Discussion on Electric Power Supply Systems for All Electric Aircraft

The electric power supply system is one of the most important research areas within sustainable and energy-efcient aviation for more- and especially all electric aircraft. This paper discusses the history in electrication, current trends with a broad overview of research activities, state of the art of electrication and an initial proposal for a short-range aircraft. It gives an overviewof the mission prole, electrical sources, approaches for the electrical distribution system and the required electrical loads. Current research aspects and questions are discussed, including voltage levels, semiconductor technology, topologies and reliability. Because of the importance for safety possible circuit breakers for the proposed concept are also presented and compared, leading to a initial proposal. Additionally, a very broad review of literature and a state of the art discussion of the wiring harness is given, showing that this topic comes with a high number of aspects and requirements. Finally, the conclusion sums up the most important results and gives an outlook on important future research topics

Mental health supportive services during COVID-19: Proposing an online, self-guided Acceptance and Commitment Therapy program for parents in the disability community

Parents of Children with Intellectual and Developmental Disabilities (I/DD) often experience stress, and the COVID-19 pandemic has likely increased their stress. In the current paper, we describe four things. First, we describe how mental telehealth treatments can effectively decrease parent stress, including programs that target behavior training and those that provide therapy. Teleheath programs are delivered by phone, computer, or fully online. Second, we describe challenges of these programs and explain how online, self-guided programs may help address these challenges. Third, we explain our online, self-guided program based in Acceptance and Commitment Therapy (ACT). ACT is a specific type of therapy that helps people notice their moods and their thoughts to help manage stress. Finally, we conclude by proposing a call for collaboration to improve and expand our online, self-guided, ACT program

Self-organised reactivation maintains and reinforces memories despite synaptic turnover

Long-term memories are believed to be stored in the synapses of cortical neuronal networks. However, recent experiments report continuous creation and removal of cortical synapses, which raises the question how memories can survive on such a variable substrate. Here, we study the formation and retention of associative memory in a computational model based on Hebbian cell assemblies in the presence of both synaptic and structural plasticity. During rest periods, such as may occur during sleep, the assemblies reactivate spontaneously, reinforcing memories against ongoing synapse removal and replacement. Brief daily reactivations during rest-periods suffice to not only maintain the assemblies, but even strengthen them, and improve pattern completion, consistent with offline memory gains observed experimentally. While the connectivity inside memory representations is strengthened during rest phases, connections in the rest of the network decay and vanish thus reconciling apparently conflicting hypotheses of the influence of sleep on cortical connectivity

Diagnostic challenges in a child with early onset desmoplastic medulloblastoma and homozygous variants in MSH2 and MSH6

International audienceConstitutional mismatch repair deficiency (CMMRD) is an autosomal recessively inherited childhood cancer susceptibility syndrome caused by biallelic germline mutations in one of the mismatch repair (MMR

From LiNiO₂ to Li₂NiO₃ : Synthesis, Structures and Electrochemical Mechanisms in Li-Rich Nickel Oxides

The Li−Ni−O phase diagram contains a variety of compounds, most of which are electrochemically active in Li-ion batteries. Other than the well-known LiNiO2, here we report a facile solid-state method to prepare Li2NiO3 and other Li-rich Ni oxides of composition Li1+xNi1−xO2 (0 ≤ x ≤ 0.33). We characterize their crystal and electronic structure, exhibiting a highly oxidized Ni state and defects of various nature (Li−Ni disorder, stacking faults, oxygen vacancies). We then investigate the use of Li2NiO3 as a cathode active material and show its remarkably high specific capacity, which however fades quickly. While we demonstrate that the initial capacity is due to irreversible O2 release, such process stops quickly in favor of more classical reversible redox mechanisms that allow cycling the material for >100 cycles. After the severe oxygen loss (∼15−20%) and prolonged cycling, the Bragg reflections of Li2NiO3 disappear. Analysis of the diffracted intensities suggests the resulting phase is a disordered rock salt-type material with high Li content, close to Li0.5Ni0.5O, never reported to date and capable of Li diffusion. Our findings demonstrate that the Li−Ni−O phase diagram has not been fully investigated yet, especially concerning the preparation of new promising materials by out-of-equilibrium methods

Nerve Injury Evoked Loss of Latexin Expression in Spinal Cord Neurons Contributes to the Development of Neuropathic Pain

Nerve injury leads to sensitization mechanisms in the peripheral and central nervous system which involve transcriptional and post-transcriptional modifications in sensory nerves. To assess protein regulations in the spinal cord after injury of the sciatic nerve in the Spared Nerve Injury model (SNI) we performed a proteomic analysis using 2D-difference gel electrophoresis (DIGE) technology. Among approximately 2300 protein spots separated on each gel we detected 55 significantly regulated proteins after SNI whereof 41 were successfully identified by MALDI-TOF MS. Out of the proteins which were regulated in the DIGE analyses after SNI we focused on the carboxypeptidase A inhibitor latexin because protease dysfunctions contribute to the development of neuropathic pain. Latexin protein expression was reduced after SNI which could be confirmed by Western Blot analysis, quantitative RT-PCR and in-situ hybridisation. The decrease of latexin was associated with an increase of the activity of carboxypeptidase A indicating that the balance between latexin and carboxypeptidase A was impaired in the spinal cord after peripheral nerve injury due to a loss of latexin expression in spinal cord neurons. This may contribute to the development of cold allodynia because normalization of neuronal latexin expression in the spinal cord by AAV-mediated latexin transduction or administration of a small molecule carboxypeptidase A inhibitor significantly reduced acetone-evoked nociceptive behavior after SNI. Our results show the usefulness of proteomics as a screening tool to identify novel mechanisms of nerve injury evoked hypernociception and suggest that carboxypeptidase A inhibition might be useful to reduce cold allodynia

A compact and versatile dynamic flow cryostat for photon science

We have developed a helium gas flow cryostat for use on synchrotron tender to hard X-ray beamlines. Very efficient sample cooling is achieved because the sample is placed directly in the cooling helium flow on a removable sample holder. The cryostat is compact and easy to operate; samples can be changed in less than 5 min at any temperature. The cryostat has a temperature range of 2.5-325 K with temperature stability better than 0.1 K. The very wide optical angle and the ability to operate in any orientation mean that the cryostat can easily be adapted for different X-ray techniques. It is already in use on different beamlines at the European Synchrotron Radiation Facility (ESRF), ALBA Synchrotron Light Facility (ALBA), and Diamond Light Source (DLS) for inelastic X-ray scattering, powder diffraction, and X-ray absorption spectroscopy. Results obtained at these beamlines are presented here

Measurement of the cosmic ray spectrum above 4×10184{\times}10^{18} eV using inclined events detected with the Pierre Auger Observatory

A measurement of the cosmic-ray spectrum for energies exceeding $4{\times}10^{18}$ eV is presented, which is based on the analysis of showers with zenith angles greater than $60^{\circ}$ detected with the Pierre Auger Observatory between 1 January 2004 and 31 December 2013. The measured spectrum confirms a flux suppression at the highest energies. Above $5.3{\times}10^{18}$ eV, the "ankle", the flux can be described by a power law $E^{-\gamma}$ with index $\gamma=2.70 \pm 0.02 \,\text{(stat)} \pm 0.1\,\text{(sys)}$ followed by a smooth suppression region. For the energy ($E_\text{s}$) at which the spectral flux has fallen to one-half of its extrapolated value in the absence of suppression, we find $E_\text{s}=(5.12\pm0.25\,\text{(stat)}^{+1.0}_{-1.2}\,\text{(sys)}){\times}10^{19}$ eV.Comment: Replaced with published version. Added journal reference and DO

Energy Estimation of Cosmic Rays with the Engineering Radio Array of the Pierre Auger Observatory

The Auger Engineering Radio Array (AERA) is part of the Pierre Auger Observatory and is used to detect the radio emission of cosmic-ray air showers. These observations are compared to the data of the surface detector stations of the Observatory, which provide well-calibrated information on the cosmic-ray energies and arrival directions. The response of the radio stations in the 30 to 80 MHz regime has been thoroughly calibrated to enable the reconstruction of the incoming electric field. For the latter, the energy deposit per area is determined from the radio pulses at each observer position and is interpolated using a two-dimensional function that takes into account signal asymmetries due to interference between the geomagnetic and charge-excess emission components. The spatial integral over the signal distribution gives a direct measurement of the energy transferred from the primary cosmic ray into radio emission in the AERA frequency range. We measure 15.8 MeV of radiation energy for a 1 EeV air shower arriving perpendicularly to the geomagnetic field. This radiation energy -- corrected for geometrical effects -- is used as a cosmic-ray energy estimator. Performing an absolute energy calibration against the surface-detector information, we observe that this radio-energy estimator scales quadratically with the cosmic-ray energy as expected for coherent emission. We find an energy resolution of the radio reconstruction of 22% for the data set and 17% for a high-quality subset containing only events with at least five radio stations with signal.Comment: Replaced with published version. Added journal reference and DO