Progressive paradoxical sleep deprivation impairs partial memory following learning tasks in rats

BACKGROUND： Complex learning tasks result in a greater number of paradoxical sleep phases, which can improve memory. The effect of paradoxical sleep deprivation, induced by ＂flower pot＂ technique, on spatial reference memory and working memory require further research. OBJECTIVE： To observe the effect of progressive paradoxical sleep deprivation in rats, subsequent to learning, on memory using the Morris Water Maze. DESIGN, TIME AND SETTING： Controlled observation experiment. The experiment was performed at the Laboratory of Neurobiology, Department of Anatomy, Histology and Embryology, School of Basic Medical Sciences, Lanzhou University from December 2006 to October 2007. MATERIALS： Twenty-eight, male, Wistar rats, 3-4 months old, were provided by the Experimental Animal Center of Lanzhou University. The Morris Water Maze and behavioral analyses system was purchased from Genheart Company, Beijing, China. METHODS： All animals, according to a random digits table, were randomly divided into paradoxical sleep deprivation, tank control, and home cage control groups. Paradoxical sleep deprivation was induced by the ＂flower pot＂ technique for 72 hours, housing the rats on small platforms over water. Rats in the ＂tank control＂ and ＂home cage control＂ groups were housed either in a tank with large platforms over the water or in normal cages without paradoxical sleep deprivation. MAIN OUTCOME MEASURES： Morris Water Maze was employed for task learning and spatial memory testing. Rats in all groups were placed at six random starting points each day for four consecutive days. Each placement was repeated for two trials; the first trial represented reference memory and the second working memory. Rats in the first trial were allowed to locate the submerged platform within 120 seconds. Data, including swimming distance, escape latency, swimming velocity, percentage of time in correct quarter, and memory scores were recorded and analyzed automatically by behavioral analyses systems for Morris Water Maze. RESULTS： Twenty-eight rats were included in the final analysis, without any loss. In the first trial, between day 2 and 4, escape latency and swimming distance increased significantly in the paradoxical sleep deprivation group compared to the home cage control and tank control groups （P 〈 0.01）; percentage of time in correct quarter and memory scores, however, decreased in the paradoxical sleep deprivation group compared to the home cage control and tank control groups （P 〈 0.01）. The escape latency, swimming distance, percentage of time in correct quarter, and memory scores in the second trial was not significantly different among the three groups （P 〉 0.05）. CONCLUSION： Paradoxical sleep deprivation inhibits spatial reference memory, but not working memory.

An address regional tessellation method for spatial subdivision and geocoding in digital earth system

With the increased use of locational information,spatial location referencing and coding methods have become much more important to the mining of both geographical and nongeographical data in digital earth system.Unfortunately,current methods of geocoding,based on reverse lookup of coordinates for a given address,have proven too lossy with respect to administrative and socioeconomic data.This paper proposes a spatial subdivision and geocoding model based on spatial address regional tessellation(SART).Given a hierarchical address object definition,and based on the‘region of influence’characteristics of an address,SART creates multiresolution spatial subdivisions by irregular and continuous address regions.This model reflects most of the geographical features and many of the social and economic implications for a given address.It also better reflects the way people understand addresses and spatial locations.We also propose an appropriate method of geocoding for standard addresses(SART-GC).The codes generated by this method can record address footprints,hierarchical relationships,and spatial scales in a single data structure.Finally,by applying our methods to the Shibei District of Qingdao,we demonstrate the suitability of SART-GC for multi-scale spatial information representation in digital earth systems.

The effects of inactivated SARS-CoV-2 vaccination and subsequent infection of pregnant mice on the behaviors of offspring

The mass inoculation of severe acute respiratory syndrome coronavirus 2(SARS-CoV-2)vaccines to induce herd immunity is one of the most effective measures we can deploy in the fight against coronavirus disease 2019(COVID-19).Pregnant women are prone to a higher risk of COVID-19,and maternal infection is a risk fac-tor for a range of neurological disorders leading to abnormal behavior in adulthood.However,there are limited clinical data to support whether vaccination or infection post-immunization in pregnant women can affect the behavioral cognition of fetuses in adulthood.In this study,human angiotensin-converting enzyme 2 pregnant mice(F0 generation)were immunized with CoronaVac and then infected with SARS-CoV-2.Subsequently,we analyzed the behavioral cognition of their adult offspring(F1 gen-eration)using the open-field test and Morris water maze test.The adult F1 generation did not exhibit any impairments in spontaneous locomotor activity or spatial refer-ence memory.

Addressing administrative units in international tsunami early warning systems: shortcomings in international geocode standards

Administrative units reflect the territorial hierarchies established within all countries of the world.The units are addressable with geocodes that provide a bijective mapping between territories and unique identification codes.Early warning systems for natural or man-made hazards often map affected or threatened areas to administrative units to establish a spatial reference that is comprehensible to all parts of the population.Addressing these territories in an international context has several requirements,such as worldwide coverage,completeness and topicality,which must be met by geocode standards.In this paper,the practicability and suitability of international geocode standards are examined in the context of the requirements of large-scale early warning systems.This paper exposes the insufficiencies and limitations of existing geocode standards International Organization for Standardization(ISO)-3166,Second Administrative Level Boundaries data set project(SALB)and Nomenclature of the Territorial Units for Statistics(NUTS)and emphasises the suitability of the non-official hierarchical administrative subdivision codes(HASC).The analysis is framed in the context of addressing affected areas for an Indian Ocean tsunami early warning system.This system was developed within the Distant Early Warning Systems project according to the requirements of the United Nations Educational,Scientific and Cultural Organization(UNESCO)Intergovernmental Oceanic Commission for Regional Tsunami Watch Providers(RTWPs).

The Grammaticalization and Lexicalization of Space Deixis:A cross-linguistic analysis

Space deixis is concerned with the specification of location in space relative to that of the participants at coding time in a speech event. Cross-linguistically, it is commonly expressed by the use of (i) demonstratives including both demonstrative pronouns and demonstrative adjectives, (ii) deictic adverbs of space, (iii) deictically marked third-person pronouns, and (iv) deictic directionals including both motion affixes, morphemes and particles, and motion verbs. In this article, I shall provide a descriptive analysis of the grammaticalization and lexicalization of space deixis. Data is drawn from a wide variety of genetically unrelated and structurally distinct languages to show the diversity and richness of spatial deictic systems in the world’s languages.