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Pudoproetus Hessler 1963
No full textGenus Pudoproetus Hessler 1963 Type species. Proetus fernglenensis Weller 1909. Diagnosis. See Feist & Petersen (1995: 105). Remarks. Pudoproetus was first erected as a subgenus of Proetus by Hessler (1963). The subgenus classification was based on North American taxa of Mississippian age that shared characteristics with Devonian proetids (Feist & Petersen 1995; Hessler 1963). Hahn & Brauckmann (1988) elevated it as a monotypic genus within the Bollandiinae Hahn & Brauckmann 1988 due to it being much younger in age than other proetine taxa. This classification was questioned by Feist & Petersen (1995) based on it having a typical proetine glabellar outline, an absence of a frontal lobe and the presence of 10 thoracic segments. They also noted that the absence of taxa between the last proetine and Pudoproetus is not cause to remove it from the Proetinae subfamily entirely (Feist & Petersen 1995). The original designation of Pudoproetus in the family Proetidae is upheld herein. The subgenus P. (Megaproetus) was described by Jell (1977). Owens (1994) stated that differences between P. (Megaproetus) and Pudoproetus as noted by Jell could be variable between species and, therefore, considered P. (Megaproetus) a junior synonym of Pudoproetus a view followed here. Species included. Pudoproetus abnormis Yuan & Xiang 1998, Pudoproetus albiorix (Hahn et al. 1980), Pudoproetus auriculatus (Hall 1862), Pudoproetus brevis Yuan & Xiang 1998, Pudoproetus cambrertus (Jell 1977), Pudoproetus cellesensis (Hahn et al. 1980), Pudoproetus chappelensis (Hessler 1963), Pudoproetus expansus Yuan & Xiang 1998, Pudoproetus fernglenensis (Weller 1909), Pudoproetus guangxiensis guangxiensis (Zhu & Yuan 1988), Pudoproetus guangxiensis bellus Yuan & Xiang 1998, Pudoproetus hahni (Chamberlain 1977), Pudoproetus hoppeckensis Hahn et al. 2004, Pudoproetus incertus (Hahn et al. 1980), Pudoproetus mediterraneus Feist & Petersen 1995, Pudoproetus michiganensis (Hessler 1963), Pudoproetus missouriensis (Shumard 1855), Pudoproetus obsoletus (Kobayashi & Hamada 1978), Pudoproetus pila (Weber 1937), Pudoproetus priscus Feist & Petersen 1995, Pudoproetus sargaensis (Weber 1937), Pudoproetus teutates (Hahn et al. 1980), Pudoproetus toutiorix (Hahn et al. 1980), Pudoproetus ussuilensis (Weber 1937), Pudoproetus woodwardi (Etheridge Jr. 1892 a), Pudoproetus xiakouensis Yuan & Xiang 1998. Age and distribution. Late Devonian to Late Tournaisian, in Australia, China, Europe, North America and Russia (Hessler 1963; Feist & Petersen 1995; Owens 1994).Published as part of Vanderlaan, Tegan A. & Ebach, Malte C., 2015, A review of the Carboniferous and Permian trilobites of Australia, pp. 1-56 in Zootaxa 3926 (1) on pages 17-18, DOI: 10.11646/zootaxa.3926.1.1, http://zenodo.org/record/28800
M.-C. Hessler, Les maladies professionnelles dans la C.E.E. et en Suisse
No full textM.-C. Hessler, Les maladies professionnelles dans la C.E.E. et en Suisse. In: Revue internationale de droit comparé. Vol. 24 N°4, Octobre-décembre 1972. pp. 932-933
M.-C. Hessler, Les maladies professionnelles dans la C.E.E. et en Suisse
No full textM.-C. Hessler, Les maladies professionnelles dans la C.E.E. et en Suisse. In: Revue internationale de droit comparé. Vol. 24 N°4, Octobre-décembre 1972. pp. 932-933
Chorocaris Martin and Hessler 1990
No full textGenus Chorocaris Martin and Hessler, 1990 Rimicaris: Williams and Rona 1986: 447 (in part). Chorocaris Martin and Hessler, 1990: 2; Komai and Segonzac 2008: 32. Opaepele: Komai et al. 2007: 239 (in part). Type species Chorocaris vandoverae Martin and Hessler, 1990. Composition In addition to the type species, the following five species are here assigned to Chorocaris: Chorocaris chacei (Williams and Rona 1986), C. parva sp. nov., Chorocaris paulexa (Martin and Shank 2005), Chorocaris susannae (Komai et al. 2007) comb. nov. and C. variabilis sp. nov. Emended diagnosis Rostrum reaching or falling short of midlength of first segment of antennular peduncle, dorsoventrally flattened, triangular to rounded in dorsal view; dorsal surface usually non-carinate, always unarmed; ventral surface nearly flat or slightly convex, unarmed. Carapace without postrostral carina; shallow longitudinal depression on either side of midline in spawning females; antennal tooth distinct, varying from acute to blunt; pterygostomial angle produced anteriorly or non-produced; anterior part of branchial region not strongly inflated; pair of dorsal organs evident in postorbital region in living specimens. Pleon with third pleuron unarmed; fourth pleuron unarmed or with one or more denticles posteroventrally; fifth pleuron with posteroventral tooth and occasionally with additional teeth or denticles on posterolateral margin. Telson with dorsolateral spines arranged in sinuous row with second and/or third spines located distinctly mesial to other spines; posterior margin convex, with row of plumose setae flanked by two pairs of lateral spines. Eyes broadly fused, with faint median notch; anterior surface of each eye flat anteriorly, unarmed. Antennular stylocerite clearly separated from first peduncular segment. Antennae usually not forming operculate structure (see Martin and Hessler 1990); antennal scale with sharp to blunt distolateral tooth, clearly separated from lamella or closely approximated to it; transverse suture present, extending mesially from base of distolateral tooth. First maxilliped with rudimentary bud of flagellum on exopod. First pereopod with welldeveloped grooming apparatus on carpus. Second pereopod without spine on ischium. Third to fifth pereopods increasing in length posteriorly; dactyli each with two or more rows of accessory spinules on flexor surfaces; meri of third and fourth pereopods unarmed; ischia of third and fourth pereopods unarmed (except for males of C. variabilis sp. nov.). No strap-like epipods on third maxilliped or first to fourth pereopods. Appendix interna on fourth pleopod without terminal cluster of coupling hooks. Uropodal exopod with two posterolateral spines mesial to posterolateral tooth; protopod sharply to bluntly pointed posterolaterally. Distribution Hydrothermal vents in the western and eastern Pacific and on the Mid-Atlantic Ridge; 1305–3650 m. Remarks The genus Chorocaris was established by Martin and Hessler (1990) to accommodate the type species C. vandoverae from hydrothermal vents in the Mariana Back Arc Basin, and Rimicaris chacei Williams and Rona, 1986 from hydrothermal vents along the Mid-Atlantic Ridge. Chorocaris was differentiated from Rimicaris by the more-developed rostrum, the non-inflated branchial regions of the carapace, the cylindrical fused eyestalks and the non-operculate antennae (Martin and Hessler 1990). A new species Chorocaris fortunata Martin and Christiansen, 1995 was subsequently described from the Lucky Strike vent field on the Mid-Atlantic Ridge, but this species was later transferred to Mirocaris by Vereshchaka (1997). Based on analyses of the COI gene (600 bp), Shank et al. (1999) proposed that Chorocaris is a paraphyletic assemblage with C. chacei being more closely related to Rimicaris exoculata than to C. vandoverae. Martin and Shank (2005) described a new species, C. paulexa, from the Rapa Nui Homer Vent Site on the southern East Pacific Rise. Komai et al. (2007) then described a new species, Opaepele susannae Komai et al. 2007, from the southern Mid-Atlantic Ridge, and suggested that their new species appears to be intermediate between Chorocaris and Opaepele. Komai and Segonzac (2008) reviewed Chorocaris and Rimicaris, and took a conservative approach by recognizing three species in Chorocaris, namely, C. chacei, C. paulexa and C. vandoverae; these authors maintained the genus despite the possibility of it being paraphyletic. Recently, a new species, Rimicaris hybisae Nye, Copley and Plouviez, 2012, was described from the Mid-Cayman Spreading Centre, in the Caribbean; this species was provisionally referred to Rimicaris, but exhibits some similarities to C. chacei (see Nye et al. 2012). The discovery of the two new species, herein referred to Chorocaris, led us to reassess the characters that differentiate the genera Chorocaris and Opaepele. Comparison of C. vandoverae and Opaepele loihi, the type species of the respective genera, has confirmed the following morphological differences: (1) the rostrum is devoid of a dorsal carina or dorsal teeth or denticles in C. vandoverae, whereas in O. loihi, the rostrum has a distinct dorsal carina, extending to the postrostral part of the carapace, and occasionally bears minute denticles; (2) the uropodal exopod always bears two movable spines at the posterolateral angle in C. vandoverae, whereas there is usually one, rarely two, movable spines just mesial to the fixed posterolateral tooth in O. loihi. The two previously known species of Chorocaris (C. chacei and C. paulexa), O. susannae and the two new species of Chorocaris described herein are morphologically akin to C. vandoverae in these regards. The lack of a dorsal carina on the rostrum and the possession of two posterolateral spines on the uropodal endopod are presumed to be apomorphic within the Alvinocarididae (cf. Komai and Segonzac 2003, 2004, 2008). Consequently, Opaepele loihi is set apart from a group, which includes Opaepele susannae, Chorocaris species including the two new species described herein, and Rimicaris species. Despite the suggested paraphyly of Chorocaris, we recognize Chorocaris as a valid genus for the time being, including C. vandoverae, C. chacei, C. paulexa, C. parva sp. nov., C. variabilis sp. nov. and C. susannae comb. nov. until thorough phylogenetic analysis is performed. In addition, Opaepele vavilovi has a number of presumably plesiomorphic characters, such as the dorsolateral spines on the telson being arranged in a linear row, the presence of a spiniform tubercle on the rounded anterior surface of each eye, the possession of meral and/or ischial spines on the second to fourth pereopods and the presence of a single row of accessory spinules on the dactyli of the third to fifth pereopods. In these regards, O. vavilovi is similar to species of Alvinocaris, and could be excluded from a group of genera containing Alvinocaridinides, Chorocaris, Opaepele, Rimicaris and Shinkaicaris. Future study has the potential to warrant the establishment of a separate genus for O. vavilovi.Published as part of Komai, Tomoyuki & Tsuchida, Shinji, 2015, New records of Alvinocarididae (Crustacea: Decapoda: Caridea) from the southwestern Pacific hydrothermal vents, with descriptions of one new genus and three new species, pp. 1789-1824 in Journal of Natural History 49 (29) on pages 1791-1793, DOI: 10.1080/00222933.2015.1006702, http://zenodo.org/record/400022
On the classification of perfect codes: Extended side class structures
No full textAbstractThe two 1-error correcting perfect binary codes, C and C′ are said to be equivalent if there exists a permutation π of the set of the n coordinate positions and a word d̄ such that C′=π(d̄+C). Hessler defined C and C′ to be linearly equivalent if there exists a non-singular linear map φ such that C′=φ(C). Two perfect codes C and C′ of length n will be defined to be extended equivalent if there exists a non-singular linear map φ and a word d̄ such that C′=φ(d̄+C).Heden and Hessler, associated with each linear equivalence class an invariant LC and this invariant was shown to be a subspace of the kernel of some perfect code. It is shown here that, in the case of extended equivalence, the corresponding invariant will be the extension of the code LC.This fact will be used to give, in some particular cases, a complete enumeration of all extended equivalence classes of perfect codes
On the classification of perfect codes : side class structures
No full textThe side class structure of a perfect 1-error correcting binary code (hereafter referred to as a perfect code) C describes the linear relations between the coset representatives of the kernel of C. Two perfect codes C and C' are linearly equivalent if there exists a non-singular matrix A such that AC = C' where C and C' are matrices with the code words of C and C' as columns. Hessler proved that the perfect codes C and C' are linearly equivalent if and only if they have isomorphic side class structures. The aim of this paper is to describe all side class structures. It is shown that the transpose of any side class structure is the dual of a subspace of the kernel of some perfect code and vice versa; any dual of a subspace of a kernel of some perfect code is the transpose of the side class structure of some perfect code. The conclusion is that for classification purposes of perfect codes it is sufficient to find the family of all kernels of perfect codes.</p
Ipoa TENDAL & HESSLER 1977
No full textGENUS <i>IPOA</i> TENDAL & HESSLER, 1977 <p> <i>Type species</i>: <i>Ipoa fragila</i> Tendal & Hessler, 1977</p> <p> <i>IPOA FRAGILA</i> TENDAL & HESSLER, 1977</p> <p>(FIGS 10, 11)</p> <p> <i>Ipoa fragila</i> Tendal & Hessler, 1977, p. 181, pl. 9 fig. D, pl. 11, fig. C–D</p> <p> <i>Ipoa fragilis</i> Tendal & Hessler. Schröder, Medioli & Scott, 1989, p. 24, 28; pl. 1, fig. 1–3; pl. 8, fig. 4; textfig. 7</p> <p> <i>Ipoa fragila</i> Tendal & Hessler. Kamenskaya, 1993, p. 79</p> <p> <i>Diagnosis</i>: Test periphery contained within a rounded, often oval, slightly flattened envelope. Central tubule often discernible; irregular in width, and typically constricted where it gives rise to a relatively small number of primary branches. These main trunks radiate from central part and break up into burst of tightly spaced peripheral branches, giving them tree-like appearance. Diameter of tubules decreases markedly with each branching. Tubules non-septate. (Modified after Tendal & Hessler, 1977.)</p> <p> <i>Holotype</i>: <i>Argo</i> H-30, central North Pacific, epibenthic sledge sample: 30°05′N, 156°12′W; 6065–6079 m water depth. Zoological Museum, Copenhagen; preserved in alcohol.</p> <p> <i>ANDEEP material</i>: Stn 59#9, 1 small fragment; Stn 59#11, 2 fragments; Stn 88#5, 1 specimen; Stn 88#7, 1 specimen; Stn 88#8, 4 complete, 10 fragments; Stn 94#5, 1 specimen; Stn 94#11 4 larger?complete, 18 fragments; Stn 94#14, 4 complete specimens, 2 fragments; Stn 102#10, 1 small piece; Stn 102#13, 1 specimen; Stn 110#8, 12 complete, 3 fragments.</p> <p> <i>Description of holotype</i></p> <p>The holotype is light brownish in colour and consists of one large and numerous tiny fragments (Fig. 10). It is much less complete than shown in the photograph of Tendal & Hessler (1977: pl. 9, fig. D). The large piece measures 1.67 × 1.33 mm and consists mainly of the inner branches that are 120–140 µm in diameter. These main branches give rise to narrow tubules, end- ing in twig-like branches 40–50 µm in diameter. Many of the branches are broken.</p> <p> <i>Description of ANDEEP material</i></p> <p>A number of specimens from Stns 88, 94 and 110 appear to be complete. They have a generally rounded, sometimes oval and usually more or less flattened shape (Fig. 11A–F). The largest is 3.1 mm long, 2.5 mm wide and 2.0 mm high. Other specimens that we judge to be more or less complete measure 1.7– 2.5 mm long, 1.0– 2.5 mm wide and 0.8–1.6 mm high. The central tubule is irregular in width (100–140 µm), and often constricted one or more times where it gives rise to the relatively small number of primary branches, typically ∼80 µm in diameter. It is not always possible to distinguish clearly between the cen- tral and the primary tubules. In one complete specimen, the central tubule has a closed end, presumably the initial part. The broader inner tubules branch repeatedly into a profusion of narrow outer branches, 30–60 µm in diameter. The walls of the tubules are composed of fine-grained particles studded with small, often angular quartz grains (20–40 µm in diameter). Some specimens incorporate a few large mineral grains or planktonic foraminiferal tests.</p> <p> <i>Remarks</i></p> <p>The ANDEEP material includes a larger number of complete individuals than were available to Tendal & Hessler (1977). In the largest holotype fragment, the inner primary branches are prominent and rather wider than in typical ANDEEP specimens. Tendal & Hessler give diameters of 150–190 µm for these primary branches compared with 100–140 µm in our specimens. In other respects, however, our specimens conform closely to Tendal & Hessler’s (1977) description.</p> <p> <i>Distribution</i></p> <p> First described from the Central North Pacific (Tendal & Hessler, 1977), subsequently from ∼ 5770 m water depth on the Nares Abyssal Plain, north-west Atlantic (Schröder <i>et al</i>., 1989) and at two stations (2790 and 4912 m) in the Cape Basin (Kamenskaya, 1993). In our material it occurs in the eastern and central Weddell Sea (4649–4934 m).</p> <p> IPOA PENNATA <b>SP. NOV.</b></p> <p>(FIGS 12, 13)</p> <p> <i>Diagnosis</i>: Test bush-like; inner part consists of wide primary tubules that divide into narrower peripheral branches. These outer branches follow a more or less crooked course and give rise to short side branches, usually either more or less tubular or, less commonly, bead-like in shape. Tubules non-septate.</p> <p> <i>Type material and locality</i>: The holotype and two paratypes were collected from Stn 88#7 using a large boxcorer (Grosskastengreifer); 68°3.61′S, 20°27.99′W; 4934 m water depth. They are preserved in 4% buffered formalin and deposited in the ForschungsInstitut Senckenberg, Frankfurt am Main, under reg. nos. SMF XXVII 7531 (holotype) and XVII 7532 (two paratypes).</p> <p> <i>Other material examined</i>: Stn 88#8, 24 specimens; Stn 94#7, 1 specimen; Stn 102#8, 2 specimens; Stn 102#13, 26 larger specimens and 15 obvious fragments.</p> <p> <i>Derivation of name</i>: Latin <i>pennatus</i> = with feathers, alluding to the sometimes feathery appearance of the test branches.</p> <p> <i>Description of type specimens.</i></p> <p> <i>Holotype</i>: The test measures 1.80 × 1.30 mm and is rather flattened (Fig. 12B). It forms a bush-like structure with branches radiating out from a central region. Individual tubules can be seen clearly only around the periphery of the test. The inner part consists of a compact cluster of branches that obscures the central structure. The individual branches become clearer in the outer half of the test. They have an irregular and complex form in which a more or less tubular shaft, 60–80 µm in diameter, gives rise to short, unevenly spaced side branches. Many of these are also tubular in form but the shorter ones are more beadlike. On one branch, short, paired, forward-pointing side tubules create two arrowhead-like sections joined by a narrow neck (Fig. 12D).</p> <p> <i>Paratype 1</i>: The test measures approximately 2.0 × 1.7 mm and is somewhat flattened and rather less compact than the holotype (Fig. 12A, B). The structure of the branches is similar to that seen in the holotype. Neck-like constrictions between some sections of the branches create chain-like formations.</p> <p> <i>Paratype 2</i>: The second paratype measures 1.95 × 1.45 mm and is distinctly flattened (Fig. 12E). The structure is more open than that of other two type specimens. The inner part of the test has several short, thick branches, 100–160 µm in diameter, which merges into the narrower, peripheral branches. These outer branches are crooked with short, mainly tubular side branches (Fig. 12F).</p> <p>In all three type specimens, the wall is off-white in colour. It is opaque, soft, fine grained but with scattered small quartz grains (usually no more than 20 µm in size) which glint in reflected light, and small dark grains. Large agglutinated particles are not present. The test interior is occupied by large, oval stercomata, most of them 25–40 µm in maximum dimension. There are no septa.</p> <p> <i>Description of other material.</i></p> <p> <i>Stn 88#8</i>: Specimens range in size from 1.20 × 1.00 mm to 1.30 × 1.80 mm. In many cases, the thicker central branches are clearly developed. These sometimes consist of several lobate sections separated by constrictions (Fig. 13B). The branching pattern of the narrower peripheral branches is often difficult to discern but seems to be largely dichotomous. The available material exhibits some variation, particularly in the development and form of the side branches of the main peripheral branches (Fig. 13C, D). The side branches are often more or less tubular (cylindrical) but some of the shorter ones taper and are more conical in shape. In places, the branches are interrupted by necks to create one or more irregularly shaped segments. One specimen has a compact test and distinctly thicker side branches which give it a less delicate appearance than typical specimens.</p> <p> <i>Stn 102</i>: Specimens measure from 1.20 × 1.30 mm to 1.80 × 2.00 mm. The thicker central branches are often clearly developed and rather irregular in width (80–140 µm) (Fig. 13A, E, F). The side branches are usually 40–60 µm in diameter and similar in shape to those of the type specimens. However, in one case, they form rather elongate, finger-like projections while in another they are rounded and bead-like in form. The test wall is ∼15–30 µm thick and similar in colour to specimens from Stn 88. The wall incorporates a few fairly large particles (100–200 µm), in addition to numerous tiny quartz grains.</p> <p> <i>Remarks</i></p> <p> We place this species in the genus <i>Ipoa</i> based on the presence of thick, radiating, basal branches which occupy the inner part of the test and divide to form narrower, peripheral branches. A distinctive feature of the new species, which distinguishes it from <i>Ipoa fragila</i>, is that the peripheral branches give rise to short, irregularly developed lateral processes, tubular, conical, or less commonly bead-like in form. The branches are also sometimes interrupted by narrow constrictions that divide them into one or more short, distinct sections. Interestingly, these sections resemble parts of some chain-like komokiaceans, notably <i>Arbor multiplex</i>, as illustrated by Schröder <i>et al</i>. (1989), as well as the chambers of <i>Edgertonia floccula</i>, as illustrated by Shires, Gooday & Jones (1994). However, the fine ‘fibres’ present in these species have not been observed in specimens of <i>Ipoa pennata.</i></p> <p> <i>Distribution</i></p> <p>The new species occurs in the central Weddell Sea (4803–4934 m water depth).</p>Published as part of <i>Gooday, Andrew J., Kamenskaya, Olga E. & Cedhagen, Tomas, 2007, New and little-known Komokiacea (Foraminifera) from the bathyal and abyssal Weddell Sea and adjacent areas, pp. 219-251 in Zoological Journal of the Linnean Society 151 (2)</i> on pages 234-240, DOI: 10.1111/j.1096-3642.2007.00326.x, <a href="http://zenodo.org/record/5428216">http://zenodo.org/record/5428216</a>
Studium und Beruf - Praxiskonzepte von Studierenden der Soziologie und Sozialwissenschaften
No full textHessler G, Oechsle M. Studium und Beruf - Praxiskonzepte von Studierenden der Soziologie und Sozialwissenschaften. In: Schubarth W, Speck K, Seidel A, Gottmann C, Kamm C, Krohn M, eds. Studium nach Bologna: Praxisbezüge stärken?!. Wiesbaden: Springer VS; 2012: 113-126
Going Beyond Counting First Authors in Author Co-citation Analysis
No full textThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
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