中国串珠藻属的4个新记录种

记述了我国串珠藻属的 4个新记录种 ,即马赫拉串珠藻 Batrachospermum mahlacense Kum ano et Bowden-Kerby、可疑串珠藻 B.ambiguum Montagne、诺诺串珠藻 B.nonocense Kum ano et L iao和钏路串珠藻 B.kushiroenseKumano et Ohsaki

山茛菪中4种生物碱含量与海拔关系的研究

山莨菪Anisodus tanguticus (Maxim.) Pascher系茄科植物，俗称樟柳参，藏医音译唐冲那保，山莨菪作为传统的藏药，具有麻醉、解痉、镇痛、镇静、解磷中毒等多种功效。其有效成分主要是托烷类生物碱，如东莨菪碱（scopolamine)、山莨菪碱（anisodamine)、阿托品（atropine)、樟柳碱(anisodine)等。研究4种托烷类生物碱含量随海拔的变化，对控制药用植物原料的质量、开发药用植物资源和生物资源可持续利用等均具有重要意义。为此我们对此进行了研究。

Performance study of two different compensating devices in a custom power park

Simulation study of a custom power park (CPP) is presented. It is assumed that the park contains unbalanced and nonlinear loads in addition to a sensitive load. Two different types of compensators are used separately to protect the sensitive load against unbalance and distortion caused by the other loads. It has been shown that a shunt compensator can regulate the voltage of the CPP bus, whereas the series compensator can only regulate the sensitive load terminal voltage. Additional issues such as the load transfer through a static transfer switch, detection of sag/fault etc. are also discussed. The concepts are validated through PSCAD/EMTDC simulation studies on a sample distribution system.

Probabilistic load flow in AC electrified railways

System analysis within the traction power system is vital to the design and operation of an electrified railway. Loads in traction power systems are often characterised by their mobility, wide range of power variations, regeneration and service dependence. In addition, the feeding systems may take different forms in AC electrified railways. Comprehensive system studies are usually carried out by computer simulation. A number of traction power simulators have been available and they allow calculation of electrical interaction among trains and deterministic solutions of the power network. In the paper, a different approach is presented to enable load-flow analysis on various feeding systems and service demands in AC railways by adopting probabilistic techniques. It is intended to provide a different viewpoint to the load condition. Simulation results are given to verify the probabilistic-load-flow models.

Insulin-like growth factor-i : vitronectin complex-induced changes in gene expression effect breast cell survival and migration

Recent studies have demonstrated that IGF-I associates with VN through IGF-binding proteins (IGFBP) which in turn modulate IGF-stimulated biological functions such as cell proliferation, attachment and migration. Since IGFs play important roles in transformation and progression of breast tumours, we aimed to describe the effects of IGF-I:IGFBP:VN complexes on breast cell function and to dissect mechanisms underlying these responses. In this study we demonstrate that substrate-bound IGF-I:IGFBP:VN complexes are potent stimulators of MCF-7 breast cell survival, which is mediated by a transient activation of ERK/MAPK and sustained activation of PI3-K/AKT pathways. Furthermore, use of pharmacological inhibitors of the MAPK and PI3-K pathways confirms that both pathways are involved in IGF-I:IGFBP:VN complex-mediated increased cell survival. Microarray analysis of cells stimulated to migrate in response to IGF-I:IGFBP:VN complexes identified differential expression of genes with previously reported roles in migration, invasion and survival (Ephrin-B2, Sharp-2, Tissue-factor, Stratifin, PAI-1, IRS-1). These changes were not detected when the IGF-I analogue (\[L24]\[A31]-IGF-I), which fails to bind to the IGF-I receptor, was substituted; confirming the IGF-I-dependent differential expression of genes associated with enhanced cell migration. Taken together, these studies have established that IGF-I:IGFBP:VN complexes enhance breast cell migration and survival, processes central to facilitating metastasis. This study highlights the interdependence of ECM and growth factor interactions in biological functions critical for metastasis and identifies potential novel therapeutic targets directed at preventing breast cancer progression.

Do people gamble with their lives : The relationship between risky driving behaviour and other risky behaviours

General risky behaviour is explored for correlation with risky driving behaviour in light of two theories, self-control and cross-situational consistency. Identification of general risky behaviours associated with risky driving behaviour, and the theory that best predicts the behaviours, will enable better targeting of intervention and education strategies to reduce driving related fatalities and injuries. A correlational study using participants (N=152) drawn from first year university undergraduates and the public surveyed their lifestyle and behaviours. Relationships were found between risky driving behaviours and other risky behaviours such as alcohol consumption, cannabis use and performing unlawful activities. No significant differences were found between genders, with the exception that males were more likely to believe that they were at risk of injury from their employment, χ2 (1, N = 152) = 4.49, p = .03, were more likely to have performed an unlawful offence, χ2 (1, N = 152) = 11.77, p = .001 and were more likely to drink drive, t (55.41) = -3.87, p < .001, mean difference = -0.63, CI 95% (-0.9, -0.37). People engaged in risky driving behaviours were more likely to engage in other risky behaviours. The theories that were explored were unable to accurately predict an association between general risky behaviour and driving without a license or when disqualified. Cross-situational consistency explained 20% (R2adj = .16) of the variance in which people engaged in risky driving with low self-control theory explaining an additional 0.3% variance (R2change = .003), F (8,143) = 6.92, p < .001. Driving while under the influence of alcohol could be predicted by risky behaviours in lifestyle, health, smoking, cannabis use and alcohol consumption, F (8,143) = 6.92, p < .001. The addition of self-control was not significant.

Interleukin-1β stimulates human renal fibroblast proliferation and matrix protein production by means of a transforming growth factor-β-dependent mechanism

One of the hallmarks of progressive renal disease is the development of tubulointerstitial fibrosis. This is frequently preceded by macrophage infiltration, raising the possibility that macrophages relay fibrogenic signals to resident tubulointerstitial cells. The aim of this study was to investigate the potentially fibrogenic role of interleukin-1beta (IL-1beta), a macrophage-derived inflammatory cytokine, on cortical fibroblasts (CFs). Primary cultures of human renal CFs were established and incubated for 24 hours in the presence or absence of IL-1beta. We found that IL-1beta significantly stimulated DNA synthesis (356.7% +/- 39% of control, P <.003), fibronectin secretion (261.8 +/- 11% of control, P <.005), collagen type 1 production, (release of procollagen type 1 C-terminal-peptide, 152.4% +/- 26% of control, P <.005), transforming growth factor-beta (TGF-beta) secretion (211% +/- 37% of control, P <.01), and nitric oxide (NO) production (342.8% +/- 69% of control, P <.002). TGF-beta (1 ng/mL) and the phorbol ester phorbol 12-myristate 13-acetate (PMA, 25 nmol/L) produced fibrogenic effects similar to those of IL-1beta. Neither a NO synthase inhibitor (N(G)-methyl-l-arginine, 1 mmol/L) nor a protein kinase C (PKC) inhibitor (bis-indolylmaleimide 1, 1 micromol/L) altered the enhanced level of fibronectin secretion or DNA synthesis seen in response to IL-1beta treatment. However, addition of a TGF-beta-neutralizing antibody significantly reduced IL-1beta-induced fibronectin secretion (IL-1beta + IgG, 262% +/- 72% vs IL-1beta + alphaTGF-beta 156% +/- 14%, P <.02), collagen type 1 production (IL-1beta + IgG, 176% +/- 28% vs IL-1beta + alphaTGF-beta, 120% +/- 14%, P <.005) and abrogated IL-1beta-induced DNA synthesis (245% +/- 49% vs 105% +/- 21%, P <.005). IL-1beta significantly stimulated CF DNA synthesis and production of fibronectin, collagen type 1, TGFbeta, and NO. The fibrogenic and proliferative action of IL-1beta on CF appears not to involve activation of PKC or production of NO but is at least partly TGFbeta-dependent.

Demonstration of regulatory cross-talk between P fimbriae and type 1 fimbriae in uropathogenic Escherichia coli

The majority of Escherichia coli strains isolated from urinary tract infections have the potential to express multiple fimbriae. Two of the most common fimbrial adhesins are type 1 fimbriae and pyelonephritis-associated pili (Pap). Previous research has shown that induced, plasmid-based expression of a Pap regulator, papB, and its close homologues can prevent inversion of the fim switch controlling the expression of type 1 fimbriae. The aim of the present study was to determine if this cross-regulation occurs when PapB is expressed from its native promoter in the chromosome of E. coli K-12 and clinical isolates. The regulation was examined in three ways: (1) mutated alleles of the pap regulatory region, including papB and papI, that maintain the pap promoter in either the off or the on phase were exchanged into the chromosome of both E. coli K-12 and the clinical isolate E. coli CFT073, and the effect on type 1 fimbrial expression was measured; (2) type 1 fimbrial expression was determined using a novel fimS : : gfp+ reporter system in mutants of the clinical isolate E. coli 536 in which combinations of complete fimbrial clusters had been deleted; (3) type 1 fimbrial expression was determined in a range of clinical isolates and compared with both the number of P clusters and their expression. All three approaches demonstrated that P expression represses type 1 fimbrial expression. Using a number of novel genetic approaches, this work extends the initial finding that PapB inhibits FimB recombination to the impact of this regulation in clinical isolates.

Correlation of structural disorder with the reversible discharge capacity of nickel hydroxide electrode

Hydrothermal treatment of a slurry of badly crystalline (beta(bc)) nickel hydroxide at different temperatures (65-170 degrees C) results in the progressive ordering of the structure by the step-wise elimination of disorders. Interstratification is eliminated at 140 degrees C, while cation vacancies are eliminated at 170 degrees C. A small percentage of stacking faults continue to persist even in `crystalline' samples. Electrochemical investigations show that the crystalline nickel hydroxide has a very low (0.4 e/Ni) reversible charge storage capacity. An incidence of at least 15% stacking faults combined with cation vacancies is essential for nickel hydroxide to perform close to its theoretical (1 e/ Ni) discharge capacity. (c) 2005 The Electrochemical Society.

Raman signatures of pressure induced electronic topological and structural transitions in Bi2Te3

We report Raman signatures of electronic topological transition (ETT) at 3.6 GPa and rhombohedral (alpha-Bi2Te3) to monoclinic (beta-Bi2Te3) structural transition at similar to 8 GPa. At the onset of ETT, a new Raman mode appears near 107 cm(-1) which is dispersionless with pressure. The structural transition at similar to 8 GPa is marked by a change in pressure derivative of A(1g) and E-g mode frequencies as well as by appearance of new modes near 115 cm(-1) and 135 cm(-1). The mode Grilneisen parameters are determined in both the alpha and beta-phases. (C) 2011 Elsevier Ltd. All rights reserved.

Optical, electrical and structural characterization of ZnO:Al thin films prepared by a low cost sol-gel method

ZnO:Al thin films were prepared on glass and silicon substrates by the sol-gel spin coating method. The x-ray diffraction (XRD) results showed that a polycrystalline phase with a hexagonal structure appeared after annealing at 400 degrees C for 1 h. The transmittance increased from 91 to about 93% from pure ZnO films to ZnO film doped with 1 wt% Al and then decreased for 2 wt% Al. The optical band gap energy increased as the doping concentration was increased from 0.5 wt% to 1 wt% Al. The metal oxide semiconductor (MOS) capacitors were fabricated using ZnO films deposited on silicon (100) substrates and electrical properties such as current versus voltage (I-V) and capacitance versus voltage (C-V) characteristics were studied. The electrical resistivity decreased and the leakage current increased with an increase of annealing temperature. The dielectric constant was found to be 3.12 measured at 1 MHz. The dissipation value for the film annealed at 300 degrees C was found to be 3.1 at 5 V. (C) 2011 Elsevier Ltd. All rights reserved.

Predominant expression and cellular distribution of fish Agr2 in renal collecting system

Anterior gradient 2 (Agr2) genes encode secretory proteins, and play significant roles in anterior-posterior patterning and tumor metastasis. Agr2 transcripts were shown to display quite diverse tissue distribution in different species, and little was known about the cellular localization of Agr2 proteins. In this study, we identified an Agr2 homologue from gibe[ carp (Carassius auratus gibelio), and revealed the expression patterns and cellular localization during embryogenesis and in adult tissues. The full-length cDNA of CagAgr2 is 803 nucleotides (nt) with an open reading frame of 510 nt encoding 169 amino acids. The Agr2 C-terminus matches to the class I PDZ-interacting motif, suggesting that it might be a PDZ-binding protein. During embryogenesis, CagAgr2 was found to be transcribed in the mucus-secreting hatching gland from tailbud stage and later in the pharynx region, swim bladder and pronephric duct as revealed by RT-PCR and whole mount in situ hybridization. In the adult fish, its transcription was predominantly confined to the kidney, and lower transcription levels were also found in the intestine, ovary and gills. To further localize the Agr2 protein, the anti-CagAgr2 polyclonal antibody was produced and used for immunofluorescence observation. In agreement with mRNA expression data, the Agr2 protein was localized in the pronephric duct of 3dph larvae. In adult fish, Agr2 protein expression is confined to the renal collecting system with asymmetric distribution along the apical-basolateral axis. The data provided suggestive evidence that fish Agr2 might be involved in differentiation and secretory functions of kidney epithelium. (C) 2009 Elsevier Inc. All rights reserved.

INPLANE X-RAY-SCATTERING OF EPITAXIAL STRUCTURES

A new approach for in-plane X-ray scattering from the cleavages of epitaxial films or superlattices, where the scattering vectors are parallel to the interfaces, is proposed. This method can be employed to determine directly the in-plane X-ray strains and other atomic registry along the interfaces of the epitaxial structures.

利用两种大型海藻制备生物能源的探索研究

生物质燃料乙醇和沼气都属于发展潜力巨大的生物质能源，大力发展生物质燃料乙醇和沼气对解决当今能源危机、环境污染问题和促进我国经济发展具有重要意义。 本文就海带化工废弃物——海带渣糖化技术、浒苔糖化技术及初步酒精发酵技术、海带沼气发酵技术、浒苔沼气发酵技术进行了可行性研究。 1、海带渣总糖含量为52.6%，海带渣总糖中葡萄糖含量占90.9%，另外还有少量的半乳糖、甘露糖和木糖，这说明海带渣是非常优良的能源生物质。 2、海带渣糖化工艺采取稀硫酸预处理后纤维素酶酶解产糖工艺。海带渣最佳稀硫酸预处理条件为预处理温度121℃、硫酸浓度0.6%、预处理时间60 min，此时海带渣纤维素酶解产糖可达187.8 mg/g干藻。 3、优化了预处理海带渣纤维素酶酶解产糖工艺。各因素对海带渣酶解产糖的影响依次为：pH>温度>时间>酶用量，海带渣纤维素酶解产糖的最佳条件为温度45℃、pH5.2、时间48小时、酶用量16 mg/g干藻，此时糖产量为238.9 mg/g干藻。 4、浒苔总糖含量为67.2%，浒苔总糖主要有葡萄糖、木糖、葡萄糖醛酸和鼠李糖组成，其中葡萄糖和木糖可以做为酒精发酵的原料，这两种糖占总糖含量的51%。 5、以鲜浒苔为原料研究了浒苔稀硫酸水解工艺和纤维素酶酶解工艺。发现浒苔酸水解产糖效果明显优于纤维素酶酶解。 6、以干浒苔为原料研究了浒苔酸解工艺。硫酸水解干浒苔产糖能力优于盐酸、磷酸和马来酸，水解时间为60 min、硫酸浓度为1.8%的时候可用于酒精发酵的糖（葡萄糖和木糖）总产量达到最大值为230.5 mg/g干浒苔，占此条件下总还原糖产量的48.6%。同时发现干浒苔比鲜浒苔更易被硫酸水解产糖。 7、初步研究了浒苔酒精发酵工艺。初步工艺中酒精产量较低、测得酒精在发酵液中浓度为0.23%（v/v），后续工作中需要对酒精发酵工艺进行优化。 8、海带与牛粪比例为4:1（w/w）是海带与牛粪联合厌氧消化的最佳比例，此时产气时间最长，达到37天，总产气量最高，达到13600 mL。 9、在海带与牛粪联合厌氧消化中，增加接种量到15 g（干重）时发酵周期为39天，总产气量为14630 mL，TS产气量为152.4 mL/gTS，接种量为21 g（干重）时发酵周期为36天，总产气量为14090 mL，TS产气量为138.1 mL/gTS，可见适当增加接种量可促进产气量的增加。 10、浒苔与牛粪比例为4:2（w/w）是浒苔与牛粪联合厌氧消化的最佳比例，此时产气时间为33天，总产气量最高达到6785 mL。 11、在浒苔与牛粪联合厌氧消化中，增加接种量到7.5 g（干重）时发酵周期为38天，总产气量为7470 mL，TS产气量为155.6 mL/gTS，接种量为10.5 g（干重）时发酵周期也为38天，总产气量为7020 mL，TS产气量为137.6 mL/gTS，可见增加接种量可促进产气量的增加。

Rapid serological diagnosis of Helicobacter pylori:a need for caution and re-evaluation

Screening for Helicobacter pylori in dyspeptic patients may improve selectivity for gastroscopy. Rapid serological tests based on ELISA technique are cheap, readily available and simple to use in the clinical setting. However local evaluation is essential in order to validate these techniques. Fifty-six dyspeptic patients (aged less than 45 yr) had a rapid serological test (Helisal) performed prior to gastroscopy. At gastroscopy H. pylori status was assessed using culture and histology. The Helisal sensitivity was 80 per cent, specificity 82 per cent. Screening patients with the Helisal test would have missed 6 patients with peptic ulcer disease and 2 with oesophagitis. The Helisal test did not perform satisfactorily as a screening test in selection of patients for gastroscopy.