Rapidly stopping hemorrhage by enhancing blood clotting at an opened wound using chitosan/polylactic acid/polycaprolactone wound dressing device

Doxycycline and monosodium glutamate (MSG) loaded chitosan (CHI)/polylactic acid (PLA)/polycaprolactone (PCL) blend film was studied as a model device to deliver drug to targeted human organ which in this case was the skin with opened wound. The CHI/PLA/PCL blend film containing 60 % CHI, 28 % PLA, and 12 % PCL exhibited the good properties for making the dressing device. It was observed that doxycycline/MSG loaded CHI/PLA/PCL blend film could rapidly deliver both doxycycline and MSG at the high release percentage approaching 100 % loaded. MSG accelerated blood clotting and fibrin formation; thus, it exhibited the good hemostatic activity. The antibacterial activity of doxycycline loaded CHI/PLA/PCL blend film against Staphylococcus aureus and Escherichia coli as model bacteria was investigated. Doxycycline release played the crucial role in bacterial inhibition as observed from the lowest bacterial cell dry weight observed when compared with the control bacterial culture or the bacterial cultures with the presence of other films studied.     

Novel superabsorbent materials from bacterial cellulose

A novel process for the production of superabsorbent materials (hydrogels) from bacterial cellulose (BC) was developed. Prior to crosslinking with a water‐soluble polyethylene glycol diacrylate (PEGDA), BC was first carboxymethylated and functionalized with glycidyl methacrylate. The degree of crosslinking influenced the swelling properties of the hydrogels. The use of greater amounts of PEGDA enhanced the formation of a thicker macromolecular network containing fewer capillary spaces in the crosslinked gel. The maximum water retention value of the hydrogels containing 2.5–3.5 mmol of carboxyl groups per gram of gel reached 125 g g^?1 in distilled water, and 29 g g^?1 in saline (0.9% NaCl solution). The highly porous hydrogel architecture with a pore size of 350–600 µm created a high specific surface area. This enables rapid mass penetration in superabsorbent applications. The superabsorbent hydrogels reached 80% of their maximum water absorption capacity in 30 min. © 2018 Society of Chemical Industry     

Sodium Cardanol Sulfonate Surfactant from Cashew Nut Shell Liquid

Sodium cardanol sulfonate surfactant was synthesized from cardanol from cashew nut shell liquid. Surfactant properties of cardanol sulfonate were determined and compared with dodecylbenzene sulfonate. Surface tension values were determined to be 32.25 mN/m for cardanol sulfonate at 20% w/v and 28.00 mN/m for dodecylbenzene sulfonate at 15% w/v. Critical micelle concentrations of dodecylbenzene sulfonate and cardanol sulfonate were found to be 0.435 and 0.372 mol/L, respectively. In comparison with dodecylbenzene sulfonate, the relative detergency of cardanol sulfonate was calculated to be 93.7% compared to dodecylbenzene sulfonate. Results suggest that cardanol sulfonate can be used as alternative anionic surfactant.

Seismic retrofit of substandard beam-column joint by planar joint expansion

A seismic retrofit technique for existing reinforced concrete beam-column connections using planar joint expansion is proposed. The method is based on a two-dimensional expansion of beam-column joint using cast in-situ concrete and dowel bars. The method is economical and architecturally acceptable. Three half-scale sub-standard beam-column specimens were tested under quasi-static cyclic loading. One was control specimen and the other two were retrofitted specimens with triangular and square joint expansion. According to test results, the control specimen showed brittle joint shear failure while retrofitted specimens showed beam flexural failure. The strength, stiffness, energy dissipation and ductility of retrofitted specimens were greatly improved. The planar joint expansion is effective to reduce joint shear stress and improve anchorage bond of beam bar within the joint. The plastic hinge formation can be moved away from column face, thus preventing joint shear failure. The triangular and square expansions perform almost equally well. The construction joints formed at the interfaces between specimen and joint expansion do not produce an adverse effect in cyclic behavior.     

Multimode heat transfer in cyclic flow reversal combustion in a porous medium

Experimental and numerical studies of combustion and multimode heat transfer in a porous medium, with and without a cyclic flow reversal of a mixture through a porous medium, were performed. Parametric studies were done in order to understand combustion characteristics such as maximum flame temperature and radiative heat flux using a one‐ dimensional conduction, convection, radiation and premixed flame model. The porous medium was assumed to emit and absorb radiant energy, while scattering is ignored. Non‐local thermodynamic equilibrium between the solid an d gas is taken into account by introducing separate energy equations for the gas and the solid phase. As a prelimina ry study, the combustion regime was described by a one‐step global mechanism with an internal heat source uniformly dist ributed along the reaction zone. The effects of the flame position, cyclic flow reversal, period of the cyclic flow rever sal, the optical thickness and the flow velocity on the burner performance were clarified by a rigorous radiation analysis. Th e model was validated by comparing the theoretical results with the experiments. It was shown that, for maximizing the fl ame temperature and the net radiative heat flux feedback, the flame should be stabilized near the centre of the po rous medium with a cyclic flow reversal, the period of which should be as small as possible. A high optical thickness prod uced a high flame temperature and a high net radiative feedback. Also, a high flow velocity at low period of the cyclic f low reversal of mixture yielded a high value of both the flame temperature and the net radiative feedback. Thermal structure predictions in terms of the gas‐phase and the solid‐phase temperature distributions along the axis of the combustor show good agreement with the experimental ones. Copyright © 1999 John Wiley & Sons, Ltd.     

Cardanol-Based Bis(azo) Dyes as a Gasoline 91 Colorant

Novel bis(azo) dyes were successfully prepared from the coupling of either natural cardanol or its hydrogenated derivative with a series of diazotized aromatic amines and diamines. These new dyes were fully characterized by NMR, infrared and UV–visible spectroscopy and mass spectrometry. The dyes are highly soluble in a variety of common organic solvents and gasoline as a consequence of the cardanol unit. The physical properties of gasoline according to American Society for Testing and Materials standard were unaffected by the presence of the bis(azo) dye derived from 1-(4aminophenylazo)-2-naphthol at a concentration of 6 ppm and the dye showed excellent stability over a 3 month period.     

Incorporation of nonionic emulsifiers inside styrene–methacrylic acid copolymer particles during emulsion copolymerization

Emulsion copolymerizations of styrene and methacrylic acid with polyoxyethylene nonylphenyl ether nonionic emulsifiers having various hydrophilic–lipophilic balance (HLB) values (13.7, Emulgen 911; 15.5, Emulgen 920; 17.2, Emulgen 931) were performed. The incorporation behavior of the nonionic emulsifiers, comprising polydisperse poly(ethylene oxide) (PEO) chain lengths, inside the particles was investigated. At the completion of the polymerization, the incorporated percentage of the lowest HLB emulsifier was 61%, much higher than that of the highest HLB one (10%). In both polymerizations, the amounts of the incorporated emulsifiers increased with conversion, and shorter PEO chain (i.e., lower molecular weight) components were predominantly incorporated over longer PEO chain components.     

Hemagglutinating activity and corresponding putative sequence identity from Curcuma aromatica rhizome

BACKGROUND: Curcuma aromatica is a medicinal plant belonging to the Zingiberaceae family with an incomplete genome sequence. It has been reported that extract from the rhizome of this plant contains haemagglutinating activity. In this study the profile of fractions containing hemagglutinating activity is described. RESULTS: Following extraction with saline buffer, the protein solution was fractionated by ammonium sulfate precipitation. Ion‐exchange chromatography was completed on fast‐flow SP‐Sepharose, as well as gel filtration chromatography on Superdex 75. The active fractions were then separated by one‐dimensional sodium dodecyl sulfate–polyacrylamide gel electrophoresis and labeled proteins were digested with trypsin. The digest bands were analyzed by reversed‐phase liquid chromatography—tandem mass spectrometry. Inferred peptide sequences were used in Mascot searching and mass spectrometry‐driven BLAST (MS‐BLAST) homology searches allowed the recognition of related proteins in other species of Viridiplantae. Six putative proteins from nine bands showed similarity with lectin sequences. CONCLUSION: This study reports the identification of six lectins from the Curcuma aromatica rhizome achieved by mass spectrometry using MS‐BLAST algorithms to search for homology between de novo determined peptide sequences and protein sequences available in sequence databases. Copyright © 2008 Society of Chemical Industry     

Antifungal and antibacterial activities of lectin from the seeds of Archidendron jiringa Nielsen

A Archidendron jiringa Nielsen lectin was purified by aqueous extraction, 90% ammonium sulphate precipitation and concanavalinA-Sepharose 4B affinity chromatography. Its specific activity was of 88.3 × 10² hemagglutination unit/mg protein for a yield of 51.6% total protein. The molecular weight is of 35.7 kDa. It has hemagglutinating activity against human blood group, rabbit, mouse, rat, guinea pig, geese and sheep erythrocytes. The hemagglutination activity of lectin was relatively insensitive to acidic pH above 2, had an optimal activity at pH 8, and stable below 45 °C for 30 min. The activity was stimulated by Ca²⁺, Mg²⁺ and Mn²⁺. The internal sequence indicated similarity with legume lectin family. Moreover, even at low concentrations antifungal activity was observed against Exserohilum turcicum, Fusarium oxysporum and Colletotrichum cassiicola. The minimal inhibitory concentrations were 0.227, 0.0567 and 0.0567 mg/ml for Bacillus subtilis, Staphylococcus aureus, and Candida albicans, respectively.