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51.
Analysis of the planktonic foraminifers recovered from 1-SCS-2 drill-hole, Florianópolis platform (Pelotas Basin, southern Brazilian Atlantic Margin), allowed recognition of the Catapsydrax dissimilis, Catapsydrax stainforthi, Globorotalia fohsi robusta, Globorotalia mayeri, Globorotalia margaritae evoluta and Globigerinoides trilobus fistulosus Miocene and Pliocene zones and four important hiatuses. Correlation with well 1-SCS-3B and other zonal schemes, as well as recognition of early diagenesis instead of a reworking process, allowed confident age assignment. The Miocene foraminifers constitute a tropical/sub-tropical assemblage, whereas in the Pliocene, the presence of scarce species associated to subantarctic water masses suggests that the Malvinas Current reaches the area but it was not a controlling factor in the paleoenvironmental conditions.  相似文献   
52.
The Late Jurassic succession of Mount Rettenstein (central Northern Calcareous Alps, Austria) is unique in comparison to all other sections known in the Northern Calcareous Alps because it provides the oldest coexistence of radiolarite basin sedimentation with contemporaneous shallow-water carbonate intercalations. An up to 3.5-m-thick debris flow made up of shallow-water carbonate detritus with a radiolaritic matrix is overlain by thin (calcareous) radiolarite, followed by several hundreds of meters of shallow-water carbonates of the Plassen Formation. Benthic foraminifers (Labyrinthia mirabilis Weynschenk and Alveosepta aff. jaccardi) and the radiolarian associations indicate a depositional age of both the debris flow and the basal Plassen Formation around the boundary of Middle/Late Oxfordian resp. in the Late Oxfordian. This is as yet the first unambiguous evidence of Oxfordian shallow-water sedimentation in the Northern Calcareous Alps. This early neritic stage with the settlement of ooid bars and coral-stromatoporoid-reefs, evidenced by the debris flow resediments in siliceous basin sedimentation, is followed by the definite, rapid progradation of the actual Late Oxfordian/Kimmeridgian–Berriasian Plassen Carbonate Platform with its steep slope configuration. Assumably, this evolution was steered by a mixture of both global environmental and regional tectonic constraints.  相似文献   
53.
In biology field, the ontology application relates to a large amount of genetic information and chemical information of molecular structure, which makes knowledge of ontology concepts convey much information. Therefore, in mathematical notation, the dimension of vector which corresponds to the ontology concept is often very large, and thus improves the higher requirements of ontology algorithm. Under this background, we consider the designing of ontology sparse vector algorithm and application in biology. In this paper, using knowledge of marginal likelihood and marginal distribution, the optimized strategy of marginal based ontology sparse vector learning algorithm is presented. Finally, the new algorithm is applied to gene ontology and plant ontology to verify its efficiency.  相似文献   
54.
Summary The accurate reconstruction of the facies architecture in the Jurassic succession of Monte Kumeta, coupled with a detailed biostratigraphy, allow to define dynamics and genetic factors controlling the conversion of a Bahamian-type carbonate platform to a pelagic escarpment. A change from tidalites to oolites i.e. from the restricted, interior lagoon to a more open-marine sandy depositional environment, records the establishment of a basin south of the Monte Kumeta sector in late Hettangian-Sinemurian times. The oolitic limestones are overlain by earliest Carixian bioclastic grainstones and packstones with micritized grains and by wackestones with radiolarians and sponge spicules, organized in thin sand prisms. The decrease of carbonate productivity indicated by these sediments records the dissection of the platform and the subsequent isolation of a submarine topographic high in the Monte Kumeta sector. Though based only on indirect evidence, it is suggested that a tectonically controlled scarp must have existed between the Monte Kumeta “high” and the basin. Progressive northward retreat of this scarp resulted in the conversion of a shallow platform sector into a gradually steepening slope, along which the distribution of sediments was controlled by repeated tectonic and gravity-induced modifications of the topography of the substrate. Vertical and lateral changes and geometrical relationships of the recognized lithofacies suggest that they were deposited on a stepped surface brought about mainly by, repeatedly reactivated basin ward dipping normal faults. This scenario is clearly reflected by the relationship of platform strata and the overlying encrinites of Carixian/Domerian age. The encrinite bodies show again a prismatic geometry, becoming thicker towards the south and filling the first generation of neptunian dykes. The top of the encrinites is marked by a peculiar jagged dissolution surface with dm-scale pinnacles capped by a thick ferromanganese crust. The formation of this peculiar surface could have been controlled by complex changes in water chemistry probably related to the Early Toarcian anoxic event. The crust itself is dissected by faults of decimetres to metres of throw, sometimes organized into small-scale positive flower structures. In the hollows/depressions of this highly articulated substrate pelagic sediments of Bajocian to Oxfordian age were deposited. They display a clearly onlapping relationship to the encrinites and to the carbonate platform beds. Their thickness rarely exceeds 4 to 5 meters and they are present also as neptunian dykes filling a dense network of fissures. During Late Callovian and Oxfordian times synsedimentary tectonics has intensified resulting in an increase of the inclination of the slope. This led to more and more abundant, gravitationally controlled deformations (slumping and sliding) of semi-lithified and unlithified sediments along the Monte Kumeta escarpment.  相似文献   
55.
We investigated the change of the center of pressure (COP) after forward platform translations in healthy subjects. These studies were performed on 26 normal young subjects and 20 healthy elderly subjects, who had a normal neurologic examination. Subjects stood barefoot on a three dimensional force plate on the platform, with feet parallel. The duration of the forward platform translations was 0.15 s, and the displacements were 3.75, 7.5, 10, 15, 20, and 30 mm. Six trials were carried out at random. The COP data were recorded for 35 s during standing, and were analyzed for 5 s after translation. With the platform translation displacements from 3.75 to 15 mm, displacement of the COP showed a tendency to increase in all subjects. Whereas with the stimuli between 20 and 30 mm, the results were more varied. The elderly group showed significantly (p<0.05) larger sway than the young group. These results indicate that the individual ability of posture control may be assessed by means of measuring the sway of the center of gravity after platform translation. Electromyography was carried out simultaneously, it showed that elderly people contrary to young subjects used proximal biceps femoris and distal foot muscles at an early stage of the platform translation (p<0.05), suggesting lack of ankle stability with aging.  相似文献   
56.
This study was conducted to investigate the balance strategy of healthy young adults through a gait cycle using the margin of stability (MoS). Thirty healthy young adults participated in this study. Each performed walking five times at a preferred speed and at a fast speed. The MoS was calculated over a gait cycle by defining the base of support (BoS) changes during a gait cycle. The MoS was divided into medial/lateral and anterior/posterior components (ML MoS and AP MoS). The central values and the values at 12 gait events of the MoS were compared. Positive/negative integration of ML MoS (ML MoSPOS and ML MoSNEG, respectively) and the average ML/AP MoS over a cycle (ML/AP MoSmean) were significantly lower at a fast gait than at a preferred gait. ML/AP MoS were lower at a fast speed than at the preferred speed, except for the ML MoS immediately before left heel strike (pre left HS) and right and left heel strike (HS). ML/AP MoS were significantly lower immediately before heel strike (pre-HS) than in other gait events, regardless of walking speed. It was suggested that pre-HS is the most unstable moment in both ML/AP directions and a crucial moment in control of gait stability. The results presented above might be applicable as basic data regarding dynamic stability of healthy young adults through a gait cycle for comparisons with elderly people and patients with orthopedic disorders or neurological disorders.  相似文献   
57.
The Upper Cretaceous succession in the Madenli area (western Central Taurides, Southern Turkey) consists of platform carbonate rocks deposited in entirely peritidal environments, which are sensitive to sea level changes driven by global eustasy, but also strongly affected by local and regional tectonics. It includes economically important bauxite deposits. Previous works suggest different ages for bauxite formation ranging from the Albian to the Santonian. Benthic foraminiferal biostratigraphy and facies analysis of the Madenli and Doğankuzu outcrop sections allow for a more precise dating of the platform emersion periods. The footwall limestones of the bauxite deposits consist of well-bedded limestones (Unit-1), which contain a benthic foraminiferal assemblage (BFA) including mainly Biconcava bentori and Pastrikella biplana, Chrysalidina gradata (BFA I), assigned to the middle-upper Cenomanian. In the Madenli section, the first bauxite deposit occurs in the upper part of Unit-1 as a layer interbedded with pinkish sparitic and dolomitic beds (subunit-1a) deposited in supratidal environment. Subunit-1a is stratigraphically equivalent to the Doğankuzu and Mortaş bauxite deposits considered as karst-related, unconformity-type deposits. The hanging-wall limestones of the bauxite are represented by the massive limestones (Unit-2) starting locally with either the upper Cenomanian characterized mainly by the presence of Pseudolituonella reicheli or upper Campanian comprising mainly Murciella cuvillieri and Moncharmontia apenninica (BFA II). There is no field evidence of a discontinuity surface at the contact between the lower part of Unit-2, including BFA I, and the upper part of Unit-2, including BFA II. This contact is defined as a paraconformity indicating a stratigraphic gap from the Turonian to the early Campanian. The top of Unit-2 is truncated by another discontinuity surface associated with a minor bauxite deposit. The overlying Unit-3 is characterized by well-bedded, rudist-bearing limestones topped by laminated and dolomitized limestones organized in shallowing upward cycles. It is assigned to the upper Maastrichtian based on the presence of Rhapydionina liburnica (BFA III) and rudist assemblage. A third emersion period of the platform corresponds to the early Maastrichtian.  相似文献   
58.
储一炜  王欣 《生物信息学》2019,26(1):106-110
严子陵钓台是中国隐士文化景观的重要组成部分。通过文献整理,现场调研等研究方法,探索严子陵钓台历史变迁,共分为形成之初、繁荣发展、明清与近代发展3个时期。并且以钓台测绘图为基础,结合古籍文献对盛期钓台进行复原。在此基础上,从山水形胜、文人活动、景面文心3个方面分析了严子陵钓台的景观形成与特征。为严子陵钓台文化景观的保护提供参考,也为同类型文化景观的研究工作提供了一种研究思路。  相似文献   
59.
60.
From its birth, microfluidics has been referenced as a revolutionary technology and the solution to long standing technological and sociological issues, such as detection of dilute compounds and personalized healthcare. Microfluidics has for example been envisioned as: (1) being capable of miniaturizing industrial production plants, thereby increasing their automation and operational safety at low cost; (2) being able to identify rare diseases by running bioanalytics directly on the patient’s skin; (3) allowing health diagnostics in point-of-care sites through cheap lab-on-a-chip devices. However, the current state of microfluidics, although technologically advanced, has so far failed to reach the originally promised widespread use.In this paper, some of the aspects are identified and discussed that have prevented microfluidics from reaching its full potential, especially in the chemical engineering and biotechnology fields, focusing mainly on the specialization on a single target of most microfluidic devices and offering a perspective on the alternate, multi-use, “plug and play” approach. Increasing the flexibility of microfluidic platforms, by increasing their compatibility with different substrates, reactions and operation conditions, and other microfluidic systems is indeed of surmount importance and current academic and industrial approaches to modular microfluidics are presented. Furthermore, two views on the commercialization of plug-and-play microfluidics systems, leading towards improved acceptance and more widespread use, are introduced. A brief review of the main materials and fabrication strategies used in these fields, is also presented. Finally, a step-wise guide towards the development of microfluidic systems is introduced with special focus on the integration of sensors in microfluidics. The proposed guidelines are then applied for the development of two different example platforms, and to three examples taken from literature.With this work, we aim to provide an interesting perspective on the field of microfluidics when applied to chemical engineering and biotechnology studies, as well as to contribute with potential solutions to some of its current challenges.  相似文献   
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