Three flavor neutrino oscillations in matter

We derive analytic expressions for three flavor neutrino oscillations in the presence of matter in the plane wave approximation using the Cayley-Hamilton formalism. Especially, we calculate the time evolution operator in both flavor and mass bases. Furthermore, we find the transition probabilities, matter mass squared differences, and matter mixing angles all expressed in terms of the vacuum mass squared differences, the vacuum mixing angles, and the matter density. The conditions for resonance in the presence of matter are also studied in some examples.Comment: 25 pages, 6 figures (PostScript), RevTe

Multiresolution FIR neural-network-based learning algorithm applied to network traffic prediction

Published versio

New World Stephanocampta (Hymenoptera: Mymaridae)—descriptions of a new species from Argentina and of the male of S. masoni

The genus Stephanocampta Mathot (Hymenoptera: Mymaridae) includes only two previously described species, S. yaosekoensis Mathot from the Democratic Republic of the Congo (Mathot 1966) and S. masoni (Yoshimoto) from Costa Rica and Panama (Yoshimoto 1990). Here we describe and illustrate a new species from Argentina based on a female, illustrate both sexes and newly describe the male of S. masoni, and provide a key to differentiate females of the three species.Fil: Aquino, Daniel Alejandro. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Universidad Nacional de La Plata. Facultad de Ciencias Naturales y Museo. División Entomología; ArgentinaFil: Triapitsyn, Serguei V.. University of California; Estados Unido

Improved decision for a resource-efficient fusion scheme in cooperative spectrum sensing

Paper presented at at 2015 International Workshop on Telecommunications (IWT), 14th to 17th of June, Santa Rita do Sapucai, Brazil. Abstract Recently, a novel decision fusion scheme for cooperative spectrum sensing was proposed, aiming at saving resources in the reporting channel transmissions. Secondary users are allowed to report their local decisions through the symbols of binary modulations, at the same time and with the same carrier frequencies. As a consequence, the transmitted symbols add incoherently at the fusion center, forming a larger set of symbols in which a subset is associated to the presence of the primary signal, and another subset is associated to the absence of such a signal. A Bayesian decision criterion with uniform prior was applied for discriminating these subsets. In this paper we propose a modified decision rule in which the target probabilities of detection and false alarm are taken into account to produce a large performance improvement over the original decision criterion. This improvement comes with practically no cost in complexity and does not demand the knowledge of any additional information when compared to the original rule

Executive functions in insomnia disorder: a systematic review and exploratory meta-analysis

Background: Executive functions (EFs) are involved in the control of basic psychological processes such as attention and memory and also contribute to emotion regulation. Research on the presence of EFs impairments in insomnia yielded inconsistent results. Therefore, we performed a systematic review of the literature on three EFs: inhibitory control, working memory, and cognitive flexibility in adults with insomnia in order to investigate the presence and magnitude of insomnia-related EFs impairments. Methods: PubMed, Scopus, Medline, and PsycINFO were searched. Risk of bias assessment of included studies was performed by two independent researchers. Findings were summarised using both a narrative approach and meta-analysis. Cohen’s d was calculated at 95% confidence interval (CI) as effect size of between groups differences. Results: Twenty-eight studies comparing adult individuals with a diagnosis of insomnia and healthy controls on neuropsychological measures of EFs were included. Narrative synthesis revealed substantial variability across study findings. Factors that were primarily hypothesised to account for this variability are: objective sleep impairments and test sensitivity. Exploratory meta-analysis showed impaired performance of small to moderate magnitude in individuals with insomnia as compared to controls in reaction times, but not accuracy rates, of inhibitory control (d = −0.32, 95% CI: −0.52 to −0.13) and cognitive flexibility tasks (d = −0.30, 95% CI: −0.59 to −0.01). Performance in working memory tasks was also significantly impacted (d = −0.19, 95% CI: −0.38 to −0.00). Effects sizes were larger when insomnia was associated with objective sleep impairments, rather than normal sleep. Conclusions: We gathered evidence supporting small to moderate deficits in EFs in individuals with insomnia. Due to the small sample size results should be considered preliminary and interpreted carefully

Dynamics of Natural Killer cell receptor revealed by quantitative analysis of photoswitchable protein

Natural Killer (NK) cell activation is dynamically regulated by numerous activating and inhibitory surface receptors that accumulate at the immune synapse. Quantitative analysis of receptor dynamics has been limited by methodologies which rely on indirect measurements such as fluorescence recovery after photobleaching. Here, we report a novel approach to study how proteins traffic to and from the immune synapse using NK cell receptors tagged with the photoswitchable fluorescent protein tdEosFP, which can be irreversibly photoswitched from a green to red fluorescent state by ultraviolet light. Thus, following a localized switching event, the movement of the photoswitched molecules can be temporally and spatially resolved by monitoring fluorescence in two regions of interest. By comparing images with mathematical models, we evaluated the diffusion coefficient of the receptor KIR2DL1 (0.23 +- 0.06 micron^2/s) and assessed how synapse formation affects receptor dynamics. Our data conclude that the inhibitory NK cell receptor KIR2DL1 is continually trafficked into the synapse and remains surprisingly stable there. Unexpectedly however, in NK cells forming synapses with multiple target cells simultaneously, KIR2DL1 at one synapse can relocate to another synapse. Thus, our results reveal a previously undetected inter-synaptic exchange of protein.Comment: 25 pages, 5 figure

A massa dos neutrinos. Teoria versus experimento.

Nas últimas décadas, soluções ao problema do neutrino solar têm sido investigadas no contexto de teorias nas quais os neutrinos têm massa e podem oscilar entre os sabores eletrônico, muônico e tauônico. Os dados experimentais, hoje, parecem indicar que os neutrinos têm massa e que oscilações entre sabores realmente acontecem. No presente trabalho, efetuaremos uma revisão geral sobre a física de neutrinos desde a época da proposta de sua existência, apresentaremos suas propriedades e uma breve discussão das interações entre neutrinos e as outras partículas elementares no contexto do modelo padrão das interações fundamentais. Uma visão geral dos principais mecanismos de produção de neutrinos no interior solar, o espectro de energia destes neutrinos, os métodos de detecção de neutrinos e as características dos principais detectores existentes serão apresentados. No contexto de teorias envolvendo neutrinos massivos, mostraremos como o fluxo de neutrinos solares pode ser afetado devido a oscilações entre sabores de neutrinos. Alguns dados experimentais e as conclusões que podemos tirar do confronto entre estes dados e a hipótese de oscilações entre sabores serão também apresentados

Effect of the 24 September 2011 solar radio burst on precise point positioning service

An intense solar radio burst occurred on 24 September 2011, which affected the tracking of Global Navigation Satellite Systems’ (GNSS) signals by receivers located in the sunlit hemisphere of the Earth. This manuscript presents for the first time the impacts of this radio burst on the availability of Fugro’s real-time precise point positioning service for GNSS receivers and on the quality of the L band data link used to broadcast this service. During the peak of the radio burst (12:50–13:20 UT), a reduction in the L band signal-to-noise ratio (SNR) is observed. For some receiver locations, a reset in the position filter is observed, which can be either due to the reduction in the L band SNR or the reduction in the number of tracked GNSS satellites. This reset in the position filter is accompanied by degradation in the positioning accuracy, which is also discussed herein