Synoptic environment of composite tropical cyclones in the south-west Indian ocean

The composite structure of the tropical cyclone (TC) environment in the South-West Indian Ocean is analysed using European Community medium-range weather data. Conditions suitable for the development of tropical cyclones are present between 5 and 15°S and between 40 and 100°E. Groups of westward-moving and polewardrecurving TCs are used to construct system-following composites from three days before maximum intensity toone day after. The synoptic fields surrounding the westward-moving composite TC remain steady, whereas the recurving composite environment supports rapid vortex growth. Interaction with a subtropical trough is prominentin the recurving TC. The results offer useful insights to weather interactions in the South-West Indian Ocean

Genome annotation for clinical genomic diagnostics: strengths and weaknesses

The Human Genome Project and advances in DNA sequencing technologies have revolutionized the identification of genetic disorders through the use of clinical exome sequencing. However, in a considerable number of patients, the genetic basis remains unclear. As clinicians begin to consider whole-genome sequencing, an understanding of the processes and tools involved and the factors to consider in the annotation of the structure and function of genomic elements that might influence variant identification is crucial. Here, we discuss and illustrate the strengths and weaknesses of approaches for the annotation and classification of important elements of protein-coding genes, other genomic elements such as pseudogenes and the non-coding genome, comparative-genomic approaches for inferring gene function, and new technologies for aiding genome annotation, as a practical guide for clinicians when considering pathogenic sequence variation. Complete and accurate annotation of structure and function of genome features has the potential to reduce both false-negative (from missing annotation) and false-positive (from incorrect annotation) errors in causal variant identification in exome and genome sequences. Re-analysis of unsolved cases will be necessary as newer technology improves genome annotation, potentially improving the rate of diagnosis

Efficient state-based CRDTs by delta-mutation

CRDTs are distributed data types that make eventual consistency of a distributed object possible and non ad-hoc. Specifically, state-based CRDTs ensure convergence through disseminating the entire state, that may be large, and merging it to other replicas; whereas operation-based CRDTs disseminate operations (i.e., small states) assuming an exactly-once reliable dissemination layer. We introduce Delta State Conflict-Free Replicated Datatypes (δ-CRDT) that can achieve the best of both worlds: small messages with an incremental nature, disseminated over unreliable communication channels. This is achieved by defining δ-mutators to return a delta-state, typically with a much smaller size than the full state, that is joined to both: local and remote states. We introduce the δ-CRDT framework, and we explain it through establishing a correspondence to current state-based CRDTs. In addition, we present an anti-entropy algorithm that ensures causal consistency, and two δ-CRDT specifications of well-known replicated datatypes.This work is co-financed by the North Portugal Regional Operational Programme (ON.2, O Novo Norte), under the National Strategic Reference Framework (NSRF), through the European Regional Development Fund (ERDF), within project NORTE07-0124-FEDER-000058; and by EU FP7 SyncFree project (609551)

Topological Surface States Protected From Backscattering by Chiral Spin Texture

Topological insulators are a new class of insulators in which a bulk gap for electronic excitations is generated by strong spin orbit coupling. These novel materials are distinguished from ordinary insulators by the presence of gapless metallic boundary states, akin to the chiral edge modes in quantum Hall systems, but with unconventional spin textures. Recently, experiments and theoretical efforts have provided strong evidence for both two- and three-dimensional topological insulators and their novel edge and surface states in semiconductor quantum well structures and several Bi-based compounds. A key characteristic of these spin-textured boundary states is their insensitivity to spin-independent scattering, which protects them from backscattering and localization. These chiral states are potentially useful for spin-based electronics, in which long spin coherence is critical, and also for quantum computing applications, where topological protection can enable fault-tolerant information processing. Here we use a scanning tunneling microscope (STM) to visualize the gapless surface states of the three-dimensional topological insulator BiSb and to examine their scattering behavior from disorder caused by random alloying in this compound. Combining STM and angle-resolved photoemission spectroscopy, we show that despite strong atomic scale disorder, backscattering between states of opposite momentum and opposite spin is absent. Our observation of spin-selective scattering demonstrates that the chiral nature of these states protects the spin of the carriers; they therefore have the potential to be used for coherent spin transport in spintronic devices.Comment: to be appear in Nature on August 9, 200

A qualitative study of NIMBYism for waste in smaller urban areas of a low-income country, Mzuzu, Malawi

When waste management infrastructure is built, there can be resistance from the local affected populations, often termed the Not in My Backyard (NIMBY) phenomenon. This study aims to understand the forms of resistance that may develop in such contexts, focusing on 2 solid waste and 1 liquid waste management site within Mzuzu City, Malawi. At the newest solid waste site, community resistance had grown to the extent that the site was reportedly destroyed by the local community. Interviews and observations of the sites are complemented by examining historic and recent satellite images. It was found that, at the new solid waste site, community engagement had not been conducted effectively prior to construction and as part of ongoing site operations. This was compounded by poor site management and the non-delivery of the promised benefits to the community. In contrast, at the liquid waste site, the community could access untreated sludge for use as fertilizer and were happier to live within its vicinity. While NIMBYism is a frustrating phenomenon for city planners, it is understandable that communities want to protect their health and well-being when there is a history of mismanagement of waste sites which is sadly common in low-income settings. It is difficult for government agencies to deliver these services and broader waste management. In this study, an unsuccessful attempt to do something better with a legitimate goal is not necessarily a failure, but part of a natural learning process for getting things right

A model of top-down gain control in the auditory system

To evaluate a model of top-down gain control in the auditory system, 6 participants were asked to identify 1-kHz pure tones differing only in intensity. There were three 20-session conditions: (1) four soft tones (25, 30, 35, and 40 dB SPL) in the set; (2) those four soft tones plus a 50-dB SPL tone; and (3) the four soft tones plus an 80-dB SPL tone. The results were well described by a top-down, nonlinear gain-control system in which the amplifier’s gain depended on the highest intensity in the stimulus set. Individual participants’ identification judgments were generally compatible with an equal-variance signal-detection model in which the mean locations of the distribution of effects along the decision axis were determined by the operation of this nonlinear amplification system

Computer simulation of syringomyelia in dogs

Syringomyelia is a pathological condition in which fluid-filled cavities (syringes) form and expand in the spinal cord. Syringomyelia is often linked with obstruction of the craniocervical junction and a Chiari malformation, which is similar in both humans and animals. Some brachycephalic toy breed dogs such as Cavalier King Charles Spaniels (CKCS) are particularly predisposed. The exact mechanism of the formation of syringomyelia is undetermined and consequently with the lack of clinical explanation, engineers and mathematicians have resorted to computer models to identify possible physical mechanisms that can lead to syringes. We developed a computer model of the spinal cavity of a CKCS suffering from a large syrinx. The model was excited at the cranial end to simulate the movement of the cerebrospinal fluid (CSF) and the spinal cord due to the shift of blood volume in the cranium related to the cardiac cycle. To simulate the normal condition, the movement was prescribed to the CSF. To simulate the pathological condition, the movement of CSF was blocked

2023 State of the Commonwealth Report

This is Old Dominion University\u27s ninth annual State of the Commonwealth Report. While it represents the work of many people connected in various ways to the University, the report does not constitute an official viewpoint of Old Dominion, its president, Brian Hemphill, Ph.D., the board of Visitors, the Strome College of Business or the generous donors who support the activities of the Dragas Center for Economic Analysis and Policy. Our work seeks to contribute to the conversation about how Virginia can foster growth across the Commonwealth without glossing over the challenges we face. Instead of retreating into partisan enclaves where affirmation is sought over information, we want to encourage difficult conversations to improve economic outcomes for all of Virginia\u27s residents

Nonminimal Couplings in the Early Universe: Multifield Models of Inflation and the Latest Observations

Models of cosmic inflation suggest that our universe underwent an early phase of accelerated expansion, driven by the dynamics of one or more scalar fields. Inflationary models make specific, quantitative predictions for several observable quantities, including particular patterns of temperature anistropies in the cosmic microwave background radiation. Realistic models of high-energy physics include many scalar fields at high energies. Moreover, we may expect these fields to have nonminimal couplings to the spacetime curvature. Such couplings are quite generic, arising as renormalization counterterms when quantizing scalar fields in curved spacetime. In this chapter I review recent research on a general class of multifield inflationary models with nonminimal couplings. Models in this class exhibit a strong attractor behavior: across a wide range of couplings and initial conditions, the fields evolve along a single-field trajectory for most of inflation. Across large regions of phase space and parameter space, therefore, models in this general class yield robust predictions for observable quantities that fall squarely within the "sweet spot" of recent observations.Comment: 17pp, 2 figs. References added to match the published version. Published in {\it At the Frontier of Spacetime: Scalar-Tensor Theory, Bell's Inequality, Mach's Principle, Exotic Smoothness}, ed. T. Asselmeyer-Maluga (Springer, 2016), pp. 41-57, in honor of Carl Brans's 80th birthda

The State of the Region: Hampton Roads 2023

This is Old Dominion University’s 24th annual State of the Region Report. While it represents the work of many people connected in various ways to the university, the report does not constitute an official viewpoint of Old Dominion, its president, Brian Hemphill, Ph.D., the Board of Visitors, the Strome College of Business or the generous donors who support the activities of the Dragas Center for Economic Analysis and Policy. Over the past year, we have experienced rising interest rates, persistent inflation, and the continued impact of geopolitical shocks on our daily lives. We live, for better or worse, in interesting times and our ability to grow as a region will certainly be tested in the coming years. There is good news to report. The region has largely recovered from the pandemic-related shocks of 2020 and, in some sectors, a new expansion is underway. While the pillars of the regional economy are strong, the region remains overly reliant on federal spending. Whether federal spending will continue to increase over the coming decade is an open question. With this in mind, we dive into the question of whether Hampton Roads can improve its economic performance relative to its peer and aspirant metropolitan regions. We applaud efforts by local and regional organizations to promote economic development, but we also must gauge these efforts against the data. Can we move the needle to diversify our economy, provide improved opportunities to residents, and attract new residents to the area we call home