Modelling rock slope behaviour and evolution with reference to Northern Spain and Southern Jordan

The geomorphological behaviour of steep jointed rock slopes has been studied using distinct element computer models. In order to model steep slopes effectively, methodologies need to be combined from the studies of environmental modellers, geomorphologists and engineers. The distinct element method is ideal for the study of the development of jointed rock masses, where the failure is controlled by the nature of the discontinuities. Theoretical modelling identified that block size is a key control affecting the deformation of rock masses. Deformation of rock masses with smaller block assemblages is greater than for rock masses composed of larger block sizes. This is due to the increased magnitude of joint normal closure. Catastrophic failure is less likely in slopes with smaller block sizes because the shear strength is greater in a closely jointed rock mass. These slopes are more likely to undergo gradual deformations. Block-size effects are also responsible for influencing the failure mechanism of rock masses. As block size decreases, the magnitude of block rotation increases and the failure mechanism changes from sliding to toppling. The effect of slope scale on the deformation properties of the rock masses has also been investigated. Two field locations, the Picos de Europa mountains, northern Spain and Wadi Rum, southern Jordan, have been chosen to provide a link between the theoretical modelling and classic rock landforms which are controlled by the discontinuity geometry. Given the sporadic and infrequent occurrence of failure events at the field sites, a computer modelling approach has been adopted to analyse slope behaviour. In the Picos de Europa, slope deformations are deep-seated, with sliding and toppling being the dominant modes of failure. Much of the slope deformation in these mountains is a result of post-glacial rock-slope deformation. The sandstone inselbergs of Jordan show a range of morphologies from rounded hills to vertical cliffs. The morphology of the inselbergs is related to the intact rock strength; stronger Red lshrin sandstone forms vertical slopes, whereas the weaker Disi sandstone forms rounded domes. Jointing in the area is sub-vertical with horizontal bedding and computer simulations have shown that toppling is the dominant mode of failure in these inselbergs. Comparison of computer model output suggests that different failure mechanisms have distinct failure signatures. Catastrophic, deep-seated failures are characterised by a long period of acceleration as the failure propagates through the rock mass and infinite velocity is reached. Non-catastrophic slope movements, such as self-stabilising topples, are characterised by short periods of acceleration followed by small creep movements at a constant velocity. Computer modelling has indicated that scale effects do exist in the modelled rock masses from the Picos de Europa and particularly Wadi Rum. In areas where jointing is constant, the relative block size of the rock mass decreases as slope scale increases. The greater numbers of blocks along with greater in situ stresses influence the failure of the slope. Cosmogenic dating was used to temporally constrain UDEC model output and provide a better understanding of rock slope failure mechanisms in the Picos de Europa and Wadi Rum. Dating indicated delayed paraglacial adjustment was the triggering mechanism for slope failure in the Picos de Europa, whereas failures in Wadi Rum appeared to be closely linked with wetter climatic conditions

The History of Lobotomies: Examining its Impacts on Marginalized Groups and the Development of Psychosurgery

Frontal lobotomies, which are defined as the lesioning of the frontal lobe from the rest of the brain, were performed extensively from the 1930s to the 1960s in Europe and the United States, significantly impacting psychology and psychosurgery. The history of frontal lobotomies features many different practitioners with diverse methods; however, the overwhelming majority of popular lobotomists committed unethical actions by today’s standards that led to the direct marginalization of specific demographics. Using a framework guided by an exploration of those historically disempowered by the performance of lobotomies, this review article traces the lobotomy’s historical progression, focusing on the unethical treatment of, and the absence of informed consent from vulnerable patients. The practice of lobotomies is today considered unethical; however, its historical occurrence stigmatized psychosurgery, psychology, and science as a whole, the scars of which are still, to some extent, present for current practitioners in the field

Bioactive factors in microbial biomass have the capacity to offset reductions in the level of protein in the diet of black tiger shrimp, Penaeus monodon

A factorial experiment was conducted with black tiger shrimp (Penaeus monodon) juveniles to determine the effects of varying protein inclusion in the diet and also varying inclusion of a microbial biomass on growth, feed and nutrient utilization when fed in indoor laboratory conditions. The growth performance of the shrimp improved with increasing diet protein level. However, in the absence of the added microbial biomass, this growth performance plateaued at the 480. g/kg protein level. The addition of the microbial biomass improved growth at each inclusion level of both protein and microbial biomass. No plateau in growth was observed with the addition of the microbial biomass. Improvements in feed conversion were seen with increasing dietary protein levels and also the inclusion of the microbial biomass. Examination of the feed intake of each treatment supports that there was a combined effect of an increase in feed intake and improvements in feed conversion that contributed to the improvements in growth performance with the use of the microbial biomass, but the increases in dietary protein level largely influenced growth through improvements in feed conversion

In vitro identification and in silico utilization of interspecies sequence similarities using GeneChip(® )technology

BACKGROUND: Genomic approaches in large animal models (canine, ovine etc) are challenging due to insufficient genomic information for these species and the lack of availability of corresponding microarray platforms. To address this problem, we speculated that conserved interspecies genetic sequences can be experimentally detected by cross-species hybridization. The Affymetrix platform probe redundancy offers flexibility in selecting individual probes with high sequence similarities between related species for gene expression analysis. RESULTS: Gene expression profiles of 40 canine samples were generated using the human HG-U133A GeneChip (U133A). Due to interspecies genetic differences, only 14 ± 2% of canine transcripts were detected by U133A probe sets whereas profiling of 40 human samples detected 49 ± 6% of human transcripts. However, when these probe sets were deconstructed into individual probes and examined performance of each probe, we found that 47% of human probes were able to find their targets in canine tissues and generate a detectable hybridization signal. Therefore, we restricted gene expression analysis to these probes and observed the 60% increase in the number of identified canine transcripts. These results were validated by comparison of transcripts identified by our restricted analysis of cross-species hybridization with transcripts identified by hybridization of total lung canine mRNA to new Affymetrix Canine GeneChip(®). CONCLUSION: The experimental identification and restriction of gene expression analysis to probes with detectable hybridization signal drastically increases transcript detection of canine-human hybridization suggesting the possibility of broad utilization of cross-hybridizations of related species using GeneChip technology

Using near-infrared reflectance spectroscopy to predict the digestible protein and digestible energy values of diets when fed to barramundi, Lates calcarifer

This study examined the potential of using near-infrared spectroscopy (NIRS) to predict nutrient digestibility parameters (digestible protein and digestible energy) of compound diets when fed to barramundi. A series of 60 diets were assessed for their protein and energy digestibilities in a series of five experiments over a 5-year period from 2009 to 2014. Considerable variance was observed in the digestibility parameters of diets across the experiments, providing a suitable range in diet digestible protein and digestible energy values from which to develop a NIRS calibration. Samples of the same diets were also scanned using a diode array near-infrared spectrophotometer (DA-NIRS). The spectra were obtained by the DA-NIRS and were chemometrically calibrated against the digestible value data using multivariate analysis software. The results in terms of standard error of cross-validation (SECV), residual prediction deviation (RPD) and correlation coefficient (R2) show good relationships (R2 > 0.8) between the predicted and observed parameters for both the digestible protein and digestible energy parameters assessed. This study therefore demonstrates that it is possible to use NIRS technology to provide rapid estimates of the digestible protein and digestible energy values of compound diets for barramundi in near real time.&nbsp

A study of the discrete and interactive effects of different polysaccharides on the digestibility of diets fed to barramundi (Lates calcarifer)

This study examined the single, paired and combined inclusion effect of a range of different polysaccharide types on the dry matter, protein and energy digestibility of diets fed to barramundi (Lates calcarifer). The different polysaccharides included pregelled starch, cellulose, lignin and pectin. There were significant differences among the digestibility parameters of the diets with the different inclusion levels of each of the different polysaccharide types. Using a manova analysis, effects were noted for polysaccharide type, inclusion level and interaction terms on the digestibilities of dry matter, protein and energy. Cellulose addition resulted in a reduction in both dry matter and energy that was largely commensurate with its inclusion level, but its effect on protein digestibility was marginal. Starch had the least effect on any of the digestibility parameters of all the polysaccharide types examined. Pectin had the largest effect on dry matter, while lignin had the greatest impact on diet protein and energy digestion. In the diets with paired combinations of polysaccharides, lignin and pectin were responsible for negatively synergistic interactions in all digestibility parameters. These results show that different polysaccharide classes can have distinctly different effects on diet digestibility parameters. © 2015 John Wiley & Sons Ltd

The combined effects of diet, environment and genetics on pigmentation in the Giant Tiger Prawn, Penaeus monodon

The colour of prawns, particularly the Giant Tiger Prawn Penaeus monodon, is highly desired and fetches premium market prices. Prawn pigmentation is influenced by the interaction of a range of factors, including the amount of dietary carotenoid, the distribution of hypodermal pigments, and genetics. These aspects have been studied in isolation, but there is limited knowledge on how these components interact to influence prawn pigmentation. This study tracked the colour of prawns that had been fed four different levels of dietary astaxanthin (Axn) over 6. weeks, and then transferred to either black or white coloured tanks. The dietary influence on colour was slow and had only developed after 6. weeks. Meanwhile the effect of background colour was rapid, within 15. min. Results showed that diet and background colour work in combination to affect prawn colour. The poorest colour was recorded in prawns fed without dietary Axn and transferred to white substrates, and this colour was improved by the addition of dietary Axn. Animals fed without dietary Axn and exposed to black substrates showed an intermediate colour, and this was further improved by the addition of dietary Axn. The best colour was recorded in prawns fed 100. mg/kg Axn and exposed to black substrates. The abundance of the epithelial pigment protein crustacyanin (CRCN) was not correlated with prawn colour, suggesting that this protein does not regulate the modifications in response to background colour. Finally, the effect of substrate exposure was assessed on farmed prawns, and indicated a small positive effect on colour during harvesting. These data demonstrate that while short term exposure to black substrates can have positive effects on prawn colour, dietary Axn supplementation can both improve pigmentation of animals exposed to black substrates, and prevent the negative effects of exposure to white substrates