For the most part, molecular markers and detection of quantitative trait loci have been developed for forest tree species in view to performing marker-assisted selection (MAS). However, MAS has not ...been applied to forest trees until now. In parallel, some success stories of MAS in crop breeding have been reported. Recently, genotyping techniques have undergone a tremendous increase in throughput, moving the trend from MAS to genomic selection. We analyzed 250 papers reporting the use of MAS in plant breeding and found that the most popular schemes used were gene pyramiding and marker-assisted backcross manipulating a single or very few genomic regions which have a major impact on crop value. We reviewed theoretical and simulation studies to identify the parametric space in which MAS is expected to bring about significant advantages over phenotypic selection. Then, we tried to explain why MAS has not been applied to forest trees and discuss the opportunities offered by recent advances in these species.
We treat the dynamical behavior of the continuous elastoplastic model of Masing, consisting of an infinite number of springs and dry-friction elements. Using the theory of differential inclusions we ...prove existence and uniqueness result. Moreover, we prove that the continuous model is the limit of the discrete Masing model when the number of degrees of freedom tends to infinity. Starting from known results of numerical analysis, we build an implicit Euler-like numerical scheme of order one.
Nightmares are often associated with psychiatric disorders and acute stress. This study explores how the COVID‐19 pandemic may have influenced the content of nightmares. A sample of N = 419 US adults ...completed online surveys about sleep and COVID‐19 experiences. Participants were asked about the degree to which they agreed with statements linking greater general stress, worse overall sleep and more middle‐of‐the‐night insomnia with the COVID‐19 pandemic. They were also asked if, during the pandemic, they experienced nightmares related to various themes. Logistic regression analyses examined each nightmare content as outcome and increased stress, worse sleep and more middle‐of‐the‐night insomnia as predictors, adjusted for age, sex and race/ethnicity. Those who reported greater general COVID‐related stress were more likely to have nightmares about confinement, failure, helplessness, anxiety, war, separation, totalitarianism, sickness, death, COVID and an apocalypse. Those who reported worsened sleep were more likely to have nightmares about confinement, oppression, failure, helplessness, disaster, anxiety, evil forces, war, domestic abuse, separation, totalitarianism, sickness, death, COVID and an apocalypse. Those who reported worsened middle‐of‐the‐night insomnia were more likely to have nightmares about confinement, oppression, failure, helplessness, disaster, anxiety, war, domestic abuse, separation, totalitarianism, sickness, death, COVID and an apocalypse. These results suggest that increased pandemic‐related stress may induce negatively‐toned dreams of specific themes. Future investigation might determine whether (and when) this symptom indicates an emotion regulation mechanism at play, or the failure of such a mechanism.
Concerns around the externalities resulting from transport are leading to a reassessment of our mobility options. By reference to policy priorities, it is concluded that there will be an emerging ...demand for smaller and lighter vehicles. Within Europe these will be of the L6e and L7e category. However, the crash safety of these vehicles presents an impediment to their broader commercialisation, acceptance, and further development. The authors identify a number of concerns associated with the approaches to crash safety assessment being discussed and promoted by stakeholders. These concerns include: cascading down M1 category test requirements to the L6e and L7e category would be inefficient as there is little inclination at present to develop, manufacture and market small and lightweight M1 category vehicles; subjecting the L6e and L7e category vehicles to the same crash test and test performance requirements as an M1 category passenger car would not result in comparable performance in single vehicle or vehicle-to-vehicle collisions; and vehicle use cases will differ leading to different accident patterns and questioning the efficacy of the existing M1 category test approach for these smaller and lighter vehicles. To improve the safety of lightweight vehicles would require an innovative test and assessment framework that provides benefits to consumers, producers and society. As a contribution to this framework, an approach is proposed for the assessment of crashworthiness that: responds to the immediate concerns around the safety performance in frontal collisions; aligns with the emerging capabilities of the L-category industry; and provides the consumer with a new mobility option that responds positively to key externalities associated with our use and consumption of transport. The proposed assessment is discussed and is shown to provide equivalent compartment strength to a mid-sized M1 category passenger car – thereby addressing a key concern about compartment integrity in collisions with larger and heavier vehicles.
•Through reference to policy, identifies the key externalities driving transport change.•Discusses the safety problems in accidents presented by smaller and lighter vehicles.•Develops a proposed assessment for crashworthiness of smaller and lightweight vehicles.•Discusses benefits of proposed approach to consumers, producers and society.
Little is known about the symptoms, signs, and management guidelines for children under the age of 6 years after they sustain a concussion. Caregivers of such young children may have unique concerns ...and encounter different challenges from those of school-age children given the distinctive developmental characteristics of the early childhood period. This study aimed to explore the experience of caregivers through semistructured interviews to inform clinical practice.
Fifty caregivers of children aged 6 months to 5.99 years were interviewed 3 months postinjury for this qualitative study to document their experience in relation to their child's accident, recovery, and healthcare provisions.
Four main themes were identified: (1) visible changes associated with caregiver concerns, (2) a roller-coaster of emotions after the injury, (3) healthcare providers' role in addressing the need for reassurance, and (4) the need for better information after the injury.
The findings provide critical insight into the unique experiences and information needs of caregivers of young children who sustain concussion. The challenges identified can inform healthcare professionals regarding the needs of caregivers after early concussion and contribute to building a knowledge base for the development of age-appropriate anticipatory guidance for caregiver mental health and child recovery.
We present 450 and 850 m submillimeter continuum observations of the IC 5146 star-forming region taken as part of the James Clerk Maxwell Telescope Gould Belt Survey. We investigate the location of ...bright submillimeter (clumped) emission with the larger-scale molecular cloud through comparison with extinction maps, and find that these denser structures correlate with higher cloud column density. Ninety-six individual submillimeter clumps are identified using FellWalker, and their physical properties are examined. These clumps are found to be relatively massive, ranging from 0.5 to 116 with a mean mass of 8 and a median mass of 3.7 . A stability analysis for the clumps suggests that the majority are (thermally) Jeans stable, with . We further compare the locations of known protostars with the observed submillimeter emission, finding that younger protostars, i.e., Class 0 and I sources, are strongly correlated with submillimeter peaks and that the clumps with protostars are among the most Jeans unstable. Finally, we contrast the evolutionary conditions in the two major star-forming regions within IC 5146: the young cluster associated with the Cocoon Nebula and the more distributed star formation associated with the Northern Streamer filaments. The Cocoon Nebula appears to have converted a higher fraction of its mass into dense clumps and protostars, the clumps are more likely to be Jeans unstable, and a larger fraction of these remaining clumps contain embedded protostars. The Northern Streamer, however, has a larger number of clumps in total and a larger fraction of the known protostars are still embedded within these clumps.
We present observations of the Cepheus Flare obtained as part of the James Clerk Maxwell Telescope (JCMT) Gould Belt Legacy Survey (GBLS) with the SCUBA-2 instrument. We produce a catalogue of ...sources found by SCUBA-2, and separate these into starless cores and protostars. We determine masses and densities for each of our sources, using source temperatures determined by the Herschel Gould Belt Survey. We compare the properties of starless cores in four different molecular clouds: L1147/58, L1172/74, L1251 and L1228. We find that the core mass functions for each region typically show shallower-than-Salpeter behaviour. We find that L1147/58 and L1228 have a high ratio of starless cores to Class II protostars, while L1251 and L1174 have a low ratio, consistent with the latter regions being more active sites of current star formation, while the former are forming stars less actively. We determine that if modelled as thermally supported Bonnor-Ebert spheres, most of our cores have stable configurations accessible to them. We estimate the external pressures on our cores using archival 13CO velocity dispersion measurements and find that our cores are typically pressure confined, rather than gravitationally bound. We perform a virial analysis on our cores, and find that they typically cannot be supported against collapse by internal thermal energy alone, due primarily to the measured external pressures. This suggests that the dominant mode of internal support in starless cores in the Cepheus Flare is either non-thermal motions or internal magnetic fields.
We first describe the model of a forced pendulum with viscousdamping and Coulomb friction. Then we show that a unique local solutionof the mathematically well-posed problem exists. An adapted ...numericalscheme is built. Attention is devoted to the study of the nonlinearbehaviour of a pendulum via a numerical scheme with small constant timesteps. We describe the global behaviour of the free and forcedoscillations of the pendulum due to friction. We show that chaoticbehaviour occurs when friction is not too large. Lyapunov exponents arecomputed and a Melnikov relation is obtained as a limit of regularisedCoulomb friction. For larger friction, asymptotic behaviour correspondsto equilibrium.
First, results on existence of solutions and their numerical approximations are given for the studied models. Some results of the identification of hysteretic discrete mechanical systems with damping ...submitted to deterministic or stochastic forcing are given. The identification is obtained thanks to hysteresis cycles which are convex or nonconvex.
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