bluuebunny/crossref_metadata_2025 huggingface dataset:
Indoctrination, Moral Instruction, and Nonrational Beliefs: A Place for Autonomy?
Authors: Merry Michael S.
Published: August 2010

The manner in which individuals hold various nonevidentiary beliefs is critical to making any evaluative claim regarding an individual's autonomy. In this essay, I argue that one may be both justified in holding nonrational beliefs of a nonevidentiary sort while also being capable of leading an autonomous life. I defend the idea that moral instruction, including that which concerns explicitly religious content, may justifiably constitute a set of commitments upon which rationality and autonomy are dependent. I situate this discussion against the backdrop of a minimalist notion of autonomy. I then consider the case for nonrational beliefs, examining the difference between those whose content is objectionable on evidentiary grounds and those that are immune to verification. Next, I consider the indoctrination/moral instruction distinction through examining the various ways in which indoctrination is defined. I also consider the role that value coherence plays in shaping our identities, paying particular attention to fundamental commitments as defined by our respective families, cultures, and communities. Finally, I argue that individual psychology is central to our ability to assess the outcome of an upbringing purported to be indoctrinatory, and I emphasize the important role that experience and agency play in enabling us to evaluate our beliefs.
EDUCATING COMMUNAL AGENTS: BUILDING ON THE PERSPECTIVISM OF G.H. MEAD
Authors: Martin Jack
Published: August 2010

Abstract In their search for more communal forms of agency that might guide education, contemporary educational psychologists have mostly neglected the theorizing of George Herbert Mead. In this essay, Jack Martin aims to remedy such oversight by interpreting Mead’s social‐psychological and educational theorizing of selfhood and agency through the lenses of the perspectival realism Mead developed in the last decade of his life. This interpretation understands education as concerned with the cultivation and coordination of cultural, societal, interpersonal, and personal perspectives. Within this framework, communal agency is understood as a self‐interpreting, self‐determining capability of persons. This agentive capability derives from immersion and participation with others within sociocultural practices and perspectives, but also includes reactivity to those same practices and perspectives. The education of communal agents as envisioned here emphasizes the social nature of education, students’ experience and development, and the critical role of the teacher as a mediator between student development and social process. Such an education is grounded in the immediate experiences and perspectives of learners, but increasingly assists learners to move beyond their own experiences through engaged interaction with others and with resources for acquiring broader, more organized perspectives on themselves, others, and the world.
WHITE COMPLICITY AND SOCIAL JUSTICE EDUCATION: CAN ONE BE CULPABLE WITHOUT BEING LIABLE?
Authors: Applebaum Barbara
Published: August 2010

Abstract In part of an ongoing study of white complicity, moral responsibility, and moral agency in social justice education, Barbara Applebaum asks in this essay what model or models of moral responsibility can help white students recognize their white complicity and which models of moral responsibility obscure such acknowledgment. To address this question, she explores the concept of white complicity and its relation to racism and raises some compelling conceptual and pedagogical questions. Then she reviews a recent analysis of the concept of “complicity” and shows it to be inadequate as a foundation for white complicity. Finally, Applebaum describes Iris Marion Young’s conception of a Social Connection Model of Responsibility and shows it to be capable not only of elucidating white complicity but also, when incorporated in social justice pedagogy, of diminishing denials of white complicity by white students.
Evaluation of Quality of Life and Sexual Satisfaction in Women Suffering from Chronic Pelvic Pain With or Without Endometriosis
Authors: Tripoli Tatiana M. , Sato Hélio , Sartori Marair G. , de Araujo Fábio Fernando , Girão Manoel J.B.C. , Schor Eduardo
Published: August 2010

Introduction

Chronic pelvic pain (CPP) is one of the most frequent symptoms in women of reproductive age. This is an enigmatic clinical condition that results from the complex interactions of physiological and psychological factors with direct impact on the social, marital, and professional lives of women.

Aim

To evaluate the quality of life and sexual satisfaction of women who suffer from CPP with or without endometriosis.

Method

Forty-nine patients who had been diagnosed with endometriosis and 35 patients with CPP diagnosed with another gynecological condition, all 84 of whom were treated at the Chronic Pelvic Pain and Endometriosis Clinic at Universidade Federal de São Paulo (UNIFESP) from January to July of 2008. The controls were 50 healthy women from the Family Planning Clinic at UNIFESP.

Main Outcome Measures

World Health Organization Quality of Life Assessment-Bref (WHOQOL-BREF) quality of life questionnaire and the Golombok-Rust Inventory of Sexual Satisfaction (GRISS).

Results

No statistically significant differences were observed between the groups with CPP symptoms, in either the results from the WHOQOL-BREF or in the GRISS questionnaire. In both questionnaires, differences were observed when the two groups of symptomatic women were compared with the group of healthy women.

Conclusion

CPP caused by endometriosis or other gynecological conditions leads to a significant reduction of quality of life and sexual satisfaction.
Prostate-Specific Antigen Levels are Associated with Arterial Stiffness in Essential Hypertensive Patients
Authors: Vyssoulis Gregory , Karpanou Eva , Kyvelou Stella-Maria , Vlachopoulos Charalambos , Tzamou Vanessa , Stefanadis Christodoulos
Published: August 2010

Introduction

Prostate-specific antigen (PSA) has been recently related to cardiovascular system in a multifactorial way. Arterial stiffness is a independent predictor of cardiovascular events and is involved in the pathogenesis of hypertension. The aim of the present study was to investigate whether PSA values, are associated with arterial stiffness indices in patients with essential arterial hypertension.

Methods

The study comprised 150 consecutive male patients (mean age 60 years) with uncomplicated never-treated essential hypertension. All patients underwent a complete clinical and laboratory evaluation, including measurement of PSA levels. Aortic stiffness and arterial wave reflection assessment was made by using carotid-femoral (PWVc-f) pulse wave velocity and aortic augmentation index corrected for heart rate (AIx75). Patients with prostate cancer or benign prostate hyperplasia (PSA > 4 ng/mL) were excluded from the study.

Results

PSA was positively associated with waist-to-hip ratio (r = 0.235, P = 0.04), PWVc-f (r = 0.426, P < 0.001), AIx75 (r = 0.264, P = 0.001), and high sensitivity C-reactive protein (hsCRP; r = 0.376, P < 0.001). In categorization to PSA quartiles, patients in the higher quartile presented with higher waist-to hip ratio (P = 0.009), PWVc-f (P < 0.00001), AIx75 (P < 0.001) and hsCRP (P < 0.001) values. In multivariate analysis after adjustment for various confounders PSA remained a significant determinant of PWVc-f values (beta [SE] = 0.477 [0.13], R2 = 0.405, P < 0.001).

Conclusion

The present study points towards an association between PSA levels and aortic stiffness in untreated essential hypertensive males. Potential causal relationships between PSA and arterial stiffness remain to be further explored.
Sexual Function in Obese Women with and without Binge Eating Disorder
Authors: Castellini Giovanni , Mannucci Edoardo , Mazzei Chiara , Lo Sauro Carolina , Faravelli Carlo , Rotella Carlo M. , Maggi Mario , Ricca Valdo
Published: August 2010

Introduction

Binge eating disorder (BED) is highly prevalent among individuals seeking treatment for obesity. No controlled studies assessing the sexual functioning of these patients have been published so far.

Aim

To investigate the sexual functioning of a clinical sample of obese women affected by BED, comparing them with obese non-BED patients (Ob), and with normal weight controls.

Methods

A consecutive series of 107 obese BED and 110 obese non-BED patients referring for the first time to the Clinic for Obesity of the University of Florence, together with a control group of 92 normal weight subjects, were studied.

Main Outcome Measures

Patients were studied by means of the Structured Clinical Interview for DSM-IV and the Female Sexual Function Index (FSFI). Moreover, several self-reported questionnaires assessing the eating specific and general psychopathology were used.

Results

BED and obese non-BED probands reported a lower sexual activity compared to controls, in terms of absence of sexual intercourse rate, and sexual intercourse frequency. BED patients showed lower FSFI total and subscales scores compared to Ob, and Ob probands reported lower scores compared to controls. According to the multiple linear regression analysis, emotional eating was the main determinant of FSFI scores (FSFI total score, desire, arousal, lubrication, orgasm, satisfaction) for both BED and Ob patients, while impulsivity (inversely associated with FSFI total, orgasm, and pain) and shape concern (inversely associated with arousal, lubrication, orgasm) were main determinants for BED patients only.

Conclusions

BED patients, compared to obese non-BED and controls, have worse sexual functioning, which is associated with high levels of emotional eating, impulsivity, and shape concerns. The relationship between sexual functioning and eating psychopathology should be carefully addressed in obese patients with and without BED.
A new allele, HLA‐B*4212, identified in a Brazilian volunteer bone marrow donors by sequence‐based typing
Authors: Mattar S. B. , Uehara C. J. S. , Ribas F. , Vargas R. G. , Wowk P. F. , Poerner F. , Bicalho M. G.
Published: August 2010

Here we report the discovery of a novel HLA‐B allele, named B*4212 in a Brazilian volunteer bone marrow donor. The new sequence has nucleotide variation at position 496 (T→G) as compared with B*4201. This variation results in a conservative amino acid substitution from valine to glycine at codon 165 of exon 3.
Terpenoid profiles of in vitro regenerated Artemisia petrosa subsp. eriantha (Apennines' genepì)*
Authors: Pace Loretta , Grandi Silvia , Marotti Mauro , Piccaglia Roberta , Pacioni Giovanni , Spanò Laura
Published: August 2010

Artemisia petrosa subsp. eriantha is a protected species whose essential oil is of great interest mainly for liqueur industry; it was micropropagated by in vitro culture technique followed by transfer to field. The content and the characteristics of the essential oils from regenerated plants collected after 1 and 2 years of field growing and from regenerated plants grown ‘in situ’ were assessed by gas chromatography/mass spectrometry (GC/MS) and compared with those of wild plants. Results indicate that in vitro propagated plants produce oils rich in sesquiterpenes. Forty seven compounds were identified, the main constituents being α‐ and β‐thujone, whose content increased with the plant age. Quantitative, but not qualitative variations were observed both in wild and in micropropagated plants in relation with plant age and environmental factors. Thus, micropropagation provides plants suitable for the industrial exploitation of this species.
Ceratal autotomy and regeneration in the aeolid nudibranch Phidiana crassicornis and the role of predators
Authors: Miller Jennifer A. , Byrne Maria
Published: August 2010

Abstract. Ceratal autotomy by the aeolid nudibranch Phidinna crassicornis is common in the field and was induced in the laboratory by mechanical and predatory stimuli. The ceras detaches from the body wall along an autotomy plane located at its basal constriction. Cerata released copious amounts of mucus during autotomy and exhibited a prolonged writhing response that continued for several hours after detachment. Regeneration of cerata autotomized in the field and in the laboratory was documented. Four days after autotomy, regenerating cerata appeared as small protuberances. By day 24 the regenerates acquired their mature structural organisation and vivid colour. The cerata subsequently increased in length and diameter and were indistin‐guishable from surrounding cerata by 41 to 43 days after autotomy. Regeneration rates of cerata induced to autotomize in the laboratory and regeneration of cerata autotomized in the field were similar, averaging 0.08 and 0.067 mdday, respectively. The sequence of morphological events involved with regeneration following experimental and natural induction of autotomy was identical. The kelp crab Pugettia productn induced autotomy by holding cerata with its chelae. This crab also fed on autotomized cerata and consumed locomotory and ceratal mucus. Ceratal autotomy may be an important mechanism of escape from this predatory crustacean. Other potential predators including hermit crabs and tidepool sculpins did not elicit defensive behaviour in P. crussicornis. Nematocysts were present in the enidosacs and their role in defense was investigated. Fired nematocysts were observed in podia of the asteroid Crossaster papposus following ceratal contact but were not seen in the podia of Pycnopodia helianthoides in a similar trial. For P. crassicornis, the cnidosacs may function primarily as a storage device for safe sequestering of nematoeysts that could pose a threat to the digestive system. They did not play a major defensive role against the predators tested, but may be important in the field against other predators.
Reorganization of the nervous system during metamorphosis of a hydrozoan planula
Authors: Martina Vicki J.
Published: August 2010

Abstract. Laser scanning confocal microscopy is used to reveal the changes that occur in the RFamide‐positive nerve net as a free‐swimming, solid hydrozoan planula larva is transformed into a sessile, hollow, young polyp. Seven stages of development in Pennaria tiarella are described: planula competent to metamorphose, attaching planula, disc, pawn, crown, developing polyp, and developed primary polyp. The RFamide‐positive nervous system undergoes dramatic reorganization during metamorphosis: (1) larval neurons degenerate; (2) new neurons differentiate and reform a nerve net; and (3) the overall distribution pattern of the nervous system changes. This study confirms earlier observations on RFamide‐positive neurons of Hydractinia which also show the loss of these cells after the onset of metamorphosis.
Ultrastructure of the ovary and oogenesis in six species of patellid limpets (Gastropoda: Patellogastropoda) from South Africa
Authors: Hodgson Alan N. , Eckelbarger Kevin J.
Published: August 2010

Abstract. The ultrastructural features of the ovary and oogenesis have been described in 6 species of patellid limpets from South Africa. The ovary is a complex organ that is divided radially into numerous compartments or lacunae by plate‐like, blind‐ended, hollow trabeculae that extend from the outer wall of the ovary to its central lumen. Trabeculae are composed of outer epithelial cells, intermittent smooth muscle bands, and extensive connective tissue. Oocytes arise within the walls of the trabeculae and progressively bulge outward into the ovarian lumen during growth while partially surrounded by squamous follicle cells. During early vitellogenesis, the follicle cells lift from the surface of the underlying oocytes and microvilli appear in the perivitelline space. Follicle cells restrict their contact with the oocytes to digitate foot processes that form desmosomes with the oolamina. When vitellogenesis is initiated, the trabecular epithelial cells hypertrophy and become proteosynthetically active. Yolk synthesis involves the direct incorporation of extraoocytic precursors from the lumen of the trabeculae (hemocoel) into yolk granules via receptor‐mediated endocytosis. Lipid droplets arise de novo and Golgi complexes synthesize cortical granules that form a thin band beneath the oolamina. A fibrous jelly coat forms between the vitelline envelope and the overlying follicle cells in all species.
Sense organs and central nervous system in an enigmatic terrestrial polychaete, Hrabeiella perighndulata (Annelida)–implications for annelid evolution
Authors: Purschke Günter
Published: August 2010

Abstract. The terrestrial polychaete Hrabeiella periglandulata has many features in common with the Clitellata and the polychaete taxon Parergodrilidae. An ultrastructural investigation of the central nervous system and the sense organs of H. periglandulata individuals was undertaken to look for structural similarities with these taxa as well as to elucidate whether these structures might exhibit adaptive characters typical of terrestrial annelids in general. The central nervous system of H. periglandulata is subepidermal and consists of a brain situated in the first achaetigerous segment. The circumoesophageal connectives are without dorsal and ventral roots, and the ventral nerve cord has closely associated connectives and ill‐defined ganglia. In contrast to clitellates and the terrestrial parergodrilid Parergodrilus heideri, nuchal organs are present. They are internal and highly modified compared with those of marine polychaetes but are similar to those of the intertidal parergodrilid Stygocapitella subterranea. A pair of ciliary sense organs is present inside the brain, resembling similar structures in many microdrile oligochaetes. These observations indicate that there are, in fact, structural similarities between the nervous system and the sense organs of clitellates, parergodrilids, and Hrabeiella individuals. These similarities may very likely be the result of convergent evolution in adaptation to the terrestrial environment.
Immunocytochemical evidence for biogenic amines and immunogold labeling of serotonergic synapses in tentacles of Aiptasia pallida (Cnidaria, Anthozoa)
Authors: Westfall Jane A. , Elliott Scott R. , MohanKumar P.S. , Carlin Ryan W.
Published: August 2010

Abstract. Evidence for classical neurotransmitters in sea anemones remains controversial. We used high performance liquid chromatography with electrochemical detection (HPLC‐EC) and electron microscopical imunocytochemistry to determine the presence of serotonin and precursor synthetic enzymes of other biogenic amines in tentacles of the sea anemone Aiptasia pallida. Using HPLC‐EC we found dopamine and serotonin (5‐hydroxytryptamine, 5‐HT) in both tentacles and whole animal homogenates. Antibodies to tyrosine hydroxylase, dopamine β‐hydroxylase, phenylethanolamine N‐methyltransferase, and 5‐HT were used with the peroxidase‐antiperoxidase method to reveal positive immunoreactivity to these substances in neurons of tentacles. Immunogold labeling of serial thin sections with the anti‐5–HT antibody revealed reactive products in synaptic vesicles at interneuronal, neuromuscular, and neurospirocyte synapses. These results suggest that both catecholamine and indolamine neurotransmitters occur in sea anemones in addition to the neuropeptide Antho‐RFamide, indicating the presence of multiple types of transmitter substances in an early nervous system.
Predation on kamptozoans (Entoprocta)
Authors: Canning Martha Hill , Carlton James T.
Published: August 2010

Abstract. Predation on kamptozoans (phylum Kamptozoa = Entoprocta) is not mentioned in any literature on the phylum. We have found a plagiostomid turbellarian flatworm (Plagios‐tomum sp.) preying upon Barentsia benedeni in an estuarine sublittoral fouling community in Long Island Sound, USA. Previous records of predation on kamptozoans by nudibranch opis‐thobranchs (sea slugs) are reviewed. Predation on kamptozoans by some members of two phyla, Mollusca and Platyhelminthes, is thus now known.
Heydenius araneus n.sp. (Nematoda: Mermithidae), a parasite of a fossil spider, with an examination of helminths from extant spiders (Arachnida: Araneae)
Authors: Poinar George
Published: August 2010

Abstract. A mermithid, a parasite of a spider (Araneae: Thomisidae) in Baltic amber (40 mya), is described as Heydenius araneus n.sp. (Nematoda: Mermithidae) and represents the first fossil record of a nematode parasite of an arachnid. After a critical examination of reports of naturally occurring helminths of extant spiders, I conclude that although mermithid parasitism is well established in this host group, previous reports of hairworm parasites of spiders are “nomina dubia,” putative records, or refer to mermithid nematodes.
The auricularia‐to‐doliolaria transformation in two aspidochirote holothurians, Holothuria mexicana and Stichopus californicus
Authors: Lacalli Thurston C. , West Jenifer E.
Published: August 2010

Abstract. The fragmentation and rearrangement of the ciliary bands that occurs during the auricularia‐to‐doliolaria transformation is described for the non‐feeding auricularia larva of Holothuria mexicana and the more typical planktotrophic auricularia of Stichopus californicus. The ciliary band of the auricularia larva runs along a series of ridges that project from the sides of the body. Fragmentation results from a loss of ciliary band cells from the zones between the ridges. The remaining fragments then reorient, elongate, and fuse to form the 5 circumferential bands of the doliolaria. The fate of the band cells lost during this process could not be determined with certainty, but they disappear after being sequestered beneath the epithelium for a time, probably through histolysis. Cell counts indicate that significant numbers of cells are also lost from the ridges. Normal swimming ceases just before transformation begins, probably because the nerve supply to all or parts of the band is disrupted, and this may play a role in initiating morphogenesis.
Hooked setae: tests of the anchor hypothesis
Authors: Merz Rachel A. , Woodin Sarah A.
Published: August 2010

Abstract. We tested the hypothesis that hooked setae function as anchors in three species of tubiculous polychaetes (Eudistylia vancouveri, Schizobranchia insignis, and Owenia fusiformis). All maintained position within their tubes when exposed to high pressures (up to 100–200 kPa) applied from the posterior direction (where it would tend to cause the tips of hooks to embed in the tube wall). When pressure was applied in the opposite direction, where hooks would not tend to embed in the tube wall, the worms were expelled from their tubes at lower pressures (30–100 kPa). The ability of these worms to maintain their position within their tubes was independent of body size. On the basis of these findings we made three predictions. First, worms that use their hooked setae as anchors should have those hooks located on the body in greatest number and size on the segments associated with greatest worm diameter. Second, as worms increase in size, setal armory should increase in a predictable way. The force that can be applied to extract worms from their tubes by suction feeding fish or wave action would increase as the area subject to suction increases (proportional to the cross sectional area of the tube). Therefore, we predict that setal armory should also increase as a squared function. Third, hooks or uncini should show patterns of wear or loss and/or the worms' bodies should show scars or wounds where the setae are most used (e.g., where worm diameter is at its maximum). All of these predictions were supported by the data and indicate that hooked setae function as anchors for tubiculous polychaetes. This is important for understanding the biology of these animals and has implications for using hooked setae as characters in phylogenetic analyses.
Ultrastructure of the statocyst of the marine enchytraeid Grania americana (Annelida: Clitellata)
Authors: Locke Jan M.
Published: August 2010

Abstract. The enchytraeid Grania americana has a dorsal statocyst within the peristomium. It is connected to the anterior end of the cerebral ganglion. Transmission electron and light microscopy were used to study this region of the head. The statocyst is divided into four membrane‐bound chambers; each contains an electron dense statolith surrounded by numerous sensory cilia, so that it is a multi‐chambered or compound statocyst. Cilia within the statocyst possess a 9 × 2 + 0 microtubule arrangement, with one of the doublets in a central position. All cilia that were observed in the statocyst and in the cerebral ganglion had this arrangement of microtubules. This is the first description of a statocyst in the Clitellata. The statocyst of G. americana is compared to those described in polychaetes and may provide useful information for phylogenetic and taxonomic studies of the genus, of clitellates, and of annelids.
The structure of the bursa copulatrix in virgin and mated snails, Helisoma duryi (Mollusca): role of acid phosphatase in reproduction
Authors: Clelland Eric , Renna Tania Di , Saleuddin A.S.M.
Published: August 2010

Abstract. The fine structure of the bursa copulatrix of the virgin snails has been compared with that of mated snails. One of the noticeable changes after mating is an increase in the number of the Golgi and the secretory vesicles. Since some of the vesicles react positively for acid phosphatase it is suggested that this enzyme activity increases following mating. The bursa lumen of the virgin snail contains gel‐like materials devoid of spermatozoa, however, following mating, the lumen is full of semen containing live spermatozoa and bacteria. The source of bacteria in the lumen is not known. Acid phosphatase activity is significantly higher in the luminal content of mated snails than in the virgin snails. The activity is higher in the lumen than in the epithelial cells, suggesting that the enzyme is secreted into the lumen where it is utilized for extracellular degradation of spermatozoa. Following mating, the spermatozoa are motile in the lumen of the bursa for ∼3–7 d, but become immobile and finally undergo extracellular digestion so that intact spermatozoa are not recognizable by day 10. The use of castrated snails in mating experiments suggest that individuals of Helisoma duryi reproduce by cross fertilization and that the bursa may act as the holding organ from where the spermatozoa are periodically transported to the carrefour over ∼7 d. At day 10 following mating, however, autosperms appear in the hermaphroditic duct awaiting the next mating.
Mud crabs (Xanthidae) in Chesapeake Bay: claw characteristics and predation on epifaunal bivalves
Authors: Milke Lisa M. , Kennedy Victor S.
Published: August 2010

Abstract. We examined claw characteristics of mud crabs (Eurypanopeus depressus, Rhithropanopeus harrisii) to determine if one crab species was potentially more powerful than the other. We related our findings to the abilities of individuals of each species to open epifaunal mytiliform bivalves (Ischadium recurvum; Mytilopsis leucophaeata) that occur on beds of eastern oysters (Crassostrea virginica) in mesohaline Chesapeake Bay. There were high correlations between claw width or height and claw length, and between claw length and carapace width for both mud crab species. The mechanical advantage or “grip strength’ of the crusher and cutter claws of both species did not change with crab size (carapace width) and did not differ between sexes in each species, nor did the cutter data differ between species. However, individuals of E. depressus had a significantly stronger crusher claw grip than did those of R. harrisii. Data on mechanical advantage for both species were similar to values reported in the literature for members of other xanthid crab species. These values in turn overlapped those reported for calappid, cancrid, majid, and grapsid crabs, and were greater than those of various species of portunid crabs and individual species of fiddler crab, lobster, crayfish, and ghost shrimp. When simultaneously presented with the two species of bivalves, the mud crabs E. depressus chose mussels of M. leucophaeata first and crabs of R. harrisii chose mussels of I. recurvum first about two‐thirds of the time; ultimately, the crabs ate both bivalve species in >50% of the choice experiments. The size range in E. depressus was greater than that in R. harrisii, and crabs of E. depressus opened larger bivalves than did crabs of R. harrisii, although similar‐sized individuals of the two crab species overlapped in their ability to open bivalves of both species. In Mytilopsis leucophaeata, there is probably no size refuge from predation by the mud crabs whereas the larger mussels of I. recurvum do have a refuge in size.
New model for the formation and function of sagittocysts: Symsagittifera corsicae n. sp. (Acoela)
Authors: Gschwentner Robert , Baric Sanja , Rieger Reinhard
Published: August 2010

Abstract. This study is focused on the formation and function of sagittocysts, which are secretions typical of members of the acoel family Sagittiferidae. The needle‐shaped sagittocysts are produced in specialized gland cells (sagittocytes) whose distal necks are often surrounded by muscle mantles. Contraction of the muscle mantle ejects the sagittocyst. We establish a model for the development of sagittocytes and muscle mantles out of the stem cell pool of the new acoel species Symsagittifera corsicae. We used various techniques, especially interference and phase‐contrast microscopy of living specimens as well as labeling of the body‐wall musculature, for species characterization. In addition to the morphological features, we provide the third complete sequence of the 18S rDNA gene in the family Sagittiferidae.
Are the two physiological races of Pollicipes polymerus (Cirripedia) genetically divided along the California coast?
Authors: Miner Benjamin G.
Published: August 2010

Abstract. Genetic work on numerous species with planktonically dispersing larvae has demonstrated gene flow throughout populations along the California coast, despite steep environmental gradients around Point Conception. Previous ecological work on a planktonically dispersing intertidal barnacle, Pollicipes polymerus, demonstrated that this species is divided into two physiological races near Point Conception, at Point Latigo. The northern race broods when water temperature either warms or cools to 14°C and the southern race broods as water warms to 20°C. I examined 8 polymorphic allozyme loci from five populations between Santa Cruz and San Diego to test if the two physiological races are genetically divided. No genetic differences were found over this geographic range, supporting a previous molecular study. These results suggest that reproductive differences between the two races of this stalked barnacle may result from plasticity in brooding activity.
Embryogenesis and metamorphosis in a haplosclerid demosponge: gastrulation and transdifferentiation of larval ciliated cells to choanocytes
Authors: Leys Sally P. , Degnan Bernard M.
Published: August 2010

Abstract. Early development and metamorphosis of Reniera sp., a haplosclerid demosponge, have been examined to determine how gastrulation occurs in this species, and whether there is an inversion of the primary germ layers at metamorphosis. Embryogenesis occurs by unequal cleavage of blastomeres to form a solid blastula consisting micro‐ and macromeres; multipolar migration of the micromeres to the surface of the embryo results in a bi‐layered embryo and is interpreted as gastrulation. Polarity of the embryo is determined by the movement of pigment‐containing micromeres to one pole of the embryo; this pole later becomes the posterior pole of the swimming larva. The bi‐layered larva has a fully differentiated monociliated outer cell layer, and a solid interior of various cell types surrounded by dense collagen. The pigmented cells at the posterior pole give rise to long cilia that are capable of responding to environmental stimuli. Larvae settle on their anterior pole. Fluorescent labeling of the monociliated outer cell layer with a cell‐lineage marker (CMFDA) demonstrates that the monociliated cells resorb their cilia, migrate inwards, and transdifferentiate into the choanocytes of the juvenile sponge, and into other amoeboid cells. The development of the flagellated choanocytes and other cells in the juvenile from the monociliated outer layer of this sponge's larva is interpreted as the dedifferentiation of fully differentiated larval cells—a process seen during the metamorphosis of other ciliated invertebrate larvae—not as inversion of the primary germ layers. These results suggest that the sequences of development in this haplosclerid demosponge are not very different than those observed in many cnidarians.
Ultrastructure of the tentacle nerve plexus and putative neural pathways in sea anemones
Authors: Westfall Jane A. , Elliott Carol F.
Published: August 2010

Abstract. Neurons of sea anemone tentacles receive stimuli via sensory cells and process and transmit information via a plexus of nerve fibers. The nerve plexus is best revealed by scanning electron microscopy of epidermal peels of the tentacles. The nerve plexus lies above the epidermal muscular layer where it appears as numerous parallel longitudinal and short interconnected nerve fibers in Calliactis parasitica. Bipolar and multipolar neurons are present and neurites form interneuronal and neuromuscular synaptic contacts. Transmission electron microscopy of cross sections of tentacles of small animals, both C. parasitica and Aiptasia pallida, reveals bundles of 50–100 nerve fibers lying above groups of longitudinal muscle fibers separated by intrusions of mesoglea. Smaller groups of 10–50 slender nerve fibers are oriented at right angles to the circular muscle formed by the bases of the digestive cells. The unmyelinated nerve fibers lack any glial wrapping, although some bundles of epidermal fibers are partially enveloped by cytoplasmic extensions of the muscle cells; small gastrodermal nerve bundles lie between digestive epithelial cells above their basal myonemes. A hypothetical model for sensory input and motor output in the epidermal and gastrodermal nerve plexuses of sea anemones is proposed.
Ciliary filter‐feeding structures in adult and larval gymnolaemate bryozoans
Authors: Nielsen Claus
Published: August 2010

Abstract. Ciliary filter‐feeding structures of gymnolaemate bryozoans—adults of Flustrellidra hispida and Alcyonidium gelatinosum, larvae of Membranipora sp.—were studied with SEM. In F. hispida and A. gelatinosum, the distal part of each tentacle has a straight row of stiff laterofrontal cilia which carry out “ciliary sieving” to capture suspended food particles that are subsequently transported downward towards the mouth by tentacle flicking; both structure and function resemble those of stenolaemate tentacles. The proximal part of the tentacle and of the ciliary ridge of a cyphonautes larva have strikingly similar structures, except that the laterofrontal cells are monociliate in the adults and biciliate in the larvae. The laterofrontal cells of the tentacles are arranged in a zigzag row and their cilia form two parallel rows, a frontal and a lateral row. The latter probably forms the sieve of stiff filter cilia in front of the water‐pumping lateral cilia, whereas the frontal row appears to be held close to the frontal ciliary band of the tentacle. The biciliate laterofrontal cells of the cyphonautes larva have the cilia arranged in similar rows. The detailed morphological similarities between the ciliary bands of adult and larval filtering structures suggest that the feeding mechanisms are similar, contrary to what has been previously thought.
Life history of Littorina scutulata and L. plena, sibling gastropod species with planktotrophic larvae
Authors: Hohenlohe Paul A.
Published: August 2010

Abstract. The intertidal, sibling species Littorina scutulata and L. plena (Gastropoda, Proso‐branchia) are sympatric throughout most of their ranges along the Pacific coast of North America. Both species release disc‐shaped, planktonic egg capsules from which planktotrophic veliger larvae hatch. Here I review existing data and present new observations on these species' life history, including age at first reproduction, spawning season, maximum fecundity rates, capsule morphology, egg size and number, pre‐hatching development, larval growth at three food concentrations, potential settlement cues, planktonic period, and protoconch size. Previous classification of egg capsule morphologies used to distinguish the species is inaccurate; instead, capsules can be categorized into three types of which each species may produce two. Females of L. scutulata produced capsules with either two rims of unequal diameter or one rim, while females of L. plena produced capsules with one rim or two rims of nearly equal diameter. Females of each species spawned sporadically from early spring to early fall in Puget Sound. Larvae of L. plena hatched one day earlier than those of L. scutulata, and both species grew fastest in the laboratory at intermediate food concentrations. Larvae metamorphosed in the presence of a variety of materials collected from their adult habitat, including conspecific adults, algae, rocks, and barnacle tests. This is the first report of planktotrophic larvae in this genus metamorphosing in the laboratory. The total planktonic period of 8 larvae of L. scutulata raised in the laboratory was 37–70 days, and a single larva of L. plena metamorphosed after 62 days. Protoconch diameter of shells collected from the field was 256–436 μm and did not differ significantly between the species. Previous allozyme and mitochondrial DNA work has suggested high levels of genetic variability in both species and greater genetic population structure in L. plena, despite the long spawning season and long‐lived larvae in both species. The interspecific life history differences described here appear insufficient to produce consistent differences in gene flow patterns.
Reproduction and simultaneous hermaphroditism inBranchiomma luctuosum(Polychaeta, Sabellidae) from the Mediterranean Sea
Authors: Licciano Margherita , Giangrande Adriana , Gambi Maria Cristina
Published: August 2010

Abstract.Previous observations on the reproductive biology and gametogenesis ofBranchiomma luctuosum(Polychaeta: Sabellidae) were extended in this study, with a description of larval development and of reproduction at the population level, comparing populations from the Tyrrhenian Sea (Ischia, Naples) and Ionian Sea (Gulf of Taranto). AlthoughB. luctuosumis a simultaneous hermaphrodite, producing both male and female gametes in each fertile segment, present observations seem to preclude self‐fertilization. Both gametes were spawned under laboratory conditions, and broadcasting was confirmed by sperm structure, which appears adapted for external fertilization. Larval development revealed the shortest pelagic period known for sabellids of similar size and life history. Oogenesis was prolonged and extraovarian. The Ionian population seemed to have a resting period during which eggs, having already begun vitello‐genesis, remained at a diameter of about 30 μm. After this period, rapid growth was observed: the oocytes reached maximum diameter (140 μm) in about 2 months. The spawning period began earlier and lasted longer in the Ionian population, compared to the Tyrrhenian population. This pattern seems to be due to asynchronous vitellogenesis within individuals. Documenting the reproductive features of this species will help us to understand its role as a primary colonizer, since hermaphroditism and a short pelagic phase may produce high population densities starting from only a few individuals.
Life history of the oligochaeteEnchytraeus coronatus(Annelida, Enchytraeidae) in agar culture
Authors: Rodriguez Pilar , Arrate Jesus A. , Martinez‐Madrid Maite
Published: August 2010

Abstract.Life‐history attributes and the reproductive biology ofEnchytraeus coronatus(Oligochaeta, Enchytraeidae) were studied in agar cultures, as a basis for using this species in toxicity tests and other experimental studies. The use of agar allows daily examination of the behavior, reproduction, and mortality of the worms. At 20°C,E. coronatushad a generation time of 21–22 days and an embryonic period of 7–10 days. Hatch rate was high (>80%) and worms became sexually mature 8–10 days after hatching. Cocoon production and number of eggs per cocoon were positively correlated. Mortality in the first stages of the life cycle (embryonic period and first week after hatching) was about 38%. Three different periods of cocoon production were distinguished: a period characterized by a regular increase in the number of cocoons produced (weeks 4–9), a period of production at a constant high rate of ∼5 cocoons per week (weeks 10–20), and a period of decline in production rate (weeks 21–32), down to a mean value of 1.6 cocoons per adult in the last week. This study showed that synchronized agar cultures of cohorts can provide adults for long‐term experimental tests, with the age for optimum reproduction being 8–20 weeks.
Apoptotic‐like morphology is associated with annual synchronized death in kleptoplastic sea slugs (Elysia chlorotica)
Authors: Mondy William L. , Pierce Sidney K.
Published: August 2010

Abstract. Certain digestive cells of the opisthobranch mollusc, Elysia chlorotica, contain functional chloroplasts which they steal from the filamentous alga, Vaucheria litorea. The adult portion of the life cycle of the slug lasts for ∼10 months and is completely synchronized among individuals. All the adults die each year within a few weeks of each other. We have examined the microscopic morphology of the slugs near the end of the life cycle. Light microscopy demonstrated an absence of chloroplasts in most of the digestive epithelial cells, the appearance of many crypt cells containing residual bodies and an invasion of the blood sinuses by neoplastic morula‐like cells as the animals die. Electron microscopy revealed a degeneration of the digestive diverticulum which had several morphological characteristics in common with apoptosis: expansion of the endoplasmic reticulum and Golgi apparatus, DNA fragmentation, formation of primary lysosomes, and condensation of chromatin. These are followed by fragmentation of the nucleus and cytoplasm into autosomes merging to form a large central autolysosome. In addition in the aging slugs, the plastids begin to degenerate until none were left in the digestive epithelial cells and the central autolysosome contained numerous viral particles.
Description of intracerebral ocelli in two species of North American crayfish:Orconectes limosus(Cambaridae) andPacifastacus leniusculus(Astacidae)
Authors: Bobkova Marina , Grève Pierre , Meyer‐Rochow V. Benno , Martin Gilbert
Published: August 2010

Abstract.Among malacostracan crustaceans, intracerebral ocelli were first discovered in Isopoda, but they have been more recently reported from a crayfish (Cherax destructor) and a sandhopper (Talitrus saltator). This electron microscopic study increases the number of crayfish taxa in which intracerebral ocelli are now known to occur by two: Astacidae and Cambaridae. These photoreceptors are always integrated into the anteromedio‐dorsal part of the brain and are not visible externally. Each ocellus is made up of 4–5 photoreceptor cells and is characterized by the presence of a fused rhabdom. The occurrence of different kinds of lysosomes in the cytoplasm is indicative of metabolic activity and perhaps membrane turnover. One typical feature of crayfish ocelli is their extraordinary variability in number. This trait is exemplified by individuals ofPacifastacus leniusculus, where as many as 14 ocelli were identified in a single brain. The arrangement of the ocelli is often not symmetrical with regard to the brain's midline and the ocelli always lack dioptric structures. Thus, it is difficult to see how they are involved in image formation. However, further research is needed to determine the precise role of these “hidden” receptors.
Larval development in the Homoscleromorpha (Porifera, Demospongiae)
Authors: Boury‐Esnault Nicole , Ereskovsky Alexander , Bézac Chantal , Tokina Daria
Published: August 2010

Abstract. Embryonic development from coeloblastula to fully developed larva was investigated in 8 Mediterranean homoscleromorph species: Oscarella lobularis, O. tuberculata, O. microlobata, O. imperialis, Plakina trilopha, P. jani, Corticium candelabrum, and Pseudocorticium jarrei. Morphogenesis of the larva is similar in all these species; however, cell proliferation is more active in species of Oscarella than in Plakina and C. candelabrum. The result of cell division is a wrinkled, flagellated larva, called a cinctoblastula. It is composed of a columnar epithelium of polarized, monoflagellated cells among which are scattered a few non‐flagellated ovoid cells. The central cavity always contains symbiotic bacteria. Maternal cells are also present in O. lobularis, O. imperialis, and P. jarrei. In the fully developed larva, cell shape and dimensions are constant for each species. The cells of the anterior pole have large vacuoles with heterogeneous material; those of the postero‐lateral zone have an intranuclear paracrystalline inclusion; and the flagellated cells of the posterior pole have large osmiophilic inclusions. Intercellular junctions join the apical parts of the cells, beneath which are other specialized cell junctions. A basement membrane underlying the flagellated cells lines the larval cavity. This is the first observation of a basement membrane in a poriferan larva. The basal apparatus of flagellated cells is characterized by an accessory centriole located exactly beneath the basal body. The single basal rootlet is cross striated. The presence of a basement membrane and a true epithelium in the larva of Homoscleromorpha—unique among poriferan clades and shared with Eumetazoa—suggests that Demospongiae could be paraphyletic.
Phylogenetic analysis of the mitochondrial cytochrome c oxidase subunit 1 gene from 13 sipunculan genera: intra‐ and interphylum relationships
Authors: Statona Joseph L.
Published: August 2010

Abstract. Sipunculans are a phylum of non‐segmented, marine worms. Although they are well characterized morphologically, relationships within the phylum and the relationship of Sipuncula to other spiralian phyla have been strongly debated. I analyzed representatives of 13 of 17 described genera using a 654‐bp fragment of the mitochondrial gene, cytochrome c oxidase subunit I, to construct the first intraphylum phylogenetic hypothesis for sipunculans based on molecular sequence data. Within the phylum, tree topologies are loosely congruent with a previously published morphological analysis, except that the monotypic genus Phascolopsis occurred within the Golfingiaformes as a sister group to, or nested within, the Themistidae. Phylogenetic analyses, including 30 sequences from additional invertebrate taxa, suggest that sipunculans are most closely related to the Annelida (including Echiura). A previously proposed sipunculan‐molluscan relationship is not supported. While not universally accepted, this hypothesis is consistent with other recent and past data on phylum‐level relationships.