Antibacterial PET Fabrics Modified with Quaternary Ammonium Functionalized Hyperbranched Polymers via Electron Beam Radiation

Shumin Zhang,Fang Ding,Zhiguang Li,Xuehong Ren,Tung-Shi Huang 한국섬유공학회 2020 Fibers and polymers Vol.21 No.10

The numerous functional groups and dendritic structure of hyperbranched polymers render them for a wide rangeof applications. In this study, hyperbranched polymer Boltorn H20, containing abundant hydroxyl groups, was modified toprepare quaternary ammonium functionalized hyperbranched polymers, QAS-HPs. The synthesized QAS-HPs were coatedon polyethylene terephthalate (PET) fabrics by electron beam radiation. The PET fabrics were endowed antimicrobial andhydrophilic properties after modification. The water contact angles of the modified PET fabrics were tested, and the resultsshowed significant improvement in hydrophilicity. The results of antibacterial efficacy tests showed that the modified PETfabrics could inactivate 100 % of Staphylococcus aureus (S.aureus) and 90.8 % of Escherichia coli O157:H7 (E. coliO157:H7) with 30 min of contact time.

Antibacterial and Hydrophilic Modification of PET Fabrics by Electron Beam Irradiation Process

Shumin Zhang,Fang Ding,Yingfeng Wang,Xuehong Ren,Tung-Shi Huang 한국섬유공학회 2020 Fibers and polymers Vol.21 No.5

Electron beam (EB) irradiation has been utilized to modify materials for various applications due to its remarkableadvantages. As an efficient and environmental-friendly way for antibacterial and hydrophilic purposes, EB irradiation wasapplied to modify polyethylene terephthalate (PET) fabrics by grafting with a N-halamine precursor monomer 3-allyl-5,5-dimethylhydantoin (ADMH) and acrylic acid (AA) in this study. The grafted PET fabrics were loaded with silver ions tofurther enhance the antimicrobial efficacy. The hydrophilicity of the modified PET fabrics was evaluated by testing the watercontact angles with different contact times. The breaking strength and thermal stability of the modified swatches werestudied. The UVA light stability results showed the chlorine loading of the modified PET fabrics decreased with the extensionof UVA exposure time, and most chlorine loading could be recovered by re-chlorination. The antibacterial test showed thatthe modified PET swatches can inactivate all inoculated S. aureus and E. coli with short contact times.

Optimal Selection of Agricultural Products to Inhibit Citrinin Production during Submerged Culture of Monascus anka

Xu Xiong,Xuehong Zhang,Zhenqiang Wu,Zhilong Wang 한국생물공학회 2014 Biotechnology and Bioprocess Engineering Vol.19 No.6

Agricultural products exhibit a “buffering nature”during autoclaving and fermentation processes: i.e., thefinal pH of agricultural product medium after Monascusfermentation maintains a certain value. The protein contentof agricultural products strongly affects the bufferingcapacity and an extremely low final pH, below 3, can beachieved by the selection of agricultural products with lowprotein content, such as rice meal and cornmeal. This lowpH can be used to inhibit citrinin biosynthesis duringMonascus fermentation. Thus, optimal selection of agriculturalproducts with low protein content may provide a novelstrategy to inhibit citrinin production in submerged cultureof Monascus anka at a low initial pH for the production ofMonascus pigments. pH values ranging from 2.6 to 3 canbe maintained in Monascus fermentation using cornmeal/wheat starch (30:30 g/L) as substrate at initial pH 2.5,where the concentration of intracellular pigments reaches45 AU at 470 nm while citrinin is undetectable by TLCanalysis.

Energy Efficiency Analysis and Optimization of Multiantenna Heterogeneous Cellular Networks Modeled by Matérn Hard-core Point Process

( Yonghong Chen ),( Jie Yang ),( Xuehong Cao ),( Shibing Zhang ) 한국인터넷정보학회 2020 KSII Transactions on Internet and Information Syst Vol.14 No.8

The Poisson point process (PPP) is widely used in wireless network modeling and performance analysis because it can provide tractable results for heterogeneous cellular networks (HetNets) analysis. However, it cannot accurately reflect the spatial distribution characteristics of the actual base stations (BSs). Considering the fact that the distribution of macro base stations (MBSs) is exclusive, the deployment of MBSs is modeled by the Matérn hard-core point process (MHCPP), and the deployment of pico base stations (PBSs) is modeled by PPP. This paper studies the performance of multiantenna HetNets and improves the energy efficiency (EE) of HetNets by optimizing the transmit power of PBSs. We use a simple approximate method to study the signal-to-interference ratio (SIR) distribution in two-tier MHCPP-PPP HetNets and derive the coverage probability, average data rate and EE of HetNets. Then, an optimization algorithm is proposed to improve the EE of HetNets. Finally, three transmission technologies are simulated and analyzed. The results show that multiantenna transmission has better system performance than single antenna transmission and that selecting the appropriate transmit power for a PBS can effectively improve the EE of the system. In addition, two-tier MHCPP-PPP HetNets have higher EE than two-tier PPP-PPP HetNets.

Durable N-halamine Antibacterial Cellulose Based on Thiol-ene Click Chemistry

Zhipeng Ma,Maoli Yin,Mengshuang Zhang,Zhenming Qi,Xuehong Ren,Tung-Shi Huang 한국섬유공학회 2019 Fibers and polymers Vol.20 No.2

Antibacterial cotton fabrics were prepared with 3-allyl-5,5-dimethylhydantoin (ADMH) by UV photoinitiated thiol-ene click chemistry after 3-mercaptopropyltriethoxysilane (MPTES) was introduced on the surface of cotton fabrics. The treated cotton fabrics were characterized by SEM, FT-IR and EDS. After chlorination with diluted sodium hypochlorite, the treated samples showed good antibacterial efficacy against S. aureus and E. coli O157:H7. About 106 of S. aureus and E. coli O157:H7 could be completely inactivated within 1 min and 5 min of contact, respectively. Compared to the control samples, the antibacterial treatment method used in this study only had a minor effect on the tensile strength of cotton fabrics. Besides, the treated cotton fabrics showed good storage stability and 77 % of the active chlorine remained after 30 days. After exposure to bleach solution, almost all of the active chlorine was restored. The prepared antimicrobial cotton fabrics showed good washing and UV light stability.

Functionalization of PET fabric via silicone based organic–inorganic hybrid coating

Que Kong,Zhiguang Li,Zuoliang Zhang,Xuehong Ren 한국공업화학회 2020 Journal of Industrial and Engineering Chemistry Vol.83 No.-

In this paper, silica dioxide nanoparticles (SiO2) were synthesized and functionalized with noctadecyltriethoxysilane(OD) through a modified Stöber method for the preparation of organic–inorganic hybrid micro-nanoparticles. Organic–inorganic hybrid micro-nanoparticles were applied ontothe polyester (PET) fabric via a conventional “dipping–drying” process for thefluoro-free water-repellenttextile materials. The coated PET fabric surface showed micro/nano-structures and exhibitedhydrophobic behavior with water contact angle of 141 . The surface morphologies, surface chemicalcomposition and contact angles of the coated fabrics surface were measured. Furthermore, the dynamichydrophobic behavior of water droplet impact on the fabric was investigated. By analyzing the energychange, D(t)/D0 value and H(t)/D0 value during water droplet impact were measured. The water dropletshowed an obvious effect of the dynamic rebound behavior on the coated fabric surface, furtherconfirming that the coated PET fabric had hydrophobicity. After the rubbing and washing durability,mechanical and chemical stability treatment, the coated PET fabrics still maintained high hydrophobicityand displayed good water-repellent durability. Last but not least, PET hydrophobic fabrics exhibitedexcellent self-cleaning properties with dyes on the fabric surface.

A Prospective Cohort Study of Red Meat Consumption and Non-Alcoholic Fatty Liver Disease Risk Among Women

( Mi Na Kim ),( Chun-han Lo ),( Kathleen E. Corey ),( Xiao Luo ),( Xuehong Zhang ),( Andrew T. Chan ),( Tracey G. Simon ) 대한간학회 2020 춘·추계 학술대회 (KASL) Vol.2020 No.1

Aims: Previous studies have suggested consumption of red meat might be associated with an increased risk of developing nonalcoholic fatty liver disease (NAFLD). However, large-scale, prospective data regarding red meat consumption in relation to the incidence of NAFLD are lacking, nor is it known whether this association is mediated by obesity. Methods: This prospective cohort study included 77,795 women in the Nurses’ Health Study II cohort without NAFLD at baseline (in 1995), who provided detailed, validated information regarding diet, including consumption of red meat, every 4 years, through 2015. Lifestyle factors, clinical comorbidities and body mass index (BMI), were updated biennially. Cox proportional hazard models were used to estimate multivariable adjusted hazard ratios (aHRs) and 95% confidence intervals (CIs). Results: Over 1,444,637 person years of follow-up, we documented 3,130 cases of incident NAFLD. Women consuming ≥2 servings of red meat per day had a 56% higher risk of developing incident NAFLD compared to women consuming ≤1 serving per week (95% CI, 1.26-1.93), after multivariable adjustment. Similarly, significant and positive associations were observed for both unprocessed and processed red meat (both P-trend< 0.0001). However, after further adjustment for BMI, all associations for red meat, including unprocessed and processed red meat, were attenuated and not statistically significant (all P-trend >0.05). BMI was estimated to mediate 66% (95% CI, 41.9%-83.9%; P<0.0001) of the association between red meat consumption and NAFLD risk. Conclusions: Red meat consumption, including both unprocessed and processed red meat, was associated with significantly increased risk of developing NAFLD. This association was mediated largely by obesity.

Long-Term Use of Antibiotics and the Risk of Non-Alcoholic Fatty Liver Disease: A Prospective Cohort Study among Women

( Mi Na Kim ),( Chun-han Lo ),( Kathleen E. Corey ),( Xuehong Zhang ),( Andrew T. Chan ),( Tracey G. Simon ) 대한간학회 2020 춘·추계 학술대회 (KASL) Vol.2020 No.1

Aims: Gut microbial dysbiosis is associated with the development of nonalcoholic fatty liver disease (NAFLD). Antibiotics can alter the composition of the gut microbiota. However, the association of antibiotic use with the risk of NAFLD has not been clarified in a population at usual risk. We investigated the association of the duration of antibiotic use in different phases of adulthood with the risk of NAFLD. Methods: This study included 68,644 women in the Nurses’ Health Study II cohort without NAFLD at baseline (in 2005). Participants were followed prospectively through 2015. In the 2005 questionnaire, women were asked to indicate the cumulative amount of antibiotic use at age 20-39 years (young adulthood) or 40-49 years (middle adulthood). Cox proportional hazard models were used to estimate multivariable adjusted hazard ratios (aHRs) and 95% confidence intervals (CIs). Results: Over a total of 534,644 person-years, we documented 1,944 incident cases of NAFLD. Compared to women with no antibiotic use during young adulthood, use of long-term antibiotics for ≥2 months was associated with significantly increased risk of incident NAFLD (multivariable aHR 1.48, 95% CI 1.03- 2.11). In analyses focused on middle adulthood, compared to women who did not use antibiotics during middle adulthood, those with both short-term (<2 months) and long-term (≥2 months) antibiotics use had significantly increased risk of incident NAFLD (multivariable aHRs, 1.32 [95% CI 1.01-1.72] and 1.83 [95% CI 1.37-2.45], respectively). Conclusions: In conclusion, long-term antibiotic use in both young and middle adulthood was associated with a significantly increased risk of developing incident NAFLD. These findings support the potential role of the gut microbiota in the pathogenesis of NAFLD.