Assessments of the impact of construction, operation, and removal of large infrastructures and other human activities on the marine environment are limited because they do not fully quantify the background baseline conditions and relevant scales of natural variability. Baselines as defined in Environmental Impact Assessments typically reflect the status of the environment and its variability dr...

Radiative lifetimes from laser-induced fluorescence measurements, accurate to 5%, are reported for 41 oddparity levels of Hf ii. The lifetimes are combined with branching fractions measured using Fourier transform spectrometry to determine transition probabilities for 150 lines of Hf ii. Approximately half of these new transition probabilities overlap with recent independent measurements using ...

In STEM (Science, Technology, Engineering and Mathematics) education, mobile robot development and competition has become very popular. Mobile robot is an effective platform for stimulating student motivation at K-12 institutions as well as for rigorous engineering practices in colleges and universities. Objective estimation of mobile robot movements is critical in robot design and development ...

We study a new s-process path through an isomer of Re to improve a Re-Os nucleo-cosmochronometer. The nucleus Re is produced by this new path of Re(n,γ)Re(n,γ)Re. We measure a ratio of neutron capture cross-sections for the Re(n,γ)Re and Re(n,γ)Re reactions at thermal neutron energy because the ratio with the experimental uncertainty has not been reported. Using an activation method with reacto...

Introduction: One of the most debated subjects in meteoritics is the time scale of events that occurred during the early history of the solar system. Chronometers based on short lived nuclides, such as Al, Mn, Fe, Pd, I, Sm, were extensively studied during the last decades. Some of them were shown to afford chronological resolutions on the order of a few Ma to less than one Ma [e.g. 1,2]. This ...

OBJECTIVE This in vitro study evaluated the influence of luting agents on ultrasonic vibration time for intraradicular cast post removal. MATERIAL AND METHODS After endodontic treatment, 30 roots of extracted human canines were embedded in resin cylinders. The post-holes were prepared at 10 mm depth and their impressions were taken using autopolymerizing acrylic resin. After casting procedure...

An analysis of common units of measure for assessing program quality and programmer productivity reveals that some standard measures are intrinsically paradoxical. Lines of code per programmer month and cost per defect are in this category. Presented here are attempts to go beyond such paradoxical units as these. Also discussed is the usefulness of separating quality measurements into measures ...

Context. Stellar ages are extremely difficult to determine and often subject to large uncertainties, especially for field low-mass stars. We plan to carry out a calibration of the decrease in high-energy emissions of low-mass GKM stars with time, and therefore precise age determination is a key ingredient. The overall goal of our research is to study the time evolution of these high-energy emis...

Re-Os isotopic analyses of a single organic-rich sedimentary rock unit (ORS) of known depositional age, and at three levels of regional hydrocarbon maturity, show that hydrocarbon maturation does not affect the ability the Re-Os chronometer to yield a depositional age for such rocks. We present Re-Os isotope analyses from the Late Devonian Exshaw Formation in the subsurface of the Western Canad...

The aim of this in vitro study was to compare the time required for removal of intraradicular cast posts cemented with zinc phosphate (ZF) or glass ionomer cement (GIC), using two Brazilian ultrasound devices (BUD). Seventy two human inferior premolars with single root canals were sectioned transversally at the cementoenamel junction. In each specimen, the root canal was endodontically treated,...