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1.
P. Richards I. Duncan C. Phipps G. Pickering J. Grzywacz R. Hoult J. Merritt 《Journal of Petroleum Geology》2006,29(3):199-214
Four basins surround the Falkland Islands, but only the North Falkland Basin has been drilled; six wells were drilled there in 1998. Although all six wells encountered good quality sandstones, none of them targeted the basin margins, on what are now thought to be the optimum migration pathways associated with the basin's thick lacustrine source rocks. Subsequently, a 3D seismic survey acquired in 2004 was designed to identify potential basin-margin -derived sandstones entering the basin along transfer zones. From this survey, a number of basin-margin -attached fans have been identified; these prograded into lacustrine waters of varying depths. These Early Cretaceous alluvial/fan delta/deep-lacustrine fan systems are interpreted to provide excellent potential reservoir facies as they are intimately associated with thick, mature source rocks. They will provide the focus for the next planned phase of exploration in the North Falkland Basin.
A phase of drilling is also planned for the basins to the south of the Islands, where large deltaic and fan systems, slightly younger than those imaged in the North Falkland Basin, are seen on seismic to prograde from the same Palaeozoic hinterland that produced the older, North Falkland Basin fans.
This paper attempts to show how sedimentary models derived from targeted seismic programmes following initial exploration can be utilised to plan and improve new drilling campaigns in a frontier basin. It presents an analysis of sediment dispersal patterns in basins of marine and lacustrine origin linked to a single hinterland area, and highlights the nature of the relationship between relay ramp/transfer zone development and sediment dispersal patterns in the subsurface. 相似文献
A phase of drilling is also planned for the basins to the south of the Islands, where large deltaic and fan systems, slightly younger than those imaged in the North Falkland Basin, are seen on seismic to prograde from the same Palaeozoic hinterland that produced the older, North Falkland Basin fans.
This paper attempts to show how sedimentary models derived from targeted seismic programmes following initial exploration can be utilised to plan and improve new drilling campaigns in a frontier basin. It presents an analysis of sediment dispersal patterns in basins of marine and lacustrine origin linked to a single hinterland area, and highlights the nature of the relationship between relay ramp/transfer zone development and sediment dispersal patterns in the subsurface. 相似文献
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JJ Harris DK Lunt SB Smith WL Mies DS Hale M Koohmaraie JW Savell 《Canadian Metallurgical Quarterly》1997,75(4):986-992
Two groups of Brangus steers produced by nuclear transplantation cloning were used in parallel studies investigating the impact of calf- and yearling-feeding. The first group (n = 8) were fed as calves (CF; n = 4) or yearlings (YF; n = 4) to a constant age end point of 16 mo. The second group (n = 10) were fed as calves (CF; n = 5) or yearlings (YF; n = 5) to a constant live weight end point (530 kg). When slaughtered at the same age, CF and YF steers did not differ (P > .05) in feedlot ADG, but the CF steers were heavier and had higher dressing percentages, numeric yield grades, and quality grades (P < .05). Top loin steaks from the groups of steers did not differ (P > .05) in palatability traits. When fed to a constant live weight, the YF steers gained more rapidly (P < .05) and had lower (P < .05) numeric yield grades than did CF steers. Again CF steers had higher (P < .05) dressing percentages. There was no difference (P > .05) between the treatments in carcass quality grade or meat palatability characteristics. Thus, when finished to a constant weight end point, YF steers gained more rapidly, with no adverse effects on carcass quality grade or palatability traits; however, CF steers consistently produced higher dressing percentages, largely due to greater external fatness. 相似文献
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Antibiotic treatment options for Burkholderia cepacia infection are limited because of high intrinsic resistance. The problem is complicated by development of cross-resistance between antibiotics of different classes. We isolated antibiotic-resistant mutants by stepwise exposure to chloramphenicol (Chlor) and to trimethoprim/sulphamethoxazole (T/S) for four B. cepacia strains: ATCC13945, Per (clinical isolate), Cas and D4 (environmental isolates). Chlor(r) mutants did not produce chloramphenicol acetyl-transferase. Cross-resistance, defined as greater than four-fold increase in MIC by microtitre dilution method, was consistently seen in both types of mutants. For chloramphenicol-resistant (Chlor[r]) and trimethoprim/sulphamethoxazole-resistant (Tr/Sr) mutants of B. cepacia ATCC13945 and Cas, no MIC change was seen for piperacillin, ceftazidime, rifampicin, gentamicin, tobramycin, polymyxin B or azithromycin. B. cepacia-Per and -D4 mutants showed cross-resistance to ceftazidime and to piperacillin. Comparison of outer membrane protein (OMP) profiles of B. cepacia and their mutants by SDS-PAGE revealed Tr/Sr) mutants to be deficient in a major OMP (molecular weight 39-47 kDa). Tr/Sr mutants also expressed additional OMPs not found in wild type strains at 75-77 kDa for B. cepacia-ATCC13945 and -Cas, and 20-21 kDa in B. cepacia-D4 and -Per. No OMP changes occurred in Chlor(r) mutants. Lipopolysaccharide (LPS) profiles of each type of mutant showed new high and low molecular weight LPS bands. Cross-resistance seems to be mediated by alterations in porin and LPS for Tr/Sr mutants, but only by LPS in Chlor(r) mutants. 相似文献
6.
Current cementing techniques of distal plugging, pulsatile water cleaning of the canal, and retrograde filling with PMMA in a low-viscous state prepared using porosity reduction techniques and then pressurized have been shown to give excellent results at 10 or more years after operation. However, physical and aging characteristics of PMMA do not guarantee that those results will hold up in the 20- to 30-year time frame. Fifteen-year experience with bony ingrowth systems indicate the development of a durable interface without PMMA, although the interface does appear more vulnerable to attack by the biologic reaction to HMWPE debris. Bone remodeling appears more favorable around proximally fixed bone ingrowth prostheses than around distally fixed prostheses. Softening of the physical characteristics of the stem tip may reduce the incidence of thigh pain. Patients with high activity potential and a life expectancy of greater than 25 years should be strongly considered for a proximally fixed bone ingrowth or ongrowth prosthesis. 相似文献
7.
Jianxin Wei Mark R Pickering Michael R Frater John F Arnold John A Boman Wenjun Zeng 《IEEE transactions on image processing》2005,14(8):1033-1042
It is well known that tile-boundary artifacts occur in wavelet-based lossy image coding. However, until now, their cause has not been understood well. In this paper, we show that boundary artifacts are an inescapable consequence of the usual methods used to choose tile size and the type of symmetric extension employed in a wavelet-based image decomposition system. This paper presents a novel method for reducing these tile-boundary artifacts. The method employs odd tile sizes (2N + 1 samples) rather than the conventional even tile sizes (2N samples). It is shown that, for the same bit rate, an image compressed using an odd tile length low-pass first (OTLPF) convention has significantly less boundary artifacts than an image compressed using even tile sizes. The OTLPF convention can also be incorporated into the JPEG 2000 image compression algorithm using extensions defined in Part 2 of this standard. 相似文献
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JA McCrohon WA Walters JT Robinson RJ McCredie L Turner MR Adams DJ Handelsman DS Celermajer 《Canadian Metallurgical Quarterly》1997,29(7):1432-1436
OBJECTIVES: We sought to assess whether high dose estrogen treatment is associated with enhanced arterial reactivity in genetic males. BACKGROUND: Although estrogens have been shown to enhance arterial reactivity in women, and are thereby thought to confer cardiovascular benefit, the vascular effects of long-term estrogen therapy in genetic males is unknown. METHODS: We studied the arterial physiology of 30 genetic males--15 male to female transsexuals receiving long-term high dose estrogen therapy and 15 healthy male control subjects matched for age, smoking history and vessel size. Using external vascular ultrasound, brachial artery diameter was measured at rest, after flow increase (causing endothelium-dependent dilation [EDD]) and after nitroglycerin (GTN), an endothelium-independent dilator. Blood pressure, cholesterol and testosterone levels were also measured in each subject. RESULTS: Total testosterone and free testosterone index levels were lower in the transsexuals compared with the control subjects (p < 0.001). In contrast, EDD was significantly higher in the transsexuals than in the control males (mean [+/-SD] 7.1 +/- 3.1% vs. 3.2 +/- 2.8%, p = 0.001), as was the GTN response (21.2 +/- 6.7% vs. 14.6 +/- 3.3%, p = 0.002). Total and high density lipoprotein cholesterol, blood pressure levels and baseline vessel size were similar in the two groups. On multivariate analysis, enhanced EDD was associated independently with estrogen therapy (p = 0.02) and with low total cholesterol (p = 0.04). An enhanced GTN response was also significantly associated with estrogen therapy (p = 0.03). CONCLUSIONS: Long-term treatment with high dose estrogens is associated with enhanced arterial reactivity in genetic males, which may be due to the effects of estrogen excess or androgen deprivation, or both. 相似文献
10.
Studies were conducted from May, 1993 to April, 1995 to determine the changing patterns of infection by the liver fluke, Clonorchis sinensis, among residents and fish hosts in Kyongbuk Province. The infection rate among residents was 7.7% by stool examination. The rate in males (11.3%) was significantly higher than females (4.1%). Positive rate of intradermal test was 27.6% in the same population. The special type of a simple catalytic model was applied for the analysis of intradermal positive reactors by age and sex, and the equation was y = 0.4776 (1 - e-0.0375t) for males and, y = 0.2085 (1 - e-0.0138t) for females. Analysis of stool examination data by two-stage catalytic model revealed y = 0.025 (e-0.00471 - e-0.0235t). The annual Clonorchis infection rate was 4.7 per 1,000 susceptibles and the annual loss rate was 23.5 per 1,000 infected. The frequency distribution by the eggs per gram (EPG) was calculated as well as the cumulative percentages of positives. The regression equations were y = 0.929 + 1.506 log x for males and, y = 0.473 + 1.767 log x for females. Of the 25 fish species, 7 species were infected with Clonorchis metacercariae. Infection rates varied by the species, and ranged from 2.8% in Puntungia herzi to 30.0% in Pseudorasbora parva. Average number of the matacercariae per gram of flesh was 58.1 in P. parva, followed by 10.2 in Gnathopogon atromaculatus, 7.0 in Saurogobio dabryi, and 3.0 in Paracheilognathus rhombea. The present study indicates that clonorchiasis in Kyongbuk Province is less prevalent than that of several decades ago. 相似文献