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External ballistics of Pleistocene hand-thrown spears: experimental performance data and implications for human evolution
The appearance of weaponry - technology designed to kill - is a critical but poorly established threshold
in human evolution. It is an important behavioural marker representing evolutionary changes in
ecology, cognition, language and social behaviours. While the earliest weapons are often considered
to be hand-held and consequently short-ranged, the subsequent appearance of distance weapons is a
crucial development. Projectiles are seen as an improvement over contact weapons, and are considered
by some to have originated only with our own species in the Middle Stone Age and Upper Palaeolithic.
Despite the importance of distance weapons in the emergence of full behavioral modernity, systematic
experimentation using trained throwers to evaluate the ballistics of thrown spears during fight and at
impact is lacking. This paper addresses this by presenting results from a trial of trained javelin athletes,
providing new estimates for key performance parameters. Overlaps in distances and impact energies
between hand-thrown spears and spearthrowers are evidenced, and skill emerges as a signifcant factor in
successful use. The results show that distance hunting was likely within the repertoire of hunting strategies
of Neanderthals, and the resulting behavioural flexibility closely mirrors that of our own specie
Quantitative Microscopy Reveals Centromeric Chromatin Stability, Size, and Cell Cycle Mechanisms to Maintain Centromere Homeostasis
The deposited item is a book chapter and is part of the series "Centromeres and Kinetochores" published by the publisher Springer Verlag. The deposited book chapter is a post-print version and has been submitted to peer reviewing. There is no public supplementary material available for this publication. This publication hasn't any creative commons license associated.Centromeres are chromatin domains specified by nucleosomes containing the histone H3 variant, CENP-A. This unique centromeric structure is at the heart of a strong self-templating epigenetic mechanism that renders centromeres heritable. We review how specific quantitative microscopy approaches have contributed to the determination of the copy number, architecture, size, and dynamics of centromeric chromatin and its associated centromere complex and kinetochore. These efforts revealed that the key to long-term centromere maintenance is the slow turnover of CENP-A nucleosomes, a critical size of the chromatin domain and its cell cycle-coupled replication. These features come together to maintain homeostasis of a chromatin locus that directs its own epigenetic inheritance and facilitates the assembly of the mitotic kinetochore.There are no funders and sponsors indicated explicitly in the document.info:eu-repo/semantics/publishedVersio
Effects of Anacetrapib in Patients with Atherosclerotic Vascular Disease
BACKGROUND:
Patients with atherosclerotic vascular disease remain at high risk for cardiovascular events despite effective statin-based treatment of low-density lipoprotein (LDL) cholesterol levels. The inhibition of cholesteryl ester transfer protein (CETP) by anacetrapib reduces LDL cholesterol levels and increases high-density lipoprotein (HDL) cholesterol levels. However, trials of other CETP inhibitors have shown neutral or adverse effects on cardiovascular outcomes.
METHODS:
We conducted a randomized, double-blind, placebo-controlled trial involving 30,449 adults with atherosclerotic vascular disease who were receiving intensive atorvastatin therapy and who had a mean LDL cholesterol level of 61 mg per deciliter (1.58 mmol per liter), a mean non-HDL cholesterol level of 92 mg per deciliter (2.38 mmol per liter), and a mean HDL cholesterol level of 40 mg per deciliter (1.03 mmol per liter). The patients were assigned to receive either 100 mg of anacetrapib once daily (15,225 patients) or matching placebo (15,224 patients). The primary outcome was the first major coronary event, a composite of coronary death, myocardial infarction, or coronary revascularization.
RESULTS:
During the median follow-up period of 4.1 years, the primary outcome occurred in significantly fewer patients in the anacetrapib group than in the placebo group (1640 of 15,225 patients [10.8%] vs. 1803 of 15,224 patients [11.8%]; rate ratio, 0.91; 95% confidence interval, 0.85 to 0.97; P=0.004). The relative difference in risk was similar across multiple prespecified subgroups. At the trial midpoint, the mean level of HDL cholesterol was higher by 43 mg per deciliter (1.12 mmol per liter) in the anacetrapib group than in the placebo group (a relative difference of 104%), and the mean level of non-HDL cholesterol was lower by 17 mg per deciliter (0.44 mmol per liter), a relative difference of -18%. There were no significant between-group differences in the risk of death, cancer, or other serious adverse events.
CONCLUSIONS:
Among patients with atherosclerotic vascular disease who were receiving intensive statin therapy, the use of anacetrapib resulted in a lower incidence of major coronary events than the use of placebo. (Funded by Merck and others; Current Controlled Trials number, ISRCTN48678192 ; ClinicalTrials.gov number, NCT01252953 ; and EudraCT number, 2010-023467-18 .)
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