Assessing the Unitary RNN as an End-to-End Compositional Model of Syntax

We show that both an LSTM and a unitary-evolution recurrent neural network (URN) can achieve encouraging accuracy on two types of syntactic patterns: context-free long distance agreement, and mildly context-sensitive cross serial dependencies. This work extends recent experiments on deeply nested context-free long distance dependencies, with similar results. URNs differ from LSTMs in that they avoid non-linear activation functions, and they apply matrix multiplication to word embeddings encoded as unitary matrices. This permits them to retain all information in the processing of an input string over arbitrary distances. It also causes them to satisfy strict compositionality. URNs constitute a significant advance in the search for explainable models in deep learning applied to NLP

Layered direct policy search for learning hierarchical skills

Solutions to real world robotic tasks often require complex behaviors in high dimensional continuous state and action spaces. Reinforcement Learning (RL) is aimed at learning such behaviors but often fails for lack of scalability. To address this issue, Hierarchical RL (HRL) algorithms leverage hierarchical policies to exploit the structure of a task. However, many HRL algorithms rely on task specific knowledge such as a set of predefined sub-policies or sub-goals. In this paper we propose a new HRL algorithm based on information theoretic principles to autonomously uncover a diverse set of sub-policies and their activation policies. Moreover, the learning process mirrors the policys structure and is thus also hierarchical, consisting of a set of independent optimization problems. The hierarchical structure of the learning process allows us to control the learning rate of the sub-policies and the gating individually and add specific information theoretic constraints to each layer to ensure the diversification of the subpolicies. We evaluate our algorithm on two high dimensional continuous tasks and experimentally demonstrate its ability to autonomously discover a rich set of sub-policies

Wfs1 Is Expressed In Dopaminoceptive Regions Of The Amniote Brain And Modulates Levels Of D1-Like Receptors

During amniote evolution, the construction of the forebrain has diverged across different lineages, and accompanying the structural changes, functional diversification of the homologous brain regions has occurred. This can be assessed by studying the expression patterns of marker genes that are relevant in particular functional circuits. In all vertebrates, the dopaminergic system is responsible for the behavioral responses to environmental stimuli. Here we show that the brain regions that receive dopaminergic input through dopamine receptor D1 are relatively conserved, but with some important variations between three evolutionarily distant vertebrate lines–house mouse (Mus musculus), domestic chick (Gallus gallus domesticus) / common quail (Coturnix coturnix) and red-eared slider turtle (Trachemys scripta). Moreover, we find that in almost all instances, those brain regions expressing D1-like dopamine receptor genes also express Wfs1. Wfs1 has been studied primarily in the pancreas, where it regulates the endoplasmic reticulum (ER) stress response, cellular Ca2+ homeostasis, and insulin production and secretion. Using radioligand binding assays in wild type and Wfs1-/- mouse brains, we show that the number of binding sites of D1-like dopamine receptors is increased in the hippocampus of the mutant mice. We propose that the functional link between Wfs1 and D1-like dopamine receptors is evolutionarily conserved and plays an important role in adjusting behavioral reactions to environmental stimuli

Technical Guidelines for the Safe Movement of Cacao Germplasm. Revised from the FAO/IPGRI Technical Guidelines No. 20 (Fourth Update 2021)

The CacaoNet Technical Guidelines for the Safe Movement of Cacao Germplasm provide updated information on the precautions and quarantine measures that can be taken to minimise the risk of spread of pests and diseases when cacao genetic resources are being moved for research, crop improvement, plant breeding, exploration or conservation. These Guidelines are based on those last published by FAO/IPGRI in 1999 but have been revised and expanded by a group of experts set up within CacaoNet (the Global Cacao Genetic Resources Network coordinated by Bioversity International), to take account of new knowledge of the pests and diseases, including their current distribution, and advances in detection techniques. These CacaoNet Guidelines were first published on-line in 2012 but have been revised in 2014, in 2017 and now in 2021 to take account of new information received. The document includes general advice regarding safe procedures to use when moving cacao germplasm, whether as seed, vegetative and tissue cultured materials, and summarised information on the geographical spread and risks posed by significant pests and diseases of cacao. In addition, experts have contributed sections giving detailed information on the following: Virus diseases (Cacao necrosis virus, Cacao swollen shoot virus (CSSV), Cacao Yellow mosaic virus), Fungal diseases (Witches’ broom disease, Moniliophthora pod rot, Phytophthora pod rot, Vascular streak die-back, Verticillium wilt, Ceratocystis wilt, Rosellinia root rot), Insect pests (Cocoa pod borer, mirids/capsids, mosquito bug, other insect pests) and nematodes. Each section contains information on physical symptoms, geographical distribution, biology of the pest or disease and recommended quarantine measures. The publication of these Guidelines has been supported by financial and in-kind contributions from Bioversity International, the CGIAR Research Programme on Forests, Trees and Agroforestry, the Cocoa Research Association Ltd., UK (CRA Ltd., a UK-based organization managing scientific cocoa research on behalf of Mars Mondelēz International and the London Cocoa Trade NYSE-Liffe) and the University of Reading. CacaoNet has received additional financial support from Mars, the U.S. Department of Agriculture, Agricultural Research Service (USDA/ARS) and the World Cocoa Foundation (WCF)

The role of the international cocoa germplasm database and the international cocoa quarantine centre in information management and distribution of cocoa genetic resources

A range of physiological parameters (canopy light transmission, canopy shape, leaf size, flowering and flushing intensity) were measured from the International Clone Trial, typically over the course of two years. Data were collected from six locations, these being: Brazil, Ecuador, Trinidad, Venezuela, Côte d’Ivoire and Ghana. Canopy shape varied significantly between clones, although it showed little variation between locations. Genotypic variation in leaf size was differentially affected by the growth location; such differences appeared to underlie a genotype by environment interaction in relation to canopy light transmission. Flushing data were recorded at monthly intervals over the course of a year. Within each location, a significant interaction was observed between genotype and time of year, suggesting that some genotypes respond to a greater extent than others to environmental stimuli. A similar interaction was observed for flowering data, where significant correlations were found between flowering intensity and temperature in Brazil and flowering intensity and rainfall in Côte d’Ivoire. The results demonstrate the need for local evaluation of cocoa clones and also suggest that the management practices for particular planting material may need to be fine-tuned to the location in which they are cultivated

ATscale – Establishing a Cross-Sector Partnership to Increase Access to Assistive Technology

Given existing gaps in access to Assistive Technology (AT) globally, it is important to think broadly and identify innovative approaches to overcome them. After an initial scoping in 2018, involving consultations and landscape analyses, ATscale, the Global Partnership for Assistive Technology was launched at the Global Disability Summit in July 2018 with the aim of reaching 500 million more people with life-changing AT by 2030. Applying lessons-learned from other areas of global health and development, ATscale was established with the recognition that to influence the complex systems for AT access, a broad set of stakeholders is needed to invest in and coordinate a multifaceted, systematic approach spanning market shaping, capacity development, and political prioritisation. Already, ATscale has demonstrated how a multi-sector group can come together and develop a cohesive strategy. This strategy overview has been released and shared broadly for additional consultation and feedback to further refine ATscale’s approach moving forward. ATscale has captured the attention of a diverse set of stakeholders. It now has eleven organisations within the Forming Committee and a broad community willing to inform its development. Now that it has been established, ATscale is working to move from an initial forming phase to a more formal organisation and to refine its operating model by late 2019 or early 2020. While there is significant momentum towards taking new, innovative approaches to address the gaps in access to quality, affordable AT for all, research shows that a wide range of systemic, underlying barriers and cross-cutting factors are contributing to the challenge in matching appropriate supply and demand for AT. While ATscale will address many of these, it is also going to require partnership on multiple levels with a coordinated strategic approach across a variety of stakeholders. This collective effort will enable the global community to have an impact greater than the sum of its individual parts in improving access to affordable, appropriate AT globally

Asymmetric Dark Matter and Dark Radiation

Asymmetric Dark Matter (ADM) models invoke a particle-antiparticle asymmetry, similar to the one observed in the Baryon sector, to account for the Dark Matter (DM) abundance. Both asymmetries are usually generated by the same mechanism and generally related, thus predicting DM masses around 5 GeV in order to obtain the correct density. The main challenge for successful models is to ensure efficient annihilation of the thermally produced symmetric component of such a light DM candidate without violating constraints from collider or direct searches. A common way to overcome this involves a light mediator, into which DM can efficiently annihilate and which subsequently decays into Standard Model particles. Here we explore the scenario where the light mediator decays instead into lighter degrees of freedom in the dark sector that act as radiation in the early Universe. While this assumption makes indirect DM searches challenging, it leads to signals of extra radiation at BBN and CMB. Under certain conditions, precise measurements of the number of relativistic species, such as those expected from the Planck satellite, can provide information on the structure of the dark sector. We also discuss the constraints of the interactions between DM and Dark Radiation from their imprint in the matter power spectrum.Comment: 22 pages, 5 figures, to be published in JCAP, minor changes to match version to be publishe

Changes in performance and bio-mathematical model performance predictions during 45 days of sleep restriction in a simulated space mission

Lunar habitation and exploration of space beyond low-Earth orbit will require small crews to live in isolation and confinement while maintaining a high level of performance with limited support from mission control. Astronauts only achieve approximately 6 h of sleep per night, but few studies have linked sleep deficiency in space to performance impairment. We studied crewmembers over 45 days during a simulated space mission that included 5 h of sleep opportunity on weekdays and 8 h of sleep on weekends to characterize changes in performance on the psychomotor vigilance task (PVT) and subjective fatigue ratings. We further evaluated how well bio-mathematical models designed to predict performance changes due to sleep loss compared to objective performance. We studied 20 individuals during five missions and found that objective performance, but not subjective fatigue, declined from the beginning to the end of the mission. We found that bio-mathematical models were able to predict average changes across the mission but were less sensitive at predicting individual-level performance. Our findings suggest that sleep should be prioritized in lunar crews to minimize the potential for performance errors. Bio-mathematical models may be useful for aiding crews in schedule design but not for individual-level fitness-for-duty decisions