First recorded proliferation of Coolia monotis (Meunier, 1919) in the North Lake of Tunis (Tunisia) correlation with environmental factors

Coolia monotis is a potentially toxic epiphytic dinoflagellate widespread along the Mediterranean coasts, where it is frequently detected year round at low concentrations. However, it only proliferates recurrently in some localities. The North Lake of Tunis is one of the affected areas in the southwestern part of the Mediterranean Sea. This site is one of the most productive aquatic Tunisian areas (Recreational Fisheries and shellfish collecting). In the south part of this area of study, recurrent C. monotis proliferation (5 ×10⁵ cells per liter) took place in late spring and early summer of 2006. During this proliferation, the spatial distribution of C. monotis species, phytoplankton community, and abiotic factors were studied. The composition of the phytoplankton community exhibited a clear dominance of dinoflagellates over other genera. We suggest that proliferation development of C. monotis was linked to climatic conditions, water temperature (r?=?0.24, p?<?0.05) and high concentrations of nitrogenous nutrients, essentially NH₄ ^?+? (r?=?0.18, p?<?0.05) and NO₃ ^??? (r?=?0.21, p?<?0.05).     

San copolymer membranes with ion exchangers for Cu(II) removal from synthetic wastewater by electrodialysis

Heterogeneous membranes were obtained by using styrene-acrylonitrile copolymer (SAN) blends with low content of ion-exchanger particles (5 wt.%). The membranes obtained by phase inversion were used for the removal of copper ions from synthetic wastewater solutions by electrodialytic separation. The electrodialysis was conducted in a three cell unit, without electrolyte recirculation. The process, under potentiostatic or galvanostatic control, was followed by pH and conductivity measurements in the solution. The electrodialytic performance, evaluated in terms of extraction removal degree (rd) of copper ions, was better under potentiostatic control then by the galvanostatic one and the highest (over 70%) was attained at 8 V. The membrane efficiency at small ion-exchanger load was explained by the migration of resin particles toward the pores surface during the phase inversion. The prepared membranes were characterized by various techniques i.e. optical microscopy, Fourier transform infrared spectroscopy, scanning electron microscopy, thermogravimetric analysis and differential thermal analysis and contact angle measurements.     

Prenatally detected trisomy 7 mosaicism in a dysmorphic child

Trisomy 7 mosaicism was detected prenatally in cultured amniocytes but not in fetal lymphocytes. The child that was born had pigmentary changes of the skin and facial asymmetry suggestive of a chromosomal mosaicism. Skin fibroblasts were studied and trisomy 7 mosaicism was confirmed. At 3 years of age the boy had developed mentally within normal limits. However, dysmorphic findings include sparse hair, short leftpalpebral fissure, ptosis of the left eyelid, strabismus, enamel dysplasia, low-set and posteriorly rotated ears and undescended testes. These findings share some common features with previously reported cases of trisomy 7 mosaicism. Copyright © 2002 John Wiley & Sons, Ltd.     

Seasonal dynamic and in situ division rates of the dominant Dinophysis species in Punic harbors of Carthage (Gulf of Tunis, South Mediterranean)

This study investigates spatio-temporal variations of in situ division rate (μ) of two species of the genus Dinophysis. Based on a postmitotic index approach, estimates of μ from net-haul samples were compared during five daily cell cycles studies in three stations of the Punic harbors of Carthage (Gulf of Tunis). To study the annual cycle of Dinophysis spp., weekly sampling were carried out from March 2008 to June 2010. In addition, sampling over 24 h was conducted on three-cycle studies in late spring and two-cycle studies in autumn, seasons characterized by Dinophysis proliferations. We recorded important abundances of Dinophysis sacculus stein (2.25?×?10⁴ cells/l, June 2008) and Dinophysis cf. acuminata (3?×?10⁴ cells/l, June 2009). Cellular division was phased in D. sacculus stein and D. cf. acuminata, but the division time, required for the population cohorts to pass from one phase to another, and values of estimated division rates varied between seasons and stations for the same species. D. cf. acuminata exhibit moderate (0.22 day^?1) to high (0.68 day^?1) value of μ. In contrast, D. sacculus shows very low μ values (0.02–0.17 day^?1) in autumn season to moderate values (0.21–0.35 day^?1) in late spring. The results presented here confirm that the postmitotic index approach allowed estimated of μ at low field depths and concentrations (10²–10³ cells/l).     

Spatial water quality assessment of Langat River Basin (Malaysia) using environmetric techniques

This study investigates the spatial water quality pattern of seven stations located along the main Langat River. Environmetric methods, namely, the hierarchical agglomerative cluster analysis (HACA), the discriminant analysis (DA), the principal component analysis (PCA), and the factor analysis (FA), were used to study the spatial variations of the most significant water quality variables and to determine the origin of pollution sources. Twenty-three water quality parameters were initially selected and analyzed. Three spatial clusters were formed based on HACA. These clusters are designated as downstream of Langat river, middle stream of Langat river, and upstream of Langat River regions. Forward and backward stepwise DA managed to discriminate six and seven water quality variables, respectively, from the original 23 variables. PCA and FA (varimax functionality) were used to investigate the origin of each water quality variable due to land use activities based on the three clustered regions. Seven principal components (PCs) were obtained with 81% total variation for the high-pollution source (HPS) region, while six PCs with 71% and 79% total variances were obtained for the moderate-pollution source (MPS) and low-pollution source (LPS) regions, respectively. The pollution sources for the HPS and MPS are of anthropogenic sources (industrial, municipal waste, and agricultural runoff). For the LPS region, the domestic and agricultural runoffs are the main sources of pollution. From this study, we can conclude that the application of environmetric methods can reveal meaningful information on the spatial variability of a large and complex river water quality data.     

Biomonitoring of several toxic metal(loid)s in different biological matrices from environmentally and occupationally exposed populations from Panasqueira mine area,Portugal

In the Panasqueira mine area of central Portugal, some environmental media show higher metal(loid) concentrations when compared with the local geochemical background and the values proposed in the literature for these environmental media. In order to evaluate the effect of the external contamination on selected indexes of internal dose, As, Cd, Cu, Cr, Fe, Hg, Mg, Mn, Mo, Ni, Pb, S, Se, Si, and Zn were quantified by inductively coupled plasma mass spectrometry and inductively coupled plasma optical emission spectrometry in blood, urine, hair and nail samples from individuals environmentally (N = 41) and occupationally exposed (N = 41). A matched control group (N = 40) was also studied, and data from the three groups were compared. Results obtained agreed with those reported by environmental studies performed in this area, pointing to populations living nearby and working in the mine being exposed to metal(loid)s originated from mining activities. Arsenic was the element with the highest increase in exposed populations. The concentration of other elements such as Cr, Mg, Mn, Mo, Ni, Pb, S, Se, and Zn was also increased, although at a lesser extent, specifically in the individuals environmentally exposed and in females. These findings confirm the need for competent authorities to act as soon as possible in this area and implement strategies aimed to protect exposed populations and the entire ecosystem.     

Occurrence of diarrhetic shellfish poisoning (DSP) toxins in clams (Ruditapes decussatus) from Tunis north lagoon

The main diarrhetic shellfish toxins, okadaic acid (OA) and dinophysistoxin-1, 2 (DTX-2, 2) were detected by liquid chromatography-tandem mass spectrometry (LC-MS/MS) as pyrenacyl esters in clams (Ruditapes decussatus) collected in Tunis north lagoon from January 2007 to June 2008. Sample analyses by LC-MS/MS displayed OA and related congeners (DTX-2, 2) with a highest detected level of 21 μg OA eq/kg shellfish meat for the samples of January 2007. Nevertheless, all samples were MBA negative. During the study period, potentially toxic dinoflagellate Dinophysis sacculus was recorded all year, blooming at different times. Highest concentrations were recorded during January 2007 with 4.6?×?10(4) cells per liter and 4.10(4) cells per liter in the northern and southern districts, respectively. Results show that there is no significant correlation between D. sacculus densities in water column and diarrhetic shellfish poisoning (DSP) toxins concentrations unregistered in clams. These data reveal that DSP toxicity in clams of Tunis north lagoon is low according to European regulatory limit (160 μg OA eq/kg shellfish meat). However, a potential threat, in this area, is represented by DSP toxic species as D. sacculus and provides grounds for widen and reinforcing sanitary control of the phycotoxin measures in the region.     

From “What is” to “What Should Become” Conservation Biology? Reflections on the Discipline’s Ethical Fundaments

In this essay, I build on the article by Soulé that established the foundation for the field of conservation biology. I analyze the presuppositions that have guided the discipline’s ethics in the 30 years since that article first appeared. I argue that conservation biology’s normative postulates introduced a paradigm shift that placed the diversity of the biota instead of the biota itself at the center of its ethics. I show that the ensuing priorities in the valuation of nature entail several contradictions at the ethical level and are justifiable only through scientific postulates. Identifying potential revisions and latent ideological issues in science, I defend the position that such scientific legitimization of conservation measures becomes disputable when this option undermines the ethical status of non-human life. Furthermore, I explain the absence of social feedback regarding conservation measures from the perspective of this shift. I conclude with an invitation to critically rethink the ethical basis of conservation sciences so that these fields may achieve their intention of playing a key role in halting the destruction of nature and in encouraging society’s support.     

Local community acceptance of the rare earth industry: the case of the Lynas Advanced Materials Plant (LAMP) in Malaysia

This paper provides a detailed analysis of the local community response to a newly installed rare earth (RE) refinery facility and the factors underlying its acceptance. House-to-house interviews, using structured questionnaire, were conducted in 2013 (N = 370). Results show that the community was divided into deciding whether they agreed with the presence of the facility, 41.36 % (for) and 41.62 % (against). The remaining fraction of the community was undecided, which made up 17.03 % of the total respondents. This paper identifies six significant predictors of risk acceptance: gender, education status, place of residence, Factor 1 (variables—perception of safety, concern on effects, and trust in the operators), Factor 2 (variables—social and individual benefits), and Factor 3 (variables—no confidence in government). This study gives insights on how the public respond to potential hazardous facilities and highlights the need for policy makers to consider public sentiment which can interfere with further expansion of the RE industry.