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11403. What drives conditional cooperation in public goods games?

Creator:
Katuščák, Peter and Miklánek, Tomáš
Publisher:
CERGE-EI
Format:
electronic, bez média, svazek, and 34 stran : ilustrace, tabulky.
Type:
model:monograph and TEXT
Subject:
Ekonomie, dobročinnost, fundraising, experimentální ekonomie, charity, fund raising, experimental economics, 177.72, 364-646.3, 33-028.77, (048.8), 4, and 33
Language:
English and Czech
Description:
Peter Katuščák, Tomáš Miklánek., Obsahuje bibliografii a bibliografické odkazy, and České a anglické resumé
Rights:
http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public

11404. What is the role of neurotransmitter systems in cortical seizures?

Creator:
Pavel Mareš and Hana Kubová
Format:
print, bez média, and svazek
Type:
article, články, model:article, and TEXT
Subject:
Fyziologie člověka a srovnávací fyziologie, neurofyziologie, epileptologie, farmakologie, neurophysiology, epileptology, pharmacology, cortical epileptic afterdischarges, GABA, glutamate, immature rats, 14, and 612
Language:
English
Description:
Epileptic afterdischarges (ADs) elicited by electrical stimulation of sensorimotor cortical area were used as a model to study the role of neurotransmitter systems in cortical seizures in three age groups of developing rats. Drugs augmenting inhibition mediated by GABAA receptors were found to suppress ADs in all age groups, their activity was usually more marked in younger than in 25-day-old rat pups. Drugs potentiating GABAB receptors exhibit lower efficacy and more complicated developmental profile than GABAA-ergic drugs. Effects of an antagonist of GABAB receptor – marked prolongation of ADs in all three age groups – suggest an important role of GABAB receptors in arrest of cortical seizures. Drugs affecting glutamate receptors exhibit variable effects, usually better expressed in older animals than in 12-day-old ones. No specific role for ionotropic as well as metabotropic glutamate receptors could be predicted. Activation of adenosinergic inhibitory modulatory system also exhibited anticonvulsant action in the present model. All three neurotransmitter systems probably participate in mechanisms of generation, maintenance and arrest of cortical seizures., P. Mareš, H. Kubová., and Obsahuje bibliografii a bibliografické odkazy
Rights:
http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public

11405. What is the role of subcutaneous single injections on the behavior of adult male rats exposed to drugs?

Creator:
Šlamberová, R., Nohejlová, K., Ochozková, A., and Mihalčíková, L.
Format:
bez média and svazek
Type:
model:article and TEXT
Subject:
amphetamine, MDMA, cocaine, THC, behavior, LABORAS test • Injection, and injection
Language:
English
Description:
Psychostimulants, as well as cannabinoids, have been shown to significantly affect a great variety of behaviors in both humans and laboratory animals. Our previous studies have repeatedly demonstrated that the application of the vehicle for psychostimulants, i.e. saline, to control groups, generated different behavioral test results compared to absolute naïve controls (i.e. without any injection). Therefore, our present study has set three goals: (1) to evaluate the effect of three different psychostimulant drugs, (2) to evaluate the effect of three doses of delta 9-tetrahydrocannabinol (THC), and (3) to evaluate the effect of saline and ethanol injections vs sham injections and no injection on spontaneous behavior of adult male rats. The LABORAS test (Metris B.V., Netherlands) was used to examine spontaneous locomotor activity and exploratory behavior in an unknown environment over 1 h. In Experiment 1, psychostimulant drugs were tested: single subcutaneous (s.c.) injections of amphetamine (5 mg/kg), cocaine (5 mg/kg), and 3,4-methylenedioxymethamphetamine (MDMA) (5 mg/kg) were applied prior to testing. Control animals received the same volume (1 ml/kg) of s.c. saline. In Experiment 2, the effect of three doses of THC (1, 2, and 5 mg/kg, s.c.) were examined. An s.c. injection of vehicle (ethanol) was used as a control. In Experiment 3, injections of saline and ethanol were compared to the group receiving a sham s.c. injection and to a group of absolute “naïve” controls. Our results demonstrated that (1) all psychostimulants increased locomotion time, distance traveled, and speed while decreasing immobility time of adult male rats relative to saline controls. The most prominent effect was associated with MDMA; (2) The effect of THC was dosedependent and was most apparent within the first 10 min of the LABORAS test. (3) With regard to the effect of injection: absolute controls (without injection) compared to animals injected with ethanol, saline, or sham-injected displayed reduced immobility time, traveled longer distances, and had increased speed. In conclusion, our data showed drug dependent behavioral changes in adult male rats after application of psychostimulants and cannabinoids. Our findings also suggest that not only drugs but the actual single injection per se also affects the behavior of laboratory animals in an unknown environment. This effect seems to be associated with the acute stress associated with the injection.
Rights:
http://creativecommons.org/publicdomain/mark/1.0/ and policy:public

11406. What is the source of free radicals causing hemolysis in stored blood?

Creator:
Jaroslav Racek, Růžena Herynková, Václav Holeček, Faltysová, J., and Krejčová, I.
Format:
print, bez média, and svazek
Type:
article, články, model:article, and TEXT
Subject:
Fyziologie člověka a srovnávací fyziologie, volné radikály, leukocyty, hemolýza, free radicals, leucocytes, hemolysis, 14, and 612
Language:
English
Description:
The quality of stored blood can be deteriorated by hemolysis caused by free radicals. The purpose of this study was to elucidate whether neutrophile leukocytes are the source of free radicals in stored blood as in hemodialyzed patients. Resuspensions with low (LL) or high (HL) leukocyte concentrations were prepared from samples of twenty healthy volunteers. The samples were incubated for 10 days at 4 °C and then for one day at 37 °C. Markers of hemolysis and free radical metabolism were examined before and after incubation in LL and HL samples. In spite of the difference of leukocytes counts in LL and HL resuspensions (p<0.0001), the pre-incubation values of all laboratory parameters were practically identical. In post-storage samples, superoxide dismutase and glutathione peroxidase activities did not differ in either group. Reduced glutathione in erythrocytes and extracellular antioxidant capacity were insignificantly lower in HL resuspensions, but the increase of malondialdehyde was much more pronounced in the HL samples (p<0.0001). The degree of hemolysis, expressed as the extracellular increase of potassium (p<0.001), hemoglobin (p<0.05) and lactate dehydrogenase (p<0.05), was higher in the HL samples. Our results support the hypothesis that leukocytes participate in free radical production in stored blood., J. Racek, R. Herynková, V. Holeček, J. Faltysová, I. Krejčová., and Obsahuje bibliografii
Rights:
http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public

11407. What's in a name in a war

Creator:
Jurajda, Štěpán and Kovač, Dejan
Publisher:
CERGE-EI
Format:
electronic, bez média, svazek, and 44 stran : ilustrace, tabulky, mapy.
Type:
model:monograph and TEXT
Subject:
Sociologie, 20. století, nacionalismus, rodná jména, sociální paměť, mezigenerační vztahy, ustašovci, jugoslávská válka (1991-1995), sociolingvistika, nationalism, first names, social memory, intergenerational relations, Ustashi, Yugoslav War (1991-1995), sociolinguistics, Chorvatsko, Croatia, 172.15, 81'373.231, 316.6:159.953, 316.4.051.63, 329.18(497.5)-051, 355.48(497.1)"1991/1995", 81'27, (497.5), (048.8), 18, and 316
Language:
English and Czech
Description:
Štěpán Jurajda, Dejan Kovač., Obsahuje bibliografii a bibliografické odkazy, and České a anglické resumé
Rights:
http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public

11408. What’s the price of a nonmeasurable set?

Creator:
Sardella, Mirko and Ziliotti, Guido
Format:
bez média and svazek
Type:
model:article and TEXT
Subject:
Lebesgue measure, nonmeasurable set, and axiom of choice
Language:
English
Description:
In this note, we prove that the countable compactness of {0, 1} R together with the Countable Axiom of Choice yields the existence of a nonmeasurable subset of . This is done by providing a family of nonmeasurable subsets of whose intersection with every non-negligible Lebesgue measurable set is still not Lebesgue measurable. We develop this note in three sections: the first presents the main result, the second recalls known results concerning non-Lebesgue measurability and its relations with the Axiom of Choice, the third is devoted to the proofs.
Rights:
http://creativecommons.org/publicdomain/mark/1.0/ and policy:public

11409. When does the inverse have the same sign pattern as the transpose?

Creator:
Eschenbach, Carolyn A., Hall, Frank J., Harrell, Deborah L., and Li, Zhongshan
Format:
bez média and svazek
Type:
model:article and TEXT
Subject:
math and sign pattern
Language:
English
Description:
By a sign pattern (matrix) we mean an array whose entries are from the set $\lbrace +,-,0\rbrace $. The sign patterns $A$ for which every real matrix with sign pattern $A$ has the property that its inverse has sign pattern $A^T$ are characterized. Sign patterns $A$ for which some real matrix with sign pattern $A$ has that property are investigated. Some fundamental results as well as constructions concerning such sign pattern matrices are provided. The relation between these sign patterns and the sign patterns of orthogonal matrices is examined.
Rights:
http://creativecommons.org/publicdomain/mark/1.0/ and policy:public

11410. When spectra of lattices of z-ideals are Stone-Čech compactifications

Creator:
Dube, Themba
Format:
bez média and svazek
Type:
model:article and TEXT
Subject:
completely regular frame, coherent frame, z-ideal, d-ideal, Stone-Čech compactification, and booleanization
Language:
English
Description:
Let X be a completely regular Hausdorff space and, as usual, let C(X) denote the ring of real-valued continuous functions on X. The lattice of z-ideals of C(X) has been shown by Martínez and Zenk (2005) to be a frame. We show that the spectrum of this lattice is (homeomorphic to) βX precisely when X is a P-space. This we actually show to be true not only in spaces, but in locales as well. Recall that an ideal of a commutative ring is called a d-ideal if whenever two elements have the same annihilator and one of the elements belongs to the ideal, then so does the other. We characterize when the spectrum of the lattice of d-ideals of C(X) is the Stone-Čech compactification of the largest dense sublocale of the locale determined by X. It is precisely when the closure of every open set of X is the closure of some cozero-set of X.
Rights:
http://creativecommons.org/publicdomain/mark/1.0/ and policy:public

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