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Michel Callon has conceptualised economic actors as made up of socio‐technical agencements: collectives of human beings, technical devices, algorithms, and so on. This article reports a pilot, partially observational study of a hedge fund, a category of actor in financial markets that is of growing importance but that has so far attracted little attention in economic sociology. It draws on that study, and on interviews with other financial market practitioners, to delineate what is involved in viewing such an actor as made up of an agencement, and discusses the merits of doing so.

We have prospectively validated the influence of tumor-related and patient-related factors. Margin involvement and the preoperative mGPS were the most important determinants of overall survival in patients undergoing potentially curative pancreaticoduodenectomy. Furthermore, both had independent prognostic value in those patients receiving adjuvant chemotherapy. In the future, this may be considered a stratification factor for entry onto therapeutic trials.

Objectives:The temporomandibular joint is occasionally encountered in extirpative surgery of the head and neck. It presents a difficult management issue. Little has been reported on functional outcomes after resection and reconstruction of the temporomandibular joint. Design: A retrospective analysis consisting of chart reviews and phone interviews was performed on 17 patients who underwent fibular free flap reconstruction of the temporomandibular joint from 1993 to 1998. Results: Mean follow-up in surviving patients (10) was 41.3 months. Mean age of the group was 62; male-to-female ratio was 11:6. Average hospital stay was 11.6 days. Four patients had no radiation therapy, 2 had preoperative and 11 had postoperative treatment. Five patients had one osteotomy, seven had two, one had three, and one had four. Ten patients could chew, one could not, and none were recorded for the remaining. Diet consisted of regular food for two patients, soft food for seven, full liquids for four, and tube feeds for four. Cosmesis was judged as excellent by eight patients, acceptable by two, and unacceptable by two. Five patients did not describe cosmesis. Most patients stated that bony contour was excellent, but that the soft tissue defect was noticeable. Speech was judged as intelligible by seven and moderately understandable by one. Nine patients did not describe speech. Two patients had postoperative displacement of the fibular head out of the fossa. Conclusion: Primary reconstruction of the temporomandibular joint with microvascular fibular flaps is a viable and effective means of restoring function. The majority of patients are able to resume oral feeds, obtain excellent or pleasing cosmetic results, and maintain intelligible speech.Laryngoscope, 110:977-981, 2000

The aim of this study was to determine whether the Nd:YAG laser energies of 50 and 80 mJ at 10 pulses per second (pps) were capable of improving the clinical parameters associated with periodontal disease. These energy settings were chosen as previous work indicated that higher values would damage root surfaces and that 80 mJ had an in-vitro bactericidal effect. Eighty periodontally affected sites in teeth scheduled for extraction from 11 patients with adult periodontitis were randomly placed in one of the following four treatment groups: 1. laser treatment at 50 mJ, 10 pps for 3 minutes; 2. laser treatment at 80 mJ, 10 pps for 3 minutes; 3. scaling and 4. untreated control. Probing depth, bleeding on probing (BOP), plaque index, gingival index and gingival crevicular fluid (GCF) volume were measured at baseline and week 6. Baseline subgingival microbiological samples were collected, then repeated immediately after treatment and at week 6 to assess the total anaerobic colony forming units (CFU). Only the scaling group showed a significant reduction in pocket depth and BOP (P < 0.001). The microbial samples taken immediately after scaling and laser at 80 mJ and 10 pps treatments showed a significant reduction in total CFU compared with the baseline (P < 0.01), which was sustained only in the scaling group until week 6. Electron microscopy did not reveal any heat damage on the root surfaces. This study demonstrated that application of Nd:YAG laser pulses of 50 mJ and 80 mJ failed to improve the clinical and microbiological parameters of periodontal disease.

Drawing on documentary sources and 114 interviews with market participants, this and a companion article discuss the development and use in finance of the Gaussian copula family of models, which are employed to estimate the probability distribution of losses on a pool of loans or bonds, and which were centrally involved in the credit crisis. This article, which explores how and why the Gaussian copula family developed in the way it did, employs the concept of 'evaluation culture', a set of practices, preferences and beliefs concerning how to determine the economic value of financial instruments that is shared by members of multiple organizations. We identify an evaluation culture, dominant within the derivatives departments of investment banks, which we call the 'culture of no-arbitrage modelling', and explore its relation to the development of Gaussian copula models. The article suggests that two themes from the science and technology studies literature on models (modelling as 'impure' bricolage, and modelling as articulating with heterogeneous objectives and constraints) help elucidate the history of Gaussian copula models in finance.

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