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Because of wake instability, bubbles always ascend along an unstable path, which is not considered when simulating their movement in steel refining and continuous casting systems. Utilizing the 3D shadow image method, a quantitative characterization of the bubble trajectories is conducted to establish a bubble path oscillation model considering the zigzag lateral movement of bubbles due to asymmetric wake shedding. This model is incorporated into a rectilinear bubble motion model within the Lagrangian framework and then used to simulate the free ascent of single bubbles within the 2.15–2.55 mm range. The predicted bubble ascent velocities and trajectories agree well with the experimental. The spatial position, velocity, acceleration, forces, volume swept by bubbles, and bubble residence time are discussed. The results shown that the dominant force in the horizontal direction is the lateral force, followed by the drag and virtual mass force. Compared to the rectilinear path model, the volume swept by bubbles with initial diameters of 2.15, 2.25, 2.34, 2.45, and 2.55 mm in this model increases by 30.8%, 32.0%, 34.0%, 31.5%, and 29.6%, respectively. These findings help accurately predict the path of bubbles and also may contribute to a better understanding of bubble dynamics in bubble metallurgy and clean steel production. [ABSTRACT FROM AUTHOR]

The precision in controlling fluid flow is crucial for the efficiency of microchannel devices. Consequently, it is essential to monitor the fluid within microchannels in real time. However, the microchannel flow's susceptibility to disturbance and small size present challenges in sensing. A Liquid‐Solid Triboelectric Nanogenerator (TENG) with grating electrodes is proposed for non‐invasive sensing of liquid plug movements in microchannels and is suitable for use with opaque channels. This sensor operates on the principle of initiating multiple pulse signals via grating electrodes. And analyze the motion of the liquid plug by the time difference between the signal peaks. It facilitates the measurement of liquid plug count, average speed, average acceleration, and the detection of flow direction. The liquid plug counters, and flow direction sensors yielded clear and distinguishable signals. The liquid plug average speed sensor achieves a 95% accuracy rate, and the acceleration sensor accurately distinguishes speed trends of the liquid plug with more than 85% precision. Grating electrodes are effectively employed for motion sensing. Analyzing the motion of an object by the time difference between voltage peaks offers greater stability than voltage magnitude analysis. Four portable prototypes are designed to make them applicable for fluid sensing in microchannel devices. [ABSTRACT FROM AUTHOR]

Buckling of the longitudinal rebar is one of the main forms of plastic hinge failure in reinforced concrete (RC) columns after an earthquake. This rebar buckling significantly impacts the seismic bearing capacity and energy dissipation capacity. To restrain the development of longitudinal rebar buckling behavior and delay the degradation of lateral strength in RC columns, this paper developed a new type of buckling restraint rebar (BRR) consisting of three components: longitudinal rebar, a restraint sleeve, and foam material. First, the BRR mechanical properties under compression and tension‐compression cyclic loading were obtained through quasi‐static loading tests. Then, the BRR compression and tension‐compression cyclic loading processes were numerically simulated based on ABAQUS finite element software. The simulated results were compared with the test results. Finally, a stress–strain constitutive model for this new BRR was proposed based on this study. Results showed that the restraint sleeve could significantly enhance the lateral stiffness and the bearing capacity of longitudinal reinforcement after yielding. The compressive performance of BRR was mainly affected by the length and wall thickness of the sleeve. The cyclic performance was mainly affected by the length of the sleeve and the clearance between the sleeve and the reinforcement. The BRR constitutive model proposed in this paper can accurately reflect the influence of restraint sleeves on the stiffness of longitudinal reinforcement after yielding. [ABSTRACT FROM AUTHOR]

Background: Glioblastoma (GBM) is a type of highly malignant brain tumor that is known for its significant intratumoral heterogeneity, meaning that there can be a high degree of variability within the tumor tissue. Despite the identification of several subtypes of GBM in recent years, there remains to explore a classification based on genes related to proliferation and growth. Methods: The growth-related genes of GBM were identified by CRISPR-Cas9 and univariate Cox regression analysis. The expression of these genes in the Cancer Genome Atlas cohort (TCGA) was used to construct growth-related genes subtypes (GGSs) via consensus clustering. Validation of this subtyping was performed using the nearest template prediction (NTP) algorithm in two independent Gene Expression Omnibus (GEO) cohorts and the ZZ cohort. Additionally, copy number variations, biological functions, and potential drugs were analyzed for each of the different subtypes separately. Results: Our research established multicenter-validated GGSs. GGS1 exhibits the poorest prognosis, with the highest frequency of chr 7 gain & chr 10 loss, and the lowest frequency of chr 19 & 20 co-gain. Additionally, GGS1 displays the highest expression of EGFR. Furthermore, it is significantly enriched in metabolic, stemness, proliferation, and signaling pathways. Besides we showed that Foretinib may be a potential therapeutic agent for GGS1, the worst prognostic subtype, through data screening and in vitro experiments. GGS2 has a moderate prognosis, with a slightly higher proportion of chr 7 gain & chr 10 loss, and the highest proportion of chr 19 & 20 co-gain. The prognosis of GGS3 is the best, with the least chr 7 gain & 10 loss and EGFR expression. Conclusions: These results enhance our understanding of the heterogeneity of GBM and offer insights for stratified management and precise treatment of GBM patients. [ABSTRACT FROM AUTHOR]

The application of the compressible layer in linings provides a feasible and safe solution to addressing the problems of the excessive deformations of surrounding rocks and support failure in the deep soft-rock tunnels. However, there still has not been a well-constructed method to report the mechanical responses of the tunnels supported by such a support system. The objective of this study is to provide an analytical approach to estimating the influence of the compressible layer on the tunnel performance. The mechanical model of the tunnel supported by the compressible layer and concrete lining within the viscoelastic–plastic geomaterial was established. The corresponding analytical solutions for the tunnel displacement and lining pressure are provided, where the influences of the stress path, tunnel face advancement, and installation delay of supports are considered. The effectiveness and reliability of the proposed model are validated by using the numerical calculation, and a good agreement between the analytical and numerical results are obtained. Finally, a comprehensive parametric investigation is carried out, including the influences of the yielding stress, yielding length and elastic modulus of the compressible layer and the lining installation time. The important findings are provided and several useful recommendations are proposed for the design of this supporting system. [ABSTRACT FROM AUTHOR]

The aggregation of alpha-synuclein (α-Syn) is closely related to the occurrence of some neurodegenerative diseases such as Parkinson's disease. The misfolding of α-Syn monomer plays a key role in the formation of aggregates and extension of fibril. However, the misfolding mechanism of α-Syn remains elusive. Here, three different α-Syn fibrils (isolated from a diseased human brain, generated by in vitro cofactor-tau induction, and obtained by in vitro cofactor-free induction) were selected for the study. The misfolding mechanisms of α-Syn were uncovered by studying the dissociation of the boundary chains based on the conventional molecular dynamics (MD) and Steered MD simulations. The results showed that the dissociation paths of the boundary chains in the three systems were different. According to the reverse process of dissociation, we concluded that in the human brain system, the binding of the monomer and template starts from the C-terminal and gradually misfolds toward the N-terminal. In the cofactor-tau system, the monomer binding starts from residues 58–66 (contain β3), followed by the C-terminal coil (residues 67–79). Then, the N-terminal coil (residues 36–41) and residues 50–57 (contain β2) bind to the template, followed by residues 42–49 (contain β1). In the cofactor-free system, two misfolding paths were found. One is that the monomer binds to the N/C-terminal (β1/β6) and then binds to the remaining residues. The other one is that the monomer binds sequentially from the C- to N-terminal, similar to the human brain system. Furthermore, in the human brain and cofactor-tau systems, electrostatic interactions (especially from residues 58–66) are the main driving force during the misfolding process, whereas in the cofactor-free system, the contributions of electrostatic and van der Waals interactions are comparable. These results may provide a deeper understanding for the misfolding and aggregation mechanism of α-Syn. [ABSTRACT FROM AUTHOR]

The increasing prominence of urban scaling laws highlights the importance of a systematic understanding of the variational scaling rates for different economic activities. In this article, we utilize several datasets to provide the first systematic investigation of the urban scaling of manufacturing industries in China. Most existing literature assumes that the divergence in urban scaling can be explained by returns to agglomeration, with a few exceptions instead highlighting the role of knowledge complexity or a mixture of both. Our main purpose in this paper is to explain the inter-sector variation of urban scaling rates. In doing this, we provide a clearer approach to demonstrating the relations between urban scaling, returns to agglomeration, and knowledge complexity. Our findings are twofold. First, after uncovering the scaling rates (denoted as urban concentration) and returns to agglomeration (denoted as urban productivity) for each sub-manufacturing sector, we prove that, rather than being a positive predictor, returns to agglomeration is slightly negatively associated with urban scaling rates. This finding reveals that urban concentration of manufacturing may not simply be a natural consequence driven by the maximization of performance. We also show that this result of the manufacturing system contrasts with what would be found in other pure knowledge systems such as patents. Secondly, we measure the complexity for each sector and demonstrate that the variation of urban concentration can be largely explained by their complexity, consistent with the knowledge complexity perspective. Specifically, complex manufacturing sectors are found to concentrate more in large cities than less complex sectors in China. This result provides support for the view that the growth of complex activities hinges more on diversity than on efficiency. The findings above can greatly reduce the current level of ambiguity associated with urban scaling, returns to agglomeration and complexity, and have important policy implications for urban planners, highlighting the significance of a more balanced and diversified configuration of urban productive activities for the growth of innovation economy. [ABSTRACT FROM AUTHOR]

To extend the lifetime, improve the power density and reduce the system cost, the film capacitor is applied to replace the large-volume electrolytic capacitor in motor drives. As the dc-link voltage fluctuates periodically, the rotor position estimation error and operation stability are necessary to be concerned in the position sensorless control methods. A cross-decoupling complex filtering-based position estimation method is investigated for the reduced capacitance interior permanent magnet synchronous motor drive system. Harmonic components of the extended back electromotive force (EEMF) caused by the dc-link voltage fluctuation are analyzed to evaluate the additional rotor position error. A cross-decoupling complex filter realized by the multiple first-order complex filters with different center frequencies is designed to improve the position estimation precision. Harmonics of the EEMF are suppressed and the position error can be eliminated. The estimation precision and operation ability are improved. Experimental results are performed to verify the effectiveness of the proposed method. [ABSTRACT FROM AUTHOR]

Corynebacterium glutamicum is regarded as an industrially important microbial cell factory and is widely used to produce various value-added chemicals. Because of the importance of C. glutamicum applications, current research is increasingly focusing on developing C. glutamicum synthetic biology platforms. Because of its ability to condense with adipic acid to synthesize the industrial plastic nylon-46, putrescine is an important platform compound of industrial interest. Developing a high-throughput putrescine biosensor can aid in accelerating the design–build–test cycle of cell factories (production strains) to achieve high putrescine-generating strain production in C. glutamicum. This study developed a putrescine-specific biosensor (pSenPuuR) in C. glutamicum using Escherichia coli-derived transcriptional factor PuuR. The response characteristics of the biosensor to putrescine were further improved by optimizing the genetic components of pSenPuuR, such as the response promoter, reporter protein, and promoter for controlling PuuR expression. According to the findings of the study, pSenPuuR has the potential to be used to assess putrescine production in C. glutamicum and is suitable for high-throughput genetic variant screening. [ABSTRACT FROM AUTHOR]

• The influence of friction slip contact between surrounding rock and concrete lining is investigated. • Time-dependent solution in closed form for tunnel mechanical response is provided. • A comprehensive parametric investigation on the influence of parameters involved is conducted. For a deep-buried tunnel in soft ground, the contact condition between the surrounding rock and lining significantly affects the mechanical response. This is because the slip bond relationship on the contact surface has a direct influence on the tangential slip, resulting in the redistribution of displacement and stress on the contact surface between the surrounding rock and lining. However, previous studies have not paid sufficient attention to this problem, and a well-established method for quantitatively evaluating this influence remains unavailable. Therefore, the influence of the contact behavior between the surrounding rock and lining was examined in this study using an analytical method. First, the concept of friction slip contact and corresponding theoretical equations are proposed based on the real contact behavior between the surrounding rock and lining. Second, considering the friction slip contact between the surrounding rock and lining, a mechanical model of the tunnel excavation-support process was established, and analytical solutions for the stress and displacement of the tunnel within a viscoelastic rock material were realized. Third, the effectiveness and reliability of the proposed solutions were validated. The results could be degenerated to those that do not consider the influence of the mechanical behavior of the contact surface. In addition, there was good agreement between the analytical results and further numerical calculation results. Finally, a comprehensive parametric investigation was conducted, including the influences of the initial release coefficient, friction coefficient, and installation time of the lining. Some useful recommendations for tunnel lining design are provided herein. [ABSTRACT FROM AUTHOR]

Bovine mastitis is among the most serious disease in the dairy industry and brings huge economic losses due to the decrease in milk quality and quantity. Betaine, a naturally occurring compound, possesses several pharmacological activities including anti-inflammatory and anti-oxidant ability, but whether betaine has protective effects on bovine mastitis is unknown. The aim of this study is to investigate the effect of betaine on mastitis and further discover its feasible molecular mechanism in lipopolysaccharide (LPS)-stimulated bovine mammary epithelial cells (BMECs). BMECs were pre-treated with or without betaine or LPS. Cell viability was measured with CCK-8 to examine the cytotoxicity. The levels of pro-inflammatory cytokines were measured by ELISA kits. Western blotting was used to explore the regulation of genes associated with inflammatory and oxidative stress genes. The results showed that LPS treatment significantly increased the production of pro-inflammation (IL-1β, IL-6 and TNFα), enhanced malondialdehyde (MDA) content, reduced superoxide dismutase (SOD) and glutathione peroxidase (GSH-Px) activity, and markedly up-regulated the protein expression of COX2 and iNOS (p < 0.05). However, betaine pre-treatment remarkably restored the above phenomenon compared with the LPS group. Additionally, we also observed that betaine exposure significantly restricted LPS-induced the phosphorylation of IκB and NF-κB p65 (p < 0.05). Moreover, pre-treatment of BMECs with betaine abolished LPS-induced the increase of Nrf2 and HO-1 protein levels (p < 0.05). These results confirm that betaine can alleviate LPS-induced inflammatory response and oxidative damage by modulating NF-κB and Nrf2 signalling pathways. Betaine alleviated the production of pro-inflammation cytokines (IL-1β, IL-6 and TNFα) in BMECs after LPS stimulation. Betaine restored LPS-elicited nuclear factor kappa-B (NF-κB) signalling pathway activity. Betaine recovered LPS-induced the activity of SOD and GSH-Px and MDA content. Betaine inhibited the increase of protein expression of Nrf2 and HO-1 challenged with LPS. [ABSTRACT FROM AUTHOR]

The power density can be improved and the system cost can be saved in the reduced dc-link capacitance motor drive system. The line inductance can also be diminished to reduce the system volume further. In previous research works, the active damping control methods mainly concentrated on the drive system equipped with a larger line inductor. In this article, a dc-link voltage estimation feedback-based active damping method is proposed to suppress the grid current harmonics and improve the drive system stability with low line inductance. The dc-link voltage ripple caused by the LC resonance is analyzed to evaluate the direct dc-link voltage feedback-based active damping control method. To improve the damping performance, the resonant component of the dc-link voltage caused by the LC resonance could be obtained through the grid current to establish the feedback control loop. The sampling delay should be compensated to improve the control performance. The stability of the drive system is evaluated by the Nyquist plots of the impedance model, and the grid current is also analyzed, which could satisfy the harmonic requirements of IEC-61000-3-2. Experimental results are performed to verify the effectiveness of the proposed method. [ABSTRACT FROM AUTHOR]

A flexible support system provides a most potential solution to the challenge of support failure caused by large deformation of surrounding rock in deep soft rock tunnels. This is behind on the concept that rock pressure can be decreased to a low level by allowing rock deformation. However, a well-established method for the flexible support system is still unavailable. This study aims to provide a quick and easy prediction of the mechanical response of a "flexible support system" supported tunnel based on the analytical method. First, the mechanical behaviors of flexible rockbolts and ductile linings are introduced, and then the interaction model between surrounding rock and flexible support system is established. Furthermore, time-dependent solutions in closed form for the displacement and stress around the tunnel are obtained, where the influences of tunnel face advancement and installation delay of flexible support system are considered. The effectiveness and reliability of the proposed solutions are validated by a subsequent case study and numerical simulation, and a good agreement is achieved among analytical solutions, comparing with numerical results and monitoring data. Finally, a comprehensive parametric investigation is performed based on the proposed solutions, including the installation time and yielding stress of flexible rockbolts, installation time of ductile lining and yielding stress and yielding displacement of highly deformable elements. Some recommendations for the design of flexible support system are provided. [ABSTRACT FROM AUTHOR]

The present study aimed to examine the effects of short-term exposure to ammonia on stress and oxidative responses in shrimp (Litopenaeus vannamei) and to determine whether the antioxidant system related to the regulatory role of transcription factors and stress proteins was activated. Shrimp were exposed ammonia-N at four concentrations: 0 (control), 5, 10, and 15 mg/L, for 48 h. The hepatopancreas was sampled to measure the levels of glutathione (GSH), malondialdehyde (MDA), nitric oxide (NO); the activities of superoxide dismutase (SOD), catalase (CAT), nitric oxide synthase (NOS); and the expression levels of GSH-px (encoding glutathione peroxidase), GST (encoding glutathione-S-transferase), HSP70 (encoding heat shock protein 70), HSP90 (encoding heat shock protein 90), p53 , RELISH , and AKIRIN. We observed that exposure to a high ammonia content increased the abundance of oxidative factors (MDA, CAT, SOD, NOS, and NO), reduced the levels of GSH, and upregulated the mRNA expression levels of antioxidant genes (GSH-px and GST), stress-related genes (HSP70 and HSP90), and transcription factor genes (p53 , RELISH , and AKIRIN). These results indicated that ammonia induced oxidative stress and inflammation. Both enzymatic and nonenzymatic antioxidant defense systems are involved, which might be regulated by HSPs, as well as certain transcription factors, such as p53 and nuclear factor kappa B (NF-κB), thus mounting an adaptive response to help rebalance redox homoeostasis. • Ammonia stress in shrimp increased oxidative and inflammatory parameters. • Ammonia stress increased the expression of antioxidant and stress-related genes. • Oxidation/inflammation-related transcription factor expression help to rebalance redox homoeostasis under ammonia stress. [ABSTRACT FROM AUTHOR]

• A coupling control method of superheat and nitrogen oxides is proposed to control GEHP system. • The superheat regulation time is less than 400 s and the stability is good under the coupling control. • The fluctuation of the unit outlet temperature is less than 0.5 °C under variable load conditions. • The primary energy ratio of GEHP can reach 1.59 under coupling control and the NO x emission is less than 100 ppm. • The coupling control strategy achieve excellent performance and emission characteristic. Gas engine heat pump (GEHP) is gradually developing due to the high energy efficiency. However, the gas engine is easily disturbed by load fluctuation, which affects the stability of GEHP operation and causes higher nitrogen oxides (NO x) emission concentrations. Therefore, an efficient control method is necessary to ensure system stability, improve energy efficiency and reduce NO x emissions. In this paper, a coupling control strategy of superheat and NO x is proposed. The results show that the superheat can maintain stability with the small overshoot and adjustment time of less than 400 s when the engine speed changes. When the superheat setting value changed continuously, the superheat overshoot and error are less than 0.5 °C and the adjustment time is about 100 s. Meanwhile, the system outlet temperature is stable, the overshoot is less than 1 °C. The amplitude variation of the refrigerating capacity is similar to the amplitude variation of the superheat. The variation range of total heat capacity is greater than that of refrigerating capacity. In addition, the performance and emission of the GEHP are respectively studied when the superheat is 4 °C and 7 °C, at the optimum excess air coefficient. The NO x emissions are always below 100 ppm, but the primary energy ratio (PER) is higher under the superheat of 4 °C. Therefore, the proposed coupling control strategy can achieve good stability, excellent performance and emission characteristics. [ABSTRACT FROM AUTHOR]

Problem: Diminished ovarian reserve (DOR) is a daunting obstacle in in vitro fertilization (IVF) or intra cytoplasmic sperm injection (ICSI), leading to poor reproductive outcomes. We aim to characterize the T cell and cytokine profiles in follicular fluid (FF) and elucidate its contribution to the development of DOR. Method of study: A total of 92 infertile women were enrolled in the study. We assessed the ultrastructure, proliferation, and apoptosis of granulosa cells (GCs). The levels of CCL5 and cytokines in FF was measured. Additionally, we classified the T cells and analyzed cytokines production in T cell. We further verified whether CCL5 can recruit specific T cell subcytes to the follicles. Results: Cytoplasmic vacuolization, nucleolar dissociation, partial shortening, swelling, and fusion of mitochondrial cristae were obvious in GCs with DOR. The proliferation of GCs decreased and the proportion of apoptosis increased in DOR. The down‐regulation of Bcl‐2 and up‐regulation of caspase3 were seen in GCs with DOR. The number of CD8+ T cells and proportion of CD8+ /CD4+ T cells in DOR exceeded the control. Higher positive percentage of CD69, CCR5, and IFN‐γ in CD8+ T cells, lower positive percentage of IL‐10 in CD4+ T cells and PD‐1 in CD8+ T cells were detected in DOR. CCL5 accumulated promoting the recruitment of CD8+ T cells to the follicles on interaction with CCR5. Conclusion: The abnormal proportion of CD8+ T cells and elevated CCL5 and IFN‐γ may change the immune balance in FF and impair the growth of GCs, which in turn fuel the progression of DOR. [ABSTRACT FROM AUTHOR]

Purpose: Sirtuin 2 (SIRT2) is functionally important in cancer progression and treatment resistance as an NAD+-dependent deacetylase, whereas its role in endometrial cancer (EC) is limitedly investigated. This study aimed to evaluate the regulatory role of SIRT2 on cell stemness and chemosensitivity in EC. Methods: SIRT2 expression was detected in human EC cell lines, including Ishikawa, AN3CA, HEC1A, KLE, and normal human endometrial (uterine) epithelial cells (served as controls). Then, SIRT2 overexpression plasmids (constructed with pcDNA3.1 vector) and knock-down plasmids (constructed with pGPH1 vector) were transfected in Ishikawa cells and KLE cells, respectively to assess the influence of SIRT2 on EC cell stemness and chemosensitivity to cisplatin and paclitaxel. Results: SIRT2 mRNA and protein were both overexpressed in EC cell lines (including Ishikawa cells, AN3CA cells, HEC1A cells, and KLE cells) compared with controls. Upregulation of SIRT2 increased the sphere formation capacity (by sphere formation assay and extreme limiting dilution analysis) and CD133+ cells rate in Ishikawa cells, whereas knock-down of SIRT2 reduced the sphere formation capacity and CD133+ cells rate in KLE cells. As for chemosensitivity, upregulation of SIRT2 increased relative cell viability in cisplatin-treated and paclitaxel-treated Ishikawa cells. In contrast, SIRT2 knock-down suppressed relative cell viability in cisplatin-treated but not in paclitaxel-treated KLE cells. In addition, SIRT2 overexpression increased, while SIRT2 knock-down reduced p-MEK and p-ERK1/2 levels in EC cells. Conclusion: SIRT2 promotes cell stemness and activates the MEK/ERK signaling pathway while represses chemosensitivity in EC. [ABSTRACT FROM AUTHOR]

Beat phenomenon is an important issue for the practical application of electrolytic capacitorless motor drives. In this study, the characteristics of stator current harmonics caused by the voltage sampling delay are analyzed. Further, the beat phenomenon generated from the interaction between the harmonics and the fundamental currents is investigated, and the envelope feature of the stator current is derived mathematically. For the purpose of suppressing the beat phenomenon, a voltage reconstruction strategy is proposed to reduce the influence of dc-link voltage sampling delay at the six times of grid frequency. By utilizing the reconstructed dc-link voltage for calculation of PWM duty ratio, the beat phenomenon can be attenuated significantly. The proposed method can be integrated into motor control system easily. Experimental results show the effectiveness of the proposed strategy in a prototype of electrolytic capacitorless permanent magnet synchronous motor drive. [ABSTRACT FROM AUTHOR]

• Shaft vibration and pressure fluctuation are measured in a gas-liquid mixed-flow pump. • Multifractal characteristics are compared and analysed for different IGVFs. • Surge prediction is realized based on based on multifractal detrended fluctuation analysis. Surge causes a sudden drop in pressure increase and possibly results in severe vibration in a multiphase pump once inlet gas volume fraction (IGVF) exceeds a critical value. In this study, a synchronous test system including a high-speed camera, a laser Doppler vibrometer and high-frequency pressure fluctuation sensors is constructed to measure shaft vibration and pressure fluctuation in a gas–liquid mixed-flow pump at different IGVFs. The multifractal characteristics of the collected signals obtained by using the multifractal detrended fluctuation analysis method have been analysed and compared in detail. Results show that pressure surge occurs once the flow pattern transforms from bubbly flow to gas pocket flow in the pump. The multifractal characteristics of the vibration and pressure fluctuations depend strongly on the IGVF. Before the surge, the multifractal strength of vibration and pressure fluctuation increase with the increment of IGVF. After the surge, they decrease rapidly as the bubble coalescence into a mass of gas pockets. Furthermore, the local fluctuation of the vibration is insensitive to the variation of the IGVF and the multifractal spectrum has a right tail at each IGVF. The local fluctuation of the pressure fluctuation become severe with the coalescence of bubbles and the multifractal spectrum has a left tail after the surge. The incipient surge state can be effectively predicted by characteristics parameters extracted from the multifractal spectrum of the shaft vibration and the pressure fluctuation in the pump. This study provides an effective method for surge state prediction in multiphase pumps. [ABSTRACT FROM AUTHOR]

Organophosphate triesters (tri-OPEs) threaten human health through dietary exposure, but little is known about their feed-to-food transfer and in vivo behavior in farm animals. Herein 135 laying hens were fed with contaminated feed (control group, low-level group and high-level group) to elucidate the bioaccumulation, distribution, and metabolism of the six most commonly reported tri-OPEs. The storage (breast muscle), metabolism and mobilization (liver and blood) and non-invasive (feather) tissues were collected. The exposure-increase (D1∼14) and depuration-decrease (D15∼42) trends indicated that feed exposure caused tri-OPE accumulation in animal tissues. Tissue-specific and moiety-specific behavior was observed for tri-OPEs. The highest transfer factor (TF) and transfer rate (TR) were observed in liver (TF : 14.8%∼82.3%; TR : 4.40%∼24.5%), followed by feather, breast muscle, and blood. Tris(2-chloroisopropyl) phosphate (TCIPP) had the longest half-life in feather (72.2 days), while triphenyl phosphate (TPhP) showed the shortest half-life in liver (0.41 days). Tri-OPEs' major metabolites (organophosphate diesters, di-OPEs) were simultaneously studied, which exhibited dose-dependent and time-dependent variations following administration. In breast muscle, the inclusion of di-OPEs resulted in TF increases of 735%, 1108%, 798%, and 286% than considering TCIPP, tributyl phosphate, tris(2-butoxyethyl) phosphate and tris(2-ethylhexyl) phosphate alone. Feather was more of a proxy of birds' long-term exposure to tri-OPEs, while short-term exposure was better reflected by di-OPEs. Both experimental and in silico modeling methods validated aryl-functional group facilitated the initial accumulation and metabolism of TPhP in the avian liver compared to other moiety-substituted tri-OPEs. [Display omitted] • The in vivo transfer of tri-OPEs from feed to laying hens' tissues were studied. • Exposure-increase and depuration-decrease were observed during 42-days. • Involving metabolites significantly increased tri-OPE body burden in farm animals. • Tissue-specific and moiety-specific behavior were observed for tri-OPEs. • In vivo behavior were revealed by experimental and in silico modeling methods. [ABSTRACT FROM AUTHOR]

Electrical fields (EFs)-assisted in-situ bioremediation of petroleum-contaminated groundwater, such as polycyclic aromatic hydrocarbons, has drawn increasing attention. However, the long-term stability, the EFs influence, and metabolic pathways are still poorly understood, hindering the further development of robust technology design. Herein, a series of EFs was applied to the phenanthrene-contaminated groundwater, and the corresponding system performance was investigated. The highest removal capacity of phenanthrene (phe) (7.63 g/(m3·d)) was achieved with EF_0.8 V biofilm at a hydrolytic retention time of 0.5 d. All the biofilms with four EFs exhibited a high removal efficiency of phe over 80% during a 100-d continuous-flow operation. Intermediates analysis revealed the main pathways of phe degradation: phthalate and salicylate via hydroxylation, methylation, carboxylation, and ring cleavage steps. Synergistic effects between phe-degraders (Dechloromonas), fermentative bacteria (Delftia), and electroactive microorganisms (Geobacter) were the main contributors to the complete phe mineralization. Genes encoding various proteins of methyl-accepting (mcp), response regulator (cheABDRY), and type IV pilus (pilABCMQV) were dominant, revealing the importance of cell motility and extracellular electron transfer. Metagenomics analysis unveiled phe-degrading genes, including ring reduction enzymes (bamBCDE), carboxylase of aromatics (ubiD), and methyltransferase protein (ubiE , pcm). These findings offered a molecular understanding of refractory organics' decompositions in EFs-governed biotechnology. [Display omitted] ● Electrical field-governed biofilms (0.3-1.8 V) kept stable removal efficiency of PHE. ● Highest removal capacity of PHE (7.63 g/(m3·d)) was realized with EF_0.8 V biofilm. ● The phe degradation mainly underwent phthalate and salicylate pathways. ● Mutualism between phe-degraders, fermentative, and EAMs enhanced phe mineralization. ● EF_0.8 upregulated genes encoding EET, methanogenesis, and carboxylase genes. [ABSTRACT FROM AUTHOR]

Cavitation can lead to reduced efficiency, increased vibration and noise in hydraulic turbines. Accurate and rapid identification of cavitation states in a turbine is important. In this work, a test system has been constructed for a hydraulic bulb turbine, to synchronously obtain cavitation images on runner blades, vibrations on both the runner hub and the runner chamber, and pressure fluctuations on the draft tube of the turbine at different cavitation conditions. The multifractal characteristics of the collected signals obtained by using the multifractal detrended fluctuation analysis method have been analysed and compared in detail. It is found that the multifractal characteristics of the vibrations and pressure fluctuations depend strongly on the cavitation state. The multifractal strength of the pressure fluctuations in the draft tube is stronger than that of the vibrations on the runner, induced by cavitation. Furthermore, some multifractal parameters of vibrations and pressure fluctuations have been extracted and used for cavitation state identification in the turbine, which is important for safe operation of a turbine. [ABSTRACT FROM AUTHOR]

In the voltage source inverter applications, inverter nonlinearities would affect the parameter identification process in many ways. Hence, this article proposes an offline identification method for resistance and dq-axis inductance surface by considering the inverter nonlinearity characteristics. A variable amplitude square-wave injection (VASI) scheme is proposed for the dq-axis inductance identification. The VASI method achieves the inductance identification with a novel data sampling strategy. Meanwhile, it can also establish the inductance surfaces by only a few identified data points with a polynomial fitting algorithm, which greatly reduces the identification time compared with the existing methods. The resistance identification is realized by a slope signal injection method, in which the effect of IGBT voltage drop is analyzed. In order to improve the identification accuracy, the inverter nonlinearities are compensated by a self-learning method considering the zero-axis voltage at different rotor positions. At the same time, the sampling error in zero current zones of abc-phases is researched. In order to verify the effectiveness and generality, the proposed method is carried out on two different test machines and confirmed by finite element analysis. [ABSTRACT FROM AUTHOR]

Suspended sediment load (SSL) estimation is essential for both short- and long-term water resources management. Suspended sediments are taken into account as an important factor of the service life of hydraulic structures such as dams. The aim of this research is to estimat SSL by coupling intrinsic time-scale decomposition (ITD) and two kinds of DDM, namely evolutionary polynomial regression (EPR) and model tree (MT) DDMs, at the Sarighamish and Varand Stations in Iran. Measured data based on their lag times are decomposed into several proper rotation components (PRCs) and a residual, which are then considered as inputs for the proposed model. Results indicate that the prediction accuracy of ITD-EPR is the best for both the Sarighamish (R2 = 0.92 and WI = 0.96) and Varand (R2 = 0.92 and WI = 0.93) Stations (WI is the Willmott index of agreement), while a standalone MT model performs poorly for these stations compared with other approaches (EPR, ITD-EPR and ITD-MT) although peak SSL values are approximately equal to those by ITD-EPR. Results of the proposed models are also compared with those of the sediment rating curve (SRC) method. The ITD-EPR predictions are remarkably superior to those by the SRC method with respect to several conventional performance evaluation metrics. [ABSTRACT FROM AUTHOR]

In order to extend the lifetime and save the system cost, the film capacitor is applied to the dc link of interior permanent magnet synchronous motor (IPMSM) drives. Many active damping control methods have been carried out to improve the drive system stability, which needs the accurate value of the dc-link film capacitor. In this letter, an online dc-link capacitance estimation method is investigated for reduced capacitance IPMSM drives, which do not need any additional signal injection or sensor. The power coupling characteristics are analyzed to obtain the instantaneous power of the dc-link capacitor from the inverter and the grid sides. The bandpass filter is applied to extract the dc-link voltage and capacitor power with twice the frequency of the grid voltage. The dc-link capacitance could be estimated by the fundamental component of the dc-link voltage. The proposed method can be used for different kinds of load types and motor types of the drive system. The experimental results are performed to verify the estimation method, and the estimation error is within 1%. [ABSTRACT FROM AUTHOR]

During deep excavation in weak rock masses, the time-dependent deformation of the rock and longitudinal advancement process have significant influences on the tunnel performance. Accordingly, a combined support system consisting of rockbolts and linings is commonly used in such tunnels to ensure their stability. However, there are no well-established solutions for quickly and accurately evaluating the safety of those support systems. To address this problem, mechanical model of a circular tunnel with a rockbolt–lining combined system is analytically built in this study. Then mathematical formulas for the stresses and displacements around the tunnel are derived, considering the time-dependent behaviors of the rocks and tunnel face advancement effect. Furthermore, the analytical formula proposed in this study is compared with existing solutions and numerical results obtained using the finite-element software Abaqus, and a good agreement is achieved. Finally, a parametric investigation is conducted regarding the influences on the tunnel's mechanical performance. The results show that the installation time (t0) and distribution density of rockbolts (SθSz) and the installation time of the lining (t1) have a significant influence on the deformation of the surrounding rock. Although the installation times of bolt and lining are positively related to the deformation suppression effect of the surrounding rock, they are negatively related to the stress of the bolt and lining. It is found that the closer the installation time of bolt and lining, the greater the stress of lining; otherwise, the greater the stress of bolts. Furthermore, the initial release coefficient (m) and the ratio of tunnel excavation rate to influence radius can influence the deformation rate of surrounding rock. Finally, the study proposes a new method for quickly evaluating the viscoelastic deformation of a tunnel. [ABSTRACT FROM AUTHOR]

Co3−xMnxO4 is a bimetal oxide with excellent electrochemical activity in alkaline solution, has been regarded as a promising alternative in the field of ion-air batteries and proton exchange membrane fuel cell (PEMFC). Herein, we report a simple solvothermal-calcination method to fabricate Co3−xMnxO4 with tunable external Co3+/Co2+ and Mn3+/Mn2+ ratio. The tunable ratio of element valence in the bimetal results in a higher exposure of active center for oxygen redox reaction (ORR), and thus lead to a better ORR activity, which was confirmed by X-ray photoelectron spectroscopy characterizations and electrochemical measurements. Specially, Co1.8Mn1.2O4 with a Co3+/Co2+ ratio of 2.08 showed an overpotential of 0.37 V at benchmark ORR current density of 3 mA/cm2 in 0.1 M KOH, which is lower than that of pure oxide (Mn3O4 0.53 V and Co3O4 0.56 V). In addition, the as prepared Co1.8Mn1.2O4 exhibited a positive half-wave potential (0.83 V vs RHE) due to their more active sites, promotes charge transfer, adsorption and desorption of oxygen species. This work provides a strategy for the design and fabrication of earth-abundant, low-cost electrocatalysts for PEMFC in practical applications. Co3−xMnxO4 was fabricated by tuning external Co3+/Co2+ and Mn3+/Mn2+ ratio, and the activity initially shows a positive correlation with the ration of Co3+/Co2+ in Co3−xMnxO4. [ABSTRACT FROM AUTHOR]

Corynebacterium glutamicum is an essential industrial strain that has been widely harnessed for the production of all kinds of value-added products. Efficient multiplex gene editing and large DNA fragment deletion are essential strategies for industrial biotechnological research. Cpf1 is a robust and simple genome editing tool for simultaneous editing of multiplex genes. However, no studies on effective multiplex gene editing and large DNA fragment deletion by the CRISPR/Cpf1 system in C. glutamicum have been reported. Here, we developed a multiplex gene editing method by optimizing the CRISPR/Cpf1-RecT system and a large chromosomal fragment deletion strategy using the CRISPR/Cpf1-RecET system in C. glutamicum ATCC 14067. The CRISPR/Cpf1-RecT system exhibited a precise editing efficiency of more than 91.6% with the PAM sequences TTTC, TTTG, GTTG or CTTC. The sites that could be edited were limited due to the PAM region and the 1–7 nt at the 5′ end of the protospacer region. Mutations in the PAM region increased the editing efficiency of the − 6 nt region from 0 to 96.7%. Using a crRNA array, two and three genes could be simultaneously edited in one step via the CRISPR/Cpf1-RecT system, and the efficiency of simultaneously editing two genes was 91.6%, but the efficiency of simultaneously editing three genes was below 10%. The editing efficiency for a deletion of 1 kb was 79.6%, and the editing efficiencies for 5- and 20 kb length DNA fragment deletions reached 91.3% and 36.4%, respectively, via the CRISPR/Cpf1-RecET system. This research provides an efficient and simple tool for C. glutamicum genome editing that can further accelerate metabolic engineering efforts and genome evolution. [ABSTRACT FROM AUTHOR]

Purpose: Excessive exposure of glucocorticoids activates adipose lipolysis, increases circulating free fatty acids, and contributes to ectopic lipid deposition in liver and skeletal muscle. Our previous study demonstrated that maternal betaine supplementation attenuates glucocorticoid-induced hepatic lipid accumulation in rat offspring. However, it is unclear whether maternal betaine supplementation is effective in preventing glucocorticoid-induced lipolysis in the adipose tissue of offspring. Methods: In this study, 20 pregnant rats were fed with basal or betaine-supplemented (10 g/kg) diets throughout gestation and lactation, and the offspring rats were raised on the basal diet from weaning till 3 months of age followed by daily intraperitoneal injection of saline or 0.1 mg/kg dexamethasone (DEX) for 3 weeks. Results: Chronic DEX treatment significantly (P < 0.05) decreased serum corticosterone level and increased proinflammatory cytokines, such as TNFα, IL-1β, and IL-6. Meanwhile, GR protein content in adipose tissue was increased in response to DEX treatment, which was associated with a significant (P < 0.05) up-regulation of ATGL and HSL expression at both mRNA and protein levels. All these DEX-induced changes were significantly (P < 0.05) attenuated in progeny rats derived from betaine-supplemented dams. Furthermore, DEX-induced hypomethylation of ATGL and HSL gene promoters was reversed by maternal betaine supplementation. Conclusions: Taken together, these results suggest that maternal betaine supplementation is effective in alleviating glucocorticoid-induced lipolysis in adipose tissue with modification of DNA methylation on the promoter of lipolytic genes. [ABSTRACT FROM AUTHOR]

Observational studies have shown that many natural systems need to remain in rhythmic oscillation activity. Yet, the appearance of oscillation quenching phenomena lead to the breakdown of intrinsic behavior of practical systems, often causing unpredictable results. To address the important problem about how to avoid or revive the paralyzed system, in this work, we use the mean-field function of the entire system as an external feedback acts on every unit. Taking the classical limit cycle of Stuart–Landau model as example, we find that oscillation quenching state can be eliminated effectively and thus revoke the deprived oscillation. Through extensive theoretical analyses and numerical simulations, the results show for various death scenarios that the oscillation quenching regions shrink drastically in the parameter space with increasing feedback strength. Our method can be regarded as a general framework to maintain or retrieve the continued oscillation for coupled nonlinear systems in diverse applications. [ABSTRACT FROM AUTHOR]

WRKY transcription factors play crucial roles in regulation mechanism leading to the adaption of plants to the complex environment. In this study, AhWRKY family was comprehensively analyzed using bioinformatic approaches in combination with transcriptome sequencing data of the drought-tolerant peanut variety 'L422'. A total of 158 AhWRKY genes were identified and named according to their distribution on the chromosomes. Based on the structural features and phylogenetic analysis of AhWRKY proteins, the AhWRKY family members were classified into three (3) groups, of which group II included five (5) subgroups. Results of structure and conserved motifs analysis for the AhWRKY genes confirmed the accuracy of the clustering analysis. In addition, 12 tandem and 136 segmental duplication genes were identified. The results indicated that segmental duplication events were the main driving force in the evolution of AhWRKY family. Collinearity analysis found that 32 gene pairs existed between Arachis hypogaea and two diploid wild ancestors (Arachis duranensis and Arachis ipaensis), which provided valuable clues for phylogenetic characteristics of AhWRKY family. Furthermore, 19 stress-related cis-acting elements were found in the promoter regions. During the study of gene expression level of AhWRKY family members in response to drought stress, 73 differentially expressed AhWRKY genes were obtained to have been influenced by drought stress. These results provide fundamental insights for further study of WRKY genes in peanut drought resistance. [ABSTRACT FROM AUTHOR]

BACKGROUND: We reported previously that maternal betaine promotes hepatic insulin‐like growth factor (IGF2) expression in F1 offspring rats through hypermethylation of the IGF2/H19 imprinting control region (ICR). It remains unknown whether this acquired trait can be transmitted to the F2 generation. This study aimed to determine whether dietary betaine supplementation to grand dams affects the hepatic IGF2 expression in F2 rat offspring and how it is related to alterations in DNA methylation. F2 rat offspring derived from grand dams fed basal or betaine‐supplemented diet (10 g kg−1) were examined at weaning. Serum IGF2 concentration was measured with enzyme‐linked immunosorbent assay (ELISA). Hepatic expression of IGF2, together with other proliferation and apoptosis markers, was determined by using quantitative polymerase chain reaction (qPCR), western blot, and immunohistochemistry. The methylation status of the IGF2/H19 ICR and the promoters of IGF2 gene were detected by methylated DNA immunoprecipitation quantitative polymerase chain reaction (MeDIP‐qPCR). RESULTS: The maternal betaine‐induced up‐regulation of hepatic IGF2 expression in F1 rat offspring was transmitted to the F2 generation. The F2 rats from the betaine group demonstrated enhanced hepatic IGF2 expression at both mRNA and protein levels, in association with higher serum IGF2 concentration. No alterations were observed in the ICR methylation of the IGF2/H19 locus, and hypomethylation was detected in promoters of IGF2 gene in betaine group. CONCLUSION: These results indicate that maternal betaine enhances hepatic IGF2 expression in F2 rat offspring through modification of DNA methylation on IGF2 promoters. © 2019 Society of Chemical Industry [ABSTRACT FROM AUTHOR]

• A chaotic mechanism was introduced to enhance bat optimization algorithm. • An inertial weight was set for the velocity to improve the ability of global exploration. • Extensive benchmark problems were used to verify the proposed method. In this paper, a chaos-enhanced bat algorithm is proposed to tackle the global optimization problems. Bat algorithm is a relatively new stochastic optimizer inspired by the echolocation behavior of bats in nature. Due to its effectiveness, it has been applied to many fields such as engineering design, feature selection, and machine learning. However, the classical approach is often prone to falling into local optima. This paper proposes an enhanced bat algorithm to alleviate this problem observed in the original algorithm. The proposed method controls the steps of chaotic mapping by a threshold and synchronizes the velocity of agents using a velocity inertia weight. These mechanisms are designed to boost the stability and convergence speed of the bat algorithm, instantly. Eighteen well-established and the state-of-the-art meta-heuristic approaches are considered to validate the effectiveness of the developed algorithm. Experimental results reveal that the proposed chaos-enhanced bat algorithm is not only superior to the well-established algorithms such as the original method but also the latest improved approaches. Also, the proposed method is successfully applied to I-beam design problems, welded beam design, and pressure vessel design. The results show that chaos-enhanced bat algorithm can deal with unconstrained and constrained feature spaces, effectively. [ABSTRACT FROM AUTHOR]

Beat phenomenon is an important concern in the reduced dc-link capacitance motor drive system. In previous research works, the topic is mainly concentrated on the beat phenomenon caused by the interaction of the fluctuated dc-link voltage and the motor phase voltage. In this paper, another form of the beat phenomenon generated by the fluctuated dc-link voltage and the severely fluctuated load torque is investigated. The effect of the beat phenomenon on the grid current and the motor speed is analyzed, which fluctuate with the low-frequency oscillation. In order to improve the drive system performance, a power balancing controller is proposed to suppress the grid current fluctuation, and a resonant controller is utilized to regulate the periodic power signals. Meanwhile, the applied fluctuated torque suppression method could improve the performance of the motor speed, which is only sensitive to the frequency of the fluctuated load torque. Experimental results are provided to verify the effectiveness of the proposed method. [ABSTRACT FROM AUTHOR]

The instability issue is an important concern in the reduced dc-link capacitance motor drive system, which is caused by the interaction of the LC resonance and the negative impedance of the constant power load (CPL). Harmonics of the grid current also need to be concerned to meet the requirement of the application standards. In this paper, the impedance model of the drive system is established considering the dc-link voltage fluctuation, which is applied to evaluate the drive system stability. The grid current harmonics issue could also be analyzed by the grid input impedance model. A novel grid current feedback based stabilization control method is proposed to stabilize the drive system, which could formulate the Nyquist plot of the drive system. Besides, the grid current harmonics could also be suppressed effectively by adopting the proposed stabilization control method. Experimental results are performed to verify the effectiveness of the proposed method. [ABSTRACT FROM AUTHOR]

As yielding supports can deform without being damaged, the yielding principle has attracted significant attention for tunnelling in squeezing ground compared with the heavy support method. The deformation energy of surrounding rock can be managed using yielding supports that maintain the rock pressure within the bearing capacity of the supports. However, although the yielding principle has been often applied in practical scenarios, a design method for yielding supports has yet not been well developed. This study discusses interaction between the squeezing ground and yielding supports and investigates the influence of the time‐dependent behaviour of rock on the yielding supports. The yielding supports can be implemented by the movement of sliding joints of steel arches or by shortening the yielding elements inserted in shotcrete linings. The deforming process of yielding supports can be divided into three stages: elastic a, yielding, and elastic b. A three‐stage pressure‐displacement relationship of yielding supports is proposed and a method is provided for the calculation of the support stiffnesses of yielding supports in different stages. Furthermore, a unified design approach for the yielding supports is presented and the theoretical model is established after simplifying the asymmetry of problem. The analytical solution for tunnel displacement and support pressure in a tunnel supported by the yielding supports is obtained. The proposed design method for the yielding supports is successfully applied to the Saint Martin La Porte access tunnel, and the mean tunnel deformation in this tunnel is appropriately predicted by the analytical solution. Additionally, a parametric investigation is performed based on the analytical solution, and the effects of yielding path, yielding displacement, support thickness, and installation time of the yielding supports are discussed. Finally, certain highlights of the analytical model of yielding supports in this study are identified, compared with other researches, and recommendations for the design of the yielding supports are provided. The outcome of this research has potential applications in the preliminary design of deep tunnels in squeezing ground. [ABSTRACT FROM AUTHOR]

• Mathematical analytical model of a tunnel using compressible layer is established. • Potential functions and related coefficients in tunnel model are provided. • Effect of compressible layer on tunnel performance is theoretically investigated. The application of compressible layers is considered to be the most promising solution for solving the problem of large deformations in deep soft-rock tunnels. However, although significant effort has been devoted to understanding its mechanical working, the effect of the compressible layer has not been completely revealed. This study theoretically predicts the mechanical response of a deep soft-rock large deformation tunnel by applying a compressible layer. The theoretical model involves a circular tunnel, which is supported by a compressible layer and concrete lining, and subjected to a non-hydrostatic stress field. The influence of the tunnel face advancement is described by the stress release coefficient, and the three-stage deformation characteristics (elastic–yielding–compaction) of the compressible layer material are considered in this model. The entire tunnel deformation process is divided into unlined and lined (further subdivided into elastic, yielding, and compaction phases of the compressible layer material) phases. A series of complex potential functions in different media (rock, compressible layer, and concrete lining) and at different phases is provided; subsequently, the unknown coefficients in these functions are determined using the stress balance and displacement continuity conditions at different interfaces. Thus, the analytical solutions for tunnel displacement and support pressure at different phases are obtained. Good agreement between the numerical and analytical results is observed after performing the numerical simulation to validate the reliability and feasibility of the proposed analytical derivation. Finally, a parametric sensitivity investigation is conducted by including the yielding stress of the filling material, yielding length of the compressible layer, and installation time of the support. Adequate attention is paid to the tunnel displacement and support pressure on the 100th day and their development laws at the positions of θ = 90°, 45°, and 0° during the first 100 days. Some interesting findings are presented, and useful design suggestions for the compressible layer are provided. [ABSTRACT FROM AUTHOR]

Drawing upon recent post-political critiques on ineffective participation and urban planning, this paper reflects on the challenges facing participatory and collaborative planning in China's latest neighborhood regeneration practices. In 2017, Guangzhou launched a new micro-scale neighborhood regeneration program that shifted the discursive emphasis on participatory planning while China strives to create a new national image of a "people's city". This paper critically examines the implementation of old community renovation policies in 32 Chinese provinces and 776 neighborhood regeneration projects in Guangzhou. By examining the objectives and outcomes of legitimate power over participation, we uncover institutional conditions, implementation issues, and local responses in different participatory planning configurations. We found that a "co-production" model emerged in China, highlighting the role of institutionalized participatory planning activities. The conclusion is threefold: 1) Shared objectives in the emerging neighborhood regeneration discourse constitute legitimate power over participation in China's neighborhood regeneration; 2) The outcomes of legitimate power over participation are reflected in the local responses to the "co-production" activities; and 3) The "co-production" model—to produce planning schemes through co-design and joint-negotiation among multi-scalar actors including planners and residents—performs as an alternative to immature collaborative planning in China. Local governments can skillfully avoid direct confrontations with residents by introducing the function of community planners. These institutional arrangements of "co-production" have profoundly impacted the reshuffling of the state-society relationship in post-political China. While the implementation of China's latest neighborhood regeneration policy shows post-political risks in terms of depoliticized narratives, instrumentalized planning strategies, and technicized planning tools, we find "co-production" to be fruitful in promoting substantive participation and stimulating the accumulation of local knowledge. • An analytical framework to conceptualize the legitimate power of participation in China's emerging small-scale neighborhood regeneration program. • A response to the debate between two currents in the post-political context—consensus-oriented and conflict-based. • Critically examines the implementation of old community renovation policies in 32 Chinese provinces and the participatory planning practices of 776 projects in Guangzhou. • "Co-production" reflects both the objective and the outcome of legitimate power embodied in the neighborhood regeneration process. [ABSTRACT FROM AUTHOR]

Electrostatic motor can work as a supplement to the electromagnetic motor due to its simple structure, low cost, light weight, and high efficiency. This paper presents a dielectric-gas-based single-phase electrostatic motor with simplified construction. The motor design is focused on increasing the capacitance, subsequently the torque, to make the electrostatic motors competitive with the electromagnetic ones. Three-dimensional (3-D) finite element analysis (FEA) simulation and optimization process of the electrostatic motor is performed. A 50 W electrostatic motor with the torque of 0.25 N·m, which is the same order in magnitude with the fluid-filled electrostatic machine and induction machine at the similar power level, is designed. Losses including the friction loss, windage loss, and dielectric loss are predicted. Thermal fields are analyzed using FEA and the electrostatic motor presented can work stably at high ambient temperature. 3-D printing is used to build a prototype machine to eliminate the process of mould manufacture and achieve a weight reduction. Predicted capacitance of machine is compared with measured result and good agreement is achieved. [ABSTRACT FROM AUTHOR]

The LC resonance between the line inductor and the dc-link film capacitor is an important concern in the reduced dc-link capacitance interior permanent magnet synchronous motor drive system. In this paper, an active damping method based on the virtual damping resistor is applied to suppress the LC resonance and improve the drive system stability. The performance of the damping resistor is analyzed in a systematic level, and possible configurations have been analyzed to obtain the optimal solution, which is proved to be the inductor current feedback (ICF) damping method. In order to realize the equivalent damping effect, the dc-link voltage feedback is applied to emulate the ICF-based active damping method by a step-by-step approach. Meanwhile, the grid voltage distortion will stimulate additional harmonics of the grid current in the reduced dc-link capacitance motor drives. Hence a feedforward compensation method is applied to suppress the grid current distortion arising from the distorted grid voltage, which has not been investigated in the previous related researches. Harmonics of the grid current are reduced and requirements of EN61000-3-2 can be satisfied by applying the proposed method. Experiments on a compressor drive platform equipped with the reduced dc-link capacitance are performed to verify the effectiveness of the proposed method. [ABSTRACT FROM AUTHOR]

Corynebacterium glutamicum (C. glutamicum), an important industrial workhorse, is capable of efficiently producing a variety of value-added chemicals and fuels beyond amino acids. C. glutamicum has a broad natural substrate spectrum and can simultaneously utilize various carbon sources in blends. The substrate spectrum of C. glutamicum has been further extended by detailed knowledge of carbon core metabolism and well-established genetic tools and engineering strategies. At present, many pathways have been successfully engineered in C. glutamicum for access to alternative renewable sources to produce natural or non-natural products, making C. glutamicum a promising and favorable microbial cell factory. In this review, we mainly focus on synthetic biology and metabolic engineering strategies for developing synthetic strains that grow on renewable sources to produce the target products. At the same time, we also explore the promotion and future challenges of existing synthetic biology platforms for industrial platform microorganism metabolic engineering efforts. [ABSTRACT FROM AUTHOR]

The potential of macroalgae Laminaria digitata as substrate for bioelectricity production was examined in a microbial fuel cell (MFC). A maximum voltage of 0.5 V was achieved without any lag time due to the high concentration of glucose and mannitol in the hydrolysate. Total chemical oxygen demand removal efficiency reached over 95% at the end of batch run. Glucose and mannitol were degraded through isobutryrate as intermediate. The 16S rRNA gene high throughout sequencing analysis of anodic biofilm revealed complex microbial composition dominated by Bacteroidetes (39.4%), Firmicutes (20.1%), Proteobacteria (11.5%), Euryarchaeota (3.1%), Deferribacteres (1.3%), Spirochaetes (1.0%), Chloroflexi (0.7%), Actinobacteria (0.5%), and others (22.4%). The predominance of Bacteroidetes , Firmicutes and Proteobacteria demonstrated their importance for substrate degradation and simultaneous power generation. These results demonstrate that macroalgae hydrolysate can be used as a renewable carbon source of microbial electrochemical systems for various environmental applications. [ABSTRACT FROM AUTHOR]

A key challenge for ammonia monitoring during nitrogen removal process is the extra cost and toxic reagent consuming. Herein the feasibility of current generated by an integrated microbial electrolysis cell (MEC) - nitrification reactor as an indicator of initial ammonia levels (NH 3 /NH 4 + ) in wastewater was explored. In this loop system, ammonia was first oxidized to nitrate in the nitrification reactor, and then the effluent was introduced into the cathode of MEC where nitrate was reduced as electron acceptor. The correlation between current and ammonia concentration was first investigated with synthetic ammonia-rich wastewater. A good linear relationship (R 2  = 0.9419) was observed between current (0.5130–3.906 mA) and ammonia levels (0–62.1 mg NH 4 + -N/L). Such linear relationship was always obtained regardless of the tested external power supply or wastewater pH. The external electrochemical cell was proved to be an effective pre-conditioning method to remove the disturbance from other possible electron acceptors. Finally, the integrated system was further tested with real waste streams and the results showed no significant difference (p > 0.05) with measurements by conventional methods. This study, for the first time, demonstrated the potential application of the integrated MEC - nitrification system for ammonia monitoring in addition to water treatment. [ABSTRACT FROM AUTHOR]

Extensive studies of coupled dynamical systems have shown that under certain underlying interactions, all the individual subsystems may cease totally their intrinsic oscillations and are stabilized to a homogeneous steady state, which is known as amplitude death (AD). The presence of higher-order many-body interactions can overcome the limitation of first-order pairwise interactions, and more vividly model the emergent dynamics in real-world systems. However, it is still unclear whether and under which conditions AD can be achieved in the presence of higher-order interactions. In this work, by considering a simplicial complex of coupled Stuart–Landau oscillators, we investigate the impacts of first-order (pairwise) and second-order (three-body) interactions on the emergence of AD dynamics. The results show clear evidence that the higher-order interactions can facilitate the onset of AD dynamics with a lower coupling strength. In particular, we first derive the necessary condition to determine the onset of AD by performing linear stability analysis. Then we show, via numerical simulations, that AD can be achieved by either first-order or second-order interactions only, and the required coupling strength of first-order interactions is much higher than the second-order ones. Finally, we conclude that the physical mechanism is due to the reflection of interaction units between oscillators, that is, the network with second-order interactions allows the nodes to involve more interactions simultaneously than the one with first-order interactions. These results shed a new insight into the generation of AD phenomenon and reveal that the higher-order interactions can serve as a rather efficient approach to quench the rhythmic activities. [ABSTRACT FROM AUTHOR]

[Display omitted] • A one-dimensional hierarchical Bi 2 O 2 CO 3 is developed as high-performance photocatalyst. • The hierarchical Bi 2 O 2 CO 3 displays efficient photocatalytic reduction of Cr(Ⅵ) and bisphenol A under solar light. • Surface-assembly forms one-dimensional hierarchical structure along one-dimensional direction. • One-dimensional hierarchical structure enhances light harvesting and accelerates surface reaction kinetics. High-performance photocatalysts are highly needed for removing pollutants from water under solar light. A one-dimensional (1D) hierarchical Bi 2 O 2 CO 3 is developed through a self-assembly route by using ordered nanosheets. During reaction process, sodium citrate decomposes and releases CO 3 2– which in-situ reacts with Bi 2 O 3 to form Bi 2 O 2 CO 3 nanosheets exposed with (0 0 1) crystal facets. Each non-decomposed citrate ion (Cit3-) with tree carboxylate groups adsorb on some (0 0 1) crystal facets and compel the Bi 2 O 2 CO 3 nanosheets parallelly grow up, finally the 1D hierarchical Bi 2 O 2 CO 3 structure self-assembled by ordered nanosheets is obtained. The presented Bi 2 O 2 CO 3 exhibits an outstanding photocatalytic activity including 100 mg/L of Cr(VI) solution can be completely reduced in 10 min under solar light. Moreover, bisphenol A is also degraded efficiently. It is ascribed to special hierarchical structure of Bi 2 O 2 CO 3 which can not only increases the surface area, but also enhances light utilization, improving the photocatalytic performance. [ABSTRACT FROM AUTHOR]

In this work, we introduce an extended gradient method that employs the gradients of the preceding two iterates to construct the search direction for the purpose of solving the centralized and decentralized smooth and strongly convex functions. Additionally, we establish the linear convergence for iterate sequences in both the centralized and decentralized manners. Furthermore, the numerical experiments demonstrate that the centralized extended gradient method can achieve faster acceleration than the compared algorithms, and the search direction also exhibits the capability to improve the convergence of the existing algorithms in both two manners. [ABSTRACT FROM AUTHOR]

There are lots of reports about alleviation of NAFLD by dietary supplements of betaine. However, it remains unclear whether maternal betaine supplementation can also ameliorate NAFLD in offspring. Hence, twenty pregnant rats were fed with a basal diet with or without betaine (1%), and then the female offspring rats were raised at 3 months of age followed by 3 weeks of physiological saline or dexamethasone in a dose of 0.1 mg/kg body mass every day via intraperitoneal injection. In this study, maternal betaine supplementation significantly (P<.05) reduced the increase of hepatic triglycerides concentration in dexamethasone-induced rats, which is associated with the expression of hepatic lipogenic genes (ACC1, FASN and SCD1). Moreover, the hypomethylation of lipogenic genes in dexamethasone-induced rats were reserved by prenatal betaine exposure. Furthermore, the increase of hepatic GR or SP1 content in dexamethasone-injected rats were significantly decreased (P<.05), which were in line with the binding of GR or SP1 to lipogenic genes, in betaine -exposed rats. Together, these results suggest that maternal betaine supplementation attenuates dexamethason-induced fatty liver in the female adult offspring rats, which may be attributed to DNA methylation and GR or SP1-mediated the regulation of lipogenic genes. [ABSTRACT FROM AUTHOR]

Ammonia monitoring is important to control anaerobic digestion (AD) process due to inhibition effect. Here, an electrolysis cell (EC) was integrated with a complete nitrification reactor as an alternative approach for online monitoring of ammonia during AD processes. The AD effluent was pumped into nitrification reactor to convert ammonia to nitrate, followed by the introduction of nitrate-rich effluent to EC cathode. It was first evaluated with synthetic ammonia-rich digesters and was observed that the current at 5 min were linearly corresponding to the ammonia levels (from 0 to 7.5 mM NH 4 + -N, R 2  = 0.9673). The linear relationship was always observed regardless of different wastewater pH and external voltage. Pre-removal of other electron acceptors from digestate at cathode could eliminate their disturbances to sensor performance. Finally, the accuracy of biosensor was verified with real digestate test. The simple and reliable biosensor showed great promising for online ammonia monitoring of AD processes. [ABSTRACT FROM AUTHOR]

In order to mitigate harmonics of the grid input current, passive filters are applied widely in the power electric systems. The LC resonance and the negative input impedance are important concerns in the reduced dc-link capacitance motor drive system. In this paper, an active damping control method is proposed to suppress the LC resonance by the direct damping current approach, which can formulate the pole distribution of the drive system. Different control laws have been analyzed, and the stability analysis is evaluated by the Routh–Hurwitz criterion. Meanwhile, the active damping control method is realized by the voltage command, which can overcome the limited bandwidth of the current controller. Since the generation of the direct damping current only depends on the dc-link voltage, the proposed active damping control method is robust. Compared with the virtual impedance methods, parameters can be accurately optimized by Bode diagrams after adopting the proposed active damping method. Simulation and experimental results are provided to verify the effectiveness of the proposed method. [ABSTRACT FROM PUBLISHER]