197,090 research outputs found
Megalomma pacifici
No full textMegalomma pacifici (Grube, 1859) Figures 19A–K, 20A–J Sabella pacifici Grube, 1859: 9. Pseudopotamilla panamica Chamberlin, 1919: 268–269, Pl. 3, Fig. 8 fide Knight-Jones, 1997: 314. Megalomma pacifici.— Knight-Jones, 1997: 316, Figs 1A–E. Type material examined. [ZMUC] POL–1985, holotype incomplete (lacking posterior abdomen) of Sabella pacifici Grube, 1859, Punta Arenas, Costa Rica. [MCZ] 72, holotype complete (but broken in two parts) of Pseudopotamilla panamica Chamberlin, 1919, Panama, Coll. A. Agassiz with the following note in label: “In 1937 species identified by Hartman as M. vesiculosum (Montagu), reported in the Bull MCZ Vol. LXIII, No 6: 268–69”. Additional material examined. [Harlan Dean, personal collection ] Costa Rica, Bahía Salinas, Coll. Dean, H., on rocky intertidal (1 female). Playa Panamá, Papaguayo, Colls Dean, H. & J. A. Vargas, August 1999, rocky intertidal (1 spec.). [ZMUC] POL–1986, Costa Rica, Punta Arenas, Realejo, September 1845, Legit Orsted (1 female). [USNM] Acc. 292580, Panama, Shore of Perico Island, Sta. 252–1, lower part of sand beach, soft mud, hard sand/shell, January 25, 1978, Coll. Jones, M. L. (1 spec.). [ECOSUR] OH-P0282, Guerrero, Acapulco, Hornos beach, 16° 51’ 6.4’’ N, 99° 54’ 1’’ W, April 20, 2008, Colls SISV & LFCP, in sponge (1 spec). [ECOSUR] OH-P0284, Oaxaca, Pueto Angel, Panteon Beach, 15° 39’ 51.7’’ N 96° 29’ 44.8’’ W, April 16, 2008, Colls SISV & LFCP, in sabellariid reef (1spec). [ECOSUR] OH-P0285, Guerrero, Acapulco, Hornos beach, 16° 51’ 6.4’’ N, 99° 54’ 1’’ W, April 19, 2008, Colls SISV & LFCP, in oyster Spondylus calcifer (1 spec). [ECOSUR] OH-P0287, Oaxaca, Pueto Angel, Panteon Beach, 15° 39’ 51.7’’ N, 96° 29’ 44.8’’ W, April 16, 2008, Colls SISV & LFCP, in sabellariid reef (1 spec.). [ECOSUR] OH-P0289, Guerrero, Acapulco, Hornos beach, 16° 51’ 6.4’’ N, 99° 54’ 1’’ W, April 19, 2008, Colls SISV & LFCP, in oyster Spondylus calcifer (1 spec.). Diagnosis. Eyes in most radioles (spherical); ocular spots in ventralmost radioles; dorsal margins of collar fused to faecal groove; thoracic chaetae Type C; abdominal chaetae broadly hooded. Description. Branchial crown longer than thorax with 24 radiolar pairs (12–20). Branchial crown with orange bands along entire length (brown in old preserved material). Outer surfaces of radioles quadrangular basally, rounded distally. Sub-distal compound eyes present in most radioles. Dorsalmost pair of radioles with large, spherical and short tips (Figs 19D, 20J). Lateral and ventral radioles with spherical eyes decreasing their size towards ventral radioles (Fig. 19E–F). Ventralmost radioles with ocular spots and long tips (Fig. 19G). Dorsal collar margins rounded posteriorly, fused to faecal groove, forming broad gap (Figs 20B, H, 19A–B). Dorsal lappets absent. Dorsal pockets well developed (Figs 19A–B, 20B, H). Ventral lappets triangular, not overlapping (Figs 19C, 20C, F). Anterior peristomial ring exposed dorsally between dorsal pockets. Lateral margins of collar covering basal union of radioles (Figs 19B–C). Dorsal lips erect, triangular about one-quarter length of branchial crown, with midrib and dorsal pinnular appendages. Ventral lips short, broadly rounded. Ventral sacs present. Caruncle and keel absent. Total thorax-abdomen length 34 (19–34) mm, maximum width 5 (2) mm throughout most of thorax. Seven thoracic chaetigers (7). Dorsal thorax dark, except for faecal groove. Lateral margin of ventral thoracic shields brown colored. Ventral shields orange. Thoracic tori longest on chaetigers 2–3. Tori in chaetigers 2–3 occupy the entire distance between notopodia and ventral shield margins (Figs 19C, 20D–E), contacting shields. Inferior thoracic chaetae Type C (Fig. 19H). Thoracic uncini with crest surmounted by 8–10 rows of numerous minute teeth, handles 2x length of main fang (Fig. 19I). Companion chaetae with teardrop-shaped membranes (Fig. 19I). Abdomen with 40 chaetigers (42–65). Abdominal chaetae broadly hooded (Fig. 19K); chaetae in posterior row longer than those in anterior row. Abdominal uncini with main fang surmounted by 8–10 rows of numerous minute teeth (Fig. 19J). Pygidium trilobed with three groups of 4–5 red pygidial eyespots, unequal in size (Fig. 20I). Abdominal posterior of holotype regenerating (Fig. 20G). Tube attached to large basal stone and composed by shell fragments, echinoderm spines and coralline sand (Fig. 20A). Remarks. Megalomma pacifici, M. circumspectum and M. georgiense n. sp., share the presence of ocular spots in ventralmost radioles. In M. georgiense n. sp., the dorsal collar margins are not fused to faecal groove (fused in M. pacifici and M. circumspectum). Megalomma pacifici differs from M. circumspectum by having the anterior peristomial ring exposed between dorsal pockets (not exposed in M. circumspectum) and the thoracic tori longest in chaetigers 2–3 and in contact with ventral shields (same length in all segments and separate from ventral shields in M. circumspectum).Published as part of Tovar-Hernández, María Ana & Carrera-Parra, Luis F., 2011, Megalomma Johansson, 1925 (Polychaeta: Sabellidae) from America and other world-wide localities, and phylogenetic relationships within the genus 2861, pp. 1-71 in Zootaxa 2861 (1) on page 44, DOI: 10.11646/zootaxa.2861.1.1, http://zenodo.org/record/528635
Scheduling assembly tasks with caterpillar precedence constraints on dedicated machines
No full textIn this work, we address the problem of scheduling a set of n non-preemptive tasks on m dedicated machines in order to minimise the makespan. For each task deterministic processing times and a specific processing machine are given, moreover a set of precedence constraints among the tasks are known. We present a heuristic and some lower bounds on the minimum makespan for a relevant case in manufacturing applications, namely when the precedence constraints form a caterpillar graph. A caterpillar is a directed tree consisting of a single directed path and leaf nodes each of which is incident to the directed path by exactly one incoming arc. A number of computational experiments are also performed in order to test the performance of the proposed solution algorithm
Modeling an assembly line for configuration and flow management
No full textIn its basic form the management control of a flexible production system requires to assign a set of operations to a set of machines, and to connect machines by a transportation network, such that a number of constraints is satisfied and some efficiency index is optimized. The aim of the work is to give a general framework to formulate and model, in a formal way, different subproblems arising from embedding an assembly process on different configurations of a flexible production system. Because of the complexity of the overall problem, it is useful to have simple and well structured layouts and procedures that help the design and operation of flexible systems. These layouts and procedures induce additional constraints, due to the products' and the process' features. The paper also investigates the complexity of various subcases of the problem. (C) 1998 Elsevier Science Ltd, All rights reserve
Use of dermal-fat grafts in the post-oncological reconstructive surgery of atrophies in the zygomatic region: clinical evaluations in the patients undergone to previous radiation therapy
No full textAbstract
Introduction: Grafting of autologous adipose tissue can be recommended in some cases of facial plastic surgery.
Rhabdomyosarcoma is a type of cancer that can also affect the orbit. Enucleation of the eye can cause atrophy of
the corresponding hemiface and decreased orbital growth.
Case report: We report a case of a female patient with a medical history of surgical enucleation of the right
eyeball, who had received rhabdomyosarcoma radiation therapy in her youth. The patient presented with a
depression in the right zygomatic region. We took a dermal-fat flap from the abdominal region, which had been
previously treated.
Results: The surgical outcome, 48 hours, and much clearly 31 days after the surgery, revealed that the
right zygomatic region had returned to its proper anatomical shape, although there were still signs of
postoperative edema.
Discussion: Very damaged tissues, like those exposed to radiation therapy, are generally not suitable for grafting of
adipose tissue.
Conclusions: In the described case, we achieved a technically and aesthetically satisfying result despite the
patient's medical history involving several perplexities about the use of autologous dermal-fat tissues, because of
prior radiation therapy exposure. The clinical case shows that even a region exposed to radiation therapy can be a
valid receiving bed for dermal-fat grafting
Materiale edilizio (V)
No full textNell'ambito delle attività di ricerca in collaborazione tra l'Università di Roma "La Sapienza" e la Soprintendenza Archeologica dell'Etruria Meridionale gran spazio si è dato alle problematiche relative alla città di Veio, sia per quanto riguarda l'abitato che le necropoli. Il contributo prende in esame il materiale edilizio emerso nelle campagne di scavo condotte presso il complesso residenziale individuato presso la Piazza d'Arm
A job-shop problem with one additional resource type
No full textWe consider a job-shop scheduling problem with n jobs and the constraint that at most p < n jobs can be processed simultaneously. This model arises in several manufacturing processes, where each operation has to be assisted by one human operator and there are p (versatile) operators. The problem is binary NP-hard even with n = 3 and p = 2. When the number of jobs is fixed, we give a pseudopolynomial dynamic programming algorithm and a fully polynomial time approximation scheme (FPTAS). We also propose an enumeration scheme based on a generalized disjunctive graph, and a dynamic programming-based heuristic algorithm. The results of an extensive computational study for the case with n = 3 and p = 2 are presented
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