Home  About us  Contact
 

Et Al. (et + al)

Distribution by Scientific Domains
Life Sciences27%
Medical Sciences25%
Chemistry13%
Physics and Astronomy6%
Business, Economics, Finance and Accounting4%
Mathematics and Statistics4%
Earth and Environmental Science3%
Polymers and Materials Science3%
Psychology3%
Engineering3%
Humanities and Social Sciences2%
3 Other Domains7%
Distribution within Life Sciences
Neuroscience14%
Cell & Molecular Biology11%
Evolution7%
44 Other Subdomains68%

Kinds of Et Al.

  • Denni et al.
  • brown et al.
  • chen et al.
  • gray et al.
  • johnson et al.
  • kim et al.
    		•
  • la porta et al.
  • lee et al.
  • li et al.
  • lin et al.
  • martin et al.
  • miller et al.
    		•
  • porta et al.
  • power et al.
  • smith et al.
  • sun et al.
  • tutin et al.
  • wang et al.
    		•
  • white et al.
  • william et al.
  • zhang et al.

    • Terms modified by Et Al.

  • et al. model
  • et al. report
    		•
  • et al. show
  • et al. study
    		•

    Selected Abstracts

    THE CASE OF THE CRITICS WHO MISSED THE POINT: A REPLY TO WEBSTER ET AL.,

    CRIMINOLOGY AND PUBLIC POLICY, Issue 3 2006
    STEVEN D. LEVITT
    First page of article [source]

    TIME TO TEAR DOWN THE WALL: COMMENT ON DAWSON ET AL. (2005)

    ADDICTION, Issue 3 2005
    MARK B. SOBELL
    No abstract is available for this article. [source]

    STILL DIFFICULT TO KNOW WHAT ALCOHOL DEPENDENT INDIVIDUALS CAN RETURN TO CONTROLLED DRINKING: COMMENTS ON DAWSON ET AL. (2005)

    ADDICTION, Issue 3 2005
    DEBORAH HASIN
    No abstract is available for this article. [source]

    THE OMISSION OF CONFLICTING EVIDENCE FROM THE PAPER BY GOLLEDGE ET AL. (2008)

    GEOGRAFISKA ANNALER SERIES A: PHYSICAL GEOGRAPHY, Issue 4 2009
    DEREK FLINN
    ABSTRACT. In their paper on the last glaciation of Shetland, Golledge et al. (2008) concluded on the basis of a remote sensing study that during that period Shetland had been overrun by ice from Scandinavia. Since the method of study they used does not reveal the sense of the direction in which the ice flowed and since they ignored earlier ground-based work involving striations which do reveal the sense of direction of ice flow their conclusions have no scientific basis. [source]

    REPLY TO COMMENT BY THERIOT (2008) ON KACZMARSKA ET AL. (2006) (45:987,94)

    JOURNAL OF PHYCOLOGY, Issue 6 2009
    Article first published online: 30 NOV 200
    No abstract is available for this article. [source]

    Electrophysiologicai Characteristics of the Atrium in Sinus Node Dysfunction With and Without Postpacing Atrial Fihriliation

    PACING AND CLINICAL ELECTROPHYSIOLOGY, Issue 3 2000
    ANTONIO DE SISTI
    DE SISTI, A., ET AL.: Electrophysiologicai Characteristics of the Atrium in Sinus Node Dysfunction With and Without Postpacing Atrial Fibrillation . In patients with sinus node dysfunction (SND) with or without associated paroxysmal atrial fibrillation (AF), the effectiveness of atrial pacing in reducing the incidence of AF is not definitive. In addition, despite several studies involving large populations of implanted patients, little attention has been paid to the electrophysioiogicai (EP) atrial substrate and the effect of permanent atrial pacing. The aim of this study is to correlate EP data and the risk of AF after DDD device implantation. We reviewed FP data of 38 consecutive patients with SND. mean age 70 ± 8 years, who were investigated free of antiarrhythmic treatment, for the evaluation of the atrial substrate. We also considered as control group 25 subjects, mean age 63 ± 14 years, referred to our EP laboratory for unexplained syncope or various atrioventricular disturbances. Following pharmacological washout and at a drive cycle length of 600 ms. effective and functional refractory periods (ERP, FRP), Sl-Al and S2-A2 latency, Al and A2 conduction duration, and latent vulnerability index (EHP/A2) were measured. AF induction was tested with up to three extrastimuli at paced cycle lengths of 600 and 400 ms in 20 patients. Induction of sustained AF (> 30 seconds) was considered as the endpoint. P wave duration on the surface ECG in lead II/Vl was also measured. DDD pacing mode was chosen in all patients with the minimal atrial rate programmed between 60 and 75 beats/min (mean 64 ± 4 beats/min). After implantation, the patients were followed-up for 29 ± 17 months and clinically documented occurrence of AF was determined. When comparing patients with SND and subjects of the control group, we did not find any significant statistical differences in terms of ERP (237 ± 33 vs 250 ± 29 ms), FRP (276 ± 30 vs 280 ± 32 ms) and Sl-Al (39 ± 16 vs 33 ± 11 ms) and S2-A2 latency (69 ± 24 vs 63 ± 25 ms). In contrast, we observed significant differences regarding Al (55 ± 19 vs 39 ± 13 ms; P < 0.001), A2 (95 ± 34 vs 57 ± 18 ms; P < 0.001) and P wave duration (104 ± 18 vs 94 ± 15 ms; P < 0.05), and ERP/A2 (2.8 ± 1.2 vs 4.8 ± 1.6; P < 0.001). When comparing patients with (n = 11) or without (n =27) postpacing AF occurrence, we did not find any difference with reference to ERP, FRP. Sl-Al, S2-A2, Al duration, or follow-up duration. In patients with postpacing AF occurrence, A2 was longer (116 ± 41 vs 87 ± 27 ms; P < 0.01), FRP/A2 lower (2.1 ± 0.4 vs 3.1 ± 1.4; P < 0.05), P wave more prolonged (116 ± 22 vs 99 ± 14 ms; P < 0.01), and preexisting AF history predominant (6/11 vs 5/27 patients; P < 0.05). No difference was observed between patients with (n = 8) and without (n = 12) AF induction during the EP study. In patients with SND, the atrial refractoriness appears normal and the most important abnormality concerns conduction slowing disturbances. Persistence of AF despite pacing stresses the importance of mechanisms responsible for AF not entirely brady-dependent. In this setting, more prolonged atrial conduction disturbances, responsible for a low vulnerability index, and a preexisting history of AF enable us to identify a high risk patient group for AF in the follow-up. sinus node dysfunction, atrial fibrillation, electrophysiologicai study, atrial pacing [source]

    LETTER TO THE EDITOR REGARDING REIG ET AL., THERMOCOAGULATION OF THE GANGLION IMPAR OF WALTHER: DESCRIPTION OF A MODIFIED APPROACH.

    PAIN PRACTICE, Issue 4 2005
    NONONCOLOGICAL PAIN., PRELIMINARY RESULTS IN CHRONIC
    No abstract is available for this article. [source]

    ERRATUM TO RUTTEN ET AL. (2009)

    ARCHAEOMETRY, Issue 1 2010
    Article first published online: 22 DEC 200
    No abstract is available for this article. [source]

    Hierarchical Structure Recovery of Point-Sampled Surfaces

    COMPUTER GRAPHICS FORUM, Issue 6 2010
    Marco Attene
    I.3 COMPUTER GRAPHICS; I.3.5 Computational Geometry and Object Modeling,Object hierarchies Abstract We focus on the class of ,regular' models defined by Várady et al. for reverse engineering purposes. Given a 3D surface,,represented through a dense set of points, we present a novel algorithm that converts,,to a hierarchical representation,. In,, the surface is encoded through patches of various shape and size, which form a hierarchical atlas. If,,belongs to the class of regular models, then,,captures the most significant features of,,at all the levels of detail. In this case, we show that,,can be exploited to interactively select regions of interest on,,and intuitively re-design the model. Furthermore,,,intrinsically encodes a hierarchy of useful ,segmentations' of,. We present a simple though efficient approach to extract and optimize such segmentations, and we show how they can be used to approximate the input point sets through idealized manifold meshes. [source]

    Enhancing Neural Network Traffic Incident-Detection Algorithms Using Wavelets

    COMPUTER-AIDED CIVIL AND INFRASTRUCTURE ENGINEERING, Issue 4 2001
    A. Samant
    Researchers have presented freeway traffic incident-detection algorithms by combining the adaptive learning capability of neural networks with imprecision modeling capability of fuzzy logic. In this article it is shown that the performance of a fuzzy neural network algorithm can be improved through preprocessing of data using a wavelet-based feature-extraction model. In particular, the discrete wavelet transform (DWT) denoising and feature-extraction model proposed by Samant and Adeli (2000) is combined with the fuzzy neural network approach presented by Hsiao et al. (1994). It is shown that substantial improvement can be achieved using the data filtered by DWT. Use of the wavelet theory to denoise the traffic data increases the incident-detection rate, reduces the false-alarm rate and the incident-detection time, and improves the convergence of the neural network training algorithm substantially. [source]

    Vascular endothelial growth factor in edematous mouse embryos induced by retinoic acid in utero

    CONGENITAL ANOMALIES, Issue 2 2001
    Yoshiko Yasuda
    ABSTRACT, Vascular endothelial growth factor (VEGF) is induced by hypoxic environment and contributes to vascular formation in both developing embryos and adults. Exogenous retinoic acid (RA) induces avascular yolk sacs with anemic stunted embryos of day 9 and 10 of gestation when RA is given to pregnant mice on day 6, 6.5 or 7 of pregnancy (Yasuda et al., 1996). We undertook the present studies to find out whether VEGF is activated and plays any role in those RA-exposed embryos. Embryos were obtained from dams given 60 mg/kg of RA on day 6 or 7 of pregnancy and sacrificed three days later. Most RA-exposed embryos showed edematous swelling without prominent vascular nets, but had beating heart tubes on day 9 and day 10 of gestation. Microscopic examination of developing tissue components showed various degrees of degeneration, and distension of the dorsal aorta when the body cavity was dosed. Northern blot analysis revealed expression of VEGF mRNA in the RA-exposed and control embryos. The highest expression of VEGF mRNA was seen in the embryos of day 10 exposed to RA on day 7, and these embryos had a significantly lower ATP content than did the controls (p < 0.01). Immunoreactive VEGF was detectable in both experimental and control embryos; in the former it was especially visible in the distended neuroepithelium, endothelium and membranes. These VEGF-immunoreactive regions also expressed another permeability factor, bradykinin. These findings suggest that VEGF upregulated by hypoxic conditions in edematous embryos induced by RA exposure in utero acts as hyperpermeability. [source]

    Biodiversity Conservation in Agricultural Landscapes: Challenges and Opportunities of Coffee Agroforests in the Western Ghats, India

    CONSERVATION BIOLOGY, Issue 2 2010
    CLAUDE A. GARCIA
    agroforestería de café; Ghats Occidentales; medios de vida; mosaicos paisajísticos; proyectos integrados de conservación y desarrollo Abstract:,The new approaches advocated by the conservation community to integrate conservation and livelihood development now explicitly address landscape mosaics composed of agricultural and forested land rather than only protected areas and largely intact forests. We refer specifically to a call by Harvey et al. (2008) to develop a new approach based on six strategies to integrate biodiversity conservation with sustainable livelihoods in Mesoamerican landscape mosaics. We examined the applicability of this proposal to the coffee agroforests of the Western Ghats, India. Of the six strategies, only one directly addresses livelihood conditions. Their approach has a clear emphasis on conservation and, as currently formulated risks repeating the failures of past integrated conservation and development projects. It fails to place the aspirations of farmers at the core of the agenda. Thus, although we acknowledge and share the broad vision and many of the ideas proposed by this approach, we urge more balanced priority setting by emphasizing people as much as biodiversity through a careful consideration of local livelihood needs and aspirations. Resumen:,Los nuevos enfoques recomendados por la comunidad de conservación para integrar la conservación y el desarrollo ahora abordan explícitamente los mosaicos paisajísticos compuestos de tierras agrícolas y forestales en lugar de solo áreas protegidas y bosques casi intactos. Basado en seis estrategias para integrar la conservacion de la biodiversidad con modos de vida sustentables en los mosaicos paisajisticos de Mesoamerica. Nos referimos específicamente a la llamada de Harvey et al. (2008) para desarrollar un enfoque nuevo basado en seis estrategias para congraciar la conservación de la biodiversidad con modos de vida sustentables en los mosaicos paisajísticos de Mesoamérica. Examinamos la aplicabilidad de esta propuesta en los agrobosques de café de los Ghats occidentales en la India. Solo una de las seis estrategias mencionadas aborda directamente las condiciones de vida. La propuesta tiene un claro énfasis en la conservación y, tal como está formulada actualmente, falla en colocar las aspiraciones de los campesinos en el centro de la agenda. Corre pues el riesgo de repetir los fracasos de pasados proyectos integrados de conservación y desarrollo. Por lo tanto, aunque reconocemos y compartimos la amplia visión y muchas de las ideas de esta llamada, insistimos en una definición de prioridades balanceada que enfatice a la gente tanto como a la biodiversidad mediante una consideración cuidadosa de las necesidades y aspiraciones de los habitantes locales. [source]

    Significance of Specimen Databases from Taxonomic Revisions for Estimating and Mapping the Global Species Diversity of Invertebrates and Repatriating Reliable Specimen Data

    CONSERVATION BIOLOGY, Issue 2 2004
    RUDOLF MEIER
    More specifically, we demonstrate for a specimen database assembled during a revision of the robber-fly genus Euscelidia (Asilidae, Diptera) how nonparametric species richness estimators (Chao1, incidence-based coverage estimator, second-order jackknife) can be used to (1) estimate global species diversity, (2) direct future collecting to areas that are undersampled and/or likely to be rich in new species, and (3) assess whether the plant-based global biodiversity hotspots of Myers et al. (2000) contain a significant proportion of invertebrates. During the revision of Euscelidia, the number of known species more than doubled, but estimation of species richness revealed that the true diversity of the genus was likely twice as high. The same techniques applied to subsamples of the data indicated that much of the unknown diversity will be found in the Oriental region. Assessing the validity of biodiversity hotspots for invertebrates is a formidable challenge because it is difficult to decide whether species are hotspot endemics, and lists of observed species dramatically underestimate true diversity. Lastly, conservation biologists need a specimen database analogous to GenBank for collecting specimen records. Such a database has a three-fold advantage over information obtained from digitized museum collections: (1) it is shown for Euscelidia that a large proportion of unrevised museum specimens are misidentified; (2) only the specimen lists in revisionary studies cover a wide variety of private and public collections; and (3) obtaining specimen records from revisions is cost-effective. Resumen:,Sostuvimos que los millones de registros de especimenes publicados en miles de revisiones taxonómicas en décadas anteriores son una fuente de información costo-efectiva de importancia crítica para la incorporación de invertebrados en decisiones de investigación y conservación. Más específicamente, para una base de datos de especimenes de moscas del género Euscelidia (Asilidae, Diptera) demostramos como se pueden utilizar estimadores no paramétricos de riqueza de especies (Chao 1, estimador de cobertura basado en incidencia, navaja de segundo orden) para (1) estimar la diversidad global de especies, (2) dirigir colecciones futuras a áreas que están sub-muestreadas y/o probablemente tengan especies nuevas y (3) evaluar si los sitios globales de importancia para la biodiversidad basados en plantas de Myers et al. (2000) contienen una proporción significativa de invertebrados. Durante la revisión de Euscelidia el número de especies conocidas fue más del doble, pero la estimación de riqueza de especies reveló que la diversidad real del género probablemente también era el doble. Las mismas técnicas aplicadas a las sub-muestras de datos indicaron que gran parte de la diversidad no conocida se encontrará en la Región Oriental. La evaluación de la validez de sitios de importancia para la biodiversidad de invertebrados es un reto formidable porque es difícil decidir si las especies son endémicas de esos sitios y si las listas de especies observadas subestiman dramáticamente la diversidad real. Finalmente, los biólogos de la conservación requieren de una base de datos de especimenes análoga a GenBank, para obtener registros de especimenes. Dicha base de datos tiene una triple ventaja sobre la información obtenida de colecciones de museos digitalizadas. (1) Se muestra para Euscelidia que una gran proporción de especimenes de museo no revisados están mal identificados. (2) Sólo las listas de especimenes en estudios de revisión cubren una amplia variedad de colecciones privadas y públicas. (3) La obtención de registros en revisiones es costo-efectiva. [source]

    Application of the New Keystone-Species Concept to Prairie Dogs: How Well Does It Work?

    CONSERVATION BIOLOGY, Issue 6 2000
    Natasha B. Kotliar
    This prompted Power et al. (1996) to refine the definition: keystone species have large effects on community structure or ecosystem function (i.e., high overall importance), and this effect should be large relative to abundance (i.e., high community importance). Using prairie dogs (Cynomys spp.) as an example, I review operational and conceptual difficulties encountered in applying this definition. As applied to prairie dogs, the implicit assumption that overall importance is a linear function of abundance is invalid. In addition, community importance is sensitive to abundance levels, the definition of community, and sampling scale. These problems arise largely from the equation for community importance, as used in conjunction with removal experiments at single abundance levels. I suggest that we shift from the current emphasis on the dualism between keystone and nonkeystone species and instead examine how overall and community importance vary (1) with abundance, (2) across spatial and temporal scales, and (3) under diverse ecological conditions. In addition, I propose that a third criterion be incorporated into the definition: keystone species perform roles not performed by other species or processes. Examination of how these factors vary among populations of keystone species should help identify the factors contributing to, or limiting, keystone-level functions, thereby increasing the usefulness of the keystone-species concept in ecology and conservation. Although the quantitative framework of Power et al. falls short of being fully operational, my conceptual guidelines may improve the usefulness of the keystone-species concept. Careful attention to the factors that limit keystone function will help avoid misplaced emphasis on keystone species at the expense of other species. Resumen: Se ha sugerido que el concepto de especie pilar no sea usado más en ecología y conservación, principalmente debido a que el concepto ha sido pobremente definido. Esto instigó a Power et al. (1996) a refinar la definición: las especies pilar tienen grandes efectos en la estructura de una comunidad o la función de un ecosistema (alta importancia en lo general), y este efecto debe ser grande en relación con la abundancia (alta importancia en la comunidad). Usando los perros de pradera (Cynomys spp) como ejemplo, revisé las dificultades operativas y conceptuales encontradas durante la aplicación de esta definición. Al aplicarse a perros de pradera, la suposición implícita de que la importancia en lo general es una función lineal de la abundancia es inválida. Además, la importancia en la comunidad es sensible a los niveles de abundancia, a la definición de comunidad y a la escala de muestreo. Estos problemas surgen, en gran medida, de la ecuación para la importancia en la comunidad, al ser usada conjuntamente con experimentos de remoción a un solo nivel de abundancia. Sugiero que el énfasis actual en la dualidad sobre especies pilares/no pilares cambie para examinar cómo varía la importancia en lo general y en la comunidad; (1) con la abundancia, (2) a lo largo de escalas espaciales y temporales, y (3) bajo diversas condiciones ecológicas. Además, propongo que sea incorporado un tercer criterio en la definición: las especies pilar llevan a cabo funciones no llevadas a cabo por otras especies o procesos. El análisis de cómo varían estos factores entre poblaciones de especies pilar ayudará a identificar los factores que contribuyen, o limitan las funciones a nivel pilar, incrementando con ello la utilidad del concepto de especie pilar en ecología y conservación. Aunque el marco de trabajo cuantitativo de Power et al. no llega a ser completamente operacional, mis guías conceptuales pueden mejorar la utilidad de este concepto. Una atención especial a los factores que limitan el funcionamiento pilar ayudaría a evitar un énfasis mal ubicado en especies pilar a costa de otras especies. [source]

    The Association between Auditor Choice, Ownership Retained, and Earnings Disclosure by Firms Making Initial Public Offerings,

    CONTEMPORARY ACCOUNTING RESEARCH, Issue 1 2002
    Paul A. Copley
    Abstract Using a system of three simultaneous equations, we test the predictions of Datar, Feltham, and Hughes 1991 and Hughes 1986 between auditor choice, earnings disclosures, and retained ownership in U.S. firms making initial public offerings of securities. Using a sample of initial public offerings between 1990 and 1997, we find that the demand for high-quality auditors increases with firm risk. Additionally, we find that auditor choice, earnings disclosure, and risk are determinants of retained ownership, which is consistent with the predictions of Datar et al. and Hughes that auditor choice and direct disclosure are substitute signals for ownership retention. Further, our results suggest that the signals chosen (i.e., retained ownership, auditor choice, and disclosure) are related through their cost structures and are chosen jointly to minimize the overall cost to the entrepreneur. [source]

    THE EFFICIENCY OF SEQUESTERING CARBON IN AGRICULTURAL SOILS

    CONTEMPORARY ECONOMIC POLICY, Issue 2 2001
    GR Pautsch
    Agricultural tillage practices are important human-induced activities that can alter carbon emissions from agricultural soils and have the potential to contribute significantly to reductions in greenhouse gas emission (Lal et al., The Potential of U.S. Cropland, 1998). This research investigates the expected costs of sequestering carbon in agricultural soils under different subsidy and market-based policies. Using detailed National Resources Inventory data, we estimate the probability that farmers adopt conservation tillage practices based on a variety of exogenous characteristics and profit from conventional practices. These estimates are used with physical models of carbon sequestration to estimate the subsidy costs of achieving increased carbon sequestration with alternative subsidy schemes. [source]

    Earnings Management and Corporate Governance in Asia's Emerging Markets

    CORPORATE GOVERNANCE, Issue 5 2007
    Chung-Hua Shen
    This paper studies the impacts of corporate governance on earnings management. We use firm-level governance data, taken from Credit Lyonnais Security Asia (CLSA), of nine Asian countries, in addition to the country-level governance data used in past studies. Our conclusion is as follows. First, firms with good corporate governance tend to conduct less earnings management. Second, there is a size effect for earnings smoothing, that is, large size firms are prone to conduct earnings smoothing, but good corporate governance can mitigate the effect on average. Third, there is a turning point for leverage effect, i.e. when the governance index is large, leverage effect exists, otherwise reverse leverage effect exists. It shows that a highly leveraged firm with poor governance is prone to be scrutinised closely and thus finds it harder to fool the market by manipulating earnings. Fourth, firms with higher growth (lower earnings yield) are prone to engage in earnings smoothing and earnings aggressiveness, but good corporate governance can mitigate the effect. Finally, firms in stronger anti-director rights countries tend to exhibit stronger earnings smoothing. This counter-intuitive result is different from Leuz et al. (2003). [source]

    Universal Owners: challenges and opportunities

    CORPORATE GOVERNANCE, Issue 3 2007
    James Hawley
    This special issue of Corporate Governance is devoted to the concept of "universal ownership" (UO) and grows out of a conference of universal owners, institutional investors, investment professionals and academics held in April 2006 at Saint Mary's College of California, under the sponsorship of the Center for the Study of Fiduciary Capitalism (A report of the conference is available at http://www.fidcap.org). Four of the seven articles in this issue are based on papers presented at the conference, while an additional three (by Lydenberg, Syse and Gjessing, and Lippman et al.) were written specifically for this issue. The conference purposefully developed a practitioners' perspective on universal ownership and these articles reflect this orientation, although each article in its own way breaks new ground which academics, policy researchers and practitioners can and should develop. [source]

    Alcohol expectancies in convicted rapists and child molesters

    CRIMINAL BEHAVIOUR AND MENTAL HEALTH, Issue 2 2001
    Anu S. Aromäki PhD
    Background Previous findings suggest that cognitive factors and expectancies related to drinking can mediate subjective sexual arousal as well as aggression in men. Our aim was to investigate the drinking habits and alcohol-related expectancies that might predispose men to sexually aggress in two groups of sexual offenders. Method Men convicted of rape (n = 10) were compared with men convicted of child molesting (n = 10) and with control subjects (n = 31). Current drinking habits (while not in prison) were assessed by self-report, and the extent of alcohol abuse was mapped by the Michigan Alcoholism Screening Test (MAST; Selzer, 1971). Cognitive expectancies related to alcohol use were explored by the standard Alcohol Expectancy Questionnaire (AEQ; Brown et al., 1980). Results The majority of the men who committed rape (70%) but only a third of the men convicted of child molesting were diagnosed with antisocial personality disorder. Alcohol abuse was common in men convicted of both rape and child molesting and the men convicted of rape expected significantly more positive effects from drinking than the control group. Both sex offender groups were the only groups to express significant alcohol-related cognitive expectancies linked to arousal and aggression. Expectancy patterns were directly linked to the antisocial personality characteristics. Conclusion Alcohol abuse is common in men who commit both rape and child molesting. Heavy drinking and the anticipation of alcohol effects such as sexual enhancement, arousal and aggression may facilitate sexual aggression in offenders with antisocial personality disorder. Copyright © 2001 Whurr Publishers Ltd. [source]

    VIOLENCE AMONG ADOLESCENTS LIVING IN PUBLIC HOUSING: A TWO-SITE ANALYSIS,

    CRIMINOLOGY AND PUBLIC POLICY, Issue 1 2003
    TIMOTHY O. IRELAND
    Research Summary: Current knowledge about violence among public housing residents is extremely limited. Much of what we know about violence in and around public housing is derived from analysis of Uniform Crime Report (UCR) data or victimization surveys of public housing residents. The results of these studies suggest that fear of crime among public housing residents is high and that violent offense rates may be higher in areas that contain public housing compared with similar areas without public housing. Yet, "[r]ecorded crime rates (and victimization rates) are an index not of the rate of participation in crime by residents of an area, but of the rate of crime (or victimization) that occurs in an area whether committed by residents or non-residents" (Weatherburn et al., 1999:259). Therefore, neither UCR nor victimization data measurement strategies address whether crime in and around public housing emanates from those who reside in public housing. Additionally, much of this research focuses on atypical public housing,large developments with high-rise buildings located in major metropolitan areas. To complement the existing literature, we compare rates of self-reported crime and violence among adolescents who reside in public housing in Rochester, N.Y., and Pittsburgh, Pa., with adolescents from the same cities who do not live in public housing. In Rochester, property crime and violence participation rates during adolescence and early adulthood among those in public housing are statistically equivalent to participation rates among those not in public housing. In Pittsburgh, living in public housing during late adolescence and early adulthood, particularly in large housing developments,increases the risk for violent offending, but not for property offending. The current study relies on a relatively small number of subjects in public housing at any single point in time and is based on cross-sectional analyses. Even so, there are several important policy implications that can be derived from this study, given that it moves down a path heretofore largely unexplored. Policy Implications: If replicated, our findings indicate that not all public housing is inhabited disproportionately by those involved in crime; that to develop appropriate responses, it is essential to discover if the perpetrators of violence are residents or trespassers; that policy should target reducing violence specifically and not crime in general; that a modification to housing allocation policies that limits, to the extent possible, placing families with children in late adolescence into large developments might reduce violence perpetrated by residents; that limited resources directed at reducing violence among residents should be targeted at those developments or buildings that actually have high rates of participation in violence among the residents; and that best practices may be derived from developments where violence is not a problem. [source]

    Comments on papers reporting IR-spectra and other data of alleged L-alanine alaninium nitrate and L-alanine sodium nitrate crystals

    CRYSTAL RESEARCH AND TECHNOLOGY, Issue 7 2009
    M. Fleck
    Abstract We argue that the IR- and Raman-spectra of "L-alanine alaninium nitrate" given in "Investigation on the growth, optical behaviour and factor group of an NLO crystal: L-Alanine Alaninium nitrate" by Aravindan et al., Cryst. Res. Technol. 42, 1097 (2007), actually concern L-Alanine. Correspondingly, the data presented in "A comparative study on the growth and characterization of nonlinear optical amino acid crystals: L-Alanine (LA) and L-alanine alaninium nitrate (LAAN)" by Aravindan et al., Spectrochim. Acta A 71, 297 (2008), seems to be erroneous, as is "Synthesis, Growth, and Characterization of a New Semiorganic Nonlinear Optical Crystal: L-Alanine Sodium Nitrate (LASN)", Sethuraman, et al., Cryst. Growth Des. 8, 1863 (2008). In these papers properties and data were reported for L-Alanine compounds that actually are L-Alanine crystals and, in addition, unit cell parameters were given that seem to have been copied from other papers. (© 2009 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) [source]

    Arnold Heller and the lymph pump

    ACTA PHYSIOLOGICA, Issue 3 2005
    K. Aukland
    Abstract This article reviews studies on lymph propulsion in the lymph vessels by active contraction of the vessels, first described by Arnold Heller in 1869 in German language, and here translated into English. His observations were first confirmed by Beatrice Carrier (1926) and Howard Flory et al. (1927), and several groups were active up to World war II. Few publications appeared in the period 1940--1960, followed by increasing activity and development of new experimental techniques for use both in various experimental animals and in humans. Recently it has been shown that passive lymph flow may add to active propulsion. Both mechanisms depend on lymph formation, i.e. the uptake of interstitial fluid by the initial lymph vessels which is still not well understood. [source]

    Learning from Difference: Considerations for Schools as Communities

    CURRICULUM INQUIRY, Issue 3 2000
    Carolyn M. Shields
    In today's highly complex and heterogeneous public schools, the current notion of schools as homogeneous communities with shared beliefs, norms, and alues is inadequate. Drawing on Barth's (1990) question of how to use ifference as a resource, I take up ideas from feminism, multiculturalism, and inclusive education to consider the development of community in schools. I argue that despite the valuable contributions of these theoretical perspectives, each lso includes the potential for increased fragmentation and polarization. As we consider how to use differences as a foundation for community, it is important ot to reify any particular perspective, thus marginalizing others and erecting new barriers. Explicitly embracing the need to identify and respect difference, being open to new ideas without taking an exclusionary position, and committing to ongoing participation in dialogical processes may help schools to develop as more authentic communities of difference. Among the dominant issues identified in today's climate of turbulent educational reform are concerns about how to restructure schools to ensure equality of student opportunity and excellence of instruction (Elmore, 1990; Lieberman, 1992; Murphy, 1991). Many proposals include modifying present leadership and governance structures, overcoming the hegemony of existing power bases, developing mechanisms for accountability, enhancing professionalism, and co-ordinating community resources. One of the suggestions frequently made to address these issues is to change from a focus on schools as organizations to a recognition of schools as communities (Barth, 1990; Fullan, 1993; Lupart & Webber, 1996; Senge, 1990). However, despite the widespread use of the metaphor of community as an alternative to the generally accepted concept of schools as rational or functional organizations, there seems to be little clarity about the concept of community, what it might look like, how it might be implemented, or what policies might sustain it. Indeed, theories about schools as communities have often drawn from Tönnies (1887/1971) concept of gemeinschaft,a concept which perhaps evokes a more homogeneous and romanticized view of the past than one which could be helpful for improving education in today's dynamic, complex, and heterogeneous context (Beck & Kratzer, 1994; Sergiovanni, 1994a). More recently, several writers (Fine et al., 1997; Furman, 1998; Shields & Seltzer, 1997) have advanced the notion of communities of otherness or difference. These authors have suggested that rather than thinking of schools as communities that exist because of a common affiliation to an established school ethos or tradition, it might be more helpful to explore an alternative concept. A school community founded on difference would be one in which the common centre would not be taken as a given but would be co-constructed from the negotiation of disparate beliefs and values as participants learn to respect, and to listen to, each other. In this concept, bonds among members are not assumed, but forged, and boundaries are not imposed but negotiated. Over the past eight years, as I have visited and worked with a large number of schools trying earnestly to address the needs of their diverse student bodies, I have become increasingly aware of the limitations of the concept of community used in the gemeinschaft sense with its emphasis on shared values, norms, and beliefs, and have begun to reflect on the question framed by Barth (1990): ,How can we make conscious, deliberate use of differences in social class, gender, age, ability, race, and interest as resources for learning?' (p. 514). In this article, I consider how learning from three of these areas of difference: gender, race, and ability, may help us to a better understanding of educational community. This article begins with some illustrations and examples from practice, moves to consider how some theoretical perspectives may illuminate them, and concludes with reflections on how the implications of the combined reflections on practice and theory might actually help to reconceptualize and to improve practice. While it draws heavily on questions and impressions which have arisen out of much of my fieldwork, it is not intended to be an empirical paper, but a conceptual one,one which promotes reflection and discussion on the concept of schools as communities of difference. The examples of life in schools taken from longitudinal research studies in which I have been involved demonstrate several common ways in which difference is dealt with in today's schools and some of the problems inherent in these approaches. Some ideas drawn from alternative perspectives then begin to address Barth's question of how to make deliberate use of diversity as a way of thinking about community. Taken together, I hope that these ideas will be helpful in creating what I have elsewhere called ,schools as communities of difference' (Shields & Seltzer, 1997). [source]

    Critical Thoughts on Teaching Standard English

    CURRICULUM INQUIRY, Issue 2 2000
    Barbara L. Speicher
    This article exposes four assumptions that underlie most discussions of Standard English. First, spoken English equates to written English. Substantial evidence demonstrates that this equation is both misleading and false. Second, spoken and written English are equally amenable to standardization. This is also fallacious. We will use Prototype Theory (Rosch et al., 1976) and Standard Ideology (Milroy and Milroy, 1991) to explore how broadly shared notions about standard language have led to this belief. Third, Standard English is the language of the workplace and essential for social mobility. While we do not refute this assumption, we do explore the discrimination that stems from it. Fourth, Standard English is the language of the classroom. This assumption has never been systematically tested in the literature by examining the language that teachers use. Nor is it clear that teachers believe they do or should impose an idealized spoken form on their students. [source]

    Cells meeting our immunophenotypic criteria of endothelial cells are large platelets

    CYTOMETRY, Issue 2 2007
    Michiel H. Strijbos
    Abstract Background Circulating endothelial cells (CEC) are shed from damaged vasculature, making them a rational choice to serve as surrogate marker for vascular damage. Currently, various techniques and CEC definitions are in use, and their standardization and validation is needed. A flow cytometric single platform assay defining CEC as forward light scatter (FSC)low-to-intermedate, sideward light scatter (SSC)low, CD45,, CD31++ and CD146+ is a promising approach to enumerate CEC because of its simplicity (Mancuso et al., Blood 2001;97:3658,3661). Here, we set out to confirm the endothelial nature of these cells. Methods We isolated cells with a FSClow-to-intermediate, SSClow, CD31++, CD45dim immunophenotype (termed "cells meeting our immunophenotypic criteria for endothelial cells" [CMOIC]) from healthy donors to study the expression of endothelium-associated markers using several techniques. Special attention was paid to reagents identifying the endothelial cell-specific marker CD146. We compared antigen expression patterns of CMOIC with those of the HUVEC endothelial cell line and lymphocytes. Electron microscopy was used to detect the presence of endothelial cell-specific Weibel,Palade bodies in the sorted cells. Results CD146 expression was negative on CMOIC for all tested CD146 mAbs, but positive on HUVEC cells and a minor subset of T lymphocytes. Using flow cytometry, we found no expression of any endothelium-associated marker except for CD31 and CD34. HUVEC cells were positive for all endothelial markers except for CD34. Evaluation of CMOIC morphology showed a homogenous population of cells with a highly irregular nucleus-like structure and positive endothelial immunohistochemistry. CMOIC contained neither nuclei nor DNA. Electron microscopy revealed the absence of a nucleus, the absence of endothelial specific Weibel,Palade bodies, and revealed CMOIC to be large platelets. Conclusion The vast majority of cells with the immunophenotype FSClow-to-intermediate, SSClow, CD45,, CD31++ do not express CD146 and are large platelets rather than endothelial cells. © 2007 Clinical Cytometry Society. [source]

    Lithium and KB-R7943 effects on mechanics and energetics of rat heart muscle

    ACTA PHYSIOLOGICA, Issue 1 2002
    P. Bonazzola
    ABSTRACT The role of calcium influx on energy expenditure during cardiac contraction was studied. For this purpose, the described ability of lithium and KB-R 7943 (KBR) to diminish Ca entry through Na,Ca exchanger (Ponce-Hornos & Langer, J Mol Cell Cardiol 1980, 12, 1367, Satoh et al., Circulation 2000, 101, 1441) were used. In isolated contractions (contractions elicited after at least 5 min of rest) LiCl 45 mmol L,1 decreased pressure developed and pressure,time integral from 42.3 ± 2.7 and 14.5 ± 1.2 to 32.1 ± 3.4 mN mm,2 and 8.3 ± 0.9 mN mm,2 s, respectively. A similar effect was observed in regular contractions (at 0.16 Hz stimulation). The presence of KBR (5 ,mol L,1) in the perfusate induced a slight but not significant decrease in pressure developed and pressure,time integral in steady-state contractions. As it was previously described, the heat involved in a heart muscle contraction can be decomposed into several components (H1, H2, H3 and H4), but only one (H3) was associated with force generation. While H3 decreased with lithium in both types of contractions, H3/PtI ratio remained unaltered, indicating that the economy for pressure maintenance was unaffected. To further investigate the role of Ca entry on force development, a condition in which the contraction is mainly dependent on extracellular calcium was studied. An ,extra' stimulus applied 200 ms after the regular one in a muscle stimulated at 0.16 Hz induces a contraction with this characteristic (Marengo et al., Am J Physiol 1999, 276, H309). Lithium induced a strong decrease in pressure,time integral and H3 associated with this contraction (43 and 45%, respectively) with no change in H3/PtI ratio. Lithium also reduced (53%) an energy component (H2) associated with Ca cycling. The use of KBR showed qualitatively similar results [i.e. a 33% reduction in pressure,time integral associated with the extrasystole (ES) with no changes in H3/PtI ratio and a 30% reduction in the H2 component]. Li and KBR effects appear to be additive and in the presence of 45 mmol L,1 Li and 5 ,mol L,1 KBR the extrasystole was abolished in 77%. Lithium and KBR effects particularly for the extrasystole can be explained through the inhibition of Ca entry via Na,Ca exchange giving support to the participation of the Na,Ca exchanger in the Ca influx from the extracellular space. In addition, the results also suggest the possibility of an effect of Li on an additional Ca sensitive locus (different than the Na,Ca exchanger). In this connection, in isolated contractions lithium decreased the energy release fraction related to mitochondrial processes (H4) increasing the economy of the overall cardiac contraction. [source]

    Strikingly fast microtubule sliding in bundles formed by Chlamydomonas axonemal dynein,

    CYTOSKELETON, Issue 6 2010
    Susumu Aoyama
    Abstract Chlamydomonas axonemal extracts containing outer-arm dynein bundle microtubules when added in the absence of ATP. The bundles dissociate after addition of ATP (Haimo et al., Proc Natl Acad Sci USA 76:5759,5768, 1979). In the present study, we investigated the ATP-induced bundle dissociation process using caged ATP. Application of ,0.5 mM ATP induced microtubule sliding at ,30 ,m·s,1, which was 1.5 times faster than the microtubule sliding observed in protease-treated axonemes and five times faster than microtubule gliding on glass surfaces coated with outer-arm dynein. Bundles formed by mutant dynein molecules that lack one of the three heavy chains (HCs) displayed similar high-speed intermicrotubule sliding. These results suggest that Chlamydomonas outer-arm dynein molecules, when aligned, can translocate microtubules at high speed and that the high-speed sliding under load-free conditions does not require the complete set of the three HCs. It is likely that each of the three HCs has the ability to produce high-speed sliding, which should be an important property for their cooperation. © 2010 Wiley-Liss, Inc. [source]

    Interactions of MAP/microtubule affinity regulating kinases with the adaptor complex AP-2 of clathrin-coated vesicles

    CYTOSKELETON, Issue 8 2009
    Gerold Schmitt-Ulms
    Abstract MARK [microtubule-associated proteins (MAPs)/microtubule affinity regulating kinase]/Par-1 (partition defective) phosphorylate MAPs tau, MAP2 and MAP4 at KXGS motifs and thereby regulate microtubule dynamics and transport processes in cells [Drewes et al., Cell1997;89:297,308]. We report here that MARK copurifies with clathrin-coated vesicles (CCVs) via interaction with the adaptor complex AP-2. The adaptin binding site on MARK includes the regulatory loop of its catalytic domain. Immunofluorescence demonstrates the colocalization of MARK with AP-2 and clathrin, as well as other MARK-interacting proteins such as PAK5. The results are consistent with an observed influence of MARK on the trafficking of CCVs. Cell Motil. Cytoskeleton 2009. © 2009 Wiley-Liss, Inc. [source]

    Fibroblast elongation and dendritic extensions in constrained versus unconstrained microtissues

    CYTOSKELETON, Issue 3 2009
    Dylan M. Dean
    Abstract Cytoskeletal tension is fundamental to many biological processes, including germ layer sorting during embryogenesis [Krieg et al., 2008]. In vitro, such tension influences cell sorting in self-assembled, 3D microtissues and can be of sufficient magnitude to cause complex-shaped microtissue failure [Dean et al., 2007]. To examine the process of failure under cell-derived tension, we subjected normal human fibroblasts (NHFs) to directed self-assembly [Dean et al., 2007] in micro-molds designed to yield self-constraining microtissues. As cells contracted in this assay, the constrained microtissues narrowed, thinned and ultimately failed at their midpoints. By adding small numbers of GFP+ cells, changes in cell movement and morphology were assessed and compared to those of unconstrained microtissues. We found that cells formed numerous dendritic extensions within an hour of self-assembly and retracted these extensions as they elongated up to 30 times their initial diameter (,600 ,m) just prior to failure. Surprisingly, significant coordination in cell motility was observed over large distances within microtissues. Pharmacologic interventions showed that failure was myosin II and Rho kinase dependent and inhibition of failure resulted in shorter cells with greater numbers of extensions. These findings further our understanding of cellular self-assembly and introduce the use of GFP+ cells with directed self-assembly as a scaffold-free analogue to fibroblast-populated collagen gels (FPCGs). Cell Motil. Cytoskeleton 2009. © 2009 Wiley-Liss, Inc. [source]

    Morphological irregularities and features of resistance to apoptosis in the dcp-1/pita double mutated egg chambers during Drosophila oogenesis

    CYTOSKELETON, Issue 1 2005
    Ioannis P. Nezis
    Abstract In the present study, we demonstrate the most novel characteristic morphological features of Drosophila egg chambers lacking both dcp-1 and pita functions in the germline cells. Dcp-1 is an effector caspase and it has been previously shown to play an important role during Drosophila oogenesis [McCall and Steller, 1998 : Science 279 : 230,234; Laundrie et al., 2003 : Genetics 165 : 1881,1888; Peterson et al., 2003 : Dev Biol 260 : 113,123]. The completion of sequencing and annotation of the Drosophila genome has revealed that the dcp-1 gene is nested within an intron of another distinct gene, called pita, a member of the C2H2 zinc finger protein family that regulates transcriptional initiation. The dcp-1,/,/pita,/, nurse cells exhibit euchromatic nuclei (delay of apoptosis) during the late stages of oogenesis, as revealed by conventional light and electron microscopy. The phalloidin-FITC staining discloses significant defects in actin cytoskeleton arrangement. The actin bundles fail to organize properly and the distribution of actin filaments in the ring canals is changed compared to the wild type. The oocyte and the chorion structures have been also modified. The oocyte nucleus is out of position and the chorion appears to contain irregular foldings, while the respiratory filaments obtain an altered morphology. The dcp-1,/,/pita,/, egg chambers do not exhibit the rare events of spontaneously induced apoptosis, observed for the wild type flies, during mid-oogenesis. Interestingly, the mutated egg chambers are protected by staurosporine-induced apoptosis in a percentage of 40%, strongly suggesting the essential role of dcp-1 and/or pita during mid-oogenesis. Cell Motil. Cytoskeleton 60:14,23, 2005. © 2004 Wiley-Liss, Inc. [source]