Impact of Sodium Chloride, Sucrose and Milk on Heat Stability of the Murine Norovirus and the MS2 Phage

Until now, little is known about the influence of food additives on heat inactivation of noroviruses. Only a few studies have shown a protective or inhibiting effect on virus infectivity caused by the food matrix. Therefore, the aim of this study was to examine the influence of sodium chloride, sucrose and milk on heat stability of the surrogates murine norovirus (MNV) and MS2 phage at 60 °C for 1–5 min in PBS for MNV and for 5–120 min in suspension medium buffer for MS2 phage. Different concentrations of sodium chloride (5, 10 %) and sucrose (5, 50 %) were added to the respective buffers. In addition, commercially available milk with different fat concentrations (0.3, 1.5, 3.5 %) was investigated in this study. In general, a linear titre reduction for MNV and MS2 phage could be observed, except for the heat treatment of MNV in PBS with 50 % sucrose. A protective effect of PBS with 50 % sucrose and of the matrix milk on MNV could be concluded. All other tested conditions did not show any influence on virus inactivation. However, MS2 phage did show a higher heat resistance throughout the experiments compared to MNV. In future investigations, it should be tested, whether the achieved data may be considered in risk assessments of heat-treated food products with high concentrations of sugar. Furthermore, it should be clarified, whether these results can also be referred to complex food matrices.     

Effect of environmental factors on the effectiveness of ammoniated bagasse in wicking oil from contaminated wetlands

Ammoniated bagasse is a plant-derived organic sorbent that can be used for capturing oil and for supplying slow-release nutrients to oil-degrading microorganisms. We investigated the oil-wicking behavior of this sorbent under various conditions for its effectiveness in remediating oil-contaminated wetlands. Abiotic microcosms simulating a wetland environment were used to assess the influence of sand particle sizes (20× 30 and 60× 80 U.S. mesh), degrees of oil saturation (25% and 75%), water table levels (on top of the clean sand layer, oiled-sand layer, and sorbent layer), and the presence of sorbent. Results indicated that oil wicking favors higher oil contamination, larger sand particle size, and low water coverage. Water coverage was the predominant factor limiting the effectiveness of sorbent. The most plausible explanation for this limitation was that sorbent captured more water than oil at higher water coverage.     

Multi-adsorbent Preconcentration and Gas Chromatographic Analysis of Air Toxics with an Automated Collection/Analytical System

Section 507 of the 1990 Clean Air Act Amendments (CAAA) requires states to develop a small business stationary source and environmental compliance assistance program to aid small businesses impacted by applicable air quality regulations. In general, the program consists of three main components: (1) a small business assistance program (SBAP) for providing compliance and technical assistance to small businesses; (2) an ombudsman for providing direct oversight to the SBAP; and (3) a compliance advisory panel consisting of members from both the public and private sector responsible for determining the overall effectiveness of the SBAP. The key component of the program for assisting small businesses is the SBAP. Providing the necessary assistance to small businesses regarding such issues as permit applicability, rights under the CAAA and emission control options will require the SBAP to develop both proactive and reactive components. The proactive component involves providing outreach services in the form of collecting and disseminating compliance and technical information to small businesses. The reactive component includes the establishment of an information clearinghouse for handling the many inquiries from members of the small business community who have never been subject to air pollution control regulations. States without the available resources to fully implement an SBAP may need to rely on contractor assistance. This paper briefly describes the establishment of the program, provides an overview of each of the program components, discusses many of the ways in which states may implement both the proactive and reactive components of the SBAP, and lists the types of contractors most suitable for SBAP assistance.     

Drastic reduction in the potential habitats for alpine and subalpine vegetation in the Pyrenees due to twenty-first-century climate change

Recent climate change is already affecting both ecosystems and the organisms that inhabit them, with mountains and their associated biota being particularly vulnerable. Due to the high conservation value of mountain ecosystems, reliable science-based information is needed to implement additional conservation efforts in order to ensure their future. This paper examines how climate change might impact on the distribution of the main alpine and subalpine vegetation in terms of losses of suitable area in the Oriental Pyrenees. The algorithm of maximum entropy (Maxent) was used to relate current environmental conditions (climate, topography, geological properties) to present data for the studied vegetation units, and time and space projections were subsequently carried out considering climate change predictions for the years 2020, 2050 and 2080. All models predicted rising altitude trends for all studied vegetation units. Moreover, the analysis of future trends under different climate scenarios for 2080 suggests an average loss in potential ranges of 92.3–99.9 % for alpine grasslands, 76.8–98.4 % for subalpine (and alpine) scrublands and 68.8–96.1 % for subalpine forest. The drastic reduction in the potential distribution areas for alpine grasslands, subalpine scrublands and Pinus uncinata forests highlights the potential severity of the effects of climate change on vegetation in the highest regions of the Pyrenees. Thus, alpine grasslands can be expected to become relegated to refuge areas (summit areas), with their current range being taken over by subalpine scrublands. Furthermore, subalpine forest units will probably become displaced and will occupy areas that currently present subalpine scrub vegetation.     

Comparison of measured total suspended particulate matter concentrations using tapered element oscillating microbalance and a total suspended particulate sampler

A comparison of the concentration of the total suspended particulate (TSP) matter measured by the tapered element oscillating microbalance (TEOM) monitor and the isokinetic TSP samplers developed at the University of Illinois was carried out in several types of confinement livestock buildings. In a majority of the measurements done, the dust concentration measured by the TEOM monitor was lower than the University of Illinois at Urbana-Champaign (UIUC) isokinetic TSP sampler; the TEOM monitor tended to underestimate the total dust concentration by as much as 54%. The difference in measurements can be attributed to the sampling efficiency of the TEOM monitor sampling head and the loss of some semivolatile compounds and particle-bound water because of heating of the TEOM monitor sampling stream to 50 degrees C. Although several articles in the literature supported the latter argument, this study did not investigate the effect of heating the sampling stream or the effect of moisture on the relative difference in dust concentration measurements. The model that best describes the relationship between the two methods was site specific, that is, the linear regression model was applicable only to four of the sites monitored. The measured total dust concentration in livestock buildings range from approximately 300 to 4000 microg/m3; a higher correlation coefficient between TEOM-TSP and UIUC-TSP monitors was obtained in swine facilities than those obtained in a laying facility.     

A survey of organochlorine pesticide residues in cheese samples from three Mexican regions

Organochlorine pesticide residues were determined in cheese samples from three Mexican regions. All samples were found to be contaminated by these residues: p,p'-DDE was present in 100% of the samples. Other pesticides found with high frequencies were HCB, three of the BHC isomers, as well as heptachlor and its epoxide. Also found, although less frequently, were residues of p,p'-DDD, p,p'-DDT, aldrin, dieldrin and endrin. Samples from the region known as Comarca Lagunera had the highest number of pesticides per sample. The highest concentrations of residues were found in cheese samples from the Soconusco and the Comarca Lagunera regions.     

EFFECTIVE USE OF LANDSAT DATA IN HYDROLOGIC MODELS1

ABSTRACT: In a cooperative demonstration project, NASA and the U.S. Army Corps of Engineers (Corps) compared conventional and Landsat-derived land-use data for use in hydrologic models, and the resulting discharge frequency curves were analyzed. When a grid-based data-management system was used on a cell-by-cell basis (size about 1.1 acres or 0.45 hectare), Landsat classification accuracy was only 64 percent, but, when the grid cells were aggregated into watersheds, the classification accuracy increased to about 95 percent. When both conventional and Landsat land-use data were input to the HEC-1 model for generating discharge frequency curves, the differences in calculated discharge were judged insignificant for subbasins as small as 1.0mi² (2.59 km²). For basins larger than 10mi² (25.9km²), use of the Landsat approach is more cost-effective than use of conventional methods. Digital Landsat data can also be used effectively by local and regional agencies for hydrologic analysis by incorporating the data into grid-based data-management systems. The transfer of this new technology is well under way through inclusion in some Corps training courses and through use by both county government personnel and private consultants.     

Adaptive sampling and analysis programs for contaminated soils

Adaptive sampling and analysis programs (ASAPs) provide a cost-effective alternative to traditional sampling program designs. ASAPs are based on field analytical methods for rapid sample turnaround and field-based decision support for guiding the progress of the sampling program. One common objective of ASAPs is to delineate contamination present in soils, either to support feasibility studies or remedial action designs. An ASAP based on portable gas chromatograph/ mass spectrograph (GC/MS) technologies developed at Tufts University combined with decision support tools created at Argonne National Laboratory was used to delineate explosives contamination in soils at Joliet Army Ammunition Plant, Joliet, Illinois. Tufts' GC/MS technologies provided contaminant-specific identification and quantification with rapid sample turnaround and high sample throughput. Argonne's decision support tools estimated contamination extent, determined the uncertainty associated with those estimates, and indicated where sampling should continue to minimize uncertainty. In the case of Joliet, per sample analytical costs were reduced by 75 percent as compared to the cost of off-site laboratory analyses for explosives. The use of an ASAP resulted in a much more accurate identification and delineation of contaminated areas than a traditional sampling program would have with the same number of samples collected on a regular grid. While targeting explosives contamination in soils at Joliet, the ASAP technologies used in this demonstration have much broader application.     

Water Quality Functions of Riparian Forest Buffers in Chesapeake Bay Watersheds

/ Maryland, Virginia, and Pennsylvania, USA, have agreed to reduce nutrient loadings to Chesapeake Bay by 40% by the year 2000. This requires control of nonpoint sources of nutrients, much of which comes from agriculture. Riparian forest buffer systems (RFBS) provide effective control of nonpoint source (NPS) pollution in some types of agricultural watersheds. Control of NPS pollution is dependent on the type of pollutant and the hydrologic connection between pollution sources, the RFBS, and the stream. Water quality improvements are most likely in areas of where most of the excess precipitation moves across, in, or near the root zone of the RFBS. In areas such as the Inner Coastal Plain and Piedmont watersheds with thin soils, RFBS should retain 50%-90% of the total loading of nitrate in shallow groundwater, sediment in surface runoff, and total N in both surface runoff and groundwater. Retention of phosphorus is generally much less. In regions with deeper soils and/or greater regional groundwater recharge (such as parts of the Piedmont and the Valley and Ridge), RFBS water quality improvements are probably much less. The expected levels of pollutant control by RFBS are identified for each of nine physiographic provinces of the Chesapeake Bay Watershed. Issues related to of establishment, sustainability, and management are also discussed.KEY WORDS: Riparian forest buffers; Chesapeake Bay; Nonpoint source pollution; Nitrogen; Phosphorus; Sediment