Estimation of quantile regression models for survival data.

A system for querying, retrieving and analyzing
        protocol- and results-related information on clinical trials from
        four public registers, the 'European Union Clinical Trials Register'
        ('EUCTR', <https://www.clinicaltrialsregister.eu/>), 
        'ClinicalTrials.gov' (<https://clinicaltrials.gov/> and also 
        translating queries the retired classic interface), the 
        'ISRCTN' (<http://www.isrctn.com/>) and the
        'European Union Clinical Trials Information System'
        ('CTIS', <https://euclinicaltrials.eu/>). 
        Trial information is downloaded, converted and stored in a database 
        ('PostgreSQL', 'SQLite', 'DuckDB' or 'MongoDB'; via package 'nodbi'). 
        Documents in registers associated with trials can also be downloaded. 
        Other functions identify deduplicated records, 
        easily find and extract variables (fields) of interest even 
        from complex nested data as used by the registers, 
        merge variables and update queries. 
        The package can be used for meta-analysis and trend-analysis of
        the design and conduct as well as of the results of clinical trials.

Tools to create and query database from the U.S. National Library
  of Medicine's Clinical Trials database <https://clinicaltrials.gov/>. Functions
  provide access a variety of techniques for searching the data using range
  queries, categorical filtering, and by searching for full-text keywords. 
  Minimal graphical tools are also provided for interactively exploring the
  constructed data.

Computerized tomography (CT) can be used to assess certain wood properties when wood disks or logs are scanned. Wood density profiles (i.e. variations of wood density from pith to bark) can yield important information used for studies in forest resource assessment, wood quality and dendrochronology studies. The first step consists in transforming grey values from the scan images to density values. The packages then proposes a unique method to automatically locate the pith by combining an adapted Hough Transform method and a one-dimensional edge detector. Tree ring profiles (average ring density, earlywood and latewood density, ring width and percent latewood for each ring) are then obtained.