Clock-Synchronized Clock and Data Recovery to Enable Sub-Nanosecond Optically-Switched Networks

We review the clock-synchronized approach to clock and data recovery, which enables sub-nanosecond switching time in optically switched networks, and explore the impact of factors such as temperature and jitter on performance and scalability

Anomalous Light Scattering by Topological PT{\mathcal{PT}}-symmetric Particle Arrays

Robust topological edge modes may evolve into complex-frequency modes when a physical system becomes non-Hermitian. We show that, while having negligible forward optical extinction cross section, a conjugate pair of such complex topological edge modes in a non-Hermitian $\mathcal{PT}$-symmetric system can give rise to an anomalous sideway scattering when they are simultaneously excited by a plane wave. We propose a realization of such scattering state in a linear array of subwavelength resonators coated with gain media. The prediction is based on an analytical two-band model and verified by rigorous numerical simulation using multiple-multipole scattering theory. The result suggests an extreme situation where leakage of classical information is unnoticeable to the transmitter and the receiver when such a $\mathcal{PT}$-symmetric unit is inserted into the communication channel.Comment: 16 pages, 8 figure

Rethinking constructed action

We aim to demonstrate the importance of defining linguistic phenomena by using constructed action or CA (i.e. a stretch of discourse that represents one role or combination of roles depicting actions, utterances, thought, attitudes and/or feelings of one or more referents) as an example. The problem is that different assumptions about CA have led to some apparent contradictions about the nature of this phenomenon. Based on observations and analyses of the British Sign Language narrative data, we outline criteria and recommendations for defining and analysing CA. We show that, in carefully defining the phenomenon in question and providing criteria for its identification, applying these criteria to usage data leads to emergence of particular types of Constructed Action. We also show how identifying these types can help resolve some of the apparent contradictions in the literature

Structure of isolated Z-disks from honeybee flight muscle

The Z-disk is a complex structure comprising some 40 proteins that are involved in the transmission of force developed during muscle contraction and in important signalling pathways that govern muscle homeostasis. In the Z-disk the ends of antiparallel thin filaments from adjacent sarcomeres are crosslinked by α-actinin. The structure of the Z-disk lattice varies greatly throughout the animal kingdom. In vertebrates the thin filaments form a tetragonal lattice, whereas invertebrate flight muscle has a hexagonal lattice. The width of the Z-disk varies considerably and correlates with the number of α-actinin bridges. A detailed description at a high resolution of the Z-disk lattice is needed in order to better understand muscle function and disease. The molecular architecture of the Z-disk lattice in honeybee (Apis mellifera) is known from plastic embedded thin sections to a resolution of 7 nm, which is not sufficient to dock component protein crystal structures. It has been shown that sectioning is a damaging process that leads to the loss of finer details present in biological specimens. However, the Apis Z-disk is a thin structure (120 nm) suitable for cryo EM. We have isolated intact honeybee Z-disks from indirect flight muscle, thus obviating the need of plastic sectioning. We have employed cryo electron tomography and image processing to investigate the arrangement of proteins within the hexagonal lattice of the Apis Z-disk. The resolution obtained, ~6 nm, was probably limited by damage caused by the harshness of the conditions used to extract the myofibrils and isolate the Z-disks

Goldstinos, Supercurrents and Metastable SUSY Breaking in N=2 Supersymmetric Gauge Theories

We construct an N=2 supersymmetric generalization of the N=1 supercurrent formalism of Komargodski and Seiberg (KS) and use it to show that N=2 theories with linear superconformal anomalies cannot break SUSY under certain broad assumptions. This result suggests that there are no metastable SUSY breaking vacua in a large class of theories that includes N=2 Super Yang-Mills (SYM).Comment: 19 pages; minor revisions; JHEP versio

Home-based toothbrushing interventions for parents of young children to reduce dental caries: A systematic review

Background: Dental caries is the most prevalent preventable condition in children. A key preventive home-based oral health behaviour is the adoption and maintenance of parental supervised toothbrushing until eight years of age. Aim: To examine interventions promoting parental supervised toothbrushing practices to reduce dental caries in young children (<8 years old). Design: Interventions promoting parental involvement in home-based toothbrushing in children under eight years old and their impact on caries were subjected to review. Electronic databases (MEDLINE, EMBASE, PubMed, Web of Science, PsycINFO, Scopus and the Cochrane Library), references and unpublished literature databases were searched for relevant literature. Results: Of the 10,176 articles retrieved, forty-two articles were included. The Theoretical Domains Framework was used to code intervention content, with the main domains addressed being knowledge (41/42), skills (35/42), and environmental context and resources (22/42). Sufficient descriptions of the intervention development, delivery and evaluation were lacking, with only 18 studies being underpinned by theory. Twenty-nine studies explored the impact on caries yielding mixed results. Conclusions: There are few interventions targeting home-based oral health behaviours underpinned by theory and methodological rigour in their development and evaluation. This demonstrates a clear need for future interventions to be guided by complex intervention methodology

Retinoblastoma and vision

The assessment of vision has a growing importance in the management of retinoblastoma in the era of globe-conserving therapy, both prior to and after treatment. As survival rates approach 98-99% and globe salvage rates reach ever-higher levels, it is important to provide families with information regarding the visual outcomes of different treatments. We present an overview of the role of vision in determining the treatment given and the impact of complications of treatment. We also discuss screening and treatment strategies that can be used to maximise vision

Soft Spectrum in Yukawa-Gauge Mediation

We introduce a model independent parametrization for a subclass of gauge mediated theories, which we refer to as Yukawa-gauge mediation. Within this formalism we study the resulting soft masses in the visible spectrum. We find general expressions for the gaugino and scalar masses. Under generic conditions, the gaugino mass is screened, vanishing at first order in the SUSY breaking scale.Comment: 22 pages, 4 figures; v2: minor corrections, published versio

A Bound on the Superpotential

We prove a general bound on the superpotential in theories with broken supersymmetry and broken R-symmetry, 2|W|< f_a F, where f_a and F are the R-axion and Goldstino decay constants, respectively. The bound holds for weakly coupled as well as strongly coupled theories, thereby providing an exact result in theories with broken supersymmetry. We briefly discuss several possible applications.Comment: 20 page