Invasive Cervical Root Resorption: A Comprehensive Review on Pathogenesis, Diagnosis, and Treatment

Invasive cervical root resorption (ICRR) is a dental pathology, marked by unexpected destruction originating in the cervical region of the tooth. This comprehensive literature review provides a holistic view into the pathogenesis, clinical manifestation, and precise management of ICRR, aiming to guide endodontists and enhance patient care and treatment outcomes. The review delves into the potential etiology of ICRR, covering contributing factors such as trauma, orthodontic treatment, and other pertinent conditions. It outlines the clinical and radiographic indicators, underscoring the crucial role of early detection and precise diagnosis in effectively managing and halting ICRR progression. The exploration of treatment approaches is thorough, ranging from non-surgical methods like vital pulp therapy or root canal treatment to surgical interventions. This review accentuates the essential role of interdisciplinary collaboration among diverse dental specialties in enhancing ICRR management. It highlights the importance of a consolidated strategy in enhancing treatment outcomes and preserving tooth structure and function. Moreover, it investigates prevention methods, risk evaluation, and identifies prospective research pathways to address the existing knowledge gaps

Dissociative adsorption of methane on surface oxide structures of Pd-Pt alloys

The dissociative adsorption of methane on variously oxidized Pd, Pt and Pd-Pt surfaces is investigated using density-functional theory, as a step towards understanding the combustion of methane on these materials. For Pd-Pt alloys, models of surface oxide structures are built on the basis of known oxides on Pd and Pt. The methane adsorption energy presents large variations depending on the oxide structure and composition. Adsorption is endothermic on the bare Pd(111) metal surface as well as on stable thin layer oxide structures such as the ($\sqrt{5}\times\sqrt{5}$) surface oxide on Pd(100) and the PtO$_2$-like oxide on Pt(111). Instead, large adsorption energies are obtained for the (100) surface of bulk PdO, for metastable mixed Pd$_{1-x}$Pt$_x$O$_{4/3}$ oxide layers on Pt(100), and for Pd-Pt(111) surfaces covered with one oxygen monolayer. In the latter case, we find a net thermodynamic preference for a direct conversion of methane to methanol, which remains adsorbed on the oxidized metal substrates via weak hydrogen-bond interactions

Psychometric Properties of the Persian Language Version of the System Usability Scale

Background: The System Usability Scale (SUS) is a widely used self–administered instrument for evaluating the usability of a wide range of products and services. The aims of this descriptive- methodological study were to develop and investigate the psychometric properties of the Iranian version of the SUS. Methods: The study was conducted among 202 university students from the Tabriz University of Medical Sciences, Iran. Content validity was evaluated by a panel of 10 experts. Construct validity was assessed by exploratory and confirmatory factor analyses. The internal consistency and test-retest reliability were assessed by Cronbach’s alpha and Intraclass Correlation Coefficient (ICC), respectively. Additionally the feasibility of the measure was judged by ceiling and floor effect. Results: Content validity of the short form of Iranian SUS was established. Factor analyses supported the conceptual uni-dimensionality, and thus confirmed the construct validity of the measure. The internal consistency (α =0.79) and test retest reliability (ICC = 0.96) were both approved and there was also no ceiling nor floor effect. Conclusions: The findings support the use of SUS for both practical and research settings in Iranian population

Statistical Discrimination and Affirmative Action in the Lab

We present results from laboratory experiments studying the impacts of affirmative-action policies. We induce statistical discrimination in simple labor-market interactions between rms and workers. We then introduce affirmative-action policies that vary in the size and duration of a subsidy firms receive for hiring discriminated-against workers. These different affirmative-action policies have nearly the same effect and practically eliminate discriminatory hiring practices. However, once lifted, few positive effects remain and discrimination reverts to its initial levels. One exception is lengthy affirmative-action policies, which exhibit somewhat longer-lived effects. Stickiness of beliefs, which we elicit, helps explain the evolution of these outcomes

A robust interface method for drop formation and breakup simulation at high density ratio using an extrapolated liquid velocity

AbstractA two-phase flow formulation for atomisation modelling is presented, with a Coupled Level Set/Volume Of Fluid (CLSVOF) technique adopted for interface-tracking. In order to achieve stable numerical solution at high density ratios, an extrapolated liquid velocity field is constructed and used in discretisation of the momentum equations. Solution accuracy is also improved when this field is also used in the scalar (VOF and Level Set) advection equations. A divergence-free algorithm is proposed to ensure satisfaction of the continuity condition for the extrapolated liquid velocity. The density and viscosity across the interface are treated sharply as a function of the Level Set to maintain the physical discontinuity. The developed method is shown to accurately predict drop formation in low Re liquid jets and the deformation and breakup morphology of a single droplet in uniform air flow at different Weber numbers (from 3.4 to 96). The mechanism for droplet breakup is determined based on an analysis of the simulation results. The computed Rayleigh–Taylor instability wavelength extracted from the acceleration of the simulated liquid droplet agrees well with experimental measurements and theoretical analysis, confirming that Rayleigh–Taylor instability dominates single drop breakup in the Weber number range studied. Finally, the influence of liquid viscosity on droplet breakup is numerically investigated; the critical Weber number separating deformation and breakup regimes is well predicted at different Ohnesorge numbers in comparison with the experimental data

A Resonant Based Test Methodology for Capacitive MEMs

This work presents a test method for capacitive Micro-Electro-Mechanical Systems (MEMS). A major class of MEMS sensors operate based on the principle of capacitance variation.The proposed test method in this work utilizes a resonant circuit to detect structural defects of capacitive MEMS sensors. It is shown that a small variation of MEMS capacitance due to a defect alters the resonance frequency considerably. It is also shown that the variation of the output amplitude can be observed for fault detection if an inductor with a high quality factor is employed in the test circuit. Mathematical approach is taken and verified to prove the validity of this work. The effects of structural defects such as short, broken and missing fingers of the MEMS comb-drive on the equivalent circuit models have been determined through frequency domain simulations.Simulation results and experimental measurements using an implemented MEMS comb drive indicate that the proposed method can detect common faults such as missing, broken and short fingers