378 research outputs found
Design of pharmaceutical tablet formulation for a low water soluble drug : search for the critical concentration of starch based disintegrant applying percolation theory and F-CAD (Formulation-Computer Aided Design)
Get PDFThe topic of this PhD work is to search the critical concentration of starch based disintegrant applying percolation theory and F-CAD (Formulation-Computer Aided Design) in order to design a pharmaceutical tablet formulation for a low water soluble drug. Critical concentration of maize starch (MS) for a ternary mefenamic acid (MA) tablet formulation with respect to a minimum disintegration time is investigated. Additionally implemented application of F-CAD to compute the disintegration time of MA tablet formulation is presented. This topic is related to push forward the idea of Quality by Design (QbD) of FDA (Food and Drug Administration) / EMEA (European Medicines Agency) / PMDA (Pharmaceuticals and Medical Devices Agency) and the exploration of the design space according to ICH (International Conference of Harmonization) Q8.
The results of this work shows that the application of percolation theory is not limited to binary tablet formulation. The critical concentration of MS described by the renormalized MS concentration, MS/(MS+MA) applying the renormalization technique is always equal 0.198 (dimensionless). Moreover the critical concentration of MS is optimized using the spline approximation with the dataNESIA software. It is leading to a minimum disintegration time at 0.206, dimensionless, renormalized, which is very close to the experimental value of 0.198. According to the percolation theory, a minimum disintegration time corresponds to the formation of a continuous water-conducting cluster through the entire tablet. The critical volume fraction of an ‘infinite cluster’ that water can diffuse through the entire MA tablets are calculated with taking into account for the geometrical considerations between MS and MA particles based on random close packed (RCP) spheres system. The critical volume fraction of MS is calculated by the multiplication of critical concentration of MS and the solid fraction of MA tablets; which is within the range of 0.16 ± 0.01 (v/v). It is concluded that the critical volume fraction for three dimensional lattices is equal to 0.16 ± 0.01 (v/v); which is useful for the calculation of the critical concentration of starch based disintegrant in order to design the pharmaceutical tablet formulation based on scientific approach proposed by ICH Q8 guidance.
In addition, the disintegration behavior in the neighborhood of the percolation threshold is explained mathematically by the basic equation of the percolation theory, yielding a critical exponent q equal to 0.28 ± 0.06 (Quality of fit: r2 = 0.84). This value is close to the critical exponent for three dimensional lattices (q = 0.4). Thus, it is important, within a planned experimental design to optimize the disintegrant to take into account the percolation theory. However it has to be kept in mind that the determination of the percolation threshold and critical exponent does not give an answer about the absolute value of the disintegration time. Dissolution Simulation (DS) module, which is the one of F-CAD based on cellular automata algorithm is used to simulate the disintegration time of a MA tablet. Disintegration time of tablet is assumed as the time elapsed till the water is detected at the geometric center of the virtual tablet. Comparison of experimental disintegration time of MA tablet and computed specific time point for water to reach the geometric center of the tablet by using F-CAD software has been carried out and shown an acceptable correlation (Correlation coefficient: r = 0.81). The detailed evaluation of the data shows that there is still a need for optimization of F-CAD for the calculation of the disintegration time in order to achieve a similar or the same performance like in the prediction of the dissolution profile of a tablet formulation. It is concluded that F-CAD software is the only software so far, which is capable of computing the disintegration time of tablets. The software has a great potential to be improved and to be not only used for the safe prediction of the dissolution profile of a tablet formulation but also for a safe prediction of the disintegration time. Thus, such a software is one of the tools for the substitution of laboratory experiments for the purpose of the design and development of new pharmaceutical solid dosage forms. The replacement of expensive laboratory experiments by in-silico experiments is an important issue to reduce development costs and to comply with the requirements of ICH Q8 exploring the design space with response surface methodology. The results of this thesis show in addition that the application of percolation theory is a must in order to detect percolation thresholds. It is important to know the response surfaces close to the percolation threshold of sensitive tablet properties such as the disintegration time to get information about the robustness of the selected formulation. In this context one has to put the question forward if the application of percolation theory should be an integral part of the guidelines of ICH Q8 exploring the formulation design space
Letter from Shigeki Hiratsuka to [Dorothy] Nakamura, August 23, 1991
No full textCorrespondence from Shigeki Hiratsuka to Dorothy Nakamura regarding a copy of a letter from Jim Kolbe and the redress and reparations movement.The Japanese American Archival Collection documents the people, places, and daily life of Japanese Americans, primarily those who lived in the once thriving community of pre-war Florin in the Sacramento region, as well as the conditions in American incarceration camps during World War II. The approximately 7,000 original items include personal and official letters, photographs, diaries, arts and crafts, newsletters, textiles, camps artifacts, yearbooks and other publications
Letter from Dorothy Nakamura to Shigeki Hiratsuka, August 16, 1991
No full textCorrespondence from Dorothy Nakamura to Shigeki Hiratsuka regarding Hiratsuka's activism in gaining support for restitution payments to non-Japanese individuals who chose to live in an incarceration camp with their Japanese American partners.The Japanese American Archival Collection documents the people, places, and daily life of Japanese Americans, primarily those who lived in the once thriving community of pre-war Florin in the Sacramento region, as well as the conditions in American incarceration camps during World War II. The approximately 7,000 original items include personal and official letters, photographs, diaries, arts and crafts, newsletters, textiles, camps artifacts, yearbooks and other publications
Letter from Jim Kolbe, Member of Congress, to Shigeki Hiratsuka, August 15, 1991
No full textCorrespondence from Jim Kolbe to Shigeki Hiratsuka regarding Hiratsuka's inquiry about restitution for individuals incarcerated during World War II who were not of Japanese ancestry.The Japanese American Archival Collection documents the people, places, and daily life of Japanese Americans, primarily those who lived in the once thriving community of pre-war Florin in the Sacramento region, as well as the conditions in American incarceration camps during World War II. The approximately 7,000 original items include personal and official letters, photographs, diaries, arts and crafts, newsletters, textiles, camps artifacts, yearbooks and other publications
ヒト脳・眼窩内海綿状血管腫の病因への内皮間葉移行の関与
Get PDF京都大学0048新制・課程博士博士(医学)甲第21261号医博第4379号新制||医||1029(附属図書館)京都大学大学院医学研究科医学専攻(主査)教授 山下 潤, 教授 湊谷 謙司, 教授 羽賀 博典学位規則第4条第1項該当Doctor of Medical ScienceKyoto UniversityDFA
OPERATIVE EXPERIENCE OF RENAL ARTERY ANEURYSM IN A CONGENITAL SOLITALY KIDNEY
Get PDFRenal artery aneurysms in solitary kidney are rare. We experienced a case of congenital solitary kidney with non-calcified renal artery aneurysm. We treated the case by surgical method. The operation procedures were ligatures of the influx and exflux vessels of the aneurysm by transaneurysmal approach. Postoperative course was almost uneventful without transient increase of serum creatinine and blood urea nitrogen. Review of the literatures was made including consideration of the surgical methods for solitary kidney
The role of thoracic ultrasonography for evaluation of patients with decompensated chronic heart failure
No full textAbstractOBJECTIVESThis study examined the usefulness of thoracic ultrasonography for evaluation of fluid accumulation in patients with decompensated chronic heart failure (CHF) in comparison with physical signs, upright posteroanterior chest X-ray and echocardiography.BACKGROUNDDecompensated CHF is frequently accompanied by pleural effusion, suggesting that pleural effusion is a useful marker for confirming the diagnosis of the uncontrolled stage of CHF. Thoracic ultrasonography seems to be adequate for this purpose.METHODSPatients with uncontrolled CHF and an interpretable physical examination, chest X-ray, ultrasonogram for the heart and thorax and thoracic X-ray computed tomographic (CT) scan were enrolled in the study (n = 60). Patients free from thoracic and cardiovascular diseases served as a control (n = 22). Thoracic CT scan was used as the gold standard for the presence or absence of pleural effusion. Variables used to predict body fluid accumulation included the following: pulmonary rales, jugular venous distension or peripheral edema, roentgenographic evidence of pulmonary edema or pleural fluid, pericardial or pleural effusion on ultrasonographic study.RESULTSThe reported incidence of pleural effusion detected by thoracic ultrasonography was high (91%). The incidence of physical signs and roentgenographic signs of body fluid accumulation, however, was modest (56%) to low (33%). The best clinical variable for identifying patients with decompensated CHF was the detection of pleural fluid by thoracic ultrasonography (91% predictive accuracy). This variable also had high interobserver agreement (95% overall agreement, kappa = 0.70). There was only 41% to 65% predictive accuracy of other clinical variables, with 72% to 95% agreement (kappa = 0.400–0.848).CONCLUSIONSThoracic ultrasonography is a simple, sensitive and accurate method for the evaluation of body fluid accumulation in patients with decompensated CHF. This technique can be used to assist in making the diagnosis of decompensated CHF if other causes of pleural effusion have been clinically ruled out
[Photograph of Michi Weglyn receiving award]
No full textJapanese American Citizenship League (JACL) National President [Shigeki] Sugiyama presenting Michi Weglyn with the Japanese American of the Biennium Award.These materials are from box 73 and 74 of the Frank Chin Papers. The Frank Chin Papers contain personal and professional correspondence between Frank Chin and Michi Weglyn relating to particular projects on which either author was working as well as files related to the Day of Remembrance Tribute to Michi Weglyn
The program to implement the method using intermediate task for the text classification task
No full textThe program to implement the method using the intermediate task proposed in the paper below. This program can be applied to general text classification tasks and contains sample codes for 15 tasks like AG-news and SST2.
---
Kazuhiro Wada, Masaya Tsunokake, and Shigeki Matsubara. 2024. On an Intermediate Task for Classifying URL Citations on Scholarly Papers. In Proceedings of the 2024 Joint International Conference on Computational Linguistics, Language Resources and Evaluation (LREC-COLING 2024), pages 12359–12369, Torino, Italia. ELRA and ICCL.下記の論文の中間タスクを用いた手法を実装するためのプログラム．一般的なテキスト分類タスクに対応しており，15種類のタスク（e.g., AG-News, SST2）で使用するためのサンプルコードを含む．
---
Kazuhiro Wada, Masaya Tsunokake, and Shigeki Matsubara. 2024. On an Intermediate Task for Classifying URL Citations on Scholarly Papers. In Proceedings of the 2024 Joint International Conference on Computational Linguistics, Language Resources and Evaluation (LREC-COLING 2024), pages 12359–12369, Torino, Italia. ELRA and ICCL.Information on related papers:
@inproceedings{wada-etal-2024-intermediate,
title = "On an Intermediate Task for Classifying {URL} Citations on Scholarly Papers",
author = "Wada, Kazuhiro and
Tsunokake, Masaya and
Matsubara, Shigeki",
booktitle = "Proceedings of the 2024 Joint International Conference on Computational Linguistics, Language Resources and Evaluation (LREC-COLING 2024)",
month = may,
year = "2024",
address = "Torino, Italia",
publisher = "ELRA and ICCL",
url = "https://aclanthology.org/2024.lrec-main.1082/",
pages = "12359--12369"
}datase
- …
