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The formulation of the mean-field infinite-dimensional solution of hard sphere glasses is a significant milestone for theoretical physics. How relevant this description might be for understanding low-dimensional glass-forming liquids, however, remains unclear. These liquids indeed exhibit a complex interplay between structure and dynamics, and the importance of this interplay might only slowly diminish as dimension d increases. A careful numerical assessment of the matter has long been hindered by the exponential increase in computational costs with d. By revisiting a once common simulation technique involving the use of periodic boundary conditions modeled on Dd lattices, we here partly sidestep this difficulty, thus allowing the study of hard sphere liquids up to d = 13. Parallel efforts by Mangeat and Zamponi [Phys. Rev. E 93, 012609 (2016)] have expanded the mean-field description of glasses to finite d by leveraging the standard liquid–state theory and, thus, help bridge the gap from the other direction. The relatively smooth evolution of both the structure and dynamics across the d gap allows us to relate the two approaches and to identify some of the missing features that a finite-d theory of glasses might hope to include to achieve near quantitative agreement. [ABSTRACT FROM AUTHOR]

Genetic linkage maps provide a useful resource for non-model genomes and can aid in genome reassembly to form more contiguous pseudo-chromosomes. We present the first linkage map of any cephalopod, H. maculosa, composed of 47 linkage groups (LG). A total of 2166 single nucleotide polymorphisms and 2455 presence–absence variant loci were utilised by Lep-Map3 in linkage map construction. The map length spans 2016.62 cM with an average marker distance of 0.85 cM. Integration of the recent H. maculosa genome allowed 1151 scaffolds comprising 34% of the total genomic sequence to be orientated and/or placed using 1278 markers across all 47 LG. The linkage map generated provides a new perspective on HOX gene distribution in octopods. In the H. maculosa linkage map three (SCR, LOX4 and POST1) of six identified HOX genes (HOX1/LAB, SCR, LOX2, LOX4, LOX5, POST1) were located within the same LG (LG 9). The generation of a linkage map for H. maculosa has provided a valuable resource for understanding the evolution of cephalopod genomes and will provide a base for future work. [ABSTRACT FROM AUTHOR]

Social recognition is the ability of individuals in a species to differentiate among conspecifics based on their identity or biologically meaningful demographic. Despite evidence that they have sophisticated brains, complex behavioural repertoires, and acute sensory processing, surprisingly little is known about mechanisms aiding social recognition in cephalopods. This class's unique chemotactile sense by the ventral arm surfaces gathers considerable information used in predator–prey interactions. Does it also help mediate social interactions? This study utilised 366 h of focal animal observations to assess the likelihood of Hapalochlaena maculosa, a nocturnal species, to retreat after physically contacting conspecifics based on their sex, familiarity and mating history. Females retreated from both sexes equally, while males were more likely to retreat after contacting female conspecifics. Most conspicuously, males were significantly more likely to retreat after contacting females with which they had already mated. These findings provide the first evidence for chemotactile sex discrimination and mate recognition within cephalopods, and supplement previous observations that male H. maculosa do not appear to detect the sex of conspecifics from a distance. The decision to retreat from or stay with an individual based on their sex or mating history, only after physical contact, emphasises the importance of chemotactile behaviour in octopus sensory ecology and behaviour. Furthermore, male octopuses have limited spermatophore production, and the use of chemotactile social recognition observed here may highlight the importance of reproduction, specifically sperm allocation and avoidance of sexual cannibalism, on the evolution of sensory ecology and cognition within this lineage. [ABSTRACT FROM AUTHOR]

In this contribution we consider the visualization of global, deep Earth volume datasets for display and researcher interaction. While the algorithms and data analysis techniques that produce such volumetric results have become more sophisticated, the manner of visualizing these findings can be improved. We address the challenge of making an illustrative, exploratory visualization of a global geoscience dataset using a combined seismic tomography result, the primary means by which geoscientists infer structure and process in the deep Earth. We present a novel, interactive graphical application suite and associated workflow that uses an intuitive 2.5D layer compositing approach. This allows the user to adjust the separation between data-slices, control graphics variables such as color mapping, opacity and compositing, and facilitate exploration and annotation of the architecture of the lithosphere. Graphics outputs from our applications are enabled for immersive systems such as dome displays. In a case study we visualize the deep Earth structure beneath the Indian Ocean region. We anticipate that the application methodology will find use in the visualization of multiple datasets representing aspects of the Earth's deep interior and atmosphere, and in the interaction with the increasing number of rich datasets from missions to our neighboring planets. [ABSTRACT FROM AUTHOR]

Area-based measurements of snow water equivalent (SWE) are important for understanding earth system processes such as glacier mass balance, winter hydrological storage in drainage basins, and ground thermal regimes. Remote sensing techniques are ideally suited for wide-scale area-based mapping with the most commonly used technique to measure SWE being passive microwave, which is limited to coarse spatial resolutions of 25 km or greater and to areas without significant topographic variation. Passive microwave also has a negative bias for large SWE. Another method is repeat-pass synthetic aperture radar interferometry (InSAR) that allows measurement of SWE change at much higher spatial resolution. However, it has not been widely adopted because (1) the phase unwrapping problem has not been robustly addressed, especially for interferograms with poor coherence, and (2) SWE change maps scaled directly from repeat-pass interferograms are not an absolute measurement but contain unknown offsets for each contiguous coherent area. We develop and test a novel method for repeat-pass InSAR-based dry-snow SWE estimation that exploits the sensitivity of the dry-snow refraction-induced InSAR phase to topographic variations. The method robustly estimates absolute SWE change at spatial resolutions of < 1 km without the need for phase unwrapping. We derive a quantitative signal model for this new SWE change estimator and identify the relevant sources of bias. The method is demonstrated using both simulated SWE distributions and a 9-year RADARSAT-2 (C-band, 5.405 GHz) spotlight-mode dataset near Inuvik, Northwest Territories (NWT), Canada. SWE results are compared to in situ snow survey measurements and estimates from ERA5 reanalysis. Our method performs well in high-relief areas, thus providing complementary coverage to passive-microwave-based SWE estimation. Further, our method has the advantage of requiring only a single wavelength band and thus can utilize existing spaceborne synthetic aperture radar systems. [ABSTRACT FROM AUTHOR]

Although much is known about the metastable liquid branch of hard spheres—from low dimension d up to d → ∞ —its crystal counterpart remains largely unexplored for d > 3 . In particular, it is unclear whether the crystal phase is thermodynamically stable in high dimensions and thus whether a mean-field theory of crystals can ever be exact. In order to determine the stability range of hard sphere crystals, their equation of state is here estimated from numerical simulations, and fluid-crystal coexistence conditions are determined using a generalized Frenkel–Ladd scheme to compute absolute crystal free energies. The results show that the crystal phase is stable at least up to d = 10 , and the dimensional trends suggest that crystal stability likely persists well beyond that point. [ABSTRACT FROM AUTHOR]

The similarity in mechanical properties of dense active matter and sheared amorphous solids has been noted in recent years without a rigorous examination of the underlying mechanism. We develop a mean-field model that predicts that their critical behavior--as measured by their avalanche statistics--should be equivalent in infinite dimensions up to a rescaling factor that depends on the correlation length of the applied field. We test these predictions in two dimensions using a numerical protocol, termed "athermal quasistatic random displacement," and find that these mean-field predictions are surprisingly accurate in low dimensions. We identify a general class of perturbations that smoothly interpolates between the uncorrelated localized forces that occur in the high-persistence limit of dense active matter and system-spanning correlated displacements that occur under applied shear. These results suggest a universal framework for predicting flow, deformation, and failure in active and sheared disordered materials. [ABSTRACT FROM AUTHOR]

Table II appears correct below. This article was originally published online on 4 April 2022 with an error in Table II. [Extracted from the article]

Aufeis, also known as an icing or naled, is an accumulation of ice that forms primarily during winter when water is expelled onto frozen ground or ice surfaces and freezes in layers. Process‐oriented aufeis research initially expanded in the 20th century, but recent interest in changing hydrological conditions in permafrost regions has rejuvenated this field. Despite its societal relevance, the controls on aufeis distribution and dynamics are not well defined and this impedes projections of variation in aufeis size and distribution expected to accompany climate change. This paper reviews the physical controls on aufeis development, current broad‐scale aufeis distribution and anticipated change, and approaches to aufeis investigation. We propose an adjustment to terminology to better distinguish between the formation process and resulting ice bodies, a clarification of the aufeis classification approach based on source water, and a size threshold for broad‐scale aufeis inventory to facilitate collaborative research. We identify additional objectives for future research including advancing process knowledge at fine spatial scales, describing broad‐scale distribution using current remote sensing capabilities, and improving our understanding and predictive capacity over the interactions between aufeis and landscape‐scale permafrost, hydrogeological, geotectonic, and climate conditions. [ABSTRACT FROM AUTHOR]

The cephalopods (Mollusca: Cephalopoda) are an exceptional class among the invertebrates, characterised by the advanced development of their conditional learning abilities, long-term memories, capacity for rapid colour change and extremely adaptable hydrostatic skeletons. These traits enable cephalopods to occupy diverse marine ecological niches, become successful predators, employ sophisticated predator avoidance behaviours and have complex intraspecific interactions. Where studied, observations of cephalopod mating systems have revealed detailed insights to the life histories and behavioural ecologies of these animals. The reproductive biology of cephalopods is typified by high levels of both male and female promiscuity, alternative mating tactics, long-term sperm storage prior to spawning, and the capacity for intricate visual displays and/or use of a distinct sensory ecology. This review summarises the current understanding of cephalopod reproductive biology, and where investigated, how both pre-copulatory behaviours and post-copulatory fertilisation patterns can influence the processes of sexual selection. Overall, it is concluded that sperm competition and possibly cryptic female choice are likely to be critical determinants of which individuals' alleles get transferred to subsequent generations in cephalopod mating systems. Additionally, it is emphasised that the optimisation of offspring quality and/or fertilisation bias to genetically compatible males are necessary drivers for the proliferation of polyandry observed among cephalopods, and potential methods for testing these hypotheses are proposed within the conclusion of this review. Further gaps within the current knowledge of how sexual selection operates in this group are also highlighted, in the hopes of prompting new directions for research of the distinctive mating systems in this unique lineage. [ABSTRACT FROM AUTHOR]

We report a method for overcoming the low stability of nitroalkynes through the development of nitrated vinyl silyltriflate equivalents. Because of their instability, nitroalkynes have only rarely been utilized in synthesis. The reactivity of these silyltriflates, which are prepared in situ, is exemplified by dipolar cycloaddition reactions with nitrones to give highly substituted 4-nitro-4-isoxazolines in high yields. This approach has proven general for several different alkyl and aryl substituted alkynes. In order to minimize the accumulation of potentially hazardous reaction intermediates, we have also developed a continuous flow variant of this method that is capable of carrying out the entire reaction sequence in a good yield and a short residence time. [ABSTRACT FROM AUTHOR]

We report a method for overcoming the low stability of nitroalkynes through the development of nitrated vinyl silyltriflate equivalents. Because of their instability, nitroalkynes have only rarely been utilized in synthesis. The reactivity of these silyltriflates, which are prepared in situ, is exemplified by dipolar cycloaddition reactions with nitrones to give highly substituted 4-nitro-4-isoxazolines in high yields. This approach has proven general for several different alkyl and aryl substituted alkynes. In order to minimize the accumulation of potentially hazardous reaction intermediates, we have also developed a continuous flow variant of this method that is capable of carrying out the entire reaction sequence in a good yield and a short residence time. [ABSTRACT FROM AUTHOR]

Technological advances have an important role in the design of greener synthetic processes. In this Personal Account, we describe a wide range of thermal, photochemical, catalytic, and biphasic chemical transformations examined by our group. Each of these demonstrate how the merits of a continuous flow synthesis platform can align with some of the goals put forth by the Twelve Principles of Green Chemistry. In particular, we illustrate the potential for improved reaction efficiency in terms of atom economy, product yield and reaction rates, the ability to design synthetic process with chemical and solvent waste reduction in mind as well as highlight the benefits of the real-time monitoring capabilities in flow for highly controlled synthetic output. [ABSTRACT FROM AUTHOR]

Continuous flow reactors are enabling tools that can significantly benefit chemical reactions, especially those that are path length dependent (e.g., photochemical), mixing or transport dependent (e.g., gas-liquid), exothermic, or utilize hazardous or unstable intermediates. In this review, it is demonstrated how the nearly instantaneous mixing, exceptionally fast mass transfer, safe access to high temperatures and pressures, and high surface area to volume ratio can be leveraged to improve product yield, reaction rates and/or selectivity. By showcasing five synthetic methodologies examined by our group, it is hoped that the reader will gain an appreciation of the accessible and transformative nature of flow chemistry for improving existing transformations, enabling rapid optimization, and for developing new methodologies that depend on precise parameter controls. [ABSTRACT FROM AUTHOR]

Chemoreception cues potentially influence intraspecific interactions of cephalopods, including mate choice. However, at present there is limited empirical evidence demonstrating whether cephalopods can use olfaction to identify the sex or identity of conspecifics. This study examined the responses of the southern blueringed octopus, Hapalochlaena maculosa (Hoyle, 1883), to conspecific odours during controlled laboratory trials. The ventilation rates in aquaria of 25 wild-sourced animals were measured during four treatments: baseline, sea water, sea water containing male conspecific odour and sea water containing female conspecific odour. When used as 'receivers' in trials, female H. maculosa significantly increased their ventilation rates in response to male odours, but not to female odours. However, female response decreased signifi- cantly with the receiver's size during female-odour treatments. The ventilation rates of male H. maculosa were statistically similar in all treatments. However, their ventilation rates showed a significant progressive increase over the observation period during male and female-odour treatments. Eighteen of these animals (nine females and nine males) were used in focal-animal trials 1 week after odour-cue experiments. Of these individuals, females were significantly more receptive to copulation attempts, and spent significantly more time per day in copulation, with males whose odours had elicited a weaker ventilation response in prior trials. These results suggest that female H. maculosa can use chemosensory cues to discriminate the sex, and possibly identity, of conspecifics and that this information might influence their mate choice. However, the mechanisms underlying these responses and subsequent copulatory access to females by males remain unknown. [ABSTRACT FROM AUTHOR]

The southern blue-ringed octopus, Hapalochlaena maculosa Hoyle (1883), is a nocturnal species that exhibits a mating system in which females hold sperm from multiple males over a one to two month breeding window before laying a single egg clutch. Contrary to most studied animal mating systems where anisogamy exists, gamete package production is limited for both males and females of this species (approx. 50 spermatophores/eggs). This presents an animal model for studying aspects of sperm competition and dynamic mate choice behaviours. The present study reports on the mating behaviour of H. maculosa observed under laboratory conditions using infrared closedcircuit television video footage. Rates of male copulation attempts increased with male size, while female receptivity to mating attempts increased with female size, resulting in larger animals of both sexes gaining more copulations and spending more time per day in copulation. There was some evidence of female preference of larger males, but no male preference of females based on measured morphological traits. Both sexes terminated copulations in equal frequencies but maleterminated copulations were significantly shorter in duration. Males were more likely to terminate copulation early with females they had previously mated with, however were less likely to do so if the female had recently mated with a different male. Among male-terminated copulations, males mated for longer with females that had previously mated with other males in the trial. Male- male mounts were as common as male-female mounts, suggesting that male H. maculosa are not able to discriminate the sex of conspecifics. These findings suggest male strategic allocation of spermatophores based female mating history is an important factor influencing mating behaviours of this species. [ABSTRACT FROM AUTHOR]

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ABSTRACT Saturated floodplains in Arctic deltas provide conditions favourable for frost mound growth. Little work has been reported from these settings to determine the origin of frost mounds and the controls on their distribution, to assess the longevity of individual mounds, or to quantify variation of mound distribution over time. A case study is presented on low mounds in low-centred syngenetic ice-wedge polygons of Big Lake Delta Plain, outer Mackenzie Delta. In 2008 and 2009, 12 mounds were examined by drilling to describe their morphologic variations and to investigate their growth processes. The mounds, containing a core of ice 15 to 58 cm thick, were less than 1 m high and 3 · 7 to 8 · 5 m in diameter; other mounds were over 10 m long. Organic inclusions in the ice, bubble densities, electrical conductivity profiles, and ice-crystal structure indicated that the mounds were hydrostatic frost blisters. Up to six frost blisters were found within individual polygons due to the relatively small volume of water needed to create each mound. Frost-blister densities, of greater than 1700 km-2, increased toward the wet centres of alluvial islands down gentle topographic gradients. The frost blisters were perennial, with individuals remaining identifiable on aerial photographs and satellite images for up to 10 years. Frost blisters collapsed along dilation cracks opened by hydrostatic uplift and by thawing from their sides caused by snow drifting and water ponding. Cyclical growth and decay of the mounds may degrade the visible polygonal network over time. Copyright © 2013 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

We report mass and conductance adsorption isotherms of Kr on individual, single-walled, suspended carbon nanotubes for 53 K< T<90 K for several devices, and of He for 5 K< T<8 K for two devices. Different nanotubes, probably of different diameter and/or chirality, yield different phase diagrams, full monolayer coverages, and partial wetting characteristics for Kr. The He results show, for one of the devices, a greatly reduced heat of adsorption as compared to the well studied system of He on graphite. [ABSTRACT FROM AUTHOR]

The deliberate addition of Gaussian noise to cochlear implant signals has previously been proposed to enhance the time coding of signals by the cochlear nerve. Potentially, the addition of an inaudible level of noise could also have secondary benefits: it could lower the threshold to the information-bearing signal, and by desynchronization of nerve discharges, it could increase the level at which the information-bearing signal becomes uncomfortable. Both these effects would lead to an increased dynamic range, which might be expected to enhance speech comprehension and make the choice of cochlear implant compression parameters less critical (as with a wider dynamic range, small changes in the parameters would have less effect on loudness). The hypothesized secondary effects were investigated with eight users of the Clarion cochlear implant; the stimulation was analogue and monopolar. For presentations in noise, noise at 95% of the threshold level was applied simultaneously and independently to all the electrodes. The noise was found in two-alternative forced-choice (2AFC) experiments to decrease the threshold to sinusoidal stimuli (100 Hz, 1 kHz, 5 kHz) by about 2.0 dB and increase the dynamic range by 0.7 dB. Furthermore, in 2AFC loudness balance experiments, noise was found to decrease the loudness of moderate to intense stimuli. This suggests that loudness is partially coded by the degree of phase-locking of cochlear nerve fibers. The overall gain in dynamic range was modest, and more complex noise strategies, for example, using inhibition between the noise sources, may be required to get a clinically useful benefit. [ABSTRACT FROM AUTHOR]

A procedure for the synthesis of oxazolidinone and tosyl enamines is reported. Alkynoyl oxazolidinones and tosyl imides undergo reaction to form enamines in the presence of catalytic amounts of tertiary amines. The data suggest that an amide anion is formed during the reaction, which undergoes conjugate addition to form the final product. [ABSTRACT FROM AUTHOR]

A procedure for the synthesis of oxazolidinone and tosyl enamines is reported. Alkynoyl oxazolidinones and tosyl imides undergo reaction to form enamines in the presence of catalytic amounts of tertiary amines. The data suggest that an amide anion is formed during the reaction, which undergoes conjugate addition to form the final product. [ABSTRACT FROM AUTHOR]

Comments on several articles about psychiatry. Study of psychiatry in areas of banking and assessment of policies of the World Bank; Discussion on the training and education of psychiatrists.

Deals with issues related to literature. Information on the engravings of Jacques Callot; Meaning of the phrase 'to go it baldheaded'; Identification of the terminal illness of William Perry II of Maryland.

Presents several literary queries. Introduction written by author John P. Marquand for a book by writer Heinz Rettig; Identification of the title, date and place of publication of an essay or biography of Johann Strauss written by I. Schnitzer; Author of a certain 15-line sonnet.

Presents queries on several reference sources. Information on the book 'Lincoln Day By Day, 1861-1865,' vol. 3, by C. Percy Howell; Meaning of the term catskill humor used in the 'New York Times Magazine.'