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AbstractIn-vessel retention through external reactor vessel cooling (IVR-ERVC) is a strategy used to respond to nuclear reactor accidents. One of the key performance indicators determining its feasibility is critical heat flux (CHF). Our focus is on simulating real-world scenarios through surface pool boiling to improve the implementation of the IVR-ERVC strategy with hybrid nanofluids. Two groups of TiO2/COOH-CNTs hybrid nanofluids were prepared: group 1 with different concentrations at the same proportion and group 2 with different proportions at the same total concentration.Researchers compared the improvement of the two groups’ CHF and heat transfer coefficient (HTC), and analyzed the potential mechanism of heat transfer enhancement through roughness of surface, hydrophilicity, and scanning electron microscopy observations. The results showed that a mass concentration of 8 mg:8 mg per liter exhibited the best heat transfer performance, with a CHF enhancement up to 28.21% and an improvement in HTC as well. Meanwhile, correlations between alterations in surface roughness, hydrophilicity, and enhancements in CHF were observed. Finally, by detecting the deposition surface, the possible mechanism of TiO2/COOH-CNTs hybrid nanofluids in enhancing heat transfer was inferred. [ABSTRACT FROM AUTHOR]

• Hydroxyapatite (HAP) composite paper with biocompatibility and hygroscopicity was prepared. • HAP composite paper has better hygroscopic and triboelectric properties than pure paper, making it more suitable for wearable sensing applications. • The HAP composite paper-based triboelectric nanogenerator can detect and distinguish different joint movements. • Hemostatic and disposable HAP composite paper can be degraded in the natural environment without harm. Wearable triboelectric nanogenerators (TENGs) have attracted considerable attention in the field of self-powered sensors that can be worn on the skin directly without packaging because of their breathability, conformability, and sensitivity to collect biomechanical energy. However, high humidity on the skin can affect the wearable TENG output performance, substantially affecting the sensor performance and stability. When worn for a long time, humidity can even cause skin inflammation. Thus, for a wearable TENG, moisture control and biocompatibility are also key factors that need to be addressed. Herein, we report a hygroscopic and biocompatible paper-based TENG using a hydroxyapatite (HAP) mineral coating to enhance the paper fiber. The mineral coating can maintain the surface of the paper fiber, which will not cause large external deformation of the paper fiber under a force, avoid squeezing out excess water, and keep the friction surface dry, avoiding humidity affecting the output performance. Without interfering with the performance of the TENG, the maximum water absorption of the HAP composite paper is ∼8 μL. The HAP composite paper–based TENG (4 cm2) has an open-circuit voltage and short-circuit current 5.8 times and 4.2 times that of pure paper, respectively, and can obtain 80.4 mW/m2 output and directly light 117 LEDs. At relative humidity values of 25.7 %, 43.1 %, and 58.8 %, the performance retained the peak values of 80.2 %, 68 %, and 63.7 %, respectively. Even at a high relative humidity of 71.7 %, the triboelectric performance of HAP composite paper is retained 59.3 %, and the stability under humidity is better than that of pure paper (45.6 %). In addition, the mineral paper can even work with tissue fluid and output performance decreases by 43.8 %. The mineral-enhanced paper TENG with high power generation performance, hygroscopicity, biocompatibility, and degradability provides a new perspective for disposable wearable sensors, even in medical treatment. [ABSTRACT FROM AUTHOR]

• In this paper, we report the corrosion inhibition of amino acid imidazole ionic liquids ([CyVIm][AA]ILs) on mild steel in neutral media, which has not been studied before. • In addition, the corrosion inhibition performance of [CyVIm][AA]ILs in neutral media was evaluated comprehensively by a combination of experiments and simulations as well as an in-depth investigation of the corrosion inhibition mechanism. The corrosion inhibition properties of three amino acid imidazole ionic liquids ([CyVIm][AA]) as corrosion inhibitors for mild steel in a 3.5 wt% NaCl corrosion medium were evaluated by electrochemical measurements. The polarization experiments show that [CyVIm][AA] influences anode reaction processes, demonstrating that [CyVIm][AA] is an anodic inhibitor type corrosion inhibitor. [CyVIm]Try outperforms [CyVIm]His and [CyVIm]Pro in terms of corrosion inhibition. The results of surface analysis and quantum chemical calculations show that [CyVIm]Try can form a protective film on the surface of mild steel and inhibit surface corrosion. Furthermore, by applying molecular dynamics simulations, after investigating the corrosion inhibitor adsorption trends on the Fe (1 1 0) surface, the interaction order between the molecular framework of the Fe corrosion inhibitor and the Fe (1 1 0) surface for entanglement was determined. According to the radial distribution function, the corrosion inhibitor adsorption mode on the metal surface is composite adsorption with chemisorption as the major mode and physical adsorption as the secondary mode. [ABSTRACT FROM AUTHOR]

If a highly elastic ball is thrown into the space between two parallel matte plates, under some circumstances, the ball might be projected back in the opposite direction after bounding a few times. In this paper, a theoretical model, which describes the transformation of the ball's centroid velocity and angular velocity before and after a collision, as well as its motion in the air between two collisions, is established and then verified by experiments. In addition, the coefficient of restitution between the ball and the plates are fitted. Numerical simulations were performed to discuss the conditions under which the ball would rebound back and its various rebounding modes that might exist. [ABSTRACT FROM AUTHOR]

• A co-generation system consisting of Allam cycle and heat pump is proposed. • The latent heat of working fluid in Allam cycle is recovered for space heating. • The proposed system is more efficient and economical with nearly zero emissions. • The proposed system is more suitable for co-generation in cold regions. Allam cycle is known as a promising alternative cycle for power generation, which combines the advantage of both oxygen-enriched combustion technology and supercritical carbon dioxide technology. In this study, an integrated energy system consisting of an Allam cycle and a heat pump is proposed to co-generate power and heat. The heat of carbon dioxide in the compression train of the Allam cycle is recovered by the heat pump system, which is used for space heating. The techno-economic and environmental performances of the co-generation system are analyzed and compared with those of the single systems. The results show that the net electrical efficiency of the Allam cycle is improved by 1.56 %, and the coefficient of performance of the heat pump in the combined system is increased by 42.02 %. The lowest and highest investment-increment payback periods are 0.26 and 5.80 years, which indicates the proposed integrated system is economically feasible. Meanwhile, the sensitivity analysis of key economic parameters is also conducted. Finally, the carbon emission of different generation configurations are compared and the results indicate that the integration of the heat pump with the Allam cycle can effectively reduce system carbon emission. The proposed concept provides a new approach to efficient utilization of the heat from the carbon dioxide mixture cooling process for heat and power generation with nearly zero emission, and it would be a better choice for cold regions. [ABSTRACT FROM AUTHOR]

Sirtuins are a family of NAD+‐dependent deacetylases that regulate some important biological processes, including lipid metabolism and autophagy, through their deacetylase function. Autophagy is a new discovery in the field of lipid metabolism, which may provide a new idea for the regulation of lipid metabolism. There are many tandem parts in the regulation process of lipid metabolism and autophagy of sirtuins protein family. This paper summarized these tandem parts and proposed the possibility of sirtuins regulating lipid autophagy, as well as the interaction and synergy between sirtuins protein family. Currently, some natural drugs have been reported to affect metabolism by regulating sirtuins, some of which regulate autophagy by targeting sirtuins. Significance statement: Lipid metabolism disorders, such as diabetes and atherosclerosis, have seriously harmed human health and caused economic and social burden. The role of sirtuins protein family in aging has been widely concerned, but they also show value in the regulation of lipid metabolism. Autophagy is a new discovery in the field of lipid metabolism, which may provide a new idea for the regulation of lipid metabolism. There are many tandem parts in the regulation process of lipid metabolism and autophagy of sirtuins protein family. This paper summarized these tandem parts and proposed the possibility of sirtuins regulating lipid autophagy, as well as the interaction and synergy between sirtuins protein family. [ABSTRACT FROM AUTHOR]

The corrosion inhibition performance of three choline amino acid ionic liquids ([Ch][AA]ILs) for mild steel in 1 M HCl solution was evaluated by electrochemical analysis, gravimetric measurement, and surface morphological characterization in the temperature range of 298–328 K in this paper. The results of the polarization experiments show that [Ch][AA]ILs affect the cathode and anode reaction processes, proving that [Ch][AA]ILs are mixed corrosion inhibitors. Choline phenylalanine ionic liquids ([Ch][Phe]) exhibit the highest corrosion prevention efficiency among the three chosen corrosion inhibitors, as proven by SEM/EDS scanning, XPS analysis, and molecular dynamics simulation. The values of standard free energy of adsorption Δ G ads range between − 20 kJ·mol-1 and − 40 kJ·mol-1, showing that inhibitor molecule adsorption on the metal surface involves both physical and chemical adsorption. According to the results of XPS research and quantum chemical calculations, the adsorption of corrosion inhibitor molecules on the metal surface is strongly related to the anions. The corrosion inhibitor molecules form a thick monolayer adsorption layer on the metal surface, preventing metal-corrosive media interaction. The molecular dynamics simulation findings reveal that the corrosion inhibitor molecules replace the solvent water or any other ions pre-adsorbed on the metal surface during the adsorption process, protecting the metal from corrosion. [Display omitted] [ABSTRACT FROM AUTHOR]

In this paper, the rheological properties, drag reduction properties, and flow field characteristics of hydrolyzed polyacrylamide (HPAM) solution, xanthan gum (XG) solution, and HPAM–XG composite solution were analyzed to explore the synergistic effect of flexible and rigid polymer. The experimental results show that the viscoelasticity and shear thinning of the composite solution are significantly enhanced compared with single‐component solution, which indicates that the rigid XG has an effect on the viscoelasticity of the flexible HPAM solution. Compared with the single‐component solution, the drag reduction rate of HPAM–XG composite solution is higher, and the mean flow field of HPAM–XG composite solution changes less after being sheared for 300 minutes, which means that not only the drag reduction effect of composite solution is better, but also the shear resistance. Compared with single‐component solution, the mean velocity distribution of the composite solution moves upwards most obviously in the logarithmic layer, the peak of velocity fluctuation in the main flow direction of composite solution is higher, the suppression degree of normal velocity fluctuation is deepened, and the corresponding vorticity intensity is also reduced. These changes in the flow field characteristics explain the reason for the drag reduction gain of the composite solution. [ABSTRACT FROM AUTHOR]

The tight association between malnutrition and gut microbiota (GM) dysbiosis enables microbiota-targeting intervention to be a promising strategy. Thus, we used a malnourished pig model to investigate the host response and GM alterations under different diet supplementation strategies. Pigs at age of 4 weeks were fed with pure maize diet to induce malnutrition symptoms, and followed by continuous feeding with maize (Maize, n = 8) or re-feeding using either corn-soy-blend (CSB+, n = 10) or millet-soy-blend based (MSB+, n = 10) supplementary food for 3 weeks. Meanwhile, 8 pigs were fed on a standard formulated ration as control (Ref). The effect of nutritional supplementation was assessed by the growth status, blood chemistry, gastrointestinal pathology, mucosal microbiota composition and colon production of short-chain fatty acids. Compared with purely maize-fed pigs, both CSB+ and MSB+ elevated the concentrations of total protein and globulin in blood. These pigs still showed most malnutrition symptoms after the food intervention period. MSB+ had superior influence on the GM development, exhibiting better performance in both structural and functional aspects. MSB+ pigs were colonized by less Proteobacteria but more Bacteroidetes, Firmicutes and Lachnospira spp. Pearson's correlation analysis indicated a strong correlation between the abundance of mucosal e.g., Faecalibacterium and Lachnospira spp. and body weight, crown-rump length and total serum protein. In conclusion, the malnutrition symptoms were accompanied by an aberrant GM, and millet-based nutritional supplementation showed promising potentials to restore the reduced GM diversity implicated in pig malnutrition. [ABSTRACT FROM AUTHOR]

To address climate change, the Chinese government has committed to achieving carbon peaking by 2030. Projecting the wind power and photovoltaic installed capacity is essential for China's low carbon transition as these renewables have been widely recognized as the major energy sources in future. This study proposes a long-term strategic planning approach for wind power and photovoltaic by simulating multiple policies and market scenarios for the national-level energy transitions and incorporating the feedback effects of market development on technology readiness level. The proposed approach simulates the national energy consumption and energy mix under various transition scenarios based on the Long-range Energy Alternatives Planning System (LEAP). The dynamics of market development, technology readiness level, and future renewable costs are further incorporated into a nonlinear optimization model to generate economically optimal planning solutions for wind power and photovoltaic under different policy and market scenarios. Valuable insights are obtained from three perspectives, i.e., (1) the economic and emission reduction co-benefits under different scenarios, (2) the evolution of the Levelized Cost of Energy, and (3) the impact on the transition of power sector. In particular, the simulation and optimization results reveal that appropriate acceleration of wind power and photovoltaic development can promote technology readiness level, reduce overall transition costs, and effectively reduce the peak value of emissions. The maximum peak reduction in carbon dioxide emissions is 16.06%, and the maximum cumulative reduction in carbon dioxide emissions is 14.54%. The total project cost can be reduced by a maximum of 3.23%. Thus, more active supporting policies for renewables can further enhance long-term economic and environmental co-benefits under current conditions. [Display omitted] • Quantify the market's dynamic feedback on renewable costs through learning curves. • Incorporate technology readiness level into energy long-term renewable planning. • Optimize long-term renewable planning for different policy and market conditions. • Active wind and solar power investments now offer larger co-benefits in future. • CO 2 peak down 16.06% and the cumulative CO 2 reduction 14.54%. [ABSTRACT FROM AUTHOR]

Lactobacillus salivarius Ren (LsR) (CGMCC No. 3606) is a probiotic strain that was isolated from the feces of a healthy centenarian living in Bama, Guangxi, China. Previous studies have shown that this strain decreases 4-nitroquinoline 1-oxide (4-NQO)-induced genotoxicity in vitro . It also suppresses 4-NQO-induced oral carcinogenesis and 1,2-dimethylhydrazine (DMH)-induced colorectal carcinogenesis, and therefore may be used as an adjuvant therapeutic agent for cancer. Here, we report the complete genome sequence of LsR that consists of a circular chromosome of 1751,565 bp and two plasmids (pR1, 176,951 bp; pR2, 49,848 bp). [ABSTRACT FROM AUTHOR]

Weak acid resistance limits the application of Bifidobacteria as a probiotic in food. The acid tolerance response (ATR), caused by pre-stressing cells at a sublethal pH, could improve the acid resistance of Bifidobacteria to subsequent acid stress. In this study, we used Bifidobacterium longum sub. longum BBMN68 to investigate the effect of the ATR on the acid stress response (ASR), and compared the difference between the ATR and the ASR by analyzing the two-dimensional-PAGE protein profiles and performing physiological tests. The results revealed that a greater abundance of proteins involved in carbohydrate metabolism and protein protection was present after the ASR than after the ATR in Bifidobacterium. Pre-stressing cells increased the abundance of proteins involved in energy production, amino acid metabolism, and peptidoglycan synthesis during the ASR of Bifidobacterium. Moreover, after the ASR, the content of ATP, NH3, thiols, and peptidoglycan, the activity of H+-ATPase, and the maintenance of the intracellular pH in the pre-stressed Bifidobacterium cells was significantly higher than in the uninduced cells. These results provide the first explanation as to why the resistance of Bifidobacterium to acid stress improved after pre-stressing. [ABSTRACT FROM AUTHOR]

Background & Aims The liver's response to injury is fibrosis, and when chronic, cirrhosis. Age is a critical factor impacting many immune-mediated processes, potentially including the liver's wounding response to injury. Methods The effects of age on acute and chronic liver injury were evaluated using a carbon tetrachloride model in mice. Lymphocyte and macrophage populations were assessed by flow cytometry and immunohistochemical analysis. Results Acute liver injury was greater in 18-month-old (old) mice than in 9-month-old (middle-aged) mice as judged by changes in aminotransferases. Similarly, livers of 18-month-old mice had a significantly greater fibrogenic response to injury than did livers of 9-month-old mice after chronic injury (assessed by col1α1 mRNA expression, morphometric analysis and hydroxyproline measurement). Interestingly, livers from young mice (6 weeks old) also exhibited an increase in fibrogenesis compared to 9-month-old mice, albeit not to the same degree as in old mice. Consistent with a role for macrophages in fibrogenesis, the number of liver macrophages in young and 9-month-old mice increased, while in chronically injured livers of 18-month-old mice, the number of macrophages was reduced, and was less than in the livers of young and 9-month-old injured livers. Conclusions Our data indicate that the fibrogenic response to injury varies substantially with age, and moreover that macrophage recruitment and dynamics may be an important component in differential age-associated fibrotic disease. [ABSTRACT FROM AUTHOR]

Background: The purpose of this study was to compare simple visual grading of perfusion CT (PCT) maps to a more quantitative, threshold-based interpretation of PCT parameters in the characterization of presence and severity of vasospasm. Methods: Thirty-three patients with acute subarachnoid hemorrhage were enrolled in a prospective study and underwent a total of 40 paired PCT and digital subtraction angiography (DSA) examinations. A neuroradiologist and a neurologist reviewed the PCT mean transit time (MTT), cerebral blood flow (CBF), and cerebral blood volume maps independently; they evaluated five anatomical regions (frontal, temporal, parietal, occipital/thalami, and basal ganglia/insula) and graded them for abnormality (0 if normal, 1 if abnormal in <50% of the region, and 2 if abnormal in ≥50% of the region). A third neuroradiologist blinded to the PCT results reviewed the DSA examinations and assessed 19 segments for the presence or absence of vasospasm. Correlation between PCT and DSA scores was assessed, as well as the sensitivity and specificity of PCT compared to DSA used as a gold standard. Results: MTT (R2 = 0.939) and CBF (R2 = 0.907) scores correlated best with DSA scores (p < 0.001). MTT scoring had a sensitivity of 92% and a specificity of 86% compared to DSA; CBF scoring had a sensitivity of 75% and a specificity of 95%. The interobserver agreement between neuroradiologist and neurologist was found to have kappa = 0.789 for MTT and 0.658 for CBF. Conclusion: We propose a user-friendly visual grading system for PCT maps in patients with suspected vasospasm. This visual approach compares favorably to the results of DSA. Sensitive MTT maps should be used for screening, and specific CBF maps for confirmation of vasospasm. Copyright © 2008 S. Karger AG, Basel [ABSTRACT FROM AUTHOR]

Purpose: To evaluate the accuracy of multidetector-row CT angiography (CTA) for the diagnosis of large-vessel vasospasm following subarachnoid hemorrhage by comparison to digital subtraction angiography (DSA). Methods: Thirty-three patients with acute subarachnoid hemorrhage were enrolled in a prospective study and underwent a total of 40 CTA and DSA examinations within 24 h of each other. Two neuroradiologists reviewed the CTA examinations independently. A third neuroradiologist blinded to the CTA results reviewed the DSA examinations. In each patient, for both techniques, 23 arterial segments were evaluated for their degree of narrowing; the reviewers were asked to attribute every narrowing to ‘vasospasm’ or ‘hypoplasia’. Agreement between CTA and DSA for the degree of narrowing, and agreement between the two CTA readers, were calculated using weighted κ-coefficients. Sensitivity, specificity, accuracy, positive and negative predictive value (NPV) of CTA to detect large-vessel vasospasm were calculated considering DSA as the gold standard. Results: Substantial correlation (κ = 0.638) was found between CTA and DSA for the detection of arterial narrowing. Interobserver agreement between the two CTA reviewers for the degree of luminal narrowing was substantial (κ = 0.712).CTA was 87% accurate for the diagnosis of large-vessel vasospasm; the NPV of CTA was 95%. CTA was more accurate, and interobserver agreement higher, for the proximal arterial segments (basilar and vertebral arteries) than for the distal ones (P2 segments). Using CTA as a screening modality, 83% of unnecessary DSA would have been avoided. Conclusion: Compared to the gold standard of DSA, CTA is accurate for the detection of large-vessel vasospasm, and has a very high NPV. Copyright © 2007 S. Karger AG, Basel [ABSTRACT FROM AUTHOR]

Objective: To systematically evaluate the accuracy of noncontrast computed tomography (NCT), perfusion computed tomography (PCT), and computed tomographic angiography (CTA) in determining site of occlusion, infarct core, salvageable brain tissue, and collateral flow in a large series of patients suspected of acute stroke. Methods: We retrospectively identified all consecutive patients with signs and symptoms suggesting hemispheric stroke of < 48 hours in duration who were evaluated on admission by NCT, PCT, and CTA, and underwent a follow-up CT/CTA or magnetic resonance imaging (MRI) and magnetic resonance angiography (MRA) within 6 months of initial imaging. Two neuroradiologists evaluated NCT for hypodensity, PCT for infarct core and salvageable brain tissue, and CTA source images and maximal intensity projections for site of occlusion, infarct core, and collateral flow. Follow-up CTA and MRA were assessed for persistent arterial occlusion or recanalization. Follow-up CT and MRI were reviewed for final infarct location and volume, and used as a gold standard to calculate sensitivity (SE) and specificity (SP) of initial imaging. Results: A total of 113 patients were considered for analysis, including 55 patients with a final diagnosis of stroke. CTA source images were the most accurate technique in the detection of the site of occlusion (SE = 95%; SP = 100%). Decreased cerebral blood volume on PCT was the most accurate predictor of final infarct volume (SE = 80%; SP = 97%), Increased mean transit time on PCT was predictive of the tissue at risk for infarction in patients with persistent arterial occlusion. CTA maximal intensity projections was the best technique to quantify the degree of collateral circulation. Interpretation: The most accurate assessment of the site of occlusion, infarct core, salvageable brain tissue, and collateral circulation in patients suspected of acute stroke is afforded by a combination of PCT and CTA. [ABSTRACT FROM AUTHOR]

Streptococcus thermophilus MN-BM-A01 (ST MN-BM-A01) (CGMCC No. 11383) was a strain isolated from Yogurt Block in Gansu, China. The yogurt fermented with this strain has good flavor, acidity, and viscosity. Moreover, ST MN-BM-A01 could produce a high level of EPS which can confer the yogurt with improved rheological properties. We reported the complete genome sequence of ST MN-BM-A01 that contains 1,876,516 bp encoding 1704 coding sequences (CDSs), 67 tRNA genes and 6 rRNA operons. The genomic sequence indicated that this strain included a 35.3-kb gene cluster involved in EPS biosynthesis. [ABSTRACT FROM AUTHOR]

Lactobaillus paracasei L9 (CGMCC No. 9800) is a new strain with probiotic properties originating from healthy human intestine. Previous studies evidenced that the strain regulates immune modulation and contributes to the production of high amounts of lactic acid. The genome of L. paracasei L9 contains a circular 3076,437-bp chromosome, encoding 3044 CDSs, 15 rRNA genes and 59 tRNA genes. [ABSTRACT FROM AUTHOR]

Bifidobacterium animalis subsp. lactis A6 (BAA6) (CGMCC No. 9273) was a probiotic strain isolated from the feces of a centenarian. Previous study showed that BAA6 had high acid resistance to low pH which is a critical factor influencing its healthy benefits. Elaborating the stress resistant mechanisms of bifidobacteria is important to extensively exploit this probiotic. Here, we reported the complete genome sequence of BAA6 that contains 1,958,651 bp encoding 1622 CDSs, 16 rRNA genes, 52 tRNA genes. [ABSTRACT FROM AUTHOR]