Adsorption isotherms of H2_{2} and mixtures of H2_{2}, CH4_{4}, CO and CO2_{2} on copper plated stainless steel at 4.2 K

Adsorption isotherms in the pressure range 10$^{-11}$ to 10$^{-6} Torr have been measured for H$_2$and mixtures of H$_2$and CH$_4$, CO and CO$_2$on copper plated stainless steel at 4.2 K. The measurements have been focused on the behaviour of the isotherms at low surface coverage, up to a few monolayers of adsorbed gas on the cold surface. The isotherms were measured in a static situation with a small amount of gas injected for each point on the isotherm. Co-adsorption measurements of H$_2$with CH$_4$, CO and CO$_2$as well as adsorption of H$_2$on condensates of CH$_4$, CO and CO$_2$have been made. A cryotrapping effect of H$_2$is seen when co-adsorbing the gas mixtures, especially strong for the mixture of H$_2$and CO$_2$. The measurements show that CO$_2$condensed at 4.2 K may have a porous structure that H$_2$can penetrate, while CO and CH$_4$have rather dense structures when adsorbed at 4.2K. The measurements have been done within the framework of the Large Hadron Collider (LHC) project at CERN, Geneva, Switzerland, where superconducting magnets will be used to produce a magnetic field of about 9 T around the arcs of the 27 km long quasi-circular accelerator. Synchrotron radiation produced by the circulating proton beam in the superconducting magnets will induce desorption of neutral gas molecules, mainly H$_2$, CH$_4$, CO and CO$_2$, from the inner surface of the vacuum chamber. The desorbed gas molecules will be physisorbed on the cold surfaces in the vacuum chamber and they may induce vacuum instabilities in the accelerator. Hence it is of importance to have knowledge of the mixed adsorption isotherms of these gases at low temperatures

Status of COLDDIAG: A Cold Vacuum Chamber for Diagnostics

One of the still open issues for the development of superconducting insertion devices is the understanding of the beam heat load. With the aim of measuring the beam heat load to a cold bore and the hope to gain a deeper understanding in the beam heat load mechanisms, a cold vacuum chamber for diagnostics is under construction. The following diagnostics will be implemented: i) retarding field analyzers to measure the electron energy and flux, ii) temperature sensors to measure the total heat load, iii) pressure gauges, iv) and mass spectrometers to measure the gas content. The inner vacuum chamber will be removable in order to test different geometries and materials. This will allow the installation of the cryostat in different synchrotron light sources. COLDDIAG will be built to fit in a short straight section at ANKA. A first installation at the synchrotron light source Diamond is foreseen in June 2011. Here we describe the technical design report of this device and the planned measurements with beam.Comment: Presented at First International Particle Accelerator Conference, IPAC'10, Kyoto, Japan, from 23 to 28 May 201

Chromatin modifier developmental pluripotency associated factor 4 (DPPA4) is a candidate gene for alcohol-induced developmental disorders

Peer reviewe

Digital inclusion and participation of people with intellectual disabilities during COVID-19: A rapid review and international bricolage

The COVID-19 pandemic has meant a rapid transfer of everyday activities to the online world. Information and communication technologies (ICTs) have become more embedded than ever in people's lives. This investigation addresses how this change has affected the lives of people with intellectual disabilities (ID). A two-step design was used. A rapid review was conducted on empirical studies published between January 2019 and June 2021. Search terms related to ID, ICT use and COVID-19. A qualitative international bricolage was also conducted corresponding to author nationalities. Data gathered from the review and bricolage were analysed separately using thematic analysis and relationally synthesised. Digital solutions to provide access to COVID-19 information and guidance seemed inadequate but were seldom empirically studied. Digital poverty, literacy and exclusion remain significant issues for people with ID internationally. People and their carers experienced reduced and removed service provision, loneliness and impoverished daily lives during the pandemic; amelioration of which was facilitated by digital solutions. One solution often used was videoconferencing. Prior experience of digital participation, adequate finances, connection, support and digital literacy mentoring for both people with ID and those providing services and support facilitated digital inclusion. Digital exclusion during COVID-19 was exacerbated by sociopolitical, structural, individual and support-related barriers. Although awareness of digital exclusion appears to have been raised, the extent to which this has led to action and change remains unclear. Despite digital exclusion and digital participation benefitting continuation of life, social and emotional well-being and autonomy, COVID-19 has not provided the impetus to eradicate digital poverty for people with ID. Governmental support, digital education, creativity and problem solving are required to enable people with ID the human right to be included in the digital world at this essential time and into the future

Digital inclusion and participation of people with intellectual disabilities during COVID‐19: A rapid review and international bricolage

The COVID-19 pandemic has meant a rapid transfer of everyday activities to the online world. Information and communication technologies (ICTs) have become more embedded than ever in people’s lives. This investigation addresses how this change has affected the lives of people with intellectual disabilities (ID). A two-step design was used. A rapid review was conducted on empirical studies published between January 2019 and June 2021. Search terms related to ID, ICT use and COVID-19. A qualitative international bricolage was also conducted corresponding to author nationalities. Data gathered from the review and bricolage were analysed separately using thematic analysis and relationally synthesised. Digital solutions to provide access to COVID-19 information and guidance seemed inadequate but were seldom empirically studied. Digital poverty, literacy and exclusion remain significant issues for people with ID internationally. People and their carers experienced reduced and removed service provision, loneliness and impoverished daily lives during the pandemic; amelioration of which was facilitated by digital solutions. One solution often used was videoconferencing. Prior experience of digital participation, adequate finances, connection, support and digital literacy mentoring for both people with ID and those providing services and support facilitated digital inclusion. Digital exclusion during COVID-19 was exacerbated by sociopolitical, structural, individual and support-related barriers. Although awareness of digital exclusion appears to have been raised, the extent to which this has led to action and change remains unclear. Despite digital exclusion and digital participation benefitting continuation of life, social and emotional well-being and autonomy, COVID-19 has not provided the impetus to eradicate digital poverty for people with ID. Governmental support, digital education, creativity and problem solving are required to enable people with ID the human right to be included in the digital world at this essential time and into the future

The LHC test string: first operational experience

CERN operates the first version of the LHC Test String which consists of one quadrupole and three 10-m twin aperture dipole magnets. An experimental programme aiming at the validation of the LHC systems started in February 1995. During this programme the string has been powered 100 times 35 of which at 12.4 kA or above. The experiments have yielded a number of results some of which, like quench recovery for cryogenics, have modified the design of subsystems of LHC. Others, like controlled helium leaks in the cold bore and quench propagation bewteen magnets, have given a better understanding on the evolution of the phenomena inside a string of superconducting magnets cooled at superfluid helium temperatures. Following the experimental programme, the string will be powered up and powered down in one hour cycles as a fatigue test of the structure thus simulating 20 years of operation of LHC

The transmission problem on a three-dimensional wedge

We consider the transmission problem for the Laplace equation on an infinite three-dimensional wedge, determining the complex parameters for which the problem is well-posed, and characterizing the infinite multiplicity nature of the spectrum. This is carried out in two formulations leading to rather different spectral pictures. One formulation is in terms of square integrable boundary data, the other is in terms of finite energy solutions. We use the layer potential method, which requires the harmonic analysis of a non-commutative non-unimodular group associated with the wedge