Fabrication and characterizations of PCDTBT: PC71BM bulk heterojunction solar cell using air brush coating method

Organic solar cells have been significantly attracted due to the need to develop an inexpensive clean and sustainable renewable energy source. We report on the fabrication of poly [N-9″-hepta-decanyl-2,7-carbazole-alt-5,5-(4′,7′-di-2-thienyl-2′,1′,3′-benzothiadiazole)]/[6, 6]-phenyl-C₇₁-butyric acid methyl ester blend active layer using airbrush spray-coating method in mixed solvents. Optical absorption of the active layers was analyzed using UV–visible spectral studies in the wavelength range from 300 to 800 nm. The surface morphology of the active layers deposited with different parameters (spraying time and substrate-nozzle distance) was examined using atomic force microscopy. The current density–voltage (J–V) characteristics of photovoltaic cells were measured under the illumination of simulated solar light with 100 mW cm^?2 (AM 1.5G) by an Oriel 1000 W solar simulator. The power conversion efficiency of the solar cell is more than 5 %.     

Analyzing the performance of fuzzy cognitive maps with non-linear hebbian learning algorithm in predicting autistic disorder

The soft computing technique of fuzzy cognitive maps (FCM) for modeling and predicting autistic spectrum disorder has been proposed. The FCM models the behavior of a complex system and is used to develop new knowledge based system applications. FCM combines the robust properties of fuzzy logic and neural networks. To overwhelm the limitations and to improve the efficiency of FCM, a good learning method of unsupervised training could be applied. A decision system based on human knowledge and experience with a FCM trained using unsupervised non-linear hebbian learning algorithm is proposed here. Through this work the hebbian algorithm on non-linear units is used for training FCMs for the autistic disorder prediction problem. The investigated approach serves as a guide in determining the prognosis and in planning the appropriate therapies to special children.     

Facial expression recognition for monitoring neurological disorders based on convolutional neural network

Multimedia Tools and Applications - Facial expressions are a significant part of non-verbal communication. Recognizing facial expressions of people with neurological disorders is essential because...     

Effect of different solvents on volatile and non-volatile constituents of red bell pepper (<Emphasis Type="Italic">Capsicum annuum</Emphasis> L.) and their in vitro antioxidant activity

The fresh fruit of Capsicum annuum L. (red bell pepper) was successively extracted using n-hexane, chloroform, ethyl acetate, ethanol and their percentage yield was calculated. The effectiveness of each extract on chemical composition and antioxidant activity was studied. The qualitative phytochemical evaluation of each extract of bell pepper was done by HPTLC and Gas chromatography–mass spectroscopy (GC-MS) analysis. The total content of phenols, flavonoids and carotenoids were estimated by standard chemical methods. Further, the antioxidant potential of each extract was measured via DPPH and reducing power assays. Gas chromatography–mass spectroscopy analysis showed that the majority of compounds were related to phenols and flavonoids. Further analysis of the extract by HPTLC verified the presence of different types of phenolic compounds in addition to flavonoids and carotenoids. Among the different solvent extracts analyzed, total phenolic content was higher in ethanol extract (7.136?±?0.03%, w/w) whereas ethyl acetate extract showed the presence of higher flavonoid content (4.0521?±?0.03%, w/w). The ethanol and ethyl acetate extracts of the fruit of C. annuum exhibited the highest radical scavenging activity with inhibition percentage of 53.66 and 49.55% at a concentration of 254 µg/ml. Based on the biochemical analysis and phytochemical screening, we conclude that C. annuum possess potent antioxidant potential and this ability of the extract is attributed to the presence of rich polyphenolic compounds.     

Dietary ascorbic acid and alpha-tocopherol mitigates oxidative stress induced by copper in the thornfish Terapon jarbua

The protective effects of vitamins C and E against oxidative stress were evaluated in various tissues of thornfish Terapon jarbua exposed to copper. Preliminary bioassay tests performed with copper and T. jarbua revealed that 4.0, 2.5 and 1.0 mg L(-1) of copper were lethal (LC(100)), medial lethal (LC(50)) and sublethal (LC(0)) respectively. Oxidative stress parameters viz. lipid peroxidation, superoxide dismutase, catalase, glutathione peroxidase, and glutathione were evaluated in control and experimental fishes. Lipid peroxidation activity increased in tissues of copper exposed fishes, while the antioxidant system exhibited a reduction in their activity. On the contrary copper stressed fishes fed with vitamins C and E enriched pellet feed showed significant reduction in lipid peroxidation activity and the antioxidant levels increased reaching near normal levels comparable to control values. Bioaccumulation of copper was studied in addition to oxidative stress. Substantial copper residue was detected in the tissues of T. jarbua exposed to copper and the level of copper in tissues reduced when the fishes were treated with vitamins ensuring copper depuration and thereby protecting them against stress. We concluded that vitamin supplementation offered significant reduction of the oxidative stress mediated by copper and we discuss the possible application of vitamins in costal aquaculture process.     

Performance of viruses and bacteriophages for fecal source determination in a multi-laboratory,comparative study

An inter-laboratory study of the accuracy of microbial source tracking (MST) methods was conducted using challenge fecal and sewage samples that were spiked into artificial freshwater and provided as unknowns (blind test samples) to the laboratories. The results of the Source Identification Protocol Project (SIPP) are presented in a series of papers that cover 41 MST methods. This contribution details the results of the virus and bacteriophage methods targeting human fecal or sewage contamination. Human viruses used as source identifiers included adenoviruses (HAdV), enteroviruses (EV), norovirus Groups I and II (NoVI and NoVII), and polyomaviruses (HPyVs). Bacteriophages were also employed, including somatic coliphages and F-specific RNA bacteriophages (FRNAPH) as general indicators of fecal contamination. Bacteriophage methods targeting human fecal sources included genotyping of FRNAPH isolates and plaque formation on bacterial hosts Enterococcus faecium MB-55, Bacteroides HB-73 and Bacteroides GB-124. The use of small sample volumes (≤50 ml) resulted in relatively insensitive theoretical limits of detection (10–50 gene copies or plaques × 50 ml⁻¹) which, coupled with low virus concentrations in samples, resulted in high false-negative rates, low sensitivity, and low negative predictive values. On the other hand, the specificity of the human virus methods was generally close to 100% and positive predictive values were ∼40–70% with the exception of NoVs, which were not detected. The bacteriophage methods were generally much less specific toward human sewage than virus methods, although FRNAPH II genotyping was relatively successful, with 18% sensitivity and 85% specificity. While the specificity of the human virus methods engenders great confidence in a positive result, better concentration methods and larger sample volumes must be utilized for greater accuracy of negative results, i.e. the prediction that a human contamination source is absent.     

Control of melt pool temperature and deposition height during direct metal deposition process

This paper presents a hybrid control system that is able to improve dimensional accuracy of geometrically complex parts manufactured by direct metal deposition process. The melt pool height is monitored by three high-speed charged couple device cameras in a triangulation setup. The melt pool temperature is monitored by a dual-color pyrometer. A two-input single-output hybrid control system including a master height controller and a slave temperature controller is used to control both height growth and melt pool temperature at each deposition layer. The height controller is a rule-based controller and the temperature controller uses a generalized predictive control algorithm with input constraints. When the melt pool height is above a prescribed layer thickness, the master height controller blocks control actions from the temperature controller and decreases laser power to avoid over-building. When the melt pool height is below the prescribed layer thickness, the temperature controller bypasses the height controller and dynamically adjusts laser power to control the melt pool temperature. This hybrid controller is able to achieve stable layer growth by avoiding both over-building and under-building through heat input control. A complex 3-D turbine blade with improved geometrical accuracy is demonstrated using the hybrid control system.     

Isolation and characterization of Bacteroides host strain HB-73 used to detect sewage specific phages in Hawaii

Previous studies have shown that Escherichia coli and enterococci are unreliable indicators of fecal contamination in Hawaii because of their ability to multiply in environmental soils. In this study, the method of detecting Bacteroides phages as specific markers of sewage contamination in Hawaii’s recreational waters was evaluated because these sewage specific phages cannot multiply under environmental conditions. Bacteroides hosts (GB-124, GA-17), were recovered from sewage samples in Europe and were reported to be effective in detecting phages from sewage samples obtained in certain geographical areas. However, GB-124 and GA-17 hosts were ineffective in detecting phages from sewage samples obtained in Hawaii. Bacteroides host HB-73 was isolated from a sewage sample in Hawaii, confirmed as a Bacteroides sp. and shown to recover phages from multiple sources of sewage produced in Hawaii at high concentrations (5.2-7.3 × 10⁵ PFU/100 mL). These Bacteroides phages were considered as potential markers of sewage because they also survived for three days in fresh stream water and two days in marine water. Water samples from Hawaii’s coastal swimming beaches and harbors, which were known to be contaminated with discharges from streams, were shown to contain moderate (20-187 CFU/100 mL) to elevated (173-816 CFU/100 mL) concentrations of enterococci. These same samples contained undetectable levels (<10 PFU/100 mL) of F+ coliphage and Bacteroides phages and provided evidence to suggest that these enterococci may not necessarily be associated with the presence of raw sewage. These results support previous conclusions that discharges from streams are the major sources of enterococci in coastal waters of Hawaii and the most likely source of these enterococci is from environmental soil rather than from sewage.     

Third-order nonlinear optical characteristics of bulk film effect on regioregular poly(3-dodecylthiophene) thin films fabricated by the drop-casting method

We report the morphologies and the bulk film effect on regioregular poly(3-dodecylthiophene) [RR-P3DDT] thin films fabricated with different concentrations (0.1, 0.2, 0.4 wt%) by drop-casting method using chloroform as a solvent and fused quartz glass as substrate. The measured thicknesses of the films were 220, 340 and 600 nm. The thin films were characterized by UV–Vis spectra and X-ray diffraction. The surface morphology of the thin film (600 nm) was analyzed using atomic force microscopy. The third order nonlinear susceptibility characteristics of the films were measured using Maker fringes method. These films exhibit efficient THG bulk effect with a maximum χ³ value of 1.41 × 10^?10 esu obtained for 0.4 wt% concentration of RR-P3DDT revealing that this material is potentially suited for fabricating optical limiters.