1,552 research outputs found

    Lack of correlation between constitutive and induced resistance to a herbivore in crucifer plants: real or flawed by experimental methods?

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    The correlation between constitutive and induced resistance to herbivores in plants has long been of interest to evolutionary biologists, and various approaches to determining levels of resistance have been used in this field of research. In this study, we examined the relationship between constitutive and induced resistance to the diamondback moth, Plutella xylostella (L.) (Lepidoptera: Plutellidae), in 11 closely related species of wild crucifers. We assessed the survival, development, and reproduction of the test insects and calculated their intrinsic rate of increase as an indicator of constitutive and induced resistance for the plants. We used larvae of P. xylostella and jasmonic acid as elicitors of the induced response. We failed to find a correlation between constitutive and induced resistance in these crucifer plants when the induction of resistance was initiated by either herbivory or jasmonic acid application. Analysis of the results suggests that the failure to detect a relationship between the two types of resistance could be caused by flaws in measuring constitutive resistance, which was apparently confounded with induced resistance. We discuss the difficulties and pitfalls in measuring constitutive resistance and ways to improve the methodology in investigating the relationships between constitutive and induced resistance in plant

    Possible S-wave Dibaryons in SU(3) Chiral Quark Model

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    In the framework of the SU(3) chiral quark model, the Sβˆ’S-wave baryon-baryon bound states are investigated. It is found that according to the symmetry character of the system and the contributions from chiral fields, there are three types of bound states. The states of the first type, such as [ΩΩ](0,0)[\Omega\Omega]_{(0,0)} and [Ξžβˆ—Ξ©](0,1/2)[\Xi^{*}\Omega]_{(0,1/2)} are deeply bound dibaryon with narrow widths. The second type states, [Ξ£βˆ—Ξ”](0,5/2)[\Sigma^{*} \Delta]_{(0,5/2)},[Ξ£βˆ—Ξ”](3,1/2)[\Sigma^{*} \Delta]_{(3,1/2)}, [ΔΔ](0,3)[\Delta\Delta]_{(0,3)} and [ΔΔ](3,0)[\Delta\Delta]_{(3,0)} are also bound states, but with broad widths. [ΞžΞ©βˆ’Ξžβˆ—Ξ©](1,1/2)[\Xi\Omega - \Xi^{*}\Omega]_{(1,1/2)}, [ΞΞ](0,1)[\Xi\Xi]_{(0,1)}, and [NΞ©](2,1/2)[N \Omega]_{(2,1/2)} are third type states. They, like {\em d}, are weakly bound only if the chiral fields can provide attraction between baryons.Comment: Latex files, 1 figur

    Deltaron Dibaryon Structure in Chiral SU(3) Quark Model

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    We discuss the structure of Deltaron dibaryon in the chiral SU(3) quark model. The energy of Deltaron is obtained by considering the coupling of the ΔΔ\Delta\Delta and CCCC (hidden color) channels. The effects of various parameters on the Deltaron mass are also studied. It is shown that the mass of Deltaron is lower than the mass of ΔΔ\Delta\Delta but higher than the mass of Ξ”NΟ€\Delta N \pi.Comment: 15 pages, Late

    Dynamic effects of electromagnetic wave on a damped two-level atom

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    We studied the dynamic effects of an electromagnetic(EM) wave with circular polarization on a two-level damped atom. The results demonstrate interesting ac Stark split of energy levels of damped atom. The split levels have different energies and lifetimes, both of which depend on the interaction and the damping rate of atom. When the frequency of the EM wave is tuned to satisfy the resonance condition in the strong coupling limit, the transition probability exhibits Rabi oscillation. Momentum transfer between atom and EM wave shows similar properties as the transition probability under resonance condition. For a damped atom interacting with EM field, there exists no longer stable state. More importantly, if the angular frequency of the EM wave is tuned the same as the atomic transition frequency and its amplitude is adjusted appropriately according to the damping coefficients, we can prepare a particular 'Dressed State' of the coupled system between atom and EM field and can keep the system coherently in this 'Dressed state' for a very long time. This opens another way to prepare coherent atomic states.Comment: latex, 2 figure

    Magnetic shielding properties of GdBCO bulks with different crystal orientation

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    AbstractHigh-temperature bulk superconductors have significant potential for superconductivity applications. For this paper, the magnetic shielding properties of GdBCO bulk with different crystal orientations were investigated at different temperatures for the purpose of determining its application as field concentrators. Four discs with a diameter of 20mm and thickness of 5mm were cut from the GdBCO single domain. In two discs, the c-axis of crystal was parallel to the disc radius, and, in the others, the c-axis was perpendicular to it. The magnetic shielding effects in a couple of bulks with a gap of 2mm were measured in background fields up to 11 T. The magnetic fields were measured at the center and edge points between the two bulks at LN2, LHe, and temperatures controlled with a cryocooler. In LHe, the discs whose c-axes were parallel to the external magnetic fields maintained a zero field up to 11 T. Even in LN2, the field was shielded to 1 T. The results confirmed the strong magnetic shield effects of GdBCO bulk and can be used for the design of a field concentrator

    Development Of A Cathode Designing Method To Avoid Electrodes’ Interference During Blisk Electrochemical Machining

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    Electrochemical machining plays a prominent role in blisk (bladed integrated disk) construction process. Since blisk channel is narrow and twisted, interference between electrodes may happen during electrochemical machining. Therefore, this paper develops a cathode designing method to avoid interference. Firstly, according to theory of electrochemical machining, machined channel is predicted by calculation. Second, with this channel, interference analysis is carried out and a cathode is designed. Finally, the cathode is employed in experiment and no interference appears

    N-N Interactions in the Extended Chiral SU(3) Quark Model

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    The chiral SU(3) quark model is extended to include coupling between vector chiral field and quarks. By using this model, the phase shifts of NN scattering for different partial waves are studied. The results are very similar to those of the chiral SU(3) quark model calculation, in which one gluon exchange (OGE) plays dominate role in the short range part of the quark-quark interactions. Only in the 1S0^1S_0 case, the one channel phase shifts of the extended chiral SU(3) quark model are obviously improved.Comment: 15 pages, 6 figure

    Risk Factors of Secondary Accidents Based on the Bayesian Hierarchical Model

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    SU(2)-in-SU(1,1) Nested Interferometer for Highly Sensitive, Loss-Tolerant Quantum Metrology

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    We present experimental and theoretical results on a new interferometer topology that nests a SU(2) interferometer, e.g., a Mach-Zehnder or Michelson interferometer, inside a SU(1,1) interferometer, i.e., a Mach-Zehnder interferometer with parametric amplifiers in place of beam splitters. This SU(2)-in-SU(1,1) nested interferometer (SISNI) simultaneously achieves high signal-to-noise ratio (SNR), sensitivity beyond the standard quantum limit (SQL) and tolerance to photon losses external to the interferometer, e.g., in detectors. We implement a SISNI using parametric amplification by four-wave mixing (FWM) in Rb vapor and a laser-fed Mach-Zehnder SU(2) interferometer. We observe path-length sensitivity with SNR 2.2 dB beyond the SQL at power levels (and thus SNR) 2 orders of magnitude beyond those of previous loss-tolerant interferometers. We find experimentally the optimal FWM gains and find agreement with a minimal quantum noise model for the FWM process. The results suggest ways to boost the in-practice sensitivity of high-power interferometers, e.g., gravitational wave interferometers, and may enable high-sensitivity, quantum-enhanced interferometry at wavelengths for which efficient detectors are not available.Comment: 6 pages + 4 of supplemental material, 5 figure

    Plasmid encoding matrix protein of vesicular stomatitis viruses as an antitumor agent inhibiting rat glioma growth in situ

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    Aim: Oncolytic effect of vesicular stomatitis virus (VSV) has been proved previously. Aim of the study is to investigate glioma inhibition effect of Matrix (M) protein of VSV in situ. Materials and Methods: A recombinant plasmid encoding VSV M protein (PM) was genetically engineered, and then transfected into cultured C6 gliomas cells in vitro. C6 transfected with Liposome-encapsulated PM (LEPM) was implanted intracranially for tumorigenicity study. In treatment experiment, rats were sequentially established intracranial gliomas with wild-typed C6 cells, and accepted LEPM injection intravenously. Possible mechanism of M protein was studied by using Hoechst staining, PI-stained flow cytometric analysis, TUNEL staining and CD31 staining. Results: M protein can induce generous gliomas lysis in vitro. None of the rats implanted with LEPM-treated cells developed any significant tumors, whereas all rats in control group developed tumors. In treatment experiment, smaller tumor volume and prolonged survival time was found in the LEPM-treated group. Histological studies revealed that possible mechanism were apoptosis and anti-angiogenesis. Conclusion: VSV-M protein can inhibit gliomas growth in vitro and in situ, which indicates such a potential novel biotherapeutic strategy for glioma treatment.ЦСль: ΠΈΠ·ΡƒΡ‡ΠΈΡ‚ΡŒ ΡΠΏΠΎΡΠΎΠ±Π½ΠΎΡΡ‚ΡŒ матриксного ΠΏΡ€ΠΎΡ‚Π΅ΠΈΠ½Π° (М ΠΏΡ€ΠΎΡ‚Π΅ΠΈΠ½Π°) вируса вСзикулярного стоматита (Π’Π’Π‘) ΡƒΠ³Π½Π΅Ρ‚Π°Ρ‚ΡŒ рост Π³Π»ΠΈΠΎΠΌΡ‹ in situ. ΠœΠ°Ρ‚Π΅Ρ€ΠΈΠ°Π»Ρ‹ ΠΈ ΠΌΠ΅Ρ‚ΠΎΠ΄Ρ‹: сконструирована рСкомбинантная ΠΏΠ»Π°Π·ΠΌΠΈΠ΄Π°, ΠΊΠΎΠ΄ΠΈΡ€ΡƒΡŽΡ‰Π°Ρ М ΠΏΡ€ΠΎΡ‚Π΅ΠΈΠ½ Π’Π’Π‘, которая Π·Π°Ρ‚Π΅ΠΌ Π±Ρ‹Π»Π° трансфСцирована Π² ΠΊΡƒΠ»ΡŒΡ‚ΠΈΠ²ΠΈΡ€ΠΎΠ²Π°Π½Π½Ρ‹Π΅ ΠΊΠ»Π΅Ρ‚ΠΊΠΈ Π³Π»ΠΈΠΎΠΌΡ‹ Π‘6 in. ΠšΠ»Π΅Ρ‚ΠΊΠΈ Π³Π»ΠΈΠΎΠΌΡ‹ Π‘6, трансфСцированныС инкапсулированным Π² липосомы М ΠΏΡ€ΠΎΡ‚Π΅ΠΈΠ½ΠΎΠΌ (Π›Π˜ΠœΠŸ), ΠΈΠΌΠΏΠ»Π°Π½Ρ‚ΠΈΡ€ΠΎΠ²Π°Π»ΠΈ ΠΈΠ½Ρ‚Ρ€Π°ΠΊΡ€Π°Π½ΠΈΠ°Π»ΡŒΠ½ΠΎ для изучСния туморогСнности. Π’ экспСримСнтС крысам с трансплантированной ΠΈΠ½Ρ‚Ρ€Π°ΠΊΡ€Π°Π½ΠΈΠ°Π»ΡŒΠ½ΠΎ Π³Π»ΠΈΠΎΠΌΠΎΠΉ Π‘6 (исходный ΡˆΡ‚Π°ΠΌΠΌ) Π²Π½ΡƒΡ‚Ρ€ΠΈΠ²Π΅Π½Π½ΠΎ Π²Π²ΠΎΠ΄ΠΈΠ»ΠΈ Π›Π˜ΠœΠŸ. АпоптотичСскоС дСйствиС М ΠΏΡ€ΠΎΡ‚Π΅ΠΈΠ½Π° Π½Π° ΠΎΠΏΡƒΡ…ΠΎΠ»Π΅Π²Ρ‹Π΅ ΠΊΠ»Π΅Ρ‚ΠΊΠΈ ΠΈΠ·ΡƒΡ‡Π°Π»ΠΈ с ΠΏΡ€ΠΈΠΌΠ΅Π½Π΅Π½ΠΈΠ΅ΠΌ флуорСсцСнцСнтной микроскопии (ΠΎΠΊΡ€Π°ΡˆΠΈΠ²Π°Π½ΠΈΠ΅ ΠΏΠΎ Π₯Схсту), ΠΏΡ€ΠΎΡ‚ΠΎΡ‡Π½ΠΎΠΉ Ρ†ΠΈΡ‚ΠΎΠΌΠ΅Ρ‚Ρ€ΠΈΠΈ (ΠΎΠΊΡ€Π°ΡˆΠΈΠ²Π°Π½ΠΈΠ΅ ΠΏΡ€ΠΎΠΏΠΈΠ΄ΠΈΡƒΠΌΠΎΠΌ ΠΉΠΎΠ΄ΠΈΠ΄ΠΎΠΌ), TUNEL Π²Π°ΡΠΊΡƒΠ»ΡΡ€ΠΈΠ·Π°Ρ†ΠΈΡŽ ΠΎΠΏΡƒΡ…ΠΎΠ»ΠΈ ΠΎΡ†Π΅Π½ΠΈΠ²Π°Π»ΠΈ гистологичСски ΠΈ Π²Π°ΡΠΊΡƒΠ»ΡΡ€ΠΈΠ·Π°Ρ†ΠΈΡŽ ΠΎΠΏΡƒΡ…ΠΎΠ»ΠΈ ΠΎΡ†Π΅Π½ΠΈΠ²Π°Π»ΠΈ гистологичСски ΠΈ иммуногистохимичСски с ΠΏΡ€ΠΈΠΌΠ΅Π½Π΅Π½ΠΈΠ΅ΠΌ Π°Π½Ρ‚ΠΈ-CD31 ΠΌΠΎΠ½ΠΎΠΊΠ»ΠΎΠ½Π°Π»ΡŒΠ½Ρ‹Ρ… Π°Π½Ρ‚ΠΈΡ‚Π΅Π». 31 ΠΌΠΎΠ½ΠΎΠΊΠ»ΠΎΠ½Π°Π»ΡŒΠ½Ρ‹Ρ… Π°Π½Ρ‚ΠΈΡ‚Π΅Π». 31 ΠΌΠΎΠ½ΠΎΠΊΠ»ΠΎΠ½Π°Π»ΡŒΠ½Ρ‹Ρ… Π°Π½Ρ‚ΠΈΡ‚Π΅Π». Π Π΅Π·ΡƒΠ»ΡŒΡ‚Π°Ρ‚Ρ‹: М ΠΏΡ€ΠΎΡ‚Π΅ΠΈΠ½ ΠΌΠΎΠΆΠ΅Ρ‚ ΠΈΠ½Π΄ΡƒΡ†ΠΈΡ€ΠΎΠ²Π°Ρ‚ΡŒ лизис ΠΊΠ»Π΅Ρ‚ΠΎΠΊ Π³Π»ΠΈΠΎΠΌΡ‹ in. Ни Ρƒ ΠΎΠ΄Π½ΠΎΠ³ΠΎ ΠΆΠΈΠ²ΠΎΡ‚Π½ΠΎΠ³ΠΎ с трансплантированными ΠΊΠ»Π΅Ρ‚ΠΊΠ°ΠΌΠΈ Π³Π»ΠΈΠΎΠΌΡ‹, ΠΎΠ±Ρ€Π°Π±ΠΎΡ‚Π°Π½Π½Ρ‹ΠΌΠΈ Π›Π˜ΠœΠŸ, Π½Π΅ Π²ΠΎΠ·Π½ΠΈΠΊΠ°Π»ΠΈ ΠΎΠΏΡƒΡ…ΠΎΠ»ΠΈ Π·Π½Π°Ρ‡ΠΈΡ‚Π΅Π»ΡŒΠ½ΠΎΠ³ΠΎ Ρ€Π°Π·ΠΌΠ΅Ρ€Π°, Ρ‚ΠΎΠ³Π΄Π° ΠΊΠ°ΠΊ Ρƒ всСх крыс ΠΈΠ· ΠΊΠΎΠ½Ρ‚Ρ€ΠΎΠ»ΡŒΠ½ΠΎΠΉ Π³Ρ€ΡƒΠΏΠΏΡ‹ ΠΎΠΏΡƒΡ…ΠΎΠ»ΠΈ Ρ€Π°Π·Π²ΠΈΠ²Π°Π»ΠΈΡΡŒ. Π’ Π³Ρ€ΡƒΠΏΠΏΠ΅ ΠΆΠΈΠ²ΠΎΡ‚Π½Ρ‹Ρ…, ΠΊΠΎΡ‚ΠΎΡ€Ρ‹ΠΌ Π²Π²ΠΎΠ΄ΠΈΠ»ΠΈ Π›Π˜ΠœΠŸ, ΠΎΠΏΡƒΡ…ΠΎΠ»ΠΈ Π±Ρ‹Π»ΠΈ мСньшСго объСма ΠΈ ΠΎΡ‚ΠΌΠ΅Ρ‡Π°Π»ΠΈ ΡƒΠ²Π΅Π»ΠΈΡ‡Π΅Π½ΠΈΠ΅ ΠΏΡ€ΠΎΠ΄ΠΎΠ»ΠΆΠΈΡ‚Π΅Π»ΡŒΠ½ΠΎΡΡ‚ΠΈ ΠΆΠΈΠ·Π½ΠΈ ΠΆΠΈΠ²ΠΎΡ‚Π½Ρ‹Ρ…. Показано, Ρ‡Ρ‚ΠΎ М ΠΏΡ€ΠΎΡ‚Π΅ΠΈΠ½ проявляСт Π°Π½Ρ‚ΠΈΠ°Π½Π³ΠΈΠΎΠ³Π΅Π½Π½Ρ‹Π΅ свойства ΠΈ ΠΎΠ±Π»Π°Π΄Π°Π΅Ρ‚ ΡΠΏΠΎΡΠΎΠ±Π½ΠΎΡΡ‚ΡŒΡŽ ΠΈΠ½Π΄ΡƒΡ†ΠΈΡ€ΠΎΠ²Π°Ρ‚ΡŒ Π°ΠΏΠΎΠΏΡ‚ΠΎΠ·. Π’Ρ‹Π²ΠΎΠ΄Ρ‹: М ΠΏΡ€ΠΎΡ‚Π΅ΠΈΠ½ Π’Π’Π‘ ΠΈΠ½Π³ΠΈΠ±ΠΈΡ€ΡƒΠ΅Ρ‚ рост Π³Π»ΠΈΠΎΠΌΡ‹ in ΠΈ in. На этой основС ΠΌΠΎΠΆΠ΅Ρ‚ Π±Ρ‹Ρ‚ΡŒ Ρ€Π°Π·Ρ€Π°Π±ΠΎΡ‚Π°Π½Π° ΠΏΠΎΡ‚Π΅Π½Ρ†ΠΈΠ°Π»ΡŒΠ½ΠΎ новая биотСрапСвтичСская стратСгия для лСчСния ΠΏΠ°Ρ†ΠΈΠ΅Π½Ρ‚ΠΎΠ² с Π³Π»ΠΈΠΎΠΌΠ°ΠΌΠΈ
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