Horizon of quantum black holes in various dimensions

We adapt the horizon wave-function formalism to describe massive static spherically symmetric sources in a general $(1+D)$-dimensional space-time, for $D>3$ and including the $D=1$ case. We find that the probability $P_{\rm BH}$ that such objects are (quantum) black holes behaves similarly to the probability in the $(3+1)$ framework for $D> 3$. In fact, for $D\ge 3$, the probability increases towards unity as the mass grows above the relevant $D$-dimensional Planck scale $m_D$. At fixed mass, however, $P_{\rm BH}$ decreases with increasing $D$, so that a particle with mass $m\simeq m_D$ has just about $10\%$ probability to be a black hole in $D=5$, and smaller for larger $D$. This result has a potentially strong impact on estimates of black hole production in colliders. In contrast, for $D=1$, we find the probability is comparably larger for smaller masses, but $P_{\rm BH} < 0.5$, suggesting that such lower dimensional black holes are purely quantum and not classical objects. This result is consistent with recent observations that sub-Planckian black holes are governed by an effective two-dimensional gravitation theory. Lastly, we derive Generalised Uncertainty Principle relations for the black holes under consideration, and find a minimum length corresponding to a characteristic energy scale of the order of the fundamental gravitational mass $m_D$ in $D>3$. For $D=1$ we instead find the uncertainty due to the horizon fluctuations has the same form as the usual Heisenberg contribution, and therefore no fundamental scale exists.Comment: Latex, 16 pages, 8 figures. Final version to appear in PL

Early wound healing score (EHS): an intra- and inter-examiner reliability study

The early wound healing score (EHS) was introduced to assess early wound healing of periodontal soft tissues after surgical incision. The purpose of this study is to evaluate the intra- and inter-examiner reliability of the EHS. Six examiners with different levels of training and clinical focus were enrolled. Each examiner was trained on the use of the EHS before starting the study. Thereafter, 63 photographs of three different types of surgical incisions taken at day 1, 3 or 7 post-operatively were independently evaluated according to the proposed assessment method. A two-way random intra-class correlation coefficient (ICC) and 95% confidence interval (CI) were used to analyze the intra- and inter-examiner reliability for the EHS. The inter-examiner reliability for the EHS was 0.828 (95% CI: 0.767-0.881). The intra-examiner reliability ranged between 0.826 (95% CI: 0.728-0.891) and 0.915 (95% CI: 0.856-0.950). The results therefore show an "almost perfect agreement" for intra- and inter-examiner reliability. The EHS provides a system for reproducible repeated ratings for the early healing assessment of incisions of periodontal soft tissues. Even when used by examiners with different clinical experience and specialty, it shows a high correlation coefficient

Microleakage At The Composite-repair Interface: Effect Of Different Adhesive Systems.

The purpose of the present study was to evaluate the microleakage at the composite-repair interface using different bonding systems. Composite resin specimens (Filtek Z250 - 3M-ESPE) were divided into five groups (n=20) according to the following bonding mechanism: C - control - etching with 35% phosphoric acid; SB1 - etching and application of one coat of Single Bond (3M-ESPE); SB2 - etching and application of two coats of Single Bond (3M-ESPE); SMP1 - etching, application of Scotchbond Multi-Purpose primer (3M-ESPE) followed by the adhesive and, SMP2 - etching, application of Scotchbond Multi-Purpose adhesive (3M-ESPE) without the primer. Thereafter, all groups received new resin application. Samples were thermocycled (500 cycles / 5ºC - 55ºC [±2]) and immersed for 4h in 2% methylene blue buffered dye solution (7.0 pH). Three examiners measured the extent of microleakage in a stereoscope microscope, using four representative scores. For all experimental groups, no significant difference in microleakage at the repair was identified by Kruskal-Wallis test (p > 0.05). Therefore, different types of bonding systems presented the same effect on the dye penetration along the repair interface.12219-2

Statistical results on restorative dentistry experiments: effect of the interaction between main variables

Statistical analysis interpretation is a critical field in scientifc research. When there is more than one main variable being studied in a research, the effect of the interaction between those variables is fundamental on experiments discussion. However, some doubts can occur when the p-value of the interaction is greater than the signifcance level. OBJECTIVE: To determine the most adequate interpretation for factorial experiments with p-values of the interaction nearly higher than the signifcance level. MATERIALS AND METHODS: The p-values of the interactions found in two restorative dentistry experiments (0.053 and 0.068) were interpreted in two distinct ways: considering the interaction as not signifcant and as signifcant. RESULTS: Different findings were observed between the two analyses, and studies results became more coherent when the signifcant interaction was used. CONCLUSION: The p-value of the interaction between main variables must be analyzed with caution because it can change the outcomes of research studies. Researchers are strongly advised to interpret carefully the results of their statistical analysis in order to discuss the findings of their experiments properly

Microinfiltração na interface compósito-reparo: efeito de diferentes sistemas adesivos

The purpose of the present study was to evaluate the microleakage at the composite-repair interface using different bonding systems. Composite resin specimens (Filtek Z250 - 3M-ESPE) were divided into five groups (n=20) according to the following bonding mechanism: C - control - etching with 35% phosphoric acid; SB1 - etching and application of one coat of Single Bond (3M-ESPE); SB2 - etching and application of two coats of Single Bond (3M-ESPE); SMP1 - etching, application of Scotchbond Multi-Purpose primer (3M-ESPE) followed by the adhesive and, SMP2 - etching, application of Scotchbond Multi-Purpose adhesive (3M-ESPE) without the primer. Thereafter, all groups received new resin application. Samples were thermocycled (500 cycles / 5&ordm;C - 55&ordm;C [&plusmn;2]) and immersed for 4h in 2% methylene blue buffered dye solution (7.0 pH). Three examiners measured the extent of microleakage in a stereoscope microscope, using four representative scores. For all experimental groups, no significant difference in microleakage at the repair was identified by Kruskal-Wallis test (p >; 0.05). Therefore, different types of bonding systems presented the same effect on the dye penetration along the repair interface.O objetivo do presente estudo foi avaliar o efeito de diferentes sistemas adesivos sobre a microinfiltração na interface de reparos em resina composta. Corpos-de-prova do compósito Filtek Z250 (3M-ESPE) foram divididos aleatoriamente em cinco grupos (n=20) de acordo com a forma de confecção do reparo: C - controle - condicionamento com ácido fosfórico a 35%; SB1 - condicionamento ácido e aplicação de uma camada do agente de união Single Bond (3M-ESPE); SB2 - condicionamento ácido e aplicação de duas camadas de Single Bond; SMP1 - condicionamento ácido, aplicação do primer e do adesivo do sistema Scotchbond Multipurpose Plus (3M-ESPE) e SMP2 - condicionamento ácido e aplicação apenas do adesivo do ultimo sistema. O reparo foi finalizado com a inserção de nova camada do compósito restaurador. As amostras foram termocicladas (500 ciclos / 5-55&deg;C [&plusmn;2]) e imersas por 4h em solução tamponada de azul de metileno 2% (pH 7,0). A penetração do corante na interface do reparo foi avaliada em lupa estereoscópica (40x) por três examinadores utilizando quatro escores representativos. A análise estatística não encontrou diferenças entre os grupos experimentais (Kruskal-Wallis / p >; 0.05). Dessa maneira, os diferentes sistemas adesivos mostraram comportamento semelhante sobre a microinfiltração na interface do reparo

O mal-estar do coletivo: uma análise sobre as liberdades individuais dentro de uma ecovila

Este trabalho visa analisar como as liberdades individuais são expressas em uma proposta de convivência voltada para o coletivo, como são as ecovilas. O presente estudo contribui para uma reflexão sobre a vida em comunidade, assim como para criar um debate sobre trocas e concessões possíveis entre indivíduo e sociedade. A partir de uma pesquisa de campo, de abordagem qualitativa (com observação participante e entrevistas), foi possível perceber que os conflitos fazem parte do cotidiano local, mas que a convivência se torna viável através de construções de estratégias e propósitos – que podem ser importantes para a elaboração de alternativas à sociedade atual. Percebemos que os desafios para se construir uma vida com senso de comunidade em uma ecovila são diários, e são observados por seus moradores de diferentes formas – ao mesmo tempo em que estes ainda estão buscando conjugar as liberdades individuais com as necessidades coletivas, em um processo contínuo

Characteristics of the bonding to yttrium-stabilized tetragonal zirconia polycrystal ceramics

Orientadores: Giselle Maria Marchi Baron, Marcelo GianniniTese (doutorado) - Universidade Estadual de Campinas, Faculdade de Odontologia de PiracicabaResumo: Cerâmicas de zircônia tetragonal policristalina contendo ítrio (Y-TZP) apresentam propriedades mecânicas superiores as das demais cerâmicas odontológicas. No entanto, a técnica de cimentação mais adequada a estes materiais ainda não foi determinada. Os objetivos deste estudo foram: 1) Revisar a literatura a respeito de cerâmicas Y-TZP e seu uso em odontologia; 2) Avaliar o efeito de diferentes intensidades de energia do laser de Er:YAG e do jateamento com partículas de Al2O3 na rugosidade superficial e nas características morfológicas de cerâmicas Y-TZP e 3) Investigar a influência de diferentes tratamentos de superfície e primers para metal na resistência de união de dois cimentos resinosos a cerâmica Y-TZP. A análise da rugosidade superficial e das características morfológicas foi realizada em duas cerâmicas Y-TZP: Cercon Smart Ceramics e Procera Zirconia. Trinta placas de cada cerâmica foram separadas em cinco grupos experimentais de acordo com o tratamento de superfície recebido [nenhum tratamento (Controle), jateamento com partículas de Al2O3 ou irradiação com laser de Er:YAG em diferentes intensidades de energia (200mJ, 400mJ ou 600mJ)]. Após o respectivo tratamento superficial, as placas foram cobertas com ouro e a rugosidade superficial média (Ra, mm) foi mensurada em microscopia confocal. Características morfológicas das superfícies foramobservadas em microscopia óptica e eletrônica de varredura. Os resultados demonstraram que a irradiação com laser nas intensidades de 400mJ e 600mJ promoveu aumento acentuado da rugosidade superficial, além da formação de fendas, perda de massa e alteração de cor. A irradiação com 200mJ de intensidade e o jateamento com partículas de Al2O3 resultaram em alterações superficiais menos agressivas que as altas intensidades do laser. Para a análise da resistência de união, 240 placas de cerâmica (Cercon SmartCeramics) e 240 fragmentos de dentina com extremidade recortada em formato cilíndrico (0,8mm de diâmetro) foram distribuídos em 24 grupos (n=10) de acordo com a combinação entre tratamento de superfície (nenhum, jateamento com partículas de Al2O3 ou irradiação com laser de Er:YAG utilizando 200mJ como intensidade de energia), primer para metal (nenhum, Alloy Primer, Metal Primer II ou Metaltite) e cimento resinoso (Panavia F2.0 ou Calibra). Fragmentos de dentina foram cimentados nas placas de cerâmica, os corpos- eprova foram fixados ao aparato de microcisalhamento e o ensaio foi realizado com velocidade de 1mm/min até a fratura. O jateamento com partículas de Al2O3 resultou em maior resistência de união para ambos os cimentos resinosos. Comparado ao Panavia F2.0, o cimento Calibra apresentou maior resistência de união nos grupos jateados e irradiados. Os dois cimentos demonstraram comportamento semelhante nos grupos sem tratamento de superfície. Os três primers para metal apresentaram resultados semelhantes entre si, independentemente do tratamento da superfície e do cimento resinoso, e a resistência de união da interface cerâmica-dente aumentou com a sua utilização. Pode-se concluir que, apesar da irradiação com 200mJ de intensidade promover alterações superficiais na cerâmica Y-TZP, apenas associação do jateamento com partículas de Al2O3 com a aplicação de primers para metal constitui numa técnica efetiva para união de cimentos resinosos a estas cerâmicasAbstract: Yttrium-stabilized tetragonal zirconia polycrystal (Y-TZP) ceramics present superior mechanical properties compared to other dental ceramics. However, the most adequate luting technique for these materials is unknown. The aims of this study were: 1) To review the literature regarding Y-TZP ceramics and their dental application; 2) To evaluate the effect of different energy intensities of the Er:YAG laser and of air abrasion with Al2O3 particles on the surface roughness and morphologic characteristics of Y-TZP ceramics, and 2) To investigate the influence of different surface treatments and metal primers on the bond strength of two resin cements to a Y-TZP ceramic. The surface roughness and morphologic features were tested in two Y-TZP ceramics: Cercon Smart Ceramics and Procera Zirconia. Thirty plates from each ceramic material were allocated into five groups according to the surface treatment received [none (control), air abrasion with Al2O3 particles or irradiation with Er:YAG laser with three different energy intensities (200mJ, 400mJ or 600mJ)]. After the respective surface treatment, ceramic plates were gold-coated and their mean surface roughness (Ra, mm) was measured using confocal microscopy. Morphological characteristics were examined through optical and scanning electron microscopy. Results demonstrated that irradiation with 400mJ or 600mJ increased surface roughness and created cracks, loss of mass and colour changes on ceramic surfaces. Irradiation with 200mJ and air abrasion with Al2O3 particles provide surface alterations less aggressive than the ones caused by higher intensities of the laser. For the bond strength evaluation, 240 plates of ceramic (Cercon Smart Ceramics) and 240 fragments of dentin trimmed into a cylindrical shape (0.8mm diameter) were assigned into 24 groups (n=10) according to the combination of surface treatment (none, air abrasion with Al2O3 particles, or Er:YAG laser irradiation with 200mJ of energy intensity), metal primer (None, Alloy Primer, Metal Primer II or Metaltite), and resin cement (Panavia F2.0 or Calibra). Fragments of dentin were luted to ceramic surfaces, specimens were fixed in th abrasion with Al2O3 particles resulted in increased bond strength for both resin cements. Air abraded and laser irradiated specimens presented higher bond strength with Calibra resin cement than with Panavia F2.0. Both resin cements presented similar behavior on untreated surfaces. The three metal conditioners presented similar results regardless of the surface treatment and resin cement, significantly increasing the bond strength. It could be concluded that, although irradiation with 200mJ of energy intensity promotes superficial alterations on the Y-TZP ceramic, only the association of air abrasion with Al2O3 particles and metal primers application constitutes an effective technique for bonding resin cements to Y-TZP ceramicsDoutoradoDentísticaDoutor em Clínica Odontológic

Occlusal Interferences: How Can This Concept Influence The Clinical Practice?

This brief review discusses the role of occlusal interferences on the development and progression of temporomandibular dysfunction (TMD) and postural disorders. The eligible literature is described and critically presented to demonstrate that occlusal interferences are an important factor in the risk of TMD. Several studies have demonstrated through their findings that the use of occlusal adjustments, whether or not associated with restorative procedures, might avoid the development of articular problems in vulnerable patients. The occlusal interferences caused by restorative procedures or orthodontic treatment can cause TMDs in susceptible patients, and occlusal adjustments can be an alternative in the treatment of these TMDs.4487-9

Relating Wigner's Friend scenarios to Nonclassical Causal Compatibility, Monogamy Relations, and Fine Tuning

Nonclassical causal modeling was developed in order to explain violations of Bell inequalities while adhering to relativistic causal structure and faithfulness -- that is, avoiding fine-tuned causal explanations. Recently, a no-go theorem stronger than Bell's theorem has been derived, based on extensions of Wigner's friend thought experiment: the Local Friendliness (LF) no-go theorem. We herein contend that LF no-go theorem poses formidable challenges for the field of causal modeling, even when nonclassical and/or cyclic causal explanations are considered. We first recast the LF inequalities, one of the key elements of the LF no-go theorem, as special cases of monogamy relations stemming from a statistical marginal problem; we then further recast LF inequalities as causal compatibility inequalities emerging from a nonclassical causal marginal problem. We find that the LF inequalities emerge from the causal modeling perspective even when allowing the latent causes of observed events to admit post-quantum descriptions, such as Generalised Probabilistic Theories (GPT) or even more exotic causal compatibility prescriptions. We prove that no nonclassical causal model can explain violations of LF inequalities without both rejecting various well-motivated causal-metaphysical assumptions and violating the No Fine-Tuning principle. Finally, we note that these obstacles cannot be overcome even if one were to appeal to cyclic causal models.Comment: 14+6 pages, 9 figures. Comments welcome