420 research outputs found
Electromagnetic response of high-Tc superconductors -- the slave-boson and doped-carrier theories
We evaluate the doping dependence of the quasiparticle current and low
temperature superfluid density in two slave-particle theories of the tt't''J
model -- the slave-boson theory and doped-carrier theory. In the slave-boson
theory, the nodal quasiparticle current renormalization factor
vanishes proportionally to the zero temperature superfluid density ;
however, we find that away from the limit displays a
much weaker doping dependence than . A similar conclusion applies to
the doped-carrier theory, which differentiates the nodal and antinodal regions
of momentum space. Due to its momentum space anisotropy, the doped-carrier
theory enhances the value of in the hole doped regime, bringing it to
quantitative agreement with experiments, and reproduces the asymmetry between
hole and electron doped cuprate superconductors. Finally, we use the
doped-carrier theory to predict a specific experimental signature of local
staggered spin correlations in doped Mott insulator superconductors which, we
propose, should be observed in STM measurements of underdoped high-Tc
compounds. This experimental signature distinguishes the doped-carrier theory
from other candidate mean-field theories of high-Tc superconductors, like the
slave-boson theory and the conventional BCS theory.Comment: 12 pages, RevTeX4, homepage http://dao.mit.edu/~we
Spike Avalanches Exhibit Universal Dynamics across the Sleep-Wake Cycle
Scale-invariant neuronal avalanches have been observed in cell cultures and
slices as well as anesthetized and awake brains, suggesting that the brain
operates near criticality, i.e. within a narrow margin between avalanche
propagation and extinction. In theory, criticality provides many desirable
features for the behaving brain, optimizing computational capabilities,
information transmission, sensitivity to sensory stimuli and size of memory
repertoires. However, a thorough characterization of neuronal avalanches in
freely-behaving (FB) animals is still missing, thus raising doubts about their
relevance for brain function. To address this issue, we employed chronically
implanted multielectrode arrays (MEA) to record avalanches of spikes from the
cerebral cortex (V1 and S1) and hippocampus (HP) of 14 rats, as they
spontaneously traversed the wake-sleep cycle, explored novel objects or were
subjected to anesthesia (AN). We then modeled spike avalanches to evaluate the
impact of sparse MEA sampling on their statistics. We found that the size
distribution of spike avalanches are well fit by lognormal distributions in FB
animals, and by truncated power laws in the AN group. The FB data are also
characterized by multiple key features compatible with criticality in the
temporal domain, such as 1/f spectra and long-term correlations as measured by
detrended fluctuation analysis. These signatures are very stable across waking,
slow-wave sleep and rapid-eye-movement sleep, but collapse during anesthesia.
Likewise, waiting time distributions obey a single scaling function during all
natural behavioral states, but not during anesthesia. Results are equivalent
for neuronal ensembles recorded from V1, S1 and HP. Altogether, the data
provide a comprehensive link between behavior and brain criticality, revealing
a unique scale-invariant regime of spike avalanches across all major behaviors.Comment: 14 pages, 9 figures, supporting material included (published in Plos
One
Support for automatic refactoring of business logic
Software’s structure profoundly affects its development and maintenance costs. Poor software’s structure may lead to well-known design flaws, such as large modules or long methods. A possible ap- proach to reduce a module’s complexity is the Extract Method refactor- ing technique. This technique allows the decomposition of a large and complex method into smaller and simpler ones, while reducing the orig- inal method’s size and improving its readability and comprehension. The OutSystems platform is a low-code platform that allows the de- velopment of web and mobile applications that rely on a set of visual Domain-Specific Languages (DSLs). Even low-code languages when im- properly used can lead to software that has maintenance issues like long methods.
Thus, the purpose of this paper is to present the research and devel- opment done to provide the OutSystems platform with a tool that au- tomatically suggests Extract Method refactoring opportunities. The re- search combines program slicing techniques with code complexity metrics to calculate the best refactoring opportunities that preserve programs’ functionality.
The proposed approach was tested on typical OutSystems apps and was shown to be able to reduce the overall applications’ complexity.info:eu-repo/semantics/publishedVersio
Users satisfaction regarding the service provided in community pharmacies
During the last century, the pharmacy professionals have significantly being professionalized, the user is a high priority and not just limited to the sale of pharmaceuticals. As such, it is necessary to know the users, their needs and expectations, their opinions and preferences. This transversal study, observational, correlational, aimed to: determine the degree of satisfaction with the attendance in community pharmacies, if there is a relationship between factors of a personal nature (age and gender) and satisfaction, trying to identify which aspects improve in order to increase satisfaction levels. The sample consisted of 525 respondents. Data collection was conducted in the period from October 2012 to January 2013 in four locations in northern Portugal. It was used a questionnaire consisting of three parts: the first contained items of personal characterization, the second consisted of the scale "Pharmacy Services Questionnaire" (FSQ) validated for the Portuguese language, developed by Larson et al. (2002) and the last had questions about the respondents' opinion. The results showed that the degree of satisfaction with the services of community pharmacies was in majority an average to 39 % and good for 46,1% . Having in mind the factor by gender, females showed a higher degree of satisfaction. Regarding the age group, older users had the highest degree of satisfaction. It was concluded that, generally, community pharmacies bring a higher degree of satisfaction in the older and the female users. "How the pharmacy professionals explain possible side effects" and "how the pharmacy professional answers your questions.", are the two aspects that must be improved to achieve a higher degree of satisfaction.
KEYWORDS
Satisfaction, Users, Customer Service, Pharmacotherapy Monitoring, Community Pharmacie
A Remark on Lorentz Violation at Finite Temperature
We investigate the radiatively induced Chern-Simons-like term in
four-dimensional field theory at finite temperature. The Chern-Simons-like term
is temperature dependent and breaks the Lorentz and CPT symmetries. We find
that this term remains undetermined although it can be found unambiguously in
different regularization schemes at finite temperature.Comment: To appear in JHEP, 8 pages, 1 eps figure, minor changes and
references adde
Methyl Ester Functionalized Phenalenyl Arene- and Bipyridine-Ruthenium-Based Complexes for Electroactive Langmuir-Blodgett Films
We report the synthesis of a new phenalenyl ligand, functionalized with a methyl ester electron withdrawing group, named 9-hydroxy-1-oxo-1H-phenalen-5-methyl carboxylate (L), and the generated complexes [Ru(bpy)2L]PF6 and [(η6-C6H6)Ru(L)Cl]. Compounds were characterized by spectroscopic and X-ray diffraction methods, and their electrochemical behavior was investigated via cyclic voltammetry and UV-vis spectroelectrochemistry. The one-electron oxidized compounds have an unpaired electron located in the phenalenyl ring, as supported by theoretical calculations (DFT) and EPR results. Langmuir-Blodgett (LB) films deposited by [Ru(bpy)2L]2+/3+ species mixed with stearic acid are electroactive, showing a quasi-reversible wave with E1/2Film1 = 0.74 V and E1/2Film2 = 0.81, which are promising systems that allow access to immobilized open-shell species in the film
Quantifying sub-elite youth football weekly training load and recovery variation
Monitoring the training load in football is an important strategy to improve athletic performance and an effective training periodization. The aim of this study was two-fold: (1) to quantify the weekly training load and recovery status variations performed by under-15, under-17 and under-19 sub-elite young football players; and (2) to analyze the influence of age, training day, weekly microcycle, training and playing position on the training load and recovery status. Twenty under-15, twenty under-17 and twenty under-19 players were monitored over a 2-week period during the first month of the 2019-2020 competitive season. Global positioning system technology (GPS) was used to collect external training loads: total distance covered, average speed, maximal running speed, relative high-speed running distance, high metabolic load distance, sprinting distance, dynamic stress load, accelerations and decelerations. Internal training load was monitored using ratings of perceived exertion (RPE) and session rating of perceived exertion (sRPE). Recovery status was obtained using the total quality recovery (TQR) scale. The results show an age-related influence for external training load (p <= 0.001; d = 0.29-0.86; moderate to strong effect), internal training load (p <= 0.001, d = 0.12-0.69; minimum to strong effect) and recovery status (p <= 0.001, d = 0.59; strong effect). The external training load presented differences between training days (p < 0.05, d = 0.26-0.95; moderate to strong effect). The playing position had a minimum effect on the weekly training load (p < 0.05; d = 0.06-0.18). The weekly microcycle had a moderate effect in the TD (p < 0.05, d = 0.39), RPE (p < 0.05; d = 0.35) and sRPE (p < 0.05, d = 0.35). Interaction effects were found between the four factors analyzed for deceleration (F = 2.819, p = 0.017) and between inter-day, inter-week and age for total covered distance (F = 8.342, p = 0.008). This study provided specific insights about sub-elite youth football training load and recovery status to monitor training environments and load variations. Future research should include a longer monitoring period to assess training load and recovery variations across different season phases.This research was supported by the Douro Higher Institute of Educational Sciences and the Portuguese Foundation for Science and Technology, I.P. (project UIDB04045/2021).
Documentinfo:eu-repo/semantics/publishedVersio
Effects of match location, quality of opposition and match outcome on match running performance in a Portuguese professional football team
The aim of this study was to analyze the effects of match location, quality of opposition and match outcome on match running performance according to playing position in a Portuguese professional football team. Twenty-three male professional football players were monitored from eighteen Portuguese Football League matches during the 2019–2020 season. Global positioning system technology (GPS) was used to collect time-motion data. The match running performance was obtained from five playing positions: central defenders (CD), fullbacks (FB), central midfielders (CM), wide midfielders (WM) and forwards (FW). Match running performance was analyzed within specific position and contextual factors using one-way analysis of variance (ANOVA) for repeated measures, standardized (Cohen) differences and smallest worthwhile change. CM and WM players covered significantly greater total distance (F = 15.45, p = 0.000, η2 = 0.334) and average speed (F = 12.79, p < 0.001, η2 = 0.294). WM and FB players covered higher distances at high-speed running (F = 16.93, p = 0.000, η2 = 0.355) and sprinting (F = 13.49; p < 0.001, η2 = 0.305). WM players covered the highest number of accelerations (F = 4.69, p < 0.001, η2 = 0.132) and decelerations (F = 12.21, p < 0.001, η2 = 0.284). The match running performance was influenced by match location (d = 0.06–2.04; CI: −0.42–2.31; SWC = 0.01–1.10), quality of opposition (d = 0.13–2.14; CI: –0.02–2.60; SWC = 0.01–1.55) and match outcome (d = 0.01–2.49; CI: −0.01–2.31; SWC = 0.01–0.35). Contextual factors influenced the match running performance with differential effects between playing positions. This study provides the first report about the contextual influence on match running performance in a Portuguese professional football team. Future research should also integrate tactical and technical key indicators when analyzing the match-related contextual influence on match running performanceThis research was supported by the Douro Higher Institute of Educational Sciences and the Portuguese Foundation for Science and Technology, I.P. (project UIDB04045/2021)info:eu-repo/semantics/publishedVersio
The narrative model of therapeutic change: an exploratory study tracking innovative moments and protonarratives using state space grids
Despite the popularity of narrative approaches to the change in psychotherapy, a better understanding of how narrative transformation facilitates therapeutic change is needed. Research on innovative moments (IMs) has explored how IMs in psychotherapy evolve over time. We expand on past studies by exploring how IMs become aggregated in narrative threads, termed protonarratives, which come to constitute an alternative self-narrative at the conclusion of therapy. The results suggest that the good outcome case had a different pattern of IM integration within protonarratives, revealing greater flexibility than the poor outcome case. These results support the heuristic value of the concept of the protonarrative
Scaffolding strategies for tissue engineering and regenerative medicine applications
During the past two decades, tissue engineering and the regenerative medicine field have invested in the regeneration and reconstruction of pathologically altered tissues, such as cartilage, bone, skin, heart valves, nerves and tendons, and many others. The 3D structured scaffolds and hydrogels alone or combined with bioactive molecules or genes and cells are able to guide the development of functional engineered tissues, and provide mechanical support during in vivo implantation. Naturally derived and synthetic polymers, bioresorbable inorganic materials, and respective hybrids, and decellularized tissue have been considered as scaffolding biomaterials, owing to their boosted structural, mechanical, and biological properties. A diversity of biomaterials, current treatment strategies, and emergent technologies used for 3D scaffolds and hydrogel processing, and the tissue-specific considerations for scaffolding for Tissue engineering (TE) purposes are herein highlighted and discussed in depth. The newest procedures focusing on the 3D behavior and multi-cellular interactions of native tissues for further use for in vitro model processing are also outlined. Completed and ongoing preclinical research trials for TE applications using scaffolds and hydrogels, challenges, and future prospects of research in the regenerative medicine field are also presented.This research was funded by Norte Portugal Regional Operational Programme (NORTE 2020),
under the PORTUGAL 2020 Partnership Agreement, through the European Regional Development Fund
(ERDF) (NORTE-01-0145-FEDER-000023) and by the Portuguese Foundation for Science and Technology
((M-ERA-NET/0022/2016), Transitional Rule DL 57/2016 (CTTI-57/18-I3BS(5)), and (IF/01285/2015))
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