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Approximate Annual Water Budgets of Two Chained Pinyon-Juniper Sites
Approximate annual water budgets for various pinyon-juniper treatments (chaining-with-windrowing, chaining-with-debris-in-place, and natural woodland) have been compiled for a 3-year period near Milford, Utah, and for a 2-year period near Blanding, Utah. Results of the analysis indicate that most of the annual precipitation falling on each treatment is lost through evapotranspiration, with much of the balance being lost through interception. When runoff did occur, it was greatest from windrowed treatments and least from debris-in-place treatments.This material was digitized as part of a cooperative project between the Society for Range Management and the University of Arizona Libraries.The Journal of Range Management archives are made available by the Society for Range Management and the University of Arizona Libraries. Contact [email protected] for further information.Migrated from OJS platform August 202
Diagnosing and mapping pulmonary emphysema on X-ray projection images
To assess whether grating-based X-ray dark-field imaging can increase the sensitivity of X-ray projection images in the diagnosis of pulmonary emphysema and allow for a more accurate assessment of emphysema distribution. Lungs from three mice with pulmonary emphysema and three healthy mice were imaged ex vivo using a laser-driven compact synchrotron X-ray source. Median signal intensities of transmission (T), dark-field (V) and a combined parameter (normalized scatter) were compared between emphysema and control group. To determine the diagnostic value of each parameter in differentiating between healthy and emphysematous lung tissue, a receiver-operating-characteristic (ROC) curve analysis was performed both on a per-pixel and a per-individual basis. Parametric maps of emphysema distribution were generated using transmission, dark-field and normalized scatter signal and correlated with histopathology. Transmission values relative to water were higher for emphysematous lungs than for control lungs (1.11 vs. 1.06, p<0.001). There was no difference in median dark-field signal intensities between both groups (0.66 vs. 0.66). Median normalized scatter was significantly lower in the emphysematous lungs compared to controls (4.9 vs. 10.8, p<0.001), and was the best parameter for differentiation of healthy vs. emphysematous lung tissue. In a per-pixel analysis, the area under the ROC curve (AUC) for the normalized scatter value was significantly higher than for transmission (0.86 vs. 0.78, p<0.001) and dark-field value (0.86 vs. 0.52, p<0.001) alone. Normalized scatter showed very high sensitivity for a wide range of specificity values (94% sensitivity at 75% specificity). Using the normalized scatter signal to display the regional distribution of emphysema provides color-coded parametric maps, which show the best correlation with histopathology. In a murine model, the complementary information provided by X-ray transmission and dark-field images adds incremental diagnostic value in detecting pulmonary emphysema and visualizing its regional distribution as compared to conventional X-ray projections
Revisiting the distribution of oceanic N<sub>2</sub> fixation and estimating diazotrophic contribution to marine production
Marine N2 fixation supports a significant portion of oceanic primary production by making N2 bioavailable to planktonic communities, in the process influencing atmosphere-ocean carbon fluxes and our global climate. However, the geographical distribution and controlling factors of marine N2 fixation remain elusive largely due to sparse observations. Here we present unprecedented high-resolution underway N2 fixation estimates across over 6000 kilometers of the western North Atlantic. Unexpectedly, we find increasing N2 fixation rates from the oligotrophic Sargasso Sea to North America coastal waters, driven primarily by cyanobacterial diazotrophs. N2 fixation is best correlated to phosphorus availability and chlorophyll-a concentration. Globally, intense N2 fixation activity in the coastal oceans is validated by a meta-analysis of published observations and we estimate the annual coastal N2 fixation flux to be 16.7 Tg N. This study broadens the biogeography of N2 fixation, highlights the interplay of regulating factors, and reveals thriving diazotrophic communities in coastal waters with potential significance to the global nitrogen and carbon cycles
Complex network analysis of wind tunnel experiments on the passive scalar dispersion in a turbulent boundary layer
In this work, data of passive scalar plumes in a turbulent boundary layer are investigated. The experiments are performed in a wind tunnel where a passive scalar is injected through an L-shaped tube. Two source configurations are analysed for two different tube diameters. The passive scalar concentration is then measured at different distances from the source and wall-normal locations. By exploiting the recent advances of complex networks theory, the concentration time-series are mapped into networks, through the visibility algorithm. The resulting networks inherit the temporal features of the mapped time-series, revealing non-trivial information about the underlying transport process. This work represents an example of the great potentialities of the complex network approach for the analysis of turbulent transport and mixing.</p
The HIV-1 Subtype C Epidemic in South America Is Linked to the United Kingdom
Background: The global spread of HIV-1 has been accompanied by the emergence of genetically distinct viral strains. Over the past two decades subtype C viruses, which predominate in Southern and Eastern Africa, have spread rapidly throughout parts of South America. Phylogenetic studies indicate that subtype C viruses were introduced to South America through a single founder event that occurred in Southern Brazil. However, the external route via which subtype C viruses spread to the South American continent has remained unclear.Methodology/Principal Findings: We used automated genotyping to screen 8,309 HIV-1 subtype C pol gene sequences sampled within the UK for isolates genetically linked to the subtype C epidemic in South America. Maximum likelihood and Bayesian approaches were used to explore the phylogenetic relationships between 54 sequences identified in this screen, and a set of globally sampled subtype C reference sequences. Phylogenetic trees disclosed a robustly supported relationship between sequences from Brazil, the UK and East Africa. A monophyletic cluster comprised exclusively of sequences from the UK and Brazil was identified and dated to approximately the early 1980s using a Bayesian coalescent-based method. A sub-cluster of 27 sequences isolated from homosexual men of UK origin was also identified and dated to the early 1990s.Conclusions: Phylogenetic, demographic and temporal data support the conclusion that the UK was a crucial staging post in the spread of subtype C from East Africa to South America. This unexpected finding demonstrates the role of diffuse international networks in the global spread of HIV-1 infection, and the utility of globally sampled viral sequence data in revealing these networks. Additionally, we show that subtype C viruses are spreading within the UK amongst men who have sex with men
A Multi-Wavelength Mass Analysis of RCS2 J232727.6-020437, a ~3x10M Galaxy Cluster at z=0.7
We present an initial study of the mass and evolutionary state of a massive
and distant cluster, RCS2 J232727.6-020437. This cluster, at z=0.6986, is the
richest cluster discovered in the RCS2 project. The mass measurements presented
in this paper are derived from all possible mass proxies: X-ray measurements,
weak-lensing shear, strong lensing, Sunyaev Zel'dovich effect decrement, the
velocity distribution of cluster member galaxies, and galaxy richness. While
each of these observables probe the mass of the cluster at a different radius,
they all indicate that RCS2 J232727.6-020437 is among the most massive clusters
at this redshift, with an estimated mass of M_200 ~3 x10^15 h^-1 Msun. In this
paper, we demonstrate that the various observables are all reasonably
consistent with each other to within their uncertainties. RCS2 J232727.6-020437
appears to be well relaxed -- with circular and concentric X-ray isophotes,
with a cool core, and no indication of significant substructure in extensive
galaxy velocity data.Comment: 19 pages, 15 figures, submitted to ApJ on March 5, 2015; in press.
Manuscript revised following the referee revie
Solving the riddle of the bright mismatches: hybridization in oligonucleotide arrays
HDONA technology is predicated on two ideas. First, the differential between
high-affinity (perfect match, PM) and lower-affinity (mismatch, MM) probes is
used to minimize cross-hybridization. Second, several short probes along the
transcript are combined, introducing redundancy. Both ideas have shown problems
in practice: MMs are often brighter than PMs, and it is hard to combine the
pairs because their brightness often spans decades. Previous analysis suggested
these problems were sequence-related; publication of the probe sequences has
permitted us an in-depth study of this issue. Our results suggest that
fluorescently labeling the nucleotides interferes with mRNA binding, causing a
catch-22 since, to be detected, the target mRNA must both glow and stick to its
probe: without labels it cannot be seen even if bound, while with too many it
won't bind. We show that this conflict causes much of the complexity of HDONA
raw data, suggesting that an accurate physical understanding of hybridization
by incorporating sequence information is necessary to perfect microarray
analysis.Comment: 4 figure
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