What determines the likelihood of species discovery in marine holozooplankton: is size, range or depth important?

The relationship between date of first description and size, geographic range and depth of occurrence is investigated for 18 orders of marine holozooplankton (comprising over 4000 species). Results of multiple regression analyses suggest that all attributes are linked, which reflects the complex interplay between them. Partial correlation coefficients suggest that geographic range is the most important predictor of description date, and shows an inverse relationship. By contrast, size is generally a poor indicator of description date, which probably mirrors the size-independent way in which specimens are collected, though there is clearly a positive relationship between both size and depth (for metabolic/trophic reasons), and size and geographic range. There is also a positive relationship between geographic range and depth that probably reflects the near constant nature of the deep-water environment and the wide-ranging currents to be found there. Although we did not explicitly incorporate either abundance or location into models predicting the date of first description, neither should be ignored.

Radiolaria: Major exporters of organic carbon to the deep ocean

Very large pulses of particulate organic matter intermittently sink to the deep waters of the open ocean in the Northeast Atlantic. These pulses, measured by moored sediment traps since 1989, can contribute up to 60% of the organic flux to 3000 m in a particular year and are thus a major cause of the variability in carbon sequestration from the atmosphere in the region. Pulses occur in the late summer and are characterized by material that is very rich in organic carbon but with low concentrations of the biominerals opal and calcite. A number of independent lines of evidence have been examined to determine the causes of these pulses: (1) Data from the Continuous Plankton Recorder (CPR) survey show that in this region, radiolarian protozoans intermittently reach high abundances in the late summer just preceding organic pulses to depth. (2) CPR data also show that the interannual variability in radiolarian abundance since 1997 mirrors very closely the variability of deep ocean organic deposition. (3) The settling material collected in the traps displays a strong correlation between fecal pellets produced by radiolaria and the measured organic carbon flux. These all suggest that the pulses are mediated by radiolarians, a group of protozoans found throughout the world’s oceans and which are widely used by paleontologists to determine past climate conditions. Changes in the upper ocean community structure (between years and on longer timescales) may have profound effects on the ability of the oceans to sequester carbon dioxide from the atmosphere.

Patterns of jellyfish abundance in the North Atlantic

A number of explanations have been advanced to account for the increased frequency and intensity at which jellyfish (pelagic cnidarians and ctenophores) blooms are being observed, most of which have been locally directed. Here, we investigate seasonal and inter-annual patterns in abundance and distribution of jellyfish in the North Atlantic Ocean to determine if there have been any system-wide changes over the period 1946–2005, by analysing records of the presence of coelenterates from the Continuous Plankton Recorder (CPR) survey. Peaks in jellyfish abundance are strongly seasonal in both oceanic and shelf areas: oceanic populations have a mid-year peak that is more closely related to peaks in phyto- and zooplankton, whilst the later peak of shelf populations mirrors changes in SST and reflects processes of advection and aggregation. There have been large amplitude cycles in the abundance of oceanic and shelf jellyfish (although not synchronous) over the last 60 years, with a pronounced synchronous increase in abundance in both areas over the last 10 years. Inter-annual variations in jellyfish abundance in oceanic areas are related to zooplankton abundance and temperature changes, but not to the North Atlantic Oscillation or to a chlorophyll index. The long-term inter-annual abundance of jellyfish on the shelf could not be explained by any environmental variables investigated. As multi-decadal cycles and more recent increase in jellyfish were obvious in both oceanic and shelf areas, we conclude that these are likely to reflect an underlying climatic signal (and bottom-up control) rather than any change in fishing pressure (top-down control). Our results also highlight the role of the CPR data in investigating long-term changes in jellyfish, and suggest that the cnidarians sampled by the CPR are more likely to be holoplanktic hydrozoans and not the much larger meroplanktic scyphozoans as has been suggested previously.

Valor social de la fotografía de guerra: Robert Capa en la Guerra civil española

A partir del análisis de las relaciones entre sociología, fotografía y documentación se realiza un recorrido por algunas de las principales fotografías realizadas por Robert Capa durante la Guerra civil española.

Creating and probing multipartite macroscopic entanglement with light

We propose an immediately realizable scheme showing signatures of multipartite entanglement generated by radiation pressure in a cavity system with a movable mirror. We show how the entanglement involving the inaccessible massive object is unraveled by means of field-field quantum correlations and persists within a wide range of working conditions. Our proposal provides an operative way to infer the quantum behavior of a system that is only partially accessible.

Monkey and humans exhibit similar motion-processing mechanisms

Single cell recording studies have resulted in a detailed understanding of motion-sensitive neurons in non-human primate visual cortex. However, it is not known to what extent response properties of motion-sensitive neurons in the non-human primate brain mirror response characteristics of motion-sensitive neurons in the human brain. Using a motion adaptation paradigm, the direction aftereffect, we show that changes in the activity of human motion-sensitive neurons to moving dot patterns that differ in dot density bear a strong resemblance to data from macaque monkey. We also show a division-like inhibition between neural populations tuned to opposite directions, which also mirrors neural-inhibitory behaviour in macaque. These findings strongly suggest that motion-sensitive neurons in human and non-human primates share common response and inhibitory characteristics.

High contrast plasma mirror: spatial filtering and second harmonic generation at 10(19)Wcm(-2)

Recently, the use of plasma optics to improve temporal pulse contrast has had a remarkable impact on the field of high- power laser-solid density interaction physics. Opening an avenue to previously unachievable plasma density gradients in the high intensity focus, this advance has enabled researchers to investigate new regimes of harmonic generation and ion acceleration. Until now, however, plasma optics for fundamental laser reflection have been used in the sub-relativistic intensity regime (10(15) - 10(16)Wcm(-2)) showing high reflectivity (similar to 70%) and good focusability. Therefore, the question remains as to whether plasma optics can be used for such applications in the relativistic intensity regime (> 10(18)Wcm(-2)). Previous studies of plasma mirrors (PMs) indicate that, for 40 fs laser pulses, the reflectivity fluctuates by an order of magnitude and that focusability of the beam is lost as the intensity is increased above 5 x 10(16)Wcm(-2). However, these experiments were performed using laser pulses with a contrast ratio of similar to 10(7) to generate the reflecting surface. Here, we present results for PM operation using high contrast laser pulses resulting in a new regime of operation - the high contrast plasma mirror (HCPM). In this regime, pulses with contrast ratio > 10(10) are used to form the PM surface at > 10(19)Wcm(-2), displaying excellent spatial filtering, reflected near- field beam profile of the fundamental beam and reflectivities of 60 +/- 5%. Efficient second harmonic generation is also observed with exceptional beam quality suggesting that this may be a route to achieving the highest focusable harmonic intensities. Plasma optics therefore offer the opportunity to manipulate ultra-intense laser beams both spatially and temporally. They also allow for ultrafast frequency up-shifting without detrimental effects due to group velocity dispersion (GVD) or reduced focusability which frequently occur when nonlinear crystals are used for frequency conversion.

The plasma mirror - A subpicosecond optical switch for ultrahigh power lasers

Plasma mirrors are devices capable of switching very high laser powers on subpicosecond time scales with a dynamic range of 20–30 dB. A detailed study of their performance in the near-field of the laser beam is presented, a setup relevant to improving the pulse contrast of modern ultrahigh power lasers ~TW–PW!. The conditions under which high reflectivity can be achieved and focusability of the reflected beam retained are identified. At higher intensities a region of high specular reflectivity with rapidly decreasing focusability was observed, suggesting that specular reflectivity alone is not an adequate guide to the ideal range of plasma mirror operation. It was found that to achieve high reflectivity with negligible phasefront distortion of the reflected beam the inequality csDt,lLaser must be met (cs : sound speed, Dt: time from plasma formation to the peak of the pulse!. The achievable contrast enhancement is given by the ratio of plasma mirror reflectivity to cold reflectivity.

Scattering theory of cooling and heating in optomechanical systems

We present a one-dimensional scattering theory which enables us to describe a wealth of effects arising from the coupling of the motional degree of freedom of scatterers to the electromagnetic field. Multiple scattering to all orders is taken into account. The theory is applied to describe the scheme of a Fabry-Perot resonator with one of its mirrors moving. The friction force, as well as the diffusion, acting on the moving mirror is derived. In the limit of a small reflection coefficient, the same model provides for the description of the mechanical effect of light on an atom moving in front of a mirror.

Scattering theory of multilevel atoms interacting with arbitrary radiation fields

We present a generic transfer matrix approach for the description of the interaction of atoms possessing multiple ground state and excited state sublevels with light fields. This model allows us to treat multi-level atoms as classical scatterers in light fields modified by, in principle, arbitrarily complex optical components such as mirrors, resonators, dispersive or dichroic elements, or filters. We verify our formalism for two prototypical sub-Doppler cooling mechanisms and show that it agrees with the standard literature.

Selectable linear or quadratic coupling in an optomechanical system

There has been much interest recently in the analysis of optomechanical systems incorporating dielectric nano- or microspheres inside a cavity field. We analyse here the situation when one of the mirrors of the cavity itself is also allowed to move. We reveal that the interplay between the two oscillators yields a cross-coupling that results in, e.g., appreciable cooling and squeezing of the motion of the sphere, despite its nominal quadratic coupling. We also discuss a simple modification that would allow this cross-coupling to be removed at will, thereby yielding a purely quadratic coupling for the sphere.

Optical Coalescence and Applications in Cavity Quantum Electrodynamics

We investigate a hitherto largely unexplored regime of cavity quantum electrodynamics in which a highly-reflective element positioned between the end-mirrors of a typical Fabry--P\'erot resonator strongly modifies the cavity response function, such that two longitudinal modes with different spatial parity are brought close to frequency degeneracy. We examine applications of this generic `optical coalescence' phenomenon for the generation of enhanced photon--phonon nonlinearities in optomechanics and atom--photon nonlinearities in cavity quantum electrodynamics with strongly-coupled emitters.

Cinematic and Architectonic Space in Tarkovsky's Solaris

Architecture plays an important role in Andrei Tarkovsky’s films in defining the atmosphere of a space and memory of a place. This paper is a study of how the settings in Tarkovsky’s Solaris (1972) are used to provoke and convey feelings to the audience through architectonic space depicting the city, library, home and aspects of the home such as paintings and mirrors. The rooms depicted in Solaris (Fig. 1) are filled with symbolism and detail. They are imbued with a poetic quality rarely seen in cinema. The everyday places of city, library and home in Solaris are given an emotional depth not usually found in these spaces in reality. Solaris is an anomaly among Tarkovsky’s films in that the majority of the narrative takes place in an enclosed built set. Rarely do Tarkovsky spaces exert so much control over the actors’ movements within a meticulously designed and detailed set. This paper analyses how the director uses constructed sets in Solaris to confront our perception of memories, dreams and reality.
The intent of this study is to gain better understanding of the link between architecture and other art forms such as painting and cinema through spatial analysis. This study also relates to our imagination and how we perceive architectonic space portrayed through cinematic images. The architectural theory of Juhani Pallasmaa forms the basis of this paper.

Development of an objective structured clinical examination (OSCE) to assess formulation and extemporaneous dispensing skills in MPharm undergraduates

Background: The use of Objective Structured Clinical Examination (OSCE) in Pharmacy has been explored; however this is the first attempt in Queen’s University School of Pharmacy, Belfast to assess students via this method in a module where chemistry is the main discipline.

Aims: To devise an OSCE to assess undergraduate ability to check extemporaneously dispensed products for clinical and formulation errors. This activity also aims to consider whether it is a viable method of assessment in such a science-based class, from a staff and student perspective.

Method: Students rotated around a number of stations, performing a check of the product, corresponding prescription and formulation record sheet detailing the theory behind the formulation. They were assessed on their ability to spot intentional mistakes at each one.

Results: Of the 79 students questioned, 95% indicated that OSCE made them aware of the importance of the clinical check carried out by the pharmacist. Nearly all of the undergraduates (72 out of 79) felt that OSCE made them aware of the type of mistakes that students make in class. Most (5 out of 7) of the academic team members strongly agreed that it made students aware of ‘point of dispensing’ checks carried out by pharmacists, in addition to helping them to prepare for their exam.

Conclusion: OSCE assesses both scientific and formulation skills, and has increased the diversity of assessment of this module, bringing with it many additional benefits for the undergraduates since it measures their ability to exercise professional judgement in a time- constrained environment and, in this way, mirrors the conditions many pharmacists work within.

The Double Life of Duke of Somerset v Cookson, or a Legal Excavation of the Corbridge Lanx

Duke of Somerset v Cookson (1735) occupies an important place in English legal history as a leading authority for Chancery jurisdiction to order specific delivery of movable property where an award of damages would be inadequate. The property at issue was the Corbridge lanx, now in the British Museum, but then claimed as treasure trove by the duke of Somerset as lord of the manor of Corbridge. This paper re-examines Cookson as the first reported English decision relating to treasure trove, and uses later treasure trove claims by the duke of Somerset's successors to the manor of Corbridge, the dukes of Northumberland, to shed fresh light on the 1735 decision and on the development of treasure trove practice from the eighteenth century onwards.