Variable-Dependent Partial Dimension Reduction

Sufficient dimension reduction reduces the dimension of a regression model without loss of information by replacing the original predictor with its lower-dimensional linear combinations. Partial (sufficient) dimension reduction arises when the predictors naturally fall into two sets X and W, and pursues a partial dimension reduction of X. Though partial dimension reduction is a very general problem, only very few research results are available when W is continuous. To the best of our knowledge, none can deal with the situation where the reduced lower-dimensional subspace of X varies with W. To address such issue, we in this paper propose a novel variable-dependent partial dimension reduction framework and adapt classical sufficient dimension reduction methods into this general paradigm. The asymptotic consistency of our method is investigated. Extensive numerical studies and real data analysis show that our variable-dependent partial dimension reduction method has superior performance compared to the existing methods

Variable-Dependent Partial Dimension Reduction

Sufficient dimension reduction reduces the dimension of a regression model without loss of information by replacing the original predictor with its lower-dimensional linear combinations. Partial (sufficient) dimension reduction arises when the predictors naturally fall into two sets X and W, and pursues a partial dimension reduction of X. Though partial dimension reduction is a very general problem, only very few research results are available when W is continuous. To the best of our knowledge, none can deal with the situation where the reduced lower-dimensional subspace of X varies with W. To address such issue, we in this paper propose a novel variable-dependent partial dimension reduction framework and adapt classical sufficient dimension reduction methods into this general paradigm. The asymptotic consistency of our method is investigated. Extensive numerical studies and real data analysis show that our variable-dependent partial dimension reduction method has superior performance compared to the existing methods

Enzymatic treatments to improve mechanical properties and surface hydrophobicity of jute fiber membranes

Fiber membranes prepared from jute fragments can be valuable, low cost, and renewable. They have broad application prospects in packing bags, geotextiles, filters, and composite reinforcements. Traditionally, chemical adhesives have been used to improve the properties of jute fiber membranes. A series of new laccase, laccase/mediator systems, and multi-enzyme synergisms were attempted. After the laccase treatment of jute fragments, the mechanical properties and surface hydrophobicity of the produced fiber membranes increased because of the cross-coupling of lignins with ether bonds mediated by laccase. The optimum conditions were a buffer pH of 4.5 and an incubation temperature of 60 °C with 0.92 U/mL laccase for 3 h. Laccase/guaiacol and laccase/alkali lignin treatments resulted in remarkable increases in the mechanical properties; in contrast, the laccase/2,2-azino-bis-(3-ethylthiazoline-6-sulfonate) (ABTS) and laccase/2,6-dimethoxyphenol treatments led to a decrease. The laccase/ guaiacol system was favorable to the surface hydrophobicity of jute fiber membranes. However, the laccase/alkali lignin system had the opposite effect. Xylanase/laccase and cellulase/laccase combined treatments were able to enhance both the mechanical properties and the surface hydrophobicity of jute fiber membranes. Among these, cellulase/laccase treatment performed better; compared to mechanical properties, the surface hydrophobicity of the jute fiber membranes showed only a slight increase after the enzymatic multi-step processes.Financially supported by the National Natural Science Foundation of China (51173071, 21274055), Program for New Century Excellent Talents in University (NCET-12-0883), Program for Changjiang Scholars, Innovative Research Team in University (IRT _15R26), and Fundamental Research Funds for the Central Universities (JUSRP51312B, JUSRP51505

Enzymatic coating of jute fabrics for enhancing anti-ultraviolent properties via in-situ polymerization of polyhydric phenols

To enhance the anti-ultraviolent properties of technical jute fabrics, the enzymatic surface coating with the in-situ produced phenolic polymers of polyhydric phenols was investigated in this study. Firstly, the laccase-mediated polymerization of the five polyhydric phenols (catechol, resorcinol, hydroquinone, pyrogallol and phloroglucinol) was analyzed by FT-IR. Catechol and pyrogallol were polymerized together by laccase with ether bonds linked. On the contrary, the units of resorcinol, hydroquinone and phloroglucinol in their enzymatically formed polymers concatenated to each other by C-C bonds. Then, the coated jute fabrics were characterized in terms of X-ray photoelectron spectroscopy and scanning electron microscopy. The increasing of the C/O ratio on the jute fabric surface after the coating treatments supported the achievement of the enzymatic coating on jute fabrics via the in-situ polymerization of phenolic compounds and the grafting reaction of polyphenols with lignins on the surface. The sequence of the coating extent by using various polyhydric phenols was proved to be catechol, pyrogallol, resorcinol, phloroglucinol and hydroquinone in order from rich to poor according to the O-C-O component of cellulose in the C1s spectra of jute fabrics and the scanning electron microscopy photographs of jute surfaces. Lastly, the ultraviolent protection factor and the ultraviolent resistance of the coated jute fabrics were measured. The ultraviolent protective performance of jute fabrics after the coating treatments depended both on the coating amount and the chemical structure of the coated polymers. Among the tested polyhydric phenols, the polymerization of catechol obtained the best coating for ultraviolent protection. Different polyhydric phenols employed for the enzymatic coating showed different trends in ultraviolent protection factor of jute fabrics with the increasing of incubation time. The jute fabrics coated with in-situ-generated polycatechols or polyresorcinols had excellent ultraviolent resistances.The author(s) disclosed receipt of the following financial support for the research, authorship, and/or publication of this article: This work was Enancially supported by National Natural Science Foundation of China (51173071), Program for New Century Excellent Talents in University (NCET-12-0883), Program for Changjiang Scholars and Innovative Research Team in University (IRT1135), Fundamental Research Funds for the Central Universities (JUSRP51312B), the Graduate Student Innovation Plan of Jiangsu Province of China (CXZZ13_0752) and the Doctor Candidate Foundation of Jiangnan University of China (JUDCF13023)

Small Interference RNA Targeting TLR4 Gene Effectively Attenuates Pulmonary Inflammation in a Rat Model

Objective. The present study was to investigate the feasibility of adenovirus-mediated small interference RNA (siRNA) targeting Toll-like receptor 4 (TLR4) gene in ameliorating lipopolysaccharide- (LPS-) induced acute lung injury (ALI). Methods. In vitro, alveolar macrophages (AMs) were treated with Ad-siTLR4 and Ad-EFGP, respectively, for 12 h, 24 h, and 48 h, and then with LPS (100 ng/mL) for 2 h, and the function and expression of TLR4 were evaluated. In vivo, rats received intratracheal injection of 300 μL of normal saline (control group), 300 μL of Ad-EGFP (Ad-EGFP group), or 300 μL of Ad-siTLR4 (Ad-siTLR4 group) and then were intravenously treated with LPS (50 mg/kg) to induce ALI. Results. Ad-siTLR4 treatment significantly reduced TLR4 expression and production of proinflammatory cytokines following LPS treatment both in vitro and in vivo. Significant alleviation of tissue edema, microvascular protein leakage, and neutrophil infiltration was observed in the AdsiTLR4-treated animals. Conclusion. TLR4 plays a critical role in LPS-induced ALI, and transfection of Ad-siTLR4 can effectively downregulate TLR4 expression in vitro and in vivo, accompanied by alleviation of LPS-induced lung injury. These findings suggest that TLR4 may serve as a potential target in the treatment of ALI and RNA interfering targeting TLR4 expression represents a therapeutic strategy

Chitosan-Templated Bio-coloration of Cotton Fabrics via Laccase-Catalyzed Polymerization of Hydroquinone

The file attached to this record is the author's final peer reviewed version. The Publisher's final version can be found by following the DOI link.There is an increasing interest in the development of enzymatic coloration of textile fabrics as an alternative to conventional textile dyeing processes, which is successful for dyeing protein fibers. However, unmodified cotton fabrics are difficult to be dyed through enzyme catalysis due to the lack of affinity of biosynthesized dyes to cotton fibers. In order to improve the enzyme‐catalyzed dyeability of cotton fibers, chitosan was used to coat cotton fabrics as template. A novel and facile bio‐coloration technique using laccase catalysis of hydroquinone was developed to dye chitosan‐templated cotton fabrics. The polymerization of hydroquinone with the template of chitosan under the laccase catalysis was monitored by ultraviolet‐vis spectrophotometer on the absorbance of reaction solution. A significant peak of UV‐vis spectrum at 246 nm corresponding to large conjugated structures appeared and increased with increasing the duration of enzymatic catalysis. The effect of different treatment conditions on the laccase‐catalyzed dyeing of cotton fabric was investigated to determine their optimal parameters of laccase‐catalyzed coloration. Fourier‐transform infrared spectroscopy spectra demonstrated the formation of H‐bond and Schiff base reaction between chitosan and polymerized hydroquinone. Scanning electron microscopy indicated that the surface of dyed cotton fiber was much rougher than that of the control sample. Moreover, X‐ray photoelectron spectroscopy also revealed the existence of the chitosan/polymerized hydroquinone complex and polymerized hydroquinone on the dyed cotton fibers. This chitosan‐templated approach offers possibility for biological dyeing coloration of cotton fabrics and other cellulosic materials

Anti-bacterial properties of lactoferrin immobilized wool fabric

A new biological cross-linker, microbial transglutaminase (mTGase), has been used to catalyze the immobilization of lactoferrin onto the wool fabrics, and the antibacterial properties of immobilized wool on both Gram-negative and Gram-positive bacteria are studied. It is found that the minimal inhibitory concentration of lactoferrin against S·aureus and E·coli is 0.5mg/mL and 0.25mg/mL respectively. As compared to the control sample, the amount of lactoferrin adhered onto the wool fabric improves from 4.87 mg.(g fabric)-1 to 12.96 mg.(g fabric)-1, indicating that the crosslinking reaction initiated by mTGase can increase the amount of lactoferrin fixed onto wool fabric obviously. The ratios of bacteriostasis to S.aureus and E.coli of wool fabrics immobilized with lactoferrin are bound to be 57.95% and 69.96% respectively, showing good antibacterial property

Effect of immobilized cellulase enzyme treatment on properties of ramie fabric

In this study, Eudragit S-100 has been covalently bound to the cellulase enzyme to form immobilized cellulase enzyme and then the effect of the treatment on ramie fabric properties is studied. The ramie fabrics treated with immobilized cellulase enzyme show lower quantities of reducing sugar, weight loss, and higher tensile strength than native cellulase enzyme-treated fabrics. Scanning electron microscopic analysis shows that the surface of ramie fabrics treated with cellulase enzyme is smoother than that of the untreated sample. Furthermore, treatment by the immobilized cellulase enzyme is less damaging to the fibres. X-ray diffraction studies show that there is hardly any loss in the crystallinity of ramie fabrics. Low-stress mechanical properties evaluated by the Kawabata Evaluation System for Fabric indicate that immobilized cellulase enzyme treatment improves the softness, flexibility, and elastic recovery of the ramie fabrics

Enzyme-mediated surface modification of jute and its influence on the properties of jute/epoxy composites

Surface modification of jute fibers is necessary to improve the adhesion and interfacial compatibility between fibers and resin matrix before using fibers in polymer composites. In this study, dodecyl gallate (DG) was enzymatically grafted onto the jute fiber by laccase to endow the fiber with hydrophobicity. A hand lay-up technique was then adopted to prepare jute/epoxy composites. Contact angle and wetting time measurements showed that the surface hydrophobicity of the jute fabric was increased after the enzymatic graft modification. The water absorption and thickness swelling of the DG-grafted jute fabric/epoxy composite were lower than those of the other composites. The tensile and dynamic mechanical properties of the jute/epoxy composites were enhanced by the surface modification. Scanning electron microscopy images revealed stronger fibermatrix adhesion in composites with modified fibers. Therefore, the enzymatic graft modification increased the fibermatrix interface area. The fibermatrix adhesion was enhanced, and the mechanical properties of the composites were improved.Contract grant sponsor: National Natural Science Foundation of China; contract grant number: 51173071; contract grant sponsor: Program for New Century Excellent Talents in University; contract grant number: NCET-12-0883; contract grant sponsor: Fundamental Research Funds for the Central Universities; contract grant sponsor: JUSRP51312B.info:eu-repo/semantics/publishedVersio

Laccase-mediated dye-free coloration of wool fabric

In this study, an investigation on a novel coloring technique, based on laccase-mediated radical coupling of amino acidmolecules of wool fibres, has been carried out. Firstly, the influence of temperature, incubation time, and pH on the K/Svalue and hue angle (h) of the colored wool fabrics is studied. Analysis of levelness of coloration, wash fastness, rubfastness, and UV-protection factor of the colored wool fabrics has been done. Then, the surface morphology and structure ofthe wool fibres are analyzed by scanning electron microscopy (SEM) and Fourier transform Infrared spectroscopy (FTIR).The enzymatic coloration processes are carried out in an acetate-sodium acetate buffer medium (pH 5) at 50 C for 24 h andthe colored wool fabrics show good color fastness and uniformity. The results obtained are as per the requirements of textilecolor fastness. SEM study shows that no particles are adhered to the surface of the wool fibres. The results of FTIR andultraviolet-visible spectroscopy show that the obvious oxidation coupling reactions take place between the molecules in thepolypeptide chains of the wool