213 research outputs found
Haliclona (Flagellia) hentscheli Van Soest 2017
No full textHaliclona (Flagellia) hentscheli subgen. et nom. nov. Fig. 9 Gellius incrustans Hentschel 1912: 390, pl. XV fig. 3, pl. XXI fig. 45. Etymology The specific epithet refers to E. Hentschel, author of Gellius incrustans. Material examined INDONESIA: South Sulawesi, Tana Djampea, Kambarangi Bay, 7.1058° S, 120.6274° E, depth 0–32 m, trawl, coll. Siboga Expedition stat. 64, 4 May 1899 (ZMA Por. 01225), same data as for previous (ZMA Por. 01226); Maluku,Ambon,Ambon Bay, near Hative Besar, 3.6833° N, 128.1333° E, 0–5 m, snorkeling, coll. R.W.M. Van Soest, Snellius II Expedition stat. 002/II/18A, 6 Sep. 1984 (ZMA Por. 08797); Snellius II Expedition, fieldnr 4.045, NE coast of Sumba, E of Melolo, 9.9033° S, 120.7167° E, depth 48–57 m, Van Veen grab, 13 Sep. 1984 (unregistered slide); Snellius II Expedition, fieldnr 56J, NE coast of Sumba, E of Melolo, 9.9° S, 120.7477° E, depth 125 m, dredge, 14 Sep. 1984 (unregistered slide). Description Encrusting sponges with an uneven surface (Fig. 9A), with slightly raised oscules (Fig. 9A 1). One (ZMA 01225, Fig. 9A) encrusts the base of an octocoral. Greyish beige in alcohol. Lateral size up to 2 × 1 cm, thickness 3–4 mm, oscules 2 mm in diameter. Consistency soft. SKELETON. Confusedly Haliclona -like, with paucispicular primary tracts interconnected by single oxeas. Special surface reticulation lacking. No visible spongin. OXEAS (Fig. 9 B–B1). Sharply pointed, straight, in a narrow size range, 198– 214 –238 × 4– 6. 4 –11.5 μm. FLAGELLOSIGMAS (Fig. 9 C–E). Circular to ovoid in shape, in two size categories. Larger ones (Fig. 9 C– D) with rather short but distinctly upturned long endings (Fig. 9C 1), both large and small ones with gradually widely curved short endings (Fig. 9C 2, E). Large flagellosigmas (I), with length of long endings 69– 84 –98 μm, short endings 51– 54 –63 μm, widths 53– 66 –83 μm, thickness 1.5– 1. 7 –2 μm. Small flagellosigmas (II) (Fig. 9 E–F), with length of long endings 27– 42 –66 μm, short endings 16– 24 – 34 μm, widths 18– 29 –39 μm, thickness 0.5– 0. 8 –1.5 μm. NORMAL SIGMAS (Fig. 9 G–H). The most common microscleres, occurring in two distinct size classes, the larger ones (I) (Fig. 9G) with rather sharply bent endings, robust, 57– 71 –81 × 1.5– 2. 4 –3 μm, the smaller thinner ones (II) (Fig. 9H) incurved more roundedly, 14– 22 –32 × 0.5– 0. 6 –1 μm. Distribution and ecology Indonesia: Aru Islands, Tana Djampea (island south of Sulawesi), Ambon, Sumba (Marine Ecoregions Arafura Sea, Banda Sea, Lesser Sunda), coral reefs and sand bottoms at 12–125 m depth. Remarks The specimens described here are judged to be conspecific with Gellius incrustans Hentschel, 1912. However, data provided by Hentschel do not entirely match the present specimens: normal sigmas are described as very common, but no size categories were mentioned; only the largest size is quoted as 43– 56 μm, smaller than the present 57–81 μm. Flagellosigmas are quoted as having a largest ‘Durchmesser’ of 47–51 μm, likewise smaller than in the present specimens. Oxeas were 156–180 × 5–6 μm, according to Hentschel. It remains to be established whether the differences observed here are the result of a less than optimal description by Hentschel, or a genuine difference, in which case the present specimens belong to an undescribed species. Apart from these differences, transferring Gellius incrustans to the combination Haliclona (Flagellia) incrustans, created a junior secondary homonym of Haliclona foraminosa incrustans (Czerniavsky, 1880) (originally Protoschmidtia foraminosa forma incrustans) and of Haliclona simulans incrustans (Carter, 1887) (Carter 1887: 70, originally Isodictya simulans var. incrustans). Burton (1959b: 220) already solved the latter case of homonymy by giving Carter’s subspecies the new name Haliclona carteri Burton, 1959. Here the new combination Haliclona (Flagellia) hentscheli nom. nov. is proposed to solve the homonymy with Czerniavsky’s (1880) species, which, in spite of its unrecognizable description remains a senior secondary homonym until such time as its status is resolved. Future reallocation of these species to other valid genera will require reinstatement of Hentschel’s and Carter’s names. Burton’s (1928) deep-water record of Gellius flagellifer from the nearby Andaman Sea was possibly the present species, as the upper size of the normal sigmas falls within the variation of the above measurements. However, the oxeas of the Andaman specimens are 280–360 × 12–14 μm, well in excess of those measured above. Combined with the deepwater occurrence (300–900 m) the conspecificity appears doubtful.Published as part of Van Soest, Rob W. M., 2017, Flagellia, a new subgenus of Haliclona (Porifera, Haplosclerida), pp. 1-48 in European Journal of Taxonomy 351 on pages 17-19, DOI: 10.5852/ejt.2017.351, http://zenodo.org/record/383621
The coevolution of renewable resources and institutions - implications for policy design
No full text This PhD thesis studies how natural renewable resources and institutions governing those resources mutually influence each other. Theoretical models are developed in which members of a small community have joint access to a common pool resource. We analyze under which circumstances social norms of cooperation evolve that effectively regulate resource exploitation, but also when those social norms break down, identifying obstacles for community governance. Furthermore, in the light of biological and social complexity this thesis analyzes how governmental policy should be designed if self-governance is not sufficient to protect the resource stock. The insights obtained are applied to the case of Arcto-Norwegian cod. An optimal management plan is developed that can be adapted to several policy objectives concerning the utilization of the fleet. In addition, management advice is given for the case that harvesting may trigger an evolutionary response of the fish stock. </p
Detrital zircon and apatite (U‐Th)/He geochronology of intercalated baked sediments: a new approach to dating young basalt flows
No full textSimple numerical models suggest that many basaltic lava flows should sufficiently heat the sediments beneath them to reset (U‐Th)/He systematics in detrital zircon and apatite. This result suggests a useful way to date such flows when more conventional geochronological approaches are either impractical or yield specious results. We present here a test of this method on sediments interstratified with basalt flows of the Taos Plateau Volcanic Field of New Mexico. Nineteen zircons and apatites from two samples of baked sand collected from the uppermost 2 cm of a fluvial channel beneath a flow of the Upper Member of the Servilleta Basalt yielded an apparent age of 3.487 ± 0.047 Ma (2 SE confidence level), within the range of all published 40Ar/39Ar dates for other flows in the Upper Member (2.81–3.72 Ma) and statistically indistinguishable from the 40Ar/39Ar dates for basal flows of the Upper Member with which the studied flow is broadly correlative (3.61 ± 0.13 Ma). Given the high yield of 4He from U and Th decay, this technique may be especially useful for dating Pleistocene basalt flows. Detailed studies of the variation of (U‐Th)/He detrital mineral dates in sedimentary substrates, combined with thermal modeling, may be a valuable tool for physical volcanologists who wish to explore the temporal and spatial evolution of individual flows and lava fields.</p
De produktie van aceetaldehyde uitgaande van ethanol
No full textDocument(en) uit de collectie Chemische Procestechnologie.DelftChemTechApplied Science
Graphice, the use of the pen and pensil, or, The most excellent art of painting : in two parts /
No full textSignatures: [A]² a-c² B-Z².Three full-page engraved ports. by William Faithorne: William Sanderson after Souse (i.e. Soest?); Maria Ruten (i.e. Mary Ruthven), after a painting by her husband, Anthony van Dyke; Charles I after an unknown artist.Added t.p., c1r.Wing (2nd ed.)Mode of access: Internet.Theodore Besterman's calligraphic label, signed P.S. Ownership inscription of D. Giffan at head of t.p.Binding: modern sprinkled goatskin, tooled in blind. Author & title in gilt on spine label. Edges red
Convergence and international policy coordination in the EU: A dynamic games approach
No full textMaastricht Treaty;Dynamic Games;EU;Game Theory;International Policy
Local strong D-Monotonicity of the Kalai-Smorodinsky and Nash bargaining solution
No full textbargaining
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