54 research outputs found
Coastal high-frequency radars in the Mediterranean ??? Part 2: Applications in support of science priorities and societal needs
International audienceThe Mediterranean Sea is a prominent climate-change hot spot, with many socioeconomically vital coastal areas being the most vulnerable targets for maritime safety, diverse met-ocean hazards and marine pollution. Providing an unprecedented spatial and temporal resolution at wide coastal areas, high-frequency radars (HFRs) have been steadily gaining recognition as an effective land-based remote sensing technology for continuous monitoring of the surface circulation, increasingly waves and occasionally winds. HFR measurements have boosted the thorough scientific knowledge of coastal processes, also fostering a broad range of applications, which has promoted their integration in coastal ocean observing systems worldwide, with more than half of the European sites located in the Mediterranean coastal areas. In this work, we present a review of existing HFR data multidisciplinary science-based applications in the Mediterranean Sea, primarily focused on meeting end-user and science-driven requirements, addressing regional challenges in three main topics: (i) maritime safety, (ii) extreme hazards and (iii) environmental transport process. Additionally, the HFR observing and monitoring regional capabilities in the Mediterranean coastal areas required to underpin the underlying science and the further development of applications are also analyzed. The outcome of this assessment has allowed us to provide a set of recommendations for future improvement prospects to maximize the contribution to extending science-based HFR products into societally relevant downstream services to support blue growth in the Mediterranean coastal areas, helping to meet the UN's Decade of Ocean Science for Sustainable Development and the EU's Green Deal goals
Coastal high-frequency radars in the Mediterranean ??? Part 1: Status of operations and a framework for future development
Due to the semi-enclosed nature of the Mediterranean
Sea, natural disasters and anthropogenic activities impose
stronger pressures on its coastal ecosystems than in any
other sea of the world.With the aim of responding adequately
to science priorities and societal challenges, littoral waters
must be effectively monitored with high-frequency radar
(HFR) systems. This land-based remote sensing technology
can provide, in near-real time, fine-resolution maps of the
surface circulation over broad coastal areas, along with reliable
directional wave and wind information. The main goal
of this work is to showcase the current status of the Mediterranean
HFR network and the future roadmap for orchestrated
actions. Ongoing collaborative efforts and recent progress of
this regional alliance are not only described but also connected
with other European initiatives and global frameworks,
highlighting the advantages of this cost-effective instrument
for the multi-parameter monitoring of the sea state.
Coordinated endeavors between HFR operators from different
multi-disciplinary institutions are mandatory to reach a
mature stage at both national and regional levels, striving to
do the following: (i) harmonize deployment and maintenance
practices; (ii) standardize data, metadata, and quality control
procedures; (iii) centralize data management, visualization,
and access platforms; and (iv) develop practical applications
of societal benefit that can be used for strategic planning and
informed decision-making in the Mediterranean marine environment.
Such fit-for-purpose applications can serve for
search and rescue operations, safe vessel navigation, tracking
of marine pollutants, the monitoring of extreme events,
the investigation of transport processes, and the connectivity
between offshore waters and coastal ecosystems. Finally, future
prospects within the Mediterranean framework are discussed
along with a wealth of socioeconomic, technical, and
scientific challenges to be faced during the implementatio
Exceptional conservation of horse–human gene order on X chromosome revealed by high-resolution radiation hybrid mapping
Development of a dense map of the horse genome is key to efforts aimed at identifying genes controlling health, reproduction, and performance. We herein report a high-resolution gene map of the horse (Equus caballus) X chromosome (ECAX) generated by developing and typing 116 gene-specific and 12 short tandem repeat markers on the 5,000-rad horse × hamster whole-genome radiation hybrid panel and mapping 29 gene loci by fluorescence in situ hybridization. The human X chromosome sequence was used as a template to select genes at 1-Mb intervals to develop equine orthologs. Coupled with our previous data, the new map comprises a total of 175 markers (139 genes and 36 short tandem repeats, of which 53 are fluorescence in situ hybridization mapped) distributed on average at ≈880-kb intervals along the chromosome. This is the densest and most uniformly distributed chromosomal map presently available in any mammalian species other than humans and rodents. Comparison of the horse and human X chromosome maps shows remarkable conservation of gene order along the entire span of the chromosomes, including the location of the centromere. An overview of the status of the horse map in relation to mouse, livestock, and companion animal species is also provided. The map will be instrumental for analysis of X linked health and fertility traits in horses by facilitating identification of targeted chromosomal regions for isolation of polymorphic markers, building bacterial artificial chromosome contigs, or sequencing
Mechanism of and requirement for estrogen-regulated MYB expression in estrogen-receptor-positive breast cancer cells
MYB (the human ortholog of c-myb) is expressed in a high proportion of human breast tumors, and that expression correlates strongly with estrogen receptor (ER) positivity. This may reflect the fact that MYB is a target of estrogen/ER signaling. Because in many cases MYB expression appears to be regulated by transcriptional attenuation or pausing in the first intron, we first investigated whether this mechanism was involved in estrogen/ER modulation of MYB. We found that this was the case and that estrogen acted directly to relieve attenuation due to sequences within the first intron, specifically, a region potentially capable of forming a stem–loop structure in the transcript and an adjacent poly(dT) tract. Secondly, given the involvement of MYB in hematopoietic and colon tumors, we also asked whether MYB was required for the proliferation of breast cancer cells. We found that proliferation of ER+ but not ER− breast cancer cell lines was inhibited when MYB expression was suppressed by using either antisense oligonucleotides or RNA interference. Our results show that MYB is an effector of estrogen/ER signaling and provide demonstration of a functional role of MYB in breast cancer
A Method for Approximating Univariate Convex Functions using Only Function Value Evaluations
In this paper, piecewise linear upper and lower bounds for univariate convex functions are derived that are only based on function value information. These upper and lower bounds can be used to approximate univariate convex functions. Furthermore, new Sandwich algo- rithms are proposed, that iteratively add new input data points in a systematic way, until a desired accuracy of the approximation is obtained. We show that our new algorithms that use only function-value evaluations converge quadratically under certain conditions on the derivatives. Under other conditions, linear convergence can be shown. Some numeri- cal examples, including a Strategic investment model, that illustrate the usefulness of the algorithm, are given.
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