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Trauma accounts for 16-44% of childhood deaths. The number of severely injured children who require pre-hospital advanced airway intervention is thought to be small but there is little published data detailing the epidemiology of these interventions. This study was designed to evaluate the children who received pre-hospital intubation (with or without anaesthesia) in a high volume, physician-led, pre-hospital trauma service and the circumstances surrounding the intervention.We conducted a 12 year retrospective database analysis of paediatric patients attended by a United Kingdom, physician-led, pre-hospital trauma service. All paediatric patients (16 years of age) that were attended and received pre-hospital advanced airway intervention were included. The total number of pre-hospital intubations and the proportion that received a rapid sequence induction (RSI) were established. To illustrate the context of these interventions the ages, injury mechanisms and intervention success rates were recorded.Between 1 January 2000 and 31 October 2011 the service attended 1933 children. There were 315 (16.3%) pre-hospital intubations. Of those intubated, 81% received a rapid sequence induction and 19% were intubated without anaesthesia in the setting of near or actual cardiac arrest. Nearly three quarters of the patients were in the age range of 6-15 years with only 3 patients under the age of 1 year. The most common injury mechanisms that required intubation were Road Traffic Crashes (RTC) and 'falls from height'. These accounted for 79% of patients receiving intubation. Intubation success rate was 99.7% with a single failed intubation during the study period.Pre-hospital paediatric intubation is not infrequent in this high-volume trauma service. The majority of patients received a rapid sequence induction. The commonest injury mechanisms were RTCs and 'falls from height'. Pre-hospital paediatric intubation is associated with a high success rate in this physician-led service.

Mars appears to have experienced little compositional differentiation of primitive lithosphere, and thus much of the surface of Mars is covered by mafic lavas. On Earth, mafic and ultramafic rocks present in ophiolites, oceanic crust and upper mantle that have been obducted onto land, are therefore good analogs for Mars. The characteristic mineralogy, aqueous geochemistry, and microbial communities of cold-water alkaline springs associated with these mafic and ultramafic rocks represent a particularly compelling analog for potential life-bearing systems. Serpentinization, the reaction of water with mafic minerals such as olivine and pyroxene, yields fluids with unusual chemistry (Mg–OH and Ca–OH waters with pH values up to ∼12), as well as heat and hydrogen gas that can sustain subsurface, chemosynthetic ecosystems. The recent observation of seeps from pole-facing crater and canyon walls in the higher Martian latitudes supports the hypothesis that even present conditions might allow for a rock-hosted chemosynthetic biosphere in near-surface regions of the Martian crust. The generation of methane within a zone of active serpentinization, through either abiogenic or biogenic processes, could account for the presence of methane detected in the Martian atmosphere. For all of these reasons, studies of terrestrial alkaline springs associated with mafic and ultramafic rocks are particularly timely. This study focuses on the alkaline Adobe Springs, emanating from mafic and ultramafic rocks of the California Coast Range, where a community of novel bacteria is associated with the precipitation of Mg–Ca carbonate cements. The carbonates may serve as a biosignature that could be used in the search for evidence of life on Mars.

Shock-conditioning is a term used to describe changes in geologic materials resulting from the passage of an explosively driven ground shock. Laboratory and microscopy studies performed on two suites of tuff retrieved prior to and after an underground explosion reveal that: (1) bulk physical properties of shock-conditioned tuff are similar to those of pristine tuff; (2) strength and moduli of tuff shocked to peak radial stresses of 200 MPa and greater are significantly degraded; (3) this degradation is associated with microstructural damage in the form of microcracks and crushed pores; and (4) damage introduced by field (dynamic) loading is greater than that induced by laboratory (quasi-static) loading along the simulated field load path.

This paper reports a case of possible impairment by venlafaxine (Effexor®) associated with a single motor-vehicle accident. Blood concentration of the drug is presented along with some observations of subject behaviour.

The ability to closely control the directions of holes drilled in rock is important in an increasing range of applications. Although the subject has long been important in oil and gas well drilling, attention is focused here on directional control in other rotary drilling applications including mineral exploration, site investigation and horizontal drilling for probing ahead of tunnels and for coal degasification. Hole direction is controlled by drill-string mechanics and rock bit interaction effects. Anisotropy in the mechanical properties of the rock can influence rock-bit interaction and cause bit deviation. A review of laboratory and field evidence and of the theories advanced to explain bit deviation effects in anisotropic rock shows that, although some useful general conclusions can be drawn, the subject is not at all well understood. It is concluded that to develop a better understanding of the subject, the bit deviation forces induced by rock anisotropy should be measured under a variety of rotary drilling conditions. The data so obtained could be applied in modifications of currently available mathematical models of drill-string mechanics which could be used to predict likely bit deviations or to determine the stabilizing or steering forces required for particular drill-string configurations.

PWR steam generators have suffered from a variety of degradation phenomena. This paper identifies the corrosion-related defects and their probable causes and suggests approaches to correct and prevent corrosive activity. In the attempt to solve the degradation problems, research programs have concentrated on modifying materials, stresses, and the chemical environment in both new and operating steam generators. The following corrosion-related defects have been studied: tube wastage, denting, primary side (ID) intergranular stress corrosion cracking (IGSCC), OD-initiated intergranular attack (IGA), pitting, and corrosion fatigue. Plants affected by wastage have greatly reduced their problem by adopting an all volatile treatment (AVT). In the case of denting, a less aggressive chemical environment is recommended. Primary side IGSCC responds to temperature reduction, stress relief, and material improvements, while flushing and boric acid addition minimizes OD-initiated IGA. It has further been shown that pitting can be minimized by sludge lancing and by reducing impurity ingress.

Rock cores of a porphyritic tonalite composition have been loaded in uniaxial stress at strain rates from 10−4 to 103/sec at temperatures of 25°C, −78°C and −191°C. The data presented include axial stress as a function of axial and transverse strain and volume change as a function of axial stress. For the conditions studied, the tonalite was found to exhibit increased stiffness and maximum stress with increasing strain rate and decreasing temperature. Anisotropy was studied by loading samples taken perpendicular and parallel to the bulk core axis. Specimens taken perpendicular to the bulk core axis were found to have increased initial stiffness and decreased maximum stress over specimens taken parallel to the core axis. A petrofabric analysis was made to aid in the interpretation of the experimentally observed behavior. From these data it has been determined that the unconfined behavior of the tonalite is controlled by the deformation of the fine-grained groundmass.

The nature and sequence of deformation in the region of the maximum stress were investigated in specimens deformed in uniaxial stress compression at room temperature and at constant strain rates from 10−4/sec to 103/sec. Microscopic observations show that no visible fracture (> 0·01 mm long ) or other evidence of deformation takes place until > 99% of the average maximum stress at a strain rate of 10−4/sec is attained by the granite. Detailed examination of an incipient shear fracture in a granite specimen suggests that the fracture is formed by the coalescence of links between en echelon inclined grain boundaries and cleavages. Photographs taken during loading in the split-Hopkinson bar device illustrate that macroscopic shear fractures develop before extension fractures in the sequence of events leading to gross failure of the specimens.

A full-scale geothermal wellbore simulator and geothermal seal testing machine were constructed. The major emphasis in the Phase II program, in addition to constructing the above research simulators, includes: simulated tests on full-scale components, i.e., full-scale bits; screening tests on elastomeric seals under geothermal conditions; and initial considerations of research needs for development of sealed high-temperature bits. A detailed discussion of the work is presented. (MHR)

Test results are presented from the seal test machine and bearing-seal package. An overal program summary is given and the major milestones of this phase of the program are shown. (MHR)

Progress in background research needed to develop drill bits for the geothermal environment is reported. Construction of a full-scale geothermal wellbore simulator and geothermal seal testing machine was completed. Simulated tests were conducted on full-scale bits. Screening tests on elastometric seals under geothermal conditions are reported. (JGB)

The test facilities (the geothermal drilling vessel and the geothermal drill-bit seal tester) were completed and de-bugged, and the first tests were run on full-scale research drill bits and drill-bit seals. In addition, more materials information was gathered, and a number of additional seals of high-temperature elastomer materials were obtained for testing. Maurer Engineering, on a subcontract basis, has also been active in the design and procurement of candidate high-temperature drill-bit seals for testing, and has done a literature and patent search on the problem of drill-bit insert retention. Reed Tool Co. has cooperated in the fabrication of drill bits for testing, and has offered consultation on certain seal designs.

The work reported herein is a continuation of the program initiated under DOE contract E(10-1)-1546* entitled "Program to Design and Experimentally Test an Improved Geothermal Bit"; the program is now DOE Contract EG-76-C-1546*. The objective of the program has been to accelerate the commercial availability of a tolling cutter drill bit for geothermal applications. Data and experimental tests needed to develop a bit suited to the harsh thermal, abrasive, and chemical environment of the more problematic geothermal wells, including those drilled with air, have been obtained. Efforts were directed at the improvement of both the sealed (lubricated) and unsealed types of bits. The unsealed bit effort included determination of the rationale for materials selection, the selection of steels for the bit body, cutters, and bearings, the selection of tungsten carbide alloys for the friction bearing, and preliminary investigation of optimized tungsten carbide drilling inserts. Bits build** with the new materials were tested under stimulated wellbore conditions. The sealed bit effort provided for the evaluation of candidate high temperature seals and lubricants, utilizing two specially developed test apparatus which simulate the conditions found in a sealed bit operating in a geothermal wellbore. Phase I of the program was devoted largely tomore » (1) the study of the geothermal environment and the failure mechanisms of existing geothermal drill bits, (2) the design and construction of separate facilities for testing both drill-bit seals and full-scale drill bits under simulated geothermal drilling conditions, and (3) fabrication of the MK-I research drill bits from high-temperature steels, and testing in the geothermal drill-bit test facility. The work accomplished in Phase I is reported in References 1 through 9. In Phase II, the first generation experimental bits were tested in the geothermal drill-bit test facility. Test results indicated that hardness retention at temperature, but not at the expense of fracture toughness, was a primary requirement for geothermal bit bearings. Materials selections for the MK-II bit were made based on these results. Also in Phase II, effort was directed at the screening of elastomers for use as a high-temperature seal for sealed bits. References 10 though 13 report the work performed in Phase II. This report summarizes the work on Phase III, encompassing the period from May 18, 1977, to May 19, 1978. There were two major tasks in Phase III which consisted of material selection, fabrication and testing of MK-III bits and Seal and lubricant evaluation. [DJE -2005]« less

Information, analysis, and conclusions based on the small for-profit venture business model are presented. The necessary tasks are described and progress is reviewed. Water availability and business analysis problems are described. Included in the appendix are materials on land availability, characterization of geothermal resources under Idaho law, and greenhouse analysis and geothermal applications. (MHR)

New bearing and seal designs are outlined, as well as the progress made on developing test facilities for full-size bearing and seal assemblies. (MHR)