The aim of this study was to conduct a POP biomonitoring programme for children in high-risk areas. We evaluated 247 serum samples from children between the ages of 6 and 12years old from two zones ...in Mexico: (1) indigenous zones, which included Cuatlamayan (CUA), Tocoy (TOC), and Santa Maria Picula (SAM); and (2) industrial zones, which included Tercera Chica (TC), Industrial San Luis (IND) and Rincon de San Jose (SJR); Mundo Nuevo (MN); and Alpuyeca (ALP). Our results showed that α-endosulfan was similar to CUA, TOC, SAM, TC and MN (178.6–306.9ng/g lipid). β-Endosulfan levels were higher in ALP (901.5ng/g lipid), followed by CUA (139.9ng/g lipid) and TOC, SAM, TC and MN, which had similar levels (55.4–64.5ng/g lipid). For endosulfan sulfate, the ALP community had the highest concentration levels (1096.4ng/g lipid), whereas CUA and TOC (212.3 and 289ng/g lipid, respectively) had concentrations similar to those found in SAM and TC (99.5 and 119.1ng/g lipid, respectively). DDE levels were found in malaria-endemic areas of SAM, CUA and TOC (1782.2, 1358.3 and 57.0ng/g lipid), followed by MN (35.1ng/g lipid). HCB concentration levels were found to be higher in MN and SJR (691.8 and 575.4ng/g lipid, respectively), followed by CUA and TC (363.9 and 269.1ng/g lipid, respectively), with levels similar to those found in TOC and SAM (191.8 and 181.9ng/g lipid, respectively). Finally, PCB 101 concentration levels were found to be the highest in ALP (1032.7ng/g lipid), followed by similar levels of SJR and IND (567.5 and 327.3ng/g lipid, respectively) and TC and MN, with 109.1 and 144.5ng/g lipid, respectively. The evidence provided by this exploratory study indicates that the evaluation of the health risks posed to children living in contaminated areas is a high priority health issue.
Types of potentially contaminated sites: indigenous area: 1-Cuatlamayan (CUA), SLP; 2-Tocoy (TOC), S.L.P.; 3-Santa Maria Picula (SMP), S.L.P.; bricked area: 4-Tercera chica, S.L.P (TC); industrial area 5-Industrial San Luis, S.L.P (IND).; Hazardous waste landfills 6-Rincon de San Jose, SLP (SJR); petrochemical area: 7-Mundo Nuevo, Coatzacoalcos, Ver (MN).; agricultural industrial area: 8-Alpuyeca, Morelos (ALP). Display omitted
•Endosulfan, DDE, HCB and PCB 101 was detected in over 55% of the child population•Children living in contaminated sites showed high levels of POPs in serum•Our results can be used as a baseline for future research of biomonitoring
► Role of Fe-oxide/hydroxide rich sediments of tropical reservoirs on P sequestration. ► P adsorption capacity of sediments is predominantly associated with Fe. ► Clay fraction mineralogy dominated ...by oxides/hydroxides-Fe and kaolinite. ► Strong retention of phosphate ions through surface adsorption/precipitation phenomena. ► Study of mineralogy/chemistry of sediments could predict P levels in surface waters.
This study investigates the important role of Fe-oxide/hydroxide-rich bottom sediments, from two Brazilian tropical reservoirs, on P sequestration from the overlying waters, which decreases the risk of eutrophication. Data on P fractionation indicates that P adsorption capacity of sediments is predominantly associated with Fe, followed by orthosphosphate adsorbed onto Al hydr(oxides) and onto different forms of apatite (Ca–P). The soluble and loosely bound P-forms are low. To have a better understanding of the role of Fe oxides on the adsorption and sequestration of P in the reservoirs, data obtained by sequential extraction of P have been related to concentrations of total Fe and of various Fe-fractions extracted through an optimized fractionation scheme. These analyses indicated high levels of Fe bound to oxides/hydroxides. These mineral oxides, and the preponderance of pH-dependent charged clay minerals (kaolinite) in the clay fraction, induce the sequestration of the P entering the lakes, mainly in particulate form, by strong retention of
PO
4
3
-
through surface adsorption and precipitation phenomena. Phosphorus-retention provided by the replacement of OH
− groups on the basal plane of the minerals, for P anions, decreases the negative impact of P inputs in these water systems. There is significant correlation between the concentrations of soluble reactive P in the water (SRP) and major chemical components of sediments (SiO
2, Fe
2O
3, Al
2O
3, K
2O, P
2O
5), which are related to the dominant bedrock geology. The interaction of SRP with bed-sediments and the chemical conditions of the environment (decrease of redox potential with depth and, in the dry period, a low O
2 abundance), can explain fluctuations of SRP and TP (total P) in the water column. Due to the dynamic equilibrium in the sediment–water interface, in the dry season, reducing conditions in hypoliminia enhance the reduction of Fe(III) to the more soluble Fe(II) with subsequent release of the strongly retained P. This mechanism increases the soluble P fraction in sediments and the soluble reactive P in the water column, in this period. The straight linkage between geochemical properties of sediments and P concentration in the water column reported in this article suggests that study of the mineralogical and geochemical composition of bottom sediments could help to improve model predictions of P concentrations in surface waters.
The aim of the present work was to complete an exposure assessment in three Mexican indigenous communities using the community-based health risk assessment, which is the first step in the CHILD ...framework. We used 1-hydroxypyrene (1-OHP) as an exposure biomarker to polycyclic aromatic hydrocarbons (PAHs) and
trans
,
trans
-muconic acid (
t
,
t
-MA) as an exposure biomarker to benzene, persistent organic pollutants (POPs), lead, manganese, arsenic, and fluoride. Anthropometric measurements were also taken. In these communities, high percentages of children with chronic malnutrition were found (28 to 49 %) based on their weight and age. All communities showed a high percentage of children with detectable levels of four or more compounds (70 to 82 %). Additionally, our results showed that in indigenous communities, children are exposed to elevated levels of certain environmental pollutants, including manganese with 17.6, 16.8, and 7.3 μg/L from SMP, TOC, and CUA, respectively. Lead and HCB levels were similar in the indigenous communities (2.5, 3.1, and 4.2 μg/dL and 2.5, 3.1, and 3.7 ng/mL, respectively). 1-OHP and
t
,
t
-MA levels were higher in TOC (0.8 μmol/mol of creatinine, 476 μg/g of creatinine, respectively) when compared with SMP (0.1 μmol/mol of creatinine, 215.5 μg/g of creatinine, respectively) and CUA (0.1 μmol/mol of creatinine, 185.2 μg/g of creatinine, respectively). DDE levels were 30.7, 26.9, and 9.6 ng/mL in CUA, SMP, and TOC, respectively. The strength of this study is that it assesses exposure to pollutants with indications for the resultant risk before an intervention is made by the CHILD program to manage this risk in the indigenous communities. Considering the large number of people, especially children, exposed to multiple pollutants, it is important to design effective intervention programs that reduce exposure and the resultant risk in the numerous indigenous communities in Mexico.
It has been described that the frequency ranges at which theta, mu and alpha rhythms oscillate is increasing with age. The present report, by analyzing the spontaneous EEG, tries to demonstrate ...whether there is an increase with age in the frequency at which the cortical structures oscillate. A topographical approach was followed. The spontaneous EEG of one hundredand seventy subjects was recorded. The spectral power (from 0.5 to 45.5 Hz) was obtained by means of the Fast Fourier Transform. Correlations of spatial topographies among the different age groups showed that older groups presented the same topographical maps as younger groups, but oscillating at higher frequencies. The results suggest that the same brain areas oscillate at lower frequencies in children than in older groups, for a broad frequency range. This shift to a higher frequency with age would be a trend in spontaneous brain rhythm development.
Tourmalinization associated with peraluminous granitic intrusions in metapelitic host-rocks has been widely recorded in the Iberian Peninsula, given the importance of tourmaline as a tracer of ...granite magma evolution and potential indicator of Sn-W mineralizations. In the Penamacor-Monsanto granite pluton (Central Eastern Portugal, Central Iberian Zone), tourmaline occurs: (1) as accessory phase in two-mica granitic rocks, muscovite-granites and aplites, (2) in quartz (±mica)-tourmaline rocks (tourmalinites) in several exocontact locations, and (3) as a rare detrital phase in contact zone hornfels and metapelitic host-rocks. Electron microprobe and stable isotope (δ
18
O, δD, δ
11
B) data provide clear distinctions between tourmaline populations from these different settings: (a) schorl–oxyschorl tourmalines from granitic rocks have variable foititic component (
X
□ = 17–57 %) and Mg/(Mg + Fe) ratios (0.19–0.50 in two-mica granitic rocks, and 0.05–0.19 in the more differentiated muscovite-granite and aplites); granitic tourmalines have constant δ
18
O values (12.1 ± 0.1 ‰), with wider-ranging δD (−78.2 ± 4.7 ‰) and δ
11
B (−10.7 to −9.0 ‰) values; (b) vein/breccia oxyschorl Mg/(Mg + Fe) = 0.31–0.44 results from late, B- and Fe-enriched magma-derived fluids and is characterized by δ
18
O = 12.4 ‰, δD = −29.5 ‰, and δ
11
B = −9.3 ‰, while replacement tourmalines have more dravitic compositions Mg/(Mg + Fe) = 0.26–0.64, close to that of detrital tourmaline in the surrounding metapelitic rocks, and yield relatively constant δ
18
O values (13.1–13.3 ‰), though wider-ranging δD (−58.5 to −36.5 ‰) and δ
11
B (−10.2 to −8.8 ‰) values; and (c) detrital tourmaline in contact rocks and regional host metasediments is mainly dravite Mg/(Mg + Fe) = 0.35–0.78 and oxydravite Mg/(Mg + Fe) = 0.51–0.58, respectively. Boron contents of the granitic rocks are low (<650 ppm) compared to the minimum B contents normally required for tourmaline saturation in granitic melts, implying loss of B and other volatiles to the surrounding host-rocks during the late-magmatic stages. This process was responsible for tourmalinization at the exocontact of the Penamacor-Monsanto pluton, either as direct tourmaline precipitation in cavities and fractures crossing the pluton margin (vein/breccia tourmalinites), or as replacement of mafic minerals (chlorite or biotite) in the host-rocks (replacement tourmalinites) along the exocontact of the granite. Thermometry based on
18
O equilibrium fractionation between tourmaline and fluid indicates that a late, B-enriched magmatic aqueous fluid (av. δ
18
O ~12.1 ‰, at ~600 °C) precipitated the vein/breccia tourmaline (δ
18
O ~12.4 ‰) at ~500–550 °C, and later interacted with the cooler surrounding host-rocks to produce tourmaline at lower temperatures (400–450 °C), and an average δ
18
O ~13.2 ‰, closer to the values for the host-rock. Although B-metasomatism associated with some granitic plutons in the Iberian Peninsula seems to be relatively confined in space, extending integrated studies such as this to a larger number of granitic plutons may afford us a better understanding of Variscan magmatism and related mineralizations.
Since 1997, fledgling Scops owls (Chordata: Strigidae) have been brought to the Brinzal Owl Rescue Centre (Madrid, Spain) with severe lesions in their oral cavities. Lesions consist of the presence ...of proliferative necrotic material in the oral cavity resulting in white plaques, which can lead to death by starvation. This disease has been detected in owls only within the limits of the city of Madrid. The etiologic agent has been identified as Gongylonema sp. (Nematoda: Spirurida), a nematode genus that includes a coprophagous arthropod as intermediate host in its cycle. The aim of this study was to identify the intermediate host of the parasite. Our work was structured in four component phases: i) Diet study of newborn chicks; ii) trapping arthropods that could be intermediate hosts; iii) molecular detection of the parasite in the selected arthropods: and iv) molecular characterization of the detected parasites by amplifying the cox1 gene. Four male owls were radio-tagged in order to locate their nests and a camera trap was placed to identify the prey brought to the owlets. Secondly, the arthropods present in the hunting areas of the owls were sampled, identified and analyzed by real time PCR (rtPCR). Only oriental cockroaches, B. orientalis (Arthropoda: Blattodea), were positive by rtPCR detection of Gongylonema sp. (66.7%). The nematodes obtained from cockroaches had a 99.8% identity of the cox1 gene with the Gongylonema sp. isolated for the first time in a Scops owl. Furthermore, these sequences only showed an <89% identity with all the other Gongylonema sequences available in the GenBank database. We conclude that the oriental cockroach should be considered as an intermediate host of the etiologic agent of NOD.
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•Cockroaches (Blata orientalis) are the most available prey for the scops owls in the green areas of Madrid City.•Blata orientalis was the only sampled invertebrate positive to Gongylonema sp. in the PCR analyses.•Blata orientalis and should be considered as the most likely intermediate host of Gongylonema sp. for the scops owl in the city of Madrid.
Knowledge on hard coatings has been applied in the energy field extending their use as protecting coatings of steam power generation plants components. The role of the layer architecture of Cr–Ti–N ...based coatings deposited by reactive cathodic arc evaporation on P92 steel substrates was studied with the focus on their oxidation resistance at 650 °C in 100% steam atmosphere up to 2000 h. Characterization of the coatings was performed by gravimetry, scanning electron microscopy, electron probe microanalysis, glow discharge optical emission spectroscopy, X-ray diffraction, thermodynamic simulations using the CALPHAD method, Rockwell C indentation and nanoindentation. The layered arrangement improves the oxidation resistance of TiN under the working conditions of steam power plants, as well as the mechanical properties of CrN. The produced architectures performance under the described working conditions boosts the understanding of the processes taking place at high temperature, making possible the design of optimal coatings combining the best behavior of both nitrides for each specific application, reaching a corrosion protection at high temperature in water vapor comparable to that of CrN and a hardness and Young's modulus as high as those of TiN.
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•Sand fly blood feeding resources in southwest Spain.•Leishmania DNA in Sergentomyia minuta and Phlebotomus perniciosus.•Risk factors associated to Phlebotomus perniciosus and ...Sergentomyia minuta densities.•Entomological aspects and seasonal distribution of sand flies species in Extremadura, Spain.
Leishmaniosis caused by Leishmania infantum is present in Mediterranean countries, with high prevalence in areas of the center and south of Spain. However, in some regions such as Extremadura (in southwest of Spain), data has not been updated since 1997. The aim of this work was (i) to provide information about the distribution of phlebotomine sand fly species in western of Spain (Extremadura region), (ii) to determine risk factors for the presence of sand fly vectors and (iii) to detect Leishmania DNA and identify blood meal sources in wild caught females.
During 2012–2013, sand flies were surveyed using CDC miniature light-traps in 13 of 20 counties in Extremadura. Specimens were identified morphologically and females were used for molecular detection of Leishmania DNA by kDNA, ITS-1 and cyt-B. In addition, blood meals origins were analyzed by a PCR based in vertebrate cyt b gene.
A total of 1083 sand flies of both gender were captured and identified. Five species were collected, Phlebotomus perniciosus (60.76%), Sergentomyia minuta (29.92%), P. ariasi (7.11%), P. papatasi (1.48%) and P. sergenti (0.74%). The last three species constitute the first report in Badajoz, the most southern province of Extremadura region. Leishmania DNA was detected in three out of 435 females (one P. pernicious and two S. minuta). Characterization of obtained DNA sequences by phylogenetic analyses revealed close relatedness with Leishmania tarentolae in S. minuta and L. infantum in P. perniciosus. Haematic preferences showed a wide range of hosts, namely: swine, humans, sheep, rabbits, horses, donkeys and turkeys.
The simultaneous presence of P. perniciosus and P. ariasi vectors, the analysis of blood meals, together with the detection of L. infantum and in S. minuta of L. tarentolae, confirms the ideal conditions for the transmission of this parasitosis in the western of Spain. These results improve the epidemiological knowledge of leishmaniosis and its vectors in this part of Spain, highlighting the need for ongoing entomological and parasitological surveillance.
By means of angle-resolved photoemission spectroscopy (ARPES) measurements and density functional theory (DFT) calculations, the electronic band structure of the topological insulator PbBi4Te4Se3 for ...both five-layer and seven-layer surface terminations is investigated. The measured and calculated band structure features are in good agreement and indicate two well-resolved topological surface states with distinct spatial localizations within bulk band gap of about 0.3 eV.
Numular headache is a chronic, mild to moderate, pressurelike pain in a circumscribed cranial area of approximately 2 to 6 cm in diameter. Pain usually is limited to the parietal region, although it ...may appear in any cranial site. It is a benign process of usually unknown origin.
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