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31782. Rat Spatial Memory Tasks Adapted for Humans: Characterization in Subjects with Intact Brain and Subjects with Medial Temporal Lobe Lesions
- Creator:
- Bohbot, V.D., Robert Jech, Evžen Růžička, Lynn Nadel, Kalina, M., Kateřina Seltenreichová, and Bureš, J.
- Format:
- print, bez média, and svazek
- Type:
- article, studie, model:article, and TEXT
- Subject:
- Fyziologie člověka a srovnávací fyziologie, fyziologie člověka, human physiology, 14, and 612
- Language:
- English
- Description:
- a1_In the present paper we describe five tests, 3 of which were designed to be similar to tasks used with rodents. Results obtained from control subjects, patients with selective thermo-coagulation lesions to the medial temporal lobe and results from non-human primates and rodents are discussed. The tests involve memory for spatial locations acquired by moving around in a room, memory for objects subjects interacted with, or memory for objects and their locations. Two of the spatial memory tasks were designed specifically as analogs of the Morris water task and the 8-arm radial-maze tasks used with rats. The Morris water task was modeled by hiding a sensor under the carpet of a room (Invisible Sensor Task). Subjects had to learn its location by using an array of visual cues available in the room. A path integration task was developed in order to study the non-visual acquisition of a cognitive representation of the spatial location of objects. In the non-visual spatial memory task, we blindfolded subjects and led them to a room where they had to find 3 objects and remember their locations. We designed an object location task by placing 4 objects in a room that subjects observed for later recall of their locations. A recognition task, and a novelty detection task were given subsequent to the recall task. An 8-arm radial-maze was recreated by placing stands at equal distance from each other around the room, and asking subjects to visit each stand once, from a central point. A non-spatial working memory task was designed to be the non-spatial equivalent of the radial maze. Search paths recorded on the first trial of the Invisible Sensor Task, when subjects search for the target by trial and error are reported., a2_An analysis of the search paths revealed that patients with lesions to the right or left hippocampus or parahippocampal cortex employed the same type of search strategies as normal controls did, showing similarities and differences to the search behavior recorded in rats. Interestingly, patients with lesions that included the right parahippocampal cortex were impaired relative to patients with lesions to the right hippocampus that spared the parahippocampal cortex, when recall of the sensor was tested after a 30 min delay (Bohbot et al. 1998). No differences were obtained between control subjects and patients with selective thermal lesions to the medial temporal lobe, when tested on the radial-maze, the non-spatial analogue to the radial-maze and the path integration tasks. Differences in methodological procedures, learning strategies and lesion location could account for some of the discrepant results between humans and non-human species. Patients with lesions to the right hippocampus, irrespective of whether the right parahippocampal cortex was spared or damaged, had difficulties remembering the particular configuration and identity of objects in the novelty detection of the object location task. This supports the role of the human right hippocampus for spatial memory, in this case, involving memory for the location of elements in the room; learning known to require the hippocampus in the rat., V.D. Bohbot, R. Jech, E. Růžička, L. Nadel, M. Kalina, K. Štěpánková , J. Bureš., and Obsahuje bibliografii
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
31783. Rat Submandibular Gland during the Maturation Process: Changes in Enzyme Activities, Protein and Lectin-Binding Profiles
- Creator:
- Przybyło, M., Litýnska, A., Hoja-Łyukowicz, D., and Kremser, E.
- Type:
- article, model:article, and TEXT
- Subject:
- Lectins, Lysosomes, Maturation, Oligosaccharides, and Submandibular gland
- Language:
- English
- Description:
- The total protein glycosylation profile and specific activity of lysosomal enzymes were investigated in rat submandibular glands isolated from very young (1-month), young (1.5-months) and adult rats (3-months) rats. The specific activity of lysosomal hydrolases (i.e. acid phosphatase, arylsulfatases A and B, β-N-acetyl-D-glucosaminidase, β-galactosidase and β-glucuronidase) decreased in parallel to increasing age of the animals. Furthermore, the thermal stability of acid phosphatase and β-N-acetyl-D-glucosaminidase was influenced by the age of rats. Age-related changes in protein profile regarding the intensity of particular bands as well as the appearance of certain proteins limited to special age groups were also demonstrated as revealed by Coomassie and lectin staining. Moreover, the marked age-related increase in structures Man (α1-2, α1-3, α1-6) Man, Fuc (α1-6) GlcNAc as well as Gal (β1-3) GlcNAc was observed, whereas staining with terminal NeuAc and GlcNAc showed an inverse correlation. The reaction with (β1-6) branched N-glycans and Gal (β1-3) Gal structures was limited to 1-month-old rats. No significant changes in a specific reaction with NeuAc (α2-3) Gal were observed. We speculate that the observed differences with respect to protein and glycosylation profiles between 1-month-old rats and older ones could be caused by a modification of the diet composition as well as by the functional and morphological maturation of the rat submandibular gland.
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
31784. Rate of convergence for a class of RCA estimators
- Creator:
- Vaněček, Pavel
- Format:
- bez média and svazek
- Type:
- model:article and TEXT
- Subject:
- RCA, parameter estimation, and rate of convergence
- Language:
- English
- Description:
- This work deals with Random Coefficient Autoregressive models where the error process is a martingale difference sequence. A class of estimators of unknown parameter is employed. This class was originally proposed by Schick and it covers both least squares estimator and maximum likelihood estimator for instance. Asymptotic behavior of such estimators is explored, especially the rate of convergence to normal distribution is established.
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
31785. Rates of molecular evolution and genetic diversity in European vs. North American populations of invasive insect species
- Creator:
- Young, Robert G., Mitterboeck, T. Fatima, Loeza-Quintana, Tzitziki , and Adamowicz, Sarah J.
- Format:
- počítač and online zdroj
- Type:
- model:article and TEXT
- Subject:
- Non-native, invasive, molecular evolutionary rates, comparative method, cytochrome c oxidase subunit I, COI, DNA barcoding, population genetics, North America, Europe, and insects
- Language:
- English
- Description:
- Many factors contribute to the 'invasive potential' of species or populations. It has been suggested that the rate of genetic evolution of a species and the amount of genetic diversity upon which selection can act may play a role in invasiveness. In this study, we examine whether invasive species have a higher relative pace of molecular evolution as compared with closely related non-invasive species, as well as examine the genetic diversity between invasive and closely related species. To do this, we used mitochondrial cytochrome c oxidase subunit I sequences of 35 species with a European native range that are invasive in North America. Unique to molecular rate studies, we permuted across sequences when comparing each invasive species with its sister clade species, incorporating a range of recorded genetic variation within species using 405,765 total combinations of invasive, sister, and outgroup sequences. We observed no significant trend in relative molecular rates between invasive and non-invasive sister clade species, nor in intraspecific genetic diversity, suggesting that differences in invasive status between closely related lineages are not strongly determined by the relative overall pace of genetic evolution or molecular genetic diversity. We support previous observations of more often higher genetic diversity in native than invaded ranges using available data for this genetic region.
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
31786. Rathäuser als multifunktionale Räume der Repräsentation, der Parteiungen und des Geheimnisses /
- Type:
- text and monografie kolektivní
- Subject:
- Stupně místní, oblastní a ústřední správy, radnice, města, politika, zahraniční periodika a sborníky, přehledná zpracování světových dějin (chronologicky), města, obce, and dějiny správy
- Language:
- German and English
- Rights:
- unknown
31787. Rathäuser als multifunktionale Räume der Repräsentation, der Parteiungen und des Geheimnisses /
- Type:
- text and monografie kolektivní
- Subject:
- Stupně místní, oblastní a ústřední správy, radnice, města, politika, zahraniční periodika a sborníky, přehledná zpracování světových dějin (chronologicky), města, obce, and dějiny správy
- Language:
- German and English
- Rights:
- unknown
31788. Rational inattention to discrete choices: a new foundation for the multinomial logit model
- Creator:
- Matějka, Filip, McKay, Alisdair, Kejak, Michal, Univerzita Karlova. Centrum pro ekonomický výzkum a doktorské studium, and Národohospodářský ústav (Akademie věd ČR)
- Publisher:
- CERGE-EI
- Format:
- electronic and 24 s. : il.
- Type:
- model:monograph and TEXT
- Subject:
- Ekonomie, rozhodování, modelování a simulace, 005.311.6, 519.86/.87, (048.8), 4, and 33
- Language:
- English and Czech
- Description:
- Filip Matějka, Alisdair McKay., Obsahuje bibliografii a bibliografické odkazy., České resumé, and born digital
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
31789. Rational Łukasiewicz logic and DMV-algebras
- Creator:
- Gerla, Brunella
- Format:
- bez média and svazek
- Type:
- model:article and TEXT
- Subject:
- many-valued logic, fuzzy logic, Rational Łukasiewicz logic, DMV-algebras, completeness, and computational complexity
- Language:
- English
- Description:
- In this paper we present some results concerning the variety of divisible MV-algebras. Any free divisible MV-algebra is an algebra of continuous piecewise linear functions with rational coefficients. Correspondingly, the Rational Łukasiewicz logic is defined and its tautology problem is shown to be co-NP-complete.
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
31790. Rational realization of the minimum ranks of nonnegative sign pattern matrices
- Creator:
- Fang, Wei, Gao, Wei, Gao, Yubin, Gong, Fei, Jing, Guangming, Li, Zhongshan, Shao, Yanling, and Zhang, Lihua
- Format:
- print, bez média, and svazek
- Type:
- model:article and TEXT
- Subject:
- matematika, mathematics, sign pattern (matrix), nonnegative sign pattern, minimum rank, convex polytope, rational minimum rank, rational realization, integer matrix, condensed sign pattern, point-hyperplane configuration, 13, and 51
- Language:
- English
- Description:
- A sign pattern matrix (or nonnegative sign pattern matrix) is a matrix whose entries are from the set {+,−, 0} ({+, 0}, respectively). The minimum rank (or rational minimum rank) of a sign pattern matrix A is the minimum of the ranks of the matrices (rational matrices, respectively) whose entries have signs equal to the corresponding entries of A. Using a correspondence between sign patterns with minimum rank r ≥ 2 and point-hyperplane configurations in Rr−1 and Steinitz’s theorem on the rational realizability of 3-polytopes, it is shown that for every nonnegative sign pattern of minimum rank at most 4, the minimum rank and the rational minimum rank are equal. But there are nonnegative sign patterns with minimum rank 5 whose rational minimum rank is greater than 5. It is established that every d-polytope determines a nonnegative sign pattern with minimum rank d + 1 that has a (d + 1) × (d + 1) triangular submatrix with all diagonal entries positive. It is also shown that there are at most min{3m, 3n} zero entries in any condensed nonnegative m × n sign pattern of minimum rank 3. Some bounds on the entries of some integer matrices achieving the minimum ranks of nonnegative sign patterns with minimum rank 3 or 4 are established., Wei Fang, Wei Gao, Yubin Gao, Fei Gong, Guangming Jing, Zhongshan Li, Yanling Shao, Lihua Zhang., and Obsahuje seznam literatury
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public