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Invasion and metastasis are the major characteristics of malignant tumors and are complex processes involving multiple genes. Gene regulation is a precise, large and complex biological control system, and its underlying mechanisms remain to be elucidated. Mesenchymal-specific genes are expressed primarily by mesenchymal cells, and the expression products of these genes are molecules with various structures and functions, including secreted proteins and extracellular matrix proteins. The periostin gene has been newly identified as a mesenchymal-specific gene and an extracellular-matrix secreted protein. Periostin is able to bind to various subtypes of integrin receptors on the surface of the cell membrane. This triggers relevant signal transduction pathways to alter the microenvironment of cancer cells in order to facilitate their survival, invasion, metastasis and angiogenesis as well as enhance the tolerance to hypoxia and chemicals. Therefore, periostin is associated with the grade of malignancy, level of invasion and prognosis of malignant tumors. The in-depth study of periostin may provide an effective marker for tumor diagnosis and prognosis, as well as a novel treatment target. [ABSTRACT FROM AUTHOR]

Based on the photocurrent model, we study terahertz (THz) emission from argon plasmas induced by incommensurate-frequency two- and three-color laser fields. In order to enhance the THz radiation at an arbitrary frequency efficiently, a genetic algorithm is applied to search for the optimum laser parameters. For the longer two-color field, our optimizations show that the THz tunability is mainly determined by two laser frequencies, which approximately meets the law Ω = 2ω1--ω2. However, for the shorter laser pulse, the tunability of the THz wave with lower frequency also depends on the relative phase. To control the tunable THz emission, we systematically investigated how to generate the stronger THz wave with the shorter spectrum width using the optimal synthesized waveform. We found that the THz intensity can be enhanced by about an order with threecolor field compared with the two-color cases. We also show that the tunable single ultrashort THz pulses can be obtained by using an optimized 50-fs two-color pulse. [ABSTRACT FROM AUTHOR]

In this paper, we study the OZI-allowed twobody strong decays of 3-heavy-light mesons. Experimentally the charmed D*3 (2760) and the charm-strange D*s3(2860) states with these quantum numbers have been discovered. For the bottomed B(5970) state, which was found by the CDF Collaboration recently, its quantum number has not been decided yet and we assume it is a 3-meson in this paper. The theoretical prediction for the strong decays of bottom-strange state B*s3 is also given. The relativistic wave functions of 3-heavy mesons are constructed and their numerical values are obtained by solving the corresponding Bethe-Salpeter equation with instantaneous approximation. The transition matrix is calculated by using the PCAC and low energy theorem, following which the decay widths are obtained. For D*3 (2760) and D*s3(2860), the total strong decay widths are 72.6 and 47.6 MeV, respectively. For B* 3 with M = 5978 MeV and B*s3 with M = 6178 MeV, their strong decay widths are 22.9 and 40.8 MeV, respectively. [ABSTRACT FROM AUTHOR]

The new mesons X(3940) and X(4160) have been found by Belle Collaboration in the processes e+e-→J/ψD(∗)D¯(∗)e+e-→J/ψD(∗)D¯(∗). Considering X(3940) and X(4160) as ηc(3S)ηc(3S) and ηc(4S)ηc(4S) states, the two-body open charm OZI-allowed strong decay of ηc(3S)ηc(3S) and ηc(4S)ηc(4S) are studied by the improved Bethe-Salpeter method combined with the 3P03P0 model. The strong decay width of ηc(3S)ηc(3S) is Γηc(3S)=(33.5+18.4-15.3)Γηc(3S)=(33.5-15.3+18.4) MeV, which is close to the result of X(3940); therefore, ηc(3S)ηc(3S) is a good candidate of X(3940). The strong decay width of ηc(4S)ηc(4S) is Γηc(4S)=(69.9+22.4-21.1)Γηc(4S)=(69.9-21.1+22.4) MeV, considering the errors of the results, it is close to the lower limit of X(4160). But the ratio of the decay width Γ(DD¯*)Γ(D*D¯*)Γ(DD*)Γ(D*D¯*) of ηc(4S)ηc(4S) is larger than the experimental data of X(4160). According to the above analysis, ηc(4S)ηc(4S) is not the candidate of X(4160), and more investigations of X(4160) is needed. [ABSTRACT FROM AUTHOR]

We study the weak decays of B(s) and Bc into D-wave heavy-light mesons, including J P = 2- (D(s)2, D'(s)2, B(s)2, B'(s)2) and 3- (D∗(s)3, B*(s)3) states. The weak decay hadronic matrix elements are obtained based on the instantaneous Bethe-Salpeter method. The branching ratios for the B decays are B[ B →D²eνe] = 1.1-0.3 +0.3 ×10-3, B[ B → D' 2eνe] = 4.1-0.8+0.9 × 10-4, and B[ B → D∗ 3e¯νe] = 1.0-0.2 +0.2 ×10-3, respectively. For the semi-electronic decays of Bs to Ds2, D's2, and D∗ s3, the corresponding branching ratios are 1.7-0.5 +0.5 ×10-3, 5.2-1.5+1.6×10-4, and 1.5-0.4 +0.4 ×10-3, respectively. The branching ratios of the semi-electronic decays of Bc to D-wave D mesons are in the order of 10-5. We also obtained the forward-backward asymmetry, angular spectra, and lepton momentum spectra. In particular the distribution of decay widths for the 2- states D2 and D'² varying along with mixing angle are presented. [ABSTRACT FROM AUTHOR]

Based on the photocurrent model, we perform a theoretical study on the optimization of terahertz (THz) wave emission from argon gas irradiated by the two- and three-colour laser fields. To obtain stronger THz radiation for the given conditions, a genetic algorithm method is applied to search for the optimum laser parameters. For the two-colour field, our optimizations reveal two types of optimal scheme, and each one dominates the THz generation in different regions of intensity ratio for a given total laser intensity. One scheme is the combination of a fundamental laser pulse and its second harmonic, while the other is the fundamental pulse with its fourth harmonic. For each scheme, the optimal intensity ratio and phase delay are obtained. For the three-colour case, our optimization shows that the excellent waveform for the strongest THz radiation is composed of a fundamental laser pulse, and its second, third harmonics, with appropriate intensity ratio and carrier-envelope phase. Such a 3-colour field can generate strong THz radiation comparable with a 10-colour sawtooth wave [Martínez et al., Phys. Rev. Lett. 114, 183901 (2015)]. The physical mechanisms for the enhancement of THz wave emission in gases are also discussed in detail. Our results give helpful guidance for intense THz generation with tabletop femtosecond laser device in experiment. [ABSTRACT FROM AUTHOR]

We study the semileptonic and nonleptonic decays of Bc meson to D-wave charmonia, namely, ηc2(11 D2), ψ2(13 D2), and ψ3(13 D3). In our calculations, the instantaneous Bethe–Salpeter method is applied to obtain the hadronic matrix elements. This method includes relativistic corrections which are important especially for the higher orbital excited states. For the semileptonic decay channels with electron as the final lepton, we get the branching ratios B[Bc → ηc2eν¯e] = 5.9−0.8 +1.0 × 10−4, B[Bc → ψ2eν¯e] = 1.5−0.2 +0.3 × 10−4, and B[Bc → ψ3eν¯e] = 3.5−0.6 +0.8 × 10−4. The transition form factors, forward–backward asymmetries, and lepton spectra in these processes are also presented. For the nonleptonic decay channels, those with ρ as the lighter meson have the largest branching ratios, B[Bc → ηc2ρ] = 8.1−1.0 +1.0 × 10−4, B[Bc → ψ2ρ] = 9.6−1.0 +1.0 × 10−5, and B[Bc→ψ3ρ] = 4.1−0.7 +0.8 × 10−4. [ABSTRACT FROM AUTHOR]

We investigate how the intensity and duration of an attosecond pulse generated from high-order harmonic generation are affected by the pressure and thickness of the gas jet by taking into account the macroscopic propagation of both fundamental and harmonic fields. Our simulations show that, limited by the propagation effects, especially the absorption of harmonics, the intensity of an attosecond pulse cannot be improved by just independently increasing the gas pressure or the medium length. On the other hand, due to good phase-matching conditions, the duration of a generated attosecond pulse can be improved by changing the gas pressure. [ABSTRACT FROM AUTHOR]

With the same constituents of quark and antiquark, the p-wave state has a higher mass than the corresponding s-wave state, but the relativistic corrections are much larger in the processes of which p-wave mesons are involved. Considering this, the relativistic Bethe—Salpeter method is applied to estimate the branching fractions of semileptonic decays B(s) → D*(sJ)lν (J = 0,2). Our predictions are Br[ → (2317)l−ν̄] = 0.50%, Br[ → (2573)l−ν̄] = 0.40%, Br[B− → (2400)l−ν̄] = 0.79%, Br[B− → (2460)l−ν̄] = 0.28%, Br[ → (2400)l−ν̄] = 0.58% and Br[ → (2460)l−ν̄] = 0.27%. . [ABSTRACT FROM AUTHOR]

The nonleptonic decays from B0 and B0 to an orbitally excited P-wave charmed meson are studied within the naive factorization hypothesis. Based on the Mandel-stam formalism, and under the framework of the improved Bethe-Salpeter method, the hadronic matrix elements of the decays B0s → D(*)+sJ X- and B0 → D(*)+J X- (X -- &03co, ρ, K, K*, D, D*, Ds, D*) are calculated, in which nonperturbative QCD effects are well considered by overlapping integral over the relativistic Salpeter wave functions of initial and final states. Some of these decays have sizable branching fractions and are expected to be detected in the current and near future experiments. [ABSTRACT FROM AUTHOR]

The recent BaBar results raise the possibility that X(3872) has negative parity; reassigning it to the 11D2(c...) state should therefore be considered. In this paper we give a general form of the wave function of 2-+ mesons. By solving the instantaneous Bethe-Salpeter equation, we get the mass spectrum and corresponding wave functions. We calculate the electromagnetic decay widths of the first 2-+ state which we assume to be the X(3872) particle. The results are Γ(2−+(3872) → J/ψγ) = 1.59+0.53−0.42 keV, Γ(2−+(3872) → ψ(2S)γ) = 2.87+1.46−0.97 eV and Γ(2−+(3872) → ψ(3770)γ) = 0.135+0.066−0.047 keV. The ratio of the branch fractions of the second and the first channels is about 0.002, which is inconsistent with the experimental value 3.4 ± 1.4. Therefore X(3872) is unlikely to be a 2-+ charmonium state. In addition, we obtain a relatively large decay width for the 2-+ (3872) → hcγ channel, 392+62-111 keV. [ABSTRACT FROM AUTHOR]

We study the production of first radial excited states Dq(2S) (q = u, d, s) and Bq(2S) in exclusive semi-leptonic Bq' (q' = u, d, s, c) decays by the improved Bethe-Salpeter method. These 2S states can be detected through their strong decays to ground mesons, where the strong decays are calculated by the low-energy approximation as well as the impulse approximation. Some channels have ratios of order 10-4: Br(B+ → &Dmacr;0(2S)ℓ+νℓ) × Br(&Dmacr;0(2S) → &Dmacr;*&pgr;) " (4.9 ± 4.0) × 10-4, Br(B0 → D-(2S)ℓ+νℓ) × Br(&Dmacr;0(2S) → &Dmacr;*π) " (4.4 ± 3.4) × 10-4. These channels could be measured by the current B-factories. For Ds(2S), we also obtain a relative large ratio: Br(B0s → D-s (2S)ℓ+νℓ) × Br(D-s(2S) → &Dmacr;* &Kmacr) " (9.9 ± 14.9) × 10-4. Although there are discrepancies in the full decay width between the theoretical predictions of D0(2S) and the experimental results of D(2550)0, the new detected state D(2550)0 is very likely the D0(2S) state. [ABSTRACT FROM AUTHOR]

The experimental observation of lepton-number violating processes would unambiguously indicate the Majorana nature of neutrinos. Various ΔL=2 processes for pseudoscalar meson M1 decays to another pseudoscalar meson M2 and two charged leptons l1, l2 ( M1+→l1+l2+M2-) have been studied extensively. Extending the existing literature on the studies of these kinds of process, we consider the rare decays of heavy mesons to a vector meson or a pseudoscalar meson. These processes have not been searched for experimentally, while they may have sizable decay rates. We calculate their branching fractions and propose to search for these decay modes in the current and forthcoming experiments, in particular at the LHCb. [ABSTRACT FROM AUTHOR]

CCAAT/Enhancer Binding Proteins family proteins are important regulators of liver functions. Here, we show the critical role of C/EBPα-mediated chromatin remodeling in the age-associated dysfunctions of the liver and in the maintenance of physiological homeostasis. Because ph-S193 isoform of C/EBPα is increased in livers of old mice, we have generated C/EBPα-S193D knockin mice, which mimic the ph-S193 isoform of C/EBPα. Analyses of these mice showed that the S193D mutation causes chromatin remodeling leading to histological appearance of ‘foci-like’ nodules, which are also observed in livers of old mice. These ‘foci-like’ structures contain K9 trimethylated histone H3, a marker of heterochromatin. The increase of heterochromatin regions in S193D mice correlates with the elevation of S193D-C/EBPα-HDAC1 complexes and with dys-regulation of gene expression including epigenetic silencing of cyclin D1 and D2 promoters and the inhibition of liver proliferation. The elimination of C/EBPα-HDAC1 complexes in S193D mice by inhibition of HDAC1 corrects chromatin structure and normalizes expression of cyclin D1 and D2. We found that epigenetic dys-regulation is also associated with the elevation of C/EBPβ and with the increase of C/EBPα/β heterodimers in S193D mice. The C/EBPα/β heterodimers activate transcription of Glut4 and increase the levels of Glut4. As the result, S193D livers have accelerated uptake of glucose and accumulation of glycogen in the liver. Thus, this study demonstrates that the phosphorylation of C/EBPα at S193 leads to the appearance of heterochromatin regions, which correlates with the development of age-related dysfunctions of the liver. [ABSTRACT FROM AUTHOR]

The purpose of this study was to investigate the role of the mutant CUGn RNA in the induction of stress in type 1 myotonic dystrophy (DM1) cells and in the stress-mediated inhibition of protein translation in DM1. To achieve our goals, we performed HPLC-based purification of stress granules (SGs), immunoanalysis of SGs with stress markers TIA-1, CUGBP1, and ph-eIF2, site-specific mutagenesis, and examinations of RNA-protein and protein-protein interactions in myoblasts from control and DM1 patients. The cause-and-effect relationships were addressed in stable cells expressing mutant CUG repeats. We found that the mutant CUGn RNA induces formation of SGs through the increase of the double-stranded RNA-dependent protein kinase (PKR) and following inactivation of eIF2α, one of the substrates of PKR. We show that SGs trap mRNA coding for the DNA repair and remodeling factor MRG15 (MORF4L1), translation of which is regulated by CUGBP1. As the result of the trapping, the levels of MRG15 are reduced in DM1 cells and in CUG-expressing cells. These data show that CUG repeats cause stress in DM1 through the PKR-ph-eIF2α pathway inhibiting translation of certain mRNAs, such as MRG15 mRNA. The repression of protein translation by stress might contribute to the progressive muscle loss in DM1. [ABSTRACT FROM AUTHOR]

The diquark structure in baryons is commonly accepted as a reasonable approximation which can much simplify the picture of baryons and reduce the length of calculations. However, a diquark by no means is a point-like particle, even though it is treated as a whole object. Therefore, to apply the diquark picture to phenomenological calculations, at the effective vertices for the diquark–gauge-boson interactions, suitable form factors must be introduced to compensate the effects caused by the inner structure of the diquark. It is crucial to derive the appropriate form factors for various interactions. In this work, we use the Bethe–Salpeter equation to derive such form factors and numerically evaluate their magnitudes. Our results not only qualitatively, but also quantitatively confirm the form factors phenomenologically introduced in literature. [ABSTRACT FROM AUTHOR]

By analyzing the present situation of reservoir flood control operation, this paper proposes multi-person multiobjective decision-making model for the problems of flood control operation. The model takes the influence of multiobjectives and experience and knowledge of decision-makers into account. In order to find an optimal alternative decided by multiple decision-makers from all the given alternatives, the relative optimal membership degree of every decision-maker to every alternative is first obtained and then the optimal membership degree of every decision-maker to every alternative is obtained which collects group preferences through two stages. The advantages of this model are simple and more adaptable to the practical problem. The model is demonstrated by application in Fengman Reservoir located in Songhua River Basin in China. Of course, this method can also be applied in other science fields. [ABSTRACT FROM AUTHOR]

Induction of p21 in senescent human fibroblasts plays a key role in the inactivation of cyclin-dependent kinases and the resulting irreversible growth arrest in the early stages of cell senescence. We found that RNA-binding proteins are critical regulators of p21 during senescence. Two RNA-binding proteins, CUGBP1 and calreticulin (CRT), interact with the same nucleotide sequences within the 5' region of p21 mRNA, but have opposite effects on the translation of p21 mRNA. CUGBP1 increases translation of p21 mRNA, whereas CRT blocks translation of p21 via stabilization of a stem-loop structure within the 5' region of the p21 mRNA. CUGBP1 and CRT compete for binding to p21 mRNA and thereby the regulation of p21 translation. In senescent fibroblasts, CUGBP1 displaces CRT from the p21 mRNA and releases CRT-dependent repression of p21 translation leading to growth arrest and development of a senescent phenotype. These data present evidence that competition between RNA-binding proteins for the regulation of p21 translation determines cell fate. [ABSTRACT FROM AUTHOR]

The low-order harmonic generation of hydrogen molecular ion interacting with a linearly polarized laser field has been investigated theoretically by using a simple two-state model. The validity of the two-state model is carefully examined by comparing the harmonic spectra of hydrogen molecular ion obtained from this model with those from the three-dimensional time-dependent Schrödinger equation. When combined with the Morlet transform of quantum time-frequency spectrum, the two-state model can be used to study the dynamical origin of the low-order harmonic generation of hydrogen molecular ion driven by low-frequency pulses. In addition, some interesting structures of the time profiles for low order harmonics are obtained. [ABSTRACT FROM AUTHOR]

In this paper we study the semileptonic decays of B*, , and by using the Bethe–Salpeter method with instantaneous approximation. Both the and cases are considered. The largest partial width of these channels is of the order of 10−14 GeV. The branching ratios of these semileptonic decays are also estimated by using the partial width of the one photon decay channel to approximate the total width. For and , the branching ratios are of the order of 10−8 and 10−7, respectively. For , the and channels have the largest branching ratio, which is of the order of 10−6. [ABSTRACT FROM AUTHOR]

Above-threshold ionization (ATI) of a hydrogen atom exposed to chirped laser fields is investigated theoretically by solving the time-dependent Schrödinger equation. By comparing the energy spectra, the two-dimensional momentum spectra, and the angular distributions of photoelectron for the laser pulses with different chirp rates, we show a very clear chirp dependence both in the multiphoton and tunneling ionization processes but no chirp dependence in the single-photon ionization. We find that the chirp dependence in the multiphoton ionization based ATI can be attributed to the excited bound states. In the single-photon and tunneling ionization regimes, the electron can be removed directly from the ground state and thus the excited states may not be very important. It indicates that the chirp dependence in the tunneling ionization based ATI processes is mainly due to the laser pulses with different chirp rates. [ABSTRACT FROM AUTHOR]

We investigate high-order harmonic generation (HHG) of Li+ ion driven by an intense infrared (IR) laser field in combination with a weak XUV pulse. To achieve this, we first construct an accurate single-active electron angular-momentum-dependent model potential of Li+ ion, by which the accurate singlet energy levels of Li+ for the ground state and excited states with higher quantum numbers can be obtained. Then, we solve numerically the three dimensional time-dependent Schrödinger equation of Li+ ion by means of the generalized pseudospectral method to obtain HHG. Our results show that the strength of assisted XUV is not amplified during the harmonic generation process, but the yield of HHG power spectrum in the whole plateau has a significant enhancement. Furthermore, the optimal phase delay between the IR and XUV pulses allows the production of ultrabroadband supercontinuum spectra. By superposing some harmonics, a strong new single 27-attosecond ultrashort pulse can be obtained. [ABSTRACT FROM AUTHOR]

The existence of heavy meson lepton number violating (LNV) processes shows the Majorana nature of the neutrino. Much of this theoretical and experimental researche focuses on this type of decay. Four-body epton-number violation (LNV) processes of the B meson may have sizable branching ratios as they share the same vertex and mixing parameters with the three-body case. Mixing parameters between the heavy Majorana neutrino and charged leptons extracted from the three-body case can be used to constrain the branching ratios of four-body decays of the B meson. So we can update the upper limits of these mixing parameters with new experimental data of the three-body LNV decays. We also analyze using the updated parameters and estimate some channels’ reconstruction events using current experimental data from Belle. [ABSTRACT FROM AUTHOR]

We investigate theoretically the ionization properties of the valence electron for the alkali metal atom Na in an intense pulsed laser field by solving numerically the time-dependent Schrödinger equation with an accurate l-dependent model potential. By calculating the variations of the ionization probabilities with laser peak intensity for wavelengths ranging from 200 nm to 600 nm, our results present a dynamic stabilization trend for the Na atom initially in its ground state (3s) and the excited states (3p and 4s) exposed to an intense pulsed laser field. Especially a clear “window” of dynamic stabilization at lower laser intensities and longer wavelengths for the initial state 4s (the second excited state) is found. By analyzing the time-dependent population distributions of the valence electron in the bound states with the different values of principal quantum number n and orbital quantum number l, we can attribute the dynamic stabilization to the periodic population in the low-excited states since the valence electron oscillates rapidly between the lowly excited states and the continuum states. [ABSTRACT FROM AUTHOR]

This paper discusses four-body lepton number violating tau decay. We study the processes and to determine the nature of the neutrino. The first process violates the lepton number by two units, which can only happen through an internal Majorana. The second one conserves the lepton number but violates the lepton flavor, which can take place with both a Majorana neutrino and a Dirac neutrino. We calculate their branching ratio (BR) and differential BR to distinguish between the Majorana neutrino and the Dirac neutrino. We also propose an experiment to perform this detection. [ABSTRACT FROM AUTHOR]

The above-threshold detachment ofions induced by a linearly polarized few-cycle laser pulse is investigated theoretically using the strong-field approximation model without considering the rescattering mechanism. We first derive an analytical form of transition amplitude for describing the strong-field photodetachment ofions. The integration over time in transition amplitude can be performed using the numerical integration method or the saddle-point (SP) method of Shearer et al. [Phys. Rev. A 88 (2013) 033415]. The validity of the SP method is carefully examined by comparing the energy spectra and photoelectron angular distributions (PADs) with those obtained from the numerical integration method. By considering the volume effect of a focused laser beam, both the energy spectra and the low-energy PADs calculated by the numerical integration method agree very well with the experimental results. [ABSTRACT FROM AUTHOR]

In this paper we study the weak decays of and . The cases when the final mesons are pseudo-scalars or vectors are considered. Using the Bethe–Salpeter method, we calculate the hadronic transition amplitude and give the form factors. The energy spectra of leptons for the semi-leptonic channels are also presented for convenience. In the calculation of non-leptonic decays, the naive factorization is applied. And all types of such channels, namely, flavor-favored or suppressed and color-favored or suppressed, are calculated. Our results show that, for the semi-leptonic decay modes, the largest branching ratios are of the order of 10−10 both for and decays, and the largest branching ratios of non-leptonic decays are of the order of 10−9 for and 10−10 for . [ABSTRACT FROM AUTHOR]

Considering X(3940) and X(4160) as and , we study the production of X(3940) and X(4160) in exclusive weak decays of the Bc meson by the improved Bethe–Salpeter (BS) method. Using the relativistic BS equation and the Mandelstam formalism, we calculate the corresponding decay form factors. The predictions of the corresponding branching ratios are: and . This will provide a new way to observe X(3940) and X(4160) in the future, as well as to improve the knowledge of Bc meson decay. [ABSTRACT FROM AUTHOR]

We investigate the plasmonic-field-enhanced high-order harmonic generation (HHG) of H atom driven by few-cycle laser pulses, by solving the time-dependent Schrödinger equation (TDSE). Compared with the homogeneous field, HHG spectra generated by inhomogeneous field exhibit two-plateau structure. We analyze the origin of the two plateaus by using the semiclassical trajectory method. Our results from both classical and TDSE simulations show that the cutoffs of the two plateaus are dramatically affected by the carrier-envelope phase (CEP) of laser pulse in the inhomogeneous field, even for a little longer pulse. Thus, we can determine the CEP of driving laser based on the cutoff position of HHG generated in the inhomogeneous field. [ABSTRACT FROM AUTHOR]

In this paper, we study the rare radiative processes within the Standard Model, where stands for the meson , or . During the investigations, we consider the contributions from the penguin, annihilation, color-suppressed and color-favored cascade diagrams. Our results show that: (1) the penguin and annihilation contributions are dominant in the branching fractions; (2) for the processes and , the effects from the color-suppressed and color-favored cascade diagrams are un-negligible. [ABSTRACT FROM AUTHOR]

We extend the adiabatic saddle-point (SP) method of Shearer et al (2011 Phys. Rev. A 84 033409) to study electron detachment from H− exposed to a two-color few-cycle linearly polarized laser pulse that consists of a fundamental frequency and its half harmonic. We show that the photoelectron angular distributions (PADs) are dominantly contributed from several central SPs that correspond to the strongest part of two-color pulses. By separately calculating the PADs formed in the different detachment steps, the rich oscillatory patterns in the PADs can be mainly attributed to the interference effects of coherent quantum wave packets in the classical propagation step of detachment processes, whereas the interference effects in the quantum tunneling step are weaker because the corresponding shape of the PADs is almost independent of the relative time delay of two pulses. The interference effects in the classical propagation step are also confirmed by the angle-dependent averaged cosine value of phase differences for each two dominant SPs. We find that the PADs of H− ions can be efficiently controlled by properly adjusting the relative time delay and intensity ratio of a controlling field to the driving field. [ABSTRACT FROM AUTHOR]

The interference of high-order harmonics generated by two successive gas jets within a single laser pulse is discussed by a modeling with the inclusion of macroscopic propagation of the fundamental and harmonic fields in an ionizing medium. Based on the interference, we show that one can extract the laser Rayleigh range from the interference of harmonics and the accuracy of retrieve is independent of carrier-envelope phase while dependent on the pulse duration. Moreover, we demonstrate that it is possible to optimize the single or range of harmonics with a high ratio relative to the adjacent orders by changing the separation of two gas jets, which is unavailable by using a single gas jet and linear polarized laser pulse. [ABSTRACT FROM AUTHOR]

Aging reduces the regenerative capacities of many tissues. In this paper, we show a critical role of the glycogen synthase kinase 3β (GSK3β)-cyclin D3 pathway in the loss of the regenerative capacity of the liver. In young animals, high levels of growth hormone (GH) increase expression of GSK3β, which associates with cyclin D3 and triggers degradation of cyclin D3. In livers of old mice, the GSK3β promoter is repressed by C/EBPβ-histone deacetylase 1 (HDAC1) complexes, leading to the reduction of GSK3β. The treatment of old mice with GH increases expression of GSK3β via removal of the C/EBPβ-HDAC1 complexes from the GSK3β promoter. We found that the GSK3β-cyclin D3 pathway is also altered in young GH-deficient Little mice and that treatment of Little mice with GH corrects the GSK3β-cyclin D3 pathway. We present evidence that GSK3β regulates liver proliferation by controlling growth-inhibitory activity of C/EBP. The downregulation of GSK3β in young mice inhibits liver proliferation after partial hepatectomy via the cyclin D3-C/EBP pathway, while the elevation of GSK3β in old mice accelerates liver proliferation. Thus, this paper shows that GSK3β is a critical regulator of liver proliferation and that the reduction of GSK3β with age causes the loss of regenerative capacities of the liver. [ABSTRACT FROM AUTHOR]

Close-coupling calculations based on an R-matrix formalism are performed for the 1s–2p resonance photoionizations from the low-lying states of boron-like carbon ions. The resonance energies, widths and oscillator strengths of 1s–2p core excitations are determined by analysing the calculated photoionization cross sections. Our calculations are in reasonable agreement with the experimental and theoretical results presented by other authors. The present numerical values may help to analyse the astrophysical and laboratory plasmas. [ABSTRACT FROM AUTHOR]

C/EBPα arrests proliferation of young livers by inhibition of cdk2. In old mice, C/EBPα inhibits growth by repression of E2F-dependent promoters through the C/EBP-αBrm complex. In this paper, we show that cyclin D3-cdk4/cdk6 supports the ability of C/EBPα to inhibit liver proliferation in both age groups. Although cyclin D3-cdk4/cdk6 kinases are involved in the promotion of growth, they are expressed in terminally differentiated cells, suggesting that they have additional functions in these settings. We demonstrate that C/EBPα represents a target for phosphorylation by cyclin D3-cdk4/cdk6 complexes in differentiated liver cells and in differentiated adipocytes. Cyclin D3-cdk4/cdk6 specifically phosphorylate C/EBPα at Ser193 in vitro and in the liver and support growth-inhibitory C/EBP-cdk2 and C/EBP-Brmα complexes. We found that cyclin D3 is increased in old livers and activates cdk4/cdk6, resulting in stabilization of the C/EBPα-Brm complex. Old livers fail to reduce the activity of cyclin D3-cdk4/cdk6 after partial hepatectomy, leading to high levels of C/EBPα-Brm complexes after partial hepatectomy, which correlate with weak proliferation. We examined the role of cyclin D3 in the stabilization of C/EBPα-cdk2 and C/EBPα-Brm by using 3T3-L1 differentiated cells. In these cells, cyclin D3 is increased during differentiation and phosphorylates C/EBPα at Ser193, leading to the formation of growth-inhibitory C/EBPα-cdk2 and C/EBPα-Brm complexes. The inhibition of cyclin D3 blocks the formation of these complexes. Thus, these studies provide a new function of cyclin D3, which is to support the growth-inhibitory activity of C/EBPα. [ABSTRACT FROM AUTHOR]