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Sufficient
Kinds of Sufficient Terms modified by Sufficient Selected AbstractsReducing the Incidence of Denture Stomatitis: Are Denture Cleansers Sufficient?JOURNAL OF PROSTHODONTICS, Issue 4 2010Anto Jose MSc Abstract Purpose:,Candida albicans is the predominant oral yeast associated with denture stomatitis. With an increasing population of denture wearers, the incidence of denture stomatitis is increasing. Effective management of these patients will alleviate the morbidity associated with this disease. The aim of this study was to examine the capacity of four denture cleansers to efficiently decontaminate and sterilize surfaces covered by C. albicans biofilms. Materials and Methods: Sixteen C. albicans strains isolated from denture stomatitis patients and strain ATCC 90028 were grown as mature confluent biofilms on a 96-well format and immersed in Dentural, MedicalÔ Interporous®, Steradent Active Plus, and Boots Smile denture cleansers according to the manufacturers' instructions or overnight. The metabolic activity and biomass of the biofilms were then quantified, and scanning electron microscopy (SEM) used to examine treated biofilms. Results: Dentural was the most effective denture cleanser, reducing the biomass by greater than 90% after 20 minutes. Steradent Active plus was significantly more effective following 10-minute immersion than overnight (p < 0.001). All cleansers reduced the metabolic activity by greater than 80% following overnight immersion; however, Boots Smile exhibited significantly reduced metabolic activity following only a 15-minute immersion (p < 0.001). SEM revealed residual C. albicans material following Dentural treatment. Conclusions: This study showed that denture cleansers exhibit effective anti- C. albicans biofilm activity, both in terms of removal and disinfection; however, residual biofilm retention that could lead to regrowth and denture colonization was observed. Therefore, alternative mechanical disruptive methods are required to enhance biofilm removal. [source] G. Stanley Hall: Neither Psychology Alone Nor Basic Research is SufficientJOURNAL OF RESEARCH ON ADOLESCENCE, Issue 4 2005James Youniss In his monumental work, Adolescence, G. Stanley Hall showed the value of interdisciplinary scholarship and respect for research, which had a policy orientation. Over the course of the 20th century these two characteristics faded in adolescent studies as psychology took dominance and basic research was given priority over policy considerations. An argument is made that there is value in revisiting Hall's approach as studies of adolescence can be enriched through interdisciplinary efforts and research which brings policy to the forefront. [source] Thematic Issue: Rare Earth Resources: Are They Sufficient or Deficient?RESOURCE GEOLOGY, Issue 4 2008Yasushi Watanabe No abstract is available for this article. [source] A Single Molecular Beacon Probe Is Sufficient for the Analysis of Multiple Nucleic Acid SequencesCHEMBIOCHEM, Issue 12 2010Yulia V. Gerasimova Dr. Abstract Molecular beacon (MB) probes are dual-labeled hairpin-shaped oligodeoxyribonucleotides that are extensively used for real-time detection of specific RNA/DNA analytes. In the MB probe, the loop fragment is complementary to the analyte: therefore, a unique probe is required for the analysis of each new analyte sequence. The conjugation of an oligonucleotide with two dyes and subsequent purification procedures add to the cost of MB probes, thus reducing their application in multiplex formats. Here we demonstrate how one MB probe can be used for the analysis of an arbitrary nucleic acid. The approach takes advantage of two oligonucleotide adaptor strands, each of which contains a fragment complementary to the analyte and a fragment complementary to an MB probe. The presence of the analyte leads to association of MB probe and the two DNA strands in quadripartite complex. The MB probe fluorescently reports the formation of this complex. In this design, the MB does not bind the analyte directly; therefore, the MB sequence is independent of the analyte. In this study one universal MB probe was used to genotype three human polymorphic sites. This approach promises to reduce the cost of multiplex real-time assays and improve the accuracy of single-nucleotide polymorphism genotyping. [source] The Presence of a Ferrocenyl Unit on an Estrogenic Molecule is Not Always Sufficient to Generate in,vitro CytotoxicityCHEMMEDCHEM, Issue 11 2006Anne Vessières Dr. Abstract We recently reported the dual (antihormonal and cytotoxic) functionality of ferrocifens, which are organometallic complexes derived from hydroxytamoxifen, the standard molecule in the treatment of hormone-dependent breast cancers. To test the hypothesis that the presence of a ferrocenyl substituent on molecules with an affinity for the estrogen receptor is sufficient to give them cytotoxic properties in,vitro, we prepared complexes derived from estradiol with a ferrocenyl substituent at positions 7, and 17,. The complexes thus obtained retain a satisfactory level of affinity for the estrogen receptor (RBA values higher than 12,%). At low concentrations (0.1,1,,M) the complexes show an estrogenic effect in,vitro equivalent to that of estradiol on hormone-dependent (MCF-7) breast cancer cells, and no cytotoxic effect on hormone-independent (MDA-MB-231) breast cancer cells. At high concentrations (up to 50,,M) the 17, -ethynylferrocenyl estradiol and 7, -ferrocenylmethylthio estradiol become cytotoxic (IC50=13.2,,M and 18.8,,m, respectively) while the 17, -ferrocenylestradiol remains non toxic. The low toxicity of these compounds support our hypothesis that electronic communication between the ferrocenyl and phenol moieties in the hydroxyferrocifens series is a key parameter in the generation of cytotoxic effects at submicromolar concentrations. [source] Growth hormone in short children: beyond medicine?ACTA PAEDIATRICA, Issue 1 2001LLE Bolt The indications for growth hormone (GH) treatment in non-GH-deficient short children are in debate, with some arguing that this treatment does not belong solely in the medical domain. We describe three different approaches to the issue, and argue that neither a disease-oriented nor client-oriented approach is sufficient. Both lead to withdrawal of medical interventions or to an undesirable application. Conclusion: An approach focusing on suffering as an indication for treatment of short stature is the most appropriate. The challenge is to develop proper tools by which to evaluate suffering and the efficacy of GH treatment in these children in order to relieve or prevent suffering. [source] Hierarchical Convex Approximation of 3D Shapes for Fast Region SelectionCOMPUTER GRAPHICS FORUM, Issue 5 2008Marco Attene Abstract Given a 3D solid model S represented by a tetrahedral mesh, we describe a novel algorithm to compute a hierarchy of convex polyhedra that tightly enclose S. The hierarchy can be browsed at interactive speed on a modern PC and it is useful for implementing an intuitive feature selection paradigm for 3D editing environments. Convex parts often coincide with perceptually relevant shape components and, for their identification, existing methods rely on the boundary surface only. In contrast, we show that the notion of part concavity can be expressed and implemented more intuitively and efficiently by exploiting a tetrahedrization of the shape volume. The method proposed is completely automatic, and generates a tree of convex polyhedra in which the root is the convex hull of the whole shape, and the leaves are the tetrahedra of the input mesh. The algorithm proceeds bottom-up by hierarchically clustering tetrahedra into nearly convex aggregations, and the whole process is significantly fast. We prove that, in the average case, for a mesh of n tetrahedra O(n log2 n) operations are sufficient to compute the whole tree. [source] Diorama Construction From a Single ImageCOMPUTER GRAPHICS FORUM, Issue 3 2007J. Assa Abstract Diorama artists produce a spectacular 3D effect in a confined space by generating depth illusions that are faithful to the ordering of the objects in a large real or imaginary scene. Indeed, cognitive scientists have discovered that depth perception is mostly affected by depth order and precedence among objects. Motivated by these findings, we employ ordinal cues to construct a model from a single image that similarly to Dioramas, intensifies the depth perception. We demonstrate that such models are sufficient for the creation of realistic 3D visual experiences. The initial step of our technique extracts several relative depth cues that are well known to exist in the human visual system. Next, we integrate the resulting cues to create a coherent surface. We introduce wide slits in the surface, thus generalizing the concept of cardboard cutout layers. Lastly, the surface geometry and texture are extended alongside the slits, to allow small changes in the viewpoint which enriches the depth illusion. [source] Wrinkling Coarse Meshes on the GPUCOMPUTER GRAPHICS FORUM, Issue 3 2006J. Loviscach The simulation of complex layers of folds of cloth can be handled through algorithms which take the physical dynamics into account. In many cases, however, it is sufficient to generate wrinkles on a piece of garment which mostly appears spread out. This paper presents a corresponding fully GPU-based, easy-to-control, and robust method to generate and render plausible and detailed folds. This simulation is generated from an animated mesh. A relaxation step ensures that the behavior remains globally consistent. The resulting wrinkle field controls the lighting and distorts the texture in a way which closely simulates an actually deformed surface. No highly tessellated mesh is required to compute the position of the folds or to render them. Furthermore, the solution provides a 3D paint interface through which the user may bias the computation in such a way that folds already appear in the rest pose. Categories and Subject Descriptors (according to ACM CCS): I.3.7 [Computer Graphics]: Animation, I.3.7 [Computer Graphics]: Color, shading, shadowing, and texture [source] The embedded ion method: A new approach to the electrostatic description of crystal lattice effects in chemical shielding calculationsCONCEPTS IN MAGNETIC RESONANCE, Issue 5 2006Dirk Stueber Abstract The nuclear magnetic shielding anisotropy of NMR active nuclei is highly sensitive to the nuclear electronic environment. Hence, measurements of the nuclear magnetic shielding anisotropy represent a powerful tool in the elucidation of molecular structure for a wide variety of materials. Quantum mechanical ab initio nuclear magnetic shielding calculations effectively complement the experimental NMR data by revealing additional structural information. The accuracy and capacity of these calculations has been improved considerably in recent years. However, the inherent problem of the limitation in the size of the systems that may be studied due to the relatively demanding computational requirements largely remains. Accordingly, ab initio shielding calculations have been performed predominantly on isolated molecules, neglecting the molecular environment. This approach is sufficient for neutral nonpolar systems, but leads to serious errors in the shielding calculations on polar and ionic systems. Conducting ab initio shielding calculations on clusters of molecules (i.e., including the nearest neighbor interactions) has improved the accuracy of the calculations in many cases. Other methods of simulating crystal lattice effects in shielding calculations that have been developed include the electrostatic representation of the crystal lattice using point charge arrays, full ab initio methods, ab initio methods under periodic boundary conditions, and hybrid ab initio/molecular dynamics methods. The embedded ion method (EIM) discussed here follows the electrostatic approach. The method mimics the intermolecular and interionic interactions experienced by a subject molecule or cluster in a given crystal in quantum mechanical shielding calculations with a large finite, periodic, and self-consistent array of point charges. The point charge arrays in the EIM are generated using the Ewald summation method and embed the molecule or ion of interest for which the ab initio shielding calculations are performed. The accuracy with which the EIM reproduces experimental nuclear magnetic shift tensor principal values, the sensitivity of the EIM to the parameters defining the point charge arrays, as well as the strengths and limitations of the EIM in comparison with other methods that include crystal lattice effects in chemical shielding calculations, are presented. © 2006 Wiley Periodicals, Inc. Concepts Magn Reson Part A 28A: 347,368, 2006 [source] Design of an MR-compatible piezoelectric actuator for MR elastographyCONCEPTS IN MAGNETIC RESONANCE, Issue 4 2002Kai Uffmann Abstract Magnetic Resonance (MR) elastography is a method for measuring tissue elasticity via phase images acquired with an MR scanner. The propagation of periodic mechanical waves through the tissue can be captured by means of a modified phase contrast sequence. These waves are generated with a mechanical oscillator (actuator) and coupled into the tissue through the skin. The actuator must be capable of generating a sinusoidal excitation with excellent phase and amplitude stability, while not disturbing the MR imaging process. In this work, an actuator based on a piezoelectric principle was developed. Based on the imaging evaluation of several material samples, the housing for the piezoelectric ceramic was constructed of aluminum. Smaller parts of the housing were manufactured from brass and titanium to fulfill the mechanical constraints. A lever was used to transfer the oscillation generated by the piezoelectric ceramic to the point of excitation. The lever amplifies the piezoelectric motion, allowing for a more compact design. Three different lever designs were characterized by an acceleration sensor both outside and inside the magnet. It was shown that the rigidity of the lever, as determined by its material and form, was decisive in determining the resonant frequency of the system and therefore the maximum practical frequency of operation. It was also shown that the motion of the oscillator is unaffected by the electromagnetic fields of the MR imager. The final design can be placed directly in the magnet bore within a few centimeters of the tissue volume to be imaged without generating significant artifacts. An amplitude range of 0,1 mm in the frequency range from 0 to over 300 Hz was achieved, sufficient for performing most MR elastography applications. © 2002 Wiley Periodicals, Inc. Concepts in Magnetic Resonance (Magn Reson Engineering) 15: 239,254, 2002 [source] Preventing the Spread of Invasive Species: Economic Benefits of Intervention Guided by Ecological PredictionsCONSERVATION BIOLOGY, Issue 1 2008REUBEN P. KELLER bioeconomía; economía de las invasiones; invasiones biológicas; Orconectes rusticus; predicciones ecológicas Abstract:,Preventing the invasion of freshwater aquatic species is the surest way to reduce their impacts, but it is also often expensive. Hence, the most efficient prevention programs will rely on accurate predictions of sites most at risk of becoming invaded and concentrate resources at those sites. Using data from Vilas County, Wisconsin (U.S.A.), collected in the 1970s, we constructed a predictive occurrence model for rusty crayfish (Orconectes rusticus) and applied it to an independent data set of 48 Vilas County lakes to predict which of these were most likely to become invaded between 1975 and 2005. We nested this invasion model within an economic framework to determine whether targeted management, derived from our quantitative predictions of likely invasion sites, would increase the economic value of lakes in the independent data set. Although the optimum expenditure on lake protection was high, protecting lakes at this level would have produced net economic benefits of at least $6 million over the last 30 years. We did not attempt to determine the value of nonmarket benefits of protection; thus, our results are likely to underestimate the total benefits from preventing invasions. Our results demonstrate that although few data are available early in an invasion, these data may be sufficient to support targeted, effective, and economically rational management. In addition, our results show that ecological predictions are becoming sufficiently accurate that their application in management can produce net economic benefits. Resumen:,La prevención de la invasión de especies dulceacuícolas es la manera más segura de reducir sus impactos, pero a menudo es costosa. Por lo tanto, los programas de prevención más eficientes dependerán de predicciones precisas de los sitios con mayor riesgo de ser invadidos y concentrarán recursos en esos sitios. Utilizando datos recolectados en los 70s en el Condado Vilas, Wisconsin (E.U.A.), desarrollamos un modelo predictivo de la ocurrencia de Orconectes rusticus y lo aplicamos en un conjunto de datos independientes de 48 lagos en el Condado de Vilas para predecir cuales fueron más susceptibles de ser invadidos entre 1975 y 2005. Anidamos este modelo de invasión en un marco económico para determinar si los objetivos de manejo, derivados de nuestras predicciones cuantitativas de sitios susceptibles a la invasión, incrementarían el valor económico de los lagos del conjunto independiente de datos. Aunque el gasto óptimo para la protección de lagos fue alto, la protección de lagos a este nivel podría haber producido beneficios económicos por un mínimo de $6 millones en los últimos 30 años. No intentamos determinar el valor de los beneficios no comerciables de la protección; por lo tanto, es probable que nuestros resultados subestimen los beneficios totales de la prevención de invasiones. Nuestros resultados demuestran que, aunque se disponga de pocos datos del inicio de una invasión, esos datos pueden ser suficientes para fundamentar acciones de manejo efectivas y económicamente racionales. Adicionalmente, nuestros resultados muestran que las predicciones ecológicas se están volviendo tan precisas que su aplicación en el manejo puede producir beneficios económicos netos. [source] Refining Biodiversity Conservation PrioritiesCONSERVATION BIOLOGY, Issue 6 2005GRANT M. HARRIS Bosque del Atlántico; percepción remota; priorización; SIG; sitios prioritarios para la conservación Abstract:,Although there is widespread agreement about conservation priorities at large scales (i.e., biodiversity hotspots), their boundaries remain too coarse for setting practical conservation goals. Refining hotspot conservation means identifying specific locations (individual habitat patches) of realistic size and scale for managers to protect and politicians to support. Because hotspots have lost most of their original habitat, species endemic to them rely on what remains. The issue now becomes identifying where this habitat is and these species are. We accomplished this by using straightforward remote sensing and GIS techniques, identifying specific locations in Brazil's Atlantic Forest hotspot important for bird conservation. Our method requires a regional map of current forest cover, so we explored six popular products for mapping and quantifying forest: MODIS continuous fields and a MODIS land cover (preclassified products), AVHRR, SPOT VGT, MODIS (satellite images), and a GeoCover Landsat thematic mapper mosaic (jpg). We compared subsets of these forest covers against a forest map based on a Landsat enhanced thematic mapper. The SPOT VGT forest cover predicted forest area and location well, so we combined it with elevation data to refine coarse distribution maps for forest endemic birds. Stacking these species distribution maps enabled identification of the subregion richest in threatened birds,the lowland forests of Rio de Janeiro State. We highlighted eight priority fragments, focusing on one with finer resolved imagery for detailed study. This method allows prioritization of areas for conservation from a region >1 million km2 to forest fragments of tens of square kilometers. To set priorities for biodiversity conservation, coarse biological information is sufficient. Hence, our method is attractive for tropical and biologically rich locations, where species location information is sparse. Resumen:,Aunque hay acuerdo generalizado sobre las prioridades de conservación a escalas mayores (i. e., sitios prioritarios para la conservación de la biodiversidad), los límites son muy gruesos como para definir metas de conservación prácticas. La refinación de la conservación de sitios prioritarios significa la identificación de localidades específicas (parches de hábitat individuales) de tamaño y escala realistas para ser protegidos por gestores y apoyados por políticos. Debido a que los sitios prioritarios han perdido la mayor parte de su hábitat original, las especies endémicas dependen del que permanece. Ahora el asunto es identificar donde están el hábitat y las especies. Logramos lo anterior mediante técnicas directas de percepción remota y de SIG para identificar localidades específicas importantes para la conservación de aves en el sitio prioritario Bosque del Atlántico en Brasil. Nuestro método requiere de un mapa regional de la cobertura forestal actual, así que exploramos seis productos populares para el mapeo y cuantificación de bosques: campos continuos MODIS y una cobertura de suelo MODIS (productos preclasificados), AVHRR, SPOT VGT, MODIS (imágenes de satélite) y un mosaico GeoCover Landsat thematic mapper (jpg). Comparamos subconjuntos de estas coberturas forestales con las de un mapa basado en un Landsat enhanced thematic mapper. La cobertura forestal SPOT VGT predijo bien la superficie y localización del bosque, así que lo combinamos con datos de altitud para refinar los mapas generales de distribución de aves endémicas de bosques. La sobreposición de estos mapas de distribución permitió la identificación de la subregión más rica en aves amenazadas,los bosques en bajíos del Estado de Río de Janeiro. Dimos relevancia a ocho fragmentos prioritarios, con atención en uno con imágenes de resolución fina para estudio en detalle. Este método permite la priorización de áreas para conservación de fragmentos de decenas de kilómetros cuadrados en una región >1 millón km2. La información biológica general es suficiente para definir prioridades de conservación de la biodiversidad. Por lo tanto, nuestro método es atractivo para localidades tropicales y biológicamente ricas, para las que la información sobre la ocalización de las especies es escasa. [source] An Ecological and Economic Assessment of the Nontimber Forest Product Gaharu Wood in Gunung Palung National Park, West Kalimantan, IndonesiaCONSERVATION BIOLOGY, Issue 6 2001Gary D. Paoli We studied the demographic effect and economic returns of harvesting aromatic gaharu wood from fungus-infected trees of Aquilaria malaccensis Lam. at Gunung Palung National Park, Indonesia, to evaluate the management potential of gaharu wood. Aquilaria malaccensis trees openface> 20 cm in diameter occurred at low preharvest densities (0.16,0.32 ha) but were distributed across five of six forest types surveyed. During a recent harvest, 75% of trees were felled, with harvest intensities ranging from 50% to 100% among forest types. Overall, 50% of trees contained gaharu wood, but trees at higher elevations contained gaharu wood more frequently ( 73%) than trees at lower elevation (27%). The mean density of regeneration ( juveniles> 15 cm in height) near adult trees (3,7 m away) was 0.2/m2, 200 times greater than at random in the forest (10/ha), but long-term data on growth and survivorship are needed to determine whether regeneration is sufficient for population recovery. Gaharu wood extraction from Gunung Palung was very profitable for collectors, generating an estimated gross financial return per day of US $8.80, triple the mean village wage. Yet, the estimated sustainable harvest of gaharu wood at natural tree densities generates a mean net present value of only $10.83/ha, much lower than that of commercial timber harvesting, the dominant forest use in Kalimantan. Returns per unit area could be improved substantially, however, by implementing known silvicultural methods to increase tree densities, increase the proportion of trees that produce gaharu wood, and shorten the time interval between successive harvests. The economic potential of gaharu wood is unusual among nontimber forest products and justifies experimental trials to develop small-scale cultivation methods. Resumen: Datos ecológicos y económicos son esenciales para la identificación de productos forestales no maderables tropicales con potencial para la extracción sostenible y rentable en un sistema bajo manejo. Estudiamos el efecto demográfico y los beneficios económicos de la cosecha de la madera aromática gaharu de árboles de Aquilaria malaccenis Lam infectados por hongos en el Parque Nacional Gunung Palung Indonesia para evaluar el potencial de manejo de la madera. Arboles de Aquilaria malaccenis> 20 cm de diámetro ocurrieron en bajas densidades precosecha (0.16,0.32 ha,1) pero se distribuyeron en cinco de los seis tipos de bosque muestreados. Durante una cosecha reciente, 75% de los árboles fueron cortados, con intensidades de cosecha entre 50 y 100% en los tipos de bosque. En conjunto, 50% de los árboles contenían madera gaharu, pero árboles de elevaciones mayores contenían madera gaharu más frecuentemente ( 73%) que árboles de elevaciones menores (27%). La densidad promedio de regeneración ( juveniles> 15 cm de altura) cerca de árboles adultos (de 3 a 7 m de distancia) fue de 0.2 m,2, 200 veces mayor que en el bosque (10 ha,1), pero se requieren datos a largo plazo sobre el crecimiento y la supervivencia para determinar si la regeneración es suficiente para la recuperación de la población. La extracción de madera gaharu de Gunung Palung fue muy redituable, generando un rendimiento financiero bruto estimado en US $8.80 diarios, el triple del salario promedio en la zona. Sin embargo, la cosecha sostenible estimada de madera gaharu en densidades naturales de árboles genera un valor presente neto de sólo $10.83 ha,1, mucho menor que el de la cosecha comercial de madera, uso dominante del bosque en Kalimantan. Sin embargo, los rendimientos por unidad de área podrían mejorar sustancialmente mediante la instrumentación de métodos silviculturales para incrementar la densidad de árboles, incrementar la proporción de árboles que producen madera gaharu y reducir el intervalo de tiempo entre cosechas sucesivas. El potencial económico de la madera gaharu es poco usual entre los productos forestales no maderables y justifica la experimentación para desarrollar métodos de cultivo en pequeña escala. [source] Augmentation of skin response by exposure to a combination of allergens and irritants , a reviewCONTACT DERMATITIS, Issue 5 2004Line Kynemund Pedersen Clinical experimental studies on contact dermatitis (CD) often evaluate the effect of one allergen or one irritant at a time. In real life, the skin is often exposed to more allergens, more irritants or allergens and irritants in combination. This combined exposure may potentially influence irritant effects as well as allergenicity of the substances. Mechanisms for a changed response can be immunological effects or enhanced penetration. Knowledge about the influence on skin reaction of combined exposures may influence skin reactivity and is important for prevention of CD. For allergens, threshold values may be influenced by the presence of other allergens or irritants, and prevention of CD by regulation of threshold values may not be sufficient if this is not taken into account. [source] FC03.1 Experience from joint occupational health/dermatology clinicsCONTACT DERMATITIS, Issue 3 2004Yat Wing Wong Background:, A monthly consultant led occupational health/dermatology clinic was started in 1999 providing rapid access to staff with suspected occupational skin disease including natural rubber latex (NRL) allergy and teaching for the occupational health staff. Objectives:, To evaluate the characteristics and outcome of staff attending this clinic and to assess patient satisfaction. Methods:, A retrospective case note survey was performed from staff attending the clinic from 1999 to 2002. A questionnaire was sent to them >3 months following consultation. Results:, A total of 116 patients were identified (12 male, 104 female), and 85 (73%) were nurses. 77 (66%) patients were referred with hand eczema (HE). Of the 45 patients referred with adverse reactions or exacerbation of hand dermatitis following the use of latex gloves, only 4 had positive prick tests and were considered to have NRL allergy. Patients with significant HE or occupational exacerbation of HE were referred for patch testing (n = 36). Of the remainder, most could be discharged after a single visit. 49/95 (52%) questionnaires were returned, 34/45 (76%) patients found the consultation useful. As a separate study, the data recorded within the patch test clinic looking at health care workers (HCW) referred both from this clinic and from other sources was analysed. This showed relevant positive patch tests in 16/49 (33%) patients. In 55/99 (56%), an occupational cause was likely. Conclusion:, Occupational skin disease in HCW is common, attendance at the clinic was beneficial and a single visit was sufficient in most cases. [source] Assessment of balsam of Peru patch testsCONTACT DERMATITIS, Issue 6 2000Bolli Bjarnason To find an ideal test technique for as low a dose of balsam of Peru (Myroxylon Pereirae) as possible, subjects testing positive to balsam of Peru are re-tested with a 25% concentration of balsam of Peru in petrolatum. Applications are with Finn Chambers® for 6 different application times, and directly by foils for 96 h (4 days (D)). The goals are to confirm which subjects are positive and which are not, and, using that information, to see if it is possible to distinguish between these 2 groups, tested concomitantly at much lower serial dose levels, in terms of perfusion or by visual assessments. 5 different serial doses are applied with strips for 3,96 h (4D) and with foils for 96 h (4D). The Finn Chamber® tests allow a distinction between visually positive and negative subjects supported by perfusion assessments. With the foils, a 24× lower serial dose level than with the 25% test substance is sufficient to distinguish between positive and negative subjects in terms of perfusion values. This approach requires readings up to 9 days. With this test, the visual approach yields only 3 of 10 positive subjects. This study demonstrates that a lower test dose is possible with perfusion assessments compared to visual ones. [source] Stock Price Reactions to the Repricing of Employee Stock Options,CONTEMPORARY ACCOUNTING RESEARCH, Issue 4 2005Barbara M. Grein Abstract We study whether the repricing of employee stock options is in the best interests of common shareholders by examining the excess stock returns associated with timely, noncontamin-ated repricing announcements made by Canadian firms. On the basis of three theories of why firms reprice, we develop competing predictions about the mean announcement-date excess stock return and the cross-sectional relations among excess stock returns, the estimated probability of repricing, and proxies for predictions from each theory. For a sample of 72 noncontaminated repricing announcements made by Canadian firms between November 1994 and July 2001, we find a reliably positive three-day announcement-date mean excess return of 4.9 percent. The results of our cross-sectional analyses suggest that the market responds favorably to repricings because they assist in retaining key employees even though, at the margin, they enable managers to extract rents from shareholders. We do not find sufficient statistically significant evidence to reliably conclude that repricings are done to realign employee incentives. [source] INFLATION TARGETING AND THE ECONOMY: LESSONS FROM CANADA'S FIRST DECADECONTEMPORARY ECONOMIC POLICY, Issue 1 2001C Freedman Inflation targeting has become the centerpiece of the monetary policy framework in a number of industrial countries and emerging economies. The first part of this article examines the Canadian experience with inflation targeting since its introduction in early 1991 and various issues that require resolution in establishing such a framework. It also examines the way inflation targets deal with demand, price, and productivity shocks. The second part focuses on Canada's economic performance during the 1990s. Factors other than monetary policy - most notably private sector restructuring and the fiscal situation in the first half of the decade - played an important role in the sluggishness of the recovery from the recession of 1990,91. Trend growth in Canada during the 1990s was lower than in earlier periods and than U.S. trend growth over the same period. The article examines the role of such factors as productivity growth and participation rates in explaining the differences. I conclude that a good monetary policy is necessary but not sufficient for good economic outcomes. [source] AMP-activated protein kinase in contraction regulation of skeletal muscle metabolism: necessary and/or sufficient?ACTA PHYSIOLOGICA, Issue 1 2009T. E. Jensen Abstract In skeletal muscle, the contraction-activated heterotrimeric 5,-AMP-activated protein kinase (AMPK) protein is proposed to regulate the balance between anabolic and catabolic processes by increasing substrate uptake and turnover in addition to regulating the transcription of proteins involved in mitochondrial biogenesis and other aspects of promoting an oxidative muscle phenotype. Here, the current knowledge on the expression of AMPK subunits in human quadriceps muscle and evidence from rodent studies suggesting distinct AMPK subunit expression pattern in different muscle types is reviewed. Then, the intensity and time dependence of AMPK activation in human quadriceps and rodent muscle are evaluated. Subsequently, a major part of this review critically examines the evidence supporting a necessary and/or sufficient role of AMPK in a broad spectrum of skeletal muscle contraction-relevant processes. These include glucose uptake, glycogen synthesis, post-exercise insulin sensitivity, fatty acid (FA) uptake, intramuscular triacylglyceride hydrolysis, FA oxidation, suppression of protein synthesis, proteolysis, autophagy and transcriptional regulation of genes relevant to promoting an oxidative phenotype. [source] Bureaucratization of environmental management and corporate greening: an empirical analysis of large manufacturing firms in JapanCORPORATE SOCIAL RESPONSIBILITY AND ENVIRONMENTAL MANAGEMENT, Issue 4 2005Takuya Takahashi Abstract We have used qualitative comparative analysis (QCA) to empirically investigate relationships between the organizational structure of environmental management within large Japanese manufacturing firms and their corporate greening processes. Three dimensions of bureaucratization (i.e., formalization, centralization and professionalization) were chosen as the independent variables. Measures of corporate greening, such as integration of environmental responses into general management, introduction of green technologies and transformation of corporate culture, were chosen as the dependent variables. Our sample consists of 193 firms obtained in a survey conducted in 1997. We find that bureaucratization of environmental management generally has a positive relationship with corporate greening and that the presence of one or two of the three dimensions of bureaucratization may be sufficient for corporate greening to implement certain greening measures. The relationship between bureaucratization and ISO 14001 environmental management systems (ISO 14001 EMSs) and limitations of EMSs are also discussed. Copyright © 2005 John Wiley & Sons, Ltd and ERP Environment. [source] Types and Timing of Inter,organizational Communication in New Product DevelopmentCREATIVITY AND INNOVATION MANAGEMENT, Issue 4 2001Marjan Hummel Managing the communication between the participants involved in inter,organizational product development is complex. The traditional models of new product development are not sufficient to gain insight in effective management practices in this respect. Our study explored the inter,organizational communication in a research and development project. Our results confirm Gersick's model that looks upon new product development as being punctuated by periods of rapid change. In these periods, including the start,up, explorative prototype stage, and completion of the project, inter,organizational communication is essential about design objectives and project planning, contextual factors and the required resources, skills and knowledge. [source] When is high-Ca2+ microdomain required for mitochondrial Ca2+ uptake?,ACTA PHYSIOLOGICA, Issue 1 2009A. Spät Abstract Ca2+ release from IP3 -sensitive stores in the endoplasmic reticulum (ER) induced by Ca2+ -mobilizing agonists generates high-Ca2+ microdomains between ER vesicles and neighbouring mitochondria. Here we present a model that describes when such microdomains are required and when submicromolar [Ca2+] is sufficient for mitochondrial Ca2+ uptake. Mitochondrial Ca2+ uptake rate in angiotensin II-stimulated H295R adrenocortical cells correlates with the proximity between ER vesicles and the mitochondrion, reflecting the uptake promoting effect of high-Ca2+ peri-mitochondrial microdomains. Silencing or inhibition of p38 mitogen-activated protein kinase (MAPK) or inhibition of the novel isoforms of protein kinase C enhances mitochondrial Ca2+ uptake and abolishes the positive correlation between Ca2+ uptake and ER-mitochondrion proximity. Inhibition of protein phosphatases attenuates mitochondrial Ca2+ uptake and also abolishes its positive correlation with ER-mitochondrion proximity. We postulate that during IP3 -induced Ca2+ release, Ca2+ uptake is confined to ER-close mitochondria, because of the simultaneous activation of the protein kinases. Attenuation of Ca2+ uptake prevents Ca2+ overload of mitochondria and thus protects the cell against apoptosis. On the other hand, all the mitochondria accumulate Ca2+ at a non-inhibited rate during physiological Ca2+ influx through the plasma membrane. Membrane potential is higher in ER-distant mitochondria, providing a bigger driving force for Ca2+ uptake. Our model explains why comparable mitochondrial Ca2+ signals are formed in response to K+ and angiotensin II (equipotent in respect to global cytosolic Ca2+ signals), although only the latter generates high-Ca2+ microdomains. [source] Thermal and EPR investigations of thallium gallium disulphide single crystalCRYSTAL RESEARCH AND TECHNOLOGY, Issue 7 2009M. Acikgoz Abstract In this research, the results of the differential scanning calorimetry (DSC) and electron paramagnetic resonance (EPR) investigations of TlGaS2 single crystal are presented. Specific heat capacity (Cp) anomalies of layered TlGaS2 have been obtained by using a new DSC technique for such crystals. Remarkable heat capacity anomalies have been revealed at the temperatures of 137.7 K, 174.5 K and 238.5 K. It is found that the anomalies appear at maximum with a small deviation (by 3-4%) from the regular values, and Cp discontinuity amounted to approximately 5%. Additionally, EPR spectra of Fe doped TlGaS2 single crystals have been recorded at various temperatures down to 6 K for different orientations of the applied magnetic field. Transformations of present EPR spectra are not sufficient for the confirmation of structural phase transitions, in contrast to the cases in iso structural TlInS2 and TlGaSe2 compounds. (© 2009 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) [source] The BSCC Code of Practice , exfoliative cytopathology (excluding gynaecological cytopathology)CYTOPATHOLOGY, Issue 4 2009A. Chandra Exfoliative cytopathology (often referred to as non-gynaecological cytology) is an important part of the workload of all diagnostic pathology departments. It clearly has a role in the diagnosis of neoplastic disease but its role in establishing non-neoplastic diagnoses should also be recognised. Ancillary tests may be required to establish a definitive diagnosis. Clinical and scientific teamwork is essential to establish an effective cytology service and staffing levels should be sufficient to support preparation, prescreening, on-site adequacy assessment and reporting of samples as appropriate. Routine clinical audit and histology/cytology correlation should be in place as quality control of a cytology service. Cytology staff should be involved in multidisciplinary meetings and appropriate professional networks. Laboratories should have an effective quality management system conforming to the requirements of a recognised accreditation scheme such as Clinical Pathology Accreditation (UK) Ltd. Consultant pathologists should sign out the majority of exfoliative cytology cases. Where specimens are reported by experienced biomedical scientists (BMS), referred to as cytotechnologists outside the UK, this must only be when adequate training has been given and be defined in agreed written local protocols. An educational basis for formalising the role of the BMS in exfoliative cytopathology is provided by the Diploma of Expert Practice in Non-gynaecological Cytology offered by the Institute of Biomedical Science (IBMS). The reliability of cytological diagnoses is dependent on the quality of the specimen provided and the quality of the preparations produced. The laboratory should provide feedback and written guidance on specimen procurement. Specimen processing should be by appropriately trained, competent staff with appropriate quality control. Microscopic examination of preparations by BMS should be encouraged wherever possible. Specific guidance is provided on the clinical role, specimen procurement, preparation and suitable staining techniques for urine, sputum, semen, serous cavity effusion, cerebrospinal fluid, synovial fluid, cyst aspirates, endoscopic specimens, and skin and mucosal scrapes. [source] The translocation of signaling molecules in dark adapting mammalian rod photoreceptor cells is dependent on the cytoskeletonCYTOSKELETON, Issue 10 2008Boris Reidel Abstract In vertebrate rod photoreceptor cells, arrestin and the visual G-protein transducin move between the inner segment and outer segment in response to changes in light. This stimulus dependent translocation of signalling molecules is assumed to participate in long term light adaptation of photoreceptors. So far the cellular basis for the transport mechanisms underlying these intracellular movements remains largely elusive. Here we investigated the dependency of these movements on actin filaments and the microtubule cytoskeleton of photoreceptor cells. Co-cultures of mouse retina and retinal pigment epithelium were incubated with drugs stabilizing and destabilizing the cytoskeleton. The actin and microtubule cytoskeleton and the light dependent distribution of signaling molecules were subsequently analyzed by light and electron microscopy. The application of cytoskeletal drugs differentially affected the cytoskeleton in photoreceptor compartments. During dark adaptation the depolymerization of microtubules as well as actin filaments disrupted the translocation of arrestin and transducin in rod photoreceptor cells. During light adaptation only the delivery of arrestin within the outer segment was impaired after destabilization of microtubules. Movements of transducin and arrestin required intact cytoskeletal elements in dark adapting cells. However, diffusion might be sufficient for the fast molecular movements observed as cells adapt to light. These findings indicate that different molecular translocation mechanisms are responsible for the dark and light associated translocations of arrestin and transducin in rod photoreceptor cells. Cell Motil. Cytoskeleton 65: 785,800, 2008. © 2008 Wiley-Liss, Inc. [source] Myosin16b: The COOH-tail region directs localization to the nucleus and overexpression delays S-phase progressionCYTOSKELETON, Issue 1 2007Richard S. Cameron Abstract Rat Myo16a and Myo16b comprise the founding members of class XVI myosin and are characterized by an N-terminal ankyrin repeat domain thought to mediate an association with protein phosphatase 1 catalytic subunits 1, and 1,. Myo16b is the principal isoform and reveals predominant expression in developing neural tissue. Here, we use COS-7 cells as a model system to develop an understanding of Myo16b function. We find that Myo16b displays predominant localization in the nucleus of cells transitioning through interphase, but is not associated with processes of mitosis. Using a panel of EGFP-Myo16b-expression plasmids in transient transfection studies, we identified the COOH-terminal residues 1616,1912 as necessary and solely sufficient to target Myo16b to the nucleus. We show that the Myo16b-tail region directs localization to a nuclear compartment containing profilin and polymerized actin, which appears to form a three-dimensional meshwork through the depth of the nucleus. Further, we demonstrate that this compartment localizes within euchromatic regions of the genome and contains proliferating cell nuclear antigen (PCNA) and cyclin A, both markers of S-phase of the cell cycle. Cells transiently expressing Myo16b or Myo16b-tail region show limited incorporation of BrdU, delayed progression through S-phase of the cell cycle, and curtailed cellular proliferation. Cell Motil. Cytoskeleton 2006. © 2006 Wiley-Liss, Inc. [source] Effects of substrate stiffness on cell morphology, cytoskeletal structure, and adhesionCYTOSKELETON, Issue 1 2005Tony Yeung Abstract The morphology and cytoskeletal structure of fibroblasts, endothelial cells, and neutrophils are documented for cells cultured on surfaces with stiffness ranging from 2 to 55,000 Pa that have been laminated with fibronectin or collagen as adhesive ligand. When grown in sparse culture with no cell-cell contacts, fibroblasts and endothelial cells show an abrupt change in spread area that occurs at a stiffness range around 3,000 Pa. No actin stress fibers are seen in fibroblasts on soft surfaces, and the appearance of stress fibers is abrupt and complete at a stiffness range coincident with that at which they spread. Upregulation of ,5 integrin also occurs in the same stiffness range, but exogenous expression of ,5 integrin is not sufficient to cause cell spreading on soft surfaces. Neutrophils, in contrast, show no dependence of either resting shape or ability to spread after activation when cultured on surfaces as soft as 2 Pa compared to glass. The shape and cytoskeletal differences evident in single cells on soft compared to hard substrates are eliminated when fibroblasts or endothelial cells make cell-cell contact. These results support the hypothesis that mechanical factors impact different cell types in fundamentally different ways, and can trigger specific changes similar to those stimulated by soluble ligands. Cell Motil. Cytoskeleton 60:24,34, 2005. © 2004 Wiley-Liss, Inc. [source] Expression of constructs of the neuronal isoform of myosin-Va interferes with the distribution of melanosomes and other vesicles in melanoma cellsCYTOSKELETON, Issue 2 2002João Carlos da Silva Bizario Abstract Myosin-Va has been implicated in melanosome translocation, but the exact molecular mechanisms underlying this function are not known. In the dilute, S91 melanoma cells, melanosomes move to the cell periphery but do not accumulate in the tips of dendrites as occurs in wild-type B16 melanocytes; rather, they return and accumulate primarily at the pericentrosomal region in a microtubule-dependent manner. Expression of the full-length neuronal isoform of myosin-Va in S91 cells causes melanosomes to disperse, occupying a cellular area approximately twice that observed in non-transfected cells, suggesting a partial rescue of the dilute phenotype. Overexpression of the full tail domain in S91 cells is not sufficient to induce melanosome dispersion, rather it causes melanosomal clumping. Overexpression of the head and head-neck domains of myosin-Va in B16 cells does not alter the melanosome distribution. However, overexpression of the full tail domain in these cells induces melanosome aggregation and the appearance of tail-associated, aggregated particles or vesicular structures that exhibit variable degrees of staining for melanosomal and Golgi ,-COP markers, as well as colocalization with the endogenous myosin-Va. Altogether, the present data suggest that myosin-Va plays a role in regulating the direction of microtubule-dependent melanosome translocation, in addition to promoting the capture of melanosomes at the cell periphery as suggested by previous studies. These studies also reinforce the notion that myosin-V has a broader function in melanocytes by acting on vesicular targeting or intracellular protein trafficking. Cell Motil. Cytoskeleton 51:57,75, 2002. © 2002 Wiley-Liss, Inc. [source] No effect of venoconstrictive thigh cuffs on orthostatic hypotension induced by head-down bed restACTA PHYSIOLOGICA, Issue 2 2000M.-A. Custaud Orthostatic intolerance (OI) is the most serious symptom of cardiovascular deconditioning induced by head-down bed rest or weightlessness. Wearing venoconstrictive thigh cuffs is an empirical countermeasure used by Russian cosmonauts to limit the shift of fluid from the lower part of the body to the cardio-cephalic region. Our aim was to determine whether or not thigh cuffs help to prevent orthostatic hypotension induced by head-down bed rest. We studied the effect of thigh cuffs on eight healthy men. The cuffs were worn during the day for 7 days of head-down bed rest. We measured: orthostatic tolerance (stand tests and lower body negative pressure tests), plasma volume (Evans blue dilution), autonomic influences (plasma noradrenaline) and baroreflex sensitivity (spontaneous baroreflex slope). Thigh cuffs limited the loss of plasma volume (thigh cuffs: ,201 ± 37 mL vs. control: ,345 ± 42 mL, P < 0.05), the degree of tachycardia and reduction in the spontaneous baroreflex sensitivity induced by head-down bed rest. However, the impact of thigh cuffs was not sufficient to prevent OI (thigh cuffs: 7.0 min of standing time vs. control: 7.1 min). Decrease in absolute plasma volume and in baroreflex sensitivity are known to be important factors in the aetiology of OI induced by head-down bed rest. However, dealing with these factors, using thigh cuffs for example, is not sufficient to prevent OI. Other factors such as venous compliance, microcirculatory changes, peripheral arterial vasoconstriction and vestibular afferents must also be considered. [source] | ||||||||||||||||||||||||||||||||||