Hydrodynamic theory for granular gases

A granular gas subjected to a permanent injection of energy is described by means of hydrodynamic equations derived from a moment expansion method. The method uses as reference function not a Maxwellian distribution $f_{\sf M}$ but a distribution $f_0 = \Phi f_{\sf M}$, such that $\Phi$ adds a fourth cumulant $\kappa$ to the velocity distribution. The formalism is applied to a stationary conductive case showing that the theory fits extraordinarily well the results coming from our molecular dynamic simulations once we determine $\kappa$ as a function of the inelasticity of the particle-particle collisions. The shape of $\kappa$ is independent of the size $N$ of the system.Comment: 10 pages, 9 figures, more about our research in http://www.cec.uchile.cl/cinetica

Analysis of Ductile Bursting in Pressure Vessels of Texture-Hardening and Filament-Wrapped Materials

Analyses are presented for predicting the strength governed by the plastic tensile instability (PTI) phenomenon in thin-walled cylindrical and spherical pressure vessels constructed of texture- hardening alloys and with or without over-wrapped filaments. These analyses are important in predicting ductile bursting of pressure vessels used in such high-performance applications as high-pressure storage bottles, liquid-propellant tankage, and solid rocket casings. The analyses cover cylindrical pressure vessels subject to any ratio of biaxial stresses. Also means of estimating the effect of finite length is presented. Spherical vessels of texture- hardening material and cylindrical vessels with filaments over wrapped on a texture-hardening metallic substrate are treated as special cases. The analytical results are compared with available experimental results with good success.Yeshttps://us.sagepub.com/en-us/nam/manuscript-submission-guideline

Post COVID-19 implications on genetic diversity and genomics research & innovation: A call for governance and research capacity. White paper.

This is the final version. Available from the Food and Agriculture Organisation via the DOI in this record. At a time of significant technological change and digitization in the biological sciences, the COVID19 pandemic has highlighted again the inequities in the research and innovation ecosystem. Based on a consultation with an internationally diverse group of stakeholders from multiple fields and professions, and on a broadly representative set of case studies, this report offers a new approach to the global governance of genetic diversity and genomic research and innovation. We recommend that in addition to the many valuable efforts at the macro-policy level and at the micro-level of projects, teams and organizations, the global community concerned with genetic diversity and genomic research and innovation should devise and implement a meso-level initiative that includes three main components: 1. First, it should establish a new professional capacity to govern research and innovation at the meso-level. Governance capacity, built through a networked community of practice, has the benefit of connecting and integrating macrolevel policy intentions with micro-level actions. It facilitates a consistent professional basis from which local and regional level flexibilities can generate new norms of reflection that better integrate multiple synergies, reconcile tensions, recognize inequities, and redress persistent inequalities. 2. Second, the global community should redouble efforts to build research capacity in genomic research and innovation in the Global South and for Indigenous Peoples. Such an effort should be focused on broader programmatic objectives that facilitate cross-national and cross-regional collaboration, as well as enhancing research communities in the Global South and in Indigenous communities. Together, the twin capacities of governance and research can reduce power differentials among diverse actors and support crisisbased imperatives for data openness. 3. Third, we recommend that existing global policy frameworks interface with research governance and capacity investment. This meso-level approach should gain the commitment and support from national and international policy bodies, embedded within existing specific issue-areas (health, agriculture, environment). A new approach, one that can better respond to global crises though more open, inclusive and equitable participation in research and innovation, is necessary to resolve the tensions among openness, innovation and equity that the current discourse on genetic diversity reiterates. Failure to systematically address the social and technical governance challenges will result in further fragmentation, inequity and vulnerability for decades to come. Conversely, investing in the current historical moment of the pandemic to build twin capacities for meso-level governance and research is poised to prevent and/or reduce the impact of future ecological crises, while contributing to planetary sustainability and prosperity in the 21st century for current and future generations.European CommissionAlan Turing Institut

Analysis of LIGO data for gravitational waves from binary neutron stars

We report on a search for gravitational waves from coalescing compact binary systems in the Milky Way and the Magellanic Clouds. The analysis uses data taken by two of the three LIGO interferometers during the first LIGO science run and illustrates a method of setting upper limits on inspiral event rates using interferometer data. The analysis pipeline is described with particular attention to data selection and coincidence between the two interferometers. We establish an observational upper limit of $\mathcal{R}<$1.7 \times 10^{2}$per year per Milky Way Equivalent Galaxy (MWEG), with 90coalescence rate of binary systems in which each component has a mass in the range 1--3$M_\odot$.Comment: 17 pages, 9 figure

Search for composite and exotic fermions at LEP 2

A search for unstable heavy fermions with the DELPHI detector at LEP is reported. Sequential and non-canonical leptons, as well as excited leptons and quarks, are considered. The data analysed correspond to an integrated luminosity of about 48 pb^{-1} at an e^+e^- centre-of-mass energy of 183 GeV and about 20 pb^{-1} equally shared between the centre-of-mass energies of 172 GeV and 161 GeV. The search for pair-produced new leptons establishes 95% confidence level mass limits in the region between 70 GeV/c^2 and 90 GeV/c^2, depending on the channel. The search for singly produced excited leptons and quarks establishes upper limits on the ratio of the coupling of the excited fermio

Search for lightest neutralino and stau pair production in light gravitino scenarios with stau NLSP

Promptly decaying lightest neutralinos and long-lived staus are searched for in the context of light gravitino scenarios. It is assumed that the stau is the next to lightest supersymmetric particle (NLSP) and that the lightest neutralino is the next to NLSP (NNLSP). Data collected with the Delphi detector at centre-of-mass energies from 161 to 183 \GeV are analysed. No evidence of the production of these particles is found. Hence, lower mass limits for both kinds of particles are set at 95% C.L.. The mass of gaugino-like neutralinos is found to be greater than 71.5 GeV/c^2. In the search for long-lived stau, masses less than 70.0 to 77.5 \GeVcc are excluded for gravitino masses from 10 to 150 \eVcc . Combining this search with the searches for stable heavy leptons and Minimal Supersymmetric Standard Model staus a lower limit of 68.5 \GeVcc may be set for the stau mas

Study of Tau-pair Production in Photon-Photon Collisions at LEP and Limits on the Anomalous Electromagnetic Moments of the Tau Lepton

Tau-pair production in the process e+e- -> e+e-tau+tau- was studied using data collected by the DELPHI experiment at LEP2 during the years 1997 - 2000. The corresponding integrated luminosity is 650 pb^{-1}. The values of the cross-section obtained are found to be in agreement with QED predictions. Limits on the anomalous magnetic and electric dipole moments of the tau lepton are deduced.Comment: 20 pages, 9 figures, Accepted by Eur. Phys. J.