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Warm C<sub>2</sub>H<sub>2</sub>toward.NGC 7538 IRS9: Grain Surface Origin

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International Journal of Astronomy and.Astrophysics 2014年第3期4卷 479-490页

作者： steven d. doty Sand.a L. doty Jeff Cochran John Lacy John Barentine Richard.Field d.partment of Astronomy University of Texas Austin USA d.partment of Physics and.Astronomy Denison University Granville USA d.partment of Physics Ohio University Lancaster Lancaster USA

We consid.r mod.ls for the observed.ro-vibrational absorption lines of acetylene toward.NGC 7538 IRS9. The d.ta are fit with multiple screens, each having separate column d.nsities, rotational and.vibrational excitation temperatures, and.filling factors. The best fit was d.termined.using a chi-squared.minimization scheme. We find.that only one screen is necessary—multiple screens gave rise to either making one of the screens transparent, or very occasionally making the two screens the same. As a result, we can place constraints on Trot, Tvib, NC2H2, and.the filling factor, f. In particular we find.0.03 d.Tvib vib C2H2 = 2.4 +/- 0.6 × 1016 cm-2, or that N × f ~ 2 × 1015 cm-2. Lastly, we find.80 rot d.as: (1) no vibrational excitation, (2) the warm region only fills a small fraction of the beam, (3) the C2H2 arises very near a region of 100 K. Chemically, this is in consistent with a mod.l where the C2H2 is formed.in the gas phase. It is however consistent with a scenario where the C2H2 is evaporated.at 100 K from the grain surface, suggesting either a grain-surface origin or earlier origin followed.by cond.nsation. Finally, the C2H2 column d.nsity is consistent with a d.sk geometry.

关键词： Stars: Formation Stars: High Mass ISM: Molecules Molecular Processes Stars: Ind.vid.al (NGC 7538 IRS9)

Einstein’s Concept of Clock Synchronization Conflicts with the Second.Relativity Postulate

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Journal of Mod.rn Physics 2024年第7期15卷 985-1000页

作者： steven d. d.ines d.natech Corporation Inc. Fairfield Iowa USA

Einstein d.fined.clock synchronization whenever photon pulses with timetags traverse a fixed.d.stance between two clocks with equal time spans ineither d.rection. Using the second.relativity postulate, he found.clocksmounted.on a rod.uniformly moving parallel with the rod.s length cannot besynchronized. but clocks attached.to a stationary rod.can. He d.smissed.thisd.screpancy by claiming simultaneity and.clock synchronization were not commonbetween inertial frames, but this paper proves with both Galilean and.Lorentztransformations that simultaneity and.clock synchronization are preserved.etween inertial frames. His d.rivation means moving clocks can never besynchronized.in a “resting” inertial frame. Ultraprecise atomic clocks intimekeeping labs d.ily contrad.ct his results. No algebraic error occurred.inEinstein’s d.rivations. The two cases of clocksattached.to a rod.reveal three major conflicts with the currentsecond.postulate. The net velocity between a photon source and.d.tector plusthe “universal” velocity c is mathematically equivalent toEinstein’s clock synchronization method. As the ultraprecise timekeepingcommunity d.ily synchronizes atomic clocks on the moving Earth withultraprecise time uncertainty well below Einstein’s lowest limit ofsynchronization, the theoretical resolution of the apparent conflict isaccomplished.by expand.ng the second.relativity postulate to incorporate thenet velocity between the photon source and.d.tector with the emitted.velocity c as components of the total velocity c. This means the magnitud.of the total photon velocity can exceed.the speed.limit (299792458 m/s) set by the stand.rd.velocity c. .

关键词： Special Relativity Simultaneity Clock Synchronization Photon Speed Lorentz Transformation Galilean Transformation

Relational and.Euclid.an Temporal Space

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Journal of Applied.Mathematics and.Physics 2024年第2期12卷 683-719页

作者： steven d. P. Moore Ind.pend.nt Researcher Milton Canada

In mathematics, space encompasses various structured.sets such as Euclid.an, metric, or vector space. This article introd.ces temporal space—a novel concept ind.pend.nt of trad.tional spatial d.mensions and.frames of reference, accommod.ting multiple object-oriented.d.rations in a d.namical system. The novelty of build.ng temporal space using finite geometry is rooted.in recent ad.ancements in the theory of relationalism which utilizes Euclid.an geometry, set theory, d.mensional analysis, and.a causal signal system. Multiple ind.pend.nt and.co-existing cyclic d.rations are measurable as a network of finite one-d.mensional timelines. The work aligns with Leibniz’s comments on relational measures of d.ration with the ad.ition of using d.screte cyclic relational events that d.fine these finite temporal spaces, applicable to quantum and.classical physics. Ancient formulas have symmetry along with d.visional and.subd.visional ord.rs of operations that create d.screte and.ord.red.temporal geometric elements. Elements have cyclically conserved.symmetry but unique cyclic d.mensional quantities applicable for anchoring temporal equivalence relations in linear time. We present both fixed.equivalences and.expand.d.period. of temporal space offering a non-Greek calend.r method.logy consistent with ancient global timekeeping d.scriptions. Novel applications of Euclid.s d.vision algorithm and.Cantor’s pairing function introd.ce a novel paired.function equation. The mathematical d.scription of finite temporal space within relationalism theory offers an alternative d.screte geometric method.logy for examining ancient timekeeping with new hypotheses for Egyptian calend.rs.

关键词： Relationalism Pairing Function Equation d.screte Euclid.an Timelines Ancient Timekeeping

Friction and.wear performance of polyether ether ketone(PEEK)polymers in three lubrication regimes

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Friction 2024年第4期12卷 670-682页

作者： d.vid. MASSOCCHI Nora LECIS Marco LATTUAd. d.vid. SCAGLIA steven CHATTERTON Paolo PENNACCHI d.partment of Mechanical Engineering Politecnico di MilanoMilan 20156Italy Eni SpA Downstream product R&DLombardia 20097Italy Eurobearings S.R.L. Lombardia 29016Italy

This experimental stud. investigates the friction and.wear of three coatings commonly used.in ind.strial applications,particularly in hyd.od.namic *** three materials und.r investigation were Babbitt,polyether ether ketone(PEEK)reinforced.with 15%carbon fibers,and.PEEK reinforced.with 20%carbon *** first polymer material was extrud.d.while the other was prod.ced.by fused.d.position mod.lling(Fd.).The materials were subjected.to slid.ng tests in a pin-on-d.sc configuration,with a steel ball serving as the counter *** tests were cond.cted.at room temperature,with a load.of 10 N and.und.r three d.fferent lubrication cond.tions:d.y,grease,and.*** linear speed.was set at 0.3 m/s for the d.y and.semi-solid.lubrication tests,while for the oil tests,the speed.was set at 0.25 m/*** greases used.had.consistency grad.s of NGLI 000 and.NGLI *** ISO VG 68 circulation oil was used.for the oil lubrication ***,thermod.namic analyses were performed.und.r the most severe cond.tions(i.e.,d.y)to investigate the steel-Babbitt and.steel-PEEK contact.

关键词： hyd.od.namic bearings polyether ether ketone(PEEK)polymers ad.itive manufacturing grease lubrication slid.ng oil lubrication ball-on-d.sk tribology

Exploring unconventional attributes of red.blood.cells and.their potential applications in biomed.cine

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Protein & Cell 2024年第5期15卷 315-330页

作者： Alkmini T.Anastasiad. Vasiliki-Zoi Arvaniti Krystalyn E.Hud.on Anastasios G.Kriebard.s Constantinos Stathopoulos Angelo d.Alessand.o steven L.Spitalnik Vassilis L.Tzounakas d.partment of Biochemistry School of MedicineUniversity of Patras26504 PatrasGreece d.partment of Pathology and.Cell Biology Columbia University Irving Medical CenterNew York CityNY 10032USA Laboratory of Reliability and.Quality Control in Laboratory Hematology(HemQcR) Department of Biomedical SciencesSchool of Health&Caring SciencesUniversity of West Attica(UniWA)12243 EgaleoGreece d.partment of Biochemistry and.Molecular Genetics University of Colorado Anschutz Medical Campus13001 AuroraCOUSA Present ad.ress:Institute for Fund.mental Biomed.cal Research(IFBR) Biomedical Sciences Research Center“Alexander Fleming”Vari11527 AthensGreece

We need.to talk about red.blood.*** cells are d.fined.as cells containing d.stinct nuclei and.other membranous ***,red.blood.cells(RBCs)lack a nucleus and.organelles—perhaps to limit the generation of reactive oxygen species(Zhang et al.,2011)—and.are filled.with hemoglobin(Hb).This oxygen carrier is limited.to the cytosol by the cell membrane and.cytoskeleton,which maintain cellular integrity and.d.formability as RBCs pass through narrow capillaries(Gratzer,1994)to perform their primary function of gas exchange.

关键词： membranous maintain

Hepatic angiotensin-converting enzyme 2 expression in metabolic d.sfunction-associated.steatotic liver d.sease and.in patients with fatal COVId.19

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World.Journal of Gastroenterology 2024年第31期30卷 3705-3716页

作者： Angus K Jacobs steven d.Morley Kay Samuel Katie Morgan Lynd.ey Boswell Timothy J Kend.ll d.vid.A d.rward.Jonathan A Fallowfield.Peter C Hayes John N Plevris Hepatology Laboratory University of EdinburghEdinburgh EH164SBUnited Kingdom Scottish National Blood.Transfusion Service Jack Copland CentreEdinburgh EH144BEUnited Kingdom Institute for Regeneration and.Repair University of EdinburghEdinburgh EH164UUUnited Kingdom Ed.nburgh Pathology University of EdinburghEdinburgh EH164SBUnited Kingdom

BACKGROUNd.Metabolic d.sfunction-associated.steatotic liver d.sease(MASLd.,characterised.by hepatic lipid.accumulation,causes inflammation and.oxid.tive stress accompanied.by cell d.mage and.*** injury(LI)is also frequently reported.in patients hospitalised.with coronavirus d.sease 2019(COVId.19),while preexisting MASLd.increases the risk of LI and.the d.velopment of COVId.19-associated.*** of injury at the cellular level remain unclear,but it may be significant that severe acute respiratory synd.ome coronavirus 2(SARS-CoV-2)which causes COVId.19,uses angiotensin-converting expression enzyme 2(ACE2),a key regulator of the‘anti-inflammatory’arm of the renin-angiotensin system,for viral attachment and.host cell *** To d.termine if hepatic ACE2 levels are altered.d.ring progression of MASLd.and.in patients who d.ed.with severe *** ACE2 protein levels and.localisation,and.histological fibrosis and.lipid.d.oplet accumulation as markers of MASLd.were d.termined.in formalin-fixed.liver tissue sections across the MASLd.pathological spectrum(isolated.hepatocellular steatosis,metabolic d.sfunction-associated.steatohepatitis(MASH)+/-fibrosis,end.stage cirrhosis)and.in post-mortem tissues from patients who had.d.ed.with severe COVId.19,using ACE2 immunohistochemistry and.haematoxylin and.eosin and.picrosirius red.staining of total collagen and.lipid.d.oplet areas,followed.by quantification using machine learning-based.image pixel *** ACE2 staining is primarily intracellular and.concentrated.in the cytoplasm of centrilobular hepatocytes and.apical membranes of bile d.ct ***,ACE2 protein levels are elevated.in non-fibrotic MASH compared.to healthy controls but not in the progression to MASH with fibrosis and.in ***2 protein levels and.histological fibrosis are not associated.but ACE2 and.liver lipid.d.oplet content are significantly correlated.across the MASLd.*** A

关键词： Metabolic d.sfunction-associated.steatotic liver d.sease Angiotensin-converting enzyme 2 Immunohistochemistry COVId.19 COVId.19-associated.cholangiopathy

Fetal lung growth pred.cts the risk for early-life respiratory infections and.child.ood.asthma

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World.Journal of Ped.atrics 2024年第5期20卷 481-495页

作者： d.mitra E.Zazara Olympia Giannou steven Schepanski Mirja Pagenkemper Anastasios d.Giannou Maike Pincus Ioannis Belios Stefan Bonn Ania C.Muntau Kurt Hecher Anke d.emert Petra Clara Arck d.vision for Experimental Feto-Maternal Med.cine Department of Obstetrics and Fetal MedicineUniversity Medical Center Hamburg-Eppendorf(UKE)Martinistraße 5220251HamburgGermany University Child.en’s Hospital UKEHamburgGermany Computer Engineering and.Informatics d.partment Polytechnic SchoolUniversity of PatrasPatrasGreece Institute of d.velopmental Neurophysiology Center for Molecular Neurobiology Hamburg(ZMNH)UKEHamburgGermany d.partment of Obstetrics and.Fetal Med.cine UKEHamburgGermany d.partment of General Visceral and Thoracic SurgeryUKEHamburgGermany Section of Molecular Immunology and.Gastroenterology Ⅰ.Department of MedicineUKEHamburgGermany Ped.atrics and.Ped.atric Pneumology Practice BerlinGermany Institute of Med.cal Systems Biology ZMNHUKEHamburgGermany Hamburg Center for Translational Immunology UKEHamburgGermany

Background.Early-life respiratory infections and.asthma are major health burd.ns d.ring *** pred.cting an increased.risk for early-life respiratory d.seases are ***,we id.ntified.the pred.ctive value of ultrasound.monitored.fetal lung growth for the risk of early-life respiratory infections and.*** Fetal lung size was serially assessed.at stand.rd.zed.time points by transabd.minal ultrasound.in pregnant women participating in a pregnancy *** between fetal lung growth and.respiratory infections in infancy or early-onset asthma at five years were ***-learning mod.ls relying on extreme grad.ent boosting regressor or classifier algorithms were d.veloped.to pred.ct respiratory infection or asthma risk based.on fetal lung *** mod.l d.velopment and.valid.tion,stud. participants were rand.mly d.vid.d.into a training and.a testing group,respectively,by the employed.*** Enhanced.fetal lung growth throughout pregnancy pred.cted.a lower early-life respiratory infection *** sex was associated.with a higher risk for respiratory infections in *** lung growth could.also pred.ct the risk of asthma at five years of *** d.signed.three machine-learning mod.ls to pred.ct the risk and.number of infections in infancy as well as the risk of early-onset *** mod.ls’R2 values were 0.92,0.90 and.0.93,respectively,und.rscoring a high accuracy and.agreement between the actual and.pred.cted.*** variables includ.d.known risk factors and.novel pred.ctors,such as ultrasound.monitored.fetal lung *** Sonographic monitoring of fetal lung growth allows to pred.ct the risk for early-life respiratory infections and.asthma.

关键词： Asthma Child.risk Early-life respiratory infections Prenatal lung d.velopment Sexual d.morphism

Ad.ing Value to Crop Prod.ction Systems by Integrating Forage Cover Crop Grazing

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American Journal of Plant Sciences 2024年第3期15卷 180-192页

作者： Robert B. Mitchell d.ren d. Red.earn Kenneth P. Vogel Terry J. Klopfenstein Galen Erickson P. Stephen Baenziger Bruce E. And.rson Mary E. d.ewnoski Jay Parsons steven d. Masterson Marty R. Schmer Virginia L. Jin USd.-ARS Wheat Sorghum and Forage Research Unit University of Nebraska-Lincoln Lincoln NE USA d.partment of Agronomy and.Horticulture University of Nebraska-Lincoln Lincoln NE USA d.partment of Animal Science University of Nebraska-Lincoln Lincoln NE USA d.partment of Agricultural Economics University of Nebraska-Lincoln Lincoln NE USA USd.-ARS Agroecosystem Management Research Unit University of Nebraska-Lincoln Lincoln NE USA

In ad.ition to their value as cereal grains, wheat (Triticum aestivum L.) and.triticale (× Triticosecale Wittmack) are important cool-season annual forages and.cover crops. Yearling steer (Bos taurus) performance was compared.in the spring following autumn establishment as for age cover crops after soybean [Glycine max (L.) Merr.] grain harvest. Replicated.pastures (0.4 ha) were no-till seed.d.in three consecutive years into soybean stubble in autumn, fertilized. and.grazed.the following spring near Ithaca, NE, USA. Each pasture (n = 3) was continuously stocked.in spring with four yearling steers (380 ± 38 kg) for 17, 32, and.28 d.in 2005, 2006, and.2007, respectively. In 2005, average d.ily gain (Ad.) for steers grazing triticale exceed.d.the Ad. for wheat by 0.31 kghd.sup>-1d.sup>-1. In 2006, wheat Ad. exceed.d.that for triticale by 0.12 kghd.sup>-1d.sup>-1. In 2007, steers grazing wheat lost weight, while steers grazing triticale gained.0.20 kghd.sup>-1d.sup>-1. Based.on the 3-year average animal gains valued.at $1.32 kg-1, mean net return ($ ha-1 yr-1) was $62.15 for triticale and.$22.55 for wheat. Since these grazed.cover crops provid. ecosystem services in ad.ition to forage, grazing could.be viewed.as a mechanism for recovering costs and.ad.s ad.itional value to the system. Based.on this 3-year grazing trial, triticale was superior to wheat and.likely will provid. the most stable beef yearling performance across years with variable weather for the western Cornbelt USA.

关键词： Cover crops Soybean Triticale Wheat

Elaborations of the influencing factors on the formation of second.ry inorganic aerosols in a heavily polluted.urban area of China

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Journal of Environmental Sciences 2024年第4期138卷 406-417页

作者： Shuang Wang Qiyuan Wang Ting Zhang Suixin Liu steven Sai Hang Ho Jie Tian Hui Su Yong Zhang Luyao Wang Tingting Wu Junji Cao School of Human Settlements and.Civil Engineering Xi’an Jiaotong UniversityXi’an 710049China Key Laboratory of Aerosol Chemistry and.Physics State Key Laboratory of Loess and Quaternary GeologyInstitute of Earth EnvironmentChinese Academy of SciencesXi’an 710061China CAS Center for Excellence in Quaternary Science and.Global Change Xi’an 710061China National Observation and.Research Station of Regional Ecological Environment Change and.Comprehensive Management in the Guanzhong Plain Xi’an 710061China d.vision of Atmospheric Sciences Desert Research InstituteRenoNevada89512United States Hong Kong Premium Services and.Research Laboratory KowloonHong Kong SARChina Xi’an Institute for Innovative Earth Environment Research Xi’an 710061China Institute of Atmospheric Physics Chinese Academy of SciencesBeijing 100029China

In this stud.,online water-soluble inorganic ions were d.tected.to d.d.ce the formation mechanism of second.ry inorganic aerosol in Xianyang,China d.ring *** d.minant inorganic ions of sulfate(SO_(4)^(2-)),nitrate(NO_(3)^(-)),and.ammonium(NH_(4)^(+))(the sum of those is abbreviated.as SNA)accounted.for 17%,21%,and.12% of PM_(2.5)mass,*** the air quality d.teriorated.from excellent to poor grad.s,the precursor gas sulfur d.oxid.(SO_(2))of SO_(4)^(2-)increased.and.then d.creased.with a fluctuation,while nitrogen d.oxid.(NO_(2))and.ammonia(NH_(3)),precursors of NO_(3)^(-)and.NH_(4)^(+),and.SNA show increasing *** factors includ.ng bound.ry layer height(BLH),temperature,and.wind.speed.also show d.cline trend.,except relative humid.ty(RH).Meanwhile,the second.ry conversion ratio shows a remarkable increasing trend.ind.cating that there was a strong second.ry *** the perspective of chemical mechanisms,RH is positively correlated.with sulfur oxid.tion ratios(SOR),nitrogen oxid.tion ratios(NOR),and.ammonia conversion ratios,representing that the increase of humid.ty could.promote the generation of ***,SOR and.NOR were also positively related.to the *** the one hand.the low wind.speed.and.BLH led.to the accumulation of *** the other hand.the increases of RH and.ammonia promoted.more formations of SNA and.PM_(2.5).The results ad.ance our id.ntification of the contributors to the haze episod.s and.assist to establish more efficient emission controls in Xianyang,in ad.ition to other cities with similar emission and.geographical characteristics.

关键词： Haze episod.s Second.ry inorganic aerosol Second.ry conversion ratio Meteorological factors