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Purpose. To determine whether a change in prophylactic antibiotic protocol for orthopaedic surgeries may reduce the frequency of Clostridium difficile–associated diarrhoeal infections. Methods. Records of 1331 patients who underwent trauma or elective surgeries involving implantation of metalwork were reviewed. 231 trauma and 394 elective patients who received intravenous cefuroxime–based antibiotic prophylaxis between August 2006 and January 2007 were compared with 216 trauma and 490 elective patients who received a single dose of gentamicin and flucloxacillin or teicoplanin for antibiotic prophylaxis between August 2007 and January 2008. Diarrhoeal faecal specimens of 148 (33%) trauma patients and 106 (12%) elective patients were examined. The outcome variables were the rates of C difficile infection and early deep wound infection. Results. There were 32 cases of C difficile–associated diarrhoeal infection and 28 cases of early deep wound infection. The frequency of C difficile–associated diarrhoeal infection decreased after use of the new antibiotic protocol (from 4 to 1%, p=0.004), particularly in the trauma patients (from 8 to 3%, p=0.02); in the elective patients the difference was not significant (from 1 to 0.5%, p=0.27). The change of antibiotic protocol did not significantly affect the incidence of deep wound infections in the trauma (p=0.46) or elective (p=0.90) patients. The rate of C difficile infection was 8-fold higher in the trauma than elective patients, both before and after the change of protocol. Conclusion. Changing antibiotic protocol is one way of reducing the incidence of C difficile–associated diarrhoeal infections in orthopaedic patients, without increasing the rate of deep wound infections.

Differentially substituted 1,3-diaryl-substituted allylic cations generated by ionization of the corresponding allylic alcohols in the presence of a Lewis acid undergo chemoselective and regioselective electrocyclization reactions to generate 1-aryl-1H-indenes. Electrocyclization only occurs for allylic cations bearing a 2-substituent, with 2-ester and 2-alkyl substituents both tolerated. In general, the presence of electron-withdrawing substituents deactivates the ring and disfavors cyclization. In contrast, the selectivity of cyclization of systems containing electron-donating substituents depends on the nature and position of the electron-donating group. Electron-donating substituents at the meta position particularly favor cyclization. There was no obvious correlation of cyclization selectivity with calculated electron densities as has been suggested for electrophilic aromatic substitution reactions. However, the calculated selectivities determined by a gas-phase (B3LYP/6-31G* + ZPVE) comparison of the relative rates of cyclization were in remarkably good agreement with the observed selectivities. Calculated transition-state structures for cyclization are consistent with a cationic pi4(a) conrotatory electrocyclization mechanism. In some cases involving more electron-deficient systems, the initially formed 1H-indene underwent subsequent alkene isomerization to the 3H-indene. In one example, an unusual dimerization reaction occurred to give a cyclopenta[a]indene via an unusual formal cationic 2pi+2pi cycloaddition of the allylic cation with the intermediate indene.

Generally, the hetero-Diels-Alder reaction (Povarov reaction) of N-arylimine dienes are limited to reaction with activated, electron-rich alkenes. However, introduction of ring strain in the dienophile, as with moderately strained bicyclo[2.2.1]heptenes (norbornene), enables three-component Povarov reaction with in situ formed N-arylimines under Lewis acid catalyzed conditions (BF(3).OEt(2)). The reactions proceed efficiently with a diverse set of commercially available anilines and benzaldehydes, as well as a variety of substituted norbornenes. The corresponding tetrahydroquinolines are formed with high complexity in a multicomponent fashion and are obtained in good yield and high diastereoselectivity. In addition, more reactive ethyl glyoxylate derived imines were utilized to achieve faster, room temperature reactions with norbornene. In all cases, attack of the N-arylimine dienes occurred exclusively from the exo-face of the norbornene ring, but the relative stereochemistry of the substituent alpha to the tetrahydroquinoline nitrogen, as well as the regioselectivity of reaction, was shown to depend upon subtle substituent effects on the aniline precursors. In most cases, a preference for the formation of exo-exo diastereomeric adducts was observed, but for reactions of ortho- or meta-substituted anilines, the formation of exo-endo adducts was also observed. These observations may be rationalized by two competing mechanistic models, involving either a concerted asynchronous [4 + 2]-like mechanism or a stepwise mechanism.

Reaction prospecting studies resulted in the discovery of a Sc(OTf) 3 promoted novel AA′B 2:1 coupling of imidazolone or benzofuran substituted enals with morpholine. A related Sc(OTf) 3 /morpholine promoted reaction was demonstrated for the coupling of a benzofuran substituted enal with dihydrofuran. The formation of these adducts is consistent with formal inverse electron demand Diels–Alder cycloadditions, most likely in a stepwise manner via a domino Michael–Mannich annulation process, involving iminium ion activation of the diene. A purely amine promoted formal inverse electron demand Diels–Alder cycloaddition approach was also demonstrated in the 2:1 coupling of 2,4-hexadienal with methanol. These reactions demonstrate the concepts of dual metal/amine catalysis and amine promoted formal inverse electron demand Diels–Alder cycloadditions. They differ from known examples of organocatalyzed Diels–Alder reactions, in which iminium ion activation of the dienophiles or enamine activation of the dienes occur.

We describe the morphological changes associated with starvation in larval largemouth bass Micropterus salmoides and develop bivariate and multivariate morphological indices of nutritional status. We obtained hatchery-reared largemouth bass, raised them until completion of fin development, and divided them into two randomized experimental groups of fed and unfed fishes. Fed fishes were provided with newly hatched brine shrimp twice daily. We quantified morphological changes in body shape using 23 morphometric characters. After only 3 d of food deprivation, we were able to detect statistically significant differences in morphology between the fed and unfed fish using multivariate analysis. The magnitude of the mean difference increased over time. An unexpected result suggested that a simple, bivariate ratio of standard length to body depth at the anus was almost as efficient and robust at classifying fed and unfed largemouth bass from an independent data set as a multivariate index based on all 23...

Both nature and position of the substituents have a strong effect on the regio- and chemoselective outcome of the reaction.

A 6-year-old castrated dromedary camel (Camelus dromedarius) presented with a non-healing, severely pruritic, ulcerative fibrotic plaque located at the medial canthus. Histological examination of surgical biopsies identified degenerating nematode larvae within eosinophilic granulomas. Treatment involved repeated debridement of the lesion, injectable ivermectin and anti-inflammatory therapies, and injectable and topical antibiotics. A specially constructed mask with goggles to prevent the camel from continuing to self-traumatize the eye and lesion was also placed. Full recovery occurred approximately 1 month after diagnosis. Because of the location of the lesion, time of year, the gross and microscopic characteristics of the lesion, the presence of a likely nematode larva and the response to treatment, a diagnosis of cutaneous habronemiasis was made.

Generally, the hetero-Diels−Alder reaction (Povarov reaction) of N-arylimine dienes are limited to reaction with activated, electron-rich alkenes. However, introduction of ring strain in the dienophile, as with moderately strained bicyclo[2.2.1]heptenes (norbornene), enables three-component Povarov reaction with in situ formed N-arylimines under Lewis acid catalyzed conditions (BF3·OEt2). The reactions proceed efficiently with a diverse set of commercially available anilines and benzaldehydes, as well as a variety of substituted norbornenes. The corresponding tetrahydroquinolines are formed with high complexity in a multicomponent fashion and are obtained in good yield and high diastereoselectivity. In addition, more reactive ethyl glyoxylate derived imines were utilized to achieve faster, room temperature reactions with norbornene. In all cases, attack of the N-arylimine dienes occurred exclusively from the exo-face of the norbornene ring, but the relative stereochemistry of the substituent α to the tetr...

Abstract Overall, the Operational Readiness activities have been very positive on Brutus. A strong core group of personnel were put in place that did a good job. However, a number of changes were made in the organizational model and the staff ramp-up for Operations personnel that might have gone too far, especially considering some of the technical changes that were also introduced in the Brutus design. In addition, the work environment changed considerably from 1998 to 2001 and some of the assumptions concerning workloads and skilled staff availability did not manifest themselves exactly as assumed. This paper will discuss the model implemented on Brutus and provide a hindsight critique of the model. Introduction Starting up Major Projects will continue to be a vital part of the E&P business. As the number of projects increase, the demand for experienced Operations personnel to work on the front-end activities will also increase. Unfortunately, it is always a challenge to pull these people in from the active field locations to work on assets that are not currently producing revenue. It is important to get the right balance between streamlining these activities versus going too far and having a new project start-up that is not operational or experiences significant issues during its first year of operation. Brutus is the fifth TLP platform for Shell in the Gulf of Mexico. For each of the previous four, Shell Production Operations personnel got engaged early on in "Operational Readiness" activities aimed at assuring that the new facility is operationally ready to produce and the personnel are ready as well. However, the degree to which Operations was involved on the past projects varied considerably. For the Brutus project, attempts were made to learn from the previous projects and standardize the processes so that they can be replicated for future projects. In addition, we tried to take advantage of the fact that we had put four TLPâ??s into service and we had a great wealth of operational readiness information that did not have to be reinvented for Brutus, as well as a strong base of experienced operations personnel. This lead to changes in the Operations organizational design and the model for engagement prior to first production. Major Projects Operations Team (MPOT) Early Operations support for Brutus began with a single individual working with the Project Execution group early in the System Selection phase of the project. He was a resource from a central group called the Major Projects Operations Team (MPOT) within the Production Department. MPOTâ??s role is to provide Operational support to all new development projects in order to ensure that the projects are fully operational at first production. The amount of support varies from one person to a fully staffed organization depending on both the type of project (e.g. Hub facility or subsea tieback) and the phase of the project (eg. System Selection, Project Execution, etc.). Regardless of the type of project, MPOT defines its work as assuring "Operational Readiness".

Predicting values at data points in a specified region when only a few values are known is a perennial problem and many approaches have been developed in response. Interpolation schemes provide some success and are the most widely used among the approaches. However, none of those schemes incorporates historical aspects in their formulae. This study presents an approach to interpolation, which utilizes the historical relationships existing between the data points in a region of interest. By combining the historical relationships with the interpolation equations, an algorithm for making predictions over an entire domain area, where data is known only for some random parts of that area, is presented. A performance analysis of the algorithm indicates that even when provided with less than ten percent of the domain’s data, the algorithm outperforms the other popular interpolation algorithms when more than fifty percent of the domain’s data is provided to them.

Introduction Shell Offshore Inc.'s (SOI) Auger tension leg platform was installed in 2860 feet of water, 215 miles southwest of New Orleans. Nine producing wells were completed during 1994. These well completions presented many unique challenges which have been documented elsewhere." Paramount among these was the requirement that each well produce at high rates of at least 6000 BOPD in order to make the project economically viable. To yield the desired rates, efficient completions were essential. Although the target completion intervals at Auger were very deep >20,000 ft measured depth), the unconsolidated and uncemented nature of the turbidite sands made sand control necessary. In these deep, geopressured, long >150 ft) interval completions, acid stimulation was used extensively. Because of the critical nature of these wells, industry's best practices and up-to-date technology were applied to ensure effective stimulation. With respect to acid stimulation, this meant application of Paccaloni's concepts for treatment design, coupled with real time monitoring of treating data. In this report, we will show how these processes combined to achieve our productivity objectives. Paccaloni's design concepts were used here to scale treatment volumes, rates, and diversion strategies to anticipated well productivity. The design objective is to pump sufficient acid to remove near wellbore damage from the entire completion interval. Maintaining wellbore treating pressure as high as possible without fracturing maximizes acid injection into damaged zones. It is essential to avoid fracturing to maintain injection control. This can be accomplished by maintaining a high injection rate, increasing acid viscosity, or applying diverters. All three approaches were combined in the Auger designs. Real time acidizing is the process of collecting accurate pressure and rate data, calculating bottomhole treating pressure, calculating injectivity and comparing injectivity during the treatment to expected injectivity to evaluate damage removal and stimulation effectiveness. During completion of nine new wells in 501's Auger project, these methods were used to evaluate and improve stimulation procedures. These methods proved invaluable in exceeding productivity targets for the project. Currently, wells at Auger are producing on average 10,000 barrels of oil per day at drawdowns of a few hundred psi. Real time stimulation evaluation first saw widespread use in massive hydraulic fracturing stimulation treatments where the cost of data acquisition and evaluation was modest compared to job cost, and changes could be made in the treatment while it was being pumped. This technology was slower to be applied to matrix acid stimulation. Because of the need to achieve effective stimulation on every well at Auger, the benefits of rapid evaluation of treatment effectiveness far exceeded the cost of obtaining real-time data. Although data were available in real time, the large workstring volume at Auger precluded on-the-fly adjustments of acid or diverter volumes. Rates were adjusted to maintain target treating pressures, where sufficient horsepower was available. P. 103