Foliar damage to ornamental trees sprinkler-irrigated with reuse water

The extent of foliar damage to ornamental trees irrigated with treated sewage effluent (reuse water) may be a significant factor dictating the extent of reuse water implementation on golf courses, schools and parks in the arid southwestern United States. An experiment was conducted on 20 tree species to determine the extent of foliar damage when sprinkler-irrigated with reuse water, municipal water or a synthesized saline water. Irrigations (168) were applied over a 16-month period via 183-cm raised sprinkler heads, to plots that contained the trees in a dual-pot system. Plant water status, growth, tissue ion concentrations and an index of visual damage (IVD) were assessed at different times throughout the experiment. A higher IVD (greater foliar damage) was reported for most species when sprinkler-irrigated with either reuse or synthesized saline water. However, six species showed significant foliar damage even when irrigated with municipal water. The accumulation of Cl in the tissue was shown to be a species-dependent response, with tissue Cl concentrations varying by as much as a factor of 5. When a backward stepwise multiple regression analysis was conducted on the normalized (reuse-municipal) IVD and tissue ion concentrations, all ions except Na were eliminated from the correlation (Index (reuse - municipal)=0.79+0.62Na (reuse - municipal), r=0.72***, n=20). Wax content on the leaves in the reuse (0.310 mg cm^-2) and saline treatments (0.546 mg cm^-2) and the increase in wax content with time (young leaves/May vs mature leaves/July) suggested a possible stress response. Based on the results of this experiment, we believe the number of woody ornamental trees that can tolerate spray irrigation of reuse water in the hot dry environment of southern Nevada to be limited.     

Electron small polarons and their mobility in iron (oxyhydr)oxide nanoparticles

Electron mobility within iron (oxyhydr)oxides enables charge transfer between widely separated surface sites. There is increasing evidence that this internal conduction influences the rates of interfacial reactions and the outcomes of redox-driven phase transformations of environmental interest. To determine the links between crystal structure and charge-transport efficiency, we used pump-probe spectroscopy to study the dynamics of electrons introduced into iron(III) (oxyhydr)oxide nanoparticles via ultrafast interfacial electron transfer. Using time-resolved x-ray spectroscopy and ab initio calculations, we observed the formation of reduced and structurally distorted metal sites consistent with small polarons. Comparisons between different phases (hematite, maghemite, and ferrihydrite) revealed that short-range structural topology, not long-range order, dominates the electron-hopping rate.     

Sorghum Phenolics Inhibits Inflammasomes in Lipopolysaccharide (LPS)-Primed and Adenosine Triphosphate (ATP)-Activated Macrophages

Plant Foods for Human Nutrition - Sorghum contains phenolic compounds with reported biological activities. The objective was to evaluate the ability of sorghum phenolic extract to inhibit...     

Within and between-field spatial variation in soil phosphorus in permanent grassland

Soil phosphorus (P) concentrations above certain critical thresholds are a problem in many areas leading to its transport into surface and ground waters. Site-specific nutrient applications and the development of nutrient management plans for farms would help to optimize nutrient applications, meet crop requirements and take into consideration current soil nutrient status. In Northern Ireland, high concentrations of soil P are common, whereas low concentrations of soil potassium (K) and sulphur (S) have been reported in many silage fields. This study used grid and transect soil sampling to measure within- and between-field spatial variation in soil Olsen-P status across a 50-ha permanent grassland site used for silage production. Soil phosphorus indices ranged from Index 1 to Index 4 within single fields. The spatial patterns of soil P across fields suggested that there was scope for site-specific P fertilizer applications, with variable quantities of P being applied to different fields and within individual fields. Site-specific nutrient management has the potential to reduce excess P applications in some areas and avoid deficiencies in others, thereby minimizing environmental problems and optimizing yield.     

Using patterns of reef fish assemblages to refine a Habitat Classification System for marine parks in NSW,Australia

• 1. The Solitary Islands Marine Park (SIMP) in New South Wales (NSW), Australia, is located in a tropical‐temperate biotone, with variable influence of the tropical East Australian Current (EAC) from inshore to offshore. Marine communities on the extensive, subtidal, rocky reefs are poorly described. As a result, the current Habitat Classification System (HCS) used as part of the process to determine the marine park zoning arrangements, which places all shallow reef (<25 m) in the same category, is unlikely to represent real biotic patterns.
• 2. To evaluate the influence of five key factors (distance from shore, reef type, dominant benthos, latitude, and depth range) fish assemblages were widely surveyed, using 30‐minute timed counts, at 68 sites across the extent of shallow reef within the park. Relationships between assemblage patterns and levels of the different factors were subsequently examined using multivariate analyses.
• 3. Patterns of reef fish assemblages were most strongly correlated with distance from shore. Three distinct assemblages occurred on inshore (<1.5 km), mid‐shelf (1.5–6 km), and offshore (>6 km) reefs. Differences in assemblage structure by reef type were also apparent on inshore and offshore reefs, but not on mid‐shelf reefs. Correlations with the other factors were weak. The cross‐shelf pattern was persistent over the scale of years.
• 4. The results of the study provide strong support for incorporating distance‐from‐shore categories into a refined HCS. This will improve its ability to represent biological diversity as reflected by patterns of reef fish assemblages. Further research is required to determine the wider application of the HCS to other marine parks in NSW and to determine if it also, effectively, represents other components of biodiversity. Copyright © 2009 John Wiley & Sons, Ltd.

     

Comparative study of serological methods for the detection of antibodies to porcine reproductive and respiratory syndrome virus.

A comparison was made of serological diagnostic methods used for the detection of antibodies against porcine reproductive and respiratory syndrome (PRRS) virus. In the "phase I" PRRS test panel comparison, a panel of sera collected from 135 pigs of various ages, from North American herds with and without PRRS histories, were sent to 4 different laboratories and tested by an indirect immunofluorescent assay (IFA), an immunoperoxidase monolayer assay (IPMA) and an indirect enzyme-linked immunosorbent assay (iELISA). In the "phase II" PRRS test panel comparison, a panel of 382 sera collected from pigs of various ages, PRRS histories, and from various locations in North America and France, were divided into 2 panels (A & B) and sent to 3 Canadian laboratories and tested by the IFA and iELISA. In the phase I comparison, agreement between the IFA of laboratory 4 and the iELISA and IPMA of laboratory 3 was excellent (kappa values of 95% and 98%, respectively). This contrasted with the poor agreement between these laboratories and the IFA results of laboratories 1 and 2 in the phase I trial. In the phase II comparison, the results demonstrated good agreement between various tests both within and between laboratories. The overall performance of the iELISA was superior in the combination of sensitivity (96.1%) and specificity (100%) relative to the reference classification of the serum samples and repeatability (kappa value 98%). The iELISA is technically superior to IFA and IPMA, time efficient, cost effective and suitable for testing of a large number of samples over a short period of time. Thus, the iELISA may be a better alternative to IFA or IPMA for routine detection of PRRS viral antibodies in swine sera.     

Interactions between commensal fungi and the C-type lectin receptor Dectin-1 influence colitis

The intestinal microflora, typically equated with bacteria, influences diseases such as obesity and inflammatory bowel disease. Here, we show that the mammalian gut contains a rich fungal community that interacts with the immune system through the innate immune receptor Dectin-1. Mice lacking Dectin-1 exhibited increased susceptibility to chemically induced colitis, which was the result of altered responses to indigenous fungi. In humans, we identified a polymorphism in the gene for Dectin-1 (CLEC7A) that is strongly linked to a severe form of ulcerative colitis. Together, our findings reveal a eukaryotic fungal community in the gut (the "mycobiome") that coexists with bacteria and substantially expands the repertoire of organisms interacting with the intestinal immune system to influence health and disease.     

Evolution and functional impact of rare coding variation from deep sequencing of human exomes

As a first step toward understanding how rare variants contribute to risk for complex diseases, we sequenced 15,585 human protein-coding genes to an average median depth of 111× in 2440 individuals of European (n = 1351) and African (n = 1088) ancestry. We identified over 500,000 single-nucleotide variants (SNVs), the majority of which were rare (86% with a minor allele frequency less than 0.5%), previously unknown (82%), and population-specific (82%). On average, 2.3% of the 13,595 SNVs each person carried were predicted to affect protein function of ~313 genes per genome, and ~95.7% of SNVs predicted to be functionally important were rare. This excess of rare functional variants is due to the combined effects of explosive, recent accelerated population growth and weak purifying selection. Furthermore, we show that large sample sizes will be required to associate rare variants with complex traits.