Lightning protection scenarios of communication tower sites; human hazards and equipment damage

This paper provides comprehensive analysis on the lightning protection scenarios in 48 communication and broadcasting towers situated in similar isokeraunic contours in Sri Lanka at 79°–81° East and 5°–10° North. The investigation has been conducted to study the hazardous environment created on the tower and in the neighbourhood in the event of a lightning strike to the tower. The results show that a direct strike to an antenna structure in a metallic tower is rare irrespective of the presence of an air-termination or a down conductor. However, side flashing or arcing to antenna structures is highly possible once the air-termination and/or down conductor is installed and attempts are made to insulate the system from the tower. The outcome also shows that equipotential bonding of the grounding system, a distributed grounding network including a ring conductor and a suitable system of surge protective devices play a much vital role in lightning protection of equipment and safety of people compared to the effects of simply achieving a low grounding resistance. However, in the absence of such integrated, distributed and equipotentialized grounding system, a high value of ground resistance will sharply increase the possibility of accidents and damage. Considering the observations of the investigations into account we have designed a concrete embedded grounding system for tower sites at problematic locations. Finally, the scenarios for safety management at telecommunication tower sites have been discussed.     

An agent-based approach to explore the effect of voluntary mechanisms on land use change: A case in rural Queensland,Australia

In rural regions, land use changes (LUC) are often the result of the decision-making of individual farmers. To influence this decision-making, compulsory and voluntary mechanisms are implemented. However, farmers’ decision-making is a heterogeneous process that depends on their ability and willingness to take certain decisions. Discrepancies between farmers’ ability and willingness and the design of voluntary mechanisms occur frequently. This makes it necessary to understand how farmers’ participation in these mechanisms can affect LUC. The aim of this paper was to demonstrate an agent-based approach to analyse and explore how voluntary mechanisms can influence LUC processes in rural regions. This approach was applied to a rural region in Australia, where clearing of native vegetation has occurred for agricultural development. Historical land cover data and semi-structured interviews were used to parameterise an agent-based model. Factors that influence farmers’ ability and willingness to participate in these mechanisms were identified. Three scenarios were simulated with the model to explore how the implementation of different voluntary mechanisms can affect the landscape structure of the region. This paper identifies how the diversity of farmers’ decision-making can influence the landscape structure in the region. The advantages and limitations of an agent-based approach in relation to LUC research and policy are discussed.     

Growth conditions,elemental accumulation and induced physiological changes in Chinese cabbage

Soils contaminated with low levels of heavy metals and other trace elements are now frequently used for vegetable growing. In this situation, heavy metals and trace elements from these polluted soils may accumulate in the agricultural plants being grown in them and thereby enter the human food chain. The objectives of this study are to elucidate the effects of growth conditions, manipulated by the crop covers, on the phytoaccumulation of elements, and to investigate the conceivable influences of these conditions on the plant biochemistry. In three consecutive years of field experiments, open air (T(0)), and floating rowcover treatments (T(1): perforated polyethylene 50 micrometers; T(2): polypropylene 17 gm(-2)) were used to produce different environmental conditions for the growth of Chinese cabbage [Brassica rapa L. (Pekinensis group) cv. 'Nagaoka 50']. Five samplings (whole tops) were carried out from transplanting to harvest and measurements of B, Al, Ag, Si and Ca concentration as well as phenolics (orto-diphenols, total phenols and anthocyanins), pectic fractions, amino acids (histidine, phenylalanine and tyrosine) and polyphenol oxidase activity, were carried out in samples. The T(1) (perforated polyethylene sheet) gave greater B, Al, Ag and Si concentration and phytoextraction (in weight units) than the open-air control. These findings can help to develop new cost-effective techniques for phytoremediation as the application of plastic covers in the field. The build-up of heavy metals in those crops would make the product less suitable for human consumption.     

Relations between innovation management and organisational sustainability: a case study in a Brazilian higher education institution

Environment, Development and Sustainability - The objective of this work was to analyse the relations between innovation management and organisational sustainability in a Brazilian higher education...     

Effects of elevated yolk testosterone levels on survival, growth and immunity of male and female yellow-legged gull chicks

Androgen hormones of maternal origin contained in the eggs of avian species are considered to have positive effects on offspring characteristics and performance. However, negative consequences have also been reported, suggesting that mothers may experience a trade-off between beneficial and detrimental effects of egg androgens to offspring fitness. We studied the effects of elevated yolk testosterone (T) concentration on survival, development and phenotype of male and female yellow-legged gull (Larus michahellis) chicks by injecting egg yolks with physiological doses of the hormone. Elevated yolk T resulted in a male-biased post-hatching sex ratio, T-treated clutches producing a greater proportion of males compared to control ones at day 4 post-hatching, likely resulting from a reduction of female embryonic survival, whereas no effect of hormone treatment on hatching success or short-term chick survival was observed. In addition, T depressed post-hatching body mass in both sexes but had no effects on the intensity of the cell-mediated immune response or skeletal growth. No sex differences in egg characteristics or chick phenotype were detected. Time to hatching was not affected by T, but females originating from first laid eggs hatched earlier than males of the same laying order, independently of hormone treatment. However, the implications of sex differences in hatching times are unclear in the study species. Taken together, our results suggest that female yellow-legged gulls may be constrained in transferring androgens to their eggs by negative consequences on the viability of female offspring and growth of chicks of the two sexes.     

Female house martins (Delichon urbica) reduce egg androgen deposition in response to a challenge of their immune system

Female birds deposit in the yolks of eggs substantial amounts of androgens, such as testosterone and androstenedione. These androgens have been shown to speed up nestling development, induce a fast development of ornaments and increase dominance in adults. Experiments in several species have reported that females invest greater amounts of androgens in the eggs fathered by attractive males, suggesting that yolk androgen is a costly investment for either the offspring or the mother. There is some evidence that nestling immunocompetence may be partially suppressed by high levels of yolk androgens, but it is not known whether this is also the case for females. We tested this hypothesis in the house martin by inducing an immune challenge through an injection of sheep red blood cells, a standard challenge of the humoral immune system. Experimental birds laid eggs with lower amounts of yolk androstenedione than controls, and there was a similar non-significant trend for testosterone. Furthermore, the probability of laying a replacement clutch was higher for birds that had laid a first clutch with relatively high levels of yolk testosterone. These results suggest that yolk androgen deposition is limited by immune costs in the female, and that only females in good condition may afford to invest high levels of androgen in eggs in this species.     

Heterodonty and double occlusion in <Emphasis Type="Italic">Manidens condorensis</Emphasis>: a unique adaptation in an Early Jurassic ornithischian improving masticatory efficiency

New materials of the ornithischian dinosaur Manidens condorensis highlight a strong heterodonty between the upper and lower dentitions and reveal a novel occlusion type previously unreported in herbivorous dinosaurs. The diamond-shaped maxillary teeth have prominent cingular entolophs in a V- to Z-shaped configuration that are absent in dentary teeth. These cingular entolophs bear denticles and serrations with vertical wear that is coplanar with the apical wear facets, supporting their involvement in chewing. The separated apical and basal wear in dentary teeth is consistent with the apical and cingular wear in maxillary teeth, indicating an alternate occlusion, an orthal jaw motion, and shearing interactions between marginal and cingular edges in a double occlusion. Measurements of the length and wear area along the marginal and cingular edges indicate that the latter are functionally equivalent to adding eight teeth to a maxillary toothrow of ten, almost doubling the lengths of cutting edges and the degree of intraoral processing, while maintaining a plesiomorphic skull anatomy, an adaptation to herbivory unique in Ornithischia.     

Deferoxamine pretreatment inhibits metal neurotoxicity in Caenorhabditis elegans

Neurodegenerative diseases are increasingly common in humans. Alzheimer's disease (AD) is a neurodegenerative disease characterized by the presence of extracellular plaques containing β‐amyloid peptides and neurofibrillary tangles in the brains. Researchers have focused on the elucidation of a correlation between high concentrations of aluminum or iron (in the organism with observed neuropathology). The objective of this study was to evaluate the effects of aluminum and iron on the behavioral parameters (pharyngeal pumping and defecation cycle) of the nematode Caenorhabditis elegans pretreated with deferoxamine (DFX). Acetylcholinesterase (AChE) activity was evaluated as well. DFX is a chelant that is widely used for the treatment of metal toxicity, and it has a high affinity for aluminum and iron. The worms were pretreated with DFX, and then exposed to aluminum and iron. In the absence of DFX, aluminum exposure decreased pharyngeal pumping compared with that in the control group. The defecation cycle of the control was significantly different from that of the worms exposed to aluminum. In contrast, an increased defecation cycle was observed in worms exposed to iron without DFX pretreatment. AChE activity increased in aluminum‐exposed groups that received DFX pretreatment compared with those that did not receive pretreatment. These results suggest that pretreatment with DFX is effective in reducing metal toxicity, particularly with reference to AChE activity, which did not decrease in groups that did not receive DFX pretreatment.     

Practices of energy use management and sustainable performance in Brazilian mineral industries

Energy is an essential asset for the existence of industrial activities, however, the absence of energy use management may lead to numerous environmental, economic, and social impacts. Thus, industries, which are major consumers of energy, play an essential role in seeking to preserve the energy system. This study aimed at analyzing the practices of energy use management and their relation to sustainable performance in the industries within the Brazilian mineral sector. The practices of energy use management were measured using the model proposed by Liu et al. (2012, Journal of Cleaner Production, 26, 79–89). After that, evidence of sustainable performance was identified based on performance indicators developed by the Global Reporting Initiative (2006, 2010, 2014). The study is characterized as quantitative, and it was conducted through a survey of industries linked to the Brazilian Mining Association. Through our results, we verified that the practices related to energy use management existent in the companies that we studied are subjected to periodic verification of the impacts caused by company activities on the environment, and that attention to energy use provides an incentive to daily practices of energy saving. On the other hand, the practices of energy use management are still little disseminated among these companies, as is certification to the International Organisation for Standardization's (ISO) Energy Management Systems framework, ISO 50001. In general, through the analyses that we performed, we can verify the existence of positive associations between the factors related to the practices of energy use management and to corporate sustainable performance.     

New contributions to the study of common double mutants in the human <Emphasis Type="Italic">LDL</Emphasis> receptor gene

Variations in the gene encoding the low-density lipoprotein receptor (LDLR) can cause familial hypercholesterolemia (FH), one of the most common inherited metabolic disorders in humans. The functional effects of the p.Gln92Glu and p.Asn564His alterations are predicted as benign, but the c.313 + 1G>C and p.Lys799_Phe801del changes are believed to cause disease. Although p.Gln92Glu and c.313 + 1G>C have been observed only in Spain, p.Asn564His and p.Lys799_Phe801del are widespread in Western Europe. In order to estimate the ages (t generations) of these four variants of the gene, to determine their possible origin and to consider the influence of age and selective pressure on their spread, we analyzed 86 healthy individuals and 126 FH patients in Spain. Most of the FH patients investigated carried two of these four LDLR variants simultaneously, while only one patient carried three of them simultaneously. Haplotype analyses were based on five LDLR SNPs: c.81T>C, c.1413G>A, c.1725C>T, c.1959T>C and c.2232G>A. The results suggest that p.Gln92Glu and c.313 + 1G>C arose at about the same time (99 and 103 generations ago, respectively) in the CACTG haplotype and that p.Asn564His and p.Lys799_Phe801del appeared in the CGCCG haplotype and might be slightly more recent variations (92 and 95 generations ago, respectively). Low selective pressures could explain the maintenance of these variants in spite of their ages. The origin of p.Gln92Glu and c.313 + 1G>C appears to be in Spain whereas p.Asn564His and p.Lys799_Phe801del could have been introduced in Spain by Celtic migrations in the seventh to fifth centuries BC.