The current studies on power plant technologies suggest that Integrated Gasification Combined Cycle(IGCC)systems are an effective and economic CO_(2) capture technology pathway.In addition,the system in conventional c...The current studies on power plant technologies suggest that Integrated Gasification Combined Cycle(IGCC)systems are an effective and economic CO_(2) capture technology pathway.In addition,the system in conventional configuration has the advantage of being more“CO_(2) capture ready”than other technologies.Pulverized coal boilers(PC)have,however,proven high technical performance attributes and are economically often most practical technologies.To highlight the pros and cons of both technologies in connection with an integrated CO_(2) capture,a comparative analysis of ultrasupercritical PC and IGCC is carried out in this paper.The technical design,the mass and energy balance and the system optimizations are implemented by using the ECLIPSE chemical plant simulation software package.Built upon these technologies,the CO_(2) capture facilities are incorporated within the system.The most appropriate CO_(2) capture systems for the PC system selected for this work are the oxy-fuel system and the postcombustion scheme using Monoethanolamine solvent scrubber column(MEA).The IGCC systems are designed in two configurations:Water gas shift reactor and Selexol-based separation.Both options generate CO_(2)-rich and hydrogen rich-gas streams.Following the comparative analysis of the technical performance attributes of the above cycles,the economic assessment is carried out using the economic toolbox of ECLIPSE is seamlessly connected to the results of the mass and energy balance as well as the utility usages.The total cost assessment is implemented according to the stepcount exponential costing method using the dominant factors and/or a combination of parameters.Subsequently,based on a set of assumptions,the net present value estimation is implemented to calculate the breakeven electricity selling prices and the CO_(2) avoidance cost.展开更多
AIM: To investigate the therapeutic effect of autologous HBsAg-loaded dendritic cells (DCs) on patients with chronic hepatitis B. METHODS: Monocytes were isolated from fresh peripheral blood of 19 chronic HBV-infected...AIM: To investigate the therapeutic effect of autologous HBsAg-loaded dendritic cells (DCs) on patients with chronic hepatitis B. METHODS: Monocytes were isolated from fresh peripheral blood of 19 chronic HBV-infected patients by Ficoil-Hypaque density gradient centrifugation and cultured by plastic-adherence methods. DCs were induced and proliferated in the culture medium with recombinant human granulocyte-macrophage-colony- stimulating factor (rhGM-CSF) and human interleukin-4 (rhIL-4). DCs pulsed with HBsAg for twelve hours were injected into patients subcutaneously twice at intervals of two weeks. Two patients received 100 mg oral lamivudine daily for 12 mo at the same time. HBV-DNA and viral markers in sera of patients were tested every two months. RESULTS: By the end of 2003, 11 of 19 (57.9%) patients had a clinical response to DC-treatment. HBeAg of 10 (52.6%) patients became negative, and the copies of HBV-DNA decreased 101.77±2.39 averagely (t = 3.13, P<0.01). Two cases co-treated with DCs and lamivudine had a complete clinical response. There were no significant differences in the efficient rate between the cases with ALT level lower than 2xULN and those with ALT level higher than 2xULN before treatment (X2 = 0.0026). CONCLUSION: Autologous DC-vaccine induced in vitro can effectively suppress HBV replication, reduce the virus load in sera, eliminate HBeAg and promote HBeAg/anti-HBe transformation. Not only the patients with high serum ALT levels but also those with normal ALT levels can respond to DC vaccine treatment, and the treatment combining DCs with lamivudine can eliminate viruses more effectively.展开更多
AIM: To investigate the therapeutic effect of endoscopicsphincterotomy (EST) in the treatment of choledocholithiasis and stenosing papillitis.METHODS: A total of 1 026 patients undergoing EST during July 1983 to May 2...AIM: To investigate the therapeutic effect of endoscopicsphincterotomy (EST) in the treatment of choledocholithiasis and stenosing papillitis.METHODS: A total of 1 026 patients undergoing EST during July 1983 to May 2003 at the institute were retrospectively analyzed. Chronic pancreatitis was diagnosed in 63 (6.1%),cholecystolithiasis and choledocholithiasis in 549 (53.5%),stones in residual biliary duct in 249 (24.3%), stenosing papillitis in 228 (22.2%). In patients with simple stenosing papillitis, most incisions were within 0.5-1 cm in length. As for patients with chronic pancreatitis simultaneously, selective pancreatic sphincterotomy was performed, and incision was within 0.5-0.8 cm in length. For stones less than 1 cm, incision was from 1 to 1.5 cm, and for those larger than 1 cm, incision ranged from 1.5 to 3 cm. For stones more than 2 cm in diameter, detritus basket rather than simple incision was chosen. RESULTS: Of the 798 patients with choledocholithiasis, 764 (93.5%) had successful stone clearance, 215 (94.3%)out of 228 cases of stenosing papillitis were cured totally, while 63 had chronic pancreatitis developed from stenosing papillitis, 57 (90.1%) had sound remission of symptoms, though membranous stenosis emerged in 13 of 57 which was treated with balloon dilatation. After the operation, only 21 cases (2.1%) had complications such as severe pancreatitis and incision bleeding. None of the patients died.CONCLUSION: EST is an ideal surgical management with mini-invasion in the treatment of choledocholithiasis and stenosing papillitis.展开更多
AIM: To investigate the modification of baculovirus vector and the feasibility of delivering exogenous genes into mammalian cells with the culture supernatant of Spodoptera frugiperta (Sf9) cells infected by recombina...AIM: To investigate the modification of baculovirus vector and the feasibility of delivering exogenous genes into mammalian cells with the culture supernatant of Spodoptera frugiperta (Sf9) cells infected by recombinant baculoviruses. METHODS: Two recombinant baculoviruses (BacV-CMV-EGFPA, BacV-CMV-EGFPB) containing CMV-EGFP expression cassette were constructed. HepG2 cells were directly incubated with the culture supernatant of Sf9 cells infected by recombinant baculoviruses, and reporter gene transfer and expression efficiencies were analyzed by flow cytometry (FCM). The optimal transduction conditions were investigated by FCM assay in HepG2 cells. Gene-transfer and expression efficiencies in HepG2 or CV1 cells by baculovirus vectors were compared with lipofectAMINE, recombinant retrovirus and vaccinia virus expression systems. Twenty different mammalian cell lines were used to investigate the feasibility of delivering exogenous genes into different mammalian cells with the culture supernatant of infected Sf9 cells. RESULTS: CMV promoter could directly express reporter genes in Sf9 cells with a relatively low efficiency. Target cells incubated with the 1:1 diluted culture supernatant (moi=50) for 12 h at 37 ℃ could achieve the highest transduction and expression efficiencies with least impairment to cell viability. Under similar conditions the baculovirus vector could achieve the highest gene-transfer and expression efficiency than lipofectAMINE, recombinant retrovirus and vaccinia virus expression systems. Most mammalian cell lines could be transduced with recombinant baculovirus. In primate adherent culture cells the recombinant baculovirus could arrive the highest infection and expression efficiencies, but it was not very satisfactory in the cell lines from mice and suspended culture cells. CONCLUSION: Mammalian cells incubated with the culture supernatant of infected Sf9 cells could serve as a very convenient way for rapid and efficient expression of foreign genes in mammalian cells, but it might be more 展开更多
AIM: To improve the immunogenicity of receptor binding site of hepatitis B virus (HBV) on preS1 antigen using HBV core antigen as an immuno-carrier. METHODS: One to 6 tandem copies of HBV preS1 (21-47) fragment were i...AIM: To improve the immunogenicity of receptor binding site of hepatitis B virus (HBV) on preS1 antigen using HBV core antigen as an immuno-carrier. METHODS: One to 6 tandem copies of HBV preS1 (21-47) fragment were inserted into HBcAg at the sites of aa 78 and 82, and expressed in E.coli. ELISA, Western blot and animal immunization were used to analyze the antigenicity and immmunogenicity of purified particulate antigens. The ability to capture HBV by antibodies elicited by chimeric particles was detected with immuno-capture PCR. RESULTS: Recombinant antigens CI, CII, CIII carrying 1-3 copies of HBV preSl (21-47) individually could form virus-like particles (VLPs), similar to HBcAg in morphology. But recombinant antigens carrying 4-6 copies of HBV preSl (21-47) were poorly expressed in E.coli. Chimeric antigens were lacking of immunoreactivity with anti-HBc monoclonal antibodies (McAbs), but still reserved good immunoreactivity with anti-HBe McAbs. CI, CII, CIII could strongly react with anti-preS1 McAb, suggesting that preS1 (21-47) fragment was well exposed on the surface of chimeric VLPs. Three chimeric VLP antigens (CI, CII and CIII) could stimulate mice to produce high-level antibody responses, and their immunogenicity was stronger than non-particulate antigen 21-47*6, containing 6 copies of preS1 (21-47). Mouse antibodies to CI, CII and CIII were able to capture HBV virions in immuno-capture PCR assay in vitro. CONCLUSION: Chimeric particulate antigens of receptor binding site-core antigen of HBV can elicit strong antibody responses to preS1. They have a potential to be developed into prophylactic or therapeutic vaccines against HBV infection.展开更多
This paper presents an exact analytical subdomain model of dual-stator consequent-pole permanent-magnet(DSCPPM)machines accounting for tooth-tips,which can accurately predict the armature reaction field distribution i...This paper presents an exact analytical subdomain model of dual-stator consequent-pole permanent-magnet(DSCPPM)machines accounting for tooth-tips,which can accurately predict the armature reaction field distribution in DSCPPM machines.In the proposed subdomain model,the field domain is composed of four types of sub-regions,viz.magnets,outer/inner air gaps,slots and slot openings.The analytical expressions of vector potential in each sub-region are determined by boundary and interface conditions.In comparison to the analytically predicted results,the corresponding flux density field distributions computed by finite element(FE)method are analyzed,which confirms the excellent accuracy of the developed subdomain model.展开更多
Photocatalytic uranium extraction from radioactive nuclear wastewater and seawater is critical for promoting the sustainable advancement of nuclear industry,but the complexity of real-world environments,particularly t...Photocatalytic uranium extraction from radioactive nuclear wastewater and seawater is critical for promoting the sustainable advancement of nuclear industry,but the complexity of real-world environments,particularly the occurrence of anoxic and oxygen-enriched states,presents significant challenges to effective uranium extraction.Here,a layered hollow core–shell structure of Bi_(2)O_(3)/g-C_(3)N_(4)Z-scheme heterojunction photocatalyst has been designed and successfully applied for photocatalytic uranium extraction in both aerobic and oxygen-free conditions,and the extraction efficiency of uranium can reach 98.4%and 99.0%,respectively.Moreover,the photocatalyst still has ultra-high extraction efficiency under the influence of pH,inorganic ions,and other factors.The exceptional capability for uranium extraction is on the one hand due to the distinctive hollow core–shell architecture,which furnishes an abundant quantity of active sites.On the other hand,benefiting from the suitable band gap structure brought by the construction of Z-scheme heterojunction,Bi_(2)O_(3)/g-C_(3)N_(4)exhibits current densities(1.00μA/cm^(2))that are 5.26 and 3.85 times greater than Bi_(2)O_(3)and g-C_(3)N_(4),respectively,and the directional migration mode of Z-scheme carriers significantly prolongs the lifetime of photogenerated charges(1.53 ns),which separately surpass the pure samples by factors of 5.10 and 3.19.Furthermore,the reaction mechanism and reaction process of photocatalytic uranium extraction are investigated in the presence and absence of oxygen,respectively.展开更多
In this work,we present a reconfigurable data glove design to capture different modes of human hand-object interactions,which are critical in training embodied artificial intelligence(AI)agents for fine manipulation t...In this work,we present a reconfigurable data glove design to capture different modes of human hand-object interactions,which are critical in training embodied artificial intelligence(AI)agents for fine manipulation tasks.To achieve various downstream tasks with distinct features,our reconfigurable data glove operates in three modes sharing a unified backbone design that reconstructs hand gestures in real time.In the tactile-sensing mode,the glove system aggregates manipulation force via customized force sensors made from a soft and thin piezoresistive material;this design minimizes interference during complex hand movements.The virtual reality(VR)mode enables real-time interaction in a physically plausible fashion:A caging-based approach is devised to determine stable grasps by detecting collision events.Leveraging a state-of-the-art finite element method,the simulation mode collects data on fine-grained four-dimensionalmanipulation events comprising hand and object motions in three-dimensional space and how the object's physical properties(e.g.,stress and energy)change in accordance with manipulation over time.Notably,the glove system presented here is the first to use high-fidelity simulation to investigate the unobservable physical and causal factors behind manipulation actions.In a series of experiments,we characterize our data glove in terms of individual sensors and the overall system.More specifically,we evaluate the system's three modes by①recording hand gestures and associated forces,②improving manipulation fluency in VR,and③producing realistic simulation effects of various tool uses,respectively.Based on these three modes,our reconfigurable data glove collects and reconstructs fine-grained human grasp data in both physical and virtual environments,thereby opening up new avenues for the learning of manipulation skills for embodied AI agents.展开更多
Programmed cell death ligand-1(PD-L1)is a T cell inhibitory immune checkpoint molecule that interacts with programmed cell death-1(PD-1)to promote immune escape of tumor cells.Compared with antibody therapies,small mo...Programmed cell death ligand-1(PD-L1)is a T cell inhibitory immune checkpoint molecule that interacts with programmed cell death-1(PD-1)to promote immune escape of tumor cells.Compared with antibody therapies,small molecule drugs show better prospects due to their advantages such as higher bioavailability,better tissue penetration,and reduced risk of immunogenicity.Here,we found that the small molecule demethylzeylasteral(Dem)can significantly downregulate the expression of PD-L1 in colorectal cancer cells and enhance the killing effect of T cells on tumor cells.Mechanistically,Dem binds to the deubiquitinating enzyme USP22 and promotes its degradation,resulting in increased ubiquitination and degradation of PD-L1 through the proteasome pathway.In addition,Dem increased the activity of cytotoxic T cells and reduced the number of myeloid-derived suppressor cells(MDSCs)and regulatory T cells(Tregs)in tumor-infiltrating lymphocytes(TILs),thereby activating the tumor immune microenvironment and inhibiting the growth of subcutaneous MC38 tumors in C57BL/6 mice.Moreover,we also found that the combination of Dem and CTLA4 antibodies can further improve the efficacy of antitumor therapy.Our study reveals the mechanism by which Dem promotes PD-L1 degradation and suggests that the combination of Dem and CTLA4 antibodies may improve the efficacy of immunotherapy.展开更多
AIM: To investigate the role of SCCA2 and other SCCA1 molecules in the process of hepatitis B virus (HBV) binding to mammalian cells. METHODS: SCCA1 and SCCA2 were isolated from HepG2. Binding protein (BP) genes were ...AIM: To investigate the role of SCCA2 and other SCCA1 molecules in the process of hepatitis B virus (HBV) binding to mammalian cells. METHODS: SCCA1 and SCCA2 were isolated from HepG2. Binding protein (BP) genes were obtained through PCR. Recombinant baculoviruses expressing SCCA1, SCCA2, BP, and different mutants were constructed and utilized to infect mammalian cells to investigate the binding ability of infected cells to HBV. RESULTS: A SCCA1 gene (A1) was isolated from HepG2, but it appeared to lack the binding ability of infected cells to HBV. Two mutants, A1-BP and BP-A1, were constructed by interchanging the carboxyl terminal of A1 and BP. Cells expressing A1-BP showed an increased virus binding capacity, but not BP-A1. Comparison of A1 sequence with the sequence of BP indicated the presence of only three amino acid changes in the carboxyl terminal, two of them were found in the reactive site loop (RSL) of SCCA1. Primary structure assay revealed that the hydrophobicity of BP and AJ515706 in this domain was strong, but A1 was relatively weak. Changing the aa349 of A1 from low hydrophobic glutamic add to high hydrophobic valine enhanced HBV binding. In contrast, HBV binding was reduced by changing the aa349 of BP from valine to glutamic acid. CONCLUSION: The results suggest that the hydrophobicity of RSL of SCCA1 may play an important role in HBV binding to cells.展开更多
Curtain walls are more and more commonly used as building facades.They allow a better daylight availability and a direct connection to exterior environments.Meanwhile,due to the high specular reflections,they may also...Curtain walls are more and more commonly used as building facades.They allow a better daylight availability and a direct connection to exterior environments.Meanwhile,due to the high specular reflections,they may also introduce negative impacts,such as glare and urban heat island effects,to the surround,especially in dense and urban environments.Therefore,it is important to effectively characterize the reflected sunlight from curtain walls.This study aimed to compare how different simulation methods can be used to characterize the reflected sunlight from curtain walls.It was found that the modeling of the sun and sky,ambient calculation,and the modeling of the building facade significantly affected the simulation results.A combination of forward and backward ray-tracing is recommended,with forward ray-tracing for identifying the curtain wall areas reflecting sunlight and backward ray-tracing for calculating illuminance due to reflected sunlight.A follow-up work is planned to investigate how different parameters will affect the simulation results and which method can produce similar results as field measurements.展开更多
Electrochemical nitrogen reduction reaction(eNRR)is one of the most important chemical reactions for the production of ammonia under ambient environment.However,the lack of in-depth understanding of the structure-acti...Electrochemical nitrogen reduction reaction(eNRR)is one of the most important chemical reactions for the production of ammonia under ambient environment.However,the lack of in-depth understanding of the structure-activity relationship impedes the development of high-performance catalysts for ammonia production.Herein,the density functional theory(DFT)calculations are performed to reveal the structure–activity relationship for the single-atom catalysts(SACs)supported on g-C_(3)N_(4),which is modified by molecular groups(i.e.,H,O,and OH).The computational results demonstrate that the W-based SACs are beneficial to produce ammonia with a low limiting potential(UL).Particularly,the W-OH@g-C_(3)N_(4) catalyst exhibits an ultralow UL of−0.22 V for eNRR.And the competitive eNRR selectivity can be identified by the dominant*N2 adsorption free energy than that of*H.Our findings provide a theoretical basis for the synthesis of efficient catalysts to produce ammonia.展开更多
Consider the partly linear regression model , where y <SUB>i </SUB>’s are responses, are known and nonrandom design points, is a compact set in the real line , β = (β <SUB>1<...Consider the partly linear regression model , where y <SUB>i </SUB>’s are responses, are known and nonrandom design points, is a compact set in the real line , β = (β <SUB>1</SUB>, ··· , β <SUB>p </SUB>)' is an unknown parameter vector, g(·) is an unknown function and {ε <SUB>i </SUB>} is a linear process, i.e., , where e <SUB>j </SUB>are i.i.d. random variables with zero mean and variance . Drawing upon B-spline estimation of g(·) and least squares estimation of β, we construct estimators of the autocovariances of {ε <SUB>i </SUB>}. The uniform strong convergence rate of these estimators to their true values is then established. These results not only are a compensation for those of [23], but also have some application in modeling error structure. When the errors {ε <SUB>i </SUB>} are an ARMA process, our result can be used to develop a consistent procedure for determining the order of the ARMA process and identifying the non-zero coeffcients of the process. Moreover, our result can be used to construct the asymptotically effcient estimators for parameters in the ARMA error process.展开更多
A test for linearity in time series with β-ARCH errors is proposed in this paper. The empirical percentage points for tset statistic are also given. The simulating results under normal and non-normal error distributi...A test for linearity in time series with β-ARCH errors is proposed in this paper. The empirical percentage points for tset statistic are also given. The simulating results under normal and non-normal error distributions show that test suggested by us is very展开更多
Kirchhoff beam migration is a beam migration method, which focuses on rapid imaging of geological structures. Although this imaging method ignores the amplitude information in the calculation process, it can calculate...Kirchhoff beam migration is a beam migration method, which focuses on rapid imaging of geological structures. Although this imaging method ignores the amplitude information in the calculation process, it can calculate multi-arrival traveltime. This migration method takes into account both imaging accuracy and computational efficiency. Kirchhoff beam migration employs coarse grid techniques in several key steps such as traveltime calculation, weight function calculation, and imaging calculation. The selection of the coarse mesh size has an important influence on the computational efficiency and imaging accuracy of the migration imaging method. This paper will analyze this influence and illustrate the analysis results by the Marmousi data sets.展开更多
AIM: Irritable bowel syndrome (IBS) is characterized by abdominal pain and changes in stool habits. Visceral hypersensitivity is a key factor in the pathophysiology of IBS. The aim of this study was to examine the eff...AIM: Irritable bowel syndrome (IBS) is characterized by abdominal pain and changes in stool habits. Visceral hypersensitivity is a key factor in the pathophysiology of IBS. The aim of this study was to examine the effect of rectal balloon-distention stimulus by blood oxygenation leveldependent functional magnetic resonance imaging (BOLDfMRI) in visceral pain center and to compare the distribution,extent, and intensity of activated areas between IBS patients and normal controls.
METHODS: Twenty-six patients with IBS and eleven normal controls were tested for rectal sensation, and the subjective pain intensity at 90 ml and 120 ml rectal balloon-distention was reported by using Visual Analogue Scale. Then, BOLDfMRI was performed at 30 ml, 60 ml, 90 ml, and 120 ml rectal balloon-distention in all subjects.
RESULTS: Rectal distention stimulation increased the activity of anterior cingulate cortex (35/37), insular cortex (37/37),prefrontal cortex (37/37), and thalamus (35/37) in most cases.At 120 ml of rectal balloon-distention, the activation area and percentage change in MR signal intensity of the regions of interest (ROI) at IC, PFC, and THAL were significantly greater in patients with IBS than that in controls. Score of pain sensation at 90 ml and 120 ml rectal balloon-distention was significantly higher in patients with IBS than that in controls.
CONCLUSION: Using fMRI, some patients with IBS can be detected having visceral hypersensitivity in response to painful rectal balloon-distention. fMRI is an objective brain imaging technique to measure the change in regional cerebral activation more precisely. In this study, IC and PFC of the IBS patients were the major loci of the CNS processing of visceral perception.展开更多
AIM: To select the optimal antisense accessible sites of survivin, a highly expressed gene in tumor tissues, in order to explore a novel approach to improve biological therapy of gastric cancer. METHODS: The 20 mer ra...AIM: To select the optimal antisense accessible sites of survivin, a highly expressed gene in tumor tissues, in order to explore a novel approach to improve biological therapy of gastric cancer. METHODS: The 20 mer random oligonucleotide library was synthesized, hybridized with in vitro transcribed total survivin cRNA, then digested by RNase H. After primer extension and autoradiography, the antisense accessible sites (AAS) of survivin were selected. Then RNADraw software was used to analyze and choose the AAS with obvious stem-loop structures, according to which the complementary antisense oligonucleotides (AS-ODNs) were synthesized and transferred into survivin highly- expressing gastric cancer cell line MKN-45. Survivin expression was detected by RT-PCR and Western Blotting. Cellular growth activities were assayed by tetrazolium bromide (MTT) colorimetry. Cellular ultrastructure was observed by electronic microscopy, while apoptosis was detected by annexin V-FITC and propidium iodide staining flow cytometry. RESULTS: Thirteen AAS of survivin were selected In vitro. Four AAS with stem-loop structures were chosen, locating at 207-226 bp, 187-206 bp, 126-145 bp and 44-63 bp of survivin cDNA respectively. When compared with non-tranfection controls, their corresponding AS-ODNs (AS-ODN1, AS-ODN2, AS-ODN3 and AS-ODN4) could reduce Survivin mRNA levels in MKN-45 cells by 54.3±±1.1% (t= 6.12, P<0.01), 86.1±±1.0% (t= 5.27, P<0.01), 32.2±±1.3% (t= 7.34, P<0.01) and 56.2±±0.9% (t = 6.45, P<0.01) respectively, while survivin protein levels were decreased by 42.2±±2.5% (t = 6.26, P<0.01), 75.4±±3.1% (t= 7.11, P<0.01), 28.3±±2.0% (t= 6.04, P<0.01) and 45.8±±1.2% (t = 6.38,P<0.01) respectively. After transfection with 600 nmol/L AS-ODN1-AS-ODN4for 24 h, cell growth was inhibited by 28.12±±1.54% (t= 7.62, P<0.01), 38.42±±3.12% (t= 7.75, P<0.01), 21.46±±2.63% (t= 5.94, P<0.01) and 32.12±1.77% (t = 6.17, P<0.01) respectively. Partial cancer cells presented the characteristic morphological changes of apopt展开更多
: Electrically induced protoplast fusion was used to produce somatic hybrids between Brassica napus L. and Sinapis alba L. Seven hybrids were obtained and verified by the simple sequence repeat and cleaved amplified p...: Electrically induced protoplast fusion was used to produce somatic hybrids between Brassica napus L. and Sinapis alba L. Seven hybrids were obtained and verified by the simple sequence repeat and cleaved amplified polymorphic sequence analysis of the gene fael, indicating that the characteristic bands from S. alba were present in the hybrids. The hybridity was also confirmed by chromosome number counting because the hybrids possessed 62 chromosomes, corresponding to the sum of fusion-parent chromosomes. Chromosome pairing at meiosis was predominantly normal, which led to high pollen fertility, ranging from 66% to 77%. All hybrids were grown to full maturity and could be fertilized and set seed after self-pollination or back-crosses with B. napus. The morphology of the hybrids resembled characteristics from both parental species. An analysis of the fatty acid composition in the seeds of F1 plants was conducted and the seeds were found to contain different amounts of erucic acid, ranging from 11.0% to 52.1%.展开更多
文摘The current studies on power plant technologies suggest that Integrated Gasification Combined Cycle(IGCC)systems are an effective and economic CO_(2) capture technology pathway.In addition,the system in conventional configuration has the advantage of being more“CO_(2) capture ready”than other technologies.Pulverized coal boilers(PC)have,however,proven high technical performance attributes and are economically often most practical technologies.To highlight the pros and cons of both technologies in connection with an integrated CO_(2) capture,a comparative analysis of ultrasupercritical PC and IGCC is carried out in this paper.The technical design,the mass and energy balance and the system optimizations are implemented by using the ECLIPSE chemical plant simulation software package.Built upon these technologies,the CO_(2) capture facilities are incorporated within the system.The most appropriate CO_(2) capture systems for the PC system selected for this work are the oxy-fuel system and the postcombustion scheme using Monoethanolamine solvent scrubber column(MEA).The IGCC systems are designed in two configurations:Water gas shift reactor and Selexol-based separation.Both options generate CO_(2)-rich and hydrogen rich-gas streams.Following the comparative analysis of the technical performance attributes of the above cycles,the economic assessment is carried out using the economic toolbox of ECLIPSE is seamlessly connected to the results of the mass and energy balance as well as the utility usages.The total cost assessment is implemented according to the stepcount exponential costing method using the dominant factors and/or a combination of parameters.Subsequently,based on a set of assumptions,the net present value estimation is implemented to calculate the breakeven electricity selling prices and the CO_(2) avoidance cost.
文摘AIM: To investigate the therapeutic effect of autologous HBsAg-loaded dendritic cells (DCs) on patients with chronic hepatitis B. METHODS: Monocytes were isolated from fresh peripheral blood of 19 chronic HBV-infected patients by Ficoil-Hypaque density gradient centrifugation and cultured by plastic-adherence methods. DCs were induced and proliferated in the culture medium with recombinant human granulocyte-macrophage-colony- stimulating factor (rhGM-CSF) and human interleukin-4 (rhIL-4). DCs pulsed with HBsAg for twelve hours were injected into patients subcutaneously twice at intervals of two weeks. Two patients received 100 mg oral lamivudine daily for 12 mo at the same time. HBV-DNA and viral markers in sera of patients were tested every two months. RESULTS: By the end of 2003, 11 of 19 (57.9%) patients had a clinical response to DC-treatment. HBeAg of 10 (52.6%) patients became negative, and the copies of HBV-DNA decreased 101.77±2.39 averagely (t = 3.13, P<0.01). Two cases co-treated with DCs and lamivudine had a complete clinical response. There were no significant differences in the efficient rate between the cases with ALT level lower than 2xULN and those with ALT level higher than 2xULN before treatment (X2 = 0.0026). CONCLUSION: Autologous DC-vaccine induced in vitro can effectively suppress HBV replication, reduce the virus load in sera, eliminate HBeAg and promote HBeAg/anti-HBe transformation. Not only the patients with high serum ALT levels but also those with normal ALT levels can respond to DC vaccine treatment, and the treatment combining DCs with lamivudine can eliminate viruses more effectively.
文摘AIM: To investigate the therapeutic effect of endoscopicsphincterotomy (EST) in the treatment of choledocholithiasis and stenosing papillitis.METHODS: A total of 1 026 patients undergoing EST during July 1983 to May 2003 at the institute were retrospectively analyzed. Chronic pancreatitis was diagnosed in 63 (6.1%),cholecystolithiasis and choledocholithiasis in 549 (53.5%),stones in residual biliary duct in 249 (24.3%), stenosing papillitis in 228 (22.2%). In patients with simple stenosing papillitis, most incisions were within 0.5-1 cm in length. As for patients with chronic pancreatitis simultaneously, selective pancreatic sphincterotomy was performed, and incision was within 0.5-0.8 cm in length. For stones less than 1 cm, incision was from 1 to 1.5 cm, and for those larger than 1 cm, incision ranged from 1.5 to 3 cm. For stones more than 2 cm in diameter, detritus basket rather than simple incision was chosen. RESULTS: Of the 798 patients with choledocholithiasis, 764 (93.5%) had successful stone clearance, 215 (94.3%)out of 228 cases of stenosing papillitis were cured totally, while 63 had chronic pancreatitis developed from stenosing papillitis, 57 (90.1%) had sound remission of symptoms, though membranous stenosis emerged in 13 of 57 which was treated with balloon dilatation. After the operation, only 21 cases (2.1%) had complications such as severe pancreatitis and incision bleeding. None of the patients died.CONCLUSION: EST is an ideal surgical management with mini-invasion in the treatment of choledocholithiasis and stenosing papillitis.
基金Supported by the grant from 863 Program,No.2001AA628120
文摘AIM: To investigate the modification of baculovirus vector and the feasibility of delivering exogenous genes into mammalian cells with the culture supernatant of Spodoptera frugiperta (Sf9) cells infected by recombinant baculoviruses. METHODS: Two recombinant baculoviruses (BacV-CMV-EGFPA, BacV-CMV-EGFPB) containing CMV-EGFP expression cassette were constructed. HepG2 cells were directly incubated with the culture supernatant of Sf9 cells infected by recombinant baculoviruses, and reporter gene transfer and expression efficiencies were analyzed by flow cytometry (FCM). The optimal transduction conditions were investigated by FCM assay in HepG2 cells. Gene-transfer and expression efficiencies in HepG2 or CV1 cells by baculovirus vectors were compared with lipofectAMINE, recombinant retrovirus and vaccinia virus expression systems. Twenty different mammalian cell lines were used to investigate the feasibility of delivering exogenous genes into different mammalian cells with the culture supernatant of infected Sf9 cells. RESULTS: CMV promoter could directly express reporter genes in Sf9 cells with a relatively low efficiency. Target cells incubated with the 1:1 diluted culture supernatant (moi=50) for 12 h at 37 ℃ could achieve the highest transduction and expression efficiencies with least impairment to cell viability. Under similar conditions the baculovirus vector could achieve the highest gene-transfer and expression efficiency than lipofectAMINE, recombinant retrovirus and vaccinia virus expression systems. Most mammalian cell lines could be transduced with recombinant baculovirus. In primate adherent culture cells the recombinant baculovirus could arrive the highest infection and expression efficiencies, but it was not very satisfactory in the cell lines from mice and suspended culture cells. CONCLUSION: Mammalian cells incubated with the culture supernatant of infected Sf9 cells could serve as a very convenient way for rapid and efficient expression of foreign genes in mammalian cells, but it might be more
基金Supported by the Excellent Scholar Incubation Plan of Ministry of Education, China
文摘AIM: To improve the immunogenicity of receptor binding site of hepatitis B virus (HBV) on preS1 antigen using HBV core antigen as an immuno-carrier. METHODS: One to 6 tandem copies of HBV preS1 (21-47) fragment were inserted into HBcAg at the sites of aa 78 and 82, and expressed in E.coli. ELISA, Western blot and animal immunization were used to analyze the antigenicity and immmunogenicity of purified particulate antigens. The ability to capture HBV by antibodies elicited by chimeric particles was detected with immuno-capture PCR. RESULTS: Recombinant antigens CI, CII, CIII carrying 1-3 copies of HBV preSl (21-47) individually could form virus-like particles (VLPs), similar to HBcAg in morphology. But recombinant antigens carrying 4-6 copies of HBV preSl (21-47) were poorly expressed in E.coli. Chimeric antigens were lacking of immunoreactivity with anti-HBc monoclonal antibodies (McAbs), but still reserved good immunoreactivity with anti-HBe McAbs. CI, CII, CIII could strongly react with anti-preS1 McAb, suggesting that preS1 (21-47) fragment was well exposed on the surface of chimeric VLPs. Three chimeric VLP antigens (CI, CII and CIII) could stimulate mice to produce high-level antibody responses, and their immunogenicity was stronger than non-particulate antigen 21-47*6, containing 6 copies of preS1 (21-47). Mouse antibodies to CI, CII and CIII were able to capture HBV virions in immuno-capture PCR assay in vitro. CONCLUSION: Chimeric particulate antigens of receptor binding site-core antigen of HBV can elicit strong antibody responses to preS1. They have a potential to be developed into prophylactic or therapeutic vaccines against HBV infection.
基金This work was supported by the National Natural Science Foundation of China under Grant 51677169 and Grant 51637009 and by the Fundamental Research Funds for the Central Universities under Grant 2017QNA4016.
文摘This paper presents an exact analytical subdomain model of dual-stator consequent-pole permanent-magnet(DSCPPM)machines accounting for tooth-tips,which can accurately predict the armature reaction field distribution in DSCPPM machines.In the proposed subdomain model,the field domain is composed of four types of sub-regions,viz.magnets,outer/inner air gaps,slots and slot openings.The analytical expressions of vector potential in each sub-region are determined by boundary and interface conditions.In comparison to the analytically predicted results,the corresponding flux density field distributions computed by finite element(FE)method are analyzed,which confirms the excellent accuracy of the developed subdomain model.
基金supported by the National Natural Science Foundation of China(Nos.12075066 and 21866007)the Innovation Project of Guangxi Graduate Education(No.YCBZ2022017).
文摘Photocatalytic uranium extraction from radioactive nuclear wastewater and seawater is critical for promoting the sustainable advancement of nuclear industry,but the complexity of real-world environments,particularly the occurrence of anoxic and oxygen-enriched states,presents significant challenges to effective uranium extraction.Here,a layered hollow core–shell structure of Bi_(2)O_(3)/g-C_(3)N_(4)Z-scheme heterojunction photocatalyst has been designed and successfully applied for photocatalytic uranium extraction in both aerobic and oxygen-free conditions,and the extraction efficiency of uranium can reach 98.4%and 99.0%,respectively.Moreover,the photocatalyst still has ultra-high extraction efficiency under the influence of pH,inorganic ions,and other factors.The exceptional capability for uranium extraction is on the one hand due to the distinctive hollow core–shell architecture,which furnishes an abundant quantity of active sites.On the other hand,benefiting from the suitable band gap structure brought by the construction of Z-scheme heterojunction,Bi_(2)O_(3)/g-C_(3)N_(4)exhibits current densities(1.00μA/cm^(2))that are 5.26 and 3.85 times greater than Bi_(2)O_(3)and g-C_(3)N_(4),respectively,and the directional migration mode of Z-scheme carriers significantly prolongs the lifetime of photogenerated charges(1.53 ns),which separately surpass the pure samples by factors of 5.10 and 3.19.Furthermore,the reaction mechanism and reaction process of photocatalytic uranium extraction are investigated in the presence and absence of oxygen,respectively.
基金the National Key Research and Development Program of China(2021ZD0150200)the Beijing Nova Program.
文摘In this work,we present a reconfigurable data glove design to capture different modes of human hand-object interactions,which are critical in training embodied artificial intelligence(AI)agents for fine manipulation tasks.To achieve various downstream tasks with distinct features,our reconfigurable data glove operates in three modes sharing a unified backbone design that reconstructs hand gestures in real time.In the tactile-sensing mode,the glove system aggregates manipulation force via customized force sensors made from a soft and thin piezoresistive material;this design minimizes interference during complex hand movements.The virtual reality(VR)mode enables real-time interaction in a physically plausible fashion:A caging-based approach is devised to determine stable grasps by detecting collision events.Leveraging a state-of-the-art finite element method,the simulation mode collects data on fine-grained four-dimensionalmanipulation events comprising hand and object motions in three-dimensional space and how the object's physical properties(e.g.,stress and energy)change in accordance with manipulation over time.Notably,the glove system presented here is the first to use high-fidelity simulation to investigate the unobservable physical and causal factors behind manipulation actions.In a series of experiments,we characterize our data glove in terms of individual sensors and the overall system.More specifically,we evaluate the system's three modes by①recording hand gestures and associated forces,②improving manipulation fluency in VR,and③producing realistic simulation effects of various tool uses,respectively.Based on these three modes,our reconfigurable data glove collects and reconstructs fine-grained human grasp data in both physical and virtual environments,thereby opening up new avenues for the learning of manipulation skills for embodied AI agents.
基金funded by the National Key Research and Development Program of China(2022YFC3502000)National Natural Science Foundation of China(Nos.82141203,82374086,and 82104459)+3 种基金Shanghai Municipal Science and Technology Major Project(ZD2021CY001,China)Innovation Team and Talents Cultivation Program of National Administration of Traditional Chinese Medicine(ZYYCXTDD-202004,China)Science and Technology Commission of Shanghai Municipality(20YF1458700,China)Organizational Key Research and Development Program of Shanghai University of Traditional Chinese Medicine(2023YZZ02,China)。
文摘Programmed cell death ligand-1(PD-L1)is a T cell inhibitory immune checkpoint molecule that interacts with programmed cell death-1(PD-1)to promote immune escape of tumor cells.Compared with antibody therapies,small molecule drugs show better prospects due to their advantages such as higher bioavailability,better tissue penetration,and reduced risk of immunogenicity.Here,we found that the small molecule demethylzeylasteral(Dem)can significantly downregulate the expression of PD-L1 in colorectal cancer cells and enhance the killing effect of T cells on tumor cells.Mechanistically,Dem binds to the deubiquitinating enzyme USP22 and promotes its degradation,resulting in increased ubiquitination and degradation of PD-L1 through the proteasome pathway.In addition,Dem increased the activity of cytotoxic T cells and reduced the number of myeloid-derived suppressor cells(MDSCs)and regulatory T cells(Tregs)in tumor-infiltrating lymphocytes(TILs),thereby activating the tumor immune microenvironment and inhibiting the growth of subcutaneous MC38 tumors in C57BL/6 mice.Moreover,we also found that the combination of Dem and CTLA4 antibodies can further improve the efficacy of antitumor therapy.Our study reveals the mechanism by which Dem promotes PD-L1 degradation and suggests that the combination of Dem and CTLA4 antibodies may improve the efficacy of immunotherapy.
基金Supported by the Cross-Century Talent Training Program of Ministry of Education, China
文摘AIM: To investigate the role of SCCA2 and other SCCA1 molecules in the process of hepatitis B virus (HBV) binding to mammalian cells. METHODS: SCCA1 and SCCA2 were isolated from HepG2. Binding protein (BP) genes were obtained through PCR. Recombinant baculoviruses expressing SCCA1, SCCA2, BP, and different mutants were constructed and utilized to infect mammalian cells to investigate the binding ability of infected cells to HBV. RESULTS: A SCCA1 gene (A1) was isolated from HepG2, but it appeared to lack the binding ability of infected cells to HBV. Two mutants, A1-BP and BP-A1, were constructed by interchanging the carboxyl terminal of A1 and BP. Cells expressing A1-BP showed an increased virus binding capacity, but not BP-A1. Comparison of A1 sequence with the sequence of BP indicated the presence of only three amino acid changes in the carboxyl terminal, two of them were found in the reactive site loop (RSL) of SCCA1. Primary structure assay revealed that the hydrophobicity of BP and AJ515706 in this domain was strong, but A1 was relatively weak. Changing the aa349 of A1 from low hydrophobic glutamic add to high hydrophobic valine enhanced HBV binding. In contrast, HBV binding was reduced by changing the aa349 of BP from valine to glutamic acid. CONCLUSION: The results suggest that the hydrophobicity of RSL of SCCA1 may play an important role in HBV binding to cells.
基金supported by Research Grant Council of the Hong Kong Special Administrative Region,China(PolyU 252029/16E).
文摘Curtain walls are more and more commonly used as building facades.They allow a better daylight availability and a direct connection to exterior environments.Meanwhile,due to the high specular reflections,they may also introduce negative impacts,such as glare and urban heat island effects,to the surround,especially in dense and urban environments.Therefore,it is important to effectively characterize the reflected sunlight from curtain walls.This study aimed to compare how different simulation methods can be used to characterize the reflected sunlight from curtain walls.It was found that the modeling of the sun and sky,ambient calculation,and the modeling of the building facade significantly affected the simulation results.A combination of forward and backward ray-tracing is recommended,with forward ray-tracing for identifying the curtain wall areas reflecting sunlight and backward ray-tracing for calculating illuminance due to reflected sunlight.A follow-up work is planned to investigate how different parameters will affect the simulation results and which method can produce similar results as field measurements.
基金supported by the National Natural Science Foundation of China(Nos.91934302,51762005,and 21878078)Key Projects of Guangxi Natural Science Foundation(No.2020GXNSFDA297015)+1 种基金the China Postdoctoral Science Foundation(No.2020M683617XB)the Opening Project of Guangxi Key Laboratory of Petrochemical Resource Processing and Process Intensification Technology(No.2020K006)。
文摘Electrochemical nitrogen reduction reaction(eNRR)is one of the most important chemical reactions for the production of ammonia under ambient environment.However,the lack of in-depth understanding of the structure-activity relationship impedes the development of high-performance catalysts for ammonia production.Herein,the density functional theory(DFT)calculations are performed to reveal the structure–activity relationship for the single-atom catalysts(SACs)supported on g-C_(3)N_(4),which is modified by molecular groups(i.e.,H,O,and OH).The computational results demonstrate that the W-based SACs are beneficial to produce ammonia with a low limiting potential(UL).Particularly,the W-OH@g-C_(3)N_(4) catalyst exhibits an ultralow UL of−0.22 V for eNRR.And the competitive eNRR selectivity can be identified by the dominant*N2 adsorption free energy than that of*H.Our findings provide a theoretical basis for the synthesis of efficient catalysts to produce ammonia.
基金the Knowledge Innovation Project of Chinese Academy of Sciences (No.KZCX2-SW-118)the National Natural Science Foundation of China (No.70221001).
文摘Consider the partly linear regression model , where y <SUB>i </SUB>’s are responses, are known and nonrandom design points, is a compact set in the real line , β = (β <SUB>1</SUB>, ··· , β <SUB>p </SUB>)' is an unknown parameter vector, g(·) is an unknown function and {ε <SUB>i </SUB>} is a linear process, i.e., , where e <SUB>j </SUB>are i.i.d. random variables with zero mean and variance . Drawing upon B-spline estimation of g(·) and least squares estimation of β, we construct estimators of the autocovariances of {ε <SUB>i </SUB>}. The uniform strong convergence rate of these estimators to their true values is then established. These results not only are a compensation for those of [23], but also have some application in modeling error structure. When the errors {ε <SUB>i </SUB>} are an ARMA process, our result can be used to develop a consistent procedure for determining the order of the ARMA process and identifying the non-zero coeffcients of the process. Moreover, our result can be used to construct the asymptotically effcient estimators for parameters in the ARMA error process.
文摘A test for linearity in time series with β-ARCH errors is proposed in this paper. The empirical percentage points for tset statistic are also given. The simulating results under normal and non-normal error distributions show that test suggested by us is very
基金Supported by projects of the Natural Science Foundation of China(No.41804100)the China Postdoctoral Science Foundation(No.2018M640910)the Fundamental Research Funds for the Central Universities(No.2682018CX36)
文摘Kirchhoff beam migration is a beam migration method, which focuses on rapid imaging of geological structures. Although this imaging method ignores the amplitude information in the calculation process, it can calculate multi-arrival traveltime. This migration method takes into account both imaging accuracy and computational efficiency. Kirchhoff beam migration employs coarse grid techniques in several key steps such as traveltime calculation, weight function calculation, and imaging calculation. The selection of the coarse mesh size has an important influence on the computational efficiency and imaging accuracy of the migration imaging method. This paper will analyze this influence and illustrate the analysis results by the Marmousi data sets.
文摘AIM: Irritable bowel syndrome (IBS) is characterized by abdominal pain and changes in stool habits. Visceral hypersensitivity is a key factor in the pathophysiology of IBS. The aim of this study was to examine the effect of rectal balloon-distention stimulus by blood oxygenation leveldependent functional magnetic resonance imaging (BOLDfMRI) in visceral pain center and to compare the distribution,extent, and intensity of activated areas between IBS patients and normal controls.
METHODS: Twenty-six patients with IBS and eleven normal controls were tested for rectal sensation, and the subjective pain intensity at 90 ml and 120 ml rectal balloon-distention was reported by using Visual Analogue Scale. Then, BOLDfMRI was performed at 30 ml, 60 ml, 90 ml, and 120 ml rectal balloon-distention in all subjects.
RESULTS: Rectal distention stimulation increased the activity of anterior cingulate cortex (35/37), insular cortex (37/37),prefrontal cortex (37/37), and thalamus (35/37) in most cases.At 120 ml of rectal balloon-distention, the activation area and percentage change in MR signal intensity of the regions of interest (ROI) at IC, PFC, and THAL were significantly greater in patients with IBS than that in controls. Score of pain sensation at 90 ml and 120 ml rectal balloon-distention was significantly higher in patients with IBS than that in controls.
CONCLUSION: Using fMRI, some patients with IBS can be detected having visceral hypersensitivity in response to painful rectal balloon-distention. fMRI is an objective brain imaging technique to measure the change in regional cerebral activation more precisely. In this study, IC and PFC of the IBS patients were the major loci of the CNS processing of visceral perception.
基金Supported by National Natural Science Foundation of China, No.30200284Science Foundation of Huazhong University of Science and Technology
文摘AIM: To select the optimal antisense accessible sites of survivin, a highly expressed gene in tumor tissues, in order to explore a novel approach to improve biological therapy of gastric cancer. METHODS: The 20 mer random oligonucleotide library was synthesized, hybridized with in vitro transcribed total survivin cRNA, then digested by RNase H. After primer extension and autoradiography, the antisense accessible sites (AAS) of survivin were selected. Then RNADraw software was used to analyze and choose the AAS with obvious stem-loop structures, according to which the complementary antisense oligonucleotides (AS-ODNs) were synthesized and transferred into survivin highly- expressing gastric cancer cell line MKN-45. Survivin expression was detected by RT-PCR and Western Blotting. Cellular growth activities were assayed by tetrazolium bromide (MTT) colorimetry. Cellular ultrastructure was observed by electronic microscopy, while apoptosis was detected by annexin V-FITC and propidium iodide staining flow cytometry. RESULTS: Thirteen AAS of survivin were selected In vitro. Four AAS with stem-loop structures were chosen, locating at 207-226 bp, 187-206 bp, 126-145 bp and 44-63 bp of survivin cDNA respectively. When compared with non-tranfection controls, their corresponding AS-ODNs (AS-ODN1, AS-ODN2, AS-ODN3 and AS-ODN4) could reduce Survivin mRNA levels in MKN-45 cells by 54.3±±1.1% (t= 6.12, P<0.01), 86.1±±1.0% (t= 5.27, P<0.01), 32.2±±1.3% (t= 7.34, P<0.01) and 56.2±±0.9% (t = 6.45, P<0.01) respectively, while survivin protein levels were decreased by 42.2±±2.5% (t = 6.26, P<0.01), 75.4±±3.1% (t= 7.11, P<0.01), 28.3±±2.0% (t= 6.04, P<0.01) and 45.8±±1.2% (t = 6.38,P<0.01) respectively. After transfection with 600 nmol/L AS-ODN1-AS-ODN4for 24 h, cell growth was inhibited by 28.12±±1.54% (t= 7.62, P<0.01), 38.42±±3.12% (t= 7.75, P<0.01), 21.46±±2.63% (t= 5.94, P<0.01) and 32.12±1.77% (t = 6.17, P<0.01) respectively. Partial cancer cells presented the characteristic morphological changes of apopt
文摘: Electrically induced protoplast fusion was used to produce somatic hybrids between Brassica napus L. and Sinapis alba L. Seven hybrids were obtained and verified by the simple sequence repeat and cleaved amplified polymorphic sequence analysis of the gene fael, indicating that the characteristic bands from S. alba were present in the hybrids. The hybridity was also confirmed by chromosome number counting because the hybrids possessed 62 chromosomes, corresponding to the sum of fusion-parent chromosomes. Chromosome pairing at meiosis was predominantly normal, which led to high pollen fertility, ranging from 66% to 77%. All hybrids were grown to full maturity and could be fertilized and set seed after self-pollination or back-crosses with B. napus. The morphology of the hybrids resembled characteristics from both parental species. An analysis of the fatty acid composition in the seeds of F1 plants was conducted and the seeds were found to contain different amounts of erucic acid, ranging from 11.0% to 52.1%.
