Recent observations have found a large number of supermassive black holes already in place in the first few hundred million years after the Big Bang, many of which seem to be overmassive relative to their host galaxy stellar mass when compared with local relation. Several different models have been proposed to explain these findings, ranging from heavy seeds to light seeds experiencing bursts of high accretion rate. Yet, current datasets are unable to differentiate between these various scenarios.
View Article and Find Full Text PDFThe cytogenetic and molecular heterogeneity of acute myeloid leukemia (AML) is characterized as a contributing factor in the disparity of treatment outcomes and clinical outcomes seen among ethnic and racial groups. In this study, we have retrospectively evaluated the karyotypes of 800 adult Hispanic AML patients from Puerto Rico (PR). Acute promyelocytic leukemia with is the most common recurrent cytogenetic abnormality, compatible with previously published results.
View Article and Find Full Text PDFEnergetically favorable local interactions can overcome the entropic cost of chain ordering and cause otherwise flexible polymers to adopt regularly repeating backbone conformations. A prominent example is the α helix present in many protein structures, which is stabilized by , + 4 hydrogen bonds between backbone peptide units. With the increased chemical diversity offered by unnatural amino acids and backbones, it has been possible to identify regularly repeating structures not present in proteins, but to date, there has been no systematic approach for identifying new polymers likely to have such structures despite their considerable potential for molecular engineering.
View Article and Find Full Text PDFThe first observations of the James Webb Space Telescope (JWST) have revolutionized our understanding of the Universe by identifying galaxies at redshift z ≈ 13 (refs. ). In addition, the discovery of many luminous galaxies at Cosmic Dawn (z > 10) has suggested that galaxies developed rapidly, in apparent tension with many standard models.
View Article and Find Full Text PDFThis review focuses on the most frequent whole-body MRI applications in patients with rheumatological pathologies, for which this tool can be helpful to both radiologists and clinicians. It reports technical aspects of the acquisition of both 1.5 and 3.
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