bluuebunny/crossref_metadata_2025 huggingface dataset:
Hair Cell Orientation Patterns on the Saccules of Juvenile and Adult Toadfish, Opsanus tau
Authors: Edds‐Walton Peggy L. , Popper Arthur N.
Published: April 2010

Saccules from 10 adult (five female, five male) toadfish (Opsanus tau), 13.5–26 cm standard length, were examined for individual/sexual variation in the hair cell orientation pattern. In addition, saccules from two juveniles (5 and 6 cm standard length) were compared with those of the adults to determine whether maturational differences exist in the hair cell orientations. The hair cell orientation pattern is unlike any reported previously for this species or its congener, O. beta. There are no major differences between the hair cell orientations of males and females, nor between the juveniles and the adults. A slight individual variation is present in the proportion of hair cells oriented in a particular direction in a specific area of the sensory epithelium. Potential ramifications of this hair cell orientation pattern are discussed with regard to development and auditory processing.
The Ultrastructure of the Spermatozoa of Squamata—I. Scincidae, Gekkonidae and Pygopodidae (Reptilia)
Authors: Jamieson B. G. M. , Oliver S. C. , Scheltinga D. M.
Published: April 2010

Abstract Squamate autapomorphies seen in sperm of the Scincidae (e.g. Ctenotus robustus, Carlia pectoralis, Cryptoblepharus virgatus, and Lampropholis delicata) are penetration of the fibrous sheath of the axoneme into the midpiece, and the paracrystalline subacrosomal cone. Sphenomorphus group spermatozoa (e.g. Ctenotus) and the Egernia group (Tiliqua) differ from the more derived Eugongylus group (C. virgatus, L. delicata and C. pectoralis) in that the acrosome is elongate and apically depressed; the perforatorium is strongly oblique; the midpiece is relatively short, with four dense ring structures in longitudinal succession; mitochondria are columnar; and enlarged peripheral fibres 3 and 8 do not show the gross anterior enlargement seen in Carlia and Lampropholis. Heteronotia binoei (Gekkonidae) sperm have no epinuclear electron‐lucent region; nuclear shoulders are smooth, as in sphenomorph but not Eugongylus group skinks; mitochondria are columnar; unlike skinks, the median surfaces of the mitochondria are indented by triangular, sometimes longitudinally, interconnected dense bodies. In Lialis burtonis (Pygopodidae) sperm, the perforatorium extends virtually to the tip of the fore‐shortened apically domed acrosome; nuclear shoulders are absent; the mitochondria alternate singly or in groups with one or more dense bodies which also form an interrupted collar around the distal centriole. Spermatozoal ultrastructure suggests that a common ancestry of snakes and pygopods deserves consideration.
The Early Phylogeny of Chordates and Echinoderms and the Origin of Chordate Left–Right Asymmetry and Bilateral Symmetry
Authors: Jefferies Richard P. S. , Brown Nigel A. , Daley Paul E. J.
Published: April 2010

Abstract Left–right asymmetry in Dexiothetica (= echinoderms + chordates) results mainly from dexiothetism—an episode in their ancestry when an animal resembling the Recent pterobranch Cephalodiscus lay right‐side‐downwards on the sea floor. Castericystis sprinklei belongs to the dexiothete stem group. The history of the echinoderm stem group is reconstructed. Chordate bilateral symmetry evolved by six successive steps. Tail–head overlap occurred independently in craniates and acraniates. The neural crest would have existed in the latest common ancestor of extant chordates, or even earlier. Gross asymmetries occur in extant chordates in organs derived from the calcichordate head, but not in those derived from the calcichordate tail. The anterior boundary of hox gene expression in vertebrates corresponds to the anterior end of the calcichordate tail. Left–right organ pairing (an important step in the origin of chordate bilateral symmetry) may have involved the interaction of a symmetrizing morphogen, produced from the anterior end of the tail, with a lateral morphogen (Wilhelmi's morphogen), produced in ontogeny at first from the left and later from the right. This mechanism may still act in the metamorphosis of amphioxus and in mirror‐imaging in vertebrate twins. Wilhelmi's morphogen may be related to one or more members of the dorsal cascade of Drosophila.
Use of Sandwich Cultures for the Study of Feeding in the Hexactinellid Sponge Rhabdocalyptus dawsoni (Lambe, 1892)
Authors: Wyeth Russell C. , Leys Sally P. , Mackie George O.
Published: April 2010

Abstract Fragments of sponge tissue were cultured between glass slides and coverslips, permitting direct observation of cytoplasmic movements and tissue organization in vitro. The cut surfaces healed and the cultures lived for periods of several weeks. Cytoplasmic organization appeared similar to that described from study of sectioned material. Uptake of food particles (Escherichia coli, Isochrysis galbana) and latex beads took place primarily in the region of the flagellated chambers. Cytoplasmic streams were seen throughout the preparation and may serve for distribution of nutrients in these syncytial animals. It is proposed that the sandwich cultures are valid models of the intact sponge. Copyright © 1996 The Royal Swedish Academy of Sciences. Published by Elsevier Science Ltd.
Skeletal Ultrastructures in some Cerioporine Cyclostome Bryozoans
Authors: Weedon Michael J. , Taylor Paul D.
Published: April 2010

Abstract The ultrastructure of the calcareous skeleton is described in nine species of Recent cyclostome bryozoans belonging to the suborder Cerioporina. Two species of Heteropora have interior zooecial walls comprising a granular precursory layer followed by a thick layer of transverse fibres and a subordinate foliated fabric with, in mature proximal walls, a semi‐nacreous layer. The remaining seven species have interior walls with no transverse fibres and instead predominantly comprise a distally‐imbricated, regularly foliated fabric overlying a granular precursory layer. Older, proximal surfaces often have abundant screw dislocations, but true semi‐nacre is absent. Basal walls comprise an outer finely granular precursory fabric and planar spherulitic layer, succeeded by the same ultrastructural succession seen in the interior zooecial walls of the respective groups. Exterior walled diaphragms, peristomes and gonozooids similarly comprise an external fabric of planar spherulitic calcite, lined internally by the predominant fabric seen in the interior walls. Ultrastructurally, therefore, cerioporines may be split into two groups with different fabric suites, the first resembling cinctiporids and many tubuliporines in having interior walls with fabrics of transverse fibres, foliated crystallites and semi‐nacre; and the second resembling the rectangulates Lichenopora and Disporella in having interior walls comprising only the foliated fabric. These findings support the close phylogenetic relationship between cerioporines and other cyclostomes but suggest that the cerioporines may constitute either a diphyletic or a paraphyletic group.
Ultrastructure of the Anterior End in Three Ontogenetic Stages of Nectonema munidae (Nematomorpha)
Authors: Schmidt‐Rhaesa Andreas
Published: April 2010

Abstract The structure of the anterior end of three ontogenetically successive stages of Nectonema munidae (Nematomorpha) is investigated by light and transmission electron microscopy. During development, an adult cuticle is formed under a larval cuticle, which is subsequently moulted. Only one moult can be documented for Nectonema. The brain has a main subpharyngeal portion and a weak suprapharyngeal commissure. It is circumpharyngeal only in early developmental stages, the dorsal commissure is reduced in the adult stage. Four giant cells and a cerebral cavity are adult features. Although the morphology of the giant cells is elucidated, their function remains unclear, but a sensory function is probable. A septum marks the posterior border of the anterior end and divides a cerebral cavity from a body cavity. A precursor of the septum is present in the first stage observed, but it lies next to the epidermis and does not separate a cerebral cavity. Cuticular structures in the pre‐pharyngeal region of the early stages are interpreted as remnants of the larval boring organ. They are moulted together with the larval cuticle. The morphology of the pharynx and the anterior part of the intestine is shown.
Anatomy and Phylogenetic Significance of Micropilina arntzi (Mollusca, Monoplacophora, Micropilinidae Fam. Nov.)
Authors: Haszprunar Gerhard , Schaefer Kurt
Published: April 2010

Abstract The anatomy of the neopilinoid limpet Micropilina arntzi (Warén & Hain, 1992, The Veliger 35: 165–176) is described on the basis of graphic reconstructions of semithin serial sections. Hard parts, anatomical features and reproductive biology of the minute species differ considerably from those of all other anatomically known neopilinoid species. Therefore, Micropilinidae fam. nov. is erected for this genus.

Micropilina arntzi may be considered as partly paedomorphic with respect to the seriality of ventilatory (ctenidia), excretory or genital organs, or may represent an archaic condition within the Tryblidiida. Ontogenetic and comparative anatomical data strongly suggest that the serial repetition of the various organ systems should be regarded as one of several autapomorphic features of the Neopilinoidea (Tryblidiida).
Scolex Glands Associated with the Rostella in Three Species of the Dilepididae (Cestoda: Cyclophyllidea)
Authors: Stoitsova Stoyanka R. , Georgiev Boyko B. , Dacheva Raina B. , Vinarova Maria I.
Published: April 2010

The microanatomy, fine structure and cytochemistry of scolex glands of Vitta riparia, Angularella beemaand Trichocephaloidis megalocephalaare examined by light and electron microscopy. Cytochemical tests include PAS, mercury bromphenol blue and performic acid‐alcian blue for light microscopy and periodic acid‐thiocarbohydrazide‐OsO4 for electron microscopy. The scolex glands are organized in two spatially isolated syncytia, one located in the rostellum, the other in the rostellar sac. The cytoplasm of the gland syncytia is characterized by a high affinity for haematoxylin. Cytochemical tests indicate the presence of moderate amounts of glycoprotein in the glands. A specialized type of secretion—dark oval or ovoid bodies with diameter 0.3–0.5 μm are observed by EM in both the rostellum glands and the rostellar‐sac glands of V. ripariaand T. megalocephala, and in the rostellar‐sac gland of A. beema. The rostellum gland of A. beemaproduces larger dark oval bodies measuring up to 0.9 μm. Lipid droplets are also observed in the glandular cytoplasm. Some tegumental cytons containing discoid bodies are found between the glandular perikarya. The glandular products and the lipid droplets are secreted via the rostellar tegument. © 1997 Published by Elsevier Science Ltd on behalf of The Royal Swedish Academy of Sciences.
Sperm Ultrastructure of Tarsius bancanus(Tarsiidae, Primates): Implications for Primate Phylogeny and the Use of Sperm in Systematics
Authors: Robson Simon K. , Rouse Greg W. , Pettigrew John D.
Published: April 2010

The ultrastructure of the epididymal sperm of Tarsius bancanusis described. The sperm possess the typical eutherian pattern of a dorsoventrally flattened, ovate sperm head, comprising a nucleus capped by a symmetrical acrosome, and a distinct midpiece and principal piece containing a 9 + 9 + 2 arrangement of outer coarse fibres and microtubules. However, unique features are also present. The overall head length (9 μm) equals the greatest for any primate yet examined, and the subacrosomal space (“perforatorium” or “pseudoperforatorium”) tilted at 30° to the sagittal axis of the sperm, is described for the first time for mammals. The acrosome extends only a short distance beyond the length of the nucleus of the mature sperm, and a significant reduction in the acrosome to nuclei ratio appears to occur during the final stages of sperm maturation. In contrast to earlier predictions based on the spermatid of Tarsius syrhicta, the mature spermatozoa of Tarsiusshows greatest morphological similarity with the sperm of the Anthropoidea, which have a short symmetrical acrosome, than with the Strepsirhini, which have a relatively long acrosome that can be either symmetrical (Lemuriformes) or asymetrical (Lorisiformes). Four proposed phylogenies of the Primates are assessed using comparative sperm ultrastructure. Placing the Tarsiidae as a sister group to the Lorisidae appears the least likely. The sperm data are consistent with the Tarsiidae being a sister group to the Anthropoidea, to the Strepsirhini, or even to the extant primate groups as a whole. Use of sperm morphology to provide characters in phylogenetic systematics of the primates is discussed, and the principle of “total evidence” is preferred to the common practice of “hanging” sperm on phylogenetic hypotheses based on other evidence. © 1997 The Royal Swedish Academy of Sciences. Published by Elsevier Science Ltd.
Sensory Organs on the Antennae of Micropterix calthella L. (Lepidoptera, Micropterigidae)
Authors: Faucheux Michel J.
Published: April 2010

Antennal sensilla of Micropterix calthella were studied with the scanning electron microscope to determine their morphological types, relative abundance, distribution, location and possible functions. Of the 12 types occurring in both male and female moths, seven are found in most higher Lepidoptera: sensilla trichodea, multiporous s. basiconica, s. coeloconica, s. styloconica, s. chaetica, s. campaniformia and Böhm's bristles. Two types (uniporous s. basiconica and cupuliform organs) are found only in a few families. Three structures are peculiar to Micropterix: ascoïd sensilla, multiporous s. placodea and circular organs. All types of sensilla have characteristic distribution and location pattern similar in both sexes.
Characteristics of Spermatozoa from Five Gall‐Midge Species (Diptera, Cecidomyiidae)
Authors: Dallai Romano , Lupetti Pietro , Frati Francesco , Mamaev Boris M. , Afzelius Björn A.
Published: April 2010

The gall‐midge family Cecidomyiidae is one of the largest within the animal kingdom. Its characteristics include, among others, a chromosome elimination during spermiogenesis and a bewildering diversity in sperm ultrastructure. The sperm tail, in particular, is unusual in that it deviates from the conventional 9+2 pattern of microtubules. We describe here the spermatozoa of five gall‐midge species, all belonging to the same supertribe Cecidomyiidi. In Bremia more than 100 microtubular doublets form a tight spiral around a central mitochondrion. In an undetermined binomen many doublets form a spiral around the mitochondria in the distal end of the sperm tail, but a single row along a peripheral cistern in the main part of the tail. In Coquillettomyia caricis a peripheral row of doublets resides in the proximal part and tightly packed doublets distally. In Arthrocnodax sp. the many doublets also form a peripheral single or double row around a central mitochondrion. In Massalongia bachmaieri there are more than 500 doublets which form several rows around the nucleus and tightly packed doublets distally. The nuclear membrane forms bundles of extensive outpocketings. There is no acrosome. The nucleus consists of both condensed and dispersed material. Only outer dynein arms are present in all this species and the spermatozoa are motile. Cecidomyiidi species that have been examined for sperm structure fall into two groups: those where the mitochondria are confined to the centre of the tail and those in which the mitochondria lie in the head region and have a peripheral location. Most species belong to the first group, while Massalongia belongs to the second one.
Ultrastructure of the Tegumental Basement Membrane of Fasciola hepatica(Trematoda)
Authors: Stoitsova Stoyanka , Gorchilova Lyubomila
Published: April 2010

The fine–structural characteristics of the basement membrane of the tegument of F. hepaticawere examined following extraction fixations and tannic acid infiltration. The basement membrane was shown to consist of three layers: lamina lucida, lamina densa, and lamina reticularis. The lamina densa appeared amorphous and homogeneous with tannic acid impregnation. The lamina reticularis appeared as a dense network of 10–12 nm fibrils. Anchoring fibrils cross this layer and form loops. Along their length they contact hemidesmosomes of muscles, thus connecting muscle to muscle and to tegument. The tegument/basement membrane contact is enhanced by extensions of the lamina densa into infoldings of the tegumental basal membrane. Where tegumental spines reach the basement membrane, the contact is reinforced by hemidesmosomes that connect to anchoring fibrils reaching toward the underlying muscles. The basement membrane thus seems to be a complex structure integrating the distal tegumental layer with underlying tissues and transducing muscle contractions to the tegument and its spines.
Form and Function of the Primary Spines of Two Bathyal Echinothuriid Sea Urchins
Authors: Emson R. H. , Young C. M.
Published: April 2010

The appearance, in situ activity and structure of the primary spines of the two deep sea echinothuriid sea urchins Phormosoma placenta and Araeosoma belli are described with particular reference to the unusual, fleshy, aboral spines. Oral primary spines of both species are clearly but differently adapted for movement over soft substrata. The aboral spines of both species bear fleshy extensions which are composed of gelatinous material in both species and are not poison sacs.

Field experiments showed that the fleshy parts of the aboral spines of P. placenta are palatable to shallow‐water fish. However, the aboral spines are shown to have stored within the hollow ossicle of the spine secretory material likely to be irritant in function. The structure of the tip of the spine ossicle of both species suggests that they may act like hypodermic needles. We conclude that the aboral spines of both species are probably defensive in function but remain equivocal over the exact role of the massive fleshy extensions found in P. placenta. Other possible non‐defensive functions are briefly discussed.
Skeletal Ultrastructure in Some Articulate Cyclostome Bryozoans
Authors: Weedon Michael J. , Taylor Paul D.
Published: April 2010

The ultrastructure of the calcareous skeleton is described in 11 species of articulate cyclostome bryozoans with elastic joints. Ten species have interior walls comprising semi‐nacreous and pseudofoliated fabrics without a precursory granular layer. Exterior walls consist of outer, finely granular and planar spherulitic layers, succeeded by semi‐nacreous and pseudofoliated fabrics like those of interior walls. Outer fabrics are calcified as longitudinal strips, each corresponding to a planar sphcrulitic unit. Articulation surfaces comprise ring diaphragms of very fine granular fabric with concentric laminations. The semi‐nacre of walls adjacent to ring diaphragms contains minute holes. Crisulipora occidentalis is unique in having interior walls of transverse fibres succeeded by pseudofoliated fabric, articulation surfaces festooned with deep pits but lacking well‐differentiated ring diaphragms, and pseudopores containing sieve‐like closure plates. The ultrastructure of most articulates resembles tubuliporine cyclostomes with dominantly semi‐nacreous walls, although the lack of precursory granular fabric in the interior walls and the presence of subcircular tablets of semi‐nacre (without six‐fold sectoring) may be peculiar to articulates. In contrast, Crisulipora is more similar to other tubuliporines with transverse fibres. evidence which, together with other skeletal characters, suggests that Crisulipora evolved jointing independently of the rest of the articulate cyclostomes.
Skeletal Ultrastructure of the Early Astogenetic Stages of Some Cyclostome Bryozoans
Authors: Weedon Michael J.
Published: April 2010

The calcific protoecia of cyclostome bryozoans have remarkably uniform skeletal ultrastructure in three suborders (Tubuliporina, Cancellata and Rectangulata). The basal wall or floor has a fine outer granular layer succeeded by planar spherulitic fabric, internally lined by irregular semi‐nacre. The roof of the disc comprises an outer granular layer with an inner lining of semi‐nacre continuous with that of the floor; planar spherulitic fabric is absent. Growth of the floor of the disc is initiated around the circular outer rim and continues centripetally to the centre; the inner lining has no prevailing growth direction. The gently domed roof also initiates around the outer rim, and grows in strips, which grow toward the centre, then distally toward the distal tube of the ancestrula which has a fully adult ultrastructure. Protoecia] ultrastructure is independent of adult ultrastructure. The uniformity of skeletal ultrastructure in cyclostomes corresponds with the close similarity of larvae and post‐settlement metamorphosis in the order. The fabric suite of the protoecium resembles the skeletal ultrastructure of Palaeozoic stenolaemates. The primitive fabric condition is retained by some tubuliporines and cancellates. Complex multilayered fabric suites may have evolved in the Mesozoic by addition of new fabric types.
The Oxygen Receptor of the Teleost Gill?
Authors: Sundin Lena , Holmgren Susanne , Nilsson Stefan
Published: April 2010

The gills of the Atlantic cod, Gadus morhua, were studied using immunohistochemical techniques. Primary antibodies directed against serotonin (5‐hydroxytryptamine, 5‐HT) and acetylated α‐tubulin were used to visualise cells containing serotonin and nerve fibres, respectively. Three morphologically different 5‐HT immunoreactive cell types were distinguished: (I) Neuroepithelial cells (NECs), which were abundant along the distal half of the efferent filamental arteries (EFAs), and particularly formed distinct clusters at the individual filamental tips, (II) bipolar neurones running next to the EFAs and (III) multipolar neurones innervating the proximal parts of the EFA. In addition, the study revealed a well‐developed system of nerve fibres, some of which form plexuses in association with the NECs. A relatively rich innervation of the proximal part of the EFAs, in conjunction with the EFA sphincters was also observed. Delicate varicose terminals surround the bases of the efferent lamellar arterioles. The localisation of distinct clusters of NECs at the individual filamental tips and the close connection with nerve terminals suggests a function as external branchial oxygen receptors.
The GAIF‐Positive Population of Neurons in the Evolution of the Temnocephalida
Authors: Joffe Boris. I. , Cannon Lester R. G.
Published: April 2010

The nervous system of three species of the Temnocephalida has been studied using the GAIF method (which in small flatworms mostly reveals sensory catecholaminergic neurons). These species represent the evolution from the primitive “turbellarian‐like” temnocephalids to the most specialised ones with tentacles and a sucker. The numbers and positions of GAIF‐positive neurons are invariant within each species and do not change from hatching to full maturity. A characteristic unpaired neuron contributing to the innervation of the anterior margin of the body is present in all species: such a cell has previously been found only in marine Thalassovortex tyrrhenicus (Dalyellidae) which confirms close relationships between these taxa. Our series of species shows (i) a reduction in number of GAIF‐positive perikarya associated with the lateral cords and reduction of GAIF‐positive innervation on the ventral side of the body, which is probably related to the loss of ciliary locomotion (the shift to passive hunting and looping locomotion) and (ii) reinforcement of the GAIF‐positive innervation of the anterior end of the body which begins to play an important role in capturing the prey. The retention of the medial unpaired neuron and nearly identical sets of GAIF‐positive neurons in Diceratocephala boschmai and Craspedella pedum (rather different in morphology) give the first indication (in the Plathelminthes) of persistence of homologous neurons through significant evolutionary transformations of the organs they innervate.
Ultrastructural Analysis of the Sensilla of Austroperipatus aequabilis Reid, 1996 (Onychophora, Peripatopsidae)
Authors: Bittner Kerstin , Ruhberg Hilke , Storch Volker
Published: April 2010

The head of Austroperipatus aequabilis bears five types of sensilla. which were examined by electron microscopy. They differ from each other in position, shape of outer sensory elements and cuticular socket structures. Thus, we distinguish sensilla with sensory hairs, sensilla with sensory bulbs, cone‐shaped sensilla. sensilla with sensory bristles, and sensilla of the lips. They are composed of up to 15 cells, which can he separated into four cell types. The most frequent cell type is the bipolar receptor cell that occurs in all sensilla. The apical surface of this primary receptor cell is characterized by one or two partly branched cilia with a basal 9 × 2 + 0 pattern of microtubules. A modified bipolar receptor cell was found in all sensilla bearing a sensory peg except for the sensilla equipped with sensory bristles. The apical dendrite extends to a long pale process which exclusively contains mitochondria and single microtubules. In all sensilla examined in this study at least one supporting cell occurs which is characterized by parallel microvilli. An additional function of this cell type as a part of the stimulus‐conducting system is possible. In the sensillum with a sensory bulb two kinds of supporting cells occur. A unique cell type with an upside down position has regularly been found in all sensilla bearing a sensory peg. Apart from the sensilla they also occur within the labial epidermis. Since most sensilla contain several different receptor cells, they can be considered as complex sense organs. © 1998 The Royal Swedish Academy of Sciences. Published by Elsevier Science Ltd. All rights reserved
Immunohistochemical Study of the Origin of the Subepicardial Mesenchyme in the Dogfish (Scyliorhinus canicula)
Authors: Macías D. , Pérez‐Pomares J. M. , García‐Garrido L. , Muñoz‐Chápuli R.
Published: April 2010

A mesenchyme appears at the subepicardium of the vertebrate embryo closely following the epicardial ensheathing of the heart. We have suggested earlier that a localized epithelial‐mesenchymal transition (= transdifferentialion) of the epicardial mesothelium might explain the origin of the subepicardial mesenchymal cells (SEMC) in a primitive vertebrate, the dogfish Scyliorhinus canicula. We have tested our hypothesis through the immunolocalization, in the embryonic dogfish heart, of three proteins involved in the epithelial—mesenchymal transitions. Fibronectin immunoreactivity (FN‐IR) was present between epicardium and myocardium from the earliest stages of the epicardial development. However, in embryos ranging between 20 and 35 mm TL, FN‐IR disappeared from the basal surface of the epicardial cells at the atrioventricular and conoventricular grooves and increased in association with the SEMC. Proliferating‐cell nuclear antigen immunoreactivity was intense in most epicardial cells and SEMC in these areas and developmental stages, but it declined in later embryos. The JB3 antigen, a fibrillin‐related protein, was delected in the cytoplasm and basal surface of the epicardial cells, as well as on the SEMC surface. These immunohistochemical patterns were remarkably similar at the subepicardium and at the endocardial cushions, which are populated by mesenchymal cells derived from the transdifferentiation of the endocardium. © 1998 The Royal Swedish Academy of Sciences. Published by Elsevier Science Ltd. All rights reserved
RESEARCH SECTION: Classroom interaction in regular and special education middle primary classrooms in the United Arab Emirates
Authors: Dukmak Samir
Published: April 2010

Samir Dukmak is an assistant professor in the Department of Special Education in the Faculty of Education at the United Arab Emirates University. The research reported in this article investigated the frequency, types of and reasons for student‐initiated interactions in both regular and special education classrooms in the United Arab Emirates (UAE). These interactions were studied in relation to various variables, including levels of students' academic achievement, their gender, special educational needs and disability. Teacher‐initiated interactions were also examined in the study. Eighteen boys and girls from two regular and two special education classrooms were observed. Various types of interaction were identified among students and the results reveal that boys in all groups initiated more interactions than girls, and that high‐achieving boys and girls initiated more interactions than their low‐achieving counterparts. The findings also reveal that teachers interacted differently with boys versus girls. The reasons prompting students to initiate classroom interaction are highlighted in this research.
FOCUS ON PRACTICE: Living with children diagnosed with autistic spectrum disorder: parental and professional views
Authors: Dillenburger Karola , Keenan Mickey , Doherty Alvin , Byrne Tony , Gallagher Stephen
Published: April 2010

The number of children diagnosed with an autistic spectrum disorder (ASD) is rising and is now thought to be as high as 1:100. While the debate about best treatment continues, the effects of having a child diagnosed with ASD on family life remain relatively unexplored. This article, by Karola Dillenburger of Queens University Belfast, Mickey Keenan of the University of Ulster, Alvin Doherty from the Health Service Executive Western Region, Tony Byrne of Parents' Education as Autism Therapists (PEAT) and Stephen Gallagher of the University of Ulster, sets out to adjust that balance. Drawing upon data from a comprehensive study of parental needs, these authors argue that parental and professional views do not always concur; that families make extraordinary sacrifices; that siblings are affected; and that parents are under tremendous stress. Parents argue that educational and social service supports are not efficient and that they are forced to rely largely on support from within the family or from friends. In particular, some important differences between parental and professional perceptions became apparent in relation to interventions based on Applied Behaviour Analysis (ABA). The authors of this article propose that these differences need to be taken seriously by teachers and other professionals as well as by policy‐makers.
Care management in practice: on the use of talk and text in gerontological social work
Authors: Cedersund Elisabet , Olaison Anna
Published: April 2010

Cedersund E, Olaison A. Care management in practice: on the use of talk and text in gerontological social work

Int J Soc Welfare 2010: 19: 339–347 © 2010 The Author(s), Journal compilation © 2010 Blackwell Publishing Ltd and International Journal of Social Welfare.

This is a study of encounters between social workers and citizens in one type of welfare organisation, the municipal elder care system. The article sheds light on how older people's claims are dealt with in the processing of home care applications. Twenty encounters between social workers and older people were studied using discourse analysis. The findings reveal that discursive practices are part of the routine when the applications are processed. The application handling follows an agenda‐bound pattern that is visible in the encounters. In these standardised procedures, oral discourse is embedded in routines that also include the use of texts. However, within this institutional order, there is also an important element of negotiation between the parties. It is therefore claimed that the encounters include a negotiated order that does not exist on its own, but is achieved in the ongoing interaction.
Compromised vascular endothelial cell SKCa activity: a fundamental aspect of hypertension?
Authors: Garland Christopher J
Published: April 2010

Smooth muscle hyperpolarization originating in the endothelium and commonly referred to as the EDHF (endothelium‐derived hyperpolarizing factor) response provides a very significant drive to vasodilatation particularly in small resistance arteries. Together with other endothelium‐dependent dilator pathways ‘EDHF’ hyperpolarization is compromised by cardiovascular disease, including hypertension. However, although attenuated vascular hyperpolarization has been described in animal models of hypertension, the underlying mechanisms are not fully understood. In the current issue of the British Journal of Pharmacology, Weston et al. combine classic pharmacological approaches with electrophysiological and molecular techniques to suggest that attenuated endothelium‐dependent hyperpolarization (and as a consequence vasodilatation) reflects major disruption of pathways associated with the activation of endothelial small conductance Ca2+‐activated K‐channels (SKCa) in mesenteric arteries from spontaneously hypertensive rats. In addition to reductions in SKCa and KIR proteins, changes in caveolin‐1 isomers were also detected, possibly indicating channel realignment within plasmalemmal structures.

This article is a commentary on Weston et al., pp. 836–843 of this issue. To view this paper visit http://dx.doi.org/10.1111/j.1476‐5381.2010.00657.x
Video versus traditional informed consent for neonatal circumcision
Authors: Chantry Caroline J , Byrd Robert S , Sage Allyson C , Calvert Emma E
Published: April 2010

Abstract Aim:  To determine if videotapes about newborn circumcision would be superior to traditional physician ‘informed consent’ discussion for maternal knowledge, satisfaction and perception of provider bias.

Design/methods:  A convenience sample of mothers interested in or undecided about circumcision was randomized to watch a video on: (i) circumcision risks/benefits (‘Video‐Plus’ n = 168); or (ii) unrelated material followed by traditional physician risk/benefit discussion (‘Standard‐MD’ n = 136). Questionnaires were administered during hospitalization and subsequent telephone interviews. Statistical differences were analysed by chi‐square and Wilcoxon signed rank test.

Results:  Most mothers (82%) decided about circumcision prenatally. Fewer mothers perceived bias from the video vs. physicians [1.1% vs. 6.8%, p = 0.04]. Composite knowledge (correct of 10 answers) [ (SD) 6.5 (2.1) vs. 6.4 (2.1), p = 0.78] or satisfaction [5‐point Likert scale, 3.98 (1.50) vs. 3.75 (1.58), p = 0.16] did not differ by group, although more highly educated mothers preferred the video [satisfaction 4.08 (1.01) vs. 2.63 (0.99), p = 0.04]. Significant knowledge gaps existed in both groups.

Conclusion:  In this setting, no difference in maternal knowledge was found between ‘Video‐Plus’ and traditional informed consent although more highly educated mothers preferred the video. Better ways to achieve understanding of risks and benefits for this elective procedure should be sought.
Therapeutic management of neonatal chylous ascites: report of a case and review of the literature
Authors: Karagol Belma Saygili , Zenciroglu Aysegul , Gokce Selim , Kundak Ahmet Afsin , Ipek Mehmet Sah
Published: April 2010

Congenital chylous ascites is a rare condition seen in the neonatal period and the data on pathogenesis and treatment modalities are limited. In this article, we report a case of neonate with chylous ascites and review the therapeutic management procedures on chylous ascites in childhood. We present our experience in the diagnosis and treatment of this condition.

Conclusion:  Medium‐chain triglycerides (MCT)‐based diet can be tried as a first option in chylous ascites treatment. In resistant or unresponsive cases, somatostatin along with TPN can have use in closing the lymphatic leakage or relieving the symptoms effectively and rapidly. Conventional regimens including enteral feeding with MCT‐based formula can then be re‐administered as a maintenance treatment after reduction of lymph flow with the use of total parenteral nutrition (TPN) and somatostatin infusion combination. Patient‐specific approach should be attempted for chylous ascites caused by various disorders and started as soon as possible.
GIP and GLP‐1, the two incretin hormones: Similarities and differences
Authors: Seino Yutaka , Fukushima Mitsuo , Yabe Daisuke
Published: April 2010

Gastric inhibitory polypeptide (GIP) and glucagon‐like peptide‐1 (GLP‐1) are the two primary incretin hormones secreted from the intestine on ingestion of glucose or nutrients to stimulate insulin secretion from pancreatic β cells. GIP and GLP‐1 exert their effects by binding to their specific receptors, the GIP receptor (GIPR) and the GLP‐1 receptor (GLP‐1R), which belong to the G‐protein coupled receptor family. Receptor binding activates and increases the level of intracellular cyclic adenosine monophosphate in pancreatic β cells, thereby stimulating insulin secretion glucose‐dependently. In addition to their insulinotropic effects, GIP and GLP‐1 play critical roles in various biological processes in different tissues and organs that express GIPR and GLP‐1R, including the pancreas, fat, bone and the brain. Within the pancreas, GIP and GLP‐1 together promote β cell proliferation and inhibit apoptosis, thereby expanding pancreatic β cell mass, while GIP enhances postprandial glucagon response and GLP‐1 suppresses it. In adipose tissues, GIP but not GLP‐1 facilitates fat deposition. In bone, GIP promotes bone formation while GLP‐1 inhibits bone absorption. In the brain, both GIP and GLP‐1 are thought to be involved in memory formation as well as the control of appetite. In addition to these differences, secretion of GIP and GLP‐1 and their insulinotropic effects on β cells have been shown to differ in patients with type 2 diabetes compared to healthy subjects. We summarize here the similarities and differences of these two incretin hormones in secretion and metabolism, their insulinotropic action on pancreatic β cells, and their non‐insulinotropic effects, and discuss their potential in treatment of type 2 diabetes. (J Diabetes Invest, doi: 10.1111/j.2040‐1124.2010.00022.x, 2010)
An extension of Buchberger’s criteria for Gröbner basis decision
Authors: Perry John
Published: April 2010

Two fundamental questions in the theory of Gröbner bases are decision (‘Is a basis G of a polynomial ideal a Gröbner basis?’) and transformation (‘If it is not, how do we transform it into a Gröbner basis?’) This paper considers the first question. It is well known that G is a Gröbner basis if and only if a certain set of polynomials (the S-polynomials) satisfy a certain property. In general there are m(m−1)/2 of these, where m is the number of polynomials in G, but criteria due to Buchberger and others often allow one to consider a smaller number. This paper presents two original results. The first is a new characterization theorem for Gröbner bases that makes use of a new criterion that extends Buchberger’s criteria. The second is the identification of a class of polynomial systems G for which the new criterion has dramatic impact, reducing the worst-case scenario from m(m−1)/2 S-polynomials to m−1.
Mobility of Single-Loop Kinematic Mechanisms Under Differential Displacement
Authors: Milenkovic Paul
Published: April 2010

Linear analysis of motion screws is a means for determining the mobility of a mechanism composed of the parallel combination of serial kinematic chains. Such a mechanism may have one or more degrees of freedom that vanish after a differential displacement from a reference posture. The Lie product, also called the Lie bracket, is known to give the derivative of a motion screw with respect to the displacement along an upstream screw in a serial chain. Serial chains having motion screws that are closed under the Lie product are known to retain their mobility after differential displacement. For a single-loop mechanism, which is composed of a pair of chains that are not closed under the Lie product, mobility is retained when the Lie closures of those chains are within the span of the union of motion screws of the two chains, a new result determined by applying the Baker–Campbell–Hausdorff expansion to the motion screws of the serial chain. When the Lie products have at most one dimension outside the union span, a second-order expression of mobility reduces to a quadratic form, allowing the numerical characterization of constraint singularities under that condition.
A Multiscale Design Methodology for Hierarchical Systems With Random Field Uncertainty
Authors: Chen Wei , Yin Xiaolei , Lee Sanghoon , Liu Wing Kam
Published: April 2010

A multiscale design methodology is proposed for hierarchical material and product systems with random field uncertainty that propagates across multiple length scales. Using the generalized hierarchical multiscale decomposition pattern in multiscale modeling, a set of computational techniques is developed to manage the system complexity. Design of experiments and metamodeling strategies are proposed to manage the complexity of propagating random field uncertainty through three generalized levels of transformation: the material microstructure random field, the material property random field, and the probabilistic product performance. Multilevel optimization techniques are employed to find optimal design solutions at individual scales. A hierarchical multiscale design problem that involves a two-scale (submicro- and microscales) material design and a macroscale product (bracket) design is used to demonstrate the applicability and benefits of the proposed methodology.
Using Parameterized Pareto Sets to Model Design Concepts
Authors: Malak Richard J. , Paredis Christiaan J. J.
Published: April 2010

The decisions designers make during conceptual design can have a large impact on the success of a project. Conceptual design decisions can be challenging because the imprecise nature of design concepts make them difficult to model. Prior literature exists on using Pareto sets to model design concepts abstractly in the space of decision attributes. However, this approach has limitations when the concept under consideration is a component of a larger system. The need to relate component-level decision attributes to system-level decision objectives can lead to a violation of the assumptions underlying classical Pareto dominance. The main contribution of this article is a new dominance criterion, called parameterized Pareto dominance, which is applicable in such situations. It is a generalization of the classical dominance rule and is found to be sound from a decision-theoretic perspective. A secondary contribution is the articulation of a generalized methodology for constructing concept models based on classical or parameterized Pareto sets using either observational or model-generated data. The modeling procedure, including the new dominance criterion, is demonstrated on observational data about hydraulic cylinders. The question of whether a parameterized Pareto set can be an adequate representation of a component-level design concept is evaluated on a gearbox conceptual design problem for which the component-level decision is subordinate to system-level vehicle design problem.
Metrics for Evaluating the Barrier and Time to Reverse Engineer a Product
Authors: Harston Stephen P. , Mattson Christopher A.
Published: April 2010

Reverse engineering, defined as extracting information about a product from the product itself, is a common industry practice for gaining insight into innovative products. Both the original designer and those reverse engineering the original design can benefit from estimating the time and barrier to reverse engineer a product. This paper presents a set of metrics and parameters that can be used to calculate the barrier to reverse engineer any product, as well as the time required to do so. To the original designer, these numerical representations of the barrier and time can be used to strategically identify and improve product characteristics so as to increase the difficulty and time to reverse engineer them. As the metrics and parameters developed in this paper are quantitative in nature, they can also be used in conjunction with numerical optimization techniques, thereby enabling products to be developed with a maximum reverse engineering barrier and time—at a minimum development cost. On the other hand, these quantitative measures enable competitors who reverse engineer original designs to focus their efforts on products that will result in the greatest return on investment.
Integrated Structural and Controller Optimization in Dynamic Mechatronic Systems
Authors: Albers Albert , Ottnad Jens
Published: April 2010

In order to take into account the interaction between the part, dynamic system, control system, and changing mechanical behavior with all its consequences for the optimization process, a simulation of the complete mechatronic system is integrated into the optimization process within the research work presented in this paper. A hybrid multibody system (MBS) simulation, that is a MBS containing flexible bodies, in conjunction with a cosimulation of the control system represented by tools of the computer aided control engineering, is integrated into the optimization process. By an inner optimization loop the controller parameters are adopted new in each of the iterations of the topology optimization in order to provide realistic load cases. The benefits will be illustrated by an example in conjunction with the humanoid robot ARMAR III of the Collaborative Research Centre 588 “Humanoid Robots-Learning and Cooperating Multimodal Robots” in Karlsruhe Germany. It will be shown how the new approach for the optimization of parts “within” their surrounding mechatronic system allows an efficient optimization of such structures.
What's Lost When Languages Are
When Languages Die
The Extinction of the World's Languages and the Erosion of Human Knowledge

by K. David Harrison

Oxford University Press, Oxford, 2008. 304 pp. Paper, $17.95, £11.99. ISBN 9780195372069.
Authors: Pires Acrisio
Published: April 2010

Harrison explores causes and consequences of the loss of human languages.
Literacy and Science: Each in the Service of the Other
Authors: Pearson P. David , Moje Elizabeth , Greenleaf Cynthia
Published: April 2010

We use conceptual and empirical lenses to examine synergies between inquiry science and literacy teaching and learning of K-12 (kindergarten through high school) curriculum. We address two questions: (i) how can reading and writing be used as tools to support inquiry-based science, and (ii) how do reading and writing benefit when embedded in an inquiry-based science setting? After elaborating the theoretical and empirical support for integrated approaches, we discuss how to support their implementation in today’s complicated curricular landscape.
Arguing to Learn in Science: The Role of Collaborative, Critical Discourse
Authors: Osborne Jonathan
Published: April 2010

Argument and debate are common in science, yet they are virtually absent from science education. Recent research shows, however, that opportunities for students to engage in collaborative discourse and argumentation offer a means of enhancing student conceptual understanding and students’ skills and capabilities with scientific reasoning. As one of the hallmarks of the scientist is critical, rational skepticism, the lack of opportunities to develop the ability to reason and argue scientifically would appear to be a significant weakness in contemporary educational practice. In short, knowing what is wrong matters as much as knowing what is right. This paper presents a summary of the main features of this body of research and discusses its implications for the teaching and learning of science.