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591.
In a projective plane $PG(2,\mathbb K )$ over an algebraically closed field $\mathbb K $ of characteristic $p\ge 0$ , let $\Omega $ be a pointset of size $n$ with $5\le n \le 9$ . The coset intersection problem relative to $\Omega $ is to determine the family $\mathbf F$ of irreducible cubics in $PG(2,\mathbb K )$ for which $\Omega $ is a common coset of a subgroup of the additive group $(\mathcal F ,+)$ for every $\mathcal F \in \mathbf F$ . In this paper, a complete solution of this problem is given. 相似文献
592.
Giuseppina Orlandini Sonia Bacca Nir Barnea Gaute Hagen Mirko Miorelli Thomas Papenbrock 《Few-Body Systems》2014,55(8-10):907-911
Here we summarize how the LIT and CC methods can be coupled, in order to allow for ab initio calculations of reactions in medium mass nuclei. Results on 16O are reviewed and preliminary calculations on 40Ca are presented. 相似文献
593.
An advanced and powerful chemometric approach is proposed for the analysis of incomplete multiset data obtained by fusion of hyphenated liquid chromatographic DAD/MS data with UV spectrophotometric data from acid–base titration and kinetic degradation experiments. Column- and row-wise augmented data blocks were combined and simultaneously processed by means of a new version of the multivariate curve resolution-alternating least squares (MCR-ALS) technique, including the simultaneous analysis of incomplete multiset data from different instrumental techniques. The proposed procedure was applied to the detailed study of the kinetic photodegradation process of the amiloride (AML) drug. All chemical species involved in the degradation and equilibrium reactions were resolved and the pH dependent kinetic pathway described. 相似文献
594.
Santagati NA Salerno L Attaguile G Savoca F Ronsisvalle G 《Journal of chromatographic science》2008,46(2):150-156
A simple high-performance liquid chromatography method using a diode array detector (DAD) is developed for the simultaneous analysis of five major catechins: (+)-catechin (C), (-)-epicatechin (EC), (-)-gallocatechin (GCT), (-)-epigallocatechin (EGC), (-)-epigallocatechin gallate (EGCG), and the phenolic plant metabolites gallic acid (GA) and rutin (RT) in lyophilized extracts of Cistus species. The optimal analytical conditions are investigated to obtain the best resolution and the highest UV sensitivity for the quantitative detection of catechins. The optimized conditions (acetonitrile-phosphate buffer 50mM, pH 2.5, gradient elution system on a C(18) reversed-phase column with a flow rate of 1 mL/min and UV absorbance at 210 nm) allowed a specific and repeatable separation of the studied analytes to be achieved. All compounds are successfully separated within 32 min. Calibration curves are linear in the 2-50 microg/mL range for GCT, C, and EGCG and in the 5-50 microg/mL range for GA, EGC, EC, and RT. The limit of detection values ranged from 0.24 to 0.74 microg/mL. The limit of quantitation limit values ranged from 0.77 to 1.94 microg/mL. The validated method is applied to the determination of the specific phytochemical markers GA, GCT, C, and RT in Cistus incanus and Cistus monspeliensis lyophilised extracts. The recovery values ranged between 78.7% and 98.2%. The described HPLC method appears suitable for the differentiation and determination of the most common catechins together with the glycoside rutin and the phenolic compound gallic acid and can be considered an effective and alternative procedure for the analyses of this important class of natural compounds. 相似文献
595.
Yuhao Yang Seyedesahar Miraghaee Renee Pace Dr. Teruo Umemoto Prof. Gerald B. Hammond 《Angewandte Chemie (International ed. in English)》2023,62(32):e202306095
A novel, air and thermally stable, yet highly reactive trifluoromethylthiolating reagent, CF3SO2SCF3 ( 1 ), was prepared easily in one step from commercially inexpensive CF3SO2Na and Tf2O. 1 is a highly versatile and atom-efficient reagent that can generate one equivalent of CF3S + , two equivalents of CF3S−, or a combination of CF3S⋅/CF3⋅ species. Many high-yielding CF3S reactions of C, O, S, and N-nucleophiles were achieved, including the simple-step preparations of many reported CF3S reagents. 1 delivered a hitherto hard-to-synthesize ArOSCF3 that was followed by a novel CF3SII-rearrangement. Through Cu or TDAE/Ph3P combinations, 1 generated two equivalents of CF3S anion species, and the photo-catalyzed reactions of alkenes with 1 provided CF3/CF3S-containing products in high atom-efficiency. 相似文献
596.
Giuseppina Biscari Yanmiao Fan Faridah Namata Calogero Fiorica Michael Malkoch Fabio Salvatore Palumbo Giovanna Pitarresi 《Macromolecular bioscience》2023,23(12):2300224
Treating wound infections is a difficult task ever since pathogenic bacteria started to develop resistance to common antibiotics. The present study develops hybrid hydrogels based on the formation of a polyelectrolyte complex between the anionic charges of dopamine-functionalized Gellan Gum (GG-DA) and the cationic moieties of the TMP-G2-alanine dendrimer. The hydrogels thus obtained can be doubly crosslinked with CaCl2, obtaining solid hydrogels. Or, by oxidizing dopamine to GG-DA, possibly causing further interactions such as Schiff Base and Michael addition to take place, hydrogels called injectables can be obtained. The latter have shear-thinning and self-healing properties (efficiency up to 100%). Human dermal fibroblasts (HDF), human epidermal keratinocytes (HaCaT), and mouse monocyte cells (RAW 264.7), after incubation with hydrogels, in most cases show cell viability up to 100%. Hydrogels exhibit adhesive behavior on various substrates, including porcine skin. At the same time, the dendrimer serves to crosslink the hydrogels and endows them with excellent broad-spectrum microbial eradication activity within four hours, evaluated using Staphylococcus aureus 2569 and Escherichia coli 178. Using the same GG-DA/TMP-G2-alanine ratios hybrid hydrogels with tunable properties and potential for wound dressing applications can be produced. 相似文献
597.
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600.
Martins-de-Souza D Gattaz WF Schmitt A Rewerts C Maccarrone G Dias-Neto E Turck CW 《Journal of separation science》2008,31(16-17):3122-3126
The prefrontal cortex executes important functions such as differentiation of conflicting thoughts, correct social behavior and personality expression, and is directly implicated in different neurodegenerative diseases. We performed a shotgun proteome analysis that included IEF fractionation, RP-LC, and MALDI-TOF/TOF mass spectrometric analysis of tryptic digests from a pool of seven human dorsolateral prefrontal cortex protein extracts. In this report, we present a catalog of 387 proteins expressed in these samples, identified by two or more peptides and high confidence search scores. These proteins are involved in different biological processes such as cell growth and/or maintenance, metabolism/energy pathways, cell communication/signal transduction, protein metabolism, transport, regulation of nucleobase, nucleoside, nucleotide and nucleic acid metabolism, and immune response. This analysis contributes to the knowledge of the human brain proteome by adding sample diversity and protein expression data from an alternative technical approach. It will also aid comparative studies of different brain areas and medical conditions, with future applications in basic and clinical research. 相似文献