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As the cost of LiDAR equipment is high and different projects prefer different goals, the flying scheme needs to be strict planned to save cost and energy. In this study, LiDAR's ability at different flying height was tested. Two trials with different flying height are compared. Analysis was conducted by considering the relative accuracy, intensity and penetration ability to find out the difference of two trials. The result shows the relative accuracy between these two trials is 0.37 m. True relative accuracy is achieved when removing canopy as large interpolation errors often exist at places with great slope changes like the canopy. Intensity values decrease greatly with the increase of flying height due to the longer travel distance and more energy loss in atmosphere. Statistical results showed that in each trial high intensity is apt to be from low canopy and only return. LiDAR vegetation penetration ability decreased greatly at low vegetation due to the enlarged footprint and weakened energy, but it doesn't change on large vegetation.

Remediation action is critical for the management of polychlorinated biphenyl (PCB) contaminated sites. Dozens of remediation technologies developed internationally could be divided in two general categories incineration and non-incineration. In this paper, life cycle assessment (LCA) was carried out to study the environmental impacts of these two kinds of remediation technologies in selected PCB contaminated sites, where Infrared High Temperature Incineration (IHTI) and Base Catalyzed Decomposition (BCD) were selected as representatives of incineration and non-incineration. A combined midpoint/damage approach was adopted by using SimaPro 7.2 and IMPACTA2002+ to assess the human toxicity, ecotoxicity, climate change impact, and resource consumption from the five subsystems of IHTI and BCD technologies, respectively. It was found that the major environmental impacts through the whole lifecycle arose from energy consumption in both IHTI and BCD processes. For IHTI, primary and secondary combustion subsystem contributes more than 50% of midpoint impacts concerning with carcinogens, respiratory inorganics, respiratory organics, terrestrial ecotoxity, terrestrial acidification/eutrophication and global warming. In BCD process, the rotary kiln reactor subsystem presents the highest contribution to almost all the midpoint impacts including global warming, non-renewable energy, non-carcinogens, terrestrial ecotoxity and respiratory inorganics. In the view of midpoint impacts, the characterization values for global warming from IHTI and BCD were about 432.35 and 38.5 kg CO2-eq per ton PCB-containing soils, respectively. LCA results showed that the single score of BCD environmental impact was 1468.97 Pt while IHTI's score is 2785.15 Pt, which indicates BCD potentially has a lower environmental impact than IHTI technology in the PCB contaminated soil remediation process.

As the main source of inocula, ectomycorrhizal (ECM) fungal propagules are critical for root colonization and seedling survival in deforested areas. It is essential to know factors that may affect the diversity and composition of ECM fungal community on roots of seedlings planted in deforest areas during reforestation. We quantitatively evaluated the effect of host plant and soil origin on ECM fungal propagule community structure established on roots of Castanopsis fargesii, Lithocarpus harlandii, Pinus armandii, and Pinus massoniana growing in soils from local natural forests and from sites deforested by clear-cut logging in the 1950s and 1960s. ECM root tips were sampled in April, July, and October of 2006, and ECM fungal communities were determined using ECM root morphotyping, internal transcribed spacer (ITS)-RFLP, and ITS sequencing. A total of 36 ECM fungal species were observed in our study, and species richness varied with host species and soil origin. Decreased colonization rates were found in all host species except for L. harlandii, and reduced species richness was found in all host species except for P. armandii in soil from the deforested site, which implied the great changes in ECM fungal community composition. Our results showed that 33.3% variance in ECM fungal community composition could be explained by host plant species and 4.6% by soil origin. Results of indicator species analysis demonstrated that 14 out of 19 common ECM fungal species showed significant preference to host plant species, suggesting that the host preference of ECM fungi was one of the most important mechanisms in structuring ECM fungal community. Accordingly, the host plant species should be taken into account in the reforestation of deforested areas due to the strong and commonly existed host preference of ECM fungi.

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PCDD/Fs formation distribution in gas phase and solid phase of medical waste incineration fly ash under both the flowing nitrogen and static air condition were studied within temperature range of 200-450 degrees C. Under the flowing nitrogen, PCDD/Fs in solid phase increased with temperature increase, which reached the maximum concentration at 350 degrees C, both the TEQ and total concentration increased 46.0% and 26.0% respectively of original concentration, then, which decreased with temperature's rising, reaching the lowest level at 450 degrees C, of which 86.8% and 80.5% respectively in turn removed. Under the static air, the maximum concentration in solid phase occurred at 250 degrees C, both the TEQ and total concentration increased 20.7% and 28.7% respectively of original concentration, then, which decreased with temperature increase, reaching the lowest level at 450 degrees C, of which 99.5% and 99.5% respectively in turn removed. There were small generation of PCDD/Fs in gas phase, which took only 0.11%-2.16% of the total quantity of PCDD/Fs in both gas phase and solid phase. The optimal conditions for thermal treatment in this study were under the static air at temperature of 450 degrees C in duration of 1 h. The mechanism of destruction played the main role in the thermal treatment, while dechlorination and desorption acted as minor role in this study.

To establish an tachyzoite-brachyzoite interconversion system for Toxoplasma gondii RH strain in vitro.COS-7 cells were inoculated with purified tachyzoites of T.gondii RH strain and cultured in vitro. The morphology of the cultured cells and parasites was observed and the total cellular RNA extracted on days 1 to 6 following the inoculation for detecting the expression of tachyzoite-specific protein (SAG1) and bradyzoite-specific proteins (BAG1 and SAG2C) using RT-PCR.With the passage of time, the number of parasites in COS-7 cells increased but the proliferation rate was lowered gradually. The intracellular tachyzoites proliferated by means of budding and binary fission, which led to the changes in the alignment of the parasites in the cells from curved pairs, rosette or clustered, and semi-circular patterns to spherical encapsulation-like structures. These changes indicated the gradual transformation of the tachyzoites into bradyzoites. The expressions of the tachyzoite-specific SAG1 gene were detected throughout the 6 days of in vitro culture. The expression of the bradyzoite-specific BAG1 gene had been detected since the second day after the inoculation and SAG2C gene since the fifth day. Alteration of the culture condition resulted in gradual transformation of the bradyzoites into tachyzoites.An in vitro tachzoites-bradyzoite interconversion system for T.gondii has been successfully established, which provides the basis for further study of the mechanism of interconversion.

Molecules can enter the nucleus by passive diffusion or active transport mechanisms, depending on their size. Small molecules up to size of 50-60 kDa or less than 10 nm in diameter can diffuse passively through the nuclear pore complex (NPC), while most proteins are transported by energy driven transport mechanisms. Active transport of viral proteins is mediated by nuclear localization signals (NLS), which were first identified in Simian Virus 40 large T antigen and had subsequently been identified in a large number of viral proteins. Usually they contain short stretches of lysine or arginine residues. These signals are recognized by the importin super-family (importin α and β) proteins that mediate the transport across the nuclear envelope through Ran-GTP. In contrast, only one class of the leucine-rich nuclear export signal (NES) on viral proteins is known at present. Chromosome region maintenance 1 (CRM1) protein mediates nuclear export of hundreds of viral proteins through the recognition of the leucine-rich NES.

In previous study, we have identified a nuclear localization signal (NLS) and a nucleolar localization signal (NoLS) in bovine herpesvirus-1 (BHV-1) infected cell protein 27 (BICP27), which targets predominantly to the nucleolus. Furthermore, the C-terminal 300 amino acid residues targets exclusively to the cytoplasm, suggesting that BICP27 might contain a nuclear export signal (NES). Amino acid sequence analysis revealed that there is a cluster of leucine-rich residues resembling a NES. Heterokaryon assays demonstrated that BICP27 is capable of shuttling between the nucleus and the cytoplasm of the BHV-1 infected, BICP27 and BICP27-EYFP transfected cells. Deletion mutant analysis revealed that this property is attributed to the leucine-rich NES 299LEELCAARRLSL310. Moreover, the functional NES could mediate transport of a monomer EYFP and a dimer EYFP to the cytoplasm. The nucleocytoplasmic shuttling of BICP27 and the nuclear export of NES-EYFP and NES-dEYFP could be blocked by leptomycin LMB, an inhibitor of the chromosomal region maintenance 1 (CRM1), which is the receptor for exportin-1-dependent nuclear export. In addition, the nuclear import of BICP27 was inhibited by a dominant negative Ran-GTP, namely Ran-GTP Q69L, indicating that BICP27 localized to the nucleus by means of a classic Ran dependent nuclear import mechanism. In conclusion, these results demonstrate that BICP27 shuttles between the nucleus and the cytoplasm by the functional NES and NLS through a CRM1-dependent nuclear export pathway and a Ran dependent nuclear import pathway.

Nucleoside triphosphate hydrolase (NTPase) is an abundant protein secreted by the obligate protozoan parasite Toxoplasma gondii, which has a wide specificity toward NTP. In the present study, two monoclonal antibodies (mAbs, MNT1 and MNT2) against recombinant T. gondii NTPase-II (rTgNTPase-II) were developed. Western blot analysis displayed that these two mAbs can recognize specifically rTgNTPase-II as well as a 63kDa molecule in tachyzoites soluble antigens that corresponded to native NTPase-II. T. gondii tachyzoites pretreated with two mAbs were observed under Confocal Laser Microscope and a specific reaction was displayed on tachyzoites after indirect fluorescence antibody test (IFAT). When COS-7 cells were co-cultured with tachyzoites pretreated with two mAbs, the number of intracellular parasites per infected cell was significantly decreased compared with the control. Furthermore, incubation of T. gondii tachyzoites with two mAbs can inhibit NTPase activity in the presence of dithiothreitol, which hinted that the reduction of tachyzoite replication might be owing to the inhibition of NTPase-II by the mAbs. The passive immunization test indicated that the transferred mAbs can significantly prolong the survival time of challenge infected mice. Taken together, we concluded that the mAbs against NTPase-II can reduce the replication of T. gondii and have a crucial effect on the protection of host from T. gondii infection.

Trifluoroacetic anhydride is an effective promoter for the preparation of chitin single- and mixed-acid esters. Complete dissolution is achieved within 30 min when powdered chitin is heated at 70 degrees C in a mixed solution of carboxylic acid(s) and trifluoroacetic anhydride. Chitin esters prepared are chitin acetate, chitin butyrate, chitin hexanoate and chitin octanoate, chitin co-acetate/butyrate, chitin co-acetate/hexanoate, chitin co-acetate/octanoate, chitin co-acetate/palmitate, each from a solution of the respective reactants. The products have degrees of O-acyl substitution in a range of DS 1-2 depending on the nature of acyl group, as analyzed by gas-liquid and high-pressure liquid chromatography. Acetic acid as a mutual component for the mixed-acid esters increases the total degree of substitution, and the acetyl substitution is close to the relative distribution in the reaction mixture for chitin co-acetate/butyrate. It is favored over hexanoate, octanoate, and palmitate. The parent molecules, as calculated by the composition of the chitin esters and their molecular weights by light-scattering spectroscopy, are 30 kDa for the smallest and 150-151 kDa for the largest. Films of these chitin derivatives when cast from solution are strong and flexible with limited extensibility. By dynamic mechanical analysis of the ester film, it was found that both the glass transition temperature (T(g)) and the tensile modulus (E' at 25 degrees C) are highest for chitin acetate (218 degrees C and 5.8 GPa), and lowest for chitin octanoate (182 degrees C and 1.5 GPa). For the other esters, these values lie between the above-cited values, where the T(g) and the E' decrease with an increase in the chain length of the acyl constituent.

The quality of copper strips directly affects the performance and quality of copper and its products. So there is great significance to detect and recognize the surface defects in copper strips. The testing results from traditional manual inspection methods are unsatisfactory. So, this paper presents a novel recognition method of surface defects in copper strip based on fuzzy neural network. In this paper, the feature vectors of typical defects picked by the moment invariants form the neural network training samples and fuzzy wavelet neural network based on learning rate dynamically regulated BP algorithm identifies defects. Experiments show that this method can effectively detect surface defects in copper strips in the production line. Besides, it has a high recognition accuracy and speed.

To understand the temporal responses of soil prokaryotic communities to clear-cutting disturbance, we examined the changes in soil bacterial and archaeal community composition, structure and diversity along a chronosequence of forest successional restoration using high-throughput 16S rRNA gene sequencing. Our results demonstrated that clear-cutting significantly altered soil bacterial community structure, while no significant shifts of soil archaeal communities were observed. The hypothesis that soil bacterial communities would become similar to those of surrounding intact primary forest with natural regeneration was supported by the shifts in the bacterial community composition and structure. Bacterial community diversity patterns induced by clear-cutting were consistent with the intermediate disturbance hypothesis. Dynamics of bacterial communities was mostly driven by soil properties, which collectively explained more than 70% of the variation in bacterial community composition. Community assembly data revealed that clear-cutting promoted the importance of the deterministic processes in shaping bacterial communities, coinciding with the resultant low resource environments. But assembly processes in the secondary forest returned a similar level compared to the intact primary forest. These findings suggest that bacterial community dynamics may be predictable during the natural recovery process.

Fever is an adaptive host response coordinated by the central nervous system (CNS) during systemic immune challenge. Recent research shed light on the mechanism of fever generation, particularly the underlying neural pathways. In this review, we first briefly summarize current views on the mechanism of sensing microbial infection by the nervous system, and the roles of prostaglandin E2 (PGE2) and its receptors in fever; then we focus on the neural circuits underlying fever generation, particularly their relationship with the distribution of PGE2 receptors within the CNS. At the end, an overall neurochemical model of fever generation is presented, pointing to the direction for future studies.

Nanometer titanium dioxide immobilized on silica gel (immobilized nanometer-scale TiO 2 particles) was prepared by a sol-gel method and characterized by X-ray diffraction and scanning electron microscopy. The adsorptive behavior of Cr(III) and Cr(VI) on immobilized nanometer TiO 2 was assessed. Cr(III) was selectively sorbed on immobilized nanometer TiO 2 in the pH range of 7-9, while Cr(VI) was found to remain in solution. A sensitive and selective method has been developed for the speciation of chromium in water samples using an immobilized nanometer TiO 2 microcolumn and inductively coupled plasma atomic emission spectrometry. Under optimized conditions (pH 7.0, flow rate 2.0 mL/min), Cr(III) was retained on the column, then eluted with 0.5 mol/L HNO 3 and determined by ICP-AES. Total chromium was determined after the reduction of Cr(VI) to Cr(III) by ascorbic acid. The adsorption capacity of immobilized nanometer TiO 2 for Cr(III) was found to be 7.04 mg/g. The detection limit for Cr(III) was 0.22 ng/mL and the RSD was 3.5% (n = 11, c= 100 ng/ mL) with an enrichment factor of 50. The proposed method has been applied to the speciation of chromium in water samples with satisfactory results.

The adsorption behavior of multiwalled carbon nanotubes (MWNTs) toward copper has been investigated systemically, and a new method has been developed for the determination of trace copper in water samples based on preconcentration with a microcolumn packed with MWNTs prior to its determination by flame atomic absorption spectrometry. The optimum experimental parameters for preconcentration of copper, such as pH of the sample, sample flow rate and volume, elution solution and interfering ions, have been investigated. Copper can be quantitatively retained by MWNTs in the pH range 5-8, and then eluted completely with 0.5 M HNO 3 . The detection limit of this method for Cu was 0.42 ng/mL, and the RSD was 3.5% at the 10 ng/mL Cu level. The method was validated using a certified reference material, and has been successfully applied for the determination of trace copper in water samples.

To study the prevalence of mild cognitive impairment (MCI) in the urban and the rural areas in Chengdu, Southwest China.Residents aged 55 or over were selected by stratified random cluster sampling from 19 districts, cities, and counties of Chengdu area in Sichuan province. A two-stage survey was carried out. In the first stage, CMMSE, CES-D were used as screening instruments. In the second stage, Diagnostic questionnaires of dementia and CDR were used as diagnostic instruments. The diagnostic criteria of mild cognitive impairment adopted from Petersen's were: (1) memory complaint; (2) normal activities of daily living; (3) normal general cognitive function; (4) memory impairment incompatible with age; (5) not demented; (6) CDR = 0.5 and (7) exclusion of the reversible cognitive impairment caused by other factors (i.e. depression).Three thousand, nine hundred and ten subjects were examined. The prevalence rates of MCI was 2.4%. The MCI prevalence rates in the urban and the rural areas were 1.5%, 2.5% respectively, without significant difference. The MCI prevalence in males and females were 1.8%, 2.9% respectively. Prevalence rate in female was higher than in males with significant difference. Prevalence of illiteracy (4.0%) was the highest among different educational levels. The accumulated prevalence increased with age.The prevalence of MCI (2.4%) was slightly higher than the prevalence of AD (2.05%) in the same areas of Chengdu. MCI seemed to be a high risk factor for AD which should to be followed up. Early intervention in MCI might be helpful in the prevention of AD.

The molecular weights of the native polysaccharides of Erwinia chrysanthemi strains range from 1.8 to 7.1 x 10(6) and their hydrodynamic properties are those of polydisperse, polyanionic biopolymers with pseudoplastic, non-thixotropic flow characteristics in aqueous solutions. The effect on the hydrodynamic properties of the polysaccharides by adding carboxyl groups to increase the charge density is studied, with particular reference to their molecular weight (MW), viscosity and conformation. In general, it is found that periodate oxidation of the extracellular polysaccharides of E. chrysanthemi strains, Ech9Sm6 and Ech6S+, introduces little change in the hydrodynamic properties of the resulting polyaldehydes. However, bromine oxidation at neutral pH of the polyaldehydes results in polycarboxylate biopolymers that show significant reduction in MW and viscosity, but they are still characteristic polyanions.

Extracellular polysaccharides (EPSs) produced by an Erwinia sp associated with a fungal canker disease of Eucalyptus were fractionated into one polysaccharide that was identified with that produced by Erwinia chrysanthemi strains SR260, Ech1, and Ech9, and the other distinctively different from any other EPS produced by E. chrysanthemi strains so far studied. Their structures were determined using a combination of chemical and physical techniques including methylation analysis, low pressure gel-filtration, and anion-exchange chromatographies, high-pH anion-exchange chromatography, mass spectrometry and 1D and 2D 1H NMR spectroscopy. The new polysaccharide, identified as EPS Teranera, has the following structure: [structure: see text] The molecular weights of the polysaccharides range from 3.2-6.2 x 10(5) and their hydrodynamic properties are those of polydisperse, polyanionic biopolymers with pseudoplastic, non-thixotropic flow characteristics in aqueous solutions.

The possibility was investigated by using 1-phenyl-3-methyl-4-benzoyl-5-pyrazolone (PMBP) as the chelating reagent for separation and preconcentration of manganese(II) by cloud point extraction (CPE) and subsequent determination by flame atomic absorption spectrometry (FAAS). The effects of experimental conditions such as pH, concentration of chelating agent and surfactant, equilibration temperature and time on cloud point extraction were studied. Under the optimum conditions, preconcentration of 10 ml of sample solution permitted the detection of 1.45 ng mL(-1) of manganese with an enrichment factor of 20. The proposed method was applied to the determination of trace manganese in water samples with satisfactory results.

Coinfection with human immunodeficiency virus-1 (HIV-1) and hepatitis C virus (HCV) accelerates hepatitis C disease progression; however, the mechanism underlying this effect is unknown. Here, we investigated the role of HIV-1 in HCV gene expression and the mechanism involved in this regulation. We discovered that HIV-1 Rev protein activates HCV gene expression. We further revealed that Rev binds to the internal loop of the HCV 5′-untranslated region (5′-UTR) to stimulate HCV IRES-mediated translation.

Coastal wetlands are considered the most biologically diverse of all ecosystems. Understanding their structures and functions is important for coastal environmental management and development. Airborne LiDAR (Light Detection and Ranging) has emerged as an effective tool for creating high-resolution digital surface models (DSM, highest elevation points) and digital terrain models (DTM, ground only points), which are vital geographic information sources for various applications in coastal areas, and investigating spatial patterns of vegetation in areas that are difficult to access. This paper investigates LiDAR’s capability for mapping marine wetlands, extracting vegetation and channel networks, and identifying intertidal zones. The Yellow River Delta, China, was selected as a study site to conduct experiments. With only a 4.5-h flight, an area of more than 670 km2 was surveyed with great detail. High-resolution DSMs and DTMs were generated, the vegetation coverage and heights were extracted using methods based on height and multi-return and the results were compared, and the water and tidal channels, which reflect the complete water transport system in the area, were mapped and measured. By combining LiDAR data and local tidal observations, the intertidal zone, which is a significant part of coastal wetlands, is clearly identified.