黑龙江五大连池的生态价值分析

黑龙江五大连池处于大小兴安岭和松嫩平原的交错地带,在过去210万年间经历了7次大规模的火山喷发,是中国保存最为完好的内陆火山遗迹,2010年被我国政府遴选为世界自然遗产提名地.为了科学、准确地阐述五大连池生态方面的突出普遍价值,本文在<实施世界遗产公约操作指南>的框架下,整合野外调查数据和文献资料,在与其他相关世界遗产地充分比较的基础上,较为全面地分析了五大连池的生态价值.五大连池植物地理特征交错,区系来源广泛;物种组成相对丰富;发育在熔岩台地上的矮曲林反映了植物的特殊适应过程:特有成因形成了陆生和水生两个完整的植被演替序列;陆生植被演替同时存在普通演替和斑块动态演替两种模式,在熔岩地貌上斑块动态演替模式更为随机而高效.上述生态特征充分展示了五大连池正在进行的生物生态过程,体现了五大连池独特的生态价值,为后续有效保护和深入科学研究提供了支撑.     

胡瓜钝绥螨对日光大棚茄子上烟粉虱的控制作用

为了评价胡瓜钝绥螨在我国日光大棚中对茄子上烟粉虱虱的控制作用。笔者研究了在24～34℃下胡瓜钝绥螨以烟粉为猎物时的发育历期,并在我国山东省寿光市的蔬菜基地上开展了利用胡瓜钝绥螨控制日光大棚茄子上烟粉虱的研究与应用。结果表明:胡瓜钝绥螨能够取食烟粉虱的卵、成虫、若虫及伪蛹;利用胡瓜钝绥螨能有效地控制烟粉虱成虫、卵、若虫种群数量的增长。根据胡瓜钝绥螨和烟粉虱的生物学特性,结合大棚茄子栽培过程中的环境条件,笔者提出了在日光大棚中应用胡瓜钝绥螨控制茄子上烟粉虱的策略:(1)在茄子的整个生长季节(250d)中需释放胡瓜钝绥螨4～6次,苗期每次每株释放5～10头,结果期每次每株释放20～40头;(2)释放胡瓜钝绥螨的生防区比常规化防区减少农药使用18次;(3)安装防虫网、适时释放胡瓜钝绥螨是生防成功之关键,生防区配合使用黄板效果更好。     

派伦螨属四已知种雄螨及若螨描述(蜱螨亚纲:中气门目:派盾螨科)

本文描述拟双毛派伦螨Parholaspulus paradichaetes Petrova,1967雄螨及前若螨,阿氏派伦螨 P.alstoni Evans,1956后若螨及前若螨,微小派伦螨 P.minutus Petrova,1967和东方派伦螨 P.orientalis Petrova,1967后若螨.     

steve bAccumulation of nerve growth factor and its receptors in the uterus and dorsal root ganglia in a mouse model of adenomyosis

Background  

Adenomyosis is a common gynecological disease, which is accompanied by a series of immunological and neuroendocrinological changes. Nerve growth factor (NGF) plays a critical role in producing pain, neural plasticity, immunocyte aggregation and release of inflammatory factors. This study aimed to investigate the expression of NGF and its two receptors in uteri and dorsal root ganglia (DRG) in an adenomyosis mouse model, as well as their relationship with the severity of adenomyosis.     

Oncogenic RAS regulates BRIP1 expression to induce dissociation of BRCA1 from chromatin, inhibit DNA repair, and promote senescence

Here, we report a cell-intrinsic mechanism by which oncogenic RAS promotes senescence while predisposing cells to senescence bypass by allowing for secondary hits. We show that oncogenic RAS inactivates the BRCA1 DNA repair complex by dissociating BRCA1 from chromatin. This event precedes senescence-associated cell cycle exit and coincides with the accumulation of DNA damage. Downregulation of BRIP1, a physiological partner of BRCA1 in the DNA repair pathway, triggers BRCA1 chromatin dissociation. Conversely, ectopic BRIP1 rescues BRCA1 chromatin dissociation and suppresses RAS-induced senescence and the DNA damage response. Significantly, cells undergoing senescence do not exhibit a BRCA1-dependent DNA repair response when exposed to DNA damage. Overall, our study provides a molecular basis by which oncogenic RAS promotes senescence. Because DNA damage has the potential to produce additional "hits" that promote senescence bypass, our findings may also suggest one way a small minority of cells might bypass senescence and contribute to cancer development.     

Rheb1 is required for mTORC1 and myelination in postnatal brain development

mTor kinase is involved in cell growth, proliferation, and differentiation. The roles of mTor activators, Rheb1 and Rheb2, have not been established in?vivo. Here, we report that Rheb1, but not Rheb2, is critical for embryonic survival and mTORC1 signaling. Embryonic deletion of Rheb1 in neural progenitor cells?abolishes mTORC1 signaling in developing brain and increases mTORC2 signaling. Remarkably, embryonic and early postnatal brain development appears grossly normal in these Rheb1f/f,Nes-cre mice with the notable exception of deficits of myelination. Conditional expression of Rheb1 transgene in neural progenitors increases mTORC1 activity and promotes myelination in the brain. In addition the Rheb1 transgene rescues mTORC1 signaling and hypomyelination in the Rheb1f/f,Nes-cre mice. Our study demonstrates that Rheb1 is essential for mTORC1 signaling and myelination in the brain, and suggests that mTORC1 signaling plays a role in selective cellular adaptations, rather than general cellular viability.     

Electrochemiluminescence of palmatine being oxidized by electrogenerated hydroxyl radical and its analytical application

A strong electrochemiluminescence (ECL) of palmatine in NaOH medium was observed at a vaseline‐impregnated graphite anode. The ECL production could be described as follows: hydroxyl radical (OH^?) was generated via the oxidation of hydroxyl group (OH^‐) in NaOH medium, and the formed OH^? subsequently oxidized palmatine base converted from palmatine in NaOH medium to the excited state oxypalmatine (oxypalmatine*). As the oxypalmatine* went back to its ground state, a stronger chemiluminescence was produced. Based on the ECL of palmatine, an ECL method for the determination of palmatine was proposed. An ECL signal of palmatine in NaOH solution was obtained by applying direct current of 15 mA to the vaseline‐impregnated graphite anode. The ECL intensity was rectilinear with palmatine concentration in the range of 8.0 × 10^?7 to 2.0 × 10^?5 mol l^?1 and the limit of detection (signal‐to‐noise = 3) was 3 × 10^?7 mol l^?1. The proposed method was applied to the determination of palmatine in pharmaceutical preparations. Copyright © 2010 John Wiley & Sons, Ltd.     

Norfloxacin Sorption to Different Fractions in Sediments from Typical Water Systems in China

Sorption isotherms of Norfloxacin (NOF) to different fractions from six typical sediments in China were determined to compare the NOF sorption behavior and contribution of different fractions to total sorption. All sorption isotherms were nonlinear and fitted well with the Freundlich model. Sorption coefficients (K _f) by original sediments changed in larger magnitude, from 114 (mg/g)/(mg/L)ⁿ to 5271 (mg/g)/(mg/L)ⁿ, and black carbon with more aromatic carbon has more sorption capacity and nonlinearity. The sorption capacity K _f values were found to significantly correlate with SSA (specific surface area), OC (organic carbon), BC (black carbon), and TON (total organic nitrogen) (p < 0.05), but had no obvious relation with pH, CEC (cation exchange capacity), TOC/TON, and BC/TOC. The DOC removed, NaOH extracted, and 375°C heated fractions showed more nonlinear sorption than the original sediments, suggesting more heterogeneous sorption sites in these fractions. Among different sediment fractions, the 375°C heating fractions were responsible for >50% of the total NOF sorption over the whole concentration range. The contribution of DOC removed fractions to the total sorption was the highest at higher NOF concentration.     

MnSOD expression inhibited by electromagnetic pulse radiation in the rat testis

Male Sprague Dawley rats were exposed to EMP irradiation of 100?kV/m peak-to-peak e-field intensity and different numbers of pulses. Rat sperm samples were prepared for analysis of sperm qualities; Testes were assessed by transmission electron microscopy and serum hormone concentrations were examined by radioimmunoassay; Enzymatic activities of Total-superoxide dismutase(T-SOD) and manganese-superoxide dismutase (MnSOD), the mRNA levels of MnSOD and cuprozinc-superoxide dismutase (CuZnSOD), and the density of malondialdehyde (MDA) were also determined. EMP irradiation did not affect spermatozoon morphology, micronucleus formation rate, sperm number or viability, but the acrosin reaction rate decreased at 24?h and 48?h and recovered by 72?h after irradiation as compared to the controls. The ultrastructure of rat testis displayed more serious damage at 24?h than at other time points (6?h, 12?h, 48?h). Serum levels of luteotrophic hormone (LH) and testosterone (T) were elevated in irradiated rats as compared to controls. After irradiation, enzymatic activities of T-SOD and MnSOD were reduced by 24?h, consistent with the changes observed in MnSOD mRNA expression; MDA content increased at 6?h in turn. These studies have quantified the morphological damage and dysfunction in the rat reproductive system induced by EMP. The mechanism of EMP induced damage may be associated with the inhibition of MnSOD expression.     

Development of casparian strip in rice cultivars

The development of Casparian strips (CSs) on the endo- and exodermis and their chemical components in roots of three cultivars of rice (Oryza sativa) with different salt tolerance were compared using histochemistry and Fourier transform infrared (FTIR) spectroscopy. The development and deposition of suberin lamellae of CSs on the endo- and exodermis in the salt-tolerant cultivar Liaohan 109 was earlier than in the moderately tolerant cultivar Tianfeng 202 and the sensitive cultivar Nipponbare. The detection of chemical components indicated major contributions to the structure of the outer part from aliphatic suberin, lignin and cell wall proteins and carbohydrates to the rhizodermis, exodermis, sclerenchyma and one layer of cortical cells in series (OPR) and the endodermal Casparian strip. Moreover, the amounts of these major chemical components in the outer part of the Liaohan 109 root were higher than in Tianfeng 202 and Nipponbare, but there was no distinct difference in endodermal CSs among the three rice cultivars. The results suggest that the exodermis of the salt-tolerant cultivar Liaohan 109 functions as a barrier for resisting salt stress.Key words: casparian strip, chemical components, development, rice, rootPlant roots are in direct contact with the soil environment and thus particularly affected by unfavorable conditions. To withstand the surrounding environment, roots have developed anatomical and physiological adaptations. The development of Casparian strips (CSs) in the root endo- and exodermis is one such strategy.^1–3 In roots of most species, the sequence of development of the endo- and exodermis is roughly the same and involves two consecutive developmental stages: (1) formation of CSs in radial and transverse walls impregnating the primary cell wall pores with lipophilic and aromatic substances and (2) deposition of suberin lamellae to the inner surface of anticlinal and tangential cell walls.^4–6A major function of the CS is to block the non-selective apoplastic bypass flow of water and ions into the stele.³ Therefore, the structure,^7–9 chemical nature,^10–12 and physiological function^13,14 of endo- and exdodermal CSs in roots have been the focus of many investigations. Although oxygen loss, drought and salinity can influence the development and chemical nature of CSs in different rice cultivars,^15–19 few investigations have considered the development and formation of endo- and exdodermal CSs in the roots of rice cultivars with different salt tolerance under normal growing conditions.In the present paper, light microscopy and Fourier transform infrared (FTIR) spectroscopy were used to examine the cytochemistry and root anatomy of isolated CSs. The aim was to compare anatomical development and chemical characteristics of the endoand exdodermal CSs of three rice (Oryza sativa L.) cultivars having different salt tolerance in north China: the salt-tolerant Liaohan 109 and two widely grown cultivars, Tianfeng 202 and Nipponbare.