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Probing the Warm and Hot Absorbers along the Sightline of PG 0052+251
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作者 Zheng Zhou Junjie Mao +5 位作者 Taotao Fang Yijun Wang Jiayi Chen Fabrizio Nicastro Kaile Wang Yi Zhang 《Research in Astronomy and Astrophysics》 2025年第7期102-110,共9页
We analyze the absorption features in the public 73 ks XMM-Newton spectra of the Seyfert 1 galaxy PG 0052+251.Our analysis reveals the presence of a warm absorber(WA)intrinsic to the source and the hot circumgalactic ... We analyze the absorption features in the public 73 ks XMM-Newton spectra of the Seyfert 1 galaxy PG 0052+251.Our analysis reveals the presence of a warm absorber(WA)intrinsic to the source and the hot circumgalactic medium at zero redshift.The identified WA is inflowing toward the central black hole,with a velocity shift of■.The ionization parameter of the WA is■,showing strong O II and O III absorption lines,along with a significant absorption of the spectral continuum at?10?.The line of sight toward PG 0052+251 intersects the halo of M31 at an impact parameter of approximately 218 kpc.Several local(z~0)absorption lines,like O VII,O VIII,and Ne IX,were detected.The derived hydrogen column density of the local hot gas is 2.2–2.6σhigher than those estimated by several models of the Galactic hot halo,suggesting a likely contribution from the M31 halo.We also find two absorption features at24.305?and 21.410?,which are unlikely to be associated with the hot halos or the warm-hot intergalactic medium but imply the presence of an additional WA component with an outflow velocity of approximately-7000 km s^(-1). 展开更多
关键词 (galaxies:)quasars:individual(PG 0052+251) (galaxies:)quasars:absorption lines galaxies:halos galaxies:individual(M31) X-rays:galaxies
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Role of PRMTs in cancer: Could minor isoforms be leaving a mark? 被引量:14
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作者 R Mitchell Baldwin Alan Morettin Jocelyn C té 《World Journal of Biological Chemistry》 CAS 2014年第2期115-129,共15页
Protein arginine methyltransferases(PRMTs) catalyze the methylation of a variety of protein substrates, many of which have been linked to the development, progression and aggressiveness of different types of cancer. M... Protein arginine methyltransferases(PRMTs) catalyze the methylation of a variety of protein substrates, many of which have been linked to the development, progression and aggressiveness of different types of cancer. Moreover, aberrant expression of PRMTs has been observed in several cancer types. While the link between PRMTs and cancer is a relatively new area of interest, the functional implications documented thus far warrant further investigations into its therapeutic potential. However, the expression of these enzymes and the regulation of their activity in cancer are still significantly understudied. Currently there are nine main members of the PRMT family. Further, the existence of alternatively spliced isoforms for several of these family members provides an additional layer of complexity. Specifically, PRMT1, PRMT2, CARM1 and PRMT7 have been shown to have alternative isoforms and others may be currently unrealized. Our knowledge with respect to the relative expression and the specific functions of these isoforms is largely lacking and needs attention. Here we present a review of the current knowledge of theknown alternative PRMT isoforms and provide a rationale for how they may impact on cancer and represent potentially useful targets for the development of novel therapeutic strategies. 展开更多
关键词 Protein ARGININE METHYLTRANSFERASE ARGININE methylation Cancer Alternative SPLICING ISOFORMS
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Kitchen waste valorization through a mildtemperature pretreatment to enhance biogas production and fermentability:Kinetics study in mesophilic and thermophilic regimen 被引量:5
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作者 Agata Gallipoli Camilla MBraguglia +2 位作者 Andrea Gianico Daniele Montecchio Pamela Pagliaccia 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2020年第3期167-179,共13页
Biowaste valorization through anaerobic digestion is an attractive option to achieve both climate protection goals and renewable energy production.In this paper,a complete set of batch trials was carried out on kitche... Biowaste valorization through anaerobic digestion is an attractive option to achieve both climate protection goals and renewable energy production.In this paper,a complete set of batch trials was carried out on kitchen waste to investigate the effects of mild thermal pretreatment,temperature regimen and substrate/inoculum ratio.Thermal pretreatment was effective in the solubilisation of macromolecular fractions,particularly carbohydrates.The ability of the theoretical methodologies in estimating hydrogen and methane yields of complex substrates was evaluated by comparing the experimental results with the theoretical values.Despite the single batch configuration,a significant initial hydrogen production was observed,prior to methane yield.Main pretreatment effect was the gain in hydrogen production;the extent was highly variable according to the other parameters values.High hydrogen yields,up to 113 mL H2/g VSfed,were related to the prompt transformation of soluble sugars.Thermophilic regimen resulted,as expected,in faster digestions(up to 78 mL CH4/gVS/day) and sorted out pH inhibition.The relatively low methane yields(342-398 mL CH4/g VSfed) were the result of the consistent lignocellulosic content and low lipid content.Thermal pretreatment proved to be a promising option for the enhancement of hydrogen production in food waste dark fermentation. 展开更多
关键词 Kitchen waste Hydrogen Methane Thermal PRETREATMENT Kinetics Thermophilic REGIMEN
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Effect of a fermented milk containing Bifidobacterium lactis DN-173010 on Chinese constipated women 被引量:21
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作者 Yue-Xin Yang Mei He +4 位作者 Gang Hu Jie Wei Philippe Pages Xian-Hua Yang Sophie Bourdu-Naturel 《World Journal of Gastroenterology》 SCIE CAS CSCD 2008年第40期6237-6243,共7页
AIM: To investigate the effect of a fermented milk containing Bifidobacterium lactis DN-173010 and yogurt strains (BIO) on adult women with constipation in Beijing.METHODS: A total of 135 adult females with constipati... AIM: To investigate the effect of a fermented milk containing Bifidobacterium lactis DN-173010 and yogurt strains (BIO) on adult women with constipation in Beijing.METHODS: A total of 135 adult females with constipation were randomly allocated to consume for 2 wk either 100 g of the test fermented milk or 100 g of an acidified milk containing non-living bacteria (control).Stool frequency,defecation condition scores,stool consistency and food intake were recorded at baseline and after 1 and 2 wk in an intention-to-treat population of 126 subjects.In parallel,safety evaluation parameters were performed.RESULTS: At baseline,no differences were found between groups.Following consumption of test product,stool frequency was significantly increased after 1 wk (3.5 ± 1.5 vs 2.4 ± 0.6,P < 0.01) and 2 wk (4.1 ± 1.7 vs 2.4 ± 0.6,P < 0.01),vs baseline.Similarly,after 1 and 2 wk,of test product consumption,defecation condition (1.1 ± 0.9 vs 1.9 ± 1.2,P < 0.01 and 0.8 ± 1.0 vs 1.9 ± 1.2,P < 0.01,respectively) and stool consistency (1.0 ± 0.8 vs 1.5 ± 1.1,P < 0.01 and 0.6 ± 0.8 vs 1.5 ± 1.1,P < 0.01,respectively) were significantly improved.Compared with the control group,stool frequency was also significantly increased (3.5 ± 1.5 vs 2.5 ± 0.9,P < 0.01 and 4.1 ± 1.7 vs 2.6 ± 1.0,P < 0.01,respectively),and defecation condition (1.1 ± 0.9 vs 1.6 ± 1.1,P < 0.01 and 0.8 ± 1.0 vs 1.6 ± 1.1,P < 0.01,respectively) and stool consistency (1.0 ± 0.8 vs 1.4 ± 1.0,P < 0.05 and 0.6 ± 0.8 vs 1.3 ± 1.0,P < 0.01,respectively) significantly decreased after 1 and 2 wk of product consumption.During the same period,food intake did not change between the two groups,and safety parameters of the subjects were within normal ranges.CONCLUSION: This study suggests a beneficial effect of a fermented milk containing B.lactis DN-173010 on stool frequency,defecation condition and stool consistency in adult women with constipation constipated women after 1 and 2 wk of consumption. 展开更多
关键词 Probiotic Bifidobacterium lactis DN-173010 Fermented milk CONSTIPATION Stool frequency Stoolconsistency
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Characterization of the Xenopus homolog of animmediate early gene associated with cell activation: sequence analysis and regulation of its expression by thyroid hormone during amphibian metamorphosis
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作者 VIVIACTLIANG TIFFANYSEDGWICK 《Cell Research》 SCIE CAS CSCD 1997年第2期179-193,共15页
The complex transformation of a tadpole to a frogduring amphibian development is under the control of thyroid hormone (T3). T3 is known to regulate gene transcription through its nuclear receptors. We have previouslyi... The complex transformation of a tadpole to a frogduring amphibian development is under the control of thyroid hormone (T3). T3 is known to regulate gene transcription through its nuclear receptors. We have previouslyisolated many genes which are up-regulated by T3 in theintestine of Xenopus laevis tadpoles. We have now cloneda full- length cDNA for one such gene (IU12). Sequenceanalysis shows that the IU12 cDNA encodes a plasmamembrane protein with 12 transmembrane domains andhomologous to a mammalian gene associated with cell activation and organ development. Similarly, we have foundthat IU12 is activated during intestinal remodeling whenboth cell death and proliferation take place. Furthermore,IU12 is an early T3-response gene and its expression in theintestine during T3-induced metamorphosis mimics thatduring normal development. These results argue for a roleof IU12 in the signal transduction pathways leading to intestinal metamorphosis. 展开更多
关键词 Thyroid hormone Xenopus laevis cell proliferation ORGANOGENESIS transcription factor
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Analysis of Electrical Dipoles Interaction Forces as a Function of the Distance and of the Form of Electrical Force Law
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作者 Ioan Has Simona Miclaus Aurelian Has 《Journal of Applied Mathematics and Physics》 2018年第9期1886-1895,共10页
Here, we initially introduced and demonstrated two principles: orientation OR principle and attraction AT principle of electrical dipoles. The OR principle stipulates that any two electrical dipoles P1A, P1B, from two... Here, we initially introduced and demonstrated two principles: orientation OR principle and attraction AT principle of electrical dipoles. The OR principle stipulates that any two electrical dipoles P1A, P1B, from two bodies A and B, at any distance in the free state each, will be reciprocally oriented parallel and in the same sense if the electrical interaction forces F between them are of decreasing type with distance r. If the electrical interaction forces F are of increasing type with distance, the two dipoles will be reciprocally oriented parallel but on the opposite sense. The AT principle stipulate that any two electrical dipoles P1A, P1B, at any distance in the free state each, will present always a reciprocal force of attraction FD in both cases of orientation accordingly to OR principle in case of any type of electrical force F decreasing or increasing with distance. These findings may complete our previous work where we found that FD force, between two electrical dipoles P1A, P1B considered at atomic and nuclear level, is in fact the actual gravitation Newton force FN. The paper must be considered together with this work for more consistency. 展开更多
关键词 ELECTRICAL Forces Completed Coulomb’s LAW Electric DIPOLES Interactions Torsion Moment of Orientation ATTRACTION FORCE between Two DIPOLES Is GRAVITATION
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Unusual presentation of glomus tympanicum tumour: New bone formation in the middle ear
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作者 Gaurav Kumar Zenon Andreou +1 位作者 Jagdeep Singh Virk Anthony Owa 《World Journal of Clinical Cases》 SCIE 2014年第9期463-465,共3页
The objective of this study is to increase awareness of the rare presentation, diagnostic difficulties and management of glomus tympanicum of the middle ear. A 49 years old male, with a background of hypertension and ... The objective of this study is to increase awareness of the rare presentation, diagnostic difficulties and management of glomus tympanicum of the middle ear. A 49 years old male, with a background of hypertension and epilepsy, presented with a two month history of left sided conductive hearing loss, pulsatile tinnitus and headache. Clinically and radiologically a diagnosis of glomus tympanicum was made. Intraoperatively, extensive osteogenesis of the middle ear resulting in ossicular fixation and erosion was found. This patient required a two stage operation for full clearance of disease. A stapedectomy drill was used to drill off the bony overgrowth surrounding the ossicles resulting in improved hearing thresholds and full clearance of the disease at two year follow up. Glomus tympanicum can result in new bone formation in the middle ear with resultant ossicular fixation and conductive hearing loss. This can be effectively treated surgically with restoration of hearing. 展开更多
关键词 GLOMUS Tympanicum OSTEOGENESIS CONDUCTIVE HEARING LOSS
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Selecting SNP markers reflecting population origin for cacao(Theobroma cacao L.)germplasm identification 被引量:1
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作者 Osman A.Gutiérrez Kathleen Martinez +3 位作者 Dapeng Zhang Donald S.Livingstone Chris J.Turnbull Juan Carlos Motamayor 《Beverage Plant Research》 2021年第1期133-141,共9页
Cacao is one of the most economically important agricultural commodities in the world,providing the principal ingredient for the global chocolate industry.Accurate genotype identification is essential for effective co... Cacao is one of the most economically important agricultural commodities in the world,providing the principal ingredient for the global chocolate industry.Accurate genotype identification is essential for effective conservation and utilization of cacao germplasm.Here,we report the screening of 956 candidate SNPs,pre-selected from the 6 and 15K Theobroma cacao SNP Arrays using targeted Genotyping-by-Sequencing on 451 cacao germplasm accessions,representing ten known genetic groups from the tropical Americas.Based on call rate(No call rate<5%),Minor Allele Frequency(MAF>0.15)and Linkage Disequilibrium(LD≤0.5),a total of 219 SNPs were selected.The efficacy of these SNP markers for population classification was compared with the previous SSR-based analysis in cacao.The population assignment results of the retained 420 cacao accessions was highly comparable with the SSR study.The matrix of genetic distance between SSR and SNP markers is highly correlated(r=0.718;P<0.001).These results demonstrated the consistency in using the present SNP markers for cacao germplasm identification.This is our pilot project for the development of SNP markers reflecting population origin for cacao germplasm identification.These SNP markers and the selected reference germplasm for different populations are suitable for use in cacao germplasm management and crop improvement,including genotype identification,seed gardens and nursery accreditation,and cocoa authentication.Effort is being continued with the emphasis on selecting SNP markers for the detection of sub-population structures in the primary gene pool of T.cacao. 展开更多
关键词 GERMPLASM ORIGIN continued
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Evidence-based approach to providing informed consent for hip fracture surgery during the COVID-19 era
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作者 Rory Cuthbert David Ferguson +5 位作者 Babar Kayani Saeef Haque Aoun Ali Asif Parkar Peter Bates Krishna Vemulapalli 《World Journal of Orthopedics》 2021年第6期386-394,共9页
BACKGROUND Hip fractures are the most common reason for inpatient orthopaedic trauma admission.Urgent surgical intervention for hip fractures has remained a clinical priority throughout the coronavirus disease 2019(CO... BACKGROUND Hip fractures are the most common reason for inpatient orthopaedic trauma admission.Urgent surgical intervention for hip fractures has remained a clinical priority throughout the coronavirus disease 2019(COVID-19)pandemic.Despite this,there is a paucity of clinical guidance addressing the informed consent process for hip fracture surgery in COVID-19 positive patients.This is of paramount medicolegal importance in a high-risk patient population.AIM To quantify the additional perioperative risks for COVID-19 positive patients undergoing hip fracture surgery and provide clinicians with an evidence-based framework to establish an informed consent process.METHODS Two hundred and fifty nine consecutive patients undergoing surgical intervention for hip fractures in four hospitals in the United Kingdom were recruited.51 patients were confirmed positive for COVID-19.Predefined outcomes were analyzed over a 30-d postoperative period.COVID-19 positive and COVID-19 negative patients were compared after adjustment for confounding factors.RESULTS COVID-19 positive patients had more intensive care admissions(27%vs 5%,P<0.001),longer inpatient stays(median 23 d vs 9 d,P<0.001)and a higher 30-d mortality(29%vs 10%,P=0.001)than COVID-19 negative patients.Postoperative complications were evident in 74.5%of COVID-19 positive patients.35.3%of COVID-19 positive patients suffered postoperative lower respiratory tract infections with 13.7%developing acute respiratory distress syndrome(ARDS)and 9.8%experiencing symptomatic thromboembolic events.CONCLUSION The COVID-19 pandemic has created uncertainty in the medical community worldwide and poses unique challenges in providing informed consent for surgery.COVID-19 positive patients undergoing hip fracture surgery should be consented for the additional risk of postoperative complications(including lower respiratory tract infection,ARDS,deep vein thrombosis and pulmonary embolism),increased requirement for intensive care admission,longer inpatient stay and higher risk of mortality.Further,clinicians must be transparent about the potential for unknown risks as research into the long-term surgical outcomes of COVID-19 positive patients continues to evolve. 展开更多
关键词 COVID-19 Hip fractures MORTALITY MORBIDITY Outcome assessment Informed consent
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An Analysis of the Origin of the Interaction Force between Electric Charges, including Justification of the ln<i>r</i>Term in the Completed Coulomb’s Law, in HM16 Ether
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作者 Ioan Has Simona Miclaus Aurelian Has 《Journal of Modern Physics》 2019年第9期1090-1124,共35页
In this study, we demonstrate the correctness of our 2010 hypothesis regarding the need to complete Coulomb’s FC law with the term lnr, resulting in the completed FCC force. For this purpose, we consider the electric... In this study, we demonstrate the correctness of our 2010 hypothesis regarding the need to complete Coulomb’s FC law with the term lnr, resulting in the completed FCC force. For this purpose, we consider the electrical interactions between charged microparticles (MPs), which develop as fundamental vibrations (FVs) in ether, producing the vibrational strains &epsilon;and &gamma;and the resulting stresses &sigma;and &tau;, as percussions of ether cells (ECs) upon the MP surface. The stresses &sigma;?and?&tau;produce a resultant force FP, due to the percussions which constitute the real electric force FCC. The spatial effect of ether on FP is demonstrated by an analytical method, considering the electrical interaction between MPs through various equidistant spatial paths li of FVs, modelled on the basis of the Huygens principle for waves. For this issue, we utilized a numerical calculation, which could be generalized. But this spatial effect of the ether leads at a very slow decreasing of the FP forces ratio rF when doubling the distance l, in contrast to Coulomb’s FC forces whose ratio rF?decreases accentuate with doubling l. Accordingly, the necessity of including the term ln r in the FCC force, which is limited to 1.0 for doubling l, at long distances, was justified. 展开更多
关键词 Nature of ELECTRIC Charges Constitution of Microparticles Calculus of ELECTRIC FORCES from Percussions FORCES HM16 Model of ETHER with Fundamental Vibrations Completed Coulomb LAW JUSTIFICATION
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Does divergence from normal patterns of integration increase as chromosomal fusions increase in number?A test on a house mouse hybrid zone
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作者 Carmelo FRuciANO Paolo Colangelo +1 位作者 Riccardo Castiglia Paolo Franchini 《Current Zoology》 SCIE CAS CSCD 2020年第5期527-538,共12页
Chromosomal evolution is widely considered an important driver of speciation because it can promote the establishment of reproductive barriers.Karyotypic reorganization is also expected to affect the mea n phe no type... Chromosomal evolution is widely considered an important driver of speciation because it can promote the establishment of reproductive barriers.Karyotypic reorganization is also expected to affect the mea n phe no type,as well as its developme nt and patter ns of phenotypic in tegrati on,through processes such as variation in genetic linkage between quantitative trait loci or between regulatory regions and their targets.Here we explore the relationship between chromosomal evolution and phenotypic integration by analyzing a well-known house mouse parapatric contact zone between a highly derived Robertsonian(Rb)race(2n=22)and populations with standard karyotype(2n=40).Populations with hybrid karyotypes are scattered throughout the hybrid zone connecting the two parental races.Using mandible shape data and geometric morphometries,we test the hypothesis that patter ns of in tegration progressively diverge from the"normal"integration pattern observed in the standard race as they accumulate Rb fusions.We find that the main pattern of integration observed between the posterior and anterior part of the mandible can be largely attributed to allometry.We find no support for a gradual increase in divergence from normal patterns of integration as fusions accumulate.Surprisingly,however,we find that the derived Rb race(2n=22)has a distinct allometric trajectory compared with the standard race.Our results suggest that either individual fusions disproportionately affect patterns of integration or that there are mechanisms which"purge"extreme variants in hybrids(e.g.reduced fitness of hybrid shape). 展开更多
关键词 chromosomal races geometric morphometries hybrid zone INTEGRATION MODULARITY Robertsonian fusions
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Development of a Measurement Software for the Characterization of WORM Devices for Novel Memory Storage Applications
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作者 Mirko Congiu Miguel H. Boratto +1 位作者 Paride Pica Carlos F. O. Graeff 《Journal of Computer and Communications》 2018年第9期1-13,共13页
We hereby propose a software solution to perform high quality electrical measurements for the characterization of WORM (write-once read many), a new generation memory device which is being intensively studied for non-... We hereby propose a software solution to perform high quality electrical measurements for the characterization of WORM (write-once read many), a new generation memory device which is being intensively studied for non-volatile data storage. The as-proposed software is completely based on .NET framework and sample C# code. The paper performed a relevant measurement based on this software. Working WORM devices, based on a polymeric matrix embedded with gold and copper sulfide nanoparticles, have been used for test measurements. The aim of this paper is to show the main steps to develop a fully working measurement software without using any expensive dedicated software. 展开更多
关键词 WORM MEMRISTOR Electrical MEASUREMENTS MEMORY DEVICES
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The adenoviral E1A protein relieves gene repression by receptors in v/vo displaces corepressors and unliganded thyroid hormone
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作者 Yukiyasu Sato Andrew Ding +4 位作者 Rachel A Heimeier Ahmed F Yousef Joe S Mymryk Paul G Walfish Yun-Bo Shi 《Cell Research》 SCIE CAS CSCD 2009年第6期783-792,共10页
The human adenovirus type 5 early region 1A (E1A) is one of two oncogenes present in the adenovirus genome and functions by interfering with the activities of cellular regulatory proteins. The E1A gene is alternativ... The human adenovirus type 5 early region 1A (E1A) is one of two oncogenes present in the adenovirus genome and functions by interfering with the activities of cellular regulatory proteins. The E1A gene is alternatively spliced to yield five products. Earlier studies have revealed that E1A can regulate the function of thyroid hormone (T3) receptors (TRs). However, analysis in yeast compared with transfection studies in mammalian cell cultures yields surprisingly different effects. Here, we have examined the effect of E1A on TR function by using the frog oocyte in vivo system, where the effects of E1A can be studied in the context of chromatin. We demonstrate that different isoforms of E1A have distinct effects on TR function. The two longest forms inhibit both the repression by unliganded TR and activation by T3-bound TR. We further show that E1A binds to unliganded TR to displace the endogenous corepressor nuclear receptor corepressor, thus relieving the repression by unliganded TR. On the other hand, in the presence of T3, E1A inhibits gene activation by T3-bound TR indirectly, through a mechanism that requires its binding domain for the general coactivator p300. Taken together, our results thus indicate that E1A affects TR function through distinct mechanisms that are dependent upon the presence or absence of T3. 展开更多
关键词 adenoviral E1A thyroid hormone receptor COREPRESSOR COACTIVATOR CHROMATIN
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Determination of the Dynamic ITER Energy Confinement Time Scalings
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作者 Giorgio Sonnino Alberto Sonnino +2 位作者 Jarah Evslin Pasquale Nardone György Steinbrecher 《Journal of Modern Physics》 2016年第12期1429-1439,共11页
We derive the differential equation, which is satisfied by the ITER scalings for the dynamic energy confinement time. We show that this differential equation can also be obtained from the differential equation for the... We derive the differential equation, which is satisfied by the ITER scalings for the dynamic energy confinement time. We show that this differential equation can also be obtained from the differential equation for the energy confinement time, derived from the energy balance equation, when the plasma is near the steady state. We find that the values of the scaling parameters are linked to the second derivative of the power loss, estimated at the steady state. As an example of an application, the solution of the differential equation for the energy confinement time is compared with the profile obtained by solving numerically the balance equations (closed by a transport model) for a concrete Tokamak-plasma. 展开更多
关键词 Fusion Reactors THEORY Design and Computerized Simulation
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Thermogravimetric Analysis of Zirconia-Doped Ceria for Thermochemical Production of Solar Fuel
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作者 Friedemann Call Martin Roeb +4 位作者 Martin Schmücker Hélène Bru Daniel Curulla-Ferre Christian Sattler Robert Pitz-Paal 《American Journal of Analytical Chemistry》 2013年第10期37-45,共9页
Developing an efficient redox material is crucial for thermochemical cycles that produce solar fuels (e.g. H2 and CO), enabling a sustainable energy supply. In this study, zirconia-doped cerium oxide (Ce1-xZrxO2) was ... Developing an efficient redox material is crucial for thermochemical cycles that produce solar fuels (e.g. H2 and CO), enabling a sustainable energy supply. In this study, zirconia-doped cerium oxide (Ce1-xZrxO2) was tested in CO2-splitting cycles for the production of CO. The impact of the Zr-content on the splitting performance was investigated within the range 0 ≤ x < 0.4. The materials were synthesized via a citrate nitrate auto combustion route and subjected to thermogravimetric experiments. The results indicate that there is an optimal zirconium content, x = 0.15, improving the specific CO2-splitting performance by 50% compared to pure ceria. Significantly enhanced performance is observed for 0.15 ≤ x ≤ 0.225. Outside this range, the performance decreases to values of pure ceria. These results agree with theoretical studies attributing the improvements to lattice modification. Introducing Zr4+ into the fluorite structure of ceria compensates for the expansion of the crystal lattice caused by the reduction of Ce4+ to Ce3+. Regarding the reaction conditions, the most efficient composition Ce0.85Zr0.15O2 enhances the required conditions by a temperature of 60 K or one order of magnitude of the partial pressure of oxygen p(O2) compared to pure ceria. The optimal composition was tested in long-term experiments of one hundred cycles, which revealed declining splitting kinetics. 展开更多
关键词 Water Splitting CO_(2)Splitting Thermochemical Cycle CERIA CO Solar Fuels Hydrogen H_(2) ZIRCONIA Synthesis Gas
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氢中痕量硫化物分析方法探究 被引量:1
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作者 刘季业 张鹏辉 +4 位作者 李鹏辉 袁娇阳 余楠 蒋瑜 杨嘉伟 《化学研究与应用》 北大核心 2025年第2期310-318,共9页
通过对氢中硫化物气体标准物质与氮中硫化物标准物质的对比实验,我们验证了氢气样品中的硫化物可以使用氮气底硫化物标气进行标定,从而提高了实验过程的安全性。同时,我们确认了不同预浓缩参数对硫化物检测效果的影响,并提出了根据样品... 通过对氢中硫化物气体标准物质与氮中硫化物标准物质的对比实验,我们验证了氢气样品中的硫化物可以使用氮气底硫化物标气进行标定,从而提高了实验过程的安全性。同时,我们确认了不同预浓缩参数对硫化物检测效果的影响,并提出了根据样品中硫化物种类来调整仪器参数的建议。我们还提供了确定最优参数设置的实验方案。在氢中硫化物检测中,建立的校准曲线显示,各组分的线性关系良好,相关系数R2均在0.999以上。各组分硫化物的检出限均低于0.005 nmol/mol,单个样品的综合分析时间在30分钟以内。实验结果表明,系统的精密度和准确度均在较好的范围内(RSD<5%、SD<15%)。实际样品检测验证表明,该测量系统能够满足质子交换膜燃料电池用氢中硫化物的安全可靠检测需求。 展开更多
关键词 燃料电池 氢能 硫化物 检测
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挥发性有机物罐采样法质量控制的影响因素
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作者 余楠 袁华明 +5 位作者 樊禄 袁娇阳 张鹏辉 杨嘉伟 谭丽 陈波 《中国环境监测》 北大核心 2025年第3期164-171,共8页
介绍了罐采样-预浓缩-气相色谱/质谱法中关键设备的核查方法。选用氮中57组分气体标准物质,建立浓缩仪的进样通道吸附性、苏玛罐一致性及吸附性的核查方法,通过比对结果相对偏差,判断浓缩仪通路及苏玛罐对数据的影响;使用氮中异丁烷气... 介绍了罐采样-预浓缩-气相色谱/质谱法中关键设备的核查方法。选用氮中57组分气体标准物质,建立浓缩仪的进样通道吸附性、苏玛罐一致性及吸附性的核查方法,通过比对结果相对偏差,判断浓缩仪通路及苏玛罐对数据的影响;使用氮中异丁烷气体标准物质建立了稀释装置稀释比核查方法,通过与瓶装标气比对相对偏差,判断稀释仪的稀释倍数及混匀情况是否异常。该方法可以有效判断样品分析时,异常数据的来源,大幅提高数据的准确性,保证监测数据准确可靠。 展开更多
关键词 核查方法 预浓缩 苏玛罐 稀释装置
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提高高寒高海拔地区大型水电站施工控制网精度
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作者 黄金贤 《云南水力发电》 2025年第11期108-110,共3页
围绕高寒、高海拔地区大型水电站二等施工测量控制网从布设、建造、测量等多个方面提高测量精度,严格按照规范要求进行,经过科学、严谨的外业观测和内业计算校核,平差后控制网各项精度指标优于《水利水电工程施工测量规范》二等平面控... 围绕高寒、高海拔地区大型水电站二等施工测量控制网从布设、建造、测量等多个方面提高测量精度,严格按照规范要求进行,经过科学、严谨的外业观测和内业计算校核,平差后控制网各项精度指标优于《水利水电工程施工测量规范》二等平面控制网测量规范与业主要求。 展开更多
关键词 大型水电站 控制网 测量精度
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高寒、高海拔地区高精度大比例尺测图新方法
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作者 黄金贤 陈建安 《云南水力发电》 2025年第11期49-51,共3页
针对在高寒、高海拔地区的RM水电站两岸高精度大比例尺测图的新方法进行了论述,利用无人机测图+固定像控点解决了传统测量方式在高寒、高海拔地区高精度大比例尺测图应用中存在的问题,不仅获得了可靠的原始地形数据,还生产出了4D产品。
关键词 高寒、高海拔地区 大比例尺测图 固定像控点
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Endoscopic ultrasound-guided radiofrequency ablation of pancreatic tumors:Current status and future perspectives
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作者 Hussein H Okasha Eyad Gadour +1 位作者 Abdullah Zuhair Alyouzbaki Hossam E Shaaban 《World Journal of Methodology》 2025年第4期158-165,共8页
Pancreatic neoplasms present a significant therapeutic challenge due to their complex anatomy and poor prognosis.In recent years,endoscopic ultrasound guided radiofrequency ablation(EUS-RFA)has emerged as a promising ... Pancreatic neoplasms present a significant therapeutic challenge due to their complex anatomy and poor prognosis.In recent years,endoscopic ultrasound guided radiofrequency ablation(EUS-RFA)has emerged as a promising minimally invasive therapeutic option,aiming to provide targeted treatment with improved patients’outcomes.This review aims to shed light on current evidence about the efficacy,safety,and clinical outcomes of EUS-RFA in the management of pancreatic neoplasms.We conducted a comprehensive search of literature,reviewing studies that document the application of EUS-RFA in pancreatic masses.The key metrics for efficacy included tumor size reduction,pain relief,and overall survival,while safety outcomes focused on procedural complications and post-operative recovery.EUS-RFA has demonstrated potential in effectively managing both benign and malignant pancreatic neoplasms,with several studies reporting significant reductions in tumor size and symptomatic relief.The technique is associated with a favorable safety profile,characterized by a low incidence of major complications.EUS-RFA represents a valuable addition to the therapeutic arsenal for pancreatic neoplasms,offering a viable alternative to surgical interventions,especially in patients with contraindications for surgery.Further studies are needed to establish standardized protocols and long-term outcomes,enhancing its applicability and success in clinical practice. 展开更多
关键词 Endoscopic ultrasound Radiofrequency ablation Pancreatic tumors SAFETY EFFICACY
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