Integrated terahertz TEM horn antenna

A terahertz transverse electromagnetic horn antenna (THz-TEMHA) monolithically integrated on a gallium arsenide substrate has been studied by means of subpicosecond pulses generated and measured on a 50 Omega coplanar waveguide. The measured reflection coefficient is below -10 dB from 100 GHz to about 1 THz. A terahertz ranging experiment was carried out in a monostatic configuration     

Efficacy of fluconazole in the treatment of upper gastrointestinal candidiasis in neutropenic patients with cancer: factors influencing the outcome

Fluconazole has proved to be effective in treating oropharyngeal and esophageal candidiasis in immunocompromised patients. However, sufficient data are lacking regarding the efficacy of this agent in neutropenic hosts. The aim of the present study was to determine the clinical and mycological efficacy of fluconazole and to define the factor(s) affecting the outcome of fluconazole therapy in severely neutropenic patients (peripheral neutrophil count, < 500/microL) with cancer who have oropharyngeal and/or esophageal candidiasis. One hundred eleven patients with 129 episodes of candidal infections were treated with intravenous and consequently oral fluconazole (200 mg/d and 100 mg/d, respectively). Overall clinical cure and mycological eradication rates were 82% and 56%, respectively. Persistent neutropenia (P < .01), infection with a non-albicans strain of Candida (P = .012), and administration of antifungal therapy during the second or a later neutropenic episode (P < .002) were independently associated with a worse outcome. We conclude that fluconazole is effective in the treatment of upper gastrointestinal candidiasis in neutropenic patients with cancer. Effective treatment of the underlying malignancy, with the resultant recovery from neutropenia, and the determination of the species of infecting Candida isolates are required for the prediction of the outcome of antifungal therapy.     

Monolithic integrated circuits incorporating InP-based heterostructure barrier varactors

Fully integrated monolithic circuits incorporating InP-based heterostructure barrier varactor (HBV) frequency multipliers have been fabricated via epitaxial liftoff and transfer-substrate techniques onto a quartz substrate. We have obtained a maximum output power of 6 mW at 288 GHz: corresponding to an overall efficiency of 6%. In addition, we have observed a 45-GHz, 3-dB bandwidth centered around 300 GHz for a constant input power of 70 mW.     

Analysis of electrical and photoelectrical properties of ZnO/p-InP heterojunction

A ZnO/p-InP heterojunction has been fabricated by dc sputtering of ZnO on p-InP. It has been observed that the device has a good rectification. The electrical properties of the device such as ideality factor, barrier height, series resistance have been calculated using its current-voltage (I-V) measurements between 300 and 380 K with 20 K intervals. The short current density (J_sc) and open circuit voltage (V_oc) parameters have been determined between 40 and 100 mW/cm². The photovoltaic parameters of the device have been also determined under 100 mW/cm² and AM1.5 illumination condition.     

Fabrication of self-functionalized polymeric surfaces and their application in electrochemical acetaminophen detection

Conducting polymer coatings have offered functionalized surfaces having good electrical, mechanical, and physical properties. In this work, electrochemical preparation and characterization of polypyrrole/polypyrrole-3-carboxylic acid (PPy/PPa) copolymer onto single-use pencil graphite electrodes (PGEs) were described and detailed. Then, the application of these electrodes was demonstrated for the detection a commonly used analgesic, acetaminophen (AC) (paracetamol). Copolymer was deposited onto PGEs using cyclic voltammetry (CV) between +0.0 V and +1.0 V versus Ag/AgCl. Experimental conditions such as the effect of monomer ratios (3:1–6:1) and cyclic scans (1 cycle to 10 cycles) on electropolymerization were examined. Coated surfaces were characterized with CV and scanning electron microscopy. Electrochemical response of the electrode in AC at various pH values was evaluated. Then, AC detection was performed based on the oxidation signal of the drug at about +0.55 V versus Ag/AgCl using differential pulse voltammetry in buffer and body fluid (serum).     

Nanoleakage within adhesive-dentin interfaces made with simplified ethanol-wet bonding

Objective: The aim of the present study was to evaluate the effects of the simplified ethanol-wet bonding technique and conventional water-wet bonding technique on short term nanoleakage within hybrid layers made with two different etch-and-rinse adhesives (Single Bond 2 and Prime & Bond NT). Materials and methods: Flat dentin surfaces from bovine incisors were prepared and finished with wet 600-grit abrasive papers, then divided into groups to be bonded with one of the adhesives. After etching and rinsing, dentin surfaces were either moistened with water (water-wet bonding technique) or moistened with absolute ethanol for 1 min (ethanol-wet bonding technique). Then, adhesives were applied, and composite buildups were done. Bonded teeth samples were sectioned into resin–dentin samples by means of a low speed diamond saw under water cooling. Specimens were immersed into a 50% (w/v) solution of silver ammoniacal nitrate for 18 h and exposed to photodeveloping solution for 6 h. The amount of silver nitrate uptake within the adhesive layer, or hybrid layer, was measured with energy dispersive spectroscopy (EDS) in different regions (n = 30). Results: Simplified ethanol-wet bonding significantly reduced nanoleakage within resin–dentin interfaces made with Single Bond 2 and Prime & Bond NT, but improvement at the nanoleakage of Single Bond 2 was only significant. Conclusion: Simplified ethanol-wet bonding may improve quality of hybrid layers made with commercially available simplified etch-and-rinse adhesives. But benefits of ethanol-wet bonding may depend on product.     

Determination of textural deterioration in fish meat processed with electrospun nanofibers

Nano-applications are named as one of the novel methods, which provide many advantages like a larger contact area on the surface of fish fillets with less material. The goal of the study was to reveal the textural profile changes correlated with TPB growth of fish fillets coated with nanofibers having 2.47 ± 0.68 mV zeta potential value and 172 nm diameter. The difference of TPB count between control (CS) and the fish fillets treated with nanofibers (NG) reached 3.45 log CFU/g (p < .05) on the sixth day. The hardness value of CS was decreased (p < .05) (the decline: 68%) while the hardness of NG was found to be much more stable (the change: 42%). The highest change in springiness for CS and NG samples was determined as ~24 and ~15%, respectively, for 12 days. Cohesiveness values of CS were slightly increased, but those of the fish fillets coated with nanofibers were remarkably decreased. The coefficient of correlation analysis between TPB count and cohesiveness values was determined as “r = −.026 and r = .796” for CS and NG, respectively. Chewiness values of CS were significantly decreased (p < .05). However, chewiness values of the fish fillets coated with nanofibers were found as much more stable (p > .05). The results revealed that nanofiber coating limited the increase of TPB in fish fillets; it also better kept the textural profile of fish fillets as compared to CS stored at 4°C. The study could play a guiding role in further food nanotechnology applications in the industry and food science.