160 research outputs found

    Neutrino Target-of-Opportunity Sky Coverage and Scheduler for EUSO-SPB2

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    Very-high-energy neutrinos can be observed by detecting air shower signals. Detection of transient target of opportunity (ToO) neutrino sources is part of a broader multimessenger program. The Extreme Universe Space Observatory on a Super Pressure Balloon 2 (EUSO-SPB2) Mission, launched on May 12, 2023, was equipped with an optical Cherenkov Telescope (CT) designed to detect up-going air showers sourced by Earth-skimming neutrinos that interact near the Earth's limb. Presented here is an overview of the sky coverage and ToO scheduler software for EUSO-SPB2. By using the balloon trajectory coordinates and setting constraints on the positions of the Sun and Moon to ensure dark skies, we can determine if and when a source direction is slightly below the Earth's limb. From a source catalog, CT scheduling and pointing is performed to optimize the search for high-energy neutrinos coming from astrophysical sources. Some sample results for EUSO-SPB2 are shown.Comment: 10 pages, 6 figures, ICRC2023 Conference Proceeding

    A narrative synthesis of women's out-of-body experiences during childbirth

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    Introduction Some women have a dissociated, out-of-body experience (OBE) during childbirth, which may be described as seeing the body from above or floating above the body. This review examines this phenomenon using narratives from women who have experienced intrapartum OBEs. Methods A narrative synthesis of qualitative research was employed to systematically synthesize OBE narratives from existing studies. Strict inclusion and exclusion criteria were applied. The included papers were critiqued by 2 of the authors to determine the appropriateness of the narrative synthesis method, procedural transparency, and soundness of the interpretive approach. Results Women experiencing OBEs during labor and birth report a disembodied state in the presence of stress or trauma. Three forms of OBEs are described: floating above the scene, remaining close to the scene, or full separation of a body part from the main body. Women had clear recall of OBEs, describing the experience and point of occurrence. Women who reported OBEs had experienced current or previous traumatic childbirth, or trauma in a non-birth situation. OBEs as prosaic experiences were not identified. Discussion OBEs are part of the lived experience of some women giving birth. The OBEs in this review were trauma related with some women disclosing previous posttraumatic stress disorder (PTSD). It is not evident whether there is a connection between PTSD and OBEs at present, and OBEs may serve as a potential coping mechanism in presence of trauma. Clinicians should legitimize women’s disclosure of OBEs and explore and ascertain their impact, either as a normal coping mechanism or a precursor to perinatal mental illness. Research into the function of OBEs and any relationship to PTSD may assist in early interventions for childbearing women

    Method Families Concept: Application to Decision-Making Methods

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    International audienceThe role of variability in Software engineering grows increasingly as it allows developing solutions that can be easily adapted to a specific context and reusing existing knowledge. In order to deal with variability in the method engineering (ME) domain, we suggest applying the notion of method families. Method components are organized as a method family, which is configured in the given situation into a method line. In this paper, we motivate the concept of method families by comparing the existing approaches of ME. We detail then the concept of method families and illustrate it with a family of decision-making (DM) methods that we call MADISE

    Improving model construction of profile HMMs for remote homology detection through structural alignment

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    <p>Abstract</p> <p>Background</p> <p>Remote homology detection is a challenging problem in Bioinformatics. Arguably, profile Hidden Markov Models (pHMMs) are one of the most successful approaches in addressing this important problem. pHMM packages present a relatively small computational cost, and perform particularly well at recognizing remote homologies. This raises the question of whether structural alignments could impact the performance of pHMMs trained from proteins in the <it>Twilight Zone</it>, as structural alignments are often more accurate than sequence alignments at identifying motifs and functional residues. Next, we assess the impact of using structural alignments in pHMM performance.</p> <p>Results</p> <p>We used the SCOP database to perform our experiments. Structural alignments were obtained using the 3DCOFFEE and MAMMOTH-mult tools; sequence alignments were obtained using CLUSTALW, TCOFFEE, MAFFT and PROBCONS. We performed leave-one-family-out cross-validation over super-families. Performance was evaluated through ROC curves and paired two tailed t-test.</p> <p>Conclusion</p> <p>We observed that pHMMs derived from structural alignments performed significantly better than pHMMs derived from sequence alignment in low-identity regions, mainly below 20%. We believe this is because structural alignment tools are better at focusing on the important patterns that are more often conserved through evolution, resulting in higher quality pHMMs. On the other hand, sensitivity of these tools is still quite low for these low-identity regions. Our results suggest a number of possible directions for improvements in this area.</p

    A Family of Chemoreceptors in Tribolium castaneum (Tenebrionidae: Coleoptera)

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    Chemoperception in invertebrates is mediated by a family of G-protein-coupled receptors (GPCR). To date nothing is known about the molecular mechanisms of chemoperception in coleopteran species. Recently the genome of Tribolium castaneum was sequenced for use as a model species for the Coleoptera. Using blast searches analyses of the T. castaneum genome with previously predicted amino acid sequences of insect chemoreceptor genes, a putative chemoreceptor family consisting of 62 gustatory receptors (Grs) and 26 olfactory receptors (Ors) was identified. The receptors have seven transmembrane domains (7TMs) and all belong to the GPCR receptor family. The expression of the T. castaneum chemoreceptor genes was investigated using quantification real- time RT-PCR and in situ whole mount RT-PCR analysis in the antennae, mouth parts, and prolegs of the adults and larvae. All of the predicted TcasGrs were expressed in the labium, maxillae, and prolegs of the adults but TcasGr13, 19, 28, 47, 62, 98, and 61 were not expressed in the prolegs. The TcasOrs were localized only in the antennae and not in any of the beetles gustatory organs with one exception; the TcasOr16 (like DmelOr83b), which was localized in the antennae, labium, and prolegs of the beetles. A group of six TcasGrs that presents a lineage with the sugar receptors subfamily in Drosophila melanogaster were localized in the lacinia of the Tribolium larvae. TcasGr1, 3, and 39, presented an ortholog to CO2 receptors in D. melanogaster and Anopheles gambiae was recorded. Low expression of almost all of the predicted chemoreceptor genes was observed in the head tissues that contain the brains and suboesophageal ganglion (SOG). These findings demonstrate the identification of a chemoreceptor family in Tribolium, which is evolutionarily related to other insect species

    Amino Acid Residues Contributing to Function of the Heteromeric Insect Olfactory Receptor Complex

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    Olfactory receptors (Ors) convert chemical signals—the binding of odors and pheromones—to electrical signals through the depolarization of olfactory sensory neurons. Vertebrates Ors are G-protein-coupled receptors, stimulated by odors to produce intracellular second messengers that gate ion channels. Insect Ors are a heteromultimeric complex of unknown stoichiometry of two seven transmembrane domain proteins with no sequence similarity to and the opposite membrane topology of G-protein-coupled receptors. The functional insect Or comprises an odor- or pheromone-specific Or subunit and the Orco co-receptor, which is highly conserved in all insect species. The insect Or-Orco complex has been proposed to function as a novel type of ligand-gated nonselective cation channel possibly modulated by G-proteins. However, the Or-Orco proteins lack homology to any known family of ion channel and lack known functional domains. Therefore, the mechanisms by which odors activate the Or-Orco complex and how ions permeate this complex remain unknown. To begin to address the relationship between Or-Orco structure and function, we performed site-directed mutagenesis of all 83 conserved Glu, Asp, or Tyr residues in the silkmoth BmOr-1-Orco pheromone receptor complex and measured functional properties of mutant channels expressed in Xenopus oocytes. 13 of 83 mutations in BmOr-1 and BmOrco altered the reversal potential and rectification index of the BmOr-1-Orco complex. Three of the 13 amino acids (D299 and E356 in BmOr-1 and Y464 in BmOrco) altered both current-voltage relationships and K+ selectivity. We introduced the homologous Orco Y464 residue into Drosophila Orco in vivo, and observed variable effects on spontaneous and evoked action potentials in olfactory neurons that depended on the particular Or-Orco complex examined. Our results provide evidence that a subset of conserved Glu, Asp and Tyr residues in both subunits are essential for channel activity of the heteromeric insect Or-Orco complex

    Computational Model of the Insect Pheromone Transduction Cascade

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    A biophysical model of receptor potential generation in the male moth olfactory receptor neuron is presented. It takes into account all pre-effector processes—the translocation of pheromone molecules from air to sensillum lymph, their deactivation and interaction with the receptors, and the G-protein and effector enzyme activation—and focuses on the main post-effector processes. These processes involve the production and degradation of second messengers (IP3 and DAG), the opening and closing of a series of ionic channels (IP3-gated Ca2+ channel, DAG-gated cationic channel, Ca2+-gated Cl− channel, and Ca2+- and voltage-gated K+ channel), and Ca2+ extrusion mechanisms. The whole network is regulated by modulators (protein kinase C and Ca2+-calmodulin) that exert feedback inhibition on the effector and channels. The evolution in time of these linked chemical species and currents and the resulting membrane potentials in response to single pulse stimulation of various intensities were simulated. The unknown parameter values were fitted by comparison to the amplitude and temporal characteristics (rising and falling times) of the experimentally measured receptor potential at various pheromone doses. The model obtained captures the main features of the dose–response curves: the wide dynamic range of six decades with the same amplitudes as the experimental data, the short rising time, and the long falling time. It also reproduces the second messenger kinetics. It suggests that the two main types of depolarizing ionic channels play different roles at low and high pheromone concentrations; the DAG-gated cationic channel plays the major role for depolarization at low concentrations, and the Ca2+-gated Cl− channel plays the major role for depolarization at middle and high concentrations. Several testable predictions are proposed, and future developments are discussed
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