2D cognitive optical data processing with phase change materials

We demonstrate high-density, multi-level crystallization of a Ge2Sb2Te5 thin film using tightly focused femtosecond laser pulses. The optical reflectivity in each distinct phase states level is characterized for applications in ultra-fast cognitive parallel data processing

Chalcogenide phase change materials for nanoscale switching

Since the demonstration of threshold switching in chalcogenide alloys over forty five years ago, phase change materials have been extensively investigated for switching and data storage applications. Phase change switching is based on the reversible change between crystalline and amorphous states of a material and in many chalcogenides this change of state takes place in nanoseconds

Metamaterial electro-optic switch of nanoscale thickness

We demonstrate an innovative concept for nanoscale electro-optic switching. It exploits the frequency shift of a narrow-band Fano resonance mode in a plasmonic planar metamaterial induced by a change in the dielectric properties of an adjacent chalcogenide glass layer. An electrically stimulated transition between amorphous and crystalline forms of the glass brings about a 150 nm shift in the near-infrared resonance providing transmission modulation with a contrast ratio of 4:1 in a device of subwavelength thickness

Chalcogenide metamaterial phase change all-optical switch of nanoscale thickness

Non-volatile, bi-directional, all-optical switching in a phase-change metamaterial delivers high-contrast transmission and reflection modulation at visible and infrared wavelengths in device structures only ~ λ/8 thick

The link between wildlife trade and the global donkey skin product network

Unsustainable global wildlife trade impacts biodiversity and threatens national and global security, but many aspects of this trade remain opaque. Our study is a novel investigation of the alleged links between the trade in wildlife products and in donkey skins. The global donkey skin trade is a newly prevalent and lucrative business, largely driven by Chinese demand for E-Jiao, a traditional medicine derived from donkey skins. Records of donkey skins being seized alongside other wildlife products lead us to hypothesize that there is a link between these two trades. We identified all donkey skin dealers on seven business-to-business e-commerce websites and obtained 14,949 data points. These were used in a network analysis to demonstrate the structure of the network and reveal the connection between the products, including wild animal and plant products offered alongside donkey skins. We identified at least 13 groups of CITES-listed species in the densely connected donkey skin product network, demonstrated an association between the online trade in wildlife products and donkey skins, and discuss the implications of this overlap—including the potential to shed light on potential novel trade pathways in legal and illegal domestic animal and wildlife trade

Conservation inequality and the charismatic cat: Felis felicis

AbstractConservation resources are limited, making it impossible to invest equally in all threatened species. One way to maximise conservation gains is to focus upon those species with particular public appeal, using them to generate funding and support that could also benefit less charismatic species. Although this approach is already used by many conservation organisations, no reliable metrics currently exist to determine the likely charisma of a given species, and therefore identify the most appropriate targets for such campaigns. Here we use market research techniques on over 1500 people from five continents to assess the relative charisma of different mammals, which factors appear to drive it, and how these patterns vary between countries. Felids and primates emerged as highly favoured species for conservation, with the tiger (Panthera tigris) the top species by a wide margin. Using an information theoretic approach we develop models that successfully predict respondents’ preferences across the entire sample, suggesting global commonalities in the attributes that people prefer for conservation. However, by analysing each country separately we are able to improve our models, thus highlighting the importance of identifying locally specific flagships for conservation. The most important attributes were body size and IUCN status, although the extent of baldness, whether the species was a potential threat to humans and whether the eyes were forward or side facing were also widely important. Several of the key attributes revealed in this study could be extrapolated to nearly all terrestrial mammals, paving the way for a standardised global identification of species likely to prove effective for future conservation campaigns. The public preferred species with which they had affinity and familiarity, and we discuss how these aspects could be increased to promote the under-achievers, whilst maximising the funding potential of the highly charismatic mammals. While the felids are widely regarded as a popular taxonomic group, the great extent to which they appealed to our respondents emphasises their potential as ambassadors for conservation. Indeed, the big cats were so highly rated that we might think of them as one, Felis felicis: a globally powerful flagship for conservation

Gibraltar at the United Nations: Caught between a treaty, the charter and the 'fundamentalism' of the special committee

On account of Spain’s long-standing claim to the sovereignty of the British Overseas Territory of Gibraltar, “the Rock” remains one of sixteen non-self-governing territories on the United Nations list awaiting decolonization. This article examines the principles of self-determination and territorial integrity adopted by the United Nations in consideration of the issue of decolonization as they have been applied to Gibraltar, together with the consequences for the parties concerned. With the fiftieth anniversary of the first United Nations Resolution on decolonization on the horizon and the recent adoption by Gibraltar of what is considered to be a noncolonial constitution, the article suggests that it is timely for the United Nations to consider taking a more flexible approach to Gibraltar’s status that would put to one side Spain’s claim but allow Gibraltar to be removed from the UN list

Getting to the core: Internal body temperatures help reveal the ecological function and thermal implications of the lions’ mane

It has been proposed that there is a thermal cost of the mane to male lions, potentially leading to increased body surface temperatures (Ts), increased sperm abnormalities, and to lower food intake during hot summer months. To test whether a mane imposes thermal costs on males, we measured core body temperature (Tb) continuously for approximately 1 year in 18 free-living lions. There was no difference in the 24-hr maximum Tb of males (n = 12) and females (n = 6), and males had a 24-hr mean Tb that was 0.2 ± 0.1°C lower than females after correcting for seasonal effects. Although feeding on a particular day increased 24-hr mean and 24-hr maximum Tb, this phenomenon was true of both male and female lions, and females had higher 24-hr mean and 24-hr maximum Tb than males, on both days when lions did not feed, and on days when lions did feed. Twenty-four-hour Tb was not influenced by mane length or color, and 24-hr mean Tb was negatively correlated with mane length. These data contradict the suggestion that there exists a thermal cost to male lions in possessing a long dark mane, but do not preclude the possibility that males compensate for a mane with increased heat loss. The increased insulation caused by a mane does not necessarily have to impair heat loss by males, which in hot environments is primarily through respiratory evaporative cooling, nor does in necessarily lead to increased heat gain, as lions are nocturnal and seek shade during the day. The mane may even act as a heat shield by increasing insulation. However, dominant male lions frequent water points more than twice as often as females, raising the possibility that male lions are increasing water uptake to facilitate increased evaporative cooling. The question of whether male lions with manes compensate for a thermal cost to the mane remains unresolved, but male lions with access to water do not have higher Tb than females or males with smaller manes.EM201