2,298 research outputs found
Karst, GIS and geological hazard planning and management in Great Britain
The British Geological Survey (BGS) database of karst features for the United Kingdom include dolines, cave entrances, stream sinks, resurgences and building damage; data for approximately half of the country has so far been gathered. BGS makes and utilises digital geological map data, which includes lithological and stratigraphical information for bedrock and superficial deposits. By incorporating this digital map data with digital elevation slope models and karst data, BGS has generated a derived dataset assessing the likelihood of subsidence due to karst collapse. This dataset is informed and verified by the karst database and marketed as part of its GeoSure suite; the karst layer includes areas of limestone, chalk, gypsum and salt. It is currently used by environmental regulators, the insurance and construction industries plus the BGS semi-automated enquiry system. The karst database and GeoSure datasets can be combined and manipulated using GIS to make other datasets that deal with specific problems. Sustainable drainage systems, some of which use soak-aways into the ground are being encouraged in the UK, but in karst areas they can cause problems. Similarly, open loop ground source heat pumps may induce subsidence if installed in certain types of karst such as chalk with overlying sand deposits. Groundwater abstraction also has the potential to trigger subsidence in karst areas. GIS manipulation of the karst information will allow the UK to be zoned into areas suitable, or unsuitable, for such uses; it has the potential to become part of a suite of planning management tools for local and National Government to assess the long term sustainable use of the ground
An enhanced classification of artificial ground
This report describes a detailed scheme for the mapping and recording of artificial ground. It presents codes and descriptions that underpin the entries in the British Geological Survey stratigraphical lexico
Increased plasma markers of oxidative stress are associated with coronary heart disease in males with diabetes mellitus and with 10-year risk in a prospective sample of males
Background: Increased oxidative stress is associated with coronary heart disease (CHD). We examined the association between plasma markers of oxidative stress and CHD in a cross-sectional sample of patients with diabetes and prospective CHD risk in a sample of men predominantly without diabetes.
Methods: Plasma total antioxidant status (TAOS) and the ratio of oxidized LDL (Ox-LDL) to LDL-cholesterol (LDL-C) were determined in a cross-section of 761 Caucasian individuals with diabetes (UDACS study). Plasma TAOS was also determined in 310 baseline samples from a 10-year prospective cohort of 3012 healthy males (NPHSII).
Results: Within UDACS, males with CHD had lower mean (SD) plasma TAOS [no CHD, 43.4 (13.2)%; CHD, 40.3 (13.8)%; P = 0.04]. The prevalence of CHD was higher in the lowest compared with the upper quartiles (32.7% vs 19.7%; P = 0.004). We observed a significant association between plasma Ox-LDL:LDL-C and CHD status [no CHD vs CHD, 16.9 (3.1) vs 19.3 (5.0) units/mmol; P = 0.04], with the prevalence of CHD being higher among men in the upper compared with lower quartiles (18.4% vs 35.1%; P = 0.003). No association was observed in females. In NPHSII, TAOS was lower in those who developed CHD [35.1 (8.0)% vs 37.1 (7.9)%; P = 0.04]. The odds ratio for CHD in the lowest compared with the upper quartile was 1.91 (95% confidence interval, 0.99–3.70; P = 0.04). This remained unchanged after adjustment for classic risk factors.
Conclusions: A cross-sectional and prospective association exists between baseline plasma measures of oxidative stress and CHD risk. The association with prospective CHD risk remained after adjustment for "traditional" risk factors, implying an independent role for oxidative stress in CHD risk
Effects of Negative Energy Components in the Constituent Quark Model
Relativistic covariance requires that in the constituent quark model for
mesons the positive energy states as well as the negative energy states are
included. Using relativistic quasi-potential equations the contribution of the
negative energy states is studied for the light and charmonium mesons. It is
found that these states change the meson mass spectrum significantly but leave
its global structure untouched.Comment: 14 pages revtex 3.0, 4 figures uudecoded attached in postscript
format, THU-93/1
Welcoming Remarks
In this transcript, first, Mr. Michael Cooper, President of the Association of the Bar of the City of New York offers welcoming remarks to the conference, describing briefly the work of the Association’s and its Special Commission on Campaign Finance Reform and the focus of the conference, specifically what can be done in the field of federal campaign finance reform based on what has been done at the state and local levels. Second, chair of the Campaign Finance Board, Father O’Hare, addressed the conference focusing on the non-partisan Board of the Campaign Finance Program in New York City as a model for overcoming the impediment to federal reform, that lawmakers view the problem in partisan terms. Father O’Hare elaborated on the purpose of the conference, briefly described new amendments to the New York City Program, an overview of the conference’s programs and speakers, and finally, a brief introduction for the first speaker, Mr. Fritz Schwarz. This transcript was taken at From the Ground Up: Local Lessons for National Reform, a national conference on campaign finance reform held on November 9, 1998, sponsored by the New York City Campaign Finance Board and the Association of the Bar of the City of New York
An exploratory evaluation of a paired maths intervention with secondary aged pupils
This study presents an exploratory evaluation of a seven week cross-age peer-tutoring mathematics intervention, Paired Maths (based on Topping, Kearney, McGee and Pugh, 2004), as delivered in a UK secondary school. The impact of Paired Maths on the mathematics attainment of tutees, and the self-esteem of both tutees and tutors is evaluated.
Paired Maths involves pairs of students, one student in the role of a tutor and one in the role of a tutee, completing mathematics activities together. Tutors are trained to follow a structured process to scaffold their tutee's learning during the activities. Although existing theory and literature suggests that a cross-age, peer-tutoring intervention around mathematics could have a positive impact, no research has experimentally evaluated Paired Maths in the UK secondary school to date.
A total of 78 participants, aged 12-15 years, from three secondary schools situated in a small city in England took part. A Randomised Control Trial was used to consider the impact for Year 8 participants in the role of the Tutee. This compared children randomly assigned to either a Paired Maths (Experimental) Group, a Teaching Assistant Led Comparison Group or a Waitlist Control Group. Results showed no statistically significant differences between groups in mathematics attainment or self-esteem.
Within the same exploratory evaluation, a Randomised Control Trial was also employed to consider the impact for the Year 10 students in the role of the tutor. This compared children randomly assigned to either the Paired Maths (Experimental) group or a Waitlist Control Group. Although Waitlist Control participants saw a statistically significant decrease on measures of Maths self-concept over time, results showed no other statistically significant differences between groups in self-esteem.
Overall, Paired Maths was not considered to have had a positive impact on mathematics attainment for children in the role of the tutee, or on the self-esteem of children either in the role of tutee or tutor. These findings are considered in relation to the literature and methodology adopted, with a number of possible explanations presented. Possible avenues for future research are proposed (within and also beyond the post-positivist paradigm) with the key conclusion that further exploration is needed around what may support the successful implementation of a Paired Maths programme with secondary aged Pupils. Key limitations of the research relate to the measurement of the dependent variables and treatment fidelity
Are pilot trials useful for predicting randomisation and attrition rates in definitive studies: A review of publicly funded trials
BACKGROUND/AIMS: External pilot trials are recommended for testing the feasibility of main or confirmatory trials. However, there is little evidence that progress in external pilot trials actually predicts randomisation and attrition rates in the main trial. To assess the use of external pilot trials in trial design, we compared randomisation and attrition rates in publicly funded randomised controlled trials with rates in their pilots. METHODS: Randomised controlled trials for which there was an external pilot trial were identified from reports published between 2004 and 2013 in the Health Technology Assessment Journal. Data were extracted from published papers, protocols and reports. Bland-Altman plots and descriptive statistics were used to investigate the agreement of randomisation and attrition rates between the full and external pilot trials. RESULTS: Of 561 reports, 41 were randomised controlled trials with pilot trials and 16 met criteria for a pilot trial with sufficient data. Mean attrition and randomisation rates were 21.1% and 50.4%, respectively, in the pilot trials and 16.8% and 65.2% in the main. There was minimal bias in the pilot trial when predicting the main trial attrition and randomisation rate. However, the variation was large: the mean difference in the attrition rate between the pilot and main trial was -4.4% with limits of agreement of -37.1% to 28.2%. Limits of agreement for randomisation rates were -47.8% to 77.5%. CONCLUSION: Results from external pilot trials to estimate randomisation and attrition rates should be used with caution as comparison of the difference in the rates between pilots and their associated full trial demonstrates high variability. We suggest using internal pilot trials wherever appropriate
An O(N) symmetric extension of the Sine-Gordon Equation
We discuss an O(N) exension of the Sine-Gordon (S-G)equation which allows us
to perform an expansion around the leading order in large-N result using
Path-Integral methods. In leading order we show our methods agree with the
results of a variational calculation at large-N. We discuss the striking
differences for a non-polynomial interaction between the form for the effective
potential in the Gaussian approximation that one obtains at large-N when
compared to the N=1 case. This is in contrast to the case when the classical
potential is a polynomial in the field and no such drastic differences occur.
We find for our large-N extension of the Sine-Gordon model that the unbroken
ground state is unstable as one increases the coupling constant (as it is for
the original S-G equation) and we determine the stability criteria.Comment: 21 pages, Latex (Revtex4) v3:minor grammatical changes and addition
Civic‐led banishment in South Africa: punishment, authority, and spatialised precarity
Civic-led banishment, a fundamentally spatial punishment, is an understudied phenomenon in South Africa and beyond. We define it as “a punitive spatial practice, enacted by non-state actors in response to alleged criminality or deviance, which attempts varying degrees of socio-spatial expulsion over time”. This definition lays the framework for a socio-spatial analysis of punishment, and yields insights into the exercise of socio-spatial control in public and private space. We emphasise the specific challenges associated with banishment, together with the relationship between space, punishment, public authority, and sovereignty. We demonstrate how “negotiations” around banishment trade off two forms of intersecting precarity: those faced by residents in informal settlements and the potential precarity of public authorities. Finally, we argue that an exploration of all forms of punishment through the lens of socio-spatial expulsion enables us to tap into conversations around penal abolitionism
A cohort study of the associations between udder conformation, milk somatic cell count, and lamb weight in suckler ewes
A cohort study of 67 suckler ewes from 1 farm was carried out from January to May 2010 to investigate associations between udder conformation, udder half milk somatic cell count (SCC), and lamb weight. Ewes and lambs were observed at lambing. Ewe health and teat condition and lamb health and weight were recorded on 4 to 5 further occasions at 14-d intervals. At each observation, a milk sample was collected from each udder half for somatic cell counting. Two weeks after lambing, ewe udder conformation and teat placement were scored. Low lamb weight was associated with ewe SCC >400,000 cells/mL (−0.73kg), a new teat lesion 14 d previously (−0.91kg), suboptimal teat position (−1.38kg), rearing in a multiple litter (−1.45kg), presence of diarrhea at the examination (−1.19kg), and rearing by a 9-yr-old ewe compared with a 6-yr-old ewe (−2.36kg). High lamb weight was associated with increasing lamb age (0.21kg/d), increasing birth weight (1.65kg/kg at birth), and increasing number of days the ewe was given supplementary feed before lambing (0.06kg/d). High udder half SCC was associated with pendulous udders (9.6% increase in SCC/cm of drop) and greater total cross-sectional area of the teats (7.2% increase of SCC/cm2). Low SCC were associated with a heavier mean litter weight (6.7% decrease in SCC/kg). Linear, quadratic, and cubic terms for days in lactation were also significant. We conclude that poor udder and teat conformation are associated with high levels of intramammary infection, as indicated by increased SCC and that both physical attributes of the udder and SCC are linked to lamb growth, suggesting that selection of suckler ewes with better udder and teat conformation would reduce intramammary infection and increase lamb growth rate
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