The accelerating effect of additives on radiation-induced graft polymerization : final report /

"Category No. UC-4 ; Chemistry ; TID-4500."

Analyzing the Effect of Soiling on the Performance of a Photovoltaic System of Different Module Technologies in Kalkbult, South Africa

The fact that most of the large scale solar PV plants are built in arid and semi-arid areas where land availability and solar radiation is high, it is expected the performance of the PV plants in such locations will be affected significantly due to high cell temperature as well as due to soiling. Therefore, it is essential to study how the different PV module technologies will perform in such geographical locations to ensure a consistent and reliable power delivery over the lifetime of the PV power plants. As soiling is strongly dependent on the climatic conditions of a particular location a test station, consisted of about 24 PV modules and a well-equipped weather station, was built within the fences of Scatec’s 75 MW Kalkbult solar PV plant in South Africa. This study was performed to a better understand the effect of soiling by comparing the relative power generation by the cleaned modules to the un-cleaned modules. Such knowledge can enable more quantitative evaluations of the cleaning strategies that are going to be implemented in bigger solar PV power plants. The data collected and recorded from the test station has been analyzed at IFE, Norway using a MatLab script written for this thesis project. This thesis work has been done at IFE, Norway in collaboration with Stellenbosch University in South Africa and Scatec Solar a Norwegian independent power producer company. Generally for the polycrystalline modules it is found that the average temperature corrected efficiency during the period of the experiment has been 15.00±0.08 % and for the thin film-CdTe with ARC is 11.52% and for the thin film without ARC is about 11.13% with standard uncertainty of ±0.01 %. Besides, by comparing the initial relative average efficiency of the polycrystalline-Si modules when all the modules have been cleaned for the first time and the final relative efficiency; after the last cleaning schedule which is when all the reference modules E, F, G, and H have been cleaned for the last time it is found that poly3 performs 2 % and 3 % better than poly1 and poly16 respectively, poly13 performs 1 % better than poly15 as well as poly5 and poly12 performs 1 % and 2 % better than poly10 respectively. Besides, poly5 and poly12 performs a 9 % and 11 % better than poly7. Furthermore, there is no change in performance between poly6 and poly9 as well as poly4 and poly15. However, the increase in performance of poly3 to poly1, poly13 to poly15 as well as poly5 and poly12 to poly10 is insignificant. In addition, it is found that TF22 perform 7% better than the reference un-cleaned module TF24 and similarly; TF21 performs 7% higher than TF23. Furthermore, modules with ARC glass (TF17, TF18, TF19, and TF20) shows that cleaning the modules with only distilled water (TF19) or dry-cleaned after cleaned with distilled water(TF20) decreases the performance of the modules by 5 % and 4 % comparing to its respective reference uncleanedmodules TF17 and TF18 respectively.

The effect of metamictization on the Raman spectroscopy of the uranyl titanate mineral davidite (La,Ce)(Y,U,Fe2+)(Ti,Fe3+)20(O,OH)38

Raman spectra of the uranyl titanate mineral davidite-(La) (La,Ce)(Y,U,Fe2+)(Ti,Fe3+)20(O,OH)38 were analysed and related to the mineral structure. Observed bands are attributed to the TiO and (UO2)2+ stretching and bending vibrations, U-OH bending vibrations, H2O and (OH)- stretching, bending and libration modes. U-O bond lengths in uranyls and O-H…O bond lengths are calculated from the wavenumbers assigned to the stretching vibrations. Raman bands of davidite-(La) are in harmony with those of the uranyl oxyhydroxides. The mineral davidite-(La) is metamict as is evidenced by the intensity of the UO stretching and bending modes being of lower intensity than expected and with bands that are significantly broader.

The effect of endophyte on the performance of irrigated perennial ryegrasses in subtropical Australia

The effect of fungal endophyte (Neotyphodium lolii) infection on the performance of perennial ryegrass (Lolium perenne) growing under irrigation in a subtropical environment was investigated. Seed of 4 cultivars, infected with standard (common toxic or wild-type) endophyte or the novel endophyte AR1, or free of endophyte (Nil), was sown in pure swards, which were fertilised with 50 kg N/ha.month. Seasonal and total yield, persistence, and rust susceptibility were assessed over 3 years, along with details of the presence of endophyte and alkaloids in plant shoots. Endophyte occurrence in tillers in both the standard and AR1 treatments was above 95% for Bronsyn and Impact throughout and rose to that level in Samson by the end of the second year. Meridian AR1 only reached 93% while, in the standard treatment, the endophyte had mostly died before sowing. Nil Zendophyte treatments carried an average of ?0.6% infection throughout. Infection of the standard endophyte was associated with increased dry matter (DM) yields in all 3 years compared with no endophyte. AR1 also significantly increased yields in the second and third years. Over the full 3 years, standard and AR1 increased yields by 18% and 11%, respectively. Infection with both endophytes was associated with increased yields in all 4 seasons, the effects increasing in intensity over time. There was 27% better persistence in standard infected plants compared with Nil at the end of the first year, increasing to 198% by the end of the experiment, while for AR1 the improvements were 20 and 134%, respectively. The effect of endophyte on crown rust (Puccinia coronata) infection was inconsistent, with endophyte increasing rust damage on one occasion and reducing it on another. Cultivar differences in rust infection were greater than endophyte effects. Plants infected with the AR1 endophyte had no detectable ergovaline or lolitrem B in leaf, pseudostem, or dead tissue. In standard infected plants, ergovaline and lolitrem B were highest in pseudostem and considerably lower in leaf. Dead tissue had very low or no detectable ergovaline but high lolitrem B concentrations. Peramine concentration was high and at similar levels in leaf and pseudostem, but not detectable in dead material. Concentration was similar in both AR1 and standard infected plants. Endophyte presence appeared to have a similar effect in the subtropics as has been demonstrated in temperate areas, in terms of improving yields and persistence and increasing tolerance of plants to stress factors.

The Effect of Framing on Layoff Decisions: Are More-Experienced Managers More Rational? Does Computerized Data Make Any Difference?

[Excerpt] The effects of framing on decisions has been widely studied, producing research that suggests individuals respond to framing in predictable and fairly consistent ways (Bazerman, 1984, 1990; Tversky & Kahneman, 1986; Thaler, 1980). The essential finding from this body of research is that "individuals treat risks concerning perceived gains (for example, saving jobs and plants) differently from risks concerning perceived losses (losing jobs and plants)" (Bazerman, 1990, pp. 49-50). Specifically, individuals tend to avoid risks concerning gains, and seek risks concerning losses.

The effect of lycopene on the PI3K/Akt signalling pathway in prostate cancer

Prostate cancer is common in men with very high mortality which is one of leading causes of cancer-related deaths in men. The main treatment approaches for metastasized prostate cancer are androgen deprivation and chemotherapeutic agents. Although there are initial responses to castration, the resistance to the treatment will eventually occur, leading to castration-resistant prostate cancer. The common chemotherapeutic agents for the treatment of prostate cancer are docetaxel and taxane but outcomes of using these drugs have not been satisfactory. Therefore, it is necessary to find better treatment approaches for prostate cancer and to search for compounds that are effective in prostate cancer prevention. Lycopene extracted from tomato and other fruits or plants such as Gac, watermelon, pink grapefruit, pink guava, red carrot and papaya has been shown to be effective on prostate cancer prevention and treatment. The advantage of the application of lycopene for its anti-prostate cancer activity is that lycopene can reach much higher concentration in prostate tissue than other tissues. In this review, the effect of lycopene on PI3K/Akt pathway is summarised, which could be one of major mechanisms for anti-cancer activity of lycopene.

In response: UV–vis light transmittance through tinted contact lenses and the effect of color on values

In the study, we used the Agilent 8453 spectrophotometer (which is equipped with a limiting aperture that restricts the light beam to the central 5 mm of the contact lens), to measure the transmittance of various coloured contact lenses including the one Day Acuvue define manufactured by Johnson and Johnson which the authors represent. We measured the instrument baseline before the transmittance spectra of lenses were tested. The values of lens transmittances were thus the difference between baseline and lens measurement at each time. The transmittance measurements were obtained at 0.5 nm intervals, from 200 to 700 nm after a soak in saline to remove the influence of any surface active agents within the packaging products. The technique used in our study was not very different from how other research studies [2], [3], [4], [5] and [6] have measured the spectra transmittances of contact lenses...

Evaluation of polymeric nanomedicines targeted to PSMA: Effect of ligand on targeting efficiency

Targeted nanomedicines offer a strategy for greatly enhancing accumulation of a therapeutic within a specific tissue in animals. In this study, we report on the comparative targeting efficiency toward prostate-specific membrane antigen (PSMA) of a number of different ligands that are covalently attached by the same chemistry to a polymeric nanocarrier. The targeting ligands included a small molecule (glutamate urea), a peptide ligand, and a monoclonal antibody (J591). A hyperbranched polymer (HBP) was utilized as the nanocarrier and contained a fluorophore for tracking/analysis, whereas the pendant functional chain-ends provided a handle for ligand conjugation. Targeting efficiency of each ligand was assessed in vitro using flow cytometry and confocal microscopy to compare degree of binding and internalization of the HBPs by human prostate cancer (PCa) cell lines with different PSMA expression status (PC3-PIP (PSMA+) and PC3-FLU (PSMA−). The peptide ligand was further investigated in vivo, in which BALB/c nude mice bearing subcutaneous PC3-PIP and PC3-FLU PCa tumors were injected intravenously with the HBP-peptide conjugate and assessed by fluorescence imaging. Enhanced accumulation in the tumor tissue of PC3-PIP compared to PC3-FLU highlighted the applicability of this system as a future imaging and therapeutic delivery vehicle.

Effect of disorder on the exponent in the coherence region in high temperature superconductors

Effect of disorder on the electrical resistance near the superconducting transition temperature in the paracoherence region of high temperature YBa2CU3O7-delta (YBCO) thin film superconductor is reported. For this, c-axis oriented YBa2Cu3O7-delta thin films having superconducting transition width varying between 0.27 K and 6 K were deposited using laser ablation and high pressure oxygen sputtering techniques. Disorder in these films was further created by using 100 MeV oxygen and 200 MeV silver ions with varying fluences. It is observed that the critical exponent in the paracoherence region for films with high transition temperature and small transition width is in agreement with the theoretically predicted value (gamma = 1.33) and is not affected by disorder, while for films with lower transition temperature and larger transition width the value of exponent is much larger as compared to that theoretically predicted and it varies from sample to sample and usually changes with disorder induced by radiation. This difference in the behaviour of the exponent has been explained on the basis of differences in the strength of weak links and the transition between temperatures T. and T, is interpreted as a percolation like transition with disorder. (c) 2006 Elsevier B.V. All rights reserved.

Effect of p53 on lung carcinoma cells irradiated by carbon ions or X-rays

The study is to investigate the feasibility and advantages of heavy ion beams on radiotherapy. The cellular cycle and apoptosis, cell reproductive death and p53 expression evaluated with flow cytometry, clonogenic survival assays and Western blot analysis were examined in lung carcinoma cells after exposure to 89.63 MeV/u carbon ion and 6 MV X-ray irradiations, respectively. The results showed that the number colonyforming assay of A549 was higher than that of H1299 cells in two radiation groups; A549 cellular cycle was arrested in G(2)/M in 12 It and the percentage of apoptosis ascended at each time point of carbon ion radiation with doses, the expression of p53 upregulated with doses exposed to X-ray or carbon ion. The cell number in G(2)/M of H1299 and apoptosis were increasing at all time points with doses in C-12(6+) ion irradiation group. The results suggested that the effects of carbon ions or X rays irradiation on lung carcinoma cells were different, C-12(6+) ion irradiation could have more effect on upregulating the expression of p53 than X-ray, and the upregulated expression of p53 might produce the cellular cycle G(2)/M arrested, apoptosis increasing; and p53 gene might affect the lung cancer cells radiosensitivity.

Carbon flow in an upland grassland: effect of liming on the flux of recently photosynthesized carbon to rhizosphere soil

The effect of liming on the flow of recently photosynthesized carbon to rhizosphere soil was studied using (CO2)-C-13 pulse labelling, in an upland grassland ecosystem in Scotland. The use of C-13 enabled detection, in the field, of the effect of a 4-year liming period of selected soil plots on C allocation from plant biomass to soil, in comparison with unlimed plots. Photosynthetic rates and carbon turnover were higher in plants grown in limed soils than in those from unlimed plots. Higher delta(13)C% values were detected in shoots from limed plants than in those from unlimed plants in samples clipped within 15 days of the end of pulse labelling. Analysis of the aboveground plant production corresponding to the 4-year period of liming indicated that the standing biomass was higher in plots that received lime. Lower delta(13)C% values in limed roots compared with unlimed roots were found, whereas no significant difference was detected between soil samples. Extrapolation of our results indicated that more C has been lost through the soil than has been gained via photosynthetic assimilation because of pasture liming in Scotland during the period 1990-1998. However, the uncertainty associated with such extrapolation based on this single study is high and these estimates are provided only to set our findings in the broader context of national soil carbon emissions.

Effect of light on ex situ production of symbiotic corals

The increasing interest in coral culture for biotechnological applications, to supply the marine aquarium trade, or for reef restoration programs, has prompted researchers to optimize coral culture protocols, with emphasis to ex situ production. When cultured ex situ, the growth performance of corals can be influenced by several physical, chemical and biological parameters. For corals harbouring zooxanthellae, light is one of such key factors, as it can influence the photosynthetic performance of these endosymbionts, as well as coral physiology, survival and growth. The economic feasibility of ex situ coral aquaculture is strongly dependent on production costs, namely those associated with the energetic needs directly resulting from the use of artificial lighting systems. In the present study we developed a versatile modular culture system for experimental coral production ex situ, assembled solely using materials and equipment readily available from suppliers all over the world; this approach allows researchers from different institutions to perform truly replicated experimental set-ups, with the possibility to directly compare experimental results. Afterwards, we aimed to evaluate the effect of contrasting Photosynthetically Active Radiation (PAR) levels, and light spectra emission on zooxanthellae photochemical performance, through the evaluation of the maximum quantum yield of PSII (Fv/Fm) (monitored non-invasively and non-destructively through Pulse Amplitude Modulation fluorometry, PAM), chlorophyll a content (also determined non-destructively by using the spectral reflectance index Normalized Difference Vegetation Index, NDVI), photosynthetic and accessory pigments, number of zooxanthellae, coral survival and growth. We studied two soft coral species, Sarcophyton cf. glaucum and Sinularia flexibilis, as they are good representatives of two of the most specious genera in family Alcyoniidae, which include several species with interest for biotechnological applications, as well as for the marine aquarium trade; we also studied two commercially important scleractinian corals: Acropora formosa and Stylophora pistillata. We used different light sources: hydrargyrum quartz iodide (HQI) lamps with different light color temperatures, T5 fluorescent lamps, Light Emitting Plasma (LEP) and Light Emitting Diode (LED). The results achieved revealed that keeping S. flexibilis fragments under the same light conditions as their mother colonies seems to be photobiologically acceptable for a short-term husbandry, notwithstanding the fact that they can be successfully stocked at lower PAR intensities. We also proved that low PAR intensities are suitable to support the ex situ culture S. cf. glaucum in captivity at lower production costs, since the survival recorded during the experiment was 100%, the physiological wellness of coral fragments was evidenced, and we did not detect significant differences in coral growth. Finally, we concluded that blue light sources, such as LED lighting, allow a higher growth for A. formosa and S. pistillata, and promote significant differences on microstructure organization and macrostructure morphometry in coral skeletons; these findings may have potential applications as bone graft substitutes for veterinary and/or other medical uses. Thus, LED technology seems to be a promising option for scleractinian corals aquaculture ex situ.

Radiation-induced changes in the export of photoassimilated carbon /|nBarry Jess Shelp. -- 260 0 St. Catharines, [Ont. : s. n.],

Low levels of ionizing radiation induce two translocation responses in soybean: a reduction in photoassimilate export from leaves and a change in the distribution pattern of exported photoassimilate within the plant. In this investigation these responses have been further studied specifically to ascertain the site of radiation damage and to better understand the physiological responses observed. Experimentally the primary data was obtained from studies in which a mature trifoliate leaf of a young soybean plant (Glycine ~ L. cultivar Harosoy '63) is isolated in a closed transparent chamber and allowed to photoassimilate 14C02 for 15 minutes. This is followed by an additional 45 ~_il'1;ute period before the plant is sectl.o ne d an d 14 C-ra dl' oactl.v.l ty d eterml. ne d'l n a 11 parts. Such 14c data provides one with the magnitude and distribution pattern of translocation. Further analyses were conducted to determine the relative levels of the major photosynthetic products using the techniques of paper chromatography and autoradiography. Since differences between control and irradiated P 1 ants were not 0 b serve d l' n t h e par tl't"lo nlng 0 f 14 C between the 80% ethanol-soluble and -insoluble fractions 14 or in the relative amounts of C-products of photosynthesis, the reduction in export in irradiated plants is not likely due to reduced availability of translocatable materials. Data presented in this thesis shows that photoassimilate export was not affected by gamma radiation until a threshold dose between 2.0 and 3.0 krads was reached. It was also observed that radiation-induced damage to the export process was capable of recovery in a period of 1 to 2 hours provided high light intensity was supplied. In contrast, the distribution pattern was shown to be extremely radiosensitive with a low threshold dose between .25 and .49 krads. Although this process was also capable of recovery,lt" occurred much earlier and was followed by a secondary effect which lasted at least for the duration of the experiments. The data presented in this thesis is interpreted to suggest that the sites of radiation action for the two translocation responses are different. In regards to photoassimilate export, the site of action of ionizing radiation is the leaf, quite possibly the process of photophosphorylation which may provide energy directly for phloem loading and for membrane integrity of the phloem tissue* In regards to the pattern of distribution of exported photoassimilate, the site is likely the apical sink, possibly the result of changes of levels of endogenous hormones. By the selection of radiation exposure dose and time post-irradiation, it is possible to affect independently these two processes suggesting that each may be regulated independent of the other and involves a distinct site.

The effect of environment on endosperm cell-wall development in Triticum aestivum during grain filling: an infrared spectroscopic imaging study

One of the major factors contributing to the failure of new wheat varieties is seasonal variability in end-use quality. Consequently, it is important to produce varieties which are robust and stable over a range of environmental conditions. Recently developed sample preparation methods have allowed the application of FT-IR spectroscopic imaging methods to the analysis of wheat endosperm cell wall composition, allowing the spatial distribution of structural components to be determined without the limitations of conventional chemical analysis. The advantages of the methods, described in this paper, are that they determine the composition of endosperm cell walls in situ and with minimal modification during preparation. Two bread-making wheat cultivars, Spark and Rialto, were selected to determine the impact of environmental conditions on the cell-wall composition of the starchy endosperm of the developing and mature grain, focusing on the period of grain filling (starting at about 14 days after anthesis). Studies carried out over two successive seasons show that the structure of the arabinoxylans in the endosperm cell walls changes from a highly branched form to a less branched form. Furthermore, during development the rate of restructuring was faster when the plants were grown at higher temperature with restricted water availability from 14 days after anthesis with differences in the rate of restructuring occurring between the two cultivars.