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1.
Upper Barremian – Lower Aptian inner platform “Urgonian” limestones in the Mont de Vaucluse region, SE France, consist of alternating metre-scale microporous and tight intervals. This paper focuses on the influence of structural deformation on the reservoir properties of the Urgonian limestone succession in a study area near the town of Rustrel. Petrographic, petrophysical and structural data were recovered from five fully-cored boreholes, from the walls of a 100 m long underground tunnel, and from a 50 m long transect at a nearby outcrop. The data allowed reservoir property variations in the Urgonian limestones to be studied from core to reservoir scale. Eleven Reservoir Rock Types (RRTs) were identified based on petrographic features (texture, grain size), reservoir properties (porosity, permeability), and the frequency of structural discontinuities such as fractures, faults and stylolites. Tight and microporous reservoir rock types were distinguished. Tight reservoir rock types were characterised by early cementation of intergranular pore spaces and by the presence of frequent structural discontinuities. By contrast microporous reservoir rock types contained preserved intragranular microporosity and matrix permeability, but had very few structural discontinuities. Observed vertical alternations of microporous and tight rock types are interpreted to have been controlled by the early diagenesis of the Urgonian carbonates. Deformation associated with regional-scale tectonic phases, including Albian – Cenomanian “Durancian” uplift (∼105 to 96 Ma) and Pyrenean compression (∼55 to 25 Ma), resulted in the modification of the initial petrophysical properties of the Urgonian limestones. An early diagenetic imprint conditioned both the intensity of structural deformations and the associated circulations of diagenetic and meteoric fluids. Evolution of the Reservoir Rock Types is therefore linked both to the depositional conditions and to subsequent phases of structural deformation.  相似文献   
2.
OBJECTIVE: The predictive value of electrophysiologic visual testing in Creutzfeldt-Jakob disease (CJD) was investigated, and the retinal pathologic findings in three cases are reported. BACKGROUND: The fatal prognosis of CJD, its transmissibility, and the lack of treatment make early diagnosis essential in averting human-to-human transmission. Electroretinogram and visual evoked potentials have been studied in few cases of CJD. METHODS: A visual electrophysiologic examination was performed in 41 consecutive patients referred with suspected CJD. The disease had been diagnosed in 24 patients (CJD group; 15 were confirmed neuropathologically and 9 by clinicolaboratory methods in accordance with diagnostic criteria). The remaining 17 patients were diagnosed with other neurologic disorders, and served as a control group. RESULTS: Flash electroretinogram revealed a significant decrease in the amplitude of the B1 wave (<60 microV) and the B/A ratio (<2) in the CJD group compared with those in the control group. Flash visual evoked potentials revealed no significant difference in latency, but amplitude was increased (>10 microV) in the CJD group, especially in patients with myoclonus. CONCLUSIONS: The visual electrophysiologic abnormalities provide an interesting noninvasive diagnostic tool in idiopathic CJD. The B1-wave decrease is closely correlated with the outer plexiform layer abnormalities observed on neuropathologic examination.  相似文献   
3.
The seed fatty acid (FA) compositions of Abietoids (Abies, Cedrus, Hesperopeuce, Keteleeria, Pseudolarix, and Tsuga) are reviewed in the present study in conclusion to our survey of Pinaceae seed FA compositions. Many unpublished data are given. Abietoids and Pinoids (Pinus, Larix, Ficea, and Pseudotsuga)—constituting the family Pinaceae—are united by the presence of several Δ5-olefinic acids, taxoleic (5,9–18∶2), pinolenic (5,9,12–18∶3) coniferonic (5,9,12,15–18∶4), keteleeronic (5,11–20∶2), and sciadonic (5,11,14–20∶3) acids, and of 14-methyl hexadecanoic (anteiso-17∶0) acid. These acids seldom occur in angiosperm seeds. The proportions of individual Δ5-olefinic acids, however, differ between Pinoids and Abietoids. In the first group, pinolenic acid is much greater than taxoleic acid, whereas in the second group, pinolenic acid is greater than or equal to taxoleic acid. Moreover, taxoleic acid in Abietoids is much greater than taxoleic acid in Pinoids, an apparent limit between the two subfamilies being about 4.5% of that acid relative to total FA. Tsuga spp. appear to be a major exception, as their seed FA compositions are much like those of species from the Pinoid group. In this respect, Hesperopeuce mertensiana, also known as Tsuga mertensiana, has little in common with Abietoids and fits the general FA pattern of Pinoids well. Tsuga spp. and H. mertensiana, from their seed FA compositions, should perhaps be separated from the Abietoid group and their taxonomic position revised. It is suggested that a “Tsugoid” subfamily be created, with seed FA in compliance with the Pinoid pattern and other botanical and immunological criteria of the Abietoid type. All Pinaceae genera, with the exception of Pinus, are quite homogeneous when considering their overall seed FA compositions, including Δ5-olefinic acids. In all cases but one (Pinus), variations from one species to another inside a given genus are of small amplitude. Pinus spp., on the other hand, have highly variable levels of Δ5-olefinic acids in their FA compositions, particularly when sections (e.g., Cembroides vs. Pinus sections) or subsections (e.g., Flexiles and Cembrae subsections from the section Strobus) are compared, although they show qualitatively the same FA patterns characteristic of Pinoids. Multicomponent analysis of Abietoid seed FA allowed grouping of individual species into genera that coincide with the same genera otherwise characterized by more classical botanical criteria. Our studies exemplify how seed FA compositions, particularly owing to the presence of Δ5-olefinic acids, may be useful in sustaining and adding some precision to existing taxonomy of the major family of gymnosperms, Pinaceae.  相似文献   
4.
OBJECTIVE: The aim of this study was to investigate the effects of age, gender, and target location upon arm reach capacity and posture. BACKGROUND: The older adult population is growing in number. Their specific needs must be better understood to improve the design of work and life spaces. METHOD: Thirty-eight adults, divided into four groups according to their gender and age, participated in the experiment. They were asked to reach 84 targets located in a large space defined according to their anthropometry and reach capacities. Reach capacities and postures were analyzed. RESULTS: On average, older participants showed shorter maximal reach distances (by 4.8% of upper limb length) as compared with younger participants. No gender difference was found for maximum reach distance. Age also had significant effects on reach posture, especially through its interactions with target azimuth. Older participants tended to use their trunk less whenever possible. Reduced neck and trunk/seat axial rotations were observed for the older participants when the target deviated from the sagittal plane. They compensated by a greater rotation of the pelvis with respect to the seat. CONCLUSION: Older people's reach capacities should be taken as references, rather than those of younger people, in order to accommodate a wider range of the population. APPLICATION: These results can be used to improve the arrangement of living spaces and work spaces for older people.  相似文献   
5.
Decision support systems are powerful technologies for complex decision making and problem solving. However, constructing an accurate and interpretable decision support system (DSS) for any domain is a challenge. In this paper, a novel hierarchical co-evolutionary fuzzy system called HiCEFS is presented that can autonomously derive a fuzzy rule-based DSS from exemplar data. Most of the important components in HiCEFS, including irregular shaped membership functions (ISMFs) and fuzzy rules, are generated using a hierarchical co-evolutionary genetic algorithm that simultaneously co-evolves these components in separate genetic populations. Owing to its generic learning capability, the HiCEFS approach can be easily applied to produce DSSs for classification and regression tasks in various domains. As a case study, HiCEFS is employed to construct a DSS for detecting gamma ray signals. Experimental results show that the system is able to successfully discern the gamma rays from background hadrons, and performs superior to other established techniques.  相似文献   
6.
The study and development of transportation systems have been a focus of attention in recent years, with many research efforts directed in particular at modelling traffic behaviour from both macroscopic and microscopic points of views. Although many statistical regression models of road traffic relationships have been formulated, they have proven to be unsuitable due to multiple and ill-defined traffic characteristics. Alternative methods such as neural networks have thus been sought but, despite some promising results, their design remains problematic and implementation is equally difficult. Another salient issue is that the opaqueness of trained networks prevents understanding the underlying models. Hybrid neuro-fuzzy rule-based systems, which combine the complementary capabilities of both neural networks and fuzzy logic, constitute a more promising technique for modelling traffic flow. This paper describes the application of a specific class of neuro-fuzzy system known as the Pseudo Outer-Product Fuzzy-Neural Network using Truth-Value-Restriction method (POPFNN-TVR) for modelling traffic behaviour. This approach has been shown to perform better on such problems than similar architectures. The results obtained highlight the capability of POPFNN-TVR in fuzzy knowledge extraction for modelling inter-lane relationships in a highway traffic stream, as well as in generalizing from sample data, as compared to traditional feed-forward neural networks using back-propagation learning. The model thus obtained automatically can be understood, analysed, and readily applied for transportation planning.  相似文献   
7.
In this paper, we propose a supervisory control approach, based on controlled automata concepts, for the planning for online service-operations control of a new class of passenger land-transport systems ( PLanTSs). A PLanTS belongs to a class of dynamic demand-responsive transportation systems. Rapid advances in information and communication technologies are providing a new infrastructural and communications basis upon which higher levels of automation, flexibility, and integration in the development of such transportation systems can be achieved, but to achieve these necessitates the use of more formal approaches for system planning and design. The supervisory control theory of Ramadge and Wonham offers one such methodology, which presents the design for service-operations control as a formal synthesis of a modular supervisory controller. Importantly, the design solution is guaranteed to satisfy the given behavioral specifications in some optimal fashion, without blocking the completion of certain defined "mandatory" tasks. The supervisory design methodology is presented and illustrated in detail via what, in our opinion, is a simplified but realistic PLanTS model. A structural property of the PLanTS model is used to analytically establish the nonblocking property of the modular supervisory controller designed. All automaton models for the PLanTS and the behavioral specifications considered are provided, together with the automata design of the corresponding modular supervisor.  相似文献   
8.
Redox (reduction–oxidation) reactions control many important biological processes in all organisms, both prokaryotes and eukaryotes. This reaction is usually accomplished by canonical disulphide-based pathways involving a donor enzyme that reduces the oxidised cysteine residues of a target protein, resulting in the cleavage of its disulphide bonds. Focusing on human vitamin K epoxide reductase (hVKORC1) as a target and on four redoxins (protein disulphide isomerase (PDI), endoplasmic reticulum oxidoreductase (ERp18), thioredoxin-related transmembrane protein 1 (Tmx1) and thioredoxin-related transmembrane protein 4 (Tmx4)) as the most probable reducers of VKORC1, a comparative in-silico analysis that concentrates on the similarity and divergence of redoxins in their sequence, secondary and tertiary structure, dynamics, intraprotein interactions and composition of the surface exposed to the target is provided. Similarly, hVKORC1 is analysed in its native state, where two pairs of cysteine residues are covalently linked, forming two disulphide bridges, as a target for Trx-fold proteins. Such analysis is used to derive the putative recognition/binding sites on each isolated protein, and PDI is suggested as the most probable hVKORC1 partner. By probing the alternative orientation of PDI with respect to hVKORC1, the functionally related noncovalent complex formed by hVKORC1 and PDI was found, which is proposed to be a first precursor to probe thiol–disulphide exchange reactions between PDI and hVKORC1.  相似文献   
9.
10.
Reactions between calcium magnesium aluminium silicates (CMAS) and Gd2Zr2O7 or 2ZrO2?Y2O3 (ss) are investigated within a temperature range of 1200–1300 °C and for durations of 1 h–100 h. The evolution of CMAS penetration depth in Gd2Zr2O7 and 2ZrO2?Y2O3 (ss) pellets varies considerably depending on the interaction time. A quantitative analysis of the nature and composition of phases observed in stationary conditions (powder/powder interaction) is performed by SEM-FEG coupled with WDS analyses using micro-agglomerated nanoparticles of Gd2Zr2O7 and 2ZrO2?Y2O3. Faster kinetics of the gadolinium-based system are illustrated through an analysis of the morphology of the reaction area and of the resulting CMAS tightness of reaction products. The compositions and quantities of reaction products observed at equilibrium are very similar for the two systems, but transient states are significantly different.  相似文献   
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