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Introduction: Bovine mastitis caused by Escherichia coli compromises animal health and inflicts substantial product losses in dairy farming. It may manifest as subclinical through severe acute disease and can be transient or persistent in nature. Little is known about bacterial factors that impact clinical outcomes or allow some strains to outcompete others in the mammary gland (MG) environment. Mastitis-associated E. coli (MAEC) may have distinctive characteristics which may contribute to the varied nature of the disease. Given their high levels of intraspecies genetic variability, virulence factors of commonly used MAEC model strains may not be relevant to all members of this group. Methods: In this study, we sequenced the genomes of 96 MAEC strains isolated from cattle with clinical mastitis (CM). We utilized clinical severity data to perform genome-wide association studies to identify accessory genes associated with strains isolated from mild or severe CM, or with high or low competitive fitness during in vivo competition assays. Genes associated with mastitis pathogens or commensal strains isolated from bovine sources were also identified. Results: A type-2 secretion system (T2SS) and a chitinase (ChiA) exported by this system were strongly associated with pathogenic isolates compared with commensal strains. Deletion of chiA from MAEC isolates decreased their adherence to cultured bovine mammary epithelial cells. Discussion: The increased fitness associated with strains possessing this gene may be due to better attachment in the MG. Overall, these results provide a much richer understanding of MAEC and suggest bacterial processes that may underlie the clinical diversity associated with mastitis and their adaptation to this unique environment. [ABSTRACT FROM AUTHOR]

Introduction: The microbial interactions within the human microbiome are complex, and few methods are available to identify these interactions within a longitudinal microbial abundance framework. Existing methods typically impose restrictive constraints, such as requiring long sequences and equal spacing, on the data format which in many cases are violated. Methods: To identify microbial interaction networks (MINs) with general longitudinal data settings, we propose a stationary Gaussian graphical model (SGGM) based on 16S rRNA gene sequencing data. In the SGGM, data can be arbitrarily spaced, and there are no restrictions on the length of data sequences from a single subject. Based on the SGGM, EM -type algorithms are devised to compute the L1-penalized maximum likelihood estimate of MINs. The algorithms employ the classical graphical LASSO algorithm as the building block and can be implemented efficiently. Results: Extensive simulation studies show that the proposed algorithms can significantly outperform the conventional algorithms if the correlations among the longitudinal data are reasonably high. When the assumptions in the SGGM areviolated, e.g., zero inflation or data from heterogeneous microbial communities, the proposed algorithms still demonstrate robustness and perform better than the other existing algorithms. The algorithms are applied to a 16S rRNA gene sequencing data set from patients with cystic fibrosis. The results demonstrate strong evidence of an association between the MINs and the phylogenetic tree, indicating that the genetically related taxa tend to have more/ stronger interactions. These results strengthen the existing findings in literature. Discussion: The proposed algorithms can potentially be used to explore the network structure in genome, metabolome etc. as well. [ABSTRACT FROM AUTHOR]

Sustainability is at the forefront of all research carried out at University of Leicester. There are three main groups contributing to the surface finishing effort: the Centre for Sustainable Materials Processing, the Mechanics of Materials research group and Space Park Leicester; however many collaborations occur across the institution and with industrial partners, including the Materials Innovation Centre with TWI Ltd. The ongoing projects vary across a range of themes, from forensic science to batteries and energy storage. This work aims to give a brief overview of the research groups, centres and institutes, and highlights some relevant projects that fall within the scope of Transactions of the IMF. [ABSTRACT FROM AUTHOR]

The ability of the public to remain psychologically resilient in the face of public health emergencies and disasters (such as the COVID-19 pandemic) is a key factor in the effectiveness of a national response to such events. Community resilience and social capital are often perceived as beneficial and ensuring that a community is socially and psychologically resilient may aid emergency response and recovery. This review presents a synthesis of literature which answers the following research questions: How are community resilience and social capital quantified in research?; What is the impact of community resilience on mental wellbeing?; What is the impact of infectious disease outbreaks, disasters and emergencies on community resilience and social capital?; and, What types of interventions enhance community resilience and social capital? A scoping review procedure was followed. Searches were run across Medline, PsycInfo, and EMBASE, with search terms covering both community resilience and social capital, public health emergencies, and mental health. 26 papers met the inclusion criteria. The majority of retained papers originated in the USA, used a survey methodology to collect data, and involved a natural disaster. There was no common method for measuring community resilience or social capital. The association between community resilience and social capital with mental health was regarded as positive in most cases. However, we found that community resilience, and social capital, were initially negatively impacted by public health emergencies and enhanced by social group activities. Several key recommendations are proposed based on the outcomes from the review, which include: the need for a standardised and validated approach to measuring both community resilience and social capital; that there should be enhanced effort to improve preparedness to public health emergencies in communities by gauging current levels of community resilience and social capital; that community resilience and social capital should be bolstered if areas are at risk of disasters or public health emergencies; the need to ensure that suitable short-term support is provided to communities with high resilience in the immediate aftermath of a public health emergency or disaster; the importance of conducting robust evaluation of community resilience initiatives deployed during the COVID-19 pandemic. [ABSTRACT FROM AUTHOR]

The ability of the public to remain psychologically resilient in the face of public health emergencies and disasters (such as the COVID-19 pandemic) is a key factor in the effectiveness of a national response to such events. Community resilience and social capital are often perceived as beneficial and ensuring that a community is socially and psychologically resilient may aid emergency response and recovery. This review presents a synthesis of literature which answers the following research questions: How are community resilience and social capital quantified in research?; What is the impact of community resilience on mental wellbeing?; What is the impact of infectious disease outbreaks, disasters and emergencies on community resilience and social capital?; and, What types of interventions enhance community resilience and social capital? A scoping review procedure was followed. Searches were run across Medline, PsycInfo, and EMBASE, with search terms covering both community resilience and social capital, public health emergencies, and mental health. 26 papers met the inclusion criteria. The majority of retained papers originated in the USA, used a survey methodology to collect data, and involved a natural disaster. There was no common method for measuring community resilience or social capital. The association between community resilience and social capital with mental health was regarded as positive in most cases. However, we found that community resilience, and social capital, were initially negatively impacted by public health emergencies and enhanced by social group activities. Several key recommendations are proposed based on the outcomes from the review, which include: the need for a standardised and validated approach to measuring both community resilience and social capital; that there should be enhanced effort to improve preparedness to public health emergencies in communities by gauging current levels of community resilience and social capital; that community resilience and social capital should be bolstered if areas are at risk of disasters or public health emergencies; the need to ensure that suitable short-term support is provided to communities with high resilience in the immediate aftermath of a public health emergency or disaster; the importance of conducting robust evaluation of community resilience initiatives deployed during the COVID-19 pandemic. [ABSTRACT FROM AUTHOR]

Objective: Co‐occurring anti‐tripartite motif‐containing protein 9 and 67 autoantibodies (TRIM9/67‐IgG) have been reported in only a very few cases of paraneoplastic cerebellar syndrome. The value of these biomarkers and the most sensitive methods of TRIM9/67‐IgG detection are not known. Methods: We performed a retrospective, multicenter study to evaluate the cerebrospinal fluid and serum of candidate TRIM9/67‐IgG cases by tissue‐based immunofluorescence, peptide phage display immunoprecipitation sequencing, overexpression cell‐based assay (CBA), and immunoblot. Cases in which TRIM9/67‐IgG was detected by at least 2 assays were considered TRIM9/67‐IgG positive. Results: Among these cases (n = 13), CBA was the most sensitive (100%) and revealed that all cases had TRIM9 and TRIM67 autoantibodies. Of TRIM9/67‐IgG cases with available clinical history, a subacute cerebellar syndrome was the most common presentation (n = 7/10), followed by encephalitis (n = 3/10). Of these 10 patients, 70% had comorbid cancer (7/10), 85% of whom (n = 6/7) had confirmed metastatic disease. All evaluable cancer biopsies expressed TRIM9 protein (n = 5/5), whose expression was elevated in the cancerous regions of the tissue in 4 of 5 cases. Interpretation: TRIM9/67‐IgG is a rare but likely high‐risk paraneoplastic biomarker for which CBA appears to be the most sensitive diagnostic assay. ANN NEUROL 2023;94:1086–1101 [ABSTRACT FROM AUTHOR]

The development of the process to produce Metal Matrix Nanocomposite (MMNC) coatings can provide opportunity for the enhancement of mechanical and electrical properties. This research uses speciation-simulating software to screen formulations for producing nanocomposites by pulse-reverse plating (PRP). PRP is used as a controlled delivery mechanism to attract a high concentration of nanoparticles to the coating during the anodic pulse which are subsequently captured in the cathodic pulse. A disadvantage is that the anodic pulse generates passivating hydroxide layers leading to poor adhesion. Speciation plots assess the stabilising effect of chosen complexants (gluconate and glycine) within electrolytes with the aim of diminishing hydroxide formation. To confirm bath formulation effectiveness before nanoparticle incorporation, UV-Vis spectroscopy and electrodeposition were used. Gluconate and glycine both theoretically produce highly stable complexes and also produce uniform copper deposits supporting the stabilisation effect observed in theoretical studies. This work therefore supports the use of these complexants for future stages of this research. [ABSTRACT FROM AUTHOR]

In certain applications, native surface patterns can be used in place of speckle patterns in digital image correlation (DIC). This paper explores the feasibility of using text as a native speckle pattern in DIC. Five text speckle patterns are tested in three different scenarios: a rigid body translation test, a rigid body rotation test, and an out of plane bending test. The patterns are benchmarked against a sixth, random speckle pattern applied using traditional DIC speckling methods. Rigid body translation tests are additionally performed on text patterns with varying font types and line spacings. In general, text patterns have good contrast, but low density as line spacing increases. Measurement uncertainty for the text patterns was comparable to measurement uncertainty in the random speckle pattern. Results from these tests show that while text patterns cannot be expected to perform better than a traditional DIC speckle pattern, text patterns can be effective speckle patterns in situations where already present on a specimen and applying a traditional speckle pattern is difficult. [ABSTRACT FROM AUTHOR]

In light of the low signal-to-noise nature of many large biological data sets, we propose a novel method to learn the structure of association networks using Gaussian graphical models combined with prior knowledge. Our strategy includes two parts. In the first part, we propose a model selection criterion called structural Bayesian information criterion, in which the prior structure is modeled and incorporated into Bayesian information criterion. It is shown that the popular extended Bayesian information criterion is a special case of structural Bayesian information criterion. In the second part, we propose a two-step algorithm to construct the candidate model pool. The algorithm is data-driven and the prior structure is embedded into the candidate model automatically. Theoretical investigation shows that under some mild conditions structural Bayesian information criterion is a consistent model selection criterion for high-dimensional Gaussian graphical model. Simulation studies validate the superiority of the proposed algorithm over the existing ones and show the robustness to the model misspecification. Application to relative concentration data from infant feces collected from subjects enrolled in a large molecular epidemiological cohort study validates that metabolic pathway involvement is a statistically significant factor for the conditional dependence between metabolites. Furthermore, new relationships among metabolites are discovered which can not be identified by the conventional methods of pathway analysis. Some of them have been widely recognized in biological literature. [ABSTRACT FROM AUTHOR]

Digital Image Correlation (DIC) is a camera-based method of measuring displacement and strain. High-temperature DIC is challenging due to light emitted from the sample which can saturate the image. This effect can be mitigated using optical bandpass filters, but the maximum sample temperature range of DIC remains dependent on the camera and camera settings. Among camera settings, bit depth, also referred to as color depth or number of bits, has received insufficient attention in high-temperature DIC literature. In this work, the effect of bit depth on DIC measurements is investigated both analytically and experimentally. It is shown that if image noise is sufficiently low, then increasing bit depth reduces DIC random error. A new metric, the effective number of bits, is presented to determine the appropriate number of bits for DIC images. Using increased bit depth, reduced exposure time, and low-noise images, the maximum sample temperature for DIC measurements was shown to increase without negatively impacting random error. [ABSTRACT FROM AUTHOR]

Background Staff working in intensive care units (ICUs) have faced significant challenges during the COVID-19 pandemic which have the potential to adversely affect their mental health. Aims To identify the rates of probable mental health disorder in staff working in ICUs in nine English hospitals during June and July 2020. Methods An anonymized brief web-based survey comprising standardized questionnaires examining depression, anxiety symptoms, symptoms of post-traumatic stress disorder (PTSD), well-being and alcohol use was administered to staff. Results Seven hundred and nine participants completed the surveys comprising 291 (41%) doctors, 344 (49%) nurses and 74 (10%) other healthcare staff. Over half (59%) reported good well-being; however, 45% met the threshold for probable clinical significance on at least one of the following measures: severe depression (6%), PTSD (40%), severe anxiety (11%) or problem drinking (7%). Thirteen per cent of respondents reported frequent thoughts of being better off dead, or of hurting themselves in the past 2 weeks. Within the sample used in this study, we found that doctors reported better mental health than nurses across a range of measures. Conclusions We found substantial rates of probable mental health disorders, and thoughts of self-harm, amongst ICU staff; these difficulties were especially prevalent in nurses. Whilst further work is needed to better understand the real level of clinical need amongst ICU staff, these results indicate the need for a national strategy to protect the mental health, and decrease the risk of functional impairment, of ICU staff whilst they carry out their essential work during COVID-19. [ABSTRACT FROM AUTHOR]

This article presents various designs of toroidal air-core transformers utilizing a 3-D printing and electroplating fabrication methodology. For certain applications and switching frequency regimes, limitations in core-based magnetics force circuit designers to use air-core components, which are conventionally wire-wound, and thus, constrained to simple structures with poor copper coverage. 3-D printing offers a solution to this constraint and provides more flexibility for transformer designs. This article includes design calculations, finite-element method (FEM) simulations, and loss analysis for three different toroidal transformer designs: one which features nested toroids, coupling their N2 flux, the second which uses stacked toroids, coupling the one-turn flux, and the third which interleaves two windings. Furthermore, the manufacturing procedure presented in this article allows for accurate modeling of the transformer's inductance matrix, which is advantageous over hand-wound air-core components. Additionally, we provide experimental demonstrations, including the implementation of these transformers in 100-W, 30-MHz resonant converters. Lastly, COMSOL FEM design automation MATLAB scripts for the various inductors and transformers discussed in this article are publicly available in the paper by Z. Tong (2019), allowing for fast parametric modeling of magnetic designs. [ABSTRACT FROM AUTHOR]

Nanocomposite Co-Al2O3 electrodeposited coatings have been produced for the first time by pulse reverse plating (PRP) in conjunction with an anionic surfactant, sodium dodecylsulphate (SDS), by a similar method used for Co – IF WS2 deposition in previous work. The influence of two parameters on nanocomposite composition and morphology was investigated in this study: the SDS content of the bath was varied (from 0 to 0.8 g L−1) as well as the length of the cathodic pulse, from tc = 30 s to 120 s. In addition, the composites were also produced by direct current (DC) for comparison. Co-PTFE nanocomposites were also considered using the same approach. The coatings were characterised microstructurally by SEM, EDX, XRD, and mechanically with a Knoop microhardness test. For Co-Al2O3, the alumina particle content is high for PRP coatings compared to those produced by DC; a higher particle content was achieved at lower tc. Increasing SDS led to a peak in the particle content, followed by a reduction in the particle content with further increase in the SDS concentration. Cathode efficiency decreased with increasing tc, but is higher compared to the DC coatings. Particle surface coverage for both nanocomposites per pulse cycle follows a pattern for the PRP coatings with varying SDS content that is different to that achieved with DC coatings. Increasing particle content led to a decrease in crystallite size, which indicated that the particle inclusion led to grain size refinement. However, analysis of the hardness tests showed that the Al2O3 particles predominantly provide dispersion strengthening. For Co-PTFE the PRP mechanism was shown to be ineffective in producing composite coatings. This is thought to be due to the larger size of the particle. [ABSTRACT FROM AUTHOR]

Objectives Interictal epileptiform discharges ( IEDs) have been linked to memory impairment, but the spatial and temporal dynamics of this relationship remain elusive. In the present study, we aim to systematically characterize the brain areas and times at which IEDs affect memory. Methods Eighty epilepsy patients participated in a delayed free recall task while undergoing intracranial electroencephalography ( EEG) monitoring. We analyzed the locations and timing of IEDs relative to the behavioral data in order to measure their effects on memory. Results Overall IED rates did not correlate with task performance across subjects (r = 0.03, p = 0.8). However, at a finer temporal scale, within-subject memory was negatively affected by IEDs during the encoding and recall periods of the task but not during the rest and distractor periods (p < 0.01, p < 0.001, p = 0.3, and p = 0.8, respectively). The effects of IEDs during encoding and recall were stronger in the left hemisphere than in the right (p < 0.05). Of six brain areas analyzed, IEDs in the inferior-temporal, medial-temporal, and parietal areas significantly affected memory (false discovery rate < 0.05). Significance These findings reveal a network of brain areas sensitive to IEDs with key nodes in temporal as well as parietal lobes. They also demonstrate the time-dependent effects of IEDs in this network on memory. [ABSTRACT FROM AUTHOR]

Peatland measurements of CO and CH flux were obtained at scales appropriate to the in situ biological community below the tree layer to demonstrate representativeness of the spruce and peatland responses under climatic and environmental change (SPRUCE) experiment. Surface flux measurements were made using dual open-path analyzers over an area of 1.13 m in daylight and dark conditions along with associated peat temperatures, water table height, hummock moisture, atmospheric pressure and incident radiation data. Observations from August 2011 through December 2014 demonstrated seasonal trends correlated with temperature as the dominant apparent driving variable. The S1-Bog for the SPRUCE study was found to be representative of temperate peatlands in terms of CO and CH flux. Maximum net CO flux in midsummer showed similar rates of C uptake and loss: daytime surface uptake was −5 to −6 µmol m s and dark period loss rates were 4-5 µmol m s (positive values are carbon lost to the atmosphere). Maximum midsummer CH-C flux ranged from 0.4 to 0.5 µmol m s and was a factor of 10 lower than dark CO-C efflux rates. Midwinter conditions produced near-zero flux for both CO and CH with frozen surfaces. Integrating temperature-dependent models across annual periods showed dark CO-C and CH-C flux to be 894 ± 34 and 16 ± 2 gC m y, respectively. Net ecosystem exchange of carbon from the shrub-forb- Sphagnum-microbial community (excluding tree contributions) ranged from −3.1 gCO-C m y in 2013, to C losses from 21 to 65 gCO-C m y for the other years. [ABSTRACT FROM AUTHOR]

Background Postal questionnaires remain an important method of collecting data in trials. However, a high non-response rate can lead to biases, which may undermine the validity of the study. Aims To assess a simple method of trying to improve response rates in an occupational health trial evaluating an intervention to prevent hand dermatitis in nurses. Methods The trial employed questionnaires at t = 0, t = 1 month and t = 12 months. The t = 1 month questionnaire was posted to study participants (student and intensive care nurses) together with a free postage reply envelope. After 2 weeks, an e-mail was sent to non-responders reinforcing the need for completed questionnaires to be returned. Two weeks later, non-responders were sent another hard copy of the questionnaire, along with an accompanying letter. Six weeks after posting the initial questionnaires, non-responders were sent an SMS text message or were telephoned to remind them to return the questionnaire. Results The response rates for the 744 student nurses were 8% (no reminder), 27% (after first reminder), 22% (after second reminder) and 27% (after the third reminder), resulting in a response rate of 63%. The response rates for the 959 intensive care nurses were 9% (no reminder), 24% (after first reminder), 24% (after second reminder) and 31% (after third reminder), resulting in a final response rate of 63%. Conclusions We found that a series of regular reminders including a third, personalized reminder by SMS text or telephone had a positive impact on non-responders. [ABSTRACT FROM AUTHOR]

Ten years ago, it was announced that the Joint Genome Institute with funds provided by the Department of Energy, Office of Science, Biological and Environmental Research would sequence the black cottonwood (Populus trichocarpa Torr. & Gray) genome. This landmark decision was the culmination of work by the forest science community to develop Populus as a model system. Since its public release in late 2006, the availability of the Populus genome has spawned research in plant biology, morphology, genetics and ecology. Here we address how the tree physiologist has used this resource. More specifically, we revisit our earlier contention that the rewards of sequencing the Populus genome would depend on how quickly scientists working with woody perennials could adopt molecular approaches to investigate the mechanistic underpinnings of basic physiological processes. Several examples illustrate the integration of functional and comparative genomics into the forest sciences, especially in areas that target improved understanding of the developmental differences between woody perennials and herbaceous annuals (e.g., phase transitions). Sequencing the Populus genome and the availability of genetic and genomic resources has also been instrumental in identifying candidate genes that underlie physiological and morphological traits of interest. Genome-enabled research has advanced our understanding of how phenotype and genotype are related and provided insights into the genetic mechanisms whereby woody perennials adapt to environmental stress. In the future, we anticipate that low-cost, high-throughput sequencing will continue to facilitate research in tree physiology and enhance our understanding at scales of individual organisms and populations. A challenge remains, however, as to how genomic resources, including the Populus genome, can be used to understand ecosystem function. Although examples are limited, progress in this area is encouraging and will undoubtedly improve as future research targets the many unique aspects of Populus as a keystone species in terrestrial ecosystems. [ABSTRACT FROM AUTHOR]

Co–W alloys with 12–26 at.-%W (25–45 wt-%W) can be produced by electrodeposition from complexed aqueous plating baths. The deposits can be in the amorphous or nanostructured conditions, depending on the plating bath operations. Most recent attention has been focused on the nanocrystalline conditions which have hardness values in excess of 850 kg mm-2, which makes them competitive with hard engineering chromium. This may allow the coatings to replace hard Cr which is produced from hexavalent chromium baths having associated health and safety problems. Co–W coatings, 2–120 μm thick, can be deposited with a low incidence of cracking, with good corrosion and wear properties (dry and lubricated) when deposited on a variety of steel substrates. The underlying reasons, i.e. the amount of tungsten in solution, the density of grain boundaries and the reduction in bonding between coating and counterface under dry sliding conditions, which account for these enhanced properties are discussed. Potential applications are in many sectors of engineering including aerospace, hydraulics and automobile. [ABSTRACT FROM AUTHOR]

The problem of preprocessing transaction data for supervised fraud classification is considered. It is impractical to present an entire series of transactions to a fraud detection system, partly because of the very high dimensionality of such data but also because of the heterogeneity of the transactions. Hence, a framework for transaction aggregation is considered and its effectiveness is evaluated against transaction-level detection, using a variety of classification methods and a realistic cost-based performance measure. These methods are applied in two case studies using real data. Transaction aggregation is found to be advantageous in many but not all circumstances. Also, the length of the aggregation period has a large impact upon performance. Aggregation seems particularly effective when a random forest is used for classification. Moreover, random forests were found to perform better than other classification methods, including SVMs, logistic regression and KNN. Aggregation also has the advantage of not requiring precisely labeled data and may be more robust to the effects of population drift. [ABSTRACT FROM AUTHOR]

South Africa's National Water Act and National Water Resource Strategy set out an ambitious vision for Integrated Water Resources Management including a strong focus on the redistribution of water resources towards the poor and on empowering historically disadvantaged communities. To achieve this vision the Department of Water Affairs & Forestry (DWAF) has been pursuing a programme for devolving powers to 19 stakeholder-led catchment management agencies (CMAs) and more locally, transforming irrigation boards into more inclusive water user associations (WUAs), as well as creating new associations. Co-operative governance is a core principle of this programme. As well as being enshrined in South Africa's constitution, this principle is seen as key to enabling CMAs to implement their core functions, which include co-ordinating the activities of water users and water management institutions within their water management area. For WUAs also, the principle of co-operative governance is key to building engagement between White commercial farmers and emerging Black farmers, as well as (in some cases) engaging with a wider set of stakeholder interests including local government and environmental interests. Despite a commitment to the principle of co-operative governance, individual and institutional capacity for facilitating co-operative development processes is in relatively short supply within the South African water sector. This paper describes work-in-progress to build capacity in this area, working with: • DWAF's national Institutional Governance team • The Inkomati CMA (ICMA), the first of South Africa's new catchment management agencies • Two irrigation boards and a number of other stakeholders in the Mvoti catchment - with a view to the development of an appropriate institutional arrangement (WUA or otherwise) for the co-operative governance of this catchment. This paper focuses on the development of an interactive approach to capacity building in each of these three sites, drawing from a broad portfolio of approaches variously described as social learning, social appraisal, or whole system development. In the Inkomati we have worked primarily with the whole system approach known as Future Search, whereas in the Mvoti we have used the U-process and social appraisal as guiding metaphors and design principles. This paper describes some of our achievements, challenges and reflections to date, and argues that the interactive approaches we have been taking are better suited to the implementation of DWAF's institutional reform processes than the more established, top-down approaches, which involve issuing guidance, supported by training programmes. The paper concludes with a discussion of the implications for scaling up these types of approaches across the South African water system as a whole, and for the practice of integrated water resource management. [ABSTRACT FROM AUTHOR]

In predictive data mining, algorithms will be both optimized and compared using a measure of predictive performance. Different measures will yield different results, and it follows that it is crucial to match the measure to the true objectives. In this paper, we explore the desirable characteristics of measures for constructing and evaluating tools for mining plastic card data to detect fraud. We define two measures, one based on minimizing the overall cost to the card company, and the other based on minimizing the amount of fraud given the maximum number of investigations the card company can afford to make. We also describe a plot, analogous to the standard ROC, for displaying the performance trace of an algorithm as the relative costs of the two different kinds of misclassification-classing a fraudulent transaction as legitimate or vice versa-are varied. [ABSTRACT FROM AUTHOR]

Using the Teacher Career Cycle Model as the theoretical framework, this study extended our understanding of how teachers professionally develop during their first year of teaching. The purpose of this study was to describe the induction activities and socialization process that novice agricultural education teachers experience, and to determine their psychosocial attitude after completion of the first year of teaching. Thirty-one agricultural education teachers in their first year of teaching participated in the study, and both quantitative and qualitative research methodology was utilized to collect and analyze the data. Researchers concluded that factors related to the organizational environment of the school influence the induction stage of teaching. Novice teachers were not prepared for isolation and socialization issues, were challenged by complex program management responsibilities, and expressed frustration by the amount and quality of support that was provided by the school administrator. Novice teachers learned that they serve an important role in students' lives, and reported "love/hate" aspects of their career. It was determined through the use of a semantic differential scale that novice teachers concluded their first year of teaching with an overall positive psychosocial attitude. [ABSTRACT FROM AUTHOR]

In 'hard' numerate subjects of electrical/electronic engineering, student motivation is a difficult problem. Students must feel engaged and purposeful. The authors have worked closely together as a pan-European group to design a module that engages students via interesting practical work, integrating a number of subjects together, and achieving enhanced motivation. [ABSTRACT FROM AUTHOR]

A mass-balance bioaccumulation model was used to examine the bioaccumulation of benzo[a]pyrene (BaP) from ingested sediment by the deposit-feeding polychaete Abarenicola pacifica over a series of experiments employing nine different sediments. Through selective ingestion of fine-grained material, the worm was able to increase the BaP content of ingested sediment by 10–35% above that of the bulk material. During digestion, an average of 5–21% of the ingested BaP was absorbed from gut contents. The relative importance of ingestion as a route of BaP uptake was dependent on the time period of observation. Initial uptake of BaP was postulated to come from absorption of dissolved BaP across the body wall since, after short periods of exposure (<24 h), only 3–38% of observed BaP tissue concentrations could have been derived from ingested material. With time and with increased feeding activity, however, ingested sediment became the major source of BaP to the organism. After 72 h of exposure, 36–119% of the tissue BaP (mean = 77%) was estimated to have been derived from dietary absorption of ingested material, and with continued exposure the dietary route is likely to be as great or greater as the relative significance of the initial uptake from the dissolved phase diminishes. This work and other studies indicate that for many deposit feeders, ingested sediment can be the primary source for the bioaccumulation of hydrophobic toxicants. [ABSTRACT FROM AUTHOR]

An inhomogeneous plane wave, i.e., one having an exponential decay across the wavefront, may be used to model the sound incident on any reflecting boundary. If the decay is away from the boundary there is normally an element of reflection gain associated with the process, corresponding to a release of previously stored energy. This gain is in addition to the loss expected for an equivalent homogeneous wave. It is shown that the gain element is equal to the exponential decay in the inhomogeneous wave resolved across the horizontal beam displacement. This result holds very generally for transmission as well as reflection, for change of wave type, and for the gain element occurring when the incidence medium is lossy. In application to guided waves these results automatically ensure that the attenuation rate is the same, whether modeled by inhomogeneous waves with an element of gain, or by waves with a beam displacement. The incident inhomogeneous wave may be decomposed into a spectrum of homogeneous plane waves having a spread in angle. Similarly an attenuating mode may be regarded as propagating with a spread in equivalent ray angles. [ABSTRACT FROM AUTHOR]

Recent results showing the equivalence of mode attenuation per cycle and reflection loss of the equivalent ray did not hold in shallow water with a small number of modes. The failure is demonstrated to be linked to the concept and definition of a mode cycle distance for low mode density. Attenuation rates of modes and average attenuation rates of rays are now shown to be equal for all mode densities, provided the attenuation is not too large and the ray cycle distance is taken as the sum of the geometrically traced ray distance and the boundary beam displacement. [ABSTRACT FROM AUTHOR]

A concise energy-flux formulation is used to investigate the range- averaged acoustic propagation in ocean ducts. Examples treated have isovelocity, linear, and parabolic sound speed profiles. The results are expressed as the product of a scale factor and, for the latter two examples, a depth factor. The scale factor has a similar form in each case, and remains simple and easy to use even when the profile is asymmetrical and the parameters vary with range. The appropriate solution for transmission from an isovelocity duct to a duct of arbitrary profile is also given. Surprisingly, the depth factor generally has a nominal infinity when receiver depth equals source depth in an unchanging but stratified duct, or when velocity at the receiver equals that at the source, or for scaled depths in a range-dependent duct. These infinites are discussed from the flux, ray, and mode viewpoints and a ray-tracing demonstration is provided. For the special case of axial source and receiver, the character of the infinite is different, and an important point is that it occurs only for velocity minima sharper than that of the parabolic profile. The latter profile has in several respects a critical nature. [ABSTRACT FROM AUTHOR]

Even in isovelocity water the wave or modal nature of the sound propagation causes special effects at four particular depths. Thus, the range-averaged level shows a zero at the free surface, a maximum at the source depth, and effects of uncertain sign at the bottom and near the source complementary depth. These peaks show further curious behavior, akin to interference, as source depth is varied. The present source depth peaking is a wave effect in isovelocity water, in contrast with the flux-theory infinities predicted for refracting conditions. For large numbers of modes, the present source depth peak is normally 50% above the average, and this anticipates a similar wave-theory result for refracting conditions. [ABSTRACT FROM AUTHOR]

The formal energy-flux solution for range-averaged level in a varying duct depends on the definition of transmission loss, on the local impedances, and in a complicated way on the vertical angles and cross-track variations. But for most purposes a very simple low angle version is sufficiently accurate and well established to be virtually independent of the detailed profile. Surprisingly, the convergence factor with circular symmetry is also independent of the detailed profile; this is true for unbounded media as well. Depth transforms are presented for the angular distributions of intensity, initially without specific reference to sources. Angular distributions for discrete sources show some characteristic zeros and infinities. It is shown that only the Gaussian distribution is self-reproducing with changes in depth. The law of conjugate depths states that intensities will be equal at such depths, and it is expected that this law will be very robust. Work on these and allied energy-flux methods is reviewed. [ABSTRACT FROM AUTHOR]

Several theoretical results linking ray and normal-mode quantities are derived by assuming Wentzel-Kramers-Brillouin (WKB) solutions for the depth dependence of the acoustic field in both water and bottom. Some of the results are not new but are extended here to the general case of reflection from a structured, lossy bottom: (1) Mode and ray cycle distances are equal if the ray cycle distance includes the beam displacement on reflection; (2) cycle distance is simply related to the normalization of the normal modes; (3) mode attenuation per cycle is equal to bottom loss per bounce of the equivalent ray; (4) a complete normal-mode solution for water may be obtained from the plane-wave reflection coefficient with no further knowledge of the bottom; and (5) the WKB solution for the bottom is equivalent to a calculation assuming interfering geometric ray paths. [ABSTRACT FROM AUTHOR]

The loss on reflection of a homogeneous acoustic wave from the boundary of an absorbing fluid is derived in several ways, including a calculation based on the attenuation along the beam displacement. For a so-called inhomogeneous plane wave there is an extra term, and the overall effect can be a loss or a gain. The paper considers several approaches to mode attenuation in an isovelocity or Perkeris channel with a lossy lower medium. We compare the horizontal attenuation of a mode with the horizontal attenuation of a ray due to multiple reflection losses. For exact agreement at all angles it is necessary either to include the beam displacement in the cycle distance, or to use the reflection coefficient appropriate to inhomogeneous waves, but these latter provisos are important only for shallow water and modes near cutoff. Beam displacement plays a part in both the reflection loss and the cycle distance calculations, and these aspects may be generalized. [ABSTRACT FROM AUTHOR]

The pharmacokinetics and cantharides-induced blister fluid levels of norfloxacin were studied after a single 400 mg oral dose. The mean maximum serum level was 1.45 mg/l and occurred 1.5 h after administration. The serum half-life of norfloxacin was found to be 3.5 h. After 24 h 27% of the administered dose was recovered in the urine as microbiologically active compound. High urine levels were found. Rapid blister fluid penetration occurred, the maximum level (occurring between 2·3 h) was about 1 mg/l. Thereafter the blister fluid level exceeded the serum level, both declining in parallel. [ABSTRACT FROM PUBLISHER]

The leakage attenuation from a duct is simply related to the field level outside the duct, and the relation can be applied to the surface sound channel. High-frequency measurements over the Biscay Abyssal Plain support the predicted relation and indicate that the loss is mainly due to scattering at very shallow angles, presumably from the surface waves. Similarly low-frequency measurements in the same area show a diffraction loss occurring with effective angles that are again very shallow. Measurements by Reynolds and Pryce at 7.5 kHz are also shown to correspond very closely to low-angle scattering, ruling out any large contribution from entrained bubbles. In addition, it is possible to estimate the residual bulk absorption. But their results at 3.25 kHz show marked additional effects that are interpreted as wide-angle scattering and absorption due to small fish, and the existence of such deep-water fish attenuation is thought to be both novel and important. Use of our leakage relation has helped to identify and to disentangle five separate loss mechanisms. [ABSTRACT FROM AUTHOR]