First assessment of Mercury (Hg) concentrations in skin and Carapace of Flatback Turtles (Natator depressus) (Garman) from Western Australia

Mercury pollution in the surface ocean has more than doubled over the past century. Within oceanic food webs, sea turtles have life history characteristics that make them especially vulnerable to mercury (Hg) accumulation. In this study we investigated Hg concentrations in the skin and carapace of nesting flatback turtles (Natator depressus) from two rookeries in Western Australia. A total of 50 skin samples and 52 carapace samples were collected from nesting turtles at Thevenard Island, and 23 skin and 28 carapace samples from nesting turtles at Eighty Mile Beach. We tested the influence of turtle size on Hg concentrations, hypothesising that larger and likely older adult turtles would exhibit higher concentrations due to more prolonged exposure to Hg. We compared the rookeries, hypothesising that the turtles from the southern rookery (Thevenard Island) were more likely to forage and reside in the Pilbara region closer to industrial mining activity and loading ports (potential exposure to higher environmental Hg concentrations) with turtles from the northern rookery (Eighty Mile Beach) more likely to reside and feed in the remote Kimberley. Turtles from the Eighty Mile Beach rookery had significantly higher skin Hg concentrations (x̄ = 19.4 ± 4.8 ng/g) than turtles from Thevenard Island (x̄ = 15.2 ± 5.8 ng/g). There was no significant difference in carapace Hg concentrations in turtles between Eighty Mile Beach (x̄ = 48.4 ± 21.8 ng/g) and Thevenard Island (x̄ = 41.3 ± 16.5 ng/g). Turtle size did not explain Hg concentrations in skin samples from Eighty Mile Beach and Thevenard Island, but turtle size explained 43.1% of Hg concentrations in the carapace of turtles from Eighty Mile Beach and 44.2% from Thevenard Island. Mercury concentrations in the flatback turtles sampled in this study are relatively low compared to other sea turtles worldwide, likely a result of the generally low concentrations of Hg in the Australian environment. Although we predicted that mining activities would influence flatback turtle Hg bioaccumulations, our data did not support this effect. This may be a result of foraging ground overlap between the two rookeries, or the predominant wind direction carrying atmospheric Hg inland rather than seaward. This is the first Hg study in skin and carapace of flatback turtles and represents a baseline to compare Hg contamination in Australia’s surrounding oceans

Fas ligand elicits a caspase-independent proinflammatory response in human keratinocytes: implications for dermatitis.

Fas ligand (FasL) causes apoptosis of epidermal keratinocytes and triggers the appearance of spongiosis in eczematous dermatitis. We demonstrate here that FasL also aggravates inflammation by triggering the expression of proinflammatory cytokines, chemokines, and adhesion molecules in keratinocytes. In HaCaT cells and in reconstructed human epidermis (RHE), FasL triggered a NF-kappaB-dependent mRNA accumulation of inflammatory cytokines (tumor necrosis factor-alpha, IL-6, and IL-1beta), chemokines (CCL2/MCP-1, CXCL1/GROalpha, CXCL3/GROgamma, and CXCL8/IL-8), and the adhesion molecule ICAM-1. Oligomerization of Fas was required both for apoptosis and for gene expression. Inhibition of caspase activity abolished FasL-dependent apoptosis; however, it failed to suppress the expression of FasL-induced genes. Additionally, in the presence of caspase inhibitors, but not in their absence, FasL triggered the accumulation of CCL5/RANTES (regulated on activation normal T cell expressed and secreted) mRNA. Our findings identify a novel proinflammatory role of FasL in keratinocytes that is independent of caspase activity and is separable from apoptosis. Thus, in addition to causing spongiosis, FasL may play a direct role in triggering and/or sustaining inflammation in eczemas

Crossover between a displacive and an order-disorder phase transition

The phase transition in a three-dimensional array of classical anharmonic oscillators with harmonic nearest-neighbor coupling (discrete φ 4 model) is studied by Monte Carlo (MC) simulations and by analytical methods. The model allows us to choose a single dimensionless parameter a determining completely the behavior of the system. Changing a from 0 to + ∞ allows to go continuously from the displacive to the order-disorder limit. We calculate the transition temperature T c and the temperature dependence of the order parameter down to T = 0 for a wide range of the parameter a. The T c from MC calculations shows an excellent agreement with the known asymptotic values for small and large a. The obtained MC results are further compared with predictions of the mean-field and independent-mode approximations as well as with predictions of our own approximation scheme. In this approximation, we introduce an auxiliary system, which yields approximately the same temperature behavior of the order parameter, but allows the decoupling of the phonon modes. Our approximation gives the value of T c within an error of 5% and satisfactorily describes the temperature dependence of the order parameter for all values of a

Linking working memory and long-term memory: A computational model of the learning of new words

The nonword repetition (NWR) test has been shown to be a good predictor of children’s vocabulary size. NWR performance has been explained using phonological working memory, which is seen as a critical component in the learning of new words. However, no detailed specification of the link between phonological working memory and long-term memory (LTM) has been proposed. In this paper, we present a computational model of children’s vocabulary acquisition (EPAM-VOC) that specifies how phonological working memory and LTM interact. The model learns phoneme sequences, which are stored in LTM and mediate how much information can be held in working memory. The model’s behaviour is compared with that of children in a new study of NWR, conducted in order to ensure the same nonword stimuli and methodology across ages. EPAM-VOC shows a pattern of results similar to that of children: performance is better for shorter nonwords and for wordlike nonwords, and performance improves with age. EPAM-VOC also simulates the superior performance for single consonant nonwords over clustered consonant nonwords found in previous NWR studies. EPAM-VOC provides a simple and elegant computational account of some of the key processes involved in the learning of new words: it specifies how phonological working memory and LTM interact; makes testable predictions; and suggests that developmental changes in NWR performance may reflect differences in the amount of information that has been encoded in LTM rather than developmental changes in working memory capacity. Keywords: EPAM, working memory, long-term memory, nonword repetition, vocabulary acquisition, developmental change

Spatial gradients in the cosmological constant

It is possible that there may be differences in the fundamental physical parameters from one side of the observed universe to the other. I show that the cosmological constant is likely to be the most sensitive of the physical parameters to possible spatial variation, because a small variation in any of the other parameters produces a huge variation of the cosmological constant. It therefore provides a very powerful {\em indirect} evidence against spatial gradients or temporal variation in the other fundamental physical parameters, at least 40 orders of magnitude more powerful than direct experimental constraints. Moreover, a gradient may potentially appear in theories where the variability of the cosmological constant is connected to an anthropic selection mechanism, invoked to explain the smallness of this parameter. In the Hubble damping mechanism for anthropic selection, I calculate the possible gradient. While this mechanism demonstrates the existence of this effect, it is too small to be seen experimentally, except possibly if inflation happens around the Planck scale.Comment: 12 page

The Importance of Time Congruity in the Organisation.

In 1991 Kaufman, Lane, and Lindquist proposed that time congruity in terms of an individual's time preferences and the time use methods of an organisation would lead to satisfactory performance and enhancement of quality of work and general life. The research reported here presents a study which uses commensurate person and job measures of time personality in an organisational setting to assess the effects of time congruity on one aspect of work life, job-related affective well-being. Results show that time personality and time congruity were found to have direct effects on well-being and the influence of time congruity was found to be mediated through time personality, thus contributing to the person–job (P–J) fit literature which suggests that direct effects are often more important than indirect effects. The study also provides some practical examples of ways to address some of the previously cited methodological issues in P–J fit research

Hard gluon damping in hot QCD

The gluon collisional width in hot QCD plasmas is discussed with emphasis on temperatures near $T_c$, where the coupling is large. Considering its effect on the entropy, which is known from lattice calculations, it is argued that the width, which in the perturbative limit is given by $\gamma \sim g^2 \ln(1/g) T$, should be sizeable at intermediate temperatures but has to be small close to $T_c$. Implications of these results for several phenomenologically relevant quantities, such as the energy loss of hard jets, are pointed out.Comment: uses RevTex and graphic

Buoyancy Energy Storage Technology: An energy storage solution for islands, coastal regions, offshore wind power and hydrogen compression

The world is undergoing a substantial energy transition with an increasing share of intermittent sources of energy on the grid such as wind and solar. These variable renewable energy sources require an energy storage solution to allow a smooth integration of these sources. Batteries can provide short-term storage solutions. However, there is still a need for technologies that can provide weekly energy storage at locations without potential for pumped hydro storage. This paper presents innovative solutions for energy storage based on “buoyancy energy storage” in the deep ocean. The ocean has large depths where potential energy can be stored in gravitational based energy storage systems. The deeper the system, the greater the amount of stored energy. The cost of Buoyancy Energy Storage Technology (BEST) is estimated to vary from 50 to 100 USD/kWh of stored electric energy and 4,000 to 8,000 USD/kW of installed capacity. BES could be a feasible option to complement batteries, providing weekly storage cycles. As well as from storing energy, the system can also be used to compress hydrogen efficiently

Cross-domain interference costs during concurrent verbal and spatial serial memory tasks are asymmetric

Some evidence suggests that memory for serial order is domain-general. Evidence also points to asymmetries in interference between verbal and visual-spatial tasks. We confirm that concurrently remembering verbal and spatial serial lists provokes substantial interference compared with remembering a single list, but we further investigate the impact of this interference throughout the serial position curve, where asymmetries are indeed apparent. A concurrent verbal order memory task affects spatial memory performance throughout the serial positions of the list, but performing a spatial order task affects memory for the verbal serial list only for early list items; in the verbal task only, the final items are unaffected by a concurrent task. Adding suffixes eliminates this asymmetry, resulting in impairment throughout the list for both tasks. These results suggest that domain-general working memory resources may be supplemented with resources specific to the verbal domain, but perhaps not with equivalent spatial resources