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Subsequent Stages (subsequent + stage)
Selected AbstractsCrescent Versus Rectangle: Is It a True Negative Margin in Second and Subsequent Stages of Mohs Surgery?DERMATOLOGIC SURGERY, Issue 2 2010YUE YU MD BACKGROUND The hallmark of Mohs micrographic surgery is using tangential tissue sections that theoretically allow 100% of the tissue margin to be examined, but when taking additional layers for second and subsequent Mohs stages, no detailed methods have been described to ensure that 100% of the tissue margins are analyzed. METHOD A rectangular or a crescent-shaped layer is often used to take second and subsequent stages. Here we compare the two techniques for their theoretic advantages and disadvantages. SUMMARY The advantage of the rectangular shape has been ease of processing, as well as built in vertical "nicks" that automatically mark the border of the tissue removed, but the rectangular layer may not provide 100% evaluation of the tumor margin because the vertical edges of the rectangular layer are not always completely analyzed, and thus tumor cells cannot be visualized in the vertical margins of these layers. This might result in a false-negative margin reading, which can be avoided by using the crescent layer. CONCLUSION We propose taking second and subsequent Mohs layers with only a crescent shape, which allows true 100% tissue margin assessment. The authors have indicated no significant interest with commercial supporters. [source] MS3 using the collision cell of a tandem mass spectrometer systemRAPID COMMUNICATIONS IN MASS SPECTROMETRY, Issue 11 2002Lisa M. Cousins We report the feasibility of multistage fragmentation in combination with a fast background subtraction method, yielding the equivalent of MS3. The first quadrupole selects an ion of interest, and the ion is axially accelerated into Q2 to generate fragment ions. Subsequent stages of mass selection and fragmentation are obtained by quadrupolar resonant excitation within the Q2 collision cell. The fragments are analyzed downstream by either a resolving quadrupole or a time-of-flight (TOF) mass spectrometer, and multistage spectra are obtained by subtraction (MSn,,,MSn,1) for n,=,3 or 4. We discuss the characterization of this method, including product ion arrival times, fragmentation efficiencies, and ion selectivity. We report accurate TOF mass spectra of background-subtracted MS3 for protonated molecules reserpine (m/z 609), bosentan (m/z 1552), and taxol (m/z 854). Copyright © 2002 John Wiley & Sons, Ltd. [source] Determination of Gradient and Curvature Constrained Optimal PathsCOMPUTER-AIDED CIVIL AND INFRASTRUCTURE ENGINEERING, Issue 1 2006Michael J. De Smith Initially, we examine the case of a single (global) gradient constraint and a planar surface, with or without boundaries and obstacles. This leads to a consideration of surface representation using rectangular lattices and procedures for determining shortest gradient-constrained paths across such surfaces. Gradient-constrained distance transforms are introduced as a new procedure to enable such optimal paths to be computed, and examples are provided for a range of landform profiles and gradients. Horizontal and vertical curvature constraints are then analyzed and incorporated into final solution paths at subsequent stages of the optimization process. Such paths may then be used as preanalyzed input to detailed cost and engineering models to speed up, and where possible improve, the quality and cost-effectiveness of route selection. [source] Using GIS, Genetic Algorithms, and Visualization in Highway DevelopmentCOMPUTER-AIDED CIVIL AND INFRASTRUCTURE ENGINEERING, Issue 6 2001Manoj K. Jha A model for highway development is presented, which uses geographic information systems (GIS), genetic algorithms (GA), and computer visualization (CV). GIS serves as a repository of geographic information and enables spatial manipulations and database management. GAs are used to optimize highway alignments in a complex search space. CV is a technique used to convey the characteristics of alternative solutions, which can be the basis of decisions. The proposed model implements GIS and GA to find an optimized alignment based on the minimization of highway costs. CV is implemented to investigate the effects of intangible parameters, such as unusual land and environmental characteristics not considered in optimization. Constrained optimization using GAs may be performed at subsequent stages if necessary using feedback received from CVs. Implementation of the model in a real highway project from Maryland indicates that integration of GIS, GAs, and CV greatly enhances the highway development process. [source] Crescent Versus Rectangle: Is It a True Negative Margin in Second and Subsequent Stages of Mohs Surgery?DERMATOLOGIC SURGERY, Issue 2 2010YUE YU MD BACKGROUND The hallmark of Mohs micrographic surgery is using tangential tissue sections that theoretically allow 100% of the tissue margin to be examined, but when taking additional layers for second and subsequent Mohs stages, no detailed methods have been described to ensure that 100% of the tissue margins are analyzed. METHOD A rectangular or a crescent-shaped layer is often used to take second and subsequent stages. Here we compare the two techniques for their theoretic advantages and disadvantages. SUMMARY The advantage of the rectangular shape has been ease of processing, as well as built in vertical "nicks" that automatically mark the border of the tissue removed, but the rectangular layer may not provide 100% evaluation of the tumor margin because the vertical edges of the rectangular layer are not always completely analyzed, and thus tumor cells cannot be visualized in the vertical margins of these layers. This might result in a false-negative margin reading, which can be avoided by using the crescent layer. CONCLUSION We propose taking second and subsequent Mohs layers with only a crescent shape, which allows true 100% tissue margin assessment. The authors have indicated no significant interest with commercial supporters. [source] The Epigenesis of the Family System as a Context for Individual DevelopmentFAMILY PROCESS, Issue 3 2002Herta A. Guttman M.D. In this article, the concept introduced by Lyman Wynne, that the individual develops epigenetically within the family system, is discussed and validated with data from a study of the characteristics and relationships of 27 women with borderline personality disorder and their parents. Each stage of the epigenetic process is impaired in one way or another, adversely affecting subsequent stages. Early impairment of attachment-care-giving processes is at least partly attributable to a lack of empathic parenting; effective communication is marred by family members' inability to experience or express feelings (alexithymia); this, in turn, makes it difficult to engage in joint family problem solving. Mutuality between family members does not occur in such a context, and there is an absence of intimacy between family members. These are often abusive family systems, with multiple abuse and intrafamilial sexual abuse more specifically directed at the daughter with BPD. The symptoms of the daughter can be understood systemically, as representing both predispositional characteristics and reactions to the family system. It is suggested that the epigenetic paradigm could be used to characterize the specific failure of developmental processes in many different disorders. [source] Biochemical and molecular characterization of a laccase from the edible straw mushroom, Volvariella volvaceaFEBS JOURNAL, Issue 2 2004Shicheng Chen We have isolated a laccase (lac1) from culture fluid of Volvariella volvacea, grown in a defined medium containing 150 µm CuSO4, by ion-exchange and gel filtration chromatography. Lac1 has a molecular mass of 58 kDa as determined by SDS/PAGE and an isoelectric point of 3.7. Degenerate primers based on the N-terminal sequence of purified lac1 and a conserved copper-binding domain were used to generate cDNA fragments encoding a portion of the lac1 protein and RACE was used to obtain full-length cDNA clones. The cDNA of lac1 contained an ORF of 1557 bp encoding 519 amino acids. The amino acid sequence from Ala25 to Asp41 corresponded to the N-terminal sequence of the purified protein. The first 24 amino acids are presumed to be a signal peptide. The expression of lac1 is regulated at the transcription level by copper and various aromatic compounds. RT-PCR analysis of gene transcription in fungal mycelia grown on rice-straw revealed that, apart from during the early stages of substrate colonization, lac1 was expressed at every stage of the mushroom developmental cycle defined in this study, although the levels of transcription varied considerably depending upon the developmental phase. Transcription of lac1 increased sharply during the latter phase of substrate colonization and reached maximum levels during the very early stages (primordium formation, pinhead stage) of fruit body morphogenesis. Gene expression then declined to ,,20,30% of peak levels throughout the subsequent stages of sporophore development. [source] Computational form-finding of tension membrane structures,Non-finite element approaches: Part 1.INTERNATIONAL JOURNAL FOR NUMERICAL METHODS IN ENGINEERING, Issue 5 2003Use of cubic splines in finding minimal surface membranes Abstract This paper, presented in three parts, discusses a computational methodology for form-finding of tension membrane structures (TMS), or fabric structures, used as roofing forms. The term ,form-finding' describes a process of finding the shape of a TMS under its initial tension. Such a shape is neither known a priori, nor can it be described by a simple mathematical function. The work is motivated by the need to provide an efficient numerical tool, which will allow a better integration of the design/analysis/manufacture of TMS. A particular category of structural forms is considered, known as minimal surface membranes (such as can be reproduced by soap films). The numerical method adopted throughout is dynamic relaxation (DR) with kinetic damping. Part 1 describes a new form-finding approach, based on the Laplace,Young equation and cubic spline fitting to give a full, piecewise, analytical description of a minimal surface. The advantages arising from the approach, particularly with regard to manufacture of cutting patterns for a membrane, are highlighted. Part 2 describes an alternative and novel form-finding approach, based on a constant tension field and faceted (triangular mesh) representation of the minimal surface. It presents techniques for controlling mesh distortion and discusses effects of mesh control on the accuracy and computational efficiency of the solution, as well as on the subsequent stages in design. Part 3 gives a comparison of the performance of the initial method (Part 1) and the faceted approximations (Part 2). Functional relations, which encapsulate the numerical efficiency of each method, are presented. Copyright © 2002 John Wiley & Sons, Ltd. [source] Computational form-finding of tension membrane structures,Non-finite element approaches: Part 2.INTERNATIONAL JOURNAL FOR NUMERICAL METHODS IN ENGINEERING, Issue 5 2003Triangular mesh discretization, control of mesh distortion in modelling minimal surface membranes Abstract This paper, presented in three parts, discusses a computational methodology for form-finding of tension membrane structures (TMS), or fabric structures, used as roofing forms. The term ,form-finding' describes a process of finding the shape of a TMS under its initial tension. Such a shape is neither known a priori, nor can it be described by a simple mathematical function. The work is motivated by the need to provide an efficient numerical tool, which will allow a better integration of the design/analysis/manufacture of TMS. A particular category of structural forms is considered, known as minimal surface membranes (such as can be reproduced by soap films). The numerical method adopted throughout is dynamic relaxation (DR) with kinetic damping. Part 1 gave a background to the problem of TMS design, described the DR method, and presented a new form-finding methodology, based on the Laplace,Young equation and cubic spline fitting to give a full, piecewise, analytical description of the surface. Part 2 describes an alternative and novel form-finding method, based on a constant tension field and faceted (triangular mesh) representation of the minimal surface. Techniques for controlling mesh distortion are presented, and their effects on the accuracy and computational efficiency of the solution, as well as on the subsequent stages in design, are examined. Part 3 gives a comparison of the performance of the initial method (Part 1) and the faceted approximations (Part 2). Functional relations, which encapsulate the numerical efficiency of each method, are presented. Copyright © 2002 John Wiley & Sons, Ltd. [source] Patterns of mortality for each life-history stage in a population of the endangered New Zealand stitchbirdJOURNAL OF ANIMAL ECOLOGY, Issue 4 2009Matthew Low Summary 1Using data from 396 breeding attempts over an 8-year period, we investigated age- and stage-specific survival rates and their modifying factors in a closed island population of the New Zealand stitchbird (or hihi, Notiomystis cincta Du Bus). 2Survival probability generally increased over time; however, at each life-history transition, survival in the new stage started lower than at the end of the previous stage, creating a ,saw-tooth' function of age-related survival. 3The probability of an egg hatching was low (0·73 ± 0·01): most likely a consequence of genetic bottlenecks previously endured by this population. There was strong support for a positive relationship between hatching rate and the subsequent survival of the female parent, and hatching success declining for females > 4 years old. 4Nestling survival probability increased as a function of brood size and days since hatching, and decreased relative to daily maximum ambient temperature and hatching date. Support for models including ambient temperature was greater than for other covariates, with the majority of this temperature-mediated survival effect being restricted to the early nestling stage. 5Fledglings had low survival rates in the first two weeks after leaving the nest, with post-fledging survival related to the fledgling's mass. Two months after fledging, juvenile survival probability plateaued and remained relatively constant for the following autumn, winter and spring/summer breeding season. There was no effect of sex or season on adult survival probability. However, there was strong support for age-specific variation in adult survival, with survival likelihood increasing during the first four years before showing evidence of a senescence decline. 6Within-stage survival increases were likely related to stage-specific selection pressures initially weeding out individuals of poorer phenotypes for the environment specific to each life-history stage. Such a mechanism explains the initial high mortality at life-history transitions; a well-adapted phenotype for one stage may not necessarily be so well adapted for subsequent stages. These patterns are not only valuable for examining life-history theory, but also for understanding the regulation of vital rates in an endangered species and providing a basis from which better population management models and harvesting regimes can be derived. [source] Simultaneous separation and identification of oligomeric procyanidins and anthocyanin-derived pigments in raw red wine by HPLC-UV-ESI-MSnJOURNAL OF MASS SPECTROMETRY (INCORP BIOLOGICAL MASS SPECTROMETRY), Issue 7 2006S. Pati Abstract Samples of raw red wine (Primitivo di Manduria, Apulia, Southern Italy) were analysed without any pre-treatment (except 1 : 2 dilution with water) using HPLC with detection based on UV absorbance and Electrospray Ionisation Sequential Mass Spectrometry (ESI-MSn, with n = 1,3) in a series configuration. In particular, absorbance at 520 nm was monitored for UV detection in order to identify pigments responsible for wine colour. On the other hand, two subsequent stages of MS detection based on positive ions were adopted. The first consisted of an explorative MS acquisition, aimed at the individuation of the m/z ratios for positively charged compounds; the second was based on fragmentation of the detected ions within an ion trap analyser, followed by MS/MS and, if required, MS3 acquisitions. The synergy between UV detection and MSn analysis led to the identification of 41 pigments, which can be classified into five groups: grape anthocyanins, pyranoanthocyanins, vinyl-linked anthocyanin-flavanol pigments, ethyl-bridged anthocyanin-flavanol pigments and flavanol-anthocyanin compounds. Many isomeric and oligomeric structures were found within each group. A further class of compounds, not absorbing in the visible spectrum, could be also characterised by ESI-MSn and corresponded to B-type procyanidins, i.e. proanthocyanidins arising from C4,C8/C4,C6 couplings between catechin or epicatechin units. In particular, oligomeric structures (from dimers to pentamers), often present with several isomers, were identified and their fragmentation patterns clarified. Copyright © 2006 John Wiley & Sons, Ltd. [source] Analysis of the requirements for pilus biogenesis at the outer membrane usher and the function of the usher C-terminusMOLECULAR MICROBIOLOGY, Issue 2 2006Stephane Shu Kin So Summary Uropathogenic strains of Escherichia coli assemble type 1 and P pili to colonize the bladder and kidney respectively. These pili are prototype structures assembled by the chaperone/usher secretion pathway. In this pathway, a periplasmic chaperone works together with an outer membrane (OM) usher to control the folding of pilus subunits, their assembly into a pilus fibre and secretion of the fibre to the cell surface. The usher serves as the assembly and secretion platform in the OM. The usher has distinct functional domains, with the N-terminus providing the initial targeting site for chaperone,subunit complexes and the C-terminus required for subsequent stages of pilus biogenesis. In this study, we investigated the molecular interactions occurring at the usher during pilus biogenesis and the function of the usher C-terminus. We provide genetic and biochemical evidence that the usher functions as a complex in the OM and that interaction of the pilus adhesin with the usher is critical to prime the usher for pilus biogenesis. Analysis of C-terminal truncation and substitution mutants of the P pilus usher PapC demonstrated that the C-terminus is required for proper binding of chaperone,subunit complexes to the usher and plays an important role in assembly of complete pili. [source] Looking for faces: Attention modulates early occipitotemporal object processingPSYCHOPHYSIOLOGY, Issue 3 2004Andreas Lueschow Abstract Looking for somebody's face in a crowd is one of the most important examples of visual search. For this goal, attention has to be directed to a well-defined perceptual category. When this categorically selective process starts is, however, still unknown. To this end, we used magnetoencephalography (MEG) recorded over right human occipitotemporal cortex to investigate the time course of attentional modulation of perceptual processes elicited by faces and by houses. The first face-distinctive MEG response was observed at 160,170 ms (M170). Nevertheless, attention did not start to modulate face processing before 190 ms. The first house-distinctive MEG activity was also found around 160,170 ms. However, house processing was not modulated by attention before 280 ms (90 ms later than face processing). Further analysis revealed that the attentional modulation of face processing is not due to later, for example, back-propagated activation of the M170 generator. Rather, subsequent stages of occipitotemporal object processing were modulated in a category-specific manner and with preferential access to face processing. [source] Trypsin enzyme activity during larval development of Litopenaeus vannamei (Boone) fed on live feedsAQUACULTURE RESEARCH, Issue 5 2002A C Puello-Cruz Abstract Larval stages of the Pacific white shrimp, Litopenaeus vannamei (Boone) were fed standard live diets of mixed microalgae from the first to the third protozoea (PZ1 to PZ3), followed by Artemia nauplii until post-larvae 1 (PL1). Trypsin enzyme activity for each larval stage was determined using N -,-p-toluenesulphonyl- l -arginine methyl ester (TAME) as a substrate. Results were expressed as enzyme content to assess ontogenetic changes during larval development. Tissue trypsin content (IU µg,1 DW for each larval stage) was significantly highest at the PZ1 stage and declined through subsequent stages to PL1. This contrasts with previously observed patterns of trypsin development in Litopenaeus setiferus (Linnaeus) and other penaeid genera, which exhibit a peak in trypsin activity at the third protozoea/first mysis (PZ3/M1) larval stage. Litopenaeus vannamei larvae transferred to a diet of Artemia at the beginning of the second protozoea (PZ2) stage were significantly heavier on reaching the first mysis stage (M1) than those fed algae, while survival was not significantly different between treatments. At both PZ2 and PZ3 stages, trypsin content in larvae feeding on Artemia was significantly lower than in those feeding on algae. The rapid decline in trypsin content from PZ1 and the flexible enzyme response from PZ2 suggest that L. vannamei is physiologically adapted to transfer to a more carnivorous diet during the mid-protozoeal stages. 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