Shikimate pathway in apicomplexan parasites

No abstract available

Characteristics of signals originating near the lithium-diffused N+ contact of high purity germanium p-type point contact detectors

A study of signals originating near the lithium-diffused n+ contact of p-type point contact (PPC) high purity germanium detectors (HPGe) is presented. The transition region between the active germanium and the fully dead layer of the n+ contact is examined. Energy depositions in this transition region are shown to result in partial charge collection. This provides a mechanism for events with a well defined energy to contribute to the continuum of the energy spectrum at lower energies. A novel technique to quantify the contribution from this source of background is introduced. Experiments that operate germanium detectors with a very low energy threshold may benefit from the methods presented herein

The Majorana Demonstrator: Progress towards showing the feasibility of a tonne-scale 76Ge neutrinoless double-beta decay experiment

The Majorana Demonstrator will search for the neutrinoless double-beta decay (0vββ) of the 76Ge isotope with a mixed array of enriched and natural germanium detectors. The observation of this rare decay would indicate the neutrino is its own anti-particle, demonstrate that lepton number is not conserved, and provide information on the absolute mass-scale of the neutrino. The Demonstrator is being assembled at the 4850 foot level of the Sanford Underground Research Facility in Lead, South Dakota. The array will be contained in a low-background environment and surrounded by passive and active shielding. The goals for the Demonstrator are: demonstrating a background rate less than 3 t-1 y-1 in the 4 keV region of interest (ROI) surrounding the 2039 keV 76Ge endpoint energy; establishing the technology required to build a tonne-scale germanium based double-beta decay experiment; testing the recent claim of observation of 0vββ [1]; and performing a direct search for light WIMPs (3-10 GeV/c2)

The Majorana project

Building a 0νβ β experiment with the ability to probe neutrino mass in the inverted hierarchy region requires the combination of a large detector mass sensitive to 0νβ β, on the order of 1-tonne, and unprecedented background levels, on the order of or less than 1 count per year in the 0νβ β signal region. The Majorana Collaboration proposes a design based on using high-purity enriched 76Ge crystals deployed in ultra- low background electroformed Cu cryostats and using modern analysis techniques that should be capable of reaching the required sensitivity while also being scalable to a 1- tonne size. To demonstrate feasibility, the collaboration plans to construct a prototype system, the Majorana Demonstrator, consisting of 30 kg of 86% enriched 76Ge detectors and 30 kg of natural or isotope-76-depleted Ge detectors. We plan to deploy and evaluate two different Ge detector technologies, one based on a p-type configuration and the other on n-type

Temperature and symbiosis affect lesion recovery in experimentally wounded, facultatively symbiotic temperate corals

The health of most reef-building corals depends upon an intracellular symbiosis with photosynthetic dinoflagellates of the genus Symbiodinium that is acutely sensitive to increasing ocean temperatures. However, distinguishing the individual effects of both temperature and symbiotic state on coral health is difficult to investigate experimentally in most tropical corals because the symbiosis is obligate. Here, we varied temperature (9, 18, 24°C) and symbiotic state (symbiotic, aposymbiotic) in the facultatively symbiotic, temperate scleractinian coral Astrangia poculata to explore the individual impact of temperature and symbiosis on wound healing, an important component of coral resilience, by determining wound size using calibrated photographs and characterizing developmental stage through the healing process over time. Symbiotic corals demonstrated a significant healing advantage over corals with lower densities of S. psygmophilum (aposymbiotic state), regardless of temperature. In addition, overall recovery success of both symbiotic states increased with temperature. These data suggest that a functional symbiotic relationship with S. psygmophilum promotes lesion recovery despite heterotrophic energy sources. Reductions in healing rate and tissue cover near the wound site under cold temperatures suggest that wound healing is compromised during the winter in these temperate corals. This study demonstrates that supplemental energy sources from symbiosis, coupled with optimal growth conditions, promote wound healing and may offer insight into factors enhancing wound recovery in tropical corals.This work was funded by the PADI foundation, the Boston University Marine Program, and the New England Aquarium. We thank Kiki Ballotti, Georgie Burruss, Nicholas Lawrence, Samantha Pelletier, Aaron Pilnick, and Ryan Schosberg for assistance with photography and data collection. We are also grateful to Tasia Blough, Julio Camperio-Ciani, Gregory Coote, Lukas DeFilippo, Corbin Kuntz, Georgia Luddecke, Katrina Malakhoff, Jessie Matthews, and Matthew Tohl for their roles in the husbandry and maintenance of coral specimens. We appreciate the input of the anonymous reviewers that contributed to the improvement of this manuscript. (PADI foundation; Boston University Marine Program; New England Aquarium