论植物赋所承载的文化意蕴

植物赋所写对象往往具有丰富的文化意蕴,与古代饮馔、医药、哲学、宗教、政治、民俗、审美好尚等有着十分密切的关系。而这种文化意义的生成从总体上来说离不开古人"天人合一"的哲学认知、神话传说与宗教信仰的影响以及历史人物与事件的穿插。同时,植物赋若要有效、艺术地传达物象隐含的文化意蕴,则与赋作的体物方法及赋家的体验方式有着深切的关联。

Experimental study on the properties of CMTs-incorporated geopolymers prepared at low temperatures

Considering that copper mine tailings(CMTs)are commonly mixed with ordinary Portland cement,fly ash(FA),and kaolin to produce geopolymers,to make full use of CMTs,the properties of geopolymers manufactured under different material mass ratios and curing methods(standard curing,water bath curing,and 60℃curing)are evaluated with significantly increased dosage of CMTs.Porosity and unconfined compressive strength tests,X-ray diffraction,field emission scanning electron microscopy,and energy dispersive spectroscopy are used to determine the physical and mechanical properties,microstructure,and mineral composition of geopolymers.Finally,costs and CO 2 emissions of specimens with different material mass ratios during the preparation processes are compared.The results show that during the geopolymerization of low-calcium materials,various geopolymer gels,including calcium silicate,calcium silicoaluminate,and mainly sodium silicoaluminate gels,coexist.The solid waste,cost,and carbon dioxide emission reductions can reach 100%,166.3 yuan/t,and 73.3 kg/t,respectively.Under a curing condition of 60℃,the sample with a CMTs mass fraction of 70%and an FA mass fraction of 30%meets the requirements of porosity,compressive strength.The resource utilization of CMT and FA is realized in a more economical way.

Self-adapting extraction of matrix mineral bulk modulus and verification of fluid substitution

Gassmann＇s equations are commonly used for predicting seismic wave velocity in rock physics research.However the input matrix mineral bulk modulus parameters are not accurate,which greatly influences the prediction reliability.In this paper,combining the Russell fluid factor with the Gassman-Biot-Geertsma equation and introducing the dry-rock Poisson＇s ratio,we propose an effective matrix mineral bulk modulus extraction method.This method can adaptively invert the equivalent matrix mineral bulk modulus to apply the Gassmann equation to fluid substitution of complex carbonate reservoirs and increase the fluid prediction reliability.The verification of the actual material fluid substitution also shows that this method is reliable,efficient,and adaptable.

Agroinoculation as a Simple Way to Deliver a Tobacco Mosaic Virus- Based Expression Vector

烟草花叶病毒(TMV)表达载体30B是一个目前广泛应用的植物病毒表达载体,但用其生产外源蛋白时,必须先将它体外转录成RNA,才能被用来接种宿主植物。由于RNA体外转录费用昂贵、操作复杂,因此限制了30B表达载体的进一步应用。针对这一不足,我们用农杆菌接种法(agroinoculation)接种该病毒载体,即将30B cDNA置于花椰菜花叶病毒(CaMV)的35S启动子和终止子之间,再将整个表达框架插入到农杆菌T-DNA的左边界和右边界之内,构建成质粒p35S-30B,将转入该质粒的农杆菌注射到植物的叶片中,30B cDNA随T-DNA进入植物细胞后,被转录成可自我复制的RNA形式,进而发生系统侵染。为了检测此接种方式的可行性,绿色荧光蛋白(GFP)报告基因被克隆到p35S-30B中,构建成p35S-30B∶∶GFP,用含有该质粒的农杆菌进行注射操作。证实该病毒载体可通过简便的农杆菌接种法侵染Nicotiana benthamiana,在被接种植物的系统叶中,GFP的表达量可占植物总可溶蛋白的5.2％。

Enantioselective analytical methods in chiral drug metabolism

The chiral nature of biological systems enables their stereoselective interaction with chiral compounds. It has been well documented that the enantiomers ofa chiral drug may show differences in drug disposition especially in metabolic behavior. As a result, it is of vital importance to separate the enantiomers of a chiral drug in metabolic studies. This paper discusses enantioselective methods （include high-performance liquid chromatography, gas chromatography, capillary electrophoresis and high-performance liquid chromatography-mass spectrometry） that applied in chiral drug metabolism, using most recent examples where possible.

Cryopreservation of Gametophytes of Laminaria japonica (Phaeophyta) Using Encapsulation-Dehydration with Two-Step Cooling Method

Gametophytes of Laminaria japonica were cryopreserved in liquid nitrogen using encapsulation-dehydration with two-step cooling method. Gametophytes cultured at 10℃ and under continuous irradiance of 30 μmol m^-2 s^-1 for 3 weeks were encapsulated in calcium alginate beads. The beads were dehydrated in 0.4 molLl sucrose prepared with seawater for 6 h, desiccated in an incubator set at 10℃ and 70% relative humidity for 4 h, pre-frozen at either -40℃ or -60℃ for 30 min, and stored in liquid nitrogen for 〉24 h. As high as 43% of survival rate was observed when gametophytes were thawed by placing the beads in 40℃ seawater and re-hydrated in 0.05 molL^-1 citrate sodium prepared using 30‰ NaCl 7 d later. More cells of male gametophytes survived the whole procedure in comparison with female gametophytes. The cells of gametophytes surviving the preservation were able to grow asexually and produce morphologically normal sporophytes.

Troglitazone, a peroxisome proliferator-activated receptor γ ligand, induces growth inhibition and apoptosis of HepG2 human liver cancer cells

AIM: To examine the effect of troglitazone, a peroxisome proliferator-activated receptor γ (PPARγ) ligand, on the proliferation and apoptosis of human liver cancer cells. METHODS: Liver cancer cell line HepG2 was cultured and treated with troglitazone. Cell proliferation was detected by 3-(4-,5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide (MTT) assay; apoptosis was detected by flow cytometry and terminal deoxynucleotidyl transferase- mediated nick end labeling of DNA fragmentation sites (TUNEL) assay; and apoptosis-related protein was detected by immunocytochemistry and Western blotting. RESULTS: Troglitazone inhibited growth and induced apoptosis of HepG2 cells in a dose-dependent manner, and induced activation of caspase-3 expression. Troglitazone not only drove apoptosis-inhibiting factor survivin to translocate incompletely from the nucleus to the cytoplasm, but also inhibited expression of survivin, while it did not affect expression of apoptosis-promoting factor Bax. CONCLUSION: PPARγ ligands inhibit growth and induce apoptosis of liver cancer cells, and may have applications for the prevention and treatment of liver cancer.

Kinetics of the leaching of TiO_2 from Ti-bearing blast furnace slag

Ti-bearing blast furnace slag is a valuable secondary resource containing about 24 percent of TiO2.In this paper a process of leaching Ti-bearing blast furnace slag with sulfuric acid to recover TiO2,and the kinetics of that reaction,are described.Under laboratory conditions the rate is controlled by a chemical reaction.The leaching reaction is in accord with a shrinking unre- acted-core model.The apparent reaction order of the leaching reaction was 1.222 and the apparent activation energy was 87.01 kJ/mol.The model fits the observed data well until 90%of the TiO2 has be leached from the particles.The model disagrees with observations during later periods of the reaction because the solution becomes supersaturated with Ti ions,which precipitate as H2TiO4.The assumptions of constant reactant concentration and that there is no effect from the product layer on diffusion,also cause the model to deviate from the actual values.

Modeling of photolithography process in semiconductor wafer fabrication systems using extended hybrid Petri nets

To describe a semiconductor wafer fabrication flow availably, a new modeling method of extended hybrid Petri nets （EHPNs） was proposed. To model the discrete part and continuous part of a complex photolithography process, hybrid Petri nets （HPNs） were introduced. To cope with the complexity of a photolithography process, object-oriented methods such as encapsulation and classifications were integrated with HPN models. EHPN definitions were presented on the basis of HPN models and object-oriented methods. Object-oriented hybrid Petri subnet models were developed for each typical physical object and an EHPN modeling procedure steps were structured. To demonstrate the feasibility and validity of the proposed modeling method, a real wafer photolithography case was used to illustrate the modeling procedure. dynamic modeling of a complex photolithography process effectively The modeling results indicate that the EHPNs can deal with the dynamic modeling of a complex photolithography process effectively.

Simulation of Solid Suspension in a Stirred Tank Using CFD-DEM Coupled Approach＊

Computational fluid dynamics-discrete element method(CFD-DEM) coupled approach was employed to simulate the solid suspension behavior in a Rushton stirred tank with consideration of transitional and rotational motions of millions of particles with complex interactions with liquid and the rotating impeller. The simulations were satisfactorily validated with experimental data in literature in terms of measured particle velocities in the tank.Influences of operating conditions and physical properties of particles(i.e., particle diameter and density) on the two-phase flow field in the stirred tank involving particle distribution, particle velocity and vortex were studied.The wide distribution of particle angular velocity ranging from 0 to 105r·min 1is revealed. The Magnus force is comparable to the drag force during the particle movement in the tank. The strong particle rotation will generate extra shear force on the particles so that the particle morphology may be affected, especially in the bio-/polymer-product related processes. It can be concluded that the CFD-DEM coupled approach provides a theoretical way to understand the physics of particle movement in micro- to macro-scales in the solid suspension of a stirred tank.

Solving the AKNS Hierarchy by Its Bilinear Form: Generalized Double Wronskian Solutions

Through the Wronskian technique, a simple and direct proof is presented that the AKNS hierarchy in the bilinear form has generalized double Wronskian solutions. Moreover, by using a unified way, soliton solutions, rational solutions, Matveev solutions and complexitons in double Wronskian form for it are constructed.

Role of peroxisome proliferators-activated receptors in the pathogenesis and treatment of nonalcoholic fatty liver disease

Nonalcoholic fatty liver disease （NAFLD） is highly prevalent and can result in nonalcoholic steatohepatitis （NASH） and progressive liver disease including cirrhosis and hepatocellular carcinoma. A growing body of literature implicates the peroxisome proliferators- activated receptors （PPARs） in the pathogenesis and treatment of NAFLD. These nuclear hormone receptors impact on hepatic triglyceride accumulation and insulin resistance. The aim of this review is to describe the data linking PPARα and PPART to NAFLD/NASH and to discuss the use of PPAR ligands for the treatment of NASH.

Telomerase activity: An attractive target for cancer therapeutics

Telomeres are non-coding tandem repeats of 1000-2000 TTAGGG nucleotide DNA sequences on the 3’ termini of human chromosomes where they serve as protective “caps” from degradation and loss of genes. The “cap” at the end of chromosome required to protect its integ-rity is a 150-200 nucleotide-long single stranded G-rich 3’ overhang that forms two higher order structures, a T-loop with Sheltering complex, or a G-quadruplex com-plex. Telomerase is a human ribonucleoprotein reverse transcriptase that continually added single stranded TTAGGG DNA sequences onto the single strand 3’ of telomere in the 5’ to 3’ direction. Telomerase activity is detected in male germ line cells, proliferative cells of renewal tissues, some adult pluripotent stem cells, embryonic cells, but in most somatic cells is not de-tected. Re-expression or up-regulation of telomerase in tumours cells is considered as a critical step in cell tumorigenesis and telomerase is widely considered as a tumour marker and a target for anticancer drugs. Dif-ferent approaches have been used in anticancer thera-peutics targeting telomerase. Telomerase inhibitors can block directly Human TElomerase Reverse Transcrip-tase （hTERT） or Human TElomerase RNA telomerase subunits activity, or G-quadruplex and Sheltering complex components, shortening telomeres and inhibiting cell proliferation. Telomerase can become an immune target and GV1001, Vx-001, I540 are the most wide-spread vaccines used with encouraging results. Another method is to use hTERT promoter to drive suicide gene expression or to control a lytic virus replication. Recently telomerase activity was used to activate pro-drugs such as Acycloguanosyl 5’-thymidyltriphosphate, a synthetic ACV-derived molecule when it is activated by telomer-ase it does not require any virus or host active immune response to induce suicide gene therapy. Advantage of all these therapies is that target only neoplastic cells without any effects in normal cells, avoiding toxicity and adverse effects of the current chemotherapy. However, as not all the approaches are equally effcient, further studies will be necessary.

Treating ballast water with hydroxyl radical on introduced organisms

With physical method of micro-gap gas discharge, a large amount of hydroxyl radical can be produced in 20t/h pilot-scale system using the ionization of 02 and H2O. In this paper, the effect of biochemistry of hydroxyl radicals on introduced organisms in ballast water was experimentally investigated. The results indicate that the contents of chlorophyl-a, chlorophyl-b, chlorophyl-c and carotenoid are decreased by 35%-4% within 8.0s and further to the lowest limit of test 5 minutes. In addition, the main reasons of cell death are the lipid peroxidation, the strong destruction to the monose, amylose, protein, DNA and RNA of cell, and damage in CAT, POD and SOD of antioxidant enzyme system.

Synthesis and Characterization of New Polyimide Containing Calix[4] arenes in the Polymer Backbone with Transport Ability

New polyimide containing calix [4] arene moieties on the polymer backbone was successfully synthesized in N- methy1 - 2 - pyrrolidone （NMP） by polycondensations of 3, 3＇, 4, 4＇- oxydiphthalic anhydride （ODPA） with the diaminocalix[4]arene monomer using 3,3＇- dimethy1- 4, 4＇- The polyimide prepared is soluble in common solvents, such as NMP, DMAc, DMF and chloroform. The polyimide films obtained have excellent thermal stability and mechanical property. At the same time, the liquid membrane transport of potassium ions by the new polyimide was investigated, which testified that compared to ODPA-DADPM polyimide, the polyimide containing culix[4] arenes has the transport ability to metal ions in regard to bulky, cone-like calix [-4] arene moieties.

Identification of a Putative Tetrasporophyte-Specific Gene in Gracilaria lemaneiformis(Gracilariales,Rhodophyte)

A putative tetrasporophyte-specific gene,designated as SSH466(GenBank accession No. DQ019223) ,was one of the genes identified in this work using suppression subtractive hybridization(SSH) method in Gracilaria lemaneiformis. The full length of the gene was obtained using SMART RACE strategy. Sequence analysis revealed that the gene had 1 019 nucleotides,including an open reading frame of 498 nucleotides encoding 166 amino acid residues,158 nucleotides of 5' untranslated region and 363 nucleotides of 3' non-coding region. Protein motif and secondary structure prediction showed that there existed a transmembrane domain with a unique β-sheet. Thus,SSH466 protein might be a cross-membrane protein. Sequence homology search in the public GenBank databases did not reveal any significant match with SSH466. Virtual Northern blot analysis confirmed that it was a tetrasporophyte-specific gene.

Numerical investigation on flow and heat transfer characteristics of corrugated tubes with non-uniform corrugation in turbulent flow

Based on finite volume method, the pressure drop and heat transfer characteristics of one smooth tube and ten different axisymmetric corrugated tubes, including two with uniform corrugation and eight with non-uniform corrugation, have been studied. A physical model of the corrugated tube was built, then the numerical simulation of the model was carried out and the numerical simulation results were compared with the empirical formula.The results show that: the friction factor decreases with the increase of Reynolds number ranging from 6000 to 57000, the value of which in the corrugated tubes with non-uniform corrugation(tube 03–10) are smaller than those with uniform corrugation(tube 01–02). The geometry parameters of tube(01) have advantages on the heat transfer enhancement in low Reynolds number flow region(from 6000 to 13000) and tube(07–08)have advantages on the heat transfer enhancement in high Reynolds number flow region(from 13000 to 57000). The vortex, existed in each area between two adjacent corrugations called second flow region, is the root of the enhancement on heat transfer in the corrugated tubes. The effectiveness factor decreases with the increasing of Reynolds number and the performances of the corrugated tubes with pitch of 12.5 mm have advantages than these of 10 mm under the same corrugation geometric parameter.

The human leucocyte differentiation antigens (HLDA) workshops: the evolv-ing role of antibodies in research, diagnosis and therapy

The 8^th International Workshop on Human Leucocyte Differentiation Antigens （chaired by HZ and managed by BS） was run over a 4-year period and culminated in a conference in December 2004. Here we review the achievements of the HLDA Workshops and provide links to information on CD molecules and antibodies against them, including the 93 new CDs assigned in the 8^th Workshop. We consider what remains to be achieved （including an estimate of the number of leucocyte surface molecules still to be discovered）, and how the field can best move forward.

Science Letters:Two ancient rounds of polyploidy in rice genome

An ancient genome duplication (PPP1) that predates divergence of the cereals has recently been recognized. We report here another potentially older large-scale duplication (PPP2) event that predates monocot-dicot divergence in the genome of rice (Oryza sativa L.), as inferred from the age distribution of pairs of duplicate genes based on recent genome data for rice. Our results suggest that paleopolyploidy was widespread and played an important role in the evolution of rice.

Understanding the influence of microwave on the relative volatility used in the pyrolysis of Indonesia oil sands

In this paper, pyrolysis of Indonesian oil sands （lOS） was investigated by two different heating methods to develop a better understanding of the microwave-assisted pyrolysis. Thermogravimetric analysis was conducted to study the thermal decomposition behaviors of lOS, showing that 550 ℃ might be the pyrolysis final temperature. A explanation of the heat-mass transfer process was presented to demonstrate the influence of mi- crowave-assisted pyrolysis on the liquid product distribution. The heat-mass transfer model was also useful to explain the increase of liquid product yield and heavy component content at the same heating rate by two differ- ent heating methods. Experiments were carried out using a fixed bed reactor with and without the microwave irradiation. The results showed that liquid product yield was increased during microwave induced pyrolysis, while the formation of gas and solid residue was reduced in comparison with the conventional pyrolysis. Moreover, the liquid product characterization by elemental analysis and GC-MS indicated the significant effect on the liquid chemical composition by microwave irradiation. High polarity substances （ε 〉 10 at 25 ℃）, such as oxy- organics were increased, while relatively low polarity substances （ε 〈 2 at 25℃）, such as aliphatic hydrocarbons were decreased, suggesting that microwave enhanced the relative volatility of high polarity substances. The yield improvement and compositional variations in the liquid product promoted by the microwave-assisted pyrolysis deserve the further exploitation in the future,