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991.
Two heterobimetallic coordination complexes [Co(acac)Cu2(bdmap)2Cl3]·C7H8 (1) and [Co(acac)Cu2(bdmap)2Cl3]·3CH2Cl2 (2) [bdmap = 1,3-Bis(dimethylamino)-2-propanol and acac = 2,4-pentanedionate], have been synthesized by simple chemical technique and characterized by their melting points, elemental composition, FT-IR spectroscopy, mass spectrometry and single crystal X-ray analysis. Thermograms of both the precursors indicated their facile decomposition at relatively low temperature of 454 °C to give stable residual mixture of Cu and CoO. Both the precursors are utilized for the deposition of Cu-CoO thin films by aerosol-assisted chemical vapor deposition (AACVD) equipment at 450 °C on glass substrates that were subsequently characterized for their morphology and composition of the ceramic material. The scanning electron microscopy of copper-cobalt oxide films grown from both the precursors describe highly compact and smooth morphology with homogenously dispersed spherical particles with excellent adhesion properties to the substrates. The EDX analysis shows homogeneous distribution of metallic elements with Cu:Co ratio close to 2:1. Powder X-ray diffraction analysis of the films shows that they are composed of Cu/CoO composite and are crystalline in nature having particle size in the range of 0.3-0.8 μm. 相似文献
992.
Michael K. Dame Narasimharao Bhagavathula Cohra Mankey Marissa DaSilva Tejaswi Paruchuri Muhammad Nadeem Aslam James Varani 《In vitro cellular & developmental biology. Animal》2010,46(2):114-122
Normal and neoplastic human colon tissue obtained at surgery was used to establish conditions for organ culture. Optimal conditions
included an atmosphere of 5% CO2 and 95% O2; tissue partially submerged with mucosa at the gas interface; and serum-free medium with 1.5 mM Ca2+ and a number of growth supplements. Histological, histochemical, and immunohistochemical features that distinguish normal
and neoplastic tissue were preserved over a 2-d period. With normal tissue, this included the presence of elongated crypts
with small, densely packed cells at the crypt base and mucin-containing goblet cells in the upper portion. Ki67 staining,
for proliferating cells, was confined to the lower third of the crypt, while expression of extracellular calcium-sensing receptor
was seen in the upper third and surface epithelium. E-cadherin and β-catenin were expressed throughout the epithelium and
confined to the cell surface. In tumor tissue, the same disorganized, abnormal glandular structures seen at time zero were
present after 2 d. The majority of cells in these structures were mucin-poor, but occasional goblet cells were seen and mucin
staining was present. Ki67 staining was seen throughout the abnormal epithelium and calcium-sensing receptor expression was
weak and variable. E-cadherin was seen at the cell surface (similar to normal tissue), but in some places, there was diffuse
cytoplasmic staining. Finally, intense cytoplasmic and nuclear β-catenin staining was observed in cultured neoplastic tissue. 相似文献
993.
Muhammad Naeem Anjum William Parker Russell Ruo Muhammad Afzal 《Physica medica : PM : an international journal devoted to the applications of physics to medicine and biology : official journal of the Italian Association of Biomedical Physics (AIFB)》2010,26(1):38-43
The aim of this study was to use different gamma histogram criteria for the comparison of planned dose with irradiated dose distribution and find that what percent of pixels passing a certain criteria imitate a good quality plan. The dose was calculated for 156 patients by inverse planning optimization using the Corvus treatment planning system. Gafchromic films in combination with 2571 0.6 cm3 Farmer type ionization chamber and Farmer 2570/1 electrometer from NE Technology were used to measure the delivered dose in solid water phantom. All the measurements were performed on Varian CL21EX linear accelerator (Varian Medical Systems, Palo Alto, CA) fitted with a Millennium 120 leaf collimator. In this study the mean value of the percent of passing pixels within the region of interest under the criterion of 3% DD and 3 mm DTA is 90.2 ± 7.1% for head and neck cases and 92.2 ± 5.8% for non-head and neck cases. If we choose the criteria of 3% DD and 3 mm DTA then 96.3% head and neck plans have the percent of passing pixels ≥ 75% and 95.1% non-head and neck plans have the percent of passing pixels ≥ 80%. It is evident from the results of this study that the criterion of 5% DD and 3 mm DTA with the percent of passing pixels ≥ 90 for non-head and neck cases while the percent of passing pixels ≥ 85 for head and neck cases endorse that a plan is good. The results of this study may be useful for other institutions which use verification software and EBT films for patient specific IMRT QA. 相似文献
994.
A significant proportion of all incidents of nosocomial infections in acute-care hospitals is due to contaminated catheters. Alternative strategies e.g. antibiotics as well as surface modifications have been devised in an attempt to reduce the incidence of catheter-associated urinary tract infections (CAUTI), but most have proven unsuccessful. Therefore, the race to identify such substances which can combat pathogenic bacteria is ongoing in order to improve the quality of health care. Novel technologies such as the potential use of antiseptic or antimicrobial coatings on catheters hold promise for reducing these infections in the fight against antimicrobial resistance. In this study, the bactericidal activity of newly synthesized tungsten-nanoparticles was tested on clinical multiple drug resistant Escherichia coli isolates from UTI patients with indwelling catheters and Staphylococcus aureus reference strain. The results suggest that the particles tested in this study certainly mediate the inhibition of bacterial growth. We believe that the fabrication of W-NPs on catheters could possibly prevent them from being contaminated by pathogens and hence provide continuous protection of the site. This study is the first of its type testing the antibacterial effects of W-NPs on clinical bacterial isolate from catheterized human UTI case. 相似文献
995.
996.
Farhan Ahmad Pasha Muhammad Muddassar Anil Kumar Srivastava Seung Joo Cho 《Journal of molecular modeling》2010,16(2):263-277
Members of the epidermal growth factor receptor (EGFR) family of proteins are frequently overactive in solid tumors. A relatively
new therapeutic approach to inhibit the kinase activity is the use of ATP-competitive small molecules. In silico techniques
were employed to identify the key interactions between inhibitors and their protein receptors. A series of EGFR inhibitory
anilinoquinolines was studied within the framework of hologram quantitative structure activity relationship (HQSAR), density
functional theory (DFT)-based QSAR, and three-dimensional (3D) QSAR (CoMFA/CoMSIA). The HQSAR analysis implied that substitutions
at certain sites on the inhibitors play an important role in EGFR inhibition. DFT-based QSAR results suggested that steric
and electronic interactions contributed significantly to the activity. Ligand-based 3D-QSAR and receptor-guided 3D-QSAR analyses
such as CoMFA and CoMSIA techniques were carried out, and the results corroborated the previous two approaches. The 3D QSAR
models indicated that steric and hydrophobic interactions are dominant, and that substitution patterns are an important factor
in determining activity. Molecular docking was helpful in identifying a bioactive conformer as well as a plausible binding
mode. The docked geometry-based CoMFA model with steric and electrostatic fields effect gave q
2 = 0.66, r
2 = = 0.94 with r
2
predictive = 0.72. Similarly, CoMSIA with hydrophobic field gave q
2 = 0.59, r
2 = 0.85 with r
2
predictive = 0.63. Bulky groups around site 3 of ring “C”, and hydrophilic and bulky groups at position 6 of ring “A” are desirable,
with a hydrophobic and electron-donating group at site 7 of ring “A” being helpful. Accordingly, potential EGFR inhibitors
may be designed by modification of known inhibitors. 相似文献
997.
This experiment was designed to compare powdered egg yolk with fresh egg yolk in an extender for cryopreservation of Zebu bull semen. Sperm motility, plasma membrane integrity and viability were assessed at different stages of cryopreservation (post-dilution, pre-freezing and post-thawing). Sperm plasma membrane integrity remained similar at all the stages of cryopreservation. Sperm motility and viability were significantly higher after thawing in the extender containing powdered egg yolk. In conclusion, powdered egg yolk may be used in an extender for the cryopreservation of Zebu bull spermatozoa. 相似文献
998.
Azhar Muhammad Quoc Viet Nguyen Hoon Cheol Park Do Y.Hwang Doyoung Byun Nam Seo Goo 《仿生工程学报(英文版)》2010,7(2):134-141
<正> In an attempt to realize a flapping wing micro-air vehicle with morphing wings, we report on improvements to our previousfoldable artificial hind wing.Multiple hinges, which were implemented to mimic the bending zone of a beetle hind wing, weremade of small composite hinge plates and tiny aluminum rivets.The buck-tails of rivets were flared after the hinge plates wereassembled with the rivets so that the folding/unfolding motions could be completed in less time, and the straight shape of theartificial hind wing could be maintained after fabrication.Folding and unfolding actions were triggered by electrically-activatedShape Memory Alloy (SMA) wires.For wing folding, the actuation characteristics of the SMA wire actuator were modifiedthrough heat treatment.Through a series of flapping tests, we confirmed that the artificial wings did not fold back and arbitrarilyfluctuate during the flapping motion. 相似文献
999.
Syed Muhammad Zaka Xin-Nian Zeng Paul Holford George Andrew Charles Beattie 《Insect Science》2010,17(1):39-45
Abstract The Asiatic citrus psyllid ( Diaphorina citri Kuwayama [Hemiptera: Sternorrhyncha: Psyllidae]) is a vector of huanglongbing (citrus greening), a devastating disease of citrus caused by phloem-limited bacteria. Growing guava ( Psidium guajava ) as an intercrop appears to be a successful means of reducing psyllid numbers within citrus orchards; however, the mechanism by which such a reduction is achieved is unknown. To determine the repellent effect of guava leaf and factors attributed to this activity, responses of adult psyllids to guava leaf and its odor were evaluated in cage tests and Y-tube olfactometer test. The results showed that guava leaf possessed a repellent effect against the adult citrus psyllids. Fewer psyllids were found on citrus leaves in the presence of guava foliage than in its absence. Young and old guava leaf showed equal repellent activity. By covering the guava shoots with net cloth, it was revealed that the repellent effect of guava leaf against adult psyllids on citrus was attributed to the volatile compounds, rather than physical factors. The olfactometer response of adult psyllids to guava leaf odor was dosage-dependent. Between guava odor and control, only 35.00%, 25.00% and 16.25% of the psyllids moved toward guava odor when presented with 5.0, 10.0 and 15.0 g of guava shoots, respectively. The olfactometer experiments also showed that both male and female psyllids responded similarly to the guava leaf odor. 相似文献
1000.
Wheat production in Pakistan is seriously constrained due to rust diseases and stripe rust (yellow) caused by Puccinia striiformis f. sp. tritici, which could limit yields. Thus development and cultivation of genetically diverse and resistant varieties is the most sustainable
solution to overcome these diseases. The first objective of the present study was to evaluate 100 Pakistan wheat cultivars
that have been grown over the past 60 years. These cultivars were inoculated at the seedling stage with two virulent stripe
rust isolates from the United States and two from Pakistan. None of the wheat cultivars were resistant to all tested stripe
rust isolates, and 16% of cultivars were susceptible to the four isolates at the seedling stage. The data indicated that none
of the Pakistan wheat cultivars contained either Yr5 or Yr15 genes that were considered to be effective against most P. striiformis f. sp. tritici isolates from around the world. Several Pakistan wheat cultivars may have gene Yr10, which is effective against isolate PST-127 but ineffective against PST-116. It is also possible that these cultivars may
have other previously unidentified genes or gene combinations. The second objective was to evaluate the 100 Pakistan wheat
cultivars for stripe rust resistance during natural epidemics in Pakistan and Washington State, USA. It was found that a higher
frequency of resistance was present under field conditions compared with greenhouse conditions. Thirty genotypes (30% of germplasms)
were found to have a potentially high temperature adult plant (HTAP) resistance. The third objective was to determine the
genetic diversity in Pakistan wheat germplasms using molecular markers. This study was based on DNA fingerprinting using resistance
gene analog polymorphism (RGAP) marker analysis. The highest polymorphism detected with RGAP primer pairs was 40%, 50% and
57% with a mean polymorphism of 36%. A total of 22 RGAP markers were obtained in this study. RGAP, simple sequence repeat
(SSR) and sequence tagged site (STS) markers were used to determine the presence and absence of some important stripe rust
resistance genes, such as Yr5, Yr8, Yr9, Yr15 and Yr18. Of the 60 cultivars analyzed, 17% of cultivars showed a RGAP marker band for Yr9 and 12% of cultivars exhibited the Yr18 marker band. No marker band was detected for Yr5, Yr8 and Yr15, indicating a likely absence of these genes in the tested Pakistan wheat cultivars. Cluster analysis based on molecular and
stripe rust reaction data is useful in identifying considerable genetic diversity among Pakistan wheat cultivars. The resistant
germplasms identified with 22 RGAP markers and from the resistance evaluations should be useful in developing new wheat cultivars
with stripe rust resistance. 相似文献