Undergraduate

Research Output 1973 2020

2019
Hematopoietic Stem Cell Transplantation
Metabolic Diseases
Lipodystrophy
Graft vs Host Disease
Fats

Acromegaly caused by a somatotroph adenoma in patient with neurofibromatosis type 1

Hozumi, K., Fukuoka, H., Odake, Y., Takeuchi, T., Uehara, T., Sato, T., Inoshita, N., Yoshida, K., Matsumoto, R., Bando, H., Hirota, Y., Iguchi, G., Taniguchi, M., Otsuki, N., Nishigori, C., Kosaki, K., Hasegawa, T., Ogawa, W. & Takahashi, Y., 2019 Jan 1, In : Endocrine journal. 66, 10, p. 853-857 5 p.

Research output: Contribution to journalArticle

Open Access
Growth Hormone-Secreting Pituitary Adenoma
Neurofibromatosis 1
Acromegaly
Neurofibromatosis 1 Genes
Follicular Adenocarcinoma
1 Citation (Scopus)

Actigraphy as an assessment of performance status in patients with advanced lung cancer

Fujisawa, D., Temel, J. S., Greer, J. A., El-Jawahri, A., Traeger, L., Jacobs, J. M., Cutrono, S. & Pirl, W. F., 2019 Jan 1, In : Palliative and Supportive Care.

Research output: Contribution to journalArticle

Actigraphy
Lung Neoplasms
Survival
Non-Small Cell Lung Carcinoma
Quality of Life
1 Citation (Scopus)

Actigraphy for evaluation of mood disorders: A systematic review and meta-analysis

Tazawa, Y., Wada, M., Mitsukura, Y., Takamiya, A., Kitazawa, M., Yoshimura, M., Mimura, M. & Kishimoto, T., 2019 Jun 15, In : Journal of Affective Disorders. 253, p. 257-269 13 p.

Research output: Contribution to journalReview article

Actigraphy
Mood Disorders
Meta-Analysis
Sleep
Therapeutics
Focal Adhesions
Neuroblastoma
Cell Movement
Shear stress
Adhesion

Activities of daily living among elderly persons with severe aortic stenosis

Fukui, S., Kawakami, M., Otaka, Y., Ishikawa, A., Yashima, F., Hayashida, K., Muraoka, K. & Liu, M., 2019 Jan 1, In : Disability and Rehabilitation.

Research output: Contribution to journalArticle

Aortic Valve Stenosis
Activities of Daily Living
Cerebrovascular Disorders
Heart Failure
Nutritional Status
1 Citation (Scopus)

Activity-Dependent Secretion of Synaptic Organizer Cbln1 from Lysosomes in Granule Cell Axons

Ibata, K., Kono, M., Narumi, S., Motohashi, J., Kakegawa, W., Kohda, K. & Yuzaki, M., 2019 Jun 19, In : Neuron. 102, 6, p. 1184-1198.e10

Research output: Contribution to journalArticle

Lysosomes
Cathepsin B
Axons
Synapses
Exocytosis

Actual practice of standard treatment for pulmonary nontuberculous mycobacteriosis in Japan

Morimoto, K., Izumi, K., Ato, M., Hasegawa, N. & Mitarai, S., 2019 Oct 1, In : Respiratory Medicine. 158, p. 67-69 3 p.

Research output: Contribution to journalArticle

Japan
Lung
Macrolides
Therapeutics
Lung Diseases
5 Citations (Scopus)

Acute and long-term effects of electroconvulsive therapy on human dentate gyrus

Takamiya, A., Plitman, E., Chung, J. K., Chakravarty, M., Graff-Guerrero, A., Mimura, M. & Kishimoto, T., 2019 Jan 1, (Accepted/In press) In : Neuropsychopharmacology.

Research output: Contribution to journalArticle

Electroconvulsive Therapy
Dentate Gyrus
splenotritin
Antidepressive Agents
Hippocampus
2 Citations (Scopus)

Acute Interstitial Nephritis With Karyomegalic Epithelial Cells After Nivolumab Treatment—Two Case Reports

Ryuzaki, M., Tokuyama, H., Uchiyama, K., Nakaya, H., Hasegawa, K., Miyashita, K., Konishi, K., Hashiguchi, A., Wakino, S. & Itoh, H., 2019 Jun 1, In : Clinical Medicine Insights: Case Reports. 12

Research output: Contribution to journalArticle

Open Access
Interstitial Nephritis
Epithelial Cells
Kidney
Therapeutics
Immunosuppressive Agents

Acute odontogenic infection combined with crowned dens syndrome: A case report

Soma, T., Asoda, S., Kimura, M., Munakata, K., Miyashita, H., Nakagawa, T. & Kawana, H., 2019 May 13, In : Journal of Medical Case Reports. 13, 1, 143.

Research output: Contribution to journalArticle

Open Access
Chondrocalcinosis
C-Reactive Protein
Cheek
Leukocyte Count
Odontoid Process

Acute Paraparesis Due to Protrusion of a Disc Following Lateral Interbody Fusion for Degenerative Kyphoscoliosis: A Case Report

Ruchirawan, S., Fujita, N., Yagi, M., Tsuji, O., Okada, E., Nagoshi, N., Ishii, K., Nakamura, M., Matsumoto, M. & Watanabe, K., 2019 Jan 1, In : JBJS case connector. 9, 1, p. e8

Research output: Contribution to journalArticle

Paraparesis
Spinal Canal
Decompression
Ilium
Spinal Stenosis

A Cyber-Physical Learning Environment Design for Study Trajectory Creation

Hayashi, Y., Nakamura, R., Hasegawa, O., Kitano, Y. & Kiyoki, Y., 2019 Sep, IES 2019 - International Electronics Symposium: The Role of Techno-Intelligence in Creating an Open Energy System Towards Energy Democracy, Proceedings. Zainudin, A. & Yunanto, A. A. (eds.). Institute of Electrical and Electronics Engineers Inc., p. 76-81 6 p. 8901640. (IES 2019 - International Electronics Symposium: The Role of Techno-Intelligence in Creating an Open Energy System Towards Energy Democracy, Proceedings).

Research output: Chapter in Book/Report/Conference proceedingConference contribution

Learning Environment
Education
Trajectories
Trajectory
E-learning

A Cycle-to-Cycle Variation Extraction Method for Flow Field Analysis in SI IC Engines Based on Turbulence Scales

Matsuda, M., Yokomori, T., Minamoto, Y., Shimura, M., Tanahashi, M. & Iida, N., 2019 Jan 15, In : SAE Technical Papers. 2019-January, January

Research output: Contribution to journalConference article

Electric sparks
Ignition
Flow fields
Turbulence
Engines
1 Citation (Scopus)

Adaptation to HIF1a deletion in hypoxic cancer cells by upregulation of GLUT14 and creatine metabolism

Valli, A., Morotti, M., Zois, C. E., Albers, P. K., Soga, T., Feldinger, K., Fischer, R., Frejno, M., McIntyre, A., Bridges, E., Haider, S., Buffa, F. M., Baban, D., Rodriguez, M., Yanes, O., Whittington, H. J., Lake, H. A., Zervou, S., Lygate, C. A., Kessler, B. M. & 1 others, Harris, A. L., 2019 Jul 1, In : Molecular Cancer Research. 17, 7, p. 1531-1544 14 p.

Research output: Contribution to journalArticle

Open Access
Creatine
Up-Regulation
Glycolysis
Neoplasms
Phosphofructokinases

Addition of canagliflozin to insulin improves glycaemic control and reduces insulin dose in patients with type 2 diabetes mellitus: A randomized controlled trial

Torimoto, K., Okada, Y., Goshima, Y., Tokutsu, A., Sato, Y. & Tanaka, Y., 2019 Jan 1, In : Diabetes, Obesity and Metabolism.

Research output: Contribution to journalArticle

Type 2 Diabetes Mellitus
Randomized Controlled Trials
Insulin
Blood Glucose
Hypoglycemia

A deadline-aware scheduling scheme for connected car services using mobile networks with quality fluctuation

Itoh, N., Morita, M., Iwai, T., Satoda, K. & Kubo, R., 2019 Mar 1, In : IEICE Transactions on Communications. E102B, 3, p. 474-483 10 p.

Research output: Contribution to journalArticle

Open Access
Wireless networks
Railroad cars
Scheduling
Long Term Evolution (LTE)
Health

A Decentralized Force Controller Synthesis for Compliant Robots Driven by Series Elastic Actuators

Sariyildiz, E., Mutlu, R., Nozaki, T. & Murakami, T., 2019 May 24, Proceedings - 2019 IEEE International Conference on Mechatronics, ICM 2019. Institute of Electrical and Electronics Engineers Inc., p. 661-666 6 p. 8722923. (Proceedings - 2019 IEEE International Conference on Mechatronics, ICM 2019).

Research output: Chapter in Book/Report/Conference proceedingConference contribution

Decentralized
Force control
Actuator
Actuators
Force Control
70 Citations (Scopus)

A defined commensal consortium elicits CD8 T cells and anti-cancer immunity

Tanoue, T., Morita, S., Plichta, D. R., Skelly, A. N., Suda, W., Sugiura, Y., Narushima, S., Vlamakis, H., Motoo, I., Sugita, K., Shiota, A., Takeshita, K., Yasuma-Mitobe, K., Riethmacher, D., Kaisho, T., Norman, J. M., Mucida, D., Suematsu, M., Yaguchi, T., Bucci, V. & 8 others, Inoue, T., Kawakami, Y., Olle, B., Roberts, B., Hattori, M., Xavier, R. J., Atarashi, K. & Honda, K., 2019 Jan 31, In : Nature. 565, 7741, p. 600-605 6 p.

Research output: Contribution to journalArticle

Immunity
T-Lymphocytes
Listeriosis
Histocompatibility
Microbiota

Adenovirus type 5 community-Acquired pneumonia in an immunocompetent patient

Masaki, K., Asakura, T., Sakurai, K. & Ohkusu, K., 2019 Apr 1, In : BMJ case reports. 12, 4, e228914.

Research output: Contribution to journalComment/debate

Open Access
Pulmonary Medicine
Bronchitis
Adenoviridae
Communicable Diseases
Pneumonia

Adherence to the guidelines and the pathological diagnosis of high-risk gastrointestinal stromal tumors in the real world

The members of the STAR ReGISTry Study Group, 2019 Jan 1, In : Gastric Cancer.

Research output: Contribution to journalArticle

Open Access
Guideline Adherence
Gastrointestinal Stromal Tumors
Pathology
Neoplasms
Registries
3 Citations (Scopus)

Adipokines and aging: Findings from centenarians and the very old

Arai, Y., Kamide, K. & Hirose, N., 2019 Jan 1, In : Frontiers in Endocrinology. 10, MAR, 142.

Research output: Contribution to journalReview article

Open Access
Adipokines
Insulin Resistance
Adiponectin
Homeostasis
Obesity

A Diprotonated Porphyrin as an Electron Mediator in Photoinduced Electron Transfer in Hydrogen-Bonded Supramolecular Assemblies

Suzuki, W., Kotani, H., Ishizuka, T., Kawano, M., Sakai, H., Hasobe, T., Ohkubo, K., Fukuzumi, S. & Kojima, T., 2019 May 9, In : Journal of Physical Chemistry C. 123, 18, p. 11529-11538 10 p.

Research output: Contribution to journalArticle

Porphyrins
porphyrins
assemblies
Hydrogen
electron transfer

Adrenergic receptor antagonism induces neuroprotection and facilitates recovery from acute ischemic stroke

Monai, H., Wang, X., Yahagi, K., Lou, N., Mestre, H., Xu, Q., Abe, Y., Yasui, M., Iwai, Y., Nedergaard, M. & Hirase, H., 2019 May 28, In : Proceedings of the National Academy of Sciences of the United States of America. 166, 22, p. 11010-11019 10 p.

Research output: Contribution to journalArticle

Adrenergic Receptors
Stroke
Aquaporin 4
Aquaporins
Adrenergic Antagonists
4 Citations (Scopus)

Adsorption-Desorption Control of Fibronectin in Real Time at the Liquid/Polymer Interface on a Quartz Crystal Microbalance by Thermoresponsivity

Li, J., Kaku, T., Tokura, Y., Matsukawa, K., Homma, K., Nishimoto, T., Hiruta, Y., Akimoto, A. M., Nagase, K., Kanazawa, H. & Shiratori, S., 2019 Jan 1, In : Biomacromolecules.

Research output: Contribution to journalArticle

Quartz crystal microbalances
Fibronectins
Desorption
Polymers
Adsorption
1 Citation (Scopus)

Adsorption state of NO on Ir(111) surfaces under excess O 2 coexisting condition

Ikeda, H., Koike, Y., Shiratori, K., Ueda, K., Shirahata, N., Isegawa, K., Toyoshima, R., Masuda, S., Mase, K., Nito, T. & Kondoh, H., 2019 Jul 1, In : Surface Science. 685, p. 1-6 6 p.

Research output: Contribution to journalArticle

Iridium
iridium
Adsorption
adsorption
crystal surfaces

Advanced deceleration control considering driving resistance by predicting the position of pedestrians

Nakamura, Y. & Murakami, T., 2019 Jan 1, In : IEEJ Journal of Industry Applications. 8, 2, p. 334-341 8 p.

Research output: Contribution to journalArticle

Open Access
Model predictive control
Deceleration
Controllers
Experiments

Advances in hematopoietic stem cell transplantation in the Asia-Pacific region: the second report from APBMT 2005–2015

Registry Committee of the Asia-Pacific Blood and Marrow Transplantation Group (APBMT), 2019 Jan 1, In : Bone Marrow Transplantation.

Research output: Contribution to journalArticle

Hematopoietic Stem Cell Transplantation
China
Hemoglobinopathies
Vietnam
Pakistan
1 Citation (Scopus)
Indigo Carmine
Ulcerative Colitis
Pulmonary Hypertension
Intussusception
Liver Diseases

A Familial Case of a Whole Germline CDC73 Deletion Discordant for Primary Hyperparathyroidism

Hatabu, N., Katori, N., Sato, T., Maeda, N., Suzuki, E., Komiyama, O., Tsutsui, H., Nagao, T., Nakauchi-Takahashi, H., Matsunaga, T., Ishii, T., Hasegawa, T. & Yamazawa, K., 2019 Jan 1, In : Hormone Research in Paediatrics.

Research output: Contribution to journalArticle

Primary Hyperparathyroidism
Genes
Hypophosphatemia
Parathyroid Neoplasms
Parathyroidectomy

Affective and temporal orientation of thoughts: Electrophysiological evidence

Ito, Y., Shibata, M., Tanaka, Y., Terasawa, Y. & Umeda, S., 2019 Sep 15, In : Brain Research. 1719, p. 148-156 9 p.

Research output: Contribution to journalArticle

Evoked Potentials
Anxiety
Depression
Cues
Personality

AffectiveHMD: Facial expression recognition in head mounted display using embedded photo reflective sensors

Murakami, M., Kikui, K., Suzuki, K., Nakamura, F., Fukuoka, M., Masai, K., Sugiura, Y. & Sugimoto, M., 2019 Jul 28, ACM SIGGRAPH 2019 Emerging Technologies, SIGGRAPH 2019. Association for Computing Machinery, Inc, (ACM SIGGRAPH 2019 Emerging Technologies, SIGGRAPH 2019).

Research output: Chapter in Book/Report/Conference proceedingConference contribution

Display devices
Virtual reality
Sensors
Synchronization
Helmet mounted displays

A fine-grained multicasting of configuration data for coarse-grained reconfigurable architectures

Kojima, T. & Amano, H., 2019 Jan 1, In : IEICE Transactions on Information and Systems. E102D, 7, p. 1247-1256 10 p.

Research output: Contribution to journalArticle

Open Access
Reconfigurable architectures
Multicasting
Processing
Program processors
Energy utilization
Open Access
Germ-Line Mutation
Brain Neoplasms
Lung Neoplasms
Prostatic Neoplasms
Neoplasm Metastasis

A Fixed-Point Analysis of Regularized Dual Averaging under Static Scenarios

Yukawa, M. & Yamada, I., 2019 Mar 4, 2018 Asia-Pacific Signal and Information Processing Association Annual Summit and Conference, APSIPA ASC 2018 - Proceedings. Institute of Electrical and Electronics Engineers Inc., p. 207-211 5 p. 8659576. (2018 Asia-Pacific Signal and Information Processing Association Annual Summit and Conference, APSIPA ASC 2018 - Proceedings).

Research output: Chapter in Book/Report/Conference proceedingConference contribution

Personal digital assistants
1 Citation (Scopus)

aflak: Visual programming environment enabling end-to-end provenance management for the analysis of astronomical datasets

Boussejra, M. O., Uchiki, R., Takeshima, Y., Matsubayashi, K., Takekawa, S., Uemura, M. & Fujishiro, I., 2019 Mar 1, In : Visual Informatics. 3, 1, p. 1-8 8 p.

Research output: Contribution to journalArticle

Open Access
Astronomy
Interchanges
Interoperability
Visualization

A Flexible Tactile Sensor to Detect Stiffness Distribution Without Measuring Displacement

Nagatom, T. & Miki, N., 2019 Jun 1, 2019 20th International Conference on Solid-State Sensors, Actuators and Microsystems and Eurosensors XXXIII, TRANSDUCERS 2019 and EUROSENSORS XXXIII. Institute of Electrical and Electronics Engineers Inc., p. 551-553 3 p. 8808756. (2019 20th International Conference on Solid-State Sensors, Actuators and Microsystems and Eurosensors XXXIII, TRANSDUCERS 2019 and EUROSENSORS XXXIII).

Research output: Chapter in Book/Report/Conference proceedingConference contribution

Tactile Sensor
stiffness
Stiffness
Sensors
Tissue

A fusion control of impedance and vibration suppression for a manipulator with flexible base

Mori, R. & Murakami, T., 2019 Feb 1, Proceedings - 2019 IEEE International Conference on Industrial Technology, ICIT 2019. Institute of Electrical and Electronics Engineers Inc., p. 42-47 6 p. 8754973. (Proceedings of the IEEE International Conference on Industrial Technology; vol. 2019-February).

Research output: Chapter in Book/Report/Conference proceedingConference contribution

Manipulators
Fusion reactions
Robots
Error analysis
Accidents

Agaricus brasiliensis KA21 May Prevent Diet-Induced Nash through Its Antioxidant, Anti-Inflammatory, and Anti-Fibrotic Activities in the Liver

Nakamura, A., Zhu, Q., Yokoyama, Y., Kitamura, N., Uchida, S., Kumadaki, K., Tsubota, K. & Watanabe, M., 2019 Jan 1, In : Foods. 8, 11, 546.

Research output: Contribution to journalArticle

Open Access
Agaricus subrufescens
Agaricus
Fatty Liver
alcoholism
Anti-Inflammatory Agents

Age-associated theophylline metabolic activity corresponds to the ratio of 1,3-dimethyluric acid to theophylline in mice

Kuroda, Y., Taguchi, K., Enoki, Y., Matsumoto, K., Hori, S. & Kizu, J., 2019 Jan 1, In : Biological and Pharmaceutical Bulletin. 42, 8, p. 1423-1427 5 p.

Research output: Contribution to journalArticle

Open Access
Theophylline
Acids
Serum
1,3-dimethyluric acid
Aptitude

Age group differences in association between IADL decline and depressive symptoms in community-dwelling elderly

Kiyoshige, E., Kabayama, M., Gondo, Y., Masui, Y., Inagaki, H., Ogawa, M., Nakagawa, T., Yasumoto, S., Akasaka, H., Sugimoto, K., Ikebe, K., Arai, Y., Ishizaki, T., Rakugi, H. & Kamide, K., 2019 Nov 13, In : BMC Geriatrics. 19, 1, 309.

Research output: Contribution to journalArticle

Open Access
Independent Living
Activities of Daily Living
Age Groups
Depression
Odds Ratio

A genetic study of a newly found population of siberian salamander, salamandrella keyserlingii (amphibia, caudata)

Matsui, M., Yoshikawa, N., Tanaka-Ueno, T., Sato, T., Takenaka, S., Terui, S., Oppata, Y. & Tominaga, A., 2019 Jan 1, In : Current Herpetology. 38, 2, p. 122-127 6 p.

Research output: Contribution to journalArticle

Caudata
Amphibia
salamanders and newts
Japan
cytochrome b

Age-Related Conjunctival P2Y2 Receptor Alterations in the Cu, Zn-Superoxide Dismutase-1 (Sod1)-Knockout Dry Eye Model Mice

Dogru, M., Shinzawa, M., Kojima, T., Shimizu, T. & Tsubota, K., 2019 Nov 1, In : Eye & contact lens. 45, 6, p. 405-409 5 p.

Research output: Contribution to journalArticle

Purinergic P2Y2 Receptors
Tears
Staining and Labeling
Fluorescein
Messenger RNA

Age-Related Trends in Home Blood Pressure, Home Pulse Rate, and Day-to-Day Blood Pressure and Pulse Rate Variability Based on Longitudinal Cohort Data: The Ohasama Study

Satoh, M., Metoki, H., Asayama, K., Murakami, T., Inoue, R., Tsubota-Utsugi, M., Matsuda, A., Hirose, T., Hara, A., Obara, T., Kikuya, M., Nomura, K., Hozawa, A., Imai, Y. & Ohkubo, T., 2019 Aug 6, In : Journal of the American Heart Association. 8, 15, e012121.

Research output: Contribution to journalArticle

Open Access
Heart Rate
Blood Pressure
Sex Characteristics
Linear Models
Japan
1 Citation (Scopus)

A high BNP level predicts an improvement in exercise tolerance after a successful catheter ablation of persistent atrial fibrillation

Katsumata, Y., Tamura, Y., Kimura, T., Kosaka, S., Sadahiro, T., Nishiyama, T., Aizawa, Y., Azuma, K., Fukuda, K. & Takatsuki, S., 2019 Jan 1, (Accepted/In press) In : Journal of Cardiovascular Electrophysiology.

Research output: Contribution to journalArticle

Exercise Tolerance
Catheter Ablation
Atrial Fibrillation
Heart Failure
Brain Natriuretic Peptide

A high-resolution time-based resistance-to-digital converter with TDC and counter

Nakagawa, S., Horikoshi, K. & Ishikuro, H., 2019 Jan 22, 2018 IEEE 61st International Midwest Symposium on Circuits and Systems, MWSCAS 2018. Institute of Electrical and Electronics Engineers Inc., p. 242-245 4 p. 8623991. (Midwest Symposium on Circuits and Systems; vol. 2018-August).

Research output: Chapter in Book/Report/Conference proceedingConference contribution

Electric power utilization
Bandwidth
Sensors
5 Citations (Scopus)

A high-throughput neurohistological pipeline for brain-wide mesoscale connectivity mapping of the common marmoset

Lin, M. K., Takahashi, Y. S., Huo, B. X., Hanada, M., Nagashima, J., Hata, J., Tolpygo, A. S., Ram, K., Lee, B. C., Miller, M. I., Rosa, M. G., Sasaki, E., Iriki, A., Okano, H. & Mitra, P., 2019 Feb 5, In : eLife. 8

Research output: Contribution to journalArticle

Open Access
Callithrix
Brain
Pipelines
Throughput
Atlases
1 Citation (Scopus)

A Human Induced Pluripotent Stem Cell-Derived Tissue Model of a Cerebral Tract Connecting Two Cortical Regions

Kirihara, T., Luo, Z., Chow, S. Y. A., Misawa, R., Kawada, J., Shibata, S., Khoyratee, F., Vollette, C. A., Volz, V., Levi, T., Fujii, T. & Ikeuchi, Y., 2019 Apr 26, In : iScience. 14, p. 301-311 11 p.

Research output: Contribution to journalArticle

Open Access
Induced Pluripotent Stem Cells
Axons
Neurons
Brain
Stem Cells
6 Citations (Scopus)

A Human iPSC Double-Reporter System Enables Purification of Cardiac Lineage Subpopulations with Distinct Function and Drug Response Profiles

Zhang, J. Z., Termglinchan, V., Shao, N. Y., Itzhaki, I., Liu, C., Ma, N., Tian, L., Wang, V. Y., Chang, A. C. Y., Guo, H., Kitani, T., Wu, H., Lam, C. K., Kodo, K., Sayed, N., Blau, H. M. & Wu, J. C., 2019 May 2, In : Cell stem cell. 24, 5, p. 802-811.e5

Research output: Contribution to journalArticle

Pharmaceutical Preparations
In Vitro Techniques

A hypothesis of state covariance decorrelation effects to partial observability SLAM

Ahmad, H., Othman, N. A., Saari, M. M., Ramli, M. S., Mazlan, M. B. M. & Namerikawa, T., 2019 May 1, In : Indonesian Journal of Electrical Engineering and Computer Science. 14, 2, p. 588-596 9 p.

Research output: Contribution to journalArticle

Simultaneous Localization and Mapping
Observability
Matrix Norm
Partial
Matrix Inversion