460 research outputs found
Melithaea cervicornis Watling 2020, n. comb.
No full text<i>Melithaea cervicornis</i> (Thomson & Dean, 1931) n. comb. <p>(Figs. 5–7)</p> <p> <i>Muricellisis cervicornis</i> Thomson & Dean, 1931</p> <p> <b>Diagnosis.</b> Colony with irregular branching, axis white, nodes gold-colored. Polyps fully retractable into calyx. Sclerites spindles or flattened spindles with large tubercles.</p> <p> <b>Type specimen.</b> Zoölogisches Museum Amsterdam.</p> <p> <b>Type locality.</b> Siboga Expedition, Station 139, 0° 11’ S, 127° 25’ E., in channel between Pulau Bacan and Pulau Laluin in the South Halamahara Regency, Indonesia. Depth, 397 m.</p> <p> <b>Description.</b> Only a few fragments, totaling 12 cm, of this species were collected (Fig. 5a, d). The diameter of the largest axis fragment is 3.6 mm, that with the polyps is 1.3 mm. Most fragments have no polyps.About 30 polyps are present. The polyps are mostly retracted into a calyx of 1–1.5 mm diameter and 0.5 mm height (Fig. 5e, f).</p> <p>The axis is typical for the family, with elongate (~ 5–12 mm) internodes interrupted by short (~ 1 mm long), golden nodes (Fig. 6a). The internodes are solid with an exterior layer of elongate stick-like sclerites 0.16–0.35 mm in length (Fig. 6 b–d). The nodes are of the same diameter as the internodes and contain numerous short (0.75– 0.13 mm), smooth rods embedded in a thin organic matrix (Fig 6e,f).</p> <p> The sclerites of the coenenchyme and calyx (Fig. 7d, e) are simple, densely tuberculate, somewhat flattened plates or more elongate, tuberculate rods up to 0.4 mm length. No clubs or other complex sclerites typical of the genus <i>Melithaea</i> were found. Sclerites on the upper part of the polyp are long, curved rods or flat rods, up to 0.41 mm in length, arranged in a collaret and points. Those of the points are more tuberculate and shorter (up to 0. 32 mm length) than those of the collaret (Fig. 7b,c). Tentacle sclerites are flattened tuberculate rods (Fig. 7a) up to 0.17 mm length. No sclerites were retrieved from the pharynx.</p> <p> <b>Remarks.</b> The construction of the axis and nodes is typical of the genus <i>Melithaea</i>. In particular, the small, smooth rods in the node are similar to those seen in other members of the genus. On the other hand, the relative simplicity of the sclerites is uncommon, occurring only in one or a few other <i>Melithaea</i> species.</p> <p> <i>Melithaea cervicornis</i> is most similar to <i>M. modesta</i> from Japan (Matsumoto and Ofwegen, 2015) in the lack of clubs in the calyx and well as the look of the axis and nodes. However, the two species differ in the degree and form of the tuberculation on the sclerites. In <i>M. cervicornis</i> the tubercles are large, rounded, and crowded whereas in <i>M. modesta</i> they are taller, more spine-like, and more widely spaced (the distance between the tubercles being larger than the tubercle diameter). The two species are found in different biogeographic provinces (Watling <i>et al.</i>, 2013; Summers and Watling, in press), but could be closely related taxa.</p>Published as part of <i>Watling, Les, 2020, Toward a revision of the bamboo corals: Part 1, species in the Muricellisidinae (Octocorallia: Isididae), pp. 361-371 in Zootaxa 4881 (2)</i> on pages 367-368, DOI: 10.11646/zootaxa.4881.2.9, <a href="http://zenodo.org/record/4283769">http://zenodo.org/record/4283769</a>
Acanthonotozomella barnardi Watling & Holman 1980
No full text<i>Acanthonotozomella barnardi</i> Watling & Holman, 1980 <p> <i>Acanthonotozomella barnardi</i> Watling & Holman, 1980: 612–614, figs 1–3.</p> <p> <i>Acanthonotozomella barnardi</i> – Watling & Thurston 1989: 303, 310, fig. 2d. — Coleman 2007: 15, fig. 1c–d, map 1 (circle).</p> Distribution <p>Off extreme southern Patagonia, 384–494 m (Watling & Holman 1980).</p>Published as part of <i>d'Acoz, Cédric d'Udekem & Verheye, Marie L., 2017, Epimeria of the Southern Ocean with notes on their relatives (Crustacea, Amphipoda, Eusiroidea), pp. 1-553 in European Journal of Taxonomy 359</i> on page 161, DOI: 10.5852/ejt.2017.359, <a href="http://zenodo.org/record/3855694">http://zenodo.org/record/3855694</a>
Model Representation & Decision-Making in an Ever-Changing World: The Role of Stochastic Process Models of Transportation Systems
No full textDay-to-day Dynamics & Equilibrium Stability in A Two-Mode Transport System with Responsive bus Operator Strategies
No full textModelling road traffic assignment as a day-to-day dynamic, deterministic process: a unified approach to discrete- and continuous-time models.
No full textWe consider the modelling of road transport systems as a day-to-day dynamic, deterministic process. The main contribution is to present a unified treatment of discrete-time and continuous-time approaches, with these two classes of approaches having been developed in two parallel streams of research which have had little connection made between them. In doing so, we aim to clarify the usefulness of these alternative approaches. We pay particular attention to: the specification of such models, the conditions which characterise the various forms of emergent behaviour, and the relationship between the model assumptions and real-world phenomena. The proposed framework is heavily focused, in the first instance, on a probabilistic approach to user choice modelling, though we also review and analyse the limiting case of deterministic choice model
Council cottages and community in inter-war Britain: a study of class, culture,politics and place.
No full textPhDThis thesis makes a contribution to the debates surrounding the idea of community
on the cottage council estates of inter-war Britain. It questions the conventional
wisdom that community was lacking upon these estates. Recognising the
problematic nature of the notion of community, this thesis overcomes the confusion
inherent in the term when it is used to describe social structures by viewing
community instead as a structure of meaning, as a discursive rather than material
reality. This guides my examination of community on the estates. Rather than
there being no community, it is argued that there were at least three different
discourses of community, and what is important is the relationships between them.
Chapter One discusses the contexts in which these estates were built, and then sets
out the ways in which community is understood in this thesis. Chapter Two
explains the methodology that was used, a combination of archival and oral histoiy.
In Chapter Three Roehampton and Watling - the two estates this research focuses
upon - are described in order to provide the contextual setting for my interpretation
of the discourses of community that were present there. Chapter Four is concerned
with community from the viewpoint of the residents who lived on the estates.
Chapter Five considers discourses of community from the point of view of the
tenants' and residents' associations that developed upon Roehampton and Watling.
Chapter Six explores the discourse of community that was promoted on the estates
by the Community Association movement.
Overall the thesis argues that the discourses of community on inter-war
housing estates have to be understood in terms of the occupational structures,
cultures and politics of these estates
Anthothela echinata Watling 2020, n. comb.
No full textAnthothela echinata (Kükenthal, 1915) n. comb. (Figs. 1–4) Muricellisis echinata Kükenthal, 1915, p. 124; Kükenthal, 1919, p. 627 Diagnosis. Colony membranaceous. Polyp cylindrical, often exsert or invaginated into calyx, crowded together with little coenenchyme space. Coenenchyme and calyx sclerites clubs, thorn-clubs, sticks and spindles; polyp sclerites sticks and spindles arranged as collaret and points. Tentacle sclerites short, flat tuberculate rods along the rachis with spatulate clubs in the pinnules. Pharyngeal sclerites not known. Type specimen. Museum für Naturkunde, Berlin, Germany Type locality. Sagami Bay, 730 m. Description. The type consists of three fragments totaling 11 cm according to Kükenthal (1919). The following description applies to an 8 cm piece loaned from the Museum für Naturkunde (Fig. 1a). The colony is membranaceous, overgrowing a piece of axis from a keratoisid bamboo coral (Fig. 2 e–g). Polyp calyces are very closely arranged with little coenenchyme space between them (Fig. 1b). The polyps are cylindrical, short, and mostly invaginated within the calyx, with the tentacles folded into the polyp (Fig. 1c, d). The polyp does not appear to have a typical cylindrical pharynx, rather there is a thick ring of tissue (“pharyngeal ring”) attached at the proximal end of the polyp as it invaginates into the calyx (Fig 1c, d, P). A few sclerites are visible under the tissue on the proximal (ventral) side of the pharyngeal ring (Fig. 2b, c). Short septa (S) extend proximally to the calyx wall from the pharyngeal ring and seem to spread across the interior of the calyx (Fig. 1c, d, Fig. 2d). In one case, eggs appear to be present along the inner calyx wall (Fig. 2a). The sclerites of the coenenchyme consists of sticks and small clubs (Fig. 3a). Most of the calyx sclerites are small clubs and thorn clubs of various sizes (Fig. 3b). The polyp sclerites are spindles in a collaret (?) and points arrangement. Flattened tuberculate rods are common on the tentacle rachis and small rods and spatulate clubs are found in the pinnules. Remarks. Kükenthal (1915, 1919) created the new genus Muricellisis for this species and added it to the Family Isididae as a new subfamily Muricellisidinae due to the presence of a calcareous axis with nodes and internodes underlying the polyps and coenenchyme. However, the curious form of the polyps and the spiny and tuberculate sclerites were unlike anything seen in the Isididae to that time. Kükenthal noted that had the calcareous axis not been present, he would have thought this species to be similar to Muriceides. The sclerites of this species, in particular the thorn-clubs of the calyx wall and spatulate clubs in the pinnules, suggests that the species belongs to the Anthothelidae. In addition, the documentation by Moore et al. (2017) that some members of the genus Anthothela could exist as membranous colonies with no axis cortex and medulla, hinted at the possibility that the keratoisidid axis present here could merely be a substrate on which the colony was growing. In fact, the form of the axis is definitely keratoisid-like, but also seems to be considerably degraded (images not shown). However, there are no members of the Keratoisidinae that have sclerites in the form possessed by this species. The most parsimonious explanation for the disparity between the form of the axis and the nature of the polyps and sclerites is that the octocoral and the axis on which it is growing do not belong to the same species. From the review of the Anthothelidae by Moore et al. (2017), there does not seem to be any known species in the genus Anthothela to which this species could belong. Several species have colonies with fully formed axes but as well are membranous growing on some unrelated substrate such as sponge spicules. Of the seven species of Anthothela, three have thorn clubs: in A. vickersi the thorn clubs are mostly rounded at the tips; those of A. aldersladei and A. tropicalis are most like those seen here in A. echinata. As with A. aldersladei, the thorn clubs are shorter (0.4–0.55 mm) than in A. tropicalis (0.33–0.78 mm). The calyces in A. aldersladei, however, are much taller than in A. echinata (1.5–2.5 mm in height vs. 1–1.5 mm, and 2–2.5 mm in width vs. 1.5–2 mm). Hockey stick sclerites were not observed in the few calyces and polyps of A. echinata that were examined. Their absence would further distinguish these two species.Published as part of Watling, Les, 2020, Toward a revision of the bamboo corals: Part 1, species in the Muricellisidinae (Octocorallia: Isididae), pp. 361-371 in Zootaxa 4881 (2) on pages 362-367, DOI: 10.11646/zootaxa.4881.2.9, http://zenodo.org/record/428376
Magelona anuheone Magalhães & Bailey-Brock & Watling 2018, sp. nov.
No full text<i>Magelona anuheone</i> sp. nov. <p>Figures 7 (D‒F) and 8</p> <p> <b>Material examined</b>. Holotype: Easter Island, Hanga Roa, 27°08'45.60" S, 109°26'06.00" W, Sta. HB3, 5 November 2015, coll. L. Watling (USNM 1494162). Paratypes: Easter Island, same date and collector as holotype: Vare Vare, Sta. Bajo B4 (1 af, USNM 1494163); Vare Vare, Sta. Ariba A3 (4 af, SCBUCN-7281; 1 af, MNHNCL ANN-15018; 1 af, MNHNCL ANN-15019; 1 af, MNHNCL ANN-15020). Additional material examined. Hanga Roa, Sta. HB3 (1 af); Sta. Ariba A1 (1 af); Vare Vare, Sta. Ariba 1 (1 af); Sta. Ariba 2 (1 af); Sta. Ariba 3 (1); Ariba 4 (6 af and 1 pf); Sta. Ariba 5 (3 af); Sta. Bajo B1 (3 af); Sta. Bajo B2 (3 af); Sta. Bajo B3 (2 af); Sta. Bajo B5 (4 af and 1 pf).</p> <p> <b>Diagnosis.</b> Prostomium much longer than wide, with distinct prostomial horns. Notopodia of chaetigers 1‒8 with elongate postchaetal lamellae with minutely crenulate upper edges. Low, rounded pre-chaetal lamellae. Superior processes present from chaetigers 1‒8. Thoracic chaetae simple bilimbate capillaries. Abdominal hooded hooks tridentate. Lateral pouches (Ʃ configuration) present between chaetigers nine and ten.</p> <p> <b>Description.</b> Holotype: incomplete posteriorly; prostomium 1.84 mm long, 1.14 mm wide; thorax 8.3 mm long (including prostomium), 0.61 mm wide; abdomen 0.79 mm wide; total length 26.4 mm for 45 chaetigers. Four paratypes measured, all posteriorly incomplete; prostomium 0.84‒1.05 mm long, 0.63‒0.8 mm wide; thorax 3.97‒5.3 mm long (including prostomium), 0.36‒0.43 mm wide; abdomen 0.35‒0.45 mm wide; total length 13.4‒24.5 mm for 31‒61 chaetigers.</p> <p>Prostomium much longer than wide (L:W ratio 1.25‒1.61), rounded laterally; anterior margin smooth, rounded triangular, with conspicuous prostomial horns, bulbous; horns distinctly separated from antero-lateral margins of prostomium (Figs 7D; 8A, B). Two pairs of prominent, thick longitudinal dorsal ridges; outer pair, reaching further basally and approaching achaetous segment and with transverse rings; inner pair diverging anteriorly into horn corners and posteriorly towards prostomial base, medially fused along their length (Fig. 8A). Burrowing organ partially everted in several specimens including holotype and paratypes, oval with distinct ridges (Fig. 8A). Holotype with both palps attached. Palps arising ventro-laterally from base of prostomium, short, marginally longer than thoracic region (Fig. 8A); palps measuring 5.52‒5.78 mm long; non‒papillated region short reaching as far as chaetiger 3 (Fig. 8A). Papillae short proximally but long for majority of length, digitiform; proximally and medially with eight rows of papillae reducing to four rows distally. Achaetous segment slightly longer than chaetiger 1 (Fig. 8A).</p> <p>Thoracic segments longer than wide; chaetigers 1‒8 similar; parapodia biramous; notopodia with low rounded prechaetal lamellae confluent with elongate postchaetal lamellae with rounded tips of similar size throughout thorax (Fig. 8E‒H); notopodial lamellae minutely crenulated (Fig. 8E‒G). Digitiform prechaetal superior processes present (DML), digitiform. Neuropodial pre- and postchaetal lamellae as low ridges; ventral lobes (VNL) lobes digitiform anteriorly, becoming triangular on posterior thoracic segments (Fig. 8E‒H). Chaetigers nine and ten short. Chaetiger 9 (Fig. 8H): notopodial prechaetal lamellae rounded, postchaetal lamellae slightly shorter than preceding thoracic chaetigers, triangular; superior processes (DML) absent. Neuropodia of chaetiger nine similar to chaetiger eight (Fig. 8G, H). Chaetae of all thoracic chaetigers simple bilimbate capillaries (Fig. 8C); number of capillaries increasing towards posterior thorax, 10‒18 notopodial capillaries initially, increasing up to 24 on chaetiger nine; 6‒10 increasing to up to 18 in the neuropodia.</p> <p> Anterior 6‒8 abdominal segments as long as wide and becoming longer posteriorly. Abdominal parapodia with elongate lateral lamellae (Fig. 8I, J), well-developed postchaetal extension of lateral lamellae behind chaetal rows in anterior abdomen; DML and VML present, distinct, long. Abdominal chaetae tridentate hooded hooks of similar size throughout, long; two same-sized teeth above main fang (Fig. 8D); a pair of internal arcuate chaetae present <i>sensu</i> Fiege <i>et al.</i> (2000) present (Fig. 8I). Hooks in two groups, main fangs <i>vis–à–vis</i>; groups with same number of hooks and all hooks of similar size (Fig. 8I, J). Anterior abdominal segments with 4‒6 hooks per ramus, reducing to 3‒5 in posterior abdominal segments. One smaller tridentate hook present at the bases of lateral lamellae (Fig. 8I).</p> <p>Anterior lateral pouches (Σ configuration) present between chaetigers 9 and 10, paired (Fig. 8A); simple (C configuration) pouches not observed. Round patch of glandular structures darker than body present throughout abdominal region but more evident on anterior 8‒10 chaetigers.</p> <p>Pygidium observed on one posterior fragment (presumed to be same species), rounded with a pair of digitiform, lateral anal cirri (Fig. 8K).</p> <p>All preserved specimens lacking pigmentation, pale yellow.</p> <p> <b>Methyl Green Staining.</b> Anterior and median region of prostomium unstained (Fig. 7E). Proximal prostomial region, achaetous segment and thoracic region stained with a uniform green; abdominal segments staining slightly darker than thoracic ones. Dorsal transverse bands present from chaetigers 3‒7 just posterior to parapodia (Fig. 7E). Mid-ventral region of thorax with green speckles along longitudinal lines (Fig. 7F).</p> <p> <b>Reproduction.</b> Holotype an ovigerous female with eggs present in body cavity. Eggs densely packed from chaetiger 48. Eggs become larger along the body reaching about 65 µm in diameter from chaetiger 55.</p> <p> <b>Remarks.</b> <i>Magelona anuheone</i> sp. nov., belongs to a small group of five species (<i>M. berkeleyi</i>, <i>M. cornuta</i>, <i>M. montera</i> Mortimer, Cassà, Martin & Gil, 2012, <i>M. nonatoi</i> Bolívar & Lana, 1986, and <i>M. tehuanensis</i> Hernandez- Alcantra & Solis-Weiss, 2000) all sharing the following characters: 1) prostomium with frontal horns; 2) distally crenulate notopodial lateral lamellae; 3) chaetiger nine possessing only winged capillaries, and 4) tridentate abdominal hooks. <i>Magelona berkeleyi</i> and <i>M. nonatoi</i> have rudimentary prostomial horns whereas the new species, <i>M. montera, M. tehuanensis</i>, and <i>M. cornuta</i> have well-developed frontal horns. <i>Magelona cornuta</i> and <i>M. tehuanensis</i> have a crenulated margin of the prostomium and the new species <i>M. anuheone</i> sp. nov. and <i>Magelona montera</i> have a smooth margin of the prostomium and distinct bulbous horns.</p> <p> <i>Magelona anuheone</i> sp. nov. shares many similarities with <i>M. montera</i> from the Red Sea especially on the prostomial characteristics and methyl green staining pattern, both species having unique prostomial horns with bulbous distal tips (Mortimer <i>et al.</i> 2012). It differs most noticeably on the shape of the abdominal parapodial chaetal lobes and presence of anteriorly opening lateral pouches in between chaetigers 9 and 10.</p> <p> Although several species have been described with anteriorly open pouches, only <i>M. parochilis</i> Zhou & Mortimer, 2013 also lack modified chaetae on chaetiger 9. It differs from <i>M. anuheone</i> sp. nov. on the segmental origin of the open pouches (in between chaetigers 9/ 10 in <i>M. anuheone</i> and chaetiger 11/ 12 in <i>M. parochilis</i>), and by having a rounded prostomium without prostomial horns.</p> <p> <b>Etymology.</b> The new species epithet derives from the Rapa Nui language and is a combination of <i>anuhe</i> (caterpillar) and <i>one</i> (sand). The implied meaning being ‘caterpillar of the sand’ and the new name was chosen by Sergio Rapu from Rapa Nui (Easter Island).</p> <p> <b>Distribution.</b> This species is only known from shallow waters of Easter Island, Southeastern Pacific Ocean.</p>Published as part of <i>Magalhães, Wagner F., Bailey-Brock, Julie & Watling, Les, 2018, Four new species of Magelona (Annelida: Magelonidae) from Easter Island, Guam and Hawaii, pp. 379-396 in Zootaxa 4457 (3)</i> on pages 391-394, DOI: 10.11646/zootaxa.4457.3.2, <a href="http://zenodo.org/record/1457879">http://zenodo.org/record/1457879</a>
Enhanced velocity overshoot and transconductance in Si/Si(0.64)Ge(0.36)/Si pMOSFETs - predictions for deep submicron devices
No full textNo abstract avaliable
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