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Aim: The island species–area relationship (ISAR) assumes that the area of islands is homogeneous, or scales with environmental heterogeneity across an archipelago, which is not always the case. We compare the performance of models that adjust or substitute for island area with measures of habitat diversity, island age and resource availability for two taxonomic groups. Location: Five hotspot archipelagos (Azores, Galapagos, Hawaii, Cape Verde, Canary Islands). Taxa: Vascular plants, birds. Methods: We used the mathematical framework of the power law to compare relevant models, treating the one containing only area as a null model against which others were compared. Data were collated from databases and the literature. Models were compared using linear regression within archipelagos and via mixed effect models with archipelago as a random effect. Results: Weighting of island area by habitat diversity and resource availability systematically improved statistical significance and model fits versus the area only power law. Models including island age did not show the same systematic improvement in model fits. For vascular plants, weighting islands by resource availability (energy and water) performed better than weighting by habitat diversity, although for birds these weightings performed equally well. Main Conclusions: Given that islands within archipelagos are fairly heterogeneous in climate, topography and geology, it is worth accounting for this in ISARs. Our results suggest that, for islands in volcanic hotspot archipelagos, this is best done by using direct measures of habitat diversity and resource availability rather than using island age as a proxy. We, therefore, recommend using direct measures, rather than proxies, when investigating the drivers of biodiversity patterns on islands. [ABSTRACT FROM AUTHOR]

Aim: The General Dynamic Model of island biogeography (GDM) explains patterns of species richness on volcanic hotspot archipelagos with respect to island age (T) and area (A), most commonly employing what we here call semi‐log ATT2 and LogATT2 models. These can be considered direct extensions of semi‐log and power law species‐area relationships (SARs), with a hump‐shaped function of T modelling drivers of biodiversity over and above area per se. We compare these and related models and investigate their conceptual and mathematical connections. Location: The Azores, Galapagos, Hawaii, Marquesas, Society Islands, Cape Verde Islands, Canary Islands and Aeolian archipelagos. Taxa: Vascular plants, birds, bryophytes, arthropods and molluscs. Methods: We gathered species richness data from databases and published sources, resulting in 34 datasets for various taxa. We used the Akaike information criterion corrected for small sample size (AICc) to compare the relative performance of models. We analysed the data at archipelago level and across archipelagos by using mixed effect models. We also calculated the relative time of expected peak diversity (Tpeak) from parameter estimates. Results: In almost three‐fourth of the cases the best model overall was one that contained only A or T rather than both predictors. There was greater variance between taxa than between archipelagos. Better dispersed taxa tended to reach peak diversity earlier. The most generally applicable of the models including T were the LogATT2 and LogTT2 models. These have important, previously unrecognized mathematical properties. Main Conclusions: SARs and species–time relationships should always be considered as potentially more parsimonious options. Considering the LogATT2 model as a modification of the power law S = cAz, where a lognormal function in T replaces the constant, c allows the construction of an extended framework for the GDM with incorporation of additional predictors such as measures of environmental heterogeneity and application beyond hotspot archipelagos. [ABSTRACT FROM AUTHOR]

Here the controlled growth of SnSe nanowires by a liquid injection chemical vapor deposition (CVD) method employing a distorted octahedral [SnCl4{nBuSe(CH2)3SenBu}] single‐source diselenoether precursor is reported. CVD with this single‐source precursor allows morphological and compositional control of the SnSex nanostructures formed, including the transformation of SnSe2 nanoflakes into SnSe nanowires and again to SnSe nanoflakes with increasing growth temperature. Significantly, highly crystalline SnSe nanowires with an orthorhombic Pnma 62 crystal structure can be controllably synthesized in two growth directions, either <011> or <100>. The ability to tune the growth direction of SnSe will have important implications for devices constructed using these nanocrystals. The SnSe nanowires with a <011> growth direction display a reversible polarity‐dependent memory switching ability, not previously reported for nanoscale SnSe. A resistive switching on/off ratio of 103 without the use of a current compliance limit is seen, illustrating the potential use of SnSe nanowires for low‐power nonvolatile memory applications. [ABSTRACT FROM AUTHOR]

Abstract: Identifying cheap, yet effective, oxygen evolution catalysts is critical to the advancement of water splitting. Using liquid exfoliated Co(OH)2 nanosheets as a model system, a simple procedure is developed to maximize the activity of any oxygen evolution reaction nanocatalyst. First the nanosheet edges are confirmed as the active areas by analyzing the catalytic activity as a function of nanosheet size. This allows the authors to select the smallest nanosheets (length ≈50 nm) as the best performing catalysts. While the number of active sites per unit electrode area can be increased via the electrode thickness, this is found to be impossible beyond ≈10 µm due to mechanical instabilities. However, adding carbon nanotubes increases both toughness and conductivity significantly. These enhancements mean that composite electrodes consisting of small Co(OH)2 nanosheets and 10 wt% nanotubes can be made into freestanding films with thickness of up to 120 µm with no apparent electrical limitations. The presence of diffusion limitations results in an optimum electrode thickness of 70 µm, yielding a current density of 50 mA cm−2 at an overpotential of 235 mV, close to the state of the art in the field. Applying this procedure to a high‐performance catalyst such as NiFeOx should significantly surpass the state of the art. [ABSTRACT FROM AUTHOR]

Abstract: This report demonstrates highly efficient nonradiative energy transfer (NRET) from alloyed CdSeS/ZnS semiconductor nanocrystal quantum dots (QDs) to MoS2 films of varying layer thicknesses, including pristine monolayers, mixed monolayer/bilayer, polycrystalline bilayers, and bulk‐like thicknesses, with NRET efficiencies of over 90%. Large‐area MoS2 films are grown on Si/SiO2 substrates by chemical vapor deposition. Despite the ultrahigh NRET efficiencies there is no distinct increase in the MoS2 photoluminescence intensity. However, by studying the optoelectronic properties of the MoS2 devices before and after adding the QD sensitizing layer photocurrent enhancements as large as ≈14‐fold for pristine monolayer devices are observed, with enhancements on the order of ≈2‐fold for MoS2 devices of mixed monolayer and bilayer thicknesses. For the polycrystalline bilayer and bulk‐like MoS2 devices there is almost no increase in the photocurrent after adding the QDs. Industrially scalable techniques are specifically utilized to fabricate the samples studied in this report, demonstrating the viability of this hybrid structure for commercial photodetector or light harvesting applications. [ABSTRACT FROM AUTHOR]

Here we have investigated the influence of the antenna group position on both the formation of chiral amphiphilic EuIII-based self-assemblies in CH3CN solution and, on the ability to form monolayers on the surface of quartz substrates using the Langmuir-Blodgett technique, by changing from the 1-naphthyl ( 2( R), 2( S)) to the 2-naphthyl ( 1( R), 1( S)) position. The evaluation of binding constants of the self- assemblies in CH3CN solution was achieved using conventional techniques such as UV/Visible and luminescence spectroscopies along with more specific circular dichroism (CD) spectroscopy. The binding constants obtained for EuL, EuL2 and EuL3 species in the case of 2-naphthyl derivatives were comparable to those obtained for 1-naphthyl derivatives. The analysis of the changes in the CD spectra of 1( R) and 1( S) upon addition of EuIII not only allowed us to evaluate the values of the binding constants but the resulting recalculated spectra may also be used as fingerprints for assignment of the chiral self-assembly species formed in solution. The obtained monolayers were predominantly formed from EuL3 (≈85 %) with the minor species present in ≈15 % EuL2. [ABSTRACT FROM AUTHOR]

Concentrating solar thermal power plants with thermal energy storage is a potential source of clean electrical power. This work has the same four optimal control modes established in a previous paper where Pontryagin's principle demonstrated that to maximise revenue from a plant with unlimited storage the optimal modes were to: (i) store all collected power, without generating; (ii) generate using collected power only; (iii) generate at maximum capacity using both collected and stored power; (iv) generate a maximum capacity, storing any surplus power. This paper presents an expanded analysis to cover a more realistic case where there is limited storage capacity, introducing 2 differences. First, it is sometimes necessary to discard power if the store is full. Second, the critical prices used to determine the optimal control can change whenever the store becomes full or empty. Again we use Pontragin's principle to derive necessary conditions for an optimal control and present an algorithm to find the sequence of critical prices required to construct it. The analysis gives more insight into the nature of the optimal control than mathematical programming or probabilistic search techniques, and the calculation is fast‐finding the optimal control for a yearlong operation in about 30 seconds. [ABSTRACT FROM AUTHOR]

New electricity generation technologies are often assessed using simple metrics such as average return, break-even energy prices or levelised cost of electricity. These simple metrics do not always capture the full economic value of a technology, particularly those that can react quickly and efficiently to changes in demand. In a wholesale spot market, opportunities exist to capture greater revenues, as currently achieved by peak power plants. This study demonstrates the use of two complementary methods to determine how storage should be operated to maximise revenue. First, the authors formulate and solve the problem as a linear program. The results indicate that there are distinct control modes. They then use Pontryagin's principle to confirm that the optimal operating strategy has three distinct control modes: (i) store all collected power, without generating, (ii) generate using collected power only and (iii) generate at maximum capacity using both collected and stored power. The mode that should be used at any instant depends only on the spot price of electricity relative to a pair of critical prices. These critical prices depend on the total energy that will be collected and the turnaround efficiency of the storage system. [ABSTRACT FROM AUTHOR]

ABSTRACT Rainfall is the key hydroclimatic variable that plays a vital role in the development of regional water management policies. Assessment of observed rainfall behaviour and its spatial and temporal variations are therefore important for climate change adaptation measures. This study assessed trends and step changes in observed annual and seasonal rainfalls across the South Australian region. More than 100 years of high-quality rainfall data from 53 rainfall stations were analyzed using robust statistical techniques. The results are presented according to the eight South Australian natural resource management regions. Increasing annual rainfall trends were observed for the Arid Lands, Alinytjara Wilinara and Adelaide and Mount Lofty Ranges regions whereas decreasing trends were found for the Murray Darling Basin, Eyre Peninsula and South East regions. Both upward and downward trends were identified in the Northern and Yorke region. Seasonally, austral spring and summer rainfalls exhibited increasing trends in most of the regions whereas autumn and winter rainfalls showed decreasing trends. Most of the rainfall step changes were observed to happen in the 1960s and 1970s. The study also includes a discussion on possible mechanisms of South Australian rainfall variability and changes that may have links to the observed trends and step changes. [ABSTRACT FROM AUTHOR]

Herbivores, particularly introduced ones such as sheep and rabbits, have reduced the levels of regeneration of a number of species of native trees and shrubs in the arid rangelands of southern Australia since European settlement. These reduced levels of regeneration mean that populations of some species are declining while others, less palatable to herbivores, are being maintained, hence gradually altering the composition and/or overall cover of vegetation. In the long term, this could result in loss of palatable species valuable to the pastoral industry for animal production, and/or the dominance of large areas by undesirable "woody weed" species. To investigate the effects of grazing, we develop a model which projects the long-term survival rate of a focus species, My- oporum platycarpurn, under grazing and nongrazing regimes. The technique we are applying is an extension of the Leslie growth model, where the vital rates are linked to random rain- fall events and deterministic grazing. The effect of grazing is incorporated into the model based upon data primarily collected from the TGB Osborn Koonarnore Vegetation Reserve, 400 km north of Adelaide in South Australia within and without the exclosure. The results suggest that only with higher than average rainfall for extended periods will the species of interest, M. platycarpurn, survive under grazing. [ABSTRACT FROM AUTHOR]

We prove an extended Granger–Johansen representation theorem (GJRT) for finite‐ or infinite‐order integrated autoregressive time series on Banach space. We assume only that the resolvent of the autoregressive polynomial for the series is analytic on and inside the unit circle except for an isolated singularity at unity. If the singularity is a pole of finite order the time series is integrated of the same order. If the singularity is an essential singularity the time series is integrated of order infinity. When there is no deterministic forcing the value of the series at each time is the sum of an almost surely convergent stochastic trend, a deterministic term depending on the initial conditions and a finite sum of embedded white noise terms in the prior observations. This is the extended GJRT. In each case the original series is the sum of two separate autoregressive time series on complementary subspaces – a singular component which is integrated of the same order as the original series and a regular component which is not integrated. The extended GJRT applies to all integrated autoregressive processes irrespective of the spatial dimension, the number of stochastic trends and cointegrating relations in the system and the order of integration. [ABSTRACT FROM AUTHOR]

BSTRACT: In the current forecasting practice, future water requirements of a growing urban area are often represented as the product of the number of people to be served by the water system and an assumed quantity of gross per capita water use. This paper describes a forecasting approach that differs from the per capita method in two important aspects. First, it disaggregates urban water use into a large number of categories, each consisting of a relatively homogeneous group of water users. Second, it links water use in each category to factors that determine both the need for water as well as the intensity of water use. This approach is incorporated into a computerized forecasting system referred to as IWR-MAIN. The advantages of the IWR.MAIN model over the traditional per capita method are illustrated in a case study of Anaheim, California. [ABSTRACT FROM AUTHOR]

BSTRACT The generation of electric energy in steam-electric power plants is accompanied by the discharge of large quantities of waste heat into the environment. In most cases, this heat is released into natural bodies of water at temperatures relatively close to ambient. In certain locations, such as the Chesapeake Bay, discharges of waste heat may triple in the next decade. It is expected that past practices of thermal discharge, if continued into the future, will result in significant damages to other legitimate users of the water resource, both present and future. This paper reviews the economic causes of these potential damages, and describes the role of public policy as one of removing such causes through regulation incentive or intervention. Possible public policies are reviewed, including prohibition, standards, various types of dollar incentives such as taxes and subsidies, marketable effluent permits, and direct government investment. The innovative power plant siting program recently adopted in Maryland is also discussed. It is concluded that no statements can be made regarding the comparative efficiency or effectiveness of the various policies at the present state of knowledge. It is recommended that policy-makers adopt mixed strategies, preserving as many options as possible for dealing with similar problems in the future. [ABSTRACT FROM AUTHOR]

BSTRACT A system study was conducted on the use of a large number of small reservoirs dispersed throughout an urban community as a means of storm water pollution control. The study was based on an area within the 'new city' of Columbia, Maryland. Water collected and stored in the reservoirs is treated for release or use in meeting sub-potable and potable water demands in the community. Design and performance criteria were developed for such a system. A simulation model and a computerized evaluation technique were used to select the optimal locations and system configurations. The results of this study indicated that such a system would be less expensive than a conventional engineering approach to storm water pollution control. Further, the benefits derived from use of the storm water as a water supply can offset a portion of the cost of pollution control. Several secondary benefits also result from this concept including erosion and sediment control, storm flow dampening, and recreational facilities. A program is now underway to demonstrate this concept in Columbia, Maryland. [ABSTRACT FROM AUTHOR]

Graphene‐based materials are under consideration as a new generation of biomaterials for medical applications, owning to their distinctive physicochemical properties. A major obstacle to clinical translation of novel biomaterials is the presence of residual endotoxin contaminants that can trigger deleterious inflammatory responses and unrelated immunomodulatory effects. To overcome this challenge, a liquid exfoliation methodology to prepare endotoxin‐free bovine serum albumin (BSA)‐exfoliated pristine graphene (EF‐Gr) was developed and compared with conventional BSA‐exfoliated graphene (C‐Gr) and sodium cholate‐exfoliated graphene (SC‐Gr). In contrast to SC‐Gr, protein‐exfoliated graphene exhibits low toxicity. Moreover, BSA‐exfoliated EF‐Gr does not trigger cytokine secretion or increase costimulatory molecule expression in dendritic cells (DCs) or macrophages; however it retains the ability to activate the NLRP3 inflammasome in DCs primed with Toll‐like receptor (TLR) agonists. The results suggest that some reported immunostimulatory effects of graphene preparations may have resulted from contaminants in the formulations. When injected into mice, the inflammatory response induced is comparable in magnitude to that induced by the safe and effective vaccine adjuvant alum. Overall, the study demonstrates the feasibility of producing endotoxin‐free pristine graphene that facilitates assessment of the potential of pristine graphene for novel biomedical applications without the confounding effects of toxic and inflammatory contaminants. This study reports the production of endotoxin‐free bovine serum albumin (BSA)‐exfoliated pristine graphene (EF‐Gr) and its capacity to modulate immune cell responses. While conventional BSA‐exfoliated graphene induces unspecific immunomodulatory responses, the same is not observed with EF‐Gr. This suggests that previously reported effects of graphene preparations might have resulted from contaminants and calls for a reassessment in the literature. [ABSTRACT FROM AUTHOR]

Background: The influence of adhesive skin drapes on abdominal wall compliance during laparoscopy has not previously been studied. Methods: The effect of removing an adhesive abdominal drape on intraperitoneal volume and pressure was studied in 15 patients undergoing a variety of laparoscopic procedures. The internal consistency of this data was evaluated by comparing the observed response to that which was predicted from analysis based on the theory of elasticity. Results: Removal of an adhesive skin drape after induction of a 15-mmHg pneumoperitoneum was associated with changes in intraperitoneal pressure and volume. These changes were statistically significant, highly predictable and clinically relevant. Conclusions: On the basis of the present observations, we recommend that extensive coverage by adhesive drapes should be avoided for those patients or procedures in which elevated intraperitoneal pressure may be particularly deleterious. [ABSTRACT FROM AUTHOR]

For various applications it is necessary to know not only global solar radiation values, but also the diffuse and beam components. Because often only global values are available, there have been several models developed to establish correlations between the diffuse fraction and various predictors. These typically include the clearness index, but also may include the solar angle, temperature and humidity. The clearness index is the proportion of extraterrestrial radiation reaching a location, where the extraterrestrial value used in the calculation varies with latitude and time of year. These correlations have been developed using data principally from latitudes greater than 40 deg. , often using only data from a few locations and with few exceptions have not used solar altitude as a predictor. Generally the data consist of hourly integrated values. A model has been developed using hourly data from a weather station set up at Deakin University, Geelong. Another model has also been developed for 15 minute data values in order to ascertain if the smoothing generated by using hourly data makes a significant difference to overall results. The construction of such models has been investigated, enabling an extension to the research, inclusive of other stations, to be performed systematically. A final investigation was carried out, using data from other Australian locations, to explain some of the considerable scatter by adding apparent solar time as a predictor, which proved to be significantly better than solar altitude. [ABSTRACT FROM AUTHOR]

Seagrass plays a major role in supporting the processes and functionof the marine environment and is a key fisheries habitat, which provides nursery, feeding and breeding areas for fish and crustaceans. Seagrass beds also stabilise the seabed, trap sediments, reduce coastalerosion and provide the basis for the food chain through photosynthesis. The goal of this project is to establish a seagrass-fish habitatspatial model that will quantitatively assess the economic value of seagrass habitats, particularly for fisheries production and this paper describes a preliminary step in the model construction. With the help of fisheries scientists from the South Australian Research and Development Institute (SARDI), the functional relationship of some economically important species of fish, crustaceans and molluscs to seagrass habitats was investigated. As a result, a seagrass residency index (SRI) fior some species has been estimated indicating the species most likely to be affected by changes in health and abundance of the seagrass beds in the coastal waters of South Australia. The information collected mainly relates to the periods of time spent amongst seagrass beds, sheltered reefs and open waters at different life stages ofthe fish: larval/juvenile, adult/feeding and adult/spawning. It was then hypothesized that the SRI would be a weighted sum of the averages of the estimated residence time at each stage. This paper describeshow the SRI figures were calculated and outlines the intended use ofthe indices, in conjunction with other information, to assess the value of seagrass habitats. [ABSTRACT FROM AUTHOR]