Survival of Fecal Contamination Indicator Organisms in Soil

Soils amended with human or animal waste may result in pathogen contamination of ground and surface water. Because temperature has been shown to affect pathogen survival, two laboratory studies were conducted to evaluate the impact of extremes in temperature on bacterial and viral pathogen indicator die-off in soil. A Captina silt loam was amended with broiler litter (0.1 g/g dry soil), septic tank effluent, or Escherichia coli (ATCC 13706) culture (both at 0.04 and 0.1 mL/g dry soil in the two respective studies), incubated at 5 and 35°C, and analyzed over time to determine the number of fecal coliform, E. coli, and coliphage remaining. Pathogen indicator die-off rate constants (k) for all indicator- temperature-treatment combinations were determined by first-order kinetics. For all three pathogen indicators, die-off was significantly more rapid at 35°C than at 5°C. In both studies, fecal coliform die-off rates were not different from E. coli die-off rates across each temperature-treatment combination. Levels of these bacterial indicators appeared in a ratio of 1:0.94 with 95% confidence intervals at 0.89 and 0.99 in the E. coli- and litter-amended soils. Die-off of the viral indicator was significantly slower than the die-off of the bacterial indicators at 5°C in litter-amended soil. Die-off of the bacterial indicator, E. coli, in soil amended with E. coli culture was not significantly different than die-off in soil amended with broiler litter at 5 or 35°C in the two studies. Because the higher incubation temperature increased die-off rates for all three indicators, it is expected that the potential for contamination of ground and surface water decreases with increasing temperature

Completion Report: Arkansas State Pesticides in Ground Water Monitoring Project Phase V: Vulnerable areas in Jackson, Monroe, Lawrence and Lonoke Counties

In 1996, sixty-seven water samples were drawn from 65 wells, including 62 new wells and 3 wells sampled previously . One Woodruff County well and two Pulaski County wells were resampled. Thirty-two samples were drawn from 30 wells in Monroe County (well #1 was sampled 3 times during this phase) . Ten wells in Jackson County, 12 wells in Lawrence County and 10 wells in Lonoke were also tested (Figures 1-5) . With the completion of Phase V, the number of wells tested has risen to 231 with a total of 258 samples analyzed . Initially, the wells were tested for 13 pesticides and ni~rate. Two more pesticides, aldicarb and carbofuran were added to the analyte list during Phase V. The analyte list is shown in Table 3 . All results from all the wells are listed in Appendix A. Quality control information for these data follow the results. The Phase V Quality Assurance Report is included in this document as Part II

Full dimensional (15D) quantum-dynamical simulation of the protonated water-dimer I: Hamiltonian setup and analysis of the ground vibrational state

Quantum-dynamical full-dimensional (15D) calculations are reported for the protonated water dimer (H5O2+) using the multiconfiguration time-dependent Hartree (MCTDH) method. The dynamics is described by curvilinear coordinates. The expression of the kinetic energy operator in this set of coordinates is given and its derivation, following the polyspherical method, is discussed. The PES employed is that of Huang et al. [JCP, 122, 044308, (2005)]. A scheme for the representation of the potential energy surface (PES) is discussed which is based on a high dimensional model representation scheme (cut-HDMR), but modified to take advantage of the mode-combination representation of the vibrational wavefunction used in MCTDH. The convergence of the PES expansion used is quantified and evidence is provided that it correctly reproduces the reference PES at least for the range of energies of interest. The reported zero point energy of the system is converged with respect to the MCTDH expansion and in excellent agreement (16.7 cm-1 below) with the diffusion Monte Carlo result on the PES of Huang et al. The highly fluxional nature of the cation is accounted for through use of curvilinear coordinates. The system is found to interconvert between equivalent minima through wagging and internal rotation motions already when in the ground vibrational-state, i.e., T=0. It is shown that a converged quantum-dynamical description of such a flexible, multi-minima system is possible.Comment: 46 pages, 5 figures, submitted to J. Chem. Phy

Effects of Agricultural Practices on Nutrient Concentrations and Loads in Two Small Watersheds, Northwestern Arkansas

The water quality of two small, adjacent watersheds was monitored to determine the effect of land use on nutrient loads and flow-weighted mean concentrations. Poultry litter and liquid swine waste are surface applied as fertilizer to pastures that are used for hay production and beef cattle grazing. The study area is located in northwestern Arkansas, east central Washington County. Cannon Creek, the less influenced watershed (628 hectares), contains 11% pasture; whereas, Shumate Creek, the more influenced watershed (589 hectares), contains 22% pasture and receives approximately four times more land applied animal waste as fertilizer. The remaining land cover in both watersheds is primarily hardwood forest. Shumate Creek lad higher nutrient concentrations and greater nutrient mass transport. Stormflow transports a larger percentage of the nutrient load than baseflow; e.g., during the month of April more than 30% of the total phosphorus (TP) load was transported in less than four days of storm flow at the Shumate Creek site. The total pasture area, the proximity of pastures to streams, and he intensity of pasture management (i.e., the rate and timing of manure applications) are important aspects to consider when monitoring water quality

A Bacillus subtilis cell fraction (BCF) inducing calcium carbonate precipitation: biotechnological perspectives for monumental stone reinforcement

Abstract Monumental stone decay is a consequence of the weathering action of physical, chemical and biological factors, which induce a progressive increase in porosity. To cope this degradation, bacterial calcium carbonate mineralization has been proposed as a tool for the conservation of monumental calcareous stones. The advantage of this kind of treatment is to obtain a mineral product similar to the stone substrate, mimicking the natural process responsible for stone formation. In this work, the possibility to induce CaCO3 mineralization by a bacteria-mediated system in absence of viable cells was investigated and tested on stone. Our results showed that Bacillus subtilis dead cells as wells as its bacterial cell wall fraction (BCF) can act as calcite crystallization nuclei in solution. BCF consolidating capability was further tested in laboratory on slab stones, and in situ on the Angera Church, a valuable 6th century monumental site. New crystals formation was observed inside pores and significant decrease in water absorption (up to 16.7%) in BCF treated samples. A little cohesion increase was observed in the treated area of the Angera Church, showing the potential of this application, even though further improvements are needed

Completion Report: Arkansas State Pesticides in Ground Water Monitoring Project Phase IV: Eastern Arkansas (Pulaski, Lee and Jackson Counties)

In 1995, fifty-two water samples were drawn from 49 new wells and 2 wells that had been previously sampled during earlier phases. These included twenty samples from 19 wells in eastern Pulaski County, thirteen wells in Lee County, 16 wells in Jackson County, two wells in Lonoke County, one well in Crittenden County and resamples of two wells in Woodruff County. Figure 1 shows the locations of the 3 counties where the majority of the samples were taken and Figures 2-4 show the monitoring locations withing these counties. The wells were tested for nitrate and 13 pesticides listed in Table 3. The data and associated quality control information for all the wells tested are included in Section 2: Phase IV Quality Assurance Report

Bowman's layer dystrophy with irido-fundal coloboma in the same patient: a case report

Introduction: The corneal dystrophies are rare corneal diseases, defined as bilateral, symmetric and inherited conditions. Ocular coloboma is a congenital defect caused by embryogenesis imperfection, during the sixth week of development. Purpose: The authors report the first clinical case in literature of the association of cornea dystrophy and irido-fundal coloboma. Case report: The authors describe the case of a 34-year-old woman, with decrease visual acuity (VA) in the right and left eyes (RLE). She has had an ocular illness since young, with corneal erosions. Her family members also have alterations in the cornea, her father has held a bilateral corneal transplant. Ophthalmic examination showed a best-corrected visual acuity (BCVA) of 20/40 in the RE and 20/100 in the LE. Biomicroscopy showed an inferior iris coloboma in the LE. A deposition of reticular/granular substance in the Bowman’s layer was observed in both eyes, sparing the limbal portion, compatible with a corneal dystrophy. Fundus examination showed a coloboma in the LE that involves the inferior retina and the optic nerve, no changes in the RE fundus was observed. She started treatment with ocular lubrificant preservative-free eyedrops. The patient has remained stable within 1-year follow-up. Conclusions: This is the first case report of the association of cornea dystrophy and irido-fundal coloboma. The greater decrease in VA in the LE appears to be due to the combination of these two entities in this eye. Despite the Bowman’s layer dystrophy has an autosomal dominant pattern, coloboma seems to have been an acquired change.info:eu-repo/semantics/publishedVersio