The Clouding Phenomenon for Anionic Sodium Dodecyl Sulfate + Quaternary Bromides in Polar Nonaqueous-Water-Mixed Solvents

Aqueous sodium dodecyl sulfate (SDS) solutions show clouding in the presence of tetra-n-butylammonium bromide (TBAB) and tetra-n-butylphosphonium bromide (TBPB). In this study, we report the effect of various volume percents of different polar nonaqueous solvents (acetonitrile, AN; dimethylsulfoxide, DMSO; methyl ethylene glycol ether, MC; formamide, FA; ethylene glycol, EG) on the clouding behavior of SDS + quaternary bromide (TBAB or TBPB) systems. The cloud point (CP) was found to decrease with initial increase in the volume percent of the above solvents in mixtures (with water). After a minimum in CP vs. volume percent plots, further increase in the volume percent caused an increase in the CP, followed by a near constant region. The data have been discussed on the basis of the effect of the above solvents on the two types of water present in the system: hydrated water and bulk water. As AN had shown a gradual decrease in the CP to a larger volume percent, it was chosen for detailed studies. Compared to TBAB, TBPB has diminished the effect of AN on CP increase due to its bigger size. The limited CMC data also run parallel to CP results.

Effect of size of fly ash particle on enhancement of mullite content and glass formation

Quartz is widely replaced by fly ash in traditional porcelain composite. Increased strength and stability of the fly ash-mixed composite depends on the quantity and crystallinity of the mullite phase in the fly ash. Our aim in this investigation is to increase the formation of mullite in nanocrystalline form and study the effect of temperature. Quantitative estimation of mullite and residual quartz content were done by X-ray diffraction (XRD) and nanostructure and crystallization were studied using differential thermal analysis (DTA), field effect scanning electron microscopy (FESEM), XRD and Fourier transform infrared (FTIR) spectroscopy. The results show that fly ash sieved through 250 holes/cm² mesh contain more mullite initially and growth of mullite as well as glass formation was faster in this sample compared to coarse fly ash. The maximum mullite in these samples was formed at 1600°C. Transformation of quartz and cristobalite phases into glassy phase was also faster for smaller particle sizes of fly ash.     

Effect of polyaniline concentration on the photoconversion efficiency of nano-TiO<Subscript>2</Subscript> based dye sensitized solar cells

Extensive research have been made in improving the dye sensitized solar cells (DSSC) performance by designing, tailoring and enhancing the photoconversion properties of the matrix. The approaches used are material synthesis, dye permutation combinations, use of natural extracts or using several sensitizers. The polymers are also being explored in this regards in their pristine or composite forms. Therefore, in this study an attempt is made to synthesize a mesoporous polyaniline–titanium dioxide (PANI–TiO₂) nanocomposites with one pot synthesis approach at different concentrations of PANI (0.3–0.7 ml). Titanium isopropoxide was used as precursor for TiO₂ with aniline and the material was synthesized at ice bath temperature. Morphological observations showed that the composite is a mesoporous material with tubular structure where TiO₂ particles are seen entrapped in the polymer matrix and found that intercalation can be tailored with PANI concentration. Structural, functional and optical characterization indicate anatase phase of TiO₂, with several functional bands that can help in dye interaction and broad absorption bands within visible region. The photocurrent-voltage response was measured with simulated light and source-meter. It is interesting to note that increasing PANI concentration enhances the mesoporous structure and hence increases the dye loading capacity and photoconductivity of the material. The efficiency increased by about 22 % with addition of 0.5 ml of PANI from 0.3 ml. The proposed study has indicated that such material have the potential to be used for DSSC fabrication with which the device performance can further be increased to a better levels.     

Spatial planning and climate change

Wind energy development is expanding. Preparations for wind farms include environmental impact assessments, specifically with visual impact assessments (VIAs). Often using simulated photographs, VIAs depict the post-development landscape appearance with new wind energy structures. This Ontario case study compares simulated photographs submitted as part of a VIA with post-development conditions. Simulations were judged for accuracy in turbine number, height, diameter, and location, and adequacy in representation of built conditions. Simulations were partially representative of postdevelopment conditions, yet commonly under-represented turbine number and size in different locations than they were built. Simulation frames were too narrow to adequately represent human vision and simulations under-estimated how many wind turbines were visible from a single landscape position. Outcomes suggest that visual simulations can lack accuracy or representativeness, misleading the public. Adopting province-wide VIA criteria and increasing adherence to visual simulation guidance may be necessary to improve the accuracy and representativeness of VIA content.     

Bacteriocin‐capped silver nanoparticles for enhanced antimicrobial efficacy against food pathogens

Bacteriocins produced by lactic acid bacteria are safer alternatives to the more popularly used chemical preservatives which exhibit several adverse effects. The bacteriocins have an advantage of being efficient in controlling food pathogens without possessing any side‐effects. However, the bacteriocins have a limitation of exhibiting a narrow antimicrobial spectrum and having a high‐dosage requirement. With an aim to combat these limitations, the present study involved the biosynthesis of bacteriocin‐capped nanoparticles, using two bacteriocins (Bac4463 and Bac22) extracted and purified from Lactobacillus strains. Nanoconjugates synthesised at optimum conditions were characterized using various physico‐chemical techniques. The interaction of bacteriocin‐capped silver nanoparticles with the pathogenic bacteria was observed using scanning electron microscopy, wherein the deformed and elongated cells were clearly visible. In vitro antimicrobial efficacy of both Bac4463‐capped silver nanoparticles and Bac22‐capped silver nanoparticles against different food pathogens was observed to be enhanced in comparison to the antimicrobial activity of bacteriocins alone. Minimum inhibitory concentration was observed to be as low as 8 μg/ml for Bac4463‐capped silver nanoparticles against Staphylococcus aureus, and 2 μg/ml for Bac22‐capped silver nanoparticles against Shigella flexneri. This study, therefore, recommends the use of bacteriocin‐capped nanoparticles as food preservatives to control the growth of food spoiling bacteria.Inspec keywords: preservatives, elongation, food safety, silver, biotechnology, antibacterial activity, food preservation, nanoparticles, nanofabrication, food products, scanning electron microscopy, microorganismsOther keywords: bacteriocins, chemical preservatives, food pathogens, bacteriocin‐capped nanoparticles, bacteriocin‐capped silver nanoparticles, Bac4463‐capped silver nanoparticles, Bac22‐capped silver nanoparticles, enhanced antimicrobial efficacy     

Thermophysical Properties of Binary Mixtures of Methanol with Chlorobenzene and Bromobenzene from 293 K to 313 K

Densities and viscosities have been measured for the binary mixtures of methanol with chlorobenzene and with bromobenzene from 293 K to 313 K over the complete composition range. Densities were used to compute the excess molar volume ( , for these binary systems. The results have been discussed in terms of molecular interactions. Furthermore, viscosity results were compared with a corresponding-states model. The average absolute deviation was found to be 1.9 %.     

Antibodies to single-stranded and double-stranded DNA in antinuclear antibody-positive type 1-autoimmune hepatitis

To determine the significance of antibodies to single-stranded (anti-ssDNA) and double-stranded DNA (anti-dsDNA) in antinuclear antibody (ANA)-positive type 1 autoimmune hepatitis, sera from 53 patients were tested by enzyme immunosorbent assay (ELISA) and indirect immunofluorescence using the Crithidia luciliae substrate. Anti-dsDNA were detected in 18 patients (34%) by ELISA and 12 patients (23%) by the Crithidia-based assay. Twenty patients with anti-dsDNA by either assay (38%) had higher serum levels of immunoglobulin G (3971 +/- 270 mg/dL vs. 3201 +/- 247 mg/dL, P = .05) than seronegative patients. They also had human leukocyte antigen (HLA) DR4 more commonly than other patients (83% vs. 41%, P = .006) and normal subjects (83% vs. 30%, P = .00007). In contrast to patients seropositive by the Crithidia-based assay, those seropositive by ELISA failed corticosteroid therapy more commonly (24% vs. 3%, P = .04). Anti-ssDNA were found in 45 patients (85%) and they did not distinguish patients with different clinical features or outcomes. We conclude that anti-dsDNA are common in ANA-positive type 1 autoimmune hepatitis. HLA DR4 is associated with their production, and seropositivity by ELISA characterizes patients who have a poorer immediate response to corticosteroid treatment. Anti-ssDNA are common but they do not have important clinical implications.     

Different classes of proteoglycans contribute to the attachment of Borrelia burgdorferi to cultured endothelial and brain cells

PURPOSE: To compare failure-free survival (FFS) and overall survival (OS) for patients with metastatic breast cancer treated with the gonadotropin-releasing hormone (GN-RH) agonist, goserelin versus surgical ovariectomy. PATIENTS AND METHODS: Between August 1, 1987 and July 15, 1995 138 (136 eligible) premenopausal patients with estrogen receptor (ER)- and/or progesterone receptor (PgR)-positive metastatic breast cancer were entered by the Southwest Oncology Group (SWOG), North Central Cancer Treatment Group (NCCTG), and Eastern Cooperative Oncology Group (ECOG). Prior chemotherapy or hormone therapy for metastatic disease was not allowed. Patients were randomly assigned to goserelin (3.6 mg subcutaneously every 4 weeks; (n = 69) versus surgical ovariectomy (n = 67). The study was initially designed as an equivalence trial with 80% power to rule out a 50% improvement in survival due to ovariectomy. However, accrual was slow and the study was terminated early, which resulted in a final power of 60% for the alternative hypothesis of equal survival distributions. RESULTS: FFS and OS were similar for goserelin and ovariectomy. The goserelin/ovariectomy death hazards ratio was .80 and the associated 95% confidence interval (CI) was .53 to 1.20. The test of 50% improvement in survival due to ovariectomy was rejected at P = .006. Goserelin lowered serum estradiol to postmenopausal levels. Hot flashes (75% v 46%) and tumor flare (16% v 3%) were more common with goserelin. CONCLUSION: Goserelin and ovariectomy resulted in similar FFS and OS. We can rule out a moderate advantage for ovariectomy. Goserelin was safe and well tolerated.     

Examining the relationship between free recall and immediate serial recall: The effect of concurrent task performance.

In 3 experiments, participants saw lists of 16 words for free recall with or without a 6-digit immediate serial recall (ISR) task after each word. Free recall was performed under standard visual silent and spoken-aloud conditions (Experiment 1), overt rehearsal conditions (Experiment 2), and fixed rehearsal conditions (Experiment 3). The authors found that in each experiment, there was no effect of ISR on the magnitude of the recency effect, but interleaved ISR disrupted free recall of those words that would otherwise be rehearsed. The authors conclude that ISR and recency cannot both be outputs from a unitary limited-capacity short-term memory store and discuss the possibility that the process of rehearsal may be common to both tasks. (PsycINFO Database Record (c) 2010 APA, all rights reserved)