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Stronger Intensity (stronger + intensity)
Selected AbstractsEffects of Zinc(II) on the Luminescence of Europium(III) in Complexes Containing , -Diketone and Schiff BasesHELVETICA CHIMICA ACTA, Issue 11 2009Yuko Hasegawa Abstract The UV, excitation, and luminescence spectra of tris(pivaloyltrifluoroacetonato)europium(III) ([Eu(pta)3]; Hpta=1,1,1-trifluoro-5,5-dimethylhexane-2,4-dione=HA) were measured in the presence of bis(salicylidene)trimethylenediamine (H2saltn), bis[5-(tert- butyl)salicylidene]trimethylenediamine (H2(tBu)saltn), or bis(salicylidene)cyclohexane-1,2-diyldiamine (H2salchn), and the corresponding ZnII complexes [ZnB] (B=Schiff base). The excitation and luminescence spectra of the solution containing [Eu(pta)3] and [Zn(salchn)] exhibited much stronger intensities than those of solutions containing the other [ZnB] complexes. The introduction of a tBu group into the Schiff base was not effective in sensitizing the luminescence of [Eu(pta)3]. The luminescence spectrum of [ZnB] showed a band around 450,nm. The intensity decreased in the presence of [Eu(pta)3], reflecting complexation between [Eu(pta)3] and [ZnB]. On the basis of the change in intensity against the concentration of [ZnB], stability constants were determined for [Eu(pta)3Zn(saltn)], [Eu(pta)3Zn{(tBu)saltn}], and [Eu(pta)3Zn(salchn)] as 4.13, 4.9 and 5.56, respectively (log,, where =[[Eu(pta)3ZnB]]([[Eu(pta)3]][[ZnB]]),1). The quantum yields of these binuclear complexes were determined as 0.15, 0.11, and 0.035, although [Eu(pta)3Zn(salchn)] revealed the strongest luminescence at 613,nm. The results of X-ray diffraction analysis for [Eu(pta)3Zn(saltn)] showed that ZnII had a coordination number of five and was bridged with EuIII by three donor O-atoms, i.e., two from the salicylidene moieties and one from the ketonato group pta. [source] Rapid determination of rice seed vigour by spontaneous chemiluminescence and singlet oxygen generation during early imbibitionLUMINESCENCE: THE JOURNAL OF BIOLOGICAL AND CHEMICAL LUMINESCENCE, Issue 1 2003Wenli Chen Abstract Using a highly sensitive single photon counter, a spontaneous chemiluminescence (CL) study on rice (Oryza sativa L.) seeds stored in different years was carried out. We first observed that the degree of ageing in rice seeds was related to the intensity of spontaneous CL during early imbibition (0,30 min). Rice seeds stored for a shorter time had a stronger intensity of CL in early imbibition. The germination rate of rice seeds showed an obvious positive correlation with the intensity of spontaneous CL. Singlet oxygen (1O2) in rice seeds during early imbibition was investigated by a CL method using a cypridina luciferin analogue, 2-methyl-6-(p -methoxyphenyl)-3,7-dihydroimidazo [1,2,] pyrazin-3-one (MCLA), as a selective CL probe. Additional experimental evidence for the formation of 1O2 came from the quenching effect of sodium azide (NaN3) on MCLA-mediated rice seeds' CL. Analysis based on the experimental results demonstrated that spontaneous CL in rice seeds during early imbibition was mainly contributed by singlet oxygen (1O2). Copyright © 2002 John Wiley & Sons, Ltd. [source] Study of Protoporphyrin IX (PpIX) Pharmacokinetics After Topical Application of 5-Aminolevulinic Acid in Urethral Condylomata Acuminata,PHOTOCHEMISTRY & PHOTOBIOLOGY, Issue 5 2007Xiu-Li Wang The pharmacokinetics of 5-aminolevulinic acid (ALA)-induced protoporphyrin IX (PpIX) in lesions of urethral condylomata acuminata were investigated. Sixty patients (20 to 60 years old, 48 male and 12 female) were divided randomly into five groups and received topic application of different concentrations of ALA solution (0.5%, 1%, 3%, 5% or 10%). Biopsy was performed between 1 and 7 h and specimens were subjected to histological, PpIX fluorescence and human papillomavirus (HPV) DNA typing analyses. Fluorescence examination confirmed that ALA-induced PpIX fluorescence was dominantly distributed in the HPV-infected epidermis. In contrast, only a minimal amount of PpIX fluorescence was detected in the dermis. The maximal fluorescence intensity was detected at 5 h incubation. Higher ALA concentration (e.g. 5% and 10%) produced a stronger intensity. These results suggest that the topical application of 5,10% ALA solution for 3,5 h is the optimal condition for the photodynamic therapy of urethral condylomata acuminata. The selective damage of the condylomata acuminata lesions in the epidermis without damaging the dermis ensures a better control of recurrence and side effects such as ulceration or scarring. DNA typing showed that all patients were positive for low risk-HPV DNA and among them 18.3% of patients harbored high risk-HPV DNA. [source] Fas ligand and tumour counter-attack in colorectal cancer stratified according to microsatellite instability statusTHE JOURNAL OF PATHOLOGY, Issue 1 2003Julie M Michael-Robinson Abstract Expression of membrane-bound Fas ligand (FasL) by colorectal cancer cells may allow the development of an immune-privileged site by eliminating incoming tumour-infiltrating lymphocytes (TILs) in a Fas-mediated counter-attack. Sporadic colorectal cancer can be subdivided into three groups based on the level of DNA microsatellite instability (MSI). High-level MSI (MSI-High) is characterized by the presence of TILs and a favourable prognosis, while microsatellite-stable (MSS) cancers are TIL-deficient and low-level MSI (MSI-Low) is associated with an intermediate TIL density. The purpose of this study was to establish the relationship between MSI status and FasL expression in primary colorectal adenocarcinoma. Using immunohistochemistry and a selected series of 101 cancers previously classified as 31 MSI-High, 30 MSI-Low, and 40 MSS, the present study sought to confirm the hypothesis that increased TIL density in MSI-High cancers is associated with low or absent membrane-bound FasL expression, while increased FasL in MSS cancers allows the killing of host TILs. TUNEL/CD3 double staining was also used to determine whether MSS cancers contain higher numbers of apoptotic TILs in vivo than MSI-High or MSI-Low cancers. Contrary to the initial hypothesis, it was found that MSI-High cancers were associated with higher FasL expression (p = 0.04) and a stronger intensity of FasL staining (p = 0.007). In addition, mucinous carcinomas were independently characterized by increased FasL expression (p = 0.03) and staining intensity (p = 0.0005). Higher FasL expression and staining intensity did not correlate with reduced TIL density or increased numbers of apoptotic TILs. However, consistent with the hypothesis that curtailment of the host anti-tumour immune response contributes to the poor prognosis in MSS cancers, it was found that apoptotic TILs were most abundant in MSS carcinomas and metastatic Dukes' stage C or D tumours (p = 0.004; p = 0.046 respectively). This study therefore suggests that MSS colorectal cancers are killing incoming TILs in an effective tumour counter-attack, but apparently not via membrane-bound FasL. Copyright © 2003 John Wiley & Sons, Ltd. [source] Dachentwässerungen im Zuge geänderter normativer Anforderungen und sich ändernder klimatischer Einwirkungen , eine Planungsaufgabe?BAUPHYSIK, Issue 2 2008Jörg Röder Dr.-Ing. Die Dach- und Gebäudeentwässerung soll für den schadenfreien Abfluss des Regenwassers sorgen. Die planmäßige Dachentwässerung wird dabei "nur" für einen mittleren Regen ausgelegt. Schäden durch stärkere Regenereignisse sollen vermieden werden, indem die Möglichkeit einer Notentwässerung vorgesehen wird. Die Notentwässerung und die Sicherstellung der Funktionstüchtigkeit der Dachentwässerung durch eine regelmäßige Wartung stellen die Hauptanforderungen an Dach- und Gebäudeentwässerungen dar. Die Planung und Bemessung von Rinnen und Fallleitungen erfolgt mit der neuen Normengeneration erstmals unter Verwendung hydraulischer Bemessungsgrundlagen und statistisch abgesicherter Regenspenden. Dennoch zeigen Fallbeispiele, dass der Planung und Bemessung von Dach- und Gebäudeentwässerungen zu wenig Aufmerksamkeit geschenkt wird. Die Folge sind nicht selten Wasserschäden an der Konstruktion. Eine Analyse der Bemessungsverfahren verdeutlicht, dass auch in diesem sensiblen Bereich der Gebäudekonstruktion , im Gegensatz zur statischen Bemessung von Bauteilen , i. d. R. keine Sicherheiten vorgesehen sind. Diese wären jedoch im Zuge sich abzeic hnender Klimaveränderungen u. a. zur Vermeidung von Überbeanspruchungen und Schäden durchaus sinnvoll. Roof drainage in the course of changed regulation require-ments and changed climatic influences , a planning task? The roof and building drainage is supposed to take over the flaw-less drain of rain water. Still, the roof drainage as planned is "only" designed for a rain of medium intensity. In order to prevent damages through rain of stronger intensity the possibility of an emergency drainage will be planned. The emergency drainage and the ensured roof drainage by regular maintenance are the main drainage requirements. With the new regulation generation, planning and structural design of gutters and fall pipes are first done using basis for assessment of hydraulic nature and statistically backed up rain fall data. Nevertheless, case studies show that there is not enough attention given to the planning and design of roof and building drainage. Not uncommon, the result is water damage to the structure. An analysis of the design method shows that even in this sensitive field of building construction , in opposition to static dimensioning of components , there are usually no safeties planned. However, on the tide of the evolving climatic changes, this would make sense inter alia to prevent overloading and damages. [source] | ||||||||||