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Terms modified by Same Selected AbstractsTHE ABSENCE OF EVIDENCE IS NOT THE SAME AS EVIDENCE FOR ABSENCE!ADDICTION, Issue 3 2008JØRGEN G. BRAMNESS No abstract is available for this article. [source] A case-based reasoning approach to derive object-oriented models from software architecturesEXPERT SYSTEMS, Issue 4 2010German L. Vazquez Abstract: Software architectures are very important to capture early design decisions and reason about quality attributes of a system. Unfortunately, there are mismatches between the quality attributes prescribed by the architecture and those realized by its object-oriented implementation. The mismatches decrease the ability to reason architecturally about the system. Developing an object-oriented materialization that conforms to the original architecture depends on both the application of the right patterns and the developer's expertise. Since the space of allowed materializations can be really large, tool support for assisting the developer in the exploration of alternative materializations is of great help. In previous research, we developed a prototype for generating quality-preserving implementations of software architectures, using pre-compiled knowledge about architectural styles and frameworks. In this paper, we present a more flexible approach, called SAME, which focuses on the architectural connectors as the pillars for the materialization process. The SAME design assistant applies a case-based reasoning (CBR) metaphor to deal with connector-related materialization experiences and quality attributes. The CBR engine is able to recall and adapt past experiences to solve new materialization problems; thus SAME can take advantage of developers' knowledge. Preliminary experiments have shown that this approach can improve the exploration of object-oriented solutions that are still faithful to the architectural prescriptions. [source] Electrocatalytic Oxidation of NADH by Oxidized s-Adenosyl-L-Methionine (SAMe): Application to NADH and SAMe DeterminationsELECTROANALYSIS, Issue 11 2004Noemí de-los-Santos-Álvarez Abstract s -Adenosyl- L -methionine (SAMe) is an adenosine analogue with therapeutical activity against affective disorders and liver dysfunctions. It can be oxidized on graphite electrode yielding a strongly adsorbed electroactive oxidation product for which a quinone-imine structure is proposed. This compound is capable of electrocatalyzing the NADH oxidation at low potentials, lowering the overvoltage by about 300,mV. An amperometric method for NADH determination at +0.1,V (Ag|AgCl|KClsat) is developed using an oxidized-SAMe-modified electrode in pH,9. Linear calibration plots were obtained with a detection limit of 2.4,nM. The electrode response time and the relative standard deviation of the slope of the calibration plot for 5 different modified electrodes were 12,s and 5.6% respectively. The catalytic scheme also provides the first method to determine SAMe itself by adsorptive differential pulse voltammetry. The linear range was found to be 42.4,424,nM with a reproducibility of 6.9%. The method was applied to SAMe determination in a pharmaceutical formulation. [source] Induction of avian musculoaponeurotic fibrosarcoma proteins by toxic bile acid inhibits expression of glutathione synthetic enzymes and contributes to cholestatic liver injury in mice,HEPATOLOGY, Issue 4 2010Heping Yang We previously showed that hepatic expression of glutathione (GSH) synthetic enzymes and GSH levels fell 2 weeks after bile duct ligation (BDL) in mice. This correlated with a switch in nuclear anti-oxidant response element (ARE) binding activity from nuclear factor erythroid 2,related factor 2 (Nrf2) to c,avian musculoaponeurotic fibrosarcoma (c-Maf)/V-maf musculoaponeurotic fibrosarcoma oncogene homolog G (MafG). Our current aims were to examine whether the switch in ARE binding activity from Nrf2 to Mafs is responsible for decreased expression of GSH synthetic enzymes and the outcome of blocking this switch. Huh7 cells treated with lithocholic acid (LCA) exhibited a similar pattern of change in GSH synthetic enzyme expression as BDL mice. Nuclear protein levels of Nrf2 fell at 20 hours after LCA treatment, whereas c-Maf and MafG remained persistently induced. These changes translated to ARE nuclear binding activity. Knockdown of c-Maf or MafG individually blunted the LCA-induced decrease in Nrf2 ARE binding and increased ARE-dependent promoter activity, whereas combined knockdown was more effective. Knockdown of c-Maf or MafG individually increased the expression of GSH synthetic enzymes and raised GSH levels, and combined knockdown exerted an additive effect. Ursodeoxycholic acid (UDCA) or S-adenosylmethionine (SAMe) prevented the LCA-induced decrease in expression of GSH synthetic enzymes and promoter activity and prevented the increase in MafG and c-Maf levels. In vivo knockdown of the Maf genes protected against the decrease in GSH enzyme expression, GSH level, and liver injury after BDL. Conclusion: Toxic bile acid induces a switch from Nrf2 to c-Maf/MafG ARE nuclear binding, which leads to decreased expression of GSH synthetic enzymes and GSH levels and contributes to liver injury during BDL. UDCA and SAMe treatment targets this switch. (HEPATOLOGY 2010.) [source] Understanding and Treating Patients With Alcoholic Cirrhosis: An UpdateALCOHOLISM, Issue 7 2009Giovanni Addolorato Alcoholic cirrhosis represents the terminal stage of alcoholic liver disease (ALD) and one of the main causes of death among alcohol abusers. The aim of this review was to provide an update on alcoholic cirrhosis, with an emphasis on recent findings. Increased alcohol consumption in developing countries is expected to increase cirrhosis mortality. There is a need, therefore, to develop new approaches to the prevention of ALD, including more attention to co-factors that may increase risk of ALD (i.e., obesity and diabetes, chronic HCV infection, and smoking). Furthermore, a better understanding of the pathological mechanisms on the basis of alcohol cirrhosis represents a cornerstone in order to develop new pharmacological treatments. Inflammatory and immune responses along with oxidative stress and alterations in adipokine secretion might contribute in different ways to the evolution of alcohol-induced fibrosis/cirrhosis. As of this date, patients with severe alcoholic hepatitis with a Maddrey Discriminant Factor (MDF) 32 should be offered pentoxifylline and/or corticosteroids unless contraindications exist. For ambulatory patients, S-adenosylmethionine (SAMe) may be considered in a motivated patient with nutritional support. Current studies do not support use of anti-tumor necrosis factor (TNF)-alpha antibody. Finally, achieving total alcohol abstinence should represent the main aim in the management of patients affected by any stage of cirrhosis. In the last decades, several drugs able to increase abstinence and prevent alcohol relapse have been evaluated and some of them have obtained approval for alcohol dependence. Patients with alcoholic cirrhosis; however, are usually excluded from such treatments. A recent study demonstrated the efficacy and safety of baclofen in inducing and maintaining alcohol abstinence in cirrhotic alcohol-dependent patients with cirrhosis. All together the information available suggests the need of a multimodal approach in the clinical management of these patients. [source] MYELINATION DEFICIT IN NERVE OF SUCKLING RATS DUE TO CYCLOLEUCINE -INDUCED DEFICIENCY OF METHYL DONORSJOURNAL OF THE PERIPHERAL NERVOUS SYSTEM, Issue 1 2000R. Bianchi We used cycloleucine (CL) , which prevents methionine conversion to S-adenosyl-methionine (SAMe) by inhibiting ATP-L-methionine-adenosyl-transferase (MAT) , to characterize the lipid and protein changes induced by methyl donors deficit in peripheral nerve and brain myelin in rats during development. We have previously shown that CL (400 mg/kg ip) given to suckling rats at days 7, 8, 12, and 13 after birth reduced brain and sciatic nerve weight gain, brain myelin content, protein, phospholipid (PL), and galactolipid concentration in comparison to control. Among PLs, only sphingomyelin (SPH) significantly increased by 35,50%. SAMe p-toluensulphonate (SAMe-SD4) (100 mg/kg, ip) given daily from day 7, as with exogenous SAMe, partially prevented some lipid alterations induced by CL, particularly galactolipid and SPH. To test the ability of CL to affect PL metabolism we have measured de novo PL biosynthesis, ex vivo in nerve homogenates (in comparison with brain homogenates) from control and CL-treated animals killed at day 18 after birth, starting from labelled substrates ([3H]-choline, specific activity 20 mCi/mmol) in a Tris/HCl buffer, containing 5 mM MgCl2, 0.2 mM EDTA, 0.1 mM ATP, and 0.5 mM of the labelled substrates. After 60 min incubation, lipids were extracted, PL separated by TLC, and corresponding silica gel fractions scraped and counted in a liquid scintillator. Phosphatidylcholine enrichment in labelled choline resulted in slight increases in brain and sciatic nerve of CL-treated rats, suggesting an increased synthesis rate via the Kennedy pathway, possibly due to the reduced availability of methyl donors. Interestingly, choline incorporation into SPH in brain and nerve myelin resulted in significant increases of 30,40%. In agreement with the observed decrease of galactolipid content and the relative increase in SPH, these data suggest an alteration in sphingolipid metabolism after CL. Among proteins, in sciatic nerves of CL-treated pups the relative content of a number of polypeptides, namely the 116, 90, 66, 58, and 56 kDa bands, decreased, whereas others increased; the most abundant PNS protein, protein zero, remained unchanged. The analyses of myelin basic protein isoforms revealed a dramatic increase in the 14.0 and 18.5 forms, indicating early active myelination. SAMe-SD4 treatment counteracted, and in some cases normalized, these changes. In summary, methyl donor deficiency induced by MAT inhibition produces myelin lipid and protein alterations, partly counteracted by SAMe-SD4 administration. The financial support of Telethon-Italy (grant No. D 51) is gratefully acknowledged. [source] The Task Remains the SameCONSERVATION BIOLOGY, Issue 1 2010Erica Fleishman No abstract is available for this article. [source] Meet the New Paul, Same as the Old Paul: Michael Wychograd, Kendall Soulen, and the New Problem of SupersessionismCROSSCURRENTS, Issue 2 2009William Plevan First page of article [source] Social and Commercial Entrepreneurship: Same, Different, or Both?ENTREPRENEURSHIP THEORY AND PRACTICE, Issue 1 2006James Austin Entrepreneurship has been the engine propelling much of the growth of the business sector as well as a driving force behind the rapid expansion of the social sector. This article offers a comparative analysis of commercial and social entrepreneurship using a prevailing analytical model from commercial entrepreneurship. The analysis highlights key similarities and differences between these two forms of entrepreneurship and presents a framework on how to approach the social entrepreneurial process more systematically and effectively. We explore the implications of this analysis of social entrepreneurship for both practitioners and researchers. [source] Tracking ,Same,Sex Love' from Antiquity to the Present in South AsiaGENDER & HISTORY, Issue 1 2002Rosemary Marangoly George This essay focuses on the anthology Same,Sex Love in India: Readings from Literature and History (2000), edited by Ruth Vanita and Saleem Kidwai. Unlike many other recently published, celebratory ,gay anthologies', this book contributes to ongoing scholarly work on specific same,sex erotic practices and relations in historical and cultural context. We examine issues relevant to this anthology and other such projects: the use of ,love' and ,same,sex' as (stable) signifiers over centuries; the validity of interpreting social reality through literary texts from the period; the difficulties of locating ,love' in severely hierarchical, even slave,owning, societies; and the implications of using such anthologies in the classroom. [source] Almotriptan Efficacy in Migraine With Developing Allodynia Is as High as the Efficacy in Migraine Without Allodynia , But Is It the Same in Migraine With Established Allodynia?HEADACHE, Issue 3 2009Rami Burstein PhD No abstract is available for this article. [source] Rethinking social work ethics: what is the real question?INTERNATIONAL JOURNAL OF SOCIAL WELFARE, Issue 2 2010Against difference, Responding to Stephen Webb's, diversity in social work' Jose J. Rethinking social work ethics: what is the real question? Responding to Stephen Webb's ,Against difference and diversity in social work' Int J Soc Welfare 2010: 19: 246,252 © 2009 The Author(s), Journal compilation © 2009 Blackwell Publishing Ltd and the International Journal of Social Welfare. In his recent article, Stephen Webb argued that the real question for social work ethics concerns ,recognising the Same and of restoring the principles of equality and social justice'. This argument also included raising questions about what should be considered an appropriate philosophical basis for progressive social work ethics. In his view, social work's emancipatory potential has been blunted by overstated and philosophically ill-informed human rights claims about difference and diversity. He suggested that French philosopher Alain Badiou offers social workers a ,set of conceptual devices for rethinking social work ethics'. I argue that pressing his points into Badiou's philosophical mould is unlikely to lead to a progressive social work practice, let alone solve the issues identified by Webb. Badiou's philosophical pronouncements about ethics are of questionable value and offer little or no assistance to social workers seeking to establish an ethical grounding for their professional practice. [source] The More Things Change, the More They Remain the SameJOURNAL OF CLINICAL HYPERTENSION, Issue 4 2009Marvin Moser MD First page of article [source] Staging of Hypertension and Total Cardiovascular Risk Assessment: Related but Not the Same,Challenge for the Hypertension SpecialistJOURNAL OF CLINICAL HYPERTENSION, Issue 11 2008Thomas D. Giles MD No abstract is available for this article. [source] Bullying and victimisation in Scottish secondary schools: Same or separate entities?AGGRESSIVE BEHAVIOR, Issue 1 2002A. Karatzias Abstract Previous research has suggested that bullying is an increasingly severe problem in schools. Such research has approached the phenomenon from two different angles. Earlier research has treated bullying and victimisation as separate entities. However, current research suggests that bullies and victims engage in a special dynamic and interactive relationship, thereby providing the need for studying any similarities and differences between bullies and victims in relation to various factors. The present research has approached bullying and victimisation in both ways. First, we studied differences between bullies, victims, and those not involved in relation to various demographic, school, well-being, and personality factors to identify factors that separate these three groups. In addition, we studied differences between those involved in bullying/victimisation (one group) and those never involved in relation to the same aforementioned factors to highlight aspects of the development of their special relationship (i.e., common factors). Prevalence rates and types of bullying/victimisation experienced/expressed in Scottish schools were also investigated. It was found that bullying and victimisation, when treated as separate entities, differed in relation to peer self-esteem, with bullies reporting higher levels of peer self-esteem than victims. When bullies and victims were treated as one group (involved), they were found to differ from the noninvolved group in relation to various factors, including school, well-being, and personality factors. The involved group was found to be disadvantaged in relation to all measures used. However, overall results indicated that from all these factors the best predictors of overall involvement as bully, victim, or bully-victim were Quality of School Life and school stress. The present results support the notion that bullying and victimisation could be treated, by future research, as both separate and/or interactive entities. This is so because bullying and victimisation were found to differ in relation to one personality factor, that is, peer self-esteem. However, Quality of School Life and school stress, both school factors, were found to be associated with the phenomenon as a whole. Results are discussed in relation to future development of antibullying policy in Scottish schools.Aggr. Behav. 28:45,61, 2002. © 2002 Wiley-Liss, Inc. [source] Views of Intimate Partner Violence in Same- and Opposite-Sex RelationshipsJOURNAL OF MARRIAGE AND FAMILY, Issue 2 2009Susan B. Sorenson Attitudes toward same-sex intimate relationships and intimate partner violence (IPV) are changing. Little research, however, has examined norms about IPV in same-sex relationships. Using a fractional factorial (experimental vignette) design, we conducted random-digit-dialed interviews in four languages with 3,679 community-residing adults. Multivariate analyses of responses to 14,734 vignettes suggest that IPV against gay male, lesbian, and heterosexual women is more likely than that against heterosexual men to be considered illegal and that it should be illegal, police called, and a stay-away order issued. Regardless of gender and sexual orientation, the type of abuse and whether a weapon was displayed are the strongest predictors of respondents' judgments about whether a behavior is illegal and merits a range of societal interventions. [source] Change and Continuity in German Landscapes of Fear and Imperialism after September 11th: "Nothing Remains" Equals; "More of the Same"?ANTIPODE, Issue 5 2002Bernd Belina First page of article [source] Is Globalization Making Us All the Same?BRITISH JOURNAL OF INDUSTRIAL RELATIONS, Issue 4 2005Frank Dobbin First page of article [source] The More Things Change the More They Stay the Same?BRITISH JOURNAL OF SPECIAL EDUCATION, Issue 4 2002A Response to the Audit Commission's Report on Statutory Assessment, Statements of SEN This article provides a response to some of the issues raised by Anne Pinney's summary, published in the September issue of BJSE, of the Audit Commission's report on statutory assessment and Statements of Special Educational Needs. In developing her critique, Lani Florian, lecturer in special and inclusive education at the University of Cambridge Faculty of Education and Editor of the Journal of Research in Special Educational Needs, asks a series of important and challenging questions. Can the broad notion of ,special educational needs' complement ideas about ,areas of need' or ,categories of handicap' and enable young people with severe, complex or long,term disabilities to have their needs met? Is SEN funding fairly distributed, among pupils with special educational needs in particular and across the education system in general? Should the relationship between the processes of formative and statutory assessment and Statements of Special Educational Needs be reconceptualised? Can the protection offered by the Statement be maintained in association with the development of good inclusive practices? And if there is to be a move away from provision designed to address children's individual difficulties, what forms of thinking, procedure and practice will enable staff to develop new ways of meeting the needs of all learners? I hope that the questions raised by this article will stimulate other commentators to contribute to the debate about our responses to special educational needs in the pages of BJSE [source] Has the guest arrived yet?BUSINESS ETHICS: A EUROPEAN REVIEW, Issue 3 2007Emmanuel Levinas, a stranger in business ethics To what extent can business ethics be ,hospitable' to Levinasian ethics? This paper raises questions about how business ethics relates to its guests, in this case the guest called ,Levinas'; the idea of introducing or inviting the work of an author into a field, as its guest, is by no means a simple problem of transference. For Jacques Derrida, there is hospitality only when the stranger's introduction to our home is totally unconditional. Such a conceptualisation of hospitality becomes even more demanding when the ,stranger' that is near our ,home' is an ethics also demanding hospitality, such as the ethics proposed by Levinas. An invitation puts in place particular circumstances that allow only for an arrival of the one invited. These conditions precede the so-called stranger, thereby predetermining the route to be taken, the destination to be reached and the correct manner of self-presentation. An invitation already reduces the Other to that which is expected by the inviter, that is to the Same. The hospitality of the field of business ethics becomes an endorsement of a particular version of the stranger, therefore recognisable by the field. Perhaps conceptualising Levinasian ethics as an ethics that cannot be invited might protect it from procedures that reduce the ,strangeness' of the stranger, making it knowable. That is the argument presented in this paper. [source] Guanidinium Alkynesulfonates with Single-Layer Stacking Motif: Interlayer Hydrogen Bonding Between Sulfonate Anions Changes the Orientation of the Organosulfonate R Group from "Alternate Side" to "Same Side"CHEMISTRY - A EUROPEAN JOURNAL, Issue 8 2010Karim Bouchmella Abstract Hydrolyses of HCCSO3SiMe3 (1) and CH3CCSO3SiMe3 (2) lead to the formation of acetylenic sulfonic acids HCCSO3H,2.33,H2O (3) and CH3CCSO3H,1.88,H2O (4). These acids were reacted with guanidinium carbonate to yield [+C(NH2)3][HCCSO3,] (5) and [+C(NH2)3][CH3CCSO3,] (6). Compounds 1,6 were characterized by spectroscopic methods, and the X-ray crystal structures of the guanidinium salts were determined. The X-ray results of 5 show that the guanidinium cations and organosulfonate anions associate into 1D ribbons through (8) dimer interactions, whereas association of these ions in 6 is achieved through (8) and (6) interactions. The ribbons in 5 associate into 2D sheets through (8) dimer interactions and (12) rings, whereas those in 6 are connected through (6) and (8) dimer interactions and (14) rings. Compound 6 exhibits a single-layer stacking motif similar to that found in guanidinium alkane- and arenesulfonates, that is, the alkynyl groups alternate orientation from one ribbon to the next. The stacking motif in 5 is also single-layer, but due to interlayer hydrogen bonding between sulfonate anions, the alkynyl groups of each sheet all point to the same side of the sheet. [source] Development of a web-based integrated manufacturing laboratoryCOMPUTER APPLICATIONS IN ENGINEERING EDUCATION, Issue 4 2001Samuel H. Huang Abstract The internet is dramatically changing the ways we learn and teach, as well as the way we interact as a society. The "same time, same place, only some people" traditional instructional method is giving way to "anytime, anyplace, anybody" educational models. This paper deals with the development of a Web-based integrated manufacturing laboratory (WIML), which represents a virtual mini-manufacturing corporation, whose aim is to support core manufacturing curriculum and to provide students with hands-on experience on various manufacturing functions and effective use of manufacturing software tools. Key components of the WIML include a manufacturing tutor, a data repository, message boards, customization pages, and links to the world-wide web. The WIML not only can stimulate students' interest in related manufacturing courses but also allow them to strengthen their computer skills and develop ability to work as a team. © 2002 Wiley Periodicals, Inc. Comput Appl Eng Educ 9: 228,237, 2001; Published online in Wiley InterScience (www.interscience.wiley.com.); DOI 10.1002/cae.10006 [source] Time-Dependent Discrete Network Design Frameworks Considering Land UseCOMPUTER-AIDED CIVIL AND INFRASTRUCTURE ENGINEERING, Issue 6 2010W. Y. Szeto Unlike existing models, the optimization frameworks can determine the optimal designs automatically without trial-and-error once the objective(s) is/are clearly defined. Moreover, these frameworks allow the evaluation of the impacts of the optimal designs on the related parties including landowners, toll road operators, transit operators, and road users, and help network planners and profit-makers with decision making by eliminating many alternative designs. A numerical study is set up to examine road network design's effects on these related parties under three road construction schemes: exact cost recovery, build-operate-transfer, and cross-subsidization. The results show that the changes in landowner profits are not the same after implementing any scheme. These unequal changes raise the issue of the landowner equity. This implies that the government has to consider trade-offs between parties' objectives carefully. [source] Development of olfactory epithelium in the human fetus: Scanning electron microscopic observationsCONGENITAL ANOMALIES, Issue 3 2009Mitsuhiro Kimura ABSTRACT Aims:, Human olfactory epithelium becomes functional at birth, but prenatal development remains unclear. In the present study, we aimed to clarify the development of human olfactory epithelium using scanning electron microscopy (SEM). Methods:, The development of human olfactory epithelium was observed in 24 externally normal fetuses, which were formalin-fixed and long-preserved, with a crown-rump length (CRL) of 102,336 mm (gestational week 14,38). The olfactory mucosa in the superior wall of the nasal septum near the choana were dissected and observed under SEM. We examined the number of olfactory vesicles per unit area, diameter of olfactory vesicles, and number and length of cilia on olfactory vesicles. Results:, At circa (ca) CRL 100 mm (ca 14 weeks), olfactory epithelium displayed several olfactory vesicles with 1,2 short cilia per unit area. At ca CRL 150 mm (ca 18 weeks), olfactory vesicles were present in small clusters, and cilia were longer. At CRL lager than 225 mm (ca 26 weeks), olfactory vesicles became located separately from each other, while length and number of cilia per olfactory vesicle were further increased. Conclusion:, The present findings suggest that fetal olfactory epithelium becomes morphologically almost the same as that in adults in late gestation, much later than previously thought. [source] The Aquatic Conservation Strategy of the Northwest Forest PlanCONSERVATION BIOLOGY, Issue 2 2006GORDON H. REEVES gestión de ecosistemas; gestión ribereña; modelos de soporte de decisiones; terrenos públicos Abstract:,Implemented in 1994, the Aquatic Conservation Strategy of the Northwest Forest Plan was designed to restore and maintain ecological processes for aquatic and riparian area conservation on federal lands in the western portion of the Pacific Northwest. We used decision support models to quantitatively evaluate changes in the condition of selected watersheds. In the approximately 10 years since strategy implementation, watershed condition scores changed modestly, but conditions improved in 64% of 250 sampled watersheds, declined in 28%, and remained relatively the same in 7%. Watersheds that had the largest declines included some where wildfires burned 30,60% of their area. The overall statistical distribution of the condition scores did not change significantly, however. Much of the increase in watershed condition was related to improved riparian conditions. The number of large trees (>51 cm diameter at breast height) increased 2,4%, and there were substantial reductions in tree harvest and other disturbances along streams. Whether such changes will translate into longer-term improvements in aquatic ecosystems across broader landscapes remains to be seen. Resumen:,Implementada en 1994, la Estrategia de Conservación Acuática del Plan Forestal del Noroeste fue diseñada para restaurar y mantener procesos ecológicos para la conservación de áreas acuáticas y ribereñas en terrenos federales en la porción occidental del Pacífico Noroeste (E.U.A.). Utilizamos modelos de soporte de decisiones para evaluar cuantitativamente los cambios en la condición de cuencas seleccionadas. En los casi 10 años desde la implementación de la estrategia, los valores de la condición de las cuencas cambiaron someramente, pero las condiciones mejoraron en 64% de las 250 cuencas muestreadas, declinaron en 28% y permanecieron relativamente iguales en 7%. Las cuencas con las mayores declinaciones incluyeron algunas en las que 30-60% de su superficie fue quemada por fuegos sin control. Sin embargo, la distribución espacial total de los valores no cambió significativamente. Buena parte del incremento en las condiciones de la cuenca se relacionó con el mejoramiento de las condiciones ribereñas. El número de árboles grandes (>51 cm diámetro a la altura del pecho) aumentó 2-4%, y hubo reducciones sustanciales en la cosecha de árboles y otras perturbaciones a lo largo de arroyos. Aun habrá que ver si tales cambios se traducirán en mejoramientos a largo plazo en los ecosistemas acuáticos en paisajes más extensos. [source] Forest Stand Dynamics and Livestock Grazing in Historical ContextCONSERVATION BIOLOGY, Issue 5 2005MICHAEL M. BORMAN clima; incendio forestal; pastoreo histórico; pino ponderosa; supresión de fuego Abstract:,Livestock grazing has been implicated as a cause of the unhealthy condition of ponderosa pine forest stands in the western United States. An evaluation of livestock grazing impacts on natural resources requires an understanding of the context in which grazing occurred. Context should include timing of grazing, duration of grazing, intensity of grazing, and species of grazing animal. Historical context, when and under what circumstances grazing occurred, is also an important consideration. Many of the dense ponderosa pine forests and less-than-desirable forest health conditions of today originated in the early 1900s. Contributing to that condition was a convergence of fire, climate, and grazing factors that were unique to that time. During that time period, substantially fewer low-intensity ground fires (those that thinned dense stands of younger trees) were the result of reduced fine fuels (grazing), a substantial reduction in fires initiated by Native Americans, and effective fire-suppression programs. Especially favorable climate years for tree reproduction occurred during the early 1900s. Exceptionally heavy, unregulated, unmanaged grazing by very large numbers of horses, cattle, and sheep during the late nineteenth and early twentieth centuries occurred in most of the U.S. West and beginning earlier in portions of the Southwest. Today, livestock numbers on public lands are substantially lower than they were during this time and grazing is generally managed. Grazing then and grazing now are not the same. Resumen:,El pastoreo de ganado ha sido implicado como una causa de la mala salud de los bosques de pino ponderosa en el occidente de Estados Unidos. La evaluación de los impactos del pastoreo sobre los recursos naturales requiere de conocimiento del contexto en que ocurrió el pastoreo. El contexto debe incluir al período de ocurrencia, la duración y la intensidad del pastoreo, así como la especie de animal que pastoreó. El contexto histórico, cuando y bajo que circunstancias ocurrió el pastoreo, también es una consideración importante. Muchos de los bosques densos de pino ponderosa y de las condiciones, menos que deseables, de salud de los bosques actuales se originaron al principio del siglo pasado. Contribuyó a esa condición una convergencia de factores, fuego, clima y pastoreo, que fueron únicos en ese tiempo. Durante ese período, hubo sustancialmente menos incendios superficiales de baja intensidad (que afectaron a grupos densos de árboles más jóvenes) como resultado de la reducción de combustibles finos (pastoreo), una reducción sustancial en los incendios iniciados por Americanos Nativos y programas efectivos de supresión de incendios. Al inicio del siglo pasado hubo años con clima especialmente favorable para la reproducción de árboles. Al final del siglo diecinueve y comienzo del veinte hubo pastoreo no regulado ni manejado, excepcionalmente intensivo, por una gran cantidad de caballos, reses y ovejas en la mayor parte del oeste de E.U.A. y aun antes en porciones del suroeste. En la actualidad, el número de semovientes en terrenos públicos es sustancialmente menor al de ese tiempo, y el pastoreo generalmente es manejado. El pastoreo entonces y el pastoreo ahora no son lo mismo. [source] Patterns of Nest Predation on Artificial and Natural Nests in ForestsCONSERVATION BIOLOGY, Issue 2 2004DAWN M. BURKE ave de bosque; depredación de nidos; éxito de nidos; experimento de nidos artificiales; nidos naturales Abstract:,Artificial nest experiments have been used in an attempt to understand patterns of predation affecting natural nests. A growing body of literature suggests that neither relative rates nor patterns of predation are the same for artificial and natural nests. We studied nest predation and daily mortality rates and patterns at real and artificial ground and shrub nests to test the validity of artificial nest experiments. We monitored 1667 artificial and 344 natural nests, over seven trials, in three regions, across 58 sites in Ontario. We controlled for many of the factors thought to be responsible for previously reported differences between predation rates on natural and artificial nests. Although artificial nests in our study resembled natural nests, contained eggs of appropriate size, shape, and color of target bird species, and were placed in similar microhabitats as natural nests, the rates of predation on these nests did not parallel rates on natural nests for any region in terms of absolute rate or pattern. Predation rates on artificial nests did not vary between years, as they tended to for natural nests, and the magnitude of predation pressure on artificial ground nests compared with shrub nests did not show the same pattern as that on natural nests. In general, rates of predation on artificial nests were significantly higher than on natural nests. Our results suggest that conclusions derived from artificial nest studies may be unfounded. Given that many influential ideas in predation theory are based on results of artificial nest experiments, it may be time to redo these experiments with natural nests. Resumen:,Se han utilizado experimentos con nidos artificiales con la intención de entender los patrones de depredación que afectan a los nidos naturales. La bibliografía sugiere que ni las tasas relativas ni los patrones de depredación son iguales para nidos artificiales y naturales. Estudiamos las tasas y patrones de depredación de nidos y de mortalidad diaria en nidos reales y artificiales sobre el suelo y en matorrales para probar la validez de los experimentos con nidos artificiales. Monitoreamos 1667 nidos artificiales y 344 nidos naturales, en siete pruebas, en tres regiones, en 58 sitios en Notario. Controlamos muchos de los factores que se piensa son responsables de diferencias entre tasas de depredación en nidos naturales y artificiales reportadas previamente. Aunque los nidos artificiales en nuestro estudio se asemejaron a nidos naturales, contenían huevos de tamaño, forma y color adecuados para la especie de ave y fueron colocados en microhábitats similares a los de nidos naturales, las tasas de depredación en estos nidos no fueron similares a las tasas en nidos naturales en ninguna región en términos de tasa o patrón absoluto. Las tasas de depredación en nidos artificiales no variaron de un año a otro, como fue la tendencia en nidos naturales, y la magnitud de la presión de depredación en nidos sobre el suelo comparada con nidos en arbustos no mostró el mismo patrón que la depredación en nidos naturales. Nuestros resultados sugieren que las conclusiones derivadas de estudios con nidos artificiales pueden ser infundadas. Debido a que muchas ideas influyentes en la teoría de la depredación se basan en los resultados de experimentos con nidos artificiales, puede haber llegado el momento de volver a realizar estos experimentos utilizando nidos naturales. [source] Evaluation of the skin sensitizing potency of chemicals by using the existing methods and considerations of relevance for elicitationCONTACT DERMATITIS, Issue 1 2005David A. Basketter The Technical Committee of Classification and Labelling dealing with harmonized classification of substances and classification criteria under Directive 67/548/EEC on behalf of the European Commission nominated an expert group on skin sensitization in order to investigate further the possibility for potency consideration of skin sensitizers for future development of the classification criteria. All substances and preparations should be classified on the basis of their intrinsic properties and should be labelled accordingly with the rules set up in the Directive 67/548/EEC. The classification should be the same under their full life cycle and in the case that there is no harmonized classification the substance or preparation should be self-classified by the manufacturer in accordance with the same criteria. The Directive does not apply to certain preparations in the finished state, such as medical products, cosmetics, food and feeding stuffs, which are subject to specific community legislation. The main questions that are answered in this report are whether it would be possible to give detailed guidance on how to grade allergen potency based on the existing methods, whether such grading could be translated into practical thresholds and whether these could be set for both induction and elicitation. Examples are given for substances falling into various potency groups for skin sensitization relating to results from the local lymph node assay, the guinea pig maximization test, the Buehler method and human experience. [source] Lowered albumin extravasation rate in heart but not in other organs in ,3-integrin-deficient miceACTA PHYSIOLOGICA, Issue 4 2009Ø. S. Svendsen Abstract Aim:, The vascular protein permeability is dependent on the integrity of the vascular wall. The heart capillaries in male mice lacking ,3 integrins have an immature phenotype. Previously, we have demonstrated a role for ,v,3 integrins in control of interstitial fluid pressure (Pif) and thereby in the fluid flux during inflammation. We wanted to explore a possible role for ,v,3 integrins in controlling capillary protein permeability during control situation and inflammation. Methods:, We performed double-tracer and microdialysis experiments on ,3-integrin-deficient mice and wild type control mice. We also measured blood pressure and heart rate in the two mice strains. Results:, We found reduced albumin extravasation (during 25 min) in the heart capillaries (0.053 ± 0.003 vs. 0.087 ± 0.009 mL g,1 dw, P < 0.05), and an increased cardiac mass/body weight (5.3 × 10,3 ± 0.3 × 10,3 vs. 3.8 × 10,3 ± 0.1 × 10,3, P < 0.01) in the ,3-integrin-deficient mice (n = 6) compared with the controls (n = 6). Heart rate and blood pressure were the same in mice with and without ,3-integrins. No difference in permeability was found in other tissues studied, or under local inflammation. Conclusion:, These results show a function for the ,v,3 integrin in the regulation of protein permeability, selective for the heart capillaries. [source] P72 Pigmented patch-test substance and laser Doppler perfusion imagingCONTACT DERMATITIS, Issue 3 2004Bolli Bjarnason Objective:, To investigate if pigment of a dark patch-test substance may affect assessment of perfusion with the laser Doppler imaging technique. Materials:, 13 subjects who previously patch-tested positive with 25% balsam of Peru in petrolatum were re-tested with the same test substance and petrolatum controls applied directly by transparent foils and with much weaker and less pigmented serial doses tested with polyester squares. Readings of perfusion were performed through the test substances and the transparent foils at time intervals up to 4 days while tests were applied and for 5 days following detachment of tests. The instrument set-up of the LDPI was the same as we have suggested for non-pigmented patch-test substances tested on white skin. Results:, Results show that pigment remnants following detachment of the dark pigmented and pasty test substance containing the petrolatum vehicle were prone to affect perfusion assessments by masking detection of perfusion of parts of test sites. A real masking effect is supported by a similar effect with readings of the same tests while they were applied and by no such observable effect with the petrolatum controls or the non-pasty and much less pigmented squares. Conclusion:, The results show that pigment of patch-test substances may affect perfusion assessments with the instrument set-up suggested for non-pigmented substances. [source] | ||||||||||||||||||||||||||||||||||||||||