Repair and Strengthening of Bridge Substructures

Deterioration of bridge substructures has been a serious concern throughout Wisconsin. Concrete, steel and timber members all require distinct repair methods which not only address the true causes of deterioration, but protect the member from future damage. Utilizing repair techniques that merely address the effect of the deterioration has proven costly and unreliable. Understanding the relationship between cost and service life of modern repair methods can help maintenance engineers make informed decisions that will maximize efficacy. A survey was sent to 90 maintenance engineers throughout the United States to determine the efficacy and cost of common repair methods. Unique repair procedures were also investigated based on the results of the survey. Eight bridges throughout the Southeast and Southwest regions of WisDOT were documented. These bridges displayed varying stages of deterioration as well as typical repair methods. By evaluating these bridges it was determined that the damage caused by deicing chemicals is extensive and varying. Expansion joint degradation has accounted for a large portion of deterioration throughout Wisconsin’s bridge infrastructure. Documentation indicating how long repairs had been in place gave the research team an estimate for longevity of repairs in Wisconsin. Repair methods were documented and analyzed for concrete, timber, steel and scour. They were considered for their longevity, relevance in Wisconsin’s climate, ease of completion and cost. Further organization highlighted repairs based on specific substructure element relevance, in an attempt to address unique deterioration by substructure member. After the repairs were analyzed, three separate decision matrices were created in order to compare differing repair methods. Decision matrices were created for concrete repairs, pile repairs and scour repairs. The pile repair decision matrix was created in lieu of separate timber and steel decision matrices, since those materials are typically only used for piles of modern substructures. These decision matrices can be used to design appropriate substructure repairs which will be both cost-effective and durable

Lateral entorhinal cortex lesions impair local spatial frameworks

A prominent theory in the neurobiology of memory processing is that episodic memory is supported by contextually gated spatial representations in the hippocampus formed by combining spatial information from medial entorhinal cortex (MEC) with non-spatial information from lateral entorhinal cortex (LEC). However, there is a growing body of evidence from lesion and single-unit recording studies in rodents suggesting that LEC might have a role in encoding space, particularly the current and previous locations of objects within the local environment. Landmarks, both local and global, have been shown to control the spatial representations hypothesised to underlie cognitive maps. Consequently, it has recently been suggested that information processing within this network might be organized with reference to spatial scale with LEC and MEC providing information about local and global spatial frameworks respectively. In the present study, we trained animals to search for food using either a local or global spatial framework. Animals were re-tested on both tasks after receiving excitotoxic lesions of either the MEC or LEC. LEC lesioned animals were impaired in their ability to learn a local spatial framework task. LEC lesioned animals were also impaired on an object recognition task involving multiple local features but unimpaired at recognizing a single familiar object. Together, this suggests that LEC is involved in associating features of the local environment. However, neither LEC nor MEC lesions impaired performance on the global spatial framework task.Publisher PDFPeer reviewe

Increased flexibility of CA3 memory representations following environmental enrichment

This work was supported by a grant from the BBSRC (BB/X007197/1).Peer reviewe

Diesel has to go:Making the case for gas and biogas engines

This study explores the commercialization process of small to medium enterprises (SME’s), using the case study method to delve into the unique experiences of one firm who are currently in the process of commercialising their innovative low emission engine solutions. The study reviews the existing literature, exploring the challenges associated with commercialization, focusing on the specific challenges of commercialising high technologies into the market, and how the firm can aim to address the market’s needs and preferences. The gaps in the literature include a lack of knowledge on how SME’s can use their network during the commercialization process. The principal theories used to underpin this study include Teece’s Technological Commercialization Theory (Teece, Pisano , & Shuen, 1997), and the Network Theory (Ford & Mouzas, 2010). The SME is then situated within the context of industry, and the markets of interest are outlined, specifically the small power generation markets in Sub-Saharan Africa, India, and the United Kingdom. The study uses semi-structured interviews to gain qualitative data on the experiences of those in industry and within the SME. Through thematic analysis, the data was coded, and themes emerged. The analysis revealed a strong market need from the industry for low emission solutions to reduce carbon emissions, and a willingness to adopt high technologies, whilst also outlining the potential roadblocks of new innovations entering the market. The analysis from the participants within the SME indicate strong expertise in technological capabilities to meet the market need, whilst the challenges facing the SME surrounded financial resources and strategic direction. The study concludes by addressing the gaps in the literature through discussion of how the SME can navigate its associated challenges and access the market through its network

Accounting and corruption: a cross‐country analysis

Purpose – The purpose of this paper is to better understand the relationship between accounting and auditing quality and the perceived level of corruption. Design/methodology/approach – This relationship is studied by performing a cross-country analysis using public data to measure accounting quality, audit quality, and corruption. Findings – Consistent with our predictions, we find evidence that accounting and auditing quality are significantly related to the level of perceived corruption in a country. Research Limitations/implications –These findings suggest that countries with more transparent reporting have lower levels of perceived corruption and that the level of perceived corruption may be reduced in a country by improving accounting and auditing quality. Practical implications – The findings suggest that countries can reduce the level of perceived corruption by improving the transparency of financial reporting by improving accounting and auditing standards. Originality/value – While significant amounts of research has examined perceived corruption, this study is the first to address the impact of high quality accounting information on the level of perceived corruption. Keywords Corporate Governance, Comparative Accounting Systems and Practice, Auditing, International Regulations, Corruption, Business/Government interaction and relations; Paper Type Research Pape

Disambiguating past events: accurate source memory for time and context depends on different retrieval processes

Participant payment was provided by the School of Psychology and Neuroscience ResPay scheme.Current animal models of episodic memory are usually based on demonstrating integrated memory for what happened, where it happened, and when an event took place. These models aim to capture the testable features of the definition of human episodic memory which stresses the temporal component of the memory as a unique piece of source information that allows us to disambiguate one memory from another. Recently though, it has been suggested that a more accurate model of human episodic memory would include contextual rather than temporal source information, as humans’ memory for time is relatively poor. Here, two experiments were carried out investigating human memory for temporal and contextual source information, along with the underlying dual process retrieval processes, using an immersive virtual environment paired with a ‘Remember-Know’ memory task. Experiment 1 (n = 28) showed that contextual information could only be retrieved accurately using recollection, while temporal information could be retrieved using either recollection or familiarity. Experiment 2 (n = 24), which used a more difficult task, resulting in reduced item recognition rates and therefore less potential for contamination by ceiling effects, replicated the pattern of results from Experiment 1. Dual process theory predicts that it should only be possible to retrieve source context from an event using recollection, and our results are consistent with this prediction. That temporal information can be retrieved using familiarity alone suggests that it may be incorrect to view temporal context as analogous to other typically used source contexts. This latter finding supports the alternative proposal that time since presentation may simply be reflected in the strength of memory trace at retrieval – a measure ideally suited to trace strength interrogation using familiarity, as is typically conceptualised within the dual process framework.PostprintPeer reviewe

Hippocampal CA1 place cells encode intended destination on a maze with multiple choice points

The hippocampus encodes both spatial and nonspatial aspects of a rat's ongoing behavior at the single-cell level. In this study, we examined the encoding of intended destination by hippocampal (CA1) place cells during performance of a serial reversal task on a double Y-maze. On the maze, rats had to make two choices to access one of four possible goal locations, two of which contained reward. Reward locations were kept constant within blocks of 10 trials but changed between blocks, and the session of each day comprised three or more trial blocks. A disproportionate number of place fields were observed in the start box and beginning stem of the maze, relative to other locations on the maze. Forty-six percent of these place fields had different firing rates on journeys to different goal boxes. Another group of cells had place fields before the second choice point, and, of these, 44% differentiated between journeys to specific goal boxes. In a second experiment, we observed that rats with hippocampal damage made significantly more errors than control rats on the Y-maze when reward locations were reversed. Together, these results suggest that, at the start of the maze, the hippocampus encodes both current location and the intended destination of the rat, and this encoding is necessary for the flexible response to changes in reinforcement contingencies

Lateral entorhinal cortex lesions impair both egocentric and allocentric object-place associations

This work was supported by Biotechnology and Biological Sciences Research Council (BBSRC) grant BB/I019367/1.During navigation, landmark processing is critical either for generating an allocentric-based cognitive map or in facilitating egocentric-based strategies. Increasing evidence from manipulation and single-unit recording studies has highlighted the role of the entorhinal cortex in processing landmarks. In particular, the lateral (LEC) and medial (MEC) sub-regions of the entorhinal cortex have been shown to attend to proximal and distal landmarks, respectively. Recent studies have identified a further dissociation in cue processing between the LEC and MEC based on spatial frames of reference. Neurons in the LEC preferentially encode egocentric cues while those in the MEC encode allocentric cues. In this study, we assessed the impact of disrupting the LEC on landmark-based spatial memory in both egocentric and allocentric reference frames. Animals that received excitotoxic lesions of the LEC were significantly impaired, relative to controls, on both egocentric and allocentric versions of an object–place association task. Notably, LEC lesioned animals performed at chance on the egocentric version but above chance on the allocentric version. There was no significant difference in performance between the two groups on an object recognition and spatial T-maze task. Taken together, these results indicate that the LEC plays a role in feature integration more broadly and in specifically processing spatial information within an egocentric reference frame.Publisher PDFPeer reviewe

Distance- rather than location-based temporal judgements are more accurate during episodic recall in a real-world task

Definitions of episodic memory typically emphasise the importance of spatiotemporal frameworks in the contextual reconstruction of episodic retrieval. However, our ability to retrieve specific temporal contexts of experienced episodes is poor. This has bearing on the prominence of temporal context in the definition and evaluation of episodic memory, particularly among non-human animals. Studies demonstrating that rats rely on elapsed time (distance) rather than specific timestamps (location) to disambiguate events have been used to suggest that human episodic memory is qualitatively different to other species. We examined whether humans were more accurate using a distance- or location-based method for judging when an event happened. Participants (n = 57) were exposed to a series of events and then asked either when (e.g., 1:03 pm) or how long ago (HLA; e.g., 33 min) a specific event took place. HLA judgements were significantly more accurate, particularly for the most recently experienced episode. Additionally, a significantly higher proportion of participants making HLA judgements accurately recalled non-temporal episodic features across all episodes. Finally, for participants given the choice of methods for making temporal judgements, a significantly higher proportion chose to use HLA judgements. These findings suggest that human and non-human temporal judgements are not qualitatively different.PostprintPeer reviewe

The discrimination ratio derived from Novel Object Recognition tasks as a measure of recognition memory sensitivity, not bias

Translational recognition memory research makes frequent use of the Novel Object Recognition (NOR) paradigm in which animals are simultaneously presented with one new and one old object. The preferential exploration of the new as compared to the old object produces a metric, the Discrimination Ratio (DR), assumed to represent recognition memory sensitivity. Human recognition memory studies typically assess performance using signal detection theory derived measures; sensitivity (d′) and bias (c). How DR relates to d′ and c and whether they measure the same underlying cognitive mechanism is, however, unknown. We investigated the correspondence between DR (eye-tracking-determined), d′ and c in a sample of 37 humans. We used dwell times during a visual paired comparison task (analogous to the NOR) to determine DR, and a separate single item recognition task to derive estimates of response sensitivity and bias. DR was found to be significantly positively correlated to sensitivity but not bias. Our findings confirm that DR corresponds to d′, the primary measure of recognition memory sensitivity in humans, and appears not to reflect bias. These findings are the first of their kind to suggest that animal researchers should be confident in interpreting the DR as an analogue of recognition memory sensitivity