Integrated taphonomy in an open-marine platform: The Lower Cretaceous of Sierra Helada (Betic Cordillera, SE Spain)

A detailed taphonomic analysis was carried out on the lower Albian deposits of the Sierra Helada section (Alicante, Betic Cordillera, southeastern Spain). Ten taphonomic characters were studied and ten skeletal concentrations were defined on the basis of taphonomic features and the dominant taxa. Cluster analysis was performed on the dataset represented by the abundance of the taphonomic characters in each skeletal concentration. This enabled the definition of four different taphonomic categories: 1) skeletal concentrations characterized by the presence of fossils preserved in life position, 2) skeletal concentrations showing very little physical reworking, 3) skeletal concentrations related to high-energy background conditions, and 4) skeletal concentrations produced by medium- to high-energy events. Four taphofacies were defined on the basis of the main sedimentological features and the most representative skeletal concentrations. Taphofacies A represents the low energy outer platform, rich in skeletal concentrations with echinoids in life position and only slightly reworked. The second taphofacies (taphofacies B) is very rich in reworked echinoid tests and calcarenitic beds and records the transition to shallower areas, while taphofacies C shows abundant thick-bedded calcarenites and skeletal concentrations produced by sediment transport and rapid deposition. Finally, cross-bedded grainstone beds, which are rich in fine-grained fragmented, locally reoriented bioclasts (taphofacies D), record the existence of shifting sandy dunes in the shallow inner part of the platform.

Orbscan Topography in Primary Open-Angle Glaucoma

Purpose: To compare anterior and posterior corneal curvatures between eyes with primary open-angle glaucoma (POAG) and healthy eyes. Methods: This is a prospective, cross-sectional, observer-masked study. A total of 138 white subjects (one eye per patient) were consecutively recruited; 69 eyes had POAG (study group), and the other 69 comprised a group of healthy control eyes matched for age and central corneal pachymetry with the study ones. Exclusion criteria included any corneal or ocular inflammatory disease, previous ocular surgery, or treatment with carbonic anhydrase inhibitors. The same masked observer performed Goldmann applanation tonometry, ultrasound pachymetry, and Orbscan II topography in all cases. Central corneal thickness, intraocular pressure, and anterior and posterior topographic elevation maps were analyzed and compared between both groups. Results: Patients with POAG had greater forward shifting of the posterior corneal surface than that in healthy control eyes (p < 0.01). Significant differences in anterior corneal elevation between controls and POAG eyes were also found (p < 0.01). Conclusions: Primary open-angle glaucoma eyes have a higher elevation of the posterior corneal surface than that in central corneal thickness–matched nonglaucomatous eyes.

Imaging of spin waves in atomically designed nanomagnets

The spin dynamics of all ferromagnetic materials are governed by two types of collective phenomenon: spin waves and domain walls. The fundamental processes underlying these collective modes, such as exchange interactions and magnetic anisotropy, all originate at the atomic scale. However, conventional probing techniques based on neutron1 and photon scattering2 provide high resolution in reciprocal space, and thereby poor spatial resolution. Here we present direct imaging of standing spin waves in individual chains of ferromagnetically coupled S = 2 Fe atoms, assembled one by one on a Cu2N surface using a scanning tunnelling microscope. We are able to map the spin dynamics of these designer nanomagnets with atomic resolution in two complementary ways. First, atom-to-atom variations of the amplitude of the quantized spin-wave excitations are probed using inelastic electron tunnelling spectroscopy. Second, we observe slow stochastic switching between two opposite magnetization states3, 4, whose rate varies strongly depending on the location of the tip along the chain. Our observations, combined with model calculations, reveal that switches of the chain are initiated by a spin-wave excited state that has its antinodes at the edges of the chain, followed by a domain wall shifting through the chain from one end to the other. This approach opens the way towards atomic-scale imaging of other types of spin excitation, such as spinon pairs and fractional end-states5, 6, in engineered spin chains.

Anglicisms and calques in upper social class in pre-revolutionary Cuba (1930–1959): A sociolinguistic analysis

The geographical proximity and socioeconomic dependence on the United States brought about a deep rooted anglicization of the Cuban Spanish lexis and social strata, especially throughout the Neocolonial period (1902–1959). This study is based on the revision of a renowned newspaper of that time, Diario de la Marina, and the corresponding elaboration of a corpus of English-induced loanwords. Diario de la Marina particularly targeted upper social class, and only crónicas sociales (society pages’ columns) and print advertising were revised because of their fully descriptive texts, which encoded the ruling class ideology and consumerism. The findings show that there existed a high number of lexical and cultural anglicisms in the sociolect in question, and that the sociolinguistic anglicization was openly embraced by the upper socioeconomic stratum, entailing a differentiating sign of sophistication and social stratification. Likewise, a number of the anglicisms collected, particularly those related with social events, are unused in contemporary Cuban Spanish, which suggests a major semantic shifting in this sociolect after 1959.