This study investigated the effectiveness of polymerization of various curing regimes on five nanocomposite restorative materials-Z350, Grandio, Clearfil Majesty Esthetic, Ice and Tetric EvoCeram-by utilizing microhardness measurements. Five (n=5) disc-shaped specimens of each material were subjected to one of three curing regimes: curing with a halogen light for 20 seconds, curing with an LED light for 20 seconds and curing with an LED light for 10 seconds. Immediately following curing, hardness measurements were made with a Vickers indenter at

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Sharpshooter leafhoppers (Hemiptera: Cicadellidae: Cicadellinae) are important vectors of the plant pathogenic bacterium Xylella fastidiosa Wells et al. (Xanthomonadales: Xanthomonadaceae). This pathogen causes economically significant diseases in olive, citrus, and grapes on multiple continents. Bacterial acquisition and inoculation mechanisms are linked to X. fastidiosa biofilm formation and fluid dynamics in the functional foregut of sharpshooters, which together result in egestion (expulsion) of fluids likely carrying bacteria. One key X. fastidiosa vector is the blue–green sharpshooter, Graphocephala atropunctata (Signoret, 1854). Herein, a 3D model of the blue–green sharpshooter functional foregut is derived from a meta-analysis of published microscopy images. The model is used to illustrate preexisting and newly defined anatomical terminology that is relevant for investigating fluid dynamics in the functional foregut of sharpshooters. The vivid 3D illustrations herein and supplementary interactive 3D figures are suitable resources for multidisciplinary researchers who may be unfamiliar with insect anatomy. The 3D model can also be used in future fluid dynamic simulations to better understand acquisition, retention, and inoculation of X. fastidiosa. Improved understanding of these processes could lead to new targets for preventing diseases caused by X. fastidiosa.

Xylella fastidiosa is a multi-continental, lethal, plant pathogenic bacterium that is transmitted by sharpshooter leafhoppers (Insecta: Hemiptera: Cicadellidae: Cicadellinae) and adult spittlebugs (Hemiptera: Aphrophoridae). The bacterium forms biofilms in plant xylem and the functional foregut of the insect. These biofilms serve as sources of inoculum for insect acquisition and subsequent inoculation to a healthy plant. In this study, 3D fluid dynamic simulations were performed for bidirectional cibarial propulsion of xylem sap through tube-like grapevine xylem and an anatomically accurate model of the functional foregut of the blue-green sharpshooter, Graphocephala atropunctata. The analysis supports a model of how fluid dynamics influence X. fastidiosa transmission. The model supports the hypothesis that X. fastidiosa inoculation is mostly driven by detachment of bacteria from the foregut due to high-velocity flow during egestion (outward fluid flow from the stylets). Acquisition occurs by fluid dynamics during both egestion and ingestion (fluid uptake through the stylets and swallowing). These simulation results are supported by previously reported X. fastidiosa colonization patterns in the functional foregut and sharpshooter stylet probing behaviors. The model indicates that xylem vessel diameter influences drag forces imposed on xylem wall-adherent bacteria; thus, vessel diameter may be an important component of the complex transmission process. Results from this study are directly applicable to development of novel grapevine resistance traits via electropenetrographic monitoring of vector acquisition and inoculation behaviors.

Technical Vocational Education and Training (TVET) serves as a pillar for economic stability globally. Entrepreneurship education provides young people with essential skills that can be used in a positive manner, thus enabling them to be employers rather than employees. Marrying TVET and entrepreneurship education can help Trinidad and Tobago (T&T) in tremendous ways. These two subjects TVET and entrepreneurship can lift T&T to global prestige. Given this context, the study explored the benefits of exposing Post-Secondary TVET students to entrepreneurial training. An investigation was carried out using a mix-methods approach. The use of regression analysis and Spearman’s Correlation Analysis were used that determine the relationship between exposing Post-Secondary Technical Vocational Education and Training Students (PSTVETS) to entrepreneurship education and their interest in entrepreneurial training. Additionally, qualitative data was incorporated by utilising content analysis, focus groups and semi-structured interviews. The data revealed there was an absence of entrepreneurship education. Upon further investigation there was no real entrepreneurship culture or framework implemented within the PS schools. The results also showed the more students are exposed to entrepreneurship education more they are inclined to pursue entrepreneurship endeavours. Data also allowed the reader to grasped copious challenges experienced within TVET in T&T, that impacts on entrepreneurial training within post-secondary institutions in T&T. The researchers put forward an entrepreneurship education model that can be incorporated in the training of post-secondary schools. Additionally a strategy was articulated as to how entrepreneurship education can be adopted within the training of post-secondary institutions. Providing an adequate framework for entrepreneurial training within entrepreneurship education, and TVET provides originality and contribution to the field of TVET and entrepreneurship education.

Aim: This study determined whether prior brushing with desensitizing toothpastes (Sensodyne Rapid Relief and Colgate Pro-Relief) affected the shear bond strengths of composite to dentine surfaces after appropriate use of two different dentine bonding agents (SingleBond and PQ-1). Materials and Methods: Sixty caries free molar teeth were cleaned, disinfected and embedded in individual cylinders of polymethylmethracyrlate. The occulsal surfaces were flattened to expose dentine and finished down with 600 grit silicone carbide paper. The teeth were randomly divided into six groups of 10 teeth each. Two groups served as control where dentine surfaces were brushed with pumice slurry. Of the remaining 4 groups, 2 groups were brushed with Sensodyne Rapid Relief and 2 groups brushed with Colgate Pro-Relief. The dentine surfaces were brushed to simulate 2 weeks of twice-daily toothpaste use. The specimens in each of the control groups and experimental groups were subjected to dentine bonding procedures (Single Bond or PQ-1), and application of hybrid composite resin (Z-250) according to the manufacturer's instructions. A universal material testing machine, with a cross head speed of 0.05 mm/min was used to determine shear bond strengths. Results: Mean shear bond strengths ranged from 5.71 MPa (Colgate pretreatment, composite bonded with Single Bond) to 9.07 MPa (Sensodyne pretreatment, com-* Corresponding author. S. Marchan et al. 122posite bonded with Single Bond). Results showed neither of the main effects, of toothpaste type or bonding agent were significant (p > 0.05) but their interaction was (F = 4.25, p = 0.02). Post hoc analysis showed that teeth brushed with the Sensodyne group, treated with the unfilled dentine bonding agent had a significantly higher bond strength than those treated with the filled dentine bonding agent. Conclusion: The desensitizing toothpastes that use the mechanism of occlusion of open dentinal tubules in the preliminary management of tooth sensitivity should not have an adverse effect on future restorative treatment modalities.

The paper focused on the challenges impacting Technical Vocational Education and Training (TVET) within Trinidad and Tobago (T&T). The study highlighted issues plaguing TVET, with insights emanated from stakeholders within TVET institutions. The challenges that presented itself showed TVET in T&T faces copious amount of problems. Stigma, Attrition, and Quality teaching were some of the key problems affecting TVET in T&T. The researcher utilised a qualitative approach to gather data from stakeholders within the institutions. The data was put forward by way of a thematic analysis approach. Focus groups and interviews were used to extract many details that gave the study deep and rich insights on TVET and the challenges emanating at present. Two main themes emerged from the data: challenges and resources. These two areas were further broken down into sub themes. The study also showed that TVET institutions are incapable of treating with some of the issues they faced, and it requires intervention from the central government to address the macro problems that plagued TVET. The research focused on four TVET institutions that are tertiary level institutions of learning. Additionally, the study showed very persuasively that TVET is experiencing a number of significant challenges in T&T. The issues that face the institutions are very complex and which they may not be able to address in a significant way. These challenges require intervention from the governmental level, these matters require the right and adequate leadership as a very important factor in moving TVET forward.

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