In this paper, we report on the first experimental study on the impact of neutron radiation on quasi-free-standing (QFS) graphene. For this purpose, we have fabricated hydrogen-intercalated QFS ...graphene on semiinsulating high-purity 4H-SiC(0001), passivated it with an Al2O3 layer, and exposed it to a fast-neutron fluence of ≈6.6×1017 cm−2. The results have shown that the graphene sheet is only moderately affected by the neutron radiation with the estimated defect density of ≈4×1010 cm−2. The low structural damage allowed the Al2O3/graphene/SiC system to maintain its electrical properties and an excellent sensitivity to magnetic fields characteristic of QFS graphene. Consequently, our findings suggest that the system may be a promising platform for magnetic diagnostics in magnetic-confinement fusion reactors. However, the scope of its use should be a subject of further study. In this context, we have explored possible modes of damage and have concluded that the main factor that affects the electrical parameters of the structure is the impact of neutrons on the layer of hydrogen atoms saturating the SiC(0001) surface. We have shown, employing density functional theory (DFT) computations, that damage to the intercalating layer could lower hole concentration in graphene via reduced charge polarization and local coupling on the interface.
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•Quasi-free-standing properties of graphene persist after neutron irradiation.•Post-radiation damage to the H intercalation lowers the carrier density in graphene.•A degree of self-healing in the system via surface diffusion of hydrogen.•Temperature above 200 °C facilitates the reconstruction of damaged H intercalation.
Physical wounds in fish can devastate bodily homeostasis, increase the likelihood of secondary infections, and cause massive economic damage. Due to the importance of skin as a primary physical ...barrier, the strategy of promptly healing physical wounds to reduce further negative consequences has attracted a great deal of attention. The purpose of this study was to accelerate physical wound healing in the flounder using LED technology, which can be applied to thousands of fish at the same time at a reasonable economic cost. The fish epithelial cell line (Epithelioma papulosum cyprini; EPC) was used to verify the proliferative effects of LED irradiation at wavelengths of 465, 520, and 640 nm at 0, 10, 20, 40, and 80 μ·mol·m−2·s−1. Also, desquamated wounds were made to flounder with a razor, and the wounds were exposed to LED light at 520 and 640 nm, as well as ambient light as a control, in 12-h light/ dark cycles for seven or 28 days. The results showed that 520 and 640 nm LED treatment stimulated EPC cell proliferation, while the no-LED and 465 nm LED conditions had no effect. After the injuries, the mortality rate of fish exposed to 520 nm LED was markedly lower than those of the control (ambient light) and 640 nm-treated group. Also, the highest re-generated epithelium thickness (1-day post-injury (dpi)) and thicker collagen and connective tissue (7 dpi) were observed in the 520 nm group, along with high expression of IL-1, HSP70, TNF-α, and MMP-13. Likewise, significantly faster wound closure rates were observed with ample recovered muscle layers in the 520 nm treatment group at 21 and 28 dpi. These results show that 520 nm LED treatment is a very effective alternative method of aiding recovery from physical injuries, and is an eco-friendly method that can easily be applied in aquaculture.
•The specific wavelength of LEDs (green; 520 nm and red; 640 nm) can stimulate the replication of fish epithelial cells (Epithelioma papulosum cyprini).•The wounded fish under green LED showedthe prompt re-epithelization and re-construction of connective tissue with reducing mortality.•The green LEDs exposures could activate gene expression relevant to immune responses and wound recovery on the wound site.
This review aims to analyze Mentha piperita L. as a potential raw material for the development of new health-promoting products (nutraceuticals, cosmetics, and pharmaceutical products). A lot of ...scientific publications were retrieved from the Scopus, PubMed, and Google Scholar databases which enable the study and generalization of the extraction procedures, key biologically active compounds of essential oil and extracts, biological properties, and therapeutic potential of M. piperita, along with perspectives on the development of its dosage forms, including combinations of synthetic active substances and herbal preparations of M. piperita. The results of this review indicate that M. piperita is a source rich in phytoconstituents of different chemical nature and can be regarded as a source of active substances to enhance health and to develop medicinal products for complementary therapy of various conditions, especially those related with oxidant stress, inflammation, and moderate infections. Essential oil has a broad spectrum of activities. Depending on the test and concentration, this essential oil has both anti- and prooxidant properties. Gram-positive bacteria are more sensitive to the essential oil of M. piperita than Gram-negative ones. This review also considered some facets of the standardization of essential oil and extracts of M. piperita. Among the identified phenolics of extracts were caffeic acid, rosmarinic acid, eriocitrin, luteolin derivates (luteolin-7-O-rutinoside, luteolin-7-O-glucoronide), and hesperidin. The concentration of these phenolics depends on the solvent used. This review also considered the relationships between the chemical component and biological activity. The results showed that the essential oil and extracts reduced inflammation in vitro by inhibiting the production of pro-inflammatory cytokines, such as tumor necrosis factor-alpha (TNF-α) and interleukin-6 (IL-6), and in vivo by reducing the paw edema induced using carrageenan injection in rats. Therefore, herbal preparations of M. piperita are promising medicinal and cosmetic preparations for their usage in skincare and oral cavity care products with antimicrobial, anti-inflammatory, and wound-healing properties. This plant can also be regarded as a platform for the development of antibacterial preparations and combined anti-inflammatory and cardioprotective medicinal products (synthetic active substances plus herbal preparations). This review could be considered for the justification of the composition of some medicinal products during their pharmaceutical development for writing a registration dossier in the format of Common Technical Document.
This paper presented an effective approach for electroplating of coatings on the activated surface of pure Ti substrate using pulsed electro deposition. Regarding the ceramic-like TiO2 barrier layer ...on its surface of Ti substrate to inhibit surface activity, a novel activating solution that composed of HF, HCl, Ce(NO3)2, TiCl3, and bal. DMF dissolvent was applied for surface modifications of Ti substrate in order to increase interfacial bonding strength of surface Ni coatings. Besides a comparative study of Ni nanocrystalline coatings without and with CeO2 addition was carried out for disclosing the role of the Ce-rich phase on managing microstructure and high-temperature oxidation resistance during oxidation at 800 or 1000°C. Results indicated that Ce-rich precipitations, where dispersed along grain boundaries (GBs), were favorable for completing the spalling oxide-layers on Ni-CeO2 nanocomposite coatings during oxidation at 800°C. Furthermore, an analytical modeling was validated for better understanding of Ce-rich precipitations along GBs defects for monitoring oxidation mechanisms. Furthermore, this finding would be therefore leading to the guidelines for Ce-rich precipitations on the strengthening of Ni-based superalloys.
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•Well-dispersed CeO2 compounds along GBs were favorable for structural densifications of nanocrystalline Ni coatings.•Improved oxidation resistance of Ni-CeO2 nanocomposite coatings was attributed to the Ce-rich phase in NiO oxide scales.•An analytical modeling was validated for the Ce-rich precipitations to make self-healing effects on completing GBs defects.
► Healing process monitored with Raman spectroscopy. ► Healing of osteonecrotic femoral head. ► BPC 157 treatment. ► Statistical analysis of recorded spectra. ► Student t-test and principal component ...analysis.
The healing effect of BPC 157 on rat femoral head osteonecrosis was monitored by Raman spectroscopy. Three groups of rats were defined: an injured group treated with BPC 157 (10μg/kg/daily ip), an injured control group (treated with saline, 5ml/kg/daily ip), and an uninjured healthy group. The spectra were recorded and the healing effect assessed on samples harvested from animals which were sacrificed 3 and 6weeks after being injured. The statistical analysis of the recorded spectra showed statistical differences between the BPC 157-treated, control, and healthy groups of animals. In particular, after 6weeks the spectral resemblance between the healthy and BPC 157 samples indicated a positive BPC 157 influence on the healing process of rat femoral head.
An ultraviolet shielding hydrogel of P(NaSS-co-MPTC)/TiO
2
was prepared by introducing TiO
2
nanoparticles (TiO
2
NPS) into polyampholyte matrix through photo-initiated radical copolymerization of ...cationic monomer of 3-(methacrylamide) propyltrimethylammonium chloride (MPTC) and anionic monomer of sodium 4-vinylbenzenesulfonate (NaSS) in the aqueous solution of sodium chloride (NaCl). FTIR, XPS, TEM, XRD, and SEM were used to characterize the morphology and structure of hydrogel of P(NaSS-co-MPTC)/TiO
2.
The result showed that anatase TiO
2
NPS with the size about 15 ~ 20 nm were not just acted as ultraviolet shielding agent and general photo-initiator, they also could be crosslinked in polyampholyte matrix by hydrogen bonding between hydroxyl groups on the surface of TiO
2
NPS and sulfonate groups on the polymer chains. Based on two kinds of reversible weak bonds of hydrogen bond and ionic bond, the P(NaSS-co-MPTC)/TiO
2
hydrogel exhibited excellent mechanical properties and self-healing ability at ambient conditions, which will greatly increase its service life being a UV inhibitor.
The aim of this study is to introduce natural-based polymers, chitosan and starch, to design a remedial nanocomposite, comprising of cerium oxide nanoparticles and silver nanoparticles, to ...investigate their effects in accelerating wound healing and in wound microbial load. Cerium oxide nanoparticles synthesized in starch solution added to the colloidal dispersion of synthesized silver nanoparticles in chitosan to make a three-component nanomaterial. Mice were anaesthetized and two parallel full-thickness round wounds were excised under aseptic conditions with the help of sterile dermal biopsy punch. Furthermore, effects of silver-chitosan and silver-cerium-chitosan nanocomposite had evaluated on rate of wound closure and collagen density and on microbial load of wound in full-thickness model. Results showed that both silver chitosan and silver-cerium-chitosan had significant impact on acceleration of wound closure and collagen content and on reduction of wound microbial load in comparison with control group, which was, received no treatments. However, the silver-cerium-chitosan nanocomposite is more potent than silver-chitosan group and control group in wound closure. The wound healing effects of silver-cerium-chitosan nanocomposite are due to unique features of its three components and this nanocomposite promises impressive remedies for clinical application.
Conducting a biographical-narrative interview is already a kind of psychological intervention. In this article, I will reflect on this. I will introduce the narrative-interviewing method and discuss ...the following: What processes are prompted for narrators when they tell their life story and for the interviewer guiding the conversation in a narrativebiographical style? What are the chances offered by this method of directing a conversation for setting off initial healing processes, and what are the risks and dangers involved? These questions are pursued, in particular, in the context of research interviews— especially in the context of my interviews with survivors of the Shoah and their children and grandchildren—but also in the context of counseling. I will also discuss the method’s limits in conversations with people experiencing acute life crises.
Background. The issues wound-healing is relevant to the present. Wound-healing is a complex process which involves the accumulation of fibroblasts in the dermal damage zone, the synthesis of ...scleroproteins, wound retraction, epithelization. A promising direction of research is the creation of application prolonged dosage forms of transdermal appointment based on synthetic polymers and natural origin. At this point, a natural polymer collagen can be considered the most promising raw material in the development of such drugs for topical use. It should be noted that immobilization of known drugs and biologically active agents on collagen provides prolongation of their action, reduces toxicity, reduces local irritant reaction, increases therapeutic activity. Probiotics as a new class of therapeutic and prophylactic drugs are now increasingly used in medical practice and indications for their use are increasingly expanding and represent a heterogeneous group of non-pathogenic bacteria. As noted above, a significant place in the infectious pathology of people occupy purulent-inflammatory diseases of the skin and mucous membranes, which often develop as a result of their traumatic injuries (wounds, burns). Treatment of such injuries with antibiotics and other traditional means is not always effective, so the task of combating inflammatory diseases of the external cover is currently relevant and requires new solutions. This circumstance served as the basis for theoretical and experimental studies to assess the possibility of developing new pharmacological preparations for external use on the basis of already known probiotics and modern transdermal bases. Methods. The article presents the results of studies of the wound-healing effect of collagen membranes with probiotics. Toxicological studies were performed to test of membrane toxicity studies on white mice and test of studying the local irritant effect on mucous membraneson rabbits. The wound-healing effect of membranes was studied on Guinea pigs based on the model of conditionally pure wounds. Results and discussion. In the application ofcollagen membranes did not observe the death of animals throughout the experience. The general condition of animals, which exposed to chronic membrane exposure did not differ from the control animals. Skin of experimental and control animals had the same manner, signs of irritation in all groups were absent. The significant physiological differences between control and experimental groups of animals were not found. The weight coefficients of internal organs also did not differ from the control. The autopsy did not reveal any abnormalities in the structure of organs and of serous membranes. Microscopic studies have shown no fundamental differences between experience and control. Conclusion. Biomembranes with probiotics have a pronounced wound-healing effect, and are characterized by complete epithelization of the burn defect and a shrinking in the time of healing.
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