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排序方式: 共有301条查询结果,搜索用时 31 毫秒
211.
Elena de las Heras Ester Boix-Garriga Francesca Bryden Montserrat Agut Margarita Mora M. Lluïsa Sagristá Ross W. Boyle Norbert Lange Santi Nonell 《Photochemistry and photobiology》2020,96(3):570-580
Active targeting strategies are currently being extensively investigated in order to enhance the selectivity of photodynamic therapy. The aim of the present research was to evaluate whether the external decoration of nanopolymeric carriers with targeting peptides could add more value to a photosensitizer formulation and increase antitumor therapeutic efficacy and selectivity. To this end, we assessed PLGA-PLA-PEG nanoparticles (NPs) covalently attached to a hydrophilic photosensitizer 5-[4-azidophenyl]-10,15,20-tri-(N-methyl-4-pyridinium)porphyrinato zinc (II) trichloride (ZnTriMPyP) and also to c(RGDfK) peptides, in order to target αvβ3 integrin-expressing cells. In vitro phototoxicity investigations showed that the ZnTriMPyP-PLGA-PLA-PEG-c(RGDfK) nanosystem is effective at submicromolar concentrations, is devoid of dark toxicity, successfully targets αvβ3 integrin-expressing cells and is 10-fold more potent than related nanosystems where the PS is occluded instead of covalently bound. 相似文献
212.
John M. Boyle Jr 《Journal of sound and vibration》2006,289(3):632-655
Next-generation, high track-density linear tape drives will require improved tape guiding and dimensional stability in order to achieve better performance and higher storage capacities. Drive vibrations, tape degradation, debris formation, and tape guiding all contribute to unwanted lateral tape motion (LTM), which can lead to track-misregistration errors during reading of the tape. Understanding the nature of LTM is of prime interest. A nonlinear vibration model of a tape-guide system with vibro-impact is presented in this study. The guides are modeled as rigid constraints, while the reels are modeled as clamped ends. Free vibration (due to initial velocity) and forced vibration (due to moving boundaries) were performed for various test cases to determine the effect of tape tension and thickness, tape-guide separation distance, reel tilt amplitude, and tape speed. The model results are compared to actual experimental LTM data, though with the absence of tape damping and tape-guide frictional forces in the model, only limited comparisons may be made. 相似文献
213.
Grant A. Boyle Thavendran Govender Hendrik G. Kruger Glenn E. M. Maguire Tricia Naicker 《Structural chemistry》2008,19(3):429-434
The complete NMR elucidation of three novel pentacycloundecane (PCU)-derived ligands is reported. 2D NMR techniques are used
to overcome the problem of major overlapping of methine signals on the cage skeleton. The compounds were synthesized as potential
ligands to be used in asymmetric catalysis. They represent the first instance where aromatic moieties have been attached directly
to the cage skeleton using lithiation techniques. The X-ray crystal structure of one of the ligands was obtained. The X-ray
structure was helpful in determining the potential NOESY interactions within the set of molecules. For the other ligands a
high level Density Functional Theory (DFT) optimization was performed [B3LYP/6-31+g(d)] to visualize possible NOE interactions.
Electronic supplementary material The online version of this article (doi:) contains supplementary material, which is available to authorized users. 相似文献
214.
Disinfection of drinking water contaminated with Cryptosporidium parvum oocysts under natural sunlight and using the photocatalyst TiO2 总被引:1,自引:0,他引:1
Méndez-Hermida F Ares-Mazás E McGuigan KG Boyle M Sichel C Fernández-Ibáñez P 《Journal of photochemistry and photobiology. B, Biology》2007,88(2-3):105-111
The results of a batch-process solar disinfection (SODIS) and solar photocatalytic disinfection (SPCDIS) on drinking water contaminated with Cryptosporidium are reported. Cryptosporidium parvum oocyst suspensions were exposed to natural sunlight in Southern Spain and the oocyst viability was evaluated using two vital dyes [4',6-diamidino-2-phenylindole (DAPI) and propidium iodide (PI)]. SODIS exposures (strong sunlight) of 8 and 12h reduced oocyst viability from 98% (+/-1.3%) to 11.7% (+/-0.9%) and 0.3% (+/-0.33%), respectively. SODIS reactors fitted with flexible plastic inserts coated with TiO2 powder (SPCDIS) were found to be more effective than those which were not. After 8 and 16 h of overcast and cloudy solar irradiance conditions, SPCDIS reduced oocyst viability from 98.3% (+/-0.3%) to 37.7% (+/-2.6%) and 11.7% (+/-0.7%), respectively, versus to that achieved using SODIS of 81.3% (+/-1.6%) and 36.0% (+/-1.0%), respectively. These results confirm that solar disinfection of drinking water can be an effective household intervention against Cryptosporidium contamination. 相似文献
215.
Shultz DA Sloop JC Coote TA Beikmohammadi M Kampf J Boyle PD 《Inorganic chemistry》2007,46(1):273-277
A series of functionalized radical anion semiquinone (SQ-Ar) ligands and their MnII- and CuIIhydro-tris(3-cumenyl-5-methylpyrazolyl)borate (TpCum,MeMII) complexes were prepared and characterized. The semiquinone ligands have substituted phenyl rings (Ar = -C6H5NO2, -C6H5OMe, -C6H5-tert-Bu, etc.) attached to the SQ 5-position. Despite the "remoteness" of the phenyl ring substituents, the MII-SQ exchange parameters, J, were found to vary nearly 3-fold. Attempts to quantify the substituent effects on J are complicated by the fact that not all complexes could be structurally characterized. As such, substituent effects and phenyl-ring torsion angles could conspire to produce the observed variation in J values. Although there is no clear trend in the J values as a function of SQ substituent for the MnII complexes, for the CuII complexes, electron-withdrawing substituents on the phenyl ring have greater ferromagnetic J values than the CuII complexes of SQ ligands with electron-donating substituents. This trend suggests a FM contribution from MLCT excited states in the copper complexes. 相似文献
216.
John B. Bremner Prof. Paul A. Keller Assoc. Prof. Stephen G. Pyne Prof. Timothy P. Boyle Dr. Zinka Brkic Dr. Dorothy M. David Adel Garas Dr. Jody Morgan Dr. Mark Robertson Dr. Kittiya Somphol Dr. Michael H. Miller Dr. Adam S. Howe Dr. Paul Ambrose Dr. Sujata Bhavnani Dr. Thomas R. Fritsche Dr. Douglas J. Biedenbach Dr. Ronald N. Jones Dr. Robert W. Buckheit Jr. Dr. Karen M. Watson Dean Baylis Jonathan A. Coates Dr. John Deadman Dr. Dharshini Jeevarajah Andrea McCracken Dr. David I. Rhodes Dr. 《Angewandte Chemie (International ed. in English)》2010,49(3):537-540
217.
We study self-homeomorphisms of zero dimensional metrizable compact Hausdorff spaces by means of the ordered first cohomology
group, particularly in the light of the recent work of Giordano Putnam, and Skau on minimal homeomorphisms. We show that flow
equivalence of systems is analogous to Morita equivalence between algebras, and this is reflected in the ordered cohomology
group. We show that the ordered cohomology group is a complete invariant for flow equivalence between irreducible shifts of
finite type; it follows that orbit equivalence implies flow equivalence for this class of systems. The cohomology group is
the (pre-ordered) Grothendieck group of the C*-algebra crossed product, and we can decide when the pre-ordering is an ordering, in terms of dynamical properties. 相似文献
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