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Selected AbstractsThe genome of Syntrophomonas wolfei: new insights into syntrophic metabolism and biohydrogen productionENVIRONMENTAL MICROBIOLOGY, Issue 8 2010Jessica R. Sieber Summary Syntrophomonas wolfei is a specialist, evolutionarily adapted for syntrophic growth with methanogens and other hydrogen- and/or formate-using microorganisms. This slow-growing anaerobe has three putative ribosome RNA operons, each of which has 16S rRNA and 23S rRNA genes of different length and multiple 5S rRNA genes. The genome also contains 10 RNA-directed, DNA polymerase genes. Genomic analysis shows that S. wolfei relies solely on the reduction of protons, bicarbonate or unsaturated fatty acids to re-oxidize reduced cofactors. Syntrophomonas wolfei lacks the genes needed for aerobic or anaerobic respiration and has an exceptionally limited ability to create ion gradients. An ATP synthase and a pyrophosphatase were the only systems detected capable of creating an ion gradient. Multiple homologues for ,-oxidation genes were present even though S. wolfei uses a limited range of fatty acids from four to eight carbons in length.Syntrophomonas wolfei, other syntrophic metabolizers with completed genomic sequences, and thermophilic anaerobes known to produce high molar ratios of hydrogen from glucose have genes to produce H2 from NADH by an electron bifurcation mechanism. Comparative genomic analysis also suggests that formate production from NADH may involve electron bifurcation. A membrane-bound, iron,sulfur oxidoreductase found in S. wolfei and Syntrophus aciditrophicus may be uniquely involved in reverse electron transport during syntrophic fatty acid metabolism. The genome sequence of S. wolfei reveals several core reactions that may be characteristic of syntrophic fatty acid metabolism and illustrates how biological systems produce hydrogen from thermodynamically difficult reactions. [source] Dynamic two state stochastic models for ecological regime shiftsENVIRONMETRICS, Issue 8 2009Jan Kloppenborg Møller Abstract A simple non-linear stochastic two state, discrete-time model is presented. The interaction between benthic and pelagic vegetation in aquatic ecosystems subject to changing external nutrient loading is described by the non-linear functions. The dynamical behavior of the deterministic part of the model illustrates that hysteresis effect and regime shifts can be obtained for a limited range of parameter values only. The effect of multiplicative noise components entering at different levels of the model is presented and discussed. Including noise leads to very different results on the stability of regimes, depending on how the noise propagates through the system. The dynamical properties of a system should therefore be described through propagation of the state distributions rather than the state means and consequently, stochastic models should be compared in a probabilistic framework. Copyright © 2008 John Wiley & Sons, Ltd. [source] Review of carrot fly control in Northern Europe , 2009,EPPO BULLETIN, Issue 2 2009R. Collier In February 2009, the European and Mediterranean Plant Protection Organization (EPPO) held a workshop to discuss the management of carrot fly (Psila rosae) within Europe. Prior to the workshop, participants completed a questionnaire about carrot fly and current control methods and some of the information is summarised in this paper. In general, this pest is controlled adequately at present, but there is a heavy reliance on insecticides. The responses to the questionnaire highlighted a number of issues, in particular: the limited range and efficacy of the insecticides available at present, concerns about the availability of effective control measures in the future and a need for improvements in the targeting of treatments through forecasting and monitoring and the use of treatment thresholds. [source] Theoretical and conceptual issues in time,place discriminationEUROPEAN JOURNAL OF NEUROSCIENCE, Issue 9 2009Jonathon D. Crystal Abstract The need to discover resources that are available under specific environmental constraints represents a fundamental environmental pressure on the evolution of behavior. Time,place discrimination refers to the ability to secure resources when they are available under specific temporal and spatial contingencies. This article reviews a number of examples of time,place discrimination. The review highlights theoretical and conceptual issues that are needed to behaviorally identify the mechanisms responsible for time,place performance. Next, limitations on time,place performance that may be imposed by a circadian system are described. Finally, a number of lines of research that broaden these limitations are discussed. These lines of research include studies that suggest that (i) a broad range of long intervals (outside the limited range of circadian entrainment) are timed, (ii) at least some long intervals (16,21 h) are timed with an endogenous self-sustaining oscillator, (iii) short intervals (in the range of 1,3 min) are timed with an endogenous self-sustaining oscillator, and (iv) memory for specific unique events (including when and where they occurred) is based on a circadian representation of time. It is concluded that a unified theory of timing that can retain the times of occurrence of individual events is needed. The time of occurrence of an event may be encoded not only with respect to a circadian oscillator but also with respect to other oscillators in the long-interval and short-interval ranges. [source] LINKING COEVOLUTIONARY HISTORY TO ECOLOGICAL PROCESS: DOVES AND LICEEVOLUTION, Issue 10 2003Dale H. Clayton Abstract Many host-specific parasites are restricted to a limited range of host species by ecological barriers that impede dispersal and successful establishment. In some cases, microevolutionary differentiation is apparent on top of host specificity, as evidenced by significant parasite population genetic structure among host populations. Ecological barriers responsible for specificity and genetic structure can, in principle, reinforce macroevolutionary processes that generate congruent host-parasite phylogenies. However, few studies have explored both the micro- and macroevolutionary ramifications of close association in a single host-parasite system. Here we compare the macroevolutionary histories of two genera of feather lice (Phthiraptera: Ischnocera) that both parasitize New World pigeons and doves (Aves: Columbiformes). Earlier work has shown that dove body lice (genus Physconelloides) are more host specific and have greater population genetic structure than dove wing lice (Columbicola). We reconstructed phylogenies for representatives of the two genera of lice and their hosts, using nuclear and mitochondrial DNA sequences. The phylogenies were well resolved and generally well supported. We compared the phylogenies of body lice and wing lice to the host phylogeny using reconciliation analyses. We found that dove body lice show strong evidence of cospeciation whereas dove wing lice do not. Although the ecology of body and wing lice is very similar, differences in their dispersal ability may underlie these joint differences in host specificity, population genetic structure, and coevolutionary history. [source] Using patch studies to link mesoscale patterns of feeding and growth in larval fish to environmental variabilityFISHERIES OCEANOGRAPHY, Issue 4 2002John F. Dower We present results from a series of three patch studies designed to examine links between environmental variability and mesoscale patterns of feeding and growth of larval radiated shanny (Ulvaria subbifurcata). We examine the effects of variability in temperature, turbulence and prey concentration on both the mean (i.e. population level) and the variance (i.e. individual level) of larval feeding and growth rates among the three bays. Although both gut fullness and growth rates differ significantly between bays, our results show only weak environmental influences. When larvae are pooled across bays (i.e. treated as independent observations), environmental factors generally explain <4% of the variability in gut fullness. When treated as daily mean residuals, however, temperature accounts for 41% of the variability in mean gut fullness, while both temperature and prey concentration also explain significant portions of the variance in gut fullness (38 and 43%, respectively). Between-bay differences in larval growth rates are consistent with patterns of temperature variation but not with patterns of prey availability. Studies relying on tracking a single patch of larvae typically suffer from having too few observations to detect significant relationships between feeding or growth and environmental variables. By following three patches we collected a larger number of observations. However, as we encountered only a limited range of environmental conditions it remains difficult to adequately assess the role of environmental factors. In part, this problem stems from the inability of fisheries oceanographers to track the recent environmental history of individual larvae on the same fine scales currently employed to collect biological data (e.g. guts and otoliths) on individuals. [source] Imagining the Future: Children, Education and Intergenerational Transmission of Poverty in Urban BangladeshIDS BULLETIN, Issue 1 2009Naila Kabeer Failure to invest in children's education is widely recognised as a key mechanism for the intergenerational transmission of poverty. At the same time, rising levels of education among different socioeconomic groups in countries like Bangladesh suggest that poverty on its own is not an adequate explanation for this failure. This article uses survey data on low-income households in urban Bangladesh to explore what differentiates parents who have managed to send their children to school from those who have not. One factor is education: parents with no education are more likely to have children of school-going age who are not at school. Different aspects of household vulnerability, as captured by asset deficits, reliance on casual labour and female headship, also play an important role in determining whether children go to school or not. In addition, the article argues that contextual factors have an important influence on how parents imagine their children's future and how children themselves regard education. The hazards of daily life in slum environments, the limited range of job opportunities available and the absence of decent educational facilities all serve to undermine parental commitment and children's motivation with regard to education. The article suggests that the state and civil society should collaborate to promote educational and livelihood interventions which are responsive to the needs of the more vulnerable sections of the poor and to reshape how parents and children envisage the future. [source] A finite volume method for large strain analysis of incompressible hyperelastic materialsINTERNATIONAL JOURNAL FOR NUMERICAL METHODS IN ENGINEERING, Issue 12 2005I. Bijelonja Abstract This paper describes development of a displacement,pressure based finite volume formulation for modelling of large strain problems involving incompressible hyperelastic materials. The method is based on the solution of the integral conservation equations governing momentum balance in total Lagrangian description. The incompressibility constraint is enforced by employing the integral form of the mass conservation equation in deformed configurations of the body. A Mooney,Rivlin incompressible material model is used for material description. A collocated variable arrangement is used and the spatial domain is discretized using finite volumes of an arbitrary polyhedral shape. A segregated approach is employed to solve resulting set of coupled non-linear algebraic equations, utilizing a SIMPLE based algorithm for displacement,pressure coupling. Comparisons of numerical and analytical results show a very good agreement. For the limited range of cell topologies tested the developed method appears to be locking free. Copyright © 2005 John Wiley & Sons, Ltd. [source] Development of a computerized assessment for visual maskingINTERNATIONAL JOURNAL OF METHODS IN PSYCHIATRIC RESEARCH, Issue 2 2002Michael Foster Green Abstract Visual masking provides a highly informative means of assessing the earliest stages of visual processing. This procedure is frequently used in psychopathology research, most commonly in the study of schizophrenia. Deficits in visual masking tasks appear to reflect vulnerability factors in schizophrenia, as opposed to the symptoms of the illness. Visual masking procedures are typically conducted on a tachistoscope, which limits standardization across sites, as well as the number of variables that can be examined in a testing session. Although visual masking can be administered on a computer, most methods used so far have had poor temporal resolution and yielded a limited range of variables. We describe the development of a computerized visual masking battery. This battery includes a staircase procedure to establish an individual's threshold for target detection, and a relatively dense sampling of masking intervals. It includes both forward and backward masking trials for three different masking conditions that have been used previously in experimental psychopathology (target location, target identification with high-energy mask, and target identification with low-energy mask). Copyright © 2002 Whurr Publishers Ltd. [source] Dollar Dominance, Euro Aspirations: Recipe for Discord?JCMS: JOURNAL OF COMMON MARKET STUDIES, Issue 4 2009BENJAMIN J. COHEN After nearly a century of dominance of the international monetary system, has the US dollar finally met its match in the euro? When Europe's economic and monetary union (EMU) came into existence in 1999, many observers predicted that the euro would soon join America's greenback at the peak of global finance. Achievements, however, have fallen short of aspiration. After an initial spurt of enthusiasm, international use of the euro actually appears now to be levelling off, even stalling, and so far seems confined largely to a limited range of market sectors and regions. The euro has successfully attained a place second only to the greenback , but it remains, and is likely to remain, a quite distant second without a determined effort by EMU authorities to promote their money's global role. The temptation will surely be great. In practical terms, it is difficult to imagine that EMU authorities will refrain entirely from trying to promote a greater role for the euro. But that, in turn, could turn out to be a recipe for discord with the United States, which has never made any secret of its commitment to preserving the greenback's worldwide dominance. A struggle for monetary leadership could become a source of sustained tensions in US,European relations. Fortunately, however, there seems relatively little risk of a destabilizing escalation into outright geopolitical conflict. [source] Reaching the covert, fragile side of patients: The case of narcissistic personality disorderJOURNAL OF CLINICAL PSYCHOLOGY, Issue 2 2007Giuseppe Nicolò A multifaceted self allows selection of those sides that are most suited to a situation and an interpersonal context, thus improving adaptation. Patients suffering from personality disorders display a limited range of self-aspects, and their relationships are stereotyped and maladaptive. Another problem is that some of these sides scarcely reach consciousness and usually remain in the background. In the case of narcissistic personality disorder (NPD) the self-part that is fragile is unlikely to reach consciousness, so that people suffering from this disorder are impervious and detached. We present a case of a psychotherapist working with a woman suffering from NPD by facilitating the emergence of the fragile part of her self, hidden by angry and scornful characters. We demonstrate, moreover, how reaching such a self-part is associated with an improvement in the patient's interpersonal relationships outside the consulting room. © 2007 Wiley Periodicals, Inc. J Clin Psychol: In Session 63: 141,152, 2007. [source] Nest-site selection by Common Black-Hawks in southwestern New MexicoJOURNAL OF FIELD ORNITHOLOGY, Issue 1 2008Giancarlo Sadoti ABSTRACT Despite the interest of resource managers and conservationists in the status of Common Black-Hawk (Buteogallus anthracinus) populations in the southwestern United States, little is known about their nesting success and habitat requirements. Because such information is essential for effective population and habitat management, I examined the nesting success and nest-site selection of Common Black-Hawks in southwestern New Mexico during 2000 and 2001. Of the 37 nesting attempts in 21 territories, ,1 young fledged from 25 nests (68%). Comparison of nest-sites and nonused sites suggested that breeding Common Black-Hawks selected nest-sites in areas with a sparser and shorter subcanopy tree layer and in trees with a smaller trunk diameter and a greater minimum crown diameter. These differences appear to be related to variation in forest ages within territories, with nonused sites having fewer, but older, canopy trees than nest-sites. Sites with younger, smaller subcanopy trees may provide forest structure for more effective foraging, whereas the characteristics of younger nest tree canopies may reduce the risk of nest predation or offer more protection from inclement weather. Due to the limited range of this species in the southwestern United States, efforts to encourage the establishment and maturation of riparian forests in Common Black-Hawk breeding areas could be important in sustaining available nesting habitat and, in turn, maintaining or expanding current population levels. SINOPSIS Aunque existe interés de parte de profesionales en manejo de recursos y conservacionistas en el estatus de las poblaciones de Buteogallus anthracinus en el sudoeste de los Estados Unidos, poco se conoce sobre su éxito de anidamiento y requerimientos de hábitat. Por la razón que esta información es esencial para el éxito del manejo poblacional y del hábitat para esta especie, examiné el éxito de anidamiento y la selección del lugar de anidamiento de Buteogallus anthracinus en el sudeste del estado de Nueva México durante el 2000 y el 2001. De los 37 intentos de anidamiento en 21 territorios, ,1 de los polluelos volaron de 25 nidos (68%). Una comparación entre lugares donde se ubicaban los nidos y sitios no utilizados para anidar indica que individuos seleccionaron lugares para anidar en áreas con una menor cobertura y una menor altura del sub-dosel. Adicionalmente, los nidos fueron ubicados en árboles con un menor diámetro del tronco y con un mayor diámetro mínimo de la corona. Estas diferencias parecen ser relacionadas a la variación en la edad del bosque dentro de los territorios, con sitios no utilizados caracterizados por un número menor de árboles del dosel pero las cuales tienen una edad mayor que los árboles del dosel en los sitios donde se ubicaron los nidos. Sitios con árboles en el sub-dosel de menor edad y de menor tamaño podrían proveer la estructura del bosque necesaria para un forrajeo mas efectivo, mientras que las características de las coronas de los árboles de menor edad en la cual se encuentra el nido podrían reducir el riesgo de la depredación del nido o proveer mas protección de mal tiempo. Dado el rango limitado de esta especie en el sudeste de los Estados Unidos, los esfuerzos para animar el establecimiento y la maduración de los bosques riparios en las áreas de anidamiento de esta especie podrían ser importantes para mantener el hábitat disponible para anidar y a la vez mantener o expandir los tamaños actuales de las poblaciones. [source] Lay food and health worker involvement in community nutrition and dietetics in England: roles, responsibilities and relationship with professionalsJOURNAL OF HUMAN NUTRITION & DIETETICS, Issue 3 2008L. A. Kennedy Abstract Background, Community-based food initiatives have developed in recent years with the aim of engaging previously ,hard to reach' groups. Lay workers engaged in community nutrition activities are promoted as a cost-effective mechanism for reaching underserved groups. The main objective of the study was to explore perceptions and definitions of lay food and health worker (LFHW) helping roles within the context of National Health Service (NHS) community nutrition and dietetic services in order to define the conceptual and practical elements of this new role and examine the interface with professional roles. Methods, Interpretive qualitative inquiry; semi-structured interviews with LFHW and NHS professionals employed by community-based programmes, serving ,hard-to-reach' neighbourhoods, across England. A total sampling framework was used to capture all existing and ,fully operational' lay food initiatives in England at the commencement of fieldwork (January 2002). Findings, In total, 29 professionals and 53 LFHWs were interviewed across 15 of the 18 projects identified. Although all 15 projects shared a universal goal, to promote healthy eating, this was achieved through a limited range of approaches, characterized by a narrow, individualistic focus. Lay roles spanned three broad areas: nutrition education; health promotion; and administration and personal development. Narratives from both professionals and LFHWs indicated that the primary role for LFHWs was to encourage dietary change by translating complex messages into credible and culturally appropriate advice. Conclusions, This research confirms the emerging discipline involving lay helping within the NHS and community dietetics. The primary role of LFHWs in the 15 projects involved was to support existing NHS services to promote healthy eating amongst ,hard to reach' communities. The activities undertaken by LFHWs are strongly influenced by professionals and the NHS. Inherent to this is a fairly narrow interpretation of health, resulting in a limited range of practice. [source] The characterization of fluidization behavior using a novel multichamber microscale fluid bedJOURNAL OF PHARMACEUTICAL SCIENCES, Issue 3 2004Eetu Räsänen Abstract In the preformulation stage, there is a special need to determine the process behavior of materials with smaller amounts of samples. The purpose of this study was to assemble a novel automated multichamber microscale fluid bed module with a process air control unit for the characterization of fluidization behavior in variable conditions. The results were evaluated on the basis of two common computational methods, the minimum fluidization velocity, and the Geldart classification. The materials studied were different particle sizes of glass beads, microcrystalline cellulose, and silicified microcrystalline cellulose. During processing, the different characteristic fluidization phases (e.g., plugging, bubbling, slugging, and turbulent fluidization) of the materials were observed by the pressure difference over the bed. When the moisture content of the process air was increased, the amount of free charge carriers increased and the fine glass beads fluidized on the limited range of velocity. The silicification was demonstrated to improve the fluidization behavior with two different particle sizes of cellulose powders. Due to the interparticle (e.g., electrostatic) forces of the fine solids, the utilization of the computational predictions was restricted. The presented setup is a novel approach for studying process behavior with only a few grams of materials. © 2004 Wiley-Liss, Inc. and the American Pharmacists Association J Pharm Sci 93: 780,791, 2004 [source] Middle-Class African American Parents' Conceptions of Parenting in Early AdolescenceJOURNAL OF RESEARCH ON ADOLESCENCE, Issue 2 2001Judith Smetana Conceptions of parenting were examined in 87 middle-class African American parents (87 mothers and 51 fathers) of early adolescents (M= 13.11 years of age). Using semistructured interviews, parents were queried about two developmentally salient issues of early adolescence: parental limit-setting and adolescent independence. Parents primarily defined firm limits in terms of nonnegotiation, strongly endorsed setting firm limits regarding a range of issues, and justified the importance of limits by focusing on adolescents' socialization and psychological development. Mothers rated limiting adolescents' behavior as more important than permitting or encouraging adolescents' independence. Limits were seen as more important by mothers of younger rather than older early adolescent females, but mothers encouraged independence more for younger rather than older early adolescent males. Mothers permitted independent decisions regarding a limited range of issues such as clothes and appearance, based on psychological concerns with adolescents' developing autonomy and competence; they encouraged independence primarily by encouraging greater responsibility. The results demonstrate that there is considerable heterogeneity in African American parents' beliefs and goals about parenting in early adolescence. [source] Effect of Yttrium and Erbium Ions on Epitaxial Phase Transformations in AluminaJOURNAL OF THE AMERICAN CERAMIC SOCIETY, Issue 4 2003Deirdre D. Ragan The effect of low concentrations of Y, Er, and Cr solutes on the amorphous-to-, transformation and on the ,-to-, transformation in aluminum oxide has been studied in situ by time-resolved reflectivity. The activation energies of the two transformations with these dopants are the same as in undoped alumina, being 4.1 ± 0.1 and 5.2 ± eV, respectively. Although not affecting the activation energies, Y, Er, and Cr do affect the transformation kinetics. Y and Cr ions decrease the ,-to-, transformation velocity and, over the limited range studied, do so in proportion to their concentration. Concentrations of Er as low as ,6 ppm retard the ,-to-, transformation and concentrations of 32 ppm essentially stop the transformation occurring within the times and temperatures accessible within the present experiment, thereby preventing quantification of the effect of Er on the ,-phase transformation. Erbium also retards the amorphous-to-, transformation relative to undoped alumina whereas yttrium and chromium accelerate it. [source] Population status and behaviours of the Samoan flying fox (Pteropus samoensis) on Tutuila Island, American SamoaJOURNAL OF ZOOLOGY, Issue 3 2001Anne P. Brooke Abstract The small population and limited range of the Samoan flying fox Pteropus samoensis has generated concern regarding the survival of this large, diurnally active bat. During 1995,96, surveys were conducted monthly in six study valleys on Tutuila Island, American Samoa, to assess population size. The amount of diurnal and nocturnal activity was investigated to gauge the accuracy of diurnal surveys, and territorial behaviours were observed to determine how they influenced local dispersion. Individuals showed long-term fidelity to a series of roosts and small core areas that were used both nocturnally and diurnally. Territorial defence was observed only of temporary feeding territories in fruiting or flowering trees. Bats defended food resources by aerial patrols and extended aerial chases in which intruders were frequently bitten. Foraging movements changed seasonally, with up to 80% of individuals observed bypassing study valleys. The mean density of bats observed within the study valleys was 6.1 bats/km2 (range = 0.9,18.5 bats/km2). Pteropus samoensis were active both nocturnally and diurnally with greatest activity in late afternoon and evening, 16:00,22:00. Because bats were most active at night, it is probable that daytime surveys of flying bats undercount the number of individuals present. Greatest densities were found in valleys that were contiguous with large tracts of forest inaccessible to people. Most observations of roosting bats were of solitary males on dead branches that jutted above the forest canopy, while females and dependant young roosted below the canopy, hidden within vegetation. Adult male,female pairs were rarely seen together other than during the mating period in August,January. The population has increased following a ban on hunting, but reliance on mature forest makes long-term species survival dependant on protection of the limited mature forest remaining and continued hunting restrictions. [source] The Court's Role in Promoting Comprehensive Justice for Pregnant Drug and Alcohol UsersJUVENILE AND FAMILY COURT JOURNAL, Issue 3 2008Tourine Johnstone ABSTRACT Drug use during pregnancy is an important social and medical issue. Legislatures and courts have offered a variety of responses, ranging from imprisonment to comprehensive service programs that are rehabilitative in nature. This article discusses the prevalence and effects of prenatal drug use, followed by a presentation of the scope of legal responses and treatment options. Some courts do not provide outreach services for drug-offending mothers, while others may offer a limited range of services. In contrast, a comprehensive justice approach would provide a wide range of health, employment, and social programs for the offender. This approach is based on philosophies of restorative justice, therapeutic jurisprudence, and procedural justice. Such a theory-based comprehensive justice program ultimately benefits mothers, children, and the community. Considerations are offered for judges who seek to implement a comprehensive justice approach to address this important problem. [source] NMR spectroscopy of citrate in solids: cross-polarization kinetics in weakly coupled systemsMAGNETIC RESONANCE IN CHEMISTRY, Issue 5 2008Jian Feng Abstract Solid-state NMR spectroscopy is a potentially powerful method for obtaining molecular level structural information crucial for understanding the specific relationship between calcite crystals and occluded organic molecules that are important in biomineralization and biomimetic materials. In this work, a method is developed based on cross-polarization/magic angle spinning (CP/MAS) NMR to measure the heteronuclear distances and obtain structural information for large intracrystalline citrate defects in a synthetic calcite/citrate composite. Using compounds with well-characterized crystal structures, Mg(II) citrate and Sr(II) citrate, a correlation is established between TIS, the CP time, and M2IS, the van Vleck heteronuclear dipolar second moment, which contains distance and structural information. This correlation is supported by peak assignments obtained from calculations of the 13C chemical shifts for crystalline Mg(II) citrate. On the basis of TIS,1versusM2IS correlation, measurement of TIS for carbonate ions associated with citrate defects in a calcite(13C-enriched)/citrate coprecipitate yields an estimate for the distance between citrate and the nearest carbonate carbon that indicates close spatial proximity and provides useful constraints for future computational study. The applicability of TIS,1versusM2IS correlations to other weakly coupled spin-1/2 systems is discussed in terms of the effects of 1H homonuclear dipolar coupling, using the CP kinetics of Zn(II) dihydroxybenzoate and kaolinite for comparison. The results suggest a limited range of correlation constants and indicate that quantitative information can be obtained from CP/MAS kinetics obtained under similar experimental conditions. Copyright © 2008 John Wiley & Sons, Ltd. [source] Arabidopsis pathology breathes new life into the necrotrophs-vs.-biotrophs classification of fungal pathogensMOLECULAR PLANT PATHOLOGY, Issue 4 2004RICHARD P. OLIVER SUMMARY Fungal plant pathologists have for many decades attempted to classify pathogens into groups called necrotrophs, biotrophs and, more recently, hemibiotrophs. Although these terms are well known and frequently used, disagreements about which pathogens fall into which classes, as well as the precise definition of these terms, has conspired to limit their usefulness. Dogmas concerning the properties of the classes have been progressively eroded. However, the genetic analysis of disease resistance, particularly in the model plant Arabidopsis thaliana, has provided a biologically meaningful division based on whether defence against fungal pathogens is controlled via the salicylate or jasmonate/ethylene pathways. This mode-of-defence division distinguishes necrotrophs and biotrophs but it limits the biotroph class to pathogens that possess haustoria. The small number and limited range of pathogens that infect Arabidopsis means that several interesting questions are still unanswered. Do hemibiotrophs represents a distinct class or a subclass of the necrotrophs? Does the division apply to other plant families and particularly to cereals? and does this classification help us understand the intricacies of either fungal pathogenicity or plant defence? [source] Increasingly distant from life: problem setting in the organization of home careNURSING PHILOSOPHY, Issue 1 2008Christine Ceci PhD Abstract, The analysis undertaken in this paper explores the significance of a central finding from a recent field study of home care case management practice: a notable feature of case management work is the preparation of an orderly, ordered space where care may be offered. However, out of their encounters with an almost endless variety of situations, out of people's diverse narratives of need, case managers seem able to pick out only limited range of recognized needs to which to respond and demonstrate a series of responses themselves equally limited. Though this observation suggests a kind of efficiency that is currently highly valued within healthcare systems, it also underlines the system's inability to engage difference and variability in a meaningful way. This inability or limitation in effectively engaging difference is conceptualized here as, in some sense, a problem, and the nature of this problem is explored through the rhetorical process of problem setting. The central question becomes how might we develop and deploy an orderly and coherent system of care without essentializing people's experiences, without treating these experiences reductively, without, in a Foucaultian frame of reference, allowing what can be understood as similarity or resemblance among clients and situations to be folded back into sameness? As we encounter complexity, variability and difference in practice, how should we treat it? [source] A sterile-female technique proposed for control of Striga hermonthica and other intractable weeds: advantages, shortcomings and risk managementPEST MANAGEMENT SCIENCE (FORMERLY: PESTICIDE SCIENCE), Issue 5 2009Brian G Rector Abstract Weeds have posed intractable challenges to farmers since the dawn of agriculture. This article describes in detail a proposed control strategy based on the introduction of genes conferring female sterility into the genome of an intractable target weed. Spread of these genes through target populations via pollen would be facilitated by their incorporation within active transposable elements. Advantages (e.g. self-dissemination, self-proliferation, target specificity) and shortcomings (e.g. high cost, long project incubation period, limited range of possible targets) of this strategy are discussed in depth, as are assessment and management of its attendant biological and ecological risks, such as the risk of introduced genes spreading to non-target species. The parasitic weed Striga hermonthica (Del.) Benth. is examined as a potential target. Published 2009 by John Wiley & Sons, Ltd [source] Characterisation of aurone biosynthesis in Antirrhinum majusPHYSIOLOGIA PLANTARUM, Issue 4 2006Kevin M. Davies Aurones are bright yellow flavonoids produced in petals of a limited range of plant species, including Antirrhinum majus. The biosynthesis of aurones is thought to occur by the action of aureusidin synthase (AUS), and possibly aureusidin 7- O -glucosyltransferase (A7GT). The temporal and spatial occurrence of AUS and A7GT transcript was examined in wild-type A. majus and two mutant lines; sulfurea, which has increased aurone production in petals, and violacea, which has reduced aurone production. AUS and A7GT transcript abundance was similar in all three lines, increasing during flower development coincident with yellow coloration. The spatial pattern of AUS occurrence was also similar in all three lines, being spatially restricted to the inner epidermis of the face and throat of the lower petal. A new recessive line (CFR1011) with greatly reduced aurone production in all parts of the petal was identified by ethylmethanesulfonate mutagenesis of the homozygous recessive sulfurea line. Transcript abundance for AUS was not changed in the CFR1011 line compared with the wild-type line, and neither were any point mutations detected in the coding sequences for AUS or A7GT. Thus, the sulfurea, violacea and CFR1011 mutations do not seem to control aurone production through a change in transcript abundance of the predicted biosynthetic genes AUS or A7GT. To examine AUS gene regulation further, the putative AUS gene promoter region was isolated and compared with other A. majus flavonoid gene promoters. A number of conserved potential regulatory regions were identified, in particular a consensus site for the MYB-type transcription factors. [source] Chemically-mediated host-plant location and selection by root-feeding insectsPHYSIOLOGICAL ENTOMOLOGY, Issue 1 2006Scott N. Johnson Abstract., Recent studies have shown that root-feeding insects can be of considerable importance in terms of agricultural damage, their indirect impacts on above-ground herbivores and their efficacy as biocontrol agents of weeds. To date, isolated studies have made it difficult to identify the mechanisms by which soil-dwelling insects locate and select host-plant roots. This review synthesizes 78 studies describing root location and selection. Soil insect herbivores do not rely on encountering roots at random, but orientate towards them using semiochemicals that enable specialist insects to distinguish host-plants from unsuitable plants. Secondary plant metabolites released into the rhizosphere (alcohols, esters and aldehydes representing 37% of reported examples) underpin host-plant location and recognition, with 80% having ,attractant' properties. Insects feeding on a limited range of plants tend to exploit host-specific secondary metabolites, whereas nonspecialist feeders appear to use more general semiochemicals. When insects reach the roots, contact chemosensory cues act as either ,phagostimulants' (48% of the compounds being sugars) or feeding ,deterrents' (notably phenolic compounds). Twenty studies conclude that CO2 is the major primary plant metabolite that allows insects to locate to roots. However, several features of CO2 emissions from roots mitigate against it as a precise location cue. In addition to its lack of specificity, gradients of root emitted CO2 do not persist for long periods and vertical gradients of CO2 in the soil tend to be stronger than horizontal gradients. A conceptual model is presented, emphasizing the importance of soil properties (e.g. porosity, moisture) on chemical diffusion and insect motility. [source] Entropy,enthalpy compensation: Fact or artifact?PROTEIN SCIENCE, Issue 3 2001Kim Sharp Abstract The phenomenon of entropy,enthalpy (S-H) compensation is widely invoked as an explanatory principle in thermodynamic analyses of proteins, ligands, and nucleic acids. It has been suggested that this compensation is an intrinsic property of either complex, fluctuating, or aqueous systems. The questions examined here are whether the observed compensation is extra-thermodynamic (i.e., reflects anything more than the well-known laws of statistical thermodynamics) and if so, what does it reveal about the system? Compensation is rather variably defined in the literature and different usages are discussed. The most precise and interesting one, which is considered here, is a linear relationship between ,H and ,S for some series of perturbations or changes in experimental variable. Some recent thermodynamic data on proteins purporting to show compensation is analyzed and shown to be better explained by other causes. A general statistical mechanical model of a complex system is analyzed to explore whether and under what conditions extra-thermodynamic compensation can occur and what it reveals about the system. This model shows that the most likely behavior to be seen is linear S-H compensation over a rather limited range of perturbations with a compensation temperature Tc = d,H/d,S within 20% of the experimental temperature. This behavior is insensitive to the details of the model, thus revealing little extra-thermodynamic or causal information about the system. In addition, it will likely be difficult to distinguish this from more trivial forms of compensation in real experimental systems. [source] SITUATING ADMINISTRATIVE RESPONSIBILITY: A COMPARISON OF MEDIEVAL CHRISTIAN AND MEDIEVAL ISLAMIC ADMINISTRATIVE THOUGHTPUBLIC ADMINISTRATION, Issue 3 2006SARAR. Contemporary studies of administrative thought allow only a limited range of viability for medieval and non-Western thought on the subject of public administration. This tendency belies the wealth of thought embedded within this broad literature. This paper investigates the matter of administrative accountability and responsibility through the lens of a comparative theorist of historical administrative thought. In order to assess the explanatory potential of early and non-Western administrative studies, two texts have been chosen, both previously unanalysed in conjunction (to the best of my knowledge) from the perspective of the administrative theorist , John of Salisbury's Policraticus and Abu al-Hassan Al-Mawardi's Al-Akham al-Sultaniyya w'al-Wilayat al Diniyya (The Ordinances of Government). Through an analysis of ideas of delegation and responsibility within these texts, the paper seeks to develop a critique of the place of revealed religious authority in the solution to the questions ,who are administrators responsible to?' and ,what are administrators responsible for?' [source] Relationship of habitat stability and intra-specific population dynamics of an obligate corallivore butterflyfishAQUATIC CONSERVATION: MARINE AND FRESHWATER ECOSYSTEMS, Issue S1 2005Michael P. Crosby Abstract 1.Intra-specific behavioural manifestations, as measured by territory size and conspecific agonistic encounters, population size and recruitment of the obligate corallivore butterflyfish Chaetodon multicinctus (Family: Chaetodontidae) were examined over a 5-year period at three Hawaiian coral reef sites, each receiving different levels of non-point-source terrigenous sediment runoff. 2.All three sites indicated significant correlations for percentage coral cover with territory size, fish size, and number of adult C. multicinctus, and for agonistic encounters with number of juvenile C. multicinctus. However, the site most impacted by sediment runoff indicated no significant correlations for percentage coral cover with territory size, fish length, number of adult C. multicinctus, number of agonistic encounters, or C. multicinctus juveniles; nor for number of agonistic encounters with number of juveniles. 3.The site moderately to minimally impacted by sediment runoff exhibited significant correlations for percentage coral cover with number of adults, while the site with no sedimentation impacts exhibited significant correlations for percentage coral cover with fish size, number of adults and number of juveniles. 4.Significant differences were found to exist between all three sites for agonistic encounters, territory size, fish size, number of C. multicinctus juveniles and percentage coral cover. The most highly impacted site exhibited a significantly higher number of adult C. multicinctus that were significantly smaller in size than either the minimally impacted and non-impacted sites. 5.The study design purposely selected high coral cover habitats (means ranged from 81.4% to 96.5%) at each site. Within this limited range of relatively high coral cover habitat, relative habitat stability resulting from a range of historic sediment inputs between sites appears to be the stronger forcing function for observed intra-specific behavioural manifestations, population size and recruitment than percentage coral cover. 6.Study results indicate that obligate corallivore butterflyfish behavioural manifestations, population size and recruitment may be used as a benchmark for changes in habitat stability for coral reef communities, and support the general premise of the butterflyfish indicator species hypothesis. Copyright © 2005 John Wiley & Sons, Ltd. [source] Using LiDAR to detect cultural resources in a forested environment: an example from Isle Royale National Park, Michigan, USAARCHAEOLOGICAL PROSPECTION, Issue 3 2008Julie M. Gallagher Abstract This article discusses the use of light detecting and ranging (LiDAR) technology as an effective remote sensing tool for the location of cultural resources. Its use, particularly in Europe, has proven successful in the identification of archaeological sites obscured by dense vegetation or surface disturbances. This study used LiDAR-derived imagery to detect pre- and post-European contact sites, and their related features, in densely forested environments on Isle Royale, Michigan, USA. LiDAR bare-Earth models were used to ,see through' the vegetation in an effort to: (i) identify cultural features prior to the implementation of a pedestrian reconnaissance survey; (ii) aid in the development of a more informed survey strategy; and (iii) produce an overall safer, more efficient and more cost-effective research design. Three study areas were selected for investigation. Within these three study areas, a total of seven investigation locales containing 32 separate features were identified using LiDAR-derived imagery. Eighteen of the 32 features were found to have been previously recorded. Of the remaining 14 features, seven were confirmed in the field as being cultural features and were recorded for the first time as a result of this investigation. The remaining seven could not be located on the ground or were found to be non-cultural. The results of this study support the use of LiDAR as a viable method for the detection of cultural resources, particularly in remote and heavily forested environments. Despite its positive contributions, there is a limited range of archaeological (surface) features that can be detected using this technology. As applied to archaeology, LiDAR is not an exclusive investigatory technique. It must be part of a comprehensive research strategy that integrates field, laboratory and archival investigation in order to achieve the best possible interpretation of the archaeological record. Copyright © 2008 John Wiley & Sons, Ltd. [source] ANALYSIS OF NASRID POLYCHROME CARPENTRY AT THE HALL OF THE MEXUAR PALACE, ALHAMBRA COMPLEX (GRANADA, SPAIN), COMBINING MICROSCOPIC, CHROMATOGRAPHIC AND SPECTROSCOPIC METHODS,ARCHAEOMETRY, Issue 4 2009C. CARDELL The pigments, binders and execution techniques used by the Nasrids (1238,1492) to polychrome carpentry in the Hall of the Mexuar Palace at the Alhambra (Granada, Spain) were studied using optical microscopy, scanning electron microscopy with EDX analysis, selective staining techniques and gas chromatography , mass spectrometry. This pioneering investigation presents the first results of a research project devoted to filling gaps in the knowledge of Nasrid art, traditionally approached by stylistic studies. Moreover, it is essential for the polychromy conservation of the studied artworks, and will help to clarify historical and painting uncertainties in the Alhambra monument. The palette consists of a limited range of colours: white (lead-base pigment), red (cinnabar and red lead), blue (lapis lazuli), black (carbon-based) and false gold (golden tin). Tempera grassa was the painting technique identified. Two types of grounds were used: (i) gypsum in calligraphy decoration for the false gold technique, and (ii) synthetic minium in geometric drawings in carpentry. Organic insulating layers of linseed oil were used between paint strata. Artists applied synthetic minium to protect the wood (Juglans regia and conifer) against attack by xylophages. To lighten the surface darkened by this ground layer, powdered tin was added to achieve a metallic lustre. [source] Functional and prognostic relevance of the ,173 polymorphism of the macrophage migration inhibitory factor gene in systemic-onset juvenile idiopathic arthritisARTHRITIS & RHEUMATISM, Issue 5 2003Fabrizio De Benedetti Objective To address the functional and prognostic relevance of the ,173 single-nucleotide G-to-C polymorphism of the macrophage migration inhibitory factor (MIF) gene in patients with systemic-onset juvenile idiopathic arthritis (systemic-onset JIA) by evaluating its association with serum and synovial fluid levels of MIF, with glucocorticoid requirement, and with the outcome of the disease. Methods A total of 136 patients with systemic-onset JIA were studied, including 98 patients from the British Paediatric Rheumatology Study Group's National Repository for JIA and 38 patients who were followed up at the IRCCS Policlinico San Matteo (Pavia, Italy) and the IRCCS G. Gaslini (Genoa, Italy). The MIF-173 polymorphism was genotyped using SnaPshot ddNTP primer extension and capillary electrophoresis. MIF levels were measured by enzyme-linked immunosorbent assay. The evaluation of the association of the MIF-173 polymorphism with outcome was performed only in Italian patients who were followed up for >5 years, by analyzing retrospectively 1) the number of joints with active arthritis and the number of joints with limited range of motion; 2) the score, at the last visit, on the Italian version of the Childhood Health Assessment Questionnaire (C-HAQ); and 3) data concerning the treatment regimens during the disease course. Results Systemic-onset JIA patients carrying a MIF-173*C allele had serum and synovial fluid levels of MIF significantly higher than those in patients with the GG genotype. The duration of glucocorticoid treatment on a daily regimen was significantly longer in patients carrying a MIF-173*C allele than in MIF-173 GG homozygous patients. Moreover, the duration of clinical response to intraarticular injection of triamcinolone hexacetonide was significantly shorter in patients carrying a MIF-173*C allele. At the last visit, the numbers of joints with active arthritis, the C-HAQ scores, and the numbers of joints with limited range of motion were significantly higher in patients carrying the MIF-173*C allele. Conclusion Our study shows the functional relevance of the MIF-173 polymorphism and suggests that the MIF-173*C allele is a predictor of poor outcome in systemic-onset JIA. [source] | |||||||||||||||||||||||||||||||||||||||||||