Influence of wide band gap oxide substrates on the photoelectrochemical properties and structural disorder of CdS nanoparticles grown by the successive ionic layer adsorption and reaction (SILAR) method

The photoelectrochemical properties of nanoheterostructures based on the wide band gap oxide substrates (ZnO, TiO2, In2O3) and CdS nanoparticles deposited by the successive ionic layer adsorption and reaction (SILAR) method have been studied as a function of the CdS deposition cycle number (N). The incident photon-to-current conversion efficiency (IPCE) passes through a maximum with the increase of N, which is ascribed to the competition between the increase in optical absorption and photocarrier recombination. The maximal IPCE values for the In2O3/CdS and ZnO/CdS heterostructures are attained at N ≈ 20, whereas for TiO2/CdS, the appropriate N value is an order of magnitude higher. The photocurrent and Raman spectroscopy studies of CdS nanoparticles revealed the occurrence of the quantum confinement effect, demonstrating the most rapid weakening with the increase of N in ZnO/CdS heterostructures. The structural disorder of CdS nanoparticles was characterized by the Urbach energy (EU), spectral width of the CdS longitudinal optical (LO) phonon band and the relative intensity of the surface optical (SO) phonon band in the Raman spectra. Maximal values of EU (100–120 meV) correspond to СdS nanoparticles on a In2O3 surface, correlating with the fact that the CdS LO band spectral width and intensity ratio for the CdS SO and LO bands are maximal for In2O3/CdS films. A notable variation in the degree of disorder of CdS nanoparticles is observed only in the initial stages of CdS growth (several tens of deposition cycles), indicating the preservation of the nanocrystalline state of CdS over a wide range of SILAR cycles

Raman Study of CVD Graphene Irradiated by Swift Heavy Ions

CVD-graphene on silicon was irradiated by accelerated heavy ions (Xe, 160 MeV, fluence of 1011 cm-2) and characterized by Raman spectroscopy. The defectiveness of pristine graphene was found to be dominated by grain boundaries while after irradiation it was determined by both grain boundaries and vacancies. Respectively, average inter-defect distance decreased from ~ 24 to ~ 13 nm. Calculations showed that the ion irradiation resulted in a decrease in charge carrier mobility from ~ 4.0 × 103 to ~ 1.3·103 cm2/V s. The results of the present study can be used to control graphene structure, especially vacancies concentration, and charge carrier mobility

Micro Raman investigation of graphene synthesized by atmospheric pressure CVD on copper foil from decane

In this article we present the results of micro-Raman studies of graphene grown on copper foil surface by atmospheric pressure CVD using decane as precursor, nitrogen as carrier gas with zero flow of hydrogen. Analysis of Raman spectroscopy data showed that film contains spots with single layer thick graphene. We observed significant blue shift of 2D and G bands positions for mono-atomically thick graphene on copper foil. Following literature we relate this shift to the strain induced by the presence of copper substrate. Moreover, we observed changes in the defectiveness of graphene layers after the transfer, which was related to the appearance of chemically-induced defects and defects induced by changes in the mechanical strain

The Opportunity of Using Diode Laser with the Length of 1940 nm in the Treatment of Hemorrhoids

Aim: to improve the results of treatment of patients with hemorrhoidal disease of the 2nd and 3rd stages by using a diode laser with a wavelength of 1940 nm.Materials and methods. The study included 28 patients with hemorrhoids of the second or third stage. A new treatment method based on the use of a diode laser with a wavelength of 1940 nm was applied to all patients. This technique (laser hemorrhoidoplasty) provides for the thermal effect of laser radiation on the cavernous tissue of the internal hemorrhoid node and the terminal branches of the upper rectal artery. The intensity of postoperative pain syndrome was assessed and the clinical symptoms of hemorrhoidal disease manifestations were studied before and after surgery. To study the effectiveness of the proposed method and to assess the depth of thermal exposure to laser radiation, transrectal ultrasound with Dopplerography and pathomorphological examination were performed. The functional state of the rectal locking apparatus before surgery and in the postoperative period was assessed using sphincterometry. The quality of life of patients who underwent laser hemorrhoidoplasty was studied according to the SF 36 questionnaire.Results. Surgical intervention was performed under both local and spinal anesthesia. Intraoperative complications in the form of hemorrhoidal node bleeding were noted in 3 patients. In the early postoperative period, inflammatory edema of external hemorrhoids was diagnosed in 4 patients. The intensity of the pain syndrome was assessed on the VAS scale and by day 7 in 93 % of patients it did not exceed 1 point. All 28 patients were followed up within 1 to 6 months after the operation. All had no complaints characteristic of hemorrhoidal disease, no relapse of the disease was detected in any observation. Transrectal ultrasound with Dopplerography was performed, which made it possible to diagnose a 2–3-fold decrease in blood flow along the terminal branches of the upper rectal artery, and internal hemorrhoids determined earlier, before surgery, were not visualized already 1 month after surgery. According to sphincterometry, no violations of anal retention function were detected in all 28 patients.Conclusion. Surgical treatment of hemorrhoids of the 2nd and 3rd stages with the use of a diode laser with a wavelength of 1940 nm. with proper technical performance and the choice of optimal energy, it allows to achieve a good clinical effect. The proposed method of intervention ensures the absence of a pronounced pain syndrome, which does not lead to a significant decrease in the quality of life already in the early postoperative period and allows to shorten the period of labor rehabilitation. Laser hemorrhoidoplasty is a highly effective method of treating hemorrhoids at stages 2 and 3 of the disease and opens up the possibility of treatment on an outpatient basis

Differential Carbohydrate Recognition by Campylobacter jejuni Strain 11168: Influences of Temperature and Growth Conditions

The pathogenic clinical strain NCTC11168 was the first Campylobacter jejuni strain to be sequenced and has been a widely used laboratory model for studying C. jejuni pathogenesis. However, continuous passaging of C. jejuni NCTC11168 has been shown to dramatically affect its colonisation potential. Glycan array analysis was performed on C. jejuni NCTC11168 using the frequently passaged, non-colonising, genome sequenced (11168-GS) and the infrequently passaged, original, virulent (11168-O) isolates grown or maintained under various conditions. Glycan structures recognised and bound by C. jejuni included terminal mannose, N-acetylneuraminic acid, galactose and fucose. Significantly, it was found that only when challenged with normal oxygen at room temperature did 11168-O consistently bind to sialic acid or terminal mannose structures, while 11168-GS bound these structures regardless of growth/maintenance conditions. Further, binding of un-capped galactose and fucosylated structures was significantly reduced when C. jejuni was maintained at 25°C under atmospheric oxygen conditions. These binding differences identified through glycan array analysis were confirmed by the ability of specific lectins to competitively inhibit the adherence of C. jejuni to a Caco-2 intestinal cell line. Our data suggests that the binding of mannose and/or N-acetylneuraminic acid may provide the initial interactions important for colonisation following environmental exposure

The Fluorescent Probing Method in the Estimation of the Functional Probabilities of the Blood Plasma Transport Systems

During this work method of fluorescent probes with differently charged fluorescent dyes was used for estimation of binding ability of the blood plasma main transport proteins. Investigations were done at the patients with liver cirrhosis for creating on those basis fluorescent tests adapted for clinical use. Such tests should use for depending of severity degree of pathological process and for the correct choice of the most effective haemosorbent for extracorporeal blood purification in the definite clinical situation. Regularity was shown for the changes in the binding ability of the blood plasma main transport proteins in liver cirrhosis, which depended on the stage of the disease and allowed efficiently estimate severity degree of pathological process. Comparative evaluation of the efficacy of different charcoal haemosorbents widely used in clinical practice as well as "Prometheus" device was done in terms of endogenous intoxication syndrome correction at liver cirrhosis patients using results of biochemical analysis and method of fluorescent dyes. It was shown that the most effective sorbents were sorbents of "Prometheus" and between charcoal heamosorbents - "Carbocol"

The Fluorescent Probing Method in the Estimation of the Functional Probabilities of the Blood Plasma Transport Systems

During this work method of fluorescent probes with differently charged fluorescent dyes was used for estimation of binding ability of the blood plasma main transport proteins. Investigations were done at the patients with liver cirrhosis for creating on those basis fluorescent tests adapted for clinical use. Such tests should use for depending of severity degree of pathological process and for the correct choice of the most effective haemosorbent for extracorporeal blood purification in the definite clinical situation. Regularity was shown for the changes in the binding ability of the blood plasma main transport proteins in liver cirrhosis, which depended on the stage of the disease and allowed efficiently estimate severity degree of pathological process. Comparative evaluation of the efficacy of different charcoal haemosorbents widely used in clinical practice as well as "Prometheus" device was done in terms of endogenous intoxication syndrome correction at liver cirrhosis patients using results of biochemical analysis and method of fluorescent dyes. It was shown that the most effective sorbents were sorbents of "Prometheus" and between charcoal heamosorbents - "Carbocol"

EVALUATION OF THE FUNCTIONAL PROBABILITIES OF THE BLOOD PLASMA TRANSPORT SYSTEMS OF THE LIVER CIRRHOSIS PATIENTS BY THE FLUORESCENT PROBES METHOD AND ASSESSING OF HYDROPHOBIC SUBSTANCES ELIMINATION AFTER HEMOSORPTION AT THESE PATIENTS

The results of investigation of the main blood plasma transport proteins binding ability at liver cirrhosis patients by the fluorescent probes method are presented. It is shown that fluorescent probes method allows to get express information about functional state of the main blood plasma transport proteins at liver cirrhosis patients, promptly assess the disease severity, and according to this information change their treatment quickly