Comparative efficacy of In-office and walking bleach techniques in whitening of non-vital teeth.

Objectives: This study aimed to compare the efficacy of two non vital whitening techniques, In-office and Walking Bleach, using 35% hydrogen peroxide. The primary research question was to determine which technique achieves greater tooth color improvement.

Materials And Methods: Fifty non-vital anterior teeth with discoloration were randomly assigned to either the In-office (n = 25) or Walking Bleach (n = 25) groups.

Resource recovery using enriched purple phototrophic bacteria in an outdoor flat plate photobioreactor: Suspended vs. attached growth.

Purple phototrophic bacteria (PPB) can produce single-cell protein from wastewater at high yields. Growing in a biofilm vs suspended can improve product quality and consistency. This study compares suspended and attached growths of enriched PPB cultures in an outdoor flat plate photobioreactor treating poultry-processing wastewater.

Urea hydrolysis and long-term storage of source-separated urine for reuse as fertiliser is insufficient for the removal of anthropogenic micropollutants.

Human and animal source-separated urine, stored and allowed to naturally hydrolyse (the bio-catalysed transformation of urea to ammonia and bicarbonate), has been used for millennia as a fertiliser in agriculture. In a context of growing water scarcity and climate uncertainty, source-separation of urine is facing a strong revival thanks to the emergence of cost-effective waterless collection systems. Concomitantly, urine source-separation can be used as a method for nutrient recovery and subsequent reuse.

Modelling and techno-economic assessment of (bio)electrochemical nitrogen removal and recovery from reject water at full WWTP scale.

At conventional wastewater treatment plants (WWTPs), reject waters originating from the dewatering of anaerobically digested sludge contain the highest nitrogen concentrations within the plant and thereby have potential for realising nitrogen recovery in a reusable form. At the same time, nitrogen removal from reject waters has potential to reduce the energetic and chemical demands of the WWTP due to a reduced nutrient load to the activated sludge process. In recent years, (bio)electrochemical methods have been extensively studied for nitrogen recovery from reject waters in laboratory-scale but not yet implemented in real WWTP environments, particularly due to concerns about the need for large capital investments.

Electrochemical oxidation processes for PFAS removal from contaminated water and wastewater: fundamentals, gaps and opportunities towards practical implementation.

Electrochemical oxidation (EO) is emerging as one of the most promising methods for the degradation of recalcitrant per- and poly-fluoroalkyl substances (PFASs) in water and wastewater, as these compounds cannot be effectively treated with conventional bio- or chemical approaches. This review examines the state of the art of EO for PFASs destruction, and comprehensively compares operating parameters and treatment performance indicators for both synthetic and real contaminated water and wastewater media. The evaluation shows the need to use environmentally-relevant media to properly quantify the effectiveness/efficiency of EO for PFASs treatment.

Implementation of a Sulfide-Air Fuel Cell Coupled to a Sulfate-Reducing Biocathode for Elemental Sulfur Recovery.

Bio-electrochemical systems (BES) are a flexible biotechnological platform that can be employed to treat several types of wastewaters and recover valuable products concomitantly. Sulfate-rich wastewaters usually lack an electron donor; for this reason, implementing BES to treat the sulfate and the possibility of recovering the elemental sulfur (S) offers a solution to this kind of wastewater. This study proposes a novel BES configuration that combines bio-electrochemical sulfate reduction in a biocathode with a sulfide-air fuel cell (FC) to recover S.

Selective Extraction of Medium-Chain Carboxylic Acids by Electrodialysis and Phase Separation.

Carboxylic acids obtained the microbial electrochemical conversion of waste gases containing carbon dioxide (, microbial electrosynthesis) can be used of nonrenewable building-block chemicals in the manufacture of a variety of products. When targeting valuable medium-chain carboxylic acids such as caproic acid, electricity-driven fermentations can be limited by the accumulation of fermentation products in the culturing media, often resulting in low volumetric productivities and titers due to direct toxicity or inhibition of the biocatalyst. In this study, we tested the effectiveness of a simple electrodialysis system in upconcentrating carboxylic acids from a model solution mimicking the effluent of a microbial electrochemical system producing short- and medium-chain carboxylic acids.

Anodic electro-fermentation: Empowering anaerobic production processes via anodic respiration.

In nature as well as in industrial microbiology, all microorganisms need to achieve redox balance. Their redox state and energy conservation highly depend on the availability of a terminal electron acceptor, for example oxygen in aerobic production processes. Under anaerobic conditions in the absence of an electron acceptor, redox balance is achieved via the production of reduced carbon-compounds (fermentation).

Extracellular electron transfer by Microcystis aeruginosa is solely driven by high pH.

Extracellular electron transfer (EET) by the cyanobacterium Microcystis aeruginosa was investigated. Observations indicate that EET onto an electrode poised at + 0.6 vs.

Staged electrochemical treatment guided by modelling allows for targeted recovery of metals and rare earth elements from acid mine drainage.

Acid mine drainage (AMD) is a challenge for current and legacy mining operations worldwide given its potential to severely harm ecosystems and communities if inadequately managed. Treatment costs for AMD are amongst the highest in the industrial wastewater treatment sector, with limited sustainable options available to date. This work demonstrates a novel chemical-free approach to tackle AMD, whereby staged electrochemical neutralisation is employed to treat AMD and concomitantly recover metals as precipitates.

Inflammatory markers IL-1β and RANK-L assessment after non-vital bleaching: A 3-month follow-up.

Objective: This study assessed IL-1β and RANK-L levels in vivo and color stability of non-vital teeth bleached using hydrogen (35%) and carbamide (37%) peroxides 3 months after treatment.

Materials And Methods: Fifty teeth were randomly divided into two groups(n = 25):35% hydrogen peroxide (HP) or 37% carbamide peroxide (CP). Four sessions of intracoronal walking-bleach procedure were performed.

Recovery of elemental sulfur with a novel integrated bioelectrochemical system with an electrochemical cell.

Several industrial activities produce wastewater with high sulfate content that can cause significant environmental issues. Although bioelectrochemical systems (BESs) have recently been studied for the treatment of sulfate contained in this wastewater, the recovery of elemental sulfur with BESs is still in its beginnings. This work proposes a new reactor configuration named BES-EC, consisting of the coupling of a BES with an electrochemical cell (EC), to treat this type of wastewater and recover elemental sulfur.

Microbial electrosynthesis system with dual biocathode arrangement for simultaneous acetogenesis, solventogenesis and carbon chain elongation.

A microbial electrosynthesis cell comprising two biological cathode chambers sharing the same anode compartment is used to promote the production of C2-C4 carboxylic acids and alcohols from carbon dioxide. Each cathode chamber provides ideal pH conditions to favor acetogenesis/carbon chain elongation (pH = 6.9), and solventogenesis (pH = 4.

Color Regression and Maintenance Effect of Intracoronal Whitening on the Quality of Life: RCT-A One-year Follow-up Study.

Objective:: This randomized clinical study evaluated two parameters: 1) the clinical color rebound of whitening patients' tooth discoloration using the walking bleaching technique and 2) the impact on psychological and aesthetic self-perception at the one-year follow-up of patients who underwent bleaching of nonvital teeth.

Methods And Materials:: Fifty study participants with nonvital tooth discoloration were recruited. Teeth were assigned randomly into one of two groups: 1) 35% hydrogen peroxide (n=25) and 2) 37% carbamide peroxide (n=25).

A modelling approach to assess the long-term stability of a novel microbial/electrochemical system for the treatment of acid mine drainage.

Microbial electrochemical processes have potential to remediate acid mine drainage (AMD) wastewaters which are highly acidic and rich in sulfate and heavy metals, without the need for extensive chemical dosing. In this manuscript, a novel hybrid microbial/electrochemical remediation process which uses a 3-reactor system - a precipitation vessel, an electrochemical reactor and a microbial electrochemical reactor with a sulfate-reducing biocathode - was modelled. To evaluate the long-term operability of this system, a dynamic model for the fluxes of 140 different ionic species was developed and calibrated using laboratory-scale experimental data.

Effectiveness and effect of non-vital bleaching on the quality of life of patients up to 6 months post-treatment: a randomized clinical trial.

Objectives: The aim of this study was to evaluate the esthetic perception of patients at 6 months after bleaching of non-vital teeth with 35% of hydrogen peroxide and 37% of carbamide peroxide using a walking bleach technique. We also assessed psychosocial impacts as well as the clinical effectiveness and stability of the color change.

Materials And Methods: The teeth bleaching treatment was randomly assigned to two groups according to the bleaching agent used: G1 HP = 35% of hydrogen peroxide (n = 25) and G2 CP = 37% of carbamide peroxide (n = 25).

Electroactive haloalkaliphiles exhibit exceptional tolerance to free ammonia.

Electrochemical activity in bacteria has been observed in numerous environments and conditions. However, enrichments in circumneutral freshwater media where acetate is the main electron donor seem to invariably lead to the dominance of Geobacter spp. Here we report on an electroactive bacterial consortium which was enriched on acetate as electron donor, but in a medium which reproduces hydrolysed urine (high pH, high salinity and high free ammonia).

A novel bioelectrochemical system for chemical-free permanent treatment of acid mine drainage.

The mining sector is currently under unprecedented pressure due to stringent environmental regulations. As a consequence, a permanent acid mine drainage (AMD) treatment is increasingly being regarded as a desirable target with direct benefits for the environment and the operational and economic viability of the resources sector. In this study we demonstrate that a novel bioelectrochemical system (BES) can deliver permanent treatment of acid mine drainage without chemical dosing.

Selective cathodic microbial biofilm retention allows a high current-to-sulfide efficiency in sulfate-reducing microbial electrolysis cells.

Selective microbial retention is of paramount importance for the long-term performance of cathodic sulfate reduction in microbial electrolysis cells (MECs) due to the slow growth rate of autotrophic sulfate-reducing bacteria. In this work, we investigate the biofilm retention and current-to-sulfide conversion efficiency using carbon granules (CG) or multi-wall carbon nanotubes deposited on reticulated vitreous carbon (MWCNT-RVC) as electrode materials. For ~2months, the MECs were operated at sulfate loading rates of 21 to 309gSO -S/m/d.

An iTRAQ characterisation of the role of TolC during electron transfer from Shewanella oneidensis MR-1.

Anodophilic bacteria have the ability to generate electricity in microbial fuel cells (MFCs) by extracellular electron transfer to the anode. We investigated the anode-specific responses of Shewanella oneidensis MR-1, an exoelectroactive Gammaproteobacterium, using for the first time iTRAQ and 2D-LC MS/MS driven membrane proteomics to compare protein abundances in S. oneidensis when generating power in MFCs, and growing in a continuous culture.

Marine phototrophic consortia transfer electrons to electrodes in response to reductive stress.

This work studies how extracellular electron transfer (EET) from cyanobacteria-dominated marine microbial biofilms to solid electrodes is affected by the availability of inorganic carbon (Ci). The EET was recorded chronoamperometrically in the form of electrical current by a potentiostat in two identical photo-electrochemical cells using carbon electrodes poised at a potential of +0.6 V versus standard hydrogen electrode under 12/12 h illumination/dark cycles.

Psychometric Validation of the Academic Motivation Scale in a Dental Student Sample.

The Academic Motivation Scale is one of the most frequently used instruments to assess academic motivation. It relies on the self-determination theory of human motivation. However, motivation has been understudied in dental education.

Fully reversible current driven by a dual marine photosynthetic microbial community.

The electrochemical activity of two seawater microbial consortia were investigated in three-electrode bioelectrochemical cells. Two seawater inocula - from the Sunshine Coast (SC) and Gold Coast (GC) shores of Australia - were enriched at +0.6 V vs.

Encouraging intrinsic motivation in the clinical setting: teachers' perspectives from the self-determination theory.

Introduction: Self-determination theory postulates that the three basic psychological needs of autonomy, competence and relatedness have to be satisfied for students to achieve intrinsic motivation and internalisation of autonomous self-regulation towards academic activities. Consequently, the influence of the clinical teaching environment becomes crucial when satisfying these needs, particularly when promoting or diminishing students' intrinsic motivation. The aim of this study was to describe and understand how clinical teachers encourage intrinsic motivation in undergraduate dental students based on the three basic psychological needs described by the self-determination theory.