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Rodents cutting the installation system with their teeth were a frequent issue with electric installation in the era of classical architecture. However, contemporary architectural systems with photovoltaic sources of energy, accompanied by premises' smart systems of information and energy transfer, have microorganisms destroying the optical and other types of installation. This work represents building systems of residential premises with photovoltaic sources of energy which point out the segments of urban areas jeopardized by the possible appearance of microorganisms. Afterward, a review of laser techniques for the detection, identification, and destruction of such microorganisms was given. It was concluded where to direct the further laser system development to protect smart buildings from biological contamination.

Recycled concrete aggregate (RCA), obtained by crushing of original (old) concrete, consists of natural aggregate grains and a cement mortar matrix. The presence of old adhered cement mortar, which has higher porosity than natural aggregate, causes unfavourable properties of RCA. The research conducted in order to improve the quality of RCA and to enable its greater application in the construction industry is presented in this paper. Therefore, RCA was subjected to quality improvement treatments with hydrochloric acid and carbon dioxide (accelerated carbonation). The first procedure was aimed at partially removing the adhered cement mortar and the second at reinforcing the cement matrix. The physical, mechanical and chemical properties of all three types of RCA were tested. After the pre-soaking acid treatment (0.1 mol/dm3 HCl), RCA showed reduced water absorption (up to 3%); the process of accelerated carbonation also led to reduced water absorption (13–20%) as well as to improved mechanical properties (∼10%). A scanning electron microscopy investigation revealed that the carbonation process, as expected, significantly reduces porosity of RCA. The overall results show that if RCA is obtained by crushing of compact, high- -quality concrete, the procedures of aggregate quality improvement are not necessary.

By its technology, Self-Compacting Concrete does not need compaction by vibration. Compaction of this concrete, in every part, or in every corner of the formwork, including its hardly available parts, is done without any external forces except its own weight. These properties are achieved by adding superplasticizers, commonly with new Viscosity Modification Admixtures, or/and determined amount of powders. It is possible to use different mineral additions, where the use of those which are industrial by - products (like fly ash) has multiple environmental benefits. Lack of natural aggregate in urban areas and increasing distance between deposits of high - quality natural aggregate and building sites, forced building contractors to analyze possibility of replacing of natural aggregate with recycled materials (masonry, slag, concrete, etc.). On the other hand, huge amount of old concrete exists in urban areas and its removal and deposition is a big ecological problem. Aim of this paper is analysis of properties and technology of Self-Compacting Concrete with different mineral additions (lime, fly ash and silica fume), natural and recycled aggregate, considering mixes without recycled aggregate, with third recycled fraction, and with second and third recycled fractions.

The main reason for usage of crushed stone mineral aggregate is need for concrete construction building with care about environmental protection, water resources, etc. Influence of crushed stone mineral aggregate on concrete consistency is considered in this paper. River aggregate is used as a benchmark, and from crushed aggregates: limestone, andesite, diabase and basalt. The drawn conclusion is that fine crushed aggregate has an important influence on concrete consistency because it decreases concrete's workability and placing. Replacement with river aggregate improves concrete consistency. Coarse aggregate type also has an influence on consistency. Further investigations should be based on possibility of fine crushed aggregate usage for SCC production.

Self-compacting concrete is one of 'the most revolutionar development' in concrete research; this concrete is able to flow and to fill the most restacted places of the form work without vibration. There are several methods for testing it's properties in the fresh state: the most frequently used are slum-flow test, L-box and V-funnel. This work presents properties of self-compacting concrete, mixed with different types additives: fly ash, silica fume, hydraulic lime and a mixture of fly ash and hydraulic lime.

Although titanium and its alloys are widely used as dental implants, they cannot induce the formation of new bone around the implant, which is a basis for the functional integrity and long-term stability of implants. This study focused on the functionalization of the titanium/titanium oxide surface as the gold standard for dental implants, with electrospun composite fibers consisting of polyvinylpyrrolidone and Ca 2+ ions. Polymer fibers as carriers of Ca 2+ ions should gradually dissolve, releasing Ca 2+ ions into the environment of the implant when it is immersed in a model electrolyte of artificial saliva. Scanning electron microscopy, energy dispersive X-ray spectroscopy and attenuated total reflectance Fourier transform infrared spectroscopy confirmed the successful formation of a porous network of composite fibers on the titanium/titanium oxide surface. The mechanism of the formation of the composite fibers was investigated in detail by quantum chemical calculations at the density functional theory level based on the simulation of possible molecular interactions between Ca 2+ ions, polymer fibers and titanium substrate. During the 7-day immersion of the functionalized titanium in artificial saliva, the processes on the titanium/titanium oxide/composite fibers/artificial saliva interface were monitored by electrochemical impedance spectroscopy. It can be concluded from all the results that the composite fibers formed on titanium have application potential for the development of osteoinductive and thus more biocompatible dental implants.

The surface modification of dental implants plays an important role in establishing a successful interaction of the implant with the surrounding tissue, as the bioactivity and osseointegration properties are strongly dependent on the physicochemical properties of the implant surface. A surface coating with bioactive molecules that stimulate the formation of a mineral calcium phosphate (CaP) layer has a positive effect on the bone bonding process, as biomineralization is crucial for improving the osseointegration process and rapid bone ingrowth. In this work, the spontaneous deposition of calcium phosphate on the titanium surface covered with chemically stable and covalently bound alendronate molecules was investigated using an integrated experimental and theoretical approach. The initial nucleation of CaP was investigated using quantum chemical calculations at the density functional theory (DFT) level. Negative Gibbs free energies show a spontaneous nucleation of CaP on the biomolecule-covered titanium oxide surface. The deposition of calcium and phosphate ions on the alendronate-modified titanium oxide surface is governed by Ca 2+ -phosphonate (-PO 3 H) interactions and supported by hydrogen bonding between the phosphate group of CaP and the amino group of the alendronate molecule. The morphological and structural properties of CaP deposit were investigated using scanning electron microscopy, energy dispersive X-ray spectroscopy, X-ray diffraction and attenuated total reflectance Fourier transform infrared spectroscopy. This integrated experimental-theoretical study highlights the spontaneous formation of CaP on the alendronate-coated titanium surface, confirming the bioactivity ability of the alendronate coating. The results provide valuable guidance for the promising forthcoming advancements in the development of biomaterials and surface modification of dental implants.

The effects of various organic additives, such as diethanolamine (DEA) and ethanolamine (EA), and variations in aging times on the formation and stability mechanisms of spherical aggregates of ZnO nanoparticles (NPs) prepared by using solvothermal synthesis were studied. The experimental results of the structural, morphological and optical properties monitored by using X-ray diffraction, field-emission scanning electron microscopy (FE-SEM) and UV-Vis spectroscopy were supported by quantum chemical calculations at the level of density functional theory (DFT). Understanding the mechanism of spherical ZnO aggregate formation and its stability by mimicking the processes at the computer level was achieved through theoretical simulations of the ZnO surface/additive interactions using (ZnO) 36 -DEA and (ZnO) 36 -EA models. The fine-tuned spherical aggregation of ZnO nanoparticles was driven by various interactions, in particular, strong O-H∙∙∙O and weak N-H∙∙∙O hydrogen bonds as controlling interactions. The calculated negative free release energy, ∆G* INT , indicates that the ZnO surface/additive interaction in diethanolamine media is a spontaneous exergonic process (∆G* INT = -7.73 kcal mol -1 ), whereas, in ethanolamine media, it is an unfavorable, slightly endergonic process (∆G* INT > 0). The presence of two strong O-H∙∙∙O hydrogen bonds and, at the same time, a weaker N-H∙∙∙O hydrogen bond is the key factor for the very good and long-term aggregate stability of ZnO NPs in DEA media. This integrated experimental-theoretical study highlights the stability and compactness of spherical ZnO aggregates of ZnO NPs, prepared in the presence of diethanolamine compared to ethanolamine media, and provides a promising method and flexible design of ZnO nanomaterials to improve their adsorptive and optical properties.

The success of the osseointegration process depends on the surface characteristics and chemical composition of dental implants. Therefore, the titanium dental implant was functionalised with a composite coating of alendronate and hydrolysed collagen, which are molecules with a positive influence on the bone formation. The results of the quantum chemical calculations at the density functional theory level confirm a spontaneous formation of the composite coating on the titanium implant, ∆ G * INT = -8.25 kcal mol -1 . The combination of the results of X-ray photoelectron spectroscopy and quantum chemical calculations reveals the structure of the coating. The alendronate molecules dominate in the outer part, while collagen tripeptides prevail in the inner part of the coating. The electrochemical stability and resistivity of the implant modified with the composite coating in a contact with the saliva depend on the chemical nature of alendronate and collagen molecules, as well as their inter- and intramolecular interactions. The formed composite coating provides a 98% protection to the implant after the 7-day immersion in the artificial saliva. From an application point of view, the composite coating could effectively promote osseointegration and improve the implant's resistivity in contact with an aggressive environment such as saliva.

The potential to use waste glass, including cathode ray tube (CRT) glass, for making new products or as an admixture to existing ones is being intensively investigated. This kind of research intensified particularly in the period after CRT TV sets and computer monitors were replaced in the market by the advanced technology of thin film transistor (TFT) and liquid crystal display (LCD) screens. Cathode ray tube glass represents a considerable part of electronic waste (e-waste). E-waste globally increases at a far higher rate than other solid waste materials. There is a possibility to recycle cathode ray tube glass and use it in the construction industry. This paper shows the test results of physical and mechanical properties of blocks and paving flags. The reference specimen was made with quartz sand, while the other product employed a combination of quartz sand and ground panel cathode ray tube glass. The glass was ground to the fraction 0.25/1.00 mm, which corresponds to quartz sand fineness. The following tests were performed: shape and dimensions, resistance to freeze/thaw and de-icing salts, water absorption, splitting tensile strength and tensile strength by bending. Special attention was paid to the tests of Böhme wear resistance, slip resistance of the top surface of CRT products using a pendulum, radioactivity and leaching. The texture of the experimental concrete products was observed by SEM (scanning electron microscopy) and analyzed. The results obtained by experimental testing unequivocally show that CRT glass can successfully be used for making concrete blocks and paving flags.

The hydrothermal synthesis of zinc oxide (ZnO) particles from zinc acetylacetonate monohydrate in "pure" aqueous solution and in aqueous NaOH solution at 90 °C is reported. The structural and morphological properties of ZnO particles were investigated by powder X-ray diffraction, X-ray absorption spectroscopy (XAS), field emission scanning electron microscopy, and transmission electron microscopy. The effect of NaOH on the growth mechanism and photocatalytic performance of hierarchical ZnO structures was investigated. The experimental findings, supported by results of quantum chemical calculations at the level of density functional theory, were used to propose the mechanism of nucleation and preferential growth of finely tuned hollow and nonhollow ZnO structures and their effects on the photocatalytic activity. The calculations indicate that the process of ZnO nucleation in "pure" aqueous solution mainly proceeds by the reaction of small monomers, while tetramers play a crucial role in aqueous NaOH solution. Both the preferred ZnO nanostructure and microstructure growth processes are driven by O-H···O hydrogen bonds as controlling elements. The calculated values of the E O···H interaction indicate a stronger interaction via O-H···O hydrogen bonds in "pure" aqueous media ( E O···H = -11.73 kcal mol -1 ) compared to those obtained in aqueous NaOH solution ( E O···H = -8.41 kcal mol -1 ). The specific structural motif of the (ZnO-H 2 O) 12 dodecamers with calculated negative Δ G * INT free release energy indicates that the formation of anisotropic nanocrystalline ZnO with the c -axis as the primary growth direction is spontaneous and accelerated exclusively in "pure" aqueous solution, whereas it is an unfavorable endergonic process in aqueous NaOH solution (Δ G * INT > 0). Efforts have been made to determine the photocatalytic efficiency of the ZnO samples based on the XAS measurements. ZnO particles obtained in "pure" aqueous solution show the highest photocatalytic activity due to the presence of a larger amount of oxygen vacancies.

Quinolino[7,8- h ]quinoline is a superbasic compound, with a p K aH in acetonitrile greater than that of 1,8-bis(dimethylaminonaphthalene) (DMAN), although its synthesis and the synthesis of its derivatives can be problematic. The use of halogen derivatives 4,9-dichloroquinolino[7,8- h ]quinoline ( 16 ) and 4,9-dibromoquinolino[7,8- h ]quinoline ( 17 ) as precursors has granted the formation of a range of substituted quinolinoquinolines. The basicity and other properties of quinolinoquinolines can be modified by the inclusion of suitable functionalities. The experimentally obtained p K aH values of quinolino[7,8- h ]quinoline derivatives show that N 4 , N 4 , N 9 , N 9 -tetraethylquinolino[7,8- h ]quinoline-4,9-diamine ( 26 ) is more superbasic than quinolino[7,8- h ]quinoline. Computationally derived p K aH values of quinolinoquinolines functionalized with dimethylamino (NMe 2 ), 1,1,3,3-tetramethylguanidino (N═C(NMe 2 ) 2 ) or N , N , N ', N ', N ″, N ″-hexamethylphosphorimidic triamido (N═P(NMe 2 ) 3 ) groups are significantly greater than those of quinolino[7,8- h ]quinoline. Overall, electron-donating functionalities are observed to increase the basicity of the quinolinoquinoline moiety, while the substitution of electron-withdrawing groups lowers the basicity.

Organophosphorus compounds, like bisphosphonates, drugs for treatment and prevention of bone diseases, have been successfully applied in recent years as bioactive and osseoinductive coatings on dental implants. An integrated experimental-theoretical approach was utilized in this study to clarify the mechanism of bisphosphonate-based coating formation on dental implant surfaces. Experimental validation of the alendronate coating formation on the titanium dental implant surface was carried out by X-ray photoelectron spectroscopy and contact angle measurements. Detailed theoretical simulations of all probable molecular implant surface/alendronate interactions were performed employing quantum chemical calculations at the density functional theory level. The calculated Gibbs free energies of (TiO 2 ) 10 -alendronate interaction indicate a more spontaneous exergonic process when alendronate molecules interact directly with the titanium surface via two strong bonds, Ti-N and Ti-O, through simultaneous participation common to both phosphonate and amine branches. Additionally, the stability of the alendronate-modified implant during 7 day-immersion in a simulated saliva solution has been investigated by using electrochemical impedance spectroscopy. The alendronate coating was stable during immersion in the artificial saliva solution and acted as an additional barrier on the implant with overall resistivity, R ~ 5.9 MΩ cm 2 .

Image segmentation is one of the most important tasks in medical image analysis and is often the first and the most critical step in many clinical applications. In brain MRI analysis, image segmentation is commonly used for measuring and visualizing the brain's anatomical structures, for analyzing brain changes, for delineating pathological regions, and for surgical planning and image-guided interventions. In the last few decades, various segmentation techniques of different accuracy and degree of complexity have been developed and reported in the literature. In this paper we review the most popular methods commonly used for brain MRI segmentation. We highlight differences between them and discuss their capabilities, advantages, and limitations. To address the complexity and challenges of the brain MRI segmentation problem, we first introduce the basic concepts of image segmentation. Then, we explain different MRI preprocessing steps including image registration, bias field correction, and removal of nonbrain tissue. Finally, after reviewing different brain MRI segmentation methods, we discuss the validation problem in brain MRI segmentation.

DFT calculations revealed that 1,8-diazanaphthalene di-N-oxides provide extraordinary oxygen superbases, whose gas-phase and acetonitrile basicities surpass those of classical naphthalene-based nitrogen proton sponges. Such high basicity is almost entirely a consequence of a large strain-induced destabilization in neutral forms, while only a small contribution is offered by the intramolecular [O-H···O](-) hydrogen bonding upon protonation.

Focal cortical dysplasia (FCD) is a frequent cause of epilepsy and can be detected using brain magnetic resonance imaging (MRI). One important MRI feature of FCD lesions is the blurring of the gray-white matter boundary (GWB), previously modelled by the gradient strength. However, in the absence of additional FCD descriptors, current gradient-based methods may yield false positives. Moreover, they do not explicitly quantify the level of blur which prevents from using them directly in the process of automated FCD detection. To improve the detection of FCD lesions displaying blur, we develop a novel algorithm called iterating local searches on neighborhood (ILSN). The novelty is that it measures the width of the blurry region rather than the gradient strength. The performance of our method is compared with the gradient magnitude method using precision and recall measures. The experimental results, tested on MRI data of 8 real FCD patients, indicate that our method has higher ability to correctly identify the FCD blurring than the gradient method.

Developing a realistic volume conductor head model is an important step towards a non-invasive investigation of neuro-electrical activity in the brain. For adults, different volume conductor head models have been designed and successfully used for electroencephalography (EEG) source analysis. However, creating appropriate neonatal volume conductor head model for EEG source analysis is a challenging task mainly due to insufficient knowledge of head tissue conductivities and complex anatomy of the developing newborn brain. In this work, we present a pipeline for modeling a realistic volume conductor model of the neonatal head, where we address the modeling challenges and propose our solutions. We also discuss the use of our realistic volume conductor head model for neonatal EEG source analysis.

In patients with intractable epilepsy, focal cortical dysplasia (FCD) is the most frequent malformation of cortical development. Identification of subtle FCD lesions using brain MRI scans is very often based on the cortical thickness measurement, where brain cortex segmentation is required as a preprocessing step. However, the accuracy of the selected segmentation method can highly affect the final FCD lesion detection. In this work, we propose an improved graph cuts algorithm integrating Markov random field-based energy function for more accurate brain cortex MRI segmentation. Our method uses three-label graph cuts and preforms automatic 3D MRI brain cortex segmentation integrating intensity and boundary information. The performance of the method is tested on both simulated MR brain images with different noise levels and real patients with FCD lesions. Experimental quantitative segmentation results showed that the proposed method is effective, robust to noise and achieves higher accuracy than other popular brain MRI segmentation methods. The qualitative validation, visually verified by a medical expert, showed that the FCD lesions were segmented well as a part of the cortex, indicating increased thickness and cortical deformation. The proposed technique can be successfully used in this, as well as in many other clinical applications.

The paper comprises 63 patients with diagnosed vasculitis of the skin who had abnormal findings in the urine. Thirteen of these patients had positive skin findings and abnormal findings in the urine, with concomitant attacks of dyspnea as seen in bronchial asthma. These patients account for 20% of the entire group, while there was an incidence of 37% of systemic manifestations. Skin findings: 45% had a maculopapular rash, 36% had urticarial findings, 13% had urticaria and angioedema and 6% had angioedema alone. Nonspecific biologic syndrome of evolution was statistically significant while no significant changes were found in the number of white blood cells and eosinophils. The degree of proteinuria ranged from 0.1 g/L to 1.16 g/L. Most patients with proteinuria above 0.25 g/L had microhematuria. Slightly over 50% of the patients had signs of complement activation by the alternative pathway, along with the presence of cryoglobulins. Increased histamine in the serum was found in over 50% of the patients although the values of histamine did not correlate with the degree of proteinuria. Proteinuria was not detected in patients with very high values of histamine (and without signs of vasculitis), which indicates that histamine itself responsible for changes in the glomeruli. There is a possibility that local tissue hyperhistaminemia is responsible for the increased permeability of the basal membrane of the glomeruli. According to the obtained results, the etiology of proteinuria and microhematuria should be pursued in the pathogenesis of vasculitis as signs of complement activation indicate. Other possible causes for proteinuria were excluded. The proteinuria was selective, benign according to its course and degree, occurred concomitantly with skin findings and was absent during remission of the disease.