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

Journal of modern Physics 2024年第7期15卷 985-1000页

作者： steven D. Deines Donatech Corporation Inc. Fairfield Iowa USA

Einstein defined clock synchronization whenever photon pulses with timetags traverse a fixed distance between two clocks with equal time spans ineither direction. 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 dismissed thisdiscrepancy 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 preservedbetween inertial frames. His derivation means moving clocks can never besynchronized in a “resting” inertial frame. Ultraprecise atomic clocks intimekeeping labs daily contradict his results. No algebraic error occurred inEinstein’s derivations. The two cases of clocksattached to a rod reveal three major conflicts with the currentsecond postulate. The net velocity between a photon source and detector plusthe “universal” velocity c is mathematically equivalent toEinstein’s clock synchronization method. As the ultraprecise timekeepingcommunity daily synchronizes atomic clocks on the moving Earth withultraprecise time uncertainty well below Einstein’s lowest l.mit ofsynchronization, the theoretical resolution of the apparent conflict isaccomplished by expanding the second relativity postulate to incorporate thenet velocity between the photon source and detector with the emitted velocity c as components of the total velocity c. This means the magnitudeof the total photon velocity can exceed the speed l.mit (299792458 m/s) set by the standard velocity c. .

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

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Colorful facial.markings are associated with foraging rates and affiliative relationships in a wild group-living cichlid fish

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Current Zoology 2024年第1期70卷 70-78页

作者： Brett m.Culbert James B.Barnett Isaac Y.ligocki matthew G.Salena marian Y.l.Wong Ian m.Hamilton Sigal Balshine Department of Integrative Biology University of GuelphGuelphOntarioCanada Department of Psychology Neuroscience&BehaviourMcMaster UniversityHamiltonOntarioCanada Department of Evolution Ecologyand Organismal BiologyThe Ohio State UniversityColumbusOHUSA Department of Biology Millersville UniversityMillersvillePAUSA School of Earth Atmospheric and Life SciencesUniversity of WollongongWollongongNew South WalesAustralia Department of mathematics The Ohio State UniversityColumbusOHUSA

many animals use color to signal their quality and/or behavioral *** signals have been well studied in the contexts of competi-tion and mate choice;however,the role of these signals in nonsexual,affiliative relationships is not as well ***,we used wild social groups of the cichlid fish Neol.mprologus pulcher to investigate whether the size of a brightly colored facial patch was related to 1)individual quality,2)social dominance,and/or 3)affiliative *** with larger patches spent more time foraging and tended to perform more aggressive acts against conspecific territory *** did not find any evidence that the size of these yellow patches was related to social rank or body size,but dominant males tended to have larger patches than dominant ***,patch size had a rank-specific relationship with the number of affiliative interactions that individuals engaged *** males with large patches received fewer affiliative acts from their groupmates compared to dominant males with small ***,subordinates with large patches tended to receive more affiliative acts from their groupmates while performing fewer affiliative acts *** together,our results suggest that patch size reflects interindividual variation in foraging effort in this cichlid fish and offer some of the first evidence that colorful signals may shape affiliative relationships withinwildsocialgroups.

关键词： affiliation foraging lake Tanganyika Neol.mprologus pulcher visual signals

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In vivo measurement of NADH fluorescence lifetime in skeletal.muscle via -ber-coupled time-correlated single photon counting

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Journal of Innovative Optical Health Sciences 2024年第1期17卷 121-134页

作者： Kathryn m.Priest Jacob V.Schluns Nathania Nischal Colton l.Gattis Jeffrey C.Wolchok Timothy J.muldoon Department of Biomedical Engineering University of Arkansas FayettevilleARUSA

Nicotinamide adenine dinucleotide(NADH)is a cofactor that serves to shuttle electrons during metabolic processes such as glycolysis,the tricarboxylic acid cycle,and oxidative phosphorylation(OXPHOS).NADH is autofluorescent,and itsfluorescence lifetime can be used to infer metabolic dynamics in living ***-coupled time-correlated single photon counting(TCSPC)equipped with an implantable needle probe can be used to measure NADH lifetime in vivo,enabling investigation of changing metabolic demand during muscle contraction or tissue *** study illustrates a proof of concept for point-based,minimally-invasive NADHfluorescence lifetime measurement in *** muscle loss(Vml)injuries were created in the left tibialis anterior(TA)muscle of male Sprague Dawley *** lifetime measurements were collected before,during,and after a 30 s tetanic contraction in the injured and uninjured TA muscles,which was subsequently-t to a biexponential decay model to yield a metric of NADH utilization(cytoplasmic vs protein-bound NADH,the A11/A22 ratio).On average,this ratio was higher during and after contraction in uninjured muscle compared to muscle at rest,suggesting higher levels of free NADH in contracting and recovering muscle,indicating increased rates of *** injured muscle,this ratio was higher than uninjured muscle overall but decreased over time,which is consistent with current knowledge of infl.mmatory response to injury,suggesting tissue regeneration has *** data suggest that-ber-coupled TCSPC has the potential to measure changes in NADH binding in vivo in a minimally invasive manner that requires further investigation.

关键词： Glycolysis oxidative phosphorylation energy metabolism vol.metric muscle loss

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Phase composition,conductivity,and sensor properties of cerium-doped indium oxide

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Nano materials Science 2024年第2期6卷 193-200页

作者： m.I.Ikim G.N.Gerasimov V.F.Gromov O.J.Ilegbusi l.I.Trakhtenberg N.N.Semenov Federal Research Center for Chemical Physics of RAS MoscowRussia University of Central Florida OrlandoFLUSA moscow Institute of Physics and Technology(State University) DolgoprudnyMoscow RegionRussia l.monosov moscow State University MoscowRussia

The hydrothermal synthesis of In_(2)O_(3)and CeO_(2)–In_(2)O_(3)is investigated as well as the properties of sensor layers based on these *** the synthesis of In_(2)O_(3),intermediate products In(OH)_(3)and InOOH are formed,which are the precursors of stable cubic(c-In_(2)O_(3))and metastable rhombohedral(rh-In_(2)O_(3))phases,respectively.A transition from c-In_(2)O_(3)to rh-In_(2)O_(3)is observed with the addition of CeO_(2).The introduction of cerium into rh-In_(2)O_(3)results in a decrease in the sensor response to hydrogen,while it increases in composites based on c-In_(2)O_(3).The data on the sensor activity of the composites correlate with XPS results in which CeO_(2)causes a decrease in the concentrations of chemisorbed oxygen and oxygen vacancies in rh-In_(2)O_(3).The reverse situation is observed in composites based on c-In_(2)O_(3).Compared to In_(2)O_(3)and CeO_(2)–In_(2)O_(3)obtained by other methods,the synthesized composites demonstrate maximum response to H_(2)at low temperatures by 70–100℃,and have short response time(0.2–0.5 s),short recovery time(6–7 s),and long-term stability.A model is proposed for the dependence of sensitivity on the direction of electron transfer between In_(2)O_(3)and CeO_(2).

关键词： Cerium oxide Indium oxide Nanocomposite Hydrothermal.method Cubic phase Rhombohedral phase Sensor response Conductivity Hydrogen Response/recovery time

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Impact of device resistances in the performance of graphene‑based terahertz photodetectors

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Frontiers of Optoelectronics 2024年第2期17卷 87-97页

作者： O.Castelló Sofía m.lópez Baptista K.Watanabe T.Taniguchi E.Diez J.E.Velázquez-Pérez Y.m.meziani J.m.Caridad J.A.Delgado-Notario Department of Applied Physics University of Salamanca37008 SalamancaSpain Unidad de Excelencia en luz y materia Estructurada(l.mES) University of Salamanca37008 SalamancaSpain Research Center for Electronic and Optical.materials National Institute for Materials Science1-1 NamikiTsukuba 305-0044Japan Research Center for materials Nanoarchitectonics National Institute for Materials Science1-1 NamikiTsukuba 305-0044Japan Nanotechnology Group USAL-NanolabUniversity of Salamanca37008 SalamancaSpain

In recent years,graphene field-effect-transistors(GFETs)have demonstrated an outstanding potential for terahertz(THz)photodetection due to their fast response and *** features are essential to enable emerging THz applications,including 6G wireless communications,quantum information,bioimaging and ***,the overall performance of these photodetectors may be utterly compromised by the impact of internal resistances presented in the device,so-called access or parasitic *** this work,we provide a detailed study of the influence of internal device resistances in the photoresponse of high-mobility dual-gate GFET *** dual-gate architectures allow us to fine tune(decrease)the internal resistance of the device by an order of magnitude and consequently demonstrate an improved responsivity and noise-equivalent-power values of the photodetector,*** results can be well understood by a series resistance model,as shown by the excellent agreement found between the experimental data and theoretical *** findings are therefore relevant to understand and improve the overall performance of existing high-mobility graphene photodetectors.

关键词： Graphene THz Photodetector Field-effect transistor Plasmonic

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liquid crystal immunosensors for the selective detection of Escherichia coli with a fast analysis tool

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Photonics Research 2024年第7期12卷 1564-1573页

作者： SANDRO C.OlIVEIRA mARIA S.SOARES BÁRBARA V.GONÇAlVES ANDREIA C.m.RODRIGUES AmADEU m.V.m.SOARES RITA G.SOBRAl NUNO F.SANTOS JAN NEDOmA PEDRO l.AlmEIDA CARlOS mARQUES CICECO-Aveiro Institute of materials Physics DepartmentUniversity of Aveiro3810-193 AveiroPortugal i3N Physics DepartmentUniversity of Aveiro3810-193 AveiroPortugal Associate laboratory i4HB-Institute for Health and Bioeconomy School of Sciences and TechnologyNOVA University of Lisbon1099-085 LisbonPortugal CESAm-Centre for Environmental and marine Studies and Department of Biology University of Aveiro3810-193 AveiroPortugal Department of Telecommunications VSB-Technical University of OstravaOstrava 70800Czech Republic i3N-CENImAT School of Sciences and TechnologyNOVA University of Lisbon1099-085 LisbonPortugal UnIRE ISELPolytechnic Institute of Lisbon1549-020 LisbonPortugal Department of Physics VSB-Technical University of OstravaOstrava 70800Czech Republic

The consumption of contaminated food may cause serious illnesses,and traditional.methods to detect Escherichia coli are still associated with long waiting times and high costs given the necessity to transport samples to specialized *** is a need to develop new technologies that allow cheap,fast,and direct monitoring at the site of ***,in this work,we developed optical immunosensors for the selective detection of ***,based on liquid crystal technology,whose molecules can align in different manners depending on the boundary conditions (such as substrates) as well as the environment that they *** glass substrate was functionalized with *** antibody using cysteamine as an intermediate,and a vertical alignment was imposed on the liquid crystal.molecules by using DmOAP during *** presence of bacteria disrupts the alignment of the liquid crystal.molecules,changing the intensity of light emerging between cross polarizers,measured using a polarized optical.microscope and a *** was possible to detect *** in suspensions in the concentration range from 2.8 cells/ml to 2.8×10^(9) cells∕*** was also evaluated,and the sensors were used to analyze contaminated water samples.A prototype was developed to allow faster,in-situ,and easier analysis avoiding bulky instruments.

关键词： crystal alignment analysis

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Feeding behavior and hormoligosis associated with imidacloprid resistance in Asian citrus psyllid,Diaphorina citri

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Insect Science 2024年第4期31卷 1211-1221页

作者： Xue Dong Chen Justin George lauren m.Diepenbrock Hunter Gossett Guoping liu Jawwad A.Qureshi lukasz l.Stelinski Entomology and Nematology Department University of FloridaCitrus Research and Education CenterLake AlfredFloridaUSA Southern Insect management Research Unit USDA-ARSStonevilleMississippiUSA Entomology and Nematology Department University of FloridaSouthwest Florida Research and Education CenterImmokaleeFloridaUSA

Imidacloprid is a neonicotinoid insecticide used for managing the Asian citrus psyllid,Diaphorina citri Kuwayama,which serves as vector of phytopathogens causing citrus ***,development of resistance to neonicotinoids among populations of *** has coincided with occasional control failures in the *** objectives of this research were to(1)survey current levels of imidacloprid resistance in Florida citrus;(2)compare feeding behavior between imidacloprid-resistant and susceptible *** using electrical penetration graph recordings,and(3)investigate the possible amplification of insecticide hormoligosis associated with *** surveys confirmed that the susceptibility of *** populations to imidacloprid has decreased in commercial Florida citrus groves compared with a laboratory-susceptible *** 12 generations of selection,resistance to imidacloprid increased by 438 fold compared with the susceptible ***-susceptible *** feeding on citrus exhibited significantly more bouts associated with intercellular pathway(C),phloem penetration(D),phloem salivation(E1),and nonprobing(Np)activities than imidacloprid-resistant ***,there were no differences observed in the frequency or duration of phloem ingestion or xyl.m feeding between susceptible and resistant *** was no statistical difference in fecundity between resistant and susceptible ***,the fecundity of imidacloprid-susceptible female *** treated with a sublethal concentration of imidacloprid(lC_(25))increased significantly compared with controls,while such hormoligosis was less pronounced among imidacloprid-resistant *** results suggest that imidacloprid-resistant psyllids may cease feeding sooner than susceptible counterparts following sublethal exposure to this insecticide,indicative of a behavioral resistance mechanism.

关键词： artificial selection electrical penetration graph feeding behavior hormoligosis insecticide resistance sublethal exposure

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Corrosion Investigation by Scanning Electrochemical.microscopy of AISI 446 and Ti-Coated AISI 446 Ferritic Stainless Steel as Potential.material for Bipolar Plate in PEmWE

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Acta metallurgica Sinica(English letters) 2024年第4期37卷 607-619页

作者： Andrea Kellenberger Nicolae Vaszilcsin mircea laurentiu Dan Ion mitelea Alexandru Adrian Geana Sigrid lædre Corneliu m.Craciunescu Faculty of Industrial Chemistry and Environmental Engineering Politehnica University TimisoaraPiata Victoriei 2300006TimisoaraRomania Faculty of mechanical Engineering Politehnica University TimisoaraPiata Victoriei 2300006TimisoaraRomania SINTEF Industry 7465TrondheimNorway

The components of proton exchange membrane water electrolysers frequently experience corrosion issues, especially at high anodic polarization, that restrict the use of more affordable alternatives to titanium. Here, we investigate localized corrosion processes of bare and Ti-coated AISI 446 ferritic stainless steel under anodic polarization by scanning electrochemical.microscopy (SECm) in sodium sulphate and potassium chloride solutions. SECm approach curves and area scans measured at open-circuit potential (OCP) of the samples in the feedback mode using a redox mediator evidence a negative feedback effect caused by the surface passive film. For the anodic polarization of the sample, the substrate generation-tip collection mode enables to observe local generation of iron (II) ions, as well as formation of molecular oxygen. For the uncoated AISI 446 sample, localized corrosion is detected in sodium sulphate solution simultaneously with oxygen formation at anodic potentials of 1.0 V vs. Ag/AgCl, whereas significant pitting corrosion is observed even at 0.2 V vs. Ag/AgCl in potassium chloride solution. The Ti-coated AISI 446 sample reveals enhanced corrosion resistance in both test solutions, without any evidence of iron (II) ions generation at anodic potentials of 1.2 V vs. Ag/AgCl, where only oxygen formation is observed.

关键词： Ferritic stainless steel Corrosion Ti coating Scanning electrochemical.microscopy(SECm) magnetron sputtering Proton exchange membrane water electrolysis(PEmWE)

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Impact of COVID-19-related lifestyle changes on diabetic macular edema

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International Journal of Ophthalmology(English edition) 2024年第1期17卷 97-106页

作者： Bryce P.Johnson Yu-Guang He Zachary m.Robertson Angeline Wang Rafael l.Ufret-Vincenty Department of Ophthalmology UT Southwestern Medical CenterDallasTexas 75390-9057USA

AIm:To assess diabetic macular edema(DmE)progression during the early phases of the COVID-19 pandemic,when severe societal restrictions raised the concern of possible deterioration of health in patients with systemic conditions,particularly those requiring frequent office ***:This is a multicenter retrospective chart review of 370 patients(724 eyes)with an established diagnosis of DmE seen on 3 separate visits between January 2019 and July *** 1 was January 2019 to February 2020(considered pre-COVID-19),period 2 was march 2020 to December 2020(considered the height of the pandemic;highest level of pandemic-related clinical and societal regulations)and period 3 was January 2021 to July 2021(re-adjustment to the new“pandemic norms”).main outcome measures included visual acuity,body mass index(BmI),blood pressure(BP),hemoglobin A1c(HbA1c),macular thickness,patient adherence to scheduled ophthalmology visits,and DmE treatment(s)received at each *** facilitate measurement of macular thickness,each macula was divided into 9 Early Treatment Diabetic Retinopathy Study(ETDRS)-defined macular sectors as measured by OCT ***:There was no change of BmI,systolic BP,and diastolic BP between any of the time ***1c showed a very small increase from period 1(7.6%)to period 2(7.8%,P=0.015)and decreased back to 7.6%at period 3(P=0.12).macular thickness decreased for 100%of macular *** central.macular thickness decreased across all 3 periods from 329.5 to 316.6μm(P=0.0045).After analysis of multiple variables including HbA1c,BmI,adherence to scheduled appointments,different clinic centers,and treatment interventions,there was no easily identifiable subgroup of patients that experienced the increase in ***:DmE doesn’t worsen during the COVID-19 pandemic,instead sustaining a very small but statistically significant *** identifying a mechanism behind our findings is beyond the scope of this study,potential explanat

关键词： COVID-19 diabetic macular edema diabetic retinopathy optical coherence tomography

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In vivo and in vitro study of resorbable magnesium wires for medical implants:mg purity,surface quality,Zn alloying and pol.mer coating

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Journal of magnesium and Alloys 2024年第6期12卷 2472-2488页

作者： K.Tesar J.luňácková m.Jex m.Žaloudková R.Vrbová m.Bartoš P.Klein l.Vištejnová J.Dušková E.Filová Z.Sucharda m.Steinerová S.Habr K.Balík A.Singh Department of materials Faculty of Nuclear Sciences and Physical EngineeringCzech Technical University in PragueTrojanova 13Prague 12000Czech Republic Institute of Physics Czech Academy of SciencesNa Slovance 2Prague 18221Czech Republic Institute of Dental.medicine First Faculty of MedicineCharles University and General University Hospital in PragueKaterinská32Prague 12801Czech Republic Department of Physics Faculty of Nuclear Sciences and Physical EngineeringCzech Technical University in PragueBrehová7Prague 11519Czech Republic Department of Composites and Carbon materials Institute of Rock Structure and MechanicsCzech Academy of SciencesV Holešovickách 41Prague 18209Czech Republic Institute of Anatomy First Faculty of MedicineCharles UniversityU Nemocnice 3Prague 12800Czech Republic Biomedical Center Faculty of Medicine in PilsenCharles UniversityAlej Svobody 76Pilsen 32300Czech Republic Department of Pathological Physiology Faculty of Medicine in PilsenCharles UniversityAlej Svobody 7632300 PilsenCzech Republic Department of Histology and Embryology Faculty of Medicine in PilsenCharles UniversityAlej Svobody 7632300 PilsenCzech Republic Institute of Pathology First Faculty of MedicineCharles University and General University Hospital in PragueStudnickova 2Prague 12800Czech Republic Department of Biomaterials and Tissue Engineering Institute of PhysiologyCzech Academy of SciencesVidenska 1083Prague 14200Czech Republic Research Center for Structural.materials National Institute for Materials Science1-2-1 SengenTsukuba 305-0047Japan

magnesium is an excellent material in terms of biocompatibility and its corrosion products can serve as an active source for new bone ***,localized corrosion and H_(2)generation l.mit the potential of mg-based *** low-alloyed mg-Zn wires can strongly reduce probl.ms with large H_(2)bubbles and improve the mechanical properties considerably while maintaining excellent long-term *** pickling and a pol.mer coating can be effectively used to lower the rate of in vivo *** this work,microstructural.mechanical,and in vitro characterization of 250μm and 300μm extruded wires made from ultra-pure mg,commercially pure mg,mg-0.15Zn,mg-0.4Zn and mg-1Zn was ***,mg-0.4Zn wires together with a variant coated with a copol.mer of l-lactide andε-caprolactone were tested in vivo on artificially damaged Wistar rat *** on the observed mg-induced osteogenesis,pol.mer-coated mg wires with a small addition of Zn are a perspective material for bone-support applications,such as cerclage and fixation wires.

关键词： magnesium Resorbable mg wire mg-Zn implant degradation Biocompatibility study Zn grain boundary segregation

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