Trophodynamics of krill and its potential role in blue whale feeding in the Perth Canyon, south-east Indian Ocean

Migrating blue whales along the Western Australian coast exhibit feeding behaviour within the Perth Canyon, which is an area of high krill abundance, particularly for Euphausia recurva. The importance of krill in marine food webs has led to a number of trophodynamic studies investigating their fatty acid and stable isotope compositions. In the south-east Indian Ocean, the suppression of upwelling by the dominant Leeuwin Current results in relatively oligotrophic waters, particularly during autumn and winter. Oligotrophic waters tend to be dominated by small autotrophic flagellates (i. e. dinoflagellates) and cyanobacteria. We relate biochemical data obtained for E. recurva, as well as Stylocheiron carinatum and Pseudeuphausia latifrons with their potential food source, phytoplankton, and one of their potential predators, the endangered pygmy blue whale (Balaenoptera musculus brevicauda) sampled in the Perth Canyon. Fatty acids of all three krill species were dominated by polyunsaturated fatty acids (PUFA; ~50%) largely comprised of omega-3 PUFA, which is typical for krill. The high docosahexaenoic acid (DHA) to eicosapentaenoic acid (EPA) ratio reflects a dinoflagellate, rather than a diatom diet, and the high oleic acid (18: 1 9) to vaccenic acid (18: 1 7) ratio is indicative of an omnivorous diet. Stable isotope analysis positions E. recurva as a first, possibly second order consumer (5. 8 - 8. 4 15N)and phytoplankton as the likely source of carbon (-18 to -24 13C) .The fatty acid composition of krill did not match that of the surface phytoplankton sampled, which was low in PUFA and more reflective of degraded and detrital material. This suggests that krill are not feeding at the surface, and may feed closer to the deep chlorophyll maximum. The outer blubber layer sampled from the pygmy blue whale was high in monounsaturated fatty acids (MUFA, 58%) rather than PUFA, and did not reflect the krill fatty acid composition. However, the high DHA to EPA ratio in the blubber indicated a diet originating from dinoflagellates, as found for krill. Stratification of fatty acids across blubber layers is common for marine mammals and the outer blubber layer for some species has been found to not accurately reflect the diet of the animal

A Stratabound Zinc-Lead Deposit in Meguma Group Metasediments at Eastville, Nova Scotia

The Eastville zinc-lead deposit, discovered by soil sampling in 1976, occurs near the contact of the Goldenvllle and Halifax Formations, the two divisions of the Cambro-Ordovician Meguma Group. The stratigraphic succession in the contact zone comprises an assemblage of quartz metawacke, calcareous quartz metawacke and slate. Quartz metawacke is predominant in the Goldenvllle Formation and slate is the dominant lithology in the overlying Halifax Formation. These rocks are interpreted as the middle to outer fan and basin plain deposits of a submarine fan complex. Pyrrhotite and pyrite, the predominant Bulphide minerals in all lithologles in the contact zone, were deposited by reduction of iron in the sediments, independent of the mineralizing process. Sphalerite and galena occur in rocks over a 10 km strike length in elongate blebs, 2 to 5 mm long, distributed parallel to bedding and in cross-cutting fractures. The deposit is stratabound and generally occurs in black slate beds near the Goldenvllle-Halifax contact. Geochemical analyses of the rocks have indicated a concentration of Mn in the calcareous quartzite member, the upper unit of the Goldenville Formation. A relationship between the Mn enrichment and the abundance of sphalerite and galena in the section has not been established. The sulphide mineralogy, laterally continuous stratigraphy and lack of metal zonation and underlying feeder structures indicate the sphalerite and galena were syngenetically deposited from metal-rich brines at a site distant from where the brines entered the basin of deposition- RÉSUMÉ Le dépôt de plomb at de zinc de Eastville, qui a été découvert par des prises d'échantillons de terre en 1976, est situé pré du contact des formations Goldenville et Halifax (les deux unités du groupe Meguma). La succession stratigraphique dans la zone de contact est constitué d'un assemblage de métagrauwacke de quartz, de métagrauvacke calcaire de quartz, et d'ardoise. Le métagrauwacke de quartz est prédominant dans la formation Goldenville et l'ardoise est la lithologie dominate de la formation de Halifax, qui est superposé sur la première. Ces roches sont expllquées comme étant le cône central ou extérieur et des dépôts de la plaine d'un basin d'un compiexe de cône. La pyrrhotite et la pyrite, les minéraux sulfides principalis dans toutes les lithologles de la zone de contact, ont été déposés par une réduction de fer dans les sédiments, indépendement des processus de minéralisation. La sphalérite et la galène se trouvent dans les roches sur une longueur de 10 kilomètres le long de la couche en temps que soufflures de 2 à 5 mm de longueur, réparties paralèllement à la couche et dans les fractures à trafers banc. Le dépôt est limite aux strates et se crouve en général dans de l'ardoise noire près du contact Goldenville-Halifax. Des analyses géochimiques des roches ont indiqué une concentration de Mn dans les quartzites calcaires, l'unité la plus é1evé de la formation Goldenville. Un rapport entre l'enrichiasement en Mn et l'abondance de la sphalerite et de la galène dans la section, n'a pas été établie. La minéralogie des sulfides, la stratigraphie laterale continue, et le manque de zonation de métaux et de structures de conduite d'alimentation, indique que la sphalerite et la galène ont été déposées sygénétiquement à partir de saumures riches en métaux dans un site éloigné de l'endroit où les saumures pénétrent le basin de dépôt. [Traduit par le journal

Binge-watching: Video-on-demand, quality TV and mainstreaming fandom

This article explores the concept of the binge as viewing protocol associated with fan practices, industry practice and linked to ‘cult’ and ‘quality’ serialised content. Viewing binge-watching as an intersection of discourses of industry, audience and text, the concept is analysed here as shaped by a range of issues that dominate the contemporary media landscape. In this, factors like technological developments, fan discourses and practices being adopted as ‘mainstream’ media practice, changes in the discursive construction of ‘television’ and an emerging Video-on-Demand industry contribute to the construction of binge-watching as deliberate, self-scheduled alternative to ‘watching TV’

Avoiding a bad apple: insect pollination enhances fruit quality and economic value

Insect pollination is important for food production globally and apples are one of the major fruit crops which are reliant on this ecosystem service. It is fundamentally important that the full range of benefits of insect pollination to crop production are understood, if the costs of interventions aiming to enhance pollination are to be compared against the costs of the interventions themselves. Most previous studies have simply assessed the benefits of pollination to crop yield and ignored quality benefits and how these translate through to economic values. In the present study we examine the influence of insect pollination services on farmgate output of two important UK apple varieties; Gala and Cox. Using field experiments, we quantify the influence of insect pollination on yield and importantly quality and whether either may be limited by sub-optimal insect pollination. Using an expanded bioeconomic model we value insect pollination to UK apple production and establish the potential for improvement through pollination service management. We show that insects are essential in the production of both varieties of apple in the UK and contribute a total of £36.7 million per annum, over £6 million more than the value calculated using more conventional dependence ratio methods. Insect pollination not only affects the quantity of production but can also have marked impacts on the quality of apples, influencing size, shape and effecting their classification for market. These effects are variety specific however. Due to the influence of pollination on both yield and quality in Gala, there is potential for insect pollination services to improve UK output by up to £5.7 million per annum. Our research shows that continued pollinator decline could have serious financial implications for the apple industry but there is considerable scope through management of wild pollinators or using managed pollinator augmentation, to improve the quality of production. Furthermore, we show that it is critically important to consider all production parameters including quality, varietal differences and management costs when valuing the pollination service of any crop so investment in pollinator management can be proportional to its contribution

Річард Смоллі і знамениті «десять вересневих днів»

У вересні цього року виповнюється 27 років, як було відкрито фулерен — нову сфероподібну форму вуглецю. Ця подія буквально приголомшила вчених, які на той час вважали, що про елементарний вуглець їм відомо практично все. Історія відкриття цієї речовини досить незвичайна. Ще в 1971 р. можливість існування молекули фулерену була передбачена японським ученим Е. Осавою (E. Osawa), за два роки радянські хіміки-теоретики Д.А. Бочвар і О.Г. Гальперн квантово-хімічними розрахунками підтвердили стабільність молекули С60, і лише у 1985 р. Р. Смоллі, Р. Керл та Г. Крото експериментально отримали кластери із 60 атомів вуглецю в стійкій формі, яку вони пояснили структурою молекули у вигляді футбольного м’яча. Натхненнику цього відкриття, видатному вченому, нобелівському лауреату, активному популяризатору нанотехнологій Річарду Смоллі присвячено цей матеріал.В сентябре этого года исполняется 27 лет с момента открытия фуллерена — новой сферообразной формы углерода. Это событие буквально потрясло ученых, которые в то время считали, что об элементарном углероде им известно практически все. История открытия этого вещества довольно необычна. Еще в 1971 г. возможность су ществования молекулы фуллерена была предсказана японским ученым Е. Осавой (E. Osawa), через два года советские химики-теоретики Д.А. Бочвар и Е.Г. Гальперн с помощью квантово-химических расчетов подтвердили стабильность молекулы С60, и только в 1985 г. Р. Смолли, Р. Керл и Г. Крото экспериментально получили кластеры из 60 атомов углерода в устойчивой форме, которую они объяснили структурой молекулы в виде футбольного мяча. Вдохновителю этого открытия, выдающемуся ученому, нобелевскому лауреату, активному популяризатору нанотехнологий Ричарду Смолли посвящен этот материал.27 years since the discovery of fullerene, the new form of carbon, is observed in September of this year. This event has literally shocked scientists, who believed at that time that they know almost everything about the elementary carbon. History of this discovery is rather unusual. Long ago, in 1971 the possibility of the existence of a fullerene molecule was predicted by an young Japanese scientist E. Osawa. Then two Soviet chemists and theorists D.A. Bochvar and E.G. Hal pern confirm the stability of the C60 molecule using quantum chemical calculations, and in 1985 at last R. Smalley, R. Curl and H. Kroto experimentally obtained clusters of 60 carbon atoms in a sustainable form. They explained the structure of this molecule as the structure of a soccer ball. This material is devoted to the inspirer of this discovery, an outstanding scientist, Nobel laureate, active popularizer of nanotechnology — Richard Smalley

Heme ligation and redox chemistry in two bacterial thiosulfate dehydrogenase (TsdA) enzyme

Thiosulfate dehydrogenases (TsdA) are bidirectional bacterial di-heme enzymes that catalyze the interconversion of tetrathionate and thiosulfate at measurable rates in both directions. In contrast to our knowledge of TsdA activities, information on the redox properties in the absence of substrates is rather scant. To address this deficit, we combined magnetic circular dichroism (MCD) spectroscopy and protein film electrochemistry (PFE) in a study to resolve heme ligation and redox chemistry in two representative TsdAs. We examined the TsdAs from Campylobacter jejuni, a micro-aerobe human pathogen, and from the purple sulfur bacterium Allochromatium vinosum. In these organisms, the enzyme functions as a tetrathionate reductase and a thiosulfate oxidase respectively. The active site Heme 1 in both enzymes has His/Cys− ligation in the ferric and ferrous states and the midpoint potentials (Em) of the corresponding redox transformations are similar, −185 mV versus standard hydrogen electrode (SHE). However, fundamental differences are observed in the properties of the second, electron transferring, Heme 2. In C. jejuni TsdA Heme 2 has His/Met ligation and an Em of +172 mV. In A. vinosum TsdA, Heme 2 reduction triggers a switch from His/Lys ligation (Em, −129 mV) to His/Met (Em,+266 mV) but the rates of interconversion are such that His/Lys ligation would be retained during turnover. In summary, our findings have unambiguously assigned Em values to defined axial ligand sets in TsdAs, specified the rates of Heme 2 ligand exchange in the A. vinosum enzyme, and provided information relevant to describing their catalytic mechanism(s)

IUCF High Intensity Polarized Ion Source

This research was sponsored by the National Science Foundation Grant NSF PHY-931478

The IUCF Cooler Project

This research was sponsored by the National Science Foundation Grant NSF PHY 87-1440

Apple pollination: demand depends on variety and supply depends on pollinator identity

Insect pollination underpins apple production but the extent to which different pollinator guilds supply this service, particularly across different apple varieties, is unknown. Such information is essential if appropriate orchard management practices are to be targeted and proportional to the potential benefits pollinator species may provide. Here we use a novel combination of pollinator effectiveness assays (floral visit effectiveness), orchard field surveys (flower visitation rate) and pollinator dependence manipulations (pollinator exclusion experiments) to quantify the supply of pollination services provided by four different pollinator guilds to the production of four commercial varieties of apple. We show that not all pollinators are equally effective at pollinating apples, with hoverflies being less effective than solitary bees and bumblebees, and the relative abundance of different pollinator guilds visiting apple flowers of different varieties varies significantly. Based on this, the taxa specific economic benefits to UK apple production have been established. The contribution of insect pollinators to the economic output in all varieties was estimated to be £92.1M across the UK, with contributions varying widely across taxa: solitary bees (£51.4M), honeybees (£21.4M), bumblebees (£18.6M) and hoverflies (£0.7M). This research highlights the differences in the economic benefits of four insect pollinator guilds to four major apple varieties in the UK. This information is essential to underpin appropriate investment in pollination services management and provides a model that can be used in other entomolophilous crops to improve our understanding of crop pollination ecology