| 1. |
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| 2. |
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- 2019
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Tidskriftsartikel (refereegranskat)
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| 3. |
- Agirre, Jon, et al.
(författare)
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The CCP4 suite: integrative software for macromolecular crystallography
- 2023
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Ingår i: Acta Crystallographica Section D. - : INT UNION CRYSTALLOGRAPHY. - 2059-7983. ; 79, s. 449-461
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Tidskriftsartikel (refereegranskat)abstract
- The Collaborative Computational Project No. 4 (CCP4) is a UK-led international collective with a mission to develop, test, distribute and promote software for macromolecular crystallography. The CCP4 suite is a multiplatform collection of programs brought together by familiar execution routines, a set of common libraries and graphical interfaces. The CCP4 suite has experienced several considerable changes since its last reference article, involving new infrastructure, original programs and graphical interfaces. This article, which is intended as a general literature citation for the use of the CCP4 software suite in structure determination, will guide the reader through such transformations, offering a general overview of the new features and outlining future developments. As such, it aims to highlight the individual programs that comprise the suite and to provide the latest references to them for perusal by crystallographers around the world.
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| 4. |
- Chen, Fu qiang, et al.
(författare)
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Thermo-mechanical stress and fatigue damage analysis on multi-stage high pressure reducing valve
- 2017
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Ingår i: Annals of Nuclear Energy. - : Elsevier BV. - 0306-4549. ; 110, s. 753-767
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Tidskriftsartikel (refereegranskat)abstract
- A multi-stage high pressure reducing valve (MSHPRV) is proposed. It can achieve a multi-stage pressure reducing way. Valve failure mainly occurs under high pressure and high temperature conditions, thus it is necessary to investigate the strength of MSHPRV under those complex conditions. In this paper, the mathematical model of MSHPRV is established and Computational Fluid Dynamics (CFD) method is employed to simulate its flow fields and thermo-mechanical stress. Next, the stress of MSHPRV under different opening time and the fatigue damage of MSHPRV under different valve openings are studied. Finally, two changes are provided on geometry of MSHPRV and the geometrical factors are optimized. The results show that, the radial direction from inner wall to outer wall is the main heat transfer direction for valve body. At opening time 50 s, the working condition of MSHPRV is dangerous condition. Meanwhile, the maximum value of thermal stress is 487 MPa, which is located at the upper end face of valve chamber region B3. There is a lag effect of stress distribution with respect to temperature distribution. The combined stress of valve body is composed of thermal stress and mechanical stress, in which thermal stress holds the dominant position. Moreover, with the increasing of valve opening, the fatigue damage of valve body increases correspondingly. It can be concluded that MSHPRV can cope with complex conditions like high pressure and high temperature. In the optimization design of MSHPRV, it can be found that the best strength of MSHPRV is achieved with such geometrical factors as angle 15, diameter 4 mm and 2 stage plates. Besides, radian design as the improved structure is recommended. This work can benefit the further research work on the regulation performance and safe operation of high pressure reducing valve.
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| 5. |
- Chen, Ke-Ling, et al.
(författare)
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Effects of Tocilizumab on Experimental Severe Acute Pancreatitis and Associated Acute Lung Injury
- 2016
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Ingår i: Critical Care Medicine. - : LIPPINCOTT WILLIAMS & WILKINS. - 0090-3493 .- 1530-0293. ; 44:8, s. E664-E677
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Tidskriftsartikel (refereegranskat)abstract
- Objective: To examine the therapeutic effects of tocilizumab, an antibody against interleukin-6 receptor, on experimental severe acute pancreatitis and associated acute lung injury. The optimal dose of tocilizumab and the activation of interleukin-6 inflammatory signaling were also investigated. Design: Randomized experiment. Setting: Research laboratory at a university hospital. Subject: Experimental severe acute pancreatitis in rats. Interventions: Severe acute pancreatitis was induced by retrograde injection of sodium taurocholate (50 mg/kg) into the biliopancreatic duct. In dose-study, rats were administered with different doses of tocilizumab (1, 2, 4, 8, and 16 mg/kg) through the tail vein after severe acute pancreatitis induction. In safety-study, rats without severe acute pancreatitis induction were treated with high doses of tocilizumab (8, 16, 32, and 64 mg/kg). Serum and tissue samples of rats in time-study were collected for biomolecular and histologic evaluations at different time points (2, 6, 12, 18, and 24 hr). Measurements and Main Results: 1) Under the administration of tocilizumab, histopathological scores of pancreas and lung were decreased, and severity parameters related to severe acute pancreatitis and associated lung injury, including serum amylase, C-reactive protein, lung surfactant protein level, and myeloperoxidase activity, were all significant alleviated in rat models. 2) Dose-study demonstrated that 2 mg/kg tocilizumab was the optimal treatment dose. 3) Basing on multi-organ pathologic evaluation, physiological and biochemical data, no adverse effect and toxicity of tocilizumab were observed in safety-study. 4) Pancreatic nuclear factor-kappa B and signal transducer and activator of transcription 3 were deactivated, and the serum chemokine (C-X-C motif) ligand 1 was down-regulated after tocilizumab administration. Conclusions: Our study demonstrated tocilizumab, as a marketed drug commonly used for immune-mediated diseases, was safe and effective for the treatment of experimental severe acute pancreatitis and associated acute lung injury. Our findings provide experimental evidences for potential clinical application of tocilizumab in severe acute pancreatitis and associated complications.
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| 6. |
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| 7. |
- He, Xiaoyu, et al.
(författare)
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Dual-optimization strategy engineered Ti-based metal-organic framework with Fe active sites for highly-selective CO2 photoreduction to formic acid
- 2023
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Ingår i: Applied Catalysis B. - : Elsevier BV. - 0926-3373 .- 1873-3883. ; 327
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Tidskriftsartikel (refereegranskat)abstract
- Increasing CO2 conversion efficiency over metal-organic framework (MOF) based photocatalysts is of great significance to promote the carbon capture and utilization. In this work, a dual-benefit design strategy is deployed in the synthesis of a new two-dimensional Fe/Ti-BPDC MOF photocatalyst with atomically dispersed Fe sites. This catalyst demonstrated an excellent catalytic performance in the visible-light-driven CO2 conversion to HCOOH, achieving a high yield of 703.9 μmol g-1 h-1 at a selectivity greater than 99.7%. This is attributed to the ‘dual-optimization’ achieved by this catalyst to sustain the supply of photogenerated electrons and to effectively activate CO2. Specifically, the Fe/Ti-BPDC catalyst provides a high proportion of effective photogenerated electrons for the CO2 photocatalysis process via a unique electron transfer mechanism. Meanwhile, the strong O/Fe affinity between CO2 and atomically dispersed Fe active sites not only enables a fast CO2 activation, but also dictates the intermediate reaction pathways towards high HCOOH selectivity.
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| 8. |
- Li, Kai, et al.
(författare)
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Metal thermopile infrared detector with vertical graphene
- 2023
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Ingår i: Wuli Xuebao/Acta Physica Sinica. - : Acta Physica Sinica, Chinese Physical Society and Institute of Physics, Chinese Academy of Sciences. - 1000-3290. ; 72:3
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Tidskriftsartikel (refereegranskat)abstract
- Thermopile infrared detector is a kind of detector device mainly composed of thermocouple as the basic unit. Because of its simple principle, no need of cooling equipment, and other advantages, it has been widely used in various fields of production and life. However, the absorption rates of the materials in conventional thermopile devices are poor, and the majority of them are incompatible with microfabrication methods. In this work, a metal thermopile infrared detector with vertical graphene (VG) is designed and fabricated. The VG is grown via plasma enhanced chemical vapor deposition, and retained at the device’s thermal ends to provide the thermopile IR detector’s wideband and high response characteristics. The detector achieves a room temperature responsivity reaching a value as high as 1.53 V/W at 792 nm, which can increase the response results about 28 times and reduce the response time to 0.8 ms compared with the thermopile detector without VG. After systematically measuring the response results, it is finally found that there are three main mechanisms responsible for the response on the composite device. The first one is the response generated by the metal thermopile itself alone. The second one is the response increased eventually by the contribution of VG covered at the metal thermal junction that expands the temperature difference. The last one is the response generated by the temperature gradient existing inside the VG on the surface of the device after the absorption of heat. The portion of each partial response mechanism in the total response is also analyzed, providing a new reference direction for analyzing the response generation mechanism of thermopile detectors with other absorbing materials. The process is compatible with the microfabrication, while the device performance is enhanced and suitable for mass production. Furthermore, by utilizing the surface plasmon resonance to combine VG with metal nanoparticles, the material’ s light absorption is found to be enhanced significantly under the same conditions, and the resulting thermal voltage can be increased to 6 times. The results indicate that VG promises to possess practical applications, in many fields such as photoelectric sensing and power production devices. This technology provides a new method to manufacture high-performance thermopile infrared detectors and other sensor devices.
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| 9. |
- Liu, Fei, et al.
(författare)
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Evolution of particle size distribution and water content for oily particles in machining workshops
- 2024
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Ingår i: Journal of Building Engineering. - : Elsevier BV. - 2352-7102. ; 84
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Tidskriftsartikel (refereegranskat)abstract
- The oily particles produced by aerosolization of the Metalworking fluids (MWFs) pose a threat to human health. To quantify the transmission of oily particles for developing mitigation strategy, the possible particle volatilization, adhesion and coagulation during air transmission should be determined. Therefore, this study firstly by measured the particle size distributions at and away from the emission source in the laboratory. Then, to further verify the results obtained in the laboratory, the particle size distributions of oily particles in a machining workshop were measured. Meanwhile, to better understand the source characteristic of oily particles, this investigation measured the water content of the oily particles in the machining workshop because such a parameter could affect the removal performance of oily particles by filtration. The results revealed that the particle size distributions of oily particles at different locations were similar regardless of the laboratory measurement or on-site measurement. Thus, the evolution of particle size distribution of oily particles during air transmission could be ignored. Besides, the oily particles in the air had a water content of 22.6 % when the MWFs with a water content of 95 % was used during turning process. Although the oily particles in the air contained a certain amount of water, they were difficult to volatilize. The oily particles in the air might mainly consist of pure oily particles and water-in-oil particles. The results in this study could provide guidance for developing better control strategies of oily particles in machining workshops.
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| 10. |
- Liu, Junwei, et al.
(författare)
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Polymer synergy for efficient hole transport in solar cells and photodetectors
- 2023
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Ingår i: Energy & Environmental Science. - : ROYAL SOC CHEMISTRY. - 1754-5692 .- 1754-5706.
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Tidskriftsartikel (refereegranskat)abstract
- Hole transport materials (HTMs) have greatly advanced the progress of solution-based electronic devices in the past few years. Nevertheless, most devices employing dopant-free organic HTMs can only deliver inferior performance. In this work, we introduced a novel "polymer synergy" strategy to develop versatile dopant-free polymer HTMs for quantum dot/perovskite solar cells and photodetectors. With this synergy strategy, the optical, electrical and aggregation properties of polymer HTMs can be modulated, resulting in complementary absorption, high hole mobility, favorable energy landscape and moderate aggregation. Moreover, a clear orientational transition was observed for the developed HTMs with a 9-fold increase in the face-on/edge-on ratio, providing a highway-like carrier transport for electronic devices, as revealed by in situ characterization and ultrafast transient absorption. With these benefits, the photovoltaic and photodetection performance of quantum dot devices were boosted from 11.8% to 13.5% and from 2.95 x 10(12) to 3.41 x 10(13) Jones (over a 10-fold increase), respectively. Furthermore, the developed polymer HTMs can also significantly enhance the photovoltaic and photodetection performance of perovskite devices from 15.1% to 22.7% and from 2.7 x 10(12) to 2.17 x 10(13)Jones with the same device structure, indicating their great application potential in the emerging optoelectronics.
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| 11. |
- Liu, Yong, et al.
(författare)
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Deletion Of XIAP reduces the severity of acute pancreatitis via regulation of cell death and nuclear factor-kappa B activity
- 2017
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Ingår i: Cell Death and Disease. - : NATURE PUBLISHING GROUP. - 2041-4889. ; 8
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Tidskriftsartikel (refereegranskat)abstract
- Severe acute pancreatitis (SAP) still remains a clinical challenge, not only for its high mortality but the uncontrolled inflammatory progression from acute pancreatitis (AP) to SAP. Cell death, including apoptosis and necrosis are critical pathology of AP, since the severity of pancreatitis correlates directly with necrosis and inversely with apoptosis Therefore, regulation of cell death from necrosis to apoptosis may have practicably therapeutic value. X-linked inhibitor of apoptosis protein (XIAP) is the best characterized member of the inhibitor of apoptosis proteins (IAP) family, but its function in AP remains unclear. In the present study, we investigated the potential role of XIAP in regulation of cell death and inflammation during acute pancreatitis. The in vivo pancreatitis model was induced by the administration of cerulein with or without lipopolysaccharide (LPS) or by the administration of L-arginine in wild-type or XIAP-deficient mice, and ex vivo model was induced by the administration of cerulein+LPS in AR42J cell line following XIAP inhibition. The severity of acute pancreatitis was determined by serum amylase activity and histological grading. XIAP deletion on cell apoptosis, necrosis and inflammatory response were examined. Caspases activities, nuclear factor kappa B (NF-kappa B) activation and receptor-interacting protein kinase1 (RIP1) degradation were assessed by western blot. Deletion of XIAP resulted in the reduction of amylase activity, decrease of NF-kappa B activation and less release of TNF-alpha and IL-6, together with increased caspases activities and RIP1 degradation, leading to enhanced apoptosis and reduced necrosis in pancreatic acinar cells and ameliorated the severity of acute pancreatitis. Our results indicate that deletion of XIAP switches cell death away from necrosis to apoptosis and decreases the inflammatory response, effectively attenuating the severity of AP/SAP. The critical role of XIAP in cell death and inflammation suggests that inhibition of XIAP represents a potential therapeutic strategy for the treatment of acute pancreatitis.
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| 12. |
- Liu, Yong, et al.
(författare)
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Resolvin D1 protects against inflammation in experimental acute pancreatitis and associated lung injury
- 2016
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Ingår i: American Journal of Physiology - Gastrointestinal and Liver Physiology. - : AMER PHYSIOLOGICAL SOC. - 0193-1857 .- 1522-1547. ; 310:5, s. G303-G309
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Tidskriftsartikel (refereegranskat)abstract
- Acute pancreatitis is an inflammatory condition that may lead to multisystemic organ failure with considerable mortality. Recently, resolvin D1 (RvD1) as an endogenous anti-inflammatory lipid mediator has been confirmed to protect against many inflammatory diseases. This study was designed to investigate the effects of RvD1 in acute pancreatitis and associated lung injury. Acute pancreatitis varying from mild to severe was induced by cerulein or cerulein combined with LPS, respectively. Mice were pretreated with RvD1 at a dose of 300 ng/mouse 30 min before the first injection of cerulein. Severity of AP was assessed by biochemical markers and histology. Serum cytokines and myeloperoxidase (MPO) levels in pancreas and lung were determined for assessing the extent of inflammatory response. NF-kappa B activation was determined by Western blotting. The injection of cerulein or cerulein combined with LPS resulted in local injury in the pancreas and corresponding systemic inflammatory changes with pronounced severity in the cerulein and LPS group. Pretreated RvD1 significantly reduced the degree of amylase, lipase, TNF-alpha, and IL-6 serum levels; the MPO activities in the pancreas and the lungs; the pancreatic NF-kappa B activation; and the severity of pancreatic injury and associated lung injury, especially in the severe acute pancreatitis model. These results suggest that RvD1 is capable of improving injury of pancreas and lung and exerting anti-inflammatory effects through the inhibition of NF-kappa B activation in experimental acute pancreatitis, with more notable protective effect in severe acute pancreatitis. These findings indicate that RvD1 may constitute a novel therapeutic strategy in the management of severe acute pancreatitis.
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| 13. |
- Long, Fei-Xiang, 1963
(författare)
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Hydrodemetallization of Petroleum - Reaction Kinetics, Activity Decay and Long-life Catalysts
- 2003
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Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- Hydrodemetallization (HDM) is an indispensable step in industrial catalytic hydroprocessing of residual oils. To develop improved HDM catalysts and reactors, a detailed knowledge of the reaction mechanisms and kinetics, and a good understanding of the mechanisms and process of the catalyst decaying are very important. Due to the complex composition of petroleum, both model compound metalloporphyrins and real petroleum feedstock are utilized in this study. In the kinetic studies of vanadyl etioporphyrin, a new model with two reversible hydrogenation steps and an irreversible hydrogenolysis step is proposed, and fits our experimental data reasonably well using either the total sum of squares or the determinant criterion. Subsequent statistical analysis shows that the parameters in the model are also determined reasonably well, but some deficiencies do exist. Further refining the new model in Langmuir-Hinshewood kinetics is concluded to lead to the adequacy. In the investigation of the initial decay of HDM catalysts, adsorption of metalloporphyrins on alumina is quantitatively confirmed. Moreover, the metal deposition is proven to have some autocatalytic activity, which is increased with the metal accumulation on alumina to some extent. However, these metal deposits are still far inferior to commercial catalysts to remove the metals from the stream. Instead of interpreting the initially declining activity as a result of catalyst deactivation, a simultaneous adsorption and reaction mechanism is firstly proposed. The initial apparent activity is an effect of a nearly constant catalytic activity of the active phase coupled with an extra decreasing adsorption on the alumina support. Consequently, the model based on the new mechanism follows the observations of the experiments using either metalloporphyrins or real petroleum feedstock reasonably well. In the evaluation of the long-term stability of HDM catalysts, the catalyst with fibrillar alumina support is quantitatively confirmed to possess a higher intrinsic activity than a commercial HDM catalyst. Furthermore, the magnitudes of the average pore size and pore volume of the two catalysts are the same. Therefore, the catalyst with fibrillar alumina support is expected to have a lower start-of-run temperature, thereby a longer effective lifetime in the refinery.
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| 14. |
- Qian, Li-Bing, et al.
(författare)
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Transmission of electrons through the conical glass capillary with the grounded conducting outer surface
- 2017
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Ingår i: Wuli xuebao. - : Acta Physica Sinica, Chinese Physical Society and Institute of Physics, Chinese Academy of Sciences. - 1000-3290. ; 66:12
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Tidskriftsartikel (refereegranskat)abstract
- The transmission of 1.5 keV-electrons through a conical glass capillary is reported. This study aims to understand the so-called guiding effect for the negatively charged particles (e.g. electrons). The guiding mechanism is understood quite well with positively charged particles in particular highly charged ions, but not clear with electrons, i. e., even the basic scheme mediated by the existence of negative charge patches to guide the electrons is still somewhat controversial.. The study of the charging-up dynamics causing the electrons transport inside the capillary will shed light on this issue. In order to perform this, a data acquisition system has been setup to follow the time evolution of the two-dimensional angular distribution of the transmitted electrons. The electrons are detected by the multi-channel plate (MCP) detector with a phosphor screen. The image from the phosphor screen is recorded by a charge-coupled device camera. The timing signals for the detected events are extracted from the back stack of the MCP detector and recorded by the data acquisition system, synchronized with the acquired images. The electron beam has a size of 0.5 mm x 0.5 mm and a divergence of less than 0.35.. The inner diameter of the straight part of the capillary is 1.2 mm and the exit diameter is 225 mu m. A small conducting aperture of 0.3 mm in diameter is placed at the entrance of the capillary. Two-dimensional angular distribution of the transmitted electrons through conical glass capillary and its time evolution are measured. The results show that the transmission rate decreases and reaches to a constant value for the completely discharged glass capillary with time going by. The centroid of the angular distribution moves to an asymptotic value while the width remains unchanged. These transmission characteristics are different from those indicated in our previous work (2016 Acta Phys: Si n: 65 204103). The difference originates from the different manipulations of the capillary outer surface. A conducting layer is coated on the outer surface of the capillary and grounded in this work. This isolates various discharge/charge channels and forms a new stable discharge channel. The transmission rate as a function of the tilt angle shows that the allowed transmission occurs at the tilt angle limited by the geometrical factors, i. e., the geometrical opening angle given by the aspect ratio as well as the beam divergence. The transmission characteristics suggest that most likely there are formed no negative patches to facilitate the electron transmission through the glass capillary at this selected beam energy. It is different from that of highly charged ions, where the formation of the charge patches prohibits the close collisions between the following ions and guides them out of the capillary.
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| 15. |
- Shang, Yuchen, et al.
(författare)
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Enhancement of short/medium-range order and thermal conductivity in ultrahard sp3 amorphous carbon by C70 precursor
- 2023
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Ingår i: Nature Communications. - : Springer Nature. - 2041-1723. ; 14:1
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Tidskriftsartikel (refereegranskat)abstract
- As an advanced amorphous material, sp3 amorphous carbon exhibits exceptional mechanical, thermal and optical properties, but it cannot be synthesized by using traditional processes such as fast cooling liquid carbon and an efficient strategy to tune its structure and properties is thus lacking. Here we show that the structures and physical properties of sp3 amorphous carbon can be modified by changing the concentration of carbon pentagons and hexagons in the fullerene precursor from the topological transition point of view. A highly transparent, nearly pure sp3−hybridized bulk amorphous carbon, which inherits more hexagonal-diamond structural feature, was synthesized from C70 at high pressure and high temperature. This amorphous carbon shows more hexagonal-diamond-like clusters, stronger short/medium-range structural order, and significantly enhanced thermal conductivity (36.3 ± 2.2 W m−1 K−1) and higher hardness (109.8 ± 5.6 GPa) compared to that synthesized from C60. Our work thus provides a valid strategy to modify the microstructure of amorphous solids for desirable properties.
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| 16. |
- Wang, Kai, et al.
(författare)
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Calculations with spectroscopic accuracy : Energies and transition rates in the nitrogen isoelectronic sequence from Ar XII to Zn XXIV
- 2016
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Ingår i: Astrophysical Journal Supplement Series. - : American Astronomical Society. - 0067-0049 .- 1538-4365. ; 223:1
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Tidskriftsartikel (refereegranskat)abstract
- Combined relativistic configuration interaction and many-body perturbation calculations are performed for the 359 fine-structure levels of the 2s2 2p3, 2 s2p4, 2p5, 2s2 2p2 3l, 2 s2p3 3l, 2p4 3l, and 2s2 2p2 4l configurations in N-like ions from Ar XII to Zn XXIV. Complete and consistent data sets of energies, wavelengths, radiative rates, oscillator strengths, and line strengths for all possible electric dipole, magnetic dipole, electric quadrupole, and magnetic quadrupole transitions among the 359 levels are given for each ion. The present work significantly increases the amount of accurate data for ions in the nitrogen-like sequence, and the accuracy of the energy levels is high enough to enable the identification and interpretation of observed spectra involving the n=3, 4 levels, for which experimental values are largely scarce. Meanwhile, the results should be of great help for modeling and diagnosing astrophysical and fusion plasmas.
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| 17. |
- Wang, Kai, et al.
(författare)
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EXTENDED RELATIVISTIC CONFIGURATION INTERACTION AND MANY-BODY PERTURBATION CALCULATIONS OF SPECTROSCOPIC DATA FOR THE N 6 CONFIGURATIONS IN Ne-LIKE IONS BETWEEN Cr XV AND Kr XXVII
- 2016
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Ingår i: Astrophysical Journal Supplement Series. - : American Astronomical Society. - 0067-0049 .- 1538-4365. ; 226:2
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Tidskriftsartikel (refereegranskat)abstract
- Level energies, wavelengths, electric dipole, magnetic dipole, electric quadrupole, and magnetic quadrupole transition rates, oscillator strengths, and line strengths from combined relativistic con guration interaction and many-body perturbation calculations are reported for the 201 ne-structure states of the 2s22p6, 2s22p53l, 2s2p63l, 2s22p54l, 2s2p64l, 2s22p55l, and 2s22p56l con gurations in all Ne-like ions between Cr XV and Kr XXVII. Calculated level energies and transition data are compared with experiments from the National Institute of Standards and Technology (NIST) and CHIANTI databases, and other recent benchmark calculations. The mean energy difference with the NIST experiments is only 0.05%. The present calculations signi cantly increase the amount of accurate spectroscopic data for the n > 3 states in a number of Ne-like ions of astrophysical interest. A complete data set should be helpful for analyzing new observations from solar and other astrophysical sources, and is also likely to be useful for modeling and diagnosing a variety of plasmas, including astronomical and fusion plasma.
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| 18. |
- Wang, Shunfeng, 1991, et al.
(författare)
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Co-utilization of quarry tailings and fly ash for non-sintered ultra-lightweight aggregates (ULWAs) by autoclave technology
- 2022
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Ingår i: Construction and Building Materials. - : Elsevier BV. - 0950-0618. ; 346
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Tidskriftsartikel (refereegranskat)abstract
- Quarry tailings as solid waste with large output bring a heavy environmental and economic burden. The main objective of this study is to investigate the feasibility of co-utilizing quarry tailings and fly ash (FA) as the main sources in preparing the lightweight aggregates (LWAs). The expand perlite powder (characterized with low density and high surface area) and two chemical foaming agents (ammonium carbonate and Al powder) was added to reduce the density of LWAs furtherly and fabricate a type of ultra-lightweight aggregates (ULWAs) through autoclave curing. In spite of the basic properties (compressive strength, 1 h of water absorption, loose bulk density and apparent particle density), the evolution of pore structures in relation to the type of foaming agents were also determined by combining scanning electron microscope (SEM), mercury intrusion porosimetry (MIP) and Nuclear Magnetic Resonance (NMR). The results show that increasing the expand perlite content could increases the compressive strength and water absorption, decreases the loose bulk density, apparent density and the total porosity. The pores wall gradually reduces with the increase of chemical foaming agents. Isolated pores will transform into connected pores, which also increase the most probable pore diameter and total porosity. The loose bulk density of specimens with 3 wt% (NH4)2CO3 and Al powder are 873 kg/m3 and 798 kg/m3 compared to blank (1132 kg/m3). This work lays a solid foundation for the design and preparation of ULWAs from solid wastes.
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| 19. |
- Wang, Shunfeng, 1991, et al.
(författare)
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Resourceful utilization of quarry tailings in the preparation of non-sintered high-strength lightweight aggregates
- 2022
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Ingår i: Construction and Building Materials. - : Elsevier BV. - 0950-0618. ; 334
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Tidskriftsartikel (refereegranskat)abstract
- Quarry tailings are usually stockpiled due to stable crystalline structures below 100 °C and abundant sources, which lead to a serious environmental impacts and high ecological risks. This paper presents a study of transforming the fly ash and quarry tailings as the main raw materials into lightweight aggregates (LWAs) for using in civil engineering. A novel curing regime (autoclave technology) has been proposed to obtain higher compressive strength of LWAs. The effects of curing parameters (including temperature and steam pressure) on the properties (compressive strength, water absorption, loose bulk density, phase composition, pore structure and microstructure) of LWAs were systematically evaluated. On the other hand, this research also studies the effect of cement content on the basic properties of LWAs, which was decreased from 30 to 10 wt% for declining the CO2 emission. Results show that the strength sharply increases from 2.48 to 11.95 MPa and the water absorption decreases from 11.2 to 2.09% with increasing the elevated curing temperature from 25 to 190 °C. The LWA prepared with 70 wt% solid wastes (fly ash and quarry tailings) at 190 °C achieved the highest strength (11.95 MPa) and the lower loose bulk density (1160 kg/m3), which could meet the requirement of Chinese LWAs standard (GB/T 17431.1-2010). The water absorption of LWAs is below 5% except sample T25. The total porosity of LWAs decreases from 39.65% to 26.32% at 150 °C and from 42.54% to 27.24% at 190 °C while the cement content increases form 10 wt% to 30 wt%. At the same time, the percentage of pores (>50 nm) also gradually decreases. While the curing temperature, pressure and cement usage are above 150 °C, 1.00 MPa and 10 wt% respectively, will promote the formation of new phase composition (analcime). That also further increases the strength and percentage of harmless pores and few harmful pores. Therefore, this research offers a new curing method for producing LWAs from 70 to 90 wt% solid waste and is a rapid and sustainable solution for the large-scale recycling of quarry tailings.
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| 20. |
- Wang, Xiao-Cheng, et al.
(författare)
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Identification of a lncRNA prognostic signature-related to stem cell index and its significance in colorectal cancer
- 2021
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Ingår i: Future Oncology. - : FUTURE MEDICINE LTD. - 1479-6694 .- 1744-8301. ; 17:23, s. 3087-3100
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Tidskriftsartikel (refereegranskat)abstract
- Background: The relationship between long noncoding RNAs (lncRNAs) and the mRNA stemness index (mRNAsi) in colorectal cancer (CRC) is still unclear. Materials & methods: The mRNAsi, mRNAsi-related lncRNAs and their clinical significance were analyzed by bioinformatic approaches in The Cancer Genome Atlas (TCGA)-COREAD dataset. Results: mRNAsi was negatively related to pathological features but positively related to overall survival and recurrence-free survival in CRC. A five mRNAsi-related lncRNAs prognostic signature was further developed and showed independent prognostic factors related to overall survival in CRC patients, due to the five mRNAsi-related lncRNAs involved in several pathways of the cancer stem cells and malignant cancer cell phenotypes. Conclusion: The present study highlights the potential roles of mRNAsi-related lncRNAs as alternative prognostic markers. Lay abstract: Previous evidence has indicated that the mRNA stem index (mRNAsi) is representative of the stemness of cancer stem cells (CSCs), whereas long noncoding RNAs (lncRNAs) may be crucial regulators in CSC phenotype. Nevertheless, the relationship between lncRNAs and mRNAsi in CRC is still unclear. Our results show that the mRNAsi was negatively related to pathological features and positively related to prognosis in CRC. Five mRNAsi-related lncRNAs were further identified and developed as a prognostic signature that could independently predict survival in CRC patients due to the five mRNAsi-related lncRNAs being involved in several pathways of CSCs and malignant cancer cell phenotypes, indicating the potential roles of mRNAsi-related lncRNAs as alternative prognostic markers.
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| 21. |
- Yang, Yaohua, et al.
(författare)
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Genetic Data from Nearly 63,000 Women of European Descent Predicts DNA Methylation Biomarkers and Epithelial Ovarian Cancer Risk
- 2019
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Ingår i: Cancer Research. - : AMER ASSOC CANCER RESEARCH. - 0008-5472 .- 1538-7445. ; 79:3, s. 505-517
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Tidskriftsartikel (refereegranskat)abstract
- DNA methylation is instrumental for gene regulation. Global changes in the epigenetic landscape have been recognized as a hallmark of cancer. However, the role of DNA methylation in epithelial ovarian cancer (EOC) remains unclear. In this study, high-density genetic and DNA methylation data in white blood cells from the Framingham Heart Study (N = 1,595) were used to build genetic models to predict DNA methylation levels. These prediction models were then applied to the summary statistics of a genome-wide association study (GWAS) of ovarian cancer including 22,406 EOC cases and 40,941 controls to investigate genetically predicted DNA methylation levels in association with EOC risk. Among 62,938 CpG sites investigated, genetically predicted methylation levels at 89 CpG were significantly associated with EOC risk at a Bonferroni-corrected threshold of P < 7.94 x 10(-7). Of them, 87 were located at GWAS-identified EOC susceptibility regions and two resided in a genomic region not previously reported to be associated with EOC risk. Integrative analyses of genetic, methylation, and gene expression data identified consistent directions of associations across 12 CpG, five genes, and EOC risk, suggesting that methylation at these 12 CpG may influence EOC risk by regulating expression of these five genes, namely MAPT, HOXB3, ABHD8, ARHGAP27, and SKAP1. We identified novel DNA methylation markers associated with EOC risk and propose that methylation at multiple CpG may affect EOC risk via regulation of gene expression. Significance: Identification of novel DNA methylation markers associated with EOC risk suggests that methylation at multiple CpG may affect EOC risk through regulation of gene expression.
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| 22. |
- Yang, Yaohua, et al.
(författare)
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Genetically Predicted Levels of DNA Methylation Biomarkers and Breast Cancer Risk : Data From 228 951 Women of European Descent
- 2020
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Ingår i: Journal of the National Cancer Institute. - : Oxford University Press (OUP). - 1460-2105 .- 0027-8874. ; 112:3, s. 295-304
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Tidskriftsartikel (refereegranskat)abstract
- BACKGROUND: DNA methylation plays a critical role in breast cancer development. Previous studies have identified DNA methylation marks in white blood cells as promising biomarkers for breast cancer. However, these studies were limited by low statistical power and potential biases. Using a new methodology, we investigated DNA methylation marks for their associations with breast cancer risk. METHODS: Statistical models were built to predict levels of DNA methylation marks using genetic data and DNA methylation data from HumanMethylation450 BeadChip from the Framingham Heart Study (n = 1595). The prediction models were validated using data from the Women's Health Initiative (n = 883). We applied these models to genomewide association study (GWAS) data of 122 977 breast cancer patients and 105 974 controls to evaluate if the genetically predicted DNA methylation levels at CpG sites (CpGs) are associated with breast cancer risk. All statistical tests were two-sided. RESULTS: Of the 62 938 CpG sites CpGs investigated, statistically significant associations with breast cancer risk were observed for 450 CpGs at a Bonferroni-corrected threshold of P less than 7.94 × 10-7, including 45 CpGs residing in 18 genomic regions, that have not previously been associated with breast cancer risk. Of the remaining 405 CpGs located within 500 kilobase flaking regions of 70 GWAS-identified breast cancer risk variants, the associations for 11 CpGs were independent of GWAS-identified variants. Integrative analyses of genetic, DNA methylation, and gene expression data found that 38 CpGs may affect breast cancer risk through regulating expression of 21 genes. CONCLUSION: Our new methodology can identify novel DNA methylation biomarkers for breast cancer risk and can be applied to other diseases.
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| 23. |
- Yuan, G., et al.
(författare)
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Thermally reduced graphene oxide/carbon nanotube composite films for thermal packaging applications
- 2020
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Ingår i: Materials. - : MDPI AG. - 1996-1944. ; 13:2
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Tidskriftsartikel (refereegranskat)abstract
- Thermally reduced graphene oxide/carbon nanotube (rGO/CNT) composite films were successfully prepared by a high-temperature annealing process. Their microstructure, thermal conductivity and mechanical properties were systematically studied at different annealing temperatures. As the annealing temperature increased, more oxygen-containing functional groups were removed from the composite film, and the percentage of graphene continuously increased. When the annealing temperature increased from 1100 to 1400 °C, the thermal conductivity of the composite film also continuously increased from 673.9 to 1052.1 W m-1 K-1. Additionally, the Young's modulus was reduced by 63.6%, and the tensile strength was increased by 81.7%. In addition, the introduction of carbon nanotubes provided through-plane thermal conduction pathways for the composite films, which was beneficial for the improvement of their through-plane thermal conductivity. Furthermore, CNTs apparently improved the mechanical properties of rGO/CNT composite films. Compared with the rGO film, 1 wt% CNTs reduced the Young's modulus by 93.3% and increased the tensile strength of the rGO/CNT composite film by 60.3%, which could greatly improve its flexibility. Therefore, the rGO/CNT composite films show great potential for application as thermal interface materials (TIMs) due to their high in-plane thermal conductivity and good mechanical properties.
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| 24. |
- Zhang, Fei-yan, et al.
(författare)
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Single-step purification of sIgA from bovine colostrums by anion-exchange chromatography
- 2011
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Ingår i: Science and Technology of Food Industry. - 1002-0306.
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Tidskriftsartikel (refereegranskat)abstract
- A fraction containing sIgA(sIgA-rich fraction)was prepared from bovine colostrum by anion exchange chromatography using alkali resin. The effect of changing buffer properties(pH and ionic strength)on purity of sIgA was studied. The best result was sIgA purity increasing from 16.31% in bovine colostrum solution to 91.24% in the eluting fraction with a recovery of 47% at the condition of pH 7.0,0.03mol/L sodium phosphate. These results suggested that the anion exchange chromatography using alkali resin was a potential process for sIgA purification from bovine colostrum.
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| 25. |
- Zhao, Li-Juan, et al.
(författare)
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Lysine demethylase LSD1 delivered via small extracellular vesicles promotes gastric cancer cell stemness
- 2021
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Ingår i: EMBO Reports. - : EMBO. - 1469-221X .- 1469-3178. ; 22:8
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Tidskriftsartikel (refereegranskat)abstract
- Several studies have examined the functions of nucleic acids in small extracellular vesicles (sEVs). However, much less is known about the protein cargos of sEVs and their functions in recipient cells. This study demonstrates the presence of lysine-specific demethylase 1 (LSD1), which is the first identified histone demethylase, in the culture medium of gastric cancer cells. We show that sEVs derived from gastric cancer cells and the plasma of patients with gastric cancer harbor LSD1. The shuttling of LSD1-containing sEVs from donor cells to recipient gastric cancer cells promotes cancer cell stemness by positively regulating the expression of Nanog, OCT4, SOX2, and CD44. Additionally, sEV-delivered LSD1 suppresses oxaliplatin response of recipient cells in vitro and in vivo, whereas LSD1-depleted sEVs do not. Taken together, we demonstrate that LSD1-loaded sEVs can promote stemness and chemoresistance to oxaliplatin. These findings suggest that the LSD1 content of sEV could serve as a biomarker to predict oxaliplatin response in gastric cancer patients.
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