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The Lennox Field is a saturated oilfield with a significant primary gas cap at initial conditions. Located in the East Irish Sea withincBlocks 110/14c and 110/15a, the field was discovered in 1992. First oil was achieved in February 1996. Lennox is a rollover anticline structure. The Triassic Ormskirk Sandstone Formation reservoir comprises good-quality aeolian and fluvial sandstones with typicalcporosities of 11–21%. The gas column reaches a height of c.850 ft and overlays a 143 ft oil column. Oil initially-in-place is estimated to be 202 MMbbl, whilst total gas initially-in-place is 521 bcf. The field has been developed by a wellhead platform tied-back to the neighbouring Douglas Complex. The field development has been split into two phases: the first phase focused on oil production and involved the drilling of 12 horizontal and multilateral production wells and two gas injection wells. Oil production ceased in 2012 with total produced volumes of 103 MMbbl. The second phase comprised the gas cap blowdown, and the optimization of the existing well stock for gas production. Eni UK acquired the operatorship of the field in April 2014 and has focused on maximizing and accelerating gas production from the field.

The Douglas Field is located in Block 110/13b in the East Irish Sea. It was the first oilfield to be discovered and produced in the region, having been found in 1990 and brought on stream in January 1996. The field structure comprises a series of north–south-trending, tilted, extensional fault blocks. The reservoir interval is the Triassic Ormskirk Sandstone Formation comprising good quality aeolian and fluvial sandstones. The field is relatively shallow, with the top reservoir at c.2120 ft true vertical depth subsea. The hydrocarbon is a light oil of 44°API gravity with a maximum column height of c.400 ft. The Douglas Field contains an estimated stock tank oil in place of 248 MMbbl and was developed with 22 wells: 15 producers, six water injectors and a single sour gas and condensate disposal well. Electric submersible pumps are installed in oil producers for artificial lift and water injection was utilized from field start-up for pressure maintenance. A water-alternating-gas pilot was implemented on the field in 2017 as an enhanced oil recovery scheme. The field currently produces at a rate of c.4000 bopd, with approximately 90% water cut. The field has produced 103 MMbbl to date, giving a current oil recovery of c.41%.

The early prescribers of penicillin realised that antibiotics should be used wisely and as an adjunct to traditional surgical provision. They predicted that inappropriate use would increase sensitisation to the drug. National Health Service dentists prescribed almost 10% of antibiotics issued in NHS general practice in 2016 and an audit shows that many of these may have been prescribed inappropriately. One of the causes of antimicrobial resistance is over prescription of the drugs. This paper recalls the recommendations of some early users of penicillin, reports on the current prescription patterns of dentists in England, describes the mechanism of acquisition of anti-microbial resistance and discusses dentists' role in attempting to reduce the problem.

Hydrocarbon exploration in the East Irish Sea Basin began with the identification of surface oil seeps in peat beds in Lancashire, UK. This precipitated the drilling of the first onshore exploration wells. The discovery of the Formby Field in west Lancashire at the end of the 1930s triggered a wave of further drilling. Wells drilled in west Lancashire had limited success, with only minor hydrocarbon shows, whilst the production from the Formby Field was modest. Nonetheless, the invaluable geological information taken from onshore wells and the ratification of the Continental Shelf Act led to a shift in focus to the offshore and a period of significant interest in the East Irish Sea. Two key periods of oil and gas exploration activity stand out in the history of the offshore basin, the first headed by the Gas Council during the 1970s resulted in the discovery of the gas giants of Morecambe Bay, whilst the second fronted by Hamilton Oil during the 1990s heralded the discovery of oil with the Douglas and Lennox fields in Liverpool Bay. Exploration in the basin has waned during the last decade; however, to date, this mature hydrocarbon province has yielded estimated hydrocarbon reserves of over 1.8 BBOE (billion barrels of oil equivalent).

The carbon dioxide concentrating system in C4 photosynthesis allows high net photosynthetic rates (PN) at low internal carbon dioxide concentrations (Ci), permitting higher PN relative to stomatal conductance (gs) than in C3 plants. This relation would be reflected in the ratio of Ci to external ambient (Ca) carbon dioxide concentration, which is often given as 0.3 or 0.4 for C4 plants. For a Ca of 360 µmol mol−1 that would mean a Ci about 110–140 µmol mol−1. Our field observations made near midday on three weedy C4 species, Amaranthus retroflexus, Echinochloa crus-galli, and Setaria faberi, and the C4 crop Sorghum bicolor indicated mean values of Ci of 183–212 µ mol mol−1 at Ca = 360 µmol mol−1. Measurements in two other C4 crop species grown with three levels of N fertilizer indicated that while midday values of Ci at high photon flux were higher at limiting N, even at high nitrogen Ci averaged 212 and 196 µmol mol−1 for Amaranthus hypochondriacus and Zea mays, respectively. In these two crops midday Ci decreased with increasing leaf to air water vapor pressure difference. Averaged over all measurement days, the mean Ci across all C4 species was 198 µmol mol−1, for a Ci/Ca ratio of 0.55. Prior measurements on four herbaceous C3 species using the same instrument indicated an average Ci/Ca ratio of 0.69. Hence midday Ci values in C4 species under field conditions may often be considerably higher and more similar to those of C3 species than expected from measurements made on plants in controlled environments. Reducing gs in C4 crops at low water vapor pressure differences could potentially improve their water use efficiency without decreasing PN.

Abstract Some studies of responses of plants to elevated concentrations of carbon dioxide (EC) added CO2 only in the daytime, while others supplied CO2 continuously. I tested whether these two methods of EC treatments produced differences in the seed yield of soybeans. Tests were conducted for four growing seasons, using open top chambers, with soybeans rooted in the ground in field plots. One third of the chambers were flushed with air at the current ambient [CO2] (AC), one third had [CO2] 350 µmol mol−1 above ambient during the daytime (ECd), while one third had [CO2] 350 µmol mol−1 above ambient for 24 h per day (ECdn). ECdn increased seed yield by an average of 62 % over the four years compared with the AC treatment, while ECd increased seed yield by 34 %. Higher seed yield for ECdn compared with ECd occurred each year. In comparing years, the relative yield disadvantage of ECd decreased with increasing overall seed yield. On days with high water vapor pressure deficits, soybean canopies with ECd had smaller midday extinction coefficients for photosynthetically active radiation than canopies with ECdn, because of a more vertical leaf orientation. Hence the seed yield of soybean at EC varied depending on whether EC was also provided at night, with much greater yield stimulation for ECdn than for ECd in some years.

A limited study has been made of the effect of layer and bond strengths on the longitudinal tensile failure mode of an all beryllium laminate comprising a ductile (~ 5% elongation), high purity substrate and an adhering, brittle (<1%), layer. It is proposed that the overall ductility is related to the extent of delamination at the interface which, in turn, is determined by the ratio (R) of bond strength to layer strength. When R is 0.23 extensive delamination along the gauge length is obtained resulting in maximum ductility, but at R=0.41 little separation occurs and the elongation is reduced almost to the minimum, namely that of the brittle layer. A simple calculation indicates that for the material used in this work, the influence on ductility of this mode of failure in the brittle condition may begin to be reduced when the layer is <1/3 of the total composite thickness, when multipoint delamination may be anticipated.

The antitumor antibiotic drug mitomycin reacts with DNA via ring opening of one of its active sites, the aziridine ring. Since the opening of aziridine rings is facilitated by the addition of a positively charged atom to the nitrogen, the possibility of the addition of a lithium ion to a mitomycin analog is investigated withab initio Hartree-Fock calculations. The lithium-ion affinity of the mitomycin aziridine nitrogen atom is found to be 42 kcal/mol, after correcting for the superposition error.

In this note we present a new characterization for subnormality which is purely $ {C^ \ast }$ $ {\sigma _ \bot }(\pi (S)) \subseteq {\sigma _ \bot }(S)$-representation .

Responses to humidity of net photosynthesis and leaf conductance of single attached leaves were examined in populations of herbs from wet soil sites in Beltsville, Maryland and Davis, California, USA. Plants were grown in controlled environments under three conditions which differed in the magnitude of the day-night temperature difference and in daytime air saturation deficit. No population differences in response were found in Abutilon theophrasti. In Amaranthus hybridus stomatal conductance and net photosynthesis were more reduced by increasing leaf to air water vapor pressure difference (VPD) in the population from Beltsville, but only for the growth condition with a constant 25°C temperature. In Chenopodium album, stomatal conductance was more sensitive to VPD in the population from Davis, but only for the growth condition with 28/22°C day/night temperatures. Population differences in the sensitivity to VPD of leaf conductance were associated with differences in leaf area to root weight ratio. The relative reduction of net photosynthesis as VPD increased was greater than, equal to, or less than the relative decrease in substomatal carbon dioxide partial pressure. The pattern depended on species, and on growth condition. From these results one can not conclude that environmental humidity has been a strong selective force in determining sensitivity to humidity of stomatal conductance.

A new variational characterization of the solution of a matrix Riccati equation is presented. The characterization is given as the maximum Hermitian matrix that makes a certain compound matrix Hermitian positive semidefinite. The shorted operator (Schur complement) applied to the compound matrix produces the Riccati equation.

Diurnal changes in net photosynthesis, dark respiration, specific leaf weight, leaf water potential, stomatal conductance, starch and soluble sugar concentrations, and the activities of malate dehydro- genase and glycollate oxidase were measured in soybeans grown in 23/23,26/20 and 29/17°C thermo- periods, to determine their relationship to thermoperiodic effects on plant growth. Soybean height and main stem leaf number were significantly higher under the constant daylnight (23/23°C) temperature regime. Leaf, stem and root dry weights, and specific leaf weight were all highest where the day/night temperature differential was greatest (29/17°C). Differences in net photosynthesis, dark respiration, starch and soluble sugar concentration, and malate dehydrogenase activity were small between the thermoperiod treatments. However, glycollate oxidase activity was higher under the constant-temperature conditions. Starch concentration, specific leaf weight, and glycollate oxidase activity all increased throughout the photoperiod and subsequently decreased through the dark period. Net photosynthesis declined throughout the photoperiod and both dark respiration and malate dehydrogenase activity peaked at the beginning of the dark period. Each of these diurnal responses was similar under each thermoperiod. Leaf water potential and stomatal conductance did not differ between thermoperiods.

A transport system has been proposed using buses operating over ordinary roads and over special reserved tracks (busways) on which they might be automatically guided. Using cost and performance data resulting from an earlier technical study (not reported here), a hypothetical network of routes and services in the West Midlands conurbation is studied. Estimates of patronage diverted from public and private transport enable the profitability of the system and its costs and benefits to be assessed. It is concluded that the system could be attractive both in commercial and in cost/benefit terms, providing acceptable means could be found for handling the buses around and through the inner central areas of cities. The net environmental changes, which would result from additional fixed plant permitting more efficient use of mobile plant, have not been quantified.