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Solid oxide fuel cells (SOFC) have gained increasing attention as they generate electricity with higher energy conversion efficiency. Current studies are focused on the rigorous mechanism development on the experimental scale or thermodynamic modeling for SOFC on the industrial scale. Given the practical application concerns, it is imperative to integrate the reaction mechanism with large-scale SOFC system optimization. Toward this goal, this paper proposes a novel mechanism-based kinetic modeling method for optimization of SOFC, which includes aspects of electrochemistry, diffusion phenomena, and microscale kinetic modeling. Two plug flow reactors are adopted to simulate the cathode and anode of the component stack, respectively. The reaction distance is differentiated, and the model is solved in each differential unit. The electrochemical process and internal methane reforming process in the anode are coupled through hydrogen allocation, and the oxygen in the cathode is optimized according to the microscale kinetic modeling in each differential unit. The accuracy of the model is verified by comparison with the results of simulation experiments in the literature, where the average relative error is about 5%. Sensitivity analysis is performed to recognize the key parameters and explore their effects on stack performance improvements. The result shows that the diameter of PFR has the larger effect on the voltage, the mole fraction of H2, H2O, and CH4, and the reaction time, compared with the length of PFR and the amount of catalyst. The major contributions derived from this work are of significant aid in providing guidelines for future development of kinetic modeling of other fuel cells.

Since the production process of ethylene to ethylene oxide (EO) is highly energy-intensive, it is necessary to perform a whole process heat integration. However, due to the technical barriers, it is always a challenge to design the heat integration system while optimizing the process parameters by mechanistic models. In response to this issue, this study presented a novel surrogate model-based framework that allows for the seamless integration of process optimization and heat exchanger network (HEN) design. The EO production process is modeled and simulated to provide the essential data for surrogate model training. Considering the inherent complexity of the process and the challenges associated with model training, the whole production process is decomposed into parts and the output parameters relevant to heat integration are included within the surrogate models training by Artificial Neural Network. Building upon these preliminary steps, a flexible optimization framework built upon the Genetic Algorithm, integrating the developed process surrogate model and any HEN synthesis model, is constructed to achieve synchronous optimization. The results show that the obtained process saves 22.93 % utility cost and finally leads to a 2.60 % increase in total profit than the alternative designed by the conventional stepwise method, showing the priority of the proposed method.

With the increasing and aging of global population, there is a dramatic rise in the demand for implants or substitutes to rehabilitate bone-related disorders which can considerably decrease quality of life and even endanger lives. Though titanium and its alloys have been applied as the mainstream material to fabricate implants for load-bearing bone defect restoration or temporary internal fixation devices for bone fractures, it is far from rare to encounter failed cases in clinical practice, particularly with pathological factors involved. In recent years, smart stimuli-responsive (SSR) strategies have been conducted to functionalize titanium implants to improve bone regeneration in pathological conditions, such as bacterial infection, chronic inflammation, tumor and diabetes mellitus, etc.SSR implants can exert on-demand therapeutic and/or pro-regenerative effects in response to externally applied stimuli (such as photostimulation, magnetic field, electrical and ultrasound stimulation) or internal pathology-related microenvironment changes (such as decreased pH value, specific enzyme secreted by bacterial and excessive production of reactive oxygen species). This review summarizes recent progress on the material design and fabrication, responsive mechanisms, and in vitroand in vivoevaluations for versatile clinical applications of SSR titanium implants. In addition, currently existing limitations and challenges and further prospective directions of these strategies are also discussed.

It is a challenge to separate ternary azeotropic systems containing a large amount of one component since the vaporization of the high-content component means huge energy consumption. Incorporating preconcentration into extractive distillation processes can result in energy conservation. Toward this end, this work develops improved indirect extractive distillation with integrated distillation column (IIED-IDC) processes as well as one conventional indirect extractive distillation (CIED) process and three conventional indirect extractive distillation with preconcentration (CIED-PRE) processes for separating such azeotropes. The innovative characteristics of the proposed IIED-IDC schemes are that the preconcentration function is integrated with alternative functions (solvent recovery/extractive distillation functions) in the IDC. Three cases about the separation of methanol/acetonitrile/benzene multiazeotropic systems are used to prove the effectiveness of the presented processes. The simulation-based optimization results display that the IIED-IDC processes can achieve an average 33.63%/13.27% lower economic costs and 37.12%/14.81% lower energy costs than the CIED and CIED-PRE configurations.

MicroRNAs (miRNAs) influence several biological processes involved in human disease. Biological experiments for verifying the association between miRNA and disease are always costly in terms of both money and time. Although numerous biological experiments have identified multi-types of associations between miRNAs and diseases, existing computational methods are unable to sufficiently mine the knowledge in these associations to predict unknown associations. In this study, we innovatively propose a heterogeneous graph attention network model based on meta-subgraphs (MSHGANMDA) to predict the potential miRNA-disease associations. Firstly, we define five types of meta-subgraph from the known miRNA-disease associations. Then, we use meta-subgraph attention and meta-subgraph semantic attention to extract features of miRNA-disease pairs within and between these five meta-subgraphs, respectively. Finally, we apply a fully-connected layer (FCL) to predict the scores of unknown miRNA-disease associations and cross-entropy loss to train our model end-to-end. To evaluate the effectiveness of MSHGANMDA, we apply five-fold cross-validation to calculate the mean values of evaluation metrics Accuracy, Precision, Recall, and F1-score as 0.8595, 0.8601, 0.8596, and 0.8595, respectively. Experiments show that our model, which primarily utilizes multi-types of miRNA-disease association data, gets the greatest ROC-AUC value of 0.934 when compared to other state-of-the-art approaches. Furthermore, through case studies, we further confirm the effectiveness of MSHGANMDA in predicting unknown diseases.

Background and Objectives: The oral bioavailability of withangulatin A (WA) is low and may undergo first-pass metabolism because of the presence of two esters bonds. This study aimed to identify the hydrolysis behavior and mechanism of WA, thus enriching its structure-pharmacokinetic relationship. Methods: The in vivo pharmacokinetic studies of WA in rats were first investigated, followed by in vitro assays including metabolic stability, phenotyping identification and metabolic kinetics assays. After screening out the responsible enzymes with higher catalytic capacity, molecular docking study was performed to demonstrate the interaction mode between WA and metabolic enzymes. Then, metabolites in human serum albumin (HSA) were identified by LC-TOF-MS/MS. Results: In rats, the oral bioavailability of WA was only 2.83%. In vitro, WA was hydrolyzed in both rat and human plasma and could not be inhibited by selective esterase inhibitors. Physiologic concentration of HSA not recombinant human carboxylesterases (rhCES) could significantly hydrolyze WA, and it had a similar hydrolytic capacity with human plasma to WA. Furthermore, WA could stably bind to HSA by forming hydrogen bonds with Lys199 and Arg410, accompanied by the metabolic reaction of the lactone ring opening. Conclusion: The study showed that WA underwent obvious hydrolysis in rat and human plasma, which implied a strong first-pass effect. Serum albumin rather than common esterases primarily contributed to the hydrolytic metabolism of WA in plasma.

Osteoarthritis (OA) is a highly prevalent whole-joint disease that causes disability and pain and affects a patient's quality of life. However, currently, there is a lack of effective early diagnosis and treatment. Although stem cells can promote cartilage repair and treat OA, problems such as immune rejection and tumorigenicity persist. Extracellular vesicles (EVs) can transmit genetic information from donor cells and mediate intercellular communication, which is considered a functional paracrine factor of stem cells. Increasing evidences suggest that EVs may play an essential and complex role in the pathogenesis, diagnosis, and treatment of OA. Here, we introduced the role of EVs in OA progression by influencing inflammation, metabolism, and aging. Next, we discussed EVs from the blood, synovial fluid, and joint-related cells for diagnosis. Moreover, we outlined the potential of modified and unmodified EVs and their combination with biomaterials for OA therapy. Finally, we discuss the deficiencies and put forward the prospects and challenges related to the application of EVs in the field of OA.

Objective: Although existing assist-as-needed (AAN) controllers have been designed to adapt the robotic assistance to patients' movement performance, they ignore patient's active participation. This study proposed a voluntary AAN (VAAN) controller considering both movement performance and active participation for an ankle rehabilitation robot. Methods: According to the trajectory tracking error of the human-robot cooperation movement, the controller can switch among four working modes, including robot-resist, free, robot-assist, and robot-dominant mode. In order to reflect patients’ active participation, the voluntary torque of the ankle joint was estimated by an EMG-driven musculoskeletal model. The control torque in robot-resist, free, and robot-assist mode was determined by the voluntary torque of ankle joint multiplied by an assistance ratio to encourage subjects’ active participation, and a stiff torque was provided in robot-dominant mode. The controller was evaluated with 2 healthy subjects and 5 stroke patients on an ankle rehabilitation robot to investigate the clinical impact on the stroke patients. Results: The experiment results showed that as patients’ disability level increased, the trajectory tracking error increased and the proportion of human-dominant time and the voluntary torque of ankle joint decreased. Moreover, the results showed that the proposed VAAN controller achieved higher human contribution ratio than that of previous studies. Conclusion: The proposed VAAN controller can adapt the working mode to the movement performance and promote the subjects to participate actively. Significance: Based on its performance, the proposed VAAN controller has potential for use in robot-assisted rehabilitation.

This paper proposes a decoupling power balancing strategy with reduced current sensors for the two phase interleaved neutral point clamped DC/DC converter (NPCDC) applied in energy storage system (ESS). With the analysis of the NPCDC operation principle, an equivalent two voltage level analysis method is derived. On this basis, the power balancing strategy based on the total current time-sharing sampling method is proposed. Compared with the traditional strategy, the proposed strategy only requires two current sensors, reducing the number of current sensors by half. Meanwhile, the power balancing control is decoupled with output voltage control and capacitor voltage balancing control, which is helpful to simply the controller design. The small signal model of the proposed strategy based on the equivalent two voltage level analysis method is studied, and the controller design method is also presented in the paper. At last, the effectiveness of the proposed strategy is verified through an energy storage experimental platform, and the experimental results are presented and discussed.

The coronavirus disease 2019 (COVID-19), caused by the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), has highlighted the pivotal role of the immune response in determining the progression and severity of viral infections. In this paper, we review the most recent studies on the complicated dynamics between SARS-CoV-2 and the host immune system, highlight the importance of understanding these dynamics in developing effective treatments and formulate potent management strategies for COVID-19. We describe the activation of the host's innate immunity and the subsequent adaptive immune response following infection with SARS-CoV-2. In addition, the review emphasizes the immune evasion strategies of the SARS-CoV-2, including inhibition of interferon production and induction of cytokine storms, along with the resulting clinical outcomes. Finally, we assess the efficacy of current treatment strategies, including antiviral drugs, monoclonal antibodies, and anti-inflammatory treatments, and discuss their role in providing immunity and preventing severe disease.

Yolk Peritonitis can lead to a rapid decline in egg production, which seriously affects the health of laying hens and the profitability of chicken farms. Escherichia coli(E. coli) is the most common cause of yolk peritonitis in laying hens. In this study, bacterial samples were collected from the ovaries and fallopian tubes of laying hens with suspected yolk peritonitis from a laying farm in Jiangsu Province, and their pathogenicity and drug resistance were investigated. Initially, morphological and biochemical detection methods were employed to isolate and identify the pathogenic bacteria. The results showed that a total of 16 strains of E. coliwere isolated from laying hens with yolk peritonitis. Subsequently, the drug resistance and pathogenicity of a randomly selected E. colistrain were analyzed and predicted by genome sequencing technology, and the drug resistance of E. coli was verified by drug sensitivity test and PCR. Finally, the virulence was verified by infection experiment in mice. The study revealed that the egg-yolk peritonitis in laying hens was caused by E. coliinfection, and the genome sequencing analysis revealed that the bacteria had multidrug resistance and high virulence. The drug susceptibility testing indicates that E. coliexhibited resistance to aminoglycosides, β-lactam, macrolides, fluoroquinolones, and sulfonamides. In this study, resistance genes including KdpE, aadA5, APH(3 ")-ID, APH(6)-ID, and TEM-1 were identified, and their expression levels varied across different stages of bacterial growth. The results of virulence analysis indicated a mortality rate of 50% in mice infected with E. coliat a concentration of 2.985 × 107CFU/mL. E. coliinfection resulted in damage to various tissues and organs in mice, with the intestinal tissue structure being the most severely affected. This study provides a reference for the study of drug resistance mechanisms in E. coliand provides valuable insights into the selection of drugs for the treatment of vitelline peritonitis.

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The effective repair of large bone defects remains a major challenge due to its limited self‐healing capacity. Inspired by the structure and function of the natural periosteum, an electrospun biomimetic periosteum is constructed to programmatically promote bone regeneration using natural bone healing mechanisms. The biomimetic periosteum is composed of a bilayer with an asymmetric structure in which an aligned electrospun poly(ε‐caprolactone)/gelatin/deferoxamine (PCL/GEL/DFO) layer mimics the outer fibrous layer of the periosteum, while a random coaxial electrospun PCL/GEL/aspirin (ASP) shell and PCL/silicon nanoparticles (SiNPs) core layer mimics the inner cambial layer. The bilayer controls the release of ASP, DFO, and SiNPs to precisely regulate the inflammatory, angiogenic, and osteogenic phases of bone repair. The random coaxial inner layer can effectively antioxidize, promoting cell recruitment, proliferation, differentiation, and mineralization, while the aligned outer layer can promote angiogenesis and prevent fibroblast infiltration. In particular, different stages of bone repair are modulated in a rat skull defect model to achieve faster and better bone regeneration. The proposed biomimetic periosteum is expected to be a promising candidate for bone defect healing. An electrospun biomimetic periosteum with an asymmetric structure is prepared through aligned and coaxial electrospinning for programed promotion of bone regeneration. This biomimetic periosteum exhibits controlled release of multiple agents, enabling regulation of the inflammatory, angiogenic, and osteogenic phases that are essential for bone healing. It demonstrates good efficacy in promoting bone regeneration in a rat skull defect model.

Fatty liver hemorrhagic syndrome (FLHS) is a prevalent metabolic disorder observed in egg-laying hens, characterized by fatty deposits and cellular steatosis in the liver. Our preliminary investigations have revealed a marked decrease in the concentration of butyric acid in the FLHS strain of laying hens. It has been established that sodium butyrate (NaB) protects against metabolic disorders. However, the underlying mechanism by which butyrate modulates hepato-lipid metabolism to a great extent remains unexplored. In this study, we constructed an isolated in vitro model of chicken primary hepatocytes to induce hepatic steatosis by free fatty acids (FFA). Our results demonstrate that treatment with NaB effectively mitigated FFA-induced hepatic steatosis in chicken hepatocytes by inhibiting lipid accumulation, downregulating the mRNA expression of lipo-synthesis-related genes (sterol regulatory element binding transcription factor 1 (SREBF1), acetyl-CoA carboxylase 1(ACC1), fatty acid synthase (FASN), stearoyl-CoA desaturase 1 (SCD1), liver X receptor α (LXRα), 3-hydroxy-3-methylglutaryl-CoA reductase (HMGR)) (P< 0.05), and upregulating the mRNA and protein expression of AMP-activated protein kinase α1 (AMPKα1), peroxisome proliferator-activated receptor α (PPARα), and carnitine palmitoyl-transferase 1A (CPT1A) (P< 0.05). Moreover, AMPK and PPARα inhibitors (Compound C (Comp C) and GW6471, respectively) reversed the protective effects of NaB against FFA-induced hepatic steatosis by blocking the AMPK/PPARα pathway, leading to lipid droplet accumulation and triglyceride (TG) contents in chicken primary hepatocytes. With these findings, NaB can alleviate hepatocyte lipoatrophy injury by activating the AMPK/PPARα pathway, promoting fatty acid oxidation, and reducing lipid synthesis in chicken hepatocytes, potentially being able to provide new ideas for the treatment of FLHS.

ABSTRACTLong non-coding RNA (lncRNA) TSPEAR-AS2 (TSPEAR Antisense RNA 2) participates in many human diseases, while its roles in rheumatoid arthritis (RA) are unknown. Plasma expression levels of TSPEAR-AS2 and microRNA (miR)-212-3p in both RA patients and healthy controls were measured by RT-qPCR. Diagnostic potentials of plasma TSPEAR-AS2 and miR-212-3p were assessed by ROC curve analysis. Normalized expression levels of TSPEAR-AS2 and miR-212-3p were subjected to Pearson’s correlation coefficient to evaluate their corrections. TSPEAR-AS2 was significantly downregulated in RA patients, while plasma expression levels of miR-212-3p were significantly increased in RA patients. The expression of TSPEAR-AS2 and miR-212-3p showed promising diagnostic value for RA. Plasma expression levels of TSPEAR-AS2 and miR-212-3p were significantly and inversely correlated in RA patients but not in healthy controls. Besides, overexpression of TSPEAR-AS2 decreased the apoptosis of RA HFLSs, while miR-212-3p increased cell apoptosis. In addition, miR-212-3p attenuated the effects of overexpression of TSPEAR-AS2. Overexpression of TSPEAR-AS2 decreased the expression levels of miR-212-3p in HFLS, while overexpression of miR-212-3p did not affect the expression of TSPEAR-AS2. In conclusion, TSPEAR-AS2 is downregulated in RA and its overexpression can decrease the apoptosis of RA HFLSs by downregulating miR-212-3p.

The electrocatalytic HMF oxidation reaction (HMFOR) is one of the promising technologies for the valorization of biomass derivatives and potential replacements for the energy-consuming oxygen evolution reaction (OER). For the most investigated Ni-based electrode, the in situreconstruction from Ni(OH)2to NiOOH is hardly avoidable during the electro-oxidation reaction, which is also a highly indispensable prerequisite towards HMFOR. Herein, we developed an efficient strategy of sacrificing W to investigate the effect of surface defects on the self-reconstruction of Ni for promoting HMFOR. It was rationalized that the selective and rapid exsolution of the W species from the as-prepared NiW layer created a porous structure and induced lattice defects on the surface, which facilitated the ion and electron transportation, and further promoted the in situreconstruction for the formation of higher oxidated Ni with superior activity for HMFOR. This work offers a novel and low-cost means to enrich the active sites for the electrocatalytic upgrading of HMF and other bio-derived platforms.

In order to develop high-performance adsorbents to remove toxic methylene blue (MB) from wastewater, palygorskite (Plg) was utilized as a template to prepare palygorskite/carbon (Plg/C) composites by using a hydrothermal reaction in the presence of glucose. The porous Plg/C composites were then activated with ZnCl2. The effects of the dose of the activator and the activation temperature on the crystal structure, micro-morphology, specific surface area, and adsorption performance of the porous Plg/C composites were studied systematically here. X-ray diffraction (XRD) and scanning electron microscopy (SEM) results indicated that the crystal structure of Plg was destroyed during the activation process and irregular porous carbon was closely attached to the residual aluminosilicate skeleton. The activation was optimized at 400°C with a ZnCl2:Plg/C impregnation ratio of 2:1. The sample had a specific surface area of 1497.88 m2/g, together with a total pore volume and micropore volume of 1.0355 and 0.5464 cm3/g, respectively. The MB adsorption capacity was 381.04 mg/g. Such inexpensive, high-performance, porous Plg/C composites could find potential applications in wastewater treatment.

Purpose: Lack of biomechanical force model of soft tissue hinders the development of virtual surgical simulation in maxillofacial surgery. In this study, a physical model of facial soft tissue based on real biomechanical parameters was constructed, and a haptics-enabled virtual surgical system was developed to simulate incision-making process on facial soft tissue and to help maxillofacial surgery training. Methods: CT data of a 25-year-old female patient were imported into Mimics software to reconstruct 3D models of maxillofacial soft and skeletal tissues. 3dMD stereo-photo of the patient was fused on facial surface to include texture information. Insertion and cutting parameters of facial soft tissue measured on fresh cadavers were integrated, and a maxillofacial biomechanical force model was established. Rapid deformation and force feedback were realized through localized deformation algorithm and axis aligned bounding box (AABB)-based collision detection. The virtual model was validated quantitatively and qualitatively. Results: A patient-specific physical model composed of skeletal and facial soft tissue was constructed and embedded in the virtual surgical system. Insertion and cutting in different regions of facial soft tissue were simulated using omega 6, and real-time feedback force was recorded. The feedback force was consistent with acquired force data of experiments conducted on tissue specimen. Real-time graphic and haptic feedback were realized. The mean score of the system performance was 3.71 given by surgeons in evaluation questionnaires. Conclusion: The maxillofacial physical model enabled operators to simulate insertion and cutting on facial soft tissue with realization of realistic deformation and haptic feedback. The combination of localized deformation algorithm and AABB-based collision detection improved computational efficiency. The proposed virtual surgical system demonstrated excellent performance in simulation and training of incision-making process.

Upregulated de novo lipogenesis (DNL) plays a pivotal role in the progress of the nonalcoholic fatty liver disease (NAFLD). Cytoplasmic citrate flux, mediated by plasma membrane citrate transporter (SLC13A5), mitochondrial citrate carrier (SLC25A1), and ATP-dependent citrate lyase (ACLY), determines the central carbon source for acetyl-CoA required in DNL. Curcumin, a widely accepted dietary polyphenol, can attenuate lipid accumulation in NAFLD. Here, we first investigated the lipid-lowering effect of curcumin against NAFLD in oleic and palmitic acid (OPA)-induced primary mouse hepatocytes and high-fat plus high-fructose diet (HFHFD)-induced mice. Curcumin profoundly attenuated OPA- or HFHFD-induced hyperlipidemia and aberrant hepatic lipid deposition via modulating the expression and function of SLC13A5 and ACLY. The possible mechanism of curcumin on the citrate pathway was investigated using HepG2 cells, HEK293T cells transfected with human SLC13A5, and recombinant human ACLY. In OPA-stimulated HepG2 cells, curcumin rectified the dysregulated expression of SLC13A5/ACLY possibly via the AMPK–mTOR signaling pathway. Besides, curcumin also functionally inhibited both citrate transport and metabolism mediated by SLC13A5 and ACLY, respectively. These findings confirm that curcumin improves the lipid accumulation in the liver by blocking citrate disposition and hence may be used to prevent NAFLD.

Metabolic reprogramming is associated with NLRP3 inflammasome activation in activated macrophages, contributing to inflammatory responses. Tanshinone IIA (Tan-IIA) is a major constituent from Salvia miltiorrhizaBunge, which exhibits anti-inflammatory activity. In this study, we investigated the effects of Tan-IIA on inflammation in macrophages in focus on its regulation of metabolism and redox state. In lipopolysaccharides (LPS)-stimulated mouse bone marrow-derived macrophages (BMDMs), Tan-IIA (10 μM) significantly decreased succinate-boosted IL-1β and IL-6 production, accompanied by upregulation of IL-1RA and IL-10 release via inhibiting succinate dehydrogenase (SDH). Tan-IIA concentration dependently inhibited SDH activity with an estimated IC50of 4.47 μM in LPS-activated BMDMs. Tan-IIA decreased succinate accumulation, suppressed mitochondrial reactive oxygen species production, thus preventing hypoxia-inducible factor-1α (HIF-1α) induction. Consequently, Tan-IIA reduced glycolysis and protected the activity of Sirtuin2 (Sirt2), an NAD+-dependent protein deacetylase, by raising the ratio of NAD+/NADH in activated macrophages. The acetylation of α-tubulin was required for the assembly of NLRP3 inflammasome; Tan-IIA increased the binding of Sirt2 to α-tubulin, and thus reduced the acetylation of α-tubulin, thus impairing this process. Sirt2 knockdown or application of Sirt2 inhibitor AGK-2 (10 μM) neutralized the effects of Tan-IIA, suggesting that Tan-IIA inactivated NLRP3 inflammasome in a manner dependent on Sirt2 regulation. The anti-inflammatory effects of Tan-IIA were observed in mice subjected to LPS challenge: pre-administration of Tan-IIA (20 mg/kg, ip) significantly attenuated LPS-induced acute inflammatory responses, characterized by elevated IL-1β but reduced IL-10 levels in serum. The peritoneal macrophages isolated from the mice displayed similar metabolic regulation. In conclusion, Tan-IIA reduces HIF-1α induction via SDH inactivation, and preserves Sirt2 activity via downregulation of glycolysis, contributing to suppression of NLRP3 inflammasome activation. This study provides a new insight into the anti-inflammatory action of Tan-IIA from the respect of metabolic and redox regulation.

Vascular diseases are the most prevalent cause of ischemic necrosis of tissue and organ, which even result in dysfunction and death. Vascular regeneration or artificial vascular graft, as the conventional treatment modality, has received keen attentions. However, small-diameter (diameter < 4 mm) vascular grafts have a high risk of thrombosis and intimal hyperplasia (IH), which makes long-term lumen patency challengeable. Endothelial cells (ECs) form the inner endothelium layer, and are crucial for anti-coagulation and thrombogenesis. Thus, promoting in situendothelialization in vascular graft remodeling takes top priority, which requires recruitment of endothelia progenitor cells (EPCs), migration, adhesion, proliferation and activation of EPCs and ECs. Chemotaxis aimed at ligands on EPC surface can be utilized for EPC homing, while nanofibrous structure, biocompatible surface and cell-capturing molecules on graft surface can be applied for cell adhesion. Moreover, cell orientation can be regulated by topography of scaffold, and cell bioactivity can be modulated by growth factors and therapeutic genes. Additionally, surface modification can also reduce thrombogenesis, and some drug release can inhibit IH. Considering the influence of macrophages on ECs and smooth muscle cells (SMCs), scaffolds loaded with drugs that can promote M2 polarization are alternative strategies. In conclusion, the advanced strategies for enhanced long-term lumen patency of vascular grafts are summarized in this review. Strategies for recruitment of EPCs, adhesion, proliferation and activation of EPCs and ECs, anti-thrombogenesis, anti-IH, and immunomodulation are discussed. Ideal vascular grafts with appropriate surface modification, loading and fabrication strategies are required in further studies.

A multiobjective optimization (MOO) framework considering the dual objectives of the economy and the environment is presented in this work for the extended integration of interplant heat exchanger networks (HENs) and the shared utility system. Herein, the HENs of enterprises are integrated by allowing process streams to produce steam and using the steam as an intermediate fluid for cross-plant heat recovery, offsetting the utility steam supply in terms of interplant cooperative utilization of energy. The resultant new issues associated with steam generation (which and where), utilization (which and where), and the management of utility systems are addressed within the optimal design of the overall system by taking into account various possibilities. The framework is modeled as a mixed-integer nonlinear programming that accounts simultaneously for the minimum total annualized cost and the minimum environmental impact. A case with five specified scenarios is studied to demonstrate the benefit of structural extension and the conflict of the two objectives. Finally, the MOO problem is solved with Pareto solutions obtained, revealing the impact of network structure on the economy and the environment, which is more specific than a simple trade-off between energy consumption and equipment investment or a trade-off between different fuel sources.

Energy-integration methods for process systems such as Heat Exchanger Network Synthesis (HENS) and Work-Heat Exchanger Network Synthesis (WHENS) have been developed to promote energy conservation and reduce emissions in process systems. The proper integration of compression heat and HENS with multiple utilities instead of a single-level utility facilitates improving energy utilization. This paper introduces an extended superstructure-based model for the synthesis of a compression-heat-integrated heat exchanger network coupled with multiple utilities. The superstructure optimizes both heat exchange matches and the usage of high-, medium-, and low-pressure steam levels generated by the utility system. Compression heat for certain streams is also optimized to explore the interaction of compression work and utility consumption. A mixed-integer nonlinear programming model is established to simultaneously minimize the total annualized cost and exergy consumption. To demonstrate the feasibility of the proposed model, an example with two cases is investigated, indicating that compression heat can significantly improve heat recovery and energy efficiency.

Berberine (BBR), a well-known quaternary ammonium alkaloid, is recognized for its ability to prevent and alleviate metabolic disorders because of its anti-oxidative and anti-inflammatory properties. However, the underlying mechanisms of BBR to mitigate fatty liver hemorrhagic syndrome (FLHS) through the modulation of gut microbiota and their metabolism remained unclear. The results revealed that BBR ameliorates lipid metabolism disorder in high-energy and low-protein (HELP) diet-induced FLHS laying hens, as evidenced by improved liver function and lipid deposition of the liver, reduced blood lipids, and the expression of liver lipid synthesis-related factors. Moreover, BBR alleviated HELP diet-induced barrier dysfunction, increased microbial population, and dysregulated lipid metabolism in the ileum. BBR reshaped the HELP-perturbed gut microbiota, particularly declining the abundance of Desulfovibrio_pigerand elevating the abundance of Bacteroides_salanitronis_DSM_18170. Meanwhile, metabolomic profiling analysis revealed that BBR reshaped microbial metabolism and function, particularly by reducing the levels of hydrocinnamic acid, dehydroanonaine, and leucinic acid. Furthermore, fecal microbiota transplantation (FMT) experiments revealed that BBR-enriched gut microbiota alleviated hepatic lipid deposition and intestinal inflammation compared with those chicks that received a gut microbiota by HELP. Collectively, our study provided evidence that BBR effectively alleviated FLHS induced by HELP by reshaping the microbial and metabolic homeostasis within the liver-gut axis.

C10H16N12O6S2, triclinic, P1‾$P\overline{1}$ (no. 2), a= 7.6977(2) Å, b= 11.5353(3) Å, c= 11.7533(3) Å, α= 67.973(2)°, β= 87.916(2)°, γ= 88.347(2)°, V= 966.69(5) Å3, Z= 2, Rgt(F) = 0.0290, wRref(F2) = 0.0818, T = 170K.

Bone tissue engineering is considered as a promising pathway for bone regeneration and defect reconstruction, in which scaffolds play an important role. Zn alloy, which is a biodegradable metal material that has advantages of metallic and biodegradable characteristics, has its special features, especially the ideal degradation rate and acceptable biocompatibility, which make it worthy to be further investigated for medical applications. In this study, new biodegradable porous Zn alloy scaffolds with Ca–P coating were attempted to repair cranial bone defect, and in vitroand in vivoassays were conducted to evaluate its biocompatibility, osteo-inductivity, and osteo-conductivity. The results indicated that coated Zn alloy possessed good biocompatibility, with no cytotoxicity. It could also promote osteogenic differentiation and calcium deposition of rabbit BMSCs in vitro, and new bone formation around the scaffold in vivo. The biodegradable porous Zn alloy scaffold with Ca–P coating is considered to be promising in cranial bone defect repair.

Treatment with pour point depressant (PPD) can significantly improve the cold flowability of waxy crude oil, enabling the safe and efficient transportation of waxy crude oils through pipelines. It has been observed that the electrical properties of waxy oil, such as the dielectric constant, ζ-potential, etc., change upon PPD treatment. In a previous study, we reported that wax precipitation results in a significant change of impedance spectroscopy (IS) of a waxy oil, i.e., a second semicircle appears in the Nyquist diagram and becomes increasingly bigger with increasing amount of precipitated wax. In this study, we found that the addition of PPD may significantly reduce the second semicircle, and the more effective the PPD is, the more reduced the second semicircle will be. Equivalent circuit models suggest that the impedance characteristics of the liquid phase of wax-in-oil suspension change little with PPD addition, but the capacitance of wax particles increases and the resistance of wax particles decreases significantly. A positive correlation between the viscosity reduction and the reduction of resistance of wax particles caused by PPD is discovered. After PPD treatment, the polar functional groups in PPD molecules potentially induce charge on wax particles as they precipitate, causing the relationship between the viscosity and conductivity to approach the fractional Walden rule. This work explains the reason for the improvement of flowability upon PPD addition from a perspective of IS, which provides some new proofs to understanding the functional mechanism of PPD.

Purpose: Virtual surgery system can provide us a realistic and immersive training environment, in which haptic force-feedback gives operators ‘touching feeling.’ Appropriate deformation models of soft and hard tissues are required for the achievement of real-time haptic feedback. To improve accuracy of modeling and haptic feedback simulation for maxillofacial virtual surgery, mechanical characteristics of soft and hard tissues should be explored. Methods: Craniofacial soft tissues from one male and female cadavers were divided into two layers: skin and muscle. Maxillofacial tissues were divided into frontal, chin, temporalis, masseter regions. Insertion and cutting process were conducted using VMX42 5-axis linkage system and recorded by piezoelectric dynamometer. Maximum stiffness values were analyzed, and insertion curves before puncture were fitted using a polynomial model. Elasticity modulus and hardness of maxillofacial hard tissues were measured and analyzed using Berkovich nanoindentation. Results: Tissues in different maxillofacial regions, as well as from different layers (skin and muscle), displayed various mechanical performance. Maximum stiffness values and cutting force of soft tissues in male and female had significant difference. The third-order polynomial was demonstrated to fit the insertion curves well before puncture. Furthermore, elasticity modulus and hardness of enamel were significantly greater than that of zygoma, maxilla and mandible. Conclusion: Mechanical properties of hard tissues are relatively stable, which can be applied in virtual surgery system for physical model construction. Insertion model and cutting force for soft tissues are meaningful and applicable and can be utilized to promote the accuracy of response for haptic feedback sensations.

In this article, a novel simulation–optimization method is proposed for the simultaneous design of a heat-integrated coal-to-SNG/MeOH (CTSM) polygeneration process, aiming at exergy efficiency enhancement. The genetic algorithm is adopted to simultaneously optimize the presented polygeneration process, which combines the key reaction units based on rigorous kinetic modeling and simulation with a waste heat recovery steam cycle (WHRSC). A heat integration approach that considers variable stream conditions is introduced to connect CTSM and WHRSC. In developing this approach, an extended Duran–Grossmann (D–G) model is established, which incorporates the isothermal phase change and nonisothermal phase change. The interaction mechanism between process synthesis and heat integration is further explored. Compared with the base case obtained by a sequential method, the presented method yields a 2.22 percentage point increase in the overall exergy efficiency and a 44.05% improvement of power generation. In this sense, the utility consumption in the polygeneration process can be sharply reduced and even achieve zero hot utility consumption. The corresponding heat exchanger network is determined that consists of 56 heat exchangers and 7 coolers with a total area of 93 763 m2. Furthermore, the interaction among different process units reveals that process synthesis has a stronger effect on heat integration.

A heat exchanger network (HEN) plays an important role in the chemical process industry owing to its significant effect in energy recovery. A compression–absorption cascade refrigeration system (CACRS) is a promising technique for energy saving, which is able to utilize the process waste heat to generate cooling energy in different grades. The integrated design and optimization of HEN and CACRS can further improve waste-heat utilization and energy conversion efficiency. However, it is still very challenging to achieve a good integrating performance. To address the issue, an optimization-based method is proposed here that enables the simultaneous determination of the structure of HEN and the operating condition of CACRS. First, an improved superstructure is presented, considering various possibilities in matching, coupling, and system configurations. Based on the superstructure, a mixed-integer non-linear programming model is formulated for optimizing both the network structure and the operating variables, with the objective of minimizing the total annualized cost. Therein, the thermodynamic model of CACRS is included to obtain the optimal CACRS operating condition automatically. Finally, two cases are investigated to illustrate the advantage of the proposed method in improving economic performance and energy conversion efficiency.

Synthesis of heat exchanger networks including expansion process is a complex task due to the involvement of both heat and work. A stream that expands through expanders can produce work and cold load, while expansion through valves barely affects heat integration. In addition, expansion through expanders at higher temperature produces more work, but consumes more hot utility. Therefore, there is a need to weigh work production and heat consumption. To this end, an enhanced stage-wise superstructure is proposed that involves synchronous optimization of expander/valve placement and heat integration for each pressure-change sub-stream in stages. A mixed-integer nonlinear programming (MINLP) model is established for synthesizing sub and above-ambient heat exchanger networks with multi-stream expansion, which explicitly considers the optimized selection of end-heaters and end-coolers to adjust temperature requirement. Our proposed method can commendably achieve the optimal selection of expanders and valves in a bid for minimizing exergy consumption and total annual cost. Four example studies are conducted with two distinct objective function (minimization of exergy consumption and total annual cost, respectively) to illustrate the feasibility and efficacy of the proposed method.

Intermedium agents play an important role in indirect interplant heat integration. Each of them has a unique performance in heat recovery, however seldom conjunctively employed, which simplifies the problem but limits the extent of heat recovery. Thus, in order to fully exploit the potential of cascade heat recovery across plants, this work presents an optimization-based method to perform the automatic selection and arrangement of intermedium fluids in their integration with each single plant. A total site heat exchanger network superstructure model of possible configurations combining the allocation of medium streams (multiple agents and multiple circles) across plants and the heat exchanges between intermediate fluids and inner-plant process streams is proposed. For single-period concerns, the generalized model is formulated into a mixed-integer nonlinear programming problem to perform the network optimization at minimum total annualized cost target. Beyond this, the multiperiod problem is further studied to accommodate the time-related variations in the long operating horizon of an industrial park, and a robust network is achieved with updated modeling. Finally, a numerical case is illustrated in several scenarios; the significant drop in network cost shows the effectiveness of the method and the extended application of the method in a multiperiod design is also presented.