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Dendritic spines are small, ratchet-like protrusions on neuronal dendrites that form synapses for receiving neuronal messages. Dendritic spine morphology is associated with synapse function. If neurons degrade or are damaged, the spine morphology of neurons changes. Given that most commercially available spine analysis software is expensive and complex, this study investigated a semi-automated spine analysis software, CTSpine, and used previously published data to verify the accuracy of the analysis results of this software. We also applied CTSpine to understand whether aging causes alterations in the hippocampal spine morphology and whether physical exercise can impede dendritic spine changes in 20 male Sprague Dawley rats. The spines of pyramidal cells in the hippocampal Cornu Ammonis 1 (CA1) region in the aging group were more enriched in filopodium type pattern than those in the control group, whereas the spines of the exercised aging group showed a similar pattern to that of the control. No significant changes were observed in neuronal dendritic spines in other hippocampal regions. However, long-term hippocampal memory was considerably decreased in the aging group, which was reversed to some extent in the exercised aging group. CTSpine, a self-developed semi-automatic spine analysis software, showed results similar to those noted in published data and can be effectively applied to the study of dendritic patterns, including neurodevelopment and disease.

The immune synapse, a specialized interface formed between T lymphocytes and antigen-presenting cells (APCs) after antigen recognition, is essential for T cell activation and the adaptive immune response. It has been shown that this interface shares similarities with the primary cilium, a sensory organelle in eukaryotic cells, although roles of ciliary proteins on the immune synapse remain elusive. In this study, we find that inositol polyphosphate-5-phosphatase E (INPP5E), a cilium-enriched protein responsible for regulating phosphoinositide localization, accumulated at the immune synapse during antigen-specific conjugation or antibody capping, and formed a complex with CD3ζ, ZAP-70, and Lck. Silencing INPP5E in T-cells impaired polarized distribution of CD3ζ at the immune synapse, and correlated with a failure of PI(4,5)P2 clearance at the center of the synapse. Moreover, INPP5E silencing decreased proximal TCR signaling, including phosphorylation of CD3ζ and ZAP-70, and finally, attenuated IL-2 secretion. Our results suggest that INPP5E is a new player in phosphoinositide manipulation at the synapse, controlling the TCR signaling cascade.

Fine particulate matter 2.5 (PM2.5) induces free radicals and oxidative stress in animals, leading to a range of illnesses. In this study, Ganoderma Microsporum immunomodulatory (GMI) proteins were administered to alleviate PM2.5-induced inflammatory responses in mother rats, and PM2.5-induced inflammatory responses and neurological damage in their offspring. The results suggested that GMI administration decreased the risk of neurological disorders in mother rats and their offspring by reducing the white blood cell count, lessening inflammatory responses and PM2.5-induced memory impairment, and preventing dendritic branches in the hippocampi from declining and microRNAs from PM2.5-induced modulation.

Objectives Mitophagy is an important mitochondrial quality control mechanism. In this study, we investigated the mitochondrial damage and mitophagy occurred in inflammatory human dental pulp and lipopolysaccharide-stimulated preodontoblasts. Materials and methods In dental pulp tissues and lipopolysaccharide-stimulated preodontoblasts, immunofluorescences and Western blot were performed to detect the expression of mitochondrial and mitophagy-related proteins, and autophagy markers were also examined. Reactive oxygen species generated by mitochondria were examined by MitoSOX. Transmission electron microscope (TEM) was used to examine the morphology of mitochondria in lipopolysaccharide-stimulated preodontoblasts. Results The active fission activity of mitochondria and mitophagy in inflammatory dental pulp was observed. In lipopolysaccharide-treated preodontoblasts, mitophagy-related proteins were also upregulated. Moreover, increased reactive oxygen species in the inflamed preodontoblasts were observed. Additionally, single-membrane autolysosomes containing partially degraded mitochondria with swollen inner membranes in lipopolysaccharide-treated preodontoblasts were observed by TEM. Conclusions These results indicate that mitochondria were damaged and mitophagy might be activated to degrade impaired mitochondria in inflamed odontoblasts.

Fine particulate matter 2.5 (PM2.5) induces free radicals and oxidative stress in animals, leading to a range of illnesses. In this study, Ganoderma Microsporum immunomodulatory (GMI) proteins were administered to alleviate PM2.5-induced inflammatory responses in mother rats, and PM2.5-induced inflammatory responses and neurological damage in their offspring. The results suggested that GMI administration decreased the risk of neurological disorders in mother rats and their offspring by reducing the white blood cell count, lessening inflammatory responses and PM2.5-induced memory impairment, and preventing dendritic branches in the hippocampi from declining and microRNAs from PM2.5-induced modulation.

Periapical lesions are the distinct result of chronic root canal infection and could generate severe bone resorption surrounding apical regions. Despite the local cytokine and cell-mediated immune responses, periapical lesions are also characterized by its auto-restrict inflammation. However, the detailed mechanism related to its auto-restriction of immune response is still unclear. Co-inhibitory immune checkpoints are important molecules which could negatively modulate immune response especially in T cell function. In this study we detected the expressional pattern of PD-1/LAG-3 in periapical lesions. Immunohistochemical staining showed that the inflammatory response including up-regulation of TNF-α and the infiltration of T cells, was severe in granuloma and restricted in periapical cyst. PD-1 and LAG-3 both could be detected in granuloma and cyst, while scarcely observed in control group. Exhausted T cells, characterized by PD-1 or LAG-3 positive, accumulated within granuloma and reduced in cyst. Our study revealed that in periapical lesions, T cell exhaustion characterized by PD-1 or LAG-3 positive, might contribute to the auto-restriction of inflammatory response in periapical lesions.

As the characteristic size of the transistor approaches to its physical limit, the effect of impurities on device performance becomes more and more significant. The number of impurities and the range of impurity fluctuation become very limited in channel space less than 10 nm, and ionized impurities in local nano-space can even exhibit quantum dot characteristics, providing two discrete levels for charge transport. The behaviour of carrier tunnelling through quantum dots induced by ionized impurities can reveal the abundant quantum information, such as impurity ionization energy, coulomb interaction energy, electron activation energy, orbital level filling, and spin of local electrons. Quantum transport properties are also different in different doping concentrations because whether the quantum states overlap depends on the impurity atom spacing. The silicon nanostructure transistors using impurity atoms as building blocks of quantum transport are also called dopant atom transistors, which are not only compatible with complementary metal oxide semiconductor (CMOS) technology, but also expected to be the basic components of quantum computing circuits in the future. So far, their operating temperature is relatively low due to the shallow ground state energy level of impurity atoms. It is of great significance to study the quantum transport properties in dopant atom transistors and to observe quantum effects among them at room temperature. In this article, the quantum transport properties in single, discrete and coupled impurity atomic systems are described in detail by combining Anderson localization theory and Hubbard band model. Quantum transport in a discrete impurity atomic system is not only controlled by gate voltage, but also dependent on temperature. The current transport spectrum in the coupled impurity atomic system reveals more complex quantum dot characteristics. Single atom transistor can regulate quantum transport only by one impurity atom, which represents the ultimate scale limit of solid state devices. In addition, the methods of improving the operating temperature of dopant atom transistors are also systematically introduced, thereby laying a foundation for their practical applications.

The speed-adjustable system of asynchronous motor has been widely used in industrial production. in motor control, magnetic control is a key problem, but in order to realize the control of motor, magnetic field must be tested. The testing methods about rotor flux according to the rotor field-oriented control of motor are discussed in this paper. The paper describes the present two rotor flux calculation models: Voltage model and Current model. It concretely analyzes mathematical expressions of these two models in different coordinates, and realizes the matlab simulation of two kinds of model, the simulation results are compared by observations of the magnetic chain calculation results.

The transmiss on time and tunneling probability of an electron through a double quantum dot are studied using the transfer matrix technique. The time-dependent Schrodinger equation is applied for a Gaussian wave packet passing through the double quantum clot. The numerical calculations are carried out for a double quantum clot consisting of GaAs/InAs material. We find that the electron tunneling resonance peaks split when the electron transmits through the double quantum dot. The splitting energy increases as the distance between the two quantum dots decreases. The transmission time can be elicited from the temporal evolution of the Gaussian wave packet in the double quantum dot. The transmission time increases quickly as the thickness of tire barrier increases. The lifetime of the resonance state is calculated tram the temporal evolution of the Gaussian-state at the centers of quantum dots.

Although it has been suggested that hepatitis delta virus (HDV) can be used as a vector to deliver biologically active RNAs into hepatocytes, modified HDV as a specific transporting and replicating vector in anti-viral research has not been investigated. In this study, we focused on the development of HDV as a replicative vector to deliver hammerhead ribozyme into hepatocytes and the study of the roles of delivered hammerhead ribozyme on the replication of hepatitis B virus (HBV). To investigate the effects of ribozyme delivered by HDV on HBV replication, we designed two hammerhead ribozymes that specifically target the hepatitis B virus genome. These two ribozymes were then inserted into the genome of hepatitis delta virus. Results showed that transfection of cells with tandem modified HDV cDNA resulted in the production of monomer form of sense and anti-sense genomic RNA indicating the recombinant HDV-ribozyme could replicate effectively. Our data also indicated that ribozymes delivered by the modified HDV had higher level of inhibition activity against HBV replication than that of ribozyme alone. This system provides a new approach for the study of mechanisms of HBV replication as well as for the potential treatment of HBV infection.

We present a novel method for determining semiconductor parameters such as diffusion length L, lifetime tau and surface recombination velocity S of minority carriers by employing scanning electron microscopy (SEM). This new method is applicable to both electron beam induced current (EBIC and surface electron beam induced voltage (SEBIV) modes in SEM. The quantitative descriptions for EBIC and SEBIV signals are derived. The parameters L, S and tau can be directly extracted from the expressions for EBIC or SEBIV signals and their relaxation characteristics in experiment. As an example, the values of L, S and tau for n-p junction and p-Si crystal are determined by using the novel method in EBIC or SEBIV mode. The carrier diffusion length of a p-Si crystal is determined to be 8.74 mum in SEBIV mode. It is very close to the normal diffusion length of 7.41 mum of this sample. The novel method is proved to be very helpful for the quantitative characterization of semiconductor materials and devices. Especially, the SEBIV mode in SEM shows great potential for investigating semiconductor structures nondestructively.

In the framework of the effective-mass and adiabatic approximations, by setting the effective-mass of electron in the quantum disks (QDs) different from that in the potential barrier material, we make some improvements in the calculation of the electronic energy levels of vertically stacked self-assembled InAs QD. Comparing with the results when an empirical value was adopted as the effective-mass of electron of the system, we can see that the higher levels become heightened. Furthermore, the Stark shifts of the system of different methods are compared. The Stark shifts of holes are also studied. The vertical electric field changes the splitting between the symmetric level and the antisymmetric one for the same angular momentum.

A key issue in physical-layer network coding (PLNC) is how to recover the network-coded packet by the relay from the superimposed signals transmitted simultaneously by multiple transmitters. In order to decode correctly, the asynchrony between signals must be perfectly dealt with. That is, symbols transmitted by different transmitters could arrive at the receiver with relative carrier frequency offset (CFO), relative carrier phase offset and different channel fading. In this paper, we propose an algorithm to estimate the relative carrier offset from the PLNC signals, and investigate two decoding schemes, JCNC and M-JCNC, to construct the XORed packet. As shown in the simulation results, the algorithm can efficiently estimate the relative carrier offsets and significantly reduce the SNR penalty due to asynchrony.

Nano-vanadium dioxide thin films were prepared through thermal annealing vanadium oxide thin films deposited by dual ion beam sputtering. The nano-vanadium dioxide thin films changed its state from semiconductor phase to metal phase through heating by homemade system. Four point probe method and Fourier transform infrared spectrum technology were employed to measure and anaylze the electrical and optical semiconductor-to-metal phase transition properties of nano-vanadium dioxide thin films, respectively. The results show that there is an obvious discrepancy between the semiconductor-to-metal phase transition properties of electrical and optical phase transition. The nano-vanadium dioxide thin films' phase transiton temperature defined by electrical phase transiton property is 63 degrees C, higher than that defined by optical phase transiton property at 5 microm, 60 degrees C; and the temperature width of electrical phase transition duration is also wider than that of optical phase transiton duration. The semiconductor-to-metal phase transiton temperature defined by optical properties increases with increasing wavelength in the region of infrared wave band, and the occuring temperature of phase transiton from semiconductor to metal also increases with wavelength increasing, but the duration temperature width of transition decreases with wavelength increasing. The phase transition properties of nano-vanadium dioxide thin film has obvious relationship with wavelength in infrared wave band. The phase transition properties can be tuned through wavelength in infrared wave band, and the semiconductor-to-metal phase transition properties of nano vanadiium dioxide thin films can be better characterized by electrical property.

In this paper we study the SWAP operation in a two-qubit anisotropic XXZ model in the presence of an inhomogeneous magnetic field. We establish the range of anisotropic parameter lambda within which the SWAP operation is feasible. The SWAP errors caused by the inhomogeneous field are evaluated.

The electrical characteristics of Cu and Ni/Al AlGaN/GaN Schottky barrier diodes on Si substrates are compared. The onset voltage of Cu Schottky diodes is about 0.4V less than the Ni/Al contact. For the Cu/Ni Schottky contact, the leakage current is 4.7 × 10?7 A/mm at ?10 V. After annealing, the leakage current is decreased to 3.7 × 10?7 A/mm for 400?C or 4.6 × 10?8 A/mm for 500?C, respectively. The electrical property is affected by the thickness ratio of Cu to Ni. The Cu/Ni for 80/20 nm shows a low onset voltage, while the Cu/Ni for 20/80 nm shows a low leakage current. Both breakdown voltages are above 720 V.

To develop HDV as a vehicle to deliver hammerhead ribozyme into hepatocytes, the effects of modified HDV was assessed on the activity of embedded hammerhead ribozyme in vitro and in vivo.In vitro activity of ribozyme or HDV-driven ribozyme was assessed by incubating with the [alpha-32 P]-ATP labeled HBV RNA substrates at different temperature. Huh-7 cells were cotransfected with ribozyme or HDV-ribozyme chimera and HBV genome, by which inhibition of ribozymes on HBV transcription in vivo were examined.The results indicated that both temperature and secondary structure influenced the cleavage activity of HDV-driven ribozyme significantly. When the factors were eliminated, the HDV-driven ribozyme could act as well as its counterpart naked ribozyme. While in cultured cells the HDV-driven ribozyme had higher inhibition to HBV gene expression than that of ribozyme alone.The results demonstrated that HDV may weaken the activity of embedded ribozyme in vitro, but make it enhanced in cultured cells. Thus, this study could provide a useful evidence to develop HDV as vector for liver-special delivery of ribozyme to against chronic HBV infection.

We studied, for the first time, the strong coupling between exciton and cavity mode within semiconductor microcavity under hydrostatic pressure, and measured the Rabi splitting. The strong coupling between exciton and cavity mode, and so Rabi splitting appear clearly as the applied pressure reaches 0.37-0.41 GPa. The experiment result shows that hydrostatic pressure not only can tune the coupling between exciton and cavity mode effectively, but also can keep exciton property almost unchanged during the whole tuning procedure in contrast to other tuning method (temperature field et al). Our result agrees with the related theory very well. The Rabi splitting, extracted from fitting the measured mode-energy vs pressure curves with correspending theoretical model, is equal to 6 meV.

When injected electrons in a quantum well first experience an intersubband relaxation process before their escaping by tunneling through a double-barrier structure behind, the magnetic suppression of intersubband LO or LA phonon scattering can give rise to a noticeable nonthermal occupation in higher-lying subbands. That is clearly verified by the relative intensity ratio of the interband photoluminescence spectra for E2-HH1 and E1-HH1 transitions. The observed phenomenon may provide an effective method for controlling intersubband scattering rate, a central issue in so-called quantum cascade lasers, and facilitating the population inversion between subbands in quantum wells.

We provide a general, necessary, and sufficient condition for the possibility of transforming a mixed bipartite Gaussian state with arbitrarily many modes to another one under arbitrary local Gaussian channels, which do not include classical communication. Moreover, by means of this condition we present a necessary criterion that can be used to check the possibility of a state transformation between two mixed Gaussian states. At the same time, we prove that our criterion can be reduced to the Eisert-Plenio criterion when the mode number is chosen as 1 per side.

Overexpression of procollagen gene can cause the extraordinary increase of collagen's synthesis and therefore lead to the keloid and hypertrophic scar. To utilize ribozyme to suppress the expression of procollagen genes, a eukaryotic expression recombinant plasmid containing a dual-ribozyme gene against alpha 1 (I) and alpha 1 (III) procollagen genes was constructed. The ribozyme from in vitro transcription was incubated with target transcripts from recombinant plasmids which separately contained the fragments of the second exons of pro alpha 1 (I) and pro alpha 1 (III) collagen genes under various experimental conditions. The results showed that the dual-ribozyme could efficiently catalyze the specific cleavage of the target RNAs at 37 degrees C, 42 degrees C, 50 degrees C and Mg2+ concentration from 10 mmol/L to 20 mmol/L. This work provided a basis for further study on the ribozyme to suppress the expression of procollagen genes and control the cicatrization.

Hepatocyte growth factor (HGF) is a multifunctional growth factor which is a heterodimeric glycoprotein molecule. There are three truncated HGF variants: NK1, NK2, NK4. The structure of the promoter of HGF is very complicated, and the expression of HGF is regulated by various factors and regulatory elements. Because of the importance of HGF to human body, the genetic engineering expression and gene therapy investigation of HGF are being done.

The optimal entanglement manipulation for a single copy of mixed states of two qubits is to transform it to a Bell diagonal state. In this paper we derive an explicit form of the local operation that can realize such a transformation. The result obtained is universal for arbitrary entangled two-qubit states and it discloses that the corresponding local filter is not unique for density matrices with rank $n=2$ and can be exclusively determined for that with $n=3$ and 4. As illustrations, a four-parameters family of mixed states are explored, the local filter as well as the transformation probability are given explicitly, which verify the validity of the general result., Comment: 5 pages, to be published in Phys. Rev. A

From a cDNA library made from venom glands of Chinese scorpions of Buthus martensii Karsch, full-length cDNAs encoding precursors of two venom peptides have been isolated using a cDNA probe synthesized by polymerase chain reaction. Sequence analysis of the cDNAs revealed that one encoded precursor was 85 amino acid residues long including a signal peptide of 19 residues and a mature peptide (named BmK T) of 66 residues, and another encoded precursor was 84 residues long containing the same length signal peptide and a mature peptide (BmK M4 isoform, named BmK M4′) of 64 residues. The analysis of amino acid sequence similarity indicated that the BmK T was homologous with both mammalian and insect toxins from BmK scorpion or other scorpions, and the BmK M4′ was highly homologous with the members of the mammalian neurotoxin family of BmK, having two point mutations in amino acid residue sequence compared to BmK M4, a natural toxin from BmK.

We investigated the transmission probability of a single electron transmission through a quantum ring device based on the single-band effective mass approximation method and transfer matrix theory. The time-dependent Schrodinger equation is applied on a Gaussian wave packet passing through the quantum ring system. The electron tunneling resonance peaks split when the electron transmits through a double quantum ring. The splitting energy increases as the distance between the two quantum rings decreases. We studied the tunneling time through the single electron transmission quantum ring from the temporal evolution of the Gaussian wave packet. The electron probability density is sensitive to the thickness of the barrier between the two quantum rings. (C) 2008 American Institute of Physics.

The characteristic differences in nonresonant magnetotunneling processes measured from a number of asymmetric GaAs/AlAs double-barrier resonant-tunneling structures under two opposite biases have systematically been studied, and ascribed to the different dwell times of traversing electrons in the well as they tunnel in opposite directions.