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68372. The Permostridulidae fam. n. (Panorthoptera), a new enigmatic insect family from the Upper Permian of France
- Creator:
- Béthoux, Olivier, Nel, André, Lapeyrie, Jean, and Gand, Georges
- Type:
- article, model:article, and TEXT
- Subject:
- Insecta, Neoptera, Panorthoptera, Permostridulidae fam. n., Permostridulus brongniarti gen. n. & sp. n., Upper Permian, France, and stridulatory apparatus
- Language:
- English
- Description:
- The unusual wing characters of the Permian insect Permostridulus brongniarti gen. n., sp. n. justifies the creation of a new family, the Permostridulidae fam. n., within the Panorthoptera. Phylogenetic relationships with the extinct order Caloneurodea, related to the Orthoptera (crickets, grasshoppers), are assumed. This assumption suggests an occurrence of the Permostridulidae at least since the Upper Carboniferous. The most prominent feature of the wing venation is a stridulatory apparatus, nonhomologous with those previously known in "panorthopterid" lineages. This is the oldest recorded sound-producing device of an animal.
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
68373. The peroxidase activity of cytochrome b6f complex from spinach chloroplasts
- Creator:
- Chen, X. B., Hou, C., Li, L. B., and Kuang, T. Y.
- Format:
- bez média and svazek
- Type:
- model:article and TEXT
- Subject:
- botanika, botany, cytochrome b6f complex, guaiacol, heme-containing protein, hydrogen peroxide, and peroxidase activity
- Language:
- Multiple languages
- Description:
- The cytochrome b6f (Cyt b6f) complex, which functions as a plastoquinol-plastocyanin oxidoreductase and mediates the linear electron flow between photosystem II (PSII) and photosystem I (PSI) and the cyclic electron flow around PSI, was isolated from spinach (Spinacia oleracea L.) chloroplasts using n-octyl-β-D-glucopyranoside (β-OG). The preparation was also able to catalyze the peroxidase-like reaction in the presence of hydrogen peroxide (H2O2) and guaiacol. The optimal conditions for peroxidase activity of the preparation included: pH 3.6, ionic strength 0.1, and temperature 35°C. The apparent Michaelis constant (Km) values for H2O2 and guaiacol were 50 mM and 2 mM, respectively. The bimolecular rate constant (k obs) was about 26 M-1 s-1 and the turnover number (K cat) was about 60 min-1 (20 mM guaiacol, 100 mM sodium phosphate, pH 3.6, 25°C, [H2O2]<100mM). These parameters were similar to those of several other heme-containing proteins, such as myoglobin and Cyt c. and X. B. Chen ... [et al.].
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
68374. The persistent Bond of socialism
- Creator:
- Chalupecký, Petr and Mareš, Jiří
- Format:
- bez média and svazek
- Type:
- model:article and TEXT
- Language:
- English
- Description:
- Přeložil Jiří Mareš
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
68375. The person at law from the point of view of pure legal science
- Creator:
- Beran, Karel
- Type:
- article, model:article, and TEXT
- Subject:
- person, personified set of legal norms, point of assignability, pure legal science, and legal normativism
- Language:
- English
- Description:
- The person as a legal term is traditionally derived from a human being, either from an individual or a group of people. Hans Kelsen maintains that no such substance really exists. “The person exists only insofaras he “has” duties and rights; apart from them the person has no existence whatsoever.” This is why a human being is construed as an abstract holder of subjective rights rather than the person in a legal sense. This conception results in the normative construction of a person. The person is considered to be a mere point, an ideal and never real fact. Kelsen designates this point as “personification of the set of norms” regulating the conduct of a human being. However, such an entity as the personification of legal norms does not exist in the outer, real world. The legal order may attach legal personality to any segment of the outer world, even to an imagination of something non-existent in the outer world. The relationship between this abstract point and the addressee of duties is called “assignability”. This is why the person in a legal sense is, in the normativist perspective, considered to be “a point of assignability”. The aim of this article is to describe the approach of pure legal science to a person as a personified set of legal norms or as a point of assignability.
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
68376. The personite problem and the stage-theoretic reply
- Creator:
- Noonan, Harold
- Format:
- bez média and svazek
- Type:
- model:article and TEXT
- Subject:
- personites, perdurance, stage-theory, moral status, and Johnston
- Language:
- Slovak
- Description:
- Personites are shorter-lived, person-like things that extend across part of a person’s life. Their existence follows from the standard perdurance view of persons. Johnston argues that it has bizarre moral consequences. For example, it renders morally problematic spending time learning a difficult language in anticipation of going abroad. The crucial thought is that if persons have moral status so do personites. Johnston argues for this claim. Kaiserman responds, on behalf of stage theory, that this only works on a perdurantist account. This is a conservative response to the problem. It seeks to show that retaining the ontology of perdurantism one can resolve the difficulty by a semantic change. I show that the personite problem can be reworked as an argument against stage theorists. The stage theorist can respond by rejecting an assumption of the reasoning. But if it is acceptable for him to do so the perdurantist can reject this assumption too, which is enough by itself to block Johnston’s argument. Thus, for all it helps with the personite problem, stage theorists might as well be perdurantists.
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
68377. The pH-dependent and enzymatic release of cytarabine from hydrophilic polymer conjugates
- Creator:
- Pola, R., Olga Janoušková, and Tomáš Etrych
- Format:
- print, bez média, and svazek
- Type:
- article, články, model:article, and TEXT
- Subject:
- Fyziologie člověka a srovnávací fyziologie, fyziologie, physiology, HPMA copolymers, drug delivery system, nucleoside analogues, cytarabine, 14, and 612
- Language:
- English
- Description:
- Cytarabine is one of the most efficient drugs in the treatment of hematological malignancies. In this work, we describe the synthesis and characterization of two different polymer conjugates of cytarabine that were designed for the controlled release of cytarabine within the leukemia cells. Reactive copolymers of N-(2-hydroxypropyl)methacrylamide (HPMA) and 3-(3-methacrylamidopropanoyl)thiazolidine-2-thione) or 3-(Nmethacryloylglycyl- phenylalanylleucylglycyl)thiazolidine-2-thione were used in the study as reactive polymer precursors for reaction with cytarabine. The enzymatic release of cytarabine from the conjugate containing a GFLG spacer utilizing cathepsin B was verified. In addition to enzymolysis, the pH-dependent hydrolysis of cytarabine from both copolymers was also confirmed. Approximately 40 % and 20 % of the drug was released by spontaneous hydrolysis at pH 7.4 within 72 h from the polymer conjugates with the GFLG and β-Ala spacers, respectively. At pH 6.0, the spontaneous hydrolysis slowed down, and less than 10 % of the drug was liberated within 72 h. The results of the cytotoxicity evaluation of the polymer conjugates in vitro against various cell lines showed that the cytotoxicity of the polymer conjugates is approximately three times lower in comparison to free cytarabine., R. Pola, O. Janoušková, T. Etrych., and Obsahuje bibliografii
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
68378. The phenotypic patterns of essential hypertension are the key to identifying "high blood pressure" genes
- Creator:
- Paul I. Korner
- Format:
- print, bez média, and svazek
- Type:
- article, články, model:article, and TEXT
- Subject:
- Fyziologie člověka a srovnávací fyziologie, stres (fyziologie), obezita, stress (physiology), obesity, genotype-phenotype relationship, integrative biology, Neural and non-neural mechanisms, high salt, systems analysis and phenotype, 14, and 612
- Language:
- English
- Description:
- a1_The genes that cause or increase susceptibility to essential hypertension (EH) and related an imal models remain unknown. Their identification is unlikely to be realized with current genetic approaches, because of ambiguities in the genotype-phenotype relationships in these polygenic disorders. In turn, the phenotype is not just an aggregate of traits, but needs to be related to specific components of the circulatory control system at different stages of EH. Hence, clues about important genes must come through the phenotype, reversing the order of current approaches. A recent systems analysis has highlighted major differences in circulatory control in the two main syndromes of EH: 1) stress-and-salt-related EH (SSR-EH) - a constrictor hypertension with low blood volume; 2) hypertensive obesity - SSR-EH plus obesity. Each is initiated through sensitization of central synapses linking the cerebral cortex to the hypothalamic defense area. Several mechanis ms are probably involved, including cerebellar effects on baroreflexes. The result is a sustained increase in sympathetic neural activity at stimulus levels that have no effect in normal subjects. Subsequent progression of EH is largely thro ugh interactions with non-neural mechanisms, including changes in concentration of vascular autacoids (e.g. nitric oxide) and the amplifying effect of structural changes in large resistance vessels. The rising vasoconstriction increases heterogeneity of blood flow, causing rarefaction (decreased microvascular densit y) and deterioration of vital organs. SSR-EH also increases food intake in response to stress, but only 40% of these individual s develop hypertensive obesity. Their brain ignores the adiposity signals that normally reduce eating., a2_Hyperinsulinemia masks the sympathetic vasoconstriction through its dilator action, rais es blood volume, whilst renal nephropathy and other diabetic complications are common. In each syndrome the neural and non-neural determinants of hypertension provide targets fo r identifying high BP genes. Reading the genome from the phenotype will require new approaches, such as those used in developmental genetics. In addition, transgenic technology may help verify hypotheses and examine whether an observed effect is through single or multiple mechanisms. To obtain answers will require substantial collaborative efforts between physiologists and geneticists., P. I. Korner., and Obsahuje bibliografii
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
68379. The pheromone verbenone and its function in Dendroctonus armandi (Coleoptera: Curculionidae: Scolytinae)
- Creator:
- Zhao, Mingzhen, Dai, Lulu, Sun, Yaya, Fu, Danyang, and Chen, Hui
- Format:
- print, počítač, and online zdroj
- Type:
- article, články, journal articles, model:article, and TEXT
- Subject:
- Zoologie, polní pokusy, field trials, Coleoptera, Curculionidae, Dendroctonus armandi, trans-verbenol, verbenone, electrophysiological (EAG), olfactory assays (Y-tube assays), 2, and 59
- Language:
- English
- Description:
- The Chinese white pine beetle, Dendroctonus armandi Tsai and Li is a native species of bark beetle and one of the most destructive in much of western China. Little is known about the characterization of the pheromones trans-verbenol and verbenone, and their functions in D. armandi are unknown. Electroantennogram tests (EAG) and olfactory assays (Y-tube assays) in the laboratory revealed that (1) trans-verbenol may be an anti-aggregation pheromone for male and an aggregation pheromone for female D. armandi and (2) female beetles are more attracted to controls (hexane) than low concentrations of verbenone and male beetles more attracted to controls than high concentrations of verbenone. Field trials indicated that the addition of verbenone to bait used to trap D. armandi remarkably decreased the efficiency of field trapping. These results indicate that verbenone is an anti-aggregation pheromone for male D. armandi. This research provides evidence of the role of verbenone among the different types of pheromones. The pheromone verbenone clearly could be used to protect healthy Chinese white pines., Mingzhen Zhao, Lulu Dai, Yaya Sun, Danyang Fu, Hui Chen., and Obsahuje bibliografii
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
68380. The philosophy of Ecological Leninism
- Creator:
- Knowlton Jr., Kenny and Gamble, Cameron
- Format:
- bez média and svazek
- Type:
- model:article and TEXT
- Subject:
- dialectical materialism, ecological Leninism, metabolic rift theory, Marxism, political ecology, and dialectics
- Language:
- Czech
- Description:
- Recently, the term “Ecological Leninism” has emerged as a popular invocation in the works of Marxist thinkers attempting to grasp dialectically the numerous intersecting ecological crises. Yet, beyond a few introductory remarks, little has been said about the content of this concept and, even less, its relation to Lenin. Generally, the concept attempts to combine Leninist political theory with the ecological analyses of the growing number of ecosocialists and eco-Marxists working both within the academy and without. This paper intends an initial, philosophical contribution toward developing Ecological Leninism: (1) by providing an interpretation of Lenin’s philosophical method, that is, dialectical and historical materialism; and (2) explicating the way in which this philosophy gives rise to a political ecological theory and practice, Ecological Leninism, that addresses the crisis of the metabolic rift between nature and society. We intend to contribute to the development of Ecological Leninism by clarifying the philosophy through which the political method is articulated. Thus, we hope to show that, under the conditions of a global metabolic rift produced by capitalist society, Ecological Leninism as a political ecological theory signals the possibility of securing a just and sustainable world for future generations.
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public