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1.
Sally Engle Merry 《American anthropologist》2001,103(1):16-29
The new urban social order depends on a complex combination of systems of punishment, discipline, and security. Scholars drawing on Foucault's analysis of the art and rationality of governance, or govemmentality, have explored how urban social orders are increasingly based on the governance of space rather than on the discipline of offenders or the punishment of offenses. The new urban social order is characterized by privatized security systems and consumer-policed spaces such as malls. Gender violence interventions represent another deployment of spatial forms of govemmentality. Over the last two decades, punishment of batterers has been augmented by disciplinary systems that teach batterers new forms of masculinity and by security systems for women based on spatial separation. In the postmodern city, spatial govemmentality is integrally connected with punishment and discipline. These new forms of governance circulate globally along with neoliberal ideas of the diminished state, [gender violence, govemmentality, urban society, globalization, law] 相似文献
2.
M J Engle M Dooley D J Brown 《Biochemical and biophysical research communications》1987,145(1):397-401
Fetal rabbit lungs from 23 day gestation animals were used to investigate the potential role of lactate as a substrate for fetal lung glycogen synthesis. Fetal lactate dehydrogenase activity was approximately twice that found in the adult lung, while the activity of phosphoenolpyruvate carboxykinase was elevated fourfold over the adult value. Pyruvate carboxylase activities were similar in both fetal and adult lungs. Studies employing fetal lung explants in organ culture indicated that the presence of both glucose and lactate may be necessary for glycogen accumulation in the developing fetal lung. These data support the hypothesis that lactate is an important precursor for fetal lung glycogen. 相似文献
3.
Ultraviolet Radiation Effects on Ehrlich Ascites Tumor Cells : Observations Using a Flying Spot Ultraviolet Microscope 总被引:1,自引:1,他引:0 下载免费PDF全文
Jerome J. Freed James L. Engle George T. Rudkin Jack Schultz 《The Journal of cell biology》1959,5(2):205-215
A flying spot ultraviolet microscope, employing a fast scan and pulsed operation of the raster, has been used to induce radiation damage in ascites tumor slide cultures, and to study by time-lapse cinematography the progressive stages of cell damage. The cells observed came from a strain (EF7) of the Ehrlich ascites carcinoma. Irradiated cells were found to show a characteristic syndrome of damage, involving blebbing at the cell surface, while control cells in the adjacent areas of the preparation remained unchanged. The end of the blebbing period is marked by swelling of the cells, and the time taken for this phenomenon to occur was used as a measure of the severity of the damage. It was found that the time required for swelling is dependent on the size of the dose employed, as well as on the sensitivity of the cells. This latter sensitivity was found to decline as the physiological age of the tumor increased. If ultraviolet illumination below 255 mµ is excluded, no symptoms of damage occur, even when very large doses are used. These observations are discussed in relation to the nature of the system in the cell which is affected. 相似文献
4.
DNA sequences were determined for three to five alleles of the bride-of-
sevenless (boss) gene in each of four species of Drosophila. The product of
boss is a transmembrane receptor for a ligand coded by the sevenless gene
that triggers differentiation of the R7 photoreceptor cell in the compound
eye. Population parameters affecting the rate and pattern of molecular
evolution of boss were estimated from the multinomial configurations of
nucleotide polymorphisms of synonymous codons. The time of divergence
between D. melanogaster and D. simulans was estimated as approximately 1
Myr, that between D. teissieri and D. yakuba as approximately 0.75 Myr, and
that between the two pairs of sibling species as approximately 2 Myr. (The
boss genes themselves have estimated divergence times approximately 50%
greater than the species divergence times.) The effective size of the
species was estimated as approximately 5 x 10(6), and the average mutation
rate was estimated as 1-2 x 10(-9)/nucleotide/generation. The ratio of
amino acid polymorphisms within species to fixed differences between
species suggests that approximately 25% of all possible single-step amino
acid replacements in the boss gene product may be selectively neutral or
nearly neutral. The data also imply that random genetic drift has been
responsible for virtually all of the observed differences in the portion of
the boss gene analyzed among the four species.
相似文献
5.
Sayan Mukherjee Pablo Tamayo Simon Rogers Ryan Rifkin Anna Engle Colin Campbell Todd R Golub Jill P Mesirov 《Journal of computational biology》2003,10(2):119-142
A statistical methodology for estimating dataset size requirements for classifying microarray data using learning curves is introduced. The goal is to use existing classification results to estimate dataset size requirements for future classification experiments and to evaluate the gain in accuracy and significance of classifiers built with additional data. The method is based on fitting inverse power-law models to construct empirical learning curves. It also includes a permutation test procedure to assess the statistical significance of classification performance for a given dataset size. This procedure is applied to several molecular classification problems representing a broad spectrum of levels of complexity. 相似文献
6.
7.
The contractile basis of amoeboid movement: V. The control of gelation, solation, and contraction in extracts from dictyostelium discoideum 总被引:29,自引:22,他引:7 下载免费PDF全文
Motile extracts have been prepared from Dictyostelium discoideum by homogenization and differential centrifugation at 4 degrees C in a stabilization solution (60). These extracts gelled on warming to 25 degrees Celsius and contracted in response to micromolar Ca++ or a pH in excess of 7.0. Optimal gelation occurred in a solution containing 2.5 mM ethylene glycol-bis (β-aminoethyl ether)N,N,N',N'-tetraacetate (EGTA), 2.5 mM piperazine-N-N'-bis [2-ethane sulfonic acid] (PIPES), 1 mM MgC1(2), 1 mM ATP, and 20 mM KCI at ph 7.0 (relaxation solution), while micromolar levels of Ca++ inhibited gelation. Conditions that solated the gel elicited contraction of extracts containing myosin. This was true regardless of whether chemical (micromolar Ca++, pH >7.0, cytochalasin B, elevated concentrations of KCI, MgC1(2), and sucrose) or physical (pressure, mechanical stress, and cold) means were used to induce solation. Myosin was definitely required for contraction. During Ca++-or pH-elicited contraction: (a) actin, myosin, and a 95,000-dalton polypeptide were concentrated in the contracted extract; (b) the gelation activity was recovered in the material sqeezed out the contracting extract;(c) electron microscopy demonstrated that the number of free, recognizable F-actin filaments increased; (d) the actomyosin MgATPase activity was stimulated by 4- to 10-fold. In the absense of myosin the Dictyostelium extract did not contract, while gelation proceeded normally. During solation of the gel in the absense of myosin: (a) electron microscopy demonstrated that the number of free, recognizable F- actin filaments increased; (b) solation-dependent contraction of the extract and the Ca++-stimulated MgATPase activity were reconstituted by adding puried Dictyostelium myosin. Actin purified from the Dictyostelium extract did not gel (at 2 mg/ml), while low concentrations of actin (0.7-2 mg/ml) that contained several contaminating components underwent rapid Ca++ regulated gelation. These results indicated : (a) gelation in Dictyostelium extracts involves a specific Ca++-sensitive interaction between actin and several other components; (b) myosin is an absolute requirement for contraction of the extract; (c) actin-myosin interactions capable of producing force for movement are prevented in the gel, while solation of the gel by either physical or chemical means results in the release of F-actin capable of interaction with myosin and subsequent contraction. The effectiveness of physical agents in producting contraction suggests that the regulation of contraction by the gel is structural in nature. 相似文献
8.
Both oxolinic acid and coumermycin A1, inhibitors of DNA gyrase, block DNA synthesis in Escherichia coli. At low concentrations of oxolinic acid, the rate of bacterial DNA synthesis first declines rapidly but then gradually increases. This gradual increase in synthesis rate depended on the presence of wild-type recA and lexA genes; mutations in either gene blocked the increase in synthesis rate. In such mutants, oxolinic acid caused a rapid decline, followed by a slow, further decrease in DNA synthesis rate. Coumermycin A1, however, produced a more gradual decline in synthesis rate which is unaffected by defects in the recA or lexA genes. An additional difference between the two drugs was observed in a dnaA mutant, in which initiation of replication is temperature sensitive. Low concentrations of oxolinic acid, but not coumermycin A1, reduced thermal inhibition of DNA synthesis rate. 相似文献
9.
Previous reports have suggested the possibility of extensive structural homology between human erythrocyte bisphosphoglycerate synthase (glycerate-1,3-P2 leads to glycerate-2,3-P2) and phosphoglycerate mutase (glycerate-3-P in equilibrium glycerate-2-P). This study lends credence to that conjecture through comparative physicochemical investigations involving peptide mapping, circular dichroism, and immunological techniques. The data indicate that despite differences in function, both enzymes apparently manifest a high degree of similarity in primary, secondary, and tertiary structure. Mapping data also indicate that each protein is comprised of two apparently identical subunits. 相似文献