Developments of electrochemistry in Environmental Technology

This thesis was submitted for the degree of Doctor of Philosophy and awarded by Brunel University.Uses of electrochemical systems in environmental control technology are described for the removal and separation of metals from solution and the destruction of dye molecules in effluents. A novel concentrator cell system for the removal of lead and cadmium from solution is developed. The operation of this system permits the pH-independent recovery of metals from solution by electrodeposition. The formation of complexes with suitable ligands is exploited to achieve the separation of metals by electrochemical methods. The separations of tin, lead and indium from each other, the separation of nickel from cobalt and the separation of copper and palladium from cobalt are used to illustrate the benefits of complex formation. A three-compartment electrodialysis cell for removal of nickel from cobalt exploiting the greater stability of the nickel-EDTA complex compared with the Co-EDTA complex is described. Efficient removal of nickel from cobalt can be achieved but there is a compromise between cobalt purity and the percentage of cobalt transferred to the catholyte chamber for recovery. The anodic oxidation of a number of dye molecules including methylene blue, acid blue 25, reactive blue 2 and reactive blue 15 in chloride solution has been studied. The anodic oxidation of methylene blue results in the formation of seven neutral and two charged intermediates. The main intermediate is identified by X-ray diffraction crystal structure determination and accurate mass spectrometry as the novel compound 4,6-dichloro-7-dimethylamino-3H-phenothiazin-3 -one, (C14HjoCI2N20S) formed by replacement of one of the diirnethylamino groups of methylene blue with oxygen accompanied by regiospecific chlorination of the carbocylic system. The mass spectra of other intermediates formed are interpreted in terms of this structure. An electroadsorption system combining adsorption and electrolytic processes to achieve the elimination of the chlorinated compounds that are formed during the electro-oxidation of methylene blue is also reported.Financial support obtained from Aleppo University

The role of telomeres in pulmonary fibrosis and its effects on choices of treatment

Idiopathic pulmonary fibrosis (IPF) is an aggressive disease with no known origin. Scar tissue continues to build up in the lungs diminishing pulmonary function. Without successful treatment, patients with IPF have a mean survival of 5 years after diagnosis. Though the exact etiology of IPF is unknown, studies have established a role of telomeres in 25% or more of familial or sporadic cases. Mutations in the genes that encode for the components of telomerase have been implicated as the cause of the telomere dysfunction seen in these cases. The mutations examined below include TERT, TERC, RTEL1, TINF2, and PARN. With this link in mind, the available and the researched treatment plans are discussed. Of the discussed therapies, the researched treatment options that target the telomere-specific cases of IPF are a synthetic sex hormone (danazol), stem cell therapy, and a small molecule activator (GRN510). The remaining treatment plans discussed target either the direct cause of symptoms or the symptoms themselves. These studied options include N-acetylcysteine, prednisone, azathioprine, pirfenidone, nintedanib (with and without statins), and low-dose inhaled carbon monoxide. The treatment options with the favored positive results are danazol and nintedanib

A (törvényes) vád problematikája egy jogeset tükrében

By reviewing the case law, the author outlines possible developments in the field of prosecution with regard to the current and the proposed codification of the new Hungarian Criminal Procedure Code.A szerző az ítélkezési gyakorlat áttekintésével felvázolja az esetleges fejleményeket a vádemelés terén a hatályos és az új magyar büntetőeljárási törvénykönyv kodifikációs javaslata tekintetében

Lysosomal storage, impaired autophagy and innate immunity in Gaucher and Parkinson's diseases: insights for drug discovery

Impairment of autophagic–lysosomal pathways is increasingly being implicated in Parkinson's disease (PD). GBA1 mutations cause the lysosomal storage disorder Gaucher disease (GD) and are the commonest known genetic risk factor for PD. GBA1 mutations have been shown to cause autophagic–lysosomal impairment. Defective autophagic degradation of unwanted cellular constituents is associated with several pathologies, including loss of normal protein homeostasis, particularly of α-synuclein, and innate immune dysfunction. The latter is observed both peripherally and centrally in PD and GD. Here, we will discuss the mechanistic links between autophagy and immune dysregulation, and the possible role of these pathologies in communication between the gut and brain in these disorders. Recent work in a fly model of neuronopathic GD (nGD) revealed intestinal autophagic defects leading to gastrointestinal dysfunction and immune activation. Rapamycin treatment partially reversed the autophagic block and reduced immune activity, in association with increased survival and improved locomotor performance. Alterations in the gut microbiome are a critical driver of neuroinflammation, and studies have revealed that eradication of the microbiome in nGD fly and mouse models of PD ameliorate brain inflammation. Following these observations, lysosomal–autophagic pathways, innate immune signalling and microbiome dysbiosis are discussed as potential therapeutic targets in PD and GD. This article is part of a discussion meeting issue ‘Understanding the endo-lysosomal network in neurodegeneration’

Taper Preparation Variability Compared to Current Taper Standards Using Computed Tomography

Introduction. The purpose of this study was to compare the taper variation in root canal preparations among Twisted Files and PathFiles-ProTaper .08 tapered rotary files to current standards. Methods. 60 root canals with severe angle of curvature (between 25° and 35°) and short radius (r < 10 mm) were selected. The canals were divided randomly into two groups of 30 each. After preparation with Twisted Files and PathFiles-ProTaper to size 25 taper .08, the diameter was measured using computed tomography (CT) at 1, 3, and 16 mm. Canal taper preparation was calculated at the apical third and at the middle-cervical third. Results. Of the 2 file systems, both fell within the ±.05 taper variability. All preparations demonstrated variability when compared to the nominal taper .08. In the apical third, mean taper was significantly different between TF and PathFiles-ProTaper (P value < 0.0001; independent t-test). Mean Taper was significantly higher with PathFile-ProTaper. In the middle-cervical third, mean Taper was significantly higher with TF (P value = 0.015; independent t-test). Conclusion. Taper preparations of the investigated size 25 taper .08 were favorable but different from the nominal taper

Rheological Behavior of a New Amorphous Alloy (Al74Cu16Mg10)99,7Zr0.3

A new amorphous alloy (Al74Cu16Mg10)99,7Zr0.3 was prepared the applying a melt-spinning technique. Temperature dependence of viscosity of the alloy was determined using data from a PerkinElmer TMS2 thermo-mechanical analyzer processed according to a methodology based on the Free Volume Model (FVM). The strength of the alloy was calculated according to the Yang equation and the glass-forming ability was calculated according to the values of the Angell index mA. The activation energy of crystallization and the activation energy of the glass transition were computed using data from differential scanning calorimetry and thermomechanical experiments respectively. The activation energy of crystallization Еx = 168 ± 3.7 kJ/mol, was found to be higher than the activation energy of the glass transition Еg = 156 ± 1.4 kJ/mol, which means a dominant contribution of the atomic transport barrier, compared to the nucleation barrier. The relatively high temperature interval of the supercooled melt state Tx-Tg = 32 K and the low viscosity values in the same range ƞ(Тg) = 3.40E + 11 Pa.s and ƞ(Тx) = 1.87E + 10 Pa.s would allow thermomechanical treatment of the alloy in the temperature range of supercooled melt

Various heat-treated nickel–titanium rotary instruments evaluated in S-shaped simulated resin canals

AbstractBackground/purposeHeat treatment of nickel–titanium (NiTi) alloy produces a better arrangement of the crystal structure, thereby leading to increased flexibility and improved fatigue resistance or plastic behavior. This study aimed to assess the performance of various heat-treated NiTi rotary instruments in S-shaped resin canals.Materials and methodsForty S-shaped resin canals were instrumented (10/group) with either Twisted Files (R-phase), WaveOne (M-wire), Hyflex CM, or V Taper 2H (CM-wire) with the same apical size and taper (25/0.08). Each S-shaped resin canal was scanned both before and after instrumentation with microcomputed tomography. Changes in canal volume and transportation were evaluated at regular intervals (0.5 mm). Differences between instruments at the apical curve, coronal curve, and straight portion of the canals were analyzed statistically.ResultsAll tested instruments caused more transportation at the coronal rather than apical curvatures, with the exception of Twisted Files for which apical transportation was the highest for any instrument or location (P<0.05). The transportation was mostly influenced by the alloy type rather than their cross-sectional characteristics (P<0.05). The volumetric increase after instrumentation was similar for all tested instruments at the apical curve (P>0.05), whereas Hyflex CM created the most conservative preparations at the coronal curve (P<0.05). At the straight portion, volumetric changes were largest for Twisted Files and smallest for V Taper 2H (P<0.05).ConclusionAmongst heat-treated NiTi instruments, the CM-wire based instruments created the most favorable preparations in S-shaped resin canals

Shaping ability of BioRace, ProTaper NEXT and Genius nickel-titanium instruments in curved canals of mandibular molars: a MicroCT study

Aim To evaluate and compare the canal shaping ability of BioRace, ProTaper NEXT and Genius engine‐driven nickel‐titanium (NiTi) file systems in extracted mandibular first molars using micro‐computed tomography (MCT). Methodology Sixty mesial root canals of mandibular first molars were randomly divided into three equal groups, according to the instrument system used for root canal preparation (n = 20): BioRace (BR), ProTaper NEXT (PTN) or Genius (GN). Root canals were prepared to the full WL using a crown‐down technique up to size 35, .04 taper instruments for BR and GN groups and size 30, .07 taper instruments for the PTN group. MCT was used to scan the specimens before and after canal instrumentation. Changes in dentine volume, the percentage of uninstrumented canal surface and degree of canal transportation were evaluated in the coronal, middle and apical thirds of canals. Data were analysed statistically using one‐way analysis of variance and Tuckey's post hoc tests with the significance level set at 5%. Results There were no significant differences between the three groups in the terms of dentine removed after preparation and determination of the root canal volume, or percentage of uninstrumented canal surface (P > 0.05). No significant differences were found between the systems for canal transportation in any canal third (P > 0.05). Conclusions The shaping ability of the BR, PTN and GN NiTi file systems was equally effective. All instrumentation systems prepared curved root canal systems with no evidence of undesirable changes in 3D parameters or significant shaping errors

Computed micro-tomographic evaluation of glide pathwith nickel-titanium rotary pathFile in maxillary firstmolars curved canals

Introduction: X-ray computed micro-tomography scanning allows high-resolution 3-dimensional imaging of small objects. In this study, micro-CT scanning was used to compare the ability of manual and mechanical glide path to maintain the original root canal anatomy. Methods: Eight extracted upper first permanent molars were scanned at the TOMOLAB station at ELETTRA Synchrotron Light Laboratory in Trieste, Italy, with a microfocus cone-beam geometry system. A total of 2,400 projections on 360 degrees have been acquired at 100 kV and 80 mu A, with a focal spot size of 8 mu m. Buccal root canals of each specimen (n = 16) were randomly assigned to Path File (P) or stainless-steel K-file (K) to perform glide path at the full working length. Specimens were then microscanned at the apical level (A) and at the point of the maximum curvature level (C) for post-treatment analyses. Curvatures of root canals were classified as moderate (<= 35 degrees) or severe (>= 40 degrees). The ratio of diameter ratios (RDRs) and the ratio of cross-sectional areas (RAs) were assessed. For each level of analysis (A and C), 2 balanced 2-way factorial analyses of variance (P < .05) were performed to evaluate the significance of the instrument factor and of canal curvature factor as well as the interactions of the factors both with RDRs and RAs. Results: Specimens in the K group had a mean curvature of 35.4 degrees +/- 11.5 degrees; those in the P group had a curvature of 38 degrees +/- 9.9 degrees. The instrument factor (P and K) was extremely significant (P < .001) for both the RDR and RA parameters, regardless of the point of analysis. Conclusions: Micro-CT scanning confirmed that NiTi rotary Path File instruments preserve the original canal anatomy and cause less canal aberrations. (J Endod 2012;38:389-393