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Objective: To explore the correlations of integrons, gene cassettes and drug resistance phenotypes in 90 multi-drug resistant Gram-negative bacteria., Methods: Class I/II/III integron and variable region of positive strains of 90 Gram-negative bacteria were amplified by PCR and types of integron variable region gene cassettes analyzed by DNA sequence. And the resistant rates of integron positive and negative strains were tested by drug susceptibility., Results: The detection rate of integron was 81.1% (73/90) in 90 Gram-negative bacteria. The integron types were class I (n = 70), class II (n = 3) and class III (n = 0). Based on the BLAST analysis by GenBank database, in the amplified fragments of Class I integron positive strains variable region gene ranging from 730 to 3300 bp, 8 types of integron structure were identified. And there were aadB (n = 11), aac (6')-II (n = 7), aadA5 (n = 10), dfrA17-aadA5 (n = 14), dfrA12-OrfF-aadA2(n = 1), aacA4-catB8-aadA1(n = 24), aacC1-OrfA-OrfB-aadA1 (n = 3), catB3-aadB-dhfrV-aacA4-nit1-nit2 (n = 1), in which catB3-aadB-dhfrV-aacA4-nit1-nit2 was a new resistance gene cassette; the variable region fragment of class II integron positive strain was 1600 bp, with 3 carrier strains of sat2-aadA1 gene cassette.Susceptibility testing showed that the antimicrobial resistance rate of integron positive strains to aminoglycosides and sulfa were significantly higher than those of integron negative strains and accorded with the results of integration variable region gene cassettes; the positive strains were more sensitive to amikacin with a resistance rate of 32.9% (24/73); and the drug resistance rates of all beta-lactam strains were ≥ 80%., Conclusions: There is a higher carrier rates of classI integron in Gram-negative bacteria. And the resistant phenotype is related with the types of resistance gene cassettes of integron variable region.

To improve the accuracy of quantitative analysis in laser-induced breakdown spectroscopy, the plasma produced by a Nd:YAG laser from steel targets was confined by a cavity. A number of elements with low concentrations, such as vanadium (V), chromium (Cr), and manganese (Mn), in the steel samples were investigated. After the optimization of the cavity dimension and laser fluence, significant enhancement factors of 4.2, 3.1, and 2.87 in the emission intensity of V, Cr, and Mn lines, respectively, were achieved at a laser fluence of 42.9 J/cm(2) using a hemispherical cavity (diameter: 5 mm). More importantly, the correlation coefficient of the V I 440.85/Fe I 438.35 nm was increased from 0.946 (without the cavity) to 0.981 (with the cavity); and similar results for Cr I 425.43/Fe I 425.08 nm and Mn I 476.64/Fe I 492.05 nm were also obtained. Therefore, it was demonstrated that the accuracy of quantitative analysis with low concentration elements in steel samples was improved, because the plasma became uniform with spatial confinement. The results of this study provide a new pathway for improving the accuracy of quantitative analysis of LIBS.

Objective: To screen for potential mutations in an ethnic Han Chinese family from Shanxi with hereditary multiple exostoses., Methods: Polymerase chain reaction and DNA sequencing were used to screen potential mutations in EXT1 and EXT2 genes., Results: For EXT1 gene, two synonymous mutations (P477P and E587E), three intronic mutations (c.1537 -48A>G, c.1721 +203A>G and c.1722 -103C>G) were detected. For EXT2 gene, five intronic mutations (c.-29 -148A>T, c.1080 -18T>A, c.1336 -93C>T, c.1526 -166C>T, and c.1526 -195C>T) were identified. Among these, EXT1 P477P, EXT1 E587E and EXT2 c.1080 -18T>A are polymorphisms listed by Multiple Osteochondroma Mutation Database, whilst the other 7 sites have not been reported., Conclusion: No mutations have been found among all exons of the EXT1 and EXT2 genes in this family. Linkage analysis is necessary for identifying the cause of this disease.

Taking the 5 hm2 sampling plot in the natural secondary poplar-birch forest in Changbai Mountains as test object, and based on the two census data in 2005 and 2010, an analysis was made on the main tree species composition and quantity, size class distribution of dead individuals, and regeneration characteristics of the main tree species in different habitat types of the plot in 2005-2010. In the five years, the species number of the individuals with DBH> or = 1 cm increased from 46 to 47, among which, 3 species were newly appeared, and 2 species were disappeared. The number of the individuals changed from 16509 to 15027, among which, 2150 individuals died, accounting for 13% of the whole individuals in 2005, and 668 individuals were newly increased. The basal area of the trees increased from 28.79 m2.m-2 to 30.55 m2.m-2, with that of 41 species increased while that of 6 species decreased. The decrease of the basal area of Betula platyphylla and Populus davidiana accounted for 72.3% of the total decrease. Small individuals had higher mortality, as compared with large ones, and the mortality of the individuals with DBH<5 cm occupied 65% of the total. B. platyphylla and P. davidiana contributed most in the dead individuals with large DBH. No difference was observed in the tree mortality among different habitat types, but the mortality of the individuals with different size classes showed greater variation.

Laser induced plasma spectroscopy of alloy steel was produced by Nd : YAG pulsed laser at 1 064 nm, and the spectral signal was detected by high resolution and width controlled ICCD. Several Fe atomic spectral lines such as 404.581, 414.387, 427.176 and 438.355 nm were chosen for analysis, and the effects of different experimental parameters on LIBS spectral signal intensity were investigated. It is shown that the experimental parameters such as pulse energy, laser focus location and laser delay time have great influence on the LIBS signal. LIBS signals with high spectral intensity and signal-background ratio (SBR) as well as the optimum experiment conditions were obtained by optimizing these experiment parameters so as to make composition analysis of the alloy steel.

Objective: To explore the diagnosis and treatment of focal nodular hyperplasia (FNH) of liver., Methods: The clinical data were retrospectively analyzed for 26 cases with confirmed FNH of liver from January 2006 to July 2011. Enhanced computed tomography and magnetic resonance imaging were performed., Results: Among them, 22 cases underwent surgical resection, including left hemihepatectomy (n = 4), left lateral lobe hepatectomy (n = 5) and partial hepatectomy (n = 13). The pathological diagnosis was FNH. Most tumors were of soft texture. The gross surface was brown or yellow-brown in color. Central scar and radiating fibrous septas were spotted in some cases. There was no recurrence during a follow-up period of 4 months to 5 years. Serial observations were conducted for 4 cases with a follow-up period of 2 - 4 years. No growth was observed., Conclusions: Enhanced CT and MRI are important diagnostic tools. The confirmed cases may be followed up. Surgical resection is effective with an excellent prognosis.

Because of the potential impact on agriculture and other key human activities, efforts have been dedicated to the local control of precipitation. The most common approach consists of dispersing small particles of dry ice, silver iodide, or other salts in the atmosphere. Here we show, using field experiments conducted under various atmospheric conditions, that laser filaments can induce water condensation and fast droplet growth up to several μm in diameter in the atmosphere as soon as the relative humidity exceeds 70%. We propose that this effect relies mainly on photochemical formation of p.p.m.-range concentrations of hygroscopic HNO(3), allowing efficient binary HNO(3)-H(2)O condensation in the laser filaments. Thermodynamic, as well as kinetic, numerical modelling based on this scenario semiquantitatively reproduces the experimental results, suggesting that particle stabilization by HNO(3) has a substantial role in the laser-induced condensation.

A multiwavelength, multicomponent CRDS gas sensor operating on the basis of a compact photonic crystal fibre supercontinuum light source has been constructed. It features a simple design encompassing one radiation source, one cavity and one detection unit (a spectrograph with a fitted ICCD camera) that are common for all wavelengths. Multicomponent detection capability of the device is demonstrated by simultaneous measurements of the absorption spectra of molecular oxygen (spin-forbidden b-X branch) and water vapor (polyads 4v, 4v + δ) in ambient atmospheric air. Issues related to multimodal cavity excitation, as well as to obtaining the best signal-to-noise ratio are discussed together with methods for their practical resolution based on operating the cavity in a "quasi continuum" mode and setting long camera gate widths, respectively. A comprehensive review of multiwavelength CRDS techniques is also given.

In order to understand the composition and spatiotemporal dynamics of the litter falls at community level in a broad-leaved Korean pine mixed forest in Changbai Mountains, litter falls were collected from 150 containers in a 25 hm2 permanent plot in 2008. The leaf litters in the containers were from 35 tree species, accounting for 67.3% of the total number (52) of the tree species with DBH > or =1 cm in the plot. The litter falls had a weight 29.39 kg, equivalent to 3918.4 kg x hm(-2) among which, broad leaves, miscellany, needle leaves, and branches occupied 61.7%, 18.0%, 11.7%, and 8.6%, respectively. About 83.8% of the broad leaves were from Tilia amurensis, Fraxinus mandshurica, Quercus mongolica, Acer mono, and Ulmus japonica. The litter falls showed an evident seasonal dynamics, with the peaks occurred from 13 September to 10 October, e.g., the litter falls from T. amurensis and Pinus koraiensis peaked in 13-26 September, while those from Q. mongolica, U. japonica, and A. pseudo-sieboldianum peaked in 27 September to 10 October. There was a great difference in the mass of the litter falls among the containers, e.g., with 150-200 g litters in 68 containers and >500 g litters in 1 container. The species number of the litter falls in a container was 18 in maximum, and was 12 in common (32 containers). Litter falls mass was positively proportional to the sum of the basal area at breast height of parent trees in the plot, and the amount of the litter falls in the containers was related with the locations of the containers, exhibiting an evident spatial heterogeneity in the plot.

Based on the shrub census of 600 quadrats (5 mx5 m) in a 25 hm2 plot of broad-leaved Korean pine mixed forest in Changbai Mountains, this paper analyzed the species composition, structure, and spatial distribution of shrubs in the forest. A total of 18 shrub species, including 6435 shrub individuals and 11369 stems, were found in the census, with Philadelphus schrenkii, Corylus mandshurica, and Acer barbinerve being the dominant species. P. schrenkii had the highest amounts of individuals and stems, occupying 40.6% and 33.4% of the total, respectively. There existed great differences in the clumpy ratio, stem number per clump, crown size, and basal diameter among the shrub species, and the height of different shrub species also varied significantly, with obvious vertical stratification observed in the community. The dominant species P. schrenkii had a wide distribution, while Sorbaria sorbifolia, Spiraea chamaedryfolia, S. salicifolia, and Euonymus pauciflorus had obvious heterogeneous distributions.

Short lived plasma channels generated through filamentation of femtosecond laser pulses in air can be revived after several milliseconds by a delayed nanosecond pulse. Electrons initially ionized from oxygen molecules and subsequently captured by neutral oxygen molecules provide the long-lived reservoir of low affinity allowing this process. A Bessel-like nanosecond-duration laser beam can easily detach these weakly bound electrons and multiply them in an avalanche process. We have experimentally demonstrated such revivals over a channel length of 50 cm by focusing the nanosecond laser with an axicon.

The triggering and guiding of the stationary high voltage (HV) discharges at 5-40 kV are demonstrated by using plasma filaments generated by single and dual femtosecond(fs) laser pulses in air. A significant reduction of the breakdown voltage threshold due to the pre-ionization of the air gap by laser pulse filamentaion was observed. The amount of free electrons of filaments generated by different pulse configurations was compared by sonography method. The lifetime of filaments is measured by using time-resolved fluorescence spectrum, and the lifetime of filaments generated by dual fs laser pulses was doubled due to the re-ionization by the succeeding pulse. The triggering ability of dual fs laser pulses was demonstrated to be enhanced due to the longer lifetime of filaments.

Aiming at the variation of precipitation pattern caused by global warming, a field simulation experiment was conducted to study the effects of 30% increase (+W) and decrease (-W) of precipitation on the morphology, growth, and biomass partitioning of mono- and mixed cultured seedlings of Quercus mongolica and Pinus koraiensis, the two dominant tree species in temperate broad-leaved Korean pine mixed forest in Changbai Mountains. Comparing with monoculture, mixed culture increased the canopy width and main root length of Q. mongolica seedlings, but decreased the basal diameter, plant height, leaf number, and dry masses of root, stem, leaf and whole plant of P. koraiensis seedlings significantly. Treatment (-W) increased the stem/mass ratio while decreased the main root length of Q. mongolica seedlings, and decreased the main root length, leaf number, dry masses of leaf and whole plant, and leaf/mass ratio, while increased the stem/mass ratio of P. koraiensis seedlings significantly, compared with treatment CK. Treatment (+W) had no significant effect on these indices of the two species. At early growth stage, interspecific competition and precipitation pattern had significant effects on the morphology and growth of the seedlings, and the responses were much stronger for P. koraiensis than for Q. mongolica.

An investigation from 2006 to 2007 was made on the Pinus koraiensis seed consumption by rodents and birds in the broad-leaved P. koraiensis mixed forest and birch forest at the same altitude in Changbai Mountains. The results showed that in broad-leaved P. koraiensis mixed forest, rodents consumed more pinecone seeds than birds; while in birch forest, birds did more than rodents. In the two forests, the total number of pinecone seeds consumed by rodents was significantly higher than that consumed by birds (P < 0.01). In addition, rodents consumed more embedded seeds in broad-leaved P. koraiensis mixed forest than in birch forest, and the consumption amount in the two forests decreased with increasing embedded depth.

PnET-II (photosynthesis and evapotranspiration) model is an ecosystem process model, which requires extensive input parameters, including vegetation parameters, soil parameters and climate parameters, to simulate net primary productivity (NPP). This study estimated the total and wood (stem and branch) NPPs of Korean pine and broadleaf species in Fenglin Natural Reserve, and examined the responses of the NPPs to the variations of the input parameters in PnET-II model. The simulation results indicated that among the vegetation parameters in PnET-II model, the variation of canopy parameters, had greater effects on the simulated NPPs of Korean pine and broadleaf species, and the response of Korean pine's total NPP to vegetation parameters was larger than that of broadleaf species'. The variation of soil water holding capacity (WHC) had smaller effects on the NPPs of Korean pine and broadleaf species, and the response of Korean pine's NPP to the WHC was somewhat smaller than that of broadleaf trees'. In climate scenarios, the variation of air temperature had the greatest effects on the simulated NPP of Korean pine and broadleaf trees, followed by precipitation and radiation. Different climate scenarios had different effects on the predicted results. The total and wood NPPs of Korean pine and broadleaf trees had different responses to the input parameters.

In this paper, the species composition, seasonal dynamics, and spatial distribution patterns of herbs were examined in a 25 hm2 broadleaved Korean pine (Pinus koraiensis) mixed forest plot in Changbai Mountains. The results showed that the plot had a relatively high herbaceous richness, with 102 species belonging to 40 families and 84 genera, and the Shannon index, Simpson index, and Pielou index was 3.52, 0.96 and 0.75, respectively. The three indices varied dramatically with growth season, whereas the species abundance decreased linearly from early spring to autumn. The species richness and abundance showed irregular distribution, indicating that herbaceous species were microenvironment-dependent. Slope aspect had significant effects on herbaceous species richness and abundance. Northern and eastern slopes had higher species richness and abundance in early spring than southern and western slopes, whereas it was in adverse in late summer and autumn.

The propagation of a tightly focused femtosecond laser pulse in air has been investigated. Unlike long-distance self-guided propagation of short laser pulses, a novel oval-like hollow distribution of the laser intensity is observed in the experiments and reproduced by the numerical simulations. The formation of the hollow structures can be explained by the interplay between ionization-induced refraction and Kerr self-focusing.

The robustness and prolongation of multiple filamentation (MF) for femtosecond laser propagation in air are investigated experimentally and numerically. It is shown that the number, pattern, propagation distance, and spatial stability of MF can be controlled by a variable-aperture on-axis pinhole. The random MF pattern can be optimized to a deterministic pattern. In our numerical simulations, we configured double filaments to principlly simulate the experimental MF interactions. It is experimentally and numerically demonstrated that the pinhole can reduce the modulational instability of MF and is favorable for a more stable MF evolution.

Ecological assets assessment is of great significance in building harmonious society and implementing scientific concept of development. Based on the achievements in ecological assets assessment research, the concept and scope of ecological assets were re-examined, and the contents of ecological assets assessment were summarized in this paper. It was considered that ecosystem quality, ecosystem pressure and ecological assets value should be the focus in assessing ecological assets. With the ecological assets assessment on forest ecosystem as an example, some referenced indicators and calculation models were given. By the end of the paper, some suggestions on the further study were presented.

Based on the investigation data from a 25 hm2 broadleaved Korean pine (Pinus koraiensis) mixed forest plot in Changbai Mountains of China, the dominant species Korean pine and Tilia amurensis were chosen as research objects. One point pattern analysis method, O-ring statistics, was used to analyze the spatial patterns of the species in three vertical layers, i. e., overstory, midstory and understory layers, and the spatial associations of intra- and inter-species between different vertical layers were studied. The results showed that P. koraiensis and T. amurensis were clumped at smaller scales. Higher layers tended to be randomly or regularly distributed, while lower layers tended to be aggregated at smaller scales. The aggregation degree decreased with canopy height. P. koraiensis stems in overstory layer were significantly positively associated to the stems in midstory layer at scales < 11 m, and T. amurensis in overstory layer showed negatively correlation with that in midstory and understory layers. There was generally a positive correlation between the two species, but the association varied among different layers. No significant correlation was observed between P. koraiensis stems in overstory layer and T. amurensis in three layers. P. koraiensis stems in midstory layer showed slightly negative correlation with T. amurensis in the same layer at scales > 4 m, but no significant association to T. amurensis in understroy layer. T. amurensis in overstory layer was significantly positively associated to P. koraiensis in midstory layer at scales < 100 m.

The spatial evolution of plasma filaments in air induced by femtosecond laser pulses is investigated experimentally. Several major filaments and small scaled additional filaments are detected in the plasma channel. The complicated interaction process of filaments as splitting, fusion and spreading is observed. The major filaments propagate stably, and the small scaled additional filaments can be attracted to the major filaments and merged with them. The major filaments are formed due to the perturbation of initial beam profile and the small scaled filaments are mainly caused by the transverse modulational instability.

A long plasma channel, formed due to the dynamic balance between the nonlinear self-focusing and the plasma defocusing in the propagation of intense femtosecond laser pulses in air, is demonstrated to be able to continuously propel a paper airplane without complicated focusing optics. The maximum coupling coefficient generated by the plasma channel is found to be more than 8.5 dyne/W. In the plasma channel, the detonation wave generation with the air ionization is found to be the propulsive source.

Objective: To investigate changes of two sodium channels, PN(3) and NaN, during orofacial pain by occlusal trauma in rat., Methods: Expressions of PN(3) mRNA and NaN mRNA in trigeminal ganglion were tested during various periods of persistent occlusal trauma with reverse transcription-polymerase chain reaction (RT-PCR)., Results: In groups, including control, occlusal trauma groups, PN(3) mRNA and NaN mRNA were all expressed in trigeminal ganglion neurons. In the control group, there were similar density values bilaterally. In the occlusal trauma group, the density values in gel electrophoresis of PN(3) mRNA and NaN mRNA on the intervention side were slightly greater than those on the control side., Conclusions: The stimulation of occlusal trauma upregulates expressions of PN(3) mRNA and NaN mRNA, which suggests the signal occurring and conduction of chronic pain by occlusal trauma have the same molecular mechanism of sodium channel as inflammatory pain.

Objective: To study the effect of traumatic occlusion on CGRP-immunoreactive (CGRP-IR) nerve fibres in rat molar pulp and observe the recovery of CGRP-IR nerve fibres after removal of traumatic occlusion., Methods: To observe immunohistochemically the change of CGRP-IR nerve fibres in molar pulp during traumatic occlusion and after removal., Results: The increase of number, density and morphology of CGRP-IR nerve fibres in traumatic occlusion group was more than in control group, however, the changes of CGRP-IR nerve fibres in removal of traumatic occlusion group were less than in control group., Conclusions: The changes of CGRP-IR nerve fibres in number, morphology, and density are induced by traumatic occlusion in rat molar pulp, however, the nerve fibres recover to normal by removal of traumatic occlusion.

Objective: To investigate the frequencies distribution of GSTT1 and GSTM1 null genotypes in 24 Yunnan populations., Methods: GSTT1 and GSTM1 genotypes were analyzed by PCR procedure., Results: The range of frequencies for GSTT1 and GSTM1 null genotypes in the populations were 0.188-0.633 and 0.400-0.745, respectively, and in the districts were 0.286-0.583, 0.433-0.745 respectively. There was significant relationship between GSTT1 frequencies and populations., Conclusion: The frequencies of GSTT1 and GSTM1 null genotypes in 24 Yunnan populations were different, but they were almost the same in different districts of Yunnan.

Telemetering is one of the ideal methods of metering biomedical signal. This paper emphasizes remote medical treatment system and its exploitation, realization and application. It gives an overview of the recent development of biotelemetry. At the same time, it discusses the principle, realization, new development of other biotelemetry methods and further research tendencies on biotelemetry as well.

Collagen was extracted by pepsin digestion from porcine skin, and collagen membrane was prepared by salt precipitation. The porcine collagen membrane was evaluated as a burn wound dressing in deep partial skin thickness burn wounds in rats. Burn wounds, 4 x 4 cm, were inflicted by exposure of skin to 75 degrees C for 15 s followed by de-epithelialization. Wound healing was assessed by planimetry of epithelialization on day 10 after injury. Open wounds exhibited 24 per cent of wound area re-epithelialized. Collagen membrane dressing significantly improved the healing to 69 per cent of wound area (P < 0.0001). In a completely separate experiment, the porcine collagen membrane was applied as a wound dressing to the donor sites of burn patients, and its effect on wound healing was compared with that of a petroleum jelly gauze dressing. The donor sites covered with petroleum jelly gauze had re-epithelialized by an average of 14.5 days (ranging from 13 to 16 days) after wounding. The wounds dressed with collagen membrane demonstrated a significant increase in the healing rate. Complete re-epithelialization was observed by 10.3 days (ranging from 10 to 12 days) after wounding (P < 0.0001).

Since the supply of unburned autograft skin may be insufficient to cover very extensive burns, we have prepared allograft skin inoculated with a suspension of uncultured autogenous epithelial cells and grafted this material on to full skin thickness loss wounds. There was a satisfactory 'take' and permanent healing of this mixture of heterogeneous dermis and autogenous epidermis in two out of four patients. In this preliminary report we describe the clinical and histological observations which indicate that in the two patients with successful graft 'take' the epithelial cells proliferated and formed a continuous pale-coloured layer on top of the heterogeneous dermis between 30 and 40 days after application.