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Shoot-tip abortion is a very common phenomenon in some perennial woody plants and it affects the height, architecture, and branch orientation of trees; however, little is currently known about the underlying mechanisms. In this study, we identified a gene in sweet orange (Citrus sinensis) encoding a KNAT-like protein (CsKN1) and found high expression in the shoot apical meristem (SAM). Overexpression of CsKN1 in transgenic plants prolonged the vegetative growth of SAMs, whilst silencing resulted in either the loss or inhibition of SAMs. Yeast two-hybrid analysis revealed that CsKN1 interacted with another citrus KNAT-like protein (CsKN2), and overexpression of CsKN2 in lemon and tobacco caused an extreme multiple-meristem phenotype. Overexpression of CsKN1 and CsKN2 in transgenic plants resulted in the differential expression of numerous genes related to hormone biosynthesis and signaling. Yeast one-hybrid analysis revealed that the CsKN1-CsKN2 complex can bind to the promoter of citrus floral meristem gene LEAFY (CsLFY) and inhibit its expression. These results indicated that CsKN1 might prolong the vegetative growth period of SAMs by delaying flowering. In addition, an ethylene-responsive factor (CsERF) was found to bind to the CsKN1 promoter and suppresses its transcription. Overexpression of CsERF in Arabidopsis increased the contents of ethylene and reactive oxygen species, which might induce the occurrence of shoot-tip abscission. On the basis of our results, we conclude that CsKN1 and CsKN2 might work cooperatively to regulate the shoot-tip abscission process in spring shoots of sweet orange.

Leaf shape is an important agronomic trait that is involved in plant photosynthesis, flowering, disease resistance, and yield. In recent years, many leaf shape-related genes have been identified in model plants, but the precise regulatory network of leaf shape development remains unclear, particularly in woody plants. Transcriptome analysis of trifoliate orange and lemon leaves revealed that two citrus Knotted1-like (CiKN1 and CiKN6) genes might participate in leaf development. Overexpression of CiKN1 displays lobed leaves in simple leaf Arabidopsis and lemon. Further protein interaction analysis revealed that CiKN6 interacted with CiKN1, whose overexpression resulted in deeper lobed leaves in transgenic Arabidopsis and lemon. Suppressing CiKN6 expression also affected the development of lemon leaves. Furthermore, we found that the CiKN1-CiKN6 complex specifically binds to the citrus miR164a promoter and suppresses its expression. In addition, a SQUAMOSA promoter binding protein-like (SPL) gene (CiSPL11) was identified using yeast one-hybrid assays and was found to promote CiKN6 transcription by binding to its promoter. Transgenic Arabidopsis showed that CiSPL11 might be involved in the development of citrus leaves. These results suggested that the CiKN1-CiKN6 complex and miR164a interact to regulate leaf development in citrus.

BACKGROUND Acute liver injury in the setting of hepatic fibrosis is an intriguing and still unsettled issue. We previously have demonstrated the protective effects conferred by M2-like macrophages in the fibrotic liver. In the present work, we further decipher the cellular mechanisms governing this hepatoprotection. MATERIAL AND METHODS Macrophages were isolated from control mice (M0 macrophages), then polarized into M1 or M2 phenotype using IFN-γ or IL-4, respectively. Conditioned media (CM) from M0, M1, and M2 macrophages were harvested and applied to M1 macrophages. Cell apoptosis was evaluated by immunostaining and real-time PCR. Similarly, human monocyte-derived macrophages were isolated and polarized, then M0, M1, and M2 CM were applied to HL-7702 or HepG2 cells followed by apoptosis induction. Cell apoptosis was assessed by flow cytometry. RESULTS For the mouse conditioned medium experiment, stronger expression of cleaved caspase 3 and higher Bax/Bcl-2 mRNA ratio were found in M1 macrophages pretreated with M2 CM compared to those in M1 macrophages pretreated with M0 or M1 CM. Similarly, exposure of HL-7702 and HepG2 cells to either M0 or M1 CM had no significant effect on cell apoptosis. Nevertheless, the frequency of hepatocyte apoptosis was substantially reduced in HL-7702 (from 32.23±2.99 to 15.37±0.69 for Annexin V+/PI+ staining, p

Objective To investigate the effects of plasma from patients with acute on chronic liver failure on the proliferation and biotransformation function of C3A cells in vitro, and provide experimental data for C3A cells to be efficiently used in the bioartificial liver system. Methods C3A cells were incubated in 100% normal human plasma (NHP) and 100% abnormal plasma (AP) from patients with acute on chronic liver failure. Growth morphology of the two groups were observed under inverted microscope and scanning electron microscope. The method of methyl thiazolyl tetrazolium (MTT) was conducted for the proliferation activities of C3A cells. The cellular apoptosis rates were assessed by the flow cytometer. The biotransformation function of cells was evaluated through diazepam metabolic amount assay. The concentrations of epithelial growth factor (EGF), transforming growth factor-α (TGF-α) and interleukin-1 (IL-1) were detected in plasma of the two groups. Results A: The proliferation activities of C3A cells incubated in 100% AP for 24, 48, 72, 96 and 120 hours were significantly higher than that in 100% NHP (P < 0.01). B: Observation under the inverted microscope indicated that the cells in 100% AP were growing faster than those in 100% NHP after cells attached to the plastic at 24 and 48 hours. The same phenomena was observed under the scanning electronic microscope. C: The C3A cells cultured in both groups of plasma showed the same apoptosis rate at 48 hours and there was no statistical difference. D: The diazepam metabolic value of C3A cells incubated in 100% AP for 24, 72 and 120 hours were lower than that in 100% NHP and were statistically different (P < 0.01). E: The concentrations of TGF-α, EGF and IL-1 in AP were significantly higher than that in NHP (P < 0.01). Conclusions Compared with normal human plasma, the plasma from patients with acute on chronic liver failure has more obvious effect to facilitate the proliferation of C3A cells, but also decreases partial biotransformation function of C3A cells.

A compact set of equations based on the multiple subbands quasi-ballistic transport theory is developed, and is used to investigate the channel electron effective mobility in recently reported In0.53Ga0.47As/Al2O3 tri-gate n-FinFET. The extracted electron effective mobility mu(n) is around 370 cm(2)/V.s at low V-g-V-th bias at room temperature and decreases with increasing V-g, and increases with increasing temperature (240-332K). It is very different from the case of Si n-MOSFETs, where the electron mobility decreases with increasing temperature. The low channel effective mobility and the ab-normal temperature dependence of mu(n) are ascribed to the high acceptor interface trap and border trap energy densities in the conduction band energy of InGaAs. The ballistic channel resistance R-Ball at low V-ds is calculated and compared with the measured channel resistance R-CH. The low transmission coefficient T = R-Ball/R-CH approximate to 0.06 to 0.05 indicates that there is a large room to improve the InGaAs/Al2O3 n-FinFET performance.

The reliability performance of InxGa1-xAs n-type metal-oxide-semiconductor field-effect transistors with Al2O3 gate dielectric under positive-bias temperature instability stress is investigated systematically. A model of stress-induced border traps was proposed to interpret all charge pumping and I-V experimental results excellently. The stress-induced border traps include recoverable donor traps and permanent acceptor traps with respective energy densities Delta D-SOX(Donor) (E) and Delta D-SOX(Acceptor) (E). The shapes of Delta D-SOX(Donor) (E) and Delta D-SOX(Acceptor) (E) have been extracted from experimental data Delta D-SOX(Acceptor) (E) mainly distributes in the conduction band of InGaAs with a tail extending to the mid-gap, whereas Delta D-SOX(Donor) (E) has a large distribution inside the energy gap and extends to the conduction band. The high density of Delta D-SOX(Donor) (E) in the energy gap induces large degradation in the OFF-current, which is particularly serious when the In composition x is raised to 0.65.

To assess the efficacy of transcutaneous electrical acupoint stimulation (TEAS) in preventing the relapse of detoxified heroin users in a period of 12 months.A total of 164 rehabilitating heroin users in Shanghai area were recruited after compulsory detoxification treatment for a period ranging from 3 months to 3 years. The TEAS was executed by the device named Han's acupoint nerve stimulator (HANS). The patients were treated with HANS for at least 3 months. All the subjects were then followed up for one year and relapse was monitored by monthly heroin/morphine urinalysis.Of 164 rehabilitating former heroin addicts, 53 remained drug-free at the end of 12 months observation period as judged by negative urinalysis while 35 become relapsed as documented by positive urine tests. The rest 76 dropped off due to various reasons and were all counted into the category of "relapsed". Thus, our data indicated 32.3% rehabilitating heroin users could stay sober for at least one year, which is significantly higher than the existing reports that less than 5% detoxified abusers would stay drug free for one year with no further intervention. No obvious correlation was found between the susceptibility of relapse and the duration of compulsory detoxification.Compared to the existing literatures, our results indicate that HANS could produce a marked decrease of the relapse rate of rehabilitating heroin users after compulsory detoxification.

Monitoring the effectiveness of management activities within reserves is always a complicated task. When the focus of management activities is mammals, it is difficult to monitor their populations in a way that is rapid, effective, and inexpensive. We report on a mammal survey of a reserve in southwest China using remote-trip cameras. We surveyed 329 locations over 2 field seasons in 2002 and 2003. Sixteen species of mammals were detected with these cameras, with four species documented for the first time. After accounting for variation due to slope, aspect, elevation, and habitat type, the distribution of six species was positively associated with the location of conservation stations and/or patrolling routes. Species of medium-sized mammals are excellent candidates for monitoring programs based on these cameras, due to their relative abundance, sufficient size to be detected by the camera units, and sensitivity to human activity. The distribution of mammals relative to management efforts is a relatively rapid means to assess reserve effectiveness. The repeat use of the cameras as part of a monitoring plan should provide a quantifiable measure of reserve effectiveness.

The energy levels of the ideal divacancy states in band gap for more than 10 cubic semiconductors are invesgated by using the basic equations given in ref. [1] and the tight binding Hamiltonian given by vogl et al. A simple physical model is used to describe the basic physics of the divacancy problem.

By using Koster-Slater Green's function method and on-site defect potential approximation, a systematic method of A1 symmetric deep level wavefunction calculation of substitutional defect pairs is worked out. The method is applied to the spectator-oxygen pairs in GaP successfully. The Zn-O and Cd-O pair wavefunctions are obtained for the first time. The wavefunction is mainly concentrated on four bonds which locate at four nearest neighbour sites of oxygen center and point toward the oxygen. Nevertheless, the four bonds are not in the equal weight. The component of the bond which links spectator with oxygen is reduced in comparison with other three and it is more reduced for more electropositive spectator. The rest part of the wavefunction extends diversely over a wide range of space.

A complete set of equations for determining the energy levels and the wavefunc-tions with different symmetry of electronic states of the ideal divacancy in cubic semiconductors is obtained using the Koster-Slater Green's function method. Using an empirical tight binding Hamiltonian for the band structure of the host and the on-site pertubation approximation for the defect, only the on-site and the off-site Green's functions of the host and their derivatives with respect to energy E are involved in these equations.

A systematic investigation and numerical results of calculation of T2 symmetric deep level wave function induced by short range defect potential in Si are described, based on a recently developement on site defect potential Green's function method. [5,6] Such a complete information of T2 symmetric wave functions in Si is presented for the first time. The occupation probability P1 of the wave function located around four nearest neighbour sites of the defect center has a peak exceeding 50%. This part of wave function could be described by T2 symmetric combination of four hybrid orbital quasi dangling bonds located at four nearest neighbour sites and pointing toward the defect center. The total occupation probability of wave function located on the 0,1,2 shells arround the defect center is about 70%. The rest part of the wave function extends diversely over a wide range of space. The characteristics of the wave function are insensitive to the defect energy over most part of the energy range in the gap. Only when the defect energy level approaches very closely to the band edge of either conduction (Ec) or valence (Ev) band, the aforementioned peak P1 disappears and the wave function extends smoothly all over the space. A T2 symmetric deep level due to ideal vacancy is found at 0.51 eV up to the Ev.

New criterion for symmetric properties of defect potential in semiconductors is presented. For a degenerate energy level Es, we introduce the average Es of energy splitling under stress. Es is invariant under symmetry operation of Hamiltonian. Therefore, it is straight foward to reduce the stress coefficient tensor of Es by group theoretical method. For instance, for cubic semiconductors, if the defect level ET is withdefect potential of T group symmetry, the uniaxial stress coefficient of (?(Ec-ET))/(?F) or (?(ET-Ev))/(?F) is isotropic and equal to one third of corresponding hydrostatic pressurecoefficient. The case of defect potential with C3v symmetry is also discussed.The electron (or hole) emission and capture processes of defect levels under energy splitting are analysed. The weighted average of emission rate en and capture rate cn satisfy the following relation: en=gTgc-1cnN′ce(-(Bc-BT)/kT) By measuring the stress dependence of en., various schemes for determining the symmetry property of defect potential are discussed. The transient processes under defect level splitting are also discussed. When transitions are al lowed between the splitting states, the transient is exporential with single decay time constant en-1. When transitions between different states are forbidden, the transient is decay with multi-exponential time constants. en is determined by the initial transient slope.

The behavior of deep level wavefunctions induced by short range defect potential is investigated when the energy difference e between the defect state and the band edge is very small. When e→0, the wavefunctions tend to expand in real space and concentrate in k space when some symmetric matching condition is satisfied. A specific scheme is developed for efficient and reliable numerical calculations of the deep level wavefunctions when e is very small. For the case of A1 symmetric defect states near the bottom of the conduction band, for Si, when e 2 meV, the wavefunctions tend to concentrate rapidly in k space; for GaAs, the wavefunctio'ns do not concentrate in k space until e is as small as 0.1 meV. The critical e value corresponding to obvious concentration in k space is sensitive to the magnitude of the effective mass and the degree of matching of symmetry between the defect state and Bloch states at the band edge. For A1 defect states near the top of the valance band, no concentration in k space occur since the A1 defect states mismatch to the Block states at valance band maxima.

A simple method in the framework of Koster-Slater Green's function calculation and central cell defect potential (CGDP) approximation is used to calculate the distribution of deep level wavefunctions in Bloch space for Si, GaAs and GaP for the first time. Convergence properties are discussed. It is shown that for definite number of energy bands in the host crystal model, the convergence of deep level wavefunction calculations is faster than that of deep energy calculations.

The wavefunctions of the Eu, state and the Eg state are evaluated for the ideal divacancy in Si, using the basic equations given in [1] and the tight binding Hamiltonian given by P. Vogl et al. Comparison between the culculated results and the ESR and ENDOR spectra of V2+ and V2- in Si is discussed.

The hydrostatic pressure coefficient of gold acceptor levels Er in Silicon was measured by transient capacitance method. Under the pressure range of 0-8 Kbar, thepressure coefficient (?(Ec-ET))/(?P) =-1.9 meV/kbar. The electron capture cross section of gold acceptor centers does not depend on pressure within the experimental accuracy. By comparing the present result of hydrostatic pressure coefficient with the uniaxial pressure coefficient reported in [13], we conclude that the defect potential is lack of Td symmetry. Therefore, the gold acceptor levels are not originated by simple gold substitutional or interstitial configuration in Si crystals.

The wavefunctions of the A1 and E states of the ideal divacancy in GaAs, GaP are calculated using the basic equations given in ref. [1] and the tight-binding Hamiltonian given by P. Vogl et al. It is shown that the largest part of the wavefunctions of divacancy states is on the three nearest Ga atoms of the As or P vacancy, the rest part of the wavefunction decreases slowly and non-monotonically as the distance from the defect increases.