1,721,088 research outputs found
Grid cells are modulated by local head direction
No full textIn vivo tetrode recordings from the medial entorhinal cortex of mice during open field exploration. This data set contains recordings from grid cells, conjunctive cells and other spatial cells. Please look at Gerlei_et_at_2020_where_to_find_data_and_code.xlsx to find which files to download to replicate specific figures. If you only need the data from the sorted clusters, (firing times, position...) download SORTED_CLUSTERS.zipNolan, Matthew; Gerlei, Klara; Passlack, Jessica; Hawes, Ian; Vandrey, Brianna; Stevens, Holly; Papastathopoulos, Ioannis. (2020). Grid cells are modulated by local head direction, [dataset]. University of Edinburgh. https://doi.org/10.7488/ds/2855
Going Beyond Counting First Authors in Author Co-citation Analysis
Get PDFThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
Variations on the Author
Get PDF“Variations on the Author” discusses two of Eduardo Coutinho’s recent films (Um Dia na Vida, from 2010, and Últimas Conversas, posthumously released in 2015) and their contribution to the general question of documentary authorship. The director’s filmography is characterized by a consistent yet self-effacing form of authorial self-inscription: Coutinho often features as an interviewer that rather than express opinions propels discourses; an interviewer that is good at listening. This mode of self-inscription characterizes him as an author who is not expressive but who is nonetheless markedly present on the screen. In Um Dia na Vida, however, Coutinho is completely absent form the image, while Últimas Conversas, on the contrary, includes a confessional prologue that moves the director from the margins to the center of his films. This article examines the ways in which these works stand out in the filmography of a director who offers new insights into the notion of cinematic authorship
Appropriate Similarity Measures for Author Cocitation Analysis
Get PDFWe provide a number of new insights into the methodological discussion about author cocitation analysis. We first argue that the use of the Pearson correlation for measuring the similarity between authors’ cocitation profiles is not very satisfactory. We then discuss what kind of similarity measures may be used as an alternative to the Pearson correlation. We consider three similarity measures in particular. One is the well-known cosine. The other two similarity measures have not been used before in the bibliometric literature. Finally, we show by means of an example that our findings have a high practical relevance.information science;Pearson correlation;cosine;similarity measure;author cocitation analysis
Dispelling the Myths Behind First-author Citation Counts
Get PDFWe conducted a full-scale evaluative citation analysis study of scholars in the XML research field to explore just how different from each other author rankings resulting from different citation counting methods actually are, and to demonstrate the capability of emerging data and tools on the Web in supporting more realistic citation counting methods. Our results contest some common arguments for the continued
use of first-author citation counts in the evaluation of scholars, such as high correlations between author rankings by first-author citation counts and other citation
counting methods, and high costs of using more realistic citation counting methods that are not well-supported by the ISI databases. It is argued that increasingly available digital full text research papers make it possible for citation analysis studies to go beyond what the ISI databases have directly supported and to employ more
sophisticated methods
Relationships between cyanobacteria and water colour in Central North Island lakes of contrasting trophic status
Get PDFNutrient enrichment of lakes and rising global temperatures promote the proliferation of cyanobacteria. Cyanobacterial blooms are becoming more widespread and increasing in frequency, size and duration, causing a cascade of detrimental changes to freshwater ecosystems. Improved lake monitoring techniques are required for early detection of bloom initiation to allow mitigation measures to be better targeted. Recent studies suggest remote sensing of the reflectance spectra of lakes can be a valuable tool to map the distribution of potentially toxic cyanobacteria in near-real time, though as yet, these are not widely used in New Zealand. In this study, three Rotorua and five Waikato Lakes were sampled to determine hyperspectral reflectance, phytoplankton composition and biovolume, chlorophyll a, phycocyanin concentrations, and optically active constituents. The data obtained were used to develop algorithms to examine the utility of reflectance data to aid in estimations of chlorophyll a and phycocyanin concentrations and phytoplankton composition with a particular focus on cyanobacteria. Results show that relationships amongst reflectance-related attributes, including chromophoric dissolved organic material, suspended solids and absorption properties of phytoplankton and pigment concentrations varied among the lakes and, to varying extents, over time. Properties of specific regions of reflectance spectra could be used to predict concentrations of these two pigments, but reflectance was not effective in separating the effects of phytoplankton composition from the other optically active variables. The two algorithms best suited these lakes for estimation of chlorophyll a and phycocyanin showed strong relations with the observed pigments at R2 = 0.83 and R2 = 0.92, respectively. This suggests reflectance spectra and the appropriate algorithm can be used to yield estimations of chlorophyll a and phycocyanin concentrations within inland waters with a wide variation of bio-optical characteristics. Such information could contribute to the development of an early warning system to predict cyanobacterial biovolume in New Zealand lakes using remote sensing
koamabayili/VECTRON-author-checklist: VECTRON author checklist
No full textWe have done our best to complete the author checklist relating to the use of animals in the hut study. Note that the objective for the hut study was to evaluate the IRS treatment applications for residual efficacy against Anopheles mosquitoes, including the local An. coluzzii mosquito population. Cows were only used to attract mosquitoes into the huts and no tests were carried out directly on the cows. The author checklist is intended for use with studies where experiments are carried out on animals, which is why we have had such difficulty in completing this for the hut study, as many of the questions do not relate to how the cows were used
Resilience of microbial mats in Antarctic ponds to climate-relevant environmental disturbance
Get PDFContinental Antarctica is a cold desert, where the hydrologic system is dependent on melting of snow and ice. In a warming climate it is projected that there will be a significant change in precipitation, evaporation, cloud formation, all affecting the ice-water dynamic. Hydrology is considered vulnerable to climatic change. Hydrological change cascades through the environment affecting Antarctic ponds which are important centres for inland microbial biodiversity. An understanding of community vulnerability to anticipated change can be developed through assessing organism and functional resilience to climate-related and other forms of disturbance. The aim of this study is to identify the effects of disturbance on microbial communities, specifically cyanobacterial mats, with a particular focus on changes that may occur resultant to anthropogenic climate change.
This study undertook three experiments, which identified impacts of disturbance on three key cyanobacterial mat functions – nitrogen fixation, photosynthesis/respiration, and recovery after a physical disturbance. Sampling was undertaken in the McMurdo Ice Shelf (MIS) meltwater ponds in late January 2019. The design for the nitrogen fixation experiment used a natural gradient of conductivity across five ponds (Fresh, Casten, P70, Brack and Salt) in a space-for-time approach that compared microbial composition and nitrogen fixation rates. The light disturbance study completed in New and P70 ponds tested mat ability to retain photosynthesis and respiration under a pulsed disturbance – covering microbial mats with shade cloth for 12 months. In this study the light-photosynthesis response and mat composition were analysed when shaded and not shaded (control plots). The third experiment examined short-term response to physical disturbance by observing the recovery of mat structure and community composition for 2 years was also completed in New and P70 ponds.
It was identified that there was no significant change in acetylene reduction (as a proxy for nitrogen fixation) over the salinity range. Acetylene reduction ranged between 22.4 ± 3.4 µMol/m²/h in Brack Pond (conductivity = 10.5 mS/cm) and 49.6 ± 17.1 µMol/m²/h in Casten Pond (conductivity = 2.3 mS/cm). The acetylene reduction difference was statistically significant between Brack Pond and Casten Pond (F = 0.006 (Bonferroni Correction significance of F ≤ 0.01)). Microbial mat composition changed across the conductivity gradient, but significant proportions of different N-fixing and mat-forming genera were evident along the salt gradient, suggesting functional resilience through species turnover.
It was also identified that when receiving a 95-96% decrease in ambient light photosynthetic bacteria were able to maintain photosynthesis and respiration at similar rates within the microbial mats. However, in shaded plots the maximum net oxygen production occurred at an average irradiance between 350 – 450 µMol photons m-²s-¹ and was inhibited at higher levels. In control plots the maximum net oxygen production was ≥900 µMol photons m-²s-¹. In control samples net photosynthesis exceeds zero (photosynthesis exceeds respiration) at ~275 µMol photons m-²s-¹, in shaded samples this occurred at ~100 µMol photons m-²s-¹. Rapid shifts in the appearance of mats under, and after shading led to the conclusion that the acclimation may be based on vertical migration of cyanobacteria within the mats, which showed no significant changes in relative abundance of taxa.
After physical removal of microbial mat, communities were shown to reform to similar relative abundances as control samples within two years of the disturbance, within this experiment a successional change in species abundance was observed.
This research highlights the resilience of microbial mat populations on the MIS to the types of change that are anticipated to accompany climate change. It supports conclusions previously identified that cyanobacterial mats are functionally resilient to short-term and long-term disturbances. Ongoing research will improve the knowledge on the resilience of other functions required in these environments
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