320 research outputs found
Nitrogen fixation by the cyanobacterium Nostoc punctiforme in response to variation in nitrogen availability, temperature, and atmospheric CO2 concentrations
The predominant input of available nitrogen (N) in boreal forest ecosystems originates from moss-associated cyanobacteria, which fix unavailable atmospheric N2, contribute to the soil N pool, and thereby support forest productivity. Although increases in N availability, temperature, and atmospheric CO2 concentrations are expected in Canada’s boreal region over the next century, little is known about the combined effects of these factors on N2 fixation by axenic cyanobacteria or the associated mechanisms. I assessed changes in N2 fixation by Nostoc punctiforme under different global environmental change scenarios and examined correlations between the response and changes in growth, heterocyst percentage, and heterocyst activity. With available N present, N. punctiforme did not perform N2 fixation or form heterocysts. Elevated CO2 stimulated growth and N2 fixation, but this result was influenced by a temperature-mediated growth cycle. Overall, my findings suggest a decrease in boreal N2 fixation rates in response to global environmental change
A 120nW 18.5kHz RC oscillator with comparator offset cancellation for ±0.25% temperature stability
Integrated low-frequency oscillators can replace crystal oscillators as sleep-mode timers to reduce the size and cost of wireless sensors [1]. Since the timer is one of the few continuously functioning circuits, minimizing its power consumption can greatly reduce sleep-mode power of highly duty-cycled systems. Temperature stability of the oscillator is important in order to minimize timing uncertainly and guard time for the radios, and thus maximizing sleep time. The voltage-averaging feedback method described in [2] achieves high stability in the MHz frequencies, but when scaled to the kHz range, requires very large filters. On the other extreme, gate leakage-based timers have been designed for sub-nW power consumption, but operate in the sub-Hz frequencies [3]. In the past, high accuracy RC oscillators in the kHz range have been designed with feed-forward correction [1] and self-chopped operation [4]. In this work, an offset cancellation architecture achieves long-term frequency stability and temperature stability while operating at lower power
The Vehicle, Fall 2007
Table of Contents
Is This Thing On?Nichole D\u27Antoniopage 1
Death Came KnockingJacob Dawsonpage 5
Awaiting DecemberRebecca Griffithpage 9
ginamarieElizabeth Hoodpage 11
She LongsJennifer O\u27Neilpage 12
ForgottenStephanie Drozdpage 13
Art House WomanGreg Harrellpage 14
Young Woman OlderAmanda Vealepage 15
FirstRebecca Griffithpage 17
FlowJacob Dawsonpage 19
Am Animal AwareDanielle Meyerpage 20
Geneva 04\u27Stephanie Guyerpage 21
Poland, 1942.Jennifer O\u27Neilpage 22
Witness to the Atrophy of ForestsDanielle Meyerpage 23
Helvellyn IJacob Fosterpage 24
Three Out of Five Ain\u27t BadThomas McElweepage 25
FarceAmanda Vealepage 31
Strength of EmotionJennifer O\u27Neilpage 32
About the Authors
Art Submissions
Prerequisite for a RequiemJenna Smithcover
Girl 3Jenna Smithpage 14
ManJenna Smithpage 16
Give Peace a ChanceMegan Mathypage 16
GraceJennifer O\u27Neilpage 20
Oh, the Places You\u27ll Go!Megan Mathypage 23https://thekeep.eiu.edu/vehicle/1086/thumbnail.jp
The Vehicle, Fall 2007
Table of Contents
Is This Thing On?Nichole D\u27Antoniopage 1
Death Came KnockingJacob Dawsonpage 5
Awaiting DecemberRebecca Griffithpage 9
ginamarieElizabeth Hoodpage 11
She LongsJennifer O\u27Neilpage 12
ForgottenStephanie Drozdpage 13
Art House WomanGreg Harrellpage 14
Young Woman OlderAmanda Vealepage 15
FirstRebecca Griffithpage 17
FlowJacob Dawsonpage 19
Am Animal AwareDanielle Meyerpage 20
Geneva 04\u27Stephanie Guyerpage 21
Poland, 1942.Jennifer O\u27Neilpage 22
Witness to the Atrophy of ForestsDanielle Meyerpage 23
Helvellyn IJacob Fosterpage 24
Three Out of Five Ain\u27t BadThomas McElweepage 25
FarceAmanda Vealepage 31
Strength of EmotionJennifer O\u27Neilpage 32
About the Authors
Art Submissions
Prerequisite for a RequiemJenna Smithcover
Girl 3Jenna Smithpage 14
ManJenna Smithpage 16
Give Peace a ChanceMegan Mathypage 16
GraceJennifer O\u27Neilpage 20
Oh, the Places You\u27ll Go!Megan Mathypage 23https://thekeep.eiu.edu/vehicle/1086/thumbnail.jp
Sheep Updates 2008 - part 3
This session covers fiveteen papers from different authors:
CONTROLLING FLY STRIKE
1. Breeding for Blowfly Resistance - Indicatoe Traits, LJE Karlsson, JC Greeff, L Slocombe, Department of Agriculture & Food, Western Australia
2.A practical method to select for breech strike resistance in non-pedigreed Merino flocks, LJE Karlsson, JC Greeff, L Slocombe, K. Jones, N. Underwood, Department of Agriculture & Food, Western Australia
3. Twice a year shearing - no mulesing, Fred Wilkinson, Producer, Brookton WA
BEEF
4. Commercial testing of a new tool for prediction of fatness in beef cattle, WD HoffmanA, WA McKiernanA, VH OddyB, MJ McPheeA, Cooperative Research Centre for Beef Genetic Technologies, A N.S.W. Deptartment of Primary Industries, B University of New England
5. A new tool for the prediction of fatness in beef cattle, W.A. McKiernanA, V.H. OddyB and M.J. McPheeC; Cooperative Research Centre for Beef Genetic Technologies, A N.S.W. Dept of Primary Industries, B University of New England, C N.S.W. Dept of Primary Industries Beef Industry Centre of Excellence.
6. Effect of gene markers for tenderness on eating quality of beef, B.L. McIntyre, CRC for Beef Genetic Technologies, Department of Agriculture and Food WA
7. Accelerating beef industry innovation through Beef Profit Partnerships, Parnell PF1,2, Clark RA1,3, Timms J1,3, Griffith G1,2, Alford A1,2, Mulholland C1 and Hyland P1,4,1Co-operative Research Centre for Beef Genetic Technologies; 2NSW Department of Primary Industries; 3 Qld Department of Primary Industries and Fisheries; 4The University of Queensland.
SUSTAINABILITY
8. The WA Sheep Industry - is it ethically and environmentally sustainable? Danielle England, Department of Agriculture and Food Western Australia
9. Overview of ruminant agriculture and greenhouse emissions, Fiona Jones, Department of Agriculture and Food Western Australia
10. Grazing for Nitrogen Efficiency, John Lucey, Martin Staines and Richard Morris, Department of Agriculture and Food Western Australia
11. Investigating potential adaptations to climate change for low rainfall farming system, Megan Abrahams, Caroline Peek, Dennis Van Gool, Daniel Gardiner, Kari-Lee Falconer, Department of Agriculture and Food Western Australia
SHEEP
12. Benchmarking ewe productivity through on-farm genetic comparisons, Sandra Prosser, Mario D’Antuono and Johan Greeff; Department of Agriculture and Food Western Australia
13. Increasing profitability by pregnancy scanning ewes, John Young1, Andrew Thompson2 and Chris Oldham2; 1Farming Systems Analysis Service, Kojonup, WA, 2Department of Agriculture and Food Western Australia
14. Targeted treatment of worm-affected sheep - more efficient, more sustainable, Brown Besier, Department of Agriculture and Food Western Australia
15. Improving Weaner Sheep Survival, Angus Campbell and Ralph Behrendt, Cooperative Research Centre for Sheep Industry Innovatio
Measurement of the cosmic ray spectrum above eV using inclined events detected with the Pierre Auger Observatory
A measurement of the cosmic-ray spectrum for energies exceeding
eV is presented, which is based on the analysis of showers
with zenith angles greater than detected with the Pierre Auger
Observatory between 1 January 2004 and 31 December 2013. The measured spectrum
confirms a flux suppression at the highest energies. Above
eV, the "ankle", the flux can be described by a power law with
index followed by
a smooth suppression region. For the energy () at which the
spectral flux has fallen to one-half of its extrapolated value in the absence
of suppression, we find
eV.Comment: Replaced with published version. Added journal reference and DO
Energy Estimation of Cosmic Rays with the Engineering Radio Array of the Pierre Auger Observatory
The Auger Engineering Radio Array (AERA) is part of the Pierre Auger
Observatory and is used to detect the radio emission of cosmic-ray air showers.
These observations are compared to the data of the surface detector stations of
the Observatory, which provide well-calibrated information on the cosmic-ray
energies and arrival directions. The response of the radio stations in the 30
to 80 MHz regime has been thoroughly calibrated to enable the reconstruction of
the incoming electric field. For the latter, the energy deposit per area is
determined from the radio pulses at each observer position and is interpolated
using a two-dimensional function that takes into account signal asymmetries due
to interference between the geomagnetic and charge-excess emission components.
The spatial integral over the signal distribution gives a direct measurement of
the energy transferred from the primary cosmic ray into radio emission in the
AERA frequency range. We measure 15.8 MeV of radiation energy for a 1 EeV air
shower arriving perpendicularly to the geomagnetic field. This radiation energy
-- corrected for geometrical effects -- is used as a cosmic-ray energy
estimator. Performing an absolute energy calibration against the
surface-detector information, we observe that this radio-energy estimator
scales quadratically with the cosmic-ray energy as expected for coherent
emission. We find an energy resolution of the radio reconstruction of 22% for
the data set and 17% for a high-quality subset containing only events with at
least five radio stations with signal.Comment: Replaced with published version. Added journal reference and DO
Measurement of the Radiation Energy in the Radio Signal of Extensive Air Showers as a Universal Estimator of Cosmic-Ray Energy
We measure the energy emitted by extensive air showers in the form of radio
emission in the frequency range from 30 to 80 MHz. Exploiting the accurate
energy scale of the Pierre Auger Observatory, we obtain a radiation energy of
15.8 \pm 0.7 (stat) \pm 6.7 (sys) MeV for cosmic rays with an energy of 1 EeV
arriving perpendicularly to a geomagnetic field of 0.24 G, scaling
quadratically with the cosmic-ray energy. A comparison with predictions from
state-of-the-art first-principle calculations shows agreement with our
measurement. The radiation energy provides direct access to the calorimetric
energy in the electromagnetic cascade of extensive air showers. Comparison with
our result thus allows the direct calibration of any cosmic-ray radio detector
against the well-established energy scale of the Pierre Auger Observatory.Comment: Replaced with published version. Added journal reference and DOI.
Supplemental material in the ancillary file
Recommended from our members
Intestinal microbiome and metabolome signatures in patients with chronic granulomatous disease.
BACKGROUND: Chronic granulomatous disease (CGD) is caused by defects in any 1 of the 6 subunits forming the nicotinamide adenine dinucleotide phosphate oxidase complex 2 (NOX2), leading to severely reduced or absent phagocyte-derived reactive oxygen species production. Almost 50% of patients with CGD have inflammatory bowel disease (CGD-IBD). While conventional IBD therapies can treat CGD-IBD, their benefits must be weighed against the risk of infection. Understanding the impact of NOX2 defects on the intestinal microbiota may lead to the identification of novel CGD-IBD treatments. OBJECTIVE: We sought to identify microbiome and metabolome signatures that can distinguish individuals with CGD and CGD-IBD. METHODS: We conducted a cross-sectional observational study of 79 patients with CGD, 8 pathogenic variant carriers, and 19 healthy controls followed at the National Institutes of Health Clinical Center. We profiled the intestinal microbiome (amplicon sequencing) and stool metabolome, and validated our findings in a second cohort of 36 patients with CGD recruited through the Primary Immune Deficiency Treatment Consortium. RESULTS: We identified distinct intestinal microbiome and metabolome profiles in patients with CGD compared to healthy individuals. We observed enrichment for Erysipelatoclostridium spp, Sellimonas spp, and Lachnoclostridium spp in CGD stool samples. Despite differences in bacterial alpha and beta diversity between the 2 cohorts, several taxa correlated significantly between both cohorts. We further demonstrated that patients with CGD-IBD have a distinct microbiome and metabolome profile compared to patients without CGD-IBD. CONCLUSION: Intestinal microbiome and metabolome signatures distinguished patients with CGD and CGD-IBD, and identified potential biomarkers and therapeutic targets
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