Recent work in the district of Kaupō, Maui, has demonstrated the presence of a highly intensified dryland agricultural system, extensive residential sites and a range of ceremonial structures that ...include some of the largest temples (heiau) in the Hawaiian Islands. In this paper I discuss the ritual sites of Kaupō and how their placement on the landscape demonstrates a unique expression of elite power. Using formal architectural features to define two basic classes of ritual sites, I show that the nutrient-rich core of the district is bounded on either side by a network of monumental temples, effectively proscribing the highly productive interior. In contrast to these major heiau around the exterior, the interior of the district is dominated almost exclusively by small, relatively simple ceremonial spaces. Understanding the differential distribution of the ritual structures in Kaupō offers insights into how pre-contact Hawaiian rulers sought to centralise and control highly productive regions.
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California's coastal climate is characterized by rainy winters followed by a dry summer season that is supplemented by frequent fog. While rising temperatures and drought caused massive tree ...mortality in central California during the 2011-2015 extreme drought, dying trees were less common in the central coast region. We hypothesized that cooler, maritime-ameliorated temperatures reduced the effects of drought stress on coastal vegetation. To test this, weekly measurements of water potential and stomatal conductance were made on two coast evergreen tree species, Arbutus menziesii and Quercus agrifolia, throughout the summer 2014 dry season. Water potential remained generally constant during this period but stomatal conductance declined in both species as the dry season progressed. Species' resistance to embolism was determined using the centrifuge method, and showed Q. agrifolia to be more vulnerable to embolism than A. menziesii. The stem vulnerability curves were consistent with species' seasonal water relations as well as their anatomy; the ring-porous Q. agrifolia had substantially larger conduits than the diffuse-porous A. menziesii. Leaf turgor loss points differed significantly as did other pressure-volume parameters but these data were consistent with the trees' seasonal water relations. Overall, the two species appear to employ differing water use strategies; A. menziesii is more profligate in its water use, while Q. agrifolia is more conservative, with a narrower safety margin against drought-induced loss of xylem transport capacity. Despite the extended drought, these species exhibited neither branch die-back nor any obvious symptoms of pronounced water-stress during the study period, implying that the maritime climate of California's central coast may buffer the local vegetation against the severe effects of prolonged drought.
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DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
Velvet worms eject a fluid capture slime that can be mechanically drawn into stiff biopolymeric fibres. Remarkably, these fibres can be dissolved by extended exposure to water, and new regenerated ...fibres can be drawn from the dissolved fibre solution-indicating a fully recyclable process. Here, we perform a multiscale structural and compositional investigation of this reversible fabrication process with the velvet worm Euperipatoides rowelli, revealing that biopolymeric fibre assembly is facilitated via mono-disperse lipid-protein nanoglobules. Shear forces cause nanoglobules to self-assemble into nano- and microfibrils, which can be drawn into macroscopic fibres with a protein-enriched core and lipid-rich coating. Fibre dissolution in water leads to re-formation of nanoglobules, suggesting that this dynamic supramolecular assembly of mechanoresponsive protein-building blocks is mediated by reversible non-covalent interactions. These findings offer important mechanistic insights into the role of mechanochemical processes in bio-fibre formation, providing potential avenues for sustainable material fabrication processes.Velvet worms expel a fluid slime that, under shear force, forms stiff fibres that can be dissolved and then regenerated. Here, the authors reveal that the recyclability of these biopolymers relies on mechanoresponsive lipid-protein nanoglobules in the slime that reversibly self-assemble into fibrils.
Energy storage technologies are increasingly being deployed in Alberta. In the recent past, costs were the largest hurdle to widespread energy storage deployment. But this is changing given falling ...battery prices. Indeed, the Alberta Electric System Operator (AESO) and the Alberta Utilities Commission (AUC) processes are increasingly considering energy storage development and potential but within the scope of existing legislation and its policy framework. Alberta's traditional model of electricity regulation is based on generators supplying electricity to load customers for consumption and does not directly contemplate the unique attributes of energy storage. These attributes include the flexibility of customers to switch between supply and load, such as where a customer discharges a battery into the grid during peak hours and charges the battery during off-peak hours.
Energy market participants and policy-makers need to consider the use of flexible resources in an evolving electricity industry where distributed and intermittent power sources are increasingly prominent. Energy storage is playing a key role in this ongoing evolution. To that end, this article seeks to provide practitioners and industry stakeholders guidance on the current state of the Alberta regulatory landscape applicable to energy storage and anticipated changes.
Specifically, this article sets out the regulatory framework applicable to, and policy issues raised by, energy storage, including tariffs and competitive market issues, the concept of "hybrid sites" and self-supply and export issues, and AUC decisions approving the deployment of energy storage. As to how the landscape may change, this article looks at recent policy statements by the AUC and the AESO describing potential changes on the horizon.
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The Hawaiian people before Western contact gathered at special places during the Makahiki period, a time that was sacred to the god Lono, and during which sports, games and other ceremonies took ...place. Archaeological excavation and archaeoastronomical investigation together suggest that an approximately 40 m² rock enclosure in the uplands of Honouliuli on the island of O'ahu was such a special gathering place. Radiocarbon dating indicates that the enclosure was most likely constructed between the late AD 1500s and early AD 1600s, with a notable period of use during the mid-AD 1600s. The archaeoastronomical evidence supports this conclusion, in that the enclosure is precisely aligned upon the horizon rising point in AD 1600 of the Pleiades star cluster (Makali'i in Hawaiian), whose first appearance each November marked the beginning of the four-month Makahiki "annnual harvest" period dedicated to the god Lono. That time period saw the peaking and stabilisation of population on O'ahu, and the expansion of settlements into marginal environmental zones such as Honouliuli. A significant number of temples built around the same time on the island of Maui are oriented in a similar manner.
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The first synthesis of the proposed natural stereoisomer of halisphingosine A, a metabolite of the marine sponge
Haliclona tubifera
, was accomplished in 11 steps including an enantioselective Henry ...reaction, a Weinreb amide - acetylide coupling, and stereoselective reductions of the resulting ynone to afford the
R
,
Z
-configured allyl alcohol moiety. The synthetic product differed from the natural isolate in some
13
C-NMR data. It showed antiproliferative activity at clinically relevant concentrations against six tumour cell lines including such lacking functional tumor suppressor gene p53.
The purported isomer of halisphingosine A was built up in 11 steps and 29% yield by catalytic Henry and hydrogenation reactions. Its
13
C-NMR data differed from that of the natural isolate. It was antiproliferative in various tumour cells.
The first total synthesis of bathymodiolamides A and B, ceramide-like metabolites of the deep-sea hydrothermal vent mussel
, was accomplished in eight linear steps starting from Garner's aldehyde and ...three carboxylic acids. A sequence of vinylation of Garner's aldehyde, N-acylation with lauric acid, dihydroxylation of the terminal alkene, and stepwise Steglich-Hassner esterifications of the resulting vicinal diol with the respective saturated and unsaturated carboxylic acids, which had to be prepared separately, afforded the target products in 38 and 39% yield. We found distinct discrepancies between their NMR data and antiproliferative activities and those reported for the natural isolates.
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For prey capture and defense, velvet worms eject an adhesive slime which has been established as a model system for recyclable complex liquids. Triggered by mechanical agitation, the liquid ...bio‐adhesive rapidly transitions into solid fibers. In order to understand this mechanoresponsive behavior, here, the nanostructural organization of slime components are studied using small‐angle scattering with neutrons and X‐rays. The scattering intensities are successfully described with a three‐component model accounting for proteins of two dominant molecular weight fractions and nanoscale globules. In contrast to the previous assumption that high molecular weight proteins—the presumed building blocks of the fiber core—are contained in the nanoglobules, it is found that the majority of slime proteins exist freely in solution. Only less than 10% of the slime proteins are contained in the nanoglobules, necessitating a reassessment of their function in fiber formation. Comparing scattering data of slime re‐hydrated with light and heavy water reveals that the majority of lipids in slime are contained in the nanoglobules with homogeneous distribution. Vibrating mechanical impact under exclusion of air neither leads to formation of fibers nor alters the bulk structure of slime significantly, suggesting that interfacial phenomena and directional shearing are required for fiber formation.
Small‐angle neutron scattering reveals the nanoscale organization of velvet worm slime. The rapid, mechanically induced transition of this liquid bioadhesive into stiff fibers is based on the self‐assembly of proteins that are freely localized in solution. Nanoglobules, the previously assumed storage units for these fiber precursors, only contain small amounts of proteins and lipids.
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