低氧对高原鼠兔肝细胞内质网和心肌肌浆网Ca~(2+)泵的影响

模拟高原低氧条件研究高原鼠兔肝细胞内质网(Endoplasmic reticulum , ER ) 和心肌肌浆网(Sarcoplasmic reticulum , SR) 钙泵功能变化。实验设对照组(海拔2 300 m ) 和两个低氧实验组(模拟海拔5 000m 和7 000m )。24 h 急性低氧时, 海拔5 000 m 组高原鼠兔ER 的Ca2+ 泵活性无变化, 海拔7 000 m 组高原鼠兔ER Ca2+泵活性下降29102%。7 d 亚急性低氧时高原鼠兔SR 的Ca2+泵活性无显著变化。高原鼠兔ER 的Ca2+泵活性在海拔5 000 m 组和7 000 m 组分别升高32.50% 和33.33%。25 d 慢性低氧时高原鼠兔ER , SR 的Ca2+ 泵活性均无显著变化.表明: 急性低氧对Ca2+泵功能有抑制作用, 低氧7 d 后抑制缓解, 至25 d 低氧时趋于恢复。

喀斯特石灰土-灌丛系统主要养分含量分布特征研究---以贵阳花溪杨中石灰土-灌丛系统Ca���Mg、 K 、P为例

本论文通过对贵州贵阳花溪杨中喀斯特山区的植被调查与土壤样品分析, 研究土壤-植被中Ca���Mg、 K、P分布特征、变化规律及其影响因素，并在此基础上尝试Ca���位素的预处理研究，以期为喀斯特地区土壤-植被中Ca���Mg、 K、P（尤其是Ca���的生物地球化学循环研究奠定基础，同时为植被演替、物质循环研究和退耕还林还草的人工恢复提供植物自身的营养依据。本次研究取得如下认识： 1.受石灰岩母岩控制，土壤样品元素含量的特征为：CaO>MgO>K2O> P2O5。同一元素沿海拔变化有一定的相关性，并且相关性随元素的不同存在差异：随海拔高度的增加CaO含量有升高的趋势，而MgO 、K2O、Na2O含量都有所降低。表层土壤中K2O-Na2O含量正相关变化，CaO-K2O含量负相关变化。并且从土壤表层到底层在剖面-1中随深度增加，CaO、MgO、K2O含量升高，而P2O5的含量则有上升的趋势。土壤中元素的上述分布特征主要与石灰岩的风化成土作用过程中不同分化程度土壤Ca���淋失和来自高处的富钙雨水输入有关。 2.喀斯特生态环境富钙的这一特点对喀斯特灌丛植物的种类成分和营养元素含量有很大影响。地貌部位、海拔高度对植物Ca���Mg 、K、P含量也有不同程度的影响。植物Ca���Mg 、K、P含量由高到低依次为：Ca > K > Mg >P。苔藓与其它植物比较， Ca���Mg、 K、P的含量都小于其它三类较高等的植物，这一现象与其自身的生物学特性有关：苔藓植物组织结构简单，不具备发达的输导组织，不具备真正的根系，不利于从土壤等基质中吸收营养。在、灌草、灌木、藤本三类植物营养元素之间Ca –P含量具有负相关变化，Mg –P含量具有正相关变化；在所分析的植物种，P- K含量变化呈正相关，并且植物叶片Ca/K比值随着P含量的增加而显著地以指数形式减小。这是因为植物体内的K和P对于Ca���说起着平衡离子（counter ion）的作用。 3. 生境中基岩裸露和土体浅薄的特点，极大地制约了喀斯特灌丛的发育，喀斯特生境的富含钙的特点对喀斯特灌丛植物的种类成分和元素含量有很大的影响。但是杨中灌丛群落植物Ca���Mg、K、P含量和对应土壤CaO、MgO、K2O和P2O5含量相关性不明显。植物Ca���Mg、K、P元素虽主要来源于土壤，但因其含量受元素地球化学性质、植物种类、土壤元素对植物有效态的含量等因素的制约，而使植物元素含量和土壤元素的含量没有明显的相关性． 4.从Ca���位素的预处理研究来看，离子交换分离法对去除样品中的杂质效果较好。在以后测定过程中，有利于增强离子流稳定性和强度, 提高测量精度和准确度，与沉淀法相比较，此法适宜作为钙同位素样品的前处理方法。 关键词： 喀斯特 石灰土-灌丛系统 Ca���Mg、K、P含量分布 钙同位素 环境地球化学

湖泊沉积物碳氧同位素和介形虫Li/Ca���值与古环境重建

了解过去是认识现在和预测未来的基础。晚全新世是PAGES研究的目标时段之一。寻找和解译最近2000年连续、高分辨率自然记录是古气候研究的热点与难点。本项研究有针对性地选择程海、草海和青海湖开展湖泊沉积物环境记录的精细研究，结合14C、210Pb和137Cs定年，系统探讨了碳酸盐碳氧同位素、纤维素碳氧同位素、有机质碳同位素以及介形虫壳体Li/Ca���值指标的古环境指示意义。 通过研究，本论文取得了如下成果和新的认识： 1. 建立了一套有效的四阶段湖泊沉积物有机质纤维素提取方法（5%NaOH碱洗、5%HCl酸洗、亚氯酸钠和冰醋酸混合溶液漂白以及17.5%NaOH碱洗），红外光谱鉴定提取物为纯的α-纤维素，表明该实验方法是可行的，为今后广泛开展湖泊沉积物纤维素稳定同位素研究打下了坚实基础。 2. 多指标综合辨识了程海和草海沉积物碳酸盐主要是自生碳酸盐。程海和草海沉积物有机质C/N比值结合有机质碳同位素结果表明两湖的有机质分别源于水生植物藻类和大型水草。程海和草海沉积物碳酸盐含量主要反映了湖区温度的变化。 3. 程海、草海沉积物碳酸盐与青海湖沉积物介形虫壳体氧同位素组成均反映了湖区降水/蒸发比。降水/蒸发比大的湿润期，碳酸盐δ18O值小；降水/蒸发比小的干旱期，碳酸盐δ18O值大。程海沉积物碳酸盐碳同位素组成影响因素复杂，除了受大气与湖水之间的CO2交换影响外，还受水生植物光合/吸收作用的影响；草海沉积物碳酸盐碳同位素组成更大的变化范围，反映了湖区水生植物光合/吸收作用的影响，其异常的正值可能指示了湖区细菌参与有机质碳同位素分馏过程。 4. 利用草海沉积物有机质纤维素氧同位素定量恢复了湖水氧同位素组成变化。在此基础上，结合碳酸盐氧同位素组成初步恢复了草海地区过去500年来温度变化历史：草海地区在过去500年明显存在四个冷期，包括1550－1610年，1670－1730年，1770－1870年和1890－1920年冷期，其中前三个发生在传统意义上的现代小冰期时段。与其它记录研究结果的一致性表明纤维素氧同位素结合碳酸盐氧同位素是恢复古温度变化的最有效途径之一，同时也为现代小冰期在中国西南地区的存在提供了湖泊沉积学方面的证据。 5. 不同类型水生植物湖泊，湖泊沉积物有机质δ13C值对湖泊初级生产力变化的响应过程不同。大型水草为主的湖泊（草海），其沉积物有机质δ13C值随湖泊生产力的增大呈现增加的变化趋势；藻类为主的湖泊（程海），其沉积物有机质δ13C随湖泊生产力的增大呈现减小的变化趋势，藻类易降解是导致δ13C值随湖泊生产力的增大呈现减小变化趋势的主要原因。 6. 程海沉积物碳酸盐和有机质碳同位素组成的正相关变化以及草海沉积物碳酸盐和有机质碳同位素组成的负相关变化.表明湖泊生产力变化并不是导致碳酸盐和有机质碳同位素正相关变化的主要原因，湖泊水生植物类型以及湖泊大小均起着重要作用。湖泊沉积物碳酸盐与有机质之间的碳同位素分馏（△δ13C）是一种有效的湖泊生产力指示剂，即使是在有微生物参与有机质碳同位素分馏过程的草海，△δ13C值也反映了湖泊生产力的变化过程。 7. 青海湖沉积物单一种属介形虫壳体胖真星介（Eucypris inflata）Li/Ca���值与气象记录以及邻近地区都兰和祁连山树轮宽度指数恢复的古温度变化序列的对比研究揭示，介形虫壳体Li/Ca���值与温度呈明显的负相关变化（Li/Ca���值高，温度低；Li/Ca���值低，温度高），表明介形虫壳体Li/Ca���值是一种有效的古温度代用指标。 8. 青海湖沉积物单一种属介形虫壳体胖真星介（Eucypris inflata）Li/Ca���值、氧同位素与反映太阳活动的大气14C含量和冰芯10Be含量的一致性变化表明青海湖地区温度和降雨量的同步变化主要受太阳活动控制。

Gry fabularne jako technika autonomizująca studenta

Publikacja (…) jest zbiorem tekstów poświęconych zagadnieniu autonomii w dydaktyce języków obcych. Teksty te – w obecnej postaci artykułów – stanowią zapis referatów wygłoszonych na konferencji poświęconej temu właśnie, niezwykle istotnemu dla nowoczesnej dydaktyki zagadnieniu. Konferencje tego typu nigdy dotąd w Polsce się nie odbywały. Jest to więc novum na naszym terenie i wielki tytuł do chwały dla uczelni, która podjęła się organizacji takiego wydarzenia i publikacji artykułów opracowanych na podstawie wygłoszonych tam referatów. Dlatego publikację uważam za niezwykle ważną i potrzebną. (z recenzji wydawniczej Prof. dr hab. Hanny Komorowskiej)

Konwencja dotycząca statusu uchod��ców a praktyka turecka. Problem przybyszów zza wschodniej granicy

Celem publikacji jest podjęcie próby przeanalizowania polityki, jaką Turcja prowadzi wobec obcokrajowców poszukujących schronienia na jej terytorium. O ważkości zagadnienia zadecydowała w ostatnich latach przede wszystkim tocząca się w Syrii wojna domowa, w wyniku której na terytorium Turcji znalazło się ponad 700 tysięcy Syryjczyków. Szczególne w tym kontekście kontrowersje budzi fakt stosowania przez Turcję podwójnych standard��w w przedmiocie nadawania imigrantom konwencyjnego statusu uchod��cy. Państwo to, jako jedno z czterech na świecie, w momencie przystępowania do Konwencji dotyczącej statusu uchod��ców i Protokołu nowojorskiego zastrzegło sobie prawo do stosowania w tej materii tzw. kryterium geograficznego. W efekcie, o ile status uchod��cy nadany być może osobom przybywającym zza zachodnich granic Turcji, o tyle uciekinierzy z państw takich, jak Syria, Iran, czy Irak z formalnego punktu widzenia są „poszukującymi schronienia” (tur. sığınmacı). To zaś oznacza brak ich konwencyjnej ochrony. Celem artykułu jest jednak nie tylko przeanalizowanie prawnego i rzeczywistego położenia, w jakim znajdują się ofiary syryjskiej wojny domowej, przybywające na terytorium Turcji, a także próba przewidzenia scenariusza rozwoju tejże sytuacji. Celem uczynienia analizy możliwie najbardziej rzetelną, odwołano się zarówno do anglo, jak i tureckojęzycznych materiałów źród��owych.

Autor filmowy wed��ug przepisów prawa w systemach droit d`auteur i copyright. Zarys problematyki

The aim of the article is to outline the key issues surrounding legal notions of film authorship. For scholars interested in studying the process of production it is extremely important to analyze the status and scope of power of its participants as well as their position in the hierarchy – one of the main sources of priveleges is the fact of being recognized by the law as the author of the work produced. The article depicts the benefits of such situation, but its main aim is to descibe the legal rules of granting the status of the author. Outlined are the issues emerged from the two radically different legal system – european droit d`auteur tradition and american copyright. The first one honours the artists while the other focuses mostly on providing the certainty of the economics, so the actual authors of the work are not that important. The paper points to the fact that – especially in the case of american copyright – the actual (determined by law) situation of a creator may differ significantly from the character of their contribution to the process of producing a film. Analysis of the rules and principles of the law is essential to the understanding of the structural determinants of film production and deserves no less attention than social, political and economic factors.

Investigation of global regulators influencing styrene metabolism and bioplastic synthesis in Pseudomonas putida CA-3

The genetics and biochemistry involved in the biodegradation of styrene and the production of polyhydroxyalkanoates in Pseudomonas putida CA-3 have been well characterised to date. Knowledge of the role played by global regulators in controlling these pathways currently represents a critical knowledge gap in this area. Here we report on our efforts to identify such regulators using mini-Tn5 transposon mutagenesis of the P. putida CA-3 genome. The library generated was subjected to phenotypic screening to identify mutants exhibiting a reduced sensitivity to the effects of carbon catabolite repression of aromatic pathway activity. Our efforts identified a clpX disrupted mutant which exhibited wild-type levels of growth on styrene but significantly reduced growth on phenylacetic acid. RT-PCR analysis of key PACoA catabolon genes necessary for phenylacetic acid metabolism, and SDS-PAGE protein profile analyses suggest that no direct alteration of PACoA pathway transcriptional or translational activity was involved. The influence of global regulators affecting the accumulation of PHAs in P. putida CA-3 was also studied. Phenotypic screening of the mini-Tn5 library revealed a gacS sensor kinase gene disruption resulting in the loss of PHA accumulation capacity in P. putida CA-3. Subsequent SDS-PAGE protein analyses of the wild type and gacS mutant strains identified post-transcriptional control of phaC1 synthase as a key point of control of PHA synthesis in P. putida CA-3. Disruption of the gacS gene in another PHA accumulating organism, P. putida S12, also demonstrated a reduction of PHA accumulation capacity. PHA accumulation was observed to be disrupted in the CA-3 gacS mutant under phosphorus limited growth conditions. Over-expression studies in both wild type CA-3 and gacS mutant demonstrated that rsmY over-expression in gacS disrupted P. putida CA-3 is insufficient to restore PHA accumulation in the cell however in wild type cells, over-expression of rsmY results in an altered PHA monomer compositions.

Variaciones temporales en las determinaciones de Ca, Mg y K intercambiables

p.317-323

Edta como extractante universal : I- cationes mayores (Ca, Mg y K)

p.133-137

[Book review] Piero della Francesca: A Mathematician's art by J.V. Field, Yale University Press.

Review of the book 'Piero della Francesca: A Mathematician’s Art' by J.V. Field, Yale University Press, 420 pp, £35 ISBN 0300103425.

Ca(2+)-activated Cl(-) current in sheep lymphatic smooth muscle.

Freshly dispersed sheep mesenteric lymphatic smooth muscle cells were studied at 37 degrees C using the perforated patch-clamp technique with Cs(+)- and K(+)-filled pipettes. Depolarizing steps evoked currents that consisted of L-type Ca(2+) [I(Ca(L))] current and a slowly developing current. The slow current reversed at 1 +/- 1.5 mV with symmetrical Cl(-) concentrations compared with 23.2 +/- 1.2 mV (n = 5) and -34.3 +/- 3.5 mV (n = 4) when external Cl(-) was substituted with either glutamate (86 mM) or I(-) (125 mM). Nifedipine (1 microM) blocked and BAY K 8644 enhanced I(Ca(L)), the slow-developing sustained current, and the tail current. The Cl(-) channel blocker anthracene-9-carboxylic acid (9-AC) reduced only the slowly developing inward and tail currents. Application of caffeine (10 mM) to voltage-clamped cells evoked currents that reversed close to the Cl(-) equilibrium potential and were sensitive to 9-AC. Small spontaneous transient depolarizations and larger action potentials were observed in current clamp, and these were blocked by 9-AC. Evoked action potentials were triphasic and had a prominent plateau phase that was selectively blocked by 9-AC. Similarly, fluid output was reduced by 9-AC in doubly cannulated segments of spontaneously pumping sheep lymphatics, suggesting that the Ca(2+)-activated Cl(-) current plays an important role in the electrical activity underlying spontaneous activity in this tissue. PMID: 11029279 [PubMed - indexed for MEDLINE]

Ca2+ current and Ca(2+)-activated chloride current in isolated smooth muscle cells of the sheep urethra.

1. Isolated sheep urethral cells were studied using the perforated patch clamp technique (T = 37 degrees C). Depolarizing steps ranging from -40 to -10 mV evoked an inward current that peaked within 10 ms and a slower inward current. Stepping back to the holding potential of -80 mV evoked large inward tail currents. All three currents were abolished by nifedipine (1 microM). Substitution of external Ca2+ with Ba2+ resulted in potentiation of the fast inward current and blockade of the slow current and tails. 2. Changing the chloride equilibrium potential (ECl) from 0 to +27 mV shifted the reversal potential of the tail currents from 1 +/- 1 to 27 +/- 1 mV (number of cells, n = 5). Chloride channel blockers, niflumic acid (10 microM) and anthracene-9-carboxylic acid (9AC, 1 mM), reduced the slow current and tails suggesting that these were Ca(2+)-activated Cl- currents, ICl(Ca). 4. Caffeine (10 mM) induced currents that reversed at ECl and were blocked by niflumic acid (10 microM). 5. In current clamp mode, some cells developed spontaneous transient depolarizations (STDs) and action potentials. Short exposure to nifedipine blocked the action potentials and unmasked STDs. In contrast, 9AC and niflumic acid reduced the amplitude of the STDs and blocked the action potentials. 6. In conclusion, these cells have both L-type ICa and ICl(Ca). The former appears to be responsible for the upstroke of the action potential, while the latter may act as a pacemaker current.

Identification in the Ca II K spectral region of sharp-lined B- type stars

Previous Call K observations of the B-type star HD 83206 have revealed putative high-velocity interstellar clouds (HVCs) at Local Standard of Rest (LSR) velocities of -80 and -110 km s(- 1). Similar results were also found for the sightline towards HD135485. In this article, we show that these absorption lines are in fact due tr, stellar SII features. As the Call K absorption line in B-type stars is often used to assess the presence and distance of HVCs. we also present a very high quality spectrum of HD 83206 in the Ca II K region (similar to+/-4 Angstrom or +/-300 km s(-1)), so that in the future confusion between stellar lines and HVC features may be avoided.

Alien gosd in the new epics: Noah remythologised through the ancient astronaut hypothesis in Abel's Montagut's "La gesta d'Utnoa"

Modern scientific world-view has undermined traditional myths, the functional survival of which seems to depend today in the West on a positivist justification. This would place them in the field of real History, through their study and revitalization by pseudoscientific disciplines such as the Atlantis and the ancient astronaut hypotheses. These have inspired new epic poems in (regular) verse that combine classic and/or biblical myths with a (pseudo)scientific modern world-view. For example, the critical rewriting of Noah’s myth by using the ancient astronaut hypothesis as a fictional device to produce a contemporary kind of plausibility allowed Abel Montagut to renew epic poetry, updating it also by adopting science fiction chronotopes in order to structure his fictional construction and to generate a high ethical sense for our time. Thus, his Poemo de Utnoa (1993) / La gesta d���Utnoa (1996), which has become a major classic of the literature in Esperanto thanks to its original version in this language, is a landmark of both science fiction and neo-biblical epics. This poem is written from a secular and purely literary perspective.