On the Development of New Forensic Tools for Detection of Human Skin Prints

The article reviews the main physical and physicochemical factors influencing the three-component system “fingerprint powder – prints bearing surface – sweat and grease print substance”. The authors propose new model compositions of fingerprint powders considering the reviewed common patterns: non-magnetic and luminescent magnetic. The features of prints bearing surfaces and developed fingerprint powders have been evaluated by applying electronic microscopy methods (scanning and probe microscopy). The authors have proven that the use of nano- and ultra disperse materials in the developed compositions (carbon nanotubes and shungite) enables to vary the sorption and adhesive capacity of fingerprint powders, which allows detecting fingerprints on varying surfaces with high selectivity toward the sweat and grease print substance and contrasting effect.

WHEAT ANDROCLINIC CALLI: DATA OF SCANNING ELECTRONIC MICROSCOPY

The processes of formation different types of calli, as well as the morphogenesis pathways in morphogenic calli, were studied by scanning electron microscopy (SEM) during anther culture in vitro in hybrid line Fotos of spring soft wheat. The microspore haploid origin of calli has been proven. The morphological status of the obtained calli was determined. It was shown that morphogenic callus consists of small densely packed meristematic cells covered with extracellular substance. This type of calli was obtained using a variant of the Potato II induction culture medium, added by 1.0 mg/l synthetic auxin 2,4-D. Nonmorphogenic callus consists of large, elongated, loosely located cells with a smooth surface. This type of calli was obtained using a variant of the Potato II culture medium, added by 2.0 mg/l 2,4-D. It was found that the introduction of various IAA concentrations into the Blaydes nutrient medium for regeneration in morphogenic calli implements the following pathways of morphogenesis in vitro: embryoidogenesis (without IAA addition), gemmorhizogenesis (0.5 mg/l), and rhizogenesis (1.5 mg/l). Revealed degenerative changes in cells of nonmorphogenic calli. The fundamental possibility of regulating of the morphogenesis pathways of in vitro of morphogenic calli in the direction necessary for research in biotechnological research has been confirmed.

Efficacy of slightly acidic electrolyzed water on inactivation of Cronobacter sakazakii and biofilm cell

The disinfection efficacy and mechanism of slightly acid electrolyzed water (SAEW) on Cronobacter sakazakii were investigated. SAEW solutions in three concentrations were carried on C. sakazakii which decreased in a range of 23%-55% in 2 minutes. The propidium iodide (PI) uptake and electronic microscopy (SEM) images indicated that SAEW treatment damaged cell integrity and changed membrane permeability with leaking nucleic acid (109.7%), intercellular protein (692.3%) and K + (53.6%). It was accompanied with lower ability of biofilm formation. SAEW treatment reduced the activity of SOD and CAT from 100.73 U/mgprot and 114.18 U/mgprot to 50.03 U/mgprot and 50.13 U/mgprot, respectively. It lowered down the gene expression of response regulator (katG, rpoS, phoP, glpK,dacC and CSK29544_RS05515 ) which made C. sakazakii failed to repair osmotic stress-induced damage and inhibited their biofilm formation. These findings provide an understanding of associations between bacterial genotype and phenotype induced by SAEW.

Morphology of metallic foams synthetized by plasma electrolysis deposition

The aim of our work is to understand the mechanism governing the growth of metallic foams synthetized by plasma electrolysis deposition. This paper reports the influence of the applied voltage on the morphology and microstructure of copper and gold foams. The evolution of strands morphology and size is investigated by field emission scanning electronic microscopy (FE-SEM). The role of the voltage in the growth of metallic foams is then discussed. Finally, the crystalline structure of the strands is determined by transmission electronic microscopy (TEM) and selected area electron diffraction.

Synthesize and Characterize Dibutyltin(IV) Oxide Complex by Utilizing New Ligand

Herein successfully synthesized new organotin(IV) complexBu2SnOL by reacting sulfamethoxazole drug as a ligand with dibutyltin (IV) oxide. The synthesized complex was fully characterized by Fourier transform infrared, 1proton nuclear magnetic resonance, 13carbon nuclear magnetic resonance, 119tin nuclear magnetic resonance and ultraviolet-visible spectroscopies. Field emission scanning electronic microscopy was also applied to study the surface morphology of synthesized complex. The above techniques have demonstrated that the complex was prepared with high percentage of purity. This type of compound has various applications in medicine and industry. For example, using it as photo–stabilizer of different plastic polymers (polyvinyl chloride, polystyrene and polyvinyl alcohol).

Cryptic subterranean diversity in Collembola indicates that Hot Spot in ferruginous rock may have serious implications in Brazilian conservation policy.

A super diverse hot spot of subterranean Collembola in ferruginous rock caves and Mesovoid Shallow Substratum is revealed by the analysis of cryptic diversity. The diversity is accessed by detailed description of chaetotaxy and slight variation in morphology of 11 new species of Trogolaphysa Mills, 1938 (Collembola, Paronellidae, Paronellinae) and the 49 previously recorded species of springtails from caves, using optical and electronic microscopy. When combined with recent subterranean surveys, our results show an important reservoir of cave diversity in the Mesovoid Shallow Substratum, contrasting with the conservation policy for subterranean fauna in metallogenic areas in Brazil which prioritizes the caves instead the cave species, which may be extremely detrimental to the fauna in the shallow subterranean habitats not accessible to humans.

Ag-TiO2 Nanocomposites: visible or solar light driven plasmonic photocatalysis?

Background: The demand for photocatalytic processes assisted by solar radiation has stimulated the upgrading of established systems, as the semiconductor modification with noble metals. Objective: the synthesis, characterization, and photocatalytic activity evaluation of the Ag-TiO2, against sulfamethoxazole molecule, and investigate the significance of the plasmonic phenomenon in Visible (450 - 1000nm) and UV-Vis (315-800 nm) radiation. Methods: Different nanocomposites Ag/TiO2 ratios were synthesized by the deposition of Ag nanoparticles on the TiO2 surface by in-situ photoreduction, and then calcinated at 400°C for 2 hr. The chemical-physical properties of the materials were examined by UV-Vis Diffuse Reflectance (UV-Vis DRS) Scanning Electronic Microscopy (SEM), Transmission Electronic Microscopy (TEM), X-Ray Energy Dispersive Spectroscopy (EDS). The experiments were conducted in a cooled photochemical reactor irradiated by halogen lamp (250W). The degradation of Sulfamethoxazole was monitored by HPLC-DAD. Results: Although the prepared photocatalysts show an intense plasmonic band centered at 500 nm, no photocatalytic activity was observed in the process assisted by artificial visible radiation ( ≥ 450 nm). In processes assisted by artificial UV-Vis radiation, the photolysis rate of the model compound (sulfamethoxazole) was higher than the photocatalytic rate, and in the absence of UV radiation, all the reactions were inhibited. The positive effect of the presence of silver nanoparticles onto the TiO2 surface was only evidenced in studies involving solar radiation. Conclusion: The results suggest the need for a balance between UV and Vis radiation to activate the nanocomposite and perform the sulfamethoxazole degradation.

Strongly Adhesive and Antimicrobial Peptide-Loaded, Alginate–Catechol-Based Gels for Application against Periimplantitis

Background: Periimplantitis is a disease linked to oral virulent bacteria such as P. gingivalis that grow in dental implants surrounding tissues and between implants and abutments. Antimicrobial gels previously described to fill these sites lose their effectiveness and resorb over time. Objective: Characterization of biophysical and antimicrobial properties of an original hydrogel, Alginate–Catechol (Alg–Cat), combined to D-Cateslytin (D-CTL). Methods: Gelation kinetics, frequency and strain sweep measurements were performed by rheology. Antibacterial activity of the gels was tested against P. gingivalis, and the MIC was determined. Peptides released from the gels were purified by HPLC and characterized by MALDI–TOF mass spectrometry. The behavior of bacteria in contact with the gel was observed using optical and electronic microscopy (SEM and TEM). Results: Gelation was fast and was achieved in 2 min with a storage modulus between 25 and 30 Pa. The gels were stable under strain and showed an adhesive potential reinforced with aging at 18 h (5.4 kPa) under a slow retraction speed (4 J·m−2 at 10 µm/s) with a mixed rupture profile (adhesive/cohesive). The MIC of D-CTL inside the Alg–Cat gel against P. gingivalis was equal to 470 µg·mL−1 after 24 h. Peptides recovered in the supernatant and inside the gel were fragmented, most of them conserving the ⍺-helix active site. No bacteria were visualized at the surface and inside the gel after 24 h. This gel is promising for clinical application for the prevention of periimplantitis.

Methods and Products for the Conservation of Vandalized Urban Art Murals

The possibility of contemporary mural paintings to be “tagged” by vandals, with spray and/or markers, represents a serious problem for the conservation of urban art. The present study aims to define the applicability of a protective coating on murals’ surface to preserve them against vandalism. The research has been focused on anti-graffiti products currently used in the field of cultural heritage conservation. These products represent an optimum start point to preserve mural artwork from vandal actions. The commercially available anti-graffiti products have been compared with an innovative product, PRO-ART, specifically formulated by YOCOCU in collaboration with Pelicoat, for the conservation of murals. At the same time, it has tested the cleaning of contemporary murals by using different mixtures of solvents and surfactants. The experimentations have been carried out on external walls, followed by the conducting of in situ tests (application tests, empirical evaluations and colorimetric analysis), as well as laboratory investigations (contact angle and optical/electronic microscopy).

Coatings Based on Phosphate Cements for Fire Protection of Steel Structures

Fire events in buildings can cause losses to human life and important material damage, therefore a great deal of attention is paid nowadays to fire prevention. Buildings based on steel structures are especially affected in the event of a fire, due to the important loss of load-bearing capability when steel is heated at temperatures higher than 500 °C. Therefore, one possible method to mitigate the deleterious effect of fire is to protect steel structures from direct heating by applying protective coatings. In this paper, the ability of magnesium phosphate cement (MPC), based on dead burned magnesite and calcium magnesium phosphate cement (CMPC) coatings, to protect a steel substrate was assessed. CMPCs were obtained by mixing partially calcined dolomite with a KH2PO4 (MKP) solution, and in some cases, with a setting retarder (borax). The main mineralogical compounds assessed by X-ray diffraction and electronic microscopy (SEM-EDS) in CMPC are MgO, CaCO3, and K-struvite (KMgPO4·6H2O). The coatings based on MPC and CMPC, applied to steel plates, were tested in direct contact with a flame; the coatings of MPC and CMPC without the borax addition prevented the temperature increase of a metal substrate above 500 °C. No exfoliation of coatings (MPC and CMPC without borax addition) was noticed during the entire period of the test (45 min).