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1.
Cosesaurus aviceps, a small, probable diapsid reptile from the Ladinian (Middle Triassic) of Montral-Alcover (prov. Tarragona, Spain), has been reported as an ancestor of the Neornites. The only known specimen of this taxon is likely an inmature individual. The allometric growth models have been introduced in the character analysis, to infer the features of the adult Cosesaurus. For the present analysis, only the features that can be ascertained without doubt have been retained. The characters have been classified as primitive and derived. Cosesaurus shares all the ten derived characters we have found with Prolacertiformes, especially with Macrocnemus. The sister-group Macrocnemus + Cosesaurus is characterized by the relatively elongated neck in respect both to the skull and trunk length, 7–8 cervical vertebrae with the centra relatively elongated, and a relatively narrow distal femur region. 相似文献
2.
Summary A new dasyclad alga—Acicularia boniae n.sp.—is discribed from Middle Triassic (?Ladinian) of the Piano del Minatore Formation, outcropping in the Cozzo del Pellegrino
area (Calabria, southern Italy). The systematic position of this species, with respect to the genusAcicularia and morphogeneraAciculella andTerquemella, is discussed.
Riassunto Viene descritta una nuova specie di dasicladale—Acicularia boniae—proveniente dal Triassico Medio della formazione del Piano del Minatore affiorante nel massiccio del Cozzo del Pellegrino (Calabria, Italia meridionale). Viene discussa la posizione sistematica rispetto al genereAcicularia ed ai morfogeneriTerquemella edAciculella.相似文献
3.
三叶虫是寒武纪海洋中的常见动物,其受伤愈合现象的化石记录可以反映生态系统内物种之间竞争关系。中国华南寒武纪早期澄江化石生物群因保存软躯体构造化石而成为研究寒武纪大爆发时期古海洋生态群落的绝佳窗口,然而,澄江生物群中三叶虫受伤愈合现象的化石至今未见报道。中间型始莱德利基虫(Eoredlichia intermedia Lu,1940)是澄江生物群的常见物种,也是我国寒武系第二个三叶虫化石带的标准带化石。在2 000余枚中间型始莱德利基虫标本中,发现两枚成体标本的头甲侧边缘、颊刺和胸甲肋节保存了不同程度的残缺。据此推测,Eoredlichia intermedia在生命活动过程中曾受到碎壳型捕食动物的攻击或其他伤害而形成伤口。伤口部位边缘加厚且光滑,显示了明显的愈合痕迹。这些特征表明始莱德利基虫在受到非致死的伤害后,具备自身修复损伤的能力。这是迄今所知最为古老的,也是在澄江生物群中首次发现的三叶虫受伤并且愈合的标本,反映了寒武纪第二世第三期底栖生态系统中碎壳型捕食者和三叶虫猎物之间的军备竞赛生态关系。 相似文献
4.
Summary The late Triassic succession of the Asher-Atlit 1 borehole is over 1000 m thick, and is composed of reefal and associated
facies interbedded with volcanics of Norian age. Only borehole cuttings are available. Microfacies classification and cement
stratigraphy determined by optical and CL microscopy, allowed discrimination of six episodes of reef establishment, progradation,
shallowing, and termination. Organic buildups are constructed of reef-building biota (sponges, possible corals, encrusting
organisms) typical for the late Triassic of the Tethys. Reef-associated facies include fore-slope, central reef, ooid shoal,
lagoonal, and supratidal environments. Cement zoning patterns trace diagenetic signatures which range from early neomorphic
skeletal replacements and original marine cements, via characteristic burial sequences; depositional and diagenetic sequences
are terminated by marginal marine intra- or supratidal conditions, and subaerial exposure with pedogenic overprints. Volcanic
episodes tend to be associated with termination of carbonate sedimentation episodes, while volcanic quiescence and subsidence
permit vertical progradation of reefal and associated facies. The depositional and progradational environment, rapid rate
of sedimentation, periodicity, association with volcanics, and regional considerations, suggest a depositional setting on
the rifted shelf-margin of the nascent Neo-Tethys, with a possible eustatic overprint. 相似文献
5.
Summary East of Cave del Predil (formerly Raibl), a platform-basin transition of the Dolomia Principale (Hauptdolomit) is spectacularly exposed at a seismic scale. Therefore, the eastern margin of the vast domain of the Dolomia Principale, facing the Slovenian Basin, is documented. Despite of strong dolomitization of the massive margin, some sedimentary structures and fossils have been recognized. Corals seem to be very rare and sponges to be absent, whereas serpulids and marine phreatic cements seem to have been the main components of the framework. Interior platform bedded dolomites lap off the massive margin. Clinoforms interfinger with upper Tuvalian basinal deposits (Carnitza Formation). This setting documents the start-up of the Dolomia Principale during late Tuvalian time. Moreover, this margin of the Dolomia Principale is the more ancient so far pointed out. It testifies to the recovery of a rimmed platform after the late Julian-early Tuvalian crisis. 相似文献
6.
Summary A horizon with pot casts (potholes) is described from shallow-marine limestones of thespinosus-zone (‘Discitesschichten’, Upper Muschelkalk) near Weimar/Thuringia. The erosional structures are not developed as sole marks
but occur as isolated structures. They differe distinctly in size and composition from pot casts described from the Muschelkalk
of Southern Germany. Vertical sedimentary zonation and varying sediment infill in the structures suggest continuous erosion
and deposition contemporaneous with the background sedimentation. Deposition may have been caused by oscillatory and unidirectional
flows as well as a long period of micrite deposition. Early diagenetic deformations (e.g. dewatering, brecciation, pressure
solution) have controlled by a higher continuous water flux inside the pot casts and higher intergranular dispersal pressure. 相似文献
7.
Summary This paper is focused on the facies associations of an Early-Middle Norian stratigraphic succession cropping outin the Northern
Calabria (Buonvicino, Cosenza). These carbonate deposits, pertaining to the Verbicaro Unit, represent a dolomitized platform
characterized by a clear dominance of automicrites over skeletal metazoans.
On the basis of the chronostatigraphic data and sedimentary evolution, two stratigraphic units have been distinguished: the
Lower Unit (object of the present paper) and the Upper Unit. The Lower Unit consists of an Early-Middle Norian high-relief
prograding carbonate platform. The Upper Unit is represented by Middle p.p.-Upper Norian basinal deposits.
Three main facies associations, indicative of different depositional settings, have been identified.
The inner platform facies association is characterized by automicrite (cauliflower-columnar subordinate planar stromatolites)
associated with detrital carbonates (intraclastic breccia, bioclastic grainstone and packstone). Apeculiar facies is represented
by megalodontid-bearing beds. Mud-cracked horizons and low-developed teepees occur quite frequently.
The margin facies association is dominated by automicrite (planar to low relief stromatolites associated with thrombolitic
fenestral boundstone) and detrital carbonates with subaerial exposure features.
The slope facies association includes detrital carbonates (breccia/megabreccia) associated with serpulid/sphinctozoan bioconstructions
and automicrite (planar stromatolites/thrombolitic boundstone).
The whole carbonate body is completely dolomitized; nevertheless the morphology and microarchitecture of carbonate components
(cements, grains and automicrite) is still clearly recognizable. The dolomite Mg content ranges from 40 to 48 mole%, sometimes
reaching the stoichiometric value.
Cements, primary and late, represent a minor component of the rock volume; they occur more frequently on the margin and upper
slope setting. Quantitative tacies analyses lead to the following conclusions:
The sedimentary facies and the low-diversity fossil associations seem to indicate a stressed marine environment; the platform
margin probably flanked an intra-platform basin, not an open marine basin. 相似文献
– | ⊙ the entire platform is largely led by automicrite (50% in the inner platform, 70% in the margin, and 30% in the slope), with planar to columnar stromatolitic or thrombolitic fabrics; |
– | ⊙ primary skeletal framework is usually missing, although small bioconstructions of sphinctozoans and, subordinately, serpulids, occur on the slope; |
– | ⊙ automicrite has been affected by early cementation, as witnessed by non-gravitative microfabric, early fracturing and boring. |
8.
摘要 目的:对比桥接组合式内固定系统(OBS)结合Nice结与锁定钢板治疗锁骨中段粉碎性骨折的疗效。方法:回顾性选取2021年6月至2022年1月间在我院接受治疗的锁骨中段粉碎性骨折患者(n=66)的临床资料。根据手术方式的不同将患者分为A组(锁定钢板治疗,32例)和B组(桥接组合式内固定系统结合Nice结,34例),对比两组临床症状恢复情况、并发症发生率、视觉疼痛模拟评分(VAS)、Constant-Murley评分和肩关节活动度。结果:两组骨折愈合时间对比无差异(P>0.05)。B组术中出血量少于A组,手术时间短于A组(P<0.05)。两组术后3个月Constant-Murley评分升高,VAS评分下降(P<0.05),B组术后3个月VAS评分低于A组,Constant-Murley评分高于A组(P<0.05)。两组术后3个月前屈、后伸、内旋、外旋的肩关节活动度增大(P<0.05),且B组术后3个月前屈、后伸、内旋、外旋的肩关节活动度均大于A组(P<0.05)。两组并发症发生率组间比较无统计学差异(P>0.05)。结论:OBS与锁定钢板治疗锁骨中段粉碎性骨折相比,OBS结合Nice结治疗可减少术中出血量,缩短手术时间,促进骨折愈合,扩大肩关节活动度,改善肩关节功能,疗效更好。 相似文献
9.
Andrea Cozzi 《Facies》2002,47(1):151-178
Summary Upper Triassic (Middle-Upper Norian) shallow-water carbonates of the Dolomia Principale and its deep-water counterparts (Forni
Dolomite) have been studied in the Carnian Prealps (northeastern Italy). The Dolomia Principale was a storm-dominated carbonate
platform; in the Mt. Pramaggiore area, along a well-preserved 3.5 km-long platform-to-basin transition, the inner platform
facies of the Dolomia Principale, characterized by m-scale shallowing upward cycles, give way seaward to open marine storm-dominated
shallow subtidal lagoon deposits with frequent hardgrounds and evidence of microbial stabilization of the bottom sediment.
The margin of the Dolomia Principale platform was colonized by meter-scale stromatolites and serpulid-microbial mounds that
thrived due to the local highly stressed environment, characterized by drastic salinity fluctuations and turbid waters, that
excluded the Upper Triassic coral-sponge communities. The Forni Dolomite slope-basin complex was characterized by an upper
slope facies with debris flows, megabreccias, turbidites and serpulid-microbial mounds. The lower slope and basinal facies
show thinning and fining trends. After restoring the original geometry of the slope, the depositional angles of the clinoforms
range between 11 and 36 degrees, reflecting closely the coarse-grained character of the Forni Dolomite slope complex, which
can be interpreted as a slope apron that, as a model, can be extended to steeply inclined carbonate slopes. The onset of synsedimentary
extensional tectonics at the Middle-Late Norian boundary affected the platform-slope depositional system via: 1) localized
inner platform collapses and the formation of an intraplatform anoxic depression at Mt. Valmenone, 2) a switch from platform
lateral progradation during the Middle Norian to vertical aggradation in the Late Norian, reflected in an increase in platform
relief, steeper foreslope angles and coarser-grained slope facies, and 3) controlling the spatial orientation of the margin
of the Dolomia Principale. 相似文献
10.
《Biological reviews of the Cambridge Philosophical Society》2018,93(2):754-784
The Cambrian Explosion is arguably the most extreme example of a biological radiation preserved in the fossil record, and studies of Cambrian Lagerstätten have facilitated the exploration of many facets of this key evolutionary event. As predation was a major ecological driver behind the Explosion – particularly the radiation of biomineralising metazoans – the evidence for shell crushing (durophagy), drilling and puncturing predation in the Cambrian (and possibly the Ediacaran) is considered. Examples of durophagous predation on biomineralised taxa other than trilobites are apparently rare, reflecting predator preference, taphonomic and sampling biases, or simply lack of documentation. The oldest known example of durophagy is shell damage on the problematic taxon Mobergella holsti from the early Cambrian (possibly Terreneuvian) of Sweden. Using functional morphology to identify (or perhaps misidentify) durophagous predators is discussed, with emphasis on the toolkit used by Cambrian arthropods, specifically the radiodontan oral cone and the frontal and gnathobasic appendages of various taxa. Records of drill holes and possible puncture holes in Cambrian shells are mostly on brachiopods, but the lack of prey diversity may represent either a true biological signal or a result of various biases. The oldest drilled Cambrian shells occur in a variety of Terreneuvian‐aged taxa, but specimens of the ubiquitous Ediacaran shelly fossil Cloudina also show putative drilling traces. Knowledge on Cambrian shell drillers is sorely lacking and there is little evidence or consensus concerning the taxonomic groups that made the holes, which often leads to the suggestion of an unknown ‘soft bodied driller’. Useful methodologies for deciphering the identities and capabilities of shell drillers are outlined. Evidence for puncture holes in Cambrian shelly taxa is rare. Such holes are more jagged than drill holes and possibly made by a Cambrian ‘puncher’. The Cambrian arthropod Yohoia may have used its frontal appendages in a jack‐knifing manner, similar to Recent stomatopod crustaceans, to strike and puncture shells rapidly. Finally, Cambrian durophagous and shell‐drilling predation is considered in the context of escalation – an evolutionary process that, amongst other scenarios, involves predators (and other ‘enemies’) as the predominant agents of natural selection. The rapid increase in diversity and abundance of biomineralised shells during the early Cambrian is often attributed to escalation: enemies placed selective pressure on prey, forcing phenotypic responses in prey and, by extension, in predator groups over time. Unfortunately, few case studies illustrate long‐term patterns in shelly fossil morphologies that may reflect the influence of predation throughout the Cambrian. More studies on phenotypic change in hard‐shelled lineages are needed to convincingly illustrate escalation and the responses of prey during the Cambrian. 相似文献
11.
Summary Selected Late Paleozoic and Triassic limestone exposures were studied on northern Palawan Island, Philippines, with regard
to microfacies, stratigraphy and facies interpretation. Although some of the outcrops were already reported in literature,
we present the first detailed microfacies study.
Late Paleozoic carbonates in the El Nido area are represented by widley distributed Permian and locally very restricted Carbonifenous
limestones. Of particular interest is the first report of Carboniferous limestones in the Philippines dated by fossils. Fusulinids
indicate a ‘Middle’ Carboniferous (Moscovian-Kasimovian) age of the Paglugaban Formation only known from Paglugaban Island.
The Permian Minilog Formation consists mostly of fusulinid wackestones and dasycladacean wacke-/packstones. Fusulinid datings
(neoschwagerinids and verbeekinids) provide a Guadalupian (Wordian-Capitanian) age. The depositional setting of the Middle
Permian carbonates corresponds to a distally steepened ramp with biostromes built by alatoconchid bivalves locally associated
with richthofeniid brachiopods.
Late Triassic limestones occur in isolated exposures on and around Busuanga Island (Calamian Islands). The age of the investigated
carbonates is Rhaetian based on the occurrence ofTriasina hantkent
Maizon. Microfacies data indicate the existence of reefs (Malajon Island) and carbonate platforms (Kalampisanan Islands, Busuanga
Island, Coron Island). Reef boundstones are characterized by abundant solenoporacean red algae, coralline sponges and corals.
Platform carbonates yield a broad spectrum of microfacies types, predominantly wacke- and packstones with abundant involutinid
foraminifera and some calcareous algae. These facies types correspond to platform carbonates known from other parts of Southeast
Asia (Eastern Sulawesi and Banda Basin; Malay Peninsula and Malay Basin). The Philippine platform carbonates were deposited
on and around seamounts surrounded by deeper water radiolarian cherts.
The new data on facies and age of the Philippine Permian and Triassic carbonates contradict a close paleogeographical connection
between the North Palawan Block and South China and arise problems for the currently proposed origin of the North Palawan
Block at the paleomargin of South China. We hypothesize that North Palawan was part of the Indochina Block during the Carboniferous
and Permian, separated from the Indochina Block during the Middle Permian and collided with the South China Block in the Late
Cretaceous. 相似文献
12.
Why does a balloon deflate when it is left in a cold car; or why does one have to pump up his or her bike tires in the spring after leaving them in the garage all winter? To answer these questions, students must understand the relationships among temperature, pressure, and volume of a gas. The purpose of the Predict, Share, Observe, and Explain (PSOE) activity is for students to connect the relationships among temperature, pressure, and the amount of gas. Students have many everyday experiences with these relationships, such as pumping up a basketball, but may have never thought of air in terms of pressure and temperature. 相似文献
13.
目的 旨在通过对我院中层管理干部岗位培训的实施与评估,总结培训经验与教训,为进一步提高医院中层管理干部岗位能力提供参考。方法 回顾性分析我院中层管理干部岗位培训的方案制定与实施,并通过分层整群的抽样方法对培训对象进行问卷调查,应用SPSS19.0对数据进行统计分析。结果 不同培训对象层次、性别在培训总体满意度上无显著性差异(P>0.05),培训对象有无相关培训经验在培训总体满意度上有显著性差异(P<0.05);97.84%调查者对授课教师表示满意,79.63%的调查对象对课程设置表示满意,77.48%的调查对象对培训保障措施表示满意,51.67%的调查对象对培训时间与进度表示满意。结论 岗位培训是提高医院中层管理干部岗位能力的核心与关键,应进一步牢固岗位培训意识,将培训工作制度化、流程化,创新培训管理,不断探索完善医院管理干部岗位培训的有效途径和方法。 相似文献
14.
Kathleen Faccia Helen Buie Andrzej Weber Vladimir I. Bazaliiskii Olga I. Goriunova Steven Boyd Benedikt Hallgrímsson M. Anne Katzenberg 《American journal of physical anthropology》2014,154(4):486-497
Bone quality, a contributor to bone strength, is determined by structural and mechanical properties, which may be analyzed by gross and/or microscopic methods. Variables that contribute to bone quality, such as porosity, can provide insight into the health and lifestyles of people in prehistory. This study tests the ability of microcomputed tomography (µCT) to capture and characterize cortical canal systems in archaeological bone. Seven variables and 71 femora are analyzed to explore bone dynamics in prehistoric foragers from Lake Baikal, Siberia. The results indicate that canal number and canal separation differ significantly (P < 0.05) between age‐at‐death categories, but only for the pooled and male samples. When merged into a new variable by means of principal components analysis, canal diameter and canal surface to canal volume are also able to discriminate amongst age‐at‐death categories, as well as between the sexes. However, the overall lack of significant differences between the sexes and amongst age‐at‐death categories indicates that Baikal forager bone quality (i.e., canal architecture) did not change drastically throughout the lifespan. Interestingly, principal component one identified an untested variable that contributes to canal microstructure variability, and a sexual division of labor may promote divergent trends in canal degree of anisotropy between the sexes. Overall, µCT provides an alternate method for exploring bone quality in archaeological remains, complementing existing methods such as thin‐sectioning and gross morphological analyses. Am J Phys Anthropol 154:486–497, 2014. © 2014 Wiley Periodicals, Inc. 相似文献
15.
This article outlines how to incorporate argumentation into a forensic science unit using a mock trial. Practical details of the mock trial include: (1) a method of scaffolding students’ development of their argument for the trial, (2) a clearly outlined set of expectations for students during the planning and implementation of the mock trial, and (3) an example of how to use questioning to guide students through the planning of the mock trial. While a general forensic science unit is provided in the article, a teacher can use the details of the mock trial with any forensic science unit for either middle school or secondary science students. 相似文献
16.
目的:研究成人尺桡骨中上段双骨折使用背侧单切口与桡尺侧双切口钢板内固定的治疗效果。方法:选择我院2011年3月至2014年7月行双钢板治疗成年尺桡骨中上段双骨折患者41例,其中手术入路选择背侧单切口患者25例,选择背侧双切口患者16例。比较两种手术方式的临床效果。结果:背侧单切口入路组患者在手术出血、切口长度等方面要优于背侧双切口组(P0.01);两组在术前时间、骨折愈合时间方面未见明显差异(P0.05)。单切口组的疼痛VAS评分在术后1周和术后12周时要优于双切口组(P0.05);单切口组的膝关节HSS评分在术后1周时要优于双切口组(P0.01),而在术后12周时两组未见明显差异(P0.05)。结论:选择背侧入路单切口和双切口双钢板治疗尺桡骨中上段双骨折均有较好的临床效果,而背侧单切口入路,手术操作相对简单易行,创伤较小,术后恢复较好。 相似文献
17.
Th. Bächi Kathryn Whiting M.J.A. Tanner M.N. Metaxas D.J. Anstee 《生物化学与生物物理学报:生物膜》1977,464(3):635-639
Human erythrocytes of blood group En (a-), a rare homozygous condition involving a complete lack of the major sialoglycoprotein of the cell membrane (glycophorin A), were compared with erythrocytes from normal (En(a+)) individuals by freeze-fracture electron microscopy. No decrease in number, or variation in morphology, of the intramembranal particles of En (a-) cells was detectable. These results show that the erythrocyte sialoglycoprotein is not essential for the maintenance of the integrity of the intramembranal particles of the human erythrocyte membrane. 相似文献
18.
The ear drum, or tympanic membrane (TM), is a key component in the intricate relay that transmits air‐borne sound to our fluid‐filled inner ear. Despite early belief that the mammalian ear drum evolved as a transformation of a reptilian drum, newer fossil data suggests a parallel and independent evolution of this structure in mammals. The term “drum” belies what is in fact a complex three‐dimensional structure formed from multiple embryonic cell lineages. Intriguingly, disease affects the ear drum differently in its different parts, with the superior and posterior parts being much more frequently affected. This suggests a key role for the developmental details of TM formation in its final form and function, both in homeostasis and regeneration. Here we review recent studies in rodent models and humans that are beginning to address large knowledge gaps in TM cell dynamics from a developmental biologist's point of view. We outline the biological and clinical uncertainties that remain, with a view to guiding the indispensable contribution that developmental biology will be able to make to better understanding the TM. 相似文献
19.
本文记述了产自江苏泗洪的一鹫类(Vultures)跗跡骨化石——顾氏中新鹫Mioaegypius gui gen.et sp.nov.填补了欧亚大陆中新世大型食肉鸟类的空白。 相似文献
20.
Because teaching and learning are regulated by distinct ideas of education and school administration in each of the sixteen states in Germany, an analysis of arts and music education policy shows contradictory results. However, this article reveals that an underlying discourse on the role and importance of music education draws a more homogenous picture. Therefore, the article focuses on parents’ attitudes toward music education within the frame of mobility German society offers. It is shown that middle class parents especially value music as part of a strategy to secure children's future status. On a higher level again this leads to contradictions between verbalized positions on the aims of music education and factual decisions. These contradictions are framed by more general theories on policymaking in a global perspective. 相似文献