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The consequence of carcinogenic and non-carcinogenic health risks of the heavy metal concentrations in street dust of North Cyprus is yet to be reported. This study is aimed at investigating the concentration of six different heavy metals' concentration explicitly: As, Cu, Zn, Ni, Cr, and Pb, along leading highways in Nicosia. The result obtained was analyzed using an X-ray fluorescent machine. Multivariate and statistical methods were applied for the data analysis using xlstat MS-excel; furthermore, index of geo-accumulation (Igeo) and human health risk assessment using exposure pathways as defined by United State Environmental Protection Agency (USEPA) pollution mode were also used for level assessment and health risk implications. The average (M ± SD) concentrations of the metals in the dust are as follows: As (17.48 ± 1.53 mg/kg), Cu (51.86 ± 8.60 mg/kg), Cr (321.14 ± 8.20 mg/kg), Pb (35.62 ± 8.54 mg/kg), Ni (64.79 ± 8.72 mg/kg), and Zn (136.13 ± 30.85 mg/kg). Variation coefficient, Vc, and principle component analysis (PCA) suggested that As, Cr, Ni, and Pb have same source of pollution emission from both natural and anthropogenic activities, Zn from traffic emission while Cu from natural source. However, the result was compared with other nearby towns bordering North Cyprus; all the metal shows similar pattern of pollution with the exception of Cr which is 5 and 11 times higher than street dust of Amman (Jordan) and Tokat (Turkey), respectively. Additionally, Igeo result has the following decreasing order: Zn > Cr > Pb > Ni > Cu > As and also revealed that the As, Cu, and Ni have originated from natural source. Cr has mix source: one from traffic and the other one from atmospheric deposition. Also, Pb is emitted from industrial pollution, whereas 80% of Zn are from traffic-related emissions. The non-carcinogenic health risk (hazard quotient (HQ) and hazard index (HI)) follows the order Cr > As>Ni > Pb > Zn > Cu for children and adults. It is found that the HI of As, Cu, Ni, Pb, and Zn is less one; hence, the street dust does not exhibit non-carcinogenic health risk. But that of Cr content is greater than one, with HI values of Cr 1.44E+02 and 1.55E+01 for children and adults, respectively. The result for carcinogenic health risk (total cancer risk (TCR)) has the following order: Pb (1.42E−05) > Cr (4.81E−09) > (Ni 1.35E−09) > As (1.96E−10). With all the values less than threshed hole limit of TCR ≥ 10−4, street dust does not possess carcinogenic health risk for the entire values of six heavy metals considered in this work. [ABSTRACT FROM AUTHOR]

Safeguarding groundwater from pollution is largely a global political decision. These decisions are basically supported by DRASTIC (D=Depth to water, R=Recharge, A=Aquifer media, S=Soil media, T=Topography, I=Impact of vadose zone, C=Hydraulic conductivity) analysis. Furthermore, water quality index (WQI) is an effective tool for groundwater quality evaluation and management. This study identifies the relationship between these two indices [i.e., pollution vulnerability index (PVI) and WQI]. The DRASTIC index of the study area was found to be from 60.4 to 178 characterized by very low, low, medium high, and very high vulnerability constituting of 12.88, 24.38, 34.11, 21.99, and 6.63% of the study area, respectively. In addition, the WQI of the area according to the analyzed parameters is between 10.19 and 55.63. It was established that a good correlation (61%) was found to exist between the two indices; which may be an indication that most pollutants present in the groundwater are likely due to anthropogenic activities on the land surface. [ABSTRACT FROM AUTHOR]

All groundwater is vulnerable to pollution, but the level of susceptibility depends on the spatial peculiarities of a region. Among the numerous vulnerability assessment methodologies, the geographical information system-based DRASTIC model is the most sophisticated and achieves reliable results even in complex areas. Fractured-rock aquifers are not only complex, but they are also potential sources of radioactive and other types of waste and are liable to high recharge rates. Hence, they can serve as a conduit for fluid (and potentially) contaminants. Therefore, in this study, a new parameter, 'fracture media' ( F), is fashioned to replace the weakest parameter (i.e. depth to water, D) in the standardized DRASTIC model to create a new model (FRASTIC) for the complex fractured aquifer system. The proposed model was tested on a case study area (Kano, Nigeria), and the FRASTIC minimum and maximum indices obtained were in the range of 63-170. The region was characterized as having very low (covering 0.16% of the total study area), low (55.52%), medium (42.53%), and high (1.79%) vulnerability based on the standardized classification system. In addition, the modified FRASTIC model was further developed using the sensitivity analysis (SA) and recorded the highest vulnerable area coverage (32.86%) within Kano. Thus, the modified FRASTIC model is appropriate for the complex nature of the study area because it contributes appreciably to defining the vulnerable zones. The single-parameter SA was employed to obtain effective weights for two modified models, which were then implemented to improve efficacy. Conventional nitrate validation indicated that there is a strong correlation between nitrate and vulnerability for the modified models. In addition, a new approach for identifying the relationship between the water quality and vulnerability indices was developed by this study and was proven to be an effective validation tool. [ABSTRACT FROM AUTHOR]

Knowledge of fractures and their connectivity in geologic media is paramount to groundwater resource management. However, the theory of connectivity between the fractures and their measurement techniques, and its application in modelling are still under great debate. Various studies indicated that the aquifers of the basement complex rocks in Kano are regolith and the fractures are connected at various depths. However, no study has stated the extent (spread) of the underlain fractures, their position, the connectivity between the fractured zones and whether or not all the fractured rock aquifers are productive (water available within fractures). Therefore, this study was undertaken with a view to addressing these challenges. It is established using the GIS-based spatial analysis approach that 52.28 % of the underlain aquifers are productive. The minimum and maximum depths of the underlain fractured rocks are 19.8 and 50.6 m, respectively. Only 19 % of the total study area is unproductive while 42.35 % of the underlain basement complex is characterized by fractures. These fractures are completely saturated. [ABSTRACT FROM AUTHOR]

Septoria tritici blotch (STB) caused by the fungus Zymoseptoria tritici (formerly known as Mycosphaerella graminicola) is currently the most important foliar disease of durum wheat (Triticum turgidum subsp. durum) in Tunisia, causing serious yield losses and affecting grain quality. Resistance breeding in durum wheat to STB can provide an effective, economic and environmentally-safe strategy to reduce yield losses. However, this is hampered by a lack of resistance sources, and a limited understanding of Z. tritici pathogenicity. Here, we report the identification of nine resistant accessions to STB upon field inoculation of 144 old local durum wheat accessions with a virulent isolate "TunBz-1". Crosses between the resistant accessions and evaluation of F2 progenies for their reaction to TunBz-1 led to the identification of four new resistant genes, associated with Azizi27, Agili37, Agili39 and Derbessi12 landrace accessions. Random distribution of the resistant accessions in an AFLP based-dendrogram of 123 old durum wheat accessions suggested independent resistance gene-evolution. Based on the identified resistance sources, the analysis of the virulence spectrum of 55 Z. tritici isolates collected from different durum wheat-growing regions in Tunisia showed a highly significant genotype-by-isolate interaction. Furthermore, pathotype variability among Z. tritici isolates was low as the isolates were classified into two groups (I and II) that showed differential reaction on the accession Azizi27. Our results show that the old local durum wheat germplasm might harbor novel resistance genes that can be deployed in durum wheat breeding programs. [ABSTRACT FROM AUTHOR]

Groundwater vulnerability assessment is an important task in water resources and land management. The most sophisticated among the vulnerability assessment techniques is the GIS-based DRASTIC model. However, despite its popularity, it is marred with excessive subjectivity glitches; little research has been conducted to address the shortcomings associated with this method. This study investigates various issues regarding the application of the GIS-based DRASTIC model through a critical review of relevant literatures. It is revealed that all the DRASTIC parameters are equally significant irrespective of their assigned weights. On the contentious quantile classifications, however, a categorical classification defined by 'very low', 'low', 'medium', 'high', and 'very high' was suggested for standardization. Based on the studied literatures, it was established that 46 % of 977 million km of land assessed globally fell within moderate to high vulnerability category-a land cover bigger than the cultivated lands obtainable in all the countries around the world except the United States, India, China, Russia, Brazil, Canada and Australia. [ABSTRACT FROM AUTHOR]

Objectives: The SteatoTest, fatty liver index (FLI) and hepatic steatosis index (HSI) are clinico-biological scores of steatosis validated in general or selected populations. Serum adiponectin (s-adiponectin) and retinol binding protein 4 (s-RBP4) are adipokines that could predict liver steatosis. We investigated whether the Steatotest, FLI, HSI, s-adiponectin and s-RBP4 could be valid predictors of liver steatosis in type-2 diabetic (T2D) patients.Methods: We enrolled 220 consecutive T2D patients. Reference standard was 3.0 T (1)H-MR spectroscopy (corrected for T1 and T2 decays). Intraclass correlation coefficients (ICCs), Kappa statistic measures of agreement, receiver operating characteristic (ROC) curves were assessed.Results: Median liver fat content was 91 mg triglyceride/g liver tissue (range: 0-392). ICCs among the Steatotest, FLI, HSI, s-adiponectin, s-RBP4 and spectroscopy were low: 0.384, 0.281, 0.087, -0.297 and 0.048. Agreement between scores and spectroscopy was poor (Kappa range: 0.042-0.281). The areas under the ROC curves were low: 0.674, 0.647, 0.637, 0.616 and 0.540. S-adiponectin and s-RBP4 levels were strongly related to the presence of diabetic nephropathy (P = 0.0037 and P = 0.004; Mann-Whitney).Conclusion: The SteatoTest, FLI, HSI, s-adiponectin, s-RBP4 are not valid predictors of steatosis in T2D patients. Clino-biological markers cannot replace (1)H-MR spectroscopy for the assessment of liver fat in this population.Key Points: (1) H-MR spectrosopy can reliably estimate the weight fraction of liver steatosis. Type-2 diabetes provides an interesting model for assessing liver steatosis. Clinico-biological markers seem to be invalid predictors for steatosis in type-2 diabetes. [ABSTRACT FROM AUTHOR]

The paper is devoted to the study of uncertainties when studying buildings under seismic loading. These uncertainties are related to the simplifications used when constructing the model (model uncertainties) and to the numerical data needed at the computation stage (data uncertainties). It has been shown in previous papers that nonparametric models are able, in the case of linear dynamics, to deal simultaneously with these two kinds of uncertainties. The paper presents an extension of this kind of model by taking into account a “mixed” approach for concrete frame structures, which uses a nonparametric model for the part of the structure which behaves linearly and a parametric approach for the parts of the structure (plastic hinges) which behave non-linearly. A numerical application is presented in the case of a residential building. [ABSTRACT FROM AUTHOR]

Three Lactococcus strains ( Lactococcus ssp . lactis var . diacetylactis, Lactococcus ssp . lactis cremoris and Lactococcus ssp . lactis var . lactis) isolated from the Tunisian lben were grown at constant pH on CSL medium in stirred fermentors for lactic starters production. The agitation required to homogenate alkali used to pH control should be low because it affects the Lactococcus growth. Scale up from 20-liter fermentor to 400-liter fermentor was carried out at constant impeller tip speed below 150 cm s−1. The CSL supplementation and fed-batch with glucose increased the yield in the upper 1010 cfu/ml. The consumed glucose during fermentation was converted into lactic acid and cell. Before fed-batch, the maximum specific growth rate of Lactococcus ssp . lactis var . diacetylactis was around 1 h−1 and the number of cells increased 20 to 40 times according to inoculum size. After fed-batch, the glucose consumption rate remains constant but specific growth rate decreased and number of cell trebled only. [ABSTRACT FROM AUTHOR]

We describe a method for the isolation of spontaneous haploid tomato plants from greenhousegrown seedlings obtained from crosses involving a transgenic parental line in which a counter-selectionable chimeric gene has been introduced. Transgenic seeds transformed with the aux2 gene, a gene of Agrobacterium rhizogenes that transforms naphthalene acetamide (NAM) into naphthalene acetic acid (NAA), did not develop roots in the presence of NAM, whereas wildtype tomato seeds developed a normal rooting system in its presence. Transgenic plants homozygous for aux2 (cv 'UC82b') were used to pollinate male-sterile ( ms322) tomato plants (cv 'Apedice'). Using NAM as a toxic substrate to kill heterozygous diploid plants carrying aux2, we selected for three maternal haploid plants resulting from the development of the female nucleus without fertilization. Maternal haploid selection using the aux2 marker was less efficient than the visual screening of haploid plants displaying recessive morphological markers of the female parent, but provided evidence for the feasibility of haploid selection in species for which no morphological markers are available. [ABSTRACT FROM AUTHOR]

The temperature dependence of tensile creep of butadiene rubber (BR) loaded with different concentrations of carbon black ISAF was tested under different applied stresses. The steady creep rate showed a dependence on stress, temperature and carbon black content. The energy-activating steady creep was of order 0.15 eV for samples containing 20 phr of ISAF carbon black and reached a value of 0.37 eV for samples containing 80 phr of carbon black. This was attributed to the blocking of motion of the molecular segments by the carbon black. This view point was confirmed by the activation volume which was found to decrease with the increase of carbon black content. The stress sensitivity parameter was found decrease from 3.4 for samples containing 20 phr to 1.8 for samples containing 80 phr of carbon black. [ABSTRACT FROM AUTHOR]

The effect of electric field on the creep characteristics and the corresponding parameters such as instantaneous strain, strain rate, activation energy, activation volume, stress-sensitivity parameter and viscosity was investigated. [ABSTRACT FROM AUTHOR]