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In this work, silver nitrate, thiourea, bisphenol A diglycidyl ether (BADGE), and propylene glycol methyl ether (PM) were selected for designing a silver(I)-complex to trigger the deposition of inductance coil on PET film through electroless copper plating. The most stable silver(I)-complex structure is formed when the ratio of thiourea molecules and silver ions is 3 to 1 by quantum chemical calculations based on density functional theory (DFT). Meanwhile, XRD test demonstrates that the white precipitate crystallized from PM solution of thiourea and silver nitrate is [Ag(SC(NH2)2)3]NO3, which is consistent with theoretical calculations. The cross section of PET film with copper patterns and interconnection holes characterized by metallurgical microscope proves that the silver(I)-complex is able to initiate copper deposition on the surface and through hole wall of PET film. The measured inductance values at operating frequency from 1 to 50 MHz indicate that the fabricated flexible inductor is capable of being integrated into flexible electronics when the bending angles are within 45°. Additionally, the inductor can also be utilized as an angel sensor when the bending angles are in the range of 60° to 180° at 10 MHz.

The traditional strategy to improve the efficiency of an entire coupled enzyme system relies on separate direction of the evolution of enzymes involved in their respective enzymatic reactions. This strategy can lead to enhanced single-enzyme catalytic efficiency but may also lead to loss of coordination among enzymes. This study aimed to overcome such shortcomings by executing a directed evolution strategy on multiple enzymes in one combined group that catalyzes the asymmetric biosynthesis of l-phosphinothricin. The genes of a glutamate dehydrogenase from Pseudomonas moorei (PmGluDH) and a glucose dehydrogenase from Exiguobacterium sibiricum (EsGDH), along with other gene parts (promoters, ribosomal binding sites (RBSs), and terminators) were simultaneously evolved. The catalytic efficiency of PmGluDH was boosted by introducing the beneficial mutation A164G (from 1.29 s-1mM-1 to 183.52 s-1mM-1), and the EsGDH expression level was improved by optimizing the linker length between the RBS and the start codon of gdh. The total turnover numbers of the bioreaction increased from 115 (GluDH WTNADPH) to 5846 (A164GNADPH coupled with low expression of EsGDH), and to 33950 (A164GNADPH coupled with high expression of EsGDH). The coupling efficiency was increased from ∼30% (GluDH_WT with low expression of GDH) to 83.3% (GluDH_A164G with high expression of GDH). In the batch production of l-phosphinothricin utilizing whole-cell catalysis, the strongest biocatalytic reaction exhibited a high space-time yield (6410 g·L-1·d-1) with strict stereoselectivity (>99% enantiomeric excess).Importance: The traditional strategy to improve multienzyme-catalyzed reaction efficiency may lead to enhanced single-enzyme catalytic efficiency but may also result in loss of coordination among enzymes. We describe a directed evolution strategy of an entire coupled enzyme system to simultaneously enhance enzyme coordination and catalytic efficiency. The simultaneous evolution strategy was applied to a multienzyme-catalyzed reaction for the asymmetric synthesis of l-phosphinothricin, which not only enhanced the catalytic efficiency of GluDH but also improved the coordination between GluDH and GDH. Since this strategy is enzyme-independent, it may be applicable to other coupled enzyme systems for chiral chemical synthesis.

Altered mitochondrial dynamics are commonly seen in tumors and Parkinson’s disease (PD), but the exact mechanism is unclear. We observed in tumor and PD flies, interference of mitochondrial fission or fusion reverses metabolic reprogramming and attenuates pathogenic phenotypes, indicating the rebalanced mitochondrial dynamics can re-establish cellular homeostasis. Surprisingly, we found Hsp22 is highly induced in tumor and PD flies. Hence, Hsp22 overexpression, not only suppressed RAS tumor flies, hepatocellular carcinoma mice, but also rescued PINK1B9 PD flies associating with restored mitochondrial homeostasis and reversing metabolic reprogramming. We speculate that mitochondrial dynamics is normally in a constant dynamic equilibrium, as if on a continually oscillating seesaw, tumor and PD are like the two extreme states of the seesaw which can be corrected by the promising target, Hsp22.One Sentence SummaryMitochondrial dynamics defects including tumor and PD lead to metabolic reprogramming accompanied with Hsp22 induction, vice versa, overexpression of Hsp22 reverses the mitochondrial dynamic dysfunction caused pathogenic metabolism.

Biosynthesizing unnatural chiral amino acids is challenging due to the limited reductive amination activity of amino acid dehydrogenase (AADH). Here, for the asymmetric synthesis of l -phosphinothricin from 2-oxo-4-[(hydroxy)(methyl)phosphinoyl]butyric acid (PPO), a glutamate dehydrogenase gene (named GluDH3) from Pseudomonas monteilii was selected, cloned and expressed in Escherichia coli (E. coli). To boost its activity, a “two-step”-based computational approach was developed and applied to select the potential beneficial amino acid positions on GluDH3. l -phosphinothricin was synthesized by GluDH-catalyzed asymmetric amination using the d -glucose dehydrogenase from Exiguobacterium sibiricum (EsGDH) for NADPH regeneration. Using lyophilized E. coli cells that co-expressed GluDH3_V375S and EsGDH, up to 89.04 g L−1 PPO loading was completely converted to l -phosphinothricin within 30 min at 35 °C with a space-time yield of up to 4.752 kg·L−1·d−1. The beneficial substitution V375S with increased polar interactions between K90, T193, and substrate PPO exhibited 168.2-fold improved catalytic efficiency (kcat/KM) and 344.8-fold enhanced specific activity. After the introduction of serine residues into other GluDHs at specific positions, forty engineered GluDHs exhibited the catalytic functions of “glufosinate dehydrogenase” towards PPO.

PurposeCopper electrodeposition acts as a crucial step in the manufacture of high-density interconnect board. The stability of plating solution and the uniformity of copper electrodeposit are the hotspot and difficulty for the research of electrodeposition. Because a large number of factors are included in electrodeposition, experimentally determining all parameters and electrodeposition conditions becomes unmanageable. Therefore, a multiphysics coupling technology was introduced to investigate microvia filling process, and the mechanism of copper electrodeposition was analyzed. The results provide a strong theoretical basis and technical guidance for the actual electroplating experiments. The purpose of this paper is to provide an excellent tool for quickly and cheaply studying the process behavior of copper electrodeposition without actually needing to execute time-consuming and costly experiments.Design/methodology/approachThe interactions among additives used in acidic copper plating solution for microvia filling and the effect on the copper deposition potential were characterized through galvanostatic measurement (GM). The adsorption behavior and surface coverage of additives with various concentrations under different rotating speeds of working electrode were investigated using cyclic voltammetry (CV) measurements. Further, a microvia filling model was constructed using multiphysics coupling technology based on the finite element method.FindingsGM tests showed that accelerator, inhibitor and leveler affected the potential of copper electrodeposition, and bis(3-sulfopropyl) disulfide (SPS), ethylene oxide-propylene oxide (EO/PO) co-polymer, and self-made leveler were the effective additives in acidic copper plating solution. CV tests showed that EO/PO–Cu+-Cl−complex was adsorbed on the electrode surface by intermolecular forces, thus inhibiting copper electrodeposition. Numerical simulation indicated that the process of microvia filling included initial growth period, the outbreak period and the stable growth period, and modeling result was compared with the measured data, and a good agreement was observed.Research limitations/implicationsThe research is still in progress with the development of high-performance computers.Practical implicationsA multiphysics coupling platform is an excellent tool for quickly and cheaply studying the electrodeposited process behaviors under a variety of operating conditions.Social implicationsThe numerical simulation method has laid the foundation for mechanism of copper electrodeposition.Originality/valueBy using multiphysics coupling technology, the authors built a bridge between theoretical and experimental study for microvia filling. This method can help explain the mechanism of copper electrodeposition.

Methyltriethoxysilane-treated BaFe12O19 particles were added into poly (phenylene oxide) (PPO) to obtain a composite system in the condition of benzoyl peroxide as an initiator. Thermal stability, structure, mechanical behavior and dielectric and magnetic properties were characterized to investigate the effects of BaFe12O19 particles on the performance of PPO-based composites. BaFe12O19/PPO composites were employed as embedded magnetic core to enhance the inductance of spiral copper inductors. Inductance value and quality (Q)-factor of the spiral copper inductor increased to 1.58 μH and 40.2 at 30 MHz respectively when 50 wt% BaFe12O19 particles were added into PPO matrix for a composite system as an embedded magnetic core.

Traumatic brain injury (TBI) is a major public health concern with high rates of morbidity and mortality worldwide. Currently used medications, though effective, are also associated with several adverse effects. Development of effective neuroprotective agents with fewer side-effects would be of clinical value. Previous studies have shown that withaferin compounds have a potential neuroprotective effect in nervous system disorders. However, the effect of withaferin compounds, especially withaferin A (WFA), on traumatic brain injury is unclear. In the present study, both in vivo and in vitro models were used to assess whether WFA could exert a neuroprotective effect after TBI and were used to explore the associated mechanisms. The results showed that WFA significantly improved neurobehavioral function in a dose-dependent fashion and alleviated histological alteration of injury to tissues in TBI mice. In vitro models of TBI revealed that dose-dependent WFA treatment increased the viability of SH-SY5Y cells. In addition, WFA treatment could attenuate blood-brain barrier disruption and brain edema via suppressing apoptosis in endothelial cells. Furthermore, both our in vivo and in vitro results reveal that WFA treatment could significantly reduce levels of several neuroinflammation cytokines (IL-1β, IL-6, and TNF-α), which correlate with an overall reduction in microglial activation. These data suggest that the neuroprotection by WFA is, at least in part, related to regulation of microglial activation and inhibition of vascular endothelial cell apoptosis. Taken together, these findings support further investigation of WFA as a promising therapeutic agent for promoting functional recovery after traumatic brain injury.

Glutathione (GSH) has been studied for its neuroprotection value in several diseases, but the effect of GSH on intracerebral hemorrhage (ICH) is unclear. In this study, we examined the protective effects of GSH in an experimentally induced ICH model and investigated the relative mechanisms. Adult male C57BL/6j mice were randomized into Sham, ICH and GSH treatment groups. GSH was injected with the dose of 50, 100 or 200 mg/kg once per day for 3 days, starting immediately after operation. The results revealed a GSH-mediated improvement of neurological deficits score (NDS), motor and sensory functions impairment in a dose-dependent manner three days post ICH (p 0.01, GSH 200 vs ICH. Sham, n = 12; ICH, n = 9; GSH 50, n = 10; GSH 100, n = 10; GSH 200, n = 11) in addition to significantly reduced mortality rate (p = 0.2632, GSH 200 vs ICH. n = 12 per group) and damage volume (p 0.05, GSH 200 vs ICH. n = 12 per group). GSH treatment also attenuated injury measured by decreased brain edema (p 0.05, GSH 200 vs ICH. Sham, n = 10; ICH, n = 10; GSH 200, n = 12), blood-brain barrier disruption (p 0.05, GSH 200 vs ICH. Sham, n = 10; ICH, n = 10; GSH 200, n = 12), and histopathological damage (p 0.05, GSH 200 vs ICH. Sham, n = 6; ICH, n = 6; GSH 200, n = 8) 72 h after ICH. In addition, GSH treatment also decreased cell apoptosis (p 0.01, GSH 200 vs ICH. Sham, n = 6; ICH, n = 6; GSH 200, n = 8) and resulted in up-regulated protein expression of complex I (p 0.01, GSH 200 vs ICH. Sham, n = 6; ICH, n = 6; GSH 200, n = 8), which was consistent with an overall up-regulation of complex I function in mitochondria using Oxygraph-2 K high resolution respirometry (p 0.05, GSH 200 vs ICH. Sham, n = 4; ICH, n = 5; GSH 200, n = 6). In conclusion, GSH effectively improved the prognosis of ICH mice by attenuating neurological impairment, decreasing neural damage, and inhibiting apoptosis. The neuroprotection by GSH resulted from the up-regulation of mitochondrial oxidative respiration function. The results of our study suggest that GSH can be a potential therapeutic agent for ICH.

Chloroplast NAD(P)H dehydrogenase-like complex (NDH) plays a crucial role in the protection of plants against oxidative stress. In higher plants, NDH interacts with Photosystem I (PSI) to form an NDH-PSI supercomplex. However, the chloroplast supercomplex with NADPH oxidation activity remains to be identified. Here, we reported the identification of a supercomplex of NDH with NADPH-nitroblue tetrazolium oxidoreductase activity in the chloroplast of rice panicle. The active supercomplex from the panicle chloroplast contained higher amounts of the NDH subunits (NdhH, NdhK, and NdhA) than that from the flag leaf chloroplast. The highly active supercomplex might underlie the high activity of the NADPH-dependent NDH pathway and the larger proton gradient across thylakoid membranes via cyclic electron flow around PSI, as well as the higher maximal photochemical efficiency of Photosystem II at the flowering to grain-filling stage. The supercomplex is suggested to be essential for the high efficiency of photosynthesis and play a protective role in the grain formation in rice plant.

The effect of replacing fish meal with raw and various processed soybeans meal on growth and protein metabolism of common carp Cyprinus carpio was evaluated in an 8-week trial. The common carp fingerlings[initial body weight(5.89±0.36) g] were fed five isonitrogenous and isocaloric feeds(30% digestible protein and 15 MJ/kg digestible energy) containing SBM replacing 50% of the fish meal protein,such as raw soybean(RSB),processed soybean by chemical inactivator,processed soybean by heating,processed soybean by heat alcohol,respectively. Results showed that weight gain of control were significantly different(P0.05),but those fed RSB were significantly lower than control(P0.05),those fed processed soybeans by chemical inactivator and by heating and by heat alcohol had no significant difference,but all significantly higher than control. Protease specific activity of control in the intestine and hepatopancreas was significantly higher than those fed RSB and processed soybeans by heat alcohol,but both had no significant difference with those fed processed soybeans by chemical inactivator and by heating(P0.05). RNA of 100% fish meal and 50% processed soybean by heating in white muscle were no significant difference(P0.05),but both were significantly higher than those fed RSB and processed soybeans by heat alcohol and by chemical inactivator and by heating,RNA/DNA of 100% fish meal and 50% processed soybean by heating and by chemical inactivator in white muscle had no significant difference(P0.05),but all were higher than those fed raw soybean(RSB) and processed soybean by heat alcohol(P0.05). RNA in white muscle and serum IGF-I had a positive correlation with growth(P0.05).The degree of negative effect of soybean anti-nutritional factors on fish is anti-trypsin inhibitoragglutininsoybean antigen protein under the experimental conditions,and proper control could reduce the negative impact of soybean anti-nutritional factors on fish.

The powder and extracts of Psoralea corylifolia L. were tested in lard at 100 °C by using the oxidative stability instrument (OSI) and were found to have strong antioxidant effects. Six compounds, bakuchiol, psoralen, isopsoralen, corylifolin, corylin and psoralidin were isolated from the herb and identified by UV, IR, Mass, 1 H and 13 C NMR spectra and melting point. Their antioxidant activities were investigated individually and compared with butylated hydroxytoluene (BHT) and α-tocopherol by the OSI at 100 °C. The results showed that bakuchiol, corylifolin, corylin and psoralidin had strong antioxidant activities, and especially psoralidin (stronger antioxidant property than BHT), but psoralen and isopsoralen had no antioxidant activities at 0.02% and 0.04% levels. The antioxidant activities of the compounds decrease in the following order: Psoralidin > BHT > α-tocopherol > bakuchiol > corylifolin > corylin > isopsoralen ∼ psoralen.

Novel iron carbide and potassium-promoted iron carbide catalysts were prepared and investigated for CO hydrogenation. The iron carbide showed high activity for CO hydrogenation under high pressures; with the addition of potassium, activity and selectivity to C5+ hydrocarbons were greatly enhanced, and the selectivity to methane was suppressed under high pressure.

This paper introduced a new Nanometer-Tin lubricating additive. Through the friction testing on an improved testing machine, the Nanometer additive with different contents used in Steel-Copper Tribo-pair has been investigated by analyzing the surface elements with AES and measuring the thickness and element distribution of the coating with SEM. The result shows that the weight of copper sample has obviously increased, and the ultra-thick friction coating (10μm−20μm), has formed on the surface of the copper sample. The experiment proved that the high concentrated Sn coating has good frictional properties. Therefore, the researching results possess significance to self-repair in wearing for mechanical system.