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68362. The paradox of 1968
- Creator:
- Šrubař, Ilja
- Format:
- bez média and svazek
- Type:
- model:article and TEXT
- Language:
- Czech
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
68363. The paradox of moralistic fallacy: a case against the dangerous knowledge
- Creator:
- Ondráček, Tomáš
- Format:
- bez média and svazek
- Type:
- model:article and TEXT
- Subject:
- moralistic fallacy, reverse naturalistic fallacy, Bernard D. Davis, paradox of moralistic fallacy, dangerous knowledge, moralistický omyl, reverzní naturalistický omyl, paradox moralistického omylu, and nebezpečná znalost
- Language:
- Czech
- Description:
- In this article, the concept of moralistic fallacy introduced by B. D. Davis is elaborated on in more detail. Th e main features of this fallacy are discussed, and its general form is presented. Th e moralistic fallacy might have some undesirable outcomes. Some of them might even be in direct confl ict to the original moral position. If this occurs, it is possible to characterize it as a paradox of moralistic fallacy. Th e possibility of this paradox provides a further reason not to prevent any scientifi c inquiries and not to depict any knowledge as dangerous. and V článku je rozveden koncept moralistického omylu, který předložil B. D. Davis. Jsou diskutovány základní charakteristiky tohoto omylu s cílem představit jeho obecnou formu. Moralistický omyl má přitom nechtěné následky, z nichž některé dokonce mohou být v přímém rozporu s původní morální pozicí, která stojí v začátku tohoto samotného omylu. Pokud takovýto stav nastane, lze ukázat, že moralistický omyl způsobuje paradox. Možnost takovéhoto paradoxu pak poskytuje důvod k tomu, aby bylo odmítnuto omezování vědeckého zkoumání a aby nebyla žádná znalost charakterizována jako nebezpečná.
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
68364. The parasitoid Praon volucre (Hymenoptera: Braconidae: Aphidiinae) as a potential biological control agent of the aphid Uroleucon ambrosiae (Hemiptera: Aphididae) on lettuce in Brazil
- Creator:
- de Conti, Bruno Freitas, Bueno, Vanda Helena Paes, and Sampaio, Marcus Vinicius
- Type:
- article, model:article, and TEXT
- Subject:
- Biological control, host quality, host size, development, aphid, Uroleucon ambrosiae, Macrosiphum euphorbiae, parasitoid, Praon volucre, and Lactuca sativa
- Language:
- English
- Description:
- The aphid Uroleucon ambrosiae (Thomas) is one of the principal pests found on greenhouse lettuce crops, and there is no efficient biological control agent of this pest in Brazil. This work evaluates the aphid U. ambrosiae as a host for the parasitoid Praon volucre (Haliday), aimed at using P. volucre as a potential biological control agent of U. ambrosiae on lettuce. As Macrosiphum euphorbiae (Thomas) is a common host of P. volucre in the field, the development of the parasitoid was compared on these two aphid species. Twenty nymphs of the 2nd instar were kept with P. volucre for one hour at 22 ± 1°C, 70 ± 10% RH and a 12 h photophase. The size of the aphid's tibiae at the moment of oviposition indicated that there was no significant size difference between U. ambrosiae (0.6 ± 0.02 mm) and M. euphorbiae (0.7 ± 0.03 mm). When mummies were formed, M. euphorbiae had significantly longer tibia (1.5 ± 0.03 mm) than U. ambrosiae (1.4 ± 0.02 mm). No significant differences were detected in the percentage emergence (74.9 ± 7.92 and 87.5% ± 3.31 for U. ambrosiae and M. euphorbiae, respectively), or proportion of female offspring (56.2 ± 7.62 and 44.2 ± 7.14%). The development time from oviposition to adult and longevity of females and males of P. volucre reared on the two host species were not different. High parasitism levels were recorded for both host aphid species, but the percentage parasitism of M. euphorbiae (54.4 ± 4.40) was higher than of U. ambrosiae (35.6 ± 5.30). Female parasitoids reared on M. euphorbiae had longer tibiae (0.78 ± 0.01 mm) than those reared on U. ambrosiae (0.72 ± 0.01 mm). Our results demonstrate that the alternative host species U. ambrosiae, compared to the natural host species M. euphorbiae, affects the female's size, but did not affect parasitoid development time, longevity, emergence or sex ratio. The parasitoid P. volucre seems to be a good candidate for using as a biological control agent of U. ambrosiae on lettuce in Brazil.
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
68365. The parasitoid species complex associated with sexual and parthenogenetic Naryciinae (Lepidoptera: Psychidae): Integrating ecological and molecular analyses
- Creator:
- Elzinga, Jelmer A., Zwakhals, Kees, Mappes, Johanna, and Grapputo, Alessandro
- Type:
- article, články, model:article, and TEXT
- Subject:
- Zoologie, entomologie, barcoding, larval remains, parasitism, parthenogenesis, sex ratio, COI, COII, Wingless, Hymenoptera, Braconidae, Ichneumonidae, Lepidoptera, Psychidae, Naryciinae, 2, and 59
- Language:
- English
- Description:
- a1_This study describes the parasitoid species complex associated with seven closely related species of sexual (Siederia rupicollella, S. listerella, Dahlica lazuri, D. charlottae and D. lichenella) and parthenogenetic (Dahlica fennicella and D. triquetrella) Naryciinae (Lepidoptera: Psychidae) in Central Finland. A thorough ecological analysis of all the species of parasitoids recorded was combined with analyses of molecular data. Mitochondrial and nuclear DNA data were obtained from all the species in order to (1) detect cryptic species associated with host specialization, (2) assign undescribed males to females, and (3) verify the morphological identification of closely related species. A DNA barcoding technique was employed to identify host species from parasitized larval remains. By sampling more than 10,000 host larvae, of which 25.7% were parasitized, nine parasitoid species were identified morphologically, including both koinobionts (Ichneumonidae: Diadegma incompletum, Macrus parvulus, Trachyarus borealis, T. solyanikovi, T. fuscipes, T. brevipennis and Braconidae: Meteorus affinis) and idiobionts (Ichneumonidae: Orthizema flavicorne, Gelis fuscicornis). Ecological characteristics such as time and mode of host attack, time of emergence and level of specialization differed widely. The results show that differences in parasitoid biology need to be taken into account when studying differences in percentage parasitism of sexual and parthenogenetic Naryciinae. The molecular data revealed that one parasitoid species M. parvulus may consist of two cryptic forms associated with the sexual and parthenogenetic hosts, respectively. The data further establishes that T. brevipennis and some T. fuscipes are in fact morphotypes of one species. The large variation in mitochondrial DNA within species and its inconsistency with nuclear DNA demonstrate that current species and genus delimitation is inadequate in the, a2_Trachyarus species group. Our study shows that it is essential to use DNA barcoding methods when investigating host-parasitoid complexes., and Jelmer A. Elzinga, Kees Zwakhals, Johanna Mappes, Alessandro Grapputo.
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
68366. The past as and existential problem in the fiction of J. Durych, K. Schulz and M. V. Kratochvíl
- Creator:
- Voisine-Jechova, Hana and Voisine, Jacques
- Format:
- bez média and svazek
- Type:
- model:article and TEXT
- Subject:
- Slavic studies and Czech literature
- Language:
- German
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
68367. The pattern of changes in photosynthetic apparatus in response to cold acclimation and de-acclimation in two contrasting cultivars of oilseed rape
- Creator:
- Rapacz, M. and Hura, K.
- Format:
- bez média and svazek
- Type:
- model:article and TEXT
- Subject:
- Brassica napus var. oleifera, carbon metabolism, chlorophyll fluorescence, cultivar differences, elongation growth rate, low temperature, photosynthesis, ribulose-1,5-bisphosphate carboxylase/oxygenase, and sucrose-phosphate sythase
- Language:
- Multiple languages
- Description:
- In spring and winter cultivars of oilseed rape (Brassica napus var. oleifera), acclimation of photosynthetic apparatus to cold was connected with the increase in activities of ribulose-1,5-bisphosphate carboxylase/oxygenase (RuBPCO) and sucrose-phosphate synthase (SPS). Conversely, cold de-acclimation entailed the decline of RuBPCO and SPS activities. The rate of this photosynthetic de-acclimation might depend on day temperature. On the other hand, temperature rise during de-acclimation (identical during the day and night) resulted in the improvement of photosynthetic activity measured by means of chlorophyll fluorescence. An increase in SPS activity (and even transitory increase in RuBPCO activity) was observed when the elongation growth rate (EGR) accelerated during de-acclimation. Throughout re-acclimation, plants with high EGR were unable to maintain or recover higher photosynthetic capacity, despite the fact that SPS activity remained high or even increased during re-acclimation. and M. Rapacz, K. Hura.
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
68368. The PDE describing constant mean curvature surfaces
- Creator:
- Wu, Hongyou
- Format:
- bez média and svazek
- Type:
- model:article and TEXT
- Subject:
- constant mean curvature surfaces, nonlinear partial differential equation, dressing action, and Weierstrass type representation
- Language:
- English
- Description:
- We give an expository account of a Weierstrass type representation of the non-zero constant mean curvature surfaces in space and discuss the meaning of the representation from the point of view of partial differential equations.
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
68369. The perceived stress scale: reliability and validity study in the Czech Republic
- Creator:
- Figalová, Nikol and Charvát, Miroslav
- Format:
- počítač and online zdroj
- Type:
- model:article and TEXT
- Subject:
- Perceived Stress Scale, translation, reliability, validity, scale, Škála vnímaného stresu, překlad, reliabilita, validita, and škála
- Language:
- Czech
- Description:
- Objectives. The aim of this study was to create a Czech translation of the Perceived Stress Scale (PSS), to assess its psychometric properties on a representative sample of the Czech general adult population, and to compare the original 14-item version (PSS-14) with the shortened 10-item (PSS-10) and four-item (PSS-4) versions. Sample and setting. Two pilot studies were conducted to create the final Czech translation of the scale (n = 365 and n = 420). The final version of the Czech PSS was administered to a sample of the Czech general adult population (n = 1725 of whom 981 were women, M = 44.32,SD = 12.8). The Beck Depression Inventory (BDI-II) or the State-Trait Anxiety Inventory (STAI) were administered alongside the PSS to a part of the sample. A retest measurement after 14 days was conducted (n = 159). Statistical analysis. Using the confirmatory factor analysis, the one-factor, two-factor and bifactor models were compared. The internal consistency, stability in time, and convergent validity of the scale, as well as the known-group differences were assessed. The three versions of the PSS were compared. Results. The confirmatory factor analysis sup-ported the bifactor model of the PSS-14 and PSS-10, and the two-factor model of the PSS-4. All versions of the scale showed good internal consistency and stability in time. There was a moderate to strong positive correlation between the PSS and the BDI-II and STAI. Differences based on age, sex, education level, and situ-ational factors were found. Overall, the PSS-10 showed the best psychometric properties of all three versions of the scale. Study limitation. The sample consisted mostly of highly educated respondents. and Cíle. Cílem předkládané studie bylo vytvořit český překlad Škály vnímaného stresu (PSS), ověřit jeho psychometrické vlastnosti na repre-zentativním vzorku běžné české dospělé po-pulace, a porovnat psychometrické vlastnosti původní čtrnáctipoložkové škály (PSS-14) se zkrácenou desetipoložkovou (PSS-10) a čtyřpo-ložkovou (PSS-4) verzí. Výzkumný soubor a metody získávání dat. Při tvorbě českého překladu škály byly provedeny dvě pilotní studie (n = 365 a n = 420). Finální překlad škály byl administrován vzorku běž-né české populace (n = 1725, z toho 981 žen, M = 44,32, SD = 12,8). Části vzorku byla také administrována Beckova škála deprese (BDI-II) nebo Dotazník na měření úzkosti a úzkostlivosti (STAI). Po 14 dnech proběhl retest, kterého se zúčastnilo 159 respondentů. Analýza dat. Pomocí konfirmační faktorové analýzy autoři porovnali jednofaktorový, dvou-faktorový a bifaktorový model škály. Ověřili vnitřní konzistenci škály, její stabilitu v čase, konvergentní validitu a rozdíly mezi známými skupinami. Porovnali vlastnosti jednotlivých forem PSS. Výsledky. Konfirmační faktorová analýza pod-pořila bifaktorový model PSS-14 i PSS-10 a dvoufaktorový model PSS-4. Všechny tři formy škály dosahovaly dobré hodnoty vnitřní konzis-tence i stability v čase. Korelace PSS s BDI-II a STAI ukázaly středně silný až silný pozitiv-ní vztah. Byly nalezeny rozdíly v závislosti na věku, pohlaví, vzdělání a řadě situačních fakto-rů. Nejlepších psychometrických vlastností do-sahovala desetipoložková verze škály. Limity studie. Ve zkoumaném vzorku dominují respondenti s vysokoškolským vzděláním.
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
68370. The performance of backpropagation networks which use gradient descent on sigmoidal steepness
- Creator:
- Leung, Wing Kai
- Format:
- bez média and svazek
- Type:
- model:article and TEXT
- Subject:
- neural networks, backpropagation, sigmoidal steepness, neural metrics, and algorithmic complexity
- Language:
- English
- Description:
- Backpropagation which uses gradient descent on the steepness of the sigmoid function (BPSA) has been widely studied (e.g. Kruschke et al. [1]). However, most of these studies only analysed the BPSA empirically where no adequate measurements of the network’s quality characteristics (e.g. efficiency and complexity) were given. This paper attempts to show that the BPSA is more efficient than the standard BPA by quantitatively comparing the convergence performance of both algorithms on several benchmark application problems. The convergence performance is measured by the values of the neural metrics [2] evaluated in the training process.
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public