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Volcanic eruptions, the El Nino Southern oscillation (ENSO), world population, and the world economy are the four variables usually discussed as influencing the short-run changes in CO2 atmospheric levels through their influence on CO2 emissions and sinks. Using proper procedures of detrending, we do not find any observable relation between the short-term growth of world population and the increase of CO2 concentrations. Results suggest that the link between volcanic eruptions, ENSO activity, and CO2 concentrations may be confounded by the coincidence of the Pinatubo eruption with the breakdown of the economies of the Soviet Bloc in the early 1990s. Changes in world GDP (WGDP) have a significant effect on CO2 concentrations, so that years of above-trend WGDP are years of greater rise of CO2 concentrations. Measuring WGDP in constant US dollars of 2000, for each trillion WGDP deviates from trend, the atmospheric CO2 concentration has deviated from trend, in the same direction, about half a part per million.

Parameter estimation in general state space models is not trivial as the likelihood is unknown. We propose a recursive estimator for general state space models, and show that the estimates converge to the true parameters with probability one. The estimates are also asymptotically Cramer-Rao efficient. The proposed estimator is easy to implement as it only relies on non-linear filtering. This makes the framework flexible as it is easy to tune the implementation to achieve computational efficiency. This is done by using the approximation of the score function derived from the theory on Iterative Filtering as a building block within the recursive maximum likelihood estimator.

We propose an infinitesimal dispersion index for Markov counting processes. We show that, under standard moment existence conditions, a process is infinitesimally (over-) equi-dispersed if, and only if, it is simple (compound), i.e. it increases in jumps of one (or more) unit(s), even though infinitesimally equi-dispersed processes might be under-, equi- or over-dispersed using previously studied indices. Compound processes arise, for example, when introducing continuous-time white noise to the rates of simple processes resulting in Levy-driven SDEs. We construct multivariate infinitesimally over-dispersed compartment models and queuing networks, suitable for applications where moment constraints inherent to simple processes do not hold., 26 pages

Health progress, as measured by the decline in mortality rates and the increase in life expectancy, is usually conceived as related to economic growth, especially in the long run. In this investigation it is shown that economic growth is positively associated with health progress in Sweden throughout the 19th century. However, the relation becomes weaker as time passes and is completely reversed in the second half of the 20th century, when economic growth negatively affects health progress. The effect of the economy on health occurs mostly at lag 0 in the 19th century and is lagged up to 2 years in the 20th century. No evidence is found for economic effects on mortality at greater lags. These findings are shown to be robustly consistent across a variety of statistical procedures, including linear regression, spectral analysis, cross-correlation, and lag regression models. Models using inflation and unemployment as economic indicators reveal similar results. Evidence for reverse effects of health progress on economic growth is weak, and unobservable in the second half of the 20th century.

Objective To determine the visual outcome and surgical complication rates of patients with isolated inherited congenital cataract. Design Retrospective noncomparative case series. Participants Patients and their families were ascertained from the genetic eye clinic and outpatient databases of Moorfields Eye Hospital, London, and invited to participate in the study. Four hundred twenty-two individuals from 72 pedigrees with this form of autosomal dominant cataract underwent ophthalmologic assessment. Main outcome measures Visual acuity and surgical complications (glaucoma, retinal detachment, amblyopia). Results In this study 49.4% of patients (46.8% of those operated) achieved a visual acuity (VA) of 20/40 or better, 35.9% (36.1% of those operated) a VA between 20/50 and 20/200, and 14.7% (17.1% of those operated) worse than 20/200. Opacities that were more diffuse or did not lie close to the visual axis were associated with a better prognosis for vision; 6.6% had glaucoma and 5.0% had retinal detachment develop. Conclusions Patients with isolated inherited congenital cataract have a better visual and surgical outcome than those with coexisting ocular and systemic abnormalities. The improved prognosis is related in part to the lack of other developmental abnormalities of the eye, and, because inherited cataracts are often partial at birth, surgery may be delayed to later infancy and childhood when there is a lower incidence of surgical complications and refractive correction is easier. Certain inherited phenotypes (lamellar, pulverulent, polymorphic, coralliform, and cortical) also seem to have a better prognosis, and this should be borne in mind when counseling these families. A large number of the patients in this study underwent surgery many years previously, when surgical outcomes were less favorable, and thus the results of this study establish only a minimum acuity dataset for the purposes of counseling.

Aims—To describe the clinical features of patients with a history of recurrent corneal epithelial erosion who develop acute corneal infiltration. Methods—The records were reviewed of patients who had previously been examined and treated for recurrent corneal epithelial erosion and who presented again with signs suggestive of a microbial keratitis. Results—11 patients were described; one patient presented with similar signs on two occasions. There was typically a paracentral epithelial defect >2 mm in diameter with an associated stromal infiltrate and an intense anterior uveitis. Three patients had a hypopyon, and four developed a subepithelial ring infiltrate. Samples were taken for microscopy and bacterial culture, with a positive isolate from two of 12 episodes (16%). Treatment with topical antibiotics and topical corticosteroid resulted in rapid reepithelialisation and a reduction of inflammation. There was good visual outcome for all eyes, with a recurrence or symptoms of epithelial erosion in only one eye after a mean follow up period of 18 months. Conclusions—Corneal infiltrates are an uncommon complication of recurrent corneal epithelial erosion. Despite the intensity of the infiltration the majority are culture negative using established techniques. There is typically rapid resolution and a good visual outcome, with a tendency for the episode to mark the end of further symptoms of epithelial erosion. (Br J Ophthalmol 1997;81:537‐540)

A general equivalence theorem is derived for vector fields invariant under Lie groups, which shows that they are not renormalizable unless the bare mass vanishes.

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