Machine Learning in Falls Prediction; A cognition-based predictor of falls for the acute neurological in-patient population

Background Information: Falls are associated with high direct and indirect costs, and significant morbidity and mortality for patients. Pathological falls are usually a result of a compromised motor system, and/or cognition. Very little research has been conducted on predicting falls based on this premise. Aims: To demonstrate that cognitive and motor tests can be used to create a robust predictive tool for falls. Methods: Three tests of attention and executive function (Stroop, Trail Making, and Semantic Fluency), a measure of physical function (Walk-12), a series of questions (concerning recent falls, surgery and physical function) and demographic information were collected from a cohort of 323 patients at a tertiary neurological center. The principal outcome was a fall during the in-patient stay (n = 54). Data-driven, predictive modelling was employed to identify the statistical modelling strategies which are most accurate in predicting falls, and which yield the most parsimonious models of clinical relevance. Results: The Trail test was identified as the best predictor of falls. Moreover, addition of any others variables, to the results of the Trail test did not improve the prediction (Wilcoxon signed-rank p < .001). The best statistical strategy for predicting falls was the random forest (Wilcoxon signed-rank p < .001), based solely on results of the Trail test. Tuning of the model results in the following optimized values: 68% (+- 7.7) sensitivity, 90% (+- 2.3) specificity, with a positive predictive value of 60%, when the relevant data is available. Conclusion: Predictive modelling has identified a simple yet powerful machine learning prediction strategy based on a single clinical test, the Trail test. Predictive evaluation shows this strategy to be robust, suggesting predictive modelling and machine learning as the standard for future predictive tools

Comparing perceived clarity of information on overdiagnosis used for breast and prostate cancer screening in England: an experimental survey.

OBJECTIVES: 'Overdiagnosis', detection of disease that would never have caused symptoms or death, is a public health concern due to possible psychological and physical harm but little is known about how best to explain it. This study evaluated public perceptions of widely used information on the concept to identify scope for improving communication methods. DESIGN: Experimental survey carried out by a market research company via face-to-face computer-assisted interviews. SETTING: Interviews took place in participants' homes. PARTICIPANTS: 2111 members of the general public in England aged 18-70 years began the survey; 1616 were eligible for analysis. National representativeness was sought via demographic quota sampling. INTERVENTIONS: Participants were allocated at random to receive a brief description of overdiagnosis derived from written information used by either the NHS Breast Screening Programme or the prostate cancer screening equivalent. PRIMARY AND SECONDARY OUTCOME MEASURES: The primary outcome was how clear the information was perceived to be (extremely/very clear vs less clear). Other measures included previous exposure to screening information, decision-making styles and demographic characteristics (eg, education). Binary logistic regression was used to assess predictors of perceived clarity. RESULTS: Overdiagnosis information from the BSP was more likely to be rated as more clear compared with the prostate screening equivalent (adjusted OR: 1.43, 95% CI 1.17 to 1.75; p=0.001). Participants were more likely to perceive the information as more clear if they had previously encountered similar information (OR: 1.77, 1.40 to 2.23; p<0.0005) or a screening leaflet (OR: 1.35, 1.04 to 1.74; p=0.024) or had a more 'rational' decision-making style (OR: 1.06, 1.02 to 1.11; p=0.009). CONCLUSIONS: Overdiagnosis information from breast screening may be a useful template for communicating the concept more generally (eg, via organised campaigns). However, this information may be less well-suited to individuals who are less inclined to consider risks and benefits during decision-making

Beyond solvent exclusion: i-Motif detecting capability and an alternative DNA light-switching mechanism in a ruthenium(II) polypyridyl complex

Cytosine-rich DNA can fold into secondary structures known as i-motifs. Mounting experimental evidence suggests that these non-canonical nucleic acid structures form in vivo and play biological roles. However, to date, there are no optical probes able to identify i-motif in the presence of other types of DNA. Herein, we report for the first time the interactions between the three isomers of [Ru(bqp)2]2+ with i-motif, G-quadruplex, and double-stranded DNA. Each isomer has vastly different light-switching properties: mer is “on”, trans is “off”, and cis switches from “off” to “on” in the presence of all types of DNA. Using emission lifetime measurements, we show the potential of cis to light up and identify i-motif, even when other DNA structures are present using a sequence from the promoter region of the death-associated protein (DAP). Moreover, separated cis enantiomers revealed Λ-cis to have a preference for the i-motif, whereas Δ-cis has a preference for double-helical DNA. Finally, we propose a previously unreported light-switching mechanism that originates from steric compression and electronic effects in a tight binding site, as opposed to solvent exclusion. Our work suggests that many published non-emissive Ru complexes could potentially switch on in the presence biological targets with suitable binding sites, opening up a plethora of opportunity in the detection of biological molecules

The New Zealand rugby injury and performance project. IV. Anthropometric and physical performance comparisons between positional categories of senior A rugby players.

OBJECTIVE--To describe the anthropometric and physical performance characteristics of a sample of senior A club rugby players and to highlight differences between the positional categories of the players within the forwards and backs. METHODS--94 senior A male rugby players were assessed on a number of anthropometric and physical performance assessments. The forwards were categorised into props, hookers, locks, and loose forwards. Backs were categorised into inside, midfield, and outside backs. Categories within the forwards were compared with each other, as were the categories within the backs. RESULTS--The anthropometric characteristics of forwards differed significantly between positional categories. Front row forwards (props and hookers) possessed highly endo-mesomorphic somatotypes, and typically rated very low for ectomorphy. Props possessed greater body mass than hookers. Locks and loose forwards were taller than the front row forwards. In terms of physical performance fewer differences were observed. Hookers performed better than props on an aerobic assessment. Locks and loose forwards were faster than the front row forwards on a 30 m sprint from a running start. The inside backs were shorter and lighter than the midfield and outside backs. CONCLUSIONS--The combination of anthropometric characteristics and physical performance attributes observed allows players to best meet the demands imposed on them by their position

Reusable Agena study. Volume 2: Technical

The application of the existing Agena vehicle as a reusable upper stage for the space shuttle is discussed. The primary objective of the study is to define those changes to the Agena required for it to function in the reusable mode in the 100 percent capture of the NASA-DOD mission model. This 100 percent capture is achieved without use of kick motors or stages by simply increasing the Agena propellant load by using optional strap-on-tanks. The required shuttle support equipment, launch and flight operations techniques, development program, and cost package are also defined

Identification of multiple genomic DNA sequences which form i-motif structures at neutral pH

i-Motifs are alternative DNA secondary structures formed in cytosine-rich sequences. Particular examples of these structures, traditionally assumed to be stable only at acidic pH, have been found to form under near-physiological conditions. To determine the potential impact of these structures on physiological processes, investigation of sequences with the capacity to fold under physiological conditions is required. Here we describe a systematic study of cytosine-rich DNA sequences, with varying numbers of consecutive cytosines, to gain insights into i-motif DNA sequence and structure stability. i-Motif formation was assessed using ultraviolet spectroscopy, circular dichroism and native gel electrophoresis. We found that increasing cytosine tract lengths resulted in increased thermal stability; sequences with at least five cytosines per tract folded into i-motif at room temperature and neutral pH. Using these results, we postulated a folding rule for i-motif formation, analogous to (but different from) that for G-quadruplexes. This indicated that thousands of cytosine-rich sequences in the human genome may fold into i-motif structures under physiological conditions. Many of these were found in locations where structure formation is likely to influence gene expression. Characterization of a selection of these identified i-motif forming sequences uncovered 17 genomic i-motif forming sequence examples which were stable at neutral pH

Identification of multiple genomic DNA sequences which form i-motif structures at neutral pH

i-Motifs are alternative DNA secondary structures formed in cytosine-rich sequences. Particular examples of these structures, traditionally assumed to be stable only at acidic pH, have been found to form under near-physiological conditions. To determine the potential impact of these structures on physiological processes, investigation of sequences with the capacity to fold under physiological conditions is required. Here we describe a systematic study of cytosine-rich DNA sequences, with varying numbers of consecutive cytosines, to gain insights into i-motif DNA sequence and structure stability. i-Motif formation was assessed using ultraviolet spectroscopy, circular dichroism and native gel electrophoresis. We found that increasing cytosine tract lengths resulted in increased thermal stability; sequences with at least five cytosines per tract folded into i-motif at room temperature and neutral pH. Using these results, we postulated a folding rule for i-motif formation, analogous to (but different from) that for G-quadruplexes. This indicated that thousands of cytosine-rich sequences in the human genome may fold into i-motif structures under physiological conditions. Many of these were found in locations where structure formation is likely to influence gene expression. Characterization of a selection of these identified i-motif forming sequences uncovered 17 genomic i-motif forming sequence examples which were stable at neutral pH

Microplastics in the Antarctic marine system: An emerging area of research

It was thought that the Southern Ocean was relatively free of microplastic contamination; however, recent studies and citizen science projects in the Southern Ocean have reported microplastics in deep-sea sediments and surface waters. Here we reviewed available information on microplastics (including macroplastics as a source of microplastics) in the Southern Ocean. We estimated primary microplastic concentrations from personal care products and laundry, and identified potential sources and routes of transmission into the region. Estimates showed the levels of microplastic pollution released into the region from ships and scientific research stations were likely to be negligible at the scale of the Southern Ocean, but may be significant on a local scale. This was demonstrated by the detection of the first microplastics in shallow benthic sediments close to a number of research stations on King George Island. Furthermore, our predictions of primary microplastic concentrations from local sources were five orders of magnitude lower than levels reported in published sampling surveys (assuming an even dispersal at the ocean surface). Sea surface transfer from lower latitudes may contribute, at an as yet unknown level, to Southern Ocean plastic concentrations. Acknowledging the lack of data describing microplastic origins, concentrations, distribution and impacts in the Southern Ocean, we highlight the urgent need for research, and call for routine, standardised monitoring in the Antarctic marine system

Women's interpretation of and responses to potential gynaecological cancer symptoms: a qualitative interview study

OBJECTIVE: To explore women's experiences of symptoms potentially indicative of gynaecological cancer in a community-based sample without imposing a cancer perspective. DESIGN: A qualitative interview study with thematic analysis of transcripts. PARTICIPANTS: 26 women aged ≥30 years, who had experienced a symptom that might indicate gynaecological cancer in the past 3 months, were recruited using a screening questionnaire distributed online and in community settings. SETTING: London, UK. RESULTS: Women attributed gynaecological symptoms to existing illnesses/conditions or considered themselves to be predisposed to them, either through their 'genes' or previous personal experience. Normalising symptoms by attributing them to demographic characteristics (e.g., age, sex) was common, as was considering them a side effect of hormonal contraception. When women raised cancer as a possible cause, they often dismissed it as unlikely. Responses to symptoms included self-management (e.g., self-medicating, making lifestyle changes), adopting a 'lay system of care', or consulting a healthcare professional. Triggers to help-seeking included persistent, painful or debilitating symptoms, concern about symptom seriousness, and feeling that help-seeking was legitimised. Barriers to help-seeking included lack of concern, vague symptoms, unusual symptom location, competing time demands, previous negative experiences with the healthcare system, and not wanting to be perceived as a time-waster. CONCLUSIONS: Attributions of symptoms potentially indicative of a gynaecological cancer were varied, but most often involved women fitting symptoms into their expectations of what was 'normal'. Normalising acted as a barrier to seeking help from a healthcare professional, alongside competing time demands and negative attitudes towards help-seeking. These barriers may lead to later diagnosis and poorer cancer survival. Our findings could be used to inform the development of interventions to encourage appropriate help-seeking