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Research on the improvement of efficiency in the manufacturing industry is underdeveloped partly because of the ambiguous objectives of the technical development of efficiencies in terms of energy consumption reduction. Consequently, the technical development of high-efficiency techniques that consider the whole manufacturing system is rarely addressed in industrial research. For this reason, this report aims to find the patterns in, and the definitions of, the technologies that will lead to efficiency improvement in the entire manufacturing industry by thoroughly investigating the literature about energy consumption reduction strategies, energy policies, and the state-of-the-art for energy-saving methods that are being pursued currently in several major countries. Through this study, the necessity and importance of the foregoing three items have been identified, and a way of defining the productivities of an energy-saving manufacturing system distinct from those of conventional manufacturing systems was attempted. It is also shown that the development of energy-saving and energy-harvesting technologies for all industrial sectors has emerged as a herald of economic growth in the near future.

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Escherichia coli (EHEC) and Shigella dysenteriae serotype 1 are enterohemorrhagic bacteria that induce hemorrhagic colitis. This, in turn, may result in potentially lethal complications, such as hemolytic uremic syndrome (HUS), which is characterized by thrombocytopenia, acute renal failure, and neurological abnormalities. Both species of bacteria produce Shiga toxins (Stxs), a phage-encoded exotoxin inhibiting protein synthesis in host cells that are primarily responsible for bacterial virulence. Although most studies have focused on the pathogenic roles of Stxs as harmful substances capable of inducing cell death and as proinflammatory factors that sensitize the host target organs to damage, less is known about the interface between the commensalism of bacterial communities and the pathogenicity of the toxins. The gut contains more species of bacteria than any other organ, providing pathogenic bacteria that colonize the gut with a greater number of opportunities to encounter other bacterial species. Notably, the presence in the intestines of pathogenic EHEC producing Stxs associated with severe illness may have compounding effects on the diversity of the indigenous bacteria and bacterial communities in the gut. The present review focuses on studies describing the roles of Stxs in the complex interactions between pathogenic Shiga toxin-producing E. coli, the resident microbiome, and host tissues. The determination of these interactions may provide insights into the unresolved issues regarding these pathogens.

Background/Aims: β₂-Microglobulin (β₂-M) is a surrogate marker of middle-molecule uremic toxins and is associated with mortality in chronic hemodialysis patients. However, the impact of serum β₂-M levels on mortality in peritoneal dialysis (PD) patients is uncertain. The purpose of this study was to examine the association of serum β₂-M levels with all-cause mortality in PD patients. Methods: A total of 771 PD patients were selected from the Clinical Research Center registry for end-stage renal disease cohort in Korea. Patients were categorized into 3 groups by tertiles of serum β₂-M levels. The primary outcome was all-cause mortality. Results: The median value of serum β₂-M was 23.6 mg/l (interquartile range 14.8-33.4 mg/l), and the median follow-up period was 39 months. The Kaplan-Meier analysis showed that the all-cause mortality rate was significantly different according to tertiles of serum β₂-M in PD patients (p = 0.03, log-rank). Multivariate Cox proportional analysis showed that the hazards ratio for all-cause mortality was 1.02 (95% CI 1.01-1.04, p = 0.006) per 1 mg/l increase in β₂-M after adjustment for multiple confounding factors that relate to malnutrition and inflammation marker. However, serum β₂-M was not associated with all-cause mortality after adjustment for residual renal clearance. Conclusions: These results are supportive of the potential role of the serum β₂-M level as a predictor of mortality in PD patients.

Novel biodegradable molecularly imprinted polymers (MIPs) based on poly(ε-caprolactone) (PCL) were prepared by combining two important properties required of ideal biomaterials, biodegradability (with biocompatibility) and molecular recognition properties. Acrylate or methacrylate end-capped PCL macromers were synthesized through the reaction of PCL diol or triol with acryloyl or methacryloyl chloride. The synthesis of acrylate or methacrylate end-capped macromers was confirmed using FT-IR and 1 H NMR spectroscopic techniques. These macromers were used to prepare biodegradable crosslinked networks by photopolymerization with functional monomer (acrylic acid) and a model template (theophylline). The theophylline-imprinted polymer showed higher binding capacity for theophylline compared with nonimprinted polymer (NIP), and also showed selectivity for theophylline over caffeine (similar structure molecules). PCLbased MIP degraded 8% of the initial weight in 30 days in phosphate-buffered saline (PBS) solution (pH 7.4) and over 90% of the initial weight within 24 h in 1 N NaOH at 37 o C. © KSBB Keywords: molecularly imprinted polymer, biodegradable, poly(ε-caprolactone) = = = =

Background Styrene is a large-volume commodity petrochemical, which has been used in a wide range of polymer industry as the main building block for the construction of various functional polymers. Despite many efforts to produce styrene in microbial hosts, the production titers are still low and are not enough to meet the commercial production of styrene. Results Previously, we developed a high l -phenylalanine producer ( E. coli YHP05), and it was used as a main host for de novo synthesis of styrene. First, we introduced the co-expression system of phenylalanine-ammonia lyase ( PAL ) and ferulic acid decarboxylase ( FDC ) genes for the synthesis of styrene from l -phenylalanine. Then, to minimize cell toxicity and enhance the recovery of styrene, in situ product recovery (ISPR) with n -dodecane was employed, and culture medium with supplementation of complex sources was also optimized. As a result, 1.7 ± 0.1 g/L of styrene was produced in the flask cultures. Finally, fed-batch cultivations were performed in lab-scale bioreactor, and to minimize the loss of volatile styrene during the cultivation, three consecutive bottles containing n-dodecane were connected to the air outlet of bioreactor for gas-stripping. To conclude, the total titer of styrene was as high as 5.3 ± 0.2 g/L, which could be obtained at 60 h. Conclusion We successfully engineered E. coli strain for the de novo production of styrene in both flask and fed-batch cultivation, and could achieve the highest titer for styrene in bacterial hosts reported till date. We believe that our efforts in strain engineering and ISPR strategy with organic solvent will provide a new insight for economic and industrial production of styrene in a biological platform. Electronic supplementary material The online version of this article (10.1186/s12934-019-1129-6) contains supplementary material, which is available to authorized users.

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