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Erosion–corrosion of pipeline steel API-5L-X65 has in recent years become an important issue due to the high sand production rate and watercut in the maturing assets. The scope of using corrosion inhibitor to mitigate erosion–corrosion arises due to a number of industrial demands. The present study has been conducted to assess the performance of API-5L-X65 and the effect of corrosion inhibitor under high velocity (20 m s −1 ) jet impingement in four types of media containing 1.5 wt% sand particles: synthetic Forties brine, Forties brine with 5 vol% hydrocarbon (ISOPAR M), Forties brine and 100 ppm corrosion inhibitor, and Forties brine containing 5% ISOPAR M and 100 ppm corrosion inhibitor. Under jet impingement, the material loss was determined by gravimetric measurements and it is shown that the presence of corrosion inhibitor or hydrocarbon reduces the total material degradation of the pipeline steel in Forties brine. The most significant reduction in material loss rate for pipeline steel appears to result from the media containing both hydrocarbon and corrosion inhibitor in this study where an extremely strong interaction is observed. In situ electrochemistry combined with surface analysis and CFD simulations of the jet impingement have enabled the degradation mechanisms to be studied for different erosion–corrosion conditions.

Summary The Cannonball field is a 1 Tcf gas/condensate development offshore Trinidad producing at a sustained rate in excess of 800 MMcf/D from three wells. The completion design selected was 7⅝- in. production tubing with an openhole gravel pack. The initial well (CAN01) has produced at 333 MMcf/D. These rates are higher than typically experienced, which has raised concerns about the resultant potential for metal erosion. As a result, a rigorous erosion study was initiated. The objective was to evaluate erosion quantitatively at various rates over the life cycle of the well to design the completion appropriately and select the appropriate materials. The erosion nodes within the completion—changes in flow direction (e.g., a tee such as in the wellhead) and/or flow constric- tions—were identified as the tree, a landing-nipple profile near the surface, and a formation-isolation device (FID) positioned in the gravel-pack assembly. The key parameters were defined as particles of sharp sand, with a diameter of 50 μm, at a concentration of 0.1 lbm/MMcf. Erosion rates were calculated using the erosion model, Sand Production Pipe Saver (SPPS), developed by the Erosion/Corrosion Research Center (E/CRC) at the University of Tulsa, USA. Erosion rates were calculated over the life cycle, starting at initial rates of 280 and 400 MMcf/D. Erosion rates were also calculated with and without a liquid film (a protective layer on the pipe wall that can reduce the erosion rate). Erosion results (without a liquid film) at all nodes exceeded BP's erosion limit; however, the erosion results with a thin liquid film were mostly below the company's erosion limit. Determination of the presence and thickness of the liquid film was critical. A multiphasepipeline simulation calculated that a sufficient liquid film would exist at all critical areas. Erosion of the tree was assessed further by computation-fluid-dynamics (CFD) models, which identified several hot spots; thus, additional cladding of all flow-wetted surfaces and rounding of the outlet corner was required. The Cannonball completion design, including the tree, was determined to be capable of sustained rates up to a maximum of 400 MMcf/D. The three-well development, where initial rates have been as high as 333 MMcf/D, has been on production for several years without any erosion issues.

Nicotine, one of the thousands of chemicals in cigarette smoke has a highly debated effect on cell proliferation and tissue healing. Recent studies documented its pro-angiogenesis effects by stimulating endothelial cell alpha7-non-neronal nicotinic acetyl choline receptors (alpha7 N-nACHR). It is well known that individuals who smoke or have diabetes experience impaired wound healing although for different reasons. This review evaluates several current studies relating to nicotine's ability to mediate cellular activation, migration and angiogenesis in attempts to correlate these data with nicotine's ability to repair wounds in ischaemic tissue. While its beneficial effects are still under investigation, important findings regarding nicotine's acceleration of atherosclerosis, tumor angiogenesis, cell proliferation e and resistance to apoptosis put its systemic use into question. Based on the good and bad sides of nicotine, it is recommended to restrict its utility to local applications.

A transgenic corn event (MON 863) has been recently developed by Monsanto Company for control of corn rootworms, Diabrotica spp. (Coleoptera: Chrysomelidae). This transgenic corn event expresses the cry3Bb1 gene derived from Bacillus thuringiensis (Berliner), which encodes the insecticidal Cry3Bb1 protein for corn rootworm control. A continuous feeding study was conducted in the laboratory to evaluate the dietary effect of MON 863 pollen expressing the Cry3Bb1 protein on the survival, larval development, and reproductive capacity of the nontarget species, Coleomegilla maculata DeGeer (Coleoptera: Coccinellidae). First instar C. maculata (less than 24 h old) and newly emerging adults (less than 72 h old) were fed individually on a diet mixture containing 50% of MON 863 pollen, non-transgenic (control) corn pollen, bee pollen (a component of normal rearing diet), or potassium arsenate-treated control corn pollen. In the larval tests, 96.7%, 90.0%, and 93.3% of C. maculata larvae successfully pupated and then emerged as adults when fed on MON 863 pollen, non-transgenic corn pollen, and bee pollen (normal rearing) diets, respectively. Among the larvae completing their development, there were no significant differences in the developmental time to pupation and adult emergence among the transgenic corn pollen, non-transgenic corn pollen, and bee pollen diet treatments. All larvae fed on arsenate treated corn pollen diet died as larvae. For tests with adults, 83.3%, 80.0%, and 100% of adult C. maculata survived for the 30 days of the test period when reared on diets containing 50% of MON 863 pollen, non-transgenic corn pollen, and bee pollen respectively. While the adult survival rate on MON 863 pollen diet was significantly less than that on the bee pollen diet, there was no significant difference between the MON 863 and non-transgenic corn pollen treatments. During the period of adult testing, an average of 77, 80, and 89 eggs per female were laid by females fed on the MON 863 pollen, control corn pollen, and bee pollen, respectively; no significant differences were detected in the number of eggs laid among these treatments. These results demonstrate that when offered at 50% by weight of the dietary component, transgenic corn (MON 863) pollen expressing Cry3Bb1 protein had no measurable negative effect on the survival and development of C. maculata larvae to pupation and adulthood nor any adverse effect on adult survival and reproductive capacity. Relevance of these findings to ecological impacts of transgenic Bt crops on non-target beneficial insects is discussed.

Soil samples were collected from within and outside six fields where insect-resistant transgenic cotton (Bollgard) encoding the Bacillus thuringiensis Berliner (Bt) subsp. kurstaki cry1Ac gene had been grown and subsequently incorporated into soil by postharvest tillage for 3–6 consecutive years. The level of Cry1Ac protein in these samples (collected 3 mo after the last season’s tillage) was evaluated using both enzyme-linked immunosorbent assays (ELISA) and bioassays with a susceptible insect species, Heliothis virescens (F.), the tobacco budworm. Both methods revealed that no detectable Cry1Ac protein was present in any of the soil samples collected from within or outside the Bollgard fields. Based on the results from reference standards, the limit of detection for the ELISA was 3.68 ng of extractable protein per gram of soil, and that of the bioassay (measured by EC50) was 8 ng of biologically active protein per gram of soil. Together, these findings demonstrate that the amount of Cry1Ac protein accumulated as a result of continuous use of transgenic Bt cotton, and subsequent incorporation of plant residues into the soil by postharvest tillage, is extremely low and does not result in detectable biological activity.

The antsPogonomyrmex catifornicusandPheidole tucsonicadisplay cooperative colony foundation with co-foundresses forming associations without respect to relatedness. Geographic variation in method of colony foundation [cooperative (pleometrosis) versus non-cooperative (haplometrosis)] occurs inP. californicus, Acromyrmex versicolor, Myrmecocystus mimicus and Messor pergandei.Such variation in colony founding behavior strongly suggests that comparative studies of the adaptive value of cooperative colony founding will be extremely rewarding.

1. 1. The incidence and severity of thrombo-embolic lesions following myocardial infarction has been studied in 160 cases of myocardial infarction encountered in a series of 2,000 consecutive autopsies. 2. 2. Of the 160 cases of myocardial infarction 73 (45 per cent) had a total of 111 thrombo-embolic lesions. 3. 3. Peripheral infarcts were a main or contributory cause of death in 43 of 160 cases. 4. 4. The use of anticoagulants is thought to be warranted when proper control is available. ∗

The Cannonball Field is a one Tcf gas condensate development offshore Trinidad producing at a sustained rate in excess of 800 MMcf/D from three wells. The completion design selected was 7⅝ inch production tubing with an open-hole gravel pack. The initial well (CAN01) has produced at 333 MMcf/D. These rates are higher than typically experienced which has raised concerns concerns about the resultant potential for metal erosion. As a result, a rigorous erosion study was initiated. The objective was to quantitatively evaluate erosion at various rates over the life cycle of the well to appropriately design the completion and select the appropriate materials. The erosion nodes within the completion - changes in flow direction (e.g. a tee such as in the wellhead) and/or flow constrictions - were identified as: the tree; a landing nipple profile near the surface; and a formation isolation device (FID) positioned in the gravel pack assembly. The key parameters were defined as particles of sharp sand, with a diameter of 50 microns, at a concentration of 0.1 lbs/MMcf. Erosion rates were calculated using the erosion model - Sand Production Pipe Saver (SPPS) - developed by the Erosion/Corrosion Research Center, University of Tulsa, USA. Erosion rates were calculated over the life cycle starting at initial rates of 280 and 400 MMcf/D. Erosion rates were also calculated with and without a liquid film (a protective layer on the pipe wall that can reduce the erosion rate). Erosion results (without a liquid film) at all nodes exceeded BP's erosion limit; however, the erosion results with a thin liquid film were mostly below the company's erosion limit. Determination of the presence and thickness of the liquid film was critical. A multi-phase pipeline simulation calculated that a sufficient liquid film would exist at all critical areas. Erosion of the tree was further assessed by computation fluid dynamics (CFD) models, which identified several hot spots; thus, additional cladding of all flow-wetted surfaces and rounding of the outlet corner was required. The Cannonball completion design, including the tree, was determined to be capable of sustained rates up to a maximum 400 MMcf/D. The three (3) well development, where initial rates have been as high as 333 MMcf/D, has been on production for several years without any erosion issues.

This field study evaluated the ability of a multi-sorbent sampling tube/thermal desorption technique to identify and to provide quantitative data on volatile organic contaminants in indoor air. Air samples, from 12 Canadian homes, were collected on multilayer sorbent cartridges and analyzed using Adsorption/Thermal Desorption coupled with Gas Chromatography/Mass Spectrometry. The study included the identification and quantitation of 23 target compounds. Analysis of sorbent tubes fortified with these target compounds indicated that recoveries were greater than 70 percent and the precision was usually better than 15 percent. These organic compounds were found to be stable on the sorbent tubes for at least seven days. With some exceptions, the target compounds were usually detected at 1 to 10 micrograms/m3 in indoor air samples; other organics identified qualitatively were saturated hydrocarbons, unsaturated hydrocarbons, cyclic hydrocarbons, substituted aromatics, oxygenates, some halogenates and cyclic species such as camphenes/pinenes and carenes.

The importance attached to the development of aluminum-lithium based alloys may be deduced from the fact that over the past seven years four major international conferences (1-4) have been devoted to these materials: The first was held at Stone Mountain, Georgia, in 1980 (1), and the most recent was in Paris in 1987 (4). This rapid sequence of conferences reflects intense research and devel­ opment activity within the laboratories of the aerospace companies, the aluminum companies, many universities, research institutes, and govern­ ment research establishments. One reason for this activity was the need for more fuel efficient aircraft because of escalating fuel prices during the 1970s: the addition of lithium to aluminum simultaneously reduces the density and increases the elastic modulus of the resultant alloy. A second and continuing impetus for the development of these materials comes from the requirements of military aircraft.

We have reviewed our treatment of premalignant and malignant disease of the vulva in 78 patients seen at Colorado General Hospital since 1955. Premalignant lesions can be managed conservatively. Wide local excision or local 5-FU cream usually arrests premalignant disease without further surgery. Patients with premalignant disease treated by one of these methods need to be followed closely in order to detect recurrence. Microinvasive lesions can be treated by wide local excision in selected cases; in others simple vulvectomy is the treatment of choice. Forty-three patients with invasive vulval carcinoma were treated by radical vulvectomy and removal of lymph nodes. Extension at the operation to include the deep retroperitoneal nodes aided in the cure of but one of the 43 patients. Thirty-four patients (79 per cent) are alive and free of disease three to 18 years after radical vulvectomy. Patients with metastasis to regional lymph nodes had a 40 per cent survival rate. If the patients had Stage I, II, or III disease, the presence or absence of positive lymph nodes did not affect the prognosis in our series. All patients with Stage IV disease had positive nodes and eight of nine died.

M., susceptible d'etre un nouveau Christ? L'A. montre qu'il en possede les germes dans sa personnalite, par la potentialite de son accomplissement spirituel: recherche de la verite, lucidite, absence de pulsions violentes, mesure de la parole, independance a l'egard d'autrui et reflexion.

Pharmacological studies showed 3,5-diphenyl-1,2,4-triazole to have both stimulating and depressing effects on the C. N. S. of unanesthetized rats and mice. In moderate doses it lowered blood pressure and stimulated intestinal muscle in anesthetized cats. Neural muscular transmission was blocked in rats and frogs. An inhibition of serum cholinesterase activity by the drug was demonstrated.

Four isosteric mercurial diuretics were synthesized and studied to ascertain the difference between the amide and ester grouping on diuretic activity. A method of synthesis and evidence for an anhydro zwitterion type of structure are presented.

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Redefine-se neste ensaio a noção de gramática, e demonstra-se que as rogras, ou prlncípics, que constituem as línguas são tão passíveis de investigação científica quanto os que subjazem a outros fenômenos naturais. Algumas das regras constitutivas da língua portuguesa são especificadas, e é demonstrado que o conjunto de tais regras constitui uma teoria desta língua. Aventura-se a hipótese de que a forma das regra: reflete características do cérebro humano.

DNA sequence information underpins genetic research, enabling discoveries of important biological or medical benefit. Sequencing projects have traditionally used long (400-800 base pair) reads, but the existence of reference sequences for the human and many other genomes makes it possible to develop new, fast approaches to re-sequencing, whereby shorter reads are compared to a reference to identify intraspecies genetic variation. Here we report an approach that generates several billion bases of accurate nucleotide sequence per experiment at low cost. Single molecules of DNA are attached to a flat surface, amplified in situ and used as templates for synthetic sequencing with fluorescent reversible terminator deoxyribonucleotides. Images of the surface are analysed to generate high-quality sequence. We demonstrate application of this approach to human genome sequencing on flow-sorted X chromosomes and then scale the approach to determine the genome sequence of a male Yoruba from Ibadan, Nigeria. We build an accurate consensus sequence from >30x average depth of paired 35-base reads. We characterize four million single-nucleotide polymorphisms and four hundred thousand structural variants, many of which were previously unknown. Our approach is effective for accurate, rapid and economical whole-genome re-sequencing and many other biomedical applications.

Selected esters were prepared for the purpose of studying the debenzylation reactions when the alcohol portion of the esters was modified. A method is given to obtain esters of oximino acids. Except for phenolic derivatives, the esters were fairly easily prepared from the alcohol and the acid chloride.

The synthesis of selected mono-amides and mono-esters of this dibasic acid is reported. Various condensing methods were tried in the preparation of the dioxo-lone ring in the methylene citric acid. The anhydride, prepared by using phosphorus pentachloride or phosphorus oxychloride, was reacted with the alcohol or the amine in order to obtain the desired mono-derivative. An evaluation of the activity of these compounds will be reported.