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We develop a well-posed multiparticle Coulomb scattering problem based on asymptotic solutions of a Coulomb multichannel scattering problem constructed in the adiabatic representation. A key feature of the studied problem is that the nonadiabatic channel coupling matrix is nontrivial at large internuclear distances. We consider the scattering problem in the case with an arbitrary momentum value and study solutions for small channel coupling matrix values in detail, constructing explicit representations for the asymptotic solution of the scattering problem.

2-Arachidonoylglycerol (2-AG) is acting as a full agonist of cannabinoid receptor 1 and 2. Direct manipulation of 2-AG levels is a challenging task. The amphiphilic properties and the instability of 2-AG in aqueous media complicate its use as a drug-like molecule. Additionally, inhibition of the protein machinery that regulates 2-AG levels may also affect other monoacylglycerols. Therefore, we developed a novel method to elevate 2-AG levels with a flash of light. The resulting tool is a photoactivatable "caged" 2-arachidonoylglycerol (cg2-AG) allowing for the rapid photorelease of the signaling lipid in live cells. We characterized the mechanism of uncaging and the effect of 2-AG on the regulation of the β-cell signaling network. After uncaging of 2-AG, we monitored calcium levels, CB1-GIRK channel coupling, and CB1-mediated inhibition of adenylate cyclase and protein kinase A activity.

This paper examined the fusion of 28Si with 90,96Zr-target by opting the energy dependent Woods-Saxon potential (EDWSP) model and code CCFULL. The CCFULL analysis suggested that for 28Si + 90Zr system, the vibrational excitations of 90Zr-isotope have been found to be very important while for 28Si + 96Zr system, in addition to multiphoton vibrational states of target, the considerations of nucleon transfer are essentially needed for the adequate addressal of the observed fusion data. In contrast, predictions based on EDWSP model appropriately recovered the fusion data of 28Si + 90,96Zr systems at sub-barrier realm. The EDWSP based results do not include various channel coupling effects explicitly but being the energy dependent nature of Woods-Saxon potential (WSP), the calculational results intrinsically incorporate the nuclear effects of the fusing systems. This unambiguously clarified that the energy dependent nature of the EDWSP generates analogous barrier modulations as emerged from the CCFULL analysis.

28 nm FD-SOI technology is electrically characterized aiming at cryogenic applications. Electrostatics and transport are evaluated and compared while lowering temperature from 300 K down to 4.2 K. FD-SOI versatility is shown over a wide temperature range of operation, as the back gate tuning efficiency is preserved at low temperatures. Insights on back gate bias behavior at room and low temperatures are obtained and the electrostatic coupling between front and back channels can be successfully modelled by using 1D Poisson-Schrodinger calculation from 300 K down to 4.2 K.

Inspired by the recent report of the exotic states $X_{0}(2900)$ and $X_{1}(2900)$ with four different quark flavors in the $D^{-}K^{+}$ invariant mass distributions of the decay process $B^{+}\rightarrow D^{+}D^{-}K^{+}$ by the LHCb collaboration, we systematically investigate the tetraquarks composed of $ud\bar{s}\bar{c}$ with meson-meson and diquark-antidiquark structures in the quark delocalization color screening model. We find that the $X_{0}(2900)$ can be interpreted as the molecular state $\bar{D^{*}}K^{*}$ with $IJ^{P}=00^{+}$. Moreover, two bound states are obtained by the channel coupling calculation, with energies $2341.2$ MeV for $IJ^{P}=00^{+}$ and $2489.7$ MeV for $IJ^{P}=01^{+}$, respectively. We also extend our study to the $uc\bar{d}\bar{s}$ systems and find that there is no any bound state, so the $D_{s0}(2317)$ cannot be identified as the $DK$ molecular state in present calculation. Besides, several resonance states with the diquark-antidiquark configuration are possible in both $ud\bar{s}\bar{c}$ and $uc\bar{d}\bar{s}$ systems. All these open charm bound states and resonances are worth searching in the future experiments., 8 pages, 2 figures. arXiv admin note: text overlap with arXiv:1902.05778

In order to improve the signal natural frequency of dynamic vibration absorber and eliminate the influence of nonlinear output force to the adaptive vibration absorption system. A new type of electromagnetic active vibration absorber is designed in this article. The internal magnetic circuit structure is changed through the electromagnet placed on the upper and lower, produce the electromagnetic force in two directions. Reaction force of upper mass is used to eliminate the target vibration. The effective frequency range of the vibration absorption increases, output force is basically linear. Aimed at multiple-point adaptive control strategy, a distributed multi-channel adaptive control algorithm is proposed, in which coupling between channels can be compensated on each control loop. Influence of secondary path on active control is analyzed, put forward the improved least mean square algorithm to identify the secondary. Active vibration control experiment platform is structured to verify the output force of absorber, and engineering application of the distributed multi-channel adaptive control algorithm. The results show that the distributed multi-channel adaptive control algorithm system has about 15 dB noise reduction, effect is obvious; new type of electromagnetic active vibration absorber is not limited to the natural frequency, output force can adaptive keep pace with the excitation frequency.

Author(s): Michaelides, Katerina; Hollings, Rory; Singer, Michael Bliss; Nichols, Mary H; Nearing, Mark A

A previously reported normally-off GaN double-channel (DC-) MOS-HEMT with a gate recess into the upper channel layer has achieved a remarkably low ${R}_{\text {on}}$ . In this letter, we found that the double-channel structure itself does not guarantee a low ${R}_{\text {on}}$ without careful consideration of the electrical coupling between the two channels. A strong channel-to-channel (C2C) coupling between the two channels is critical to reduce ${R}_{\text {on}}$ in the DC-MOS-HEMT by exploiting both channels at the access region while allowing currents to converge into the heterojunction lower channel at the gate region. Otherwise, with a weak C2C coupling, the conduction through the upper channel is comprised due to the high-resistivity MOS-channel section at the gate region. The fabricated DC-MOS-HEMT with C2C distance ( ${t}_{{\textsf {C2C}}}$ ) of 7.5 nm exhibits an appreciably lower ${R}_{\text {on}}$ than that with ${t}_{{\textsf {C2C}}} = \textsf {11.5}$ nm. Further analysis reveals the latter suffers from an increased sheet resistance at access region compared with the sheet resistance of the DC-heterostructure itself. A modified TLM characterization is proposed to analyze the C2C coupling in the DC-heterostructure. It is confirmed the DC-heterostructure with ${t}_{{\textsf {C2C}}} = \textsf {7.5}$ nm boasts a strong C2C coupling, while that with ${t}_{{\textsf {C2C}}} = \textsf {11.5}$ nm features relatively weak C2C coupling.

The formalism of the coupled $q\bar q$ and the $\varphi\varphi ( \pi-\pi$, $K\bar K, \pi K,...$) scalar channels is formulated, taking into account the ground and radial excited $q\bar q$ poles. The basic role is shown to be played by the transition coefficients $k^{(I)} (q\bar q, |\varphi\varphi)$, which are calculated using the quark-chiral Lagrangian without free parameters. The resulting method, called the pole projection mechanism (PPM), ensures: 1) one resonance for each $\varphi\varphi$ channel from the basic $q\bar q$ pole, e.g. the $f_0 (500)$ resonance in the $\pi\pi$ channel; 2) a possibility to have two $\varphi\varphi$ resonances, coupled to the same $q\bar q$ state, when the channel coupling is taken into account in the meson-meson channels, which yields $f_0 (500)$ and $f_0(980)$ from the same $n\bar n$ pole around 1 GeV; 3) the strong pole shift down for special ($\pi\pi, \pi K)$ channels due to large transition coefficients $k^{(I)}$, computed in this formalism without free parameters. The parameters of calculated complex poles are in reasonable agreement with the experimental data of the resonances $f_0(500)$, $f_0(980)$, $a_0(980)$, $a_0(1450)$, $K^*_0(700)$, $K^*_0(1430)$, $f_0(1370)$ and $f_0(1710)$., Comment: v2: 22 pages, 5 figures; new explanations are added, several important insertions are made, the list of references is enlarged

The coupled system was studied to investigate whether the inclusion of channel coupling is able to bind the system. We use a separable potential three-body model of the coupled system and a variational four-body calculation with realistic interactions. Our results exclude the possibility of a bound state by a large margin. Instead, we found a quasibound state above the threshold.

The dipion transitions ϒ(2S,3S,4S)→ϒ(1S,2S)ππ are systematically studied by considering the mechanisms of the hadronization of soft gluons, exchanging the bottomoniumlike Zb states, and the bottom-meson loops. The strong pion-pion final-state interaction, especially including the channel coupling to KK¯ in the S-wave, is taken into account in a model-independent way using the dispersion theory. Through fitting to the available experimental data, we extract values of the transition chromopolarizabilities |αϒ(mS)ϒ(nS)|, which measure the chromoelectric couplings of the bottomonia with soft gluons. It is found that the Zb exchange has a slight impact on the extracted chromopolarizablity values, and the obtained |αϒ(2S)ϒ(1S)| considering the Zb exchange is (0.29±0.20) GeV-3. Our results could be useful in studying the interactions of bottomonium with light hadrons.

The Chiral Confining Lagrangian, based on the chiral theory with quark degrees of freedom, is used to study the spectroscopy of scalar mesons. The formalism does not contain arbitrary fitting parameters and takes into account infinite number of transitions from meson-meson to quark-antiquark states. Starting from known $q\bar q$ poles the transition coefficients ensure the strong shift of the poles for the $\pi\pi$ and much smaller shift for the $K\bar K$ systems. The resulting amplitudes $f_{\pi\pi}$ and $f_{K\bar K}$ are calculated in terms of the $q\bar q$ and the free meson Green's functions. With the account of the $\pi\pi/K\bar{K}$ channel coupling one obtains two resonances: a wide resonance $E_1$ in the range 500-700 MeV and narrow $E_2 $ near 1 GeV, which can be associated with $f_0(500)$ and $f_0(980)$. A similar analysis, applied to the $I=1$ channel, shows that in this case two very close poles in different sheets appear near $E=980$ MeV, which can be associated with the $a_0 (980)$ resonance. The obtained $\pi\pi$ interaction amplitudes, $\operatorname{Re} f_{\pi\pi} (E)$ and $\operatorname{Im} f_{\pi\pi}(E)$ are compared with the known data., Comment: v5: 29 pages, 6 figures; version accepted to PRD, new equations with explanations are added, several important insertions are made, the list of references is correspondingly enlarged

Synopsis The effect of inner-shell excited channels on outer-shell photodetachment is investigated using a correlated and coupled-channel R-matrix method. The simplest multishell negative ion of Li− is treated near the 1s ionization threshold to determine strong”hole-state” continuum coupling with the direct photodetachment channels.

Two-channel and multichannel thermal unimolecular reactions are analyzed by simple models, starting with the calculation of separated-channel rate constants and accounting for intrinsic channel coupling afterward. Reactions with rigid- and with loose-activated complex channels are distinguished. Weak-collision, energy-transfer, effects are suggested to govern the competition between rigid-activated complex channels, while angular-momentum, “rotational channel switching”, effects dominate the competition between rigid- and loose-activated complex channels. The models are tested against master equation treatments of the dissociations of formaldehyde and of glyoxal from the literature. Besides giving insight into the influence of various molecular input parameters, the present approach leads to compact representations of rate constants suitable for inclusion in databases.

In the framework of the chiral quark model, we investigate the hidden strange pentaquark system of the Nϕ state with quantum numbers of IJP=1232−. The results show that the Nϕ state can be bound through the interaction of the σ meson exchange plus the effect of channel coupling, which means that the effect of channel coupling has an influence on the existence of this bound state.

The glue-like behavior of valence neutrons has been investigated in the Li isotopes. The 7Li nucleus is well known to be weakly bound system with the α + t cluster structure. By adding the valence neutrons, the reduction of the root-mean-square (RMS) radius of the proton density for the 7Li, 8Li and, 9Li nuclei is also well known from the viewpoint of the experimental data and theoretical approach. Elastic scattering cross sections of the Li isotopes on the 12C and 28Si targets at E/A ∼ 50 MeV are calculated. We find the change of the channel coupling (CC) effect on elastic scatterings of such Li isotopes by the glue-like role of the valence neutrons. Finally, we realize that the valence neutrons stabilize the binding of core parts, and the CC effect related the core excitation is indeed reduced., PROCEEDINGS OF THE 4TH INTERNATIONAL WORKSHOP ON “STATE OF THE ART IN NUCLEAR CLUSTER PHYSICS” (SOTANCP4), 13–18 May 2018, Texas, USA.

The specificity and universality of intracellular Ca2+ signals rely on the variety of spatio-temporal patterns that the Ca2+ concentration can display. Ca2+ liberation through inositol 1,4,5-trisphosphate receptors (IP3Rs) is key for this variety. In this paper, we study how the competition between buffers of different kinetics affects Ca2+ signals that involve Ca2+ release through IP3Rs. The study also provides insight into the underlying spatial distribution of the channels that participate in the signals. Previous works on the effects of Ca2+ buffers have drawn conclusions 'indirectly' by observing the Ca2+-bound dye distributions in the presence of varying concentrations of exogenous buffers and using simulations to interpret the results. In this paper, we make visible the invisible by observing the signals simultaneously with two dyes, Rhod-2 and Fluo-4, each of which plays the role of a slow or fast Ca2+ buffer, respectively. Our observations obtained for different concentrations of Fluo-4 highlight the dual role that fast buffers exert on the dynamics, either reducing the intracluster channel coupling or preventing channel inhibition and allowing the occurrence of relatively long cycles of Ca2+ release. Our experiments also show that signals with relatively high Ca2+ release rates remain localized in the presence of large Rhod-2 concentrations, while the mean speed of the elicited waves increases. We interpret this as a consequence of the more effective uncoupling between IP3R clusters as the slow dye concentration increases. Combining the analysis of the experiments with numerical simulations, we also conclude that Ca2+ release not only occurs within the close vicinity of the centers of the clearly identifiable release sites (IP3R clusters) but there are also functional IP3Rs in between them. Fil: Piegari, Estefanía. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Instituto de Física de Buenos Aires. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Instituto de Física de Buenos Aires; Argentina Fil: Lopez, Lucía Fernanda. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Instituto de Física de Buenos Aires. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Instituto de Física de Buenos Aires; Argentina Fil: Ponce Dawson, Silvina Martha. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Instituto de Física de Buenos Aires. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Instituto de Física de Buenos Aires; Argentina

We present an analytical surface potential based model for the induced thermal noise at the gate terminal in High Electron Mobility Transistors, due to gate channel coupling. Our model is applicable to any HEMT device. We also present the results of the validation of our model with experimental data from literature.

Herein, we investigated the channel coupling (CC) effect on the elastic scatterings of lithium (Li) isotopes ($A =$ 6--9) for the $^{12}$C and $^{28}$Si targets at $E/A =$ 50--60 MeV. The wave functions of the Li isotopes were obtained using the stochastic multi-configuration mixing (SMCM) method based on the microscopic-cluster model. The proton radii of the $^{7}$Li, $^{8}$Li, and $^{9}$Li nuclei became smaller as the number of valence neutrons increased. The valence neutrons in the $^{8}$Li and $^{9}$Li nuclei exhibited a glue-like behavior, thereby attracting the $\alpha$ and $t$ clusters. Based on the transition densities derived from these microscopic wave functions, the elastic-scattering cross section was calculated using a microscopic coupled-channel (MCC) method with a complex $G$-matrix interaction. The existing experimental data for the elastic scatterings of the Li isotopes and $^{10}$Be nuclei were well reproduced. The Li isotope elastic cross sections were demonstrated for the $^{12}$C and $^{28}$Si targets at $E/A$ =53 MeV. The glue-like effect of the valence neutrons on the Li isotope was clearly demonstrated by the CC effect on elastic scattering. Finally, we realize that the valence neutrons stabilized the bindings of the core parts and the CC effect related to core excitation was indeed reduced., Comment: 21 pages, 9 figures, 2 tables, accepted in Physical Review C

This study focuses on using a semi-classical and quantum mechanical approach based originally on the theory of Winther and Alder that is used to explain the Coulomb excitation. This approach is called the coupled channels with continuum-discretised (CCCD), where the semi-classical and quantum models were used to investigate the channel coupling effects on the determination of the cross section for fusion σfus (mb) and the distribution of the fusion barrier Dfus (mb/MeV) for systems 14N+59Co, 16O+64Ni and 18O+64Ni. The comparison between the results of the semi-classical and quantum mechanical models along with the corresponding experimental data shows clearly that the adopted semi-classical model is very competitive to the quantum mechanical model and can be considered as efficient approach to study the properties of the fusion reactions.

This dual-ducted SUAV is a nonlinear and strong coupling of multiple-input and multiple-output system, and particularly between the pitch and roll channels channel coupling is strong, in order to implement effective control, it must be decoupled. The traditional methods are difficult to achieve effective control of the strong coupling of multivariable systems. For the SUAV model of nonlinear coupling characteristics, based on the establishment of the UAV attitude model, this paper designed an attitude ADRC decoupling controller. The simulation showed this ADRC decoupling controller had strong robustness and immunity, and solved the channels coupling between the pitch and roll.

[1] Decomposition of horizontally extended current system into components in the polarization processes and extraction of Cowling channel defined in the companion paper embedded in the total current system are numerically demonstrated. We successfully visualize the background and polarization components in the magnetosphere-ionosphere coupling process by using the proposed theoretical framework. As a fundamental response, the polarization charge produced by the Pedersen current divergence has a role to cancel and intensify the ambient background electric field inside and outside the high-conductivity band, respectively. In contrast, the polarization charge produced by the Hall current divergence has a role to rotate the electric field from the background electric field, which causes a meandering of ionospheric convection flow along the boundary of a high-conductivity band. The Hall and Pedersen currents are always perpendicular to each other. They never close each other when conductances are homogeneous, but they can do that at the conductivity gradient region. This is the reason why a Hall polarization charge is induced and a resultant Cowling channel is formed.

The character of riverbed sediments usually reflects fluvial processes and the dynamics of sediment transport in fluvial systems. The approach in this study was based on the measurement of the largest boulders located within a bankfull channel, and on the observation of changes in their size in the longitudinal profile of a headwater stream in the Moravian-Silesian Beskids Mountains. The resulting trends in a particle-size index reflect the character of sediment delivery into channel segments and the recent channel-forming processes. The largest boulders were observed in channel sections with a strong interaction of slope and fluvial processes, and a slight coarsening of sediments was recorded in the incised downstream sections of the longitudinal stream profile. In contrast, the refining of bed sediments was typical of the transitional zone between slope-channel coupled reaches and an alluvial cone characterised by a tendency to material aggradation.

The role of neutron transfer in fusion reactions of weakly-bound nuclei at subbarrier energies is studied within the empirical model of channel coupling. The results from calculating the fusion cross sections for the 7Li + 209Bi, 9, 11Li + 208, 206Pb, 6, 7, 9, 11Li + 152Sm reactions are presented. Good agreement with the available experimental data is shown. Several combinations of colliding nuclei for which the strong enhancement of subbarrier fusion due to the effect of neutron transfer processes are predicted.

Maneuvering of the fighter aerodynamic have certain requirements, this paper for needs of F-16 aircraft maneuvering, according to some existing fighter of the gas dynamic layout and parameters and establish more accurate fighter aerodynamic configuration, internal structure parameters and control input quantity. This paper also introduces the standard atmosphere model and the engine model, and analyzes the control characteristics of the aircraft by verifying the zero input response and channel coupling characteristics, and analyzes the performance of the model. This method can be applied to the performance analysis of other models.

We have analyzed the fusion excitation function data of various heavy ion systems in the near barrier energy region using Wongʼs formula and an energy dependent potential. The various channel coupling effects for different projectile–target combinations are properly mocked up by the energy dependent potential resulting in a very good agreement between the data and the predictions.

The three degree-of-freedom (3-DOF) laboratory helicopter is a typical multiple-input multiple-output system with high order, which has stronger channel coupling and higher non-linearity. The proposed controller is a combination of H2 control, H∞ control and multiple-model weighted control. The controller can be used to minimize the H2 performance index under the condition that H∞ performance index is smaller than a certain constant. In addition, the weights of multiple controllers in the multiple-model control can be adjusted in the real time in flight. In this way, not only can the whole system obtain the compromise between system performance and robust properties, but also the control precision and approximating precision are improved. Experimental results demonstrate the effectiveness of the proposed control strategy.

The role of neutron transfer is investigated in the fusion process near and below the Coulomb barrier within the empirical channel coupling approach. The possibility of neutron transfer with positive Q-values considerably increases the barrier penetrability. The enhancement of fusion cross sections for 58Ni + 64Ni, 32S + 64Ni, 40Ca + 48Ca, and 40Ca + 124Sn is well reproduced at subbarrier energies by the empirical channel coupling approach including the coupling to the neutron-transfer channels. The predictions of the fusion cross sections for several combinations of colliding nuclei are also proposed which may shed additional light on the effect of neutron transfer in fusion processes. A huge enhancement of deep subbarrier fusion probability was found for light neutron-rich weakly bound nuclei. This may be quite important for astrophysical primordial and supernova nucleosynthesis.

Okubo–Zweig–Iizuka-allowed partial decay widths, masses, and total decay width of charmonium states are studied in a nonrelativistic coupled-channel framework based on microscopic effective quark interactions. With the help of the complex scale transformation, the coupled channel equation is easily solved under the proper boundary condition for resonances. The obtained result as a whole is very successful and encouraging for the traditional charmonium states including ψ(4040) whose features of mass and partial decay widths have been argued historically. The coupling mechanisms of these states are investigated by reducing artificially the channel coupling strengths little by little and finally turning the coupling off. The situations turn out to be quite different from what we would have naively supposed. Other solutions than the traditional charmonium states were obatined at the same time. Some of them are discussed in relation with new particles observed recently.

A brief review of the background and theory underlying the channel coupling array (CCA) method for treating n-particle scattering problems and recently applied to very simple atomic and molecular structure problems is given. This is followed by a comparison of CCA calculations with certain variational ones for H2, Hc, and HeH+. The work concludes with a few speculative comments.

Generalization of the R-matrix theory of nuclear reactions with the use of the method of projection operators has been performed to describe the fission and cluster decays of atomic nuclei with the emission of two or three fragments with successive quantum-mechanical consideration of the fission and decay channel coupling.

The dynamic coupling effects on fusion cross sections for reactions $^{32}$S + $^{94,96}$Zr and $^{40}$Ca + $^{94,96}$Zr are studied with the universal fusion function formalism and an empirical coupled channel (ECC) model. An examination of the reduced fusion functions shows that the total effect of couplings to inelastic excitations and neutron transfer channels on fusion in $^{32}$S + $^{94}$Zr ($^{40}$Ca + $^{94}$Zr) is almost the same as that in $^{32}$S + $^{96}$Zr ($^{40}$Ca + $^{96}$Zr). The enhancements of the fusion cross section at sub-barrier energies due to inelastic channel coupling and neutron transfer channel coupling are evaluated separately by using the ECC model. The results show that effect of couplings to inelastic excitations channels in the reactions with $^{94}$Zr as target should be similar as that in the reactions with $^{96}$Zr as target. This implies that the quadrupole deformation parameters $\beta_2$ of $^{94}$Zr and $^{96}$Zr should be similar to each other. However, $\beta_2$'s predicted from the finite-range droplet model, which are used in the ECC model, are quite different. Experiments on $^{48}$Ca + $^{94}$Zr or $^{36}$S + $^{94}$Zr are suggested to solve the puzzling issue concerning $\beta_2$ for $^{94}$Zr., Comment: 8 pages, 5 figures. arXiv admin note: text overlap with arXiv:1504.00756

Measuring transmission between four antennas in microwave cavities, we investigate directly the channel cross-correlations $C$ of the cross sections $\sigma^{ab}$ from antenna at $\vec{r}_a$ to antenna $\vec{r}_b$. Specifically we look for the $C_\Sigma$ and $C_\Lambda$, where the only difference is that $C_\Lambda$ has none of the four channels in common, whereas $C_\Sigma$ has exactly one channel in common. We find experimentally that these two channel cross-correlations are anti-phased as a function of the channel coupling strength, as predicted by theory. This anti-correlation is essential to give the correct values for the universal conductance fluctuations. To obtain a good agreement between experiment and predictions from random matrix theory the effect of absorption had to be included., Comment: 6 pages, 5 figures

An overview of results in fusion studies with stable beams spanning different mass regions and energy ranges is presented. The advantages offered by studying channel coupling effects, involving low-lying excited states of the colliding nuclei, as well as the difficulties in understanding the influence of transfer couplings on fusion, are firstly remarked. The competition of fusion with quasi-fission in heavy systems and the unexpected steep falloff of fusion cross sections at far sub-barrier energies are finally discussed.

International audience; We discuss the role of channel coupling of 28Si on fusion mechanism with permanently deformed target 154Sm. To this end, we analyze the experimental quasi-elastic cross sections at a large backward angle and quasi-elastic barrier distribution for 28Si+154Sm system using the coupled-channels approach. While earlier studies have reported the rotational excitation of 28Si playing role on fusion with spherical and near spherical target nuclei, we find its vibrational excitation as origin of observed barrier distribution for 28Si+154Sm system. Our study also reveals significant influence of channel couplings on the surface diffuseness parameter of an inter-nuclear potential supporting the earlier observations.

Fusion cross sections induced by He and Li were studied using different reactions [(He+Bi, He+Pb, He+Au), (He+Bi, He+Pb, He+Au) and (He+Bi, He+Pb, He+Au)], these reactions were used to determine the influence of the heavy targets on the fusion excitation function mechanism. The reactions [He+Pb, He+Pb, He+Pb] give the same compound nuclei Po and the reactions (He+Bi and Li+Pb) give the same compound nuclei At. These reactions were used to determine the influence of the compound nuclei on fusion excitation function mechanism. Theoretical calculations were done using the Channel Coupling code of the NRV using W. S. Surface with different parameters (Vo, ro, ro, a and ћωβ ) for all reactions. The current study has shown that, large enhancement in the fusion cross sections at energies at the Coulomb barrier were observed only in the reactions He+Pb and He+Pb compared with He+Pb and slightly or no enhancement were observed in the reactions He+Bi and He+Au compared with reactions induced by He.

This paper presents a new dual-slope-based time-interleaved quantizer architecture. Time information between interleaved quantizer channels is utilized to perform time-domain delta modulation. This technique decouples the conversion rate of dual-slope quantizers from their input voltage amplitude without the need for extra timing phases or dedicated hardware.

The close coupling (CC) equations in the impact parameter (IP) representation are considered. Calculations for transitions in the 3s–3p–3d He atom system induced by collisions with single charged ions were carried out. Results are compared with those obtained in the frame of the Born approach. The effects of stepped transitions, normalization, channel coupling and their dependence on interaction strength are discussed.

Charmed (and bottom) hypernuclei are studied in the quark–meson coupling (QMC) model. This completes systematic studies of charmed (Λ+c, Σc, Ξc), and Λb hypernuclei in the QMC model. Effects of the Pauli blocking due to the underlying quark structure of baryons, and the ΣcN–ΛcN channel coupling are phenomenologically taken into account at the hadronic level in the same way as those included for strange hypernuclei. Our results suggest that the Σ++c and Ξ+c hypernuclei are very unlikely to be formed, while the Λ+c, Ξ0c and Λb hypernuclei are quite likely to be formed. For the Σ+c hypernuclei, the formation probability is non-zero, though small. A detailed analysis is also made about the phenomenologically introduced Pauli blocking and channel coupling effects for the Σ0c hypernuclei.

We report the effects of collision energy (E c o l ) and five different H 2 CO + vibrational modes on reaction of H 2 CO + with ND 3 and D 2 O over the center-of-mass E c n l range from 0.1 to 2.1 eV. Properties of various complexes and transition states were also examined computationally. For water, the only reaction is proton transfer (PT), going by a direct mechanism over the entire E c o l range, with a cross section near the collision limit. H 2 CO + vibrational excitation has no effect on reaction with water. Three product channels are observed in reaction with ammonia. Both proton transfer (PT) and charge transfer (CT) have large cross sections over the entire energy range. Hydrogen abstraction by H 2 CO + from ammonia (HA) accounts for

The fusion barrier distribution has provided a nice representation for the channel coupling effects on heavy-ion fusion reactions at energies around the Coulomb barrier. Here we discuss how one can extract the same representation using the so called sum-of-differences (SOD) method with quasi-elastic scattering cross sections. In contrast to the conventional quasi-elastic barrier distribution, the SOD barrier distribution has an advantage in that it can be applied both to non-symmetric and symmetric systems. It is also the case that the correspondence to the fusion barrier distribution is much better than the quasi-elastic barrier distribution. We demonstrate its usefulness by studying $^{16}$O+$^{144}$Sm, $^{58}$Ni+$^{58}$Ni, and $^{12}$C+$^{12}$C systems., 6 pages, 9 figures. A talk given at VI International Conference FUSION14, Feb. 24-28, 2014, New Delhi, India

Resonating-group method has been applied to calculate the dibaryon state in the framework of the extended quark-delocalization color-screening model. The mass of the di-Ω is predicted to be about 45 MeV lower than the threshold. The effect of channel coupling due to the tensor force and sensitivity to meson exchange short-range cutoff radius, have also been studied.

A new two-dimensional hydrological model has been developed that accounts for dynamic interactions between hillslope and channel flows. The model is specifically designed for semi-arid areas dominated by Hortonian overland flow, and has a dynamically active channel belt. Sensitivity analyses of the model have been carried out to assess the relative importance of topographic linkages, surface characteristics and rainfall characteristics on catchment hydrological response. Attribute sensitivity analyses suggest that hillslopes are more sensitive than floodplains to all parameters except surface roughness. However, decoupling through the presence of floodplains or other barriers will reduce the relative importance of the sensitivity of hillslope parameters. Spatial sensitivity analysis suggests that sensitivity to the spatial variability of infiltration decreases with an increase in the magnitude of the runoff event. On the other hand, variability in output discharge at the catchment outlet increases with an increase in the spatial variability of infiltration. Rainfall intensity is thus an important factor in controlling the overall coupling characteristics. Catchment runoff production is affected by a complex interaction of topographic, surface and rainfall characteristics. Copyright © 2002 John Wiley & Sons, Ltd.

Background: Of the two sources of nonlocality in nucleon-nucleus and nucleus-nucleus interactions, knock-on exchange and dynamically generated, almost all papers referring to nonlocality mention only the first.\ud \ud Purpose: Our purpose is threefold: to demonstrate a method for including dynamical nonlocality, for which a simple prescription (like the Perey factor for exchange nonlocality) is unknown, within distorted wave Born approximation (DWBA) calculations; to identify signatures of dynamic nonlocality and illuminate the extent to which the presence of such nonlocality can influence the extraction of spectroscopic information from direct reactions, and more generally, to increase our understanding of nucleus-nucleus interactions.\ud \ud Methods: After reviewing existing indications of dynamically induced nonlocality, DWBA transfer calculations are presented which compare results involving dynamically nonlocal potentials with those involving their local equivalents. The dynamical nonlocal potentials are generated in situ by the presence of channel coupling and the local equivalents are generated by inversion of the corresponding coupled channel elastic S matrix. This method obviates the need for solving integro-differential equations for including nonlocal potentials in DWBA.\ud Results: The coupling of nucleons to collective states of the target nucleus induces dynamical nonlocality in the nucleon-nucleus interaction that has a significant effect on (p,d) reactions at energies relevant to spectroscopic studies.\ud \ud Conclusions: A method for studying the contribution of dynamically induced nonlocality in nuclear interactions has been demonstrated. Dynamically induced nonlocality should not be overlooked in the analysis of direct reactions. The method can also be applied to dynamic nonlocality due to projectile excitation.

The rates of RNA synthesis and nascent RNA folding into biologically active structures are linked via pausing by RNA polymerase (RNAP). Structures that form within the RNA exit channel can increase pausing by interacting with bacterial RNAP or decrease pausing by preventing backtracking. Conversely, pausing is required for proper folding of some RNAs. Opening of the RNAP clamp domain is proposed to mediate some effects of nascent RNA structures. However, the connections among RNA structure formation, clamp movement, and catalytic activity remain uncertain. We assayed exit-channel structure formation in Escherichia coli RNAP together with disulfide crosslinks that favor closed or open clamp conformations and found that clamp position directly influences RNA structure formation and catalytic activity. We report that exit-channel RNA structures slow pause escape by favoring clamp opening and through interactions with the flap that slow translocation.

The total fusion (TF) excitation function for a $^{6}\mathrm{Li}$ projectile with a $^{64}\mathrm{Ni}$ target has been measured using the online characteristic $\ensuremath{\gamma}$ ray detection method at energies around the Coulomb barrier. The complete fusion (CF) excitation function for the system is subsequently estimated from the dominating neutron evaporation channels with the help of statistical model predictions. The CF cross sections exhibit a suppression of about $13%$ compared to the one-dimensional barrier penetration model (1DBPM) at above-barrier energies, but no suppression is observed for TF cross sections. The observation does corroborate the estimated suppression for $^{6}\mathrm{Li}$ on $^{59}\mathrm{Co}$ target, but does not corroborate the recently proposed universal suppression factor for the $^{6}\mathrm{Li}$ projectile. The result supports the conjecture of reduced suppression of CF cross sections with decreasing target mass. At energies below the barrier, both the TF and the CF cross sections are enhanced. The observed enhancement of the CF process can be explained by channel coupling (CC), but the enhancement in TF cross sections is significantly higher than the CC predictions.

In the framework of the chiral quark model, the mass spectrum of χ cJ (J = 0, 1, 2, n = 1, 2, 3) is studied with the Gaussian expansion method. Using the wave functions obtained in the study of mass spectrum, the open charm two-body strong decay widths of these states are calculated by using the 3 P 0 model. The results show that the masses of χ cJ (1P) and χ c2(2P) are consistent with the experimental data. But the strong decay width of χ c2(2P) is three times that of the experimental value. The decay width of χ c1(2P) is sensitive to its mass. In the quark-antiquark picture, the width is about 385 MeV. However, if the channel coupling effects shift its mass to 3872 MeV, its decay width will be around 1 MeV. The possibility of assigning the state X(3872) as χ c1(2P) cannot be excluded. To assign X(3915) as χ c0(2P) is disfavored, due to the unmatching of decay channel. For the χ cJ (3P) states, no states have been assigned. The possible candidates of χ c0(3P) are X(4160) and X(4140). Their masses are close to the theoretical ones. The experimental branching ratio of X(4160), $$\Gamma (X(4160) \to D\bar D)/\Gamma (X(4160) \to D*\bar D*) < 0.09$$ is compatible with that of χ c0(3P), 0.07. However the broad decay width of X(4160) cannot be explained by the open charm two-body decay. To assign X(4140) as χ c0(3P) is also possible, due to the compatibility of the total decay width, the further measurement of decay modes of X(4140) are expected to justify the assignment.

We have investigated the effect of {"type":"entrez-nucleotide","attrs":{"text":"U73122","term_id":"4098075","term_text":"U73122"}}U73122, a specific inhibitor of phospholipase C (PLC), on acetylcholine-activated K+ currents (IKACh) in mouse atrial myocytes. In perforated patch clamp mode, IKACh was activated by 10 μM acetylcholine. When atrial myocytes were pretreated with {"type":"entrez-nucleotide","attrs":{"text":"U73122","term_id":"4098075","term_text":"U73122"}}U73122 or {"type":"entrez-nucleotide","attrs":{"text":"U73343","term_id":"1688125","term_text":"U73343"}}U73343, IKACh was inhibited dose-dependently (half-maximal inhibition at 0.12±0.0085 and 0.16±0.0176 μM, respectively). The current-voltage relationships for IKACh in the absence and in the presence of {"type":"entrez-nucleotide","attrs":{"text":"U73122","term_id":"4098075","term_text":"U73122"}}U73122 showed that the inhibition occurred uniformly from −120 to +40 mV, indicating a voltage-independent inhibition. When {"type":"entrez-nucleotide","attrs":{"text":"U73122","term_id":"4098075","term_text":"U73122"}}U73122 was applied after IKACh reached steady-state, a gradual decrease in IKACh was observed. The time course of the current decrease was well fitted to a single exponential, and the rate constant was proportional to the concentration of {"type":"entrez-nucleotide","attrs":{"text":"U73122","term_id":"4098075","term_text":"U73122"}}U73122. When KACh channels were directly activated by adding 1 mM GTPγS to the bath solution in inside-out patches, {"type":"entrez-nucleotide","attrs":{"text":"U73122","term_id":"4098075","term_text":"U73122"}}U73122 (1 μM) decreased the open probability significantly without change in mean open time. When KACh channels were activated independently of G-protein activation by 20 mM Na+, open probability was also inhibited by {"type":"entrez-nucleotide","attrs":{"text":"U73122","term_id":"4098075","term_text":"U73122"}}U73122. Voltage-activated K+ currents and inward rectifying K+ currents were not affected by {"type":"entrez-nucleotide","attrs":{"text":"U73122","term_id":"4098075","term_text":"U73122"}}U73122. These findings show that inhibition by {"type":"entrez-nucleotide","attrs":{"text":"U73122","term_id":"4098075","term_text":"U73122"}}U73122 and {"type":"entrez-nucleotide","attrs":{"text":"U73343","term_id":"1688125","term_text":"U73343"}}U73343 of KACh channels occurs at a level downstream of the action of Gβγ or Na+ on channel activation. The interference with phosphatidylinositol 4,5-bisphosphate (PIP2)-channel interaction can be suggested as a most plausible mechanism. Keywords: {"type":"entrez-nucleotide","attrs":{"text":"U73122","term_id":"4098075","term_text":"U73122"}}U73122, {"type":"entrez-nucleotide","attrs":{"text":"U73343","term_id":"1688125","term_text":"U73343"}}U73343, acetylcholine-activated K+ current, phospholipase C, phospholipase C inhibitor, atrial myocytes, phosphatidylinositol 4,5-bisphosphate, patch-clamp Introduction {"type":"entrez-nucleotide","attrs":{"text":"U73122","term_id":"4098075","term_text":"U73122"}}U73122 has been shown to inhibit phospholipase C (PLC) at low micromolar concentrations (Smith et al., 1990; Bleasdale et al., 1990), and it is one of the most widely used PLC inhibitors. Very often the structurally related {"type":"entrez-nucleotide","attrs":{"text":"U73343","term_id":"1688125","term_text":"U73343"}}U73343 is used as negative control, since it does not inhibit PLC (Smith et al., 1990; Bleasdale et al., 1990). Recent studies, however, indicate that the action of {"type":"entrez-nucleotide","attrs":{"text":"U73122","term_id":"4098075","term_text":"U73122"}}U73122 and {"type":"entrez-nucleotide","attrs":{"text":"U73343","term_id":"1688125","term_text":"U73343"}}U73343 may not be specific as originally thought, since both agents also inhibit phospholipase D activity (Bosch et al., 1998), and since {"type":"entrez-nucleotide","attrs":{"text":"U73122","term_id":"4098075","term_text":"U73122"}}U73122 elicits intracellular calcium release (Muto et al., 1997). Furthermore, the non-selective actions of {"type":"entrez-nucleotide","attrs":{"text":"U73122","term_id":"4098075","term_text":"U73122"}}U73122 were also shown for a variety of receptor-mediated signal transductions, such as adenosine A1-receptor (Walker et al., 1998) and histamine H1-receptor (Hughes et al., 2000). ACh-activated K+ currents (IKACh) are responsible for the inhibitory effect of cardiac function by ACh (Jan & Jan, 1997; Yamada et al., 1998). Activation of IKACh by ACh receptors (mAChR) is mediated via the pertussis toxin-sensitive G-protein. G-protein-ion channel coupling mechanisms have been widely investigated for IKACh and its molecular equivalent G-protein-gated inwardly rectifying K+ channels (GIRK), and it is now believed that the direct binding of G protein Gβγ subunits to the channel protein opens GIRK channels (Huang et al., 1995; Krapivinsky et al., 1995; Kunkel & Peralta, 1995; Inanobe et al., 1995). In addition to Gβγ subunits, GIRK channels can also be activated by Na+ ions through G-protein-independent pathway (Sui et al., 1996; 1998). Both Gβγ subunits and Na+ ion cause a stabilization of phosphatidylinositol 4,5-bisphosphate (PIP2)-channel interaction, which is absolutely required for channel opening (Huang et al., 1998). In the present study, we investigated the effects of {"type":"entrez-nucleotide","attrs":{"text":"U73122","term_id":"4098075","term_text":"U73122"}}U73122 and {"type":"entrez-nucleotide","attrs":{"text":"U73343","term_id":"1688125","term_text":"U73343"}}U73343 on IKACh in mouse atrial myocytes and found that both inhibit IKACh independently of PLC inhibition. The inhibition was almost complete at concentrations similar to or below those used for PLC inhibition. The target for {"type":"entrez-nucleotide","attrs":{"text":"U73122","term_id":"4098075","term_text":"U73122"}}U73122 action was investigated using inside-out patch recording, showing that the inhibition by {"type":"entrez-nucleotide","attrs":{"text":"U73122","term_id":"4098075","term_text":"U73122"}}U73122 occurs even when the channels are activated by Na+ independently of G-protein activation. These results suggest that {"type":"entrez-nucleotide","attrs":{"text":"U73122","term_id":"4098075","term_text":"U73122"}}U73122 inhibits KACh channels possibly by the interference with PIP2-channel interaction.

The angular distribution of the 42 MeV 7Li sequential breakup (via (7/2)-, 4.63 MeV state) with 58Ni target, measured beyond the grazing angle, is presented. Analyses of both elastic scattering and sequential breakup are carried out in a continuum-discretized coupled channel framework. In sequential breakup, contributions from multi-step processes are found to be significant at this low incident energy.