Tests of a Semi-Analytical Case 1 and Gelbstoff Case 2 SeaWiFS Algorithm with a Global Data Set

A semi-analytical algorithm was tested with a total of 733 points of either unpackaged or packaged-pigment data, with corresponding algorithm parameters for each data type. The 'unpackaged' type consisted of data sets that were generally consistent with the Case 1 CZCS algorithm and other well calibrated data sets. The 'packaged' type consisted of data sets apparently containing somewhat more packaged pigments, requiring modification of the absorption parameters of the model consistent with the CalCOFI study area. This resulted in two equally divided data sets. A more thorough scrutiny of these and other data sets using a semianalytical model requires improved knowledge of the phytoplankton and gelbstoff of the specific environment studied. Since the semi-analytical algorithm is dependent upon 4 spectral channels including the 412 nm channel, while most other algorithms are not, a means of testing data sets for consistency was sought. A numerical filter was developed to classify data sets into the above classes. The filter uses reflectance ratios, which can be determined from space. The sensitivity of such numerical filters to measurement resulting from atmospheric correction and sensor noise errors requires further study. The semi-analytical algorithm performed superbly on each of the data sets after classification, resulting in RMS1 errors of 0.107 and 0.121, respectively, for the unpackaged and packaged data-set classes, with little bias and slopes near 1.0. In combination, the RMS1 performance was 0.114. While these numbers appear rather sterling, one must bear in mind what mis-classification does to the results. Using an average or compromise parameterization on the modified global data set yielded an RMS1 error of 0.171, while using the unpackaged parameterization on the global evaluation data set yielded an RMS1 error of 0.284. So, without classification, the algorithm performs better globally using the average parameters than it does using the unpackaged parameters. Finally, the effects of even more extreme pigment packaging must be examined in order to improve algorithm performance at high latitudes. Note, however, that the North Sea and Mississippi River plume studies contributed data to the packaged and unpackaged classess, respectively, with little effect on algorithm performance. This suggests that gelbstoff-rich Case 2 waters do not seriously degrade performance of the semi-analytical algorithm

Using density surface models to estimate spatio-temporal changes in population densities and trend

Funding – Centre for Research into Ecological and Environmental Modelling, University of St Andrews and U.S. Geological Survey provided funding for this analysis through a studentship to RJC.Precise measures of population abundance and trend are needed for species conservation; these are most difficult to obtain for rare and rapidly changing populations. We compare uncertainty in densities estimated from spatio–temporal models with that from standard design‐based methods. Spatio–temporal models allow us to target priority areas where, and at times when, a population may most benefit. Generalised additive models were fitted to a 31‐year time series of point‐transect surveys of an endangered Hawaiian forest bird, the Hawai'i ‘ākepa Loxops coccineus. This allowed us to estimate bird densities over space and time. We used two methods to quantify uncertainty in density estimates from the spatio–temporal model: the delta method (which assumes independence between detection and distribution parameters) and a variance propagation method. With the delta method we observed a 52% decrease in the width of the design‐based 95% confidence interval (CI), while we observed a 37% decrease in CI width when propagating the variance. We mapped bird densities as they changed across space and time, allowing managers to evaluate management actions. Integrating detection function modelling with spatio–temporal modelling exploits survey data more efficiently by producing finer‐grained abundance estimates than are possible with design‐based methods as well as producing more precise abundance estimates. Model‐based approaches require switching from making assumptions about the survey design to assumptions about bird distribution. Such a switch warrants carefully considered. In this case the model‐based approach benefits conservation planning through improved management efficiency and reduced costs by taking into account both spatial shifts and temporal changes in population abundance and distribution.Publisher PDFPeer reviewe

Phonologic Rehabilitation of Anomia in Aphasia

The single most common feature of aphasia is impairment in ability to name, whether it involves naming seen objects, or producing nouns, verbs and other words conveying meaning in spontaneous language. The traditional treatment approach to this problem is to explicitly train aphasic patients in naming. Controlled studies have shown that this approach may be quite effective. However, typically generalization is very limited, that is, the knowledge gained by the patient tends to be limited to the words actually trained, and there is at best very modest improvement in performance with untrained words (limited mainly to those that are semantically related to the trained words). Because generalization is can be limited with this approach, there currently exists no viable means of training patients on the full corpus of words (perhaps several thousand) they are likely to need in daily life. Two approaches might be taken to solving this problem: 1) develop cost effective means for providing training on several thousand words; and 2) develop alternative training methods, e.g., phonological therapy, that potentially could intrinsically generalize widely. The focus of this proposal is the second of these two approaches. Thus, the primary purpose of this Phase II clinical rehabilitation study was to examine the effect of a phonologic based treatment on confrontation naming by individuals with anomic aphasia. We used a single-subject ABA design replicated across ten participants. The primary research question asked if phonologic treatment would improve confrontation naming. Secondary research questions addressed the impact of treatment on 1) generalization to untrained behaviors such as discourse production; 2) retention effects at 3-months; 3) phonologic production and 4) nonword repetition (potential evidence of phoneme sequence knowledge acquisition)

Health promotion and disease prevention in general practice and primary care: a scoping study

This paper reports the findings of a scoping review on the organisation and delivery of health improvement activities in general practice and the primary healthcare team. The project was designed to examine who delivers these interventions, where they are located, what approaches are developed in practices and how individual practices and the primary healthcare team organise such public health activities and how these contribute to health improvement. Our focus was on health promotion and prevention activities and aimed to identify the current extent of knowledge about the health improvement activities in general practice and the wider primary healthcare team. Many of the research studies reviewed had some details about the type, process, location or who provided the intervention. Little attention is paid in the literature to examining the impact of the organisational context on the way services are delivered or how this affects the effectiveness of health improvement interventions in general practice. We found that the focus of attention is mainly on individual prevention approaches with practices engaging in both primary and secondary prevention. Although many GPs do not take a population approach and focus on individual patients some do see health promotion as an integral part of practice - whether as individual approaches to primary or secondary health improvement or as a practice-based approach to improving the health of their patients. Based on our analysis we conclude that there is insufficient good evidence to support many of the health improvement interventions undertaken in general practice and primary care

Pupil mobility, attainment and progress in secondary school

This paper is the second of two articles arising from a study of the association between pupil mobility and attainment in national tests and examinations in an inner London borough. The first article (Strand & Demie, 2006) examined the association of pupil mobility with attainment and progress during primary school. It concluded that pupil mobility had little impact on performance in national tests at age 11, once pupils’ prior attainment at age 7 and other pupil background factors such as age, sex, special educational needs, stage of fluency in English and socio-economic disadvantage were taken into account. The present article reports the results for secondary schools (age 11-16). The results indicate that pupil mobility continues to have a significant negative association with performance in public examinations at age 16, even after including statistical controls for prior attainment at age 11 and other pupil background factors. Possible reasons for the contrasting results across school phases are explored. The implications for policy and further research are discussed

Interhospital variation in the RATPAC trial (Randomised Assessment of Treatment using Panel Assay of Cardiac markers)

Background: The RATPAC trial showed that using a point-of-care panel of CK-MB(mass), myoglobin and troponin at baseline and 90 min increased the proportion of patients successfully discharged home, leading to reduced median length of initial hospital stay. However, it did not change mean hospital stay and may have increased mean costs per patient. The aim of this study was to explore variation in outcome and costs between participating hospitals. Methods: RATPAC was a pragmatic multicentre randomised controlled trial (N=2243) and economic analysis comparing diagnostic assessment using the panel to standard care for patients with acute chest pain due to suspected myocardial infarction at six hospitals. The difference in the proportion of patients successfully discharged (primary outcome) and mean costs per patient between the participating hospitals was compared. Results: Point-of-care assessment led to a higher proportion of successful discharges in four hospitals, a lower proportion in one and was equivocal in another. The OR (95% CI) for the primary outcome varied from 0.12 (0.01 to 1.03) to 11.07 (6.23 to 19.66) with significant heterogeneity between the centres (

What do we need to know to safely store CO2 beneath our shelf seas? Stakeholder workshop report

This report summarises the content and discussion of an Agile Initiative workshop held at the University of Oxford on March 1st 2024, discussing “what do we need to know to safely store CO2 in our UK continental shelf seas?