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Five genera of anthaspidellid and streptosollenid demosponges are described from the Ordovician Lenoir Limestone near Lenoir City, Loudon County, Tennessee, USA including: Rhopalocoelia regularis Raymond and Okulitch, Rugocoelia loudonensis n. sp., Psarodictyum sp. (Anthaspidellidae), Allosacus pedunculatus n. sp., and Zitelella varians Raymond and Okulitch (Streptosolenidae). These findings confirm the major paleobiogeographic picture for Laurentian sponges (i.e., the differential distribution of sponge faunas along both North American margins), because none of these eastern margin species has been reported from western margin faunas. Only one genus typical of the Great Basin fauna, Rugocoelia Johns, 1994, is reported from Tennessee, but as a new species. Possible explanations are discussed for this differential distribution, mainly related to climatic constraints or sedimentary differences, preventing the free distribution of sponge species between Laurentian continental margins.
In the 2015 review paper ‘Petawatt Class Lasers Worldwide’ a comprehensive overview of the current status of high-power facilities of
was presented. This was largely based on facility specifications, with some description of their uses, for instance in fundamental ultra-high-intensity interactions, secondary source generation, and inertial confinement fusion (ICF). With the 2018 Nobel Prize in Physics being awarded to Professors Donna Strickland and Gerard Mourou for the development of the technique of chirped pulse amplification (CPA), which made these lasers possible, we celebrate by providing a comprehensive update of the current status of ultra-high-power lasers and demonstrate how the technology has developed. We are now in the era of multi-petawatt facilities coming online, with 100 PW lasers being proposed and even under construction. In addition to this there is a pull towards development of industrial and multi-disciplinary applications, which demands much higher repetition rates, delivering high-average powers with higher efficiencies and the use of alternative wavelengths: mid-IR facilities. So apart from a comprehensive update of the current global status, we want to look at what technologies are to be deployed to get to these new regimes, and some of the critical issues facing their development.
Gaming disorder is set to be included in the International Statistical Classification of Diseases and Related Health Problems alongside other behavioural addictions (gambling disorder) and substance-related addictions. Given the popularity of online gaming, this is set to become an increasingly common presentation to general mental health professionals, addiction specialists, and general practitioners. This article briefly examines online gaming and describes the characteristics of gaming disorder. Some features of online gaming that have addictive potential and similarities to other addictive behaviours such as gambling disorder are discussed. Finally, the article examines treatment options available for gaming disorder and treatment going forward from an Irish perspective.
The residual closure of a subgroup H of a group G is the intersection of all virtually normal subgroups of G containing H. We show that if G is generated by finitely many cosets of H and if H is commensurated, then the residual closure of H in G is virtually normal. This implies that separable commensurated subgroups of finitely generated groups are virtually normal. A stream of applications to separable subgroups, polycyclic groups, residually finite groups, groups acting on trees, lattices in products of trees and just-infinite groups then flows from this main result.
The evolution of glaciers and ice sheets depends on processes in the subglacial environment. Shear seismicity along the ice–bed interface provides a window into these processes. Such seismicity requires a rapid loss of strength that is typically ascribed to rate-weakening friction, i.e., decreasing friction with sliding or sliding rate. Many friction experiments have investigated glacial materials at the temperate conditions typical of fast flowing glacier beds. To our knowledge, however, these studies have all found rate-strengthening friction. Here, we investigate the possibility that rate-weakening rock-on-rock friction between sediments frozen to the bottom of the glacier and the underlying water-saturated sediments or bedrock may be responsible for subglacial shear seismicity along temperate glacier beds. We test this ‘entrainment-seismicity hypothesis’ using targeted laboratory experiments and simple models of glacier sliding, seismicity and sediment entrainment. These models suggest that sediment entrainment may be a necessary but not sufficient condition for the occurrence of basal shear seismicity. We propose that stagnation at the Whillans Ice Stream, West Antarctica may be caused by the growth of a frozen fringe of entrained sediment in the ice stream margins. Our results suggest that basal shear seismicity may indicate geomorphic activity.
The atrypide brachiopod Schachriomonia is documented here for the first time from the upper Katian Hadabulaktag Formation on the northeastern edge of Tarim Basin in Northwest China. These shells are conspecific with the earlier reported Rhynchotrema pentagonia Fang in Liu and Fang, 1990 from the same region. This species is most similar to Schachriomonia parva Popov et al., 1999 described from the Upper Ordovician of the Chu-Ili and Chingiz terranes and less closely resembles species from North and South China, indicating a close paleogeographic connection between these plates and terranes and Tarim during the Late Ordovician. Its dominance at three horizons in the study area may indicate that this species was an opportunistic colonizer of the seafloor following ecological disruption, or alternatively that the larvae were substrate-selective. Variation in shell shape from a nearly circular shell outline with a dorsal sulcus and ventral fold in the smallest shells to a wider outline with a more reversed dorsal fold and ventral sulcus in the largest is an example of ontogenic development. This may have been an adaptation to accommodate the growing lophophore or development of gonads in the mantle cavity over the life of the brachiopod. A stronger tooth-socket connection in larger shells strengthened the hinge area to better withstand the stresses caused by the mass of a larger shell.
Neglected tropical diseases (NTDs) share certain traits: they are parasitic infections, prevailing in tropical environments and affecting marginalized sectors of the population. Six NTDs – ascariasis, cysticercosis, echinococcosis, hookworm infection, onchocerciasis and trichuriasis – all of them endemic in Latin America and the Caribbean (LAC), are analysed in this work. This review aims to discuss key information on the function of excretory/secretory (E/S) proteins from these parasites in their infectivity, pathogeny and diagnosis. The modulation of the host immune system to favour the permanence and survival of the parasite is also discussed. An updated knowledge on the function of E/S molecules in endemic parasitoses in LAC may lead to new approaches for the clinical management and diagnosis of these diseases. In turn, this could allow us to optimize their treatment and make it more affordable – a relevant goal given the economic constraints that the region is facing.
The phylogenetic relationships of Paleozoic blastozoan echinoderms are poorly understood and many of the traditionally ascribed groups are likely polyphyletic. Diploporitans, those blastozoans with double pore (diplopore) respiratory structures, have never been placed within a rigorous phylogenetic framework, and their highly variable morphologies suggest that they do not represent a natural clade. A maximum parsimony phylogenetic analysis, spanning a wide range of diploporitan and related taxa, indicates that diplopore-bearing blastozoans are a polyphyletic grouping and, consequently, that diplopore respiratory structures have evolved more than once within the echinoderms. Constraint analyses indicate that a single diplopore-bearing clade bearing the traditionally defined Glyptosphaeritida, Sphaeronitida, Asteroblastida is less parsimonious than multiple diplopore-bearing clades inferred by the unconstrained analysis.
40% of people with dementia have disturbed sleep but there are currently no known effective treatments. Studies of sleep hygiene and light therapy have not been powered to indicate feasibility and acceptability and have shown 40–50% retention. We tested the feasibility and acceptability of a six-session manualized evidence-based non-pharmacological therapy; Dementia RElAted Manual for Sleep; STrAtegies for RelaTives (DREAMS-START) for sleep disturbance in people with dementia.
We conducted a parallel, two-armed, single-blind randomized trial and randomized 2:1 to intervention: Treatment as Usual. Eligible participants had dementia and sleep disturbances (scoring ≥4 on one Sleep Disorders Inventory item) and a family carer and were recruited from two London memory services and Join Dementia Research. Participants wore an actiwatch for two weeks pre-randomization. Trained, clinically supervised psychology graduates delivered DREAMS-START to carers randomized to intervention; covering Understanding sleep and dementia; Making a plan (incorporating actiwatch information, light exposure using a light box); Daytime activity and routine; Difficult night-time behaviors; Taking care of your own (carer's) sleep; and What works? Strategies for the future. Carers kept their manual, light box, and relaxation recordings post-intervention. Outcome assessment was masked to allocation. The co-primary outcomes were feasibility (≥50% eligible people consenting to the study) and acceptability (≥75% of intervention group attending ≥4 intervention sessions).
In total, 63out of 95 (66%; 95% CI: 56–76%) eligible referrals consented between 04/08/2016 and 24/03/2017; 62 (65%; 95% CI: 55–75%) were randomized, and 37 out of 42 (88%; 95% CI: 75–96%) adhered to the intervention.
DREAM-START for sleep disorders in dementia is feasible and acceptable.
Altaethyrella tarimensis, a new species of rhynchonellide brachiopod, is described from the late Katian (Late Ordovician) Hadabulaktag Formation in the Kuruktag region of Xinjiang, Northwest China on the northeastern edge of the Tarim Basin. Serial sections of the shell clearly show no dorsal median septum or septalium in the dorsal valve, and no spiralia or atrypide-style crura. Like other species of the genus, A. tarimensis n. sp. exhibits a high degree of intraspecific variation, including variations in shell shape and size, number of ribs in the sulcus at the anterior, and degree of asymmetry. The discovery of Altaethyrella in Tarim has important paleogeographic implications, indicating a close relationship between the Late Ordovician brachiopod faunas of Tarim and those of the Kazakh terranes and North and South China paleoplates, supporting a recently published paleogeographic projection that places Tarim near the Chu-Ili terrane during the Late Ordovician. The abundant large biconvex shells of A. tarimensis n. sp. would have provided a firm substrate for encrusting filter feeders like bryozoans to establish on the Kuruktag Platform.
Schmidite, Zn(Fe3+0.5Mn2+0.5)2ZnFe3+(PO4)3(OH)3(H2O)8 and wildenauerite, Zn(Fe3+0.5Mn2+0.5)2Mn2+Fe3+(PO4)3(OH)3(H2O)8 are two new oxidised schoonerite-group minerals from the Hagendorf-Süd pegmatite, Hagendorf, Oberpfalz, Bavaria, Germany. Schmidite occurs as radiating sprays of orange–brown to copper-red laths on and near to altered phosphophyllite in a corroded triphylite nodule, whereas wildenauerite forms dense compacts of red laths, terminating Zn-bearing rockbridgeite. The minerals are biaxial (+) with α = 1.642(2), β = 1.680(1), γ = 1.735(2) and 2Vmeas = 81.4(8)° for schmidite, and with α = 1.659(3), β = 1.687(3), γ = 1.742(3) and 2Vmeas = 73(1)° for wildenauerite. Electron microprobe analyses, with H2O from thermal analysis and FeO/Fe2O3 from Mössbauer spectroscopy, gave FeO 0.4, MgO 0.3, Fe2O3 23.5, MnO 9.0, ZnO 15.5, P2O5 27.6, H2O 23.3, total 99.6 wt.% for schmidite, and FeO 0.7, MgO 0.3, Fe2O3 25.2, MnO 10.7, ZnO 11.5, P2O5 27.2, H2O 24.5, total 100.1 wt.% for wildenauerite. The empirical formulae, scaled to 3 P and with OH– adjusted for charge balance are Zn1.47Mn2+0.98Mg0.05Fe2+0.04Fe3+2.27(PO4)3(OH)2.89(H2O)8.54 for schmidite and Zn1.11Mn2+1.18Mg0.05Fe2+0.08Fe3+2.47(PO4)3(OH)3.25(H2O)9.03 for wildenauerite. The two minerals have orthorhombic symmetry, space group Pmab and Z = 4. The unit-cell parameters from refinement of powder X-ray diffraction data are a = 11.059(1), b = 25.452(1) and c = 6.427(1) Å for schmidite, and a = 11.082(1), b = 25.498(2) and c = 6.436(1) Å for wildenauerite. The crystal structures of schmidite and wildenauerite differ from that of schoonerite in having minor partitioning of Zn from the Zn site to an adjacent vacant tetrahedral site Zn, separated by ~1.0 Å from Zn. The two minerals are distinguished by the cation occupancies in the octahedral M1 to M3 sites. Schmidite has M1 = M2 = (Fe3+0.5Mn2+0.5) and M3 = Zn and wildenauerite has M1 = M2 = (Fe3+0.5Mn2+0.5) and M3 = Mn2+.
The merits of solar coronal at metric-wavelength (MW) radio have long been recognised (e.g. Pick and Vilmer, 2008). High-fidelity solar radio imaging at these frequencies has however remained challenging. On the one hand, dealing with the small spectral and temporal scales of variation in solar radio emission requires a data product capable of tracking the emission simultaneously across time, frequency and morphology. The Fourier imaging nature of interferometry, on the other hand, severely limits the instrumental ability to gather sufficient information to do this with the required fidelity and resolution. Benefiting from the enormous advances in technology the new generation of instruments, like the Murchison Widefield Array (MWA; Tingay et al. (2013), Bowman et al. (2013)), represent a quantum leap in our ability to gather data suitable for radio solar physics.
At low radio frequencies the solar corona is very dynamic in both spectral and temporal domains. To capture the fine details of this complex dynamics, imaging studies at high temporal and spectral resolution are necessary. The advent of the new instruments like the Murchison Widefield Array (MWA; Tingay et al. 2013, Bowman et al. 2013), is now making this possible.