xi Xin, Fengxue Wang, Yi Huang, and Moyuan Yang

Subjects
comprehensive evaluation index system, distribution network planning, medium voltage DC distribution network, optimal selection analysis method, urban scene demand, Distribution or transmission of electric power, TK3001-3521, Production of electric energy or power. Powerplants. Central stations, TK1001-1841
Abstract

Abstract In the distribution network planning work, taking into account the constraints of funds and construction annual plan, there is always the prioritization problem of multiple MVDC distribution networks. Aiming at the problem, this paper proposes a method for the optimization analysis of MVDC distribution network planning objects. Firstly, a comprehensive evaluation index system of urban MVDC distribution network planning and optimization is established from three aspects of improving power supply reliability and the quality of voltage, MVDC distribution network scenario types and distribution network social benefits. Then, the qualitative indexes are quantified based on the cloud model, and the comprehensive evaluation values of each distribution network are calculated and sorted by the hierarchical additive weighting of Delphi entropy weight method. Taking the maximum comprehensive evaluation value of the scheme as objective function and the annual total investment as constraint, the construction priority of multiple MVDC distribution networks is determined. Finally, taking several distribution networks in Guangzhou, Guangdong Province, China as examples, the simulation results show that the optimal objects of distribution network based on the urban scenario demands are X4, X8 and X1, with the lowest total investment cost of 19,180 yuan, thus verifying the effectiveness of the proposed method.

Published
2022
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46. 3D Bioprinting of branched vessel constructs

Author

Koc, B, Kucukgul, C, Ozler, SB, Altunbek, M, Sen, O, Culha, M, Koc, B, Kucukgul, C, Ozler, SB, Altunbek, M, Sen, O, Culha, M, and Yeditepe Üniversitesi

Abstract

…

Published
2014

48. High resolution [super 15]N NMR of the 225 K phase transition of ammonia borane (N[H.sub.3]B[H.sub.3]): Mixed order-disorder and displacive behavior

Author

Gunaydin-Sen, O., Achey, R., Dalal, N. S., Stowe, A., and Autrey, T.

Subjects
Nuclear magnetic resonance -- Usage, Ammonia -- Mechanical properties, Ammonia -- Chemical properties, Ammonia -- Spectra, Borane -- Mechanical properties, Borane -- Chemical properties, Borane -- Spectra, Chemicals, plastics and rubber industries
Abstract

The high resolution [super 15]N NMR probing of the solid-solid phase transition of ammonia borane (N[H.sub.3]B[H.sub.3]) is analyzed. The results show that there exists a mixed order-disorder and displacive behavior in the transition of ammonia, as its rotor motion plays a very important role in the transition mechanism.

Published
2007

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