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FIGURE 4. a–c. Stephanometra indica. d–f. Lamprometra palmata. a, d. Ray base with brachitaxes IBr2 and IIBr2. b, e. Centrodorsal aboral view. c, f in A revision of the comatulid genus Stephanometra AH Clark with a rediagnosis of the genus Lamprometra AH Clark (Echinodermata: Crinoidea)
No full textFIGURE 4. a–c. Stephanometra indica. d–f. Lamprometra palmata. a, d. Ray base with brachitaxes IBr2 and IIBr2. b, e. Centrodorsal aboral view. c, f. Centrodorsal lateral view. Scale bars: upper left (a, d), upper right (b, c), lower right (e, f), all 2 mm.Published as part of Rankin, Dana L. & Messing, Charles G., 2008, A revision of the comatulid genus Stephanometra AH Clark with a rediagnosis of the genus Lamprometra AH Clark (Echinodermata: Crinoidea), pp. 1-35 in Zootaxa 1888 on page 9, DOI: 10.5281/zenodo.18429
Kinetic studies of mullite synthesis from alumina nanoparticles and a preceramic polymer
No full textThe crystallization kinetics of mullite formation in a diphasic precursor consisting of a silicone resin filled with commercial γ-alumina nanoparticles (15 nm mean particle size, specific surface area of 100 m 2/g), heated in air from 1250° to 1350°C, was studied by X-ray diffraction. Transitional γ-alumina and amorphous silica from the pyrolysis of the preceramic polymer exhibited a remarkable reactivity, as demonstrated by a very low incubation time (from 500 s at 1250°C to 20 s at 1350°C), a high mullite yield (about 80 vol%, after 100 s at 1350°C), and a low activation energy for nucleation (677±60 kJ/mol). The activation energy values found were lower than those reported previously for other diphasic systems, including sol-gel precursors. Besides the high specific surface of nanosized γ-alumina particles, the low energy barrier could be attributed to the highly reactive silica deriving from the oxidation of Si-CH3 bonds in the silicone and to the homogeneous dispersion of the nanosized filler inside the preceramic polymer. Furthermore, the possibility of applying plastic shaping processing methods to the mixture of a preceramic polymer and nanosized filler makes this approach particularly valuable, in comparison, for instance, with sol-gel based alternatives
Atopocrinus ojii Messing 2020, new species
No full textAtopocrinus ojii new species Table 1, figures 4–11, 12B–F Material examined. E of Miyakejima, Izu Is., Japan: OMNH cat. no. Iv2233, R / V Soyo, 34°31.8’N, 140°17.1’E, 1160 m, trawl, 14 Nov 1972, T. Okutani, coll. (holotype); OMNH cat. no. Iv2448, R / V Soyo, 34°03.0’N, 140°02.0’E, 1210–1235 m, trawl, 5 Jul 1967, T. Okutani, coll. (1, paratype); OMNH cat. no. Iv2980, R / V Soyo, 34°03.4’N, 140°04.7’E, 1270 m, trawl, 29 Jun 1969 (1, paratype). E of Chiba Prefecture, Japan: SAM cat. no. K2158, 35°09’N, 140°52’E, 522–537 m (Ext. no. C040), 24 Jun 2001, T. Oji, coll. (1, paratype). USNM cat. no. 1548291, R / V Tansei- Maru, Univ. Tokyo, cruise no. KT-01-8, sta. TK-1-5, 35°08.795’N, 140°51.061’E to 35°09.545’N, 140°51.933’E, 512–529 m, 3-m ORI beam trawl, 22 Jun 2001 (1, paratype, partly dissociated for SEM). Diagnosis. Atopocrinus with centrodorsal as tall as wide at base, or taller, and with small apical opening into centrodorsal cavity; HW 1.0–1.3. Cirrus sockets round or slightly oval, more deeply concave than in A. sibogae, in three columns per radial area proximally and two columns apically in large specimens; two columns per radial area in a smaller specimen. Deep “pore” between many or all fully developed sockets of a column; “pores” sometimes large enough so that sockets appear as short cylinders ‘attached’ to each other or the adjacent interradial ridge only at intervals around their circumferences. Interradial ridge sometimes crossed by distinct suture immediately aboral to suture between basal and centrodorsal as in A. sibogae, and often with 1 to 4 additional faint suture-like lines. Synarthrial tubercle on IBr2 moderately to strongly developed, with proximal angle in aboral view>90°; profile of arm base rounded or with distinct angle. Alternating articular tubercles on following proximal brachials weak to moderate. Description of holotype (OMNH Iv2233) (Figures 4, 5, 12C).—Centrodorsal conical with straight sides. Interradial ridges along entire length of centrodorsal, stronger basally. Three of five ridges crossed by distinct suture immediately aboral to suture between basal and centrodorsal (Figure 4 B–D). Cirrus sockets in two lateral columns per radial area, of 6 sockets each; third, midradial column of 3 sockets (2 in one radial area) in basal half of each radial area; basalmost socket of several columns not fully developed; total number of functional sockets in Table 1 omitting one much smaller rudimentary cirrus at centrodorsal base in three radial areas; apicalmost socket in several columns obsolete. Exterior ends of basals triangular or pentagonal, not of equal sizes; three crossed by fracture or suture-like line distinct from apparent suture with centrodorsal interradial ridge (Figure 4D). Externally visible portion of radials extremely short and broadly U-shaped when specimen viewed from side (Figure 4A), with diverging lateral margins and straight distal margin in aboral view; lateral margins of articulation with succeeding br1 parallel to oral-aboral axis (Figure 4A, D). Arms retained to br5, br7, br10, br14, and br20. Br1 rectangular, not in contact laterally, with small lateral rounded triangular projections wider distally; distal margin straight or shallowly V-shaped. Br2 irregularly quadrate, with lateral margins diverging, one short and one long. Brr3 and 6 almost triangular. Brr4+5 and 7+8 strongly wedge-shaped, with long lateral margin on opposite side of arm from long lateral margin of preceding br. Brr9 and 10+11 slightly wedge-shaped. Brr7+8 and 10+11 with WL 1.7. Brr12 and 13 rectangular or slightly wedge-shaped, WL 2.5–2.8. Br14+15 and br16 wedge-shaped. Brr17–19 almost triangular. Brr16–19 with WL 2.0–2.2. First three syzygies (brr4+5, 7+8 and 14+15) similar to those of A. sibogae, with only five narrow, widely separated radiating ridges. Succeeding syzygies (brr14+15, 20+21) with numerous fine, crowded ridges. Pinnules arise from short lateral margin of brr2–9 (no pinnule on brr4 and 7—proximal ossicles of syzygial pairs), and from longer lateral margin on succeeding brachials (Figure 5). Pinnular articulations for P1–3 and Pa–b project at an angle from lateral margin of brachials (brr2–8) (Figure 5A); articulations for succeeding pinnules flush with lateral margin of brachials (Figure 5B). P1 on left side of br2 on 4 arms and on right side of 1 arm. P2 absent on br5 of one arm. Remaining portion of P1 20 mm long, of 13 pinnulars (missing tip of unknown length); pinnulars longer than wide and smooth, increasing irregularly in length from P1 (1) (LW 1.4) through proximal third of pinnule length; LW of longest proximal pinnular 2.5–3.2; following pinnulars decreasing in length; distal pinnulars with LW 2.0; distalmost 3 remaining pinnulars shorter and with weak spines. Proximal pinnulars oval in cross section, attached to visceral mass to about P1 (5) and lacking ambulacral furrow; following pinnulars developing ambulacral furrow, becoming more pronounced on distal pinnulars. P2 similar, but P2 (1) with LW 1.0; pinnulars with greatest LW in proximal third. P3 broader basally than preceding; P3 (1) half-moon-shaped, wider than long; P3 (2) trapezoidal, narrower distally and as wide as long; middle pinnulars proportionately longest. Following pinnules all broken; second pinnular becoming wider than long; middle pinnulars weakly carinate, slightly expanded distally, with LW 1.0–1.3. Disk mostly hidden within arm bases; anal papilla reaching level of br13; lateral surface of tegmen visible between adjacent arm bases with numerous small, more or less rhombic plates, forming pavement to level of brr2–3 and becoming more scattered and irregular, but submerged in tegmen tissue adorally, so that shapes are difficult to observe. Description of large paratype (OMNH Iv 2448) (Figures 6A, C, 12D).—Similar to holotype but with centrodorsal as wide basally as tall, with midradial column of cirrus sockets reaching more than halfway to centrodorsal apex. One interradial ridge crossed by a distinct suture immediately aboral to suture between basal and centrodorsal (and a similar but partial suture in another ridge—both may be fractures in their respective basal ossicles). All five interradial ridges crossed by four additional faint suture-like lines (Figure 6C). Cirrus sockets as in holotype but with 5–6 sockets in each lateral column and 2–4 in midradial column, again with one basalmost lateral socket not fully developed, and with one rudimentary cirrus at base of midradial column in each radial area. Aboral corners of radials swollen against ends of basals. Arms retained to br7 (3) and br10 (2). P1 on left side of br2 on 3 arms; on right side on 2 arms. All remaining pinnules incomplete (P1 retaining at most 11 segments). Description of small paratype (OMNH Iv 2980) (Figures 6B, D, 12B).—Small specimen with 2 columns of 4 cirrus sockets plus one midradial rudimentary cirrus in each radial area; basalmost socket in one column in each radial area not fully developed (4 left, 1 right when viewed with apex downward). Interradial ridges of centrodorsal crossed by 3–5 faint suture-like lines aboral to centrodorsal/basal suture (Figure 6D). (The basalmost of these may be equivalent to the supposed suture between A. H. Clark’s “reduced basal” and centrodorsal in A. sibogae.) Centrodorsal apex with round opening. External ends of basals pentagonal. Aboral corners of radials not swollen against ends of basals. Ray ossicles proportionately more elongated than in larger specimens, but still all wider than long. Arms retained to br10 (1) and br7 (4). P1 on left side of br2 on all arms. Most pinnules incomplete; longest pinnulars proportionally longer than in larger specimens; LW to 3.6. P3 missing only distal tip, of 10 segments, 5.6 mm long. Description of paratype (SAM K2158) (Figures 7, 12F).—Centrodorsal conical, taller than wide at base; sides straight, or slightly convex in proximal half; apical third slightly bent to one side. Interradial ridges along entire length of centrodorsal, stronger basally, each crossed by 1–2 faint apparent suture lines just aboral to suture between basal and centrodorsal. Tip of apex severed, exposing small cone of tissue. Cirrus sockets in two lateral columns per radial area, chiefly of 10 sockets each, with third, midradial column of 5–6 sockets reaching more than halfway to apex in each radial area. Pores between sockets fewer and smaller than those in other specimens. No fully developed cirri retained; small immature cirrus at base of four radial areas. Exterior ends of basals roughly pentagonal, forming adoral extensions of centrodorsal interradial ridges. Sides of basals partly visible but disappearing into deep, low subradial clefts between centrodorsal margin and exterior surface of radials. Externally visible portion of radials short, with diverging lateral margins; proximal corners slightly swollen over ends of basals; distal margin shallowly U-shaped in side view of specimen, almost straight in aboral view; distinct small “pore” between distolateral corners of adjacent radials. Arms retained to br5 (2), br7 (2), and br10. Br1 rectangular, not in contact laterally; lateral margins straight and slightly projecting laterally in aboral view; lateral projections hemispherical in side view of arm; distal margin shallowly V-shaped. Br2 irregularly pentagonal, with lateral margins diverging; left short, right long. Synarthrial swelling between br1 and br2 well developed, midaboral, narrow. Br3 almost triangular, narrowing to right side. Br4+5 wedge-shaped, narrowest across syzygial articulation. Br6 short, wedge-shaped. Br7+8 not as strongly wedgeshaped as br4+5. Br9 almost oblong. Alternating articular swellings diminishing from brr3–4 through several following non-syzygial brachial pairs; negligible by brr8–9. All remaining pinnules incomplete. P1 arising from left side of br2, longest remaining of 11 pinnulars, 19 mm long (missing tip); pinnulars compressed, longer than wide. LW of proximal pinnulars: P1 (1) 1.2, P1 (2) 2.3, P1 (3) 2.8, and P1 (4) 2.9; following pinnulars gradually shorter and more slender, but P1 (5) more elongated, LW 3.1. Abambulacral lateral margin of second through fourth pinnulars gently convex. P2 with pinnulars shorter and less elongated than in P1; LW of selected pinnulars: P2 (1) 1.6, P2 (2) 1.9, P2 (3) 1.8, P2 (7) 2.6, P2 (8) 2.5. Sides of disk narrowly visible between proximal arms, with numerous small round calcareous plates. Oral surface of tegmen mostly mutilated. Proximal portions of each proximal pinnule connected to tegmen by thin sheet of tissue. Anal papilla with no visible plates. Paratype partly dissociated for scanning electron microscopy (USNM cat. no. 1548291) (Figures 8 –11, 10, D, F, G, 11E). Similar to holotype and large paratype but with sockets more crowded and numerous, inter-socket “pores” smaller, and no visible apical pore (after coating for SEM) (Figure 8A, D). Adoral surface of centrodorsal with 5-rayed, stellate, thin-walled depression surrounding central cavity; depression rays narrow, interradial, reaching exterior, broader toward outer and inner ends; outer ends of rays truncated or rounded (Figure 8B). One ray floored by three layers forming shallow steps rising toward central cavity (uppermost ray in Figure 8B). Each radial area of adoral centrodorsal surface with 1–2 tube-shaped rudimentary sockets not reaching exterior margin. Fully developed basalmost sockets also visible as tubes on adoral surface. Centrodorsal apex with one apparently obsolete socket in 2 radial areas. Interior of centrodorsal cavity with five broad interradial buttresses crossed by numerous regular fine ladder-like ridges and grooves (Figure 8C); adoral opening ~0.25x basal diameter. No suture-like lines visible on interradial ridges (Figure 8D). (Note: specimen not examined for this feature before dissociation for SEM.) Basals tongue-shaped, with no rosette; interior end of each basal wider, with two short, oblique, truncated projections, each abutting the projection of the neighboring basal; adoral surface convex; aboral surface flat or slightly concave, partially bordered by narrow ridge (Figure 9 A–B). Radial articular facet deeply excavated, wider than tall (Figure 9 C–E). Aboral ligament fossa 4x wider than high, with wide, deep ligament pit. Central lumen surrounded by coarse stereom forming a tube with two low triangular “wings” extending laterally to ends of fulcral ridge. Muscle fossae parallel to oral-aboral axis, thin-walled, roughly triangular with rounded adoral and lateral corners (mostly broken), and separated medially by low narrow ridge of coarse stereom. Lateral ends of muscle fossae extending beyond ends of fulcral ridge. Weak ridge separating long narrow interarticular ligament fossae from muscle fossae, but with stereom similarly labyrinthic on both sides of ridge (Figure 9C). Muscle fossae with surface layer of fine stereom with weak concentric lines, eroded in places in examined ossicles, revealing coarser underlying stereom lacking concentric features. Interior surface of radial ossicles with two pairs of canal openings (Figure 9F). Lateral surfaces with a strong knobbed ridge running outward from just adoral of the outer canal openings to just short of the lateral ends of the muscle fossae (Figure 9F). Aboral face flat; lateral-aboral margins excavated to accommodate basals (Figure 9G). Synarthry between br1 and br2 with adambulacral portion of fulcral ridge short, less than half length of abambulacral portion. Ligament fossae roughly triangular, restricted to abambulacral half of facet (Figure 10A). Muscle fossae on proximal brachials large, roughly triangular, separated from each other by narrow ridge of coarse stereom, and separated from interarticular ligament fossae by weak ridge (Figure 10C, D). Stereom of muscle fossae and interarticular ligament fossae similar. Middle brachials with distal border of spines (Figure 10G, H). Pinnule articulations large, deeply excavated, with one muscle fossa (Figure 10C, D, G, H). Proximal three syzygies with five widely spaced ridges; two lateral ridges L- or ˩-shaped, each with the short arm oriented toward ambulacrum; ridge surfaces consisting of fine, closely crowded and often fused, concentrically-oriented solid stereom ridges; articular area of syzygy occupying about two-thirds of ossicle facet (Figure 10B). Syzygies beyond 14+15 with numerous narrow ridges; several ridges very short and almost none reaching large central lumen; articular area occupying almost entire ossicle facet (Figure 10I). Detached mid-arm fragment of 23 wedge-shaped to almost triangular brachials, wider distally with finely spinose distal margins, WL 1.4–1.6. Intersyzygial interval 3–5. Exterior surface of brachials crossed by irregular, extremely fine “ledges”, each with a row of fine, distallydirected recumbent spines projecting slightly beyond the ledge edge, with rows of stereom pores between generally diminishing in size toward ledge (Figure 10E, F). Complete P1, 16 mm long, of 13 pinnulars, the distal 6 regenerating, short, with distal margins finely spinose. Description of pinnule articulations dissociated for scanning electron microscopy (holotype OMNH Iv2233 and paratype USNM cat. no. 1548291) (Figure 11). P1 (1) with distal articulation roughly symmetrical with paired muscle fossae deeply excavated and almost fused (Figure 11A). P2 (1) with proximal articulation asymmetrical, with lumen and adjacent shallow ligament pit strongly offset from facet center; one arm of fulcral ridge much shorter than the other; single deep muscle fossa adjacent to lumen but recessed on adambulacral surface of ossicle (Figure 11B). Long proximal pinnulars of P2 with most of facet relatively flat with large abambulacral ligament fossa; distal facet with asymmetrical fulcral ridge and single deep muscle fossa slightly offset adjacent to lumen (Figure 11C); proximal facet with roughly symmetrical fulcral ridge and paired muscle fossae deeply recessed along adambulacral margin (Figure 11D, right end). Pinnulars hollow (Figure 11E). More distal pinnulars gradually developing deep V-shaped ambulacral groove (Figure 11F, H–I); lumen offset from facet center with short fulcral ridge restricted to side of facet opposite ambulacral groove; single deep muscle fossa on same side of groove as lumen and fulcral ridge (Figure 11H, I). Distal pinnulars with numerous long recumbent spines on one side and fine diagonal ridges similar to those of brachials (Figure 10E, F) on the other (Figure 11G). Etymology. Named for Tatsuo Oji, Professor, Department of Earth and Planetary Sciences, Nagoya University, Nagoya, Japan, for his many contributions to our understanding of both living and fossil Crinoidea. Distribution. Known only off eastern Japan in 529 (possibly 512) to 1270 m. Remarks. The differences between similarly-sized specimens of A. sibogae and Atopocrinus ojii n. sp. appear significant and consistent enough to warrant recognition of the latter as a distinct species. Atopocrinus ojii n. sp. has three rather than two columns of sockets per radial area, round rather than squarish cirrus sockets, and centrodorsal with an apical pore, and pores between cirrus sockets. Figure 12 illustrates the centrodorsals of all specimens of both species, and figure 13 illustrates how cirrus number relative to centrodorsal height distinguishes the two. Whether the two species differ or not in several other characters, e.g., presence or absence of a rosette, overall shape of basals, and structure of the adoral surface of the centrodorsal and its interior buttresses, cannot be determined at present, because A. sibogae remains known from a single specimen. The inter-socket pores of Atopocrinus ojii n. sp. appear to be unique among extant crinoids. However, it could not be determined whether they communicate with the centrodorsal cavity or end blindly, possibly as pouches within the interradial buttresses inside the centrodorsal. Four of the five specimens of A. ojii also have a pore in the centrodorsal apex. Gentle insertion of a fine needle in the two largest specimens met no resistance and suggests that the pore communicates with the centrodorsal cavity. A similar, although five-rayed, perforation corresponding to the central stalk canal remains at the aboral apex of the centrodorsal in feather stars following separation from the postlarval stalk (Mortensen 1920, p. 30) but becomes plugged by stereom shortly thereafter. However, Mortensen (1918) noted that the pore remains in a half-grown specimen of Notocrinus virilis Mortensen, 1917. Other species, including several fossil genera, retain a five-rayed depression at the aboral pole—the so-called dorsal star—although it is unknown how long any communication with the centrodorsal cavity remains after separation from the postlarval stalk in these taxa: e.g., Glenotremites, Loriolometra, Remesimetra (all Notocrinidae), Kiimetra miocenica Shiibata & Oji, 2007 (Calometridae) (Hess & Messing 2011). In the single dissociated specimen of Atopocrinus ojii n. sp., the tongue-like basals lack a rosette. Messing & White (2001), described the zenometrid genera Zenometra and Sarametra as lacking a rosette as well. However, unlike Atopocrinus ojii n. sp., the inner end of each basal in both zenometrid genera ends abruptly and bears a pair of concavities, which appear to be partial versions of two openings in confamilial Psathyrometra. The openings in the latter are continuations of the aboral nerve canals of the overlying radials and correspond to the interradial and radial processes of the rosette of antedonids. The lack of similar structure in Zenometra and Sarametra may derive from poor preservation (Messing & White 2001). Although a rosette as a discrete, centrally perforated, decagonal plate does not appear to exist in any of these genera, the inner ends of their basals exhibit structure not found in Atopocrinus ojii n. sp. The centrodorsal of A. ojii n. sp. bears a striking resemblance to that of Spinimetra chesnieri Hess & Thuy, 2017, from the Lower Jurassic (Toarcian, Tenuicostatum Zone). Both share the following features: conical centrodorsal with small apical opening and pores between cirrus sockets; aboral surface of centrodorsal with tube-shaped rudimentary sockets flanking narrow basals, and cirrus sockets with a pronounced horseshoe-shaped rim, each a blunt triangle projecting outward and downward. (Compare Figure 8D with 14A, and 8C with 14B.) The combination exists in no other crinoids, extant or fossil, although two characters occur separately elsewhere: horseshoeshaped socket rims in Atelecrinidae and an apical pore in Notocrinidae, mentioned above. Spinimetra differs from Atopocrinus in lacking the interradial ridges on the centrodorsal, and in having basals with marginal crenulae. In addition, the centrodorsal of S. chesnieri appears to be constructed of multiple “nodals”; juvenile specimens of S. chesnieri suggested to Hess & Thuy (2017) that its centrodorsal was constructed of a stack of separate ossicles. It is tantalizing to consider the possibility that the faint suture-like lines that cross the interradial ridges in A. ojii n. sp. (Figures 2, 4, 6) might represent a vestige of this multi-ossicle construction (although the dissociated specimen of A. ojii exhibited no suture-like lines). As the cirrus sockets in this species develop as tubes adjacent to the centrodorsal base, it is not surprising that the faint suture-like lines do not cross them. Nevertheless, the characters that the two genera have in common may be convergences rather than homologies. As S. chesnieri is known only from centrodorsals, no further comparison wi
Porphyrocrinus daniellalevyae Messing, 2016, new species
No full textPorphyrocrinus daniellalevyae new species Etymology. Porphyrocrinus daniellalevyae n. sp. is named in honor of Daniella Levy Becker by Robert Becker in recognition of their generous support for research on crinoids at Nova Southeastern University. Material. USNM 1411123 (holotype) Johnson Sea-Link II 3698, West of Little Bahama Bank, 27º04.0652'N, 79º19.2923'W, 582 m, 29 July 2009. USNM 1411124 (large paratype) and MNHN-IE-2014-2001 (small paratype) (both partly dissociated for SEM), Johnson Sea-Link II 3685, West of Little Bahama Bank, 27º04.499’N, 79º19.200’W, 616 m, 23 July 2009. UMML 44.239 (paratype, crown only), R/ V Suncoaster, dredge #3, S of Bimini, Bahamas, 25º28.477’N, 79º17.632’W, 400 m, 23 May 2002, A. Oleinik, coll. Diagnosis. A species of Porphyrocrinus with at least eight and up to at least 17 radials, the number probably increasing with size. Stalk to at least 408 mm long; proxistele of 7–11 thin, disk-like columnals; no articulations with multiradial facets; dististele short (11 columnals in single specimen with complete stalk); ratio of major to minor columnal diameter (D/d) to 1.4 distally. Aboral cup as wide distally as tall (small specimen) to wider than tall; basals squarish or taller than wide; radials taller than wide. Rays unbranched; arms to at least 73 mm long, with distal apinnulate filament; maximum arm width at Br4–6; proximal arm articulation pattern chiefly 1+2 3+4 5+6 with first pinnule on left side of Br6 but with several variations. First 4–5 pinnules on both sides of arm genital; gonadal expansion covered with thin interlocking plates; ambulacral tissue of middle and distal pinnules with numerous small fine single and irregularly branched needles, and few small coarse meshes. Disk interambulacral areas at least partly covered with thin, polygonal interlocking plates. Description of holotype (Figures 1 A–C, 2, 3A–B, 4A, 5, 6B-C; Tables 1, 2). Total stalk L= 408 mm including attachment disk, of 124 columnals; attachment disk thick and truncated (Figure 2). Proxistele of proximalmost 11 visible columnals with tight sutures difficult to distinguish (Figure 4 A). Mesistele (C12–C113) accounting for great majority of stalk length; weak synarthrial gap visible externally between C11–12, but D/d>1.0 at C13–14 (1.02, 1.08); pairs of columnals developing barrel-shaped profile across major diameter (D) by C14–15. Mesisteledististele transition at C113–114, corresponding to increase in D from 4.3 mm (C111) to 4.5 mm (C114). Stalk diameter (D) (Table 1): C1 same as base of adjacent basal ring; gradually decreasing to C13–14; increasing gradually from C15 to 3.8 mm by mid-stalk, and 5.5 mm immediately above attachment disk (Figure 3 A). Columnal height: C1–7 thin, discoidal, 0.2–0.3 mm tall; gradually increasing in height to C81 (4.5 mm), remaining about the same to C100, and diminishing irregularly to just above base (2.6 mm). Columnal HD ratio: similar for C1–6 (0.11–0.14), gradually increasing and reaching 1.0 by C32; remaining similar from ~C53 to C92 (1.07–1.15), then gradually decreasing, especially following C108 (0.90), through mesistele-dististele transition (0.85), to 0.69 (C120) and 0.50 (C123) (omitting abnormal C121 and 124) (Figure 3 B). Slight dip in HD ratios (Figure 3 B, large arrow) due to slight but abrupt increase in columnal diameter from 1.8 (C17) to 2.3 (C21) with little increase in ossicle height. C112 and 113 each shorter and narrower than C111 or C114, joined by tightly anchylosed articulation (Figure 2, upper arrow); C121 longer and narrower than C120 or C122 (Figure 2, lower arrow; 3A and B, small arrows), with slightly constricted, apparently rudimentary anchylosis (i.e., possibly two ossicles) (see under USNM 1411124 for descriptions of facets of articulations with similar exterior appearance); distalmost columnal (C124) above attachment disk much shorter and narrower than those above it. Aboral cup (basal+radial rings) wider adorally than tall. Basal ring almost cylindrical; diameter slightly greater adorally; sutures indistinct (Figure 4 A). Radial ring a short, inverted, truncated cone of 15 radials. Profiles of radial and basal rings creating an angle of 140–150º. Individual radial ossicles straight sided, slightly wider distally; aboral surface gently convex. Radials shorter than basals. Rays 73 mm long, including remaining ~17-mm apinnulate terminal filament (Figure 1 C). IBr1 squarish, laterally apposed, slightly wider distally; joined to radial by muscular synarthry. IBr2 similar but wider, with weak thin lateral flange; WH 1.2–1.3. IBr3 to IBr6–8 gradually wider and shorter with more strongly developed flange; WH increasing from 1.5 to 1.8. Following brachials more strongly rounded, with plane of thin lateral margins oriented toward interior of crown. Middle brachials shorter, wider distally, with distal margin slightly raised; free middle brachials becoming squarish through middle of arm; proximal ossicle of a brachial pair higher, with convex distal margin and WH 1.9; distal brachial of a pair shorter, with straight distal margin and WH 1.4. Distal brachials narrower with slightly expanded distal ends, becoming higher than wide, but no higher than shorter middle brachials; WH 0.8–0.9. Arms terminating in delicate threadlike filament up to 30 mm long (none remaining complete) (Figures 1 B, C). Aboral and lateral surfaces of brachials covered with crowded, distally-directed recumbent spines; spines becoming more erect but still distally-directed on distal brachials (see Figures 15 E–F, 17B–C, E, 21C for the same features on USNM 1411124 and MNHN-IE-2014-2001). Table 2 indicates pattern of proximal articulations; all ligamentary articulations appear to be trifascial synarthries (see USNM 1411124 below for descriptions); one or two brachials of a triplet often shorter than others; pattern from IBr6 or 8 to IBr20–25 chiefly brachial pairs alternating with single free brachial; few successive pairs or two successive free brachials also present. Brachial pairs commonly separated by two free brachials beyond ~IBr30 with some series of 3–4 successive free brachials distally (beyond IBr50) (on detached arms). Plane of trifascial articulations distal to IBr6 tilted with respect to arm axis in lateral view, so that aboral face of distal ossicle of a pair is shorter (arrows in Figure 5). On remaining attached rays (2 now broken near bases), first pinnule on left side of IBr5+6 (2 cases), IBr6+7 (9 cases), IBr5+6+7 (3 cases) and on right side of IBr7+8 (1 case) (in aboral view with arm base down as in Figures 2, 9 B) (Table 2). Proximal two pinnulars of all pinnules short, ~ 0.3 mm high. First 4–5 pinnules on each side genital, 4.5 mm long, of 11 segments. Well-developed gonadal inflation extending from pinnular 4 to 8–10 (Figure 6 A); distalmost gonad smaller than others, extending along 3–4 pinnulars. First pinnular of genital pinnule with HW 1.3, second 1.0; following pinnulars becoming slender with expanded ends and HW>4.0; distal few pinnulars shorter. Pinnulars of gonadal inflation with thin lateral expansion. Gonads covered with thin, irregular, interlocking plates (Figure 6 A). Middle pinnules to 7 mm long with up to 19 pinnulars and HW to 8.0. Distal pinnules threadlike, to 10 mm long, of up to 22 pinnulars with HW of individual pinnulars up to 10.0. First pinnular of middle and distal pinnules with HW ~1.0, and with thin, distally-pointed, blade-like flange on lateral margin facing base of arm (see under Figure 17 F USNM 1411124 below). Ambulacral tissue of middle and distal pinnules containing numerous small fine single and irregularly branched needles, and few small coarse meshes (Figure 6 B, C). Disk (partly visible between two broken arms) flat, reaching level of IBr8, connected to arms by short narrow bridges that reach IBr9; interambulacral areas at least partly covered with extremely thin, polygonal interlocking plates. Description of USNM 1411124 (Figures 3 B–C, 4C, 7–18, Tables 1–2) (partly dissociated for SEM). Remaining stalk L= 398 mm, of 101 externally visible columnals (the distalmost broken); detached close to attachment disk (Figure 7). Proxistele of 7 visible columnals (C1–7) similar to holotype; weak synarthrial articulation visible externally between C7 and C8; C7 with D/d 1.03; end of fulcral ridge evident externally by C9– 10; pairs of columnals developing barrel-shaped profile by C15–16. No dististele retained; D and HD decreasing gradually from C84 to remaining distal end (Figure 3 C, D); D/d ~1.4 from mid-stalk to remaining end. Two pairs of columnals (C30+31, C87+88) tightly anchylosed; articulation appearing exteriorly as synostosis with no trace of syzygial pattern (see description of facets of similar-appearing articulations for USNM -IE-2014-2001 below).Published as part of Messing, Charles G., 2016, Porphyrocrinus daniellalevyae n. sp. (Echinodermata: Crinoidea), a sea lily from the tropical western Atlantic with a unique crown pattern, pp. 1-35 in Zootaxa 4147 (1) on pages 3-8, DOI: 10.11646/zootaxa.4147.1.1, http://zenodo.org/record/26283
FIGURE 7. Stephanometra tenuipinna. a–f. Proximal brachitaxes. a. USNM 1094091. b. NSUOC 312. c. USNM 35256. d. NSUOC 256. e in A revision of the comatulid genus Stephanometra AH Clark with a rediagnosis of the genus Lamprometra AH Clark (Echinodermata: Crinoidea)
No full textFIGURE 7. Stephanometra tenuipinna. a–f. Proximal brachitaxes. a. USNM 1094091. b. NSUOC 312. c. USNM 35256. d. NSUOC 256. e. IRSNB/CRI 389. f. IRSNB/CRI 387. g–i. Centrodorsal, aboral view. g. NSUOC 256. h. NSUOC 310. i. NSUOC 312. j–l. Centrodorsal, lateral view. j. FLMNH 6817. k. NSUOC 256. l. NSUOC 312. Scale bars: left (g, h, k) 3 mm, right (a–f, i, j, l) 2 mm.Published as part of Rankin, Dana L. & Messing, Charles G., 2008, A revision of the comatulid genus Stephanometra AH Clark with a rediagnosis of the genus Lamprometra AH Clark (Echinodermata: Crinoidea), pp. 1-35 in Zootaxa 1888 on page 12, DOI: 10.5281/zenodo.18429
Women s conditions in working life
No full textThis volume of Arbete och Hälsa (Work and Health) is a result of a workshop held in Brussels in September 2000. The workshop was one out of about 70 workshops that preceded the European Union Presidency Conference Work Life 2000 , that took place in Malmö in southern Sweden 22-25 January 2001. The about 70 workshops covered virtually every aspect of modern working life within the following categories: labour market, working environment, work organisation, information society, diversity in working life, small and medium-sized enterprises, as well as gender. The present workshop Women s Conditions in Working Life covered women s situation in terms of labour market conditions, work organisation, working environment, as well as health effects. The aim to present the state of the art about science and practice within these areas, as well as to point out possible areas for interventions, was explicit in the invitation to participate in the workshop. Content: Introduction Carina Bildt and Lena Karlqvist The new economy and the work life balance: opportunities and constraints for women and men Dianne Perrons Women and labour market regulation Pamela Meadows Gendered health consequences of unemployment among young people Anne Hammarström Gender and working conditions in the European Union Kaisa Kauppinen The importance of gender sensitive studies of work-related neck and upper limb disorders Lena Karlqvist Working conditions and mental health among women Carina Bildt Gender approaches in the EU Network Workplace Health Promotion Elisabeth Lagerlöf and Ewa Menckel Listening to women: Action-oriented research in ergonomics Karen Messing and Ana Maria SeifertSyftet med rapporten är att ge en vid bild av kvinnors villkor i dagens arbetsliv. Därför är uppsatser med såväl makro- som mikroperspektiv inkluderade, likväl uppsatser som fokuserar på forskning och utvecklings- och förändringsarbete. I samtliga uppsatser pekas områden ut där forskning och åtgärder behöver göras. Vi hoppas att forskare och beslutsfattare skall kunna använda sig av dessa förslag för att förbättra kvinnors villkor i arbetslivet. Den huvudsakliga strukturen på uppsatserna är att de är översiktsartiklar, med empiriska illustrationer av de fenomen som diskuteras. Två av uppsatserna fokuserar på metoder för att arbeta med förändringsarbete. Dianne Perrons ger i sin uppsats en bred bild av den nya ekonomin och dess konsekvenser för olika grupper i befolkningen. Hon diskuterar huruvida den medför möjligheter eller begränsningar för kvinnor och hur den påverkar organisationen av arbetet. Det empiriska exemplet är taget från en studie som genomförts inom mediasektorn i Brighton och Hull i England. Pamela Meadows konstaterar att diskussionen om syftet och effekten av arbetsmarknadsregleringar tenderar till att vara könsblind, dvs sakna perspektivet att regleringarna kan ha olika effekter för kvinnor respektive män. Sådan skillnader i effekter måste diskuteras när gamla regleringar utvärderas och när nya skall implementeras. Hälsoeffekter av arbetslöshet bland ungdomar är vad Ann Hammarström tar upp i sin uppsats. De allra flesta studier inom området har saknat ett könsperspektiv och varit fokuserade på individen, trots att effekten på såväl samhället som familjen är påtaglig. Hennes empiriska exempel utgörs av en longitudinell studie av mer än 1 000 svenska ungdomar som följts från det att de var 16 år. Kaisa Kauppinen ger dels en bild av hur arbetsmiljöförhållandena är för kvinnor inom EU och ger dels ett exempel på hur man kan arbeta med arbetsorganisatoriska förändringsprojekt för att uppnå en större jämställdhet inom olika företag. Lena Karlqvist diskuterar vikten av att beakta betydelsen av kön vid genomförandet av studier av arbetsrelaterade nack- och skulderproblem. Könssegregeringen på arbetsmarknaden leder till att kvinnor och män arbetar under olika betingelser, vilket får effekter på deras hälsa. Hon ger ett antal exempel på detta från olika empiriska studier. Kvinnors arbetsförhållanden i relation till psykisk hälsa är i fokus i Carina Bildts uppsats. Trots att yrkesarbete rent generellt är befrämjande för kvinnors hälsa finns det faktorer i arbetet som bidrar till försämrad psykisk hälsa. Till exempel har samband med hög upplevd belastning, skiftarbete, hög tidspress och tillfällig anställning kunnat identifieras som riskfaktorer för psykisk ohälsa. Förändringarna på arbetsmarknaden ger upphov till oro för en fortsatt försämring. Elisabet Lagerlöf och Ewa Menckel redovisar i sin uppsats en studie av hur kön implementerats i EU-nätverket Workplace Health Promotion . Syftet var att utreda huruvida strategin EU:s mainstreaming -policy hade varit framgångsrik. Det empiriska materialet utgörs av 66 fallstudier i 15 olika länder. I den avslutande uppsatsen ger Karen Messing och Ana Maria Seifert exempel på hur kvinnors ergonomiska villkor i arbetet kan förbättras genom ett samarbete mellan arbetstagare, lokala fackföreningar och forskare. Resultat från studier av flera olika yrkesgrupper redovisas för att illustrera den mera metodologiska inledande delen av uppsatsen
Frances Burney and her readers : the negotiated image
No full textIn Frances Burney and Her Readers, Anna Paluchowska-Messing traces the rugged trajectory marked by the literary career of Frances Burney, the English eighteenth-century novelist, diarist and playwright. The study highlights the techniques Burney employed in her texts for projecting a favourable self-image, and sets them against the changing conventions in culture consumption and appreciation. More broadly, the study addresses the concept of women’s literary celebrity, which in late eighteenth-century England remained at odds with contemporary ideals of feminine respectability and prescribed domesticicity. In Paluchowska-Messing’s representation, Burney’s story showcases the dilemmas an eighteenth-century author must face at different stages of her career from debutante to that of an acclaimed literary figure, and possible solutions she might choose in order to court celebrity without losing respectability
FIGURE 16. Lamprometra palmata. a–c. Cirri. a in A revision of the comatulid genus Stephanometra AH Clark with a rediagnosis of the genus Lamprometra AH Clark (Echinodermata: Crinoidea)
No full textFIGURE 16. Lamprometra palmata. a–c. Cirri. a. IRSNB/CRI 410. b. FLMNH 6828. c. NSUOC 345. d–g. Proximal brachitaxes. d. IRSNB/CRI 415. e. NSUOC 353. f. NSUOC 358. g. FLMNH 6833. h–i. Centrodorsal, aboral view. h. CRRF 1151L. i. NSUOC 357. j. Centrodorsal, lateral view, FLMNH 6844. Scales: upper (a–c), lower (d–j), all 2 mm.Published as part of Rankin, Dana L. & Messing, Charles G., 2008, A revision of the comatulid genus Stephanometra AH Clark with a rediagnosis of the genus Lamprometra AH Clark (Echinodermata: Crinoidea), pp. 1-35 in Zootaxa 1888 on page 27, DOI: 10.5281/zenodo.18429
Treatise on Invertebrate Paleontology
No full textThis volume is edited by Paul Selden, authors are Hans Hess and Charles G. Messing, coordinating author is William I. Ausich. This is the first volume to be published in an extensive revision of the Class Crinoidea. The present volume deals with the Subclass Articulata that contains all post-Paleozoic and living crinoids. The descriptions are preceded by an introduction, a chapter on the morphology of articulate crinoids, a glossary of important terms, and an overview of classification. The reference list is comprehensive for this volume.https://nsuworks.nova.edu/occ_facbooks/1009/thumbnail.jp
Rigid gauges and F-zips, and the fundamental sheaf of gauges Gn
No full textWe establish an equivalence of categories between a category of gauges and Moonens and Wedhorns category of F-zips. We prove that cohomology of Fontaines and Jannsens sheaf Gn is equal for different good topologies
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