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Postnatal mental health is often assessed using self-assessment questionnaires in epidemiologic research. Differences in response style, influenced by language, culture, and experience, may mean that the same response may not have the same meaning in different settings. These differences need to be identified and accounted for in cross-cultural comparisons. Here we describe the development and application of anchoring vignettes to investigate the cross-cultural functioning of the Edinburgh Postnatal Depression Scale (EPDS) in urban community samples in India (n  = 549) and the United Kingdom (n  = 828), alongside a UK calibration sample (n  = 226). Participants completed the EPDS and anchoring vignettes when their children were 12–24 months old. In an unadjusted item-response theory model, UK mothers reported higher depressive symptoms than Indian mothers (d  = 0.48, 95% confidence interval: 0.358, 0.599). Following adjustment for differences in response style, these positions were reversed (d  = −0.25, 95% confidence interval: −0.391, −0.103). Response styles vary between India and the United Kingdom, indicating a need to take these differences into account when making cross-cultural comparisons. Anchoring vignettes offer a valid and feasible method for global data harmonization. [ABSTRACT FROM AUTHOR]

Objective The purpose of this study was to develop and externally validate multivariable prediction models for future pain intensity outcomes to inform targeted interventions for patients with neck or low back pain in primary care settings. Methods Model development data were obtained from a group of 679 adults with neck or low back pain who consulted a participating United Kingdom general practice. Predictors included self-report items regarding pain severity and impact from the STarT MSK Tool. Pain intensity at 2 and 6 months was modeled separately for continuous and dichotomized outcomes using linear and logistic regression, respectively. External validation of all models was conducted in a separate group of 586 patients recruited from a similar population with patients' predictor information collected both at point of consultation and 2 to 4 weeks later using self-report questionnaires. Calibration and discrimination of the models were assessed separately using STarT MSK Tool data from both time points to assess differences in predictive performance. Results Pain intensity and patients reporting their condition would last a long time contributed most to predictions of future pain intensity conditional on other variables. On external validation, models were reasonably well calibrated on average when using tool measurements taken 2 to 4 weeks after consultation (calibration slope = 0.848 [95% CI = 0.767 to 0.928] for 2-month pain intensity score), but performance was poor using point-of-consultation tool data (calibration slope for 2-month pain intensity score of 0.650 [95% CI = 0.549 to 0.750]). Conclusion Model predictive accuracy was good when predictors were measured 2 to 4 weeks after primary care consultation, but poor when measured at the point of consultation. Future research will explore whether additional, nonmodifiable predictors improve point-of-consultation predictive performance. Impact External validation demonstrated that these individualized prediction models were not sufficiently accurate to recommend their use in clinical practice. Further research is required to improve performance through inclusion of additional nonmodifiable risk factors. [ABSTRACT FROM AUTHOR]

Aim: This study was aimed to: (1) compare raw triaxial acceleration data from GENEActiv (GA) and ActiGraph GT3X+ (AG) placed on the non‐dominant wrist; (2) compare AG placed on the non‐dominant and dominant wrist, and waist; (3) derive brand‐ and placement‐specific absolute intensity thresholds for inactive and sedentary time, and physical activity intensity in adults. Methods: Eighty‐six adults (44 men; 34.6 ± 10.8 years) performed nine activities while simultaneously wearing GA and AG on wrist and waist. Acceleration (in gravitational equivalent units; mg) was compared with oxygen uptake (measured with indirect calorimetry). Results: Increases in acceleration mirrored increases in intensity of activities, regardless of device brand and placement. Differences in acceleration between GA and AG worn at the non‐dominant wrist were small but tended to be high at lower intensity activities. Thresholds for differentiating inactivity (<1.5 MET) from activity (≥1.5 MET) ranged from 25 mg (AG non‐dominant wrist; sensitivity 93%, specificity 95%) to 40 mg (AG waist; sensitivity 78%, specificity 100%). For moderate intensity (≥3 METs), thresholds ranged from 65 mg (AG waist; sensitivity 96%, specificity 94%) to 92 mg (GA non‐dominant; sensitivity 93%, specificity 98%); vigorous intensity (≥6 METs) thresholds ranged from 190 mg (AG waist; sensitivity 82%, specificity 92%) to 283 mg (GA non‐dominant; sensitivity 93%, specificity 98%). Conclusion: Raw triaxial acceleration outputs from two widely used accelerometer brands may have limited comparability in low intensity activities. Thresholds derived in this study can be utilized in adults to reasonably classify movement behaviors into categories of intensity. [ABSTRACT FROM AUTHOR]

The Research Excellence Framework (REF) is a UK policy tool for distributing government funding and an important indicator of the academic status of a UK university. The legitimacy of the policy comes from peers' consensus on what academic quality is. We are interested in how the REF enables this funding distribution by determining the academic quality of a broad array of different forms of research through a single peer-review process. As they search for academic quality that is contingent to a specific epistemology and requires more time than the REF allows, how do academics agree to agree, and within constraints of a given timeframe? Interviews with REF panellists and their accounts of the process lead us to suggest that the consensus is enacted by setting up a situation: the mechanics of the REF with its practices of benchmarking, scoring, calibrating, and normalizing. This situation sets the boundaries of reviewing and, in doing so, propels peers to shift from assessment contingent on epistemic commitments to evaluation on a single scale. We argue that this shift renders academic quality distinct from scientific or epistemic quality. [ABSTRACT FROM AUTHOR]

The United Kingdom's Living Costs and Food (LCF) Survey has a relatively small sample size but produces estimates which are widely used, notably as a key input to the calculation of weights for consumer price indices. There has been a recent call for the use of additional data sources to improve the estimates from the LCF. Since some LCF variables are shared with the much larger Labour Force Survey (LFS), we investigate combining data from these surveys using composite calibration to improve the precision of estimates from the LCF. We undertake model selection to choose a suitable set of common variables for the composite calibration using the effect on the estimated variances for national and regional totals of important LCF variables. The variances of estimates for common variables are reduced to around 5 percent of their original size. Variances of national estimates are reduced (across several quarters) by around 10 percent for expenditure and 25 percent for income; these are the variables of primary interest in the LCF. Reductions in the variances of regional estimates vary more but are mostly large when using common variables at the regional level in the composite calibration. The composite calibration also makes the LCF estimates for employment status almost consistent with the outputs of the LFS, which is an important property for users of the statistics. A novel alternative method for variance estimation, using stored information produced by the composite calibration, is also presented. [ABSTRACT FROM AUTHOR]

Background: The Surgical Outcome Risk Tool (SORT) was derived and validated in the UK to improve preoperative prediction of postoperative risk. The aim of this study was to validate the SORT in a European mixed-case surgical population outside of the UK. Methods: The study included patients aged at least 18 years with ASA Physical Status (ASA-PS) grades I-V who underwent non-cardiac surgery at four tertiary hospitals in Sweden between November 2015 and February 2016. Exclusion criteria were surgery under local anaesthesia and missing data on the SORT predictors (ASA-PS, surgical urgency, high-risk surgery, surgical severity, malignancy, age over 65 years). The outcome was 30-day mortality. Discrimination and calibration of the SORT were assessed using area under the receiver operating curve (AUROC) statistics and calibration plots. A sensitivity analysis was done in a high-risk subgroup (ASAPS III or higher; surgical complexity major to Xmajor according to the SORT; gastrointestinal, orthopaedic, urogenital/obstetric surgery; and age at least 18 years). Results: The validation cohort included 17 965 patients; median age was 58 (i.q.r. 40-70) years, 43.2 per cent were men, and the mortality rate at 30 days was 1.6 per cent. The SORT had excellent discrimination, with an AUROC of 0.91 (95 per cent c.i. 0.89 to 0.92), and good calibration. The high-risk subgroup (1807 patients) had a 30-day mortality rate of 5.6 per cent; in the sensitivity analysis, the SORT had good discrimination, with an AUROC of 0.79 (0.74 to 0.83), and calibration remained good. Conclusion: The estimates of the original the SORT for prediction of 30-day mortality were valid and reliable in a mixed-case surgical population in a non-UK European setting. [ABSTRACT FROM AUTHOR]

Calibration is an important source of variability in liquid chromatography mass spectrometry (LC-MS) methods for insulin-like growth factor 1 (IGF-1). This study investigated the impact of different calibrator matrices on IGF-1 measurements by LC-MS. Moreover, the comparability of immunoassays and LC-MS was assessed. Calibrators from 12.5 to 2009 ng/ml were prepared by spiking WHO international Standard (ID 02/254 NIBSC, UK) into the following matrices: native human plasma, fresh charcoal-treated human plasma (FCTHP), old charcoal-treated human plasma, deionized water, bovine serum albumin (BSA), and rat plasma (RP). A validated in-house LC-MS method was calibrated repeatedly with these calibrators. Then, serum samples from 197 growth hormone excess and deficiency patients were analysed with each calibration. The seven calibration curves had different slopes leading to markedly different patient results. The largest differences in IGF-1 concentration from the median (interquartile range) was observed with the calibrator in water and the calibrator in RP (336.4 [279.6–417.0] vs. 112.5 [71.2–171.2], p < 0.001). The smallest difference was observed with calibrators in FCTHP and BSA (141.8 [102.0–198.5] vs. 127.9 [86.9–186.0], p < 0.049). Compared to LC-MS with calibrators in FCTHP, immunoassays showed relevant proportional bias (range: −43% to −68%), constant bias (range: 22.84 to 57.29 ng/ml) and pronounced scatter. Comparing the immunoassays with each other revealed proportional bias of up to 24%. The calibrator matrix is critical for the measurement of IGF-1 by LC-MS. Regardless of the calibrator matrix, LC-MS shows poor agreement with immunoassays. Also, the agreement between different immunoassays is variable. [ABSTRACT FROM AUTHOR]

Whole-genome sequencing (WGS) is the gold standard for fully characterizing genetic variation but is still prohibitively expensive for large samples. To reduce costs, many studies sequence only a subset of individuals or genomic regions, and genotype imputation is used to infer genotypes for the remaining individuals or regions without sequencing data. However, not all variants can be well imputed, and the current state-of-the-art imputation quality metric, denoted as standard Rsq, is poorly calibrated for lower-frequency variants. Here, we propose MagicalRsq, a machine-learning-based method that integrates variant-level imputation and population genetics statistics, to provide a better calibrated imputation quality metric. Leveraging WGS data from the Cystic Fibrosis Genome Project (CFGP), and whole-exome sequence data from UK BioBank (UKB), we performed comprehensive experiments to evaluate the performance of MagicalRsq compared to standard Rsq for partially sequenced studies. We found that MagicalRsq aligns better with true R2 than standard Rsq in almost every situation evaluated, for both European and African ancestry samples. For example, when applying models trained from 1,992 CFGP sequenced samples to an independent 3,103 samples with no sequencing but TOPMed imputation from array genotypes, MagicalRsq, compared to standard Rsq, achieved net gains of 1.4 million rare, 117k low-frequency, and 18k common variants, where net gains were gained numbers of correctly distinguished variants by MagicalRsq over standard Rsq. MagicalRsq can serve as an improved post-imputation quality metric and will benefit downstream analysis by better distinguishing well-imputed variants from those poorly imputed. MagicalRsq is freely available on GitHub. [Display omitted] Ever-growing reference panels allow imputation of huge number (∼108) of lower-frequency variants. However, not all variants can be well imputed and standard imputation quality metric poorly reflects true imputation quality, particularly for uncommon variants. We present MagicalRsq, a machine-learning-based and better calibrated post-imputation quality metric, that can rescue 105–106 variants. [ABSTRACT FROM AUTHOR]

Accurate precipitation estimation with weather radars is essential for hydrological and meteorological applications. The differential reflectivity (ZDR) is a crucial weather radar measurement that helps to improve quantitative precipitation estimates using polarimetric weather radars. However, a system bias between the horizontal and vertical channels generated by the radar produces an offset in ZDR. Existing methods to calibrate ZDR measurements rely on the intrinsic values of the ZDR of natural targets (e.g. drizzle or dry snow) collected at high elevation angles (e.g. higher than 40 ∘ or even at 90 ∘), in which ZDR values close to 0 dB are expected. However, not all weather radar systems can scan at such high elevation angles or point the antenna vertically to collect precipitation measurements passing overhead. Therefore, there is a need to develop new methods to calibrate ZDR measurements using lower-elevation scans. In this work, we present and analyse a novel method for correcting and monitoring the ZDR offset using quasi-vertical profiles computed from scans collected at 9 ∘ elevations. The method is applied to radar data collected through 1 year of precipitation events by two operational C-band polarimetric weather radars in the UK. The proposed method shows a relative error of 0.1 dB when evaluated against the traditional approach based on ZDR measurements collected at 90 ∘ elevations. Additionally, the method is independently assessed using disdrometers located near the radar sites. The results showed a reasonable agreement between disdrometer-derived and radar-calibrated ZDR measurements. [ABSTRACT FROM AUTHOR]

Visuospatial working memory (VSWM) is essential to human cognitive abilities and is associated with important life outcomes such as academic performance. Recently, a number of reliable measures of VSWM have been developed to help understand psychological processes and for practical use in education. We sought to extend this work using Item Response Theory (IRT) and Computerised Adaptive Testing (CAT) frameworks to construct, calibrate and validate a new adaptive, computerised, and open-source VSWM test. We aimed to overcome the limitations of previous instruments and provide researchers with a valid and freely available VSWM measurement tool. The Jack and Jill (JaJ) VSWM task was constructed using explanatory item response modelling of data from a sample of the general adult population (Study 1, N = 244) in the UK and US. Subsequently, a static version of the task was tested for validity and reliability using a sample of adults from the UK and Australia (Study 2, N = 148) and a sample of Russian adolescents (Study 3, N = 263). Finally, the adaptive version of the JaJ task was implemented on the basis of the underlying IRT model and evaluated with another sample of Russian adolescents (Study 4, N = 239). JaJ showed sufficient internal consistency and concurrent validity as indicated by significant and substantial correlations with established measures of working memory, spatial ability, non-verbal intelligence, and academic achievement. The findings suggest that JaJ is an efficient and reliable measure of VSWM from adolescent to adult age. [ABSTRACT FROM AUTHOR]

Statistical models for clinical risk prediction are often derived using data from primary care databases; however, they are frequently used outside of clinical settings. The use of prediction models in epidemiological studies without external validation may lead to inaccurate results. We use the example of applying the QRISK3 model to data from the United Kingdom (UK) Biobank study to illustrate the challenges and provide suggestions for future authors. The QRISK3 model is recommended by the National Institute for Health and Care Excellence (NICE) as a tool to aid cardiovascular risk prediction in English and Welsh primary care patients aged between 40 and 74. QRISK3 has not been externally validated for use in studies where data is collected for more general scientific purposes, including the UK Biobank study. This lack of external validation is important as the QRISK3 scores of participants in UK Biobank have been used and reported in several publications. This paper outlines: (i) how various publications have used QRISK3 on UK Biobank data and (ii) the ways that the lack of external validation may affect the conclusions from these publications. We then propose potential solutions for addressing these challenges; for example, model recalibration and considering alternative models, for the application of traditional statistical models such as QRISK3, in cohorts without external validation. [ABSTRACT FROM AUTHOR]

In recent years, there has been rapid growth in demand for precision grade micro-electromechanical system microphones (MEMSMs). While new applications are increasingly demanding in terms of MEMSM performance, research and development of the technology is thus far keeping pace. To calibrate all these new MEMSMs, a reliable and cost-efficient method for bulk calibration of MEMSMs is urgently required. This paper describes a pilot version of such a method, carried out at the United Kingdom's National Physical Laboratory. The method was intended for use by MEMSM manufacturers themselves for bulk calibration. It may also be usable by manufacturers of devices that incorporate multiple MEMSMs for bulk calibration of these MEMSMs, provided that they are detachable from the devices' circuit-boards. The uncertainty of the method has been compared to that of the coupler comparison calibration which is a technique for acoustic pressure calibration of precision microphones. It is concluded that the pilot method is promising as the basis of a method for the bulk calibration of precision MEMSMs. [ABSTRACT FROM AUTHOR]

Brain–computer interface (BCI)-controlled assistive robotic systems have been developed with increasing success with the aim to rehabilitation of patients after brain injury to increase independence and quality of life. While such systems may use surgically implanted invasive sensors, non-invasive alternatives can be better suited due to the ease of use, reduced cost, improvements in accuracy and reliability with the advancement of the technology and practicality of use. The consumer-grade BCI devices are often capable of integrating multiple types of signals, including Electroencephalogram (EEG) and Electromyogram (EMG) signals. This paper summarizes the development of a portable and cost-efficient BCI-controlled assistive technology using a non-invasive BCI headset "OpenBCI" and an open source robotic arm, U-Arm, to accomplish tasks related to rehabilitation, such as access to resources, adaptability or home use. The resulting system used a combination of EEG and EMG sensor readings to control the arm. To avoid risks of injury while the device is being used in clinical settings, appropriate measures were incorporated into the software control of the arm. A short survey was used following the system usability scale (SUS), to measure the usability of the technology to be trialed in clinical settings. From the experimental results, it was found that EMG is a very reliable method for assistive technology control, provided that the user specific EMG calibration is done. With the EEG, even though the results were promising, due to insufficient detection of the signal, the controller was not adequate to be used within a neurorehabilitation environment. The survey indicated that the usability of the system is not a barrier for moving the system into clinical trials. For the rehabilitation of patients suffering from neurological disabilities (particularly those suffering from varying degrees of paralysis), it is necessary to develop technology that bypasses the limitations of their condition. For example, if a patient is unable to walk due to the unresponsiveness in their motor neurons, technology can be developed that used an alternate input to move an exoskeleton, which enables the patient to walk again with the assistance of the exoskeleton. This research focuses on neuro-rehabilitation within the framework of the NHS at the Kent and Canterbury Hospital in UK. The hospital currently does not have any system in place for self-driven rehabilitation and instead relies on traditional rehabilitation methods through assistance from physicians and exercise regimens to maintain muscle movement. This paper summarises the development of a portable and cost-efficient BCI controlled assistive technology using a non-invasive BCI headset "OpenBCI" and an open source robotic arm, U-Arm, to accomplish tasks related to rehabilitation, such as access to resources, adaptability or home use. The resulting system used a combination of EEG and EMG sensor readings to control the arm, which could perform a number of different tasks such as picking/placing objects or assist users in eating. [ABSTRACT FROM AUTHOR]

In this short intervention we report on work in progress by Advance HE (formerly the Higher Education Academy) in collaboration with professional bodies such as the RGS‐IBG, which seeks to respond to public concerns about "grade inflation" in relation to degree outcomes. We present an updated analysis of degree outcomes in UK geography for 2010–2016 showing a strong correlation between average A‐level points score on entry and the proportion of good degrees awarded by UK geography departments. We then go on to report on the results of pilot training activities within the discipline to increase the use of social calibration techniques as a means of providing transparent assurance about the high quality of assessment practices. We conclude that there is good reason to engage positively and actively with the public debate about academic standards and we make the case for regular social calibration exercises to share marking practices across multiple institutions as a potential means of ensuring consistency, reliability and clarity in academic standards. [ABSTRACT FROM AUTHOR]

Background: UK Biobank is a large prospective cohort study containing accelerometer-based physical activity data with strong validity collected from 100,000 participants approximately 5 years after baseline. In contrast, the main cohort has multiple self-reported physical behaviours from > 500,000 participants with longer follow-up time, offering several epidemiological advantages. However, questionnaire methods typically suffer from greater measurement error, and at present there is no tested method for combining these diverse self-reported data to more comprehensively assess the overall dose of physical activity. This study aimed to use the accelerometry sub-cohort to calibrate the self-reported behavioural variables to produce a harmonised estimate of physical activity energy expenditure, and subsequently examine its reliability, validity, and associations with disease outcomes. Methods: We calibrated 14 self-reported behavioural variables from the UK Biobank main cohort using the wrist accelerometry sub-cohort (n = 93,425), and used published equations to estimate physical activity energy expenditure (PAEESR). For comparison, we estimated physical activity based on the scoring criteria of the International Physical Activity Questionnaire, and by summing variables for occupational and leisure-time physical activity with no calibration. Test-retest reliability was assessed using data from the UK Biobank repeat assessment (n = 18,905) collected a mean of 4.3 years after baseline. Validity was assessed in an independent validation study (n = 98) with estimates based on doubly labelled water (PAEEDLW). In the main UK Biobank cohort (n = 374,352), Cox regression was used to estimate associations between PAEESR and fatal and non-fatal outcomes including all-cause, cardiovascular diseases, respiratory diseases, and cancers. Results: PAEESR explained 27% variance in gold-standard PAEEDLW estimates, with no mean bias. However, error was strongly correlated with PAEEDLW (r = −.98; p < 0.001), and PAEESR had narrower range than the criterion. Test-retest reliability (Λ =.67) and relative validity (Spearman =.52) of PAEESR outperformed two common approaches for processing self-report data with no calibration. Predictive validity was demonstrated by associations with morbidity and mortality, e.g. 14% (95%CI: 11–17%) lower mortality for individuals meeting lower physical activity guidelines. Conclusions: The PAEESR variable has good reliability and validity for ranking individuals, with no mean bias but correlated error at individual-level. PAEESR outperformed uncalibrated estimates and showed stronger inverse associations with disease outcomes. [ABSTRACT FROM AUTHOR]

Current intermittently scanned continuous glucose monitoring (isCGM) devices do not allow calibration and require confirmatory self-monitored blood glucose (SMBG) under specific defined conditions. The overall time spent in an SMBG-indicated state while using isCGM has not been reported in the existing literature. We present the time spent in an SMBG-indicated state and the daily number of transitions to an SMBG-indicated state during isCGM use in a high-risk cohort of adults with type 1 diabetes. This is a post hoc analysis of participants randomized to isCGM as part of a clinical study. The percentage of values meeting one or more of the criteria for SMBG testing (hours per day) and the number of transitions to an SMBG-indicated state per day were calculated according to the manufacturer's label in the United Kingdom. Complete data sets for 20 participants on isCGM for 8 weeks were included in the analysis. Participants spent a mean (SD) of 5.61 (1.81) h/day in an SMBG-indicated state and there were 5.43 (1.42) transitions to an SMBG-indicated state per day while using isCGM. These findings have important implications for cost-effectiveness and for decision-making around insulin dose calculations and driving. Our findings emphasize the need for continued SMBG testing among people at high risk of hypoglycemia who use isCGM. Cost-effectiveness analyses for isCGM may require revision. [ABSTRACT FROM AUTHOR]

The hydrological response is changeable for catchments with hydro-meteorological variations, which is neglected by the traditional calibration approach through using time-invariant parameters. This study aims to reproduce the variation of hydrological responses by allowing parameters to vary over clusters with hydro-meteorological similarities. The Fuzzy C-means algorithm is used to partition one-month periods into temperature-based and rainfall-based clusters. One-month periods are also classified based on seasons and random numbers for comparison. This study is carried out in three catchments in the UK, using the IHACRES rainfall-runoff model. Results show when using time-varying parameters to account for the variation of hydrological processes, it is important to identify the key factors that cause the change of hydrological responses, and the selection of the time-varying parameters should correspond to the identified key factors. In the study sites, temperature plays a more important role in controlling the change of hydrological responses than rainfall. It is found that the number of clusters has an effect on model performance, model performances for calibration period become better with the increase of cluster number; however, the increase of model complexity leads to poor predictive capabilities due to overfitting. It is important to select the appropriate number of clusters to achieve a balance between model complexity and model performance. [ABSTRACT FROM AUTHOR]

Ensemble weather forecasts often under‐represent uncertainty, leading to overconfidence in their predictions. Multi‐model forecasts combining several individual ensembles have been shown to display greater skill than single‐ensemble forecasts in predicting temperatures, but tend to retain some bias in their joint predictions. Established postprocessing techniques are able to correct bias and calibration issues in univariate forecasts, but are generally not designed to handle multivariate forecasts (of several variables or at several locations, say). We propose a flexible multivariate Bayesian postprocessing framework, based on a directed acyclic graph representing the relationships between the ensembles and the observed weather. The posterior forecast is inferred from available ensemble forecasts and an estimate of the shared discrepancy, obtained from a collection of past forecast–observation pairs. We also propose a novel approach to selecting an appropriate training set for estimation of the required correction, using synoptic‐scale analogues to obtain a regime‐dependent estimate of the adjustment. The proposed technique is applied to forecasts of surface temperature over the UK during the winter period from 2007 to 2013. Although the resulting parametric multivariate‐normal probabilistic forecasts are marginally less sharp than those of the leading competitor, they capture the spatial structure of the observations better than a correlation structure based on either the ensembles or climatology alone, and are robust to changes in the variables and spatial domain of the forecast, at a greatly reduced computational cost. [ABSTRACT FROM AUTHOR]

Travelling wave ion mobility usually uses a calibration procedure to determine collision cross sections. Here, we investigate phosphoric acid cluster anions as possible calibrants to increase the pool of reference ions for singly and multiply charged anions with nitrogen as drift gas. Phosphoric acid solutions (5–50 mM) in water and acetonitrile were analyzed using electrospray ionization in the negative ion mode. Collision cross sections were obtained using an IMS-TOF drift tube ion mobility mass spectrometer (Tofwerk, Thun, Switzerland) (DTIMS-MS) on which we varied the electric field. Twenty-six collision cross sections from DTIMS-MS in nitrogen gas, termed DTCCS(N 2), were obtained for singly, doubly and triply charged phosphoric acid cluster anions which range from 146 to 530 Å2. Reduced mobilities K 0 ranged from 0.767 to 1.435 cm2 V−1 s−1 for singly charged cluster anions, 1.177 to 1.006 cm2 V−1 s−1 and 1.250 to 1.0143 cm2 V−1 s−1 for doubly and triply charged cluster anions, respectively. The DTCCS(N 2) were found fitted to a power function 80 n 0.51 where n is the aggregation number. Ion mobility mass spectrometry measurements were also carried out on a travelling wave ion mobility mass spectrometry (TWIMS-MS) device (SYNAPT G2 HDMS, Waters Corp., Manchester, UK). The DTCCS(N 2) were well correlated to the drift times measured on the TWIM instrument (R2 above 0.9999). The correlation function was found to depend on the charge state of the ions. Accuracy tests evidenced a systematic error of 9–11 Å2 (4–6%) on singly charged ions of polyalanine, dextran and hexakis(fluoroalkoxy)phosphazine compared to literature values. Although absolute values were shifted, CCS differences were preserved. Image 1 • Twenty-six collision cross sections (CCS) values in nitrogen of phosphoric acid cluster anions. • CCS determined with drift tube ion mobility mass spectrometry from the first-principles. • Excellent correlation between these CCS and drift times measured on the travelling wave ion mobility instrument. [ABSTRACT FROM AUTHOR]

A simple and robust method for calibrating ceilometers has been tested in an operational environment, demonstrating that the calibrations are stable to better than ±5 % over a period of a year. The method relies on using the integrated backscatter (B) from liquid clouds that totally extinguish the ceilometer signal; B is inversely proportional to the lidar ratio (S) of the backscatter to the extinction for cloud droplets. The calibration technique involves scaling the observed backscatter so that B matches the predicted value for S of 18.8±0.8 sr for cloud droplets, at ceilometer wavelengths. For accurate calibration, care must be taken to only use profiles where the range correction is implemented and to exclude any profiles having targets with different values of S , such as drizzle drops and aerosol particles, profiles that do not totally extinguish the ceilometer signal, profiles with low cloud bases that saturate the receiver, and any profiles for which the window transmission or the lidar pulse energy falls below 90 %. A range-dependent multiple-scattering correction that depends on the ceilometer optics should also be applied to the profile. For ceilometers operating at around 910 nm wavelength, a simple correction for water vapour attenuation is applied to the signal using the vapour profiles from a forecast analysis. For a generic ceilometer in the UK the 90 d running mean of the calibration coefficient over a period of 20 months is constant to within 3 % with no detectable annual cycle, thus confirming the validity of the humidity and multiple-scattering correction. For Gibraltar, where cloud cover is less prevalent than in the UK, the 90 d running mean calibration coefficient was constant to within 4 %. The more sensitive ceilometer model operating at 1064 nm is unaffected by water vapour attenuation but is more prone to saturation in liquid clouds; such profiles can be recognised and rejected and, despite the more restricted sample of cloud profiles, a robust calibration is readily achieved. In the UK, the running mean 90 d calibration coefficients varied by about 4 % over a period of 1 year. The consistency of profiles observed by nine pairs of co-located ceilometers in the UK Met Office network operating at around 910 and 1064 nm provided independent validation of the calibration technique. In all cases, if quantitative and reliable backscatter observations are to be obtained it is essential to keep the window clean. This may be a challenge in dusty locations. EUMETNET is currently networking 700 European ceilometers so they can provide ceilometer profiles in near real time to European weather forecast centres and has adopted the cloud calibration technique described in this paper for ceilometers with a wavelength of around 910 nm. [ABSTRACT FROM AUTHOR]

Information about the presence and movement of water is crucial to understanding stone deterioration and rock weathering but hard to obtain. Non-destructive, non-invasive measurements of electromagnetic phenomena can provide proxy data on water contents within porous stone and rock. Commercial geophysical devices, such as radar and microwave moisture sensors, produce raw data or readings in arbitrary units, but can be related to absolute water contents through gravimetric calibration. Calibration procedures typically either equilibrate samples to a set of relative humidities (RH%) using salt solutions or environmental chambers (requiring specialised equipment), or monitor ambient drying which yields less homogenous moisture distributions and takes time. This study proposes and tests a cost- and time-effective 'isolated diffusion' gravimetric calibration procedure in which a set of samples are sealed at specific water contents and equilibrated. The procedure is compared to ambient drying over 120 h for three United Kingdom building stones and evaluated with modelled reflection coefficients and relative permittivities. The calibrations determined from isolated diffusion more closely follow modelled behaviour than those from ambient drying, as the calibrations developed from the latter were affected by uneven distributions of moisture. Calibrations for radar measurements developed from two types of back interfaces (air and metal) were very similar to one another, suggesting that measurements are consistent regardless of the type of back interface used. The isolated diffusion calibration procedure provides a cost-effective and simple method to facilitate comparison between different non-destructive testing methods and enables accurate measurement of water contents in porous geomaterials. • A procedure is proposed for 'isolated diffusion' gravimetric calibration. • Calibrations were developed for radar and microwave sensors for UK building stones. • Dielectric constants and reflection coefficients were modelled. • 'Isolated diffusion' calibrations more closely matched models than ambient drying. • The procedure produces low-cost, accurate calibrations without specialised equipment. [ABSTRACT FROM AUTHOR]

Aim: To evaluate the cost‐effectiveness of needle and syringe programmes (NSPs) compared with no NSPs on hepatitis C virus (HCV) transmission in the United Kingdom. Design Cost‐effectiveness analysis from a National Health Service (NHS)/health‐provider perspective, utilizing a dynamic transmission model of HCV infection and disease progression, calibrated using city‐specific surveillance and survey data, and primary data collection on NSP costs. The effectiveness of NSPs preventing HCV acquisition was based on empirical evidence. Setting and participants: UK settings with different chronic HCV prevalence among people who inject drugs (PWID): Dundee (26%), Walsall (18%) and Bristol (45%) Interventions: Current NSP provision is compared with a counterfactual scenario where NSPs are removed for 10 years and then returned to existing levels with effects collected for 40 years. Measurements HCV infections and cost per quality‐adjusted life year (QALY) gained through NSPs over 50 years. Findings Compared with a willingness‐to‐pay threshold of £20 000 per QALY gained, NSPs were highly cost‐effective over a time‐horizon of 50 years and decreased the number of HCV incident infections. The mean incremental cost‐effectiveness ratio was cost‐saving in Dundee and Bristol, and £596 per QALY gained in Walsall, with 78, 46 and 40% of simulations being cost‐saving in each city, respectively, with differences driven by coverage of NSP and HCV prevalence (lowest in Walsall). More than 90% of simulations were cost‐effective at the willingness‐to‐pay threshold. Results were robust to sensitivity analyses, including varying the time‐horizon, HCV treatment cost and numbers of HCV treatments per year. Conclusions: Needle and syringe programmes are a highly effective low‐cost intervention to reduce hepatitis C virus transmission, and in some settings they are cost‐saving. Needle and syringe programmes are likely to remain cost‐effective irrespective of changes in hepatitis C virus treatment cost and scale‐up. [ABSTRACT FROM AUTHOR]

Highlights • The paper presents a verification of HDM-4 fuel consumption estimates by comparing these to real world measurements from a large dataset from a truck telematic database. • Results of the study show that the latest calibration of HDM-4 performed in UK is not able to estimate the fuel consumption of the considered fleet of trucks reliably. • The authors suggest that, in order to use HDM-4 at a strategic level in road asset management, a full recalibration of the model should be performed in UK. • Results show also that analysis of the 'big data' available in the telematic database of fleet managers can help in updating HDM-4 without performing new experiments and can represent a valid alternative to the traditional approach. Abstract This paper presents an assessment of the accuracy of the HDM-4 fuel consumption model calibrated for the United Kingdom and evaluates the need for further calibration of the model. The study focuses on HGVs and compares estimates made by HDM-4 to measurements from a large fleet of vehicles driving on motorways in England. The data was obtained from the telematic database of truck fleet managers (SAE J1939) and includes three types of HGVs: light, medium and heavy trucks. Some 19,991 records from 1645 trucks are available in total. These represent records of trucks driving at constant speed along part of the M1 and the M18, two motorways in England. These conditions have been simulated in HDM-4 by computing fuel consumption for each truck type driving at a constant speed of 85 km/h on a flat and straight road segment in good condition. Estimates are compared to real measurements under two separate sets of assumptions. First, the HDM-4 model calibrated for the UK has been used. Then, the model was updated to take into account vehicle weight and frontal area specific to the considered vehicles. The paper shows that the current calibration of HDM-4 for the United Kingdom already requires recalibration. The quality of the model estimates can be improved significantly by updating vehicle weight and frontal area in HDM-4. The use of HGV fleet and network condition data as described in this paper provides an opportunity to verify HDM-4 continuously. [ABSTRACT FROM AUTHOR]

In the stores of the British Museum are three exquisite springs, made in the late 1820s and 1830s, to regulate the most precise timepieces in the world. Barely the thickness of a hair, they are exquisite because they are made entirely of glass. Combining new documentary evidence, funded by the Antiquarian Horological Society, with the first technical analysis of the springs, undertaken in collaboration with the British Museum, the research presented here uncovers their extraordinary significance to the global extension of nineteenth century capitalism through the repeal of the Corn Laws. In the 1830s and 1840s the Astronomer Royal, George Biddell Airy; the Hydrographer to the Admiralty, Francis Beaufort; and the Prime Minister, Sir Robert Peel, collaborated with the virtuoso chronometer-maker, Edward John Dent, to mobilize the specificity of particular forms of glass, the salience of the Glass Tax, and the significance of state standards, as means to reform. These protagonists looked to glass and its properties to transform the fiscal military state into an exquisitely regulated machine with the appearance of automation and the gloss of the free-trade liberal ideal. Surprising but significant connections, linking Newcastle mobs to tales of Cinderella and the use of small change, demonstrate why historians must attend to materials and how such attention exposes claims to knowledge, the interests behind such claims, and the impact they have had upon the design and architecture of the modern world. Through the pivotal role of glass, this paper reveals the entangled emergence of state and market capitalism, and how the means of production was transformed in vitreous proportions. [ABSTRACT FROM AUTHOR]

We report the calibration of the Orion High-Resolution X-ray (OHREX) imaging crystal spectrometer at the EBIT-I electron beam ion trap at Livermore. Two such instruments, dubbed OHREX-1 and OHREX-2, are fielded for plasma diagnostics at the Orion laser facility in the United Kingdom. The OHREX spectrometer can simultaneously house two spherically bent crystals with a radius of curvature of r = 67.2 cm. The focusing properties of the spectrometer allow both for larger distance to the source due to the increase in collected light and for observation of extended sources. OHREX is designed to cover a 2.5°-3° spectral range at Bragg angles around 51.3°. The typically high resolving powers at these large Bragg angles are ideally suited for line shape diagnostics. For instance, the nominal resolving power of the instrument (>10 000) is much higher than the effective resolving power associated with the Doppler broadening due to the temperature of the trapped ions in EBIT-I. The effective resolving power is only around 3000 at typical EBIT-I conditions, which nevertheless is sufficient to set up and test the instrument's spectral characteristics.We have calibrated the spectral range for a number of crystals using well known reference lines in the first and second order and derived the ion temperatures from these lines. We have also made use of the 50 μm size of the EBIT-I source width to characterize the spatial focusing of the spectrometer. [ABSTRACT FROM AUTHOR]

The care of the elderly with hip fractures and their outcomes might be improved with resources targeted by the accurate calculation of risks of mortality and morbidity. We used a multicentre national dataset to evaluate and recalibrate the Nottingham Hip Fracture Score and Surgical Outcome Risk Tool. We split 9,017 hip fracture cases from the Anaesthesia Sprint Audit of Practice into derivation and validation data sets and used logistic regression to derive new model co-efficients for death at 30 postoperative days. The area (95% CI) under the receiver operator characteristic curve of 0.71 (0.67-0.75) indicated acceptable discrimination by the Nottingham Hip Fracture Score and acceptable calibration fit (Hosmer-Lemeshow test), p = 0.23, with a similar discrimination by the Surgical Outcome Risk Tool, 0.70 (0.66-0.74), which was miscalibrated to the observed data, p = 0.001. We recommend that studies test these scores for patients with hip fractures in other countries. We also recommend these models are compared with case-mix adjustment tools used in the UK. [ABSTRACT FROM AUTHOR]

The article discusses the importance of calibration for nurse practice equipment. Topics include the importance of medical devices in health care, a discussion of what calibration is and the role of the Care Quality Commission (CQC) in the safety of general practice (GP), and an overview of different medical devices such as sphygmomanometers and thermometers. Also mentioned are pulse oximeter, dopplers, and spirometer.

The urban morphology is characterised by self-organisation where interactions of multiple agents produce emerging patterns on the urban form. Port-urban relationship added to the complexity of port cities' urban form. Most urban cellular automata (CA) models simulate land-use evolution through transition rules representing multi-factored local interactions. However, calibration of CA-based urban land use and transport interaction (LUTI) models often utilise manual methods due to complexity of the process. This limits insights on urban interactions to a few explored settlements and prevents applications for planning and assessment of transport policies in other contexts. This paper, therefore, addresses three main points. The paper (i) demonstrates an improved method for the calibration of CA-based LUTI models, (ii) contributes to a better understanding of the urban dynamics in port city systems by quantifying generalizable interactions from a wide range of port-urban settlements, and (iii) illustrates how the use of these interactions in a simulation model can allow long-term impact predictions of planning interventions. These were done by formulating a model in a similar structure as a neural network model to enable automatic calibration using an application of the gradient-descent algorithm. The model was then used to quantify the dynamics between land-use, geographic, and transport factors in 46 port-based and 10 non-port settlements across Great Britain, thus enabling cross-sectional analysis. Cluster analysis of the calibrated interactions in the study areas was conducted to examine the variations of these interactions. This produced two main groups. In the first group, consisting larger settlements, connections between ports and other urban activities were weaker than in the second group which consisted of smaller port-settlements. Overall, the findings of the research are consistent with existing evidence in the port-cities literature but go further in quantifying the interaction between urban agents within port-urban systems of various sizes and types. These quantified interactions will enable planners to better predict the longer-term consequences of their interventions. • This paper improved calibration process of urban model using optimization method from machine learning • The improved process allowed examination of wide range of port cities to counter the current trend of case-specific studies • Quantified interactions from wide range of port cities provide insights of the different land use behaviour in different types of port cities • Port-urban interactions in smaller urban areas with port are stronger thn in most other port cities • Interactions quantified in the study can be used in simulation to predict future port city urban form [ABSTRACT FROM AUTHOR]

During the evolution of the COVID-19 pandemic, each country has adopted different control measures to contrast the epidemic's diffusion. Restrictions to mobility, public transport, and social life in general have been actuated to contain the spread of the pandemic. In this paper, we consider the deterministic SIRD model with delays proposed by Calleri et al., which is improved by adding the vaccinated compartment V (SIRDV model) and considering a time-dependent contact frequency. The three delays take into account the incubation time of the disease, the healing time, and the death time. The aim of this work is to study the effect of the vaccination campaigns in Great Britain (GBR) and Israel (ISR) during the pandemic period. The different restriction periods are included by fitting the contact frequency on real datasets as a piecewise constant function. As expected, the vaccination campaign reduces the amount of deaths and infected people. Furthermore, for the different levels of restriction policy, we find specific values of the contact frequency that can be used to predict the trend of the pandemic. [ABSTRACT FROM AUTHOR]

The rowing stroke is a leg-driven action, in which forces developed by the lower limbs provide a large proportion of power delivered to the oars. In terms of both performance and injury, it is important to initiate each stroke with powerful and symmetrical loading of the foot stretchers. The aims of this study were to assess the reliability of foot force measured by footplates developed for the Concept2 indoor ergometer and to examine the magnitude and symmetry of bilateral foot forces in different groups of rowers. Five heavyweight female scullers, six heavyweight female sweep rowers, and six lightweight male (LWM) rowers performed an incremental step test on the Concept2 ergometer. Vertical, horizontal, and resultant forces were recorded bilaterally, and asymmetries were quantified using the absolute symmetry index. Foot force was measured with high consistency (coefficient of multiple determination>0.976 ± 0.010). Relative resultant, vertical, and horizontal forces were largest in LWM rowers, whilst average foot forces significantly increased across stroke rates for all three groups of rowers. Asymmetries ranged from 5.3% for average resultant force to 28.9% for timing of peak vertical force. Asymmetries were not sensitive to stroke rate or rowing group, however, large inter-subject variability in asymmetries was evident. [ABSTRACT FROM PUBLISHER]

ABSTRACT Atmospheric observations from aircraft have played an important role in meteorological research for many years; this paper presents an overview of meteorological research done with research aircraft in the United Kingdom. Key developments from throughout the history of meteorological research flying in the United Kingdom are presented, along with highlights of UK atmospheric research flying done in the last decade using the Facility for Airborne Atmospheric Measurements ( FAAM) BAe-146 aircraft. The work presented includes research into thermodynamics, cloud processes, atmospheric aerosol, radiative transfer and atmospheric chemistry. Research aircraft provide a unique platform for the observation of atmospheric processes, allowing targeted measurement of specific parameters at a range of altitudes throughout the atmosphere. These measurements have improved greatly the understanding of the Earth's atmosphere, and the impact of these measurements has been seen through improvements in the representation of physical processes within numerical weather prediction ( NWP) and climate models. Research aircraft have also been used extensively for the calibration and validation of remote sensing measurements, providing a unique test-bed for satellite observations. This research has led to improved use of satellite observations that have enhanced greatly how the atmosphere is viewed. Many developments in atmospheric research would not have been possible without the use of aircraft measurements, and these measurements will continue to play a key role in future developments of meteorological observation and prediction, as the complexity and resolution of weather and climate models increases. [ABSTRACT FROM AUTHOR]

Wan Jaafar, Wan Zurina, and Dawei Han, 2012. Calibration Catchment Selection for Flood Regionalization Modeling. Journal of the American Water Resources Association (JAWRA) 48(4): 698-706. DOI: 10.1111/j.1752-1688.2012.00648.x Abstract: There are two unsolved problems in flood regionalization model development related to the quantity and quality of calibration catchments: (1) how many calibration catchments should be used? and (2) how to select the calibration catchments? This study explores these two questions through a case study on the median annual maximum flood (QMED) model in the United Kingdom. It has been found that the chance of developing a good QMED model decreases significantly when the number of calibration catchments drops below a critical number (e.g., 60 in the case study). However, no significant improvement is achieved if the number of calibration catchments is above it. This number could be used as a benchmark for choosing randomly selected calibration catchments. Across a broad range of calibration catchment numbers, there are good and poor calibrated models regardless of calibration catchment numbers. High quality models could be developed from a small number of calibration catchments and also poor models from a large number of calibration catchments. This indicates that the number of calibration catchments may not be the dominating factor for developing a high quality regionalization model. Instead, the information content could be more important. The study has demonstrated that the standard deviation values between the best and poorest groups are distinctive and could be used in choosing appropriate calibration catchments. [ABSTRACT FROM AUTHOR]

We investigate how well the variability of extreme daily precipitation events across the United Kingdom is represented in a set of regional climate models and the E-OBS gridded data set. Instead of simply evaluating the climatologies of extreme precipitation measures, we develop an approach to validate the representation of physical mechanisms controlling extreme precipitation variability. In part I of this study we applied a statistical model to investigate the influence of the synoptic scale atmospheric circulation on extreme precipitation using observational rain gauge data. More specifically, airflow strength, direction and vorticity are used as predictors for the parameters of the generalised extreme value (GEV) distribution of local precipitation extremes. Here we employ this statistical model for our validation study. In a first step, the statistical model is calibrated against a gridded precipitation data set provided by the UK Met Office. In a second step, the same statistical model is calibrated against 14 ERA40 driven 25 km resolution RCMs from the ENSEMBLES project and the E-OBS gridded data set. Validation indices describing relevant physical mechanisms are derived from the statistical models for observations and RCMs and are compared using pattern standard deviation, pattern correlation and centered pattern root mean squared error as validation measures. The results for the different RCMs and E-OBS are visualised using Taylor diagrams. We show that the RCMs adequately simulate moderately extreme precipitation and the influence of airflow strength and vorticity on precipitation extremes, but show deficits in representing the influence of airflow direction. Also very rare extremes are misrepresented, but this result is afflicted with a high uncertainty. E-OBS shows considerable biases, in particular in regions of sparse data. The proposed approach might be used to validate other physical relationships in regional as well as global climate models. [ABSTRACT FROM AUTHOR]

Objectives: To evaluate the discrimination, calibration, and net benefit performance of the Prostate Cancer Prevention Trial Risk Calculator (PCPTRC) across five European randomized study of screening for prostate cancer (ERSPC), 1 United Kingdom, 1 Austrian, and 3 US biopsy cohorts. Methods: PCPTRC risks were calculated for 25,733 biopsies using prostate-specific antigen (PSA), digital rectal examination, family history, history of prior biopsy, and imputation for missing covariates. Predictions were evaluated using the areas underneath the receiver operating characteristic curves (AUC), discrimination slopes, chi-square tests of goodness of fit, and net benefit decision curves. Results: AUCs of the PCPTRC ranged from a low of 56% in the ERSPC Goeteborg Rounds 2-6 cohort to a high of 72% in the ERSPC Goeteborg Round 1 cohort and were statistically significantly higher than that of PSA in 6 out of the 10 cohorts. The PCPTRC was well calibrated in the SABOR, Tyrol, and Durham cohorts. There was limited to no net benefit to using the PCPTRC for biopsy referral compared to biopsying all or no men in all five ERSPC cohorts and benefit within a limited range of risk thresholds in all other cohorts. Conclusions: External validation of the PCPTRC across ten cohorts revealed varying degree of success highly dependent on the cohort, most likely due to different criteria for and work-up before biopsy. Future validation studies of new calculators for prostate cancer should acknowledge the potential impact of the specific cohort studied when reporting successful versus failed validation. [ABSTRACT FROM AUTHOR]

The article presents a study which aims to provide the first inter-laboratory calibration results in Great Britain for very short-lived halocarbons (VSLH). The study compared the calibration techniques of laboratories in several universities including University of Cambridge (UoC), University of East Anglia (UEA), and University of York (UoY). Results show that cross-calibration between gaseous and dissolved VSLH is not straightforward as larger discrepancies are observed between gas phase.

Abstract: The Severn Estuary has a spring tidal range approaching 14m, which is among the highest tides in the world. Various proposals have been made regarding the construction of a tidal barrage across the estuary to enable tidal energy to be generated. The aim of the current study is to investigate the impact of constructing a tidal barrage on the hydrodynamic processes in the Severn Estuary using a numerical model. A two-dimensional hydrodynamic model based on an unstructured triangular mesh has been used in this study. The model employs a TVD finite volume method to solve the 2D shallow water equations, with the numerical scheme being second-order accurate in both time and space. The model has been calibrated by comparing model predictions with observed tidal levels and currents at different sites, for typical spring and neap tides, and it has also been verified using tidal level time series at four tide gauging stations measured in 2003. In order to predict the hydrodynamic processes with a barrage, the model domain was divided into two subdomains: one each side of the barrage. Details were given of the method used for representing the various hydraulic structures, including the sluices and turbines, along the proposed Cardiff-Weston barrage. The impact of constructing the barrage on the water levels and velocities was then investigated using this model. Model-predicted hydrodynamic parameters, without and with the barrage, were analysed in detail. Model predictions indicated that with the barrage the mean power output could reach 2.0GW with up to 25GWh units of electricity being generated over a typical mean spring tidal cycle. At some cross-sections, the maximum discharges were predicted to decrease by 30–50%, as compared with the corresponding discharges predicted without the barrage. The model also predicted that with the barrage, the maximum water levels upstream of the barrage would decrease by 0.5–1.5m, and with the peak tidal currents also being reduced considerably. For different operating modes, complex velocity fields were predicted to occur in the vicinity of the barrage. [Copyright &y& Elsevier]

Abstract: A suite of 11 sections through the Oxfordian (Upper Jurassic) strata in the Dorset and Yorkshire regions of England and the Isle of Skye in Scotland yielded magnetic polarity patterns directly calibrated to the ammonite biostratigraphy of the Boreal and the Subboreal faunal provinces. The sections include the leading candidate for the global stratotype (GSSP) for the Callovian–Oxfordian stage boundary. The mean Oxfordian paleomagnetic pole derived from the Dorset and Yorkshire sections is 71.3°N, 172.6°E (δp =4.2°, δm =6.1°). The integrated magneto-biostratigraphic scale is consistent with results from the Sub-Mediterranean faunal province and extends the polarity pattern to the base of the Oxfordian. After adjusting for the estimated durations of ammonite subzones from cycle stratigraphy, the magnetostratigraphy confirms models for marine magnetic anomalies M30 through to M37, including some of the short-duration features recorded by deep-tow magnetic surveys in the western Pacific. The Callovian–Oxfordian boundary (base of Quenstedtoceras mariae Zone) occurs in a normal-polarity zone that is correlated to the youngest part of polarity chron M37n of this extension to the M-sequence. [Copyright &y& Elsevier]

Abstract: In this study, geographically weighted summary statistics (GWSSs) are used to investigate spatial variation and spatial relationships in a freshwater acidification critical load data set covering Great Britain. This use of GWSSs not only provides valuable insight into the critical load process prior to a geographically weighted regression (GWR) calibration, but also helps in interpreting its output. GWSSs are similarly useful prior to the calibration of other spatial models, such as those used in geostatistics. Results agree with those of previous research, where relationships between critical load and contextual catchment data can vary across space. However the more sophisticated models used here are shown to be much more flexible and informative, allowing more spatial patterns to be revealed than before. [Copyright &y& Elsevier]

Abstract: The present research has two main objectives (1) to build two models for concentration prediction in a stream subject to a pollutant release and (2) to investigate options for estimating the parameters of the models. The models rely on the fundamental advection–dispersion equation and were developed, calibrated and evaluated using tracer data from experiments conducted in the Murray Burn in Edinburgh, UK. During the evaluation by comparison against field data both models were able to predict the main features of the observations at the first three monitoring sites, but results at the final site were less good. These types of models rely very much on the ability to make good estimates of velocity and dispersion coefficients along the stream. Although these parameters could be estimated using tracer experiments, it would be easier if they could be estimated from other hydraulic data such as the water flow rate and the channel characteristics. For the Murray Burn such models for parameter estimation were developed in the form of non-linear relationships with flow rate. This approach could be used to calculate the parameters for other similar streams, if the coefficients in the equations were similar. Alternatively, further work would be needed to explore how these coefficients vary between streams. [Copyright &y& Elsevier]

A melting point measurement facility for the UK has been developed and accredited to ISO/IEC 17025 Calibration status for the determination of the liquefaction temperature of pure substances from 35 to 250°C. The facility is based upon a commercial instrument, i.e. an oil bath fitted with an aluminium block (Isotech, model 798 EHT), a precision multimeter (Isotech TTI-7), a thermocouple directly inserted in the sample under investigation and a platinum resistance thermometer (PRT) tracking the block temperature. The homogeneity of temperature bath/block was investigated and the PRT used for the traceability of the measurements was calibrated by NPL and traceable to ITS-90. The process was validated using four current LGC Certified Reference Materials (CRMs): [ABSTRACT FROM AUTHOR]

Summary: This paper presents a methodology to calibrate hydraulic models using possibility of inundation maps derived from satellite imagery. The study was performed on a river reach of the Lower Dee, UK, where a coarse resolution image (ENVISAT ASAR) and high resolution satellite image (ERS-2 SAR) were acquired at the same time during the December 2006 flood event. Ten different flood extent maps were derived from the two flood images by using five different procedures to process these data. These flood extent maps were used to perform a sensitivity analysis of a simple raster-based inundation model (LISFLOOD-FP). The sensitivity analysis enabled us to investigate the capability of the two different resolution images to calibrate the friction parameters of the flood inundation model. The analysis showed that the optimal parameters of the model depend on the type of satellite image used to evaluate the model as well as on the particular procedure used to derive the flood extent map. Finally, the study developed a novel methodology to calibrate flood inundation models by comparing the model results to a possibility of inundation map obtained by combining the ten different flood extent maps. [Copyright &y& Elsevier]

In this paper, we describe the photometric calibration of data taken with the near-infrared Wide Field Camera (WFCAM) on the United Kingdom Infrared Telescope (UKIRT). The broad-band ZYJHK data are directly calibrated from Two-Micron All-Sky Survey (2MASS) point sources which are abundant in every WFCAM pointing. We perform an analysis of spatial systematics in the photometric calibration, both inter- and intradetector show that these are present at up to the ∼5 per cent level in WFCAM. Although the causes of these systematics are not yet fully understood, a method for their removal is developed and tested. Following the application of the correction procedure, the photometric calibration of WFCAM is found to be accurate to ≃1.5 per cent for the JHK bands and 2 per cent for the ZY bands, meeting the survey requirements. We investigate the transformations between the 2MASS and WFCAM systems and find that the Z and Y calibrations are sensitive to the effects of interstellar reddening for large values of , but that the JHK filters remain largely unaffected. We measure a small correction to the WFCAM Y-band photometry required to place WFCAM on a Vega system, and investigate WFCAM measurements of published standard stars from the list of UKIRT faint standards. Finally, we present empirically determined throughput measurements for WFCAM. [ABSTRACT FROM AUTHOR]

Flickermeter calibrations currently rely on the predicted response of a standard flickermeter to basic waveforms. A description is given of an interpretation and implementation of the IEC standard flickermeter, developed at the National Physical Laboratory (NPL), to assess the response of commercial flickermeters to more complex waveforms, which are representative of signals that occur in practice. A description of the incorporation of the resulting model into a calibration system for flickermeters under complex-waveform conditions is given. [ABSTRACT FROM AUTHOR]

A letter to the editor is presented regarding a study on the use of an auditory-evoked response simulator which is aimed at providing a traceability for newborn hearing screening devices.

The probability of extreme sea levels along the coasts has always been statistically estimated from the series of local observations. The inference is never conclusive, and an attempt is given here to improve the methods already used with reference to the area of the English Channel. The joint probability method (JPM) is the starting point: In most cases it underestimates the return times (or overestimates extreme levels at a fixed time). The proposed extension is based on a more careful use of observed extremes by fitting a coefficient Cc deduced from the data set, which requires that the maximum record height be in agreement with the return period of the record length. This correction calibrates the whole series of extreme estimations to the observed maximum. Likewise an attempt to roughly explain this correction is given that explores the tide-surge interaction and seasonal dependence. The parameters are specifically computed for 15 tide-gauge stations, and the comparison is extended to other known methods, like the Gumbel one (in most cases overestimating the levels) and GEV simulations (which appear much better). Finally extreme levels with estimated return times of 10, 50, and 100 years, respectively, are proposed for each site, and a test for validity was performed by splitting certain long records into small samples, thus checking the spread of the results. [ABSTRACT FROM AUTHOR]

SPIDER (simulating pesticides in ditches to assess ecological risk) is a locally distributed, capacitance-based model that accounts for pesticide entry into surface water bodies via spray drift, surface runoff, interlayer flow and drainage. SPIDER was developed for application to small agricultural catchments. Transport of pesticide from site of application to surface water via subsurface field drains is one of the major routes of entry to surface water. Several pesticide fate models describe transfer of pesticide via drainflow, notably MACRO which has been evaluated against field data in several studies. The capacity of SPIDER to simulate drainflow and pesticide concentration in drain water was evaluated against two datasets that had been used previously to evaluate MACRO independently of this study: a plot experiment at Cockle Park and a field experiment at Maidwell, both located in the UK. In both circumstances, SPIDER was able to reproduce drain hydrographs relatively well with no or limited calibration. At Cockle Park, simulated and observed drainflow over the season were 240 and 278 mm, respectively with a Nash and Sutcliffe model efficiency (NSME) coefficient of 0.32 whilst at Maidwell they were 259 and 296 mm, respectively with a NSME coefficient of 0.55. Prediction of maximum isoproturon concentration at Cockle Park by SPIDER and MACRO were 5.3 and 13.1 μg L− 1 respectively compared to the 3.8 μg L− 1 measured in the field, whilst pesticide load to drains over the season were 0.22 and 1.53 g, respectively, compared to an observed load of 0.35 g. Maximum sulfosulfuron concentration at Maidwell were 2.3, 3.9 and 5.4 μg L− 1 for observed and as simulated by SPIDER and MACRO, respectively and pesticide loading to drains of the season was 0.77, 5.61, 4.77 g, respectively. Results from the sensitivity analysis showed that the sensitivity of SPIDER compared favourably to that of several other capacity models but was more sensitive than MACRO to variations in input parameters. SPIDER is currently being tested at the catchment scale. [Copyright &y& Elsevier]

The growing need for standardized units of measure led to major metrological reforms in the mid-nineteenth century. This paper focusses on their implementation in the Kingdom of Hanover and the involvement of C.F. Gauss. His papers reveal how much the success of his precision measurements hinged on the skill of his mechanic M. Meyerstein. A discussion of the regional weights and measures and the standardization procedure is followed by a description of various precision balances and the weighing methods employed as well as a review of the problems posed by reliable length calibration. The success of the enterprise rested not only on intellectual prestige and ministerial clout but also on the hands-on skill of the mechanical practitioner. [ABSTRACT FROM AUTHOR]

Objective: This study investigated the use of clinical dental auxiliaries as examiners in caries prevalence surveys of 5- and 12-year-old children in the United Kingdom. Methods: A random sample of four therapists and four hygienists was drawn from 23 clinical dental auxiliaries employed in Community Dental service in Yorkshire, United Kingdom. Training and calibration were carried out according to national guidelines for caries prevalence surveys. Sixteen 5- year-old and sixteen 12-year-old children were examined in the calibration exercise. Agreement was assessed using 95% confidence intervals of mean dmft/DMFT of the group, sensitivity and specificity values, an kappa statistics on dft/DFT. Results: For 5-year-old children, a good level of agreement with the standard examiner was achieved with sensitivity scores ranging from 0.84-0.98, specificity scores from 0.93-0.97, and kappa scores from 0.80-0.89. For 12-year-old children, sensitivity scores ranged from 0.56-0.95; specificity scores from 0.93-0.99; and kappa scores from 0.66-0.83. Four examiners failed to achieve the minimum scores on all measurements. Conclusion: It was concluded that clinical dental auxiliaries could be used as examiners in caries prevalence surveys of 5-year-old children. However, in order to attempt to meet the national standard for agreement in surveys of 12-year-old children, four of the eight examiners in the present study would require further training. Possible reasons for this difference are discussed. [ABSTRACT FROM AUTHOR]

The common whelk, Buccinum undatum , is a commercially important gastropod found throughout the North Atlantic. One method of age and life history analysis for gastropod species is the use of oxygen isotope ratio (δ18O) measurements from their shells, which is a well-established technique for the reconstruction of historical seawater temperatures at the time of shell biomineralization. Palaeotemperature calibrations have been developed for different types of calcium carbonate as well as species-specific equations to produce the most accurate seawater temperature reconstructions. Here we investigate the four-layer internal structure of B. undatum shells and confirm an aragonite composition using Micro-Raman Spectroscopy (MRS). We then calibrate a species-specific palaeotemperature equation for this gastropod species. This was achieved through the isotopic analysis of shells from laboratory reared specimens of known provenance reared at specific seawater temperatures to produce the following: t(°C) = 14.96 (± 0.15) – 4.94 (± 0.22) x (δ18O shell – δ18O water) The calibrated equation differs significantly from previously published data derived from both aragonite and calcite. An offset of 1.04‰ (± 0.41‰) was discovered between observed δ18O Shell values and those expected under equilibrium, suggesting a species-specific vital effect. The calibrated equation was used to reconstruct accurate, high resolution historical seawater temperatures from three sites across the U.K. (Shetland, the Menai Strait and Jersey). With this new accurate calibration, both modern and fossil B. undatum shells now have the potential to be employed as high-resolution archives of recent and historical seawater temperature. • New equation accurately reconstructs seawater temperatures from 3 sites around UK. • B. undatum shells produced equation with a clear offset from previous studies. • Fast growth makes B. undatum ideal for high-resolution reconstructions. [ABSTRACT FROM AUTHOR]

In the past 12 years, the United Kingdom (UK) has made significant progress in making domestic dwellings more efficient. Presently, the domestic sector is required to meet the UK's net-zero target in new and renovated dwellings by 2050. As a measure in this on-going determination, the UK has constructed a number of Zero Energy Bill Homes (ZEBH) in Corby, Northamptonshire, which is currently a part of the European Union District of Future Project. For the effectiveness of a zero energy bill performance, a solar photovoltaic thermal-assisted heat pump (SPVTAH) was modelled, which represented building modelling, emphasising the essential outcomes through energy demand profiles (electricity, space heat, and domestic hot water), and occupant behaviour. To authenticate the building modelling, the baseline models were calibrated using the weekly electricity-use curve and validated using statistical indices. It is inferred that the evidence-based manual calibration technique has fairly validated the energy-use profiles of the chosen case studies and is found to be within acceptable tolerance levels. In addition, to verify the zero-energy bill status of the buildings, an economic analysis was extremely crucial. A feasibility assessment indicated that the ZEBH concept will be impractical if the UK government subsidies are withdrawn. Moreover, the Net Present Value analysis further signified that although SPVTAH seemingly generates revenues, the initial investment turned out to be the largest barrier to repay for the system. However, it was proven that the renewable energy technology operational in the domestic dwellings of the UK does offer major advantages, and reduction in costs appears to be the most significant one. [ABSTRACT FROM AUTHOR]