Comparison of different designs of implant-retained overdentures and fixed full-arch implant-supported prosthesis on stress distribution in edentulous mandible - A computed tomography-based three-dimensional finite element analysis

A finite element analysis was used to compare the effect of different designs of implant-retained overdentures and fixed full-arch implant-supported prosthesis on stress distribution in edentulous mandible. Four models of an human mandible were constructed. In the OR (O'ring) group, the mandible was restored with an overdenture retained by four unsplinted implants with O'ring attachment; in the BC (bar-clip) -C and BC groups, the mandibles were restored with overdentures retained by four splinted implants with bar-clip anchor associated or not with two distally placed cantilevers, respectively; in the FD (fixed denture) group, the mandible was restored with a fixed full-arch four-implant-supported prosthesis. Models were supported by the masticatory muscles and temporomandibular joints. A 100-N oblique load was applied on the left first molar. Von Mises (σvM), maximum (σmax) and minimum (σmin) principal stresses (in MPa) analyses were obtained. BC-C group exhibited the highest stress values (σvM=398.8, σmax=580.5 and σmin=-455.2) while FD group showed the lowest one (σvM=128.9, σmax=185.9 and σmin=-172.1). Within overdenture groups, the use of unsplinted implants reduced the stress level in the implant/prosthetic components (59.4% for σvM, 66.2% for σmax and 57.7% for σmin versus BC-C group) and supporting tissues (maximum stress reduction of 72% and 79.5% for σmax, and 15.7% and 85.7% for σmin on the cortical and trabecular bones, respectively). Cortical bone exhibited greater stress concentration than the trabecular bone for all groups. The use of fixed implant dentures and removable dentures retained by unsplinted implants to rehabilitate edentulous mandible reduced the stresses in the periimplant bone tissue, mucosa and implant/prosthetic components. © 2013 Elsevier Ltd.

Small-angle X-ray scattering and structural modeling of full-length: Cellobiohydrolase I from Trichoderma harzianum

Cellobiohydrolases hydrolyze cellulose releasing cellobiose units. They are very important for a number of biotechnological applications, such as, for example, production of cellulosic ethanol and cotton fiber processing. The Trichoderma cellobiohydrolase I (CBH1 or Cel7A) is an industrially important exocellulase. It exhibits a typical two domain architecture, with a small C-terminal cellulose-binding domain and a large N-terminal catalytic core domain, connected by an O-glycosylated linker peptide. The mechanism by which the linker mediates the concerted action of the two domains remains a conundrum. Here, we probe the protein shape and domain organization of the CBH1 of Trichoderma harzianum (ThCel7A) by small angle X-ray scattering (SAXS) and structural modeling. Our SAXS data shows that ThCel7A linker is partially-extended in solution. Structural modeling suggests that this linker conformation is stabilized by inter- and intra-molecular interactions involving the linker peptide and its O-glycosylations. © 2013 Springer Science+Business Media Dordrecht.

Subregional preparations for the 2004 international meeting that will undertake a full and comprehensive review of the implementation of the SIDS POA to ensure the most effective participation of Caribbean SIDS

In Part XV (Implementation Monitoring and Review);, of the Programme of Action of Small Island Developing States (SIDS POA);, which was adopted at the United Nations Global Conference on the Sustainable Development of Small Island Developing States (UNGCSIDS);, 26 April- 6 May 1994, in its paragraph 117, it is provided that the Commission on Sustainable Development (CSD); should, inter alia: Carry out an initial review of the progress achieved and steps taken to implement the Programme of Action, to be undertaken by the Commission on Sustainable Development in 1996 in accordance with its Multi-Year Thematic Programme of Work. Furthermore, in 1997, when the Commission will carry out the overall review of Agenda 21 with a view to preparing for the 1997 special session of the General Assembly, the Commission should recommend specific modalities for the full review of the Programme of Action in 1999. That full review would include the question of the convening of a second global conference in accordance with chapter 17, Section G of Agenda 21. At the twenty-second special session which convened on 27-28 September 1999 to undertake a "review and appraisal of the implementation of the Programme of Action for the Sustainable Development of Small Island Developing States", it was recommended, inter alia, that: "Although periodic reviews of certain aspects of the Programme of Action are envisaged within the context of the work of the Commission on Sustainable Development, a full and comprehensive review of these decisions and the implementation of the Programme of Action would be useful and required in 2004." In the Plan of Implementation adopted at the World Summit on Sustainable Development (WSSD);, which convened in Johannesburg, South Africa, over the period, 26 August-4 Septemeber 2002, the relevant recommendation was as follows: "Undertake a full and comprehensive review of the implementation of the Barbados Programme of Action for the Sustainable Development of Small Island Developing States in 2004, in accordance with the provisions set forth in General Assembly resolution S-22/2, and in this context requests the General Assembly at its fifty-seventh session to consider convening an international meeting for the sustainable development of small island developing States."

The influence of bone quality on the biomechanical behavior of full-arch implant-supported fixed prostheses

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

The role of superstructure material on the stress distribution in mandibular full-arch implant-supported fixed dentures. A CT-based 3D-FEA

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Non-linear 3D finite element analysis of full-arch implant-supported fixed dentures

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Experimental full-thickness burns induced by CO2 laser

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Short-term cycles of feed deprivation and refeeding promote full compensatory growth in the Amazon fish matrinxa (Brycon amazonicus)

Developing nutritional strategies that can reduce production costs for the fish industry without affecting productive performance is paramount to make the activity sustainable. We investigated if short-term cycles of feed deprivation and refeeding elicit compensatory growth in matrinxa (Brycon amazonicus) juveniles, using three feeding protocols for 60 days (Phase 1): two levels of deprivation (feed deprivation for two days and refeeding for three - D2R3, or four days - D2R4) and a control level (daily feeding). Following, all fish groups were fed daily at satiation for 15 days (Phase 2). At Phase 1, matrinxa achieved full compensatory growth in both deprivation levels by increasing feed intake and feed efficiency. Overall, deprived fish consumed 40% (D2R3) and 36% (D2R4) less feed than fish fed daily. In Phase 2, growth was similar for all fish. Feed intake increased in both deprived fish, but feed efficiency did not differ among groups and was lower than in Phase 1, indicating a reduced efficiency in feed utilization when food was freely available. We propose that intermittent cycles of feeding represent an effective means to reduce production costs. (C) 2014 Elsevier B.V. All rights reserved.

Constructions of ideal lattices with full diversity

In this paper, we present new constructions of ideal lattices for the Rayleigh fading channel in Euclidean spaces with full diversity. These constructions are through totally real subfields of cyclotomic fields, obtained by endowing their ring of integers. With this method we reproduce rotated versions of algebraic lattices where the performance in terms of minimum product distance is related with the field determinant.

Hopf bifurcation in the full repressilator equations

In this paper, we prove that the full repressilator equations in dimension six undergo a supercritical Hopf bifurcation.

A Tool Box Half Full: How Social Science can Help Solve Human–Wildlife Conflict

There is a growing recognition among wildlife managers that focusing management on wildlife often provides a temporary fix to human–wildlife conflicts, whereas changing human behavior can provide long-term solutions. Human dimensions research of wildlife conflicts frequently focuses on stakeholders’ characteristics, problem identification, and acceptability of management, and less frequently on human behavior and evaluation of management actions to change that behavior. Consequently, little information exists to assess overall success of management. We draw on our experience studying human–bear conflicts, and argue for more human dimensions studies that focus on change in human behavior to measure management success. We call for help from social scientists to conduct applied experiments utilizing two methods, direct observation and self-reported data, to measure change in behavior. We are optimistic these approaches will help fill the managers’ tool box and lead to better integration of human dimensions into human–wildlife conflict management.

Expression of soluble and functional full-length human matrix metalloproteinase-2 in Escherichia coli

Characterization of the matrix metalloproteinase-2 (MMP-2) substrates and understanding of its function remain difficult because up to date preparations containing minor amounts of other eukaryotic proteins that are co-purified with MMP-2 are still used. In this work, the expression of a soluble and functional full-length recombinant human MMP-2 (rhMMP-2) in the cytoplasm of Escherichia coli is reported, and the purification of this metalloproteinase is described. Culture of this bacterium at 18 degrees C culminated in maintenance of the soluble and functional rhMMP-2 in the soluble fraction of the E. coli lysate and its purification by affinity with gelatin-sepharose yielded approximately 0.12 mg/L of medium. Western Blotting and zymographic analysis revealed that the most abundant form was the 72-kDa MMP-2, but some gelatinolytic bands corresponding to proteins with lower molecular weight were also detected. The obtained rhMMP-2 was demonstrated to be functional in a gelatinolytic fluorimetric assay, suggesting that the purified rhMMP-2 was correctly folded. The method described here involves fewer steps, is less expensive, and is less prone to contamination with other proteinases and MMP inhibitors as compared to expression of rhMMP-2 in eukaryotic tissue culture. This protocol will facilitate the use of the full-length rhMMP-2 expressed in bacteria and will certainly help researchers to acquire new knowledge about the substrates and biological activities of this important proteinase. (C) 2011 Elsevier B.V. All rights reserved.

From Sample Processing to Quantification: A Full Electrochemical Approach for Neutral Analyte Derivatization, Capillary Electrophoresis Separation, and Contactless Conductivity Detection

A thin-layer electrochemical flow cell coupled to capillary electrophoresis with contactless conductivity detection (EC-CE-(CD)-D-4) was applied for the first time to the derivatization and quantification of neutral species using aliphatic alcohols as model compounds. The simultaneous electrooxidation of four alcohols (ethanol, 1-propanol, 1-butanol, and 1-pentanol) to the corresponding carboxylates was carried out on a platinum working electrode in acid medium. The derivatization step required 1 min at 1.6 V vs. Ag/AgCl under stopped flow conditions, which was preceded by a 10 s activation at 0 V. The solution close to the electrode surface was then hydrodynamically injected into the capillary, and a 2.5 min electrophoretic separation was carried out. The fully automated flow system operated at a frequency of 12 analyses per hour. Simultaneous determination of the four alcohols presented detection limits of about 5 x 10(-5) mol As a practical application with a complex matrix, ethanol concentrations were determined in diluted pale lager beer and in nonalcoholic beer. No statistically significant difference was observed between the EC-CE-(CD)-D-4 and gas chromatography with flame ionization detection (GC-FID) results for these samples. The derivatization efficiency remained constant over several hours of continuous operation with lager beer samples (n = 40).