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1. Data quality control system and long-term performance monitor of the LHAASO-KM2A

Author

Cao, Zhen, Aharonian, F., Axikegu, Bai, Y. X., Bao, Y. W., Bastieri, D., Bi, X. J., Bi, Y. J., Bian, W., Bukevich, A. V., Cao, Q., Cao, W. Y., Cao, Zhe, Chang, J., Chang, J. F., Chen, A. M., Chen, E. S., Chen, H. X., Chen, Liang, Chen, Lin, Chen, Long, Chen, M. J., Chen, M. L., Chen, Q. H., Chen, S., Chen, S. H., Chen, S. Z., Chen, T. L., Chen, Y., Cheng, N., Cheng, Y. D., Cui, M. Y., Cui, S. W., Cui, X. H., Cui, Y. D., Dai, B. Z., Dai, H. L., Dai, Z. G., Danzengluobu, Dong, X. Q., Duan, K. K., Fan, J. H., Fan, Y. Z., Fang, J., Fang, J. H., Fang, K., Feng, C. F., Feng, H., Feng, L., Feng, S. H., Feng, X. T., Feng, Y., Feng, Y. L., Gabici, S., Gao, B., Gao, C. D., Gao, Q., Gao, W., Gao, W. K., Ge, M. M., Geng, L. S., Giacinti, G., Gong, G. H., Gou, Q. B., Gu, M. H., Guo, F. L., Guo, X. L., Guo, Y. Q., Guo, Y. Y., Han, Y. A., Hasan, M., He, H. H., He, H. N., He, J. Y., He, Y., Hor, Y. K., Hou, B. W., Hou, C., Hou, X., Hu, H. B., Hu, Q., Hu, S. C., Huang, D. H., Huang, T. Q., Huang, W. J., Huang, X. T., Huang, X. Y., Huang, Y., Ji, X. L., Jia, H. Y., Jia, K., Jiang, K., Jiang, X. W., Jiang, Z. J., Jin, M., Kang, M. M., Karpikov, I., Kuleshov, D., Kurinov, K., Li, B. B., Li, C. M., Li, Cheng, Li, Cong, Li, D., Li, F., Li, H. B., Li, H. C., Li, Jian, Li, Jie, Li, K., Li, S. D., Li, W. L., Li, X. R., Li, Xin, Li, Y. Z., Li, Zhe, Li, Zhuo, Liang, E. W., Liang, Y. F., Lin, S. J., Liu, B., Liu, C., Liu, D., Liu, D. B., Liu, H., Liu, H. D., Liu, J., Liu, J. L., Liu, M. Y., Liu, R. Y., Liu, S. M., Liu, W., Liu, Y., Liu, Y. N., Luo, Q., Luo, Y., Lv, H. K., Ma, B. Q., Ma, L. L., Ma, X. H., Mao, J. R., Min, Z., Mitthumsiri, W., Mu, H. J., Nan, Y. C., Neronov, A., Ou, L. J., Pattarakijwanich, P., Pei, Z. Y., Qi, J. C., Qi, M. Y., Qiao, B. Q., Qin, J. J., Raza, A., Ruffolo, D., Sáiz, A., Saeed, M., Semikoz, D., Shao, L., Shchegolev, O., Sheng, X. D., Shu, F. W., Song, H. C., Stenkin, Yu. V., Stepanov, V., Su, Y., Sun, D. X., Sun, Q. N., Sun, X. N., Sun, Z. B., Takata, J., Tam, P. H. T., Tang, Q. W., Tang, R., Tang, Z. B., Tian, W. W., Wang, C., Wang, C. B., Wang, G. W., Wang, H. G., Wang, H. H., Wang, J. C., Wang, Kai, Wang, L. P., Wang, L. Y., Wang, P. H., Wang, R., Wang, W., Wang, X. G., Wang, X. Y., Wang, Y., Wang, Y. D., Wang, Y. J., Wang, Z. H., Wang, Z. X., Wang, Zhen, Wang, Zheng, Wei, D. M., Wei, J. J., Wei, Y. J., Wen, T., Wu, C. Y., Wu, H. R., Wu, Q. W., Wu, S., Wu, X. F., Wu, Y. S., Xi, S. Q., Xia, J., Xiang, G. M., Xiao, D. X., Xiao, G., Xin, Y. L., Xing, Y., Xiong, D. R., Xiong, Z., Xu, D. L., Xu, R. F., Xu, R. X., Xu, W. L., Xue, L., Yan, D. H., Yan, J. Z., Yan, T., Yang, C. W., Yang, C. Y., Yang, F., Yang, F. F., Yang, L. L., Yang, M. J., Yang, R. Z., Yang, W. X., Yao, Y. H., Yao, Z. G., Yin, L. Q., Yin, N., You, X. H., You, Z. Y., Yu, Y. H., Yuan, Q., Yue, H., Zeng, H. D., Zeng, T. X., Zeng, W., Zha, M., Zhang, B. B., Zhang, F., Zhang, H., Zhang, H. M., Zhang, H. Y., Zhang, J. L., Zhang, Li, Zhang, P. F., Zhang, P. P., Zhang, R., Zhang, S. B., Zhang, S. R., Zhang, S. S., Zhang, X., Zhang, X. P., Zhang, Y. F., Zhang, Yi, Zhang, Yong, Zhao, B., Zhao, J., Zhao, L., Zhao, L. Z., Zhao, S. P., Zhao, X. H., Zheng, F., Zhong, W. J., Zhou, B., Zhou, H., Zhou, J. N., Zhou, M., Zhou, P., Zhou, R., Zhou, X. X., Zhu, B. Y., Zhu, C. G., Zhu, F. R., Zhu, H., Zhu, K. J., Zou, Y. C., and Zuo, X.

Subjects
Astrophysics - Instrumentation and Methods for Astrophysics, High Energy Physics - Experiment, Physics - Instrumentation and Detectors
Abstract

The KM2A is the largest sub-array of the Large High Altitude Air Shower Observatory (LHAASO). It consists of 5216 electromagnetic particle detectors (EDs) and 1188 muon detectors (MDs). The data recorded by the EDs and MDs are used to reconstruct primary information of cosmic ray and gamma-ray showers. This information is used for physical analysis in gamma-ray astronomy and cosmic ray physics. To ensure the reliability of the LHAASO-KM2A data, a three-level quality control system has been established. It is used to monitor the status of detector units, stability of reconstructed parameters and the performance of the array based on observations of the Crab Nebula and Moon shadow. This paper will introduce the control system and its application on the LHAASO-KM2A data collected from August 2021 to July 2023. During this period, the pointing and angular resolution of the array were stable. From the observations of the Moon shadow and Crab Nebula, the results achieved using the two methods are consistent with each other. According to the observation of the Crab Nebula at energies from 25 TeV to 100 TeV, the time averaged pointing errors are estimated to be $-0.003^{\circ} \pm 0.005^{\circ}$ and $0.001^{\circ} \pm 0.006^{\circ}$ in the R.A. and Dec directions, respectively., Comment: 15 pages, 9 figures

Published
2024

4. Two Kinetically Different Supercooled Liquids -- Potential Energy Landscape Perspective

Author

Zhang, B., Zhang, D. M., Sun, D. Y., and Gong, X. G.

Subjects
Condensed Matter - Soft Condensed Matter, Condensed Matter - Materials Science
Abstract

During the process of rapid cooling, two distinct types of supercooled liquids are found. One kind of supercooled liquids destines to crystallize (the crystal-forming liquid (GFL)), and the other forms a glass (the glass-forming liquid (GFL)). Despite having no significant differences in conventional physical quantities such as structure and energy, the distribution of the potential energy after short-time averaging reveals the emergence of distinction. By analyzing the skewness of the potential energy distribution after the short-time average, a new characteristic time ($\Delta_{CTS)}$) emerges. For a given temperature, the skewness reaches an extremum when the duration of the short-time average equals this characteristic time. Interestingly, this characteristic time scale follows a Curie-like law ($\Delta_{CTS}\sim 1/(T-T^{*})^{{\gamma}}$) with an exponent $\gamma$, which effectively distinguishes these two types of supercooled liquids. The value of $\gamma$ undergoes a discontinuous transition at the critical cooling rate. The value of $\gamma_{g}$, corresponding to GFL, is always greater than $\gamma_{c}$ associated with CFL. Remarkably, $T^{*}$ precisely represents the glass transition temperature (Tg ) or the crystallization temperature (Tc ) for GFL and CFL, respectively. Theoretical analysis suggests that, the Curie-like law implies a kinetic phase transition. The essential difference between these two types of supercooled liquids lies in the different in local potential energy landscapes. First, the atomic motion in GFL may have more strong correlation than that in CFL. Second, CFL may possess a lower configurational entropy than GFL. The current study not only delineates the differentiation between the two types of supercooled liquids, but also provides a new perspective for exploring the nature of glasses., Comment: 7 figures 24 pages

Published
2023

7. Reduced Graphene Oxide Fibers Combined with Electrical Stimulation Promote Peripheral Nerve Regeneration

Author

Zhao Y, Liu Y, Lu C, Sun D, Kang S, Wang X, and Lu L

Subjects
peripheral nerve defects, sciatic nerve injury, functional recovery, tissue engineering, conductive materials, Medicine (General), R5-920
Abstract

Yuanyuan Zhao,1 Yang Liu,1 Cheng Lu,1 Daokuan Sun,2 Shiqi Kang,1 Xin Wang,2,* Laijin Lu1,* 1Department of Hand and Podiatric Surgery, Orthopedics Center, The First Hospital of Jilin University, Changchun, Jilin, People’s Republic of China; 2School of Materials Science and Engineering, Jilin University, Changchun, Jilin, People’s Republic of China*These authors contributed equally to this workCorrespondence: Laijin Lu, Department of Hand and Podiatric Surgery, Orthopedics Center, The First Hospital of Jilin University, Changchun, Jilin, People’s Republic of China, Tel +86-13756661203, Fax +86 431 84808391, Email ljlu@jlu.edu.cn Xin Wang, School of Materials Science and Engineering, Jilin University, Changchun, Jilin, People’s Republic of China, Tel +86-18 626 655 395, Fax +86 431 84 808 391, Email wang_xin@jlu.edu.cnBackground: The treatment of long-gap peripheral nerve injury (PNI) is still a substantial clinical problem. Graphene-based scaffolds possess extracellular matrix (ECM) characteristic and can conduct electrical signals, therefore have been investigated for repairing PNI. Combined with electrical stimulation (ES), a well performance should be expected. We aimed to determine the effects of reduced graphene oxide fibers (rGOFs) combined with ES on PNI repair in vivo.Methods: rGOFs were prepared by one-step dimensionally confined hydrothermal strategy (DCH). Surface characteristics, chemical compositions, electrical and mechanical properties of the samples were characterized. The biocompatibility of the rGOFs were systematically explored both in vitro and in vivo. Total of 54 Sprague-Dawley (SD) rats were randomized into 6 experimental groups: a silicone conduit (S), S+ES, S+rGOFs-filled conduit (SGC), SGC+ES, nerve autograft, and sham groups for a 10-mm sciatic defect. Functional and histological recovery of the regenerated sciatic nerve at 12 weeks after surgery in each group of SD rats were evaluated.Results: rGOFs exhibited aligned micro- and nano-channels with excellent mechanical and electrical properties. They are biocompatible in vitro and in vivo. All 6 groups exhibited PNI repair outcomes in view of neurological and morphological recovery. The SGC+ES group achieved similar therapeutic effects as nerve autograft group (P > 0.05), significantly outperformed other treatment groups. Immunohistochemical analysis showed that the expression of proteins related to axonal regeneration and angiogenesis were relatively higher in the SGC+ES.Conclusion: The rGOFs had good biocompatibility combined with excellent electrical and mechanical properties. Combined with ES, the rGOFs provided superior motor nerve recovery for a 10-mm nerve gap in a murine acute transection injury model, indicating its excellent repairing ability. That the similar therapeutic effects as autologous nerve transplantation make us believe this method is a promising way to treat peripheral nerve defects, which is expected to guide clinical practice in the future.Keywords: peripheral nerve defects, sciatic nerve injury, functional recovery, tissue engineering, conductive materials

Published
2024

8. Association Between Serum Anion Gap and Mortality in Critically Ill Patients with COPD in ICU: Data from the MIMIC IV Database

Author

Chen X, Yang Q, Gao L, Chen W, Gao X, Li Y, Ao L, and Sun D

Subjects
ag, copd, mortality, mimic iv, Diseases of the respiratory system, RC705-779
Abstract

Xiaojing Chen,1– 3,&ast; Qilin Yang,4,&ast; Li Gao,1– 3 Weinan Chen,1 Xiaoyu Gao,1– 3 Yameng Li,1– 3 Liying Ao,5 Dejun Sun1– 3 1Department of Respiratory and Critical Care Medicine, Inner Mongolia People’s Hospital, Hohhot, 010017, People’s Republic of China; 2NHC Key Laboratory of Diagnosis & Treatment of COPD, Inner Mongolia People’s Hospital, Hohhot, 010017, People’s Republic of China; 3Inner Mongolia Key Laboratory of Respiratory Diseases, Inner Mongolia People’s Hospital, Hohhot, 010017, People’s Republic of China; 4Department of Critical Care, the Second Affiliated Hospital of Guangzhou Medical University, Guangzhou, People’s Republic of China; 5Department of Otolaryngology, Inner Mongolia People’s Hospital, Hohhot, 010017, People’s Republic of China&ast;These authors contributed equally to this workCorrespondence: Dejun Sun, Department of Respiratory and Critical Care Medicine, Inner Mongolia People’s Hospital, No. 26 Zhaowuda Road, Saihan District, Hohhot, 010017, People’s Republic of China, Email nmg_sdj@163.comBackground: Serum anion gap (AG) has been proven to be associated with prognosis in critically ill patients. However, few studies have investigated the association between AG and all-cause mortality in critically ill patients with chronic obstructive pulmonary disease (COPD).Objective: We hypothesized that the initial AG level would predict the mortality risk in critically ill patients with COPD.Methods: This retrospective cohort study was based on the Medical Information Mart for Intensive Care (MIMIC) IV database. We extracted demographics, vital signs, laboratory tests, comorbidity, and scoring systems from the first 24 hours after patient ICU admission. Multivariable logistic regression analysis models were used to explore the association between serum AG levels and mortality. Interaction and stratified analyses were conducted including age, gender and comorbidity.Results: A total of 5531 critically ill patients with COPD were enrolled, composed of 53.6% male and 46.4% female with a median age of 73 years. The all-cause mortality of these patients during ICU hospitalization was 13.7%. The risk of all-cause mortality increased as the AG level increased in the univariate logistic regression analysis (OR=1.13, 95% CI: 1.11– 1.15, p< 0.01). After adjusting for all the covariates in multivariate logistic regression analysis, the odds ratio was 1.06 (95% CI: 1.04– 1.09, p< 0.01). Compared with the lowest AG group Q1 (≤ 11mmol/L), the adjusted OR value for AG and mortality in Q2 (12– 13mmol/L) was 0.89 (95% CI: 0.63– 1.25, p=0.502), Q3 (14– 15mmol/L) was 0.95 (95% CI: 0.68– 1.34, p=0.788), and Q4 (≥ 16mmol/L) was 1.49 (95% CI: 1.10– 2.02, p=0.009) respectively. In addition, the results of the subgroup and stratified analyses were robust.Conclusion: AG is positively related to all-cause mortality in critically ill patients with COPD.Keywords: AG, COPD, mortality, MIMIC IV

Published
2024

9. A TA/Cu2+ Nanoparticle Enhanced Carboxymethyl Chitosan-Based Hydrogel Dressing with Antioxidant Properties and Promoting Wound Healing

Author

Huang Y, Chen Y, Cheng G, Li W, Zhang H, Yu C, Fang J, Zuo J, Li Y, Xu L, and Sun D

Subjects
ta/cu2+ nanoparticles, carboxymethyl chitosan, wound dressing, antioxidant activity, Medicine (General), R5-920
Abstract

Yongjun Huang,1,&ast; Yong Chen,2,&ast; Guoyun Cheng,1,&ast; Wenqiang Li,3 Hongan Zhang,1,4 Chaoqun Yu,1 Jia Fang,1 Jieyi Zuo,1 Ying Li,1 Lei Xu,1 Dawei Sun1 1Department of Orthopedics, Guangdong Second Provincial General Hospital, Guangzhou, 510317, People’s Republic of China; 2Department of Orthopedics, The Sixth Affiliated Hospital of Guangzhou Medical University, Qingyuan, People’s Hospital, Qingyuan, 511518, People’s Republic of China; 3Engineering Technology Research Center for Sports Assistive Devices of Guangdong, Guangzhou Sport University, Guangzhou, 510500, People’s Republic of China; 4The Second Clinical School of Medicine, Southern Medical University, Guangzhou, 510260, People’s Republic of China&ast;These authors contributed equally to this workCorrespondence: Lei Xu; Dawei Sun, Department of Orthopedics, Guangdong Second Provincial General Hospital, 11th Floor, Building 3, No. 466, Xingang Middle Road, Guangzhou, Guangdong Province, 510317, People’s Republic of China, Email orthoxl@163.com; sundw@gd2h.org.cnBackground: As the first line of immune defense and the largest organ of body, skin is vulnerable to damage caused by surgery, burns, collisions and other factors. Wound healing in the skin is a long and complex physiological process that is influenced by a number of different factors. Proper wound care can greatly improve the speed of wound healing and reduce the generation of scars. However, traditional wound dressings (bandages, gauze, etc.) often used in clinical practice have a single function, lack of active ingredients and are limited in use. Hydrogels with three-dimensional network structure are a potential biomedical material because of their physical and chemical environment similar to extracellular matrix. In particular, hydrogel dressings with low price, good biocompatibility, degradability, antibacterial and angiogenic activity are favored by the public.Methods: Here, a carboxymethyl chitosan-based hydrogel dressing (CMCS-TA/Cu2+) reinforced by copper ion crosslinked tannic acid (TA/Cu2+) nanoparticles was developed. This study investigated the physical and chemical characteristics, cytotoxicity, and angiogenesis of TA/Cu2+ nanoparticles and CMCS-TA/Cu2+ hydrogels. Furthermore, a full-thickness skin defect wound model was employed to assess the in vivo wound healing capacity of hydrogel dressings.Results: The introduction of TA/Cu2+ nanoparticles not only could increase the mechanical properties of the hydrogel but also continuously releases copper ions to promote cell migration (the cell migration could reach 92% at 48 h) and tubule formation, remove free radicals and promote wound healing (repair rate could reach 90% at 9 days).Conclusion: Experiments have proved that CMCS-TA/Cu2+ hydrogel has good cytocompatibility, antioxidant and wound healing ability, providing an advantageous solution for skin repair. Keywords: TA/Cu2+ nanoparticles, carboxymethyl chitosan, wound dressing, antioxidant activity

Published
2024

10. Exploration of Wire Array Metamaterials for the Plasma Axion Haloscope

Author

Wooten, M., Droster, A., Kenany, Al, Sun, D., Lewis, S. M., and van Bibber, K.

Subjects
High Energy Physics - Experiment, Astrophysics - Instrumentation and Methods for Astrophysics
Abstract

A plasma haloscope has recently been proposed as a feasible approach to extend the search for dark matter axions above 10 GHz ($\sim$ 40 $\mu$eV), whereby the microwave cavity in a conventional axion haloscope is supplanted by a wire array metamaterial. As the plasma frequency of a metamaterial is determined by its unit cell, and is thus a bulk property, a metamaterial resonator of any frequency can be made arbitrarily large, in contrast to a microwave cavity which incurs a steep penalty in volume with increasing frequency. We have investigated the basic properties of wire array metamaterials through $S_{21}$ measurements in the 10 GHz range. Excellent agreement with theoretical models is found, by which we project achievable quality factors to be of order $10^{4}$ in an actual axion search. Furthermore, schemes for tuning the array over a usable dynamic range ($30\%$ in frequency) appear practical from an engineering perspective., Comment: Published in Annalen der Physik

Published
2022

11. The Angell Plot from the Potential Energy Landscape Perspective

Author

Zhang, D. M., Sun, D. Y., and Gong, X. G.

Subjects
Condensed Matter - Materials Science, Condensed Matter - Soft Condensed Matter, Condensed Matter - Statistical Mechanics
Abstract

Within the scenario of the potential energy landscape (PEL), a thermodynamic model has been developed to uncover the physics behind the Angell plot. In our model, by separating the barrier distribution in PELs into a Gaussian-like and a power-law form, we obtain a general relationship between the relaxation time and the temperature. The wide range of the experimental data in the Angell plot, as well as the molecular-dynamics data, can be excellently fitted by two characteristic parameters, the effective barrier ({\omega}) and the effective width ({\sigma}) of a Gaussian-like distribution. More importantly, the fitted {\omega} and {\sigma}^2 for all glasses are found to have a simple linear relationship within a very narrow band, and fragile and strong glasses are well separated in the {\omega}-{\sigma}^2 plot, which indicates that glassy states only appear in a specific region of the PEL.

Published
2022
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12. A Generic Solution of Fermion Sign Problem

Author

Wang, J. and Sun, D. Y.

Subjects
Physics - Computational Physics, Condensed Matter - Strongly Correlated Electrons
Abstract

The fermion sign problem, the biggest obstacle in quantum Monte Carlo calculations, is completely solved in this paper. Here, we find a strategy, in which the contribution from those negative-weighted paths is thoroughly cancelled or replaced by some positive-weighted paths. The crucial point lies on the Feynman path integral formula proposed in our group, which allows us to deeply analyze the Boltzmann weight of each path. Through mathematical proof, we demonstrate that physical quantities can be exactly calculated within a specific kind of paths, which have positive the Boltzmann weight. With this finding, a new Monte Carlo method is proposed, in which the fermion sign problem is absent. As an example, the current method is applied to the two-dimensional Hubbard model, and the results do manifest the correctness., Comment: 24 pages, 4 figures

Published
2022

14. A Comparison of Adjustable Positioning and Free Positioning After Pars Plana Vitrectomy for Rhegmatogenous Retinal Detachment: A Prospective Randomized Controlled Study

Author

Liang Q, Sun D, Xue S, Li X, Liu X, Du Q, Zhang Z, Ma X, and Li J

Subjects
rhegmatogenous retinal detachment, pars plana vitrectomy, adjustable positioning, free positioning, Ophthalmology, RE1-994
Abstract

Qianqian Liang,1– 3 Difang Sun,1– 3 Shuyue Xue,1– 3 Xinying Li,1– 3 Xin Liu,1– 3 Qing Du,1– 3 Zhichun Zhang,1– 3 Xiubin Ma,1– 3 Jun Li1– 3 1Eye Institute of Shandong First Medical University, Qingdao Eye Hospital of Shandong First Medical University, Qingdao, Shandong, People’s Republic of China; 2State Key Laboratory Cultivation Base, Shandong Provincial Key Laboratory of Ophthalmology, Qingdao, Shandong, People’s Republic of China; 3School of Ophthalmology, Shandong First Medical University, Qingdao, Shandong, People’s Republic of ChinaCorrespondence: Jun Li; Xiubin Ma, Eye Institute of Shandong First Medical University, Qingdao Eye Hospital of Shandong First Medical University, Qingdao, 266071, People’s Republic of China, Tel +86-532-85876380, Email doctor_li@126.com; maxiubin2005@126.comPurpose: To compare the effectiveness and safety of adjustable and free postoperative positioning after pars plana vitrectomy (PPV) for rhegmatogenous retinal detachment (RRD).Design: Prospective, randomized controlled study.Methods: A total of 94 eyes with RRD were enrolled from April 2020 to April 2023 and monitored postoperatively for at least 3 months. All patients underwent PPV combined with silicone oil injection or gas tamponade and were randomly divided postoperatively into two groups: an adjustable positioning group and a free positioning group. The success of the outcome was based on the retinal reattachment rate, best corrected visual acuity (BCVA), postoperative complications, and ocular biometric parameters such as anterior chamber depth (ACD) and lens thickness (LT).Results: The initial retinal reattachment rate was 97.9% in the adjustable positioning group and 95.7% in the free positioning group, manifesting no statistical difference between the two groups. Similarly, no statistical difference was observed between the two groups in the final BCVA, which was significantly improved compared to the preoperative BCVA. The comparison of the 1-month postoperative ACD and LT with the preoperative values showed no statistically significant differences in the two groups. The rates of complications were not statistically different in the two groups.Conclusion: After treating RRD using PPV, neither the adjustable nor the free postoperative positioning affected the retinal reattachment rate or the incidence of complications. Therefore, our study showed that it is safe and effective to adopt free positioning postoperatively, which may provide more options for patients with RRD undergoing PPV.Keywords: rhegmatogenous retinal detachment, pars plana vitrectomy, adjustable positioning, free positioning

Published
2023

15. LCLS-II-HE verification cryomodule high gradient performance and quench behavior

Author

Posen, S., Cravatta, A., Checchin, M., Aderhold, S., Adolphsen, C., Arkan, T., Bafia, D., Benwell, A., Bice, D., Chase, B., Contreras-Martinez, C., Dootlittle, L., Fuerst, J., Gonnella, D., Grassellino, A., Grimm, C., Hansen, B., Harms, E., Hartsell, B., Hays, G., Holzbauer, J., Hoobler, S., Kaluzny, J., Khabiboulline, T., Kucera, M., Lambert, D., Legg, R., Lewis, F., Makara, J., Maniar, H., Maniscalco, J. T., Martinello, M., Nelson, J., Paiagua, S., Pischalnikov, Y., Prieto, P., Reid, J., Ross, M., Serrano, C., Solyak, N., Syed, A., Sun, D., Tatkowski, G., Wang, R., White, M., and Zacarias, L.

Subjects
Physics - Accelerator Physics
Abstract

An 8-cavity, 1.3 GHz, LCLS-II-HE cryomodule was assembled and tested at Fermilab to verify performance before the start of production. Its cavities were processed with a novel nitrogen doping treatment to improve gradient performance. The cryomodule was tested with a modified protocol to process sporadic quenches, which were observed in LCLS-II production cryomodules and are attributed to multipacting. Dedicated vertical test experiments support the attribution to multipacting. The verification cryomodule achieved an acceleration voltage of 200 MV in continuous wave mode, corresponding to an average accelerating gradient of 24.1 MV/m, significantly exceeding the specification of 173 MV. The average Q0 (3.0x10^10) also exceeded its specification (2.7x10^10). After processing, no field emission was observed up to the maximum gradient of each cavity. This paper reviews the cryomodule performance and discusses operational issues and mitigations implemented during the several month program., Comment: 15 pages, 24 figures

Published
2021

16. Efficient World-line-based Quantum Monte Carlo Method Without Hubbard-Stratonovich Transformation

Author

Wang, J., Pan, W., and Sun, D. Y.

Subjects
Condensed Matter - Strongly Correlated Electrons, Condensed Matter - Statistical Mechanics, Physics - Computational Physics
Abstract

By precisely writing down the matrix element of the local Boltzmann operator, we have proposed a new path integral formulation for quantum field theory and developed a corresponding Monte Carlo algorithm. With current formula, the Hubbard-Stratonovich transformation is not necessary, and is not based on the determinant approach, which can improve the computational efficiency. The results show that, the simulation time has the square-law scaling with system sizes, which is comparable with the usual first-principle calculation. The current formula also improves the accuracy of the Suzuki-Trotter decomposition. As an example, we have studied the one-dimensional half-filled Hubbard model at finite temperature. The obtained results are in excellent agreement with the known solutions. The new formula and Monte Carlo algorithm can be used in various studies., Comment: 19 pages, 6 figures

Published
2021

18. High gradient performance and quench behavior of a verification cryomodule for a high energy continuous wave linear accelerator

Author

Posen, S, Cravatta, A, Checchin, M, Aderhold, S, Adolphsen, C, Arkan, T, Bafia, D, Benwell, A, Bice, D, Chase, B, Contreras-Martinez, C, Doolittle, L, Fuerst, J, Gonnella, D, Grassellino, A, Grimm, C, Hansen, B, Harms, E, Hartsell, B, Hays, G, Holzbauer, J, Hoobler, S, Kaluzny, J, Khabiboulline, T, Kucera, M, Lambert, D, Legg, R, Lewis, F, Makara, J, Maniar, H, Maniscalco, JT, Martinello, M, Nelson, J, Paiagua, S, Pischalnikov, Y, Prieto, P, Reid, J, Ross, M, Serrano, C, Solyak, N, Syed, A, Sun, D, Tatkowski, G, Wang, R, White, M, and Zacarias, L

Subjects
Physical Sciences, Nuclear & Particles Physics
Abstract

An eight-cavity, 1.3 GHz, SLAC linac coherent light source II High Energy cryomodule was assembled and tested at Fermilab to verify performance before the start of production. Its cavities were processed with a novel nitrogen doping treatment to improve gradient performance. The cryomodule was tested with a modified protocol to process sporadic quenches, which were observed in Linac Coherent Light Source II production cryomodules and are attributed to multipacting. Dedicated vertical test experiments support the attribution to multipacting. The verification cryomodule achieved an acceleration voltage of 200 MV in continuous wave mode, corresponding to an average accelerating gradient of 24.1 MV/m, significantly exceeding the specification of 173 MV. The average Q0 (3.0×1010) also exceeded its specification (2.7×1010). After processing, no field emission was observed up to the maximum gradient of each cavity. This paper reviews the cryomodule performance and discusses operational issues and mitigations implemented during the several month program.

Published
2022

19. Discovery of a paired Gaussian and long-tailed distribution of potential energies in nanoglasses

Author

Zhang, D. M., Sun, D. Y., and Gong, X. G.

Subjects
Condensed Matter - Soft Condensed Matter, Condensed Matter - Statistical Mechanics
Abstract

It is generally believed that the intrinsic properties of glasses are intimately related to potential-energy landscapes (PELs). However, little is known about the PELs of glasses below the glass transition temperature (Tg). Taking advantage of lower potential-energy barriers in nanosystems, we have systematically investigated the dynamics behavior of two nanoglasses, Al43 and Al46. Structure transformation is identified in our pure molecular-dynamics simulation far below Tg, which manifests the existence of metabasins in PELs, at least for nanoglasses. Surprisingly, we find that the distribution of potential energies shows a paired Gaussian and long-tailed distribution at temperatures below and approaching Tg; correspondingly, the distribution of the {\alpha}-relaxation time exhibits an exponential-like decay. In contrast to the Gaussian distribution of energy in typical liquids and solids, the unexpected distribution may reflect the intrinsic feature of nanoglasses. Associated with the exponential-like distribution of the {\alpha}-relaxation time, the stretched-exponential structural relaxation is found, and the maximum stretched behavior appears around Tg. Despite our studies focused on nanoglasses, the current finding may shed light on future studies of bulk glasses., Comment: 23 pages, 10 figures

Published
2021
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20. First demonstration of in-beam performance of bent Monolithic Active Pixel Sensors

Author

project, ALICE ITS, Rinella, G. Aglieri, Agnello, M., Alessandro, B., Agnese, F., Akram, R. S., Alme, J., Anderssen, E., Andreou, D., Antinori, F., Apadula, N., Atkinson, P., Baccomi, R., Badalà, A., Balbino, A., Bartels, C., Barthel, R., Baruffaldi, F., Belikov, I., Beole, S., Becht, P., Bhatti, A., Bhopal, M., Bianchi, N., Blidaru, M. B., Boca, G., Bok, J., Bonomi, G., Bonora, M., Borri, M., Borshchov, V., Botta, E., Bruno, G. E., Buckland, M., Bufalino, S., Cai, M., Camerini, P., Cariola, P., Catalano, F., Sanchez, C. Ceballos, Chakaberia, I., Chartier, M., Colamaria, F., Colella, D., Collu, A., Concas, M., Contin, G., Costanza, S., Cui, P., Dainese, A., Dainton, J. B., De Cilladi, L., De Martin, C., De Robertis, G., Deng, W., Di Mauro, A., Ding, Y., Durkac, M., Elia, D., Ersdal, M. R., Faggin, M., Fan, F., Fantoni, A., Fecchio, P., Feliciello, A., Feofilov, G., Ferk, A., Ferencei, J., Fiorenza, G., Flores, A. N., Fragiacomo, E., Gajanana, D., Gal, A., Gao, C., Gargiulo, C., Gianotti, P., Giubilato, P., Grant, A., Greiner, L., Grelli, A., Groettvik, O. S., Grosa, F., Hu, C. Guo, Hannigan, R., Hasenbichler, J. A., Helstrup, H., Hillemanns, H., Hills, C., Hindley, P., Hippolyte, B., Hofman, B., Hong, G. H., Huang, G., Iddon, J. P., Ilyas, H., Imhoff, M. A., Isakov, A., Jadlovska, A., Jadlovska, S., Jadlovsky, J., Jaelani, S., Johnson, T., Junique, A., Kalinak, P., Kalweit, A., Keil, M., Khabanova, Z., Khan, H., Kim, B., Kim, C., Kim, J., Kim, T., Klein, J., Kluge, A., Kobdaj, C., Kotliarov, A., Králik, I., Krizek, F., Kugathasan, T., Kuhn, C., Kuijer, P. G., Kushpil, S., Kweon, M. J., Kwon, J. Y., Kwon, Y., La Rocca, P., Lakrathok, A., Langoy, R., Larionov, P., Laudi, E., Lazareva, T., Lea, R., Lemmon, R. C., Li, X. L., Lien, J., Lim, B., Lim, S. H., Lindsay, S., Liu, A., Liu, J., Lunardon, M., Luparello, G., Lupi, M., Mager, M., Maire, A., Malik, Q. W., Mandaglio, G., Manzari, V., Mao, Y., Margagliotti, G. V., Markert, C., Marras, D., Martinengo, P., Masciocchi, S., Masera, M., Masoni, A., Mastroserio, A., Matuoka, P. F. T., Mazza, G., Mazzaschi, F., Mazzoni, M. A., Morel, F, Muccifora, V., Mulliri, A., Musa, L., Nesbo, S. V., Nesterov, D., Norman, J., Park, J., Patra, R. N, Pastore, C., Pei, H., Peng, X., Piano, S., Pinto, C., Pisano, S., Politano, S., Prakasa, E., Prino, F., Protsenko, M., Puccio, M., Rachevski, A., Ramello, L., Rami, F., Ravasenga, I., Rehman, A., Reidt, F., Riggi, F., Røed, K., Röhrich, D., Ronchetti, F., Rosano, A., Rossewij, M. J., Rossi, A., Rui, R., Russo, R., Sadikin, R., Sarritzu, V., Schambach, J., Senyukov, S., Seo, J. J., Shahoyan, R., Shaukat, S., Siddhanta, S., Sitta, M., Snellings, R. J. M., Snoeys, W., Songmoolnak, A., Sonneveld, J., Soramel, F., Suljic, M., Sumowidagdo, S., Sun, D., Sun, X., Tambave, G. J., Tersimonov, G., Tkacik, M., Toppi, M., Trifiró, A., Trogolo, S., Trubnikov, V., Turrisi, R., Tveter, T. S., Tymchuck, I., Ullaland, K., Urioni, M., Usai, G. L., Valle, N., van Doremalen, L. V. R., Vanat, T., Van Hoorne, J. W., Varga-Kofarago, M., Velure, A., Wang, D., Wang, Y., Wikne, J., Wright, J. R., Xu, R., Yang, P., Yin, Z., Yoo, I. -K., Yoon, J. H., Yuan, S., Zaccolo, V., Zhang, E., Zhang, X., Zherebchevskii, V., Zhou, D., Zhu, J., Zhu, Y., Zinovjev, G., and Zurlo, N.

Subjects
Physics - Instrumentation and Detectors
Abstract

A novel approach for designing the next generation of vertex detectors foresees to employ wafer-scale sensors that can be bent to truly cylindrical geometries after thinning them to thicknesses of 20-40$\mu$m. To solidify this concept, the feasibility of operating bent MAPS was demonstrated using 1.5$\times$3cm ALPIDE chips. Already with their thickness of 50$\mu$m, they can be successfully bent to radii of about 2cm without any signs of mechanical or electrical damage. During a subsequent characterisation using a 5.4GeV electron beam, it was further confirmed that they preserve their full electrical functionality as well as particle detection performance. In this article, the bending procedure and the setup used for characterisation are detailed. Furthermore, the analysis of the beam test, including the measurement of the detection efficiency as a function of beam position and local inclination angle, is discussed. The results show that the sensors maintain their excellent performance after bending to radii of 2cm, with detection efficiencies above 99.9% at typical operating conditions, paving the way towards a new class of detectors with unprecedented low material budget and ideal geometrical properties.

Published
2021

21. Alopecia Universalis in an Elderly Chinese Man Induced by Sacubitril/Alisartan, a Novel Angiotensin Receptor-Neprilysin Inhibitor

Author

Teng Y, Fan Y, Shang D, Tao X, and Sun D

Subjects
alopecia universalis, sacubitril/alisartan, angiotensin receptor-neprilysin inhibitor, Pathology, RB1-214, Therapeutics. Pharmacology, RM1-950
Abstract

Yan Teng,1 Yibin Fan,1 Danying Shang,1 Xiaohua Tao,1,&ast; Dongsheng Sun2,&ast; 1Center for Plastic & Reconstructive Surgery, Department of Dermatology, Zhejiang Provincial People’s Hospital, People’s Hospital of Hangzhou Medical College, Hangzhou, 310014, People’s Republic of China; 2Geriatric Medicine Center, Department of Geriatric Medicine, Zhejiang Provincial People’s Hospital (Affiliated People’s Hospital), Hangzhou Medical College, Hangzhou, Zhejiang, People’s Republic of China&ast;These authors contributed equally to this workCorrespondence: Dongsheng Sun, Geriatric Medicine Center, Department of Geriatric Medicine, Zhejiang Provincial People’s Hospital (Affiliated People’s Hospital), Hangzhou Medical College, Hangzhou, Zhejiang, People’s Republic of China, Email sunds@163.com Xiaohua Tao, Center for Plastic & Reconstructive Surgery, Department of Dermatology, Zhejiang Provincial People’s Hospital, People’s Hospital of Hangzhou Medical College, Hangzhou, 310014, People’s Republic of China, Email taoxiaohua@hmc.edu.cnAbstract: Drug-induced alopecia areata is a rare adverse event wherein medications such as antimicrobials, anticonvulsants, and biologics, trigger the premature transition of actively growing hairs into the telogen phase. Herein, a unique case of alopecia universalis observed during a clinical trial involving sacubitril/alisartan, a novel angiotensin receptor-neprilysin inhibitor (ARNI) has been reported. This case contributes to the range of cutaneous reactions that might be observed in association with ARNI therapy.Keywords: alopecia universalis, sacubitril/alisartan, angiotensin receptor-neprilysin inhibitor

Published
2023

24. Quantum engineering with hybrid magnonics systems and materials

Author

Awschalom, D. D., Du, C. H. R., He, R., Heremans, F. J., Hoffmann, A., Hou, J. T., Kurebayashi, H., Li, Y., Liu, L., Novosad, V., Sklenar, J., Sullivan, S. E., Sun, D., Tang, H., Tiberkevich, V., Trevillian, C., Tsen, A. W., Weiss, L. R., Zhang, W., Zhang, X., Zhao, L., and Zollitsch, C. W.

Subjects
Condensed Matter - Mesoscale and Nanoscale Physics, Condensed Matter - Materials Science, Quantum Physics
Abstract

Quantum technology has made tremendous strides over the past two decades with remarkable advances in materials engineering, circuit design and dynamic operation. In particular, the integration of different quantum modules has benefited from hybrid quantum systems, which provide an important pathway for harnessing the different natural advantages of complementary quantum systems and for engineering new functionalities. This review focuses on the current frontiers with respect to utilizing magnetic excitatons or magnons for novel quantum functionality. Magnons are the fundamental excitations of magnetically ordered solid-state materials and provide great tunability and flexibility for interacting with various quantum modules for integration in diverse quantum systems. The concomitant rich variety of physics and material selections enable exploration of novel quantum phenomena in materials science and engineering. In addition, the relative ease of generating strong coupling and forming hybrid dynamic systems with other excitations makes hybrid magnonics a unique platform for quantum engineering. We start our discussion with circuit-based hybrid magnonic systems, which are coupled with microwave photons and acoustic phonons. Subsequently, we are focusing on the recent progress of magnon-magnon coupling within confined magnetic systems. Next we highlight new opportunities for understanding the interactions between magnons and nitrogen-vacancy centers for quantum sensing and implementing quantum interconnects. Lastly, we focus on the spin excitations and magnon spectra of novel quantum materials investigated with advanced optical characterization., Comment: 36 pages, 16 figures

Published
2021

25. Linear magnetoresistance with a universal energy scale in a strong-coupling superconductor

Author

Zhang, W., Hu, Y. J., Kuo, C. N., Kuo, S. T., Fang, Yue-Wen, Lai, Kwing To, Liu, X. Y., Yip, K. Y., Sun, D., Balakirev, F. F., Lue, C. S., Chen, Hanghui, and Goh, Swee K.

Subjects
Condensed Matter - Superconductivity, Condensed Matter - Strongly Correlated Electrons
Abstract

The recent discovery of a nonsaturating linear magnetoresistance in several correlated electron systems near a quantum critical point has revealed an interesting interplay between the linear magnetoresistance and the zero-field linear-in-temperature resistivity. These studies suggest a possible role of quantum criticality on the observed linear magnetoresistance. Here, we report our discovery of a nonsaturating, linear magnetoresistance in Mo$_8$Ga$_{41}$, a nearly isotropic strong electron-phonon coupling superconductor with a linear-in-temperature resistivity from the transition temperature to $\sim$55 K. The growth of the resistivity in field is comparable to that in temperature, provided that both quantities are measured in the energy unit. Our datasets are remarkably similar to magnetoresistance data of the optimally doped La$_{2-x}$Sr$_x$CuO$_4$, despite the clearly different crystal and electronic structures, and the apparent absence of quantum critical physics in Mo$_8$Ga$_{41}$. A new empirical scaling formula is developed, which is able to capture the key features of the low-temperature magnetoresistance data of Mo$_8$Ga$_{41}$, as well as the data of La$_{2-x}$Sr$_x$CuO$_4$., Comment: 7 pages, 3 figures

Published
2020
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26. HucMSC-Exo Promote Mucosal Healing in Experimental Colitis by Accelerating Intestinal Stem Cells and Epithelium Regeneration via Wnt Signaling Pathway

Author

Liang X, Li C, Song J, Liu A, Wang C, Wang W, Kang Y, Sun D, Qian J, and Zhang X

Subjects
inflammatory bowel disease, mesenchymal stem cells, exosome, mucosal healing, wnt/β-catenin signaling pathway, Medicine (General), R5-920
Abstract

Xiaonan Liang,1,&ast; Chenyang Li,1,&ast; Jia Song,1 Airu Liu,1 Chen Wang,1 Wenxin Wang,1 Yaxing Kang,1,2 Donglei Sun,1 Jiaming Qian,1,3 Xiaolan Zhang1 1Department of Gastroenterology, The Second Hospital of Hebei Medical University, Hebei Key Laboratory of Gastroenterology, Hebei Institute of Gastroenterology, Hebei Clinical Research Center for Digestive Diseases, Shijiazhuang, Hebei, People’s Republic of China; 2Department of Endocrinology, The Second Hospital of Hebei Medical University, Shijiazhuang, Hebei, People’s Republic of China; 3Department of Gastroenterology, Peking Union Medical College Hospital, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing, People’s Republic of China&ast;These authors contributed equally to this workCorrespondence: Xiaolan Zhang, Department of Gastroenterology, The Second Hospital of Hebei Medical University, No. 215 Heping West Road, Shijiazhuang, Hebei, 050000, People’s Republic of China, Tel +86 0311-66007370, Email xiaolanzh@hebmu.edu.cn Jiaming Qian, Department of Gastroenterology, Peking Union Medical College Hospital, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing, 100730, People’s Republic of China, Tel +86 010-69158100, Email qianjiaming1957@126.comBackground: Mucosal healing has emerged as a crucial therapeutic goal for inflammatory bowel diseases (IBD). Exosomes (Exo) as a potential acellular candidate for stem cell therapy might be competent to promote mucosal healing, while its mechanism remains unexplored.Methods: Exosomes derived from human umbilical cord mesenchymal stem cells (hucMSCs) were subjected to experimental colitis mice intraperitoneally to estimate the role in mucosal healing and the regeneration of intestinal stem cells (ISCs) and epithelium. The intestinal organoid model of IBD was constructed utilizing tumor necrosis factor (TNF)-α for subsequent function analysis in vitro. Transcriptome sequencing was performed to decipher the underlying mechanism and Wnt-C59, an oral Wnt inhibitor, was used to confirm that further. Finally, the potential specific components of hucMSC‑exo were investigated based on several existing miRNA expression datasets.Results: HucMSC-exo showed striking potential for mucosal healing in colitis mice, characterized by decreased histopathological injuries and neutrophil infiltration as well as improved epithelial integrity. HucMSC-exo up-regulated the expression of leucine-rich repeat-containing G-protein coupled receptor 5 (Lgr5), a specific marker for ISCs and accelerated the proliferation of intestinal epithelium. HucMSC-exo endowed intestinal organoids with more excellent capacity to grow and bud under TNF-α stimulation. More than that, the fact that hucMSC-exo activated the canonical Wnt signaling pathway to promote mucosal healing was uncovered by not only RNA-sequencing but also relevant experimental data. Finally, bioinformatics analysis of the existing miRNA expression datasets indicated that several miRNAs abundant in hucMSC-exo involved widely in regeneration or repair related biological processes and Wnt signaling pathway might be one of the most important signal transduction pathways.Conclusion: Our results suggested that hucMSC-exo could facilitate mucosal healing in experimental colitis by accelerating ISCs and intestinal epithelium regeneration via transferring key miRNAs, which was dependent on the activation of Wnt/β-catenin signaling pathway.Keywords: inflammatory bowel disease, mesenchymal stem cells, exosome, mucosal healing, Wnt/β-catenin signaling pathway

Published
2023

27. Manipulating the Glass Transition in Nanoscale

Author

Sun, D. Y. and Gong, X. G.

Subjects
Condensed Matter - Soft Condensed Matter, Condensed Matter - Mesoscale and Nanoscale Physics
Abstract

The intrinsic nature of glass states or glass transitions has been a mystery for a long time. Recently, more and more studies tend to show that a glass locates at a specific potential energy landscape (PEL). To explore how the flatness of the PEL related to glass transition, we develop a method to adjust the PEL in a controllable manner. We demonstrate that a relatively flat PEL is not only necessary but also sufficient for the formation of a nanoscale glass. We show that: (1) as long as a nanocluster is located in a region of PEL with local minimum deep enough, it can undergo a first-order solid-liquid phase transition; and (2) if a nanocluster is located in a relatively flat PEL, it can undergo a glass transition. All these transitions are independent of its structure symmetry, order or disorder. Our simulations also uncover the direct transition from one potential energy minimum to another below the glass transition temperature, which is the consequence of flat PELs.

Published
2020
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28. Thank You to Our 2020 Peer Reviewers

Author

Rajaram, H, Camargo, S, Cappa, C, Carey, R, Cory, R, Dombard, A, Donohue, K, Flesch, L, Giannini, A, Gu, Y, Hayes, G, Hogg, A, Huber, C, Ivanov, V, Jacobsen, S, Korte, M, Lu, G, Morlighem, M, Magnusdottir, G, Opher, M, Patricola, C, Prieto, G, Qiu, B, Ritsema, J, Sprintall, J, Su, H, Sun, D, Thornton, J, Trouet, V, Wang, K, Whalen, C, White, A, and Yau, A

Subjects
Meteorology & Atmospheric Sciences
Published
2021

30. Identification of non-Hodgkin lymphoma patients at risk for treatment-related vertebral density loss and fractures

Author

Bodden, J, Sun, D, Joseph, GB, Huang, L-W, Andreadis, C, Hughes-Fulford, M, Lang, TF, and Link, TM

Subjects
Osteoporosis, Rare Diseases, Cancer, Physical Injury - Accidents and Adverse Effects, Biomedical Imaging, Clinical Research, Hematology, Lymphoma, Prevention, Injuries and accidents, Musculoskeletal, Bone Density, Humans, Lumbar Vertebrae, Lymphoma, Non-Hodgkin, Osteoporotic Fractures, Spinal Fractures, Bone density, Computed tomography, Non-Hodgkin lymphoma, Screening, Biomedical Engineering, Clinical Sciences, Public Health and Health Services, Endocrinology & Metabolism
Abstract

Information on bone loss in treated non-Hodgkin's lymphoma patients is limited. In this study, we used CT to analyze bone loss as well as prevalent and incident fractures. We found severe bone loss, a high rate of fractures, and a novel association between bone loss and the international prognostic index.IntroductionTo investigate bone loss and fracture risk in non-Hodgkin-lymphoma (NHL) patients by (i) comparing treatment-related vertebral density (VD) loss in NHL patients with control subjects and (ii) investigating associations of VD loss versus fracture risk. Further, associations of VD loss and clinical parameters were investigated.MethodsVD of 123 NHL patients was measured pre- and post-treatment in the L1, L2, and L3 vertebrae in routine computed tomography (CT) scans, performed between Jan 2016 and Mar 2017. Control measurements (n = 52) were obtained from CT colonographies between Sept 2003 and Sept 2017 and their subsequent follow-up-exams (10-137 months). Prevalent and incident (between baseline and follow-up) fractures were assessed in all subjects, and VD loss per year was calculated. Linear regression models were used to (i) compare VD loss between patients and controls and (ii) identify associations between VD loss and clinical parameters. Using logistic regression models, ORs for fractures per SD change in VD were assessed in patients. Analyses were adjusted for age, sex, and contrast application.ResultsNHL patients experienced significantly greater VDL1-3 loss than controls (P = 0.003), and greater VDL1-3 loss was associated with a greater likelihood of incident fractures (OR, [95%-CI], P 1.90, [1.03, 3.51], 0.04). Patients with an initial international prognostic index (IPI) of 5 suffered significantly greater VD loss compared with an IPI of 0 (P = 0.01).ConclusionUsing VD measurements in routine CT scans, substantial vertebral bone loss in NHL patients could be documented with a high incidence of fractures.

Published
2021

31. Clinical Characteristics Combined with Craniofacial Photographic Analysis in Children with Obstructive Sleep Apnea

Author

Wang H, Xu W, Zhao A, Sun D, Li Y, and Han D

Subjects
obstructive sleep apnea, clinical features, photographic measurements, children, Psychiatry, RC435-571, Neurophysiology and neuropsychology, QP351-495
Abstract

Huijun Wang,1,2 Wen Xu,1,2 Anqi Zhao,1,2 Dance Sun,1,2 Yanru Li,1,2 Demin Han1,2 1Department of Otorhinolaryngology Head and Neck Surgery, Beijing Tongren Hospital, Capital Medical University, Beijing, People’s Republic of China; 2Key Laboratory of Otolaryngology-Head and Neck Surgery, Ministry of Education, Capital Medical University, Beijing, People’s Republic of ChinaCorrespondence: Demin Han; Yanru Li, Beijing Tongren Hospital, Capital Medical University, 1 Dongjiaominxiang, Dongcheng District, Beijing, People’s Republic of China, Email deminhan_ent@hotmail.com; liyanruru@aliyun.comPurpose: Distinguishing obstructive sleep apnea (OSA) in a high-risk population remains challenging. This study aimed to investigate clinical features to identify children with OSA combined with craniofacial photographic analysis.Methods: One hundred and forty-five children (30 controls, 62 with primary snoring, and 53 with OSA) were included. Differences in general demographic characteristics and surface facial morphology among the groups were compared. Risk factors and prediction models for determining the presence of OSA (obstructive sleep apnea-hypopnea index> 1) were developed using logistic regression analysis.Results: The BMI (z-score), tonsil hypertrophy, and lower face width (adjusted age, gender, and BMI z-score) were showed significantly different in children with OSA compared with primary snoring and controls (adjusted p< 0.05). The screening model based on clinical features and photography measurements correctly classified 79.3% of the children with 64.2% sensitivity and 89.1% specificity. The area under the curve of the model was 81.0 (95% CI, 73.5– 98.4%).Conclusion: A screening model based on clinical features and photography measurements would be helpful in clinical decision-making for children with highly suspected OSA if polysomnography remains inaccessible in resource-stretched healthcare systems.Keywords: obstructive sleep apnea, clinical features, photographic measurements, children

Published
2023

32. Netrin-1 Monoclonal Antibody-Functionalized Nanoparticle Loaded with Metformin Prevents the Progression of Abdominal Aortic Aneurysms

Author

Zhang Z, Zhuang J, Sun D, Ding Q, Zheng H, Li H, Zhang X, Du Y, Ma T, and Meng Q

Subjects
abdominal aortic aneurysm, nanoparticle, metformin, macrophage, Medicine (General), R5-920
Abstract

Zhiwei Zhang,1,&ast; Jiawei Zhuang,2,&ast; Daohan Sun,3,&ast; Qingwei Ding,1 Hui Zheng,1 Haixiang Li,1 Xiaoyu Zhang,1 Yaming Du,3 Teng Ma,1 Qingyou Meng1 1Department of Vascular Surgery, General Surgery Clinical Center, Shanghai General Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, People’s Republic of China; 2Department of Cardiovascular Surgery, The First Affiliated Hospital of Xiamen University, School of Medicine, Xiamen University, Xiamen, People’s Republic of China; 3Department of Vascular Surgery, The First Affiliated Hospital of Jinzhou Medical University, Jinzhou, People’s Republic of China&ast;These authors contributed equally to this workCorrespondence: Qingyou Meng; Teng Ma, Email mengqy@163.com; m_aeolus@163.comBackground: Abdominal aortic aneurysms (AAAs) are a global health and economic burden. Therapeutic strategies to inhibit the progression of AAAs are currently lacking. Recently, the therapeutic effect of metformin on aneurysms has attracted considerable interest. However, the unfavorable pharmacokinetic properties of metformin limit its feasibility for AAA treatment.Methods and Results: We constructed a metformin-loaded netrin-1-responsive AAA-targeted nanoparticle (Tgt-NP-Met) for AAA management. Evaluation of the therapeutic effect of Tgt-NP-Met was performed by in vitro and in vivo experiments. Our results showed that the binding of netrin-1 monoclonal antibodies enhanced the AAA-targeting capability of nanoparticles (NPs). Moreover, Tgt-NP-Met administration prevented AAA development and reduced the aneurysm diameter in apolipoprotein E (ApoE)-deficient (ApoE−/−) mice that received continuous infusion of angiotensin II. Furthermore, metformin prevented AAA progression by inhibiting the transformation of vascular smooth muscle cells (VSMCs) from a contractile phenotype to a synthetic phenotype, which is mediated by macrophage infiltration and activation.Conclusion: Our findings identify metformin as a functional suppressor for macrophage-mediated phenotypic transformation of VSMCs and Tgt-NP-Met as an efficient therapeutic strategy for AAA management.Graphical Abstract: Keywords: abdominal aortic aneurysm, nanoparticle, metformin, macrophage

Published
2023

34. Detection of hole pockets in the candidate type-II Weyl semimetal MoTe$_2$ from Shubnikov-de Haas quantum oscillations

Author

Hu, Y. J., Yu, W. C., Lai, Kwing To, Sun, D., Balakirev, F. F., Zhang, W., Xie, J. Y., Yip, K. Y., Aulestia, E. I. Paredes, Jha, Rajveer, Higashinaka, Ryuji, Matsuda, Tatsuma D., Yanase, Y., Aoki, Yuji, and Goh, Swee K.

Subjects
Condensed Matter - Superconductivity, Condensed Matter - Materials Science
Abstract

The bulk electronic structure of $T_d$-MoTe$_2$ features large hole Fermi pockets at the Brillouin zone center ($\Gamma$) and two electron Fermi surfaces along the $\Gamma-X$ direction. However, the large hole pockets, whose existence has important implications for the Weyl physics of $T_d$-MoTe$_2$, has never been conclusively detected in quantum oscillations. This raises doubt about the realizability of Majorana states in $T_d$-MoTe$_2$, because these exotic states rely on the existence of Weyl points, which originated from the same band structure predicted by density functional theory (DFT). Here, we report an unambiguous detection of these elusive hole pockets via Shubnikov-de Haas (SdH) quantum oscillations. At ambient pressure, the quantum oscillation frequencies for these pockets are 988 T and 1513 T, when the magnetic field is applied along the $c$-axis. The quasiparticle effective masses $m^*$ associated with these frequencies are 1.50 $m_e$ and 2.77 $m_e$, respectively, indicating the importance of Coulomb interactions in this system. We further measure the SdH oscillations under pressure. At 13 kbar, we detected a peak at 1798 T with $m^*$ = 2.86 $m_e$. Relative to the oscillation data at a lower pressure, the amplitude of this peak experienced an enhancement, which can be attributed to the reduced curvature of the hole pockets under pressure. Combining our experimental data with DFT + $U$ calculations, where $U$ is the Hubbard parameter, our results shed light on why these important hole pockets have not been detected until now., Comment: 6 pages, 4 figures. Revised author list. Phys. Rev. Lett. (in press)

Published
2019
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35. Nonsaturating large magnetoresistance in the high carrier density nonsymmorphic metal CrP

Author

Niu, Q., Yu, W. C., Aulestia, E. I. Paredes, Hu, Y. J., Lai, Kwing To, Kotegawa, H., Matsuoka, E., Sugawara, H., Tou, H., Sun, D., Balakirev, F. F., Yanase, Y., and Goh, Swee K.

Subjects
Condensed Matter - Strongly Correlated Electrons, Condensed Matter - Materials Science
Abstract

The band structure of high carrier density metal CrP features an interesting crossing at the Y point of the Brillouin zone. The crossing, which is protected by the nonsymmorphic symmetry of the space group, results in a hybrid, semi-Dirac-like energy-momentum dispersion relation near Y. The linear energy-momentum dispersion relation along Y-$\Gamma$ is reminiscent of the observed band structure in several semimetallic extremely large magnetoresistance (XMR) materials. We have measured the transverse magnetoresistance of CrP up to 14 T at temperatures as low as $\sim$ 16 mK. Our data reveal a nonsaturating, quadratic magnetoresistance as well as the behaviour of the so-called `turn-on' temperature in the temperature dependence of resistivity. Despite the difference in the magnitude of the magnetoresistance and the fact that CrP is not a semimetal, these features are qualitatively similar to the observations reported for XMR materials. Thus, the high-field electrical transport studies of CrP offer the prospect of identifying the possible origin of the nonsaturating, quadratic magnetoresistance observed in a wide range of metals., Comment: 6 pages. Phys. Rev. B (in press)

Published
2019
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36. Reply to Comment on Optical detection of transverse spin-Seebeck effect in permalloy film using Sagnac interferometer microscopy (arXiv:1810.13220)

Author

McLaughlin, R., Sun, D., Zhang, C., Groesbeck, M., and Vardeny, Z. Valy

Subjects
Condensed Matter - Materials Science
Abstract

In their Comment, Kimling and Kuschel (hereafter the commenters) challenge our original interpretation of the magneto-optical Kerr effect (MOKE) measurements using ultrasensitive Sagnac interferometer, claiming that the transverse spin-Seebeck effect (TSSE) is not the only contribution to the measured change in the Kerr rotation angle from a Ni80Fe20 (NiFe) ferromagnetic (FM) slab subjected to a lateral temperature gradient in the presence of a magnetic field. The authors assert that: (1) the TSSE, in general, has not been completely proven so far, and that the existing theories, in particular the phonon magnon drag model that we have used in our publication, in fact cannot explain the original work of Uchida et al. (2) The commenters based their critique on an estimate of the magnitude of the measured effect, arguing that to observe the TSSE that we originally claimed, the temperature gradient in our measurements should have been much larger than the value we measured. In this Reply, firstly, we summarize previous literature reports on the TSSE response in FM metallic systems. Secondly, we dispute the estimate of the necessary large temperature gradient made by the commenters. Importantly, the Kerr effect sensitivity to spin accumulation (via the TSSE response) has not been recognized by the commenters, in fact it was mistakenly assumed that the Kerr effect sensitivity to the spin accumulation by the TSSE is the same as the Kerr sensitivity to the bulk magnetization change due to the temperature change. In conclusion, we show that the TSSE is the only viable interpretation of our original measurements, and that the phonon-magnon drag model is indeed capable of explaining our results.

Published
2018
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37. High lithium sulfide loading electrodes for practical Li/S cells with high specific energy

Author

Sun, D, Hwa, Y, Zhang, L, Xiang, J, Guo, J, Huang, Y, and Cairns, EJ

Subjects
Lithium/sulfur cell, Lithium sulfide, High loading, Electrolyte/sulfur ratio, Aluminum foam current collector, Macromolecular and Materials Chemistry, Materials Engineering, Nanotechnology
Abstract

To date, Li2S has drawn significant attention as a positive electrode active material for rechargeable lithium cells due to its high theoretical specific capacity and capability of pairing with a lithium-free anode which can obviate any safety concern of the lithium metal anode when using sulfur. In recent years, various approaches have been employed to develop Li/Li2S rechargeable cells for commercialization that meet the performance goals for high energy/power applications. It is expected that high lithium sulfide-loading cells with long cycle life, an excellent capacity delivery and low electrolyte:sulfur weight ratio (E/S ratio) can be achieved. Here, we report a Li2S electrode comprised of a novel Li2S/KB@Cf nanocomposite which delivers an areal capacity of 7.56 mAh cm-2 and good cycling stability with a mass loading of 11.29 mg cm-2 and a robust 3-dimensional (3D) aluminum foam current collector with a high open area. The high conductivity and scalability of the active material, the availability of 3D current collection for the active material and the control of the electrolyte/sulfur ratio offer the potential of realization of practical Li/S cells.

Published
2019

38. Explosive fragmentation of additively manufactured stainless steel.

Author

Callahan, M., Sun, D., Linne, M. A., Wu, A. S., Campbell, G. H., Friedman, B., Rodriguez, J., Burke, S., Lodes, A., Hansen, K., Mickelson, K., Wraith, R., Nicolino, J. J., and Park, H.-S.

Subjects
*STAINLESS steel, *STEEL manufacture, *DOPPLER velocimetry, *STRAINS & stresses (Mechanics), *STRESS concentration
Abstract

Properties of fragmentation from an explosively driven 316L stainless steel spherical shell section fabricated by a laser powder bed additive manufacturing process with minimal surface finishing are investigated. This shell is driven by an insensitive high explosive, resulting in high strain rate deformation (>8 × 103 s−1) and failure of the stainless steel. Photonic Doppler velocimetry measures the expansion rate; dynamic radiography and high-speed imaging capture the fracture behavior of the stainless steel. The fracture response of the additively manufactured stainless steel shell is compared to published experimental results on additively manufactured 316L stainless steel and conventionally manufactured wrought 316L and 304 stainless steel shell fragmentation. Despite preferred crack orientation, suggesting the influence of surface grooves on fracture time, fragment size is identical to that measured in a similar experiment on wrought 304 stainless steel. Further analysis indicates that the 316L additively manufactured stainless steel shell exhibits comparable spall strength and fragmentation toughness to conventionally manufactured stainless steel yet lower failure strain due to surface stress concentrations. [ABSTRACT FROM AUTHOR]

Published
2023
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39. Recent Advances in Nanozymes for Bacteria-Infected Wound Therapy

Author

Mo F, Zhang M, Duan X, Lin C, Sun D, and You T

Subjects
nanozyme, wound healing, bacterial infections, antibacterial, antibiofilms, Medicine (General), R5-920
Abstract

Fayin Mo,1,2 Minjun Zhang,1 Xuewei Duan,1 Chuyan Lin,1 Duanping Sun,2,3 Tianhui You1 1School of Nursing, Guangdong Provincial Key Laboratory of Pharmaceutical Bioactive Substances, Guangdong Pharmaceutical University, Guangzhou, People’s Republic of China; 2Center for Drug Research and Development, Guangdong Provincial Key Laboratory of Pharmaceutical Bioactive Substances, Guangdong Pharmaceutical University, Guangzhou, People’s Republic of China; 3Key Specialty of Clinical Pharmacy, The First Affiliated Hospital of Guangdong Pharmaceutical University, Guangzhou, People’s Republic of ChinaCorrespondence: Duanping Sun; Tianhui You, Email sundp@gdpu.edu.cn; youth888cn@aliyun.comAbstract: Bacterial-infected wounds are a serious threat to public health. Bacterial invasion can easily delay the wound healing process and even cause more serious damage. Therefore, effective new methods or drugs are needed to treat wounds. Nanozyme is an artificial enzyme that mimics the activity of a natural enzyme, and a substitute for natural enzymes by mimicking the coordination environment of the catalytic site. Due to the numerous excellent properties of nanozymes, the generation of drug-resistant bacteria can be avoided while treating bacterial infection wounds by catalyzing the sterilization mechanism of generating reactive oxygen species (ROS). Notably, there are still some defects in the nanozyme antibacterial agents, and the design direction is to realize the multifunctionalization and intelligence of a single system. In this review, we first discuss the pathophysiology of bacteria infected wound healing, the formation of bacterial infection wounds, and the strategies for treating bacterially infected wounds. In addition, the antibacterial advantages and mechanism of nanozymes for bacteria-infected wounds are also described. Importantly, a series of nanomaterials based on nanozyme synthesis for the treatment of infected wounds are emphasized. Finally, the challenges and prospects of nanozymes for treating bacterial infection wounds are proposed for future research in this field.Graphical Abstract: Keywords: nanozyme, wound healing, bacterial infections, antibacterial, antibiofilms

Published
2022

40. Evaluation of Risk Factors for Chronic Obstructive Pulmonary Disease in the Middle-Aged and Elderly Rural Population of Northeast China Using Logistic Regression and Principal Component Analysis

Author

Wang R, Zhang W, Li Y, Jiang Y, Feng H, Du Y, Jiao Z, Lan L, Liu X, Li B, Liu C, Gu X, Chu F, Shen Y, Zhu C, Shao X, Tong S, and Sun D

Subjects
chronic obstructive pulmonary disease, collinearity, principal component, logistic regression, Public aspects of medicine, RA1-1270
Abstract

Rui Wang,1– 4 Wei Zhang,1– 3 Yuanyuan Li,1– 3 Yuting Jiang,1– 3 Hongqi Feng,1– 3 Yang Du,1– 3 Zhe Jiao,1– 3 Li Lan,4 Xiaona Liu,1– 3 Bingyun Li,1– 3 Chang Liu,1– 3 Xingbo Gu,5 Fang Chu,1– 3 Yuncheng Shen,1– 3 Chenpeng Zhu,1– 3 Xinhua Shao,1– 3 Simeng Tong,1– 3 Dianjun Sun1– 3 1Center for Endemic Disease Control, Chinese Center for Disease Control and Prevention, Harbin Medical University, Harbin, 150081, People’s Republic of China; 2National Health Commission & Education Bureau of Heilongjiang Province, Key Laboratory of Etiology and Epidemiology, Harbin Medical University (23618504), Harbin, 150081, People’s Republic of China; 3Heilongjiang Provincial Key Laboratory of Trace Elements and Human Health, Harbin Medical University, Harbin, 150081, People’s Republic of China; 4Harbin Center for Disease Control and Prevention, Harbin, 150056, People’s Republic of China; 5Department of Biostatistics, School of Public Health, Hainan Medical University, Haikou, 571199, People’s Republic of ChinaCorrespondence: Dianjun Sun, Center for Endemic Disease Control, Chinese Center for Disease Control and Prevention, Harbin Medical University, Baojian Road 157, Harbin, Heilongjiang Province, 150081, People’s Republic of China, Tel +86-13313685318, Fax +86 45186612695, Email hrbmusdj@163.comPurpose: To investigate the environmental, immune, and inflammatory factors associated with chronic obstructive pulmonary disease (COPD) in middle-aged and older Chinese individuals.Patients and Methods: A community-based case–control study was conducted among 471 patients with COPD and 485 controls. The information on COPD of the participants was collected through face-to-face interviews, and serum samples were measured at the laboratory. The main risk factors for COPD were analyzed using principal component analysis (PCA) and logistic regression.Results: Nine hundred and fifty-six respondents were included in the analysis. The results of the PCA-logistic regression analysis showed significant differences in the environmental factors, medical history, and serum C-reactive protein (CRP) levels between patients and controls. COPD was markedly more usual in those with smoking index > 200 (OR, 1.42; 95% CI, 1.28– 1.57); exposure to outdoor straw burning (OR, 1.64; 95% CI, 1.47– 1.83); use of coal, wood, and straw indoors (OR, 2.31; 95% CI, 1.92– 2.78); history of respiratory disease and coronary heart disease (OR, 3.58; 95% CI, 3.12– 4.10), congestive heart failure (OR, 1.23; 95% CI, 1.09– 1.38), and cerebrovascular disease (OR, 1.15; 95% CI,1.02– 1.31); and higher serum level of CRP (OR, 1.20; 95% CI, 1.11– 1.30). Compared to the logistic regression analysis, PCA logistic regression analysis identified more important risk factors for COPD.Conclusion: PCA-logistic regression analysis was first utilized to explore the influencing factors among rural residents in Northeast China Environmental aged 40 years and above, it was found that environmental factors, medical history, and serum CRP levels mainly affected the prevalence of COPD.Keywords: chronic obstructive pulmonary disease, collinearity, principal component, logistic regression

Published
2022

42. Early Human Lung Immune Cell Development and Its Role in Epithelial Cell Fate

Author

Nikolic, M., primary, Barnes, J.L., additional, Yoshida, M., additional, He, P., additional, Worlock, K.B., additional, Lindeboom, R.G.H., additional, Suo, C., additional, Pett, J.P., additional, Wilbrey-Clark, A., additional, Dann, E., additional, Mamanova, L., additional, Richardson, L., additional, Polanski, K., additional, Pennycuick, A., additional, Allen-Hyttinen, J., additional, Herczeg, I., additional, Arzili, R., additional, Hynds, R.E., additional, Teixeira, V.H., additional, Haniffa, M., additional, Lim, K., additional, Sun, D., additional, Rawlins, E.L., additional, Oliver, A., additional, Lyons, P.A., additional, Marioni, J.C., additional, Ruhrberg, C., additional, Tuong, Z.K., additional, Clatworthy, M.R., additional, Reading, J.L., additional, Janes, S.M., additional, Teichmann, S.A., additional, and Meyer, K.B., additional

Published
2024
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44. First observation of band structure in As76 : Possible chirality and octupole correlations

Author

Xu, W. Z., primary, Sun, D. P., additional, Wang, S. Y., additional, Bark, R. A., additional, Hua, H., additional, Meng, J., additional, Zhang, S. Q., additional, Jones, P., additional, Wyngaardt, S. M., additional, Liu, C., additional, Wang, S., additional, Li, G. Y., additional, Mu, L., additional, Bai, H. F., additional, Xiao, X., additional, Li, Z. Q., additional, Zhang, N. B., additional, Jia, H., additional, Guo, R. J., additional, Han, X. C., additional, Qi, B., additional, Niu, C. Y., additional, Wang, C. G., additional, Lawrie, E. A., additional, Lawrie, J. J., additional, Sharpey-Schafer, J. F., additional, Wiedeking, M., additional, Majola, S. N. T., additional, Bucher, T. D., additional, Dinoko, T., additional, Maqabuka, B., additional, Makhathini, L., additional, Mdletshe, L., additional, Khumalo, N. A., additional, Shirinda, O., additional, and Sowazi, K., additional

Published
2024
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45. The FNAL Booster 2nd Harmonic RF Cavity

Author

Madrak, R., Dey, J., Duel, K., Kufer, M., Kuharik, J., Makarov, A., Padilla, R., Pellico, W., Reid, J., Romanov, G., Slabaugh, M., Sun, D., Tan, C. Y., and Terechkine, I.

Subjects
Physics - Accelerator Physics
Abstract

A second harmonic RF cavity which uses perpendicularly biased garnet for frequency tuning is currently being constructed for use in the Fermilab Booster. The cavity will operate at twice the fundamental RF frequency, from ~76 - 106 MHz, and will be turned on only during injection, and transition or extraction. Its main purpose is to reduce beam loss as required by Fermilab's Proton Improvement Plan (PIP). After three years of optimization and study, the cavity design has been finalized and all constituent parts have been received. We discuss the design aspects of the cavity and its associated systems, component testing, and status of the cavity construction., Comment: 6 pp

Published
2018

46. Garnet Ring Measurements For The Fermilab Booster 2nd Harmonic Cavity

Author

Kuharik, J., Dey, J., Duel, K., Madrak, R., Makarov, A., Pellico, W., Reid, J., Romanov, G., Slabaugh, M., Sun, D., Tan, C. Y., and Terechkine, I.

Subjects
Physics - Accelerator Physics
Abstract

A perpendicularly biased tuneable 2nd harmonic cavity is being constructed for use in the Fermilab Booster. The cavity's tuner uses National Magnetics AL800 garnet as the tuning media. For quality control, the magnetic properties of the material and the uniformity of the properties within the tuner must be assessed. We describe two tests which are performed on the rings and on their corresponding witness samples., Comment: 3 pp

Published
2018

47. PIP-II Injector Test Warm Front End: Commissioning Update

Author

Prost, L., Andrews, R., Baffes, C., Carneiro, J. -P., Chase, B., Chen, A., Cullerton, E., Derwent, P. F., Edelen, J. P., Einstein-Curtis, J., Frolov, D., Hanna, B., Peterson, D., Saewert, G., Saini, A., Scarpine, V., Shemyakin, A., Steimel, J., Sun, D., Warner, A., Richard, C., and Sista, V. L. S.

Subjects
Physics - Accelerator Physics
Abstract

The Warm Front End (WFE) of the Proton Improvement Plan II Injector Test at Fermilab has been constructed to its full length. It includes a 15-mA DC, 30-keV H- ion source, a 2 m-long Low Energy Beam Transport (LEBT) with a switching dipole magnet, a 2.1 MeV CW RFQ, followed by a Medium Energy Beam Transport (MEBT) with various diagnostics and a dump. This report presents the commissioning status, focusing on beam measurements in the MEBT. In particular, a beam with the parameters required for injection into the Booster (5 mA, 0.55 ms macro-pulse at 20 Hz) was transported through the WFE., Comment: 4 pp

Published
2018

48. Commissioning And First Results From The Fermilab Cryomodule Test Stand

Author

Harms, E. R., Awida, M., Baffes, C., Carlson, K., Chandrasekaran, S., Chase, B., Cullerton, E., Edelen, J., Einstein-Curtis, J., Ginsburg, C., Grassellino, A., Hansen, B., Holzbauer, J., Kazakov, S., Khabiboulline, T., Kucera, M., Leibfritz, J., Lunin, A., McDowell, D., McGee, M., Nicklaus, D., Orris, D., Ozelis, J., Patrick, J., Petersen, T., Pischalnikov, Y., Prieto, P., Prokofiev, O., Reid, J., Schappert, W., Sergatskov, D., Solyak, N., Stanek, R., Sun, D., White, M., Worel, C., and Wu, G.

Subjects
Physics - Accelerator Physics
Abstract

A new test stand dedicated to Superconducting Radiofrequency (SRF) cryomodule testing, CMTS1, has been commissioned and is now in operation at Fermilab. The first device to be cooled down and powered in this facility is the prototype 1.3 GHz cryomodule assembled at Fermilab for LCLS-II. We describe the demonstrated capabilities of CMTS1, report on steps taken during commissioning, provide an overview of first test results, and survey future plans., Comment: 4 pp. Proceedings of LINAC2016, East Lansing, MI, USA

Published
2018

49. Status of the warm front end of PIP-II injector test

Author

Shemyakin, A., Alvarez, M., Andrews, R., Baffes, C., Carneiro, J. -P., Chen, A., Derwent, P. F., Edelen, J. P., Frolov, D., Hanna, B., Prost, L., Saini, A., Saewert, G., Scarpine, V., Sista, V. L. S., Steimel, J., Sun, D., and Warner, A.

Subjects
Physics - Accelerator Physics
Abstract

The Proton Improvement Plan II (PIP-II) at Fermilab is a program of upgrades to the injection complex. At its core is the design and construction of a CW compatible, pulsed H- SRF linac. To validate the concept of the front-end of such machine, a test accelerator known as PIP-II Injector Test (PIP2IT) is under construction. It includes a 10 mA DC, 30 keV H- ion source, a 2 m-long Low Energy Beam Transport (LEBT), a 2.1 MeV CWRFQ, followed by a Medium Energy Beam Transport (MEBT) that feeds the first of 2 cryomodules increasing the beam energy to about 25 MeV, and a High Energy Beam Transport section (HEBT) that takes the beam to a dump. The ion source, LEBT, RFQ, and initial version of the MEBT have been built, installed, and commissioned. This report presents the overall status of the warm front end., Comment: 4 pp. 8th International Particle Accelerator Conference (IPAC 2017) 14-19 May 2017. Copenhagen, Denmark

Published
2018

50. A unified framework for heat and mass transport at the atomic scale

Author

Ponga, M. and Sun, D.

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

We present a unified framework to simulate heat and mass transport in systems of particles. The proposed framework is based on kinematic mean field theory and uses a phenomenological master equation to compute effective transport rates between particles without the need to evaluate operators. We exploit this advantage and apply the model to simulate transport phenomena at the nanoscale. We demonstrate that, when calibrated to experimentally-measured transport coefficients, the model can accurately predict transient and steady state temperature and concentration profiles even in scenarios where the length of the device is comparable to the mean free path of the carriers. Through several example applications, we demonstrate the validity of our model for all classes of materials, including ones that, until now, would have been outside the domain of computational feasibility.

Published
2018
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