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111.
Bioadhesives and glues are widely used as an adjunct to conventional methods employed in healing the post‐surgical injuries and restoration of normal tissue functions. Protein‐based bioadhesives have been used for a long time, and they are a more biocompatible alternative compared with synthetic adhesives. They offer advantages such as ease of application, reduction in surgery time, improved quality and strength of the seal, and effective sealing. Also, bioadhesives are being exploited in different fields like controlled and site‐specific drug delivery systems, and in tissue engineering and regeneration. There are various marketed protein‐based glues that are available in different forms. Thus, all in all, it is a patient compliant system, thereby increasing its recent popularity. This article provides insight into different types and sources of protein‐based bioadhesives, their history of use, mechanism of adhesion. and various products that have been approved by the regulatory authorities for clinical use. It also includes information regarding the products in clinical trials and potential applications. 相似文献
112.
dris Da Bülent Saka Dursun Irk 《Journal of Computational and Applied Mathematics》2006,190(1-2):532-547
The regularized long wave equation (RLW) is solved numerically by using the quintic B-spline Galerkin finite element method. The same method is applied to the time-split RLW equation. Comparison is made with both analytical solutions and some previous results. Propagation of solitary waves, interaction of two solitons are studied. 相似文献
113.
We report ultrashort, high-energy pulse generation from a side-pumped Yb-doped double-clad fiber laser. The laser is operating in the stretched-pulse regime. It directly generates 4.8-ps, 5-nJ pulses that are extracavity compressed to 90 fs. 相似文献
114.
The preparation of activated carbon from sesame shells as raw precursor was investigated in the study by sequentially applying microwave and conventional heating methods assisted by zinc chloride activation. The optimizisation of experimental parameters including microwave power, microwave treatment time, conventional activation time, conventional activation temperature and zinc chloride concentration ratio for the microwave and conventional heating method was performed. The characterization of the prepared activated carbon was done by thermogravimetric and differential thermal measurements, infrared spectroscopy, scanning electron microscopy and specific surface area analyses. The maximum surface area of 1254?m2/g for the prepared activated carbon was obtained at a microwave power of 750?W, a microwave treatment time of 20?min, an activation time of 45?min, an activation temperature of 500°C and zinc chloride concentration ratio of 1:1. Methylene blue and iodine adsorption capacities for the prepared activated carbon were 103 and 1199?mg/g, respectively. 相似文献
115.
Halit Kantekin Ece Tuğba Saka Miraç Nedim Mısır Halise Yalazan Gülbınar Sarkı 《Journal of Coordination Chemistry》2018,71(1):164-182
In this paper, we elucidated the synthesis, characterization, and investigation of catalytic activity studies of new metallophthalocyanines 4 and 5 as the catalyst for phenolic compounds oxidation by trying different types of oxygen sources. The structural characterization of the products was made by a combination of elemental analysis, FT-IR, LC-MS/MS (for phthalonitrile derivative 3), MALDI-TOF mass spectral data (for metallophthalocyanines 4–7), UV–vis spectroscopy (for metallophthalocyanines 4–7), 1H NMR and 13C NMR spectroscopies (for compounds 3 and 6). The synthetic routes for the (trans-3,7-dimethyl-2,6-octadien-1-ol) substituted phthalonitrile derivative 3 and corresponding metallophthalocyanines 4–7 are outlined in Scheme 1. The MPc complexes 4–7 were synthesized via cyclotetramerization of compound 3 in the presence of the corresponding anhydrous metal salts (CoCl2 for 4, CuCl2 for 5, Zn(CH3COO)2 for 6 and MnCl2 for 7) in dry n-pentanol as solvent and 1,8-diazabicyclo[5.4.0]undec-7-ene (DBU) as strong base at reflux temperature under nitrogen gas. Phthalocyanines and their metal complexes, in general, display poor solubility in most of the organic solvents, however, the synthesized metallophthalocyanine complexes 4–7 were highly soluble in common organic solvents because of the introduction of the methyl groups on alkyl chains of peripheral arms. The catalytic activity of compounds 4 and 5 was evaluated for the oxidation of phenolic compounds such as 4-nitrophenol, o-chlorophenol, 2,3-dichlorophenol, and p-methoxyphenol. CoPc 4 displayed good catalytic performance with a full oxidation of 4-nitrophenol into the corresponding benzoquinone and hydroquinone with the highest TON and TOF values within 3 h. 相似文献
116.
Behlul Saka Ronald L Rardin Mark P Langer 《The Journal of the Operational Research Society》2014,65(4):557-571
Although intensity modulated radiation therapy plans are optimized as a single overall treatment plan, they are delivered over 30–50 treatment sessions (fractions) and both cumulative and per-fraction dose constraints apply. Recent advances in imaging technology provide more insight on tumour biology that has been traditionally disregarded in planning. The current practice of delivering physical dose distributions across the tumour may potentially be improved by dose distributions guided by the biological responses of the tumour points. The biological optimization models developed and tested in this paper generate treatment plans reacting to the tumour biology prior to the treatment as well as the changing tumour biology throughout the treatment while satisfying both cumulative and fraction-size dose limits. Complete computational testing of the proposed methods would require an array of clinical data sets with tumour biology information. Finding no open source ones in the literature, the authors sought proof of concept by testing on a simulated head-and-neck case adapted from a more standard one in the CERR library by blending it with available tumour biology data from a published study. The results show computed biologically optimized plans improve on tumour control obtained by traditional plans ignoring biology, and that such improvements persist under likely uncertainty in sensitivity values. Furthermore, adaptive plans using biological information improve on non-adaptive methods. 相似文献
117.
Aleksandra Č. Mišan Neda M. Mimica-Dukić Anamarija I. Mandić Marijana B. Sakač Ivan Lj. Milovanović Ivana J. Sedej 《Central European Journal of Chemistry》2011,9(1):133-142
Rapid Resolution HPLC/DAD method, on a 1.8 μm, 4.6×50 mm column, was developed to enable a rapid separation of a mixture of
17 compounds, which consisted of hydroxybenzoic acids, hydroxycinnamic acids, flavones, flavonols, flavanone, flavonol-glycoside
and antraquinone, in a single run, within 22 minutes. The developed method is precise, accurate and sensitive enough for simultaneous
quantitative evaluation of major compounds in crude and hydrolyzed extracts of parsley, buckthorn, mint, caraway and birch.
In order to overcome the inability to quantify all the phenolic compounds present in the samples caused by lack of external
standards, HPLC approaches for the total phenolic content estimation based on sum of all integrated peak areas were made.
These results were compared with the total phenolic content determined by Folin-Cioacalteu method. Although the correlation
between the series of data was not significant (p<0.05), the difference between the results of total phenolic content obtained spectrophotometrically and by HPLC was not high
in the case of parsley, buckthorn and mint extract. Regarding the obtained results, the HPLC approach could serve as an excellent
tool for total phenolic content estimation, without the need for complete identification of the individual compounds.
相似文献
118.
Thermal reactions of guaiacol (2-methoxyphenol) and syringol (2,6-dimethoxyphenol) were compared in a closed ampoule reactor (N2/400-600 °C/40-600 s) to obtain information on the thermal reactivities of lignin aromatic nuclei, guaiacyl and syringyl types. For both compounds, the O-CH3 bond homolysis, which was observed at >400 °C, initiated their decomposition. This homolysis was followed by several temperature-dependent reactions; radical-induced rearrangement to convert the aromatic OCH3 to aromatic CH3 structures and condensation into high molecular weight (MW) products were the next steps (≈400 °C); then, coke formation became extensive (≈450 °C); effective gas formation required higher temperature such as >550-600 °C. The syringol- and guaiacol-characteristic GC/MS-detectable low MW products were explained with the above mentioned reactions. As for the difference between guaiacol and syringol, coke and gas (especially CH4 and CO2) formation was more extensive in syringol. This effective coking can be explained by the influence of the additional OCH3 group in syringol, which doubles the opportunity for coke formation. This, in turn, reduces the yields of GC/MS-detectable low MW products. Demethoxylation to form guaiacol was also observed in syringol, even though the reactivity was not so high. These reactions are discussed at the molecular level. 相似文献
119.
Shiro Saka 《Macromolecular Symposia》2004,208(1):7-28
The molecular arrangement of wood cell wall is described in relation to the physical and mechanical properties of wood. The chemical composition of wood is also summarized to illustrate the heterogeneity in distribution of cell wall constituents to use wood plup fibers judiciously as natural raw materials for cellulose acetate production. 相似文献