Growth, photosynthetic and respiratory responses to sub-lethal copper concentrations in Scenedesmus incrassatulus (Chlorophyceae)

In the present paper we investigated the effects of sub-lethal concentrations of Cu²⁺ in the growth and metabolism of Scenedesmus incrassatulus. We found that the effect of Cu²⁺ on growth, photosynthetic pigments (chlorophylls and carotenoids) and metabolism do not follow the same pattern. Photosynthesis was more sensitive than respiration. The analysis of chlorophyll a fluorescence transient shows that the effect of sub-lethal Cu²⁺ concentration in vivo, causes a reduction of the active PSII reaction centers and the primary charge separation, decreasing the quantum yield of PSII, the electron transport rate and the photosynthetic O₂ evolution. The order of sensitivity found was: Growth > photosynthetic pigments content = photosynthetic O₂ evolution > photosynthetic electron transport > respiration. The uncoupled relationship between growth and metabolism is discussed.     

The presence of vanadium in groundwater of southeastern extreme the pampean region Argentina Relationship with other chemical elements

Changes in the quality of groundwater resources are related to the presence and concentration of contaminants, especially trace elements such as arsenic, boron, fluoride and vanadium. Vanadium is a rare element naturally abundant, generally found in combination with other elements. Vanadium pentoxide is known to have aneugenic effects. Thus, a study was carried out to assess the presence of vanadium in the groundwater of the southeastern pampean region of Argentina, which constitutes the main water supply for the local population. Statistical and correlational analyses were applied to identify possible interrelationships between vanadium and another chemical elements. Vanadium was found in all groundwater samples. The minimum and maximum vanadium concentrations found were 0.05 mg/l and 2.47 mg/l, respectively. Vanadium is significantly correlated with other trace elements such as arsenic, fluoride and boron. The interrelationship between vanadium and the presence of volcanic glass in sediments is not significant as expected.     

Using GIS to Delineate Headwater Stream Origins in the Appalachian Coalfields of Kentucky

Headwater streams have a significant nexus or physical, chemical, and/or biological connection to downstream reaches. Generally, defined as 1st‐3rd order with ephemeral, intermittent, or perennial flow regimes, these streams account for a substantial portion of the total stream network particularly in mountainous terrain. Due to their often remote locations, small size, and large numbers, conducting field inventories of headwater streams is challenging. A means of estimating headwater stream location and extent according to flow regime type using publicly available spatial data is needed to simplify this complex process. Using field‐collected headwater point of origin data from three control watersheds, streams were characterized according to a set of spatial parameters related to topography, geology, and soils. These parameters were (1) compared to field‐collected point of origin data listed in three nearby Jurisdictional Determinations, (2) used to develop a geographic information system (GIS)‐based stream network for identifying ephemeral, intermittent, and perennial streams, and (3) applied to a larger watershed and compared to values obtained using the high‐resolution National Hydrography Dataset (NHD). The parameters drainage area and local valley slope were the most reliable predictors of flow regime type. Results showed the high‐resolution NHD identified no ephemeral streams and 9 and 65% fewer intermittent and perennial streams, respectively, than the GIS model.     

Platinum (IV) recovery from chloride solution by functionalized acrylic copolymers

Two acrylic adsorbents with different morphological structures and bearing amidoethylenamine and thiol groups were obtained and used for platinum sorption from chloride solution by the batch method. Physico-chemical parameters that influence adsorption such as initial Pt(IV) concentration, stirring time, pH, and adsorbent amount were investigated. The thermodynamic parameters of Pt(IV) sorption on the synthesized adsorbent were also evaluated based on Langmuir and Freundlich isotherms. Thermodynamic parameters estimated from Langmuir constants indicated that the adsorption is spontaneous, exothermic and there is a disordered state at the molecular level. The models used to analyze the sorption rate led to the conclusion that the most important step in the sorption of Pt(IV) could be both particle diffusion and chemical reaction of [PtCl₆]⁻ with amine functional groups. Thus, both the ion exchange and complex formation mechanisms can occur via nitrogen atoms in the recovery of Pt(IV) on the studied adsorbent.     

The Influence of Knowledge and Motivation on Sustainable Label Use

Sustainable labels are considered the best way for consumers to identify brands with environmental or social attributes on the shelves, and therefore promoted as a means to develop the so-called “ethical markets”. However, little is known about how consumers use these brands. This paper tries to offer complementary theoretical insights on the determinants of sustainable label use by drawing on the economic model of information search; in particular, it examines the influence of two factors on the purchase of such labels: motivation and knowledge. Information was gathered through a structured questionnaire in personal interviews with 289 primary buyers. The study found that education influences directly knowledge, while Motivation influences Label use both directly and indirectly, via Label knowledge. This study concludes that Motivation is the most powerful factor to explain Label use; knowledge is a necessary but not sufficient condition. Even more, consumers may not have a good understanding of sustainable labels and still use them in their purchasing decisions. This suggests that there is a dual processing mode of sustainable labels, both systematic and heuristic.     

Global Urban Growth and the Geography of Water Availability,Quality, and Delivery

Globally, urban growth will add 1.5 billion people to cities by 2030, making the difficult task of urban water provisions even more challenging. In this article, we develop a conceptual framework of urban water provision as composed of three axes: water availability, water quality, and water delivery. For each axis, we calculate quantitative proxy measures for all cities with more than 50,000 residents, and then briefly discuss the strategies cities are using in response if they are deficient on one of the axes. We show that 523 million people are in cities where water availability may be an issue, 890 million people are in cities where water quality may be an issue, and 1.3 billion people are in cities where water delivery may be an issue. Tapping into groundwater is a widespread response, regardless of the management challenge, with many cities unsustainably using this resource. The strategies used by cities deficient on the water delivery axis are different than for cities deficient on the water quantity or water quality axis, as lack of financial resources pushes cities toward a different and potentially less effective set of strategies.     

Improving the sampling strategy of the Joint Danube Survey 3 (2013) by means of multivariate statistical techniques applied on selected physico-chemical and biological data

The concept of basin-wide Joint Danube Survey (JDS) was launched by the International Commission for the Protection of the Danube River (ICPDR) as a tool for investigative monitoring under the Water Framework Directive (WFD), with a frequency of 6 years. The first JDS was carried out in 2001 and its success in providing key information for characterisation of the Danube River Basin District as required by WFD lead to the organisation of the second JDS in 2007, which was the world’s biggest river research expedition in that year. The present paper presents an approach for improving the survey strategy for the next planned survey JDS3 (2013) by means of several multivariate statistical techniques. In order to design the optimum structure in terms of parameters and sampling sites, principal component analysis (PCA), factor analysis (FA) and cluster analysis were applied on JDS2 data for 13 selected physico-chemical and one biological element measured in 78 sampling sites located on the main course of the Danube. Results from PCA/FA showed that most of the dataset variance (above 75 %) was explained by five varifactors loaded with 8 out of 14 variables: physical (transparency and total suspended solids), relevant nutrients (N–nitrates and P–orthophosphates), feedback effects of primary production (pH, alkalinity and dissolved oxygen) and algal biomass. Taking into account the representation of the factor scores given by FA versus sampling sites and the major groups generated by the clustering procedure, the spatial network of the next survey could be carefully tailored, leading to a decreasing of sampling sites by more than 30 %. The approach of target oriented sampling strategy based on the selected multivariate statistics can provide a strong reduction in dimensionality of the original data and corresponding costs as well, without any loss of information.     

Trisomy 2 due to a 3:1 segregation in an abortion studied by QF-PCR and CGH

Balanced reciprocal translocation is one of the known causes of recurrent spontaneous abortions. Cytogenetic studies of unbalanced miscarriages are difficult due to the growth failure of early loss and usually macerated abortions. We present a molecular study of an abortion in which the father carries a balanced reciprocal translocation t(2;17)(q32.1;q24.3) using QF-PCR and CGH techniques. DNA analysis showed the presence of a trisomy 2 due to a 3:1 interchange segregation. Recombinant events could also be investigated by comparing DNA samples from the family. We propose QF-PCR in addition to CGH as an efficient diagnostic method to improve our knowledge of unbalanced offspring in balanced translocation carriers. Copyright © 2005 John Wiley & Sons, Ltd.     

Organochlorine contaminants in hair of adolescents from Iassy, Romania

Human hair samples (n=42) from Iassy county (Eastern Romania) collected in 2002-2003 from adolescents were analyzed for hexachlorocyclohexane (HCH) isomers, p,p'-DDT and its metabolites, hexachlorobenzene (HCB), chlordane and metabolites and 5 polychlorinated biphenyl (PCB) congeners. Very low levels were found for HCB and oxychlordane (0.8 and 2.5 ng g(-1)) indicating a low usage of these pesticide formulations in the studied area. In case of HCHs, gamma-HCH isomer was measured at higher median concentrations (79 ng g(-1) hair) compared to the beta-HCH isomer (55 ng g(-1)), which generally is the most prevalent from HCHs. The DDTs profile consisted in p,p'-DDE and p,p'-DDT which levels correspond to 81% of sum DDTs. Very high median concentrations measured for p,p'-DDT (192 ng g(-1)) combined with lower values for p,p'-DDE/p,p'-DDT of 0.4 (from 0.20 to 2.0) in all hair samples suggest recent exposure to "fresh" DDT. When gender was considered, significantly higher concentrations for most of the investigated contaminants were found in girls hair compared to boys. Very high levels were found in the present study for HCHs and DDTs compared to samples from Greece, Western Europe and China. In case of PCBs, the levels found in Romanian samples were found to be in the same range compared to other previously published data.