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The See Change survey was designed to make z > 1 cosmological measurements by efficiently discovering high-redshift Type Ia supernovae (SNe Ia) and improving cluster mass measurements through weak lensing. This survey observed twelve galaxy clusters with the Hubble Space Telescope (HST) spanning the redshift range z = 1.13–1.75, discovering 57 likely transients and 27 likely SNe Ia at z ∼ 0.8–2.3. As in similar previous surveys, this proved to be a highly efficient use of HST for supernova observations; the See Change survey additionally tested the feasibility of maintaining, or further increasing, the efficiency at yet higher redshifts, where we have less detailed information on the expected cluster masses and star formation rates. We find that the resulting number of SNe Ia per orbit is a factor of ∼8 higher than for a field search, and 45% of our orbits contained an active SN Ia within 22 rest-frame days of peak, with one of the clusters by itself yielding 6 of the SNe Ia. We present the survey design, pipeline, and supernova discoveries. Novel features include fully blinded supernova searches, the first random forest candidate classifier for undersampled IR data (with a 50% detection threshold within 0.05 mag of human searchers), real-time forward-modeling photometry of candidates, and semi-automated photometric classifications and follow-up forecasts. We also describe the spectroscopic follow-up, instrumental in measuring host galaxy redshifts. The cosmology analysis of our sample will be presented in a companion paper. [ABSTRACT FROM AUTHOR]

Graphical abstract Highlights • A parallel thermographic screen allows measurement of particle size and support effects on model planar catalysts. • The turn over frequency (TOF) of an exothermic reaction can be determined simultaneously on 100 catalysts. • The catalytic activity for CO oxidation of titania supported gold with particle sizes 6 > d/nm > 1.5 has been measured. • A monotonic increase in the TOF is observed with decreasing particle diameter (d) which is proportional to ca. d−1.8. • Calculation of the gold surface area evidences a surface specific activity of the gold which increases as ca. d−4. • The steep rise in activity suggests an electronic perturbation of the gold nano-particles by the substrate. Abstract A parallel thermographic screening methodology has been developed which allows the measurements of the particle size and support influences on model planar heterogeneous catalysts. A screening chip was designed and fabricated in order to produce multiple fields of low stress silicon nitride membranes that exhibit low thermal conductivity and heat capacity. The heat generated on supported model catalysts in an exothermic reaction on the membranes was measured using a thermal (infra-red) imaging camera, which in turn provided a measure of the turn over frequency (TOF) for the reaction. The catalytic activity for CO oxidation on titania supported gold model catalysts with varying particle size has been measured on 100 catalysts simultaneously. The reaction has been investigated at 80 °C and 170 °C, and pressures ranging between 0.06 mbar and 1.5 mbar for various O 2 :CO ratios. Under all conditions investigated, a monotonic increase in the TOF is observed with decreasing particle diameter (d) which is proportional to ca. d−1.8 in the range 6 > d/nm > 1.5. This is in the opposite direction to the number of potentially active perimeter sites which increases linearly with increasing particle size on these catalysts. We show that the surface area specific activity of the gold is increasing even more steeply with reduced particle size, and is proportional to ca. d−4. This rate of increase in activity is significantly higher than one would expect by any increase one may expect as a result of more active low co-ordinate sites on the gold. The steep increase in activity is ascribed to an electronic interaction between the substrate and the particle. [ABSTRACT FROM AUTHOR]

Climate change and species invasions represent key threats to global biodiversity. Subarctic freshwaters are sentinels for understanding both stressors because the effects of climate change are disproportionately strong at high latitudes and invasion of temperate species is prevalent. Here, we summarize the environmental effects of climate change and illustrate the ecological responses of freshwater fishes to these effects, spanning individual, population, community and ecosystem levels. Climate change is modifying hydrological cycles across atmospheric, terrestrial and aquatic components of subarctic ecosystems, causing increases in ambient water temperature and nutrient availability. These changes affect the individual behavior, habitat use, growth and metabolism, alter population spawning and recruitment dynamics, leading to changes in species abundance and distribution, modify food web structure, trophic interactions and energy flow within communities and change the sources, quantity and quality of energy and nutrients in ecosystems. Increases in temperature and its variability in aquatic environments underpin many ecological responses; however, altered hydrological regimes, increasing nutrient inputs and shortened ice cover are also important drivers of climate change effects and likely contribute to context-dependent responses. Species invasions are a complex aspect of the ecology of climate change because the phenomena of invasion are both an effect and a driver of the ecological consequences of climate change. Using subarctic freshwaters as an example, we illustrate how climate change can alter three distinct aspects of species invasions: (1) the vulnerability of ecosystems to be invaded, (2) the potential for species to spread and invade new habitats, and (3) the subsequent ecological effects of invaders. We identify three fundamental knowledge gaps focused on the need to determine (1) how environmental and landscape characteristics influence the ecological impact of climate change, (2) the separate and combined effects of climate and non-native invading species and (3) the underlying ecological processes or mechanisms responsible for changes in patterns of biodiversity. [ABSTRACT FROM AUTHOR]

Background: Fish fin is a widely used, non-lethal sample material in studies using stable isotopes to assess the ecology of fishes. However, fish fin is composed of two distinct tissues (ray and membrane) which may have different stable isotope values and are not homogeneously distributed within a fin. As such, estimates of the stable isotope values of a fish may vary according to the section of fin sampled. Methods: To assess the magnitude of this variation, we analysed carbon (δ13C), nitrogen (δ15N), hydrogen (δ2H) and oxygen (δ18O) stable isotopes of caudal fin from juvenile, riverine stages of Atlantic salmon (Salmo salar) and brown trout (Salmo trutta). Individual fins were sub-sectioned into tip, mid and base, of which a further subset were divided into ray and membrane. Findings: Isotope variation between fin sections, evident in all four elements, was primarily related to differences between ray and membrane. Base sections were13C depleted relative to tip (~ 1 ‰) with equivalent variation evident between ray and membrane. A similar trend was evident in δ2H, though the degree of variation was far greater (~ 10 ‰). Base and ray sections were 18O enriched (~ 2 ‰) relative to tip and membrane, respectively. Ray and membrane sections displayed longitudinal variation in 15N mirroring that of composite fin (~ 1 ‰), indicating that variation in15N values was likely related to ontogenetic variation. Conclusions: To account for the effects of intra-fin variability in stable isotope analyses we suggest that researchers sampling fish fin, in increasing priority, 1) also analyse muscle (or liver) tissue from a subsample of fish to calibrate their data, or 2) standardize sampling by selecting tissue only from the extreme tip of a fin, or 3) homogenize fins prior to analysis. [ABSTRACT FROM AUTHOR]

Oldowan lithic assemblages are often portrayed as a product of the need to obtain sharp flakes for cutting into animal car cases. However, ethnographic and experimental research indicates that the optimal way to produce flakes for such butchering purposes is via bipolar reduction of small cryptocrystalline pebbles rather than from larger crystalline cores resembling choppers. Ethnographic observations of stone tool-using hunter-gatherers in environments comparable with early hominins indicate that most stone tools (particularly chopper forms and flake tools) were used for making simple shaft tools including spears, digging sticks and throwing sticks. These tools bear strong resemblances to Oldowan stone tools. Bipolar reduction for butchering probably preceded chopper-like core reduction and provides a key link between primate nut-cracking technologies and the emergence of more sophisticated lithic technologies leading to the Oldowan. [ABSTRACT FROM AUTHOR]

Climate change is increasing ambient temperatures in Arctic and subarctic regions, facilitating latitudinal range expansions of freshwater fishes adapted to warmer water temperatures. The relative roles of resource availability and interspecific interactions between resident and invading species in determining the outcomes of such expansions has not been adequately evaluated. Ecological interactions between a cool-water adapted fish, the perch (Perca fluviatilis), and the cold-water adapted European whitefish (Coregonus lavaretus), were studied in both shallow and deep lakes with fish communities dominated by (1) monomorphic whitefish, (2) monomorphic whitefish and perch, and (3) polymorphic whitefish and perch. A combination of stomach content, stable-isotope, and invertebrate prey availability data were used to identify resource use and niche overlap among perch, the trophic generalist large sparsely rakered (LSR) whitefish morph, and the pelagic specialist densely rakered (DR) whitefish morph in 10 subarctic lakes at the contemporary distribution limit of perch in northern Scandinavia. Perch utilized its putative preferred littoral niche in all lakes. LSR whitefish utilized both littoral and pelagic resources in monomorphic whitefish-dominated lakes. When found in sympatry with perch, LSR whitefish exclusively utilized pelagic prey in deep lakes, but displayed niche overlap with perch in shallow littoral lakes. DR whitefish was a specialist zooplanktivore, relegating LSR whitefish from pelagic habitats, leading to an increase in niche overlap between LSR whitefish and perch in deep lakes. Our results highlight how resource availability (lake depth and fish community) governs ecological interactions between native and invading species, leading to different outcomes even at the same latitudes. These findings suggest that lake morphometry and fish community structure data should be included in bioclimate envelope-based models of species distribution shifts following predicted climate change. [ABSTRACT FROM AUTHOR]

It has long been speculated that increasing demands for cereals for the purposes of brewing beer led to domestication in the Near Eastern Natufian cultures. While the question of whether cereals were being used in beer production is an important issue, it has remained a difficult proposition to test. We present some new perspectives on traditional brewing techniques relevant to this issue, on archaeological remains, and on the paleoecology of the Near East. Taken together, these observations provide more compelling circumstantial evidence that makes it increasingly likely that brewing of beer was an important aspect of feasting and society in the Late Epipaleolithic. [ABSTRACT FROM AUTHOR]

The article focuses on the recovery of remains of traditional corporate group residences by archaeologists in Southeast Asia. The article discusses the use of long houses as shared domestic spaces, the practice of communal feasting and communities in which this living style is common including the Ta Oi, Monong Gar and Rhadé. The article goes on to discuss the effect of industrialism on these communities and the way in which some policies could be considered "cultural genocide."

Abstract: Most high throughput studies focus on assessing the effect of composition within a single known fundamental structure type, such as perovskite. Here we demonstrate how high throughput synthesis and screening can be used to establish structure–property relations in the PbO–Nb2O5 system, for which eight distinct fundamental structure types are known to exist. PbNb4O11, PbNb2O6 and pyrochlore could be easily distinguished by X-ray diffraction (XRD). However, XRD was insensitive to distortions of the pyrochlore structure and instead Raman spectroscopy was utilized to determine changes in symmetry from cubic to rhombohedral as the PbO concentration increased. High throughput screening of the capacitance revealed permittivity (εr ) maxima in the PbNb4O11 (εr =700) and cubic pyrochlore phases (εr =450). The εr of PbNb4O11 has not to date been reported but the value for cubic pyrochlore is higher than that reported for bulk ceramics (εr =270). Initial high electric field studies also revealed exceptionally high tunability (four times that reported for bismuth zinc niobate-based pyrochlores) of the capacitance in the pyrochlore phase. [Copyright &y& Elsevier]

Background: The potential role hybridisation in adaptive radiation and the evolution of new lineages has received much recent attention. Hybridisation between roach (Rutilus rutilus L.) and bream (Abramis brama L.) is well documented throughout Europe, however hybrids in Ireland occur at an unprecedented frequency, often exceeding that of both parental species. Utilising an integrated approach, which incorporates geometric morphometrics, life history and molecular genetic analyses we identify the levels and processes of hybridisation present, while also determining the direction of hybridisation, through the analysis of mitochondrial DNA. Results: The presence of F2 hybrids was found to be unlikely from the studied populations, although significant levels of backcrossing, involving both parental taxa was observed in some lakes. Hybridisation represents a viable conduit for introgression of genes between roach and bream. The vast majority of hybrids in all populations studied exhibited bream mitochondrial DNA, indicating that bream are maternal in the majority of crosses. Conclusions: The success of roach × bream hybrids in Ireland is not due to a successful self reproducing lineage. The potential causes of widespread hybridisation between both species, along with the considerations regarding the role of hybridisation in evolution and conservation, are also discussed. [ABSTRACT FROM AUTHOR]

In a series of publications, Prentiss et al. (2003, 2005, 2007, 2008) have argued for a very late, abrupt, and brief emergence of large villages and large corporate residences in the mid-Fraser region of British Columbia (~1600-800 cal B.P.) and an even later abrupt emergence of socioeconomic complexity (~1200-800 cal B.P.). They postulate that climatic changes were responsible for both of these events as well as the collapse of the large villages. We question their interpretations on several grounds including: inappropriate methods for dating these developments; data from Keatley Creek indicating a longer developmental trajectory; incomplete interpretation of paleoclimate trends for the region; and internal contradictions in their own climate-driven explanations for changes. The combined evidence of geochronology and paleoecology (some not previously considered) together with archaeological evidence favors an interpretation of earlier emergence of large villages and socioeconomic complexity than suggested by Prentiss et al. (2003, 2005, 2007, 2008). [ABSTRACT FROM AUTHOR]

Feasting has been proposed as the major context and impetus behind the intensification of production leading to the domestication of plants and animals. This article examines the way feasting contributes to fitness in traditional societies through the reduction of risks involving subsistence, reproduction, and violent confrontations. As other authors have noted, the risk-reduction strategies used by simple foragers differ significantly from risk-reduction strategies used by transegalitarian hunter-gatherers and horticulturalists. These differences are examined in more detail and are related to the emergence of feasting in transegalitarian societies. Surplus-based feasting is proposed as an entirely new element in community dynamics, probably first developed during the Upper Paleolithic in Europe, but becoming much more widespread in the world with the development of Mesolithic technology. Because feasting entails survival and risk-reduction benefits, it creates inherently inflationary food- production forces. These elements first appear among complex hunter-gatherers and logically lead to the intensification of food production, ultimately resulting in the domestication of plants and animals. [ABSTRACT FROM AUTHOR]

Abstract: The surface redox behaviour, the stability, and the electro-oxidation of CO on model platinum–tin surface alloy catalysts has been studied by ex situ electrochemical measurements. The Pt(111)–Sn(2×2) and Pt(111)–Sn(√3×√3)R30° surfaces have been prepared and characterised in UHV by vapour deposition of Sn on Pt(111) and the surfaces subsequently transferred for electrochemical investigation. A surface redox couple, which is associated with the adsorption/desorption of hydroxide on the Sn sites, is observed at 0.28VRHE/0.15VRHE in H2SO4 electrolyte on both surfaces. Evidence that it is associated with the adsorption of OH comes from ex situ photoemission measurements, which indicate that the Sn atoms are in a metallic state at potentials below 0.15VRHE, and an oxidised state at potentials above 0.28RHE. Specific adsorption of sulphate anions is not associated with the surface process since there is no evidence from photoemission of sulphate adsorption, and the same surface couple is observed in HClO4 electrolyte. A second surface redox couple, associated with further oxidation of the Sn sites in the alloy surfaces, is observed at 0.8VRHE/0.58VRHE. CO is adsorbed from solution at 300K, with saturation coverages of 0.37±0.05ML and 0.2±0.05ML, respectively. The adsorbed CO is oxidatively stripped at the potential coincident with the adsorption of hydroxide on the tin sites at the lower potential of 0.28VRHE. This strong promotional effect is unambiguously associated with the bi-functional mechanism. The Sn induced activation of water, and promotion of CO electro-oxidation, is sustained as long as the alloy structure remains intact, in the potential range below 0.5VRHE. The instability of the alloy surface at higher potentials is associated with the second redox couple. The redox behaviour at higher potentials is modified by the presence of CO in stripping experiments, with couples now observed at 0.78VRHE/0.56VRHE, and 0.9VRHE/0.70VRHE. This behaviour may be associated with enhanced oxidation through the exclusion of sulphate anions at the surface by CO. [Copyright &y& Elsevier]

Prentiss et al. (2003) have argued for a relatively recent, short (1600-1100 B.P.), and noncontinuous occupation of large villages and large housepits on the British Columbian Plateau. They argue that these developments resulted from climatically induced resource impoverishment in the region. I maintain that their database is inadequate for such conclusions and that their interpretations are in conflict with dates that 1 obtained from large housepits as well as with the distribution of early point styles (dating from 1200-4800 B.P.) that concentrate in the rim middens of large and medium-sized housepits. These data indicate that large villages and housepits that emerged by 2600 B.P., or earlier, were continuously occupied and corresponded more to the development of collector-based technologies rather than any climatic deteriorations or the introduction of the bow and arrow. [ABSTRACT FROM AUTHOR]

Several unusual wood and plant artifactual remains were recovered from the Keatley Creek site in the Interior of British Columbia. The most important of these is a charred fragment of a coiled basket recovered from a Protohistoric Period ritual structure dated to 250 BP. This is the only archaeological example of coiled basketry from the Interior, and such examples are extremely rare on the Coast also. While it may have served as a cooking or water container, we also suggest that it may have been a prestige item, possibly used in ritual contexts. The other artifacts described include a section of a wooden shaft implement like a bow or hoop frame dated to 1410 BP, and a bifacial stone knife from a storage pit that still retained a bark wrapping probably dating to ca. 1000 BP. [ABSTRACT FROM AUTHOR]

There are important reasons for considering the first domesticated plants and animals as luxury foods primarily used in feasting. Using Southeast Asian tribal society as a case study, it is demonstrated that all the domesticated animals and the most important of the domesticated plants constitute forms of wealth that are primarily or exclusively used in feasting contexts. In addition, numerous studies have demonstrated that feasting generates powerful forces that intensify and increase resource production of luxury foods as well as staples. Such forces ultimately can lead to the domestication of wild species and the transformation of luxury foods into staple foods. [ABSTRACT FROM AUTHOR]

Responds to comments on a study related to the abandonment of large housepit villages in the Mid-Fraser River ca. 1200 B.P. Criticisms on the lake formation and migration behavior expectations; Reasons for the abandonment of the Mid-Fraser villages; Claims of Kuijt on the population.

The article presents the author's comments on the article "Cheating at Musical Chairs: Territoriality and Sedentism in an Evolutionary Context," by Michael Rosenberg. Rogenberg's article was focused on population pressure models in prehistoric societies. The author views that population pressures have acted as agents of sociopolitical progress and development. He finds population pressure model ineffective in cases of prehistoric sedentary populations.

Archaeological models and conceptual frameworks have been relatively successful in explaining the emergence of distinctively human types of behavior This perspective can also be used to explain the development of the human species' religious nature and its penchant for ecstatic ritual experiences. Using an archaeological perspective, it is argued that the formation of inter-band alliances were critical for survival in times of severe resource stress In turn, these alliances depended for their effectiveness on the establishment of very strong emotional bonds between members in different bands. Ecstatic states induced by ritualized procedures and shared by members of different bands are proposed as one of the key mechanisms by which strong emotional bonds were created and maintained between bands. Ecstatic states involve the subsuming of individual identities and priorities under unifying concepts, thus enabling bands to overcome natural tendencies to exclusivity in times of stress Moreover, this reliance on ecstatic states leads directly to transcendent concepts typical of all religions Ecstatic religion is therefore viewed as the essential core of early human religious experience and as having become widespread and enduring because it significantly enhanced chances of survival during periods of severe resource stress by maintaining alliance connections. In summary, I suggest that the distinctive emotional makeup that characterizes human beings can largely be explained in terms of the early evolutionary stresses on hunter/gatherers. Early humans required a means to deal with long-term periodic resource shortages just as much as they required a means to deal with daily problems of survival on the open savanna. For short term survival, they developed tools, hunting skills, cooperative sharing, a sexual division of labor, and similar innovations in behavior. To cope with long term crises, they developed alliance systems that enabled them to move out of... [ABSTRACT FROM AUTHOR]

Research at the Keatley Creek site near the Fraser River has provided critical new insights into prehistoric social and economic organization on the Canadian Northwest Plateau. Using a wide range of lithic, faunal, botanical, and chemical analyses, it has been possible to demonstrate that large residential corporate groups exercised privileged access to the best fishing locations and apparently had rights to different mountain regions. These corporate groups maintained these rights as well as their ownership over house locations and specific identities for over a millennium. Large corporate groups were also divided internally into privileged domestic groups and non-privileged domestic groups, probably reflecting hereditary title-holding families and commoners or even slaves. I argue that in order to derive useful information about past social and economic organization, appropriate concepts and questions must be developed from an explicitly archaeological viewpoint rather than a cultural anthropological or sociological perspective. [ABSTRACT FROM AUTHOR]

Analyzes the interaction spheres of the Plateau culture of North America. Effects of the development of elite class in interaction spheres; Reasons for the similarities among Plateau groups; Usage of carved bone drinking tubes by adolescent girls; Plateau ideology.

Highlights inferences about the socioeconomic organization from circa 2400 to 1100 B.P., derived from observing distinct types of cherts and chalcedonies at a prehistoric Keatley Creek site near Lillooet, British Columbia. Analyses from the excavation program at the site; Differences between lithic assemblages of housepits; Residential corporate groups.

The article discusses the contribution of John Knight the recent contribution on hunting pairs has raised important issues and open up a cognitive New Age reverie. It mentions that South Africa eland plays an important role in a theocratic form in contrast to the master of animals. It also notes on the ethnographic work which focuses on traditional community members subscribe to notions.

A letter to the editor is presented in response to an article related to early Neolithic symbolism in the Near East, by Ian Hodder and Lynn Meskell.

Comments on Natalie Munro's paper on Levantine Natufian subsistence and domestication. Munro's equation of hunting pressure with food or resource pressure; Little basis for maintaining that human populations in the core area declined in Late Natufian; Factors indicating that the Natufians were complex hunter-gatherers who engaged in substantial feasting and ritual; Assumptions about ritual food.

The formation of the stellar mass within galaxy cluster cores is a poorly understood process. It features the complicated physics of cooling flows, active galactic nucleus feedback, star formation, and more. Here we study the growth of the stellar mass in the vicinity of the brightest cluster galaxy (BCG) in a z = 1.7 cluster, SpARCS1049+56. We synthesize a reanalysis of existing Hubble Space Telescope imaging, a previously published measurement of the star formation rate, and the results of new radio molecular gas spectroscopy. These analyses represent the past, present, and future star formation, respectively, within this system. We show that a large amount of stellar massâ€"between (2.2 ± 0.5) Ă— 1010 M ⊙ and (6.6 ± 1.2) Ă— 1010 M ⊙ depending on the data processingâ€"exists in a long and clumpy tail-like structure that lies roughly 12 kpc off the BCG. Spatially coincident with this stellar mass is a similarly massive reservoir ((1.0 ± 0.7) Ă— 1011 M ⊙) of molecular gas that we suggest is the fuel for the immense star formation rate of 860 ± 130 M ⊙ yrâˆ'1, as measured by infrared observations. Hlavacek-Larrondo et al. surmised that massive, runaway cooling of the hot intracluster X-ray gas was feeding this star formation, a process that had not been observed before at high redshift. We conclude, based on the amount of fuel and current stars, that this event may be rare in the lifetime of a cluster, producing roughly 15%â€"21% of the intracluster light mass in one go, though perhaps a common event for all galaxy clusters. [ABSTRACT FROM AUTHOR]

Throughout the European Union, the EC Habitats Directive requires that member states undertake national surveillance of designated species. Despite biological connections between-populations across-borders, national assessments need not be co-ordinated in any way. We conducted a trans-boundary assessment of the status of Eurasian otters (Lutra lutra) aimed at providing consistency across a single biogeographical unit, i.e. the island of Ireland, comprising two states, i.e. the Republic of Ireland and the United Kingdom (Northern Ireland). Our aim was to ensure consistency with previous assessments conducted separately in each state, and permit each Government to fulfil their separate statutory reporting commitments. The species range increased by 23% from 1996-2006 and 2007-11. The population estimate of 9400 [95%CI 8700-12,200] breeding females during 2010/11 was not significantly different from 8300 [95%CI 7600-9800] breeding females established as a baseline during 1981-82. Modelling of species-habitat associations suggested that available habitat was not limiting and no putative pressures recorded at sites surveyed negatively affected species occurrence. Thus, under the statutory parameters for assessing a species' conservation status, i.e. range, population, habitat and future prospects, the otter was judged to be in 'Favourable' status throughout Ireland and in both discrete political jurisdictions. Thus, we provide a trans-boundary test case for EU member states that share habitats and species across ecoregions, ensuring conservation assessment data are standardised, synchronised, spatially consistent and, therefore, biologically relevant without compromising legal and administrative autonomy within separate jurisdictions. [ABSTRACT FROM AUTHOR]

Highlights: [•] A high-throughput methodology is used to synthesise and screen PdCu alloys. [•] The expected equilibrium phases of the PdCu alloys were identified using XRD. [•] Pd in Cu results in reversible surface oxidation of Cu and oxide destabilisation. [•] This is a result of bi-functional and electronic effects of Pd in Cu, respectively. [•] The most active catalyst is in a narrow compositional region around 84%at. Cu. [ABSTRACT FROM AUTHOR]

Winter conditions impose dramatic constraints on temperate, boreal, and polar ecosystems, and shape the abiotic and biotic interactions underpinning these systems. At high latitudes, winter can last longer than the growing season and may have a disproportionately large impact on organisms and ecosystems. Even so, our understanding of the ecological implications of winter is often lacking. Indeed, even what exactly defines winter is currently unclear, and boundaries that delineate this season are blurred across marine, freshwater, and terrestrial realms and fields of biology. Here, we discuss the complexity of defining winter, and highlight the importance of maintaining the capacity to test hypotheses across seasons, realms, and domains of life. We then outline questions drawn from diverse fields of research that address current gaps in our understanding of winter ecology and how winter influences multiple levels of biological organization, from individuals to ecosystems. Finally, we highlight the potential consequences of changes to both the length and severity of winter due to climate change, and discuss the role winter may play in mediating ecosystem function in the future. [ABSTRACT FROM AUTHOR]

Abstract: The Eurasian otter (Lutra lutra L.) is a top predator in aquatic systems and plays an important role in ecosystem functioning. However, it has undergone dramatic declines throughout Europe as a result of environmental degradation. We examine the putative role of the otter as a bioindicator in Ireland which remains a stronghold for the species and affords a unique opportunity to examine variation in its ecological niche. We describe diet, using spraint contents, along rivers during 2010 and conduct a review and quantitative meta-analysis of the results of a further 21 studies. We aimed to assess variation in otter diet in relation to river productivity, a proxy for natural nutrification and anthropogenic eutrophication, and availability of salmonid prey (Salmo trutta and Salmo salar), to test the hypothesis that otter diet is related to environmental quality. Otter diet did not vary with levels of productivity or availability of salmonids whilst Compositional Analysis suggested there was no selection of salmonid over non-salmonid fish. There was a distinct niche separation between riverine and lacustrine systems, the latter being dominated by Atlantic eel (Anguilla anguilla). Otters are opportunistic and may take insects, freshwater mussels, birds, mammals and even fruit. Otters living along coasts have a greatest niche breath than those in freshwater systems which encompasses a wide variety of intertidal prey though pelagic fish are rarely taken. It is concluded that the ability of the otter to feed on a wide diversity of prey taxa and the strong influence of habitat type, renders it a poor bioindicator of environmental water quality. It seems likely that the plasticity of the habitat and dietary niche of otters, and the extent of suitable habitat, may have sustained populations in Ireland despite intensification of agriculture during the 20th century. [Copyright &y& Elsevier]

Electrodeposited rhodium films on titanium substrates have been electrochemically activated to produce a high area surface with a specific activity for nitrate electroreduction directly to N2. The activation process involves oxidation/ reduction cycles in an alkaline, KCI electrolyte containing nitrate ions. Surfaces of up to 230 times the geometric area are achieved, together with a surface morphological modification. While the active surface, once formed, is intrinsically unstable during long-term nitrate reduction, its activity can be maintained in situ by an electrochemical cycling procedure. The high area rhodium has the form of a nano-structured 'sponge', with a surface area of ca. 19 m² g-1. The morphological modification is evidenced by a change in the hydrogen UPD structure, changes in the surface redox behaviour associated with OH adsorption, and a reduction in the activation energy for nitrate reduction from ca. 47 to 20 kJ mol-1. The reduction in activation energy, however, is accompanied by a decrease in the pre-exponential factor, and this apparent compensation effect results in similar rate constants on the activated and unactivated surfaces. The enhancement in the catalyst's activity for nitrate reduction results from an increase in the relative activity of nitrate reduction over water reduction. The activated catalyst sustains steady state nitrate reduction at an increased over-potential before the reaction to N2 decays, and hydrogen evolution and reduction to ammonia take place. The presence of nitrate ions is essential for the formation of the active surface, and specifically adsorbed nitrate ions and reductive intermediates are present at the surface when it is reformed. A mechanism for the elementary surface reaction steps involved in nitrate reduction, and the apparent 'habit' growth of the active surface phase in the nitrate containing solution is discussed. [ABSTRACT FROM AUTHOR]

Phenotypic plasticity can be expressed as changes in body shape in response to environmental variability. Crucian carp (Carassius carassius), a widespread cyprinid, displays remarkable plasticity in body morphology and increases body depth when exposed to cues from predators, suggesting the triggering of an antipredator defense mechanism. However, these morphological changes could also be related to resource use and foraging behavior, as an indirect effect of predator presence. In order to determine whether phenotypic plasticity in crucian carp is driven by a direct or indirect response to predation threat, we compared twelve fish communities inhabiting small lakes in southeast Norway grouped by four categories of predation regimes: no predator fish, or brown trout (Salmo trutta), perch (Perca fluviatilis), or pike (Esox lucius) as main piscivores. We predicted the body shape of crucian carp to be associated with the species composition of predator communities and that the presence of efficient piscivores would result in a deeper body shape. We use stable isotope analyses to test whether this variation in body shape was related to a shift in individual resource use—that is, littoral rather than pelagic resource use would favor the development of a specific body shape—or other environmental characteristics. The results showed that increasingly efficient predator communities induced progressively deeper body shape, larger body size, and lower population densities. Predator maximum gape size and individual trophic position were the best variables explaining crucian carp variation in body depth among predation categories, while littoral resource use did not have a clear effect. The gradient in predation pressure also corresponded to a shift in lake productivity. These results indicate that crucian carp have a fine‐tuned morphological defense mechanism against predation risk, triggered by the combined effect of predator presence and resource availability. [ABSTRACT FROM AUTHOR]

We calculate H α-based star formation rates and determine the star formation rate–stellar mass relation for members of three Spitzer Adaptation of the Red-Sequence Cluster Survey (SpARCS) clusters at z ∼ 1.6 and serendipitously identified field galaxies at similar redshifts to the clusters. We find similar star formation rates in cluster and field galaxies throughout our range of stellar masses. The results are comparable to those seen in other clusters at similar redshifts, and consistent with our previous photometric evidence for little quenching activity in clusters. One possible explanation for our results is that galaxies in our z ∼ 1.6 clusters have been accreted too recently to show signs of environmental quenching. It is also possible that the clusters are not yet dynamically mature enough to produce important environmental quenching effects shown to be important at low redshift, such as ram-pressure stripping or harassment. [ABSTRACT FROM AUTHOR]

The morphology–density relationship states that dense cosmic environments such as galaxy clusters have an overabundance of quiescent elliptical galaxies, but it is unclear at which redshift this relationship is first established. We study the morphology of four clusters with 1.2 < z < 1.8 using Hubble Space Telescope imaging and the morphology computation code statmorph. By comparing the median morphology of cluster galaxies to CANDELS field galaxies using Monte Carlo analysis, we find that two out of four clusters (at z = 1.19 and 1.75) have an established morphology–density relationship with more than 3σ significance. Approximately 50% of the galaxies in these clusters are bulge-dominated, compared to ∼30% in the field, and they are significantly more compact. This result is more significant for low-mass galaxies with , showing that low-mass galaxies are affected the most in clusters. We also find an intriguing system of two z ≈ 1.45 clusters at a unusually small 2D separation of 3′ and 3D separation of ≈73 Mpc that exhibit no morphology–density relationship but have enhanced merger signatures. We conclude that the environmental mechanism responsible for the morphology–density relationship is (1) already active as early as z = 1.75; (2) forms compact, bulge-dominated galaxies; and (3) affects primarily low-mass galaxies. However, there is a significant degree of intracluster variance that may depend on the larger cosmological environment in which the cluster is embedded. [ABSTRACT FROM AUTHOR]

Memory structures play a basic role in providing integrated circuits of powerful processing capabilities. Even most powerful processors have nothing to offer without an accompanying memory and importantly, the development of mobile devices is dependent on the continual improvement of memory technology. Herein, we report the synthesis of TiO 2 thin films on SSTOP (Pt/TiO 2 /SiO 2 /Si) substrate via physical vapour deposition process for the first time. The layers consisted of Si, SiO 2 , TiO 2 and Pt, hence the SSTOP shorthand is used throughout the text. Three different phases of TiO 2 thin films were obtained, i.e. amorphous, anatase and rutile phases, by controlling the reaction parameters which were examined by x-ray diffraction (XRD), scanning electron microscopy (SEM), energy dispersive spectroscopy (EDS), atomic force microscopy (AFM) and Raman-scattering spectroscopy in order to understand the crystallographic, morphological, compositional and scattering properties. The detailed studies confirmed the formation of various crystal phases of titania. The grown thin films on SSTOP substrates were further utilized to fabricate resistive random access memory (ReRAM) devices and the initial electrical screening was performed on capacitor-like structures which were prepared using platinum top electrodes (diameter = 250 μm) on a 14 × 14 array metal contact mask. Current-Voltage (I–V) measurements were implemented employing a range of current compliances (IC). The detailed electrical characterizations revealed that the forming field for a switchable unipolar device was found to be greatest on rutile titania and lowest on the amorphous titania phase. Similarity, the resistive contrast was greatest on the rutile titania phase and lowest on the anatase titania phase. Design for ReRAM device based on Pt/TiO 2 /SiO 2 /Si (SSTOP) substrate. Image 1 [ABSTRACT FROM AUTHOR]

We constrain the evolution of the brightest cluster galaxy plus intracluster light (BCG + ICL) using an ensemble of 42 galaxy groups and clusters that span redshifts of z  = 0.05−1.75 and masses of M500, c = 2 × 1013−1015 M⊙. Specifically, we measure the relationship between the BCG + ICL stellar mass M⋆ and M500, c at projected radii 10 < r < 100 kpc for three different epochs. At intermediate redshift (⁠|$\bar{z}=0.40$|⁠), where we have the best data, we find M⋆ ∝ M500, c 0.48 ± 0.06. Fixing the exponent of this power law for all redshifts, we constrain the normalization of this relation to be 2.08 ± 0.21 times higher at |$\bar{z}=0.40$| than at high redshift (⁠|$\bar{z}=1.55$|⁠). We find no change in the relation from intermediate to low redshift (⁠|$\bar{z}=0.10$|⁠). In other words, for fixed M500, c , M⋆ at 10 < r < 100 kpc increases from |$\bar{z}=1.55$| to |$\bar{z}=0.40$| and not significantly thereafter. Theoretical models predict that the physical mass growth of the cluster from z  = 1.5 to z  = 0 within r500, c is 1.4×, excluding evolution due to definition of r500, c . We find that M⋆ within the central 100 kpc increases by ∼3.8× over the same period. Thus, the growth of M⋆ in this central region is more than a factor of 2 greater than the physical mass growth of the cluster as a whole. Furthermore, the concentration of the BCG + ICL stellar mass, defined by the ratio of stellar mass within 10 kpc to the total stellar mass within 100 kpc, decreases with increasing M500, c at all z. We interpret this result as evidence for inside–out growth of the BCG + ICL over the past 10 Gyr, with stellar mass assembly occurring at larger radii at later times. [ABSTRACT FROM AUTHOR]

Resource polymorphism—whereby ancestral generalist populations give rise to several specialised morphs along a resource gradient—is common where species colonise newly formed ecosystems. This phenomenon is particularly well documented in freshwater fish populations inhabiting postglacial lakes formed at the end of the last ice age. However, knowledge on how such differential exploitation of resources across contrasting habitats might be reflected in the biochemical compositions of diverging populations is still limited, though such patterns might be expected. Here, we aimed to assess how fatty acids (FA)—an important biochemical component of animal tissues—diverged across a polymorphic complex of European whitefish (Coregonus lavaretus) and their closely related monomorphic specialist congener vendace (Coregonus albula) inhabiting a series of six subarctic lakes in northern Fennoscandia. We also explored patterns of FA composition in whitefish's predators and invertebrate prey to assess how divergence in trophic ecology between whitefish morphs would relate to biochemical profiles of their key food web associates. Lastly, we assessed how information on trophic divergence provided by differential FA composition compared to evidence of resource polymorphism retrieved from more classical stomach content and stable isotopic (δ13C, δ15N) information. Examination of stomach contents provided high-resolution information on recently consumed prey, whereas stable isotopes indicated broad-scale patterns of benthic-pelagic resource use differentiation at different trophic levels. Linear discriminant analysis based on FA composition was substantially more successful in identifying whitefish morphs and their congener vendace as distinct groupings when compared to the other two methods. Three major FA (myristic acid, stearic acid, and eicosadienoic acid) proved particularly informative, both in delineating coregonid groups, and identifying patterns of pelagic-benthic feeding throughout the wider food web. Myristic acid (14:0) content and δ13C ratios in muscle tissue were positively correlated across fish taxa, and together provided the clearest segregation of fishes exploiting contrasting pelagic and benthic niches. In general, our findings highlight the potential of FA analysis for identifying resource polymorphism in animal populations where this phenomenon occurs, and suggest that this technique may provide greater resolution than more traditional methods typically used for this purpose. [ABSTRACT FROM AUTHOR]

Mercury is a highly toxic element for consumers, but its relation to amino acids and physiology of wild fish is not well known. The main aim of this study was to evaluate how total mercury content (THg) of northern pike (Esox lucius) is related to amino acids and potentially important environmental and biological factors along a climate-productivity gradient of ten subarctic lakes. Linear regression between THg and sixteen amino acids content [nmol mg−1 dry weight] from white dorsal muscle of pike from these lakes were tested. Lastly, a general linear model (GLM) for age-corrected THg was used to test which factors are significantly related to mercury content of pike. There was a positive relationship between THg and proline. Seven out of sixteen analysed amino acids (histidine, threonine, arginine, serine, glutamic acid, glycine, and aspartic acid) were significantly negatively related to warmer and more productive lakes, while THg showed a positive relationship. GLM model indicated higher THg was found in higher trophic level pike with lower cysteine content and inhabiting warmer and more productive lakes with larger catchment containing substantial proportion of peatland area. In general, THg was not only related to the biological and environmental variables but also to amino acid content. [Display omitted] • Amino acids (AA) and total mercury (THg) were measured in pike from subarctic lakes. • Effects of environmental and ecological factors on THg content were tested. • THg content had a significant positive correlation with proline in pike muscle. • Content of seven AA in pike decreased towards warmer and more productive lakes. • THg was related to climate and productivity, catchment, trophic level, and cysteine. [ABSTRACT FROM AUTHOR]

This paper presents a multibeam dual-circularly polarized (CP) reflectarray for connected and autonomous vehicles. The developed reflectarray uses one aperture to realize dual-band and multibeam operation. At each frequency band, there are two simultaneously shaped beams with different circular polarizations. Totally four beams are obtained with a single feed and each of the beams can be independently controlled. A simple but effective polarization suppression technique is introduced to suppress cross polarizations at large scan angles so the CP beam of the reflectarray can be configured to point at large angles. Thus, the present reflectarray is suitable to be applied to vehicles for reliable high data-rate satellite communications. To validate the design concept, an X-band prototype was designed, fabricated, and measured. The design concept is flexible and can be applied to the design of dual-band, dual-CP reflectarray with different frequencies ratios. Moreover, the present design can also be extended to a continuous beam-steering design by incorporating phase shifters. [ABSTRACT FROM AUTHOR]

Abstract Metal matrix nanocomposites were fabricated by high-pressure torsion (HPT) using 5% graphene nanoplates as a reinforcement contained within an Al matrix. Powders were mixed and compacted at room temperature and then processed by HPT at three different temperatures of 298, 373 and 473 K. After processing, microstructural observations were undertaken to reveal the distributions of graphene in the matrix, the grain refinement in the aluminium and the nature of the graphene-aluminium interfaces. Tests were performed to measure the microhardness, the tensile stress-strain curves and the electrical conductivity. The results show that processing by HPT is advantageous because it avoids the sintering and high temperature deformation associated with other processing routes. Graphical abstract Image 1 [ABSTRACT FROM AUTHOR]

Arctic charr ( Salvelinus alpinus) is generally considered an inferior piscivore compared to brown trout ( Salmo trutta). However, we demonstrate that a recently described profundal spawning piscivore PP-morph of Arctic charr in a subarctic lake has evolved typical piscivore traits (i.e. large jaws, robust skulls), similar to the co-occurring brown trout but different from the sympatric littoral spawning omnivore LO-morph of Arctic charr. A few large-sized LO-morph, most large-sized PP-morph and trout constitute the piscivore guild, but they differed in prey fish selection. Of the fish-eating deep-water PP-morph, 52% had consumed charr, with a peak during the polar night period (68-80% in November-January). In contrast, the LO-morph and trout were mainly (~90%) inter-specific piscivores eating stickleback. Consequently, the PP-morph was the main charr predator and started to feed on fish at a smaller size and took larger prey relative to their body length than the trout. Stable isotope (δC, δN) ratios reflect the dietary specialisations in the upper-water (LO-morph, trout) and the deep-water (PP-morph) environments, besides the piscivorous behaviour of the PP-morph and trout. The existence of a shallow-water piscivore (trout) may explain the origin of this PP-morph, taking benefit of underutilised resources of small-sized Arctic charr in the deep-water habitat. [ABSTRACT FROM AUTHOR]

A population of small-sized Arctic charr living their entire life cycle in deep water was recently found in Lake Skogsfjordvatn, Northern Norway. Their phenotype and life history closely resembles the profundal charr morph in another subarctic Norwegian lake, Fjellfrøsvatn. Fjellfrøsvatn has one littoral omnivorous and one small profundal benthivorous (PB) charr morph coexisting with brown trout, whereas Skogsfjordvatn has migratory salmon, trout, charr and eel populations in addition to threespined sticklebacks, resident trout and three resident charr morphs of which one is a large piscivorous profundal morph. We predicted that the small profundal charr morph in Skogsfjordvatn would have a similar trophic niche to the PB-morph in Fjellfrøsvatn and tested this by using stomach content and stable isotope (δC and δN) analyses. Profundal benthic invertebrates, mainly chironomid larvae, Pisidium sp. mussels and small crustaceans, dominated the diets, and the δC and δN values indicated almost identical long-term trophic niches of the PB-morphs in both lakes. The prediction was therefore supported. This seems to indicate that the small profundal Arctic charr morphs in these lakes have evolved in parallel, in nearly identical and stable habitat and dietary niches in spite of likely different ecological interactions within the contrasting fish communities. [ABSTRACT FROM AUTHOR]