Convergence in Nitrogen Deposition and Cryptic Isotopic Variation Across Urban and Agricultural Valleys in Northern Utah

The extent to which atmospheric nitrogen (N) deposition reflects land use differences and biogenic versus fossil fuel reactive N sources remains unclear yet represents a critical uncertainty in ecosystem N budgets. We compared N concentrations and isotopes in precipitation-event bulk (wet + dry) deposition across nearby valleys in northern Utah with contrasting land use (highly urban versus intensive agriculture/low-density urban). We predicted greater nitrate (NO3−) versus ammonium (NH4+) and higher δ15N of NO3− and NH4+ in urban valley sites. Contrary to expectations, annual N deposition (3.5–5.1 kg N ha−1 yr−1) and inorganic N concentrations were similar within and between valleys. Significant summertime decreases in δ15N of NO3− possibly reflected increasing biogenic emissions in the agricultural valley. Organic N was a relatively minor component of deposition (~13%). Nearby paired wildland sites had similar bulk deposition N concentrations as the urban and agricultural sites. Weighted bulk deposition δ15N was similar to natural ecosystems (−0.6 ± 0.7‰). Fine atmospheric particulate matter (PM2.5) had consistently high values of bulk δ15N (15.6 ± 1.4‰), δ15N in NH4+ (22.5 ± 1.6‰), and NO3− (8.8 ± 0.7‰), consistent with equilibrium fractionation with gaseous species. The δ15N in bulk deposition NH4+ varied by more than 40‰, and spatial variation in δ15N within storms exceeded 10‰. Sporadically high values of δ15N were thus consistent with increased particulate N contributions as well as potential N source variation. Despite large differences in reactive N sources, urban and agricultural landscapes are not always strongly reflected in the composition and fluxes of local N deposition—an important consideration for regional-scale ecosystem models

An optical method for carbon dioxide isotopes and mole fractions in small gas samples: Tracing microbial respiration from soil, litter, and lignin

Rationale Carbon dioxide isotope (δ13C value) measurements enable quantification of the sources of soil microbial respiration, thus informing ecosystem C dynamics. Tunable diode lasers (TDLs) can precisely measure CO2 isotopes at low cost and high throughput, but are seldom used for small samples (≤5 mL). We developed a TDL method for CO2 mole fraction ([CO2]) and δ13C analysis of soil microcosms. Methods Peaks in infrared absorbance following constant volume sample injection to a carrier were used to independently measure [12CO2] and [13CO2] for subsequent calculation of δ13C values. Using parallel soil incubations receiving differing C substrates, we partitioned respiration from three sources using mixing models: native soil organic matter (SOM), added litter, and synthetic lignin containing a 13C label at Cβ of the propyl side chain. Results Once-daily TDL calibration enabled accurate quantification of δ13C values and [CO2] compared with isotope ratio mass spectrometry (IRMS), with long-term external precision of 0.17 and 0.31‰ for 5 and 1 mL samples, respectively, and linear response between 400 and 5000 μmol mol−1CO2. Production of CO2 from native soil C, added litter, and lignin Cβ varied over four orders of magnitude. Multiple-pool first-order decay models fitted to data (R2 \u3e 0.98) indicated substantially slower turnover for lignin Cβ (17 years) than for the dominant pool of litter (1.3 years) and primed soil C (3.9 years). Conclusions Our TDL method provides a flexible, precise, and high-throughput (60 samples h−1) alternative to IRMS for small samples. This enables the use of C isotopes in increasingly sophisticated experiments to test biogeochemical controversies, such as the fate of lignins in soil

The Movement To Cyberbanking

Five hundred financial institutions in the United States are randomly sampled each year in order to examine Internet participation present and planned by the financial institutions. Each year CEOs of selected institutions are asked about the institution’s present involvement with on?line banking and their internet plans for the next two years. The usable response rates achieved in these studies have exceeded 40 percent. This paper examines the responses for the year 2001

Hydraulic Model Database for Applicated Distribution Systems Research

Hypothetical and simplified models have been essential to the momentous work of the last 50 years in water distribution systems analysis. However, as researchers continue to improve the way water distribution systems are modeled and analyzed with advancements in technology, it is imperative that the research community has access to a variety of hydraulic datasets that are more representative of real systems and offer a wide range of operating conditions for algorithm development and evaluation. At the 2013 World Environmental and Water Resources Congress in Cincinnati, Ohio, the ASCE Task Committee on Research Databases for Water Distribution Systems was formed with the purpose of developing an online, open access repository of water distribution system hydraulic model files for use in applied scientific research. The current database has been updated and migrated to the University of Kentucky’s UKnowledge web portal which serves as an online repository of research which is freely accessible to the public and maintained by University of Kentucky library. Over the last few years, KWRRI staff have developed narratives for each system that include a primary contributor, a schematic of the system, a model description, a brief history of each system, and a link to a list of publications that have referenced or used the model. Additionally, each narrative contains a table that lists basic system properties such as the maximum daily demand and the number of pipes, junctions, tanks, reservoirs, pumps, valves, hydrants, customers, and water meters. Additional classification metrics (e.g., grid, loop, or branch system) have also been provided. The current database is divided into eight basic datasets and includes: • Historic literature datasets (both hypothetical and skeletonized real-world systems). • Historic software user manual examples from KYPIPE and EPANET. • Models used in “Battle of Networks” competitions. • The Kentucky dataset. • The Kentucky valve dataset. • Models of components of several US Cities. • Models of components of several International Cities. • Synthetic Systems. Detailed statistics about each system are provided in the Table of Database Systems

CMB Signals of Neutrino Mass Generation

We propose signals in the cosmic microwave background to probe the type and spectrum of neutrino masses. In theories that have spontaneous breaking of approximate lepton flavor symmetries at or below the weak scale, light pseudo-Goldstone bosons recouple to the cosmic neutrinos after nucleosynthesis and affect the acoustic oscillations of the electron-photon fluid during the eV era. Deviations from the Standard Model are predicted for both the total energy density in radiation during this epoch, \Delta N_nu, and for the multipole of the n'th CMB peak at large n, \Delta l_n. The latter signal is difficult to reproduce other than by scattering of the known neutrinos, and is therefore an ideal test of our class of theories. In many models, the large shift, \Delta l_n \approx 8 n_S, depends on the number of neutrino species that scatter via the pseudo-Goldstone boson interaction. This interaction is proportional to the neutrino masses, so that the signal reflects the neutrino spectrum. The prediction for \Delta N_nu is highly model dependent, but can be accurately computed within any given model. It is very sensitive to the number of pseudo-Goldstone bosons, and therefore to the underlying symmetries of the leptons, and is typically in the region of 0.03 < \Delta N_nu < 1. This signal is significantly larger for Majorana neutrinos than for Dirac neutrinos, and, like the scattering signal, varies as the spectrum of neutrinos is changed from hierarchical to inverse hierarchical to degenerate.Comment: 40 pages, 4 figure

Routine Screening of Adolescents for Trichomonas vaginalis in a Juvenile Detention Center

Background: Detained and incarcerated adolescents are at increased risk of sexually transmitted infections (STI), but limited information is currently available regarding the prevalence of Trichomonas vaginalis (TV) in detained youth.Methods: A total of 144 detainees (75 males and 69 females) in the Franklin County Juvenile Detention Facility (FCJDF) in Columbus, Ohio, consented to STI screening between May 2016 and June 2017. Participants were screened for TV in addition to Neisseria gonorrhoeae (NG) and Chlamydia trachomatis (CT) using urine nucleic acid amplification tests (NAAT).Results: Among detained youth who consented to testing, TV was identified in 7 of 69 (10.1%) females and 0 of 75 (0%) males (P &lt;0.01). Neisseria gonorrhoeae was identified in 12 of 69 (17.4%) females and 3 of 75 (4.0%) males (P = 0.01), and CT was identified in 16 of 69 (23.2%) female and 7 of 75 (9.3%) male detainees (P = 0.04). Among females, positive TV screen was associated with prior history of STI.Conclusion: Our data support routine screening of female detainees at FCJDF, based on our finding of 10% posi-tivity among females who underwent testing

Multitemporal Snow Cover Mapping in Mountainous Terrain for Landsat Climate Data Record Development

A multitemporal method to map snow cover in mountainous terrain is proposed to guide Landsat climate data record (CDR) development. The Landsat image archive including MSS, TM, and ETM+ imagery was used to construct a prototype Landsat snow cover CDR for the interior northwestern United States. Landsat snow cover CDRs are designed to capture snow-covered area (SCA) variability at discrete bi-monthly intervals that correspond to ground-based snow telemetry (SNOTEL) snow-water-equivalent (SWE) measurements. The June 1 bi-monthly interval was selected for initial CDR development, and was based on peak snowmelt timing for this mountainous region. Fifty-four Landsat images from 1975 to 2011 were preprocessed that included image registration, top-of-the-atmosphere (TOA) reflectance conversion, cloud and shadow masking, and topographic normalization. Snow covered pixels were retrieved using the normalized difference snow index (NDSI) and unsupervised classification, and pixels having greater (less) than 50% snow cover were classified presence (absence). A normalized SCA equation was derived to independently estimate SCA given missing image coverage and cloud-shadow contamination. Relative frequency maps of missing pixels were assembled to assess whether systematic biases were embedded within this Landsat CDR. Our results suggest that it is possible to confidently estimate historical bi-monthly SCA from partially cloudy Landsat images. This multitemporal method is intended to guide Landsat CDR development for freshwaterscarce regions of the western US to monitor climate-driven changes in mountain snowpack extent