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A simple decay-spectroscopy station at CRIS-ISOLDE
No full textAbstractA new decay-spectroscopy station (DSS2.0) has been designed by the CRIS collaboration for use at the radioactive ion beam facility, ISOLDE. With the design optimised for both charged-particle and γ-ray detection, the DDS2.0 allows high-efficiency decay spectroscopy to be performed. The DSS2.0 complements the existing decay-spectroscopy system at the CRIS experiment, and together provide the ability to perform laser-assisted nuclear decay spectroscopy on both ground state and long-lived isomeric species. This paper describes the new decay-spectroscopy station and presents the characterisation studies that have recently been performed
Protective effect of olive and juniper leaves extracts on nephrotoxicity induced by thioacetamide in male mice
No full textAbstractThis study, for the first time, evaluates the effect of olive and juniper leaves extracts and their combination on thioacetamide (TAA)-induced nephrotoxicity in male mice. The experimental mice were divided into eight groups. Group 1 was served as control. Group 2 was exposed to TAA. Group 3 was treated with TAA and olive leaves extract. Group 4 was subjected to TAA and juniper leaves extract. Group 5 was exposed to TAA and olive and juniper leaves extracts. Groups 6, 7 and 8 were treated with olive, juniper, and olive and juniper leaves extracts respectively. In mice treated with only TAA, significant increases of blood urea nitrogen and uric acid were observed after six weeks. Moreover, levels of serum creatinine, blood urea nitrogen and uric acid were statistically increased in mice administrated with only TAA for twelve weeks. Insignificant alterations in levels of these haematobiochemical parameters were noted in other treated groups after six and twelve weeks. Histopathological evaluations of renal sections from mice treated with only TAA for twelve weeks showed severe damage of the renal corpuscles. Furthermore, the renal sections from mice treated with TAA and olive leaves extract, TAA and juniper leaves extract, TAA and olive and juniper leaves extracts, olive leaves extract, juniper leaves extract, and olive and juniper leaves extracts showed normal structures. In addition, it is conceivable therefore, that these extracts exhibit protective influences against TAA-induced nephrotoxicity, probably mediated through the antioxidative pathway roles
Intercropping leek (Allium porrum L.) with dyer’s woad (Isatis tinctoria L.) increases rooted zone and agro-ecosystem retention of nitrogen
No full textAbstractNitrate leaching can be high in organic vegetable production. Late-harvested crops like leek limit the use of autumn catch crops. The aim of this study was to investigate the growing of a combination of a deep-rooted catch crop and a shallow-rooted vegetable to reduce the risk of nitrate leaching. We compared a leek sole crop (S) with two intercropped systems of leek and early-sown dyer’s woad (five weeks after leek planting) (IE) or late-sown dyer’s woad (eight weeks after leek planting) (IL) in two seasons: 2012 and 2013. To reveal root and resource competition, leek with dyer’s woad rows left empty (Semp), and early and late-sown dyer’s woad with leek rows left empty (DEemp, DLemp) were included. Yield, dry above-ground biomass, aboveground N accumulation and soil inorganic N (Ninorg) were measured as well as root growth by use of minirhizotrons to 2.3m soil depth. Results showed that the marketable yield of leek in IE and IL systems was comparable with the yield in the S system when calculated per length of leek row. The Relative Competition Index (RCI) revealed that interspecific competition facilitated the growth of leek but hampered that of dyer’s woad. The rooted zone increased from 0.5m in the S system to more than 2m depth in those of the intercropped systems. Dyer’s woad ceased growing above ground but kept growing below ground after crop harvest and extended roots under the leek root system in 2012. Intercropping increased the root intensity of late-sown dyer’s woad after leek harvest in the 0.75–1.75m soil layer compared to dyer’s woad growing alone (DLemp), while the root depth was not affected. The intercropped system with early-sown dyer’s woad reduced soil Ninorg by 52kgha−1 relative to the sole-cropped system, and dyer’s woad accumulated 48kgNha−1 in aboveground biomass at harvest in 2013. Late-sown dyer’s woad had fewer roots, left higher soil Ninorg and had lower aboveground N accumulation than early-sown dyer’s woad until the following spring. Therefore, early-sown dyer’s woad is applicable in an organic intercropped system with high yields of leek to decrease the risk of nitrate leaching
From grid to field: Assessing quality of gridded weather data for agricultural applications
No full textAbstractHigh quality measured weather data (MWD) are not available in many agricultural regions across the globe. As a result, many studies that dealt with global climate change, land use, and food security scenarios and emerging agricultural decision support tools have relied on gridded weather data (GWD) to estimate crop phenology and crop yields. An issue is the agreement of GWD with MWD and the degree to which this agreement may influence the utility of GWD for agricultural research. The objectives of this study were: (i) to compare the agreement of two widely used gridded weather databases (GWDs) (Daymet and PRISM) and MWD, (ii) to evaluate their robustness at simulating maize growth and development, and (iii) to examine how GWD compare relative to weather data interpolated from existing meteorological stations for which MWD are available. The U.S. Corn Belt, a region that accounts for 43 and 34% of respective global maize and soybean production, was used as a case of study because of its dense weather station network and high-quality MWD. Historical daily MWD were retrieved from 45 locations across the region, resulting in ca. 1300 site-years. To test the accuracy of GWDs, separate simulations of maize yield and development were performed, separately for the two GWDs and MWD, using a well-validated maize crop model. For both GWDs, small biases were observed for temperature and growing degree-days in relation with MWD. However, accuracy was much lower for relative humidity, precipitation, reference evapotranspiration, and degree of seasonal water deficit. There was close agreement in duration of vegetative and reproductive phases between GWD and MWD, with root mean square error (RMSE) ranging from 3 to 7days for the different crop phases and GWDs. However, robustness of GWDs to reproduce maize yields simulated using MWD was lower as indicated by the RMSE (18 and 24% of average yield for Daymet and PRISM, respectively). There was also a high proportion of site-years (20 and 32% for Daymet and PRISM, respectively) exhibiting a yield deviation >15% in relation to the yield simulated using MWD. Data interpolation using a dense weather station network resulted in lower RMSE% for simulated phenology and yields relative to GWDs. Findings from this study indicate that GWD cannot replace MWD as a basis for field-scale agricultural applications. While GWD appear to be robust for applications that only require temperature for prediction of crop stages, GWD should not be used for applications that depend on accurate estimation of crop water balance, crop growth, and yield. We propose that the evaluation performed in this study should be taken as a routinary activity for any research or agricultural decision tool that relies on GWD
Diversification and family control as determinants of performance: A study of listed business groups
No full textAbstractThe study analyses the individual and joint impact of family control and diversification on the performance of major Spanish corporations, considering the nature of the ultimate owner of non-family groups. The study uses a sample of ninety-nine Spanish corporations, each comprising a parent company listed on the stock exchange and a set of subsidiaries. Heckman's two-step correction is used to eliminate selection bias and the endogeneity of family ownership. Different models are contemplated in which we analyse the impact of both diversification and the family nature of a business on performance, established as Tobin's q-value. The results show how family control has a negative impact on Tobin's q-value, and that differences are greater between family groups and non-family groups controlled by banks and/or foreign agents. They also show how diversification does not affect the creation of value either individually or considering the possible moderating effect of family ownership
Development and evaluation of a self-cleaning custom-built auto sampler controlled by a low-cost RaspberryPi microcomputer for online enzymatic activity measurements
No full textAbstractA fully automated on-site device (SAMP-FIL) that enables water sampling with simultaneous filtration and effective cleaning procedures of the device's components was developed and field-tested. The SAMP-FIL was custom-built using commercially available components and was controlled by a RaspberryPi single-board computer operating open-source software. SAMP-FIL was designed for sample pre-treatment with minimal sample alteration to meet the requirements of on-site measurement devices that cannot handle coarse suspended solids within the measurement procedure or cycle. A highly effective cleaning procedure provides a fresh and minimally altered sample for the connected measurement device. The construction and programmed software facilitates the use of SAMP-FIL for different connected measurement devices. The SAMP-FIL sample pretreatment was tested for over one year for rapid and on-site enzymatic activity (beta-d-glucuronidase, GLUC) determination (BACTcontrol) in sediment-laden stream water. The formerly used proprietary sampling set-up was assumed to lead to significant damping of the measurement signal due to its susceptibility to clogging, debris accumulation and bio-film accumulation. The implementation of SAMP-FIL considerably increased the error-free running time and measurement accuracy of BACTcontrol devices. This paper describes how low-cost microcomputers, such as the RaspberryPi, can be used by operators to substantially improve established measuring systems via effective sampling devices. Furthermore, the results of this study highlight the importance of adequate sample pretreatment for the quality of on-site measurements
Assessment of insulin sensitivity by the hyperinsulinemic euglycemic clamp: Comparison with the spectral analysis of photoplethysmography
No full textAbstractAimsWe compare spectral analysis of photoplethysmography (PTG) with insulin resistance measured by the hyperinsulinemic euglycemic clamp (HEC) technique.Material and MethodA total of 100 nondiabetic subjects, 43 men and 57 women aged 20–63years, 30 lean, 42 overweight and 28 obese were enrolled in the study. These patients underwent an examination with HEC, and an examination with the PTG spectral analysis and calculation of the PTG Total Power (PTG-TP). Receiver-operating characteristic (ROC) curves were constructed to determine the specificity and sensitivity of PTG-TP in the assessment of insulin resistance.ResultsThere is a moderate correlation between insulin sensitivity (M-value) and PTG-TP (r=− 0.64, p<0.0001). The ROC curves showed that the most relevant cutoff to the whole study group was a PTG-TP>406.2. This cut-off had a sensitivity=95.7%, specificity =84,4% and the area under the ROC curve (AUC)=0.929 for identifying insulin resistance. All AUC ROC curve analysis were significant (p<0.0001).ConclusionThe use of the PTG-TP marker measured from the PTG spectral analysis is a useful tool in screening and follow up of IR, especially in large-scale studies
Safety evaluation of substituted thiophenes used as flavoring ingredients
No full textAbstractThis publication is the second in a series by the Expert Panel of the Flavor and Extract Manufacturers Association summarizing the conclusions of its third systematic re-evaluation of the safety of flavorings previously considered to be generally recognized as safe (GRAS) under conditions of intended use. Re-evaluation of GRAS status for flavorings is based on updated considerations of exposure, structural analogy, metabolism, pharmacokinetics and toxicology and includes a comprehensive review of the scientific information on the flavorings and structurally related substances. Of the 12 substituted thiophenes reviewed here, 11 were reaffirmed as GRAS based on their rapid absorption, metabolism and excretion in humans and animals; the low estimated dietary exposure from flavor use; the wide margins of safety between the conservative estimates of intake and the no-observed-adverse effect levels; and the lack of significant genotoxic and mutagenic potential. For one of the substituted thiophenes, 3-acetyl-2,5-dimethylthiophene, it was concluded that more detailed exposure information, comparative metabolism studies and comprehensive toxicity data, including an in-depth evaluation of the mechanism of action for any adverse effects observed, are required for continuation of its FEMA GRAS™ status. In the absence of these data, the compound was removed from the FEMA GRAS list
Experimentally validated numerical study of gas-solid vortex unit hydrodynamics
No full textAbstractA three-dimensional numerical analysis of the flow in a Gas-Solid Vortex Unit (GSVU) is carried out. The numerical model is first validated by comparing the bed pressure drop and solids velocity with experimental data. Next, the influence of gas flow rate, solids density, and particle diameter on the pressure drop, solids velocity, bed void fraction and slip velocity between the two phases is studied. A stable, solids bed is achieved for the entire range of gas flow rates tested (0.1–0.6Nm3/s). No particle entrainment is observed when varying the solid density (1800–450kg/m3) or the particle diameter (2–0.5mm). A shift to bubbling fluidization regime is observed for small particle diameters (0.5mm). The observed changes in the GSVU flow patterns are discussed by analyzing the changes in the cumulative centrifugal to drag force ratio over the bed
