Tests of CPT and Lorentz symmetry from muon anomalous magnetic dipole moment

We derive the relativistic factor for splitting of the $g$-factors of a fermion and its anti-fermion partner, which is important for placing constraints on dimension-5, $CPT$-odd and Lorentz-invariance-violating interactions from experiments performed in a cyclotron. From existing data, we extract limits (1$\sigma$) on the coupling strengths of the temporal component, $f^0$, of a background field (including the field amplitude), which is responsible for such $g$-factor splitting, with an electron, proton, and muon: $|f^0_e|< 2.3 \times 10^{-12} ~\mu_{\textrm{B}}$, $|f^0_p|< 4 \times 10^{-9} ~\mu_{\textrm{B}}$, and $|f^0_\mu|< 8 \times 10^{-11} ~\mu_{\textrm{B}}$, respectively, in the laboratory frame. From existing data, we also extract limits on the coupling strengths of the spatial components, $d^{\perp}$, of related dimension-5 interactions of a background field with an electron, proton, neutron, and muon: $| {d}_e^{\perp} | \lesssim 10^{-9} ~\mu_{\textrm{B}}$, $| {d}_p^{\perp} | \lesssim 10^{-9} ~\mu_{\textrm{B}}$, $| {d}_n^{\perp} | \lesssim 10^{-10} ~\mu_{\textrm{B}}$, and $| {d}_\mu^{\perp} | \lesssim 10^{-9} ~\mu_{\textrm{B}}$, respectively, in the laboratory frame.Comment: 6 pages. Minor corrections and new references adde

Searching for Scalar Dark Matter in Atoms and Astrophysical Phenomena: Variation of Fundamental Constants

We propose to search for scalar dark matter via its effects on the electromagnetic fine-structure constant and particle masses. Scalar dark matter that forms an oscillating classical field produces `slow' linear-in-time drifts and oscillating variations of the fundamental constants, while scalar dark matter that forms topological defects produces transient-in-time variations of the constants of Nature. These variations can be sought for with atomic clock, laser interferometer and pulsar timing measurements. Atomic spectroscopy and Big Bang nucleosynthesis measurements already give improved bounds on the quadratic interaction parameters of scalar dark matter with the photon, electron, and light quarks by up to 15 orders of magnitude, while Big Bang nucleosynthesis measurements provide the first such constraints on the interaction parameters of scalar dark matter with the massive vector bosons.Comment: 4 pages, 1 figure, Contributed to the 11th Patras Workshop on Axions, WIMPs and WISPs, Zaragoza, June 22 to 26, 201

Dark matter scattering on electrons: Accurate calculations of atomic excitations and implications for the DAMA signal

We revisit the WIMP-type dark matter scattering on electrons that results in atomic ionization, and can manifest itself in a variety of existing direct-detection experiments. Unlike the WIMP-nucleon scattering, where current experiments probe typical interaction strengths much smaller than the Fermi constant, the scattering on electrons requires a much stronger interaction to be detectable, which in turn requires new light force carriers. We account for such new forces explicitly, by introducing a mediator particle with scalar or vector couplings to dark matter and to electrons. We then perform state of the art numerical calculations of atomic ionization relevant to the existing experiments. Our goals are to consistently take into account the atomic physics aspect of the problem (e.g., the relativistic effects, which can be quite significant), and to scan the parameter space: the dark matter mass, the mediator mass, and the effective coupling strength, to see if there is any part of the parameter space that could potentially explain the DAMA modulation signal. While we find that the modulation fraction of all events with energy deposition above 2 keV in NaI can be quite significant, reaching ~50%, the relevant parts of the parameter space are excluded by the XENON10 and XENON100 experiments

Bioprospecting for plant and fungus extracts with systemic effect to control the cucumber powdery mildew.

This work was aimed to select plant and fungus extracts showing systemic effect to control the cucumber powdery mildew. For that, ethanolic extracts were obtained from five basidiomycetes and 71 plant species and tested under greenhouse conditions. Cucumber plants cv. 'Safira' were sprayed with extracts at the first true leaf growth stage and inoculated with Sphaerotheca fuliginea at the second leaf growth stage. The number, diameter and sporulation rate of powdery mildew colonies were evaluated 6 days after inoculation. In an initial screening phase, the extracts of the following plants and fungi revealed some systemic effect against the powdery mildew: Aloe vera (aloe), Bidens pilosa, Ganoderma sp. (basidiomycete), Hyptis crenata, Mascagania betbamiana, Ocotea suaveolens, Oudemansiella canarii (basidiomycete), Pinus taeda (pine), Riehardia grandiflora and Vernonia polyanthes. They were compared in three other experiments and those from Oudemansiella, Ganoderma, pine needles and aloe leaves were the most efficient reducing the number of colonies on the secondary leaf by 79, 65, 30 and 21 %, respectively. Extracts from fruiting bodies of Oudemansiella and Ganoderma also decreased the diameter of colonies by 20 % as well as the sporulation rate by 45 and 70 %, respectively. While Ganoderma did not show any direct effect in vitro, the extract of Oudemansiella (60 mg fresh weight ml[-1]) reduced the germination of powdery mildew conidia at 48 h after inoculation by 71 %. Furthermore, Oudemansiella-extract strongly inhibited the mycelium growth of Cladosporium oxysporum in liquid medium. The possible modes of action of these extracts are discussed

Limiting P-odd interactions of cosmic fields with electrons, protons and neutrons

We propose methods for extracting limits on the strength of P-odd interactions of pseudoscalar and pseudovector cosmic fields with electrons, protons and neutrons. Candidates for such fields are dark matter (including axions) and dark energy, as well as several more exotic sources described by standard-model extensions. Calculations of parity nonconserving amplitudes and atomic electric dipole moments induced by these fields are performed for H, Li, Na, K, Rb, Cs, Ba+, Tl, Dy, Fr, and Ra+. From these calculations and existing measurements in Dy, Cs and Tl, we constrain the interaction strengths of the parity-violating static pseudovector cosmic field to be 7*10^(-15) GeV with an electron, and 3*10^(-8) GeV with a proton.Comment: 6 pages, 1 figur

Parity-violating interactions of cosmic fields with atoms, molecules, and nuclei: Concepts and calculations for laboratory searches and extracting limits

We propose methods and present calculations that can be used to search for evidence of cosmic fields by investigating the parity-violating effects, including parity nonconservation amplitudes and electric dipole moments, that they induce in atoms. The results are used to constrain important fundamental parameters describing the strength of the interaction of various cosmic fields with electrons, protons, and neutrons. Candidates for such fields are dark matter (including axions) and dark energy, as well as several more exotic sources described by standard-model extensions. Existing parity nonconservation experiments in Cs, Dy, Yb, and Tl are combined with our calculations to directly place limits on the interaction strength between the temporal component, b_0, of a static pseudovector cosmic field and the atomic electrons, with the most stringent limit of |b_0^e| < 7*10^(-15) GeV, in the laboratory frame of reference, coming from Dy. From a measurement of the nuclear anapole moment of Cs, and a limit on its value for Tl, we also extract limits on the interaction strength between the temporal component of this cosmic field, as well as a related tensor cosmic-field component d_00, with protons and neutrons. The most stringent limits of |b_0^p| < 4*10^(-8) GeV and |d_00^p| < 5*10^(-8) for protons, and |b_0^n| < 2*10^(-7) GeV and |d_00^n| < 2*10^(-7) for neutrons (in the laboratory frame) come from the results using Cs. Axions may induce oscillating P- and T-violating effects in atoms and molecules through the generation of oscillating nuclear magnetic quadrupole and Schiff moments, which arise from P- and T-odd intranuclear forces and from the electric dipole moments of constituent nucleons. Nuclear-spin-independent parity nonconservation effects may be enhanced in diatomic molecules possessing close pairs of opposite-parity levels in the presence of time-dependent interactions.Comment: 18 pages, 3 figures, 4 tables, Editor's Suggestio

Controle da podridão cinzenta da maçã por produtos naturais biologicamente ativos

Indexación: Web of Science; ScieloBiorend SC (chitosan), BC-1000 EC (grapefruit extract plus bioflavonoids) and ECO-100 SC (bioflavonoids plus organic acids, citric phytoalexins, fatty acids, glycerides and sugars), respectively, suppressed grey rot of apple caused by B. cinerea by 80.1%, 79.0% and 76.5% when used as post-harvest treatments under controlled conditions. When applied as combined pre- and post-harvest treatments Biorend SC inhibited fruit rot by 49.9 %, while BC-1000 EC and ECO-100 SC were ineffective. None of the products inhibited fruit rot when applied as pre-harvest treatments under controlled conditions or as post-harvest treatments under commercial conditions. The algal polysaccharide ulvan used in post-harvest treatments suppressed grey rot by 56.0% under controlled conditions, but had no inhibitory effect on combined pre- and post-harvest treatments. The inability of products to activate defense mechanisms (chitinase and peroxidase) of fruits was consistent with the unsuccessful control of rot by pre-harvest treatment. The results suggest that the natural products used have potential for use in integrated management of Botrytis rot when applied after harvest.Biorend SC (quitosana), BC-1000 EC (extrato de toranja mais flavonóides), e ECO-100 SC (bioflavonóides mais ácidos orgânicos, fitoalexinas cítricas, ácidos graxos glicerídeos e açúcares) inibiram em 80,1%, 79,0% e 76,5%, respectivamente, a podridão causada por Botrytis cinerea quando utilizados no tratamento pós-colheita de frutos de maçã sob condições controladas.Tratamento combinado de Biorend SC, com aplicação tanto em pré como no pós-colheita, proporcionou 49,9% de inibição da podridão, enquanto BC-1000 e ECO-100 EC não foram efetivos. Nenhum desses produtos inibiu a podridão cinzenta, quando utilizados em tratamento de pré-colheita em condições controladas ou em tratamento de pós-colheita em condições comerciais. O polissacarídeo algal ulvana, utilizado nos tratamentos de pós-colheita, reduziu em 56% a podridão cinzenta das maçãs em condições controladas, mas não teve efeito inibitório nos tratamentos combinados de pré e pós-colheita. A incapacidade dos produtos em ativar mecanismos de defesa (quitinases e peroxidases) nos frutos, após o tratamento em pré-colheita, foi consistente com a falta de controle da podridão nesse tipo de ensaio. Pelos resultados, sugere-se que os produtos naturais utilizados apresentam potencial para a utilização no manejo integrado da podridão de Botrytis quando aplicados em pós-colheita.http://ref.scielo.org/kcxb9

Statistical analysis of tourism flows between Ukraine and the Baltic Sea Region countries in 2012-2019

This article explores the features and trends in inbound and outbound tourism flows between Ukraine and the Baltic Sea region (BSR) countries in 2012-2019. The research question is whether inbound our outbound tourism prevailed and how visa-free travel to the Schengen Area affected the number of Ukrainians travelling to the Baltic Sea Region. Two data sources were used in the study. These are the Travel and Tourism Competitiveness Index of the World Economic Forum and data from the State Border Guard Service of Ukraine on the number of foreign citizens visiting Ukraine and the number of Ukrainians travelling abroad. The study employs the statistical methods of structural shifts analysis, time series analysis, and graphical visualisation. The findings indicate that Ukrainian outbound tourism was growing steadily over the study period, whilst visa-free travel to the Schengen Area had no statistically significant impact on the number of outbound tourists from Ukraine to the BSR. Outbound tourism flow prevailed over inbound. The number of inbound tourists to Ukraine sharply declined after 2013 because of the socio-political situation in the country. The analysis reveals significant changes in inbound and outbound tourism flow structures. The COVID-19 pandemic is shown to be a critical factor influencing the current state and prospects of the tourism industry