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Right Angles (right + angle)
Selected AbstractsTracheal tube fixation: the effect on depth of insertion of midline fixation compared to the angle of the mouth,ANAESTHESIA, Issue 4 2009K. Sharma Summary Following successful placement of a tracheal tube (TT), it is frequently moved from the midline to the angle of the mouth. This study investigates the tracheal tube tip position in the two fixation positions in 200 adult patients. Following tracheal intubation, a fibreoptic bronchoscope (FOB) was introduced through a swivel connector and the distances from the swivel connector to the lips, carina, tip of TT and the crico-tracheal membrane were measured with the TT in the midline and at the right angle of the mouth. The mean (SD) TT tip to carinal distance decreased from 3.60 (1.50) cm to 2.28 (1.55) cm in female patients, and 5.04 (1.43) cm to 3.69 (1.65) cm in male patients on moving the tracheal tube to the angle of the mouth. We conclude that there is a significant movement of the tracheal tube towards the carina on moving the TT from midline to angle of mouth and the depth of insertion of the tube should be adjusted accordingly. [source] Modification of Supramolecular Binding Motifs Induced By Substrate Registry: Formation of Self-Assembled Macrocycles and Chain-Like PatternsCHEMISTRY - A EUROPEAN JOURNAL, Issue 42 2009Leslie-Anne Fendt Abstract The self-assembly properties of two ZnII porphyrin isomers on Cu(111) are studied at different coverage by means of scanning tunneling microscopy (STM). Both isomers are substituted in their meso -positions by two voluminous 3,5-di(tert -butyl)phenyl and two rod-like 4,-cyanobiphenyl groups, respectively. In the trans -isomer, the two 4,-cyanobiphenyl groups are opposite to each other, whereas they are located at right angle in the cis -isomer. For coverage up to one monolayer, the cis- substituted porphyrins self-assemble to form oligomeric macrocycles held together by antiparallel CN,,,CN dipolar interactions and CN,,,H-C(sp2) hydrogen bonding. Cyclic trimers and tetramers occur most frequently but everything from cyclic dimers to hexamers can be observed. Upon annealing of the samples at temperatures >150,°C, dimeric macrocyclic structures are observed, in which the two porphyrins are bridged by Cu atoms, originating from the surface, under formation of two CN,,,Cu,,,NC coordination bonds. The trans -isomer builds up linear chains on Cu(111) at low coverage, whereas for higher coverage the molecules assemble in a periodic, densely packed structure. Both cis - and trans -bis(4,-cyanobiphenyl)-substituted ZnII porphyrins behave very differently on Cu(111) compared to similar porphyrins in literature on less reactive surfaces such as Au(111) and Ag(111). On the latter surfaces, there is no signal visible between molecular orientation and the crystal directions of the substrate, whereas on Cu(111), very strong adsorbate,substrate interactions have a dominating influence on all observed structures. This strong porphyrin,substrate interaction enables a much broader variety of structures, including also less favorable intermolecular bonding motifs and geometries. [source] Vivosorb®, Bio-Gide®, and Gore-Tex® as barrier membranes in rat mandibular defects: an evaluation by microradiography and micro-CTCLINICAL ORAL IMPLANTS RESEARCH, Issue 5 2008Pepijn F. M. Gielkens Abstract Objectives: The objectives of this study were to determine whether a new degradable synthetic barrier membrane (Vivosorb®) composed of poly(dl -lactide-,-caprolactone) (PDLLCL) can be useful in implant dentistry and to compare it with collagen and expanded polytetrafluoroethylene (ePTFE) membranes. Material and methods: In 192 male Sprague,Dawley rats, a standardized 5 mm circular defect was created through the right angle of the mandible. New bone formation was evaluated by post-mortem microradiography and micro-CT (,CT) imaging. Four groups (control, PDLLCL, collagen, ePTFE) were evaluated at three time intervals (2, 4, and 12 weeks). In the membrane groups the defects were covered; in the control group the defects were left uncovered. Data were analysed using a multiple regression model. Results: New bone formation could be detected by post-mortem microradiography in 130 samples and by ,CT imaging in 112 samples. Bone formation was progressive in 12 weeks, when the mandibular defect was covered with a membrane. Overall, more bone formation was observed underneath the collagen and ePTFE membranes than the PDLLCL membranes. Conclusions: In contrast to uncovered mandibular defects, substantial bone healing was observed in defects covered with a PDLLCL membrane. However, bone formation in PDLLCL-covered defects tended to be less than in the defects covered with collagen or ePTFE. The high variation in the PDLLCL samples at 12 weeks may be caused by the moderate adherence of this membrane to bone compared with collagen. These results indicate that further study is needed to optimize the properties of PDLLCL membranes. [source] A survey of interfacial forces used during filing of root canalsDENTAL TRAUMATOLOGY, Issue 3 2000J. D. Regan Abstract , The pattern of dentine removal during endodontic instrumentation is influenced by many factors including the interfacial forces applied by the operator. The aim of this study was to investigate the influence of operators and different sizes and types of instruments on the magnitude of these interfacial forces. Single-rooted teeth were mounted on a cantilevered aluminium beam to which two pairs of single element strain gauges were joined in a half-bridge configuration and mounted at right angles to each other. The strain gauges were connected to an analogue-to-digital converter fitted in a micro-computer via conditioning amplifiers. This enabled strains to be recorded over a period of time. Twenty operators instrumented root canals using a series of hand instruments for 1 min each. The mean interfacial forces used by operators demonstrated a wide variation ranging from 9.06 g to 149.42 g (range of forces from 0,331 g) but there was a consistency in the relative magnitude for each operator. The 20 operators could be divided into 13 groups which were significantly different (,=0.05) from each other. There were significant differences (,=0.05) between the forces used for each of the K-Flex files (15, 25, 35, 45, and 70), the force increasing with the file size. There was also a significant difference (,=0.05) in the forces used between the Flexofile (#25) and the #25 K-Flex and Hedström files. However, there was no significant difference between the K-Flex and Hedström files. [source] Ease of reading of mandatory information on Canadian food product labelsINTERNATIONAL JOURNAL OF CONSUMER STUDIES, Issue 4 2009Mary Alton Mackey Abstract Food product labels present individual product information, safety, nutrition, electronic inventory, container and environmental information, in various formats, languages and images. Some information is mandatory; much is promotional. The food label is an essential tool for regulators of safe food handling, nutrition policy and fair competition. Mandatory information on food labels in Canada is required to be presented in both English and French, readily discernable, prominently displayed and legible. This study examines the ease of finding and reading of mandatory label components on selected Canadian food products. A validated typographical scoring system assessed the lists of ingredients on a purposive sample of 100 food labels representing foods in all groups in Canada's Food Guide. Seven percent of the ingredient lists were easy to read; 26% were difficult to read and 67% were very difficult to read. Well-educated resourceful readers in consumer focus groups examined food labels for key elements that influence ease of finding and reading information. Focus groups and typographical scoring identified: colour contrast, case, print style, print size, space between the lines, reverse print, organization, justification, type of surface, hyphenation and print reproduction as factors that affect ease of reading. Print that curves around a container, lack of paragraphing or point form organization make reading difficult; text blocks at right angles to each other make comparisons difficult; separation of the nutrition facts table from the list of ingredients makes decision making tedious. Inadequate spacing between lines of print creates problems for readers of English and exacerbates problems for readers of French. Words placed over illustrations, busy backgrounds or watermarks increase reading difficulty. Hazard statements, instructions and storage information imbedded in other information without added space or appropriate heading is difficult to find and read. Canadian consumers echo consumers in 28 European countries who find label information difficult to find and to read and want clear guidelines/regulations on the placement and the typography of mandatory food label components [source] Ultrastructure of the tentacle nerve plexus and putative neural pathways in sea anemonesINVERTEBRATE BIOLOGY, Issue 3 2002Jane A. Westfall 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. [source] Perspectives of ammonite paleobiology from shell abnormalities in the genus BaculitesLETHAIA, Issue 3 2002R.A. HENDERSON Many Baculites specimens from the Upper Cretaceous of the United States Western Interior show exceptional preservation of the original aragonitic shell and its fine-scale surface ornamentation. Growth lines are ubiquitous, with two orders of these structures represented on some shells, and reflect the incremental addition of new shell at the apertural margin. Growth line interruption in the form of repair of minor shell damage at the aperture, commonplace in contemporary Nautilus, is essentially absent in Baculites, suggesting that its members fed on small prey in the water column. As typical of Mesozoic ammonites in general, and in striking contrast to contemporary Nautilus, no in vivo epizoans have been recognized on specimens of Baculites. It is inferred that the shell of Baculites was covered in periostracum to eliminate epizoic colonization. By analogy with Nautilus, a distinctive micro-ornament oriented at right angles to growth lines and visible on parts of some specimens was probably associated with periostracal attachment. A small proportion of Baculites specimens show abnormalities in shell growth categorized as v-shaped indentations of growth lines, shell grooves, fine-scale folds on the surface of growth lines and feather structures. We view this entire set of structures as due to abnormalities in mantle growth induced at the leading edge, impressed into the periostracum during its fabrication, and then in turn into the shell surface. As many of the Baculites with shell abnormalities are smooth, the proposal by Checa linking homologous structures recognized on other ammonites to the formation of comarginal ribs is rejected. A case of sutural inversion, in which the form of minor divisions of the major saddles and lobes are transposed, is recognized in a specimen of Baculites codyensis Reeside. We consider sutural pattern in ammonites, an expression of septal fluting, as replicating the genetically specified standing form of an elastic adapical visceral mass. The inverted sutural pattern, and by implication the style of septal fluting, was transcribed exactly in the three successive septa preserved on the specimen. The abnormality appears to be a case of homeotic mutation in which the plan for one body region becomes translocated to another. The conservatism of major elements of sutural (=septal) patterns for Mesozoic ammonites in their evolutionary spectrum suggests that a homeobox of conserved DNA sequence, with the transcription factors encoded in homeotic genes, is likely to have been involved. [source] Unique histological characteristics of Scedosporium that could aid in its identificationPATHOLOGY INTERNATIONAL, Issue 2 2010Masatomo Kimura Scedosporium prolificans has been increasingly recognized as an etiological agent of disseminated mycelial infections in profoundly immunocompromised patients. Reported herein is a case of disseminated S. prolificans infection in a patient undergoing anti-neoplastic chemotherapy for acute myeloid leukemia. Antemortem blood culture yielded S. prolificans, which was confirmed on conventional morphological examination and polymerase chain reaction-based DNA sequencing targeting internally transcribed spacer regions. Histopathology of autopsy specimens indicated fungal infection in the heart, lungs, liver, kidneys, spleen, pancreas and gastrointestinal tract, with the development of hemorrhagic and ischemic necrosis. The infecting fungus had developing septate hyphae and was identified as belonging to the genus Scedosporium, on in situ hybridization of tissue. The combination of haphazardly branching hyphae and lemon-shaped conidia appeared to be the most useful distinguishing features to allow differentiation of this fungus from other filamentous fungi in tissue. Three other unique histopathological characteristics of the fungus were noted: (i) parallel hyphae bridged at right angles to produce letter-H patterns; (ii) intravascular conidiation; and (iii) purple conidia in tissue, though these are usually described as brown in most text books. Precise histopathology, in addition to other techniques such as in situ hybridization, can aid in the identification of etiological fungi. [source] Ion dispersion near parallel wire grids in orthogonal acceleration time-of-flight mass spectrometry: predicting the effect of the approach angle on resolutionRAPID COMMUNICATIONS IN MASS SPECTROMETRY, Issue 6 2002Mark Lewin Ions experience small deflections in the vicinity of grids in accelerators and ion mirrors in time-of-flight (TOF) mass spectrometers. Recent experiments with an orthogonal acceleration (oa) TOF instrument have verified that the effect can significantly degrade resolution when ions approach grids at an angle deviating from 90,°. The phenomenon becomes significant only when ions have components of velocity at right angles to the wires of the grids. A model is presented in this study to predict this phenomenon for parallel wire grids. The fractional energy spread of ions (calculated in the static TOF-spectrometer frame of reference) scales directly with the approach angle of ions to the grid (as measured from normal approach). The energy spread also scales with the range of angles that is a consequence of the focusing effect in each gap between the wires of the grid. The equations imply that closely spaced parallel wire grids are best for deployment in oa-TOF systems where non-zero approach angles are unavoidable. Such grids are relatively impractical to manufacture and support but rectangular repeat cell grids with relatively few wires at right angles to the source axis are shown experimentally to introduce minimal energy spread. When these grids are rotated by 90,°, the resolution measured in a Q-TOF spectrometer is degraded in approximate agreement with the parallel wire model. A practical implication of this work is that grid transmissions in oa-TOF systems may be significantly increased without loss of resolution. Improvements of ,200% (V-mode) and ,400% (W-mode) in ion transmission were obtained in this study without compromising resolution. This was achieved with ,73% transmission grids and greater potential improvements in transmission are being realised since this study with ,89% transmission grids having similar geometry. Copyright © 2002 John Wiley & Sons, Ltd. [source] An oximino tautomer of 1- n -decyl-4-hydroxyimino-3-methyl-1H -pyrazol-5(4H)-oneACTA CRYSTALLOGRAPHICA SECTION C, Issue 2 2006Ricardo Baggio The title compound, C14H25N3O2, consists of a five-membered heterocyclic ring to which a pendant decyl group is attached. The oximino tautomeric character of the molecule is clearly defined by the distribution of well defined double bonds in the heterocycle region (one C=O and two C=N). The most conspicuous packing interaction is the strong intermolecular hydrogen bond linking the oximino OH group and the carbonyl O atom to define broad planar hydrophilic strips running along the unique b axis. The alkyl chains adopt a fully extended conformation and lie almost at right angles to these one-dimensional structures, defining their hydrophobic counterpart. [source] Rotafolia songziensis gen. et comb. nov., a sphenopsid from the Late Devonian of Hubei, ChinaBOTANICAL JOURNAL OF THE LINNEAN SOCIETY, Issue 1 2005DE-MING WANG A sphenopsid from the Upper Devonian (Famennian) Xiejingsi Formation, south-western Hubei Province, China, previously named as various species in Sphenophyllum, Hamatophyton, Bowmanites and Sphenophyllostachys, is now reinvestigated and assigned to a new taxon, Rotafolia songziensis gen. et comb. nov. Its ribbed axes are anisotomous and possess slightly expanded nodes. Lateral axes are inserted at nodes on main axes. Whorls of much divided vegetative leaves are attached at nearly right angles to nodes of basal axes, and at acute angles to nodes of terminal axes. There are six leaves per whorl. The terminal strobilus includes a central axis and verticils of fertile units. Each fertile unit consists of a bract and numerous sporangia. The margin of the elongate-cuneate bract bears a distal and many lateral elongate segments. Clusters of elongate sporangia are abaxially attached to the base of the bract at the same level. The axis has an actinostele, composed of a three-ribbed, exarch primary xylem and radial secondary xylem. Although Rotafolia songziensis closely resembles Hamatophyton verticillatum in axis character, leaf morphology and primary xylem type, they are quite different in strobilar structure. Taxonomically, Rotafolia is placed in the order Sphenophyllales by three well-defined characters: 1) whorled appendages; 2) ribbed protosteles; 3) exarch primary xylem maturation. © 2005 The Linnean Society of London, Botanical Journal of the Linnean Society, 2005, 148, 21,37. [source] Hsüa deflexa sp. nov. from the Xujiachong Formation (Lower Devonian) of eastern Yunnan, ChinaBOTANICAL JOURNAL OF THE LINNEAN SOCIETY, Issue 3 2003DE-MING WANG A new vascular plant, Hsüa deflexa sp. nov., is documented from the Lower Devonian ((upper) Pragian-lower Emsian) Xujiachong Formation, near Xujiachong village, Qujing District, eastern Yunnan, South China. In three dimensions, the branching system comprises a robust creeping main axis and comparatively slender erect lateral axes inserted oppositely or alternately. The lateral axes depart at right angles from the main axis. Towards the apex, the main axis is perhaps erect with the lateral axes attached at smaller angles. The lateral axes dichotomize equally one to three times in different planes and decrease in diameter and length acropetally. They bear sparse and irregular tiny spines. Apices of a pair of distal lateral axes curve in opposite directions and each terminates in a rounded to reniform sporangium. The sporangium dehisces into two equal valves along an indistinct convex marginal thickening. The xylem is possibly centrarch. This plant fits Hsüa in branching pattern, sporangial characters and xylem maturation. Hsüa deflexa sp. nov. differs mainly from the type species H. robusta in the presence of axial spines, perpendicular extension of lateral axes from the main axis and curving of distal lateral axes. Based on the possibly centrarch xylem and terminal sporangium, this plant relates to the rhyniophytes (sensu Banks, 1968). In view of the equal sporangial valves with marginal thickenings it resembles the zosterophyllophytes (sensu Banks, 1968). Hsüa is now treated as incertae sedis. © 2003 The Linnean Society of London, Botanical Journal of the Linnean Society, 2003, 142, 255,271. [source] Method for coronary angiography in morbidly obese patientsCATHETERIZATION AND CARDIOVASCULAR INTERVENTIONS, Issue 2 2005William G. Kussmaul III MD Abstract Cardiac catheterization in morbidly obese patients is difficult. In addition to problems regarding vascular access and radiographic penetration of the chest, the engineering parameters and physical limitations of the table and its supporting structures may limit these patients' ability to undergo clinically indicated coronary angiography. We describe a method for cardiac catheterization in which much of the obese patient's body weight is supported on a stretcher placed at right angles to the catheterization table, with only the thorax on the table under the image intensifier. Using this method, five consecutive successful diagnostic procedures and one coronary stent procedure have been performed without complication. Limitations of this procedure include inability to achieve the normal variety of angiographic views due to constraints on image intensifier rotation and skew. © 2005 Wiley-Liss, Inc. [source] | ||||||||||||||||