Need for standardization of the measurement of preoperative weight in bariatric surgical patients in the UK: A survey of British Obesity and Metabolic Surgery Society (BOMSS) members

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Darkness visible: reflections on underground ecology

1 Soil science and ecology have developed independently, making it difficult for ecologists to contribute to urgent current debates on the destruction of the global soil resource and its key role in the global carbon cycle. Soils are believed to be exceptionally biodiverse parts of ecosystems, a view confirmed by recent data from the UK Soil Biodiversity Programme at Sourhope, Scotland, where high diversity was a characteristic of small organisms, but not of larger ones. Explaining this difference requires knowledge that we currently lack about the basic biology and biogeography of micro-organisms. 2 It seems inherently plausible that the high levels of biological diversity in soil play some part in determining the ability of soils to undertake ecosystem-level processes, such as carbon and mineral cycling. However, we lack conceptual models to address this issue, and debate about the role of biodiversity in ecosystem processes has centred around the concept of functional redundancy, and has consequently been largely semantic. More precise construction of our experimental questions is needed to advance understanding. 3 These issues are well illustrated by the fungi that form arbuscular mycorrhizas, the Glomeromycota. This ancient symbiosis of plants and fungi is responsible for phosphate uptake in most land plants, and the phylum is generally held to be species-poor and non-specific, with most members readily colonizing any plant species. Molecular techniques have shown both those assumptions to be unsafe, raising questions about what factors have promoted diversification in these fungi. One source of this genetic diversity may be functional diversity. 4 Specificity of the mycorrhizal interaction between plants and fungi would have important ecosystem consequences. One example would be in the control of invasiveness in introduced plant species: surprisingly, naturalized plant species in Britain are disproportionately from mycorrhizal families, suggesting that these fungi may play a role in assisting invasion. 5 What emerges from an attempt to relate biodiversity and ecosystem processes in soil is our extraordinary ignorance about the organisms involved. There are fundamental questions that are now answerable with new techniques and sufficient will, such as how biodiverse are natural soils? Do microbes have biogeography? Are there rare or even endangered microbes

Size Doesn't Matter: Towards a More Inclusive Philosophy of Biology

notes: As the primary author, O’Malley drafted the paper, and gathered and analysed data (scientific papers and talks). Conceptual analysis was conducted by both authors.publication-status: Publishedtypes: ArticlePhilosophers of biology, along with everyone else, generally perceive life to fall into two broad categories, the microbes and macrobes, and then pay most of their attention to the latter. ‘Macrobe’ is the word we propose for larger life forms, and we use it as part of an argument for microbial equality. We suggest that taking more notice of microbes – the dominant life form on the planet, both now and throughout evolutionary history – will transform some of the philosophy of biology’s standard ideas on ontology, evolution, taxonomy and biodiversity. We set out a number of recent developments in microbiology – including biofilm formation, chemotaxis, quorum sensing and gene transfer – that highlight microbial capacities for cooperation and communication and break down conventional thinking that microbes are solely or primarily single-celled organisms. These insights also bring new perspectives to the levels of selection debate, as well as to discussions of the evolution and nature of multicellularity, and to neo-Darwinian understandings of evolutionary mechanisms. We show how these revisions lead to further complications for microbial classification and the philosophies of systematics and biodiversity. Incorporating microbial insights into the philosophy of biology will challenge many of its assumptions, but also give greater scope and depth to its investigations

The Cholecystectomy As A Day Case (CAAD) Score: A Validated Score of Preoperative Predictors of Successful Day-Case Cholecystectomy Using the CholeS Data Set

Background Day-case surgery is associated with significant patient and cost benefits. However, only 43% of cholecystectomy patients are discharged home the same day. One hypothesis is day-case cholecystectomy rates, defined as patients discharged the same day as their operation, may be improved by better assessment of patients using standard preoperative variables. Methods Data were extracted from a prospectively collected data set of cholecystectomy patients from 166 UK and Irish hospitals (CholeS). Cholecystectomies performed as elective procedures were divided into main (75%) and validation (25%) data sets. Preoperative predictors were identified, and a risk score of failed day case was devised using multivariate logistic regression. Receiver operating curve analysis was used to validate the score in the validation data set. Results Of the 7426 elective cholecystectomies performed, 49% of these were discharged home the same day. Same-day discharge following cholecystectomy was less likely with older patients (OR 0.18, 95% CI 0.15–0.23), higher ASA scores (OR 0.19, 95% CI 0.15–0.23), complicated cholelithiasis (OR 0.38, 95% CI 0.31 to 0.48), male gender (OR 0.66, 95% CI 0.58–0.74), previous acute gallstone-related admissions (OR 0.54, 95% CI 0.48–0.60) and preoperative endoscopic intervention (OR 0.40, 95% CI 0.34–0.47). The CAAD score was developed using these variables. When applied to the validation subgroup, a CAAD score of ≤5 was associated with 80.8% successful day-case cholecystectomy compared with 19.2% associated with a CAAD score >5 (p < 0.001). Conclusions The CAAD score which utilises data readily available from clinic letters and electronic sources can predict same-day discharges following cholecystectomy

The structure and function of the vegetative mycelium of ectomycorrhizal plants .4. Qualitative-analysis of carbohydrate contents of mycelium interconnecting host plants

Plants of Pinus spp. were grown in observation chambers with the mycorrhizal fungi Suillus bovinus, Pisolithus tinctorius or Paxillus involutus. After interconnecting mycelial systems had developed between plants, individual hosts in some chambers of each species were fed with 14CO2. Mycelia from radioactively labelled and unlabelled chambers were harvested and their carbohydrates were extracted, separated chromatographically and identified. The major carbohydrates in all of the fungi were trehalose, mannitol and arabitol, their relative proportions differing in the different fungi. The results are discussed in relation both to carbon nutrition of the fungus and to carbon transfer between interconnected plants

The structure and function of the vegetative mycelium of ectomycorrhizal plants .3. Ultrastructural and autoradiographic analysis of inter-plant carbon distribution through intact mycelial systems

Plants of Pinus sylvestris L. were grown in mycorrhizal association with Suillus bovinus (Fr.) O. Kuntze in observation chambers until an interconnecting mycelial network had developed between the seedlings. The shoot of an individual seedling was then sealed in a perspex cuvette and exposed to 14CO2. After incubation for 48 h, the 'donor' shoot was removed and components of the mycelial network and mycorrhizal roots of connected and unconnected 'receiver' seedlings were harvested, fixed, embedded and sectioned prior to being autoradiographed and examined by transmission electron microscopy. The patterns of distribution of 14C-labelled material within the mycelial strands, the sheath and root tissues was examined. The results are discussed in relation to carbon metabolism of the fungus and of the interconnected host plant

Effect of microgeometry on switching and transport in lead zirconate titanate capacitors: Implications for etching of nano-ferroelectrics

We evaluate different switching behaviors of lead zirconate titanate (PZT) thin film capacitors with two different geometries: one, a square 100x100 mum; the second, a ribbon (1.6 mum width but with approximately the same total area), as a function of temperature T, and applied electric field E. The ribbon capacitor shows a stronger dependence (by ca. 70%) of activation field on T and E. This is interpreted as a chemical reduction of edge material in the long-perimeter ribbons due to plasma etching. In order to understand and model the different domain switching of these two types of PZT capacitor, we also investigate impedance spectra at various temperatures from 27 to 470 degreesC. From ac conductance spectra, both square- and ribbon-type capacitors have similar trap levels, 0.38+/-0.02 eV. From analysis of conductivity spectra, we find that the ribbon capacitor contains an additional 0.19+/-0.02 eV trap level attributed to H-O dipoles due to hydrogen reduction; the latter trap results in domain pinning, which is interpreted as the origin of the relatively strong dependence of the activation field on T and E in the ribbons compared to the square capacitors. The additional loss peak in the ribbon capacitors is also observed in real cell-type capacitors, but only when their edge/area ratio becomes large, as in submicron cells for megabit scale. (C) 2004 American Institute of Physics.</p

Intra-abdominal packing for uncontrollable haemorrhage during ruptured abdominal aortic aneurysm repair

Objective: Intra-abdominal packing is a valuable adjunct in patients with abdominal trauma and uncontrollable bleeding but few data exist regarding early and late outcome associated with this technique in patients with ruptured abdominal aortic aneurysm (AAA). Methods: Interrogation of a prospective vascular surgical database identified 23 patients (22 men; median age 69, range 59–82, years) with ruptured AAA who required intra-abdominal packing for control of coagulopathic haemorrhage after insertion of an aortic graft between January 1982 and December 2003. Co-morbidity, operative and outcome data were retrieved. Results: Haemostasis was achieved and packs were removed within 48 h in 20 patients. In those patients who had a graft inserted, the peri-operative mortality rate was 12 of 23 (52%) patients (vs. 172 of 455 (38%) patients who were not packed, NS). Three (13%) patients developed early intra-abdominal sepsis, which was universally fatal: graft-enteric fistula, intra-abdominal abscess with necrotizing fasciitis of the abdominal wound, and infected retroperitoneal haematoma. Two of 11 (18%) survivors developed late graft-related infective complications: major aortic graft infection at 6 months and symptomatic infected para-anastomotic aortic false aneurysm at 39 months. Early and late intra-abdominal infective complications were significantly more common in patients who were packed than in those who were not (packed: five of 23, 22% vs. non-packed: five of 455, 1%; p<0.001). Conclusion: These data demonstrate that intra-abdominal packing in coagulopathic patients with ruptured AAA can achieve an acceptable survival rate. However, this technique may be associated with an increased incidence of early and late intra-abdominal infective complications.D.J. Adam, R.A. Fitridge and S. Rapti