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The waste water flows to a typical wastewater treatment plant (WWTP) is comprised from periodic domestic flows and more stochastic industrial flows. Especially variations in the flow of Chemical Oxygen Demand(COD) at the inlet to the WWTP are problematic due to the biological purification process and bio gas production.Traditionally the inlet is un-controlled. A way to reduce variations is to insert a buffer tank near the industrial areas and control the tank outlet according to a prediction of household COD flow. As a first stepa planning tool for operator control of the buffer tank outlet 24 hours ahead is designed. The WWTP in theDanish town Fredericia is used as a case. At the moment the only on-line measurement is the inlet flow tothe wastewater treatment plant and reliable measurements in the network are difficult to establish. A Model Predictive Control scheme is shown to be able to give considerable reduction in the COD flow variations. To do this two models are introduced; one describing the buffer tank and sewer network from the tank to theWWTP and one describing the daily variations in the household flow. Additionally prediction of the industrialoutlet is included. The control scheme has been tested showing good results in a SWMM simulation environment based on network architecture and measurements in Fredericia. The waste water flows to a typical wastewater treatment plant (WWTP) is comprised from periodic domestic flows and more stochastic industrial flows. Especially variations in the flow of Chemical Oxygen Demand (COD) at the inlet to the WWTP are problematic due to the biological purification process and bio gas production. Traditionally the inlet is un-controlled. A way to reduce variations is to insert a buffer tank near the industrial areas and control the tank outlet according to a prediction of household COD flow. As a first step a planning tool for operator control of the buffer tank outlet 24 hours ahead is designed. The WWTP in the Danish town Fredericia is used as a case. At the moment the only on-line measurement is the inlet flow to the wastewater treatment plant and reliable measurements in the network are difficult to establish. A Model Predictive Control scheme is shown to be able to give considerable reduction in the COD flow variations. To do this two models are introduc ed; one describing the buffer tank and sewer network from the tank to the WWTP and one describing the daily variations in the household flow. Additionally prediction of the industrial outlet is included. The control scheme has been tested showing good results in a SWMM simulation environment (ProtectionAgency, 2016) based on network architecture and measurements in Fredericia.

We present the first ever Single Well Chemical Tracer (SWCT) model that incorporates temperature gradients and pH-driven ethyl acetate hydrolysis rate changes when buffering by either calcite in the oil-bearing formation or by chemical species in the injected brine are accounted for. The model is applied to four generic cases with SWCT test, rock formation and brine composition data based on published values. An analytical model is used to calculate how the brine injection temperature decreases with time and an axially symmetric numerical model is used to simulate the cooling of the oil-bearing formation, chemical reactions and transport of species in the reservoir. The primary oil-water partitioning tracer ethyl acetate hydrolyses into the secondary water tracer ethanol and acetic acid that lowers the pH and changes the hydrolysis rate. The acid driven pH decrease may be significantly reduced by pH buffering mechanisms. We investigate four different buffer models. Model 1 may represent a sandstone with calcite cement. In Model 2, also with calcite cement, the brine has less calcium but more bicarbonate and initially lower pH than Model 1. Model 3 is a clean sandstone without calcite cement and the brine contains no calcium but much bicarbonate. Model 4 has no buffer capacity neither in the brine nor in the target formation. Although we discuss only four models, they are quite different and represent an important subset of the realistic SWCT test parameter space. A temperature gradient develops across the primary tracer bank in all four models and this causes the secondary tracer to be displaced away from the wellbore relative to the primary tracer. We find that most of the ethyl acetate hydrolysis takes place during shut-in. The residual oil saturation (Sor) is estimated from the synthetic tracer production curves using the simple chromatographic separation equation as well as with the mean residence time correction. The two methods underestimate the true Sor value (22%) by 3–5 and 3–11% (saturation points), respectively. These results demonstrate that the ‘handicap’ created by the temperature gradient together with the pH-driven hydrolysis rate changes should be taken into account in Sor estimates. We suggest that SWCT tests may be used to evaluate the effective wettability of the target formation at a modest extra cost. Using water tracers with very low quantification limits as primary tracers should reduce or even eliminate the problems caused by temperature gradients and pH-driven hydrolysis rate changes since they will travel well ahead of the temperature gradient and the small amount of acid generated will produce only an insignificant reduction in pH.

Obesity is a possible risk factor of multiple sclerosis (MS), but the association between obesity and MS disease activity has not been explored. In a cohort of 86 MS patients, 80% of overweight or obese patients (BMI≥25kg/m(2)) had MRI activity compared to 48% of the normal-weight patients (BMI25kg/m(2)) (p=0.001) during interferon-beta treatment. NEDA-status (no evidence of disease activity) was defined as a composite that consisted of absence of any relapses, sustained disability-progression and MRI-activity. Among normal-weight patients 26% obtained NEDA-status compared to only 13% of patients with BMI25 (p=0.05). This may indicate that BMI affects interferon-beta treatment response.

Literature on fluid therapy for surgery is updated in regard to coagulation, blood loss and post-operative complications. Haemorrhage depends on the surgical intervention but also on the chosen fluid therapy with artificial colloids affecting coagulation competence and in turn the blood loss. Furthermore, a stable central blood volume as indicated by plasma pro-atrial natriuretic peptide requires a calculated fluid surplus by approximately 2.5 l. Randomized controlled trials recommend haemorrhage to be treated by administration of a crystalloid; however, if the calculated excess of fluid approaches 2 l, albumin may be added.

To explore the relationships between vitamin A, D and E and inflammation in relapsing remitting multiple sclerosis, we assessed their associations with 11 inflammation markers in 9 serial serum samples from 85 patients, before and during interferon-β1a treatment. A negative association was found between vitamin A and pentraxin 3 independent of interferon-β1a use, whereas positive associations between vitamin D and interleukin-1 receptor antagonist and secreted frizzled-related protein 3 were seen before, and between vitamin E and chemokine (C-X-C motif) ligand 16 during interferon-β1a treatment. These findings suggest associations with diverse inflammatory pathways, which may be differentially influenced by interferon-β1a treatment.

Summary Modern drilling ships and rigs are equipped with advanced computer systems for dynamic positioning, power generation and distribution, and drilling operations. It is well-known that software errors may lead to delays and nonproductive time and may compromise safety. Although the testing and verification regime for structures and machinery systems is well-established, most of the computer systems on today's drilling vessels are put into operation without independent testing and verification. Hardware-in-the-loop (HIL) testing is a test methodology used in several other industries. It facilitates the systematic testing of control-system design philosophy, functionality, performance, and failure-handling capability, in both normal and off-design operating conditions, and is conducted in a virtual test bed in which there is no risk to personnel, vessel, or equipment. Automatic drilling systems that rely on software to function properly often consist of a combination of components delivered by several suppliers. This means that, to maintain safety and to achieve the desired operational performance, control-system software from several suppliers must also run and work together as an integrated system. Marine Cybernetics has finalized the testing of drill-floor control systems for seven rigs, involving nine different vendors. This paper presents experiences from these projects in terms of project execution, test timing, and vendor cooperation and participation. Examples of typical observations are also presented.

Objective: To study whether tobacco use is associated with MRI and clinical disease activity in patients with multiple sclerosis (MS). Methods: Prospective cohort study of 87 patients with relapsing-remitting MS originally included in a randomized placebo-controlled trial of omega-3 fatty acids in MS (the OFAMS Study). Serum levels of cotinine (biomarker of tobacco use) were analyzed at baseline and every 6 months for 2 years. MRI activity was assessed at baseline and monthly for 9 months and after 12 and 24 months. Results: Fifty-three patients (61%) had serum cotinine levels ≥85 nmol/L on ≥60% of the measurements and were considered tobacco users and 34 (39%) had cotinine levels

Objective: To evaluate the outcome after spinal surgery when adding prehabilitation to the early rehabilitation. Design: A randomized clinical study. Setting: Orthopaedic surgery department. Subject: Sixty patients scheduled for surgery followed by inpatient rehabilitation for degenerative lumbar disease. Interventions: The patients were computer randomized to prehabilitation and early rehabilitation (28 patients) or to standard care exclusively (32 patients). The intervention began two months prior to the operation. The prehabilitation included an intensive exercise programme and optimization of the analgesic treatment. Protein drinks were given the day before surgery. The early postoperative rehabilitation included balanced pain therapy with self-administered epidural analgesia, doubled intensified mobilization and protein supplements. Main measures: The outcome measurements were postoperative stay, complications, functionality, pain and satisfaction. Results: At operation the intervention group had improved function, assessed by Roland Morris Questionnaire (P = 0.001). After surgery the intervention group reached the recovery milestones faster than the control group (1—6 days versus 3—13, P =0.001), and left hospital earlier (5 (3—9) versus 7 (5—15) days, P =0.007). There was no difference in postoperative complications, adverse events, low back pain and radiating pain, timed up and go, sit-to-stand or in life quality. Patient satisfaction was significantly higher in the intervention group compared with the control group. Conclusion: The integrated programme of prehabilitation and early rehabilitation improved the outcome and shortened the hospital stay — without more complications, pain or dissatisfaction.

Introduction: Preoperative smoking intervention programmes reduce post‐operative complications in smokers. Little is known about the long‐term effect upon smoking cessation. Aim: To discover long‐term quit rates and the reasons behind successful cessation. Materials and Methods: 101 one of 120 smokers, randomised to smoking intervention or no intervention before hip and knee surgery, completed questionnaires concerning smoking after 1 year. We selected representative men and women for focus group interviews. Results: Significantly more patients from the intervention group abstained from smoking for 1 year post‐operatively [13 in 60 patients (22%) vs 2 in 60 (3%), P < 0.01]. Sex (male), low nicotine dependency, non‐smoking spouse and preoperative smoking intervention were related to smoking cessation. All patients gave the same reasons for smoking cessation: improved health and saving money. Follow‐up for 5 years showed 17% of the controls and 8% in the intervention group (P = 0.42) had died. Conclusion: The intervention group had a significantly higher quit rate 1 year after a preoperative smoking cessation programme. (Less)

To explore if vitamin D modulates interferon-β1a treatment effects in relapsing-remitting multiple sclerosis, we examined relationships between serum vitamin D and magnetic resonance imaging (MRI) activity and ten systemic inflammation markers in 88 patients, before and during treatment. Odds ratios for all MRI parameters were negatively associated with vitamin D levels before therapy, but converged to equally low values irrespective of vitamin D status during treatment. During therapy, similar alterations of MRI activity and inflammation markers were found across patients categorized by mean vitamin D values. This suggests that vitamin D status has no major influence on interferon-β1a treatment effects.

Several hundred hydrothermal vent complexes were formed in the Voring Basin as a consequence of magmatic sill emplacement in the late Palaeocene. The 6607/12-1 exploration well was drilled through a 220-m- thick sequence of Eocene-Miocene diatomites with carbonate nodules above the apex of one of these vent complexes. Analysed calcites and dolomites from this interval have isotopic signatures typical for methane seep carbonates, with low d 13 C signatures of )28 to )54& PDB. The data suggest that the vent complex acted as a fluid migration pathway for about 50·10 6 years after its formation, leading to near-surface microbial activity and seep carbonate formation.

We present measurements of Ar-broadening parameters for the R(0) and R(7) lines in the fundamental band of13CO at eight temperatures from 80 to 297 K. The broadening parameters are determined by simultaneous least-squares fitting of spectra recorded using a frequency stabilized diode laser spectrometer. The comparison of the broadening parameter values for R(7) derived at room temperature and different pressures from different line profiles shows that an empirical line profile, which takes into account narrowing effects (Dicke narrowing and absorber speed dependence) but neglects any correlation between collisions, is able to describe the observed lines with constant values of the narrowing and broadening parameters over a 10-500 Torr pressure range. Starting from a recent ab initio potential energy surface, theoretical thermally averaged close coupling values of the Ar broadening parameter are calculated for the same temperatures. The comparison between experimental and calculated values shows an overall agreement of 1.5%. © 2003 Elsevier Inc. All rights reserved.

Monitoring with pulse oximetry might improve patient outcome by enabling an early diagnosis and, consequently, correction of perioperative events that might otherwise cause postoperative complications or even death. The aim of the study was to clarify the effect of perioperative monitoring with pulse oximetry and to identify the adverse outcomes that might be prevented or improved by its use. Trials were identified by computerized searches of the Cochrane Library, MEDLINE, EMBASE, and by checking the reference lists of trials and review articles. All controlled trials that randomized patients to either pulse oximetry or no pulse oximetry during the perioperative period, including in the operating and recovery room, were included in the study. The search identified six reports. Of these 6 reports, 4 studies with data from 21,773 patients were considered eligible for analysis. Two studies specifically addressed the outcomes in question; both found no effect on the rate of postoperative complications using perioperative pulse oximetry. Hypoxemia was reduced in the pulse oximetry group both in the operating room and in the recovery room. During observation in the recovery room, the incidence of hypoxemia in the pulse oximetry group was 1.5-3 times less. There were postoperative complications in 10% of the patients in the oximetry group and in 9.4% in the control group. The duration of hospital stay was a median of 5 days in both groups, and an equal number of in-hospital deaths was registered in both groups. The studies confirmed that pulse oximetry could detect hypoxemia and related events. However, given the relatively small number of patients studied and the rare events being sought, the studies were not able to show an improvement in various outcomes.

Summary Background Smokers are at higher risk of cardiopulmonary and wound-related postoperative complications than nonsmokers. Our aim was to investigate the effect of preoperative smoking intervention on the frequency of postoperative complications in patients undergoing hip and knee replacement. Methods We did a randomised trial in three hospitals in Denmark. 120 patients were randomly assigned 6–8 weeks before scheduled surgery to either the control (n=60) or smoking intervention (60) group. Smoking intervention was counselling and nicotine replacement therapy, and either smoking cessation or at least 50% smoking reduction. An assessor, who was masked to the intervention, registered the occurrence of cardiopulmonary, renal, neurological, or surgical complications and duration of hospital admittance. The main analysis was by intention to treat. Findings Eight controls and four patients from the intervention group were excluded from the final analysis because their operations were either postponed or cancelled. Thus, 52 and 56 patients, respectively, were analysed for outcome. The overall complication rate was 18% in the smoking intervention group and 52% in controls (p=0·0003). The most significant effects of intervention were seen for wound-related complications (5% vs 31%, p=0·001), cardiovascular complications (0% vs 10%, p=0·08), and secondary surgery (4% vs 15%, p=0·07). The median length of stay was 11 days (range 7–55) in the intervention group and 13 days (8–65) in the control group. Interpretation An effective smoking intervention programme 6–8 weeks before surgery reduces postoperative morbidity, and we recommend, on the basis of our results, this programme be adopted.

Background: Previous reports indicate an association between Epstein-Barr virus (EBV) antibody levels and multiple sclerosis (MS) disease activity, but the results have been conflicting. Objectives: The objective of this paper is to study if EBV antibody levels reflect MRI disease activity in MS and examine the potential for EBV antibody levels as biomarkers for treatment response. Methods: A total of 87 MS patients were followed for two years prior to and during interferon beta (IFNB) treatment, with MRI examinations and serum measurement of IgM and IgG antibodies to viral capsid antigen (VCA), EBV nuclear antigen 1 (EBNA-1) and early antigen (EA). Associations between EBV antibody levels and MRI activity were assessed by a logistic regression model. Results: Higher anti-EBNA-1 IgG levels were associated with increased MRI activity, OR = 2.95 (95% CI 1.07–8.10; p = 0.036) for combined unique activity (CUA; the sum of T1Gd+ lesions and new or enlarging T2 lesions). Although most patients were anti-VCA IgM negative, there was an inverse association, OR = 0.32 (95% CI 0.12–0.84; p = 0.021) with CUA during IFNB treatment. Conclusions: This study supports an association between anti-EBNA-1 IgG levels and MS disease activity. We also found an inverse association with anti-VCA IgM levels during IFNB treatment not previously described, indicating anti-VCA IgM as a possible biomarker for IFNB treatment response.

Background This is an update of a review last published in Issue 9, 2009, of The Cochrane Library. Pulse oximetry is used extensively in the perioperative period and might improve patient outcomes by enabling early diagnosis and, consequently, correction of perioperative events that might cause postoperative complications or even death. Only a few randomized clinical trials of pulse oximetry during anaesthesia and in the recovery room have been performed that describe perioperative hypoxaemic events, postoperative cardiopulmonary complications and cognitive dysfunction. Objectives To study the use of perioperative monitoring with pulse oximetry to clearly identify adverse outcomes that might be prevented or improved by its use.The following hypotheses were tested.1. Use of pulse oximetry is associated with improvement in the detection and treatment of hypoxaemia.2. Early detection and treatment of hypoxaemia reduce morbidity and mortality in the perioperative period.3. Use of pulse oximetry per se reduces morbidity and mortality in the perioperative period.4. Use of pulse oximetry reduces unplanned respiratory admissions to the intensive care unit (ICU), decreases the length of ICU readmission or both. Search methods We searched the Cochrane Central Register of Controlled Trials (CENTRAL) (2013, Issue 5), MEDLINE (1966 to June 2013), EMBASE (1980 to June 2013), CINAHL (1982 to June 2013), ISI Web of Science (1956 to June 2013), LILACS (1982 to June 2013) and databases of ongoing trials; we also checked the reference lists of trials and review articles. The original search was performed in January 2005, and a previous update was performed in May 2009. Selection criteria We included all controlled trials that randomly assigned participants to pulse oximetry or no pulse oximetry during the perioperative period. Data collection and analysis Two review authors independently assessed data in relation to events detectable by pulse oximetry, any serious complications that occurred during anaesthesia or in the postoperative period and intraoperative or postoperative mortality. Main results The last update of the review identified five eligible studies. The updated search found one study that is awaiting assessment but no additional eligible studies. We considered studies with data from a total of 22,992 participants that were eligible for analysis. These studies gave insufficient detail on the methods used for randomization and allocation concealment. It was impossible for study personnel to be blinded to participant allocation in the study, as they needed to be able to respond to oximetry readings. Appropriate steps were taken to minimize detection bias for hypoxaemia and complication outcomes. Results indicated that hypoxaemia was reduced in the pulse oximetry group, both in the operating theatre and in the recovery room. During observation in the recovery room, the incidence of hypoxaemia in the pulse oximetry group was 1.5 to three times less. Postoperative cognitive function was independent of perioperative monitoring with pulse oximetry. A single study in general surgery showed that postoperative complications occurred in 10% of participants in the oximetry group and in 9.4% of those in the control group. No statistically significant differences in cardiovascular, respiratory, neurological or infectious complications were detected in the two groups. The duration of hospital stay was a median of five days in both groups, and equal numbers of in-hospital deaths were reported in the two groups. Continuous pulse oximetry has the potential to increase vigilance and decrease pulmonary complications after cardiothoracic surgery; however, routine continuous monitoring did not reduce transfer to an ICU and did not decrease overall mortality. Authors' conclusions These studies confirmed that pulse oximetry can detect hypoxaemia and related events. However, we found no evidence that pulse oximetry affects the outcome of anaesthesia for patients. The conflicting subjective and objective study results, despite an intense methodical collection of data from a relatively large general surgery population, indicate that the value of perioperative monitoring with pulse oximetry is questionable in relation to improved reliable outcomes, effectiveness and efficiency. Routine continuous pulse oximetry monitoring did not reduce transfer to the ICU and did not decrease mortality, and it is unclear whether any real benefit was derived from the application of this technology for patients recovering from cardiothoracic surgery in a general care area.

This study evaluated whether administration of hydroxyethyl starch (HES) 130/0.4 affects coagulation competence and influences the perioperative blood loss.Artificial colloids substitute blood volume during surgery; with the administration of HES 130/0.4 (Voluven, Fresenius Kabi, Uppsala, Sweden) only a minor effect on coagulation competence is expected.Eighty patients were scanned for enrollment in the study, and 40 patients fulfilled the inclusion criteria. Two patients withdrew their consent to participate in the study, and 5 patients were excluded. Thus, 16 patients were randomized to receive lactated Ringer's solution and 17 to receive HES 130/0.4.Among the patients receiving HES 130/0.4, thrombelastography indicated reduced clot strength (P0.001) and blinded evaluation of the perioperative blood loss was 2.2 (range 0.5 to 5.0) versus 1.4 (range 0.5 to 2.4) L in the patients who received HES 130/0.4 or lactated Ringer, respectively (P0.038). The patients in the lactated Ringer's group, however, received more fluid (P0.0001) than those in the HES 130/0.4 group. There was no significant difference between the 2 groups with regard to frequency of reoperations or the length of hospital stay, but use of HES 130/0.4 was both more expensive and less efficacious than the use of lactated Ringer.Administration of HES 130/0.4 reduced clot strength and perioperative hemorrhage increased by more than 50%, while administration of lactated Ringer's solution provoked an approximately 2.5 times greater positive volume balance at the end of surgery.

The NE Atlantic rift system, which has been under extensional deformation since the Caledonian orogeny, experienced a series of rift episodes in Late Paleozoic to Early Cenozoic times (Fig. 1). Late Paleozoic rifting is poorly constrained, particularly with respect to timing. However, rifted basin geometries, inferred to be of this age, are observed at depth in seismic data from the flanks of the younger rift structures.

The potential leaching and availability of nitrogen in biosolids and biosolid-amended glaciated soil were investigated using mineralization and column studies. Aerobic and anaerobic mineralization studies were conducted to assess nitrogen mineralization potential from biosolid-amended glaciated soils and estimate long- and short-term mineralization rates of products. Semicontinuous column studies were conducted to assess the leachability of nitrogen from biosolid-amended soil under simulated unsaturated soil conditions. This study used a Paxton soil because its characteristics are typical of glaciated soil found in New England. Three types of biosolids, which are representative of biosolids currently available in Connecticut, were evaluated: composted biosolids (compost), cement kiln dust stabilized (CKD) biosolids, and heat-dried biosolids (pellet). Results indicate that the pellet product had the greatest mineralization potential (based on unmixed biosolids) at 5 317 mg N/kg, followed by compost (324 mg N/kg) and CKD biosolids (58 mg N/kg). Nitrogen mineralized for the anaerobic test (mixed with soil) varied from 56 to 90% of the total nitrogen and for the aerobic test varied from 19 to 57%. The CKD biosolids percolate consisted primarily of nitrate and nitrite, whereas the predominant nitrogen species found in compost and pellet biosolids percolate was ammonium. Results suggest that one-time application of biosolids at agronomic or liming rates (whichever is limiting) will cause minimal effects to groundwater.

Objective: Alpha-tocopherol is the main vitamin E compound in humans, and has important antioxidative and immunomodulatory properties. The aim of this study was to study alpha-tocopherol concentrations and their relationship to disease activity in Norwegian multiple sclerosis (MS) patients. Methods: Prospective cohort study in 88 relapsing-remitting MS (RRMS) patients, originally included in a randomised placebo-controlled trial of omega-3 fatty acids (the OFAMS study), before and during treatment with interferon beta. The patients were followed for two years with repeated 12 magnetic resonance imaging (MRI) scans and nine serum measurements of alpha-tocopherol. Results: During interferon beta (IFNB) treatment, each 10 µmol/L increase in alpha-tocopherol reduced the odds (CI 95%) for simultaneous new T2 lesions by 36.8 (0.5–59.8) %, p = 0.048, and for combined unique activity by 35.4 (1.6–57.7) %, p = 0.042, in a hierarchical regression model. These associations were not significant prior to IFNB treatment, and were not noticeably changed by gender, age, body mass index, HLA-DRB1*15, treatment group, compliance, or the concentrations of 25-hydroxyvitamin D, retinol, neutralising antibodies against IFNB, or the omega-3 fatty acids eicosapentaenoic acid and docosahexaenoic acid. The corresponding odds for having new T1 gadolinium enhancing lesions two months later was reduced by 65.4 (16.5–85.7) %, p = 0.019, and for new T2 lesions by 61.0 (12.4–82.6) %, p = 0.023. Conclusion: During treatment with IFNB, increasing serum concentrations of alpha-tocopherol were associated with reduced odds for simultaneous and subsequent MRI disease activity in RRMS patients. © 2013 Løken-Amsrud et al. This is an open-access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.

Summary In the mid-1990s, most statistics are still close to the generally accepted modern risk of one death due to anaesthesia per 10 000 administered anaesthetics. However, anaesthetists are faced with an increasing number of patients who are at high risk and who undergo increasingly extensive and prolonged surgical interventions. With the increasing complexity of anaesthetic care, the increasingly complex equipment and increasing demands on anaesthetists, an increase in morbidity and death rates may be expected. There are therefore strong indications to develop and use appropriate protocols for preoperative assessment, perioperative anaesthetic technique and monitoring, and postoperative care and treatment of complications. Problems with training and supervision continue to appear as factors associated with both near misses and death, and concerns about training and supervision continue to be expressed. The Colleges of Surgeons in England and Denmark have recently emphasized the need for consultants to participate fully in the training and supervision of trainees. For some time now, decision theory ( Dowie and Elstein, 1988 ) has been applied to general clinical decision making and it may be relevant to apply this technique to an analysis of factors involved in accidents. The finding that anaesthetists of consultant grade were principally involved in many of the cases reported in the studies of Gannon (1991) and Pedersen and Johansen (1989) suggests that decision making by senior doctors might appropriately be studied in this way. Further developments of new anaesthetic techniques and perioperative monitoring equipment, together with increased focus on training and supervision, have the potential to improve anaesthetic care and reduce the incidence of fatal complications in anaesthesia.

Supplemental Digital Content is available in the text, Background: A meta-analysis concerning perioperative coagulation competence, hemorrhage, and outcome was conducted including the use of hydroxyethyl starches (HESs), dextran, or albumin versus administration of a crystalloid as control to assess the efficacy and safety of colloids and crystalloids for fluid administration during major elective surgery. Surgery was restricted to cardiovascular and noncardiovascular surgery, and HESs were stratified to HES 130/0.4 and HES 200/0.5. Methods: We searched Cochrane Central Register of Controlled Trials, MEDLINE, ISI Web of Science, EMBASE, conference proceedings, reference lists, and databases of ongoing trials. Results: Thirty one primary clinical randomized controlled trials included 2287 patients undergoing major surgery from January 2000 to August 2015. The perioperative changes in coagulation competence were measured by thromboelastography (TEG) maximum amplitude (MA) in 9 studies administering crystalloids versus HES and in 4 studies administering albumin versus HES. All studies but 1 disclosed increased reduction in TEG-MA following HES administration (P = 0.0001 and 0.0002). The total loss of blood was reported in 17 studies in which crystalloids were compared to HES and 12 studies reported increased blood loss after administration of HES (P

For patients exposed to a massive blood loss during surgery, maintained coagulation competence is important. It is less obvious whether coagulation competence influences bleeding during elective surgery where patients are exposed to infusion of a crystalloid or a colloid. This randomized controlled trial evaluates whether administration of 5% human albumin (HA) or lactated Ringer solution (LR) affects coagulation competence and in turn blood loss during cystectomy due to bladder cancer. Forty patients undergoing radical cystectomy were included to receive either 5% HA (n = 20) or LR (n = 20). Nineteen patients were analyzed in the HA group and 20 patients in the lactated Ringer group. Blinded determination of the blood loss was similar in the 2 groups of patients: 1658 (800-3300) mL with the use of HA and 1472 (700-4330) mL in the lactated Ringer group (P = 0.45). Yet, by thrombelastography (TEG) evaluated coagulation competence, albumin affected clot growth (TEG-angle 69 ± 5 vs 74° ± 3°, P

Background: Vitamin A has immunomodulatory properties and may regulate the transcription of genes involved in remyelination. Objective: To investigate the association between retinol and disease activity in multiple sclerosis (MS). Methods: Cohort study of 88 relapsing–remitting MS patients, originally included in a randomised placebo-controlled trial of omega-3 fatty acids in MS (the OFAMS study), followed prospectively for 24 months with repeated assessments of serum-retinol and magnetic resonance imaging (MRI). All patients were initiated on interferon β-1a after month 6. Results: Each 1 µmol/L increase in serum-retinol reduced the odds (95% confidence interval) for new T1 gadolinium enhanced (Gd+) lesions by 49 (8–70)%, new T2 lesions by 42 (2–66)%, and combined unique activity (CUA) by 46 (3–68)% in simultaneous MRI scans, and 63 (25–82)% for new T1Gd+ lesions, 49 (3–73)% for new T2 lesions and 43 (12–71)% for CUA the subsequent month. Serum-retinol also predicted new T1Gd+ and T2 lesions six months ahead. The associations were not affected by HLA-DRB1*15, or serum levels of 25-hydroxyvitamin D, eicosapentaenoic acid or docosahexaenoic acid. Conclusion: Serum retinol is inversely associated with simultaneous and subsequent MRI outcomes in RRMS.

Objective: Studies based on deseasonalized vitamin D levels suggest that vitamin D may influence the disease activity in multiple sclerosis (MS), and high doses are suggested as add-on treatment to interferon-β (IFN-β). Seasonal fluctuation of vitamin D varies between individuals, thus the relationship to disease activity should preferentially be studied by repeated and simultaneous vitamin D and MRI measurements from each patient. Methods: This was a cohort study comprising 88 patients with relapsing-remitting MS who were followed for 6 months with 7 MRI and 4 25-hydroxyvitamin D measurements before initiation of IFN-β, and for 18 months with 5 MRI and 5 25-hydroxyvitamin D measurements during IFN-β treatment. Results: Prior to IFN-β treatment, each 10 nmol/L increase in 25-hydroxyvitamin D was associated with 12.7% ( p = 0.037) reduced odds for new T1 gadolinium-enhancing lesions, 11.7% ( p = 0.044) for new T2 lesions, and 14.1% ( p = 0.024) for combined unique activity. Patients with the most pronounced fluctuation in 25-hydroxyvitamin D displayed larger proportion of MRI scans with new T1 gadolinium-enhancing lesions (51% vs 23%, p = 0.004), combined unique activity (60% vs 32%, p = 0.003), and a trend for new T2 lesions (49% vs 28%, p = 0.052) at the lowest compared to the highest 25-hydroxyvitamin D level. No association between 25-hydroxyvitamin D and disease activity was detected after initiation of IFN-β. HLA-DRB1*15 status did not affect the results. Conclusion: In untreated patients with MS, increasing levels of 25-hydroxyvitamin D are inversely associated with radiologic disease activity irrespective of their HLA-DRB1*15 status.

The Late Carboniferous-Permian (300–240 Ma) Oslo Graben in southeast Norway is a classical continental magmatic rift. About 8–12 km of mafic magma was produced during a period of 40–60 My. The mantle-derived rock volume is ∼ 3 × 105 km3, with an average melt production rate of ∼ 0.005 km3y−1. Initial subsidence and the onset of magmatism preceded graben formation by 5–10 My. Upper crust extension, inferred from dykes and faults, is ⩽ 10%, whereas the total crust appears to have been thinned by up to 30%. The mantle upwelled with a velocity < 2 mMy−1 and suffered conductive heat loss. Adiabatic melting models, therefore, do not apply. A melting model that takes into account syn-rift conductive cooling, depth-variable stretching and mantle composition, suggests that the lithospheric solidus must have been reduced relative to anhydrous peridotite and that mantle thinning should be greater than crustal stretching. The lithospheric affinity of primitive rocks, the initial subsidence, the absence of a hot spot track and the low magma production rate indicate that Oslo Graben magmatism was not associated with a mantle plume. We conclude that the Oslo Graben was more ‘wet’ than ‘hot’ and that extension and magmatism were caused by passive necking of the lithosphere.

Open fractures provide high-permeability pathways for fluid flow in sedimentary basins. The potential for flow along permeable or open fractures and faults depends on the continuity of flow all the way to the surface except in the case of convective flow. Upward flowing fluid cools and may cause cementation due to the prograde solubility of quartz, but in the case of carbonates such flow may cause dissolution. The rate and duration of these processes depend on the mechanisms for sustaining fluid flow into the fracture, the geometries of fracture and sedimentary beds intersected, permeability, pressure and temperature gradients. Heat loss to the adjacent sediments causes sloping isotherms which can induce non-Rayleigh convection. To analyse these problems we have used a simple model in which a single fracture acts as a pathway for vertically moving fluid and there is no fluid transport across the walls of the fracture except near its inlet and outlet. Four mechanisms for fluid flow into the lower part of the fracture are considered: decompression of pore water; compaction of intersected overpressared sediments; focusing of compaction water derived from sediments beneath the fracture; and finally focusing of pore water moving through an aquifer. Water derived from the basement is not considered here. We find that sustained flow is unlikely to have velocities much higher than 1–100 m/yr, and the flow is laminar. The temperature of the fluid expelled at the top of the fracture increases by less than 1% and the vertical temperature gradient in the fracture remains close to the geothermal gradient. Where hot water is introduced from basement fractures (hydrothermal water) during tectonic deformation, much higher velocities may be sustained in the overlying sediments, but here also this depends on the permeability near the surface. Most of the cooling of water with (ore) mineral precipitation will then occur near the surface. In most cases, pore water decompression and sediment compaction will yield only very limited pore water flux with no significant potential for cementation or heating of the sediments adjacent to the fracture. Focusing of compaction water from sediments beneath the fracture or from an intersected aquifer can yield fluxes high enough to cement an open fracture significantly but the flow must be sustained for a very long time. For velocities of 1–100 m/yr, it takes typically 0.3–30 Myr to cement a fracture by 50%. The highest velocities may be obtained when a fracture extends all the way to the surface or sea floor. When a fracture does not reach the sediment surface, the flow velocity is reduced by the displacement of water in the sediments near the top of the fracture. The flow into the fracture from the sediments may often be rate limiting rather than the flow on the fracture. Sedimentary rocks only a few metres from the fracture will receive a much lower flux than the fracture. The fracture will therefore close due to cementation before significant amounts of silica can be introduced into adjacent sandstones. The isotherm slope in the adjacent sediments will in most cases be less than 10–20°. Non-Rayleigh convection velocities in the sediments adjacent to the fracture are too small to cause any significant diagenetic reactions such as quartz cementation. These quantifications of fluid flow in fractures in sedimentary basins are important in terms of constraining models for diagenesis, heat transport and formation of ore minerals in a compaction-driven system.

When continental rifting takes place above a hot asthenosphere, pressure-release melting of adiabatically upwelling mantle may generate large volumes of basaltic melts which subsequently are emplaced at crustal levels and cool. To correctly estimate the heat flow from tectonic subsidence and crustal thinning, it is necessary to account for the melt volumes. A simple physical model of heat flow that incorporates a crustal growth correction on lithospheric extension estimates, as well as the heat in the emplaced magma, has been developed. The principal result is that heat flow may be substantially increased for several million years after rifting, even for a moderately heated asthenosphere.

BackgroundAlthough pulse oximetry is currently In widespread use, there are few data documenting Improvement in patient outcome as a result of the use of oximetry. The authors describe the study design, patient demographic findings, data validation, pulse oximetry failure rate, and overall postopera

BackgroundThe authors describe the effect of pulse oximetry monitoring on the frequency of unanticipated perl-operative events, changes In patient care, and the rate of postoperative complications in a prospective randomized study.MethodsThe study Included 20,802 surgical patients in Denmark randoml

Preoperative smoking intervention programmes reduce post-operative complications in smokers. Little is known about the long-term effect upon smoking cessation.To discover long-term quit rates and the reasons behind successful cessation.101 one of 120 smokers, randomised to smoking intervention or no intervention before hip and knee surgery, completed questionnaires concerning smoking after 1 year. We selected representative men and women for focus group interviews.Significantly more patients from the intervention group abstained from smoking for 1 year post-operatively [13 in 60 patients (22%) vs 2 in 60 (3%), P0.01]. Sex (male), low nicotine dependency, non-smoking spouse and preoperative smoking intervention were related to smoking cessation. All patients gave the same reasons for smoking cessation: improved health and saving money. Follow-up for 5 years showed 17% of the controls and 8% in the intervention group (P = 0.42) had died.The intervention group had a significantly higher quit rate 1 year after a preoperative smoking cessation programme.

Decompression melting of the upwelling mantle during extension of continental lithosphere provides a viable mechanism for the magmatism observed in many rifted sedimentary basins and passive volcanic margins. A model has been developed in which, in addition to the adiabatic temperature decrease, syntectonic conductive cooling, melt transport and emplacement at crustal levels are accounted for. The heat equation including latent heat is solved numerically and the incremental melt fraction is traced to simulate dynamic melting. The emplaced magma is considered an integral part of the continental crust. We find that relative to an instantaneous rifting model with only adiabatic cooling, there is a more than 10% decrease in the melt thickness even when the duration of rifting is as short as 1 m.y. Whether extension takes place with constant horizontal velocity or strain rate has important implications for the amount of melt produced. Consequently, pressure-release melting does not only depend on the amount of stretching and duration of the rift episode, but also on how extension develops through time.

En kvinne i begynnelsen av 20-arene blehenvist til nevrologisk undersokelse grunnetlangsomt progredierende atrofi av de smahandmusklene og tiltakende svekkelse ivenstre og etter hvert ogsa hoyre hand.Symptomene debuterte i slutten av tenarene.Kvinnen hadde alltid vaert frisk, og det varingen kjente nevrologiske sykdommer islekten. Hun beskrev nedsatt finmotorikk ogvanskeligheter med a skrive fordi hun haddedarlig grep om pennen. Tilstanden var ikkeledsaget av smerter eller sensibilitetsfor-styrrelser. Hun hadde ikke observert tegntil funksjonssvikt i proksimal muskulatur iarmene eller i underekstremitetene.Ved nevrologisk undersokelse ble detbemerket markert atrofi og pareser i de smahandmusklene innervert av n. ulnaris ogn. medianus, spesielt thenar, hypothenar,lumbrikalene og interossene (fig 1, fig 2). Detvar ingen sikker atrofi eller pareser i under-armsmuskulaturen. Hun hadde god kraft forfleksjon og ekstensjon i handleddet, slik atmer proksimalt beliggende medianus- ogulnarisinnervert muskulatur samt radialis-innervert muskulatur ble vurdert som intakt.Det var ingen synlig atrofi eller pareser i over-armens eller skulderbuens muskulatur, ogdet var normal muskelfylde med god symme-trisk kraft i begge underekstremitetene.Tempoet for de finere fingerbevegelservar nedsatt, svarende til paresene, for ovrignormalt. Det ble ikke observert fascikulasjo-ner. Koordineringsprovene var upafallende.Pasienten anga normal sensibilitet for allesansekvaliteter. Refleksene var middelslivlige og symmetriske, plantarrefleksenenedadvendte. Hun hadde ingen smerter inakken, det var fri bevegelighet i cervikal-columna og negativt Lhermittes tegn. Hjerne-nerveundersokelse og pasientens mentalestatus var uten anmerkning.

This chapter shows how to conduct a comprehensive, objective and reproducible search for studies. It is always necessary to strike a balance between comprehensiveness and precision when developing a search strategy. Developing a search strategy is an iterative process in which the terms that are used are modified, based on what has already been retrieved. An electronic search strategy should generally have three sets of terms: terms to search for the health condition of interest; terms to search for the intervention(s) evaluated and terms to search for the types of study design to be included. Searches of electronic databases are generally the easiest and least time-consuming way to identify an initial set of relevant reports. The chapter discusses how and where the reviewers should look for studies that may be eligible for inclusion such as The Cochrane Library, MEDLINE, EMBASE and other relevant databases that identify appropriate MeSH terms.

The Cochrane Collaboration is an international non-profit and independent organisation, dedicated to making up-to-date, accurate information about the effects of health care readily available worldwide. The Collaboration is supported by hundreds of organisations from around the world, including health service providers, research funding agencies, departments of health, international organisations and universities. It is a major focus of activity, and a rich source of information within the evidence-based medicine (EBM) movement. The main goal of Cochrane Anaesthesia Review Group (CARG) is to conduct systematic reviews of randomised controlled trials and other controlled clinical trials of interventions. The CARG maintains a register of more than 25000 randomised controlled trials and clinical controlled trials related to anaesthesia, perioperative medicine, intensive care medicine, pre-hospital medicine, resuscitation and emergency medicine. The necessity of The Cochrane Collaboration and EBM has become widely recognised by health professionals and lay people alike.