Effect of Mussel��s Gender and Size on a Stress Response Biomarker

In mussels, stress signals such as heat, osmotic shock and hypoxia lead to the activation of the phosphorylated p38 mitogen activated protein kinase (pp38-MAPK). This stress activated protein has been efficiently used as a biomarker to several natural and anthropogenic stresses. However, what has not been tested is whether differences in gender or size can affect the response of this biomarker. The present study tested whether there was variation in the expression of pp38-MAPK in mussels Perna perna of different gender and size classes when exposed to natural stress conditions, such as air exposure. The results show that gender does not affect the expression of pp38-MAPK. However, size does have an effect, where mussels smaller than 6.5 cm displayed significantly (p?<?0.05) lower levels of pp38-MAPK when compared to those larger than 7 cm. Mussels are one of the most used bioindicator species and the use of biomarkers to determine the health status of an ecosystem has been greatly increasing over the years. The present study highlights the importance of using mussels of similar size classes when performing experiments using stress-related biomarkers.     

Dynamics of Atmospheric Aerosol Number Size Distributions in the Eastern Mediterranean During the ��SUB-AERO�� Project

Measurements of number size distributions of submicron aerosols have been performed at the Eastern part of Mediterranean as part of an extensive measurement campaign to study photo-oxidants and aerosols (SUB-AERO Project). The measurements were made at the Finokalia station on the island of Crete (Greece) and onboard the research vessel ??Aegaeon??. Two campaigns were performed during July 2000 and January 2001 using two scanning mobility particle sizers. The particle distributions measured in the range between 7.8 < d _p < 327 nm during the summer measurements and between 7.5 < d _p < 316 nm during the winter measurements, where d _p is the mobility particle diameter. The concentration of ultrafine particles (7.5 < d _p < 30 nm) was higher during the winter period and varied mainly between 5 × 10¹ and 2 × 10³?cm^?3 with concentration peak values for this mode exceeding 1 × 10⁴?cm^?3. During the summer campaign, an average number concentration of 1 × 10²?cm^?3 at Finokalia and about 5 × 10¹?cm^?3 aboard the ??Aegaeon?? vessel was measured. An average concentration of 1 × 10³?cm^?3 was measured for the particles in the size range between 30 and 100 nm, whereas in the size range 100?C300 nm, the measured concentration ranged between 1 × 10² and 5 × 10³?cm^?3. Diurnal patterns in number concentrations were observed in connection with the transport of air masses and local sources. During the winter period, three nucleation events were observed in connection with the appearance of a particle mode at 20 nm.     

Bioremediation of a Soil Industrially Contaminated by Wood Preservatives��Degradation of Polycyclic Aromatic Hydrocarbons and Monitoring of Coupled Arsenic Translocation

Two commercially available aerobic bioremediation methods (Daramend® and BioSan) were utilized to study the aerobic biodegradation of polycyclic aromatic hydrocarbons (PAH) and the effect of the simultaneously present arsenic. The soil was collected at an old wood preservation site, and the initial PAH₁₆-concentration was 46 mg/kg, with mainly high molecular weight congeners. The As concentration was 105 mg/kg with low availability as assessed with sequential extraction. To enhance the availability of PAH, the effect of a nonionic surfactant was evaluated. Degradation of both low and high molecular weight PAH was observed; however, after 30 weeks, the degradation was generally low and no treatment was significantly better than the others. The treatments had, on the other hand, an effect on As remobilization, with increased As concentration in the available fraction after treatment. This may be due to both the microbial activity and the presence of anoxic microsites in the soil. The overall efficiency of the biological treatment was further evaluated using the standardized ecotoxicity test utilizing Vibrio fischeri (Microtox®). The toxicity test demonstrated that the bioremediation led to an increase in toxicity, especially in treatments receiving surfactant. The surfactant implied an increase in contaminant availability but also a decrease in surface tension, which might have contributed to the overall toxicity increase.     

Sorption of Selected Aromatic Substances��Application of Kinetic Concepts and Quantum Mechanical Modeling

Prediction of the sorption behavior of environmental pollutants is of utmost importance within the framework of risk assessments. In this work two approaches are presented with the aim to describe sorption of aromatic substances to geosorbents. First, analytical solutions of kinetic models were fitted to experimental data of batch sorption experiments with aniline and 1-naphthylamine onto animal manure-treated soil and the soil mineral montmorillonite. The models, accounting for equilibrium and nonequilibrium sorption coupled to transformation and/or irreversible sorption processes, could well reproduce the concentration course of the sorbates. Results suggest that the amounts transformed/degraded and irreversibly bound were higher for the soil than for the clay mineral. In the second part, quantum chemical calculations were performed on aniline and 1-naphthylamine interacting with acetic acid, acetamide, imidazole, and phenol as models of functional groups present in humic substances. Molecular modeling showed that formation of hydrogen bonds is the dominating binding mechanism in all modeled complexes, which are energetically very similar between aniline and 1-naphthylamine.     

Irrigation,a productive tool for food security – a review

Water scarcity in agriculture is becoming a major problem due to increasing demand from nonagricultural uses and intensive crop management on existing croplands to meet the needs of an expanding global population. Efficient use of the available irrigation water is therefore of important concern. Even though intensive research in the areas of crop physiology, irrigation engineering, agronomy and agricultural economics has developed several ways to improve the efficiency of irrigation water, a multidisciplinary approach is often regarded as the best future path to achieve further enhancements in meeting the forthcoming challenge of producing more and safety foods. Failure of irrigation production has profound effects on the welfare of all those employed in it and also their customers. Indeed, the scale of the industry is such that world food prices will be influenced by the overall performance of the irrigation farmers, but low food prices are essential to the welfare of the poorest people. The contribution of irrigation and water management to increased food production must come through both expansion of irrigation and improved management of existing water supplies. This review presents the past, current and future panorama of irrigation as a viable tool in ensuring food security on the globe. Considering past trends, this review empathizes that future irrigation technologies should be focused on providing the leadership and capacity to capture, develop and promote new irrigation practices and management systems to optimize production.     

Organic Carbon Dynamics along a Toposequence in a Peri‐urban Site

Abstract

The pattern of carbon (C) storage in soils has implications for agriculture and the environment. Dynamics of organic C, in the 0‐ to 20‐cm soil depth along a toposequence in a peri urban site in Sierra Leone, West Africa, were studied. Organic C was determined by the dry‐combustion method on the following aggregate size fractions: whole soil (<2000 µm), 250–2000 µm, 53–250 µm, and <53 µm.

Mean organic C content of whole soil ranged from 4.8% on the backslope to 9.3% on the toeslope. Organic C content of aggregate size fractions increased with decreasing aggregate size. The amount of soil and organic C present in aggregate size fractions, at all positions on the toposequence, decreased with decreasing aggregate size. In general, convex upper slopes had lower contents and amounts of organic C compared to lower concave areas. This study provided benchmark levels and patterns against which changes resulting from imminent urbanization can be measured.     

How well does a botanical garden collection of a rare palm capture the genetic variation in a wild population?

Conservation is increasingly central to the botanic garden mission. Living plant collections are important components of conservation. Critical evaluation of living conservation collections with population genetic analysis can directly inform ex situ conservation strategy. Here, we quantify the degree of genetic variation captured through a population-based collection protocol, and explore optimal sampling for ex situ conservation. An extensive living collection derived from one population of Leucothrinax morrisii (Arecaceae) provided a model system. We compared 58 specimens from the ex situ collection with 100 individuals from throughout the parent population via 6 ISSR loci. Random bootstrapped resamples of the data were made to model differently structured ex situ collections. Mean diversity (He) differed little between the collection (0.204) and the population (0.216), and genetic distance (D) was very close (0.036). Very few private alleles were found between the collection and the population. Allelic capture, as measured by percent of private alleles, was greater than 94%. Resampled collections of different sizes captured from 48% to 94% of alleles. Pairwise comparison of bootstrapped resamples suggests that increasing the representation of half-sibling groups does not significantly increase allele capture. Increase in allele capture with increasing sample size is greatest at low resample sizes, and showed diminishing returns as resample size increased. No appreciable increase in allele capture was gained through maintaining different half-sibling groups. These data inform sampling for ex situ conservation purposes, and recommend sample sizes of at least 15 individuals, with the upper limit based on resources.     

DDT in Biota of Paranagu�� Bay, Southern Brazil: Recent Input and Rapid Degradation

The presence of recent dichlorodiphenyltrichloroethane (DDT) inputs is established for Paranaguá Bay biota, i.e. bivalves, fish and one sponge. Values ranged from 6.9 to 156.2 ng ??DDT/g dry weight. Three fish species analysed showed ??DDT values from 36.8 to 92.1 ng/g dry weight. The highest contents (up to 156.2 ng ??DDT/g dry weight) were found for mangrove oysters (Crassostrea rhizophorae) at locations affected by sewage discharge from Paranaguá City. Turtles as herbivores were not affected by this input with values of 0.7 and 2.2 ng ??DDT/g dry weight. The areal distribution of samples suggests that usage of DDT is widespread around the bay. Fresh DDT input is degraded to DDE and DDD within approximately 5 months.     

Natural product chemistry meets genetics: when is a genotype a chemotype?

The chemotype of a microbial or plant species has traditionally been defined as its profile of natural products, and the genotype has been defined as its genetic constitution or DNA sequence. The purpose of this perspective is to discuss applications of DNA genotyping, particularly by polymerase chain reaction (PCR)-amplification methods, to predicting natural product chemotypes of fungi and plants of importance in food and agriculture. Development of PCR genotyping for predicting chemotypes will require collaboration between molecular biologists and natural product chemists, as well as community standards for reporting data. PCR genotyping should be validated by chemical analysis of individuals that represent the allelic diversity of the target gene in the population. To avoid misinterpretation, it is critical to differentiate data obtained by genotyping from data obtained by chemical analysis. The obvious and appropriate solution is to retain the established meanings of genotype and chemotype, both of which have been in use for half a century in the fields of genetics and natural product chemistry.     

“double bunch” in a plantain germplasm in Nigeria: a new Genotype

In the course of germplasm exploratory work, a strain of a False Horn plantain cultivar was found which produced two bunches at fruiting. Cropping of the suckers of this material through three cycles showed that all the plants studied, produced two bunches of fruits. The results suggest that this plantain tentatively designated as double bunch, is of genetic origin arising probably from a mutation of the existing plantain cultivar. The implications for the identification of genetic diversity as well as for the evaluation and conservation of genetic resources are discussed.     

Breakfast eating and overweight in a pre-school population: is there a link?

OBJECTIVES: To analyse the socio-economic factors related to breakfast eating, the association between breakfast eating and overweight, and to gain a more thorough understanding of the relationship between these two elements in a population-based cohort of 4.5-year-old children. We hypothesised that a relationship could be observed between breakfast skipping and overweight independently of socio-economic factors such as ethnicity, maternal education, single parenting and family income. DESIGN: A population-based study whereby standardised nutritional interviews were conducted with each child's parent. The children's height and weight were taken by a trained nutritionist and parents were asked about their child's breakfast eating. SETTING: The analyses were performed using data from the Québec Longitudinal Study of Child Development (1998-2002), conducted by Santé Québec (Canada). SUBJECTS: Subjects were 1549 children between the ages of 44 and 56 months, with a mean age of 49 months. RESULTS: Almost a tenth (9.8%) of the children did not eat breakfast every day. A greater proportion of children with immigrant mothers (19.4% vs. 8.3% from non-immigrant mothers), with mothers with no high school diploma (17.5% vs. <10% for higher educated mothers) and from low-income families (15% for income of $39,999 or less vs. 5-10% for better income) did not eat breakfast every day. Not eating breakfast every day nearly doubled the odds (odds ratio=1.9, 95% confidence interval 1.2-3.2) of being overweight at 4.5 years when mother's immigrant status, household income and number of overweight/obese parents were part of the analysis. CONCLUSION: Although our results require replication before public policy changes can be advocated, encouraging breakfast consumption among pre-school children is probably warranted and targeting families of low socio-economic status could potentially help in the prevention of childhood obesity.     

Vertical stratification and trophic interactions among organisms of a soil decomposer food web – a field experiment using 15N as a tool

In this field study, we explored the spatial segregation between the litter- and humus-inhabiting organisms of the detrital food web using ¹⁵N-isotope technique. The study was established in 11 × 11 m plots fertilized with ¹⁵N-labelled urea. Ten years after urea application, soil samples were taken, both from the litter layer and the combined F+H layer. The samples were analysed for N content and the proportion of ¹⁵N in (i) the residual organic matter in the litter and F+H layer (excluding microbes), (ii) microbial biomass, and (iii) various feeding guilds of soil fauna. The basal resource, soil microbes, and the fauna were more enriched with ¹⁵N in the F+H layer than in the litter layer. In the litter layer, the ¹⁵N enrichment of the expected food source equalled the one of the consumers, whereas in the F+H layer all trophic groups, except microbes and small microbi-detritivores, showed a significantly lower ¹⁵N enrichment than their expected food source. The results indicate that large and mobile humus-inhabiting decomposers exploit the overlying litter layer as a feeding site, whereas the feeding of the more sedentary smaller organisms is restricted to the humus layer.     

波密县近30 a气候变化特征

根据西藏自治区林芝地区波密县气象局1981年1月-2010年12月的气温及降水资料,分析了波密县近30 a来的气候变化特征,得出近30 a来波密县降水量呈下降趋势,夏、秋季降水量减少较为明显,冬季降水量却呈上升趋势;年平均气温呈上升趋势,四季气温也呈上升趋势,尤其是冬季变暖最为明显;年极端最低气温的上升趋势远远大于极端高温的上升趋势。     

德州市近50 a来旱涝特征分析

对德州市1951-1999年的逐年降水数据、区域旱涝灾害成灾面积及降水与成灾之间的相关性进行统计分析.依据Z指标划分7个旱涝等级,给出旱涝指标与旱涝成灾面积的多年变化趋势以及它们之间的相关系数.结果表明:德州市近50 a来,降水变化呈下降趋势;1975年以前偏涝,间或有旱的年份出现,极涝年份为1953年、1961年、1964年;1975年以后偏旱,间或有涝的年份出现,极旱年份为1981年;旱灾面积越来越大,涝灾面积越来越少,20世纪60-70年代为旱涝灾害成灾面积变化的转折点.降水指标为该市今后旱涝预测提供了可能的途径.     

Testing a key assumption of wildlife buffer zones: is flight initiation distance a species-specific trait?

The distance at which animals flee an approaching predator is known as the ‘flight initiation distance’ (FID). Wildlife managers use FID to develop buffer zones to reduce human impacts on wildlife. Many variables have been demonstrated to influence FID leading one to question whether it can be viewed as a species-specific trait. We tested this critical assumption for developing buffer zones by experimentally approaching eight species of shorebirds found at six sites around Botany Bay, 15 km south of Sydney, Australia. Botany Bay encompasses a range of human impacted areas, from urban developments with high levels of human presence, through to National Parks and wildlife protection areas where human presence is significantly lower. We found that both species and site influenced the distance birds flew away from an approaching human. Importantly, however, there was no significant statistical interaction between site and species demonstrating that ‘flighty’ species were consistently flighty while more tolerant species were consistently tolerant. Taken together, these results suggest that FID can therefore be viewed as a species-specific trait for these shorebirds. The great variability in FID suggests that wildlife managers should be somewhat conservative in developing buffer zones, but they can use previously published FID data for a given species as guidelines for setting buffer zones.     

Nitrate removal from ground water — use of a nitrate selective resin and a low concentrated regenerant

A new, strong base, macro-porous anion exchange resin, Amberlite IRA 996, appeared to be more nitrate selective than sulfate selective in treating high nitrate concentrations (18 mg NO _inf3 ^sup? -N L^?1) in potable water. When regeneration is carried out in a closed circuit in which a biological denitrification reactor is incorporated to remove nitrate from the regenerant, regeneration salt requirement and brine production can be minimized. In this combination of ion exchange and biological denitrification, regeneration with 30 g NaHCO₃ L^?1) is possible in 6 hr at a flow rate of 11 BV hr^?1. Accumulation of sulfate in the closed regeneration circuit does not affect the nitrate capacity of the resin.