Er:YAG-Laser and Sodium Hypochlorite Influence on Bond to Dentin

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

Effect of Post-silanization Heat Treatments of Silanized Feldspathic Ceramic on Adhesion to Resin Cement

Purpose: To evaluate the effect of post-silanization heat treatment of a silane agent and rinsing with hot water of silanized CAD/CAM feldspathic ceramic surfaces on the microtensile bond strength between resin cement and the ceramic, before and after mechanical cycling.Materials and Methods: Blocks measuring 10 x 5.7 x 3.25 mm(3) were produced from feldspathic ceramic cubes (VITA Mark II, VITA Zanhfabrik). Each ceramic block was duplicated in composite resin using a template made of polyvinylsiloxane impression material. Afterwards, ceramic and corresponding resin composite blocks were ultrasonically cleaned and randomly divided according to the 5 strategies used for conditioning the ceramic surface (n = 10): GHF: etching with hydrofluoric acid 10% + rinsing with water at room temperature + silanization at 20 degrees C; G20: silanization; G77: silanization + oven drying at 77 degrees C; G20r: silanization + hot water rinsing; G77r: silanization + oven drying at 77 C + hot water rinsing. The resin and ceramic blocks were cemented using a dual-curing resin cement. Every group was divided in two subgroups: aging condition (mechanical cycling, designated as a) or non-aging (designated as n). All the bonded assemblies were sectioned into microsticks for microtensile bond strength (mu TBS) testing. The failure mode of the tested specimens was assessed and mu TBS data were statistically analyzed in two ways: first 2-way ANOVA (GHF, G20 and G77 in non-aging/aging conditions) and 3-way ANOVA (temperature x rinsing x aging factors, excluding GHF), followed by Tukey's test (p = 0.05).Results: The 2-way ANOVA revealed that the mu TBS was significantly affected by the surface treatment (p < 0.001) but not by aging (p = 0.68), and Tukey's test showed that G77-n/G77-a (18.0 MPa) > GHF-n/GHF-a (12.2 MPa) > G20-n/G20-a (9.1 MPa). The 3-way ANOVA revealed that the mu TBS was significantly affected by the heat treatment and rinsing factors (p < 0.001), but not affected by aging (p = 0.36). The rinsing procedure decreased, while oven drying increased the bond strengths. Group G77, in both non-aging and aging conditions (18.6-17.4 MPa), had the highest bond values. Failure modes were mainly mixed for all groups.Conclusion: Oven drying at 77 degrees C improved the bond strength between the resin cement and feldspathic ceramic, but hot water rinsing reduced the bond strength and should not be recommended.

Student's academic efficacy or Inefficacy? an example on how to evaluate the psychometric properties of a measuring instrument and evaluate the effects of item wording

This study evaluated the effect of item inversion on the construct validity and reliability of psychometric scales and proposed a theoretical framework for the evaluation of the psychometric properties of data gathered with psychometric instruments. To this propose, we used the Maslach Burnout Inventory, which is the most used psychometric inventory to measure burnout in different professional context (Students, Teachers, Police, Doctors, Nurses, etc…). The version of the MBI used was the MBI-Student Survey (MBI-SS). This inventory is composed of three key dimensions: Exhaustion, Cynicism and Professional Efficacy. The two first dimensions—which have positive formulated items—are moderate to strong positive correlated, and show moderate to strong negative correlations with the 3rd dimension—which has negative formulated items. We tested the hypothesis that, in college students, formulating the 3rd dimension of burnout as Inefficacy (reverting the negatively worded items in the Efficacy dimension) improves the correlation of the 3rd dimension with the other two dimensions, improves its internal consistency, and the overall MBI-SS’ construct validity and reliability. Confirmatory factor analysis results, estimated by Maximum Likelihood, revealed adequate factorial fit for both forms of the MBI-SS (with Efficacy) vs. the MBI-SSi (with Inefficacy). Also both forms showed adequate convergent and discriminant related validity. However, reliability and convergent validity were higher for the MBI-SSi. There were also stronger (positive) correlations between the 3 factors in MBI-SSi than the ones observed in MBI-SS. Results show that positively rewording of the 3rd dimension of the MBI-SS improves its validity and reliability. We therefore propose that the 3rd dimension of the MBI-SS should be named Professional Inefficacy and its items should be positively worded.

African American Student Access To and Completion Of Higher Education, 1960-1992: A Correspondence Theory Analysis

“This presentation utilizes correspondence theory to analyze African American undergraduate student access to and completion of higher education in the United States. Findings from this research are presented and policy recommendations affecting Black student enrollment and graduation are discussed.”

Effects of Matrix Metalloproteinase (MMP)-2 Polymorphisms on Responsiveness to Antihypertensive Therapy of Women with Hypertensive Disorders of Pregnancy

Imbalanced matrix metalloproteinase (MMP) expression, including MMP-2, has been demonstrated in pre-eclampsia. However, little is known about the effect of polymorphisms in MMP-2 gene on hypertensive disorders of pregnancy. We examined whether two functional MMP-2 polymorphisms (g.-1306C>T and g.-735C>T) are associated with pre-eclampsia and/or gestational hypertension and whether these polymorphisms affect therapeutic responses in women with these conditions. We studied 216 healthy pregnant women (HP), 185 patients with gestational hypertension (GH) and 216 patients with pre-eclampsia (PE). They were stratified as responsive or non-responsive to antihypertensive therapy according to clinical and laboratorial parameters of therapeutic responsiveness. Genomic DNA was extracted from whole blood and genotypes for g-1306C>T and g.-735C>T polymorphisms were determined by real-time PCR using Taqman allele discrimination assays. Haplotype frequencies were inferred using the PHASE 2.1 program. The distributions of MMP-2 genotypes and haplotypes were similar in HP, GH and PE patients (p > 0.05). In addition, we found no significant differences in MMP-2 genotype or haplotype frequencies when GH or PE patients were classified as responsive or non-responsive to antihypertensive therapy (p > 0.05). Our results suggest that MMP-2 polymorphisms do not affect the susceptibility to hypertensive disorders of pregnancy. In parallel, MMP-2 polymorphisms apparently do not affect the responsiveness to antihypertensive therapy of women with these hypertensive disorders of pregnancy.

Direct Access to Oxidation-Resistant Nickel Catalysts through an Organometallic Precursor

The synthesis of nickel catalysts for industrial applications is relatively simple; however, nickel oxidation is usually difficult to avoid, which makes it challenging to optimize catalytic activities, metal loadings, and high-temperature activation steps. A robust, oxidation-resistant and very active nickel catalyst was prepared by controlled decomposition of the organometallic precursor [bis(1,5-cyclooctadiene)nickel(0)], Ni(COD)(2), over silica-coated magnetite (Fe3O4@SiO2). The sample is mostly Ni(0), and surface oxidized species formed after exposure to air are easily reduced in situ during hydrogenation of cyclohexene under mild conditions recovering the initial activity. This unique behavior may benefit several other reactions that are likely to proceed via Ni heterogeneous catalysis.

Post-trial access to study medication: a Brazilian e-survey with major stakeholders in clinical research

Objectives To analyse the perspective of clinical research stakeholders concerning post-trial access to study medication. Methods Questionnaires and informed consents were sent through e-mail to 599 ethics committee (EC) members, 290 clinical investigators (HIV/AIDS and Diabetes) and 53 sponsors in Brazil. Investigators were also asked to submit the questionnaire to their research patients. Two reminders were sent to participants. Results The response rate was 21%, 20% and 45% in EC, investigators and sponsors' groups, respectively. 54 patients answered the questionnaire through their doctors. The least informative item in the consent form was how to obtain the study medication after trial. If a benefit were demonstrated in the study, 60% of research participants and 35% of EC answered that all patients should continue receiving study medication after trial; 43% of investigators believed the medication should be given to participants, and 40% to subjects who participated and benefited from treatment. For 50% of the sponsors, study medication should be assured to participants who had benefited from treatment. The majority of responders answered that medication should be provided free by sponsors; investigators and sponsors believed the medication should be kept until available in the public health sector; EC members said that the patient should keep the benefit; patients answered that benefits should be assured for life. Conclusions Due to the study limitations, the results cannot be generalised; however, the data can contribute to discussion of this complex topic through analysing the views of stakeholders in clinical research in Brazil.

Access to healthcare services for tuberculosis: analysis of patient satisfaction

Tuberculosis remains a pubic health challenge. Uncountable efforts are made to control the disease, and patient treatment and accessibility to healthcare can hinder reaching a cure. The objective of this article is to analyze the satisfaction of tuberculosis patients regarding tuberculosis control services. This is an epidemiological, prospective study, using both a quantitative and qualitative approach. Data were collected using a semi-structured questionnaire. Participants included 77 patients. The quantitative data were positively evaluated, and the qualitative data permitted an understanding of the patients' experience regarding their accessibility and treatment. Aspects such as the criteria for performing Directly Observed Treatment and the proximity of the healthcare facility to the patients' residence affected their satisfaction, which implies the need to reorganize healthcare services in order to provide more appropriate care to tuberculosis patients.

Oral health and access to dental care services in relation to the Health Necessities Index. Sao Paulo, Brazil, 2008

The Health Department of Sao Paulo, Brazil, has developed a Health Necessities Index (HNI) to identify priority areas for providing health assistance. In 2008, a survey of the status of oral health was conducted. The objective of this ecological study was to analyze the status of oral health in relation to the HNI. The variables, stratified by the age of 5, 12 and 15 years old were: percentage of individuals with difficulty of access to dental care services; DMFT and DMFS; prevalence of the need for tooth extraction and treatment of dental caries. Data were analyzed for the 25 Health Technical Supervision Units (HTS). The Statistical Covariance Test was used as well as the Pearson correlation coefficient and linear regression model. A positive correlation was observed between high scores of the HNI and difficulty of access to services. In the HTS with high scores of HNI a higher incidence of dental caries was observed, a greater need for tooth extractions and low caries-free incidence. In order to improve health conditions of the population it is mandatory to prioritize actions in areas of social deprivation.

"Water users must be efficient producers". Women's access to and use of land in Chókwè irrigation scheme, Mozambique

The irrigation scheme Eduardo Mondlane, situated in Chókwè District - in the Southern part of the Gaza province and within the Limpopo River Basin - is the largest in the country, covering approximately 30,000 hectares of land. Built by the Portuguese colonial administration in the 1950s to exploit the agricultural potential of the area through cash-cropping, after Independence it became one of Frelimo’s flagship projects aiming at the “socialization of the countryside” and at agricultural economic development through the creation of a state farm and of several cooperatives. The failure of Frelimo’s economic reforms, several infrastructural constraints and local farmers resistance to collective forms of production led to scheme to a state of severe degradation aggravated by the floods of the year 2000. A project of technical rehabilitation initiated after the floods is currently accompanied by a strong “efficiency” discourse from the managing institution that strongly opposes the use of irrigated land for subsistence agriculture, historically a major livelihood strategy for smallfarmers, particularly for women. In fact, the area has been characterized, since the end of the XIX century, by a stable pattern of male migration towards South African mines, that has resulted in an a steady increase of women-headed households (both de jure and de facto). The relationship between land reform, agricultural development, poverty alleviation and gender equality in Southern Africa is long debated in academic literature. Within this debate, the role of agricultural activities in irrigation schemes is particularly interesting considering that, in a drought-prone area, having access to water for irrigation means increased possibilities of improving food and livelihood security, and income levels. In the case of Chókwè, local governments institutions are endorsing the development of commercial agriculture through initiatives such as partnerships with international cooperation agencies or joint-ventures with private investors. While these business models can sometimes lead to positive outcomes in terms of poverty alleviation, it is important to recognize that decentralization and neoliberal reforms occur in the context of financial and political crisis of the State that lacks the resources to efficiently manage infrastructures such as irrigation systems. This kind of institutional and economic reforms risk accelerating processes of social and economic marginalisation, including landlessness, in particular for poor rural women that mainly use irrigated land for subsistence production. The study combines an analysis of the historical and geographical context with the study of relevant literature and original fieldwork. Fieldwork was conducted between February and June 2007 (where I mainly collected secondary data, maps and statistics and conducted preliminary visit to Chókwè) and from October 2007 to March 2008. Fieldwork methodology was qualitative and used semi-structured interviews with central and local Government officials, technical experts of the irrigation scheme, civil society organisations, international NGOs, rural extensionists, and water users from the irrigation scheme, in particular those women smallfarmers members of local farmers’ associations. Thanks to the collaboration with the Union of Farmers’ Associations of Chókwè, she has been able to participate to members’ meeting, to education and training activities addressed to women farmers members of the Union and to organize a group discussion. In Chókwè irrigation scheme, women account for the 32% of water users of the familiar sector (comprising plot-holders with less than 5 hectares of land) and for just 5% of the private sector. If one considers farmers’ associations of the familiar sector (a legacy of Frelimo’s cooperatives), women are 84% of total members. However, the security given to them by the land title that they have acquired through occupation is severely endangered by the use that they make of land, that is considered as “non efficient” by the irrigation scheme authority. Due to a reduced access to marketing possibilities and to inputs, training, information and credit women, in actual fact, risk to see their right to access land and water revoked because they are not able to sustain the increasing cost of the water fee. The myth of the “efficient producer” does not take into consideration the characteristics of inequality and gender discrimination of the neo-liberal market. Expecting small-farmers, and in particular women, to be able to compete in the globalized agricultural market seems unrealistic, and can perpetuate unequal gendered access to resources such as land and water.

The Influence of Fractures on Vulnerability to Pollution of a Carbonate Aquifer: Monte Conero (Italy)

The carbonate outcrops of the anticline of Monte Conero (Italy) were studied in order to characterize the geometry of the fractures and to establish their influence on the petrophysical properties (hydraulic conductivity) and on the vulnerability to pollution. The outcrops form an analog for a fractured aquifer and belong to the Maiolica Fm. and the Scaglia Rossa Fm. The geometrical properties of fractures such as orientation, length, spacing and aperture were collected and statistically analyzed. Five types of mechanical fractures were observed: veins, joints, stylolites, breccias and faults. The types of fractures are arranged in different sets and geometric assemblages which form fracture networks. In addition, the fractures were analyzed at the microscale using thin sections. The fracture age-relationships resulted similar to those observed at the outcrop scale, indicating that at least three geological episodes have occurred in Monte Conero. A conceptual model for fault development was based on the observations of veins and stylolites. The fracture sets were modelled by the code FracSim3D to generate fracture network models. The permeability of a breccia zone was estimated at microscale by and point counting and binary image methods, whereas at the outcrop scale with Oda’s method. Microstructure analysis revealed that only faults and breccias are potential pathways for fluid flow since all veins observed are filled with calcite. According this, three scenarios were designed to asses the vulnerability to pollution of the analogue aquifer: the first scenario considers the Monte Conero without fractures, second scenario with all observed systematic fractures and the third scenario with open veins, joints and faults/breccias. The fractures influence the carbonate aquifer by increasing its porosity and hydraulic conductivity. The vulnerability to pollution depends also on the presence of karst zones, detric zones and the material of the vadose zone.

Access to specialized pediatric cancer care in Switzerland

Specialized pediatric cancer centers (PCCs) are thought to be essential to obtain state-of-the-art care for children and adolescents. We determined the proportion of childhood cancer patients not treated in a PCC, and described their characteristics and place of treatment.