Uma estética do paradoxo: aspectos do melodrama no romance latino-americano do pós-boom

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Evaluation of the efficiencies of helical anchor plates in sand by centrifuge model tests

The uplift capacity of helical anchors normally increases with the number of helical plates. The rate of capacity gain is variable, considering that the disturbance caused by the anchor installation is generally more pronounced in the soil mass above the upper plates than above the lower plates, because the upper soil layers are penetrated more times. The present investigation examines the effect of the number of helices on the performance of helical anchors in sand, based on the results of centrifuge model tests. Uplift loading tests were performed on 12 different types of piles installed in two containers of dry sand prepared with different densities. The measured fractions of the uplift capacity related to each individual helical plate of multi-helix anchors were compared with the fractions predicted by the individual bearing method. The results of this investigation indicate that in double- and triple-helix anchors, the contributions of the second and third plate to the total anchor uplift capacity decreased with the increase of sand relative density and plate diameter. In addition, these experiments demonstrated that the variation of the anchor load-displacement behavior with the number of helices also depends on these parameters.

Finite element analysis of stress distribution in anchor teeth in surgically assisted rapid palatal expansion

The treatment of a transverse maxillary deficiency in skeletally mature individuals should include surgically assisted rapid palatal expansion. This study evaluated the distribution of stresses that affect the expander's anchor teeth using finite element analysis when the osteotomy is varied. Five virtual models were built and the surgically assisted rapid palatal expansion was simulated. Results showed tension on the lingual face of the teeth and alveolar bone, and compression on the buccal side of the alveolar bone. The subtotal Le Fort I osteotomy combined with intermaxillary suture osteotomy seemed to reduce the dissipation of tensions. Therefore, subtotal Le Fort I osteotomy without a step in the zygomaticomaxillary buttress, combined with intermaxillary suture osteotomy and pterygomaxillary disjunction may be the osteotomy of choice to reduce tensions on anchor teeth, which tend to move mesiobuccally (premolar) and distobuccally (molar)

A molecular approach towards tethered bilayer lipid membranes: synthesis and characterization of novel anchor lipids

Tethered bilayer lipid membranes (tBLMs) are a promising model system for the natural cell membrane. They consist of a lipid bilayer that is covalently coupled to a solid support via a spacer group. In this study, we developed a suitable approach to increase the submembrane space in tBLMs. The challenge is to create a membrane with a lower lipid density in order to increase the membrane fluidity, but to avoid defects that might appear due to an increase in the lateral space within the tethered monolayers. Therefore, various synthetic strategies and different monolayer preparation techniques were examined. Synthetical attempts to achieve a large ion reservoir were made in two directions: increasing the spacer length of the tether lipids and increasing the lateral distribution of the lipids in the monolayer. The first resulted in the synthesis of a small library of tether lipids (DPTT, DPHT and DPOT) characterized by 1H and 13C NMR, FD-MS, ATR, DSC and TGA. The synthetic strategy for their preparation includes synthesis of precursor with a double bond anchor that can be easily modified for different substrates (e.g. metal and metaloxide). Here, the double bond was modified into a thiol group suitable for gold surface. Another approach towards the preparation of homogeneous monolayers with decreased two-dimensional packing density was the synthesis of two novel anchor lipids: DPHDL and DDPTT. DPHDL is “self-diluted” tether lipid containing two lipoic anchor moieties. DDPTT has an extended lipophylic part that should lead to the preparation of diluted, leakage free proximal layers that will facilitate the completion of the bilayer. Our tool-box of tether lipids was completed with two fluorescent labeled lipid precursors with respectively one and two phytanyl chains in the hydrophobic region and a dansyl group as a fluorophore. The use of such fluorescently marked lipids is supposed to give additional information for the lipid distribution on the air-water interface. The Langmuir film balance was used to investigate the monolayer properties of four of the synthesized thiolated anchor lipids. The packing density and mixing behaviour were examined. The results have shown that mixing anchor with free lipids can homogeneously dilute the anchor lipid monolayers. Moreover, an increase in the hydrophylicity (PEG chain length) of the anchor lipids leads to a higher packing density. A decrease in the temperature results in a similar trend. However, increasing the number of phytanyl chains per lipid molecule is shown to decrease the packing density. LB-monolayers based on pure and mixed lipids in different ratio and transfer pressure were tested to form tBLMs with diluted inner layers. A combination of the LB-monolayer transfer with the solvent exchange method accomplished successfully the formation of tBLMs based on pure DPOT. Some preliminary investigations of the electrical sealing properties and protein incorporation of self-assembled DPOT and DDPTT-based tBLMs were conducted. The bilayer formation performed by solvent exchange resulted in membranes with high resistances and low capacitances. The appearance of space beneath the membrane is clearly visible in the impedance spectra expressed by a second RC element. The latter brings the conclusion that the longer spacer in DPOT and the bigger lateral space between the DDPTT molecules in the investigated systems essentially influence the electrical parameters of the membrane. Finally, we could show the functional incorporation of the small ion carrier valinomycin in both types of membranes.

Boom del lusso in Cina: Traduzione e analisi della ricerca di Fortune China nell'ottica della tradizione cinese

Breve introduzione alla cultura tradizionale, concentrandosi su confucianesimo e taoismo; approfondimento in ambito economico sulle tendenze del mercato del lusso in Cina; traduzione di parte dell'articolo di 刘 聪 “中国奢侈品市场走向成熟： 挖掘长线潜能", tratto dal bi-settimanale Fortune China. Il tutto per comprendere lo sviluppo e le caratteristiche del mercato del lusso cinese.

Outcomes following three-line vision loss during treatment of neovascular age-related macular degeneration: subgroup analyses from MARINA and ANCHOR

This study aims to assess the impact of continued ranibizumab treatment for neovascular age-related macular degeneration on patients from the MARINA and ANCHOR randomised clinical studies who lost ≥ 3 lines of best-corrected visual acuity (BCVA) at any time during the first year of treatment.

IS THE U.S. SHALE GAS BOOM HAVING AN EFFECT ON THE EUROPEAN GAS MARKET?

This thesis focuses on the impact of the American shale gas boom on the European natural gas market. The study presents different tests in order to analyze the dynamics of natural gas prices in the U.S., U.K. and German natural gas market. The question of cointegration between these different markets are analyzed using several tests. More specifically, the ADF tests for the presence of a unit root. The error correction model test and the Johansen cointegration procedure are applied in order to accept or reject the hypothesis of an integrated market. The results suggest no evidence of cointegration between these markets. There currently is no evidence of an impact of the U.S. shale gas boom on the European market.

Comparative study of four retentive anchor systems for implant supported overdentures--retention force changes

OBJECTIVES: Wear of attachments leads to a loss of retention and potentially reduces the function of complete dentures. This study evaluated the retention force changes of different prefabricated attachment systems for implant-supported overdentures to estimate the wear constancy and applicability in clinical practice. METHODS: Four prefabricated attachment systems were tested [Group SG: retentive ball attachment (Straumann, Switzerland) with gold matrix, Group ST: retentive ball attachment (Straumann, Switzerland) with titanium spring matrix, Group IB: UNOR i-Ball with Ecco matrix (UNOR, Switzerland) and Group IMZ: IMZ-TwinPlus ball attachment with gold matrix (DENTSPLY Friadent, Germany)]. Ten samples of each system were subjected to 10,000 insertion-separation cycles. RESULTS: Results showed that all types of attachments showed wear, which led to a loss of retention force after an initial increase at the beginning of the wear simulation. Attachments with a plastic retention insert or gold matrices underwent the smallest changes in retention force. The titanium spring system showed the largest changes in retention force and a greater variation between the different cycles and specimen. This behaviour is probably caused by a large fitting tolerance of the titanium spring. CONCLUSIONS: Attachment systems which possess a male and female component of different material composition are preferable. They show smaller changes in the retention force. For retention force increase and wear compensation, an attachment system should be adjustable.

Using Superelements in the Calculation of Lattice-Boom Cranes

In this paper a superelement formulation for geometric nonlinear finite element analysis is proposed. The element formulation is based on matrices generated by the static condensation algorithm. After defining the element characteristics, a method for the calculation of the element forces in a large displacement and rotation analysis is developed. In order to use the element in the solution of stability problems, the formulation of the geometric stiffness matrix is derived. An example shows the benefits of the element for the calculation of lattice-boom cranes.