Air was sampled from the porous firn layer at the NEEM site in Northern Greenland. We use an ensemble of ten reference tracers of known atmospheric history to characterise the transport properties of the site. By analysing uncertainties in both data and the reference gas atmospheric histories, we can objectively...
Full Text:
-4277, 2012
C. Buizert1, P. Martinerie2, V. V. Petrenko3, J. P. Severinghaus4, C. M. Trudinger5, E
Air was sampled from the porous firn layer at the NEEM site in Northern Greenland. We use an ensemble of ten reference tracers of known atmospheric history to characterise the transport properties of the site. By analysing uncertainties in both data and the reference gas atmospheric histories, we can objectively...
Full Text:
for NEEM, Northern Greenland
C. Buizert1, P. Martinerie2, V. V. Petrenko3,*, J. P. Severinghaus4, C
Air was sampled from the porous firn layer at the NEEM site in Northern Greenland. We use an ensemble of ten reference tracers of known atmospheric history to characterise the transport properties of the site. By analysing uncertainties in both data and the reference gas atmospheric histories, we can objectively...
Radiocarbon measurements at ice margin sites and blue ice areas can potentially be used for ice dating, ablation rate estimates and paleoclimatic reconstructions. Part of the measured signal comes from in situ cosmogenic ¹⁴C production in ice, and this component must be well understood before useful information can be extracted...
Horizontal ice-core sites, where ancient ice is exposed at the glacier surface, offer unique opportunities for paleo-studies of trace components requiring large sample volumes. Following previous work at the Pâkitsoq ice margin in West Greenland, we use a combination of geochemical parameters measured in the ice matrix (δ¹⁸O[subscript ice]) and...
We present the first successful ⁸¹Kr-Kr radiometric dating of ancient polar ice. Krypton was extracted from the air bubbles in four ~350 kg polar ice samples from Taylor Glacier in the McMurdo Dry Valleys, Antarctica, and dated using Atom Trap Trace Analysis (ATTA). The ⁸¹Kr radiometric ages agree with independent...
We present a new method developed for measuring radiocarbon of methane (¹⁴CH₄) in ancient air samples
extracted from glacial ice and dating 11,000–15,000 calendar years before present. The small size (~20 μg CH₄ carbon), low
CH₄ concentrations ([CH₄], 400–800 parts per billion [ppb]), high carbon monoxide concentrations ([CO]), and low...
We present techniques for obtaining large (∼100 L STP) samples of ancient air for analysis of ¹⁴C of methane (¹⁴CH₄) and other trace constituents. Paleoatmospheric ¹⁴CH₄ measurements should constrain the fossil fraction of past methane budgets, as well as provide a definitive test of methane clathrate involvement in large and...
Viruses were defined as one of the two principal types of organisms
in the biosphere, namely, as capsid-encoding organisms in
contrast to ribosome-encoding organisms, i.e., all cellular life
forms. Structurally similar, apparently homologous capsids are
present in a huge variety of icosahedral viruses that infect bacteria,
archaea, and eukaryotes. These...
Important progress in understanding replication, interactions with host plants, and evolution of closteroviruses enabled engineering of several vectors for gene expression and virus-induced gene silencing. Due to the broad host range of closteroviruses, these vectors expanded vector applicability to include important woody plants such as citrus and grapevine. Furthermore, large...
Viruses and/or virus-like selfish elements are associated with all cellular life forms and are the most abundant biological entities on Earth, with the number of virus particles in many environments exceeding the number of cells by one to two orders of magnitude. The genetic diversity of viruses is commensurately enormous...
The Northern Rubber Boa (Charina bottae) is a small, secretive boa native to the Pacific Northwest. Despite this being possibly the highest latitude boas and one of only two boas native to the continental U.S., it has received surprisingly little attention. Most of the research on the natural history of...
A common issue with extracorporeal medical devices is blood clotting due to bio-incompatibility. Systemic anticoagulants are often prescribed to mitigate the coagulation issues. However, such drugs can lead to further complications, for example hemorrhaging. One solution to improve the hemocompatibility of blood-contacting medical devices are biomaterials, such as slippery liquid...
The World Trade Center disaster brought into focus, tragically, the need for well-designed evacuation systems in modem buildings. Today, designing an efficient evacuation system has become an integral part of designing large buildings. Simulation software enables an evacuation system to be evaluated. Modern day buildings, whether airports, auditoriums, public office...
Objective: There are currently 6,000-7,000 recognized rare disorders, affecting approximately 1 in 10 Americans. While each rare disease is unique, the experience of having a rare condition is relatively common. It is this common experience of having a rare disease during the Covid-19 pandemic that we aim to represent with...
Taking long-term electrical measurements of a large number of neurons simultaneously is required for many modern neuroscience experiments. However, such experiments are currently limited by the shortcomings of traditional neurosensing technology. For example, there is a significant mechanical mismatch between rigid silicon probes and soft biological tissues. This mismatch can...
The overall goal of this study was to utilize apple pomace, the byproduct from juice processing, as a renewable source of fiber to create sustainable packaging using molded pulp technology. The goal was accomplished through two studies: 1) to modify apple pomace fibers for increasing relative cellulose composition and improving...
Bangladesh is a developing country with burdens of environmental pollution and disparities in maternal and child health. Arsenic, manganese, and lead are pervasive environmental contaminants throughout Bangladesh with major exposures through drinking water and ambient pollution. Chronic exposures to arsenic, manganese, and lead in sensitive populations such as pregnant women,...
Marin County, located in the northern San Francisco Bay Area in California, faces significant threats due to climate change, including more frequent wildfires, flooding, and increased temperatures. Adaptation and mitigation efforts are necessary in order to promote resilience amidst these changing conditions. Scorecards and similar evaluation tools have previously been...
Chainsaws serve as one of the primary tools used by logging corporations, ranches, and farms for forestry management. Lubricating oil remains one of the heaviest operational expenditures for chainsaws. This largely in part due to chainsaw lubrication being a total loss system in which nearly all lubricating oil applied is...
Utilization of zebrafish, Danio rerio, has steadily increased and its applications have expanded into numerous fields of science. Applying elevated temperatures (32°C to 37°C) to this organism has allowed researchers to conduct climate change, human cancer and infectious disease studies. Though zebrafish can be acclimated from the standard 28°C to...
Low carbon steels (LCS) due to their high strength-to-cost ratio are one of the most ubiquitous materials used for a wide range of applications, including but not limited to automotive, construction, and transportation. However, the low corrosion resistance of LCS in neutral, acidic, or saline environments limits its utilization and...
The azalea lace bug (Stephanitis pyrioides Scott) is a global pest of rhododendrons and azaleas (Rhododendron spp.). It is originally from Asia, has been established in the eastern U.S. for the past century, and was recently detected in the Pacific Northwest in 2008-2009. Stephanitis pyrioides feeds on the underside of...
Forests are some of the most ecologically diverse and dense habitats on the planet. Research shows that the endophyte community, or the fungi, bacteria, and viruses within a forest ecosystem is highly diverse. Fungal endophytes are defined as fungi that live within the tissues of host plants. Relationships between fungal...
Single nucleotide polymorphisms (SNPs) can be used as markers to infer population genetic structure. For Mycoplasma cynos, a pathogen associated with infectious respiratory disease among canines and other animals, SNPs may help to elucidate ecological and evolutionary relationships among the strains that reside in the upper respiratory tract of canines...
Genetic counseling, a healthcare profession centered on communicating genetic information to patients and helping them understand it, has been rapidly evolving with the development of genetic sequencing and editing technology over the past decades. Consequently, future and current genetic counselors must address societal and ethical implications, as well as historical...
Tree-like patterns are ubiquitous in nature. Botanical trees, river networks, and blood systems are the most well-known examples of complex hierarchical systems met in observations. Interestingly, many of such systems exhibit statistical self-similarity. There are two main types of self-similarity: Horton self-similarity and Tokunaga self-similarity. Although there is an increased...
Planarity has been successfully exploited to design faster and more accurate approximation algorithms for many graph optimization problems. The celebrated theorem of Kuratowski completely characterizes planar graphs as those excluding K_5 and K_{3,3} as minors. Kuratowski's theorem allows one to generalize planar graphs to H-minor-free graphs: those that exclude a...
The gut microbiome influences human disease including Type 2 diabetes, obesity and metabolic syndrome and interacts with the innate immune system. The human cathelicidin antimicrobial peptide (hCAMP), an important component of the innate immune system, and vitamin D and xanthohumol, a natural compound found in beer hops, regulate its expression....
Computational simulations of disks are becoming an important tool to predict the the evolution of protostars and disks to better understand the formation of planets. Past research has shown that the evolution of disks and their protostar can be altered through the interaction between gravity and hydrodynamic instabilities. We perform...
This thesis project has the following specific objectives: (i) Determine pathogenicity of Globodera ellingtonae to potato utilizing two trials conducted over a 16 week period, (ii) Elucidate the host range of G. ellingtonae using a variety of different Solanum weed species and crop species, and (iii) Characterize population decline of...
This paper presents an evaluation of the cable loading
support capacity of red alder, Alnus rubra Bong., Sitka
spruce, Picea sitchensis (Bong.) Carr, and western hemlock,
Tsuga heterophylla (Raf.) Sarg., tail trees. Capacity is
measured in terms of combined stress resulting from
compression and bending, rather than the traditional methods...
This research examines how marketing strategies of produce managers affect consumer expenditures for fresh apples and pears. The objective of this study is to determine how display size, point-of-purchase material, product origin, product information and display placement impact consumer expenditures for fresh apples and pears. These variables were incorporated into...
The International Atomic Energy Agency (IAEA) is the leading organization for monitoring nuclear facilities worldwide, and the Agency’s methods are constantly developing and improving in an effort to more effectively safeguard nuclear material. As such, the IAEA addresses near and long term risks in order to advance the capabilities of...
Osteosarcoma (OSA) is the most common primary skeletal tumor in dogs accounting for 85% of bone tumors and nearly 6% of all canine neoplasms. They are highly aggressive tumors that carry a poor prognosis despite intensive treatment, highlighting the need for more effective diagnostic and therapeutic tools. Recent research in...