Modelling runoff generation and connectivity for semi-arid hillslopes and small catchments

The processes relating to runoff generation in a semi-arid environment at the hillslope scale are poorly understood. This research considers the amount and origin of water reaching the channel during a storm event using a combination of field experiments and computer simulation techniques. From the field experiments, it was found that the key controls on runoff generation at the point scale are the surface cover of rock fragments, vegetation cover, slope gradient and surface roughness. The effect of land management was found to be greater than geology. The simulation modelling work investigated the controls on runoff generation at the hillslope and small catchment scales. It was found that the storm characteristics are far more important than surface properties in determining the amount of discharge from a slope. The temporal fragmentation of the rainfall was found to control the distribution of flow path lengths and hence the amount of discharge leaving a slope. The key surface controls on the form of the discharge hydrograph are slope length, slope gradient and the hydrological properties at the base of the slope. The origin of runoff was investigated using autonomous software agents able to trace the flow of water through a catchment. This technique is able to give a unique picture of the origin of runoff within a catchment. It was shown that the spatial pattern of the origin of runoff is complex and varies significantly between catchments. This research has shown that there are two key themes in determining the amount of runoff reaching the channel network: the interplay between the distribution of flow path lengths generated during a storm and the distributions of flow lengths to the channel as a function of the landscape. The second theme relates to the importance of the spatial structure of hydrological areas within the landscape

Hypoglycaemic events in patients with type 2 diabetes in the United Kingdom: associations with patient-reported outcomes and self-reported HbA1c

BACKGROUND: One possible barrier to effective diabetes self-management is hypoglycaemia associated with diabetes medication. The current study was conducted to characterize hypoglycaemic events among UK patients with type 2 diabetes (T2D) treated with antihyperglycaemic medications, and assess the relationship between experience of hypoglycaemic events and health outcomes, including glycaemic control, health-related quality of life, impairment to work and non-work activities, treatment satisfaction, adherence to treatment, fear of hypoglycaemia, and healthcare resource use. METHODS: An online survey of 1,329 T2D patients in UK drawn from an opt-in survey panel was conducted in February of 2012 with monthly follow-up questionnaires for five months. Measures included self-reported HbA1c, EQ-5D, Work Productivity and Activity Impairment questionnaire, Diabetes Medication Satisfaction Tool, Morisky medication adherence scale, the Hypoglycaemia Fear Survey (revised), and self-reported healthcare resource use. Comparisons were conducted using t-tests and chi-square tests for continuous and categorical variables, respectively. RESULTS: Baseline comparisons showed that worse HbA1c, greater diabetes-related healthcare resource use, greater fear of hypoglycaemia, and impaired health outcomes were associated with experience of hypoglycaemia in the four weeks prior to baseline. Longitudinal results were similar in direction but differences on few measures were significant. CONCLUSIONS: In real-world UK T2D patients, hypoglycaemia is associated with worse self-reported glycaemic control, behaviours that contribute to worse glycaemic control, and impairment in patient-reported outcomes

Impact of schizophrenia and schizophrenia treatment-related adverse events on quality of life: direct utility elicitation

<b>Objective</b>: To examine the impact of schizophrenia, its treatment and treatment-related adverse events related to antipsychotics, on quality of life from the perspective of schizophrenia patients and laypersons. <b>Methods</b>: Health state descriptions for stable schizophrenia, extra pyramidal symptoms (EPS), hyperprolactinemia, diabetes, weight gain and relapse were developed based on a review of the literature and expert opinion. The quality of life impact of each health state was elicited using a time trade-off instrument administered by interview to 49 stable schizophrenia patients and 75 laypersons. Regression techniques were employed to examine the importance of subject characteristics on health-related utility scores. <b>Results</b>: Patients and laypersons completed the interview in similar times. Stable schizophrenia had the highest mean utility (0.87 and 0.92 for laypersons and patients respectively), while relapse (0.48 and 0.60) had the lowest mean utility. Of the treatment-related adverse events, EPS had the lowest mean utility (0.57 and 0.72, respectively). Age, gender and PANSS score did not influence the utility results independently of health state. On average, patient utilities are 0.077 points higher than utilities derived from laypersons, although the ranking was similar between the two groups. <b>Conclusion</b>: Events associated with schizophrenia and treatment of schizophrenia can bring about a significant detriment in patient quality of life, with relapse having the largest negative impact. Results indicate that patients with stable schizophrenia are less willing to trade years of life to avoid schizophrenia-related symptoms compared to laypersons. Both sets of respondents showed equal ability to complete the questionnaire

Encouraging foot care in people with and without diabetes through narrative communication

In order to minimize risk of infection and potential foot complications, it is recommended that people with and without diabetes check their feet regularly for problems such as cuts, sores, blisters or calluses. Hence, an understanding of how to craft effective messages to encourage people to check their feet is important. Two studies investigated the use of narrative stories to encourage foot problem detection behaviour; Study 1 in a general population sample (N=193), and Study 2 in a sample of people with type 1 or type 2 diabetes (N=129). In both studies participants were randomised to either (a) receive an information sheet written in first-person narrative; (b) the same in non-narrative format; or (c) no information sheet. Changes in weekly detection behaviour was the outcome of interest. In both studies, greater detection behaviour was observed in the narrative message condition vs. non-narrative condition and the non-narrative condition vs. no information condition. Our findings have implications for the design of health messages in delivering effective foot care education to people with and without diabetes, suggesting that narrative information sheets may be more effective than non-narrative information sheets

Well, I wouldn\u27t be any worse off, would I, than I am now? A qualitative study of decision-making, hopes, and realities of adults with type 1 diabetes undergoing islet cell transplantation

BACKGROUND: For selected individuals with type 1 diabetes, pancreatic islet transplantation (IT) prevents recurrent severe hypoglycemia and optimizes glycemia, although ongoing systemic immunosuppression is needed. Our aim was to explore candidates and recipients\u27 expectations of transplantation, their experience of being on the waiting list, and (for recipients) the procedure and life posttransplant. METHODS: Cross-sectional qualitative research design using semistructured interviews with 16 adults (8 pretransplant, 8 posttransplant; from 4 UK centers (n = 13) and 1 Canadian center (n = 3)). Interviews were audio-recorded, transcribed, and underwent inductive thematic analysis. RESULTS: Interviewees were aged (mean ± SD) 52 ± 10 years (range, 30-64); duration of diabetes, 36 ± 9 years (range, 21-56); 12 (75%) were women. Narrative accounts centered on expectations, hopes, and realities; decision-making; waiting and uncertainty; the procedure, hospital stay, and follow-up. Expected benefits included fewer severe hypoglycemic episodes, reduced need for insulin, preventing onset/progression of complications and improved psychological well-being. These were realized for most, at least in the short term. Most interviewees described well-informed, shared decision-making with clinicians and family, and managing their expectations. Although life "on the list" could be stressful, and immunosuppressant side effects were severe, interviewees reported "no regrets." Posttransplant, interviewees experienced increased confidence, through freedom from hypoglycemia and regained glycemic control, which tempered any disappointment about continued reliance on insulin. Most viewed their transplant as a success, though several reflected upon setbacks and hidden hopes for becoming "insulin-free." CONCLUSIONS: Independently undertaken interviews demonstrated realistic and balanced expectations of IT and indicate how to optimize the process and support for future IT candidates

Robust estimation of bacterial cell count from optical density

Optical density (OD) is widely used to estimate the density of cells in liquid culture, but cannot be compared between instruments without a standardized calibration protocol and is challenging to relate to actual cell count. We address this with an interlaboratory study comparing three simple, low-cost, and highly accessible OD calibration protocols across 244 laboratories, applied to eight strains of constitutive GFP-expressing E. coli. Based on our results, we recommend calibrating OD to estimated cell count using serial dilution of silica microspheres, which produces highly precise calibration (95.5% of residuals <1.2-fold), is easily assessed for quality control, also assesses instrument effective linear range, and can be combined with fluorescence calibration to obtain units of Molecules of Equivalent Fluorescein (MEFL) per cell, allowing direct comparison and data fusion with flow cytometry measurements: in our study, fluorescence per cell measurements showed only a 1.07-fold mean difference between plate reader and flow cytometry data

Network intrusion response using deep reinforcement learning in an aircraft IT-OT scenario

This paper presents an intrusion response system created using deep reinforcement learning, trained within an emulation environment. The emulation environment aims to represent a networked IT-OT system found within an aircraft. The goal of this paper’s experimentation is to explore training to defend against an attack chain in a way that more closely resembles a real network than that of current work. This has been achieved through the novel inclusion of open-source intrusion detection systems which feed default alert information to the response system. Experiments demonstrate the ability of the reinforcement learning agent to converge towards an effective response policy for defending the system against a multi-stage attack while minimizing disruption to do so