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Wood is an important fuel for domestic heating appliances. Even if greenhouse gases emissions (CO2) are considered as neutral, its combustion is well known to be a source of fine particle matter (PM2.5). This work deals with the preparation and the fuel pretreatment before the combustion, and particularly the wood washing and the wood barking. The aim is to study the influence of the nature of the biomass and its pretreatment on the emission factors of gaseous and particulate pollutants emitted by new domestic heating devices in real use conditions. Fuel pretreatments lead to the reduction of total suspended matter (TSP) and carbon monoxide (CO) by 50%. The toxicity of polycyclic aromatic hydrocarbons (PAH) can also be reduced by 95% depending on the wood specie used., Le bois est un combustible important pour le chauffage domestique. Même s’il présente un bilan neutre en termes d’émission de gaz à effet de serre (CO2), sa combustion est reconnue pour être une source additionnelle de particules fines (PM2.5) lors des périodes hivernales. Ce travail porte sur la préparation et donc le prétraitement du combustible en amont de la combustion, particulièrement le lavage du combustible et l’écorçage. L’objectif est d’étudier l’influence de la nature de la biomasse et de son prétraitement sur les facteurs d’émission des polluants gazeux et particulaires émis par les nouveaux appareils de chauffage domestique dans des conditions réelles d’utilisation. Les prétraitements du combustible conduisent jusqu’à la réduction des particules totales en suspension (TSP) et du monoxyde de carbone (CO) de 50%. La toxicité des hydrocarbures aromatiques polycycliques (HAP) peut également être abaissée de 95% dépendant des essences de bois utilisées.

Objective The objective of this work was to evaluate effects of a dentifrice containing sodium fluoride (1150 ppm F) and the organic polyphosphate phytate (0.85% w/w of the hexa-sodium salt) on in situ remineralisation of early enamel erosive lesions and resistance to subsequent demineralisation. Materials and methods Subjects (n = 62) wore palatal appliances holding eight bovine enamel specimens with pre-formed erosive lesions. They brushed their natural teeth with the phytate test dentifrice (TD); a positive control dentifrice (PC, 1150 ppm fluoride as NaF); a reference dentifrice (RD, disodium pyrophosphate + 1100 ppm fluoride as NaF) or a negative control dentifrice (NC, fluoride-free) in a randomised, double-blind, crossover design. Specimens were removed at 2, 4 and 8 h post-brushing and exposed to an ex vivo acid challenge. Surface microhardness (Knoop) was measured at each stage. The primary efficacy variable was relative erosion resistance (RER); other variables included the surface microhardness recovery (SMHR), acid resistance ratio (ARR) and enamel fluoride uptake (EFU). Results After 4 h, the results for RER, ARR and EFU were in the order PC > TD = RD > NC with PC > TD = RD = NC for SMHR. Results at 2 and 8 h were generally consistent with the 4 h data. Mineralisation progressed over time. Dentifrices were generally well-tolerated. Conclusions In this in situ model, addition of phytate or pyrophosphate to a fluoride dentifrice inhibited the remineralising effect of fluoride. Both formulations still delivered fluoride to the enamel and inhibited demineralisation, albeit to a lesser extent than a polyphosphate-free dentifrice. Clinical relevance Addition of phytate or pyrophosphate to a fluoride dentifrice may reduce its net anti-erosive properties.

Activated carbons (ACs) from swine manure (SM), i.e. preliminary de-watered SM cake (Mc) and solid digestate (Md) were prepared by pyrolysis and water vapour activation. Demineralisation on obtained chars after carbonization was applied as well. Additionally, the adsorption capacity of demineralised ACs towards chromium in aqueous solutions was investigated and compared to non-demineralised ACs. Demineralisation caused a decrease in mineral matter content with more than 50% and affected characteristics and adsorption behaviour of these ACs. As a result, ACs with better developed porous texture were produced. Prepared ACs with reduced ash content demonstrated higher adsorption capacity toward Cr compared to non-demineralised ACs. The adsorption kinetics were investigated by applying two kinetic models, i.e. Lagergren pseudo-first order and pseudo-second order. The pseudo-second order kinetic model provided a better fit. Better fits are obtained for the Langmuir isotherm model and therefore a monolayer coverage chemisorption of the Cr(VI) on the ACs surface is suggested. FWO; BAS-IOCh bilateral research project

Nanofiltration of lactic acid whey: A process to improve the dryability and the quality of powder. 6. European Drying Conference: EuroDrying 2017

Einleitung: Der BoneXpert stellt eine neue Technik zur Bestimmung der periartikulären Demineralisation der Metakarpalknochen dar. Der Verlust der periartikulären Demineralisation ist ein etablierter Surrogatparameter für die radiologische Progression einer rheumatoiden Arthritis. Im Rahmen[zum vollständigen Text gelangen Sie über die oben angegebene URL], 44. Kongress der Deutschen Gesellschaft für Rheumatologie (DGRh); 30. Jahrestagung der Deutschen Gesellschaft für Orthopädische Rheumatologie (DGORh); 26. Jahrestagung der Gesellschaft für Kinder- und Jugendrheumatologie (GKJR)

Une déminéralisation par acidification à différents pH (6,7-6,4-6,1-5,8 et 5,5) induisait une dissociation partielle des micelles générant de nouvelles particules avec une hétérogénéité caséinique grandissante dans les suspensions. En parallèle, les stabilités des mousses faites à partir de ces mêmes suspensions étaient diminuées. Ces résultats confirment que le phosphate de calcium micellaire joue un rôle fondamental dans les différentes « structures-fonctions » des micelles de caséines[br/] Des suspensions micellaires ayant des états de minéralisation phospho-calcique diminués ont été préparées par acidification (6,7 (contrôle)-6,4-6,1-5,8 et 5,5) suivie d’une dialyse contre un ultrafiltrat de lait pour avoir une phase soluble identique. La déminéralisation des micelles de caséines en phosphate et calcium était progressive et induisait une dissociation partielle des molécules de caséines avec l’apparition de particules non ultracentrifugeables de 30 nm et de poids moléculaires compris entre 106 et 107 g/mole. La proportion de cette population petite en taille augmentait avec le degré de déminéralisation. En termes d'hydratation, de taille, de forme et de potentiel zêta, les micelles de caséines non dissociées semblaient similaires à celles d'origine. En parallèle, les capacités moussantes de ces suspensions n’étaient pas modifiées alors que leurs stabilités étaient réduites. Ces diminutions de stabilités des mousses mettent en évidence le rôle du phosphate de calcium micellaire dans les différentes structures-fonctions des micelles. La réduction phospho-calcique induisait une plus grande hétérogénéité des structures caséiniques dans les suspensions et probablement des propriétés interfaciales différentes.

Objectives: Hydroxyapatite (HA) is a calcium phosphate mineral which naturally present in teeth and comprises more than 98% of the natural human enamel. Pure HA has been incorporated in different commercial dental toothpastes and oral rinses for improved teeth remineralisation and treating dentine hypersensitivity by the occlusion of dentine tubules. The aims of the present study were to investigate the enamel remineralisation and dentine tubule occlusion properties of a new commercial nano-sized HA containing products.Methods: A new commercial nano-sized HA and fluoride containing toothpaste and comparative toothpaste formula (HA only and F- only) as well as an oral rinse formula (HA and F-) were prepared. The nano-sized hydroxyapatite used was characterised by Secondary Electron Microscopy (SEM), X-ray Diffraction (XRD) and Fourier Transform Infrared Spectroscopy (FTIR). The remineralisation study was carried out by immersing enamel blocks in toothpaste/oral rinse treatment solutions (diluted by a factor of 1:10 and 1:2 with acetic acid) for 96 hours. Fluorapatite formation was investigated by 19F MAS-NMR. The ability of the test products to occlude the dentine tubules was evaluated by a 2 minute treatment on etched dentine disks followed by SEM analysis.Results: Almost identical diffraction patterns for enamel and the nano-sized HA were obtained. The HA crystallite size was found to be 36 nm. The NMR spectra confirmed that no signs of fluoride in enamel control, demineralised enamel and specimen treated with HA only toothpaste alone. Fluorapatite formation was evident for the enamel specimens treated with HA and F- containing and F- only toothpaste. The present SEM study demonstrated that a combination of HA and F- provided superior tubule occlusion compared to the control toothpaste formula.Conclusion: The nano-sized HA and fluoride containing toothpaste showed evidence of both fluorapatite formation and dentine tubule occlusion.

The objective of this study was to optimize the extraction of chitin by acid proteolysis. The novelty of the method is based on the stabilization of pH by the balance between substrate composition and the acid solvent. This principle allows a simultaneous demineralization and deproteinization, the two main reactions associated with the purification of chitin. To evaluate the performance of this purification, the composition of the substrate and products was characterized. Different methods of quantification of chitin and proteins have been compared. As traditional assays were not satisfaying, a direct method of amino acids determination by gaz chromatography was selected to estimate the amount of protein. The estimate of chitin amount was based on indirect methods, mainly gravimetry, elemental analysis and thermogravimetric analysis (TGA). Kinetics of demineralization and deproteinization were examined to optimize the purification of chitin. Mass balances confirmed the consistency of results. The quality of chitin extracted by enzymatic or chemical techniques was compared with the degree of acetylation and depolymerization and the crystallinity index of chitin. The structure of chitin was also observed by scanning electron microscopy (SEM). Finally, compounds solubilized by enzymatic hydrolysis were identified and quantified., L’objectif de l’étude porte sur l’optimisation de l’extraction de la chitine par protéolyse acide. L’originalité du procédé repose sur la stabilisation du pH grâce à l’équilibre entre la composition du substrat et le solvant acide. Ce principe permet de réaliser simultanément la déminéralisation et la déprotéinisation, les deux principales réactions associées à la purification de la chitine. Pour évaluer les performances de cette purification, la composition du substrat et des produits est caractérisée. Différentes méthodes de quantification de la chitine et des protéines sont comparées. Contrairement aux dosages traditionnels, une méthode directe de dosage des acides aminés est sélectionnée pour estimer la quantité de protéines. L’estimation de la quantité de chitine repose sur des méthodes indirectes, principalement la gravimétrie, l’analyse élémentaire et l’analyse thermogravimétrique (ATG). Les cinétiques de déminéralisation et de déprotéinisation sont étudiées en vue d’optimiser la purification de la chitine. Les bilans massiques confirment la cohérence des résultats. Les caractéristiques physico-chimiques de la chitine obtenue par voie enzymatique, le degré d’acétylation, le degré de dépolymérisation et l’indice de cristallinité, sont comparées à la chitine obtenue par voie chimique. La structure de la chitine a également été observée par microscopie électronique à balayage (MEB). Enfin, les composés solubilisés par l’hydrolyse enzymatique sont identifiés et quantifiés.

Les micelles de caséine sont des suprastructures protéiques constituée des caséines s1, s2, et en association avec du phosphate de calcium. Leur arrangement est maintenu grâce à des interactions d’origine hydrophobe et électrostatique. Ces micelles de caséines sont hydratées, chargée négativement et ont un diamètre moyen de 200 nm. Leurs propriétés physico-chimiques évoluent en fonction des conditions physico-chimiques comme pH, température et force ionique. L’objectif de cette étude était de caractériser les nouvelles propriétés physico-chimiques de micelles de caséines partiellement déminéralisées sans modifier leur environnement. La stratégie était d’acidifier du lait cru écrémé à pH 6,4, 6,1, 5,8 et 5,5. Un contrôle à pH 6,7 était traité dans les mêmes conditions. Après acidification, les laits étaient dialysés à 4° C contre de l’ultrafiltrat de lait (pH 6,7) pour rétablir l’environnement ionique initial. Les différents échantillons étaient ensuite lyophilisés. La caractérisation physico-chimique des différentes micelles de caséine se faisait après leur remise en suspension à 9,5 % (m/m). Les analyses en calcium et phosphore totaux et soluble montraient que les micelles de caséine étaient plus déminéralisées alors que leur environnement ionique était similaire. En termes de caractéristiques micellaires et pour tous les échantillons, il était déterminé une unique population de particules de taille allant de 100 et 500 nm avec une moyenne de 180 nm. La charge de ces particules (potentiel zêta moyen) avait une valeur de -14 mV. Leur hydratation, déterminée après séchage des culots d’ultracentrifugation (100 000 g / 1 h à 20 °C), étaient de 2,7 g d’eau par g de culot. A l’opposé, des diminutions de blancheur ainsi que de quantité de matériel micellaire ultracentrifugable étaient observées en fonction du degré de déminéralisation des micelles. Ces deux résultats suggéraient une dissociation partielle de molécules de caséines pour les micelles partiellement déminéralisées. L’analyse en HPLC des échantillons totaux et des surnageants d’ultracentrifugation respectifs indiquait une augmentation de la proportion des caséines s1, s2 et une diminution des caséines et au sein de la structure micellaire avec une augmentation de leur degré de déminéralisation. Bien que les caractéristiques micellaires comme la taille, l’hydratation et la charge n’étaient pas modifiées, les structures néoformées étaient différentes en termes de compositions minérale et caséinique. Les perspectives de ce travail consisteront à évaluer quelques fonctionnalités technologiques de ces micelles partiellement déminéralisées (propriétés moussantes, gélifiantes et émulsifiantes).

Mention d'édition : 2ème édition; Demineralization

Die Hyposalivation ist oftmals assoziiert mit einer hohen Kariesaktivität, insbesondere bei Patienten, die im Kopf-Hals-Bereich bestrahlt werden. Neben dem Gebrauch von Speichelersatzmitteln zur Verbesserung der Symptome ist die tägliche Anwendung von Fluoridgel oder -zahnpasta (5000 µg F-/g) zur Kariesprävention zu empfehlen. Das Ziel dieser Studie war es, potenziell remineralisierende Effekte dieser Fluoridprodukte in Kombination mit de-/remineralisierenden Speichelersatzmitteln auf Schmelzläsionen zu untersuchen. Demineralisierte bovine Proben wurden in Mineralwasser [Kontrolle, W; Oktakalziumphosphatsättigung (SOKP): 0,8], einem demineralisierenden Speichelersatzmittel [Glandosane, G; SOKP: 0,3] oder in einem modifizierten (bezüglich SOKP) Speichelersatzmittel [Saliva natura, SN; SOKP: 1,9] für fünf Wochen gelagert (37°C). Die folgende Behandlung wurde zweimal täglich durchgeführt (n = 11 - 13/Gruppe): keine Behandlung (0), ProSchmelz Fluorid Gel (PS; Applikation für 10 min), Duraphat Zahnpasta (D; 10 sek putzen mit Zahnpasta/Lagerungslösungsslurry), Kombination von D+PS. Mineralverlustveränderungen aufgrund der Lagerung wurden mittels Mikroradiografie ausgewertet. Die Lagerung in G führte zu einer signifikanten Demineralisation (p < 0,05; gepaarter t-Test), wohingegen die zusätzliche Anwendung der Fluoridprodukte die demineralisierenden Effekte neutralisierte (p > 0,05). Die alleinige Lagerung in W ergab keine Veränderungen der Mineralwerte (p > 0,05), wohingegen in Kombination mit Fluoriden eine Remineralisation eintrat (p < 0,05). Für die alleinige Verwendung von SN konnte eine Remineralisation beobachtet werden (p < 0,05), aber die Fluoridprodukte konnten die Remineralisation nicht zusätzlich fördern. Unter den gegebenen Studienbedingungen reduzieren die Fluoridprodukte die Demineralisation von Glandosane und fördern die Remineralisation der in Wasser gelagerten Proben. Remineralisierende Effekte von Saliva natura konnten nicht durch die Fluoride gesteigert werden., Hyposalivation is often associated with high caries activity in particular in patients undergoing irradiation in the head/neck area. Besides the use of saliva substitutes to relieve the oral symptoms, daily application of fluoride gels or toothpaste (5000 µg F-/g) is recommended for caries prevention. The aim of this study was to evaluate potentially remineralising effects of these fluoride agents in combination with saliva substitutes on enamel subsurface lesions. Demineralised bovine specimens were either stored in mineral water [control, W; saturation with respect to octacalcium phosphate (SOCP): 0.8], a demineralising saliva substitute [Glandosane (G); SOCP: 0.3], or in a modified (with respect to SOCP) saliva substitute [Saliva natura (SN); SOCP: 1.9] for five weeks (37 °C). The following treatments were applied twice daily (11-13/group): no treatment (0), ProSchmelz fluoride gel (PS; 10 min application), Duraphat toothpaste (D; 10 s; brushing with toothpaste/storage solution slurry), combination of D+PS. Mineral parameters before/after storage were evaluated from microradiographs. Storage in G led to significant demineralisation (p < 0.05; paired t test), whereas additional use of the fluoride agents neutralised the demineralising effect (p > 0.05). Storage in W alone resulted in no changes in mineral parameters (p > 0.05), whereas in combination with fluorides remineralisation could be shown (p < 0.05). For SN alone, remineralisation was observed (p < 0.05), but no additional beneficial effects of fluorides were detected. Under the conditions chosen the fluoride agents reduce the demineralising effects of Glandosane and promote the remineralisation of specimens stored in water. Remineralising effects of Saliva natura could not be enhanced by the fluorides.

Die vorliegende In-vitro-Studie untersuchte in zwei Versuchsreihen den Einfluss von Lagerungsmedien auf die Demineralisation von bovinem Schmelz bzw. auf die De und -Remineralisation von humanem Schmelz; zusätzlich wurde der Substanzabtrag durch die Planpolitur der Zahnproben gemessen und als Kovariate in die statistischen Berechnungen aufgenommen. Im ersten Versuch wurden 80 Rinderzähne randomisiert auf fünf Lösungen (Kochsalzlösung 0,9 %, Formalin 10 % neutral gepuffert, Isopropylalkohol 70 %, Wasserstoffperoxid 3 %, Thymol 0,1 %) verteilt und gelagert. Frisch extrahierte Zähne dienten als Kontrollgruppe. Im zweiten Versuch wurden 320 humane Zähne auf vier Lagerungsmedien (Kochsalzlösung 0,9 %, Formalin 10 % neutral gepuffert, Wasserstoffperoxid 3 %, Thymol 0,1 %) verteilt. Kontrollgruppe waren hier die in Kochsalzlösung gelagerten Zähne. Nach einer Lagerungsphase (Versuch 1: 10 Monate und Versuch 2: von 3-8 Monaten) wurde aus jedem Zahn eine Schmelzprobe gewonnen, in Kunststoff eingebettet und plan poliert. Nach der Demineralisation (Versuch 1: 7 Tage, pH = 5,0; Versuch 2: 14 Tage pH = 5,0) in Buskes‘ Lösung wurde bei den humanen Proben ein Teil des demineralisierten Areals lackiert und die Proben zusätzlich 35 Tage einer Remineralisationslösung ausgesetzt. Die mittels Kontaktmikroradiographie gemessenen Parameter Läsionstiefe und Veränderung des Mineralgehalts wurden statistisch mit dem Allgemeinen Linearen Modell hinsichtlich des Effekts der Lagerungsmedien ausgewertet. Lediglich bei den in Wasserstoffperoxid gelagerten humanen Schmelzproben konnten signifikant geringere Läsionstiefen und signifikant geringere Mineralverluste nach Demineralisation festgestellt werden. Die übrigen Gruppen wiesen im Vergleich zur jeweiligen Kontrollgruppe keine signifikanten Unterschiede hinsichtlich Läsionstiefe und Mineralgehalt im de- und remineralisierten Bereich auf. Die Politur führte zu signifikant größerer Demineralisationstiefe und größerem Mineralverlust bei den humanen, nicht aber bei den bovinen Schmelzproben. Dieser Effekt ist sehr gering und ist vor allem wegen der ungewöhnlich hohen Probenanzahl in Versuch 2 statistisch signifikant. Die Planpolitur scheint für die De- und Remineralisation nur von untergeordneter Relevanz zu sein., This study aimed to evaluate the influence of various storage solutions on the de- and remineralisation of bovine and human enamel in vitro. Furthermore, the effect of grinding of specimens, which is considered standard for microradiographs was statistically controlled. In experiment 1, 80 cleaned bovine incisors were divided randomly into five groups and stored in five various solutions (NaCI 0.9 %; formalin 10 %; isopropylalcohol 70 %; H2O2 3 %; thymol 0.1 %). Freshly extracted bovine teeth were additionally prepared (control). In experiment 2, 320 human teeth were divided randomly into four groups and stored in four various solutions (NaCI 0.9 %; formalin 10 %; H2O2 3 %; thymol 0.1 %). Human teeth stored in NaCI 0.9 % served as control. After storage (experiment 1: 10 months, experiment 2: 3-8 months) a cylindrical enamel block was obtained from each tooth, embedded in epoxy resin and ground flat. After demineralisation (experiment 1: pH 5,0; 7 d, experiment 2: pH 5,0; 14 d) in Buskes` solution the bovine specimens were evaluated. Concerning the human specimens, parts of the demineralised area were covered with nail varnish and the specimens exposed to a remineralising solution (experiment 2: 35 d). The parameters were evaluated from microradiographs of thin sections (110 μm) by a dedicated software package (TMR 1.24). The received information (lesion depths, mineral loss) was statistically analysed by General Linear Model regarding the effect of storage solutions. Possible interference concerning grinding was statistically controlled. Nearly all groups showed not any significant differences with regard to lesion depths and mineral loss in the de- and remineralised areas when compared with the controls. Only H2O2 caused significantly lower lesion depths and a significantly less mineral loss in the demineralised areas (experiment 2). Additionally, a significant influence on lesion depth in the demineralised areas due to grinding was observed. Grinding to flatten the specimens enhanced mineral loss (experiment 2) as well. However, this effect was very small, and might have become statistically significant because of the high sample size. Furthermore, flatting of specimens has a minor relevance on de- and remineralisation.

In this study, the influence of salivary parameters and the oral microbial flora on the demineralization of tooth enamel was investigated with synchrotron tomography. In a first part four test persons wore an intraoral appliance containing enamel samples, taken from human wisdom teeth. The subjects were divided into two groups with different time periods of wearing the intraoral appliance. Afterwards the samples were analyzed with respect to a mineral loss using synchrotron tomography. In parallel, the subjects’ saliva was examined in a second part study using saliva tests. Saliva samples were analyzed to the number of S. mutans, lactobacilli, saliva buffering capacity and flow rate. Subsequently the results of both sub-studies were set in correlation using the morphological model. Group A, which wore the intraoral appliance four weeks showed no demineralization. Group B showed after six weeks different degrees of mineral loss. While one test subject in Group B showed a marked demineralization another proband showed a much higher mineral loss. Apart of the number of S. mutans the salivary parameters of the subjects varied considerably from proband to proband. In consideration of the limited sample size and specific boundary conditions (number of S. mutans equal) the morphological analysis of these findings resulted in the identification of two overdominant factors: buffer capacity and time factor. In summary, the study demonstrates the general suitability of the use of intraoral appliances, synchrotron tomography and saliva tests in order to draw conclusions about the cause-effect relationships of salivary parameters and the microbial flora.

Daudzos tehnoloģiskajos procesos ūdens kvalitāte ir atkarīga no dzelzs jonu koncentrācijas un cietības. Darbā tika pētīta elektrolīzes un elektrodialīzes procesa ietekmi uz dzelzs un kalcija jonu koncentrācijas izmaiņām un mikroorganismu attīstību ūdenī. Eksperiments tika veikts laboratorijas apstākļos, izmantojot dzelzs un kalcija jonus saturošus modeļšķīdumus. Lai raksturotu ūdens apstrādes ietekmi uz mikroorganismu vairošanās intensitātes izmaiņām, izmantoja baktērijas Pseudomonas fluorescens. Darbā tika noskaidrots, ka šķīduma elektrolīze ar tai sekojošu filtrēšanu caur kvarca smilšu slānim kopējo dzelzs jonu koncentrāciju samazina no 40 līdz 50 reizēm. Pieaugot kopējai dzelzs jonu koncentrācijai izejas šķīdumos, elektrolīzes procesā patērētais īpatnējais darbs pēc strāvas samazinās. Palielinot elektrolīzes šūnai pielikto strāvas stiprumu, kopējā dzelzs jonu koncentrācija elektrolizētajā šķīdumā samazinās, bet procesa veikšanai nepieciešamais īpatnējais darbs pieaug. Veicot CaCO3 un FeSO4 saturošu šķīdumu elekrodialīzi cirkulācijas režīmā, ir novērojama gan kalcija, gan kopējās dzelzs jonu koncentrācijas samazināšanās, pieaugot procesa laikam. Straujākas koncentrācijas izmaiņas novērojamas procesa sākumā. Realizējot šķīduma, kas satur vismaz 1mmol/L hlorīda jonus, atdzelžošanu ar elektrolīzes palīdzību, tiek ievērojami uzlabots tā mikrobioloģiskais stāvoklis. Elektrolizētajā ūdenī piecu dienu laikā nav novērojama baktērijas Pseudomonas fluorescens koloniju veidojošo vienību attīstība. Veicot ūdens elektrodialīzi, iespējams efektīvi atsāļot šķīdumu. Atsāļotajā ūdenī ievērojami samazinās (līdz pat 1500 reizēm) baktērijas Pseudomonas fluorescens koloniju veidojošo vienību attīstības intensitāte

The lecture described prevent part of MI Treatment Plan and which procedure are involved. The presenation is based on holistic approach and it is made on scientifice references.

In clinical practice early detection of dental caries enable more conservative therapy. Today new method based on laser fluorescency give us information about earliest lost of mineral from hard dental tissue. Also, caries risk tests and saliva checker as well as Tooth Mousse and newly developed MI paste can help in caries prevention and in remineralization of already demineralised hard dental tissue surface. The paste can be used for very large spectrum of diagnosis and dental gum diseases, and for sensitive prevention. Biological protection of teeth is able to achieve with glassionomers which are biocompatible, adhere on hard dental tissues and realise fluorides. The glassionomer could be used for fissure protection, root surface protection, hypersensitivity prevention, protection for immature enamel.

In the work at hand basic experimental results are presented for the mechanical/thermal dewatering (MTE, German abbreviation for ‘Mechanisch/Thermische Entwässerung’, also used for ‘mechanical/thermal expression’ in English), during which lignites or other moisture containing materials are dewatered by the combined application of heat and mechanical forces. Models are developed for the description of the kinetics during the dewatering of the different materials based on soil-mechanical fundamentals, rheology and rate-process-theory. Using mercury intrusion porosimetry (MIP), helium pycnometry, CO2 adsorption and other techniques, it is investigated, how MTE process conditions, such as temperature and pressure, affect the physical properties pore size distribution and pore diameters, specific surface area, skeletal and ‘true’ density, hardening, compressibility and shrinkage behaviour of low rank coals from Australia, Greece and Germany. The results provide a detailed insight in process kinetics and mechanism, in coal structure and structural changes during the dewatering process. Additionally re-hydration and combustibility of MTE products as well as the removal of minerals from lignites during the MTE process is investigated. Results from the mechanical/thermal dewatering and water leaching tests are compared, which prove, that the MTE process is a powerful technique for the removal of both water and alkali components from lignite and younger biomass fuels like straw. Reductions of the concentration of sodium in lignite and potassium in straw between 70 and 85% are obtained. The results thus demonstrate, that the MTE process is also suitable for the upgrading of lignites and biomass fuels to prevent corrosion and slagging in power plants. The development of the plant and process engineering for the dewatering of lignite and for the combined leaching and dewatering of biomass fuels is presented and technological modifications required for the dewatering of waste materials and suspensions like galvanising sludge are described. The technical implementation is demonstrated based on the laboratory and technical scale dewatering units at the University of Dortmund and the pilot and demonstration plants located in Frechen and at the power plant Niederaußem. Efficiencies for different dry lignite fired power plant concepts with integrated mechanical/ thermal lignite dewatering are calculated and compared to the results obtained for other drying and dewatering processes. Depending on the origin and water content of the lignite, power plant efficiencies can be increased by up to 20 percent and specific CO2 emissions can be reduced by the same amount by the implementation of the MTE process in technical scale power plants. The results prove, that the MTE process is a remarkable advance compared to the existing methods.

Embora seja conhecido que a irradiação com laser de CO2 reduz a desmineralização do esmalte, efeitos colaterais como danos térmicos na superfície são comumente observados. A ocorrência dessas microfraturas e fissuras é um dos fatores que ainda comprometeM uma utilização segura in vivo. Sendo assim, o objetivo desTe estudo foi encontrar parâmetros de irradiação com laser de CO2 (?= 10,6 ?m) que resultassem no máximo efeito preventivo de cárie e no menor dano térmico. Três estudos foram conduzidos para avaliar separadamente três parâmetros da irradiação com laser. No primeiro estudo cinco densidades de energia diferentes, 0,1, 0,3, 0,4, 0,5 e 0,6 J/cm2 combinadas com altas taxas de repetição, 500, 154, 167, 182, 187 Hz, respectivamente, e 10 ?s de duração de pulso foram testadas. Após ter sido avaliado, qual delas resultou na maior inibição da progressão das lesões de cárie, um segundo estudo foi conduzido com cinco diferentes larguras de pulso, 5, 10, 20, 30 e 50 ?s, combinadas à mesma densidade de energia de 0,3 J/cm2. Encontrada a duração de pulso que causou o melhor resultado, um terceiro estudo foi realizado avaliando três diferentes números de pulsos sobrepostos, para a mesma densidade de energia e duração de pulso (0,3 J/cm2 e 5 ?s). Para os três estudos foram utilizados cubos de esmalte bovino, que tiveram as suas superfícies polidas. Após o tratamento das superfícies com laser, as amostras foram submetidas ao mesmo desafio cariogênico, uma ciclagem de pH de 8 dias. A desmineralização provocada foi avaliada medindo-se a profundidade das lesões em microscópio de luz polarizada. Avaliações adicionais da desmineralização foram realizadas para os estudos 2 e 3, utilizando-se a técnica de quantificação da fluorescência induzida por luz (QLF). Análises morfológicas da superfície e também da secção transversal foram realizadas com microscópio eletrônico de varredura. Diferentes grupos irradiados por laser apresentaram profundidades de lesão estatisticamente menores do que o controle (ANOVA, p

According to WHO, the addition of fluoride to milk could be considered as an alternative to water fluoridation for community-based caries prevention in childhood. School-based schemes in developing as well as industrial countries have demonstrated substantial benefits on oral health, but there are limited data available on the local events in the oral cavity after consumption of fluoridated milk. The general aim of the present investigations was to investigate the concentration of fluoride obtained in saliva and dental plaque after ingestion of Fmilk and to explore the possible effects on the oral ecology. A series of controlled studies were performed in vivo in which samples of saliva and dental plaque were collected and analysed with respect to fluoride content, microbial composition and acidogenicity. An in vitro study evaluated the effect on enamel lesion formation. In paper I, significantly increased concentrations of fluoride (p

Titelblatt, Deckblatt und Widmung Inhaltsverzeichnis Einleitung Literaturübersicht Ziel der Untersuchung Material und Methode Ergebnisse Diskussion Schlussfolgerung Zusammenfassungen Literaturverzeichnis Anhang, Eine Xerostomie wird meist rein symptomatisch mit Speichelersatzmitteln behandelt, die vorzugsweise eine remineralisierende Wirkung haben sollten. Ziel dieser Studie war es, die Auswirkungen potentieller Speichelersatzmittel auf Carboxymethylcellulose-(CMC)basis mit unterschiedlichen Oktakalziumphosphat-(OKP)sättigungen auf demineralisierten, bovinen Schmelz zu untersuchen. Aus 50 Rinderfrontzähnen wurden 200 Schmelzproben präpariert. Diese wurden in Kunstharz eingebettet und oberflächlich poliert. Ein Probendrittel wurde mit Nagellack abgedeckt (gesunde Kontrolle); anschließend erfolgte die Demineralisation der Proben (14 Tage; pH 5,5; 37 ºC). Ein Teil des demineralisierten Bereiches wurde daraufhin ebenfalls mit Nagellack abgedeckt (Kontrolle Demineralisation). Die Proben (n = 10) wurden anschließend für 14 Tage in 20 verschiedenen potentiellen Speichelersatzlösungen gelagert (37 ºC). Die einzelnen Ansätze enthielten hierbei 20 g/l CMC, 0,1 mM NaF sowie CaCl2 (0-32 mM) und KH2PO4 (0-52 mM) bei pH-Werten von 5,5 bzw. 6,5. Die OKP-Sättigungen der verschiedenen Lösungen wurden berechnet. Nach Versuchsablauf wurden Dünnschliffe hergestellt, die mikroradiografisch bezüglich der Mineralverluste und der Läsionstiefen ausgewertet wurden. Mit steigender Kalzium- und Phosphatkonzentration konnte eine Verbesserung des Remineralisationsvermögens beobachtet werden. Die Lösung mit einer OKP-Sättigung von 3,2 (2 mM CaCl2, 13 mM KH2PO4 und 1,9 ppm Fluorid, pH 6,5) war als einzige in der Lage, die demineralisierten Schmelzbereiche [mittlerer Mineralverlust (Standardabweichung) 1695 (302) Vol.% × µm] signifikant zu remineralisieren [587 (364) Vol.% × µm] (p < 0,05; t-Test). Eine weitere Zugabe von Kalzium und Phosphat (OKP-Sättigung: 15,8 und 66 bewirkte hingegen eine signifikante Reduktion des Mineralgehaltes. Hieraus kann geschlussfolgert werden, dass hochvisköse CMC-Lösungen mit einer OKP- Sättigung von 3,2 in vitro einen remineralisierenden Einfluss auf bovinen Schmelz besitzen, während Lösungen mit niedrigeren OKP-Sättigung bestenfalls eine neutrale Wirkung zeigen., Xerostomia is usually symptomatically treated by the administration of saliva substitutes. The aim of this in-vitro-study was to evaluate the effects of carboxymethylcellulose (CMC)-based solutions in combination with various calcium and phosphate concentrations and ratios on the mineral content as well as the lesion depth of demineralised bovine enamel specimens. Four commercially available products were tested for comparing reasons. From 60 freshly extracted bovine incisors 240 enamel specimens were prepared. The samples were embedded in epoxy resin and polished. The surfaces were partly covered with nail varnish, thus serving as control of sound enamel. The enamel specimens were stored in a demineralisation solution for 14 days. Subsequently, the demineralised area was partly covered with nail varnish. The samples (n = 10) were stored in 24 different solutions for 14 days at 37 °C that were renewed every 12 hours. The potential CMC-based saliva substitutes with 20 g/l CMC and various saturations with respect to apatites contained 0.1 mM NaF, CaCl2 (0-32 mM) and KH2PO4 (0-52 mM) at two different pH values (5.5 or 6.5). After the in-vitro-exposure the specimens were cut perpendicular to the enamel surface and the sections were ground to a uniform thickness. Contact microradiographs of the specimens were obtained and studied with a digital image analysing system. A dedicated software (TMR for Windows, version 2.0.27.2) was used to calculate mineral loss and the lesion depths. With an increase in calcium and phosphate added, an increased mineral gain can be observed up to the solution with the third highest saturation with respect to octacalciumphosphate (CaCl2 2 mM, KH2PO4 13 mM). Here significantly reduced mineral losses could be observed (p < 0.05; t-test). A further addition of calcium and phosphate reduced the mineral content. The commercially available products induced a significant mineral loss (p < 0.01; t-test); thus, the latter should not be recommended for dentate patients. Inferential it can be said that high viscous CMC based solutions are able to remineralise bovine enamel in vitro if containing high saturations with respect to OCP.

International audience; As far as the reduction of the environmental impact of production processes is concerned, the management ofliquid wastes of high salinity remains a key point. In this paper, the possibility to use electrodialysis for the improvement of the management of such problematic liquid wastes is investigated. The ED experiments are carried out to investigate the influence of the operating parameters on the ED performances, i.e. on the variation of the organic loss factor versus the demineralisation factor. It is demonstrated that the demineralisation can be accompanied by a change in the mineral composition, i.e. an increase of the sulphate to chloride ratio. A concentration limit is pointed out. Then, the influence of the salt composition on the biological degradation is investigated

Titelblatt und Inhaltsverzeichnis Danksagung Einleitung Literaturübersicht Ziel der Untersuchung Material und Methode Ergebnisse Diskussion Schlussfolgerung Literaturverzeichnis Materialliste Wesentliche Teile Meiner Familie, Ziel der Untersuchung: An Muzin gebundene Sialinsäuren sowie enthaltene Proteine sind dafür bekannt, Kalzium zu binden. Hierdurch könnte das Remineralisationspotential kalziumenthaltender, muzinbasierter Speichelersatzmittel gehemmt werden. Daher war es das Ziel dieser Untersuchung, den Effekt der Zugabe unterschiedlicher Kalziumphosphatkonzentrationen in Muzin enthaltenden Speichelersatzlösungen auf demineralisierten bovinen Schmelz in vitro zu evaluieren. Material und Methode: Bovine Schmelzproben wurden in Kunstharz eingebettet (Technovit 4071; Kulzer; Wehrheim, Deutschland) und bis zu einer Körnung von 4000 poliert. Partiell wurden die Probenoberflächen mit Nagellack abgedeckt (Kontrolle) und für 14 (19 Gruppen; n = 10) bzw. 28 Tage (3 Gruppen; n = 9) demineralisiert (37 °C; pH 5,0). Nach der Demineralisation wurden die Proben muzinbasierten Lösungen (30 g/l) unterschiedlicher Sättigungen mit einer Konzentration von 0,1 mM NaF, 0-20 mM CaCl2 und 0-52 mM KH2PO4 bei zwei unterschiedlichen pH- Werten (5,5 oder 6,5) 14 Tage lang ausgesetzt. Eine fluoridfreie Lösung sowie das kommerziell erhältliche Speichelersatzmittel Saliva Orthana® (Orthana, Kastrup, Copenhagen Denmark) dienten der Kontrolle. Die Differenzen bezüglich des Mineralverlustes (ΔMin) zwischen den Werten vor (min.d) und nach der Lagerung (min.e) in den unterschiedlichen Lösungen wurden anhand von Dünnschliffen (100 µm) mikroradiografisch ausgewertet. Ergebnisse: Das Allgemeine Lineare Modell zeigte für ΔMin ein signifikante Abhängigkeit vom Kalziumgehalt (p = 0,006), nicht aber vom Phosphatgehalt (p = 0,081) sowie dem pH-Wert (p = 0,114). Nur in der Gruppe der höchsten Sättigung in Bezug auf Hydroxylapatit war min.e im Vergleich zu min.d signifikant reduziert (p < 0,05; t-Test). Schlussfolgerung: Muzinbasierte Speichelersatzmittel sind bei einer adäquaten Zusammensetzung in der Lage, bovinen Zahnschmelz in vitro zu remineralisieren., Objective: Sialic acids and proteins bound to mucin are known to complex calcium, a mechanism that might hamper remineralisation of calcium-containing mucin-based saliva substitutes. Thus, the aim of this investigation was to evaluate the effects of adding various calcium phosphate concentrations to mucin-containing solutions on demineralised bovine enamel in vitro. Design: Bovine specimens were prepared, embedded in epoxy resin, and polished up to 4000 grit. Subsequently, the specimens surfaces were partly covered with nail varnish, thus serving as control of sound enamel, and demineralised (37 °C; pH 5.0) either for 14 (19 groups; n = 10) or 28 days (3 groups; n = 9), respectively. After demineralisation the specimens were exposed to mucin-based solutions (30 g/l) with various saturations with respect to apatites containing 0.1 mM NaF, CaCl2 (0-20 mM), and KH2PO4 (0-52 mM) at two different pH values (5.5 or 6.5). A fluoride-free solution as well as the commercially available saliva substitute Saliva Orthana® (Orthana, Kastrup, Copenhagen Denmark) served as control. The differences in mineral loss (DMin) between the values prior to (min.d) and after the storage (min.e) in the various solutions were evaluated from microradiographs of thin sections (100 µm). Results: The general linear model revealed a significant dependency for DMin on calcium (p=0.006) but not on phosphate (p=0.081) or pH (p=0.114). Min.e was only significantly reduced compared to min.d in the group with the highest saturation with respect to hydroxyapatite (p < 0.05; t-test). Conclusion: With an adequate composition mucin-based saliva substitutes are capable to remineralise bovine enamel in vitro.

Demineralised water is used as make-up water to compensate for losses in the condensate-boiler feed-water stream at power stations and other steam raising plants. Demineralisation plants are designed to produce pure water that contains virtually no impurities. Ion exchange is invariably used for demineralisation. Effective regeneration of exhausted resin is an important aspect to ensure optimal performance of the ion exchange process. Regeneration profiles were used in this investigation to determine the effectiveness of regeneration and to optimise the regeneration process. WaterSA Vol.29(4) 2003: 411-418

Preparation of make-up water in the complex centralised systems for the central heating, sanitary hot water, as well as for low-pressure steam generators, can be accomplished in several ways. However, water-softening treatment dominate in most cases. In the small decentralised as well as in industrial systems, complexity of the performance, monitoring and controlling in make-up water preparation processes sometimes is manifested as a certain problem. Therefore, in such systems simplicity in manipulation and maintenance could be important criterion. Nowadays mostly used way for preparation of make-up water is the use of ion exchange softening or demineralisation, but slowly a relatively new technology - membrane softening and purifying of water - has started to participate in the make-up water treatment. This paper gives a review of membrane technology processes and the analysis of comparison in efficiency and costs of both treatment technologies - membrane and ion exchange systems.

Cette étude concerne l'exploitation de l'électrodialyse dans le traitement d'effluents issus de l'industrie agro-alimentaire. Le fluide d'étude choisi est le lactosérum. La compréhension des interactions ioniques au cours de la déminéralisation de solutions synthétiques de composition ionique connue donne lieu à une étude expérimentale et une modélisation. Le modèle proposé permet de simuler des déminéralisations par électrodialyse à partir d'un calcul des mobilités apparentes dans la membrane des ions présents dans le milieu. Le modèle a egalement permis de mettre en évidence les interactions entre équilibre de complexation et élimination du calcium par électrodialyse dans le lactosérum. Les résultats sont exploités dans la mise en oeuvre d'un procédé de précipitation thermique de l'α-lactalbumine à son point isoélectrique en utilisant comme matière première un lactosérum démineralisé. Cela entraîne la valorisation d'une partie du lactosérum et contribue à son recyclage.