753 research outputs found
A very brief description of LOFAR - the Low Frequency Array
LOFAR (Low Frequency Array) is an innovative radio telescope optimized for
the frequency range 30-240 MHz. The telescope is realized as a phased aperture
array without any moving parts. Digital beam forming allows the telescope to
point to any part of the sky within a second. Transient buffering makes
retrospective imaging of explosive short-term events possible. The scientific
focus of LOFAR will initially be on four key science projects (KSPs): 1)
detection of the formation of the very first stars and galaxies in the universe
during the so-called epoch of reionization by measuring the power spectrum of
the neutral hydrogen 21-cm line (Shaver et al. 1999) on the ~5' scale; 2)
low-frequency surveys of the sky with of order expected new sources; 3)
all-sky monitoring and detection of transient radio sources such as gamma-ray
bursts, x-ray binaries, and exo-planets (Farrell et al. 2004); and 4) radio
detection of ultra-high energy cosmic rays and neutrinos (Falcke & Gorham 2003)
allowing for the first time access to particles beyond 10^21 eV (Scholten et
al. 2006). Apart from the KSPs open access for smaller projects is also
planned. Here we give a brief description of the telescope.Comment: 2 pages, IAU GA 2006, Highlights of Astronomy, Volume 14, K.A. van
der Hucht, e
Barriers to accessing internationally controlled essential medicines in sub-saharan Africa: A scoping review
Background: Access to internationally controlled essential medicines (ICEMs), medicines that are listed on both the World Health Organization's Essential Medicines List and one of three international drug control conventions, remains problematic in Sub-Saharan Africa (SSA). Previous reviews have focused only on specific ICEMs or ICEM-related healthcare fields, but none have focused on all ICEMs as a distinct class. This scoping review therefore aims to identify the barriers to accessing ICEMs across all relevant healthcare fields in SSA. Methods: A scoping review was conducted across indexing platforms Embase, PubMed, Scopus and Web of Science of studies published between January 1 2012 and February 1 2022. Articles were eligible if they mentioned barriers to accessing ICEMs and/or ICEM-related healthcare fields, if studies were conducted in SSA, or included data on an SSA country within a multi-country study. The review was guided by the Access to Medicines from a Health System Perspective framework. Results: The search identified 5519 articles, of which 97 met the inclusion criteria. Many barriers to access were reported and were common across the ICEMs drug class. Main barriers were: at the individual level, the lack of knowledge about ICEMs; at the health service delivery level, low availability, stockouts, affordability, long distances to health facilities, insufficient infrastructure to store and distribute ICEMs, and lack of ICEM knowledge and training among healthcare workers; at the health sector level, lack of prioritisation of ICEM-related healthcare fields by governments and subsequent insufficient budget allocation. Cross-cutting, governance-related barriers pertained to lack of proper quantification systems, cumbersome procurement processes, and strict national laws controlling ICEMs, leading to overly restrictive prescription practices. Conclusion: This review showed that there are a multitude of barriers to accessing ICEMs in SSA across all health system levels. Many of the barriers identified are applicable to all ICEMs, highlighting the importance of tackling barriers for this entire class of drugs together
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