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The only cases where exact distributions of estimates are known is for samples from exponential families, and then only for special functions of the parameters. So statistical inference was traditionally based on the asymptotic normality of estimates. To improve on this we need the Edgeworth expansion for the distribution of the standardised estimate. This is an expansion in n − 1 / 2 about the normal distribution, where n is typically the sample size. The first few terms of this expansion were originally given for the special case of a sample mean. In earlier work we derived it for any standard estimate, hugely expanding its application. We define an estimate w ^ of an unknown vector w in R p , as a standard estimate, if E w ^ → w as n → ∞ , and for r ≥ 1 the rth-order cumulants of w ^ have magnitude n 1 − r and can be expanded in n − 1. Here we present a significant extension. We give the expansion of the distribution of any smooth function of w ^ , say t (w ^) in R q , giving its distribution to n − 5 / 2 . We do this by showing that t (w ^) , is a standard estimate of t (w) . This provides far more accurate approximations for the distribution of t (w ^) than its asymptotic normality. [ABSTRACT FROM AUTHOR]

Interictal epileptiform discharges have been shown to propagate from focal epileptogenic sources as travelling waves or through more rapid white matter conduction. We hypothesize that both modes of propagation are necessary to explain interictal discharge timing delays. We propose a method that, for the first time, incorporates both propagation modes to identify unique potential sources of interictal activity. We retrospectively analysed 38 focal epilepsy patients who underwent intracranial EEG recordings and diffusion-weighted imaging for epilepsy surgery evaluation. Interictal discharges were detected and localized to the most likely source based on relative delays in time of arrival across electrodes, incorporating travelling waves and white matter propagation. We assessed the influence of white matter propagation on distance of spread, timing and clinical interpretation of interictal activity. To evaluate accuracy, we compared our source localization results to earliest spiking regions to predict seizure outcomes. White matter propagation helps to explain the timing delays observed in interictal discharge sequences, underlying rapid and distant propagation. Sources identified based on differences in time of receipt of interictal discharges are often distinct from the leading electrode location. Receipt of activity propagating rapidly via white matter can occur earlier than more local activity propagating via slower cortical travelling waves. In our cohort, our source localization approach was more accurate in predicting seizure outcomes than the leading electrode location. Inclusion of white matter in addition to travelling wave propagation in our model of discharge spread did not improve overall accuracy but allowed for identification of unique and at times distant potential sources of activity, particularly in patients with persistent postoperative seizures. Since distant white matter propagation can occur more rapidly than local travelling wave propagation, combined modes of propagation within an interictal discharge sequence can decouple the commonly assumed relationship between spike timing and distance from the source. Our findings thus highlight the clinical importance of recognizing the presence of dual modes of propagation during interictal discharges, as this may be a cause of clinical mislocalization. [ABSTRACT FROM AUTHOR]

While seizure activity may be electrographically widespread, increasing evidence has suggested that ictal discharges may in fact represent travelling waves propagated from a focal seizure source. Interictal epileptiform discharges (IEDs) are an electrographic manifestation of excessive hypersynchronization of cortical activity that occur between seizures and are considered a marker of potentially epileptogenic tissue. The precise relationship between brain regions demonstrating IEDs and those involved in seizure onset, however, remains poorly understood. Here, we hypothesize that IEDs likewise reflect the receipt of travelling waves propagated from the same regions which give rise to seizures. Forty patients from our institution who underwent invasive monitoring for epilepsy, proceeded to surgery and had at least one year of follow-up were included in our study. Interictal epileptiform discharges were detected using custom software, validated by a clinical epileptologist. We show that IEDs reach electrodes in sequences with a consistent temporal ordering, and this ordering matches the timing of receipt of ictal discharges, suggesting that both types of discharges spread as travelling waves. We use a novel approach for localization of ictal discharges, in which time differences of discharge receipt at nearby electrodes are used to compute source location; similar algorithms have been used in acoustics and geophysics. We find that interictal discharges co-localize with ictal discharges. Moreover, interictal discharges tend to localize to the resection territory in patients with good surgical outcome and outside of the resection territory in patients with poor outcome. The seizure source may originate at, and also travel to, spatially distinct IED foci. Our data provide evidence that interictal discharges may represent travelling waves of pathological activity that are similar to their ictal counterparts, and that both ictal and interictal discharges emerge from common epileptogenic brain regions. Our findings have important clinical implications, as they suggest that seizure source localizations may be derived from interictal discharges, which are much more frequent than seizures. [ABSTRACT FROM AUTHOR]

Taxonomic free sorting ( TFS) is a fast, reliable and new technique in sensory science. The method extends the typical free sorting task where stimuli are grouped according to similarities, by asking respondents to combine their groups two at a time to produce a hierarchy. Previously, TFS has been used for the visual assessment of packaging whereas this study extends the range of potential uses of the technique to incorporate full sensory analysis by the target consumer, which, when combined with hedonic liking scores, was used to generate a novel preference map. Furthermore, to fully evaluate the efficacy of using the sorting method, the technique was evaluated with a healthy older adult consumer group. Participants sorted eight products into groups and described their reason at each stage as they combined those groups, producing a consumer-specific vocabulary. This vocabulary was combined with hedonic data from a separate group of older adults, to give the external preference map. Taxonomic sorting is a simple, fast and effective method for use with older adults, and its combination with liking data can yield a preference map constructed entirely from target consumer data. Practical Applications Generating diagnostic sensory data directly from target consumers is a challenge in sensory science. Taxonomic free sorting ( TFS) is a new and efficient sorting technique that aims to determine the sensory characteristics of products that are important to specific consumer cohorts. The hierarchical stages of TFS gives a better indication of the similarities and differences of a sample set and in this study was combined with consumer hedonic data to generate a preference map. In this study the attributes of the products assessed were provided directly by older consumers, without the need for training or prompting. TFS is a quick and effective method to give clear guidance of positive and negative characteristics of products according to the target consumer, as well as involving the specific consumer audience throughout the testing process. [ABSTRACT FROM AUTHOR]

Oral nutritional supplement drinks (ONS) are beverages high in dairy proteins that are prescribed to individuals at risk of malnutrition. Consumption of ONS is poor in elderly care facilities, with patients commenting that the sensory attributes of these drinks reduce their enjoyment and willingness to consume. Mouth drying is an attribute of ONS found to build with repeated consumption, which may further limit liking of these products. This study investigated the sources of drying sensations by sequential profiling, with a trained sensory panel rating a range of model milk systems and ONS over repeated sips and during after-effects. Sequential profiling found that fortification of milk with both caseinate and whey protein concentrate significantly increased the perception of mouth drying over repeated consumption, increasing by between 35 and 85% over consumption of 40 mL. Enrichment of ONS with either whey protein concentrate or milk protein concentrate to a total protein content of 8.7% (wt/wt) resulted in whey and casein levels of 4.3:4.4% and 1.7:7.0% respectively. The product higher in whey protein was substantially more mouth drying, implying that whey proteins may be the most important contributor to mouth drying in ONS. However, efforts to mask mouth drying of protein-fortified milk by increasing sweetness or fat level were unsuccessful at the levels tested. Increasing the viscosity of protein-fortified milk led to a small but significant reduction in mouth drying. However, this approach was not successful when tested within complete ONS. Further analysis is required into the mechanism of protein-derived mouth drying to mask negative sensations and improve the enjoyment and consumption of protein-rich ONS. [ABSTRACT FROM AUTHOR]

Suppose that we are monitoring incoming observations for a change in mean via a cumulative sum (CUSUM) test statistic. The usual nonparametric methods give first- and second-order approximations for the one- and two-sided cases. Withers and Nadarajah (Statistics and Probability Letters, 79, 2009, 689–697) and Withers and Nadarajah (Statistics and Probability Letters, 79, 2009, 2242–2250) showed how to improve the order of these approximations for linear statistics and for nonlinear statistics with non-zero asymptotic variances. Here, extensions are provided for nonlinear statistics with zero asymptotic variances and for multivariate statistics. [ABSTRACT FROM PUBLISHER]

Let Mn be the maximum of a random sample from F(x) on R. It is known that there exists gn: R → R such that gn (Mn) ℒ→ Y, nondegenerate, as n →∞ if and only if ¯F (x) / ¯F (x-) → 1 as x → ∞, where ¯F (x) = 1 - F (x). This condition holds for F continuous but fails, for example, for F Poisson and negative binomial. We consider the classes of distributions ¯F (x) = c xβ exp(α x ) x-x { 1 + o (1) } and ¯F (x) = d xc exp (-ax) { 1+o(1) } as x → ∞. These classes include the Poisson and negative binomial distributions for x an integer but not for general x. We show that (Mn - an)/bnℒ→Y as n → ∞ for some an and bn, where Y is a Gumbel random variable with distribution function exp { -exp (-y)}, -∞ < y < ∞. [ABSTRACT FROM AUTHOR]

The article presents a study on the characterization of phosphorus (P) sources in catchment basins. The importance of P sources identification is said to be crucial in preventing eutrophication that is primarily caused by agriculture-related activities. This study on watersheds analyzed samples of soil, stream, and various storm runoff sites such as field surface runoff and farm yards. The P concentration on streams and the mobilization of dissolved P are estimated using the environmental soil test to determine the potential for sediment and P transfer in runoff from agricultural land (DESPRAL). It concludes that Great Britain's Environmental Agency needs more than the England Catchment Sensitive Farming Delivery Initiative (ECSFDI) program to achieve good water quality in England.

There are advantages in viewing orthogonal functions as functions generated by a random variable from a basis set of functions. Let Y be a random variable distributed uniformly on [0, 1]. We give two ways of generating the Zernike radial polynomials with parameter l, {Zll+2n(x), n ≥ 0}. The first is using the standard basis {xn, n ≥ 0} and the random variable Y 1/(l+1). The second is using the nonstandard basis {xl+2n, n ≥ 0} and the random variable Y 1/2. Zernike polynomials are important in the removal of lens aberrations, in characterizing video images with a small number of numbers, and in automatic aircraft identification. [ABSTRACT FROM AUTHOR]

Although introduced into UK farming to help ensure more even application of agrochemicals, tramlines (marked wheelways through crops) are a potential cause of surface runoff and transfer of diffuse pollutants, including sediment and phosphorus (P), into watercourses. To help quantify these potential effects, the impact of tramlines on sediment and P movement in surface runoff was assessed on an erosion-prone sloping (5°) fine sandy soil over two successive winters. Three replicate and hydrologically isolated runoff plots measuring 15 m long and 2 m wide, and either with, or without, a tramline, were established on field demonstration areas which had received different soil (traditionally ploughed vs. reduced cultivated) and crop (early vs. late drilling) management practices. Reduced cultivation (minimum tillage) consisted of heavy discing (5–8 cm depth) instead of ploughing (20–25 cm depth). Over monitoring periods ranging up to 5 months, plots with tramlines running up and down the slope generated, on average, 46% more runoff (+1–2 mm) compared with plots without tramlines on ploughed soils. This extra runoff resulted in up to fivefold greater sediment loss (+0.4 t ha−1) and up to fourfold greater total P loss (+0.3 kg ha−1) from the plots. However, the presence of tramlines had no significant impact on runoff, or sediment and P transfers, where the soil received reduced cultivation. Plots with tramlines that were partially crop covered, or which ran across the slope rather than up and down the slope, produced the same amount of runoff, sediment and P transfer as plots without tramlines. Greatest entrainment of sediment and P in runoff occurred where tramlines coarsely indented the soil, or caused erosion rills to form. Establishing tramlines in dry soils reduced the degree of soil indentation and the risk of channelled runoff causing sediment and P entrainment. The data suggest that tramlines can be managed more sensitively on erosion vulnerable soils to help minimize the risk of sediment and P pollution of our surface waters, and various options are discussed. [ABSTRACT FROM AUTHOR]

This paper describes the equipment test facility and setup that has been developed in the laboratory and the investigation into both the filtration and reverse flow modes of low-density rigid ceramic filters at ambient conditions. The purpose is to study the fluid behavior by conducting experiments to investigate the pressure drop and the velocity profile along a filter element. Two different ceramic filter media were used in the majority of this work. Cerafil XS-1000 is the current product from Cerel(cylindrical) and the tapered filter, which is a novel design of the ceramic filter tailor made for this study. Both the filtration and reverse flow cleaning results suggest that a more uniform pressure generation is found in tapered filters than it is the cylindrical filters. The origin of nonuniformity in pressure difference across the wall, in both the filtration and cleaning modes, is internal(axial) pressure drop that can be reduced by reducing the axial gas velocity, which obviously takes its highest value towards the open end(in both filtration and cleaning modes). [ABSTRACT FROM AUTHOR]

Carole Withers reviews the literature surrounding the link between sudden infant death and babies who share beds with their parents. [ABSTRACT FROM AUTHOR]

Hermite polynomials have applications in almost every area of electrical and electronic engineering. Simple (hitherto unknown) representations are derived for the Hermite polynomials. For simplicity, the univariate case is considered. The same result holds for the multivariate and complex Hermite polynomials. [ABSTRACT FROM AUTHOR]

Given their frontline role in Australia and Aotearoa New Zealand (ANZ) healthcare, trainee medical officers (TMOs) will play a crucial role in the development and use of artificial intelligence (AI) for clinical care, ongoing medical education and research. As 'digital natives', particularly those with technical expertise in AI, TMOs should also be leaders in informing the safe uptake and governance of AI within ANZ healthcare as they have a practical understanding of its associated risks and benefits. However, this is only possible if a culture of broad collaboration is instilled while the use of AI in ANZ is still in its initial phase., (© 2024 The Author(s). Internal Medicine Journal published by John Wiley & Sons Australia, Ltd on behalf of Royal Australasian College of Physicians.)

Background: Existing research highlights the link between certain personality traits and mental health in surgeons. However, little research has explored the important role of psychological skills and qualities in potentially explaining this link. A cross-sectional survey of UK-based surgeons was used to examine whether two such skills (psychological flexibility and resilience) helped to explain why certain personality traits might be linked to mental health in surgeons., Method: An online survey comprising measures of personality (neuroticism, extraversion and conscientiousness), psychological skills/qualities (psychological flexibility and resilience) and mental health (depression, anxiety, stress and burnout) was sent to surgeons practising in the UK. Mediation analyses were used to examine the potential mediating role of psychological flexibility and resilience in explaining the relationship between personality factors and mental health., Results: A total of 348 surgeons completed the survey. In all 12 mediation models, psychological flexibility and/or resilience played a significant role in explaining the relationship between personality traits (neuroticism, extraversion and conscientiousness) and mental health (depression, anxiety and burnout)., Conclusion: Findings suggest that it is not only a surgeon's personality that is associated with their mental health, but the extent to which a surgeon demonstrates specific psychological qualities and skills (psychological flexibility and resilience). This has important implications for improving surgeons' mental wellbeing, because psychological flexibility and resilience are malleable, and can be successfully targeted with interventions in a way that personality traits cannot., (© The Author(s) 2024. Published by Oxford University Press on behalf of BJS Foundation Ltd.)

A 17-y-old Arabian mare was presented to the Auburn Large Animal Veterinary Teaching Hospital with a long-term history of intermittent mild recurrent colic that responded to medical treatment. CBC revealed mild lymphopenia; serum biochemistry findings were of increased gamma-glutamyl transferase and creatine kinase activities, hyperferremia, hyperglycemia, hypomagnesemia, and hypokalemia. Abdominocentesis was compatible with low-protein transudate. Due to the progression and duration of clinical signs, the owner elected euthanasia. Postmortem examination and histopathology confirmed a cholangiocarcinoma. The neoplastic cells were arranged in large cysts containing lakes of mucin that comprised 90% of the tumor volume; thus, a mucinous variant was determined. The neoplastic cells had strong cytoplasmic immunolabeling for cytokeratin 19 and lacked immunolabeling for hepatocyte paraffin 1, supporting bile duct origin. Cholangiocarcinomas are infrequent tumors in horses with nonspecific and slow progressive clinical signs, including recurrent colic. Mucinous cholangiocarcinomas are seldom reported in veterinary medicine and, to our knowledge, have not been reported previously in horses., Competing Interests: Declaration of conflicting interestsThe authors declared no potential conflicts of interest concerning the research, authorship, and/or publication of this article.

Background: Among critically ill adults undergoing tracheal intubation, hypoxemia increases the risk of cardiac arrest and death. The effect of preoxygenation with noninvasive ventilation, as compared with preoxygenation with an oxygen mask, on the incidence of hypoxemia during tracheal intubation is uncertain., Methods: In a multicenter, randomized trial conducted at 24 emergency departments and intensive care units in the United States, we randomly assigned critically ill adults (age, ≥18 years) undergoing tracheal intubation to receive preoxygenation with either noninvasive ventilation or an oxygen mask. The primary outcome was hypoxemia during intubation, defined by an oxygen saturation of less than 85% during the interval between induction of anesthesia and 2 minutes after tracheal intubation., Results: Among the 1301 patients enrolled, hypoxemia occurred in 57 of 624 patients (9.1%) in the noninvasive-ventilation group and in 118 of 637 patients (18.5%) in the oxygen-mask group (difference, -9.4 percentage points; 95% confidence interval [CI], -13.2 to -5.6; P<0.001). Cardiac arrest occurred in 1 patient (0.2%) in the noninvasive-ventilation group and in 7 patients (1.1%) in the oxygen-mask group (difference, -0.9 percentage points; 95% CI, -1.8 to -0.1). Aspiration occurred in 6 patients (0.9%) in the noninvasive-ventilation group and in 9 patients (1.4%) in the oxygen-mask group (difference, -0.4 percentage points; 95% CI, -1.6 to 0.7)., Conclusions: Among critically ill adults undergoing tracheal intubation, preoxygenation with noninvasive ventilation resulted in a lower incidence of hypoxemia during intubation than preoxygenation with an oxygen mask. (Funded by the U.S. Department of Defense; PREOXI ClinicalTrials.gov number, NCT05267652.)., (Copyright © 2024 Massachusetts Medical Society.)

Introduction: During the COVID-19 pandemic, evidence emerged that immunosuppressed children were less affected by COVID-19 infections compared with immunosuppressed adults. The aim of our study was to investigate how COVID-19 infections affected paediatric kidney transplant recipients (pKTR) in the UK., Methods: Questionnaires regarding COVID-19 infection data and care of pKTR during the COVID-19 pandemic were sent to all 13 UK paediatric nephrology centres examining asymptomatic and symptomatic pKTR with positive COVID-19 PCR testing from 1 April 2020 to 1 December 2021., Results: 63 pKTR who were 3.1 (range 0.1-15) years post-transplantation had COVID-19 infection with positive SARS-CoV-2 PCR RNA. Classical COVID-19 symptoms were present in half of the patients; with atypical presentations including diarrhoea (13%) and lethargy (13%) also noted, while a third of patients were asymptomatic. Eighteen patients (28%) were hospitalised including five asymptomatic patients admitted for other reasons. No patients needed ventilation or intensive care admission, and one patient received supplemental oxygen. There was evidence of acute kidney injury (AKI) in 71% of patients, but no patients needed kidney replacement therapy with haemofiltration or dialysis., Conclusion: We report 10.4% of the UK paediatric renal transplantation population had documented COVID-19 infections with positive SARS-CoV-2 PCR RNA with 28% of those affected requiring hospitalisation. The increased incidence of AKI, particularly after the first wave of the COVID-19 pandemic, was possibly due to increased testing. There was low morbidity and mortality compared with the adult population., Competing Interests: Competing interests: SDM had unpaid roles during COVID-19 pandemic with national COVID-19 working groups of the UK Kidney Association, UK Renal Registry, The British Association for Paediatric Nephrology, National Health Service Blood and Transplant and National Institute for Health and Care Research., (© Author(s) (or their employer(s)) 2024. No commercial re-use. See rights and permissions. Published by BMJ.)

Purpose: To determine the efficacy of an educational intervention on patient adoption and attitudes toward selective laser trabeculoplasty (SLT) as first-line treatment for glaucoma., Methods: This study is a randomized controlled trial. Subjects include 33 patients within 1-year diagnosis of either primary open-angle glaucoma, ocular hypertension, or pseudoexfoliation syndrome. After informed consent, subjects were randomly assigned to a Usual Care or Educational Intervention group. All subjects completed a pre-intervention questionnaire. The Educational Intervention group was shown a slideshow presentation and a 3-min video and given a post-intervention questionnaire. Follow-up examinations were reviewed for 6 months to determine subject completion of SLT, the primary outcome. Secondary outcomes include assessment of attitude toward SLT before and after intervention., Results: Age, gender, and baseline characteristics between the groups did not differ. The Usual Care group had a higher proportion of African Americans (77% vs 31%, p  = 0.04). At 6 months following the intervention, 63% of subjects underwent SLT compared to 35% of Usual Care subjects ( p  = 0.12). Older age was associated with decreased SLT uptake (OR 0.90, 95% CI 0.82-0.99, p  = 0.03). Prior to the intervention, there were no differences in attitudes of both groups regarding SLT therapy. Nineteen percent of Educational Intervention subjects changed positively toward SLT ( p  = 0.08) and 50% scheduled an SLT appointment after intervention ( p  = 0.005)., Conclusions: A slideshow and video-based educational intervention may positively enhance patient adoption of SLT.Clinical trial registration name, number, URL: Educational Intervention to Adopt SLT as First-Line Glaucoma Treatment, NCT03365778, https://clinicaltrials.gov/ct2/show/NCT03365778.