Mid-term results and factors affecting outcome of a metal-backed unicompartmental knee design: a case series.

BACKGROUND: Controversies exist regarding the indications for unicompartmental knee arthroplasty. The objective of this study is to report the mid-term results and examine predictors of failure in a metal-backed unicompartmental knee arthroplasty design. METHODS: At a mean follow-up of 60 months, 80 medial unicompartmental knee arthroplasties (68 patients) were evaluated. Implant survivorship was analyzed using Kaplan-Meier method. The Knee Society objective and functional scores and radiographic characteristics were compared before surgery and at final follow-up. A Cox proportional hazard model was used to examine the association of patient's age, gender, obesity (body mass index > 30 kg/m2), diagnosis, Knee Society scores and patella arthrosis with failure. RESULTS: There were 9 failures during the follow up. The mean Knee Society objective and functional scores were respectively 49 and 48 points preoperatively and 95 and 92 points postoperatively. The survival rate was 92% at 5 years and 84% at 10 years. The mean age was younger in the failure group than the non-failure group (p < 0.01). However, none of the factors assessed was independently associated with failure based on the results from the Cox proportional hazard model. CONCLUSION: Gender, pre-operative diagnosis, preoperative objective and functional scores and patellar osteophytes were not independent predictors of failure of unicompartmental knee implants, although high body mass index trended toward significance. The findings suggest that the standard criteria for UKA may be expanded without compromising the outcomes, although caution may be warranted in patients with very high body mass index pending additional data to confirm our results. LEVEL OF EVIDENCE: IV.

Continuous Plankton Records - Persistence In Time-Series Of Annual Means Of Abundance Of Zooplankton

Time-series of annual means of abundance of zooplankton of the north-east Atlantic Ocean and the North Sea, for the period 1948 to 1977, show considerable associations between successive years. The seasonal dynamics of the stocks appear to be consistent with at least a proportion of this being due to inherent persistence from year-to-year. Experiments with a simple model suggest that the observed properties of the time-series cannot be reproduced as a response to simple random forcing. The extent of trends and long wavelength variations can be simulated by introducing fairly extensive persistence into the perturbations, but this underestimates the extent of shorter wavelength variability in the observed time-series. The effect of persistence is to increase the proportion of trend and long wavelength variability in time-series of annual means, but stocks can respond to short wavelength perturbations provided these have a clearly defined frequency.

Coccolithophore surface distributions in the North Atlantic and their modulation of the air-sea flux of CO2 from 10 years of satellite Earth observation data

Coccolithophores are the primary oceanic phytoplankton responsible for the production of calcium carbonate (CaCO3). These climatically important plankton play a key role in the oceanic carbon cycle as a major contributor of carbon to the open ocean carbonate pump (similar to 50 %) and their calcification can affect the atmosphere-to-ocean (air-sea) uptake of carbon dioxide (CO2) through increasing the seawater partial pressure of CO2 (pCO(2)). Here we document variations in the areal extent of surface blooms of the globally important coccolithophore, Emiliania huxleyi, in the North Atlantic over a 10-year period (1998-2007), using Earth observation data from the Sea-viewing Wide Field-of-view Sensor (SeaWiFS). We calculate the annual mean sea surface areal coverage of E. huxleyi in the North Atlantic to be 474 000 +/- 104 000 km(2), which results in a net CaCO3 carbon (CaCO3-C) production of 0.14-1.71 Tg CaCO3-C per year. However, this surface coverage (and, thus, net production) can fluctuate inter-annually by -54/+81% about the mean value and is strongly correlated with the El Nino/Southern Oscillation (ENSO) climate oscillation index (r = 0.75, p < 0.02). Our analysis evaluates the spatial extent over which the E. huxleyi blooms in the North Atlantic can increase the pCO(2) and, thus, decrease the localised air-sea flux of atmospheric CO2. In regions where the blooms are prevalent, the average reduction in the monthly air-sea CO2 flux can reach 55%. The maximum reduction of the monthly air-sea CO2 flux in the time series is 155 %. This work suggests that the high variability, frequency and distribution of these calcifying plankton and their impact on pCO(2) should be considered if we are to fully understand the variability of the North Atlantic air-to-sea flux of CO2. We estimate that these blooms can reduce the annual N. Atlantic net sink atmospheric CO2 by between 3-28 %.

Comparing copepod time-series in the north of Spain: Spatial autocorrelation of community composition

Four time-series of copepod species biomass in the north of Spain were contrasted to demonstrate spatial autocorrelation of local communities and their responses to short-term local and regional variability in oceanographic conditions. The series represented coastal and oceanic environments along a marked gradient of influence of seasonal upwelling from Galicia to the Mar Cantábrico (S Bay of Biscay), and each one included at least 10 years of continuous data collected at monthly frequency. Community composition (i.e. species number and diversity) was very consistent through the region, but local variations in the presence of new species and the relative proportions of common species allowed for the characterisation of the response to the environment at each site. Small-sized species were more frequent near the coast. A few species, however, captured the main patterns of variability in all series. Calanus helgolandicus and Acartia (mainly Acartia clausi) were generally the main contributors to total biomass, while other species as Paracalanus parvus and Clausocalanus spp. were important only at some locations. Most copepod indices were positively correlated with upwelling, either considering the whole community (biomass, species richness and diversity) or individual species, but only in the coastal series analysed since 1991. Copepods in the nearby ocean, however, showed negative correlations with upwelling in the period 1960–1986. The effects of upwelling may have been modulated by local factors, as showed by the increases in biomass, number of species and diversity in associations with increases in sea surface temperature in Galicia, while in the Mar Cantábrico only the warming-tolerant species increased and those typical of upwelling decreased. Density stratification of the water column was associated with decreases in total copepod biomass in Galicia, while it favoured the increase in species richness in the Mar Cantábrico. Nearly all significant responses of copepods to environmental variability were delayed by up to 5 months, showing the importance of considering time-lags in the analysis of temporal responses of zooplankton.

A comparison of two zooplankton time series data collected in the Gulf of Maine

Interannual and seasonal trends of zooplankton abundance and species composition were compared between the Bongo net and Continuous Plankton Recorder (CPR) time series in the Gulf of Maine. Data from 5799 Bongo and 3118 CPR samples were compared from the years 1978–2006. The two programs use different sampling methods, with the Bongo time series composed of bimonthly vertically integrated samples from locations throughout the region, while the CPR was towed monthly at 10 m depth on a transect that bisects the region. It was found that there was a significant correlation between the interannual (r = 0.67, P < 0.01) and seasonal (r = 0.95, P < 0.01) variability of total zooplankton counts. Abundance rankings of individual taxa were highly correlated and temporal trends of dominant copepods were similar between samplers. Multivariate analysis also showed that both time series equally detected major shifts in community structure through time. However, absolute abundance levels were higher in the Bongo and temporal patterns for many of the less abundant taxa groups were not similar between the two devices. The different mesh sizes of the samplers probably caused some of the discrepancies; but diel migration patterns, damage to soft bodied animals and avoidance of the small CPR aperture by some taxa likely contributed to the catch differences between the two devices. Nonetheless, Bongo data presented here confirm the previously published patterns found in the CPR data set, and both show that the abundance increase of the 1990s has been followed by average to below average levels from 2002 to 06.

Covariance among North Sea ecosystem state indicators during the past 50 years - contrasts between coastal and open waters

Regime shift and principal component analysis of a spatially disaggregated database capturing time-series of climatic, nutrient and plankton variables in the North Sea revealed considerable covariance between groups of ecosystem indicators. Plankton and climate time-series span the period 1958–2003, those of nutrients start in 1980. In both regions, the period from 1989 to 2001 identified in principal component 1 had warmer surface waters, higher Atlantic inflow and stronger winds, than the periods before or after. However, it was preceded by a regime shift in both open (PC2) and coastal (PC3) waters during 1977 towards more hours of sunlight and higher water temperature, which lasted until 1997. The relative influence of nutrient availability and climatic forcing differed between open and coastal North Sea regions. Inter-annual variability in phytoplankton dynamics of the open North Sea was primarily regulated by climatic forcing, specifically by sea surface temperature, Atlantic inflow and co-varying wind stress and NAO. Coastal phytoplankton variability, however, was regulated by insolation and sea surface temperature, as well as Si availability, but not by N or P. Regime shifts in principal components of hydrographic and climatic variables (explaining 55 and 61% of the variance in coastal and open water variables) were detected using Rodionov's sequential t-test. These shifts in hydroclimatic variables which occurred around 1977, 1989, 1997 and 2001, were synchronized in open and coastal waters, and were tracked by open water chlorophyll and copepods, but not by coastal plankton. North–central–south or open-coastal spatial breakdowns of the North Sea explained similar amounts of variability in most ecosystem indicators with the exception of diatom abundance and chlorophyll concentration, which were clearly better explained using the open-coastal configuration.

Coccolithophore surface distributions in the North Atlantic and their modulation of the air-sea flux of CO2 from 10 years of satellite Earth observation data

Coccolithophores are the primary oceanic phytoplankton responsible for the production of calcium carbonate (CaCO3). These climatically important plankton play a key role in the oceanic carbon cycle as a major contributor of carbon to the open ocean 5 carbonate pump (�50%) and their formation can affect the atmosphere-to-ocean (airsea) uptake of carbon dioxide (CO2) through increasing the seawater partial pressure of CO2 (pCO2). Here we document variations in the areal extent of surface blooms of the globally important coccolithophore, Emiliania huxleyi, in the North Atlantic over a 10-year period (1998–2007), using Earth observation data from the Sea-viewing Wide 10 Field of view Sensor (SeaWiFS).We calculate the annual mean surface areal coverage of E. huxleyi in the North Atlantic to be 474 000±119 000km2 yr−1, which results in a net CaCO3 production of 0.62±0.15 Tg CaCO3 carbon per year. However, this surface coverage and net production can fluctuate by −54/+81% about these mean values and are strongly correlated with the El Ni˜no/Southern Oscillation (ENSO) climate os15 cillation index (r =0.75, p<0.02). Our analysis evaluates the spatial extent over which the E. huxleyi blooms in the North Atlantic can increase the pCO2 and thus decrease the localised sink of atmospheric CO2. In regions where the blooms are prevalent, the average reduction in the monthly CO2 sink can reach 12 %. The maximum reduction of the monthly CO2 sink in the time series is 32 %. This work suggests that the high 20 variability, frequency and distribution of these calcifying plankton and their impact on pCO2 should be considered within modelling studies of the North Atlantic if we are to fully understand the variability of its air-to-sea CO2 flux.

How does Calanus helgolandicus maintain its population in a variable environment? Analysis of a 25-year time series from the English Channel

Calanus helgolandicus is a key copepod of the NE Atlantic and fringing shelves, with a distribution that is expanding northwards with oceanic warming. The Plymouth L4 site has warmed over the past 25-years, and experiences large variations in the timing and availability of food for C. helgolandicus. Here we examine the degree to which these changes translate into variation in reproductive output and subsequently C. helgolandicus population size. Egg production rates (eggs female−1 day−1) were maximal in the spring to early-summer period of diatom blooms and high ciliate abundance, rather than during the equally large autumn blooms of autotrophic dinoflagellates. Egg hatch success was lower in spring however, with a greater proportion of naupliar deformities then also. Both the timing and the mean summer abundance of C. helgolandicus (CI–CVI) reflected those of spring total reproductive output. However this relationship was driven by inter-annual variability in female abundance and not that of egg production per female, which ranged only two-fold. Winter abundance of C. helgolandicus at L4 was much more variable than abundance in other seasons, and reflected conditions from the previous growing season. However, these low winter abundances had no clear carry-over signal to the following season’s population size. Overall, the C. helgolandicus population appears to be surprisingly resilient at this dynamic, inshore site, showing no long-term phenology shift and only a four-fold variation in mean abundance between years. This dampening effect may reflect a series of mortality sources, associated with the timing of stratification in the early part of the season, likely affecting egg sinking and loss, plus intense, density-dependent mortality of early stages in mid-summer likely through predation.

Breaking the boundaries: Geographical approaches to integrating 200 years of the Census

The census and similar sources of data have been published for two centuries so the information that they contain should provide an unparalleled insight into the changing population of Britain over this time period. To date, however, the seemingly trivial problem of changes in boundaries has seriously hampered the use of these sources as they make it impossible to create long run time series of spatially detailed data. The paper reviews methodologies that attempt to resolve this problem by using geographical information systems and areal inter-polation to allow the reallocation of data from one set of administrative units onto another. This makes it possible to examine change over time for a standard geography and thus it becomes possible to unlock the spatial detail and the temporal depth that are held in the census and in related sources.

Natural history of idiopathic erythrocytosis - A retrospective case series review

Idiopathic Erythrocytosis (IE) is a diagnosis given to patients who have an absolute erythrocytosis (red cell mass more than 25% above their mean normal predicted value) but who do not have a known form of primary or secondary erythrocytosis (BCSH guideline, 2005). We report here the results of a follow-up study of 80 patients (44 male and 36 female) diagnosed with IE from the United Kingdom and the Republic of Ireland over a 10 year period. Baseline information was initially collected when investigating for molecular causes of erythrocytosis in this group. The diagnosis of IE was made on the basis of a raised red cell mass >25% above mean normal predicted value, absence of Polycythaemia Vera (PV) based on the criteria of Pearson and Messinezy (1996), and the exclusion of secondary erythrocytosis (oxygen saturation >92% on pulse oximetry, no history of sleep apnoea, no renal or hepatic pathology, and a normal oxygen dissociation curve (if indicated). The average age at diagnosis of erythrocytosis was 34.5 (2–74 years). Erythropoietin levels were available for 77/80 of the patients and were low in 18 (23%) and normal or high in 59 (74%). Ultrasound imaging was carried out in 67 patients (84%) at time of diagnosis and no significant abnormalities found. Fourteen patients had a family history of erythrocytosis. These patients have now been followed up for an average of 9.4 years (range 1–39). Out of 80 patients 56 patients can still be classified as having IE, of whom 52 are living (cause of death in the other 4 - lung cancer, RTA, sepsis, unknown). Thirty-five of these patients are regularly venesected, 3 take hydroxyurea (one also venesected), 11 receive no treatment while treatment is unknown in 2. Twenty take aspirin, 1 warfarin and 31 no thromboprophylaxis. Four of these patients had suffered thromboembolic complications (3 with CVA/TIAs and 1 with recurrent DVT) at or before their original diagnosis. Since diagnosis 8 patients have had 9 thrombotic events of which 7 were arterial (1 CVA, 3 TIAs, 1 MI, 2 PVD) and 2 venous (DVT/PE). Twenty take aspirin, 1 dipyridamole, 1 warfarin and 30 take no thromboprophylaxis. Out of the 24 patients who now have a diagnosis other than IE, 8 have been diagnosed with myelo-proliferative disease. Thirteen patients have a molecular abnormality which is likely to account for their erythrocytosis (11 VHL, 1 PHD-2, 1 EPO-receptor mutations). Three patients have secondary erythrocytosis. Older case studies identified a heterogenous group of patients, some of whom probably had apparent erythrocytosis and some who had either primary polycythaemia or secondary causes later identified (Modan and Modan, Najean et al). More recent reviews have identified a more homogenous group with low rates of transformation to myelofibrosis/acute leukaemia and low rates of thrombosis of around 1% patient-year. Follow up of our initial patient group does indeed reveal a heterogeneous group of patients with 10% now diagnosed with an MPD, although when analysis is confined to those patients who continue to fulfil the criteria for IE, the clinical course has been more stable. There has been no progression to MDS or leukaemia in this group (one patient with PV progressed to AML). The rate of thrombosis is 1.6% patient-years which is lower than the rate seen in PV and is consistent with the rate identified in other series. Molecular defects continue to be identified in this group and future investigation is likely to reveal further abnormalities.

Fluoroscopic and electrical assessment of a series of defibrillation leads:prevalence of externalized conductors

Introduction : Insulation defects with externalized conductors have been reported in the St. Jude Riata(®) family of defibrillation leads (St. Jude Medical, Sylmar, CA, USA). The objective of the Northern Ireland Riata(®) lead screening program was to identify insulation defects and externalized conductors by systematic fluoroscopic and electrical assessment in a prospectively defined cohort of patients. We sought to estimate the prevalence, identify risk factors, and determine the natural history of this abnormality. Methods : All patients with a Riata(®) lead under follow-up at the Royal Victoria Hospital were invited for fluoroscopic imaging and implantable cardioverter-defibrillator lead parameter checks. Fluoroscopic images were read independently by two cardiologists and the presence of externalized conductors was classified as positive, negative, or borderline. Results: One hundred and sixty-five of 212 patients with a Riata lead were evaluated by fluoroscopy and lead parameter measurements. The mean duration after implantation was 3.98+/-1.43 years. After screening 25 (15%) patients were classified as positive, 137 (83%) negative, and three (1.8%) borderline. Time since implantation (P = 0.001), presence of a single coil lead (P = 0.042), and patient age (P = 0.034) were significantly associated with externalized conductors. The observed rate of externalized conductors was 26.9% for 8-French and 4.7% for 7-French leads. No leads that were identified prospectively with externalized conductors had electrical abnormalities. Seven of 25 (28%) patients had a defective lead extracted by the end of this screening period. Conclusion: A significant proportion (15%) of patients with a Riata lead had an insulation breach 4 years after implantation. High-resolution fluoroscopic imaging in at least two orthogonal views is required to identify this abnormality. (PACE 2012;35:1498-1504).

Transnational Fantômas: The Influence of Feuillade’s Series on International Cinema during the 1910s

The influence of Fantômas novels and films on global popular culture is widely acknowledged. From the 1915 Spanish musical "Cine-fantomas" to the 1960s Italian comic book series "Diabolik," "Kriminal" and "Satanik," from Turkish B-movies such as "Fantoma Istanbulda Bulusalim" (dir. Natuk Baytan, 1967) to Julio Cortazar’s anti-imperialist pamphlet "Fantômas contra los vampiros multinacionales" (1975), Pierre Souvestre and Marcel Allain’s original literary series have engendered uncountable translations, adaptations, imitations and plagiarisms that have spread the character’s fame worldwide since its first appearance in 1911.
By focusing on the influence of Louis Feuillade’s film adaptations during the first decade of Fantômas’ long history as a transnational and transmedia icon, this paper aims to contribute to the growing interdisciplinary field that deals with the history of the supranational cultural sphere created by modern media culture. As a sort of archaeology of contemporary cultural globalization, this form of study intends to enrich previous historical surveys that had only taken into consideration specific national contexts. Moreover, it might also rebalance certain “colonizing” accounts that overemphasize the role of the cultural superpowers such as France, the UK or the US, often forgetting the appropriation of the products of international popular culture to be found in other countries. Therefore, this paper examines the transnational circulation of Fantômas films and, in particular, the creative processes engendered outside of France their origin country. As a controversial character and a central player in the relationship between cinema and literature in the crucial years when the feature and serial film boosted and legitimized the film industry, Fantômas represents an exemplary case study to discuss the cross-cultural and cross-media dynamics engendered by popular fiction.

Transnational connections in European crime film series (1908–1914)

This article addresses the issue of ‘European popular cinema’ by discussing a very specific phenomenon, i.e. the crime series produced in the years immediately preceding World War I (e.g. Victorin Jasset’s Nick Carter, Viggo Larsen’s Arsène Lupin contra Sherlock, Ubaldo Maria del Colle’s Raffles, il ladro misterioso, Louis Feuillade’s Fantômas, George Pearson’s Ultus). On the one hand, the transnational circulation of these films is seen as the result of the development of the European cultural industries since the late nineteenth century; on the other hand, the rapid decline of this genre testifies of the historical peculiarity of this production. In particular, the popular heroic figure of the ‘gentleman thief’ seems to express at the same time the liberating, anti-hierarchial ethos of modernization and the dream of a quiet conciliation of the new and the traditional values: as a consequence, it might be regarded as a telling example of the economical, social and ideological transformations of that crucial phase in European history, when the development of the second industrial revolution and the first phase of ‘globalization’ pointed at the birth of a supranational sphere before the outbreak of World War I, which would temporarily stop this process.

The incidence and rate of rhegmatogenous retinal detachment seven years after cataract surgery in patients with high myopia

Background: Cataract extraction is the most commonly performed surgery in the National Health Service. Myopia increases the risk of postoperative rhegmatogenous retinal detachment (RRD). The aim of this study was to determine the incidence and rate of RRD seven years after cataract extraction in highly myopic eyes. Methods: Retrospective review was performed of notes of all high myopes (axial length 26.0 mm or more) who underwent cataract extraction during the study period in one centre. Results: 84 eyes met the study criteria. Follow-up time from surgery was 93 to 147 months (median 127 months). The average axial length was 28.72 mm (sd 1.37). Two eyes developed post-operative RRD; the incidence was 2.4% and the rate one RRD per 441.6 person-years. The results of 15 other studies on the incidence of RRD after cataract extraction in high myopia were pooled and combined with our estimate. Conclusion: Both patients in our study who developed RRD had risk factors for this complication as well as high myopia. Risk factors are discussed in the light of our results and the pooled estimate. Our follow-up time is longer than most. Future case series should calculate rates to allow meaningful comparison of case series. © The Ulster Medical Society, 2009.