Physiologic Responsiveness to Social Interaction in Mothers with and without a History of Depression

Maternal depression is associated with child psychiatric illness, especially in adolescent girls. Depressed mothers have difficulty regulating their own emotions and display diminished emotional reactivity when interacting with their children. In order to better understand the role that such interpersonal difficulties may play in the intergenerational transmission of depression, the present study examined vagal responsiveness, a physiologic indictor of emotion regulation, via measurement of high-frequency heart rate variability (HF-HRV) in pairs of mothers and adolescent daughters during interaction tasks in which they discussed pleasant events and disagreements. Participants included 23 mother-daughter pairs in which both mother and daughter had a history of depression and 23 non-psychiatric control pairs in which neither mother nor daughter had a history of psychiatric illness. Separate piecewise linear growth models were used to compare slopes of HF-HRV between groups of mothers and daughters. Results showed that control mothers and daughters displayed positive slopes in HF-HRV during both pleasant events and disagreement discussions, and negative slopes during rest periods following the discussions. In contrast, mothers and daughters with a history of depression showed minimal vagal responsiveness during discussion and rest periods. These results suggest that while control mothers and daughters displayed vagal flexibility and activation during both discussion tasks—which may facilitate positive socio-emotional engagement and development—depressed individuals exhibited a lack of flexible and sensitive vagal responsiveness. Finally, exploratory analyses examined the covariation of vagal responsiveness between mother-daughter pairs. During the pleasant events discussion, a strong positive correlation was obtained among control dyads and no association was found for controls during the disagreement discussion. In contrast, during both discussions, a negative association between mothers’ and daughters’ patterns of responsiveness was obtained among dyads with a history of depression. The inverse correlations found in dyads with a history of depression suggest that in these individual dyads, mothers and daughters experienced the discussions in different ways, whereas the positive correlation found for control dyads suggests that control mothers and daughters experienced the pleasant events discussion similarly. Treatment strategies aimed at eliciting and sustaining mutual positive emotional interactions may be beneficial for depressed dyads

\u3cem\u3eIn vitro\u3c/em\u3e Digestibility and Methane Production of Two Tropical Grasses: Plant Spacing and Grazing Frequency

This study was carried out to investigate the influence of plant spacing and grazing frequency on the in vitro gas production, digestibility, and methane production of Guinea grass (Megathyrsus maximus) and Elephant grass (Cenchrus purpureus) in the humid southwest part of Nigeria. The experiment was laid in a 2 x 2 x 2 factorial arrangement in a split-split-plot design with three replicates, which consisted of two grazing frequency (3 and 6-week) as the main plot, two grass species: Guinea grass (M. maximus) and Elephant grass (C. purpureus) as the sub plot and two plant spacing (1m x 1m and 0.5m x 1m) as the sub-sub plot. A total area of 2496 m2 of an existing plot established April 2019 was used in conducting this experiment. In May 2020, the grasses were cut back at the commencement of this experiment to 15cm above ground surface and NPK 20:10:10 fertilizer was applied 8 days after cut back at the rate of 120 kg N/ha. The result showed a significant (Pin vitro gas production, digestibility (IVDMD) and methane gas production. The CP content of C. purpureus (18.14 %) grazed at 3-week GF with 1 m x 1 m spacing was significantly (PM. maximus grazed at 3-week at the narrower spacing with the IVDMD been the highest (64.53% DM) and the least gas volume was produced by C. purpureus grazed at 3-week with a narrower spacing, whereas the least digested was C. purpureus grazed at 6-week with narrower spacing. The methane production of C. purpureus grazed at 3-week with wider spacing was the least (5.53 ml/200mg DM) while the highest methane was produced by M. maximus also grazed at 3-week with 0.5m x 1m spacing though not statistically (P\u3e0.05) different from the methane of same species with same plant spacing at 6-week grazing frequency. It can be concluded that grazing at 3-week grazing frequency and narrower spacing will help reduce methane for C. purpureus and improve digestibility for M. maximus

Antihydrogen studies in ALPHA

he ALPHA experiment studies antihydrogen as a means to investigate the symmetry of matter and antimatter. Spectroscopic studies of the anti-atom hold the promise of the most precise direct comparisons of matter and antimatter possible. ALPHA was the first to trap antihydrogen in a magnetic trap, allowing the first ever detection of atomic transitions in an anti-atom. More recently, through stochastic heating, we have also been able to put a new limit on the charge neutrality of antihydrogen. ALPHA is currently preparing to perform the first laser-spectroscopy of antihydrogen, hoping to excite the 2s state using a two-photon transition from the 1s state. We discuss the recent results as well as the key developments that led to these successes and discuss how we are preparing to perform the first laser-spectroscopy. We will also discuss plans to use our novel technique for gravitational tests on antihydrogen for a direct measurement of the sign of the gravitational force on antihydrogen

Variational calculations for the hydrogen-antihydrogen system with a mass-scaled Born-Oppenheimer potential

The problem of proton-antiproton motion in the ${\rm H}$--${\rm \bar{H}}$ system is investigated by means of the variational method. We introduce a modified nuclear interaction through mass-scaling of the Born-Oppenheimer potential. This improved treatment of the interaction includes the nondivergent part of the otherwise divergent adiabatic correction and shows the correct threshold behavior. Using this potential we calculate the vibrational energy levels with angular momentum 0 and 1 and the corresponding nuclear wave functions, as well as the S-wave scattering length. We obtain a full set of all bound states together with a large number of discretized continuum states that might be utilized in variational four-body calculations. The results of our calculations gives an indication of resonance states in the hydrogen-antihydrogen system

Indirect detection of Dark Matter with the ANTARES Neutrino Telescope

[EN] One of the main objectives of the ANTARES neutrino telescope is the search for neutrinos produced in self-annihilation of Dark Matter (DM) particles. The analysis for different sources of DM (Sun, Galactic Center, Earth, ...) or DM models (SUSY, Secluded) will be described and the results presented. The specific advantages of neutrino telescopes in general and of ANTARES in particular will be explained. As an example, the indirect search for DM towards the Sun performed by neutrino telescopes currently leads to more stringent limits on the spin-dependent WIMP-nucleon cross section with respect to existing direct detection experiments.We acknowledge the financial support of the Spanish Ministerio de Economía y Competitividad, Grants FPA2012-37528-C02-02, and Consolider MultiDark CSD2009-00064, of the Generalitat Valenciana, Grants ACOMP/2015/175 PrometeoII/2014/079 and of the European FEDER funds.Ardid Ramírez, M. (2016). Indirect detection of Dark Matter with the ANTARES Neutrino Telescope. EPJ Web of Conferences. 116:1-5. https://doi.org/10.1051/epjconf/201611604002S1511

Antihydrogen and mirror-trapped antiproton discrimination: Discriminating between antihydrogen and mirror-trapped antiprotons in a minimum-B trap

Recently, antihydrogen atoms were trapped at CERN in a magnetic minimum (minimum-B) trap formed by superconducting octupole and mirror magnet coils. The trapped antiatoms were detected by rapidly turning off these magnets, thereby eliminating the magnetic minimum and releasing any antiatoms contained in the trap. Once released, these antiatoms quickly hit the trap wall, whereupon the positrons and antiprotons in the antiatoms annihilated. The antiproton annihilations produce easily detected signals; we used these signals to prove that we trapped antihydrogen. However, our technique could be confounded by mirror-trapped antiprotons, which would produce seemingly-identical annihilation signals upon hitting the trap wall. In this paper, we discuss possible sources of mirror-trapped antiprotons and show that antihydrogen and antiprotons can be readily distinguished, often with the aid of applied electric fields, by analyzing the annihilation locations and times. We further discuss the general properties of antiproton and antihydrogen trajectories in this magnetic geometry, and reconstruct the antihydrogen energy distribution from the measured annihilation time history.Comment: 17 figure

Dark matter search results from the complete exposure of the PICO-60 C3F8 bubble chamber

[EN] Final results are reported from operation of the PICO-60 C3F8 dark matter detector, a bubble chamber filled with 52 kg of C3F8 located in the SNOLAB underground laboratory. The chamber was operated at thermodynamic thresholds as low as 1.2 keV without loss of stability. A new blind 1404-kg-day exposure at 2.45 keV threshold was acquired with approximately the same expected total background rate as the previous 1167-kg-day exposure at 3.3 keV. This increased exposure is enabled in part by a new optical tracking analysis to better identify events near detector walls, permitting a larger fiducial volume. These results set the most stringent direct-detection constraint to date on the weakly interacting massive particle (WIMP)-proton spin-dependent cross section at 3.2 x 10(-41) cm(2) for a 25 GeV WIMP, improving on previous PICO results for 3-5 GeV WIMPs by an order of magnitude.The PICO Collaboration wishes to thank SNOLAB and its staff for support through underground space, logistical and technical services. SNOLAB operations are supported by the Canada Foundation for Innovation and the Province of Ontario Ministry of Research and Innovation, with underground access provided by Vale at the Creighton mine site. We are grateful to Genevieve Belanger and Alexander Pukhov of the Universit e de Savoie for their useful correspondence regarding the interpretation of PICO results. We wish to acknowledge the support of the Natural Sciences and Engineering Research Council of Canada (NSERC) and the Canada Foundation for Innovation (CFI) for funding. We acknowledge the support from the National Science Foundation (NSF) (Grants No. 0919526, No. 1506337, No. 1242637, No. 1205987, and No. 1806722). We acknowledge that this work is supported by the U.S. Department of Energy (DOE) Office of Science, Office of High Energy Physics (under Award No. DE-SC-0012161), by the DOE Office of Science Graduate Student Research (SCGSR) award, by DGAPA-UNAM (PAPIIT No. IA100118) and Consejo Nacional de Ciencia y Tecnologia (CONACyT, Mexico, Grants No. 252167 and No. A1-S-8960), by the Department of Atomic Energy (DAE), Government of India, under the Centre for AstroParticle Physics II project (CAPP-II) at the Saha Institute of Nuclear Physics (SINP), European Regional Development FundProject "Engineering applications of microworld physics" (No. CZ. 02.1.01/0.0/0.0/16_019/0000766), and the Spanish (Ministry of Science, Innovation and Universities) Ministerio de Ciencia, Innovacion y Universidades (Red Consolider MultiDark, FPA2017-90566-REDC). This work is partially supported by the Kavli Institute for Cosmological Physics at the University of Chicago through NSF Grant No. 1125897, and an endowment from the Kavli Foundation and its founder Fred Kavli. We also wish to acknowledge the support from Fermi National Accelerator Laboratory under Contract No. DE-AC02-07CH11359, and from Pacific Northwest National Laboratory, which is operated by Battelle for the U.S. Department of Energy under Contract No. DE-AC05-76RL01830. We also thank Compute Canada (www.computecanada.ca) and the Centre for Advanced Computing, ACENET, Calcul Quebec, Compute Ontario and WestGrid for computational support.Amole, C.; Ardid Ramírez, M.; Arnquist, I.; Asner, DM.; Baxter, D.; Behnke, E.; Bressler, M.... (2019). Dark matter search results from the complete exposure of the PICO-60 C3F8 bubble chamber. Physical Review D: covering particles, fields, gravitation, and cosmology. 100(2):1-9. https://doi.org/10.1103/PhysRevD.100.022001191002Olive, K. A. 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Physical Review Letters, 121(7). doi:10.1103/physrevlett.121.071801Cowan, G., Cranmer, K., Gross, E., & Vitells, O. (2011). Asymptotic formulae for likelihood-based tests of new physics. The European Physical Journal C, 71(2). doi:10.1140/epjc/s10052-011-1554-0Lewin, J. D., & Smith, P. F. (1996). Review of mathematics, numerical factors, and corrections for dark matter experiments based on elastic nuclear recoil. Astroparticle Physics, 6(1), 87-112. doi:10.1016/s0927-6505(96)00047-3Fitzpatrick, A. L., Haxton, W., Katz, E., Lubbers, N., & Xu, Y. (2013). The effective field theory of dark matter direct detection. Journal of Cosmology and Astroparticle Physics, 2013(02), 004-004. doi:10.1088/1475-7516/2013/02/004Anand, N., Fitzpatrick, A. L., & Haxton, W. C. (2014). Weakly interacting massive particle-nucleus elastic scattering response. Physical Review C, 89(6). doi:10.1103/physrevc.89.065501Gresham, M. I., & Zurek, K. M. (2014). Effect of nuclear response functions in dark matter direct detection. Physical Review D, 89(12). doi:10.1103/physrevd.89.123521Gluscevic, V., Gresham, M. I., McDermott, S. D., Peter, A. H. G., & Zurek, K. M. (2015). Identifying the theory of dark matter with direct detection. Journal of Cosmology and Astroparticle Physics, 2015(12), 057-057. doi:10.1088/1475-7516/2015/12/057Amole, C., Ardid, M., Arnquist, I. J., Asner, D. M., Baxter, D., Behnke, E., … Brice, S. J. (2016). Improved dark matter search results from PICO-2L Run 2. Physical Review D, 93(6). doi:10.1103/physrevd.93.061101Behnke, E., Besnier, M., Bhattacharjee, P., Dai, X., Das, M., Davour, A., … Zacek, V. (2017). Final results of the PICASSO dark matter search experiment. Astroparticle Physics, 90, 85-92. doi:10.1016/j.astropartphys.2017.02.005Felizardo, M., Girard, T. A., Morlat, T., Fernandes, A. C., Ramos, A. R., Marques, J. G., … Marques, R. (2014). The SIMPLE Phase II dark matter search. Physical Review D, 89(7). doi:10.1103/physrevd.89.072013Aprile, E., Aalbers, J., Agostini, F., Alfonsi, M., Althueser, L., Amaro, F. D., … Baudis, L. (2019). Constraining the Spin-Dependent WIMP-Nucleon Cross Sections with XENON1T. Physical Review Letters, 122(14). doi:10.1103/physrevlett.122.141301Fu, C., Cui, X., Zhou, X., Chen, X., Chen, Y., … Fang, D. (2017). Spin-Dependent Weakly-Interacting-Massive-Particle–Nucleon Cross Section Limits from First Data of PandaX-II Experiment. Physical Review Letters, 118(7). doi:10.1103/physrevlett.118.071301Aartsen, M. G., Ackermann, M., Adams, J., Aguilar, J. A., Ahlers, M., Ahrens, M., … Ansseau, I. (2017). Search for annihilating dark matter in the Sun with 3 years of IceCube data. The European Physical Journal C, 77(3). doi:10.1140/epjc/s10052-017-4689-9Tanaka, T., Abe, K., Hayato, Y., Iida, T., Kameda, J., Koshio, Y., … Nakahata, M. (2011). AN INDIRECT SEARCH FOR WEAKLY INTERACTING MASSIVE PARTICLES IN THE SUN USING 3109.6 DAYS OF UPWARD-GOING MUONS IN SUPER-KAMIOKANDE. The Astrophysical Journal, 742(2), 78. doi:10.1088/0004-637x/742/2/78Choi, K., Abe, K., Haga, Y., Hayato, Y., Iyogi, K., Kameda, J., … Nakahata, M. (2015). Search for Neutrinos from Annihilation of Captured Low-Mass Dark Matter Particles in the Sun by Super-Kamiokande. Physical Review Letters, 114(14). doi:10.1103/physrevlett.114.141301Akerib, D. S., Araújo, H. M., Bai, X., Bailey, A. J., Balajthy, J., Beltrame, P., … Boulton, E. M. (2016). Results on the Spin-Dependent Scattering of Weakly Interacting Massive Particles on Nucleons from the Run 3 Data of the LUX Experiment. Physical Review Letters, 116(16). doi:10.1103/physrevlett.116.161302Adrián-Martínez, S., Albert, A., André, M., Anton, G., Ardid, M., Aubert, J.-J., … Basa, S. (2016). Limits on dark matter annihilation in the sun using the ANTARES neutrino telescope. Physics Letters B, 759, 69-74. doi:10.1016/j.physletb.2016.05.019Adrián-Martínez, S., Albert, A., André, M., Anton, G., Ardid, M., Aubert, J.-J., … Basa, S. (2016). A search for Secluded Dark Matter in the Sun with the ANTARES neutrino telescope. Journal of Cosmology and Astroparticle Physics, 2016(05), 016-016. doi:10.1088/1475-7516/2016/05/016Agnes, P., Albuquerque, I. F. M., Alexander, T., Alton, A. K., Araujo, G. R., Asner, D. M., … Batignani, G. (2018). Low-Mass Dark Matter Search with the DarkSide-50 Experiment. Physical Review Letters, 121(8). doi:10.1103/physrevlett.121.081307Aprile, E., Aalbers, J., Agostini, F., Alfonsi, M., Althueser, L., Amaro, F. D., … Bauermeister, B. (2018). Dark Matter Search Results from a One Ton-Year Exposure of XENON1T. Physical Review Letters, 121(11). doi:10.1103/physrevlett.121.111302Akerib, D. S., Alsum, S., Araújo, H. M., Bai, X., Bailey, A. J., Balajthy, J., … Biesiadzinski, T. P. (2017). 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Aspects of 1S-2S spectroscopy of trapped antihydrogen atoms

Antihydrogen atoms are now routinely trapped in small numbers. One of the purposes of this effort is to make precision comparisons of the 1S-2S transition in hydrogen and antihydrogen as a precision test of the CPT theorem. We investigate, through calculations and simulations, various methods by which the 1S-2S transition may be probed with only a few trapped atoms. We consider the known constraints from typical experimental geometries, detection methods, sample temperatures, laser light sources etc and we identify a viable path towards a measurement of this transition at the $10^{−1}$1 level in a realistic scenario. We also identify ways in which such a first measurement could be improved upon as a function of projected changes and improvements in antihydrogen synthesis and trapping. These calculations recently guided the first observation of the 1S-2S transition in trapped antihydrogen

Physics with antihydrogen

Performing measurements of the properties of antihydrogen, the bound state of an antiproton and a positron, and comparing the results with those for ordinary hydrogen, has long been seen as a route to test some of the fundamental principles of physics. There has been much experimental progress in this direction in recent years, and antihydrogen is now routinely created and trapped and a range of exciting measurements probing the foundations of modern physics are planned or underway. In this contribution we review the techniques developed to facilitate the capture and manipulation of positrons and antiprotons, along with procedures to bring them together to create antihydrogen. Once formed, the antihydrogen has been detected by its destruction via annihilation or field ionization, and aspects of the methodologies involved are summarized. Magnetic minimum neutral atom traps have been employed to allow some of the antihydrogen created to be held for considerable periods. We describe such devices, and their implementation, along with the cusp magnetic trap used to produce the first evidence for a low-energy beam of antihydrogen. The experiments performed to date on antihydrogen are discussed, including the first observation of a resonant quantum transition and the analyses that have yielded a limit on the electrical neutrality of the anti-atom and placed crude bounds on its gravitational behaviour. Our review concludes with an outlook, including the new ELENA extension to the antiproton decelerator facility at CERN, together with summaries of how we envisage the major threads of antihydrogen physics will progress in the coming years