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991.
The carceral boom in post-Civil Rights America results not from profit-seeking but from state-crafting. Accordingly, we must slay the chimera of the “Prison Industrial Complex” and forsake its derived tale of the “Prisoner Reentry Industry.” This murky economic metaphor is doubly misleading: first, most released convicts experience not reentry but ongoing circulation between the prison and their dispossessed neighborhoods; second, the institutions entrusted with supervising them are not market operators but elements of the bureaucratic field as characterized by Pierre Bourdieu. Post-custodial supervision is a ceremonial component of “prisonfare,” which complements “workfare” through organizational isomorphism, and partakes of the neoliberal reengineering of the state. Reentry outfits are not an antidote to but an extension of punitive containment as government technique for managing problem categories and territories in the dualizing city. To capture the glaring economic irrationality and bureaucratic absurdities of the oversight of felons behind as well as beyond bars, our theoretical inspiration should come not from the radical critique of capitalism but from the neo-Durkheimian sociology of organization and the neo-Weberian theory of the state as a classifying and stratifying agency.  相似文献   
992.
We performed a comparative analysis of the genetic diversity and structure of two congeneric tree species, one critically endangered, with only 21 known individuals in the wild, Dimorphandra wilsonii, and the other widely distributed Dimorphandra mollis. Eight populations of D. mollis and all known trees of D. wilsonii, from three areas, were screened for variability with ISSR markers. Percentage of polymorphic bands, Nei's gene diversity and Shannon's index were considerably lower in D. wilsonii (P = 40.0%, h = 0.124 and I = 0.190), as compared to D. mollis (P = 70.4%, h = 0.190 and I = 0.297). Bayesian clustering showed that D. wilsonii individuals are clustered in three populations, which had high differentiation among them. Several measures for their conservation were suggested: protection of all extant populations, ex situ conservation of seeds, production of saplings in nurseries and foundation of new populations in reserve areas.  相似文献   
993.
Although light is essential for photosynthesis, excess light can damage the photosynthetic apparatus and deregulate other cellular processes. Thus, protective integrated regulatory responses that can dissipate excess of absorbed light energy and simultaneously optimize photosynthesis and other cellular processes under variable light conditions can prove highly adaptive. Here, we show that the local and systemic responses to an excess light episode are associated with photoelectrophysiological signaling (PEPS) as well as with changes in nonphotochemical quenching and reactive oxygen species levels. During an excess light incident, PEPS is induced by quantum redox changes in photosystem II and in its proximity and/or by changes in glutathione metabolism in chloroplasts. PEPS is transduced, at least in part, by bundle sheath cells and is light wavelength specific. PEPS systemic propagation speed and action potential are dependent on ASCORBATE PEROXIDASE2 function. Excess light episodes are physiologically memorized in leaves, and the cellular light memory effect is specific for an excess of blue (450 nm) and red (650 nm) light of similar energy. It is concluded that plants possess a complex and dynamic light training and memory system that involves quantum redox, reactive oxygen species, hormonal, and PEPS signaling and is used to optimize light acclimation and immune defenses.  相似文献   
994.
The summation of contractile forces of motor units (MUs) was analyzed by comparing the recorded force during parallel stimulation of two and four individual MUs or four groups of MUs to the algebraic sum of their individual forces. Contractions of functionally-isolated single MUs of the medial gastrocnemius muscle were evoked by electrical stimulation of thin filaments of the split L5 or L4 ventral roots of spinal nerves. Additionally, contractions of large groups of MUs were evoked by stimuli delivered to four parts of the divided L5 ventral root. Single twitches, 40 Hz unfused tetani, and 150 Hz fused maximum tetani were recorded. In these experimental situations the summation was more effective for unfused tetani than for twitches or maximum tetani. The results obtained for pairs of MUs were highly variable (more- or less-than-linear summation), but coactivation of more units led to progressively weaker effects of summation, which were usually less-than-linear in comparison to the algebraic sums of the individual forces. The variability of the results highlights the importance of the structure of the muscle and the architecture of its MUs. Moreover, the simultaneous activity of fast and slow MUs was considerably more effective than that of two fast units.  相似文献   
995.
The contractile properties of motor units (MUs) were electrophysiologically investigated in the medial gastrocnemius (MG) muscle in 17 Wistar three-month-old female rats: 14, 30, 90 and 180 days after the total transection of the thoracic spinal cord and compared to those in intact (control) rats. A sag phenomenon, regularly observed in unfused tetani of fast units in intact animals at 40 Hz stimulation, almost completely disappeared in spinal rats. Therefore, the MUs of intact and spinal rats were classified as fast or slow types basing on 20 Hz tetanus index, the value of which was lower or equal 2.0 for fast and higher than 2.0 for slow MUs. The MUs composition of MG muscle changed with time after the spinal cord transection: an increasing proportion of fast fatigable (FF) units starting one month after injury and a disappearance of slow (S) units within the three months were observed. In all MUs investigated the twitch contraction and half-relaxation time were significantly prolonged after injury (p < 0.01, Mann–Whitney U-test). Moreover, a decrease of the fatigue index for fast resistant (FR) and slow MUs was observed in subsequent groups of spinal rats. No significant changes were found between twitch forces in all MU types of spinal animals (p > 0.05). However, due to a decrease of the maximal tetanic force, a significant rise of the twitch-to-tetanus ratio of all MUs in spinal rats was detected (p < 0.01). The considerable reduction of ability to potentiate the force was noticed for fast, especially FF type MUs. In conclusion, the spinal cord transection leads to changes in the proportion of the three MU types in rat MG muscle. The majority of changes in MUs’ contractile properties were developed progressively with time after the spinal cord injury. However, the most intensive alterations of twitch-time parameters were observed in rats one month after the transection.  相似文献   
996.
The subject of these studies was synthesis and determination of biological properties of a series of insect peptides, such as alloferon, Any‐GS and their analogues. The synthesis of 14 peptides was performed by the solid‐phase method. Biological effect of these peptides was evaluated by the antiviral test against Human Herpes Virus type 1 (HHV‐1) in vitro using a Vero cell line. It was found that the investigated peptides inhibit the replication of HHV‐1 in Vero cells. Copyright © 2010 European Peptide Society and John Wiley & Sons, Ltd.  相似文献   
997.
This work contributes to highlight the benefits of pseudoproline dipeptides introduction in difficult SPPS. We show how a slight modification in the positioning choice conditioned the synthesis achievement of a 54 amino acid long caveolin‐1 peptide encompassing the intramembrane domain. Furthermore, we report a side reaction correlated with the coupling steps and generating truncated fragments with a mass deviation of + 42 Da. Considering the need of structural data for membrane proteins, most of which are considered as prevalent therapeutic targets, chemical synthesis provides an interesting alternative pathway to obtain hydrophobic domains by pushing back the frontiers of conventional RP methods of purification. Copyright © 2009 European Peptide Society and John Wiley & Sons, Ltd.  相似文献   
998.
Dehydrobutyrine is the most naturally occurring dehydroamino acid. It is also the simplest dehydroamino acid having the geometrical isomers E/Z. To investigate its conformational properties, a theoretical analysis was performed on N‐acetyl‐α,β‐dehydrobutyrine N′‐methylamides, Ac‐(E)‐ΔAbu‐NHMe and Ac‐(Z)‐ΔAbu‐NHMe, as well as the dehydrovaline derivative Ac‐ΔVal‐NHMe. The ?, ψ potential energy surfaces and the localised conformers were calculated at the B3LYP/6‐311 + + G(d,p) level of theory both in vacuo and with inclusion of the solvent (chloroform, water) effect (SCRF method). The X‐ray crystal structures of Ac‐(Z)‐ΔAbu‐NHMe and Ac‐ΔVal‐NHMe were determined at 85 and 100 K, respectively. The solid‐state conformational preferences for the studied residues have been analysed and compared with the other related structures. Despite the limitations imposed by the Cα = Cβ double bond on the topography of the side chains, the main chains of the studied dehydroamino acids are more flexible than in standard alanine. The studied dehydroamino acids differ in their conformational preferences, which depend on the polarity of the environment. This might be a reason why the nature quite precisely differentiates between ΔVal and each of the ΔAbu isomers, and why, particularly so with the latter, they are used as a conformational tool to influence the biological action of usually small, cyclic dehydropeptides. Copyright © 2010 European Peptide Society and John Wiley & Sons, Ltd.  相似文献   
999.
Enzymes in the newly described rumen bacterium, Treponema zioleckii strain kT, capable of digesting Timothy grass fructan, inulin, and sucrose were identified and characterized. Two specific endolevanases and one non-specific β-fructofuranosidase were found in a cell-free extract. The molecular weight of the endolevanases were estimated to be 60 and 36 kDa, whereas that of β-fructofuranosidase, 87 kDa. The former of the specific enzymes was associated with the outer membrane, while the latter and the non-specific β-fructofuranosidase, with the periplasm or cytosol. The Km and Vmax for Timothy grass fructan degradation by endolevanase were 0.27% and 15.75 μM fructose equivalents × mg protein?1 × min?1, those for sucrose and inulin digestion by β-fructofuranosidase were 1.35 × 10?3 M and 1.73 μM hexoses × mg protein?1 × min?1 and 1.77% and 1.83 μM hexoses × mg protein?1 × min?1, respectively.  相似文献   
1000.
Location of the loci that control preharvest sprouting and alpha-amylase activity in rye was studied based on intercross S120×S76, consisting of 110 genotypes of F2 and F3 progenies. The genetic map currently consists of 141 loci distributed in 11 linkage groups, covering a distance of 506.4 cM, and was enriched during this study with 24 sequence-specific markers (7 SCARs, 7 SSRs, and 10 STSs). The extended map was applied for composite interval mapping of the loci controlling preharvest sprouting and α-amylase activity, revealing 3 significant QTLs for preharvest sprouting, located on chromosomes 3R, 5R and 6R (in 1999), and one QTL for α-amylase activity found on chromosome 2R (in 2000).  相似文献   
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