Tidal Energy: The benthic effects of an operational tidal stream turbine.

The effect of modified flow on epifaunal boulder reef communities adjacent to the SeaGen, the world's first grid-compliant tidal stream turbine, were assessed. The wake of the SeaGen was modelled and the outputs were used in conjunction with positional and substrate descriptor variables, to relate variation in epifaunal community structure to the modified physical environment. An Artificial Neural Network (ANN) and Generalised Linear Model (GLM) were used to make predictions on the distribution of Ecological Status (ES) of epifaunal communities in relation to the turbulent wake of the SeaGen. ES was assigned using the High Energy Hard Substrate (HEHS) index. ES was largely High throughout the survey area and it was not possible to make predictions on the spatial distribution of ES using an ANN or GLM. Spatial pattern in epifaunal community structure was detected when the study area was partitioned into three treatment areas: area D1; within one rotor diameter (16 m) of the centre of SeaGen, area D2; between one and three rotor diameters, and area D3; outside of three rotor diameters. Area D1 was found to be significantly more variable than D2 and D3 in terms of epifaunal community structure, bare rock distributions and ES.

Experimental and Monte Carlo determination of the TG-43 dosimetric parameters for the model 9011 THINSeed brachytherapy source.

PURPOSE: AAPM TG-43 brachytherapy dosimetry parameters for a new, smaller diameter 1251 brachytherapy source (THINSeed, model 9011) were determined using LiF:Mg,Ti thermoluminescent dosimeter (TLD-100) microcubes and Monte Carlo simulations. METHODS: Two polymethyl methacrylate phantoms were machined to hold TLD-100 microcubes at specific locations for the experimental determination of the radial dose function, dose-rate constant, and anisotropy functions of the new source. The TG-43 parameters were also calculated using Monte Carlo simulations. For comparison, the model 6711 source was also investigated. RESULTS: Experimental results for both models 9011 and 6711 sources showed good agreement with Monte Carlo values, as well as with previously published values. CONCLUSIONS: The TG-43 parameters for the new source model are similar to those of model 6711; however, they represent two separate sources and TG-43 parameters used in treatment planning must be source specific.

Pharmacological management of pain and anxiety during emergency procedures in children.

Painful procedures are frequently required during treatment of children in the emergency department and are very stressful for the children, their parents and healthcare providers. Pharmacological methods to safely provide almost painless local anaesthesia, analgesia and anxiolysis have been increasingly studied in children. With knowledge of these methods, and patience, the emergency care provider can greatly reduce the distress often associated with emergency care of children. Topical local anaesthetics such as LET [lidocaine (lignocaine), epinephrine (adrenaline), tetracaine] or buffered lidocaine injected through the wound with fine needles can almost painlessly anaesthetise lacerations for suturing. Topical creams such as lidocaine/ prilocaine (EMLA) or tetracaine, iontophoresed lidocaine, or buffered lidocaine subcutaneously injected with fine needles can make intravenous catheter placement virtually 'painless'. When anxiety is significant, and mild to moderate analgesia/ anxiolysis/amnesia is needed, nitrous oxide can be administered if the proper delivery devices are available. Alternatively, when intensely painful fracture reduction, burn debridement, or abscess drainage is necessary, well tolerated and effective deep sedation can be achieved with careful use of midazolam and either ketamine or fentanyl.

A randomized clinical trial of continuous-flow nitrous oxide and midazolam for sedation of young children during laceration repair.

STUDY OBJECTIVE: To compare the efficacy and complication profile of oral midazolam therapy and continuous-flow 50% nitrous oxide in alleviating anxiety during laceration repair in children 2 to 6 years old. METHODS: We conducted a prospective, randomized clinical trial using 4 study groups who required laceration repair: (1) children who received standard care alone, which included comforting and topical anesthesia augmented with injected lidocaine if needed; (2) children who received standard care and oral midazolam; (3) children who received standard care and nitrous oxide; and (4) children who received standard care, oral midazolam, and nitrous oxide. Videotapes were blindly scored using the Observational Scale of Behavioral Distress-Revised (OSBD-R) to assess distress during baseline, wound cleaning, lidocaine injecting, suturing, and recovery. Adverse effects were noted during suturing and by parent questionnaires completed 24 hours after suturing and at suture removal. OSBD-R data were analyzed using repeated-measures analysis of variance. Adverse effect data were analyzed using categorical models. RESULTS: Two hundred four subjects were enrolled (midazolam plus nitrous oxide 52, midazolam 51, nitrous oxide 51, standard care 50; mean patient age was 4.1 years; 66% were boys). Mean OSBD-R scores were lower for groups that received nitrous oxide during wound cleaning by 2.2 points (95% confidence interval [CI] 1.1 to 3.2), lidocaine injecting by 2.5 points (95% CI 1.4 to 3.5), and suturing by 2.9 (95% CI 1.8 to 3.9). Adverse effects occurred more frequently, and recovery times were longer for groups that received midazolam. CONCLUSION: For facial suturing in 2- to 6-year-old children, regimens including continuous-flow nitrous oxide were more effective in reducing distress, and had fewer adverse effects and shorter recovery times than midazolam.

Hydrophobic-interaction chromatography.

This unit discusses the important parameters in designing and optimizing a separation by hydrophobic interaction chromatography (HIC), including preparing the sample and choosing a matrix, column, and buffer. Protocols are provided for packing and testing a column; determining binding and elution conditions; eluting the sample; and cleaning, regenerating, and storing HIC columns.

Continuous-flow delivery of nitrous oxide and oxygen: a safe and cost-effective technique for inhalation analgesia and sedation of pediatric patients.

Nitrous oxide (N2O) safely and rapidly alleviates the pain and distress of minor procedures in the emergency department (ED). We have found self-administration in children does not consistently achieve acceptable analgesia and sedation. The equipment generally available for ED use is designed for adults and delivers 50% N2O through a demand valve that requires an inspiratory effort of -3 to -5 cm of water to activate gas flow. This is difficult for young children who are crying, have more shallow respirations than adults, or cannot follow instructions. In collaboration with the Departments of Anesthesiology, Dentistry, and Respiratory Therapy, we constructed a continuous-flow system for delivering N2O and oxygen (O2). The following is a description of the components, assembly, and use of a continuous-flow machine that safely and inexpensively delivers N2O and O2 to children.

The "ouchless emergency department". Getting closer: advances in decreasing distress during painful procedures in the emergency department.

Painful and frightening injuries and illnesses are frequent reasons for children to seek care in an emergency department. Painful therapeutic procedures are often a necessary part of emergency care and are very distressful for the children, their parents, and healthcare providers. Inadequately relieved pain and distress have acute and long-term consequences, yet methods for pain and anxiety reduction during frightening minor and major procedures are often not used because of lack of detailed knowledge of techniques and fear of adverse effects. This article reviews psychologic and pharmacologic means of safe and effective reduction of anxiety and pain during emergency department procedures.

Comparison of fentanyl/midazolam with ketamine/midazolam for pediatric orthopedic emergencies.

OBJECTIVE: Emergency management of pediatric fractures and dislocations requires effective analgesia, yet children's pain is often undertreated. We compared the safety and efficacy of fentanyl- versus ketamine- based protocols. METHODOLOGY: Patients 5 to 15 years of age needing emergency fracture or joint reduction (FR) were randomized to receive intravenous midazolam plus either fentanyl (F/M) or ketamine (K/M). Measures of efficacy were observational distress scores and self- and parental-report. Measures of safety were frequency of abnormalities in and need for support of cardiopulmonary function and other adverse effects. RESULTS: During FR, K/M subjects (n = 130) had lower distress scores and parental ratings of pain and anxiety than did F/M subjects (n = 130). Although both regimens equally facilitated reductions, deep sedation, and procedural amnesia, orthopedists favored K/M. Recovery was 14 minutes longer for K/M. Fewer K/M subjects had hypoxia (6% vs 25%), needed breathing cues (1% vs 12%), or required oxygen (10% vs 20%) than did F/M subjects. Two K/M subjects required assisted ventilation briefly. More K/M subjects vomited. Adverse emergence reactions were rare but equivalent between regimens. CONCLUSIONS: During emergency pediatric orthopedic procedures, K/M is more effective than F/M for pain and anxiety relief. Respiratory complications occurred less frequently with K/M, but respiratory support may be needed with either regimen. Both regimens facilitate reduction, produce amnesia, and rarely cause emergence delirium. Vomiting is more frequent and recovery more prolonged with K/M.

Rapid optimization of an ICE inhibitor synthesis using multiple reaction conditions in a parallel array.

Optimization of a 2-step reaction sequence was accomplished in 3-4 days, with over 200 different reaction conditions evaluated. Combinatorial arrays were performed using the optimized conditions to synthesize 590 new compounds which were tested for inhibition against N-His (D381E) ICE. Thirty-five compounds showed at least a tenfold improvement in activity compared to an initial standard.

Medium format enhancement: design of an immobilized heparin affinity media for industrial bioprocessing.

Affinity chromatography is one of the most powerful and selective separation methods available. Recently, affinity methods are being incorporated into industrial processes with some frequency. One of the reasons for this is that affinity media robust enough for industrial bioprocessing are now available. By robust is meant that the media meet stringent requirements for cleanability, sanitization, physical and chemical stability, regulatory and technical support, batch-to-batch reproducibility and reliability of supply. This paper describes a medium format enhancement program to adapt a widely known group-specific affinity medium, Heparin Sepharose CL6B, to the requirements for industrial bioprocessing. The new medium, Heparin Sepharose 6 Fast Flow was designed for the recovery of antithrombia 3 (AT3) at industrial scale. The medium is based upon a highly cross-linked 6% agarose, which is produced in very large scale and is familiar to regulatory agencies. The ligand, heparin, is attached to the matrix by a reductive amination chemistry. The resulting linkage is stable in 0.1 N NaOH for 150 h, showing no decrease in AT3 binding affinity at that time. Heparin has a broad biological functionality and thus is useful chromatographically for the purification of a number of proteins which have an affinity for heparin. Heparin, as a complex sugar, is also a highly charged polyanion and thus has interesting ion-exchange properties. Because of its broad applicability to a number of purification problems, immobilized heparin is a useful case study in medium format enhancement.

Conscious sedation for pediatric orthopaedic emergencies.

The objective of this study was to assess complications and risk factors among children undergoing conscious sedation (CS) with fentanyl (F) and midazolam (M) for reduction of fractures and dislocations. A 22-month retrospective review was made of an urban pediatric emergency department's records after implementing a CS protocol for the administration of F/M. Data collection was facilitated by standard CS forms, and data were analyzed using descriptive statistics, chi 2 analysis, Fisher's exact test, t test, odds ratio, and logistic regression. A total of 339 children (65% boys), mean age of 8.4 years, were enrolled in the study. The mean time to sedation was 11.3 +/- 6.2 minutes and to discharge was 92 +/- 36.3 minutes. The mean total doses of M and F were 0.17 +/- 0.08 mg/kg and 1.5 +/- 0.8 micrograms/kg, respectively. An alteration in respiratory status occurred in 37 (11.0%) patients: 28 (8.3%) had oxygen saturation < 90%; 16 (4.7%) received oxygen; 12 (3.6%) were given verbal breathing reminders, eight (2.4%) received airway positioning maneuvers, and 2 (0.6%) received naloxone. Four patients (1.2%) vomited. None required assisted ventilation, intubation, or admission resulting from complications of CS. Characteristics associated with the respiratory events included female sex (odds ratio = 2.2) and deep sedation (odds ratio = 2.7). We conclude that complications associated with F/M administered by protocol were few, minor, and easily managed. Patients who are female or who enter a state of deep sedation may be at modestly increased risk for alterations in respiratory status. Careful attention to monitoring vital functions on all patients is necessary to provide safe CS.

Acyl silicates and acyl aluminates as activated intermediates in peptide formation on clays.

Glycine reacts with heating on dried clays and other minerals to give peptides in much better yield than in the absence of mineral. This reaction was proposed to occur by way of an activated intermediate such as an acyl silicate or acyl aluminate (i.e., the anhydride of a carboxylic acid with Si-OH or Al-OH), analogous to acyl phosphates involved in several biochemical reactions including peptide bond synthesis. We confirmed the proposed mechanism by trapping the intermediate, as well as by direct spectroscopic observation of a related intermediate. The reaction of amino acids on periodically dried mineral surfaces represents a widespread, geologically realistic setting for prebiotic peptide formation via in situ activation.

Acute ethylene oxide intoxication.

A case of acute ethylene oxide intoxication is described in which neurological involvement was present. Three recurrent seizures over a period of an hour were observed in a 43-year-old female. The patient continued to complain of malaise and inability to perform minor motor tasks up to one week after discharge. Neurological evaluation conducted three weeks after toxic exposure was completely normal. A two-month follow-up showed the patient to be asymptomatic without recurrence of symptoms.

Cockayne syndrome: an atypical case.

We report a case of Cockayne syndrome with several atypical features. The patient displayed many of the typical features, including cachectic bird-headed dwarfism, photodermatitis, normal pressure hydrocephalus, and extraphyramidal and pyramidal tract signs. However, she also displayed the unusual and previously unreported features of late age at onset, relative stability until age 19, and fertility, with a successful pregnancy. Brain biopsy showed hypomyelination, no active demyelination, and fibrillary gliosis.

Adenosine triphosphatase from soybean callus and root cells.

The ATPase activity of a membrane fraction from soybean (Glycine max L.) root and callus cells, presumed to be enriched in plasma membrane, has been characterized with respect to ion stimulation, pH requirement, and nucleotide specificity. The enzyme from both sources was activated by divalent cations (Mg(2+) > Mn(2+) > Zn(2+) > Ca(2+) > Sr(2+)) and further stimulated by monovalent salts. Preparations from root cells were stimulated by monovalent ions according to the sequence: K(+) > Rb(+) > Choline(+) > Na(+) > Li(+) > NH(4) (+) > Cs(+) > tris(+). Membrane preparations from callus cells showed similar stimulatory patterns except for a slight preference for Na(+) over K(+). No synergism between K(+) and Na(+) was found with preparations from either cell source.The pH optimum for ATP hydrolysis in the presence of 50 mm KCl and 3 mm MgSO(4) was 6.5 for both preparations and slightly higher in the presence of 3 mm MgSO(4) alone. The order of nucleotide preference was found to be: ATP >> ADP > GTP > CTP > UTP. Maximal glucan synthetase activity at high (1 mm), but not at low (1 mum), substrate was found to be coincident with the position of this fraction on the sucrose gradient.