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In this study, an abundant and eco-friendly photocatalytic material, Fe2O3 particles were synthesized by sonochemical method. Morphological and microstructural investigations of synthesized undoped and Ni, Co-doped Fe2O3 particles were performed. The effect of particle morphology and microstructure on its photocatalytic performance was further investigated. Comparative studies for evaluating particle crystallite sizes were conducted by Williamson-Hall (W-H) method and modified Debye-Scherrer (MDS). Crystallite sizes and lattice strains of Fe2O3 induced by process parameters were calculated by W-H method based on uniform deformation model (UDM). The crystallite sizes of the synthesized powders were calculated in the range of 200 nm and 76 nm by Williamson-Hall analysis. In addition to structural investigation, dislocation density of the synthesized particles was calculated by Williamson-Smallman relation. Afterwards, photocatalytic performance of Fe2O3 particles was investigated in detail. The photodegradation of methylene blue solutions in the presence of light in 20 min with samples 3,4, and 5 in 20 min were 0.937, 0.896, and 0.855, respectively. Moreover, the photodegradation of methylene blue solution with sample 5 for 15, 30, and 45 min were 0.9, 0.828, and 0.757, respectively. A photocatalytic activity of 24.25% has been observed under optimum conditions for the time interval of 45 min.

In order to understand the current conduction mechanism in metal-semiconductor rectifier junctions, it is important to take electrical measurements depending on the sample temperature. Therefore, the current-voltage (I-V) measurements of the Au/Au-RGO/p-Si/Al structure were taken in the temperature range of 80–300 K by steps of 20 K. In the fabrication of the Au/Au-RGO/p-Si/Al structure, p-type Si was used as a base material. First, an ohmic contact was made by evaporating Al metal on the polished surface of the chemically cleaned p-Si and annealing in a nitrogen atmosphere at 580°C. Afterwards, mercaptoundecanoic acid-capped Au nanoparticles assembled on reduced graphene oxide (RGO), namely Au-RGO nanocomposite, was grown as an interfacial layer on the p-Si semiconductor substrate by the spin coating technique. The morphological and optical properties of the Au-RGO nanocomposite thin film were examined by atomic force microscopy (AFM) and Raman spectroscopy measurements. The I-V measurements of the Au/Au-RGO/p-Si/Al structure were taken depending on sample temperature and the basic electrical parameters such as ideality factor (n), barrier height (Φb) and dynamic resistance were calculated by means of thermionic emission method. It was observed that the ideality factor decreased and the barrier height increased with increasing sample temperature. The results were interpreted with the barrier inhomogeneity model and using Richardson plots.

Here, new carbon-based nanostructures were prepared via a one-step electrochemical method using hexagonal and pentagonal polychlorinated organic rings as the carbon source. The electrochemical growth of carbon nanostructures on substrates was accomplished via electrochemical reduction of organic halides in nonaqueous electrolyte solutions containing hexachlorobenzene (HCB), hexachlorocyclopentadiene (HCCP) and mixtures of HCB and HCCP with molar ratios of 2/2, 2/1.2 and 2/0.6. The effect of HCB/HCCP molar ratio, deposition time and temperature on the morphological and structural properties of the carbon coatings was investigated using spectroscopic and microscopic methods. The performance of the carbon nanostructures as supercapacitors was also studied using cyclic voltammetry, galvanostatic charge–discharge and electrochemical impedance spectroscopy in aqueous Na2SO4 solutions. The structural and chemical properties of the carbon nanostructures was found to depend strongly on the nature and relative molar ratios of the precursors used in the electrochemical reduction process. In the case of a 2/2 molar ratio of HCB to HCCP, mushroom-like carbon nanostructures are obtained, whereas, higher molar ratios of HCB to HCCP (2/1.2 and 2/0.6) result in carbon nanoflowers with graphitic features. Furthermore, the capacitance measurements show that these novel carbon structures are potential candidates for supercapacitor-based energy storage systems because they offer high specific capacitances (332–73 F g−1 at 0.5 A g−1), good cycling stabilities and a maximum energy density of 16 W h kg−1 at a power density of 250 W kg−1.

In this study, the influence of the film structure was investigated on the electrocatalytic oxygen reduction at GC electrodes covered with porphyrin and metalloporphyrin rings via the diazonium modification method. For that purpose, primarily, tetraphenylporphyrin (TPP) films on GC electrode surfaces were prepared by electroreduction of in situ generated diazonium salts of 5-(4-aminophenyl)-10,15,20-triphenylporphyrin (APP) and 5,10,15,20-tetrakis(4-aminophenyl)porphyrin (TAPP) molecules. Next, the formation of metalloporphyrin films on the modified surfaces was accomplished through the complexation reactions of surface porphyrin rings with metal ions in the salt solutions containing Mn(II), Fe(III) and Co(II) ions. The resulting porphyrin and metalloporphyrin layers were identified with XPS and ICP-MS. The electrochemical barrier properties of the films on GC surfaces were examined by cyclic voltammetry in K3Fe(CN)(6) aqueous solution. The electrocatalytic abilities of the resulting films were also investigated for the oxygen electrochemical reduction by employing cyclic voltammetry in PBS solutions saturated with oxygen. The results showed that the oxygen reduction potentials on modified GC electrodes were shifted to less negative potentials compared to that of bare GC electrode. Also, it was obtained that the oxygen reduction reaction was more effective on the GC electrodes modified with TPP rings by using TAPP molecules than those prepared by using APP molecules.

We report the fabrication, electrical characteristics and light sensitivity of n-TiO2/p-Si heterojunction devices in which the TiO2 layer was grown on p-Si substrates by cathodic electrodeposition. After the structural, morphological, and optical characterization of the deposited metal oxide film, 15 devices were fabricated. One was analyzed by current–voltage (I–V) and capacitance–voltage (C–V) analyses in a wide temperature range. Furthermore, another device was exposed to light and the I–V measurements were analyzed to investigate the light response of the n-TiO2/p-Si heterojunction. The device exhibited a photodiode property such that the reverse bias current value of the heterojunction significantly increased with exposure to the light. Temperature-dependent I–V and C–V measurements of the device showed that the device characteristics depend on both temperature and voltage. Thermionic emission and Norde method were used to evaluate temperature-related I–V measurements. According to the experimental results, it was observed that the barrier height increased [ranging from 0.24 eV (80 K) to 0.76 eV (300 K)] with increasing temperature and the ideality factor decreased [ranging from 4.94 (80 K) to 3.17 (300 K)]. This behaviour was attributed to the inhomogeneous barrier height of the n-TiO2/p-Si.

Mercaptoundecanoic acid capped-Ag nanoparticles (MUA-AgNPs) assembled on graphene oxide (GO), namely MUA-AgNPs-GO nanocomposite, was used for enhancing current–voltage (I–V) activity and stability of n-lnP based heterojunction devices. The structural, morphological and optical properties of the MUA-AgNPs-GO nanocomposite were examined by Raman spectroscopy, UV–Vis spectroscopy, transmission electron microscopy and scanning electron microscopy measurements. Besides, the Ag/MUA-AgNPs-GO/n-InP/Au-Ge heterojunction was fabricated, and working performance of the heterojunction was investigated in the temperature range of 80–320 K by steps of 20 K. The heterojunction created by the MUA-AgNPs-GO nanocomposite showed improved working performance such as better I–V characteristics, great stability and better rectifying ratio than that of our reference junction. The ideality factor and barrier height values of the junction formed with MUA-AgNPs-GO layer were found to be 1.07 eV and 0.630 eV, respectively. The experimental value of the Richardson constant was determined to be 3.82 A/cm 2 K 2 in the 80–160 K temperature range and to be 6.55 A/cm 2 K 2 in the 160–320 K temperature range. The results showed that the MUA-AgNPs-GO nanocomposite is a favorable candidate to provide modification of barrier height and to improve characteristic parameters for applications of the heterojunction devices.

In this paper, a novel electrochemical sensing platform has been developed based on the electrodes modified with heteroaromatic molecules decorated with gold nanoparticles (AuNPs). For this purpose, the GC electrodes were first covered with pyridine and phenanthroline rings by using diazonium reduction method. Then, the formation of AuNPs was achieved via the electrochemical reduction of AuCl4− ions preadsorbed to the modified GC surfaces. The AuNPs, for comparison, were also prepared on polyphenylene films (PPh) obtained by electrochemical reduction of in situ generated benzenediazonium salts. The existence of the nanoparticles was confirmed by using spectroscopic and electrochemical techniques such as scanning electron microscopy (SEM), X-ray photoelectron spectroscopy (XPS), X-ray diffraction (XRD), and cyclic voltammetry. The results have shown that the homogeneity of particle distribution is strongly dependent on the nature of the organic film. The electrocatalytic capabilities of the resulting composite films were also assessed both in the anodic and cathodic regions for hydrazine hydrate oxidation and nitrobenzene reduction, respectively. It was found that the AuNPs-modified electrodes showed a significant catalytic effect, since metal nanosites on the surfaces offer a good electrical conductivity and large effective surface area.

Graphene is a promising two-dimensional nanomaterial for many applications due to its exciting properties. In the past decade, a variety of techniques-each with its own set of advantages and disadvantages-have been developed to prepare graphene, and there are ongoing efforts to improve these techniques and to reveal new approaches. Here, we describe a simple and low-cost process for the bottom-up synthesis of graphene-like films. This new methodology involves a two-step procedure: (i) formation of polyaromatic ring structures by the repeated covalent coupling of aryl radicals generated from electrochemical reduction of polyhalogenated aromatic compounds in aprotic solvent, and (ii) production of carbon networks by heating of polyaromatic surface films. Accordingly, polymeric films were prepared on the electrodes by electrochemical reduction of polyhalogenated compounds such as hexafluorobenzene (HFB), hexachlorobenzene (HCB), and hexabromobenzene (HBB), and then polymer films were annealed at 400 °C for 30 min. The structure and surface characteristics of electrodeposited carbon films under self- and thermal-annealing conditions were studied by spectroscopic and morphological techniques. Also, the capacitance performance of the films was evaluated by means of cyclic voltammetry, galvanostatic charge-discharge, and electrochemical impedance spectroscopy. Results indicate that graphene-like carbon films can be achieved by use of the electrochemical approach under mild conditions without expensive equipment, and also that these carbon materials are very promising for low-cost energy-storage devices.

AuNPs and AuNPs/RGO composites were engineered as drug delivery nanoplatforms to efficiently deliver the anti-cancer drug to MCF-7 breast cancer cells. The anti-cancer drug, mitoxantrone (MTX), was tethered to the gold nanoparticles via a 3-mercaptopropionic acid (MPA) spacer and an acid-cleavable amid bond (SMTX-AuNPs). Then, the surface of the RGO nanosheets were decorated with SMTX-AuNPs (SMTX-AuNPs/RGO). For comparison purposes, MPA functionalized nanoparticles (MPA-AuNPs) and their nanocomposites (MPA-AuNPs/RGO) were also prepared using the same procedure. The formation of the nanomaterials was verified by spectroscopic and morphological techniques. The drug delivery activity of materials on MCF-7 cells was investigated in vitro using different methods. Our results demonstrate that SMTX-AuNPs have better activity on cancer cells than free MTX and SMTX-AuNPs/RGO. Further, contradicting previous studies, our findings suggest that the use of graphene-based materials for the covalent drug delivery systems need to be revisited.

In this report, we demonstrate a simple and eco-friendly process for the synthesis of gold nanoparticles (AuNPs) by using two different plant extracts -Ziziphus jujuba fruit and Gum arabic- as reducing and capping agents. GC–MS analysis of the extracts showed the existence of various biochemicals and phytochemicals such as amino acids, saccharides, phenols and terpenoids. The physical and morphological properties of AuNPs synthesized from extracts were characterized by UV–visible spectroscopy, dynamic light scattering (DLS) and field emission electron microscopy (FESEM). The results indicated that smaller particles (10–50 nm) were obtained with the Gum arabic, with homogeneity in size and spherical morphology. Infrared spectroscopy was employed to identify the possible functional groups responsible for capping and stabilization of the formed nanoparticles. The stabilities of the AuNPs were also investigated in phosphate buffer saline (PBS) media, and found that the AuNPs synthesized by Gum arabic compared to Ziziphus jujuba fruit extract displayed good stability for over two weeks and rising temperature.

Glycan-based alginate hydrogels have great potential in creating new vehicles with responsive behavior and tunable properties for biomedicine. However, precise control and tunability in properties present major barrier for clinical translation of these materials. Here, we report the synthesis of pH responsive anthracene modified glycan-based hydrogels for selective release of therapeutic molecules. Hydrogels were crosslinked through simultaneous photopolymerization of vinyl groups and photodimerization of anthracene. Incorporation of anthracene into these gels leads to reversible control on crosslinking and transition between gel/sol states through dimerization/dedimerization of anthracene groups. Chemotherapeutic drug doxorubicin-loaded hydrogels were then tested in a cancer mimetic microenvironment where 85% of the drug was released from anthracene-conjugated hydrogels at pH 2 for 6 days. Control on gelation with anthracene incorporation was observed through alterations in modulus, where storage modulus was increased two-fold with anthracene conjugation during photopolymerization and photodimerization. Furthermore, cell survival analysis revealed that anthracene conjugation could selectively compromise cancer cell viability without inducing significant toxicity on healthy fibroblasts. This study combines light-induced control of crosslink density due to anthracene and pH-triggered therapeutics delivery with alginate. The approach would be applicable for systems where multiple control is required with high precision., Scientific and Technological Research Council of Turkey (TÜBİTAK), International Support Program (COST Action - European Cooperation in Science and Technology); Koç University Seed Fund; Presidency of Turkey, Presidency of Strategy and Budget.

Some X-ray irradiation-induced electrical characteristics of the Au/anthraquinone/p-Si and the Au/pyridine/p-Si junction devices have been investigated. The experimental ideality factors increased for both devices with increasing irradiation dose from 25 Gy to 150 Gy. These values ranged from 1.10 to 1.52 for Au/anthraquinone/p-Si and from 1.46 to 1.77 for Au/pyridine/p-Si, respectively. Furthermore, the barrier height of Au/anthraquinone/p-Si increased with increasing irradiation dose from 0.75 to 0.91 eV, whereas it displayed about a constant value for Au/pyridine/p-Si. In addition, the series resistance of both devices increased with x-ray dose too. The increase in the series resistance with x-ray irradiation has been attributed to the decrease in the active dopant densities. It was seen that the ionization damage is effective on most of the junction characteristics. The leakage current of the Au/anthraquinone/p-Si device decreased with x-ray irradiation since the irradiation induced the formation of electron-hole pairs and hydroquinone structure, and thus some of them are trapped by the interface states. The degradation of the I-V curves of Au/pyridine/p-Si/Al device is attributed to the variation of the surface or interface states distribution for the devices. The reverse and forward bias currents relatively increased after x-ray irradiation because of the decrease in bulk lifetime. In addition, ATR-FTIR spectra of anthraquinone and pyridine films showed that pyridine is more stable than anthraquinone under x-ray irradiation.

WOS: 000382221100014 Mn-doped p-InSe semiconductor crystals were grown by Bridgman -Stockbarger technique. The crystals were analyzed by X-ray diffraction (XRD), scanning electron microscopy (SEM) and fabricated Sn/InSe: Mn Schottky diodes. The current-voltage (I-V) and capacitance-voltage (C-V) measurements of diodes were investigated to determine the response of devices to electron irradiation with 9 MeV energy and 1.2x10(10) e-cm(-2) dose. After irradiation, the ideality factor and barrier height of the Sn/InSe: Mn Schottky diode were determined as 1.66 and 0.85 eV, respectively. Before irradiation, they were determined as 1.37 and 0.90 eV, respectively. It has been concluded that the radiation with high energy may contribute to form defects at the interface of the Sn/InSe:Mn device.

The n-TiO2/polyphenylene (PPh)/p-Si heterojunction devices were fabricated in which PPh film and TiO2 top layer were grown on p-Si substrates by diazonium modification method and cathodic electrodeposition, respectively. The XPS, UV–vis diffuse reflectance and STM analyses of the films were performed. After the characterization of deposited films and the fabrications of n-TiO2/PPh/p-Si sandwich devices, the electrical measurements of nine devices were carried out from the current–voltage (I–V) characteristics, at room temperature. The I–V characteristics of n-TiO2/PPh/p-Si heterojunctions were compared with TiO2/p-Si heterojunctions, one of them was analysed in more detailed and it was observed that the n-TiO2/PPh/p-Si gave better performance than TiO2/p-Si heterojunctions such that lower ideality factor, higher rectification ratio and more stable reverse current characteristics. Then, the main device parameters of n-TiO2/PPh/p-Si were compared with many devices reported in literature based on TiO2/p-Si device and TiO2 preparation techniques. Furthermore, the rectification ratio of n-TiO2/PPh/p-Si heterojunction was 9.42 × 105, while it was 5.80 × 102 for TiO2/p-Si heterojunction. Later, the capacitance-voltage (C–V) and conductance-voltage (G-V) measurements of the n-TiO2/PPh/p-Si heterojunction was performed depending on applied frequency and bias and it was observed that the values of capacitance and conductance were found a strongly function of bias voltage.

Here, we report the synthesis of hollow porous gold nanoparticles-decorated reduced graphene oxide (HPAuNPs/RGO) nanocomposites and their electrochemical performances as active electrode material for supercapacitors. Accordingly, the HPAuNPs were first prepared using a simple solution phase template method according to the modified literature procedure, and the size control of hollow porous gold particles was achieved by varying the concentration of hydroquinone used as the reducing agent. Then, the surface of the RGO nanosheets was decorated with HPAuNPs through the self-assembly approach. The structural and morphological features of synthesized nanoparticles and nanocomposites were evaluated by spectroscopic and morphologic methods. Also, the electrochemical supercapacitive performances of the HPAuNPs/RGO/GC nanocomposite electrodes as both cathode and anode materials were analyzed in Na2SO4 solution using electrochemical methods. As a control sample, the RGO/GC electrode was also examined under identical experimental conditions. The results indicate that the composite materials display higher specific capacitances (107–325 F/g) compared with bare RGO (55 and 37 F/g) at a potential scan rate of 20 mV/s. Furthermore, it is obtained that the specific capacitances of the composite electrodes based on hollow porous gold nanoparticles are larger than those of previously reported supercapacitors with spherical gold nanoparticles/graphene as electrode materials. The improved electrochemical properties of the HPAuNPs/RGO/GC nanocomposite electrodes can be ascribed to the hollow and porous structure of the gold particles on RGO sheets.

An anthracene film has been deposited on an n -type silicon to fabricate an Au/anthracene/ n -Si junction device. The band gap of the anthracene film has been determined from the optical measurement as E g =1.65 eV. After the fabrication of the Au/anthracene/ n -Si junction device, temperature dependent capacitance–voltage characteristics in the range of 160–300 K were studied to obtain the junction parameters of the device. The diffusion potential, barrier height, Fermi energy level and donor concentration parameters have been determined from the linear 1/ C 2 –V curves with reverse bias at all temperatures. Both Fermi energy level and the barrier height increased with the increasing temperature. Temperature-dependence of the barrier height has been attributed to inhomogeneous barrier, traps and interface states. The ionized donor concentrations have varied with the temperature in an unsystematic manner due to the trapping/de-trapping of the charges at various temperatures.

Simkania negevensis, a recently discovered Chlamydia-like organism, has been associated with respiratory infections such as pneumonia, bronchiolitis and chronic obstructive pulmonary disease in children and adults. The aim of the present study was to evaluate S. negevensis in the etiology of pediatric community-acquired pneumonia, bronchiolitis and asthma exacerbation in our region. Overall, 102 patients and 46 healthy controls were included in the study. S. negevensis was investigated by real time PCR (Primer Design, UK) in nasopharyngeal swab samples. It failed to be detected in either the study or control group. In conclusion, our results suggest that S. negevensis is not an important respiratory pathogen in our region.

The attachment of organic molecules onto the silicon surfaces is of crucial interest for the development of nanoscale organic–inorganic hybrid materials. In this study, the electrografting of diazonium salts has been used for covalent attachment of the molecules to H-passivated silicon (100) surface. The modification of silicon electrodes with quinoline molecules was carried out through electrochemical reduction of in situ generated diazonium salts from 6-aminoquinoline, and thus an Au/quinoline/p-Si device was fabricated. The results measured from the as-deposited device displayed a higher barrier height at room temperature due to the formation of an interfacial dipole at a metal/organic interface during electrochemical deposition. It has been shown that the barrier height value was increased with the increasing temperature. In addition, there were seen two different behaviours of the temperature-dependent ideality factor and this was attributed to the response of quinoline to temperature below and above 160 K such it is likely to take place phase change at the interface. Such a temperature dependence of the barrier height was explained by the Gaussian distribution of the barrier heights due to the barrier height inhomogeneities at the quinoline film/p-type silicon interface. The mean barrier height and the standard deviation σ values were determined as 0.87 eV and 0.0989 V, respectively. Furthermore, the Norde model was also used for determining the temperature-dependent of barrier height and it was seen that there was a good agreement between that of the common ln(I)–V and Norde model.

Bu yazida 12 yasinda saglikli erkek bir olguda dikis ignesi ile yaralanma sonucu dizde gelisen septik artrit sunulmaktadir. Olgunun radyolojik incelemesinde femur medial kondilde metalik yabanci cisim gozlendi. Olguya klinik, radyolojik ve laboratuvar incelemeleri sonucu septik artrit tanisi konuldu. Hemen artroskopik debridman yapilarak yabanci cisim cikartildi. Cerrahi sonrasi ikinci gunde kultur sonucu Pseudomonas aeruginosa seklinde bildirilen olgunun antibiyotik tedavisi baslandi ve 6 hafta devam edildi. Postoperatif donem sorunsuz seyretti, hastanin eklem hareketleri normale dondu.

A pair of Mn-III(quinazolinone) complexes was prepared and evaluated in the catalytic epoxidation of the chiral allylic alcohols and unfunctionalised alkenes with iodosylbenzene. Epoxidation of chiral allylic alcohols with 1,3-allylic strain proceeded chemo- and diastereoselectively to give threo-epoxy alcohol (up to 99% d.r). Epoxidation of unfunctionalised alkenes by the proposed catalyst system proceeded nonselectively, as evidenced by the formation of isomerization and rearrangement products in the epoxidation of (Z)-stilbene. A three-step pathway involving a cationic intermediate is proposed for the formation of isomerization and rearrangement products. The fact that only products resulting from the cationic intermediate were detected in the oxidation of a mechanistic probe, (2-methoxy-3-vinylcyclopropyl)benzene, with Mn-III(quinazolinone) and PhIO substantiated the cationic oxygen transfer mechanism. (C) 2017 Elsevier Ltd. All rights reserved.

Microwave-assisted extraction(MAE) is commonly used in recent years as an innovative approach to enhancingthe quality of extracts while decreasing the extraction time and the solventconsumption in comparison to conventional techniques. In this study, theinfluence of microwave power, solid concentration and extraction time on totalphenolic content (TPC), colour values and dielectric properties of Caucasianwhortleberry were investigated. The process variables were optimized usingresponse surface methodology. The highest TPC from Caucasian whortleberry wasobtained at an extraction time of 3.5 min, a solid concentration of 15% and amicrowave power of 360 W. The results showed that L* and a* values of theextracts were highly correlated with TPC by a second-order polynomial.Moreover, no significant difference was found in dielectric properties betweenthe groups., Mikrodalga-destekli ektraksiyon (MAE), konvansiyoneltekniklerle ile karşılaştırıldığında ekstraksiyon süresi ile solvent tüketiminidüşürürken, ekstrakt kalitesini arttırması nedeniyle yenilikçi bir yöntemolarak son yıllarda yaygın bir şekilde kullanılmaktadır. Bu çalışmada,mikrodalga gücü, katı konsantrasyonu ve ekstraksiyon süresinin, likapameyvesinin toplam fenolik içeriği (TPC), renk değerleri ve dielektriközellikleri üzerine etkisi incelenmiştir. Proses değişkenleri yanıt yüzeyyöntemi kullanılarak optimize edilmiştir. Likapadan en yüksek TPC, 360 Wmikrodalga gücü, %15 katı konsantrasyonu ve 3.5 dakika ekstraksiyon süresikoşullarında elde edilmiştir. Sonuçlara bakıldığında, ekstrakların L* vea* değerleri, TPC ile ikinci derecedenpolinom ile yüksek korelasyon göstermiştir. Ayrıca, grupların dielektriközellikleri arasında anlamlı fark bulunamamıştır.

Background Plasma gelsolin is a circulating actin-binding protein that has a protective role against tissue injuries. Our aim was to compare the baseline levels of gelsolin in premature infants with neonatal outcomes. Methods A total of 32 preterm neonates born at 23–32 weeks of gestation were enrolled in the study. Results Plasma gelsolin levels at 72 h were significantly lower in patients with respiratory distress syndrome, in patients who were administered surfactant therapy and in patients who developed sepsis (P < 0.05). Plasma gelsolin levels at 28 days were significantly lower in patients who developed bronchopulmonary dysplasia and retinopathy of prematurity (P < 0.05). Conclusions Low plasma gelsolin levels in the first postnatal month may be associated with poor outcomes in premature infants.

The aim of this paper is to compare the effect of nebulized magnesium sulfate to nebulized salbutamol and salbutamol/magnesium sulfate on successful discharge from the emergency department. A total of 56 infants were included in this double-blinded, prospective study. Infants were grouped according to the nebulized treatment they received: group 1-salbutamol/normal saline, group 2-magnesium sulfate and normal saline, and group 3-salbutamol plus magnesium sulfate. Heart beat, bronchiolitis, clinical severity scores (CSS), and oxygen saturation of the patients were determined before and after nebulization (0, 1, 4 h). The patients were monitored for adverse reactions. Post-treatment mean CSS results were significantly lower than pre-treatment scores in all groups at 4 h with no significant difference within groups. CSS scores were lower in the salbutamol/magnesium sulfate group when compared with the magnesium sulfate and salbutamol groups (3.4 (2.4-4.3), 4.7 (3.8-5.7), 4.0 (3.2-4.3)). CSS were significantly lower than those from the magnesium sulfate group. Conclusion: Nebulized magnesium sulfate plus salbutamol may have additive effects for improving the short-term CSS.

The Au/Anthracene/ n -Si/Al MIS device was fabricated on the basis of anthracene film covalently bonded to a Si substrate. The MIS device showed Schottky behavior with barrier heights of 0.85 eV and ideality factors of 1.88 at 300 K. The barrier height of the Au/ n -Si has increased after deposition of the anthracene layer onto Si. Temperature dependent current–voltage ( I – V ) measurements were performed on the Au/Anthracene/ n -Si/Al MIS diodes in the range 140–300 K. From the temperature dependence of forward bias I – V , the barrier height was observed to increase with temperature. However, the ideality factor decreased with increasing temperature. The values of activation energy ( E a ) and Richardson constant ( A *) were determined as 0.24 eV and 7.57 × 10 −6 A cm −2 K −2 from the slope and the intercept at ordinate of the linear region of Richardson plot, respectively. The increase of the series resistance R s with the fall of temperature was attributed to lack of free carrier concentration at low temperatures.

Aviyente, Viktorya/0000-0001-9430-4096; Kazak, Canan/0000-0003-2475-8775; Tuzun, Nurcan/0000-0001-5225-3876 WOS: 000329958400015 Twelve indene-fused dialkynyl substituted anthracene derivatives (indenoanthracenes) were synthesized and their optical, electrochemical and thermal properties were described. These small molecules possess high quantum yields, thermal and photoxidative stabilities, and solubility in common organic solvents. Indenoanthracenes (57-92%) were prepared in two steps from four different indenoanthraquinones obtained via a highly selective and practical benzocyclobutendione based methodology. The photophysical properties of indenoanthracenes were investigated by UV-vis and fluorescence spectroscopies. From spectroscopic data of indenoanthracenes, quantum yields (Phi(f), 0.28-0.71) and optical HOMO-LUMO energy gaps were determined. Electrochemistry of indenoanthracenes was studied and electrochemical HOMO-LUMO energy gaps were also determined from the onset oxidation and reduction potentials. Density functional theory calculations were performed to obtain the geometry optimized structures and HOMO-LUMO energy levels. Fluorenylethynyl substituted indenoanthracene was employed as an emitting layer in a solution processed OLED device and the maximum current efficiency and luminance were found to be 1.02 cd/A and 1284 cd/m(2), respectively. (C) 2013 Elsevier Ltd. All rights reserved. Scientific and Technical Research Council of TurkeyTurkiye Bilimsel ve Teknolojik Arastirma Kurumu (TUBITAK) [TBAG-110T566]; Research Board of Istanbul Technical UniversityIstanbul Technical University [BAP-34956, BAP-34335]; Feyzi Akkaya Science Foundation (FABED) The authors thank the Scientific and Technical Research Council of Turkey (TBAG-110T566), the Research Board of Istanbul Technical University (BAP-34956 and BAP-34335) and Feyzi Akkaya Science Foundation (FABED) for financial support of this research.

We report on the synthesis of graphene through the simple electrochemical reduction of graphite oxide (GO) on gold electrodes from an aqueous dispersion of GO at cathodic potentials determined by cyclic voltammetry measurements. The removal of the oxygen-containing functional groups and chemical structural changes during the electrochemical reduction were monitored by Fourier transform infrared spectroscopy, X-ray diffraction, and Raman spectroscopy. The atomic structure and size of reduced GO nanostructures on Au(111) were characterized using scanning tunneling microscopy. The results showed that the electrochemical technique could be used for the synthesis of reduced GO and graphene-based nanomaterials. These findings are promising for the development of an electrochemical approach for the direct fabrication of reduced GO electrodes without additional modifications in electrochemical applications.

In this work, an Au/Anthracene/n-Si/Al Schottky barrier diode was fabricated and it was found that the diode showed good rectification properties. The characteristic parameters of the device such as barrier height, ideality factor, interface states density and series resistance were determined from the current–voltage measurements. It was seen that the Anthracene organic layer increased the effective barrier height of the Au/n-Si/Al diode since this layer creates the physical barrier between the Au and n-Si. Furthermore, the current–voltage characteristics under forward bias were found to be ohmic due to conduction at lower voltage regions. At higher voltage regions there is space charge limited conduction (SCLC) mechanism. Furthermore, the capacitance–voltage curves of the Au/Anthracene/n-Si/Al Schottky barrier diode were analyzed in the various frequencies as a function of the bias.

Crimean-Congo hemorrhagic fever infection (CCHF) is a viral zoonosis. The pathogenesis of this disease has not been established so far, however cytokines account for its progression and outcome. The aim of the present study is to investigate the association between chemokine receptor 5 (CCR5) gene Δ32 mutation and pathogenity, severity, and mortality of CCHF. This case-control study included 133 CCHF patients diagnosed by detection of CCHV RNA positivity and 97 healthy control subjects. CCR5 gene Δ32 mutation analyzed by polymerase chain reaction (PCR) method. The results were compared by using SPSS 16.0 and WINPEPI software's. The genotype distribution and allele frequency of the CCR5Δ32 were statistically different between the patients and the control group (p = 0.017; OR: 4.98 95% CI = 1.65-14.99 and p = 0.019; OR:4.76 95%CI = 1.30-17.50, respectively). CCR5/CCR5 (W/W) genotype and W allele of CCR5 gene were more common in patient group than in controls. There was no significant difference in severe and mild cases with regard to genotype distribution and allele distribution of CCR5Δ32 mutation (p > 0.05). These results suggest that the CCR5 gene and its product might play a role in the pathogenesis of CCHF disease. Future studies will help us to uncover the exact role of CCR5 in the pathogenesis and prognosis of CCHF and to treat the disease. This article is protected by copyright. All rights reserved

Neutral, hydrophilic, polymer-based architectures are widely investigated for a wide range of biomedical applications from drug-conjugates to delivery systems and scaffolds for regenerative therapies. In most cases, it is crucial that biomaterials provide a blank, inert background in order to hinder unspecific cell-material interactions so that protein mediated biological events leading to foreign body reactions are prevented. Hydrophilic polyglycerol-based polymer network films are a recently developed class of amorphous macroscopic materials, which offer great versatility in design and control of resultant properties. In this study, protein adsorption on polyglycerol-based polymer network films is investigated by using Micro BCA protein assay for three types of proteins having critical roles in the human body, and various copolymer networks with differing sidechains and crosslink densities.

In this study, a simple and reliable cyclic voltammetry and linear sweep voltammetry method were developed and validated for determination of carvedilol in pharmaceutical preparations. The proposed method was based on electrochemical oxidation of carvedilol at platinum electrode in acetonitrile solution containing 0.1 m TBAClO4. The well defined three oxidation peaks were observed at 1.02, 1.17 and 1.42 V, respectively. Calibration curve that obtained by using current values measured for second peak was linear over the concentration range of 5–40 μg/ml. Intra- and inter-day precision values for carvedilol were

Polyacrylamide nanoparticles containing zinc nitrate were prepared via inverse miniemulsion polymerization using ultrasound emulsification. The effects of sonication time, mode of sonication, nature and type of emulsifier, amount of zinc salt, solvent in the dispersed phase, nature of dispersed and continuous phases, and type of initiator on the nucleation mechanism, conversion, molecular mass of polymer, and size distribution of the latex particles were investigated. The results showed that an increase in sonication time up to 4 min and using an amphiphilic polymeric surfactant with a relatively short hydrophilic part improved both the monodispersity and the stability of the zinc-containing latexes. An increase in viscosity of the continuous phase (changed by means of different nonpolar solvents) and decrease in viscosity of the dispersed phase (varied by the amount of water) had also a positive effect on the monodispersity. At the same time, the average diameter of the particles in the range of 225 nm c...

WOS: 000390510900151 Dye-sensitized solar cells (DSSCs) provide a low cost alternative to the conventional solar cells due to their easy and inexpensive device fabrication steps. Generally, F:SnO2 (FM) conductive glass with a thin layer coating of platinum (Pt) is used as a counter electrode (CE) in DSSCs. Since Pt is rare and therefore expensive metal, we were looking for a way to produce a new counter electrode based on graphene/iron pyrite (FeS2) thin films as an alternative to the Pt:FTO. In combination with a TiO2 mesoporous photo anode and an I-3(-)/I- redox electrolyte, graphene/FeS2 CE based DSSC shows eta =7.43% energy conversion efficiency under 1 sun illumination (100 mW/cm(2), AM 1.5G) which is approximately 16.1% higher than conventional Pt CE (eta=6.40%). External Quantum Efficiency (EQE) is found to be shifted upward when graphene/FeS2 is used as CE in the place of Pt CE. The excellent performance of the graphene/FeS2 CE makes it a very promising alternative to costly Pt in DSSCs. (C) 2016 Published by Elsevier B.V. Turkiye Bilimsel ve Teknolojik Arastirma Kurumu (Scientific and Technological Research Council of Turkey) (TUBITAK) [114F292]; TUBITAKTurkiye Bilimsel ve Teknolojik Arastirma Kurumu (TUBITAK) This project was supported by Turkiye Bilimsel ve Teknolojik Arastirma Kurumu (Scientific and Technological Research Council of Turkey) (TUBITAK) Project number: 114F292. The authors would like to thank TUBITAK for giving a support.

The electrochemical oligomerization of 2-amino-3-cyano-4-methylthiophene (ACMT) has been studied by cyclic voltammetry, potential controlled electrolysis and digital simulation. The product analysis after preparative electrolysis was carried out by UV-vis-NIR, 1 H and 13 C NMR and FT-IR spectroscopic techniques. The kinetic data were estimated using the results of fitting the digitally simulated voltammograms to the experimentally obtained cyclic voltammograms. The oligomerization proceeds according to an ECE mechanism resulting in the formation of an oligomeric mixture containing dimer and tetramer. UV-vis-NIR and fluorescence measurements indicated that the isolated dimer and tetramer showed higher conjugation than the monomer unit and the conjugation increased with an increase in the number of monomer units.

In this study, we synthesized the amine compound 2-(2-aminoethyliminomethyl)phenol (H(3)A) as the starting material, and then we prepared the polydentate Schiff base ligands from the reactions of the amine compound (H(3)A) with phtaldialdehyde (H(2)L), 4-methyl-2,6-di-formlyphenol (H(3)L(1)) and 4-t-butyl-2,6-di-formylphenol (H(3)L(2)) in the ethanol solution. Moreover, the complexes Cd(II), Cu(II), Co(II), Ni(II), Zn(II) and Sn(II) of the ligands H(2)L, H(3)L(1) and H(3)L(2) have been prepared. All compounds have been characterized by the analytical and spectroscopic methods. In addition, the magnetic susceptibility and molar conductance measurements have been made. The catalytic properties of the mono- and binuclear Co(II) and Cu(II) complexes have been studied on the 3,5-di-tert-butylcatechol (3,5-DTBC) and ascorbic acid (aa) as a substrate. The oxidative C-C coupling properties of the Co(II) and Cu(II) complexes have been investigated on the sterically hindered 2,6-di-tert-butylphenol (dtbp). The antimicrobial activity properties of the ligands and their mono- and binuclear complexes have been studied against the bacteria and fungi. The results have been compared to the antibacterial and fungi drugs. The TGA curves show that the decomposition takes place in three steps for all complexes. Electrochemical properties of the complexes Cu(II) and Ni(II) have been investigated for the first time in acetonitrile by cyclic voltammetry.

Novel aminothiophene-based dimer, oligomers, and polymer were synthesized by the electrochemical oxidation of 2-amino-3-cyano-4-β-naphthylthiophene (β-ACNT). These products obtained after a preparative electrolysis were characterized by FTIR, 1H and 13C NMR, FAB-MS, and UV−vis−NIR spectroscopy. Additionally, scanning tunneling microscopy (STM) was used to investigate the thin film morphology of polyaminothiophene. Results showed that 2-amino-3-cyano-4-β-naphthylthiophene could be electropolymerized, leading to one stable dimer, which has a long conjugation length with a fluorescent property at 538 nm, and a mixture of oligoaminothiophenes. UV−vis−NIR spectroelectrochemistry of a thin film of polyaminothiophene on ITO shows low-energy absorptions at 542, 830, and 1050 nm, which are blue-shifted compared to the absorptions obtained in solution. STM results indicate that the surface of single crystalline Au(111) is completely covered with a highly oriented thin film of polymer.

The anodic oxidation of 2-amino-3-cyano-4-naphtylthiophene (ACNT) was studied for the first time by cyclic voltammetry, digital simulation and in situ spectroelectrochemical techniques. The kinetic data were estimated using the results of fitting the digitally simulated voltammograms to the experimental data. All electrochemical evidence indicates that the oligomerization mechanism is ECE and the main reaction path of the oligomer formation involves the coupling of the dimeric cation radical of RC–PM with neutral ACNT molecules or other radical species. The in situ UV–Vis–NIR spectra of the dimers and oligomeric mixture indicated that new species with a low energy absorption (365, 537, 828, and 1055 nm) formed during the electrooxidaton of ACNT.

There are evidences that besides geographic tendency, interactions between genetic and environmental factors play an essential role in the pathogenesis of Behcet’s disease (BD). In this study, we have evaluated the associations between rs4810485 and rs1883832 single nucleotide polymorphism (SNP)s of CD40 gene with the susceptibility and clinical findings of BD. Two hundred and eighty-five patients with BD and 225 age-matched healthy controls were enrolled in this study. The clinical findings of patients were noted. The distributions of genotypes, alleles, combined genotypes and haplotypes of these two SNPs in BD patients were compared with those in healthy controls. In further evaluation, we evaluated the patients with and without any of clinical findings with regarding to distribution of genotypes and alleles of these two SNPs. There was no significant difference concerning frequencies of genotypes, alleles, combined genotypes and haplotypes of rs4810485 and rs1883832 between patients and controls (p > 0.05 for all). Frequency of GT genotype of CD40 rs4810485 polymorphism was found to be significantly higher in patients with skin lesions (p

Plasma gelsolin is a circulating actin-binding protein that has a protective role against tissue injuries. Our aim was to compare the baseline levels of gelsolin in premature infants with neonatal outcomes.A total of 32 preterm neonates born at 23-32 weeks of gestation were enrolled in the study.Plasma gelsolin levels at 72 h were significantly lower in patients with respiratory distress syndrome, in patients who were administered surfactant therapy and in patients who developed sepsis (P0.05). Plasma gelsolin levels at 28 days were significantly lower in patients who developed bronchopulmonary dysplasia and retinopathy of prematurity (P0.05).Low plasma gelsolin levels in the first postnatal month may be associated with poor outcomes in premature infants.

The electrooxidation of 2-amino-3-cyano-4-phenylthiophene on platinum electrodes was investigated for the first time in acetonitrile by cyclic voltammetry, controlled potential electrolysis, and spectrometric methods. The voltammetric responses were similar to those of common aromatic amino compounds. Two types of dimers were observed as intermediates in the early stages of oxidation. Ethlyamine and phenol were added to an electrolytic solution in order to determine the electrochemical behavior of 2-amino-3-cyano-4-phenylthiophene under basic and acidic conditions. We propose an E(CE)n mechanism to account for this electrochemistry. 2-Amino-3-cyano-4-phenylthiophene is first oxidized to a cation radical, followed by chemical coupling to form dimers, which are electroactive. Controlled potential electrolysis gave a new class of π-conjugated oligoaminothiophenes exhibiting an absorbance at 432 nm and photoluminescence at 538 nm.

Garcia-Granda, Santiago/0000-0002-2373-0247; Hokelek, Tuncer/0000-0002-8602-4382 WOS: 000185047100091 The title compound, C6H6N2S, consists of a thiophene ring carrying three substitutent groups. Two N-H...N intermolecular hydrogen bonds link neighboring molecules into a three-dimensional network.

In this study, we report the electrochemical polymerization of 9-benzylfluorene (9-BF) in acetonitrile solution. The characterization of the resulting poly(9-BF) film obtained on the working electrode has been performed by using attenuated total reflectance infrared spectroscopy. Besides electrochemical properties, the optical and photoluminescent properties of film were also investigated in detail by means of UV–Vis spectroscopy and fluorescence spectroscopy. Fluorescent spectral studies indicate that polymer film in solid state emits blue-green light at around 470/520 nm under irradiation of UV light. In addition, scanning tunneling microscopy was used to investigate the morphology of poly(9-BF) film. The morphological results also reveal that the surface of single crystalline gold electrode is completely covered with the polymer film.

In this paper, two new thiols, [4-(9H-fluoren-9-ylmethyl)-phenyl]-methanethiol (6a) and [4-(2-nitro-9H-fluoren-9-ylmethyl)-phenyl]-methanethiol (6b), were synthesized, and self-assembled monolayers (SAMs) of these thiols were formed on gold electrodes. The structure and surface properties of molecular films were investigated by contact angle measurements and attenuated total reflectance infrared spectroscopy (ATR-FTIR). The blocking behavior of Au-6a and Au-6b SAMs was examined with cyclic voltammetry in the presence of redox probes such as K3Fe(CN)(6), Ru(NH3)(6)Cl-3 and ferrocene. Electrochemical measurements revealed that the voltammetric behavior of the redox probes was dependent on the nature of the probe molecules, the electrolytic solution composition and the monolayer structure. The optical properties of the SAMs were studied by steady-state and time-resolved fluorescence spectroscopy. It was obtained that the fluorescence emission bands of Au-6a and Au-6b monolayers were red-shifted and broadened compared to those of free thiols in solution as well as significant reduction at their emission intensities. The fluorescence decay profiles of 6a and 6b monolayers were described by a monoexponential function. In order to determine the possible deactivation mechanism between the metal support and photoexcited molecules, spectroelectrochemical steady-state fluorescence and lifetime measurements on the Au-fluorophore electrodes were also performed as a function of the applied potential. These results indicate that the fluorescence quenching occurs via an energy transfer mechanism from the excited molecules to the gold substrate. (C) 2011 Elsevier B.V. All rights reserved.

Synthetic polymeric materials are established as being central to many modern approaches to medical treatments such as biomaterial induced tissue regeneration or drug eluting implants. Cytocompatible, antifouling materials, based on hydrophilic polymers such as poly(ethylene glycol), have been widely studied as a ‘blank canvas’ substrate; it is possible to apply various bioactive ligands to elicit specific tissue and cell responses. In recent years, branched polyglycerols have gained attention as a viable alternative to PEG as a protein-resistance providing chemical moiety. To this end we have embarked on the preparation of bulk polyglycerol-based films, which are readily synthesized from abundant starting materials, with the aim of evaluating their as yet undiscovered potential as macroscopic biomaterials. Herein we report syntheses, as well as mechanical, and rheological properties of a series of polyglycerol-based polymer networks. Polymeric films produced are highly crosslinked, have high thermal stability, and are flexible with thermal glass transition temperatures below body temperature.

Poly(ε-caprolactones) (PCLs) belong to the first generation of synthetic aliphatic polyesters. Their biodegradability motivated their extensive exploration as resorbable materials, particularly in controlled drug release applications. While PCL fell out of fashion due to the increasing popularity of shorter chain polyglycolides and derivatives, there has been a noticeable renewed interest in ε-caprolactone derived components for copolymer systems with advanced functions in the last decade or so. PCL has particular properties that are attractive for the design of tunable biomaterials such as slow crystallization kinetics and low melting temperatures in the physiological range. Slow degradation rates, with relatively minimal acid generation, can be valuable for prolonged drug release or longer-term stability of implants. Herein we cover recent developments of PCL chemistry, focussing on innovative uses of ε-caprolactone-based segments in sophisticated polymer architectures such as multiblock copolymer networks, and micellar systems. Such polymer constructs are of high interest for biomedical applications.

By green synthesis method utilization and using two plants, Mentha and Pelargonium plant extracts, gold nanoparticles were synthesized. For medical applications gold nanoparticles performance was observed in PBS media which is as like as human blood. Important features of green synthesized gold nanoparticles were measured using, GC-MS, UV-vis, FESEM, DLS and FT-IR. Main goal of this research was investigating reducing and stabilizing effects of mentioned plants, which was confirmed by GC-MS results. DLS and FESEM results proved nanometric size of green synthesized gold nanoparticles. For describing the performance, might be said that both extracts lead to synthesis of gold nanoparticles which their sizes are identical. Also, the synthesized gold nanoparticles from both plant extracts didn’t agglomerated. Result of investigating performance of synthesized gold nanoparticles in PBS media indicates that both extracts will synthesize nanoparticles which will be stable by passing time or increased temperature.