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651.
The iodometric determination of peroxides in certain edible oils by the use of standard L-ascorbic acid solution is reported. Calculation of Lea number by the proposed method and the previously recognised sodium thiosulphate method is also given.  相似文献   
652.
Multimedia Tools and Applications - Today, images editing software has greatly evolved, thanks to them that the semantic manipulation of images has become easier. On the other hand, the...  相似文献   
653.
The widely used rat uterotrophic assay to assess known and potential estrogenic compounds only considers uterine weight gain as endpoint measurement. To complement this method with an advanced technology that reveals molecular targets, we analyzed changes in protein expression using label-free quantitative proteomics by nanoflow liquid chromatography coupled with high-resolution mass spectrometry and tandem mass spectrometry from uterine protein extracts of ovariectomized rats after daily 17β-estradiol exposure for five days in comparison with those of vehicle-treated control animals. Our discovery-driven study revealed 165 uterine proteins significantly regulated by estrogen treatment and mapped by pathway analyses. Estrogen-regulated proteins represented cell death, survival and development, cellular growth and proliferation, and protein synthesis as top molecular and cellular functions, and a network found with the presence of nuclear estrogen receptor(s) as a prominent molecular node confirmed the relevance of our findings to hormone-associated events. An exploratory application of targeted proteomics to bisphenol A as a well-known example of an estrogenic endocrine disruptor is also presented. Overall, the results of this study have demonstrated the power of combining untargeted and targeted quantitative proteomic strategies to identify and verify candidate molecular markers for the evaluation of endocrine-disrupting chemicals to complement a conventional bioassay.  相似文献   
654.
Multimedia Tools and Applications - Diabetic retinopathy is the main cause of the blindness worldwide. However, the diabetic retinopathy is hard to be detected in the initial stages, and the...  相似文献   
655.
Coagulation/flocculation process, Fenton oxidation and combinations between them were studied, aiming to provide an efficient method for the treatment of partially stabilized leachates. Leachates were collected from a municipal landfill site, samples containing around 3800 mg/L COD, BOD5/COD ratio about 0.11 and pH around 8. The sequence of stages implemented was: (a) coagulation/flocculation; (b) Fenton oxidation; (c) coagulation/flocculation followed by Fenton oxidation which resulted in a best COD removal (63.62%) and (d) Fenton oxidation followed by coagulation/flocculation.  相似文献   
656.
ABSTRACT

The acid fraction of crude oils and related source rocks of different stratigraphic units from the Gulf of Suez and Western Desert, Egypt were analyzed by GC and GC/MS. Normal alkanoic acids (n-C9?n-C30) were the dominant series (with the predominance of even-carbon numbers maximizing at n-C16, n-C18 or n-C22while iso- and anteiso- branched acids were minor constituents. All samples showed a preference of short chain acids (n-C10?n-C19 with respect to long chain acids (n-C20+) typical of marine oils and source rocks. The n-alkanoic acids distribution suggests a predominant algal and/or bacterial contribution. The presence of high relative abundance of mono and di-unsaturated carboxylic acids in a number of samples point to recent microbial activity. Distributions of n-alkanoic acids in the range (C12?C22) show striking similarities with the n-alkane distributions, indicating that both series may, at least in part, be diagenetically related by decarboxylation of the acids. Dehydroabietic acid has been identified in only one sample from Balaim Marine source rock. This resin-derived compound has probably been transported as pollen to the marine environment.  相似文献   
657.
A series of new 2-aminobenzamide derivatives (1–10) has been synthesized in good to excellent yields by adopting both conventional and/or a time-efficient microwave assisted methodologies starting from isatoic anhydride (ISA) and characterized on the basis of their physical, spectral and microanalytical data. Selected compounds of this series were then tested against various bacterial (Bacillus subtilis (RCMB 000107) and Staphylococcus aureus (RCMB 000106). Pseudomonas aeruginosa (RCMB 000102) and Escherichia coli (RCMB 000103) and fungal strains (Saccharomyces cerevisiae (RCMB 006002), Aspergillus fumigatus (RCMB 002003) and Candida albicans (RCMB 005002) to explore their potential as antimicrobial agents. Compound 5 was found to be the most active compound among those tested, which showed excellent antifungal activity against Aspergillus fumigatus (RCMB 002003) more potent than standard Clotrimazole, and moderate to good antibacterial and antifungal activity against most of the other strains of bacteria and fungi. Furthermore, potential pharmacophore sites were identified and their activity was related with the structures in the solution.  相似文献   
658.
Electroconvulsive therapy (ECT) has been successfully used in the treatment of depression, particularly when the illness is refractory to pharmacological therapy. A recent study has shown that ECT is also effective in reducing both depressive and posttraumatic stress disorder (PTSD) symptoms in patients with major depression (MDD) and co-occurring PTSD. This raises the possibility that ECT might be effective in the treatment of PTSD, a disease whose prevalence has increased substantially in recent years. A characteristic symptom of PTSD is an exaggerated reactivity to startling sounds (acoustic startle response; ASR). In the present study, we investigated the effects of electroconvulsive shocks (ECS) on the ASR, in a rat model of traumatic stress. The animals were subjected to a restraint/tailshock paradigm and then administered ECS. ASR measurements were obtained at several time points following ECS administration. Although ECS had no effect in control rats, it significantly exacerbated the already potentiated ASR in the stressed group. While ECT may prove to be an effective treatment for certain symptoms of co-occurring MDD/PTSD or PTSD alone, it may exacerbate heightened arousal associated with PTSD. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
659.
Existing works on Wiener system identification have essentially been focused on the case where the output nonlinearity is memoryless. When memory nonlinearities have been considered, the focus has been restricted to backlash like nonlinearities. In this paper, we are considering Wiener systems where the output nonlinearity is a general hysteresis operator captured by the well‐known Bouc–Wen model. The Wiener system identification problem is addressed by making use of a steady‐state property, obtained in periodic regime, referred to as ‘hysteretic loop assumption’. The complexity of this problem comes from the system nonlinearity as well as its unknown parameters that enter in a non‐affine way in the model. It is shown that the linear part of the system is accurately identified using a frequency method. Then, the nonlinear hysteretic subsystem is identified, on the basis of a parameterized representation, using a prediction‐error approach. Copyright © 2016 John Wiley & Sons, Ltd.  相似文献   
660.
This paper reports details about the synthesis of a series of novel functionalized symmetrical bis-heterocyclic compounds containing a thieno[2,3-b]thiophene motif. Bis-thiazole derivatives 2, 3a-c and thiazolo[3,2-a]pyridine derivatives 4a-c are achieved. The hitherto unknown dihydrothiophene derivatives 6a-dvia bis-pyridimium salt 5 are obtained. Additionally, the novel hydrazonothieno[2,3-b]thiophene derivatives 10a-c are obtained via bis-tosylacetylthieno[2,3-b]thiophene derivative 9. All compounds are characterized by (1)H-, (13)C-NMR, GCMS, IR, and UV-vis spectrometry. These compounds represent a new class of sulfur and nitrogen containing heterocycles that should also be of interest as new materials.  相似文献   
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