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Apparent
Kinds of Apparent Terms modified by Apparent Selected AbstractsWavelet Transforms for System Identification in Civil EngineeringCOMPUTER-AIDED CIVIL AND INFRASTRUCTURE ENGINEERING, Issue 5 2003T. Kijewski Although challenges did not surface in prior applications concerned with mechanical systems, which are characterized by higher frequency and broader-band signals, the transition to the time-frequency domain for the analysis of civil engineering structures highlighted the need to understand more fully various processing concerns, particularly for the popular Morlet wavelet. In particular, as these systems may possess longer period motions and thus require finer frequency resolutions, the particular impacts of end effects become increasingly apparent. This study discusses these considerations in the context of the wavelet's multi-resolution character and includes guidelines for selection of wavelet central frequencies, highlights their role in complete modal separation, and quantifies their contributions to end-effect errors, which may be minimized through a simple padding scheme. [source] Alignment and structural analysis of membrane polypeptides by 15N and 31P solid-state NMR spectroscopyCONCEPTS IN MAGNETIC RESONANCE, Issue 2 2003Burkhard Bechinger Abstract In contrast to solution NMR spectroscopy, where complete or almost complete averaging leads to isotropic values, the anisotropic character of nuclear interactions is apparent in solid-state NMR spectra. The orientation dependence of chemical shift and dipolar or quadrupolar interactions has been used to obtain dynamic as well as angular information from polypeptides that strongly interact with phospholipid bilayers. This article illustrates the advantageous characteristics of the anisotropic 15N or 31P chemical shift interactions that in a direct manner allow one to obtain information on the alignment of helical polypeptides or of phospholipid head groups with respect to the membrane normal. © 2003 Wiley Periodicals, Inc. Concepts Magn Reson 18A: 130,145, 2003 [source] Differences in sino-atrial and atrio-ventricular function with age and sex attributable to the Scn5a+/, mutation in a murine cardiac modelACTA PHYSIOLOGICA, Issue 1 2010K. Jeevaratnam Abstract Aim:, To investigate the interacting effects of age and sex on electrocardiographic (ECG) features of Scn5a+/, mice modelling Brugada syndrome. Methods:, Recordings were performed on anaesthetized wild-type (WT) and Scn5a+/, mice and differences attributable to these risk factors statistically stratified. Results:,Scn5a+/, exerted sex-dependent effects upon sino-atrial function that only became apparent with age. RR intervals were greater in old male than in old female Scn5a+/,. Atrio-ventricular (AV) conduction was slower in young female mice, whether WT and Scn5a+/,, than the corresponding young male WT and Scn5a+/,. However, PR intervals lengthened with age in male but not in female Scn5a+/, giving the greatest PR intervals in old male Scn5a+/, compared with either old male WT or young male Scn5a+/, mice. In contrast, PR intervals were similar in old female Scn5a+/, and in old female WT. QTc was prolonged in Scn5a+/, compared with WT, and female Scn5a+/, compared with female WT. Age-dependent alterations in durations of ventricular repolarization relative to WT affected male but not female Scn5a+/,. Thus, T-wave durations were greater in old male Scn5a+/, compared with old male WT, but indistinguishable between old female Scn5a+/, and old female WT. Finally, analysis for combined interactions of genotype, age and sex demonstrated no effects on P wave and QRS durations and QTc intervals. Conclusion:, We demonstrate for the first time that age, sex and genotype exert both independent and interacting ECG effects. The latter suggest alterations in cardiac pacemaker function, atrio-ventricular conduction and ventricular repolarization greatest in ageing male Scn5a+/,. [source] Congenital polymicrogyria including the perisylvian region in early childhoodCONGENITAL ANOMALIES, Issue 1 2010Tomoyuki Takano ABSTRACT Six pediatric cases including four infants with congenital polymicrogyria including the perisylvian region are presented herein. Their clinical features were analyzed and compared with patients suffering from congenital bilateral perisylvian syndrome (CBPS). Two specific abnormalities were diagnosed as accompanying disorders in two cases, namely Kabuki syndrome and Peters' anomaly. In the other four cases, the pathogenetic etiology was not elucidated. Subtle symptoms, such as choking and drooling became detectable in one case each, and expressive language development was delayed in two patients. A developmental delay became apparent in five cases during the follow-up period, and epilepsy was observed in one patient with onset at 12 years of age. Our results indicate that the presence of perisylvian polymicrogyria may not always result in the development of oropharyngoglossal dysfunction or dysarthria, although most patients tend to gradually show the onset of developmental disorders. To support cognitive and psychosocial development, an early integrated approach, including not only conventional speech and language therapy, but also various communication methods is essential for patients with congenital polymicrogyria including the perisylvian region. [source] Neurodevelopmental Outcomes in Infants after Surgery for Congenital Heart Disease: A Comparison of Single-Ventricle vs.CONGENITAL HEART DISEASE, Issue 2 2010Two-Ventricle Physiology ABSTRACT Introduction., The neurodevelopmental outcome of children with repaired congenital heart defect has risen in importance with improved survival. This study compares neurodevelopmental outcomes of children who had CHD with single ventricle physiology with those who had CHD with two-ventricle physiology. Patients and Methods., Participants included 112 infants discharged from the NICU between February 1999 to August 2006. The 12 infants who had a known genetic defect were excluded. Of the 100 infants 26 had single ventricle physiology and 74 had CHD with two-ventricle physiology. The children were seen in a follow-up clinic and growth parameters and standardized instruments were used to evaluate development. The referral rate to early intervention services was also compared. Results., The number of functional ventricles did not significantly differentiate growth parameters at 6,8 months of age. Early cognitive outcomes were relatively unimpaired in both the groups (single ventricle vs. two ventricle physiology). Early motor outcomes were worse in (p < 0.05) CHD with single ventricle physiology. The rate of referral for early intervention services was high in both groups compared to the average rate of referral in the state, but there was not a significant difference between the CHD groups. Conclusion., Significant differences noted on motor outcomes at the 6,8 month visit were no longer apparent in later visits. Referral to early intervention services is high in both the groups. These findings are important to those caring for infants with CHD because many of these patients may need referral for early intervention. [source] Increased Mortality Associated With Low Use of Clopidogrel in Patients With Heart Failure and Acute Myocardial Infarction Not Undergoing Percutaneous Coronary InterventionCONGESTIVE HEART FAILURE, Issue 5 2010Scott Harris DO We studied the association of clopidogrel with mortality in acute myocardial infarction (AMI) patients with heart failure (HF) not receiving percutaneous coronary intervention (PCI). Background. Use of clopidogrel after AMI is low in patients with HF, despite the fact that clopidogrel is associated with absolute mortality reduction in AMI patients. Methods. All patients hospitalized with first-time AMI (2000 through 2005) and not undergoing PCI within 30 days from discharge were identified in national registers. Patients with HF treated with clopidogrel were matched by propensity score with patients not treated with clopidogrel. Similarly, 2 groups without HF were identified. Risks of all-cause death were obtained by the Kaplan,Meier method and Cox regression analyses. Results. We identified 56,944 patients with first-time AMI. In the matched cohort with HF (n=5050) and a mean follow-up of 1.50 years (SD=1.2), 709 (28.1%) and 812 (32.2%) deaths occurred in patients receiving and not receiving clopidogrel treatment, respectively (P=.002). The corresponding numbers for patients without HF (n=6092), with a mean follow-up of 2.05 years (SD=1.3), were 285 (9.4%) and 294 (9.7%), respectively (P=.83). Patients with HF receiving clopidogrel demonstrated reduced mortality (hazard ratio, 0.86; 95% confidence interval, 0.78,0.95) compared with patients with HF not receiving clopidogrel. No difference was observed among patients without HF (hazard ratio, 0.98; 95% confidence interval, 0.83,1.16). Conclusions. Clopidogrel was associated with reduced mortality in patients with HF who do not undergo PCI after their first-time AMI, whereas this association was not apparent in patients without HF. Further studies of the benefit of clopidogrel in patients with HF and AMI are warranted.,Bonde L, Sorensen R, Fosbol EL, et al. Increased mortality associated with low use of clopidogrel in patients with heart failure and acute myocardial infarction not undergoing percutaneous coronary intervention: a nationwide study. J Am Coll Cardiol. 2010;55:1300,1307. [source] Pacific Salmon Extinctions: Quantifying Lost and Remaining DiversityCONSERVATION BIOLOGY, Issue 4 2007RICHARD G. GUSTAFSON biodiversidad; diversidad de salmones; extinción de poblaciones; historia de vida de salmones Abstract:,Widespread population extirpations and the consequent loss of ecological, genetic, and life-history diversity can lead to extinction of evolutionarily significant units (ESUs) and species. We attempted to systematically enumerate extinct Pacific salmon populations and characterize lost ecological, life history, and genetic diversity types among six species of Pacific salmon (Chinook [Oncorhynchus tshawytscha], sockeye [O. nerka], coho [O. kisutch], chum [O. keta], and pink salmon [O. gorbuscha] and steelhead trout [O. mykiss]) from the western contiguous United States. We estimated that, collectively, 29% of nearly 1400 historical populations of these six species have been lost from the Pacific Northwest and California since Euro-American contact. Across all species there was a highly significant difference in the proportion of population extinctions between coastal (0.14 extinct) and interior (0.55 extinct) regions. Sockeye salmon (which typically rely on lacustrine habitats for rearing) and stream-maturing Chinook salmon (which stay in freshwater for many months prior to spawning) had significantly higher proportional population losses than other species and maturation types. Aggregate losses of major ecological, life-history, and genetic biodiversity components across all species were estimated at 33%, 15%, and 27%, respectively. Collectively, we believe these population extirpations represent a loss of between 16% and 30% of all historical ESUs in the study area. On the other hand, over two-thirds of historical Pacific salmon populations in this area persist, and considerable diversity remains at all scales. Because over one-third of the remaining populations belong to threatened or endangered species listed under the U.S. Endangered Species Act, it is apparent that a critical juncture has been reached in efforts to preserve what remains of Pacific salmon diversity. It is also evident that persistence of existing, and evolution of future, diversity will depend on the ability of Pacific salmon to adapt to anthropogenically altered habitats. Resumen:,Las extirpaciones generalizadas de poblaciones y la consecuente pérdida de diversidad ecológica, genética y de historia natural puede llevar a la extinción de unidades evolutivamente significativas (UES) y especies. Intentamos enumerar sistemáticamente a las poblaciones extintas de salmón del Pacífico y caracterizar a los tipos de diversidad ecológica, de historia natural y genética de seis especies de salmón del Pacífico Oncorhynchus tshawytscha, O. nerka, O. kisutch, O. keta, y O. gorbuscha; y trucha O. mykiss en el occidente de Estados Unidos. Estimamos que, colectivamente, se ha perdido a 29% de casi 1400 poblaciones históricas de estas seis especies en el Pacífico Noroeste y California desde la colonización europea. En todas las especies hubo una diferencia altamente significativa en la proporción de extinción de poblaciones entre regiones costeras (0.14 extintas) e interiores (0.55 extintas). O. nerka (que típicamente cría en hábitats lacustres) y O. tshawytscha (que permanece en agua dulce por muchos meses antes del desove) tuvieron pérdidas poblacionales significativamente mayores que las otras especies y tipos de maduración. Se estimó que las pérdidas agregadas de componentes mayores de la biodiversidad ecológica, de historia natural y genética en todas las especies fueron de 33%, 15% y 27%, respectivamente. Colectivamente, consideramos que estas extirpaciones de poblaciones representan una pérdida entre 16% y 30% de todas las UES históricas en el área de estudio. Por otro lado, más de dos tercios de las poblaciones históricas de salmón del Pacífico persisten en esta área, y aun hay considerable diversidad en todas las escalas. Debido a que más de un tercio de las poblaciones restantes pertenecen a especies enlistadas como amenazadas o en peligro en el Acta de Especies en Peligro de E. U. A., es evidente que se ha llegado a una disyuntiva crítica en los esfuerzos para preservar lo que queda de la diversidad de salmón del Pacífico. También es evidente que la persistencia de la diversidad existente, y su futura evolución, dependerá de la habilidad del salmón del Pacífico para adaptarse a hábitats alterados antropogénicamente. [source] Potential of Marine Reserves to Cause Community-Wide Changes beyond Their BoundariesCONSERVATION BIOLOGY, Issue 2 2007PAOLO GUIDETTI arrecifes rocosos templados; cambios a nivel comunitario; cascadas tróficas; estados comunitarios alternativos; exceso de pesca; reservas marinas Abstract:,Fishing and other human activities can alter the abundances, size structure, and behavior of species playing key roles in shaping marine communities (e.g., keystone predators), which may in turn cause ecosystem shifts. Despite extensive evidence that cascading trophic interactions can underlie community-wide recovery inside no-take marine reserves by protecting high-level predators, the spatial extent of these effects into adjacent fished areas is unknown. I examined the potential for community-wide changes (i.e., the transition from overgrazed coralline barrens to macroalgal beds) in temperate rocky reefs within and around a no-take marine reserve. For this purpose I assessed distribution patterns of predatory fishes, sea urchins, and barrens across the reserve boundaries. Predatory fishes were significantly more abundant within the reserve than in adjacent locations, with moderate spillover across the reserve edges. In contrast, community-wide changes of benthic assemblages were apparent well beyond the reserve boundaries, which is consistent with temporary movements of predatory fishes (e.g., foraging migration) from the reserve to surrounding areas. My results suggest that no-take marine reserves can promote community-wide changes beyond their boundaries. Resumen:,La pesca y otras actividades humanas pueden alterar la abundancia, tamaño, estructura y comportamiento de las especies que juegan papeles clave en el modelado de las comunidades marinas (e.g., depredadores clave), que a su vez pueden causar cambios en los ecosistemas. No obstante la evidencia extensiva de que las interacciones tróficas en cascada pueden subyacer en la recuperación de la comunidad dentro de reservas marinas que no permiten la pesca mediante la protección de depredadores de nivel alto, se desconoce la extensión espacial de estos efectos en áreas adyacentes. Examiné el potencial de los cambios a nivel comunidad (i.e., la transición de áreas coralinas sobre pastoreadas a lechos de microalgas) en arrecifes rocosos templados dentro y alrededor de una reserva marina sin pesca. Para este propósito, evalué los patrones de distribución de peces depredadores, erizos de mar y áreas sobre pastoreadas en los límites de la reserva. Los peces depredadores fueron significativamente más abundantes dentro de la reserva que en localidades adyacentes, con un excedente moderado en los bordes de la reserva. En contraste, los cambios a nivel de comunidad en los ensambles bénticos fueron aparentes más allá de los límites de la reserva, lo que es consistente con los movimientos temporales de los peces depredadores (e.g., migración de forrajeo) desde la reserva hacia las áreas circundantes. Mis resultados sugieren que las reservas que no permiten la pesca pueden promover cambios a nivel comunidad más allá de sus límites. [source] Detecting the Effects of Fishing on Seabed Community Diversity: Importance of Scale and Sample SizeCONSERVATION BIOLOGY, Issue 2 2003Michel J. Kaiser I investigated the importance of the extent of area sampled to the observed outcome of comparisons of the diversity of seabed assemblages in different areas of the seabed that experience either low or high levels of fishing disturbance. Using a finite data set within each disturbance regime, I pooled samples of the benthic communities at random. Thus, although individual sample size increased with each additional level of pooled data, the number of samples decreased accordingly. Detecting the effects of disturbance on species diversity was strongly scale-dependent. Despite increased replication at smaller scales, disturbance effects were more apparent when larger but less numerous samples were collected. The detection of disturbance effects was also affected by the choice of sampling device. Disturbance effects were apparent with pooled anchor-dredge samples but were not apparent with pooled beam-trawl samples. A more detailed examination of the beam-trawl data emphasized that a whole-community approach to the investigation of changes in diversity can miss responses in particular components of the community ( e.g., decapod crustacea ). The latter may be more adversely affected by disturbance than the majority of the taxa found within the benthic assemblage. Further, the diversity of some groups ( e.g., echinoderms ) actually increased with disturbance. Experimental designs and sampling regimes that focus on diversity at only one scale may miss important disturbance effects that occur at larger or smaller scales. Resumen: Las perturbaciones antropogénicas de ambientes terrestres y marinos, tales como la tala y la pesca, se identifican generalmente con impactos negativos sobre la diversidad de especies. Sin embargo, observaciones empíricas a menudo no apoyan este supuesto. Investigué la importancia de la extensión del área muestreada sobre los resultados observados de comparaciones de la diversidad de ensamblajes de fondos marinos en diferentes áreas que experimentaron niveles bajos o altos de perturbación por pesca. Usando un juego finito de datos dentro de cada régimen de perturbación, se combinaron las muestras de comunidades bénticas de manera aleatoria. Por lo tanto, a pesar de que el tamaño de muestra individual incrementó con cada nivel adicional de datos combinados, el número de muestras disminuyó en consecuencia. La detección de los efectos de la perturbación sobre la diversidad de especies dependió en gran medida de la escala. A pesar del incremento en replicación de las escalas pequeñas, los efectos de la perturbación fueron más visibles cuando las muestras recolectadas fueron más grandes pero menos numerosas. La detección de los efectos de la perturbación también fueron afectados por la selección del equipo de muestreo. Los efectos de la perturbación eran evidentes cuando se usaron muestras mezcladas de dragas de ancla, pero no fueron evidentes para muestras mezcladas de redes de arrastre con vigas. Un análisis más detallado de los datos de las redes de arrastre muestran que una aproximación a nivel de toda la comunidad para investigar los cambios de diversidad puede resultar en la pérdida de información a nivel de componentes específicos ( por ejemplo crustáceos decápodos ) de la comunidad. Estos pueden ser adversamente afectados en mayor medida por la perturbación que la mayoría de los taxones que integran el ensamblaje béntico. Además, la diversidad de algunos grupos ( por ejemplo los equinodermos ) de hecho aumentó con la perturbación. Los diseños experimentales y los regímenes de muestreo que se enfocan en la diversidad a una sola escala pueden no detectar los efectos importantes de la perturbación que ocurren a mayores o menores escalas. [source] Habitat Loss and Extinction in the Hotspots of BiodiversityCONSERVATION BIOLOGY, Issue 4 2002Thomas M. Brooks None of these hotspots have more than one-third of their pristine habitat remaining. Historically, they covered 12% of the land's surface, but today their intact habitat covers only 1.4% of the land. As a result of this habitat loss, we expect many of the hotspot endemics to have either become extinct or,because much of the habitat loss is recent,to be threatened with extinction. We used World Conservation Union [ IUCN ] Red Lists to test this expectation. Overall, between one-half and two-thirds of all threatened plants and 57% of all threatened terrestrial vertebrates are hotspot endemics. For birds and mammals, in general, predictions of extinction in the hotspots based on habitat loss match numbers of species independently judged extinct or threatened. In two classes of hotspots the match is not as close. On oceanic islands, habitat loss underestimates extinction because introduced species have driven extinctions beyond those caused by habitat loss on these islands. In large hotspots, conversely, habitat loss overestimates extinction, suggesting scale dependence (this effect is also apparent for plants). For reptiles, amphibians, and plants, many fewer hotspot endemics are considered threatened or extinct than we would expect based on habitat loss. This mismatch is small in temperate hotspots, however, suggesting that many threatened endemic species in the poorly known tropical hotspots have yet to be included on the IUCN Red Lists. We then asked in which hotspots the consequences of further habitat loss (either absolute or given current rates of deforestation) would be most serious. Our results suggest that the Eastern Arc and Coastal Forests of Tanzania-Kenya, Philippines, and Polynesia-Micronesia can least afford to lose more habitat and that, if current deforestation rates continue, the Caribbean, Tropical Andes, Philippines, Mesoamerica, Sundaland, Indo-Burma, Madagascar, and Chocó,Darién,Western Ecuador will lose the most species in the near future. Without urgent conservation intervention, we face mass extinctions in the hotspots. Resumen: Casi la mitad del total de plantas vasculares del mundo y un tercio de los vertebrados terrestres son endémicos en 25 "áreas críticas" para la biodiversidad, cada una de las cuales tiene por lo menos 1500 especies de plantas endémicas. En ninguno de estos sitios permanece más de un tercio de su hábitat prístino. Históricamente, cubrían 12% de la superficie terrestre, pero en la actualidad su hábitat intacto cubre solo 1.4% del terreno. Como resultado de esta pérdida de hábitat esperamos que muchas de las especies endémicas a estos sitios estén extintas o , porque la pérdida de hábitat es reciente , se encuentren amenazadas de extinción. Utilizamos Listas Rojas de UICN para comprobar esta predicción. En general, entre la mitad y dos tercios de las plantas amenazadas y el 57% de los vertebrados terrestres amenazados son endémicos de áreas críticas para la biodiversidad. Para aves y mamíferos en general, las predicciones de extinción en las áreas críticas para la biodiversidad, basadas en la pérdida de hábitat, coinciden con el número de especies consideradas extintas o amenazadas independientemente. En dos clases de áreas críticas para la biodiversidad la coincidencia no es muy grande. En islas oceánicas, la pérdida de hábitat subestima la extinción porque las especies introducidas han causado más extinciones que las producidas por la reducción del hábitat. Por lo contrario, la pérdida de hábitat sobrestima la extinción en áreas críticas para la biodiversidad extensas, lo que sugiere una dependencia de escala (este efecto también es aparente para plantas). Para reptiles, anfibios y plantas mucho menos especies endémicas son consideradas amenazadas o extintas por pérdida de hábitat. Sin embargo, esta discordancia es pequeña en áreas críticas para la biodiversidad en zonas templadas templadas, lo que sugiere que muchas especies endémicas amenazadas en las poco conocidas áreas críticas para la biodiversidad en zonas tropicales aun están por incluirse en las Listas Rojas. Posteriormente nos preguntamos en que áreas críticas para la biodiversidad serían más serias las consecuencias de una mayor pérdida de hábitat (absoluta o con las tasas actuales de deforestación). Nuestros resultados sugieren que el Arco Oriental y los Bosques Costeros de Tanzania/Kenia, Filipinas, Polinesia/Micronesia no pueden soportar mayores pérdidas y que, si continúan las tasas de deforestación actuales, el Caribe, Andes Tropicales, Filipinas, Mesoamérica, Sundaland, Indo-Burma, Madagascar y Chocó/Darién/Ecuador Occidental perderán más especies en el futuro. Sin acciones urgentes de conservación, habrá extinciones masivas en las áreas críticas para la biodiversidad. [source] Stroke volume decreases during mild dynamic and static exercise in supine humansACTA PHYSIOLOGICA, Issue 2 2009M. Elstad Abstract Aim:, The contributions of cardiac output (CO) and total peripheral resistance to changes in arterial blood pressure are debated and differ between dynamic and static exercise. We studied the role stroke volume (SV) has in mild supine exercise. Methods:, We investigated 10 healthy, supine volunteers by continuous measurement of heart rate (HR), mean arterial blood pressure, SV (ultrasound Doppler) and femoral beat volume (ultrasound Doppler) during both dynamic mild leg exercise and static forearm exercise. This made it possible to study CO, femoral flow (FF) and both total and femoral peripheral resistance beat-by-beat. Results:, During a countdown period immediately prior to exercise, HR and mean arterial pressure increased, while SV decreased. During mild supine exercise, SV decreased by 5,8%, and most of this was explained by increased mean arterial pressure. Dynamic leg exercise doubled femoral beat volume, while static hand grip decreased femoral beat volume by 18%. FF is tightly regulated according to metabolic demand during both dynamic leg exercise and static forearm exercise. Conclusion:, Our three major findings are, firstly, that SV decreases during both dynamic and static mild supine exercise due to an increase in mean arterial pressure. Secondly, femoral beat volume decreases during static hand grip, but FF is unchanged due to the increase in HR. Finally, anticipatory responses to exercise are apparent prior to both dynamic and static exercise. SV changes contribute to CO changes and should be included in studies of central haemodynamics during exercise. [source] Aggressive behaviour and social problem-solving strategies: a review of the findings of a seven-year follow-up from childhood to late adolescenceCRIMINAL BEHAVIOUR AND MENTAL HEALTH, Issue 4 2001Liisa Keltikangas-Järvinen PhD Professor Objectives In a seven-year follow-up study, the author and colleagues examined the development of social skills from childhood to late adolescence, with a particular focus on aggressive behaviour. This paper presents a review of the most important findings of the project. Results and conclusions Social strategies explained aggressive behaviour, and changes of strategies predicted changes of behaviour. Aggressive behaviour was, however, very stable, and spontaneous change from an aggressive child to a sociable adolescent was not observed. This emphasizes an importance of early prevention of aggression. Disagreement between the children's and their parents' problem-solving strategies was apparent, suggesting that interventions to reduce a child's aggression should be augmented by educating the parents about their children's behaviour. The role of peers was important because the child's concept of his or her strategies was dependent on his or her social acceptance, and this should be taken into account in interventions. Finally, as approval or disapproval of aggression is related to behaviour, moral cognitions should be included in the interventions. Copyright © 2001 Whurr Publishers Ltd. [source] ESTIMATING A DOSE-RESPONSE RELATIONSHIP BETWEEN LENGTH OF STAY AND FUTURE RECIDIVISM IN SERIOUS JUVENILE OFFENDERS,CRIMINOLOGY, Issue 3 2009THOMAS A. LOUGHRAN The effect of sanctions on subsequent criminal activity is of central theoretical importance in criminology. A key question for juvenile justice policy is the degree to which serious juvenile offenders respond to sanctions and/or treatment administered by the juvenile court. The policy question germane to this debate is finding the level of confinement within the juvenile justice system that maximizes the public safety and therapeutic benefits of institutional confinement. Unfortunately, research on this issue has been limited with regard to serious juvenile offenders. We use longitudinal data from a large sample of serious juvenile offenders from two large cities to 1) estimate a causal treatment effect of institutional placement, as opposed to probation, on future rate of rearrest and 2) investigate the existence of a marginal effect (i.e., benefit) for longer length of stay once the institutional placement decision had been made. We accomplish the latter by determining a dose-response relationship between the length of stay and future rates of rearrest and self-reported offending. The results suggest that an overall null effect of placement exists on future rates of rearrest or self-reported offending for serious juvenile offenders. We also find that, for the group placed out of the community, it is apparent that little or no marginal benefit exists for longer lengths of stay. Theoretical, empirical, and policy issues are outlined. [source] Women's Careers Beyond the Classroom: Changing Roles in a Changing WorldCURRICULUM INQUIRY, Issue 3 2001Nina Bascia Drawing from our own and others' research over the past decade and a half, we present four "readings," each illuminating a different dimension of women educators' career development, particularly their movement into work beyond the classroom. The majority of the participants in our studies are women who work for change in their classrooms, schools, and district organizations, using the opportunities, vehicles, and channels available,or apparent,to them. They do this work in professional and personal contexts that are continually changing, sometimes as a result of their own choices and actions and sometimes not. While there is a growing body of literature on women's movement into, and their lives in, educational administration, we are concerned here with the broader and more varied manifestations of leadership beyond the classroom. In the four readings, we bring together several strands in the literature on women educators' lives and careers. We first lay out the taken-for-granted oppositional contrasts in the educational discourses that have tended to obscure more complex understandings of work lives and careers. Next, we explore how the particular kinds of work available to women actually encourage some to move beyond narrow conceptions of the distinctions between classroom and nonclassroom work. Third, we discuss the developmental nature of individual career paths. Fourth, we note the spatial and temporal nature of leadership work by showing how it is influenced and changed by greater economic, social, and political forces. We believe that these multiple interpretations are required to understand the range and combination of influences that propel and compel women educators to take up various forms of leadership work beyond the classroom. [source] Effects of immersion water temperature on whole-body fluid distribution in humansACTA PHYSIOLOGICA, Issue 1 2004J. M. Stocks Abstract Aim:, In this study, we quantified acute changes in the intracellular and extracellular fluid compartments during upright neutral- and cold-water immersion. We hypothesized that, during short-term cold immersion, fluid shifts would be wholly restricted to the extracellular space. Methods:, Seven males were immersed 30 days apart: control (33.3 ° SD 0.6 °C); and cold (18.1 ° SD 0.3 °C). Posture was controlled for 4 h prior to a 60-min seated immersion. Results:, Significant reductions in terminal oesophageal (36.9 ° ± 0.1 °,36.3 ° ± 0.1 °C) and mean skin temperatures (30.3 ° ± 0.3 °,23.0 ° ± 0.3 °C) were observed during the cold, but not the control immersion. Both immersions elicited a reduction in intracellular fluid [20.17 ± 6.02 mL kg,1 (control) vs. 22.72 ± 9.90 mL kg,1], while total body water (TBW) remained stable. However, significant plasma volume (PV) divergence was apparent between the trials at 60 min [12.5 ± 1.0% (control) vs. 6.1 ± 3.1%; P < 0.05], along with a significant haemodilution in the control state (P < 0.05). Plasma atrial natriuretic peptide concentration increased from 18.0 ± 1.6 to 58.7 ± 15.1 ng L,1 (P < 0.05) during cold immersion, consistent with its role in PV regulation. We observed that, regardless of the direction of the PV change, both upright immersions elicited reductions in intracellular fluid. Conclusion:, These observations have two implications. First, one cannot assume that PV changes reflect those of the entire extracellular compartment. Second, since immersion also increases interstitial fluid pressure, fluid leaving the interstitium must have been rapidly replaced by intracellular water. [source] Slit-flow ektacytometry: Laser diffraction in a slit rheometerCYTOMETRY, Issue 1 2005Sehyun Shin Abstract Background Deformability of red blood cells (RBCs) is a determinant of blood flow resistance as RBCs pass through small capillaries of the microcirculation. Available techniques for measuring RBC deformability often require a washing process after each measurement, which is not optimal for day-to-day clinical use. Methods A laser diffraction technique has been combined with slit-flow rheometry, which shows significant advances in ektacytometric design, operation, and data analysis. The essential features of this design are its simplicity (ease of operation and no moving parts) and a disposable element that is in contact with the blood sample. Results With slit ektacytometry, the deformation of RBCs subjected to continuously decreasing shear stress in a slit flow can be quickly measured with extremely small quantities of blood. The measurements with the slit ektacytometer were compared with those of LORCA and a strong correlation was apparent. The deformability of the hardened RBCs was markedly lower than that of the normal RBCs. In addition, the young cells showed higher values of the elongation index than did the old cells. Conclusions The newly developed slit ektacytometer can measure RBC deformability with ease and accuracy. In addition, the slit ektacytometer can be easily used in a clinical setting owing to the incorporation of a disposable element that holds the blood sample. © 2005 Wiley-Liss, Inc. [source] Myosin diversity in the diatom Phaeodactylum tricornutum,CYTOSKELETON, Issue 3 2010Matthew B. Heintzelman Abstract This report describes the domain architecture of ten myosins cloned from the pennate diatom Phaeodactylum tricornutum. Several of the P. tricornutum myosins show similarity to myosins from the centric diatom Thalassiosira pseudonana as well as to one myosin from the oomycete Phytophthora ramorum. The P. tricornutum myosins, ranging in size from 126 kDa to over 250 kDa, all possess the canonical head, neck and tail domains common to most myosins, though variations in each of these domains is evident. Among the features distinguishing several of the diatom myosin head domains are N-terminal SH3-like domains, variations in or near the P-loop and Loop 1 regions close to the nucleotide binding pocket, and extended converter domains. Variations in the length of the neck domain or lever arm, defined by the light chain-binding IQ motifs, are apparent with the different diatom myosins predicted to contain from one to nine IQ motifs. Protein domains found within the P. tricornutum myosin tails include regions of coiled-coil structure, ankyrin repeats, CBS domain pairs, a PB1 domain, a kinase domain and a FYVE-finger motif. As many of these features have never before been characterized in myosins of any type, it is likely that these new diatom myosins will expand the repertoire of known myosin behaviors. © 2010 Wiley-Liss, Inc. [source] Sensitivity of alveolar macrophages to substrate mechanical and adhesive propertiesCYTOSKELETON, Issue 6 2006Sophie Féréol Abstract In order to understand the sensitivity of alveolar macrophages (AMs) to substrate properties, we have developed a new model of macrophages cultured on substrates of increasing Young's modulus: (i) a monolayer of alveolar epithelial cells representing the supple (,0.1 kPa) physiological substrate, (ii) polyacrylamide gels with two concentrations of bis-acrylamide representing low and high intermediate stiffness (respectively 40 kPa and 160 kPa) and, (iii) a highly rigid surface of plastic or glass (respectively 3 MPa and 70 MPa), the two latter being or not functionalized with type I-collagen. The macrophage response was studied through their shape (characterized by 3D-reconstructions of F-actin structure) and their cytoskeletal stiffness (estimated by transient twisting of magnetic RGD-coated beads and corrected for actual bead immersion). Macrophage shape dramatically changed from rounded to flattened as substrate stiffness increased from soft ((i) and (ii)) to rigid (iii) substrates, indicating a net sensitivity of alveolar macrophages to substrate stiffness but without generating F-actin stress fibers. Macrophage stiffness was also increased by large substrate stiffness increase but this increase was not due to an increase in internal tension assessed by the negligible effect of a F-actin depolymerizing drug (cytochalasine D) on bead twisting. The mechanical sensitivity of AMs could be partly explained by an idealized numerical model describing how low cell height enhances the substrate-stiffness-dependence of the apparent (measured) AM stiffness. Altogether, these results suggest that macrophages are able to probe their physical environment but the mechanosensitive mechanism behind appears quite different from tissue cells, since it occurs at no significant cell-scale prestress, shape changes through minimal actin remodeling and finally an AMs stiffness not affected by the loss in F-actin integrity. Cell Motil. Cytoskeleton 2006. © 2006 Wiley-Liss, Inc. [source] Post-karyokinesis centrosome movement leaves a trail of unanswered questionsCYTOSKELETON, Issue 3 2002Young Y. Ou Abstract The centrosome is a complex structure composed of a large number of proteins (pericentriolar material, PCM) usually organized around a pair of centrioles (or a centriole duplex). This structure is capable of nucleating and organizing microtubules, duplication, and motility. In general, episodes of dramatic centrosome movement correlate with periods of cellular reorganization and nowhere is cellular reorganization more apparent, or more important, than in the periods before and after cell division. It is now clear that centrosome movement occurs not only prior to cell division but also at its completion, in concert with cytokinesis. The focus of this review is the newly emerging picture of centrosome activity during the post-karyokinesis period and the role that this activity might play in the transition of cells from mitosis to interphase. Cell Motil. Cytoskeleton 51:123,132, 2002. © 2002 Wiley-Liss, Inc. [source] Remodeling of the actin cytoskeleton of target hepatocytes and NK cells during induction of apoptosisCYTOSKELETON, Issue 2 2001W. Marty Blom Abstract Natural Killer cells are immune cells that recognize and eliminate altered and non-self cells from the circulation. To study the interaction between NK cells and target cells, we set up an experimental system consisting of rat Interleukin-2 activated Natural Killer cells (A-NK cells) and rat hepatocytes with a masked Major Histocompatibility Complex (MHC). The masking of the MHC induces recognition of the hepatocytes by the NK cells as non-self. We showed that in vitro apoptosis is rapidly induced in the hepatocytes [Blom et al., 1999] after co-incubation with A-NK cells. Now we describe the morphological changes that occur during and after interaction of A-NK cells with hepatocytes. Confocal laser scanning microscopy showed that the actin cytoskeleton of the NK cells was remodeled during attack of hepatocytes. Some NK cells were in close contact with the hepatocytes while others had formed actin-containing dendrites of varying length that made contact with the hepatocytes. However, dendrite formation is not obligatory for induction of apoptosis because cells that were unable to form these did induce FAS-dependent apoptosis in hepatocytes. Apparently both direct as well as distant contact resulted in apoptosis. Formation of the dendrites was calcium-dependent as EGTA largely prevented it. Importantly, chelation of the calcium also suppressed killing of the hepatocytes. Within 1 h after addition of the A-NK cells, morphological changes in hepatocytes that are characteristic of apoptosis, such as the formation of apoptotic bodies and fragmented nuclei, became apparent. Specifically, the actin cytoskeleton of the hepatocytes was remodeled resulting in the formation of the apoptotic bodies. Inhibition of caspase activity by z-Val-Ala-DL-Asp-fluoromethylketone (100 ,M) partly protected against the rearrangement of the actin filaments in the hepatocytes. Cell Motil. Cytoskeleton 49:78,92, 2001. © 2001 Wiley-Liss, Inc. [source] The three-dimension finite element analysis of stress in posterior tooth residual root restored with postcore crownDENTAL TRAUMATOLOGY, Issue 1 2010Gang Fu Some researchers have analyzed the stress of the anterior teeth after postcore crown restoration, but the stress of the posterior teeth after such restoration has not been reported. We used three-dimension finite element methods to analyze the stress magnitude and distribution of remaining dentin in posterior tooth residual root restored with postcore crown. The binding material, loading direction, number, length and material of posts were studied. Methods:, The models of residual root of maxillary first molar restored with postcore crown were created by CT scanning, mimics software and abaqus software. Different number, length and material of posts were used in the modeling. The posts were cemented with zinc-phosphate cement or composited resin. A load of 240 N was applied to the occlusal surface in four directions and tensile, shear, and von Mises stresses were calculated. Result:, (i) The maximum stress on remaining dentin changed irregularly as the number and length of posts changed. (ii) The maximum stress on remaining dentin decreased slightly as elastic modulus of the material of posts increased. (iii) The maximum stress on bonding layer and remaining dentin was lower when bonded with resin luting agent than with zinc-phosphate cement. (iv) The maximum stress on remaining dentin increased markedly as loading angle increased. Conclusion:, The number, length, material of posts, bonding material and loading angle all have influence on the magnitude and distribution of stress. The influence of loading angle is most apparent. [source] Traumatised permanent teeth in 11,16-year-old Saudi Arabian children with a sensory impairment attending special schoolsDENTAL TRAUMATOLOGY, Issue 3 2003M. AlSarheed Abstract ,,,The aim of this study was to determine the prevalence of traumatised permanent teeth among sensory (visual (VI) and hearing (HI)) impaired children attending special schools in Riyadh, Saudi Arabia. All the dental injuries involved incisor teeth, and trauma was noted in 33 (6.7%) children attending government schools (control group) compared to 7 (9%) VI children and 24 (11.4%) HI children. Differences in the dental trauma only reached statistical significance between the HI and control group (P < 0.05). Gender differences were only apparent in the HI group, with males having higher levels of traumatised teeth. In addition, HI children aged 11,12 years were more prone to trauma than children in the control group of the same age (P < 0.05). In conclusion, sensory impaired children do have a tendency for more dental trauma. However, this was only statistically significant for HI children. Whereas a gender difference was most noticeable for the HI group, with males having higher levels of trauma, this was noticeable by its absence among VI children. [source] A Randomized Trial to Determine the Influence of Laser Therapy, Monopolar Radiofrequency Treatment, and Intense Pulsed Light Therapy Administered Immediately after Hyaluronic Acid Gel ImplantationDERMATOLOGIC SURGERY, Issue 5 2007MITCHEL P. GOLDMAN MD BACKGROUND Hyaluronic acid-based dermal fillers, such as hyaluronic acid gel (Restylane, Q-Medical AB, Uppsala, Sweden), are widely used for tissue augmentation of the nasolabial folds. Additional dermatologic treatments using infrared light, radiofrequency (RF), and intense pulsed light (IPL) are also important tools for facial rejuvenation. This study was designed to evaluate whether these therapies could be safely administered immediately after hyaluronic acid gel treatment without compromising the effect of the dermal filler. OBJECTIVE The objective of this study was to confirm or refute any possible subtractive effects of augmentation of the nasolabial folds when followed by 1,320-nm Nd:YAG laser, 1,450-nm diode laser, monopolar RF, and/or IPL treatments. METHODS Thirty-six patients with prominent nasolabial folds were treated with hyaluronic acid gel implantation on one side of the face and hyaluronic acid gel followed by one of the nonablative laser/RF/IPL therapies on the contralateral side of the face. RESULTS There were no statistically significant differences between wrinkle severity or global aesthetic scores for hyaluronic acid gel implantation alone and hyaluronic acid gel with laser/RF/IPL treatment at any time point. In a small sample, histologic changes were not apparent after laser/RF/IPL treatment. CONCLUSIONS Based on this small pilot study, laser, RF, and IPL treatments can safely be administered immediately after hyaluronic acid gel implantation without reduction in overall clinical effect. [source] Double-Blind, Randomized, Placebo-Controlled, Dose-Response Study of the Safety and Efficacy of Botulinum Toxin Type A in Subjects with Crow's FeetDERMATOLOGIC SURGERY, Issue 3 2005Nicholas J. Lowe MD Background Published evidence suggests that botulinum toxin type A (BTX-A) is an effective treatment for crow's feet. However, few dose-ranging studies have been performed. Objectives To assess the safety and efficacy of a single treatment with one of four doses of BTX-A (Botox/Vistabel, Allergan Inc) compared with placebo for the improvement of crow's feet. Methods Subjects received a single bilateral treatment of 18, 12, 6, or 3 U of BTX-A or placebo injected into the lateral aspect of the orbicularis oculi muscle (parallel-group, double,blind design). Investigators and subjects rated crow's feet severity at maximum smile on day 7 and at 30-day intervals from days 30 to 180. Results As observed by both investigators and subjects, all doses of BTX-A resulted in improvements in crow's feet severity when compared with placebo. A dose-dependent treatment effect for efficacy was observed, with higher doses having an increased magnitude and duration of effect. However, a clear differentiation between the 18 U and 12 U doses was not apparent. Few adverse events were reported, with no statistically significant differences between BTX-A and placebo in the incidence of subjects experiencing adverse events. Conclusion BTX-A is safe and effective in decreasing the severity of crow's feet, with 12 U per side suggested as the most appropriate dose. THIS STUDY WAS FUNDED BY ALLERGAN, WHICH WAS ALSO INVOLVED IN THE DESIGN AND CONDUCT OF THE STUDY; COLLECTION, MANAGEMENT, ANALYSIS, AND INTERPRETATION OF THE DATA; AND PREPARATION, REVIEW, AND APPROVAL OF THE MANUSCRIPT. DRS. LOWE AND FRACZEK ARE PAID CONSULTANTS FOR ALLERGAN, DRS. KUMAR AND EADIE ARE EMPLOYEES OF ALLERGAN, AND DRS. LOWE AND KUMAR HOLD STOCK OPTIONS. [source] The History of Dermatologic Surgical ReconstructionDERMATOLOGIC SURGERY, Issue 11 2000Daniel E. Zelac MD Over the last 40,50 years, reconstructive surgery in dermatology has undergone expansive growth and development. As dermatologists began to provide a greater array of surgical services during this period, it became apparent that new skills and techniques in the area of reconstruction would be required. Initially many of the procedures and concepts were adopted from other specialties, however, in the years since, significant contributions have been made by dermatologists which in turn have benefited other specialties as well. This review attempts to summarize some of the significant historical events and innovations that have established and supported dermatologic surgical reconstruction. [source] The Impact of AIDS on Rural Households in Africa: A Shock Like Any Other?DEVELOPMENT AND CHANGE, Issue 4 2002Carolyn Baylies In areas where HIV prevalence is high, household production can be significantly affected and the integrity of households compromised. Yet policy responses to the impact of HIV/AIDS have been muted in comparison to outcomes of other shocks, such as drought or complex political emergencies. This article looks at the reasons for the apparent under,reaction to AIDS, using data from Zambia, and examines recent calls to mitigate the effects of AIDS at household level. Critical consideration is directed at proposals relating to community safety nets, micro,finance and the mainstreaming of AIDS within larger poverty alleviation programmes. It is argued that effective initiatives must attend to the specific features of AIDS, incorporating both an assault on those inequalities which drive the epidemic and sensitivity to the staging of AIDS both across and within households. A multi,pronged approach is advocated which is addressed not just at mitigation or prevention, but also at emergency relief, rehabilitation and development. [source] Precarious Democratization and Local Dynamics in Niger: Micro,Politics in ZinderDEVELOPMENT AND CHANGE, Issue 5 2001Christian Lund Literature on the African state often finds it hard to specify what is state and what is not. The closer one gets to a particular political landscape, the more apparent it becomes that many institutions have something of a twilight character. This article argues that studies of local politics in Africa should focus on how the public authority of institutions waxes and wanes and how political competition among individuals and organizations expresses the notion of state and public authority. This is explored in the context of contemporary political struggles in Niger, played out in three different arenas in the region of Zinder around 1999, as home,town associations, chieftaincies and vigilante groups all take on the mantle of public authority in their dealings with what they consider to be their antithesis, the ,State'. [source] Risky Business: Economic Uncertainty, Market Reforms and Female Livelihoods in Northeast GhanaDEVELOPMENT AND CHANGE, Issue 5 2000Brenda Chalfin This article examines the implications of economic uncertainty for rural markets and the livelihoods of female traders. It does so through a case study of a community in northern Ghana caught in the throes of a structural adjustment-driven privatization initiative. In order to fully comprehend the nature of the economic uncertainties in which rural economic actors are enmeshed and the manner in which they resist, engage or engender these conditions, two theoretical lenses are interposed. One, focusing on structural dissolution and an overall process of rural, and especially female, disempowerment, is drawn from recent approaches to African political economy. The other, gleaned from the field of economic anthropology, attends to the agency and knowledge of rural entrepreneurs in the face of unstable and imperfect market conditions. By bringing together these different analytic traditions, the critical significance of uncertainty within the complex process of rural economic transformation and reproduction becomes evident. Rather than functioning as a diagnostic of economic crisis and insecurity, uncertainty can be a strategic resource integral to the constitution of markets, livelihoods and economic coalitions. Such a perspective, privileging the institutional potentials of local social practice, makes apparent the forceful role played by female traders in the structuring of rural marketing systems even in the face of externally-induced and sometimes dramatic shifts in material conditions. [source] Epigenetic regulation in neural stem cell differentiationDEVELOPMENT GROWTH & DIFFERENTIATION, Issue 6 2010Berry Juliandi The central nervous system (CNS) is composed of three major cell types , neurons, astrocytes, and oligodendrocytes , which differentiate from common multipotent neural stem cells (NSCs). This differentiation process is regulated spatiotemporally during the course of mammalian development. It is becoming apparent that epigenetic regulation is an important cell-intrinsic program, which can interact with transcription factors and environmental cues to modulate the differentiation of NSCs. This knowledge is important given the potential of NSCs to produce specific CNS cell types that will be beneficial for clinical applications. Here we review recent findings that address molecular mechanisms of epigenetic and transcription factor-mediated regulation that specify NSC fate during CNS development, with a particular focus on the developing mammalian forebrain. [source] Pleiotropic function of FGF-4: Its role in development and stem cellsDEVELOPMENTAL DYNAMICS, Issue 2 2009Nobuyoshi Kosaka Abstract Fibroblast growth factors (FGFs) were initially recognized as fibroblast-specific growth factor, and it is now apparent that these growth factors regulate multiple biological functions. The diversity of FGFs function is paralleled by the emerging diversity of interactions between FGF ligands and their receptors. FGF-4 is a member of the FGF superfamily and is a mitogen exhibiting strong action on numerous different cell types. It plays a role in various stages of development and morphogenesis, as well as in a variety of biological processes. Recent studies reveal the molecular mechanisms of FGF-4 gene regulation in mammalian cells, which is involved in the developmental process. Furthermore, FGF-4 also acts on the regulation of proliferation and differentiation in embryonic stem cells and tissue stem cells. In this review, we focus on the diverse biological functions of FGF-4 in the developmental process and also discuss its putative roles in stem cell biology. Developmental Dynamics 238:265,276, 2009. © 2008 Wiley-Liss, Inc. [source] | |||||||||||||||||||||||||||||||||||||