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SUMMARY Galvanic distortion of magnetotelluric (MT) data is a common effect that can impede the reliable imaging of subsurface structures. Recently, we presented an inversion approach that includes a mathematical description of the effect of galvanic distortion as inversion parameters and demonstrated its efficiency with real data. We now systematically investigate the stability of this inversion approach with respect to different inversion strategies, starting models and model parametrizations. We utilize a data set of 310 MT sites that were acquired for geothermal exploration. In addition to impedance tensor estimates over a broad frequency range, the data set also comprises transient electromagnetic measurements to determine near surface conductivity and estimates of distortion at each site. We therefore can compare our inversion approach to these distortion estimates and the resulting inversion models. Our experiments show that inversion with distortion correction produces stable results for various inversion strategies and for different starting models. Compared to inversions without distortion correction, we can reproduce the observed data better and reduce subsurface artefacts. In contrast, shifting the impedance curves at high frequencies to match the transient electromagnetic measurements reduces the misfit of the starting model, but does not have a strong impact on the final results. Thus our results suggest that including a description of distortion in the inversion is more efficient and should become a standard approach for MT inversion.

Thermal tolerance parameters of thirteen ornamental fish species (Carassius auratus, Cyprinus carpio: koi, Brachydanio rerio, Puntius tetrazona, Garra rufa, Poecilia latipinna, P. reticulata, Pterophyllum scalare, Labidochromis caeruleus, Cyrtocara moorii, Carydoras paleatus, Trichogaster trichopterus and Hypostomus plecostomus) at three acclimation temperatures (20, 24 and 28 °C) were determined in this study. The CTMin values of the species ranged from 2.55–6.54 °C (C. auratus) to 11.66–13.94 °C (P. tetrazona), while CTMax values ranged from 33.91–37.51 °C (P. cory) to 39.71–41.80 °C (P. reticulata). The acclimation response ratio (ARR) values between 20 and 28 °C acclimation temperature (AT) ranged from 0.18 (H. plecostomus) to 0.63 (B. rerio) for CTMin, while these values ranged between 0.17 (G. rufa) and 0.67 (P. tetrazona) for CTMax values. Thermal tolerance polygon was widest in C. auratus (281 °C2) and narrowest in P. tetrazona (188 °C2). Despite being in the same family (Cyprinidae), it is interesting and unusual that C. auratus is a typical eurythermal and P. tetrazona is a typical stenothermal species. C. auratus and C. carpio followed by G. rufa, P. latipinna and B. rerio are the species which are advantageous in terms of aquaculture due to their wide temperature tolerance range and high ARR values. © 2018 Elsevier B.V. FDK-2014-2820 The authors would like to thank the research fund of the Cukurova University , (Turkey) for financial support to the study with Project No: FDK-2014-2820 . All animals used in this study were reared according to animal use and care guidelines established by Turkish Ministry of Environement and Forestry (Animal Welfare Assurance No: 28914). The authors declare no conflict of interest.

While the Ultra Wide-Band Magnetotelluric technology (10,000Hz - 50,000 seconds) covers AMT, MT and LP bends in simultaneously measured time series, many research and exploration projects use dedicated MT (300Hz to 10,000 seconds) or LP (10 seconds - 50,000 seconds) systems. This is usually dictated by available equipment or a traditional approach to deep target studies. Surface anomalies (up to 2-5km) formed by conductive mineral bodies or fault systems considered to be less important and are often completely ignored during deep lithospheric studies. The upper layers conductivity is being estimated and averaged over the whole survey area. As it is very well known, the Magnetotelluric sounding signal measured on the surface represents an apparent resistivity at a depth dependent on frequency and conductivity of averaged ground thickness above. This assumption works generally well in smoothly layered geology, but might integrate an error in estimations and inversions in more complicated situations. In our previous studies we observed an effect of an upward shift of anomalies obtained after inversion of smaller grid size data for long period measurements. This seems to happen when the localized 3D conductive bodies are becoming dominant over the average layer conductivity and it cannot be assumed as a homogeneous thickness. In this study, our intention is analysing the efficient grid size that would be effective for MT band and LP band surveys. To achieve our estimated results, we designed a geoelectrical model that would be typical for Canadian shields with different grid sizes for MT band signal and LP band signals. We did run inversions using ModEM and observed vertical fit of inversion results to an original model.

This study was conducted to determine the potential nutritional value of heated culban (Vicia peregrina) seed at the different levels (0, 10, 20 and 30%) in diet as a plant protein source for Nile tilapia (Oreochromis niloticus). The fish fed experimental diets grew from an initial body weight of 38 g to a final body weight of 120 g for a rearing period of 80 days. Growth parameters, feed utilization and meat proximate composition were found similar in all experimental groups. It is concluded that culban seed can be successfully used as an inexpensive plant protein source at least up to a level of 30% in tilapia diets without adverse effects on fish performance. © Medwell Journals, 2010.

The effects of unilateral testicular torsion on the blood flow of the contralateral testis were investigated. Fourteen adult male dogs were recruited. Seven dogs underwent unilateral testicular torsion of 4 h duration, and the other seven dogs had a control operation. Testicular blood flow was determined by colour Doppler ultrasonography before and after the testicular torsion. Bilateral orchidectomy was performed at the end of the study and histopathological changes were evaluated. Values of peak systolic velocity, end diastolic velocity, and resistive index were not statistically significant between ipsilateral and contralateral testes in the study group (p > 0.05). On comparison with the control group, blood flow in the contralateral testes showed no statistically significant difference (p > 0.05). Oedema and congestion were seen on ipsilateral testes in the study group. No histopathological changes were noted on the contralateral testes. Minimal oedema and congestion secondary to manipulation were found in the control operation testes. We conclude that unilateral testicular torsion does not decrease contralateral testicular blood flow as shown by colour Doppler ultrasonography.

This study was conducted to compare effects of aquria made of glass or fiberglass on growth and pigmentation in goldfish, Carassius auratus (initial weight of 8.1 g) and electric yellow cichlid, Labidochromis caeruleus (initial weight of 0.47 g) for a rearing period of 80 days. Skin colour assessment was performed by reflectance spectroscopy with transformation into colour parameters based on tristimulus values, L (lightness), a (redness) and b (yellowness). A lower L and a higher a, b was obtained on skin of goldfish reared in fiberglass aquarium compared to those in glass one (p0.05). Growth performance, feed conversion ratio and survival ratio in both species were not affected by the aquarium types (p>0.05). Aquarium made of fiberglass should be preferred for goldfish rearing as skin colour is significantly improved in this media. © Medwell Journals, 2010.