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Crime and punishment with habit formation

Teles, Vladimir Kuhl; Andrade, Joaquim Pinto de
Fonte: Fundação Getúlio Vargas Publicador: Fundação Getúlio Vargas
Tipo: Trabalho em Andamento
Português
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16.71%
Moral concepts affect crime supply. This idea is modelled assuming that illegal activities is habit forming. We introduce habits in a intertemporal general equilibrium framework to illegal activities and compare its outcomes with a model without habit formation. The findings are that habit and crime presents a non linear relationship that hinges upon the level of capital and habit formation. It is possible to show that while the effect of habit on crime is negative for low levels o habit formation it becomes positive as habits goes up. Secondly habit reduces the marginal effect of illegal activities return on crime. Finally, the effect of habit on crime depends positively on the amount of capital. This could explain the relationship between size of cities and illegal activity.

Corruption in Northeast Brazil: A qualitative approach for socio-economic development

Rocha de Sousa, Miguel; Carneiro, Fernanda
Fonte: Universidade de Évora Publicador: Universidade de Évora
Tipo: Aula
Português
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16.71%
This study starts from a literature review on corruption, departing from its ancient roots, going to its modern prevalence and perception. We focus our approach on the NE Brazil region. The main contribution is that it is the first qualitative approach which assesses corruption specifically in the NE Brazil. We use 21 interviews to political actors: senators and deputies, collected along one and half year in Brasilia, the capital of Brazil, in 2012-13, as in one of us (Carneiro’s Phd, 2013). A causal link is established between corruption and under-development, namely at its socioeconomic roots. We believe this study is path-breaking, because as it focus on one of the most depressed regions in Brazil, can serve as toolkit for socio-economic development policies in Latin America. The innovative approach comes from the fact of using qualitative text analysis to measure the impact of corruption on the (official) discourse on development. A tentative conclusion, with some recommendations for alike situations is attempted by abridging the different socio-economic and political dimensions. We also use Sen’s, Furtado’s, Rose-Ackerman’s among a few concepts to cross the notions of corruption in NE’s discourse with their theoretical framework...

Human immunodeficiency virus type 1 (HIV-1) inhibition, DNA-binding, RNA-binding, and ribosome inactivation activities in the N-terminal segments of the plant anti-HIV protein GAP31.

Lee-Huang, S; Kung, H F; Huang, P L; Bourinbaiar, A S; Morell, J L; Brown, J H; Huang, P L; Tsai, W P; Chen, A Y; Huang, H I
Fonte: PubMed Publicador: PubMed
Tipo: Artigo de Revista Científica
Publicado em 06/12/1994 Português
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17.9%
GAP31 (gelonium anti-HIV protein of 31 kDa) is an anti-HIV protein which we have identified and purified from a medicinal plant, Gelonium multiflorum. It is capable of inhibiting HIV-1 infection and replication. GAP31 also exhibits DNA topoisomerase inhibitor activity and RNA N-glycosidase activity. The ability of GAP31 to interrupt both DNA and RNA functions may be related to its multiple antiviral actions. To define the roles of these activities in the anti-HIV action of GAP31, a series of peptides corresponding to the N-terminal segment of GAP31 were synthesized and assayed for the aforementioned activities of the parent molecule. A 33-aa segment (KGATYITYVNFLNELRVKTKPEGNSHGIPSLRK) designated as K10-K42 is the shortest peptide necessary and sufficient for HIV-1 inhibition, DNA and RNA binding, and ribosome inactivation. The peptides were 2-5 orders of magnitude less active than GAP31. Truncation of 19 aa from the C terminus of K10-K42 resulted in the loss of all of these activities. On the other hand, deletion of N-terminal residues to give E23-K42 did not alter ribosome-inactivation activity but eliminated the other activities. These findings permit identification of a 7-aa sequence, KGATYIT, at the N terminus of K10-K42 that is critical for DNA binding and RNA binding...

Hexameric RSF1010 helicase RepA: the structural and functional importance of single amino acid residues

Ziegelin, Günter; Niedenzu, Timo; Lurz, Rudi; Saenger, Wolfram; Lanka, Erich
Fonte: Oxford University Press Publicador: Oxford University Press
Tipo: Artigo de Revista Científica
Publicado em 15/10/2003 Português
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16.71%
In the known monoclinic crystals the 3-dimensional structure of the hexameric, replicative helicase RepA encoded by plasmid RSF1010 shows 6-fold rotational symmetry. In contrast, in the cubic crystal form at 2.55 Å resolution described here RepA has 3-fold symmetry and consists of a trimer of dimers. To study structure–function relationships, a series of repA deletion mutants and mutations yielding single amino acid exchanges were constructed and the respective gene products were analyzed in vivo and in vitro. Hexamerization of RepA occurs via the N-terminus and is required for NTP hydrolysis. The C-terminus is essential both for the interaction with the replication machinery and for the helicase activity. Functional analyses of RepA variants with single amino acid exchanges confirmed most of the predictions that were based on the published 3-dimensional structure. Of the five motifs conserved in family 4 helicases, all residues conserved in RepA and T7 gp4 helicases participate in DNA unwinding. Residues K42, E76, D77, D139 and H178, proposed to play key roles in catalyzing the hydrolysis of NTPs, are essential for RepA activity. Residue H178 of motif H3 couples nucleotide consumption to DNA strand separation.

Primary structure of the Escherichia coli serotype K42 capsular polysaccharide and its serological identity with the Klebsiella K63 polysaccharide.

Niemann, H; Chakraborty, A K; Friebolin, H; Stirm, S
Fonte: PubMed Publicador: PubMed
Tipo: Artigo de Revista Científica
Publicado em /01/1978 Português
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27.69%
The Escherichia coli K42 capsular polysaccharide consists of leads to 3)-alpha-D-Galp-(1 leads to 3)-alpha-D-GalUAp-(1 leads to 3)-alpha-L-Fucp-(1 leads to repeating units. The E. coli K42 and Klebsiella K63 antigens are serologically identical.

Surface exposure of O1 serotype lipopolysaccharide in Klebsiella pneumoniae strains expressing different K antigens.

Tomás, J M; Camprubi, S; Merino, S; Davey, M R; Williams, P
Fonte: PubMed Publicador: PubMed
Tipo: Artigo de Revista Científica
Publicado em /06/1991 Português
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Surface exposure of the O1 serotype lipopolysaccharide in encapsulated Klebsiella pneumoniae strains belonging to different serotypes was examined by using the O1 antigen-specific bacteriophages FC3-1 and FC3-2 in conjunction with immunogold electron microscopy and enzyme immunoassays with specific antisera. Despite the presence of the capsular polysaccharide, the O1 antigen was exposed at the cell surface in strains producing K2, K7, K8, K12, K19, K21, K22, K34, K35, K42, K45, K55, K57, K62, K66, K69, and K70 capsular polysaccharides. However, in strains producing K1, K10, and K16 capsular polysaccharides, the O1 antigen was masked by the K antigen. These results suggest that, since the O1 antigen is surface exposed in many different strains of K. pneumoniae with different capsular serotypes and is also able to immunoprotect, its potential as a useful vaccine component should not be overlooked.

Separation of phenotypes in mutant alleles of the Schizosaccharomyces pombe cell-cycle checkpoint gene rad1+.

Kanter-Smoler, G; Knudsen, K E; Jimenez, G; Sunnerhagen, P; Subramani, S
Fonte: PubMed Publicador: PubMed
Tipo: Artigo de Revista Científica
Publicado em /12/1995 Português
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17.69%
The Schizosaccharomyces pombe rad1+ gene is involved in the G2 DNA damage cell-cycle checkpoint and in coupling mitosis to completed DNA replication. It is also required for viability when the cdc17 (DNA ligase) or wee1 proteins are inactivated. We have introduced mutations into the coding regions of rad1+ by site-directed mutagenesis. The effects of these mutations on the DNA damage and DNA replication checkpoints have been analyzed, as well as their associated phenotypes in a cdc17-K42 or a wee1-50 background. For all alleles, the resistance to radiation or hydroxyurea correlates well with the degree of functioning of checkpoint pathways activated by these treatments. One mutation, rad1-S3, completely abolishes the DNA replication checkpoint while partially retaining the DNA damage checkpoint. As single mutants, the rad1-S1, rad1-S2, rad1-S5, and rad1-S6 alleles have a wild-type phenotype with respect to radiation sensitivity and checkpoint functions; however, like the rad1 null allele, the rad1-S1 and rad1-S2 alleles exhibit synthetic lethality at the restrictive temperature with the cdc17-K42 or the wee1-50 mutation. The rad1-S5 and rad1-S6 alleles allow growth at higher temperatures in a cdc17-K42 or wee1-50 background than does wild-type rad1+...

THE USE OF K42 OR P32 LABELED ERYTHROCYTES AND I131 TAGGED HUMAN SERUM ALBUMIN IN SIMULTANEOUS BLOOD VOLUME DETERMINATIONS 1

Berson, Solomon A.; Yalow, Rosalyn S.
Fonte: PubMed Publicador: PubMed
Tipo: Artigo de Revista Científica
Publicado em /06/1952 Português
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16.71%

Comparison of the Uptake of P32 and K42 by Intact Alfalfa and Oat Roots 123

Lambert, Roger G.; Linck, A. J.
Fonte: PubMed Publicador: PubMed
Tipo: Artigo de Revista Científica
Publicado em /11/1964 Português
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16.71%

Histone transcription in cell cycle mutants of fission yeast

Matsumoto, Seiji; Yanagida, Mitsuhiro; Nurse, Paul
Fonte: PubMed Publicador: PubMed
Tipo: Artigo de Revista Científica
Publicado em /04/1987 Português
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16.71%
The level of histone H2B transcripts peak during S-phase of the fission yeast Schizosaccharomyces pombe. The pattern of transcript accumulation has been monitored in temperature-sensitive mutants which block at different times during the cell cycle, at start in G1 where the cell becomes committed to the mitotic cycle, in G1 after start, and during S-phase. Cells blocked before start using cdc10-129 do not accumulate histone H2B transcripts, but cells blocked after start using cdc22-C11 do show accumulation. Transcript levels increase in another mutant cdc20-M10 which also blocks in G1. These experiments establish that histone H2B transcripts increase in level in preparation for S-phase during late G1 before any DNA synthesis. Passage of start begins a sequence of events leading to S-phase which includes an increase in histone H2B transcript levels. In the cdc20 and cdc22 mutants transcript levels do not decrease normally suggesting that the signals which lead to the fall in level are not given in these G1-arrested cells. The mutants cdc17-K42 (defective in DNA ligase) and cdc24-M38 block in late S-phase after the DNA content has doubled. Histone H2B transcripts increase normally but remain at a high level. In these mutants even though DNA content has doubled...

Day-night Differences in the Accumulation and Translocation of Ions by Tobacco Plants 1

Wallace, A.; Soufi, S. M.; Hemaidan, N.
Fonte: PubMed Publicador: PubMed
Tipo: Artigo de Revista Científica
Publicado em /01/1966 Português
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16.71%
More K42, Rb86, and Br82 was accumulated by intact tobacco plants and root systems from detopped plants during the night than during the day when studies for both periods were made in dark rooms controlled at 18°. More, however, was translocated to shoots during the day than during the night in intact plants. This latter effect parallels the periodicity of exudation in root systems from detopped plants.

A Small Conserved Surface in SUMO Is the Critical Structural Determinant of Its Transcriptional Inhibitory Properties

Chupreta, Sergey; Holmstrom, Sam; Subramanian, Lalitha; Iñiguez-Lluhí, Jorge A.
Fonte: American Society for Microbiology Publicador: American Society for Microbiology
Tipo: Artigo de Revista Científica
Publicado em /05/2005 Português
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16.71%
Small ubiquitin-like modifier (SUMO) modification of sequence-specific transcription factors has profound regulatory consequences. By providing an intrinsic inhibitory function, SUMO isoforms can suppress transcriptional activation, particularly at promoters harboring multiple response elements. Through a comprehensive structure-function analysis, we have identified a single critical sector along the second beta sheet and the following alpha helix of SUMO2. This distinct surface is defined by four basic residues (K33, K35, K42, R50) that surround a shallow pocket lined by aliphatic (V30, I34) and polar (T38) residues. Substitutions within this area specifically and dramatically affected the ability of both SUMO2 and SUMO1 to inhibit transcription and revealed that the positively charged nature of the key basic residues is the main feature responsible for their functional role. This highly conserved surface accounts for the inhibitory properties of SUMO on multiple transcription factors and promoter contexts and likely defines the interaction surface for the corepressors that mediate the inhibitory properties of SUMO.

Sodium and Potassium Ion Effluxes from Squid Axons under Voltage Clamp Conditions

Mullins, L. J.; Adelman, W. J.; Sjodin, R. A.
Fonte: PubMed Publicador: PubMed
Tipo: Artigo de Revista Científica
Publicado em /05/1962 Português
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Squid giant axons loaded with Na24 were subjected to short duration (0.5 msec.) clamped depolarizations of about 100 mv at frequencies of 20/sec. and 60/sec. while in choline sea water. Under such conditions the early outward current was just about maximal at the time of termination of the clamping pulse. An integration of the early current versus time record gave 1.2 μcoulomb/cm2 pulse, while a measurement of the extra Na24 efflux resulting from repetitive pulsing gave a charge transfer of 1.4 μcoulomb/cm2 pulse. In sodium-containing sea water and with pulses 50-75 mv more positive than ENa the Na24 efflux is about 3 times the measured charge transfer. The efflux of K42 from a previously loaded axon into normal sea water is only 50 per cent of the measured charge transfer when the membrane is held for about 5 msec. at a potential such that there is no early current, and such pulses are at 10-20/sec. The experiments appear to confirm the suggestion that the early current during bioelectric activity is sodium but provide unsatisfactory support for the identification of the delayed but sustained current solely with potassium ions. Resting Na+ efflux is 0.6 pmole/cm2 sec. mmole [Na]1, while the apparent K+ efflux is about 250 pmole/cm2 sec. and is little affected by hyperpolarization.

NXP-2 association with SUMO-2 depends on lysines required for transcriptional repression

Rosendorff, Adam; Sakakibara, Shuhei; Lu, Sixin; Kieff, Elliott; Xuan, Yan; DiBacco, Alessandra; Shi, Yujiang; Shi, Yang; Gill, Grace
Fonte: National Academy of Sciences Publicador: National Academy of Sciences
Tipo: Artigo de Revista Científica
Português
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16.71%
Small ubiquitin-like modifier (SUMO) modification of transcription factors is generally associated with repression. Reverse genetic analysis of SUMO-1, and -2 conserved residues emphasized the importance of dual charge reversals in abrogating the critical role of SUMO-2 K33, K35, and K42 in repression. GST-SUMO-2-affinity chromatography followed by liquid chromatography (LC)-MS analysis identified proteins that appeared to bind preferentially to WT SUMO-2 versus SUMO-2 K33E and K35E. LSD1, NXP-2, KIAA0809 (ARIP4), SAE2, RanGAP1, PELP1, and SETDB1 bound to SUMO-2 and not to SUMO-2 K33E, K42E, or K35E and K42E. Although LSD1 is a histone lysine demethylase, and histone H3K4 was demethylated at a SUMO-2-repressed promoter, neither overexpression of a dominant-negative LSD1 nor LSD1 depletion with RNA interference affected SUMO-2-mediated repression, indicating that LSD1 is not essential for repression, in this context. When tethered to a promoter by fusion to Gal4, NXP-2 repressed transcription, consistent with a role for NXP-2 in SUMO-mediated repression. SUMO-2-associated proteins identified in this study may contribute to SUMO-dependent regulation of transcription or other processes.

POTASSIUM TRANSPORT IN HUMAN ERYTHROCYTES: EVIDENCE FOR A THREE COMPARTMENT SYSTEM

Solomon, A. K.; Gold, G. Lennard
Fonte: The Rockefeller University Press Publicador: The Rockefeller University Press
Tipo: Artigo de Revista Científica
Publicado em 20/01/1955 Português
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17.9%
Whole human blood is incubated for periods of ½ to 3 hours with K42 at 37°C. At the close of this period, called pre-incubation, the plasma is removed from the cells and the cells, now become radioactive, are again incubated in a mixture of plasma and buffer for periods of up to 10 additional hours. The time course of the K42 activity of the incubating medium is followed. Characteristically, after 2 hours of pre-incubation, the activity in the medium rises to a peak about 1 and ½ hours after resuspension, and then falls slowly until at 10 hours it is very close to its initial value at the beginning of the resuspension interval. This transient rise in K42 activity in the medium is taken to indicate that the red cell does not consist of a single uniform K compartment, but contains at least two compartments. Thus one cellular compartment contains a reservoir of high specific activity K which provides the specific activity gradient necessary to drive the K42 content of the medium to its transient peak. Experiments with Na indicate that its behavior in this respect is unlike that of K. The experimental data are matched to a simple model system which is capable of theoretical analysis with the aid of an analogue computer. The model system...

Draft Genome of Streptomyces zinciresistens K42, a Novel Metal-Resistant Species Isolated from Copper-Zinc Mine Tailings

Lin, Yanbing; Hao, Xiuli; Johnstone, Laurel; Miller, Susan J.; Baltrus, David A.; Rensing, Christopher; Wei, Gehong
Fonte: American Society for Microbiology Publicador: American Society for Microbiology
Tipo: Artigo de Revista Científica
Publicado em /11/2011 Português
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27.35%
A draft genome sequence of Streptomyces zinciresistens K42, a novel Streptomyces species displaying a high level of resistance to zinc and cadmium, is presented here. The genome contains a large number of genes encoding proteins predicted to be involved in conferring metal resistance. Many of these genes appear to have been acquired through horizontal gene transfer.

The Sodium and Potassium Exchange between Intact Frogs and Their Environment

STEINBACH, H. BURR
Fonte: The Rockefeller University Press Publicador: The Rockefeller University Press
Tipo: Artigo de Revista Científica
Publicado em 01/07/1966 Português
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17.69%
Intact living frogs (Rana pipiens) were partially immersed in dilute salt solution labeled with K42 or Na24 or, alternatively, injected with Ringer’s fluid containing the appropriate isotope and then partially immersed in unlabeled dilute salt. Before isotopic equilibrium, the animals were sacrificed and specific activities of K42 and Na24 were determined for medium, skin, plasma, and other tissues. With Na24, entering from the medium or escaping to the medium, specific activities of the skin approach that of the plasma. For K42, entering from the medium, the specific activity exceeds that of the plasma. The results are interpreted as indicating that the exchange rate for Na is greater plasma to skin than medium to skin, with the reverse situation for K. Values are given for average Na, K, and Cl contents of the various organ systems.

The Efflux of Substances from Frog Ventricles to Sucrose and to Ringer's Solutions

Van Der Kloot, William G.; Dane, Benjamin
Fonte: The Rockefeller University Press Publicador: The Rockefeller University Press
Tipo: Artigo de Revista Científica
Publicado em 01/11/1964 Português
Relevância na Pesquisa
17.35%
The frog ventricle in sucrose solution contracts for several hours at 25°C, and for as long as 24 hours at 5°G. The possibility that a fraction of the extracellular fluid remains outside of the excitable membrane was examined by measuring the efflux of tracers. The half-time for the efflux to sucrose solution at 25°C of C14 sucrose is about 1 minute, for Na24 is 6.5 minutes, and for Cl86 is 4 minutes. There is no evidence for the retention of an extracellular Na fraction. The Q10 for Na and Cl efflux is about 1.3. The half-time for K42 efflux is about 180 minutes; the Q10 is 1.7. The efflux rates of Na24, Cl36 and K42 to sucrose and to Ringer's solutions are quite similar. Ca45 efflux is only one-fifth as fast to sucrose solution as to Ringer's; the retention of Ca++ may be important for maintaining excitability in sucrose solution. P32 efflux is five times faster to sucrose solution than to Ringer's solution, and there is a similar increase in the rate of inosine loss to sucrose solution. The Q10 for efflux to sucrose solution is 2.2 for P32O4 and 2.4 for inosine. We suggest that energy metabolism is abnormal in ventricles in sucrose solution and that low temperature prolongs excitability by slowing the metabolic change.

Potassium Fluxes in Desheathed Frog Sciatic Nerve

Hurlbut, William P.
Fonte: The Rockefeller University Press Publicador: The Rockefeller University Press
Tipo: Artigo de Revista Científica
Publicado em 01/07/1963 Português
Relevância na Pesquisa
17.35%
Desheathed frog (R. pipiens) sciatic nerves were soaked in Na-deficient solutions, and measurements were made of their Na and K contents and of the movements of K42. When a nerve is in Ringer's solution, the Na fluxes are equal to the K fluxes, and about 75 per cent of the K influx is due to active transport. The Na content and the Na efflux are linearly related to the Na concentration of the bathing solution, while the K content and the K fluxes are not so related. When a nerve is in a solution in which 75 per cent of the NaCl has been replaced by choline chloride or sucrose, the active K influx exceeds the active Na efflux, and the K content is maintained. When a nerve is soaked in a solution that contains Li, the K42 uptake is inhibited, and the nerve loses K and gains Li. When a Li-loaded nerve recovers in a Li-free solution, K is taken up in exchange for Li. This uptake of K requires Na in the external solution. It is concluded that the active transports of K and of Na may be due to different processes, that an accumulation of K occurs only in exchange for an intracellular cation, which need not be Na, and that Na plays a specific, but unknown, role in K transport.

Tracer and Non-Tracer Potassium Fluxes in Frog Sartorius Muscle and the Kinetics of Net Potassium Movement

Sjodin, R. A.; Henderson, E. G.
Fonte: The Rockefeller University Press Publicador: The Rockefeller University Press
Tipo: Artigo de Revista Científica
Publicado em 01/03/1964 Português
Relevância na Pesquisa
17.9%
Experiments were performed to test the applicability of permeability kinetics to whole frog sartorius muscle using K42 ions as tracers of potassium flux. The whole muscle was found to obey closely the kinetic laws expected to hold for single cellular units in which the potassium fluxes are membrane-limited and intracellular mixing is rapid enough not to introduce serious error. In a 5 mM K Ringer's solution, potassium efflux was very nearly equal to influx when the rate constant for K42 loss was applied to the whole of the muscle potassium. Over a fairly wide range of external potassium concentration, the assumed unidirectional fluxes measured with tracer K42 showed good agreement with net potassium changes determined analytically. The specific activity of potassium lost from labeled muscles to an initially K-free Ringer's solution was measured as a test of the adequacy of intracellular mixing. The results were those expected for a population of cells with uniformly distributed intracellular K42. A small deviation was encountered which can be attributed either to a dispersion of fiber sizes in the sartorius or to a possible small additional cellular compartment in each individual fiber. The additional cellular compartment, should it exist...