OBJECTIVES The objective was to describe rates of dating aggression and related high-risk behavior among teens presenting to the emergency department (ED) seeking gynecologic care, compared to those seeking care for other reasons. METHODS Female patients ages 14-18 years presenting to the ED during the afternoon/evening shift of a large urban teaching hospital over a 19-month period were appr...

Radiometric dating--the process of determining the age of rocks from the decay of their radioactive elements-has been in widespread use for over half a century. There are over forty such techniques, each using a different radioactive element or a different way of measuring them. It has become increasingly clear that these radiometric dating techniques agree with each other and as a whole, prese...

The development of flexible electronics operating at radio-frequencies (RF) requires materials that combine excellent electronic performance and the ability to withstand high levels of strain. In this work, we fabricate graphene field-effect transistors (GFETs) on flexible substrates from graphene grown by chemical vapor deposition (CVD). Our devices demonstrate unity-current-gain frequencies, ...

Among radio amateurs digital meteor burst communication has been discussed for many years. Despite this, no experiments on amateur basis have (to the knowledge of the author) been performed in Sweden or elsewhere in the world. During the past two years several amateurs have reported the random appearance of AX.25 packets from very distant stations. The propagation of these packets can only be e...

How to tell time: • Relative Time: putting events in time order. • Law of Superposition • Correlation of rock layers using fossils. William Smith " There is a wonderful order and regularity with which nature has disposed of fossils and assigned to each its peculiar stratum. " How to tell time: • Absolute Time: Determining age in years.

We observed an anomaly in the human electroencephalogram (EEG) associated with exposure to terrestrial trunked radio (TETRA) Radiofrequency Fields (RF). Here, we characterize the time and frequency components of the anomaly and demonstrate that it is an artefact caused by TETRA RF interfering with the EEG recording equipment and not by any direct or indirect effect on the brain.

Studies on the evolutionary history of ascomycetes in terms of time scale will help to understand historical patterns that shape their biodiversity. Until now most of dating studies of ascomycetes have focused on major events in fungal evolution but not on divergence events within smaller groups of fungi e.g. within Sordariomycetes. We used molecular dating to estimate the time of separation of...

This work focuses on the determination of time zero nuclear events considering Xe-135/I-135 isotopic activity ratio. Considered as relevant isotopes for CTBT, theses two radionuclides are usable radioactive release timing. According considered databases, some parameters namely A, U and F evaluated taking into account numerical difference between values from database. We found that these give di...

[1] A new groundwater dating procedure using the transient atmospheric signal of the environmental tracers SF5CF3, CFC-13, SF6, and CFC-12 was developed. The analytical procedure determines concentrations of the four tracers in air and water samples. SF5CF3 and CFC-13 can be used to date groundwaters in some environments where the CFCs and SF6 have previously failed because these new tracers ha...

This article traces the metrological history of radiocarbon, from the initial breakthrough devised by Libby, to minor (evolutionary) and major (revolutionary) advances that have brought (14)C measurement from a crude, bulk [8 g carbon] dating tool, to a refined probe for dating tiny amounts of precious artifacts, and for "molecular dating" at the 10 µg to 100 µg level. The metrological advances...