Investigating Uranium incorporation in modern carbonates by sequential extraction: Applied to the Permian - Triassic boundary in Lung Cam, Vietnam

The Uranium (U) isotopic system can be used to model the extent of global-scale ocean anoxia by utilizing the 238U/235U ratios as a paleo-redox indicator (δ238U). While recent studies have shown promise with the use of this novel proxy, variability is seen in modern carbonate sediment samples suggesting that more work is needed in order to understand elemental U uptake during early marine diagenesis. This thesis utilizes a sequential extraction methodology in order to understand the distribution of authigenic U within carbonate sediments. This thesis consists of four parts, (1) an evaluation and modification of a sequential extraction methodology for U uptake in modern carbonate sediments, (2) application of the modified sequential extraction method to the study U distribution within chemical fractions within Bahamian bulk sediments, (3) the application of the modified methodology to study the U distribution across the Permian–Triassic boundary from the Lung Cam section in Northern Vietnam, and (4) the implications of authigenic U toward the δ238U paleo-redox marker. Results show that a sequential extraction can be successful within carbonate sediments. The results of this sequential extraction shows that the majority of authigenic U is found within the exchangeable and carbonate fraction. This thesis hypothesizes that this U component is a non-crystalline U(IV) species. Furthermore, this authigenic U component was also found within the Permian–Triassic section located in Lung Cam, Vietnam, thus illustrating preservation of heavy authigenic U within the rock record

On the Road Again: The D.C. Circuit Reinvigorates the Work-Product Doctrine in United States v. Deloitte & Touche

The article discusses the court case United States v. Deloitte & Touch, where in the current status of the work-product doctrine that has been applied to audit workpapers are provided. It informs about the decision taken by the U.S. Court of Appeals for District of Columbia corresponding to the policy and legal arguments for and against the discoverability of audit workpapers. It also provides a sound legal framework for understanding case law and statute

A Method for Incorporating Negative Data into Rule Induction

Negative data is defined by observations of unsuccessful events or poor performance. Traditional wisdom dictates that negative data be eliminated from training data sets. This paper presents a three step method for incorporating negative data into the rule induction process. The first step is to deploy rule induction using a data set containing only positive data. This is traditionally how rule induction techniques such as ID3, C4.5 and CART are used. The second step is to create a training data set that contains all of the positive data from Step 1 and also incorporates negative data. The dependent variable from Step 1 becomes a dependent variable in the new data set, and a new performance-related independent variable is defined. Decision rules are generated using the same rule induction algorithm used in Step 1. The third and final step is to reconcile the two rule sets. A step-wise procedure for creating a final, robust rule set is proposed. An example application, related to Just-In-Time manufacturing, is presented in which decision rules are generated using the classification and regression tree (CART) technique

Open-Set Graph Anomaly Detection via Normal Structure Regularisation

This paper considers an under-explored Graph Anomaly Detection (GAD) task, namely open-set GAD, which aims to detect anomalous nodes using a small number of labelled training normal and anomaly nodes (known as seen anomalies) that cannot illustrate all possible inference-time abnormalities. The task has attracted growing attention due to the availability of anomaly prior knowledge from the label information that can help to substantially reduce detection errors. However, current methods tend to over-emphasise fitting the seen anomalies, leading to a weak generalisation ability to detect unseen anomalies, i.e., those that are not illustrated by the labelled anomaly nodes. Further, they were introduced to handle Euclidean data, failing to effectively capture important non-Euclidean features for GAD. In this work, we propose a novel open-set GAD approach, namely normal structure regularisation (NSReg), to leverage the rich normal graph structure embedded in the labelled nodes to tackle the aforementioned two issues. In particular, NSReg trains an anomaly-discriminative supervised graph anomaly detector, with a plug-and-play regularisation term to enforce compact, semantically-rich representations of normal nodes. To this end, the regularisation is designed to differentiate various types of normal nodes, including labelled normal nodes that are connected in their local neighbourhood, and those that are not connected. By doing so, it helps incorporate strong normality into the supervised anomaly detector learning, mitigating their overfitting to the seen anomalies. Extensive empirical results on real-world datasets demonstrate the superiority of our proposed NSReg for open-set GAD

The acquisition of novel word meanings from recreational reading under massed and distributed learning conditions

Children learning English as a second language acquire much vocabulary from recreational reading (RR) as do their English native-speaking peers. Such learning typically involves a cycle of repeated encounters with the same novel word in different contextual settings, each encounter serving to consolidate and build upon prior knowledge (Nation, 1990). This dissertation examines one factor that potentially impacts upon the pedagogical value of RR as a vocabulary-building practice: the time intervals between the reader‘s encounters with the same novel word while engaged in in-class RR sessions. The study employs five sets of texts, each designed to expose the reader to a uniquely more, or less, distributed encounter with a small sample of non-words particular to the set in which they occur. Employing a researcher-designed data-elicitation instrument (the Vocabulary State Assignment Task (VSAT)), the study demonstrates that among a population of Thai primary school English as a second language (ESL) children, distributed encounters with novel non-words potentially lead to more impressive meaning gains of those same non-words than do massed encounters (i.e., many encounters with the same word over a relatively short time period). Drawing upon three alternative (reasonable) notions of word knowing, the investigation demonstrates that each is associated with different learning outcomes in terms of (a) whether total word gains from reading any one set of texts differed significantly from those associated with reading another and (b) how substantial were gains attributable to more or less distributed word presentations. A breakdown of target word gains by syntactic class (nouns, verbs, adjectives, and adverbs) revealed an association between how distributed were occurrences of the same novel word and statistically significant differences in the proportions of learned words of the class of interest. The study concludes that spaced learning impacts more upon gains of nouns and verbs than it does adjectives and adverbs. Whether differences in noun and/or verb totals proved significantly different depended upon the definition of known word one acknowledges

Visualisation of latent fingerprint on wild bird eggshells by alternate light sources following superglue fuming

The theft of the eggs of endangered or protected species of bird, and subsequent reduction in wildlife population, is a significant problem worldwide. Detection rates are comparatively low towards this type of crime and fingerprinting of egg shells is infrequently utilised due to the technical barrier. This paper explores a novel technique using cyanoacrylate (superglue) fuming in conjunction with fluorescent dye to visualise latent fingerprints upon avian eggshells assisted with alternate light sources. A systematic investigation of experimental parameters has also been carried out to optimise the condition for the fingerprint visualisation. This research project has successfully developed latent fingerprints upon smooth wild bird eggshells but was less successful on developing prints on more textured, porous eggshells.Published onlin

Changing the conversation about prostate cancer among African Americans: results of formative research

Objectives: To understand obstacles to and opportunities for improving prostate cancer communication to and within African American communities. Design: Researchers conducted interviews with 19 community leaders and five focus groups with healthy men and survivors. The team also conducted process evaluations of two outreach projects in which survivors spoke to African American men about prostate cancer and screening. Results: Three levels of obstacles to prostate cancer screening and treatment were identified. Individual-level obstacles included limited knowledge about the condition, about prevention and treatment, and fear of cancer. Socio-cultural barriers included distrust of the medical system, lack of a provider for routine and preventive care, reluctance to talk about cancer, and aversion to aspects of screening. Institutional deficits included the scarcity of educational efforts targeting prostate cancer. Outreach project evaluations suggested that survivors can be effective in building prostate cancer knowledge, promoting positive attitudes toward screening, and fostering conversations about prostate cancer. Educational efforts included little information about screening risks and decision-making however. Conclusions: The findings suggest that most potent interventions may combine survivor-led education with mass media and institution-based outreach. Such comprehensive programs could shift social norms that inhibit conversation and foster fear, leading in turn to more informed decisions and better treatment outcomes

Redox conditions, glacio-eustasy, and the status of the Cenomanian–Turonian Anoxic Event: new evidence from the Upper Cretaceous Chalk of England

The nature of the Cenomanian–Turonian Oceanic Anoxic Event (CTOAE) and its δ13 C Excursion is considered in the light of (1) the stratigraphical framework in which the CTOAE developed in the European shelf seas, (2) conclusions that can be drawn from new detailed investigations of the Chalk succession at three locations in England, at Melton Ross and Flixton in the Northern Province where organic-rich ‘black bands’ are present, and at Dover in the Southern Province (part of the Anglo-Paris Basin) where they are absent, and (3) how these conclusion fit in with the present understanding of the CTOAE. The application of the cerium anomaly method (German and Elderfield 1990) at Dover, Melton Ross and Flixton has allowed the varying palaeoredox conditions in the Chalk Sea and its sediments to be related to the acid insoluble residues, organic carbon, δ18O (calcite), δ13C (calcite), δ13C (organic matter), Fe 2+ and Mn2+ (calcite), and P/TiO2 (acid insoluble residue). This has provided evidence that the initial stages of the δ13C Excursion in England were related to (1) a drop of sea level estimated at between 45 and 85 metres, (2) influxes of terrestrial silicate and organic detritus from adjacent continental sources and the reworking of exposed marine sediments, and (3) the presence of three cold water phases (named the Wood, Jefferies and Black) associated with the appearance of the cold-water pulse fauna during the Plenus Cold Event. Conditions in the water column and in the chalk sediment were different in the two areas. In the Northern Province, cerium-enriched waters and anoxic conditions were widespread; the δ13C pattern reflects the interplay between the development of anoxia in the water column and the preservation of terrestrial and marine organic matter in the black bands; here the CTOAE was short-lived (~0.25 Ma) lasting only the length of the Upper Cenomanian Metoicoceras geslinianum Zone. In the Southern Province, water conditions were oxic and the δ13C Excursion lasted to the top of the Lower Turonian Watinoceras devonense Zone, much longer (~1.05 Ma) than in the Northern Province. These differences are discussed with respect to (1) the Cenomanian–Turonian Anoxic Event (CTAE) hypothesis when the ocean-continent-atmosphere systems were linked, (2) limitations of chemostratigraphic global correlation, and (3) the Cenomanian–Turonian Anoxic Event Recovery (CTOAER), a new term to define the varying lengths of time it took different oceans and seas to recover once the linked ocean-continent-atmosphere system was over. The possibility is considered that glacio-eustasy (the glacial control hypothesis of Jeans et al. 1991) with the waxing and waning of polar ice sheets, in association with the degassing of large igneous provinces, may have set the scene for the development of the Cenomanian–Turonian Anoxic Event (CTAE)