111,971 research outputs found
Theoretical predictions for dark matter detection in dwarf irregular galaxies with gamma rays
No full textWe investigate rotationally supported dwarf irregular (DIRR) galaxies as a new category of targets for indirect dark matter (DM) searches with gamma-ray telescopes. In the framework of pointlike analysis, pressure-supported dwarf spheroidal (DSPH) galaxies are usually considered as one of the best categories of targets for indirect DM searches, due to their close distance and negligible astrophysical background. Nonetheless, as a result of their uncertain kinematics, the DM content and astrophysical J-factors of DSPHs are usually affected by significant errors. In this paper, we study a sample of 36 DIRRs as prospective targets of interest. In the framework of the universal rotation curve, the kinematics of DIRR galaxies provides a good estimation of their DM halo density distribution and, consequently, of their astrophysical J-factors. We calculate the J-factors for these 36 DIRR galaxies, whose kinematics have been studied in a previous work. We find a range of values comparable with the J-factors of DSPH galaxies. However, differently from DSPHs an extra astrophysical gamma-ray background component is expected in DIRR galaxies, that is due to their star-formation activity. In this paper, we show via a theoretical approach that for galaxies in our sample the extra astrophysical background component is negligible. Therefore, we conclude that DIRR galaxies can be potentially considered as additional pointlike targets for DM searches with gamma rays. As a first application of this study, we show the sensitivity limits of the Fermi-LAT telescope to these objects and we calculate constraints on the DM particle mass and annihilation cross section. We conclude that the results of the individual study of several DIRR galaxies are not yet competitive with respect to the analysis of one of the most promising DSPH galaxies, i.e., SEGUE1. However, taking into account SEGUE1's symmetry-related uncertainties in the J-factor calculation might alter this conclusion. Additionally, we calculate constraints for the combined analysis of the seven most promising DIRR galaxies of our sample
author-bios-SRD-19-0063.R1 – Supplemental material for The Network Structure of Police Misconduct
No full textSupplemental material, author-bios-SRD-19-0063.R1 for The Network Structure of Police Misconduct by George Wood, Daria Roithmayr and Andrew V. Papachristos in Socius</p
Going Beyond Counting First Authors in Author Co-citation Analysis
No full textThe 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
Constraints on cross-section and lifetime of dark matter with HAWC Observations of dwarf Irregular galaxies
No full textIt has been shown that the dynamics of dwarf Irregular (dIrr) galaxies are dominated by dark matter. It is also observed that these galaxies have low star formation rates and metallicities, and no gamma-ray emission at ultra very high energies is expected. Because of their distance, dark matter content and vast number, dIrr galaxies are good targets to perform indirect dark matter searches by ground-based and wide field of view gamma-ray experiments, like HAWC. We analyzed data at the position of 31 dIrr galaxies within the HAWC field-of-view and no significant excess was found. Here, we present the individual and combined limits on the annihilation cross-section and decay lifetime of weakly interacting massive particles with mass between 1 and 100 TeV
Variations on the Author
No full text“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
Standardized anesthetic protocol in pediatric Radiotherapy: A retrospective analysis of clinical efficacy and outcomes
No full textBackground and purpose: Radiotherapy plays a critical role in the treatment of pediatric cancers; however, the need for absolute immobilization during treatment necessitates the use of general anesthesia or deep sedation.
Materials and methods: In this retrospective observational study conducted at Salerno University Hospital between 2022 and 2024, we evaluated a standardized anesthetic protocol based on the exclusive use of a laryngeal mask airway (LMA) in pediatric patients undergoing radiotherapy. Data were collected from 420 anesthesia sessions performed in 22 patients under 14 years of age with solid or hematological tumors. The protocol involved premedication with midazolam when indicated, induction with either intravenous propofol (administered in 77.3 % of sessions with a mean dose of 1.64 mg/kg) or inhalational sevoflurane (in 22.7 % of sessions), and maintenance with sevoflurane at a mean minimum alveolar concentration of 2.2. Continuous monitoring of vital parameters was ensured via advanced remote systems, while airway management was successfully maintained with LMA in all sessions.
Results: The overall complication rate was low (1.9%), with laryngospasm (0.95%), postoperative delirium (0.71%), and a single episode of tachycardia/hypotension (0.24%) observed; importantly, no major adverse events occurred. The median time to awakening was 3 min, and full recovery in the post-anesthesia care unit was achieved within 35 min.
Conclusion: These findings suggest that the standardized anesthetic protocol is both safe and effective, ensuring rapid recovery and minimal complications, thereby optimizing the management of pediatric radiotherapy sessions
Unveiling of the AS-NMD-mediated regulation of Peptide/Histidine Transporter 1 (SLC15A4/PHT1) gene products under physiological or inflammatory challenges
No full textIn vertebrates, the SLC15A4 gene codes for the peptide/histidine transporter 1 (PHT1) protein, which transport activity of di-/tripeptides and histidine across plasma and subcellular membranes has been generally described [1]. Recently, several studies have pointed out that the human SLC15A4 gene codes for a late endosome/lysosome carrier taking part in TLR7-, TLR9-, and NOD1-mediated pathways, thus putatively involved in inflammatory, immune and autoimmune diseases. Accordingly, SLC15A4/PHT1 altered activity has been associated to conditions such as type 2 diabetes, inflammatory bowel diseases (IBD) and systemic lupus erythematosus [2]. In mammals, the Slc15a4 genes are abundantly expressed by immune and nervous cells, in which they undergo alternative splicing (AS) events which physiological meaning is still unknown. Here, we report of a unique SLC15A4/PHT1 AS-mediated regulation which we found conserved from zebrafish to human. We show that this regulation is physiologically facilitated by the Nonsense-Mediated mRNA Decay (NMD) surveillance pathway, in human nervous-derived and immune-derived cells too; in these latter, both the canonical and AS variants are sensitive to inflammatory molecular triggers. Furthermore, in an IBD murine model, we show that GI inflammation seems to differentially affect the expression levels of the alternative SLC15A4/PHT1 gene products in different GI tracts. Overall, by unveiling the AS-NMD-mediated gene regulation, our findings might introduce a key analytical element for stepping forward the comprehension of the mechanism of intervention of SLC15A4/PHT1 in inflammatory and immune processes. [1] Verri T, Barca A, et al. (2017) Di- and tripeptide transport in vertebrates: the contribution of teleost fish models. J Comp Physiol B. 187(3):395-462. [2] Griffith AD, Zaidi AK, et al. (2018) A requirement for slc15a4 in imiquimod-induced systemic inflammation and psoriasiform inflammation in mice. Sci Rep. 8(1):14451
Dark Matter search in dwarf irregular galaxies with the Fermi Large Area Telescope
No full textWe analyze 11 years of Fermi-LAT data corresponding to the sky regions of 7
dwarf irregular (dIrr) galaxies. DIrrs are dark matter (DM) dominated systems,
proposed as interesting targets for the indirect search of DM with gamma rays.
The galaxies represent interesting cases with a strong disagreement between the
density profiles (core vs. cusp) inferred from observations and numerical
simulations. In this work, we addressed the problem by considering two
different DM profiles, based on both the fit to the rotation curve (in this
case a Burkert cored profile) and results from N-body cosmological simulations
(i.e., NFW cuspy profile). We also include halo substructures in our analysis,
which is expected to boost the DM signal a factor of ten in halos such as those
of dIrrs. For each DM model and dIrr, we create a spatial template of the
expected DM-induced gamma-ray signal to be used in the analysis of Fermi-LAT
data. No significant emission is detected from any of the targets in our
sample. Thus, we compute upper limits on the DM annihilation cross-section
versus mass parameter space. Among the 7 dIrrs, we find IC10 and NGC6822 to
yield the most stringent individual constraints, independently of the adopted
DM profile. We also produce combined DM limits for all objects in the sample,
which turn out to be dominated by IC10 for all DM models and annihilation
channels, i.e. , and . The strongest
constraints are obtained for and are at the level of at
GeV. Though these limits are a factor of 3 higher than the thermal relic cross
section at low WIMP masses, they are independent from and complementary to
those obtained by means of other targets.Comment: 19 pages, 9 figures, Accepted for Publication in PR
On the possible enhancement of the dark matter density distribution at the galactic center
No full textThe dark matter spike induced by the adiabatic growth of a massive black hole
in a cuspy environment, may explain the thermal dark matter density required to
fit the cut-off in the HESSJ1745-290 gamma-ray spectra as TeV dark matter
signal with a background component. The spike extension appears comparable with
the HESS angular resolution
Využití sociálních médií v B2B prodeji
No full textTato diplomová práce se zabývá tím, jak mohou B2B obchodníci využívat sociální média v prodeji. Na základě systematické rešerše literatury, autor zjistil, že akademici, zkoumající danou problematiku, navrhují další výzkum, a to: v kterých konkrétních krocích se dají využít sociální média v prodeji (Salo, 2017). Autor se na základě toho rozhodl zjistit, jaké sociální sítě, různé technologie a pluginy se dají využít v B2B prodeji - tzv. social sellingu. Social selling se v této práci týká primárně procesu akvizice a okrajově péčí o stávající zákazníky. Autor si vybral kvalitativní průzkum pomocí 10 hloubkových polo-strukturovaných rozhovorů, aby odhalil jak, která sociální média to jsou, tak i motivaci prodejců, proč tato média používat/nepoužívat. Aby autor dodržel správnost vyhodnocení výsledků, data byla analyzována pomocí Tématické analýzy, která v této studii vykrystalizovala 2 hlavní strategické přístupy v social sellingu. Tyto přístupy (tzv. Push a Pull strategie) obsahují praktické příklady a konkrétní aktivity, které mohou prodejci využívat v každodenní praxi. Tyto výsledky jsou prezentovány s důrazem na praktičnost a jednoduchost implementace. Tvoří proto hlavní přínos autorovo výzkumu. V poslední části autor zmiňuje výzvy a manažerská doporučení, které mohou obchodníci využít v každodenním pracovním životě.This diploma thesis focuses on social media usage in B2B sales. Based on the systematic literature review conducted by the author, he has found out that recent researchers (Salo, 2017) suggest further research in the area of how and in which sales phase should various social networking sites, technologies and plugins used. To further fill this research gap, author decided to identify these social media and their usage among B2B salespeople in the so-called social selling process. The social selling process in this thesis applies mainly to acquiring new prospects and tangentially to taking care of existing clients (follow-up step). Author has chosen a qualitative research method via conducting 10 in-depth semi-structured interviews to reveal these instruments as well as motivation of a sales person on why to use social media in the selling process. The collected data was analyzed using Thematic analysis to ensure the right procedure and to identify main themes which crystalized into 2 main strategic approaches in social selling. These approaches (Push and Pull) include practical examples of concrete activities which sales people can use in their daily jobs and are presented with focus on practicality and ease of implementation. These also form the main contribution of author`s research. In the last part, author mentions challenges in social selling and recommended managerial implications for salesforce
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