1,721,250 research outputs found
Phenomenological and residence time distribution models for unit operations in a continuous pharmaceutical manufacturing process
No full textInterest in continuous pharmaceutical manufacturing (CPM) technology is rapidly growing, with all major pharmaceutical companies developing products in their pipelines using this technology. As it has been extensively reported, CPM can deliver enormous advantages including faster product development, less material use, reduced capital cost due to small equipment size, superior process control, optimized performance, and more reliable quality manufacturing. Nevertheless, given the novel and complex nature of the technology, CPM systems require further study compared to traditional batch processes. CPM studies must be carefully designed, optimized, validated, and controlled as holistic system in order to operate robustly, efficiently, and provide the aforementioned advantages. To achieve CPM’s advantages in full, it is necessary to develop and implement a framework wherein the processes can be evaluated and studied as integrated systems. In this work, tools established in the process systems engineering (PSE) methodology were implemented to develop models that can aid CPM process design, evaluation, control, and optimization. The focus of this work included the development and implementation of computationally efficient phenomenological and residence time distribution models for systems in a CPM system. In the first two chapters of this work, a thorough review of the current implementation of models in the pharmaceutical industry is presented. Within the review, the different types of models currently implemented in the industry are enumerated followed by the challenges of their implementation. Among some of the most difficult challenges for modeling CPM powder-based systems is the ability to determine relationships between critical process inputs and outputs, and the ability capture the impact of material properties on the process. To overcome these challenges a framework for developing predictive phenomenological (i.e., engineering) models that include the effect of material properties on the process was developed. The third and fourth chapters of this work are devoted to describing the model development framework and provide an example case study of the methodology when it was successfully applied to a tablet compaction process. The successful integration of material property effects into the modeling of the pharmaceutical unit operation led to the development of a material property library that collected a wide array of property measurements for a number of pharmaceutically relevant materials. The material property library, described in the fifth chapter of this work, was used as a tool to determine the impact of material properties on: (1) residence time distribution experiments and (2) the operation of continuous powder feeding units. Residence time distribution (RTD) methods and models were studied in this work, as their application to characterize CPM systems has become standard. The effect of material properties on RTD methods were evaluated in the sixth chapter to provide recommendations for using the RTD methodology to characterize CPM units. Ultimately, the unit operation characterization and modeling framework presented in this work along with the recommendations offered for RTD experimentation and modeling were applied to the development of a dynamic phenomenological and RTD model for a continuous powder feeding unit. The model, described in the seventh chapter of this work, was used to predict the behavior of the CPM-specific unit over a wide range of material property and process inputs.Ph.D.Includes bibliographical referencesby Manuel Escotet Espinoz
Going Beyond Counting First Authors in Author Co-citation Analysis
Full text linkThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
Variations on the Author
Full text link“Variations on the Author” discusses two of Eduardo Coutinho’s recent films (Um Dia na Vida, from 2010, and Últimas Conversas, posthumously released in 2015) and their contribution to the general question of documentary authorship. The director’s filmography is characterized by a consistent yet self-effacing form of authorial self-inscription: Coutinho often features as an interviewer that rather than express opinions propels discourses; an interviewer that is good at listening. This mode of self-inscription characterizes him as an author who is not expressive but who is nonetheless markedly present on the screen. In Um Dia na Vida, however, Coutinho is completely absent form the image, while Últimas Conversas, on the contrary, includes a confessional prologue that moves the director from the margins to the center of his films. This article examines the ways in which these works stand out in the filmography of a director who offers new insights into the notion of cinematic authorship
Appropriate Similarity Measures for Author Cocitation Analysis
Full text linkWe provide a number of new insights into the methodological discussion about author cocitation analysis. We first argue that the use of the Pearson correlation for measuring the similarity between authors’ cocitation profiles is not very satisfactory. We then discuss what kind of similarity measures may be used as an alternative to the Pearson correlation. We consider three similarity measures in particular. One is the well-known cosine. The other two similarity measures have not been used before in the bibliometric literature. Finally, we show by means of an example that our findings have a high practical relevance.information science;Pearson correlation;cosine;similarity measure;author cocitation analysis
Dispelling the Myths Behind First-author Citation Counts
Full text linkWe conducted a full-scale evaluative citation analysis study of scholars in the XML research field to explore just how different from each other author rankings resulting from different citation counting methods actually are, and to demonstrate the capability of emerging data and tools on the Web in supporting more realistic citation counting methods. Our results contest some common arguments for the continued
use of first-author citation counts in the evaluation of scholars, such as high correlations between author rankings by first-author citation counts and other citation
counting methods, and high costs of using more realistic citation counting methods that are not well-supported by the ISI databases. It is argued that increasingly available digital full text research papers make it possible for citation analysis studies to go beyond what the ISI databases have directly supported and to employ more
sophisticated methods
koamabayili/VECTRON-author-checklist: VECTRON author checklist
No full textWe have done our best to complete the author checklist relating to the use of animals in the hut study. Note that the objective for the hut study was to evaluate the IRS treatment applications for residual efficacy against Anopheles mosquitoes, including the local An. coluzzii mosquito population. Cows were only used to attract mosquitoes into the huts and no tests were carried out directly on the cows. The author checklist is intended for use with studies where experiments are carried out on animals, which is why we have had such difficulty in completing this for the hut study, as many of the questions do not relate to how the cows were used
Author-wise bibliometric analysis based on entropy.
No full textAuthor-wise bibliometric analysis based on entropy.</p
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