Masao Niwa

421 total citations
22 papers, 315 citations indexed

About

Masao Niwa is a scholar working on Cardiology and Cardiovascular Medicine, Surgery and Polymers and Plastics. According to data from OpenAlex, Masao Niwa has authored 22 papers receiving a total of 315 indexed citations (citations by other indexed papers that have themselves been cited), including 10 papers in Cardiology and Cardiovascular Medicine, 7 papers in Surgery and 5 papers in Polymers and Plastics. Recurrent topics in Masao Niwa's work include Membrane Separation and Gas Transport (5 papers), Synthesis and properties of polymers (5 papers) and Cardiac Valve Diseases and Treatments (4 papers). Masao Niwa is often cited by papers focused on Membrane Separation and Gas Transport (5 papers), Synthesis and properties of polymers (5 papers) and Cardiac Valve Diseases and Treatments (4 papers). Masao Niwa collaborates with scholars based in Japan. Masao Niwa's co-authors include Hiroyoshi Kawakami, Shoji Nagaoka, Shin-nosuke Goto, Hisato Takagi, Yusuke Mizuno, Takuya Umemoto, Toshiyuki Kanamori, Akira Kaito, Hirotaka Yamamoto and Eiichi Okazaki and has published in prestigious journals such as Macromolecules, Journal of Membrane Science and Applied Catalysis A General.

In The Last Decade

Masao Niwa

17 papers receiving 307 citations

Peers — A (Enhanced Table)

Peers by citation overlap · career bar shows stage (early→late) cites · hero ref

Name h Career Trend Papers Cites
Masao Niwa Japan 12 127 102 93 73 57 22 315
Mehmet Kış Türkiye 11 38 0.3× 64 0.6× 38 0.4× 53 0.7× 97 1.7× 42 408
Pei‐Ru Li Taiwan 11 22 0.2× 123 1.2× 65 0.7× 70 1.0× 37 0.6× 29 425
Nisa Patel United Kingdom 7 165 1.3× 45 0.4× 45 0.5× 72 1.0× 28 0.5× 10 306
Lizhi Tang China 13 93 0.7× 53 0.5× 7 0.1× 50 0.7× 47 0.8× 34 540
Magda Sayed Egypt 10 25 0.2× 31 0.3× 20 0.2× 151 2.1× 13 0.2× 19 347
Tomohiro Maeda Japan 15 38 0.3× 45 0.4× 33 0.4× 30 0.4× 330 5.8× 34 612
Daniel Kim United States 13 21 0.2× 129 1.3× 12 0.1× 14 0.2× 112 2.0× 36 508
Yong-Joon Lee South Korea 11 26 0.2× 117 1.1× 37 0.4× 39 0.5× 22 0.4× 21 297
Xiaojuan Du China 5 85 0.7× 29 0.3× 7 0.1× 38 0.5× 27 0.5× 18 366

Countries citing papers authored by Masao Niwa

Since Specialization
Citations

This map shows the geographic impact of Masao Niwa's research. It shows the number of citations coming from papers published by authors working in each country. You can also color the map by specialization and compare the number of citations received by Masao Niwa with the expected number of citations based on a country's size and research output (numbers larger than one mean the country cites Masao Niwa more than expected).

Fields of papers citing papers by Masao Niwa

Since Specialization
Physical SciencesHealth SciencesLife SciencesSocial Sciences

This network shows the impact of papers produced by Masao Niwa. Nodes represent research fields, and links connect fields that are likely to share authors. Colored nodes show fields that tend to cite the papers produced by Masao Niwa. The network helps show where Masao Niwa may publish in the future.

Co-authorship network of co-authors of Masao Niwa

This figure shows the co-authorship network connecting the top 25 collaborators of Masao Niwa. A scholar is included among the top collaborators of Masao Niwa based on the total number of citations received by their joint publications. Widths of edges represent the number of papers authors have co-authored together. Node borders signify the number of papers an author published with Masao Niwa. Masao Niwa is excluded from the visualization to improve readability, since they are connected to all nodes in the network.

All Works

20 of 20 papers shown
1.
Niwa, Masao, et al.. (2018). A Case of Adult Intestinal Malrotation Diagnosed Preoperatively with Computed Tomography and Treated with a Laparoscopic Ladd Procedure. Nihon Rinsho Geka Gakkai Zasshi (Journal of Japan Surgical Association). 79(6). 1226–1230.
2.
Niwa, Masao, et al.. (2017). Controlled silylation of MoVTeNb mixed oxide catalyst for the selective oxidation of propane to acrylic acid. Applied Catalysis A General. 549. 152–160. 17 indexed citations
3.
Niwa, Masao, et al.. (2016). [Four cases of ceftriaxone-associated biliary pseudolithiasis].. PubMed. 113(2). 281–8. 2 indexed citations
4.
Takahashi, Kei, et al.. (2015). A Case of Granulocyte-colony Stimulating Factor-producing Rectal Cancer. Nihon Rinsho Geka Gakkai Zasshi (Journal of Japan Surgical Association). 76(11). 2769–2773.
5.
Hayashi, Masatoshi, et al.. (2015). A Case of Ruptured Malignant Lymphoma of the Spleen. Nihon Rinsho Geka Gakkai Zasshi (Journal of Japan Surgical Association). 76(2). 387–391.
6.
Hayashi, Masatoshi, et al.. (2015). A Case of Non-invasive Ductal Carcinoma of the Male Breast that was Detected by Screening FDG-PET. Nihon Rinsho Geka Gakkai Zasshi (Journal of Japan Surgical Association). 76(12). 2909–2913.
7.
Takagi, Hisato, Masao Niwa, Yusuke Mizuno, et al.. (2013). A meta-analysis comparing observed 30-day all-cause mortality with the Society of Thoracic Surgeons Predicted Risk of Mortality in contemporary studies using Valve Academic Research Consortium definitions. International Journal of Cardiology. 168(2). 1598–1602. 4 indexed citations
8.
Takagi, Hisato, et al.. (2013). A meta-analysis of randomized trials of telmisartan vs. valsartan therapy for blood pressure reduction. Hypertension Research. 36(7). 627–633. 7 indexed citations
9.
Takagi, Hisato, Masao Niwa, Yusuke Mizuno, Shin-nosuke Goto, & Takuya Umemoto. (2013). Telmisartan as a metabolic sartan: The first meta-analysis of randomized controlled trials in metabolic syndrome. Journal of the American Society of Hypertension. 7(3). 229–235. 27 indexed citations
10.
Takagi, Hisato, Yusuke Mizuno, Masao Niwa, & Shin-nosuke Goto. (2013). A meta-analysis of randomized trials for repeat revascularization following off-pump versus on-pump coronary artery bypass grafting. Interactive Cardiovascular and Thoracic Surgery. 17(5). 878–880. 16 indexed citations
11.
Takagi, Hisato, Masao Niwa, Yusuke Mizuno, Shin-nosuke Goto, & Takuya Umemoto. (2013). A Meta-Analysis of Transcatheter Aortic Valve Implantation Versus Surgical Aortic Valve Replacement. The Annals of Thoracic Surgery. 96(2). 513–519. 18 indexed citations
12.
Takagi, Hisato, et al.. (2013). A meta-analysis of randomized controlled trials of azilsartan therapy for blood pressure reduction. Hypertension Research. 37(5). 432–437. 23 indexed citations
13.
Takagi, Hisato, Masao Niwa, Yusuke Mizuno, et al.. (2013). Effects of rosuvastatin versus atorvastatin on small dense low-density lipoprotein: a meta-analysis of randomized trials. Heart and Vessels. 29(3). 287–299. 11 indexed citations
14.
Takagi, Hisato, Masao Niwa, Yusuke Mizuno, Shin-nosuke Goto, & Takuya Umemoto. (2013). Incidence, predictors, and prognosis of acute kidney injury after transcatheter aortic valve implantation: A summary of contemporary studies using Valve Academic Research Consortium definitions. International Journal of Cardiology. 168(2). 1631–1635. 7 indexed citations
15.
Takagi, Hisato, Masao Niwa, Yusuke Mizuno, Shin-nosuke Goto, & Takuya Umemoto. (2012). The Last Judgment upon abdominal aortic aneurysm screening. International Journal of Cardiology. 167(5). 2331–2332. 14 indexed citations
16.
Niwa, Masao, Shoji Nagaoka, & Hiroyoshi Kawakami. (2006). Preparation of novel fluorinated block copolyimide membranes for gas separation. Journal of Applied Polymer Science. 100(3). 2436–2442. 23 indexed citations
17.
Niwa, Masao. (2004). Surface orientation effect of asymmetric polyimide hollow fibers on their gas transport properties. Journal of Membrane Science. 230(1-2). 141–148. 16 indexed citations
18.
Niwa, Masao, Hiroyoshi Kawakami, Masayoshi KANNO, et al.. (2001). Gas transfer and blood compatibility of asymmetric polyimide hollow fiber. Journal of Biomaterials Science Polymer Edition. 12(5). 533–542. 15 indexed citations
19.
Niwa, Masao, et al.. (2001). Gas Separation of Asymmetric 6FDA Polyimide Membrane with Oriented Surface Skin Layer. Macromolecules. 34(26). 9039–9044. 52 indexed citations
20.
Niwa, Masao, et al.. (2000). Fabrication of an asymmetric polyimide hollow fiber with a defect-free surface skin layer. Journal of Membrane Science. 171(2). 253–261. 54 indexed citations

Rankless uses publication and citation data sourced from OpenAlex, an open and comprehensive bibliographic database. While OpenAlex provides broad and valuable coverage of the global research landscape, it—like all bibliographic datasets—has inherent limitations. These include incomplete records, variations in author disambiguation, differences in journal indexing, and delays in data updates. As a result, some metrics and network relationships displayed in Rankless may not fully capture the entirety of a scholar's output or impact.

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