Gonzalo de Berceo in Spanish Literary Criticism before 1780

In Spanish literature the first poet whose name we know with certainty is Gonzalo de Berceo, who flourished in the first half of the thirteenth century. The first complete edition of his works did not appear until toward the end of the eighteenth century. What happened to them and what was thought of them during the five centuries that intervened between the death of the poet and the year 1780, when the learned Librarian of the King, Don Tomás Antonio Sánchez, published the second volume of his Collección de Poesías Castellanas Anteriores al Siglo XV giving it the subtitle of Poesías de Don Gonzalo de Berceo? The question is not without interest; neither are the results of the investigations that lead us toward the possibility of answering it. Consequently, I propose setting forth with the utmost brevity the results that I have so far been able to obtain from my investigations. In citing the texts that speak of Berceo, I shall not stop to comment on them, nor even to correct the errors–sometimes rather serious-they may contain

Boron nanobelts grown under intensive ion bombardment

High-quality α-tetragonal crystalline boronnanobelts with [001] growth axis were synthesized using a novel method combining e-beam evaporation and plasma ion bombardment techniques. Intensive ion bombardment of the growingboronnanobelts at a high substrate temperature (∼1200°C) was found to be effective in increasing the atomic density, reducing the crystal disorder, and improving the yield of the nanobelts.This work was supported by the Australian Research Council ARC

Effect of implant temperature on secondary defects created by MeV Sn implantation in silicon

Secondary defects induced by ion implantation in silicon after annealing have been previously shown to vary with the implantation and annealing conditions. However, in the low dose implants, well below the amorphization dose, the defects have been predominantly characterized to be interstitial in nature. In this article, we study the effect of implant temperature on secondary defects created by 1 MeV Sn implantation to a dose of 3×10¹³ cm⁻² after subsequent annealing. We report a variation in the defect microstructure with implant temperature showing preferential formation of small interstitial loops for −191 °C and only rod-like defects for similar implants carried out at 300 °C. We conclude that these microstructures are a result of the dense cascades created by heavy Sn ions, creating local amorphous pockets in the implant damage region at the lowest implant temperatures. The variation of the microstructure with implant temperature is interpreted in terms of the effect of dynamic annealing over the defects formed in silicon.One of the authors (J.W-L.) would like to acknowledge the Australian Research Council for financial support under the ARC fellowship program

OH-bearing planar defects in olivine produced by the breakdown of Ti-rich humite minerals from Dabie Shan (China)

The partial breakdown of Ti-chondrodite and Ti-clinohumite during exhumation from ultra-high pressure to amphibolite facies conditions in garnet-pyroxenites from Dabie Shan (China) produces coronas of olivine coexisting with ilmenite blebs. Fourier transform infrared (FTIR) spectra of this newly formed olivine exhibit absorption bands in the hydroxyl-stretching region. Two intense peaks were observed at 3,564 and 3,394 cm-1, identical in energy to peaks in Ti-clinohumite. Transmission electron microscopy (TEM) of the same olivine domains revealed the presence of a complex (001) planar intergrowth. These interlayers have a 1.35 nm repeat distance, which is characteristic of clinohumite. Such interlayers are also enriched in Ti with respect to the adjacent olivine as shown by energy dispersive spectrometry. The combined evidence from FTIR spectroscopy and TEM indicates that OH is incorporated along Ti-clinohumite planar defects. This study provides evidence that the nominally anhydrous phase olivine may contain OH as a humite-type defect beyond the breakdown of the hydrous humite minerals and confirms earlier suggestions that Ti plays a key role in OH incorporation in mantle olivine. We suggest that olivine containing Ti-clinohumite defects is an important phase for water transport in subduction zones and for the storage of water in cold subcontinental mantle. However, these defects are unlikely to be stable in hotter parts of the oceanic mantle such as where basaltic magmas are generated

Unconventional magnetism in all-carbon nanofoam

We report production of nanostructured carbon foam by a high-repetition-rate, high-power laser ablation of glassy carbon in Ar atmosphere. A combination of characterization techniques revealed that the system contains both sp2 and sp3 bonded carbon atoms. The material is a novel form of carbon in which graphite-like sheets fill space at very low density due to strong hyperbolic curvature, as proposed for ?schwarzite?. The foam exhibits ferromagnetic-like behaviour up to 90 K, with a narrow hysteresis curve and a high saturation magnetization. Such magnetic properties are very unusual for a carbon allotrope. Detailed analysis excludes impurities as the origin of the magnetic signal. We postulate that localized unpaired spins occur because of topological and bonding defects associated with the sheet curvature, and that these spins are stabilized due to the steric protection offered by the convoluted sheets.Comment: 14 pages, including 2 tables and 7 figs. Submitted to Phys Rev B 10 September 200

Adjuvant drugs for peripheral nerve blocks: The role of nmda antagonists, neostigmine, epinephrine, and sodium bicarbonate

The potential for misuse, overdose, and chronic use has led researchers to look for other methods to decrease opioid consumption in patients with acute and chronic pain states. The use of peripheral nerve blocks for surgery has gained increasing popularity as it minimizes peripheral pain signals from the nociceptors of local tissue sustaining trauma and inflammation from surgery. The individualization of peripheral nerve blocks using adjuvant drugs has the potential to improve patient outcomes and reduce chronic pain. The major limitations of peripheral nerve blocks are their limited duration of action and dose-dependent adverse effects. Adjuvant drugs for peripheral nerve blocks show increasing potential as a solution for postoperative and chronic pain with their synergistic effects to increase the duration of action and decrease the required dosage of local anesthetic. N-methyl-d-aspartate (NMDA) receptor antagonists are a viable option for patients with opioid resistance and neuropathic pain due to their affinity to the neurotransmitter glutamate, which is released when patients experience a noxious stimulus. Neostigmine is a cholinesterase inhibitor that exerts its effect by competitively binding at the active site of acetylcholinesterase, which prevents the hydrolysis of acetylcholine and subsequently retaining acetylcholine at the nerve terminal. Epinephrine, also known as adrenaline, can potentially be used as an adjuvant to accelerate and prolong analgesic effects in digital nerve blocks. The theorized role of sodium bicarbonate in local anesthetic preparations is to increase the pH of the anesthetic. The resulting alkaline solution enables the anesthetic to more readily exist in its un-ionized form, which more efficiently crosses lipid membranes of peripheral nerves. However, more research is needed to show the efficacy of these adjuvants for nerve block prolongation as studies have been either mixed or have small sample sizes

Stacking faults and superstructures in a layered brownmillerite

Stacking faults in Ca4Fe2Mn0.5Ti0.5O9 have been examined using X-ray diffraction and high-resolution transmission electron microscopy. Electron diffraction revealed two superstructures with ordered stacking sequences

Expenditure Reform in Industrialised Countries: A Case Study Approach

This study examines reforms of public expenditure in industrialised countries over the past two decades. We distinguish ambitious and timid reformers and analyse in detail reform experiences in eight case studies of ambitious reform episodes. We find that ambitious reform countries reduce spending on transfers, subsidies and public consumption while largely sparing education spending. Such expenditure retrenchment is also typically part of a comprehensive reform package that includes improvements in fiscal institutions as well as structural and other macroeconomic reforms. The study finds that ambitious expenditure retrenchment and reform coincides with large improvements in fiscal and economic growth indicators