Assessing Stream Ecosystem Structure and Function in an Urban Canal and Logan River in Logan, Utah

Humans have constructed canals to support agriculture, to mitigate flooding, and to discharge stormwater, especially in the Intermountain West. These canals are common in Cache Valley, where they receive flows from the Logan River during summer months. However, the ecological structure (e.g., water quality, freshwater invertebrates) and function (e.g., leaf decomposition) of these canals remains largely unknown. Studying ecosystem structure and function of these urban waterways is important because it can inform us of the health of these waterways. My research had three objectives. First, I compared water chemistry, invertebrate assemblages, and leaf decomposition in an urban canal and the Logan River in Logan, Utah. Next, I compared these variables along a longitudinal urban gradient (i.e., from upstream reaches to downstream reaches of the waterways). Last, I examined which of the various environmental factors I measured was correlated with shredders (i.e., leafshredding invertebrates) and leaf decomposition in both waterways. Water quality was similar between the Logan River and the canal, except for the most downstream site of the Logan River which had a higher concentration of nutrients and heavy metals. The canal had faster leaf decomposition, and facultative shredders were abundant in the canal. Facultative shredders increased with the decay rate in the canal, suggesting that these shredders are playing a critical role aiding in leaf decomposition in the canal. The most downstream sites in the canal may have had faster leaf decomposition due to facultative shredders whereas the most downstream sites in the Logan River may have had faster decomposition because of elevated concentrations of nutrients. I found that physical forces from the flow of streams (e.g., water velocity) and shredder biomass were correlated with leaf decomposition in both waterways. Total phosphorus was also correlated with shredder biomass and leaf decomposition, the latter of which is likely due to enhanced microbial activity on leaf litter

Issue Brief: Minority Religion and Violence

The following issue brief is meant to address the relationship between minority religious groups living in America and violence. This topic will be addressed through an analysis of minority religion groups committing violent acts and minority religion groups facing violence committed by others. The brief will focus on why violent attacks happen by and against minority religion groups, and will cite the Muslim and Jewish populations in America for more specific examples

Characterization of growth and antibiotic resistance in Burkholderia cepacia complex organisms

Introduction: Isolates are opportunistic pathogens within the Burkholderia cepacia Complex (Bcc). One key characteristic is that they are gram-negative, thereby making them generally resistant to hydrophobic molecules.Hypothesis: Exclusionary properties of the gram-negative outer membrane for hydrophobic substances are at least partially responsible in cases where clinical isolates of Bcc species are intrinsically resistant to hydrophobic antibacterial agents.Study Design: This hypothesis will be tested using turbidimetric growth and disk agar diffusion and bioassays.Methods: Test samples were cultivated in a shaking incubator for six hours at 180 rpm and 37 degrees Celsius to determine their respective growth rates. Spectrophotometric readings were taken every half hour to measure optical density at 620 nm wavelength. Test samples were also grown to 0.1 optical density and then streaked onto a Petri dish containing Mueller Hinton agar. Eight different antibiotic discs were dispensed onto the seeded agar surfaces and compounds were allowed to diffuse at three degrees Celsius for one hour, and then samples were incubated for 24 hours at 37 degree Celsius.Results: All Bcc isolates exhibited similar sigmoid growth curves and yielded similar amounts of biomass. Overall, they were slightly susceptible to triclosan and rifampin, and moderately to very susceptible to clindamycin and novobiocin.Conclusion: The Bcc isolates were pure cultures and exhibited similar in vitro growth characteristics. Their similar patterns of resistance and susceptibility to hydrophobic antibacterial agents suggests phenotypic outer membrane exclusion properties for hydrophobic molecules is largely conserved among the Burkholderia species examined

An exploration into the influence of schizotypic maternal personality on early sensory development

It has been known for some time that maternal personality is an influential factor in determining developmental and clinical outcomes in childhood risk for mental health. Current literature describes schizotypy as a multidimensional construct, representing a vulnerability to the schizophrenia-spectrum. This thesis investigates atypicalities observed throughout the spectrum aiming to determine whether these were present in mothers with sub-clinical schizotypy, and their offspring. Chapter 2 explored sensory gating in infants at 6-months of age. Infants displayed intact sensory gating, and there was no difference between infants of schizotypic and those of control mothers. The mothers of the infants displayed significant differences between Stimulus 1 and Stimulus 2, but also differences as a result of their schizotypy dimensionality; replicating prior literature. Similarly, in Chapter 3, schizotypic mothers displayed reduced oscillatory power towards Stimulus 1 of the paired-tone paradigm, replicating prior literature. In contrast, their infants showed no group differences. This implies that having a mother with schizotypic traits does not influence the sensory gating ability of their 6-month-old infants. Chapter 4 demonstrated that 6-month-old infants differentiated between happy and fearful emotional facial expressions, replicating prior literature. Maternal schizotypy, however, did not influence this ability. When exploring face processing in the maternal sample, schizotypic mothers exhibited greater amplitudes towards both facial expressions when contrasted with non-schizotypic mothers. In Chapter 5 we explored relationships between schizotypy and mother-child interactions in a free play session. We found that oscillatory power shown by infants in their left and right parietal regions was greater when their mother was talking to them, or when they were playing independently with a toy, compared to a baseline. No significant differences were observed between infants of schizotypic, and those of control mothers. Despite a lack of infant group effects, it is important to explore schizotypal expression during adolescence and adulthood as a critical link to childhood risk markers, which confer a role of developmental facilitators on the road to psychosis proneness. This thesis concludes that schizotypy is linked to the schizophrenia-spectrum, as shown consistently by maternal electrophysiological data, but that maternal level of schizotypy did not have an effect on infant markers

Interactions between native and exotic plants in the context of grassland restoration and the importance of below-ground processes

The importance of native ecosystems is being ever more realised as human-induced environmental change leads to ecosystem degradation. This is spurring increased efforts to restore ecosystems. In previously cultivated landscapes (old-fields) the legacy of farming practices can persist for decades and present many challenges for restoration. This thesis is focussed on identifying and overcoming some of these challenges that limit restoration efforts. The overall aims were to develop a mechanistic understanding of the processes hindering native grass establishment and to improve the effectiveness of techniques used in the restoration of native grasslands. Two glasshouse experiments (chapters 2 and 3) were designed to investigate whether soil microbial communities present in old-fields hinder native plant establishment and allow exotic plants to dominate. The results indicate that native grasses performed better in the presence of soil microbes from remnant grassland. However, these microbial effects were heavily influenced by nutrient availability in the soil. Characterisation of the microbial communities, using molecular barcoding, revealed that they differed between old-field sites and remnant grassland. Differences in soil physiochemical properties between soil types, as well as the presence of different plant species, appear to explain the observed differences in microbial community composition. In turn, these changes in microbial communities affected plant performance, particularly when soil nutrient availability was low. High nutrient availability in old-fields from past farming practices usually results in dominance of fast-growing annual exotic plants. Reducing soil fertility is therefore seen as an effective approach to restoration. I trialled four methods (carbon supplements, slashing, burning, and scalping; chapter 4) to 1) reduce biomass of exotic species, 2) reduce soil nutrients, and 3) increase biomass of native grasses. Overall, scalping was the only method to achieve all three aims whereas carbon supplements and slashing reduced exotic biomass with no apparent benefit to native species. Both carbon supplements and scalping resulted in changes to the soil microbial community. Given the importance of plant-soil interactions, the implications of these result for future restoration works are discussed. One strategy to promote resistance to invasion in a revegetated community is to plant species that use resources in a complementary way, i.e. planting a diversity of functional groups. In a field trial (chapter 5), grass species from complementary functional groups (chosen based on phenology) were grown in different combinations and densities to test whether native communities are more resistant to invasion if resources are utilised all year round (niche saturation). Overall, high density planting was most effective at lowering exotic biomass. Planting C3 (winter-growing) and C4 (summer-growing) grasses together did not reduce invasibility, in contrast to my predictions. Instead, planting C3 plants alone was effective at reducing exotic biomass, providing evidence that planting functional groups that match the functional group of potential invaders could be an effective strategy for restoration. Findings presented in this thesis demonstrate the importance of soil amendments, both abiotic and biotic, and planting arrangements in ecological restoration. Greater consideration of these should lead to more successful and sustainable restoration outcomes in grassland habitats.Thesis (Ph.D.) -- University of Adelaide, School of Biological Sciences, 201

The effect of dietary intake, physical activity and posture on pepsin concentrations detected in the saliva of free-living, healthy individuals

Introduction: Diet and lifestyle are believed to be major causes of gastric reflux. The occurrence of reflux is associated with a number of respiratory, oesophageal and airways conditions. Previous studies have used oesophageal monitoring to assess the occurrence of reflux events. Such measurements may only measure "bulk" rather than "microreflux" events. Such technology is also likely to impact on both habitual dietary intake and physical activity due to the nature of the assessment. Aim: To assess the impact of meal intake and physical activity on pepsin concentrations in saliva collected from free-living individuals throughout the day. Methods: Fifty-one participants (aged 18+, non-smokers with no current chronic or acute respiratory conditions, bloodborne diseases, or diagnosis of reflux disease) provided saliva samples before (< 30 min) and after (< 1 h) meals and physical activity bouts or before and after sleep. Dietary intake and physical activity were monitored by diary over this time. Dietary intake was analyzed using Windiets® software, while physical activity output was calculated from pre-existing tables of energy expenditure. Saliva samples were analyzed for pepsin content using a previously described ELISA methodology. Wilcoxon matched pairs rank sign tests were performed on before- and after-meal/physical activity/sleep samples. Results: Fifty-seven paired pre-and post-meal,48 paired pre- and post-physical activity samples and 168 pre- and post-sleep samples were analyzed. Mean(standard deviation) pepsin concentrations in saliva were significantly higher (P=0.037) in the pre-meal samples (44.2(42.2)) than the post-meal samples (32.8(29.6)). Post-sleep pepsin concentrations (196.4(323.4)) were significantly higher (P< 0.001) than pre-sleep (102.3(152.8)). There was no significant difference (P=0.491) between pre-(45.2(56.8)) and post-(40.8(38.6)) physical activity saliva samples. Conclusions: Analysis of pepsin in saliva is a useful method to assess the impact of lifestyle on reflux event occurrence. Increased preprandial salivary pepsin concentrations may be due to microreflux events driven by the cephalic phase of digestion

Underground mining of aggregates. Main report

This report examines the economic feasibility of underground mining for crushed rock aggregates in the UK, but particularly in the London, South East and East of England regions (the South East area of England). These regions import substantial volumes of crushed rock, primarily from the East Midlands and South West regions, requiring relatively long transport distances to market for this bulk commodity. A key part of the research was to determine whether or not aggregate could be produced and delivered to a local market from an underground aggregates operation at a cost comparable with that for production and transport of the commodity from traditional surface quarries located further afield. In essence the investigation asked – could the reduced transport costs compensate for the higher production costs underground so that underground crushed rock aggregates producers can compete with the established Leicestershire and Somerset surface quarries exporting to the South East? Work Programme The research effort involved establishing and verifying cost models for aggregates production, stone processing (sizing and sorting), haulage of product to market, environmental impact mitigation, health and safety, decommissioning and restoration. Another major element of the work was the re-examination of the BGS exploratory borehole and geophysical databases to identify potential areas of crushed rock aggregates resource at depth in the South East area of England. Land use pressure is typically higher in this area of England than elsewhere so another major part of the research was the identification of potential concurrent uses of land around the surface facilities of underground aggregates mines. The value, development costs for specific developments and determination of yields expected, from these uses were estimated. These were also used to investigate potential economic benefits associated with after uses of remediated surface land above potential underground aggregates mines and also for the new underground space that would be created. Key technical issues such as subsidence within relatively heavily populated areas of the South East area of England were also addressed. Economic Results The discounted cost of aggregate delivered at a discount rate of 10% was the metric used to appraise the options. This is the price of aggregate that leads to a zero net present value of project cash flows realised over the aggregates project life. The results show that the discounted costs of aggregate delivered to a local South East area of England market from an underground mine producing 3.5 million tonnes per annum (MTPA) of crushed rock aggregates, are in the range of £13.03 per tonne to £13.93 per tonne for the top six prospect locations. These are greater than the corresponding cost for a “reference” quarry in Leicestershire producing 3.5 MTPA (£10.95 per tonne), but lower than a “reference” quarry in Leicestershire producing 1.25 MTPA (£16.48 per tonne). These figures indicate that underground crushed rock aggregate mines located within the South East area of England may be able to compete for a share in the overall market by replacing / displacing aggregate imported from the quarries in Leicestershire and Somerset producing around or less than 1.25 MTPA. The surprise in these figures is not really that the more remote surface quarry has a lower discounted cost of aggregate delivered, but that the values for the quarry and underground mine are so close. The capital intensity for the development of underground aggregates mines was found to be higher than that required for surface quarries of comparable scale, by a factor ranging from 1.33 to 1.65 and thus may represent a disincentive for aggregates operators. Carbon Emissions The total carbon emissions of the ‘reference’ 3.5 MTPA quarry in Leicestershire were estimated at 9.28 kg CO2/tonne aggregate delivered and this is to be compared with carbon emissions for the 150 metre deep underground mines serving the local market which were estimated at 9.31 kg CO2/tonne delivered for a Bletchley prospect using an adit to access the sub-surface and 14.25 kg CO2/tonne delivered for a prospect based on the Chitty bore hole using a shaft. Depth of the mine is a key factor in determination of the relative carbon emissions from each of the underground mining operations considered as electricity consumption for ventilation, pumping and winding is proportional to depth. Recommendations The current research generated seven principal recommendations which are discussed in detail in the concluding section of the report. These are: Appraise policy incentives for underground aggregates mining. Conduct an industry-wide consultation on findings from the current research. Obtain public and stakeholder opinion on new uses for underground space. Conduct research to reducing the energy intensity of mine services. Develop a deep level aggregates-specific drilling campaign. Investigate underground aggregates mines developed from existing surface quarries. Investigate underground aggregates as co-products of industrial minerals mining

EpiJSON: A unified data-format for epidemiology

AbstractEpidemiology relies on data but the divergent ways data are recorded and transferred, both within and between outbreaks, and the expanding range of data-types are creating an increasingly complex problem for the discipline. There is a need for a consistent, interpretable and precise way to transfer data while maintaining its fidelity. We introduce ‘EpiJSON’, a new, flexible, and standards-compliant format for the interchange of epidemiological data using JavaScript Object Notation. This format is designed to enable the widest range of epidemiological data to be unambiguously held and transferred between people, software and institutions. In this paper, we provide a full description of the format and a discussion of the design decisions made. We introduce a schema enabling automatic checks of the validity of data stored as EpiJSON, which can serve as a basis for the development of additional tools. In addition, we also present the R package ‘repijson’ which provides conversion tools between this format, line-list data and pre-existing analysis tools. An example is given to illustrate how EpiJSON can be used to store line list data. EpiJSON, designed around modern standards for interchange of information on the internet, is simple to implement, read and check. As such, it provides an ideal new standard for epidemiological, and other, data transfer to the fast-growing open-source platform for the analysis of disease outbreaks

The influence of Schizotypy on Event Related Oscillations in Sensory Gating during early Infant Development

Maternal personality is known to influence childhood risk factors for mental health. More specifically, maternal psychopathologies, such as those on the schizophrenia-spectrum have been associated with P50 sensory gating abilities. Schizotypy is a personality dimension within the general population elevated among schizophrenia-spectrum patients and their first-degree relatives. Sensory gating is the pre-attentional habituation of responses distinguishing between important and irrelevant information. Neurooscillatory deficits have been observed in this ability in individuals diagnosed with schizophrenia. The current study investigated whether mothers with schizotypy (n=33) and their 6-month-old infants (n=38) display reduced evoked-oscillatory activity. The mothers completed the Oxford-Liverpool Inventory of Feelings and Experiences – Short Form as an index of schizotypy dimensionality, which was used to categorise the participants into infants of control mothers and mothers with schizotypy. The paired-tone paradigm: two identical auditory tones (Stimulus 1 and Stimulus 2) played 500ms apart, were used to probe evoked oscillatory activity. Data revealed that although the infants’ evoked-oscillations displayed differences between Stimulus 1 and Stimulus 2, there were no group differences between infants of mothers with schizotypy and of control mothers. Their mothers, however, displayed differences, with reduced power toward Stimulus 1 observed in the mothers with schizotypy between 13-30Hz. These findings are consistent that early sensory processes, such as sensory gating are impaired in schizophrenia-spectrum disorders

Eye gaze and Ageing:Selective and combined effects of working memory and inhibitory control

Eye-tracking is increasingly studied as a cognitive and biological marker for the early signs of neuropsychological and psychiatric disorders. However, in order to make further progress a more comprehensive understanding of the age-related effects on eye-tracking is essential. The antisaccade task requires participants to make saccadic eye movements away from a prepotent stimulus. Speculation on the cause of the observed age-related differences in the antisaccade task largely centres around two sources of cognitive dysfunction: inhibitory control and working memory. The inhibitory control account views cognitive slowing and task errors as a direct result of the decline of inhibitory cognitive mechanisms. An alternative theory considers that a deterioration of working memory is the cause of these age-related effects on behaviour. The current study assessed inhibitory control and working memory processes underpinning saccadic eye movements in young and older participants. This was achieved with three experimental conditions that systematically varied the extent to which working memory and inhibitory control were taxed in the antisaccade task; a memory-guided task was used to explore the effect of increasing the working memory load; a Go/No-go task was used to explore the effect of increasing the inhibitory load; a ‘standard’ antisaccade task retained the standard working memory and inhibitory loads. Saccadic eye movements were also examined in control condition: the standard prosaccade task where the load or working memory and inhibitory control was minimal or absent. Saccade latencies, error rates and the spatial accuracy of saccades of older participants were compared to the same measures in healthy young controls across the conditions. The results revealed that ageing is associated with changes in both inhibitory control and working memory. Increasing the inhibitory load was associated with increased reaction times in the older group, whilst the increased working memory load and the inhibitory load contributed to an increase in the anti-saccade errors. These results reveal that ageing is associated with changes in both inhibitory control and working memory