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Biomass energy for heating is going to be part of the spectrum of renewable energy sources. However, biomass combustion produces emissions of various pollutants with negative effects at both local and global scales. To reduce some of the locally important pollutant load, thermally treated biomass fuels may offer a partial solution. In this study, two biomass feedstocks, i.e., spruce chips and rapeseed straw, were thermally treated at 300 °C to produce biochars. Subsequently, both original materials and biochars were burned in a 25 kW retort combustion device. In both cases, the biochar showed lower emissions of carbon monoxide and nitrogen oxides, usually almost across the whole range of tested combustion conditions. In total, for the emission production per unit of net calorific value, the spruce biochar showed reductions in CO and NOx productions of 10.8% and 14.5%, respectively. More importantly, in rapeseed straw biochar, the difference was more pronounced. The total production was reduced by 28% and 42%, again in CO and NOx emissions, respectively.

As a source of renewable energy, agricultural by-products after pre-processing and cleaning in post-harvest lines can be used as a feedstock for the production of pellets or briquettes. This can be achieved by determining the physicochemical properties of the by-products. Groundnut pods, maize cobs and the husks of rice, millet and sorghum were considered, and their properties were determined, which were then compared with the standard properties of pellets and briquettes to ascertain their viability as a feedstock for the pellet or briquette production. The by-products were transported from Nigeria to the Czech Republic and the research was carried out at the Department of Technological Equipment of Buildings, the Faculty of Engineering, Czech University of Life Sciences Prague. The moisture content, ash content, calorific value, nitrogen content and sulfur content were the properties considered of the by-products. Groundnut pods and maize cobs with a calorific value of 17.48 MJ.kg-1 and 16.25 MJ.kg-1, an ash content of 3.46% weight and 1.79% weight, a nitrogen content of 1.24% weight and 0.44% weight and a moisture content of 7.92 weight and 7.56% weight, respectively, were discovered to fulfill all the requirements for graded non-woody pellets A. With the exception of rice husks and millet husks, which were discovered to have high ash contents and low calorific values, all the by-products fulfilled the standard requirements for one or more grade of pellet/briquette. They can, therefore, be used as a good feedstock for pellet or briquette production.

The fourth generation of the Sloan Digital Sky Survey (SDSS-IV) has been in operation since 2014 July. This paper describes the second data release from this phase, and the 14th from SDSS overall (making this Data Release Fourteen or DR14). This release makes the data taken by SDSS-IV in its first two years of operation (2014-2016 July) public. Like all previous SDSS releases, DR14 is cumulative, including the most recent reductions and calibrations of all data taken by SDSS since the first phase began operations in 2000. New in DR14 is the first public release of data from the extended Baryon Oscillation Spectroscopic Survey; the first data from the second phase of the Apache Point Observatory (APO) Galactic Evolution Experiment (APOGEE-2), including stellar parameter estimates from an innovative data-driven machine-learning algorithm known as "The Cannon"; and almost twice as many data cubes from the Mapping Nearby Galaxies at APO (MaNGA) survey as were in the previous release (N = 2812 in total). This paper describes the location and format of the publicly available data from the SDSS-IV surveys. We provide references to the important technical papers describing how these data have been taken (both targeting and observation details) and processed for scientific use. The SDSS web site (www.sdss.org) has been updated for this release and provides links to data downloads, as well as tutorials and examples of data use. SDSS-IV is planning to continue to collect astronomical data until 2020 and will be followed by SDSS-V.

Maize grown on sloped areas is susceptible to surface runoff and soil erosion, especially if traditional technology with tillage is employed. As a result, other solutions are being sought that address this risk and are acceptable to farmers. The combination of inter-row cultivation with the formation of small reservoirs appears to be a suitable alternative solution applicable in traditional corn cultivation. In the years 2020, 2021, and 2022, three plots of land in southern Bohemia, Czech Republic, were selected for testing, on which this approach was tested. During the field experiments, three variants were compared each year: inter-row cultivation with reservoirs, inter-row cultivation only, and a control without any mechanical intervention. All variants were subjected to rain simulation, from which the surface runoff was evaluated. The highest retention of runoff was manifested with reservoir cultivation by 2.4–4.2 min, compared to the cultivated variant, and 2–4.2 min compared to the control. This result would correspond to a difference of 5.7–9.8 mm retained precipitation and 4.6 to 7.3 mm, respectively. The hydraulic conductivity of the soil was evaluated after canopy closure. The lowest values were invariably reached in the reservoirs, up to 88% lower than with the cultivated variant and 79% lower than the control. The fresh matter yield of forage maize was shown to be inconclusively higher by up to 10% in 2020 and 2022 in cultivation with reservoirs. However, the dry matter yield was always lower in the variant with reservoirs compared to inter-row cultivation only. Overall, reservoir cultivation appears to be an effective method for the retention of rainwater on agricultural land with a slope up to 6° without a significant effect on the yield of maize.

The issue of carbon monoxide and nitrogen oxides emissions into the atmosphere is very current. This article thus focuses on the assessment of elemental composition of selected herbal biomass species and emission concentrations during combustion in a commonly available grate combustion device for briquetted fuel. In tests, emission concentrations were evaluated in contrast to the oxygen concentration in flue gas and flue gas temperatures. Samples of camelina (Camelina sativa), giant miscanthus (Miscanthus gigantheus), reed canary grass (Phalaris arundinacea L.) and sorghum (Sorghum bicolor) were used. Elementary and stoichiometric combustion analyses were conducted for these samples (LECO AC-600 semi-automatic calorimeter, CHN628 + S elemental analyser and LECO TGA-701 analyser). Analyses of C, H, N and S concentrations and calorific values showed that samples of briquetted herb biomass had insignificant differences and could be used for energy purposes without limitation. The limiting factor was the high amount of ash, which amounted to 6.59% of dry weight in reed canary grass briquette sample. Furthermore, a high percentage (1.91% wt.) of nitrogen was observed in reed canary grass briquettes. Such a high amount of nitrogen during combustion tests resulted in an increase in NOx emission levels in flue gas of the Phalaris arundinacea L. sample, in which it reached the maximum concentration of 375.20 mg·m−3. The combustion tests showed that even under steady-state conditions, high concentrations of carbon monoxide could not be avoided for tested briquetted biofuels without active regulation of the combustion process.

Regarding the increased surface runoff from production areas, wide-row crops grown on slopes are considered risk crops. By reducing the surface runoff, it is possible to mitigate the negative effects on both the soil and the plants and positively influence the subsequent production, e.g., after application of de-stoning before planting. During this research, the tied ridging method was applied during planting by a two-row planter in both central and tractor trail furrows in potato rows and on the slope of 8.8% compared to a control plot without this treatment. Rainfall and surface water runoff were monitored, and the crop yields were compared. During three monitored years, up to 86% of the runoff water in the central furrows was saved compared to the control, whereas it was up to 72% in the wider furrows for tractor travel. The total yield was increased on the treated area, however, the increase could not be statistically proven.

Under laboratory conditions, seepage of liquid cattle manure with dry matter content of 3-8% through subsoil was studied in relation to its dry matter content and period of storage. Statistical dependence of the total amount of eluate on the dry matter has been found (P = 0.0013). A hypothesis was also confirmed that liquid cattle manure shows a sealing effect during storage. It was found that the average value of coefficient of permeability decreases as soon as 48 hours after the start of storage under the value 5.56171 × 10-6 cm.s-1, which, according to peer reviewed literature, is not hazardous to the environment. The results will help in designing projects of liquid cattle manure reservoirs and assessment of their effect on the environment.

In the experiment, a group of 10 dairy cows was housed in a pen bedded with various amounts of wheat straw (5.2-13 kg/cow per day). The resulting mixture of feces, urine and bedding was stored in cubic containers with a volume of 1.5 m3. At regular intervals, the containers containing manure were weighed and manure leachate production was assessed. Daily changes in individual monitored variables over time in accordance with the amount of bedding per livestock unit per day (1 livestock unit = 500 kg live weight) were modelled using nonlinear mixed regression models. It was determined that manure weight changes and daily production of manure leachate released from manure stored in containers were related to storage duration and bedding amount in a statically significant manner. The results support the hypothesis that the amount of bedding has a statistically significant effect on the properties of manure stored in a manure pile.

The hardest tissue in the human body is the enamel which covers the anatomical crowns of teeth. It must be resistant to mechanical stress and the chemical attack of many substances from food, drinks and products of the metabolism of bacteria present in the oral cavity. These low pH substances dissolve the mineral components of enamel, cause tooth demineralization, and lead to decay or erosion damage with the irreversible loss of dental hard tissues and the necessity of their reconstruction. The range of dental materials intended for dental tissue reconstruction is extensive. Dental amalgam can be mechanically applied into the strongly stressed lateral segments of teeth. The use of amalgam is, however, in decline, with the possible health risks attributed to it, coupled with the need to extensively prepare tooth tissue promoting a shift towards using aesthetically and biologically favourable dental ceramic and polymeric materials instead. Current developments also concentrate on these materials to reinforce this, with polymeric composite materials based on methacrylates with varying amounts of inorganic fillers at the forefront. These materials are distinguished by their good mechanical and aesthetic properties and wear resistance. However, polymerization shrinkage and a strong hydrophobic nature does not allow for their direct bonding to hard dental tissues. Risks associated with the release of residual free monomers from the structure to the environment, which may cause health complications, mainly allergic reactions in sensitive individuals, have been monitored recently. Further development in the field of composite materials aims to reduce or completely eliminate these negatives.

Utilization of waste suitable as a fuel for small combustion devices is a very important issue. Therefore, this article analyzes selected waste materials from agriculture and maintenance of municipal vegetation. The pellet samples from composting had very high ash content (22.39 and 36.85% wt.), which resulted in low values of net calorific value (12.66 and 10.24 MJ/kg), but also in bad properties of these samples in high concentration of harmful emission. Other problematic fuel samples were pellets from maintenance of city vegetation and reed canary grass, for which high concentration of carbon monoxide was measured during combustion process. The device used for these experiments is based on burner furnace. Combustion conditions could be improved by more uniform fuel supply to the burner and better control of combustion air. Boiler with advanced combustion control can reach better results during combustion process. Results in this article are valid for tested materials combusted in simple pellet burner with limited ability to control combustion process.

Diffuse alveolar hemorrhage (DAH) is a life-threatening complication, especially of systemic vasculitis, but also of other connective tissue diseases. The trick is the fact that for some patients, a DAH attack is the first manifestation of the disease. A typical triad of symptoms includes rapidly developing dyspnea, anemization, and the presence of diffuse alveolar hemorrhage on bronchoalveolar lavage examination. Hemoptysis is not a reliable indicator, it occurs only in a third to a half of patients. HRCT will show extensive clouding of the lung fields, usually bilateral. The acute prognosis depends on the timeliness of the diagnosis or initiation of intensive immunomodulating therapy. Urgent determination of the presence of ANCA antibodies (immediately) can be of significant help. Acute bronchoscopy with BAL is an essential part of the diagnosis. Treatment of an acute attack of DAH consists of i.v. administration of pharmacological doses of methylprednisolone and early initiation of i.v. cyclophosphamide or rituximab therapy according to usual schemes. Concomitant rapidly progressing anuric renal failure occurs in approximately half of patients with a severe course and requires the use of elimination methods. Overcoming respiratory failure may require the temporary use of extracorporeal oxygenation (ECMO). If the acute phase of DAH can be managed, the restitution of lung and renal functions is significant, and chronic dialysis is required less often. In the further course, the prognosis of the patient probably does not differ significantly from the prognosis of the underlying disease. Due to the significant number of patients in whom the attack of DAH is the first manifestation of a systemic disease, the possibility of DAH should be considered in any case of rapidly developing severe respiratory insufficiency without an obvious previous cause. [ABSTRACT FROM AUTHOR]

In this article, the effect of increasing dry matter content and reaction time of hydrothermal carbonization on mass yield of biochar was studied. Carbonization took place in batch experiments in a pressure vessel. Results have confirmed the assumption that the mass yield of biochar would increase with growing dry matter content in the initial solution and also with reaction time at reaction temperature of 200°C. It was found that components of the liquid product that remain in the biochar have a measurable impact on its mass yield. Mixing of the reactor proved to have a considerable effect on the mass yield as well. Biochar produced in absence of mixing had higher pore volume and higher yield. This was evident even after subtracting the equivalent liquid phase dry matter in the biochar after drying.

Introduction: The disinfection of dental impressions is necessary in terms of preventing the transmission of infection from patients' blood or saliva before processing at a dental office or laboratory. The adverse effects of the disinfection process can result in dimensional changes of the dental impressions, a change in surface quality and loss of the ability to reproduce the details of hard and soft tissues in the oral cavity. All these potential negative effects can ultimately influence the final prosthetic work. Aim: This study aimed to assess "in vitro" the impact of several commercially available disinfectants on detail reproduction and the dimensional changes of dental impressions made from various types of dental impression materials and their compatibility with dental gypsums. Methods: In this study alginate (Ypeen, Alligat fast set, Elastic Cromo) and elastomer (Variotime Medium Flow, Xantropren L blue, Impregum Soft) dental impression materials in combination with four disinfectants (Aseptoprint Liquid, Zeta 7 solution, Silosept, Dentaclean Form ) and gypsums type 3 (Mramorit Blue) and type 4 (BegoStone plus) were tested. The methods were executed using technical standards ČSN EN 21563 Dental alginate impression materials and ČSN EN ISO 4823 Dental elastomeric impression materials. Detailed reproduction of the dental impressions, their dimensional changes and compatibility with gypsum were evaluated on the impressions of the metal block with lines of defined dimensions. Dimensional change was defined as the percentual change of the distance between lines reproduced on disinfected impressions and the lines of defined dimensions on the metal block. The results were statistically analysed using Statistica 12 software (StatSoft Inc., Tulsa, USA). Two-factor and one-factor analysis of variance ANOVA with Tukey HSD post-hoc tests at the significance level of 0,05 % were used. Results: The detail reproduction of dental impressions and their compatibility with gypsum worsened when the alginate impression materials were combined with disinfectant Dentaclean Form. The surface of other tested impression materials remained unchanged after disinfection, as were the reproduction of details and compatibility with gypsum. Dimensional changes after disinfection were the highest in alginate material Elastic Cromo and the shortest in polyether material Impregum Soft. Conclusion: The disinfection of dental impressions is currently a necessary step before further processing in dental laboratories. However, it was confirmed that the desired properties of impressions may be negatively affected by disinfectant, particularly in the case of alginate materials. It is therefore always important to approach the selection of specific disinfectant with respect to the manufacturer's recommendations and the available information regarding this issue.

Introduction: The aim of our prospective study was to define endoscopy appearance of the small bowel in healthy volunteers. Method: Forty-two healthy volunteers underwent wireless capsule endoscopy, clinical investigation, laboratory tests, and completed a health-status questionnaire. All subjects were available for a 36-month clinical follow-up. Results: Eleven subjects (26%) had fully normal endoscopy findings. Remaining 31 persons (74%), being asymptomatic, with normal laboratory results, had some minor findings at wireless capsule endoscopy. Most of those heterogeneous findings were detected in the small intestine (27/31; 87%), like erosions and/or multiple red spots, diminutive polyps and tiny vascular lesions. During a 36-month clinical follow-up, all these 42 healthy volunteers remained asymptomatic, with fully normal laboratory control. Conclusions: Significant part of healthy subjects had abnormal findings at wireless capsule endoscopy. These findings had no clinical relevance, as all these persons remained fully asymptomatic during a 36-month follow-up. Such an endoscopic appearance would be previously evaluated as “pathological”. This is a principal report alerting that all findings of any control group of wireless capsule endoscopic studies must be evaluated with caution.

he aim of the experiments is determination of emission concentrations in the observed substances produced in exhaust gas during combustion of various mixtures of waste biomass compacted samples. The samples were pressed into the form of briquettes with a diameter of 65 mm. During the actual measurements the following parameters were monitored: emissions of carbon dioxide (CO2), carbon monoxide (CO), nitrogen oxides (NOx) and flue gas temperature depending on the excess air coefficient. Measurements of emission parameters were carried out in storage heater fireplace with nominal heat output of 8 kW. During the measurements high concentrations of carbon monoxide in excess of the value of 5,000 mg/m3 were determined, especially in the samples of waste from corn cleaning and wheat straw. The results show an excess air factor optimum adjustment on value 3, where the combustion device achieves optimum parameters of CO and NOx emissions. The results of emission measurements confirmed that the excess air is a very important operating variable which affects both monitored emissions concentrations and the combustion temperature in the fireplace.

The aim of our study was to analyze the precision of fused-deposition modeling (FDM), polyjet technology (PJ), stereolithography (SLA) and selective laser sintering (SLS) and to evaluate some interesting indications of these methods in clinical practice. Forty upper dental arches were scanned using a 3Shape Trios 3R optical scanner system and 3D models were made. An Atos II 400 optical 3D scanner was used for calculating the coordinates of points by optical triangulation, photogrammetry and fringe projection. Each model was scanned from a minimum of 56 positions to evaluate global coordinates. Surface morphology was evaluated with an Alpha Step IQ profilometer and a JSM 5510 LV scanning electron microscope. From the measurements in cross-sections it was evident that the deviation shifted by approximately 0.1 mm. The smoothest and most homogeneous sample was SLA. SLS and SLA samples showed the most similar results in comparison of perpendicular directions (homogeneity). FDM and PJ materials exhibited significantly greater roughness in the printing direction than in the perpendicular one, which is most likely caused by the technology selected and/or print parameters. Clinical applications have demonstrated unusual treatment options for patients with rare diseases.

Introduction: The comparison of tissue quality and its restoration after contact, and non-contact Er: YAG (2940 nm) laser radiation ablation was evaluated. Methods: Laser setting for contact ablation was 250 mJ/pulse, pulse repetition rate 15 Hz, average power 3.75 W. For non-contact ablation these values were: 600 mJ/pulse, 6 Hz, 3.6 W. Structure of enamel and dentin after laser ablation was analyzed in scanning electron microscope. All cavities were filled by sonic-activated composite resin. Chemical and mechanical bond was observed in scanning electron microscope.Microleakage was assessed quantitatively by the degree of methylene blue dye penetration. Fischer exact test (p < 0.05) was used for statistical evaluation. Results: Contact and non-contact laser treatments prepared similar cavities (5167.31 μm versus 5356.31 μm). Defocusing of non-contact therapy has direct influence on the dye penetration microleakage presence (481.19 μm versus 611.94 μm) but this increase was not statistical significant. Conclusion: Cavity prepared by contact mode with sonic-activated composite filling protects microleakage formation.

Introduction: An adhesive bond between hard dental tissues and composite reconstructions is exposed to mechanical load, water, bacteria, enzymes and different chemical compounds. These factors could impair durability and resistance of composite reconstructions. In contrast with extensive research of negative influence of water on degradation of adhesive bonds, the influence of chemical substances on adhesive bond has not been investigated to a greater extent. Aim: The aim of the experimental part of the thesis was to evaluate the influence of hydrogen peroxide containing tooth-whitening products and mouth rinses containing chlorhexidine and fluoride on a long-term stability of class V composite restorations created using four contemporary adhesive systems by a microleakage method. Materials and methods: The following adhesive systems were investigated: total-etch Gluma Comfort Bond (GLU), and self-etch adhesives Clearfil SE Bond (CLF), Adper Prompt (ADP) and iBond (IBO). Standardized class V cavities were prepared in 192 extracted human teeth (one cervical margin in the cementum and one in the enamel). Subsequently, the cavities were restored using microhybride composite Charisma. The specimens were then exposed to the tooth whitening system Opalescence PF 20, mouth rinse Corsodyl containing chlorhexidine and mouth rinse Elmex containing aminfluoride. The exposure times were 2 and 6 months, the whitening system was applied in 25 cycles each 8 hours apart. The control group included restorations exposed to distilled water for 24 hours, 2 and 6 months. After the exposure the specimens were immersed in 2% methylene blue solution for 24 hours. The microleakage data were analyzed using Kruskall-Wallis, Mann-Whitney and Wilcoxon tests (p = 0.05). The surface morphology was assessed using scanning electron microscopy. Results: After being exposed to water, the specimens bonded by GLU a CLF showed a significantly lower microleakage score in both enamel and dentine. ADP and IBO showed a significantly higher microleakage, especially in the enamel. Compared to the control group, there were only small and statistically insignificant changes in the dentine and enamel microleakage. Differences were observed, when the samples were exposed to chlorhexidine- and fluoride-containing mouth rinses. Compared to the control group, there were statistically significantly lower microleakage scores, particularly for ADP and IBO. Conclusions: The results suggest that the risk of impairment of the adhesive bond stability is higher in self-etch adhesive systems with simplified application procedures. The insignificant effect of the peroxide tooth whitening system and the unexpected increase in resistance of restorations exposed to mouth rinses inevitably lead to certain doubts about appropriateness of the recommended microleakage tests for systems with different bond to the enamel and dentin. Thus, it remains unclear if the tested products for oral hygie-ne really increased the adhesive bond resistance, or the observed effect resulted from the microleakage reduction due to precipitation of components of the exposure media.

The article assesses the energy use of solid biofuels (wheat and rape straw) and their blends with suitable additives (cocoa husks, brown coal and coal sludge). The elemental and stoichiometric analysis evaluates their suitability for energy recovery. Furthermore, thermal emission characteristics in automatic hot water boiler VERNER A251 are observed. The results of thermal emission measurements show that all samples meet the requirements of the Directive No. 13/2006 for carbon monoxide (2,000 mg/m3). The average nitrogen oxides emission concentrations exceed emission limits compared with the Directive No. 13/2006 (250 mg/m3) for all samples of solid biofuels. One reason is the high temperature in the combustion chamber that increases combustion temperature and results in high temperature of nitrogen oxides. Another problem is carbon monoxide that depends on the coefficient of excess air. The value of this coefficient drops under its optimum (2.5) and subsequently follows an increasing trend.

Introduction: Ankylosing spondylitis (AS) is an inflammatory rheumatic disease characterized by the development of osteoproductive changes in the spine which could possibly result in ankylosis. Treatment with tumour necrosis factor alpha (TNFα) inhibitors has proved to be an important step forward in the treatment of this disease, but for the time being it is not clear whether it favourably influences radiographic progression of the disease. Vascular endothelial growth factor most probably plays a role in the development of osteoproductive changes and recently its predictive influence on radiographic progression has been demonstrated. Bone morphogenic protein 2 (BMP-2) participates in the regulation of bone proliferation and its increased serum level has been demonstrated in patients with advanced AS and correlated with the degree of radiographic changes. Aim: The study aims to evaluate the VEGF and BMP-2 levels in patients with ankylosing spondylitis and how these levels relate to the concurrent treatment with TNFα inhibitors. Methods: Sera were evaluated from patients at the Rheumatologic Clinic of the Hradec Králové Faculty Hospital who fulfilled the modified New York Criteria for AS (n = 55). In these patients, the parameters of the activity of the disease (BASDAI = Bath Ankylosing Spondylitis Disease Activity Index, CRP = C-reactive protein) and the concurrent therapy (TNFα inhibitors, n = 21, vs. non-anti TNFα, n = 34) were recorded. The levels of VEGF and BMP-2 were analyzed using the ELISA method. Results: In patients treated with TNFα inhibitors, a significantly lower VEGF level was found when compared to untreated patients (140.3 (109.4; 262.2) vs. 261 (172.4; 396.6) pg/ml; p = 0.02). No difference was found between BMP-2 levels in both groups (treated vs. untreated patients) (254.8 (2301; 267.3) vs. 261.1 (248.6; 273.5) pg/ml; p = 0.24). A correlation analysis did not reveal any relationship between VEG F and BMP-2 (r = 0.057; p = 0.68). Serum levels of VEGF correlated with serum levels of CRP (r = 0.56; p = 0.00001) and the BASDAI value (r = 0.33; p = 0.015). Conclusion: Significantly lower VEGF levels were found in patients treated with TNFα inhibitors versus the untreated patients. These findings are in harmony with some hitherto published analyses and may give evidence of a favourable effect of TNFα inhibitors on radiographic progression. Neither influence on the BMP-2 level by treatment with TNFα inhibitors nor correlation with VEGF levels was demonstrated.

Introduction: Composite restorations undergo degradation in the oral cavity, which may compromise their aesthetic and functional properties, cause failure of marginal integrity, increased abrasion or even partial fracture of the filling. Instead of complete removal of such restorations, they can be repaired. Aim: To study the bond strength of a new composite resin to an aged composite substrate after a 4-month storage in distilled water or sodium laurylsulphate solution (SLS). Two various surface treatments and two different adhesive systems were tested. Materials and methods: Light cured specimens of a micro-hybrid composite (Filtek Z250, shade A2) were aged in distilled water (37 °C) for 5 months. Composite surface was prepared either by grinding (SiC paper P320, mean grain size 46 µm, equivalent to red diamond bur) or by air abrasion (Rondoflex; Al2O3 50 µm; 3.2 bar; 60 s). Composite build-ups were made from the same composite material using two adhesive systems (Optibond FL, Gluma Comfort Bond). The microtensile bond strength (n = 13-16) was measured after a 4-month storage of specimens at 37 °C in distilled water or in a solution of sodium lauryl sulfate (1.5 wt. %). Control specimens were stored in distilled water for 24 hours (37 °C). Results: A decrease of the bond strength compared to the control group on the ground surface after the 4-month storage in distilled water or SLS was found to be adhesive system- dependant. The bond strength for Optibond FL decreased by 52% in SLS only (p < 0.001), but for Gluma Comfort Bond it decreased by 45% in distilled water (p < 0.001) and by 61% in SLS (p < 0,001). On the air-abraded surface the bond strength decreased only for Optibond FL in SLS (p < 0.01), by 31%. Conclusion: Long-term durability of composite repair can be maintained by preparing the original composite surface using air abrasion. The effect of the adhesive system on the bond strength was not significant.

Article without abstract

Over the recent years, dental curing lights as well as light-cured materials have been undergoing rapid development, which makes choosing a curing light guaranteeing the optimal polymerization degree difficult. The paper summarizes critical characteristics of curing lights necessary for reliable polymerization of light-cured composite materials, glass-ionomer cements and adhesive systems with different types of photoinitiators. The effect of emission-spectrum width on the polymerization degree of composite material is documented with polymerization of two typical composite materials with different photoinitiators and light-cured using quartz-tungsten-halogen lamp and LED lights with narrow and wide emission band. Values of surface Knoop hardness numbers revealed that among currently available curing lights, in particular LED with two or more types of diodes emitting broad-range blue light achieve the versatility and efficiency of halogen lights, currently the gold standard in light curing.

The objective was to compare efficacy of several types of halogen and LED polymerization lamps in curing restorative composite materials. Halogen lamps Heliolux DLX1 (Ivoclar Vivadent) and Megalux Fast Cure (MegaPhysik) and LED lamps DioPower (CMS Dental), Translux Power Blue (Heraeus Kulzer), BluePhase C8 (Ivoclar Vivadent) of a narrow spectral emission (group LED 1) and G-Light (GC, USA) and BluePhase G2 (Ivoclar Vivadent) of a broad spectral emission (group LED 2) were used. Curing efficacy was evaluated by measuring the composite hardness on the top irradiated and bottom not-irradiated surfaces of 2 mm thick specimens prepared from radically initiated dimethacrylate-based composite material Charisma (Heraeus Kulzer) and epoxy-based cationically polymerized composite material Filtek Silorane (3M ESPE). In curing of both composite materials a significant effect of the polymerization lamp on composite hardness and hence, polymerization degree was observed. The highest hardness of the composite material Charisma was found after polymerization with the halogen lamps and also BluePhase G2 of a broad spectral emission. With the epoxy-based Filtek Silorane the highest surface hardness was reached with both LED 2 and halogen lamps. In spite of limited number of polymerization lamps tested it seems obvious that the highest polymerization degree can be reached with polymerization lamps of broad spectral emission, such as high-power halogen lamps or LED lamps equipped with diodes emitting light in a short wavelength range.

Peroxide bleaching systems may affect resin composite restorations through their strong oxidative effect. The objective was to investigate the influence of bleaching systems on long-term stability of marginal integrity of composite restorations and composite surface resistance. Class V cavities were prepared at the enamel-dentine junction and filled using a total-etch adhesive system Gluma Comfort Bond (n=36) and self-etching adhesive iBond (n=36) in combination with the microhybrid resin composite material Charisma. The peroxide bleaching gel Opalescence PF 20% (20 wt. % carbamide peroxide) was applied 25 times on the restorations. The control groups were exposed to distilled water for 24 hours and two months before a microleakage test was performed. Composite hardness was characterized after 0, 2, 7, 14 and 25 applications of the gel and compared with the control group (each n=5) exposed to distilled water for two months. Surface morphology was evaluated using scanning electron microscopy. After the gel application no significant changes in marginal integrity were found for both groups of samples. With Gluma Comfort Bond due to its high bonding performance and with iBond due to its decreased performance on enamel causing marginal integrity failure at the beginning of the experiment. On the other hand, pronounced surface porosity and decreased hardness of the composite material indicated its significant degradation in the presence of the bleaching gel.

A shear bond strength and fractography analysis was used to evaluate reliability of nine total- and self-etching adhesives OptiBond FL, Gluma Comfort Bond, Prime&Bond NT, AdheSE, Adper Prompt, Adper Prompt L-Pop, Clearfil SE Bond, Xeno III and iBond. A critical bond strength at which 10 % samples failed was used as a measure of the adhesive reliability. Significant differences in reliability and also in mode of their fracture were found between total- and self-etching systems and also in adhesives in these groups. The highest reliability and mixed mode of fracture were found with group of classical total-etch 3- and 2-step adhesives OptiBond FL a Gluma Comfort Bond and also with 2-step self-etching AdheSE and Clearfil SE Bond. With these adhesives both high bond strength and highly predictable properties can be expected. Compromised reliability as manifested in decreased bond strength and predominantly less energetically demanding cohesive fractures of the adhesive layer or less frequently mixed fractures occurred for Adper Promt, iBond a Xeno III. On the other hand, Prime & Bond NT and especially Adper Prompt L-Pop in blisters were characterized as systems with a low reliability. Adhesive properties of self-etching systems might decrease as a result of aging processes during their shelf-life.

With the exhaustion of fossil energy sources in sight, the importance of the renewable sources of energy becomes one of the major conditions for permanently sustainable development not only in agriculture, but also in the society as a whole. The growing use of biodiesel has opened other areas of utilising the by-products from the manufacture of rape seed oil methyl ester (FARME) as an energy source, used in the combustion equipment designed for these alternative fuels. The aim of this paper is to assess the feasibility of utilising the by-products from the production of rape seed methyl ester as a source of energy, from ecology and economy aspects of the combustion equipment used. Therefore, the study is focused on the concentration of emissions generated by burning FARME, and distillation of residuals from FARME production plants. An important objective of this study lies in the determination of the stoichiometry characteristics of rape seed oil methyl esters and distillation residuals from FARME production plants. The following parameters are set by calculations: fuel heating power, oxygen amount (air) necessary for ideal combustion, flue gases amount and composition, and flue gases specific weight.

Energy is one of the global challenges attracting more concern at both local and international levels due to its impact on health and the environment. Ensuring accessibility to sustainable, affordable, reliable and modern energy is one of the SDG goals intended to be achieved before 2030. The standard of living of a family is determined by the type of energy and pattern of its utilization by the households. However, many households in developing countries are not using alternative energy sources despite their abundance and potential. This study investigates the predominant energy sources and drivers of intention to use alternative ones as cooking energy among households in Northeastern Nigeria. Three hundred and thirty-nine (339) households were selected using a multi-stage sampling procedure for the study, and data were collected using a structured questionnaire. The result revealed that firewood and charcoal were the dominant energy sources used for cooking by households (63.13 % and 52.37 %, respectively) due to their relatively low cost and ease of access. Electricity, LPG, and solar are the cooking energy sources that over 90 % of households are willing to adopt as alternatives. The ease of using the alternative cooking energy sources their availability and accessing energy information via radio, NGOs and universities/research institutions affect the household's intention to use alternative cooking energy sources in a positive way. Ensuring a constant supply of electricity, subsidizing solar PV, making LPG available and affordable to households, provision of clean and modern stoves at a subsidized price and collaboration with universities, NGOs for awareness creation will help reduce deforestation and over-dependence on firewood, thereby protecting the health and the environment. • Cooking energy is one of the global challenges, especially in developing countries • Firewood and charcoal are the dominant cooking fuels in Northeastern Nigeria • Cost and availability drive households toward using traditional biomass for cooking • Households are willing to adopt electricity, LPG and solar for cooking • Alternative energy sources should be affordable and easy to use [ABSTRACT FROM AUTHOR]

The target of the thestudy was to compare the reliability of adhesive systems of Vth. and VIth generation by thermocycling according to method ISO/TS 11405:2003 (E). For comparison there were chosen two representatives from each group - from the Vth generation materials Single Bond Adper and Prime&Bond NT and from the VIth generation materials Prompt-L Pop Adper and Xeno III. The materials of the Vth generation were combined with advised etching gels and by all adhesives the directions for use were strictly followed. Adhesive systems were combined with material Spectrum TPH. Each adhesive system was tested on 10 samples of intact third molars. The results showed extensive variability among reliability single adhesives without dependence to generations, that means self-etch or conventional total-etch. While measuring microleakage according to ISO/TS 11405:2003 (E) was the most reliable Prime&Bond NT, with score 12, than Xeno III with score 26. Between reliability of Single Bond Adper (score 37) and Prompt L-Pop Adper (score 38) there was no significant difference. The results demonstrated no significant difference between single generations of adhesive systems and proved that the quality of each product is the most important, whether it belongs to self-etch or conventional total-etch generations.

Background. The purpose of study was to evaluate the diagnostic yield of capsule endoscopy for NSAID-induced enteropathy and clinical, laboratory, and endoscopic characteristics of disease in patients with rheumatoid arthritis. Methods. 37 rheumatoid arthritis patients (30 women; mean age 55) treated with NSAIDs (>1 month), presented with anaemia and/or positive faecal occult blood testing, entered the study and underwent capsule endoscopy (EndoCapsule; Olympus), laboratory tests, and filled in questionnaires. Results. The prevalence of NSAID-induced enteropathy diagnosed by capsule endoscopy was 68% (25/37), classified as mild (red spots or erosions) in 18 (49%), moderate (10–20 erosions) in 4 (11%), and severe enteropathy (>20 erosions or ulcers) in 3 (8%) patients. We did not find statistically significant relationship between the enteropathy and gender, age, haemoglobin, leukocytes, albumin and CRP, or dyspepsia. The difference between subgroups of NSAIDs according to the COX specificity was not statistically significant. Conclusions. Capsule endoscopy is a highly accurate noninvasive method for evaluation of NSAID-induced enteropathy. It was revealed in a substantial section of the patients with rheumatoid arthritis and occult gastrointestinal bleeding, mostly classified as mild damage. No simple clinical or laboratory markers of the presence or severity of NSAID-induced enteropathy were recognised. This trial is registered with DRKS00004940.