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1.
In this paper, I read Leïla Sebbar’s staging in her novel Shérazade: 17 ans, brune, frisée, les yeux verts of the resistance by children of North African and other immigrants in the early 1980s to the French state’s cartographic modes and documents of control. The paper will consider the many uses to which the map was put by the French state in its colonization of North Africa and particularly Algeria, and later in its attempts to control the banlieues its policies of citizenship and cartographic control yielded on the margins of Paris. In this context, I will explore the ways in which the novel’s characters, living clandestinely in a squatt, simultaneously resist, put to use, and even supercede state documents of control as they disrupt everyday life and conduct heists across the city of Paris. The paper will explore unofficial cartographies of Paris, from those afforded by the radios libres and alternative publications such as Libération and Sans Frontièrez, to oral and almost proverbial networks of knowledge criss-crossing the city of Paris, while also tracing the uses to which supplemental cartographic sketches and counterfeit identity cards are put in the pages of the novel. The paper will be in dialogue with theoretical and critical formulations of space, cartography, and state control put forward by Michel de Certeau, Henri Lefebvre, Michel Foucault, and Tom Conley. The paper will conclude with a consideration of the means and limits of resistance by the novel’s characters in the context of this body of theory and criticism.  相似文献   
2.
Summary Locust lipoproteins (lipophorins) were localized by indirect immunofluorescence- and immunogold labelling in cryosections of dorsolongitudinal flight muscles. Immunolabelling was performed with monoclonal antibodies against apolipoprotein epitopes that are exposed at the surfaces of the lipophorin particles. Both at rest and during flight, lipophorins were located only in the wider spaces of the extracellular matrix, in the basement membranes of the individual muscle fibers and in the extracellular spaces that surround interfibrillar tracheoles. No internalization of lipophorins by the flight muscle cells was observed. Our results indicate that the unloading of lipophorins at the flight muscles is an extracellular event. Similarities with the vertebrate system of chylomicron and very-low-density lipoprotein degradation are discussed.  相似文献   
3.
Correlative light, high-voltage electron and conventional electron microscopic methods were used to investigate digestion in two allogromiid foraminiferans, Allogromia sp., strain NF, and A. laticollaris Arnold. Microscopic observations showed that bacterial prey are phagocytosed by reticulopodia and are transported to the allogromiid cell body within blister-like phagosomes. Larger prey (algae, diatoms) are transported along the reticulopodial surface and are either stored extrathalamously or phagocytosed at the oral opening (peduncle). Studies of allogromiids optimally fixed and labeled with an extracellular-space label (colloidal thorium) showed that phagocytosed prey are completely enclosed by a plasma membrane envelope; this finding was corroborated by a serial-section three-dimensional reconstruction of the oral zone of one allogromiid. Cytochemical staining for acid phosphatase showed that lysosomes are absent from reticulopods but abundant in the cell body, particularly in the oral zone cytoplasm. We conclude that digestion in allogromiid foraminiferans is accomplished by a vacuole-based digestive apparatus and not by extracellular digestion within a lacunary system, as has been suggested in earlier studies.  相似文献   
4.
Summary Many neurones are extremely invaginated and possess branching processes, axons and dendrites. In general, they are surrounded by a restricted diffusion space. Many of these cells exhibit large, slow potential changes during the passage of current across their membranes. Whenever currents cross membranes separating aqueous solutions, differences in transport numbers of the major permeant ions give rise to local concentration changes of these ions adjacent to the membranes, which will result in various electrical and osmotic effects. These transport number effects are expected to be enhanced by the presence of membrane invaginations. Dendrites are equivalent to reversed invaginations and there should be significant changes in concentrations of permeant ions within them. In general, the effects of such changes on the electrical response of a cell will be greater when the concentration of a major permeant ion is low. The effects have been modelled in terms of two nondimensional parameters: the invagination transport number parameter and the relative area occupied by the invaginations A. If these two parameters are known, the magnitudes and time course of the slow potential changes can immediately be estimated and the time course converted to real time, if the length of the invaginations (l) and ionic diffusion coefficient (D) within them are also known. Both analytical and numerical solutions have been given and predictions compared. It is shown that in the case of large currents and potentials the analytical solution predictions will underestimate the magnitudes and rates of onset of the voltage responses. The relative magnitude of the transport number effect within the invaginations (or dendrites) and other transport number contributions to slow potential changes have also been assessed and order-of-magnitude values of these are estimated for some biological data.  相似文献   
5.
A new chemolithotrophic nitrite-oxidizing bacterium, for which the name Nitrospira marina is proposed, was isolated from the Gulf of Maine. N. marina is a Gramnegative curved rod which may form spirals with 1 to 12 turns. Cells have a unique periplasmic space and lack intracytoplasmic membranes and carboxysomes. N. marina is an obligate chemolithotroph, but best growth is obtained in a mixotrophic medium. N. marina may be one of the most prevalent nitrite-oxidizing bacteria in some oceanic environments. Type strain is field with American Type Culture Collection (ATCC 43039).  相似文献   
6.
Z. Rengel 《Plant and Soil》1990,128(2):185-189
Ammonium acetate and BaCl2-triethanolamine were used to desorb Mg2+ from the root Donnan free space (DFS) of 23-d-old ryegrass (Lolium multiflorum Lam. cvs. Gulf and Wilo). Amounts of desorbed Mg2+ increased with the increase in Mg2+ activity of the nutrient solution. Slightly less Mg2+ was desorbed by Ba2+ than by NH4 +. Previously published data on short-term net Mg2+ uptake by intact 23-d-old ryegrass plants of the two cultivars were linearly related to the amount of exchangeable Mg+ desorbed from the root DFS (r2=0.90 and 0.81 for the desorption by NH4 + and Ba2+, respectively). A sward of Mg2+ ions attracted to the negative charges of the cell surface is suggested to represent a part of a pool of Mg2+ available for active transport through the plasmalemma.  相似文献   
7.
A combinatorial sequence space (CSS) model was introduced to represent sequences as a set of overlapping k-tuples of some fixed length which correspond to points in the CSS. The aim was to analyze clusterization of protein sequences in the CSS and to test various hypotheses about the possible evolutionary basis of this clusterization. The authors developed an easy-to-use technique which can reveal and analyze such a clusterization in a multidimensional CSS. Application of the technique led to an unexpectedly high clusterization of points in the CSS corresponding to k-tuples from known proteins. The clusterization could not be inferred from nonuniform amino acid frequencies or be explained by the influence of homologous data. None of the tested possible evolutionary and structural factors could explain the clusterization observed either. It looked as if certain protein sequence variations occurred and were fixed in the early course of evolution. Subsequent evolution (predominantly neutral) allowed only a limited number of changes and permitted new variants which led to preservation of certain k-tuples during the course of evolution. This was consistent with the theory of exon shuffling and protein block structure evolution. Possible applications of sequence space features found were also discussed.Correspondence to: H.A. Lim  相似文献   
8.
Gravitropically-stimulated seedlings show autotropism in weightlessness   总被引:1,自引:0,他引:1  
In a spaceflight experiment, autotropism by oat ( Avena sativa L.) coleoptiles following gravitropic responses was prominent in weightlessness: counter-reactions led to the straightening of the curved coleoptiles. This was not the case during clinorotation on earth. The autotropic reactions appeared to be related to the stimulus received during the stimulus period, i.e. the greater the response the greater the autotropic counter-reaction. Previous models of the gravitropic system which predicted that coleoptiles would not straighten in weightlessness are disproved. A modification to one of the models is proposed which includes the autotropic response observed in spaceflight. The nature of the counter-reactions in the absence of gravitropic stimulation is discussed.  相似文献   
9.
No-salt flowthrough hydrophobic interaction chromatography (HIC) has been shown to effectively remove process and product-related impurities from bioprocess streams. In this publication, a panel of six antibodies has been used to demonstrate operating principles for the application of no-salt flowthrough HIC in antibody purification processes. The results indicate that no-salt flowthrough HIC provides robust aggregate clearance across operating conditions including flow rate, and variations in resin ligand density. Additionally, HMW reduction has an optimal pH range relative to the isoelectric point of each molecule and high molecular weight (HMW) reduction can be improved by altering the total protein load and/or HMW concentration to drive binding of high molecular weight species to the resin.  相似文献   
10.
实验分别在出生后4周龄的幼年和成年鲁氏菊头蝠(Rhinolophusrouxi)上进行。使用移动声刺激装置,高频喇叭可在动物头部前方水平方向180度、垂直方向60度的范围内移动。玻璃微电极记录单个神经元的听反应。实验考察了幼年和成年动物下丘神经元的听空间特性,共观察了301个神经元,其中幼年动物148个,成年动物153个。结果表明,4周龄的幼年动物下丘听神经元已表现出方向敏感性,即每个听神经元均有一个特定的最佳反应中心和反应域。但神经元听反应中心在听空间的分布相当弥散,大多数位于对侧水平方向20—80度、垂直方向上下15度范围内。而成年动物听神经元反应中心的分布则相当集中,局限地分布于对侧水平方向28-50度,垂直方向0—10度范围内,两者构成明显差异。  相似文献   
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