Search results for "Topic"
showing 10 items of 2844 documents
An overview of the clinical efficacy of mirtazapine
2002
Mirtazapine is at least as effective as the tricyclic antidepressants and trazodone in a wide range of patient subgroups including in- and out-patients with moderate to severe depression. It also appears to be at least as effective as the serotonin and noradrenaline reuptake inhibitor venlafaxine in the treatment of severely depressed melancholic patients. When compared with the selective serotonin reuptake inhibitors (SSRIs), mirtazapine shows a significantly earlier onset of action. Further analysis of a study comparing mirtazapine with the SSRI paroxetine indicated that early improvement was a highly sensitive predictor of later stable response for both drugs. The positive predictive val…
Preface to Special Issue of ChemSusChem on Perovskite Optoelectronics
2017
This Editorial introduces one of two companion Special Issues on "Halide Perovskites for Optoelectronics Applications" in ChemSusChem and Energy Technology following the ICMAT 2017 Conference in Singapore. More information on the other Special Issue can be found in the Editorial published in Energy Technology.
La qualità dell’aria indoor: una priorità ambientale e sanitaria
2009
Multi-label Classification Using Stacked Hierarchical Dirichlet Processes with Reduced Sampling Complexity
2018
Nonparametric topic models based on hierarchical Dirichlet processes (HDPs) allow for the number of topics to be automatically discovered from the data. The computational complexity of standard Gibbs sampling techniques for model training is linear in the number of topics. Recently, it was reduced to be linear in the number of topics per word using a technique called alias sampling combined with Metropolis Hastings (MH) sampling. We propose a different proposal distribution for the MH step based on the observation that distributions on the upper hierarchy level change slower than the document-specific distributions at the lower level. This reduces the sampling complexity, making it linear i…
Comparison of MeSH terms and KeyWords Plus terms for more accurate classification in medical research fields. A case study in cannabis research
2021
Abstract KeyWords Plus and Medical Subject Headings (MeSH) are widely used in bibliometric studies for topic mapping. The objective of this study is to compare the two description systems in documents about cannabis research to find the concordance between systems and establish whether there is neutrality in topic mapping. A total of 25,593 articles from 1970 to 2019 were drawn from Web of Science's Core Collection and Medline and analyzed. The tidytext library, Zipf's law, topic modeling tools, the contingency coefficient, Cramer's V, and Cohen's kappa were used. The results included 10,107 MeSH terms and 28,870 KeyWords Plus terms. The Zipf distribution of the terms was different for each…
Online Sparse Collapsed Hybrid Variational-Gibbs Algorithm for Hierarchical Dirichlet Process Topic Models
2017
Topic models for text analysis are most commonly trained using either Gibbs sampling or variational Bayes. Recently, hybrid variational-Gibbs algorithms have been found to combine the best of both worlds. Variational algorithms are fast to converge and more efficient for inference on new documents. Gibbs sampling enables sparse updates since each token is only associated with one topic instead of a distribution over all topics. Additionally, Gibbs sampling is unbiased. Although Gibbs sampling takes longer to converge, it is guaranteed to arrive at the true posterior after infinitely many iterations. By combining the two methods it is possible to reduce the bias of variational methods while …
A Survey of Multi-Label Topic Models
2019
Every day, an enormous amount of text data is produced. Sources of text data include news, social media, emails, text messages, medical reports, scientific publications and fiction. To keep track of this data, there are categories, key words, tags or labels that are assigned to each text. Automatically predicting such labels is the task of multi-label text classification. Often however, we are interested in more than just the pure classification: rather, we would like to understand which parts of a text belong to the label, which words are important for the label or which labels occur together. Because of this, topic models may be used for multi-label classification as an interpretable mode…
Using Topic Modeling Methods for Short-Text Data: A Comparative Analysis
2020
With the growth of online social network platforms and applications, large amounts of textual user-generated content are created daily in the form of comments, reviews, and short-text messages. As a result, users often find it challenging to discover useful information or more on the topic being discussed from such content. Machine learning and natural language processing algorithms are used to analyze the massive amount of textual social media data available online, including topic modeling techniques that have gained popularity in recent years. This paper investigates the topic modeling subject and its common application areas, methods, and tools. Also, we examine and compare five frequen…
Airway topical anaesthesia for awake fibreoptic intubation - a reply
2016
Update on the Management of Pediatric Psoriasis: An Italian Consensus
2022
Introduction Psoriasis affects children with a considerable burden in early life. Treating pediatric psoriasis is challenging also because of the lack of updated specific guidelines. With the recent approval of several biologics for pediatric psoriasis and the ongoing COVID-19 pandemic, the management of young psoriatic patients is facing major changes. A revision of treatment recommendations is therefore needed. Methods In September 2021, a board of six Italian dermatologists convened to update treatment recommendations. The board issued evidence- and consensus-based statements covering relevant areas of pediatric psoriasis, namely: assessment of psoriasis severity, management of children …