Organ-Level Functional 3D Tissue Constructs with Complex Compartments and their Preclinical Applications

There is an increasing interest in organ-level 3D tissue constructs, owing to their mirroring of in vivo-like features. This has resulted in a wide range of preclinical applications to obtain cell- or tissue-specific responses. Additionally, the development and improvement of sophisticated technologies, such as organoid generation, microfluidics, hydrogel engineering, and 3D printing, have enhanced 3D tissue constructs to become more elaborate. In particular, recent studies have focused on including complex compartments, i.e., vascular and innervation structured 3D tissue constructs, which mimic the nature of the human body in that all tissues/organs are interconnected and physiological phenomena are mediated through vascular and neural systems. Here, the strategies are categorized according to the number of dimensions (0D, 1D, 2D, and 3D) of the starting materials for scaling up, and novel approaches to introduce increased complexity in 3D tissue constructs are highlighted. Recent advances in preclinical applications are also investigated to gain insight into the future direction of 3D tissue construct research. Overcoming the challenges in improving organ-level functional 3D tissue constructs both in vitro and in vivo will ultimately become a life-saving tool in the biomedical field.     

Human‐Iris‐Like Aperture and Sphincter Muscle Comprising Hyperelastic Composite Hydrogels Containing Graphene Oxide

Soft hydrogels are extensively studied for developing human‐body‐mimicking actuators because of their stimuli‐responsive volume change and elasticity. Mimicking a human eye with hydrogels is very challenging because both the large variation in the volume and the high modulus of the gels should be concurrently achieved. In the human eye, adjusting the iris for controlling the focal point and light transmittance is achieved by the contraction of the sphincter muscle. In this work, a hyperelastic poly(N‐isopropylacrylamide) containing graphene oxide (PNIPAm/GO) composite hydrogels, which exhibits a thermo‐responsive volume phase transition is developed. The fact that the inner hole size for center‐cut hydrogels can increase or decrease during heating depending on the geometry of the hydrogels is revealed. Based on these findings, human‐iris‐like actuators capable of controlling the shape of a polydimethylsiloxane (PDMS) lens for adjusting magnification of an object is developed. When heated, the hyperelastic hydrogels act like the sphincter muscle in the eye, inducing the curvature change of the attached PDMS lens. Thus, hyperelastic hydrogels of large variation can provide an efficient platform to fabricate various soft actuation systems.     

A decoupling strategy for protecting sensitive process information in cooperative optimization of power flow

Optimal power flow (OPF) with close cooperation between the power grid and flexible electricity-intensive chemical processes can reduce costs for the grid and for electricity users. However, this would require sharing detailed chemical process models, which may reveal confidential information and potentially jeopardize competitive advantages for a chemical process operator. We propose an algorithm that enables economically advantageous cooperation without the need to exchange sensitive information. Low-order linear models are used to represent the dynamic behavior of electricity-intensive processes. We integrate these models into the OPF problem and solve the problem using a decoupling strategy based on Benders-type cuts. The cuts introduce limited communication between the chemical processes and the grid without exchanging explicit information pertaining to the process dynamics and performance. Our results reproduce solutions obtained by sharing detailed process models up to a user-defined optimality gap for several test cases that reflect both normal and congested grid states. We also investigate the trade-off between the value of the optimality gap and computational effort. Finally, we study the scaling behavior of the iterative procedure with respect to flexible loads at multiple grid locations.     

Combining Everolimus and Ku0063794 Promotes Apoptosis of Hepatocellular Carcinoma Cells via Reduced Autophagy Resulting from Diminished Expression of miR-4790-3p

It is challenging to overcome the low response rate of everolimus in the treatment of patients with hepatocellular carcinoma (HCC). To overcome this challenge, we combined everolimus with Ku0063794, the inhibitor of mTORC1 and mTORC2, to achieve higher anticancer effects. However, the precise mechanism for the synergistic effects is not clearly understood yet. To achieve this aim, the miRNAs were selected that showed the most significant variation in expression according to the mono- and combination therapy of everolimus and Ku0063794. Subsequently, the roles of specific miRNAs were determined in the processes of the treatment modalities. Compared to individual monotherapies, the combination therapy significantly reduced viability, increased apoptosis, and reduced autophagy in HepG2 cells. The combination therapy led to significantly lower expression of miR-4790-3p and higher expression of zinc finger protein225 (ZNF225)—the predicted target of miR-4790-3p. The functional study of miR-4790-3p and ZNF225 revealed that regarding autophagy, miR-4790-3p promoted it, while ZNF225 inhibited it. In addition, regarding apoptosis, miR-4790-3p inhibited it, while ZNF225 promoted it. It was also found that HCC tissues were characterized by higher expression of miR-4790-3p and lower expression of ZNF225; HCC tissues were also characterized by higher autophagic flux. We, thus, conclude that the potentiated anticancer effect of the everolimus and Ku0063794 combination therapy is strongly associated with reduced autophagy resulting from diminished expression of miR-4790-3p, as well as higher expression of ZNF225.     

Production of 6,8-Dihydroxy Fatty Acids by Recombinant Escherichia coli Expressing T879A Variant 6,8-Linoleate Diol Synthase from Penicillium oxalicum

Recombinant Escherichia coli expressing T879A variant 6,8-linoleate diol synthase (LDS) from Penicillium oxalicum showed 2.1-fold higher activity than recombinant E. coli expressing wild-type 6,8-LDS for the production of 6,8-dihydroxy fatty acids (DiHFA) from linoleic acid. The optimal conditions for the production of 6,8-DiHFA by recombinant E. coli expressing T879A variant 6,8-LDS were pH 6.5, 35°C, 50 g L⁻¹ cells, 10 g L⁻¹ (35.7 mM) substrate, and 5% (v/v) dimethyl sulfoxide. Under these optimized conditions, 6.6 g L⁻¹ (22.1 mM) 6,8-dihydroxy-9,12(Z,Z)-octadecadienoic acid (DiHODE) and 7.1 g L⁻¹ (22.6 mM) 6,8-dihydroxy-9(Z)-octadecenoic acid (DiHOME) were produced from linoleic acid and oleic acid in 40 min, respectively. The volumetric productivities of 6,8-DiHODE and 6,8-DiHOME under these conditions were 9.9 and 10.7 mg L⁻¹ h⁻¹, respectively. The volumetric productivities of 6,8-DiHODE and 6,8-DiHOME were the highest values among those of all reported regiospecific DiHODE and DiHOME, respectively. To the best of our knowledge, this is the first quantitative biotechnological production of 6,8-DiHFA.     

Semantic Hashtag Relation Classification Using Co-occurrence Word Information

Wireless Personal Communications - Users using social networking service (SNS) may express their thoughts and feelings using simple hashtags. Hashtags are related to other hashtags and images that...     

Exogenous β-mannanase supplementation improved immunological and metabolic responses in lactating dairy cows

Exogenous enzymes have been used to improve nutrient utilization in several species of livestock, particularly swine and poultry. In addition, improved immunological and metabolic traits have been reported in nonruminants. The objective of this study was to determine the effects of β-mannanase supplementation on milk yield and composition, and immunological and metabolic responses in lactating Holstein dairy cows. Two weeks after calving, 20 Holstein cows (10 multiparous and 10 primiparous) were blocked by parity and assigned to 1 of 2 diets for 182 d. All cows were housed in the same environment and fed the same basal diet. The basal diet of the treatment group was supplemented with β-mannanase (CTCBio Inc., Seoul, South Korea) at 0.1% of concentrate dry matter. No differences were detected between the control and enzyme supplement groups in milk yield parameters or milk composition. Supplementation of β-mannanase enzyme reduced blood haptoglobin levels in supplemented multiparous cows compared with controls. Furthermore, nonesterified fatty acid concentration levels tended to be lower in cows fed β-mannanase, regardless of parity. Neither immunoglobulin G nor milk somatic cell count was affected by β-mannanase supplementation, regardless of parity. The number of insemination services tended to be lower in cows fed diets supplemented with β-mannanase. Results from this study suggest that supplementation of β-mannanase exogenous enzyme could help to reduce instances of systemic inflammation and decrease fat mobilization in lactating Holstein cows. Multiparous cows are considered susceptible to acute infections and inflammation; thus, the enzyme had a greater effect in multiparous cows.     

Syngas production through gasification of coal water mixture and power generation on dual-fuel diesel engine

In the present study, a syngas was produced by preparing coal water mixtures of two different concentrations and gasifying the coal water mixtures. An entrained-flow gasifier of 1 ton/day scale was used and, after undergoing a purification process, the produced syngas was applied to a modified diesel engine for power generation. As the gasification temperature increased, the carbon conversion and the cold gas efficiency were found to increase. In the composition of the produced syngas, the content of H₂ remained constant, that of CO increased, and those of CO₂ and CH₄ decreased. The carbon conversion increased with equivalence ratio. A maximum cold gas efficiency of 66.1% was found at the equivalence ratio of 0.43. N₂ was additionally supplied to verify the gasification characteristics depending on the gas feed flow rate. The optimum feed flow rate was verified at different slurry concentrations and equivalence ratio. The produced syngas was supplied to a modified diesel engine and operated depending on the syngas feed flow rate and the engine operation conditions. The brake thermal efficiency of the engine was constant regardless of the syngas feed flow rate. The diesel engine showed high efficiency despite the mixing of the syngas.     

Crossflow microfiltration of yeast suspensions in tubular filters

Crossflow microfiltration experiments were performed on yeast suspensions through 0.2-microns pore size ceramic and polypropylene tubes at various operating conditions. The initial transient flux decline follows dead-end filtration theory, with the membrane resistance determined from the initial flux and the specific cake resistance determined from the rate of flux decline due to cake buildup. For long times, the observed fluxes reach steady or nearly steady values, presumably as a result of the cake growth being arrested by the shear exerted at its surface. The steady-state fluxes increase with increasing shear rate and decreasing feed concentration, and they are nearly independent of transmembrane pressure. The steady-state fluxes for unwashed yeast in deionized water or fermentation media are typically 2-4 times lower than those predicted by a model based on the properties of nonadhesive, rigid spheres undergoing shear-induced back-diffusion. In contrast, the steady-state fluxes observed for washed yeast cells in deionized water are only 10-30% below the predicted values. The washed yeast cells also exhibited specific cake resistances that are an order of magnitude lower than those for the unwashed yeast. The differences are due to the presence of extracellular proteins and other macromolecules in the unwashed yeast suspensions. These biopolymers cause higher cell adhesion and resistance in the cake layer, so that the cells at the top edge are not free to diffuse away. This is manifested as a concentration jump from the edge of the cake layer to the sheared suspension adjacent to it.(ABSTRACT TRUNCATED AT 250 WORDS)