Main Forms (main + form)

Distribution by Scientific Domains


Selected Abstracts


Cytoplasmic localization of oocyte-specific variant of porcine DNA methyltransferase-1 during early development

DEVELOPMENTAL DYNAMICS, Issue 7 2009
Young Sun Jeong
Abstract DNA methyltransferase-1 (Dnmt1) is involved in the maintenance of genomic methylation patterns. Rather than full-length Dnmt1, mouse oocytes have a truncated variant called Dnmt1o. Immunofluorescence data showed that Dnmt1o localized to the cytoplasm, but this has not been confirmed using more direct methods. The cytoplasmic localization of Dnmt1o has been assigned to the main cause of global DNA demethylation in early mouse embryos. We studied localization of Dnmt1o in mouse and pig embryos. We identified pig Dnmt1o protein and its transcript with unique 5,-end sequence. Physically separating mouse and pig 2-cell embryos into their nuclear and cytoplasmic components demonstrated that Dnmt1o of both species localized to the cytoplasm. Cloned pig embryos had Dnmt1o as the main form, with no indication of somatic Dnmt1. These findings indicate that Dnmt1o is cytoplasmic during early development; its presence in both pig and mouse embryos further suggests that Dnmt1o is conserved in mammals. Developmental Dynamics 238:1666,1673, 2009. © 2009 Wiley-Liss, Inc. [source]


Do male and female black-backed woodpeckers respond differently to gaps in habitat?

EVOLUTIONARY APPLICATIONS (ELECTRONIC), Issue 3 2010
Jennifer C. Pierson
Abstract We used population- and individual-based genetic approaches to assess barriers to movement in black-backed woodpeckers (Picoides arcticus), a fire-specialist that mainly occupies the boreal forest in North America. We tested if male and female woodpeckers exhibited the same movement patterns using both spatially implicit and explicit genetic analyses to define population structure and movement patterns of both sexes among populations. Three genetic groups were identified, a large, genetically continuous population that spans from the Rocky Mountains to Quebec, a small isolated population in South Dakota and a separate population in the western portion of their distribution (Oregon). Patterns of genetic diversity suggest extensive gene flow mediated by both males and females within the continuous boreal forest. However, male-mediated gene flow is the main form of connectivity between the continuously distributed group and the smaller populations of South Dakota and Oregon that are separated by large areas of unforested habitat, which apparently serves as a barrier to movement of female woodpeckers. [source]


Effect of application form of nitrogen on oxalate accumulation and mineral uptake by napiergrass (Pennisetum purpureum)

GRASSLAND SCIENCE, Issue 3 2010
Mohammad Mijanur Rahman
Abstract Oxalate occurs naturally in forage species, but excess levels of soluble oxalate adversely affect their nutritional quality as animal feed. Although induction of oxalate in plants has been associated with nitrate application, relatively little is known about oxalate in forage grasses. In the present study, we investigated oxalate accumulation and mineral uptake by napiergrass (Pennisetum purpureum, cv. dwarf-late) cultured in complete nutrient solution containing either solely nitrate or mainly ammonium as the main form of nitrogen. Total (shoot and root) yield of plants did not differ significantly between the nitrate and ammonium treatments. By contrast, the nitrogen form significantly affected oxalate accumulation and mineral uptake by plants. Nitrate application resulted in higher concentrations of soluble and insoluble oxalates in the shoot and soluble oxalate in the root than ammonium application. Nitrate application also resulted in higher concentrations of sodium and calcium in the shoot, and higher concentrations of sodium, calcium and magnesium in the root than ammonium application. The results suggest that the application of nitrate fertilizer as the sole source of nitrogen should be avoided in the cultivation of oxalate-rich forages, though further studies are needed under field conditions. [source]


Higher education: marketing in a quasi-commercial service industry

INTERNATIONAL JOURNAL OF NONPROFIT & VOLUNTARY SECTOR MARKETING, Issue 2 2003
Mari Brookes
The UK Government is promoting widening participation and asking universities to develop their student intake of 18,30 year-olds by 50 per cent by 2010. The financing of these changes is encouraging a marketing emphasis shift, as funding is reduced and alternative revenue methods sought. Traditional marketing of charitable educational institutions sought to ensure sufficient student enrolments for solely government-funded core activities. Further marketing is now seen in quasi-commercial activities. This paper investigates the need for a further marketing approach to satisfy these government policy changes. Using the comparative method, the paper looks at the complexity of the issues around US and UK higher education and their revenue value conflicts, marketing perspectives and, finally, the differences in perspectives and expectations between commerce and education. As the matter is current and ongoing, the main form of collecting evidence is through personal interview and recent media releases. Copyright © 2003 Henry Stewart Publications [source]


Migration of Highly Skilled Chinese to Europe: Trends and Perspective

INTERNATIONAL MIGRATION, Issue 3 2003
Guochu Zhang
Since China's economic opening and reforms in 1978, the country has broadened and deepened its exchanges and relations with other countries. This has contributed to the increase in the scale of international migration of highly skilled Chinese abroad. The impact of the migration of highly skilled Chinese on China and the relevant nations particularly deserve attention and study. Following the earlier migration flows mainly to the United States, Japan, Canada, Australia, and New Zealand, the migration of highly skilled Chinese to Europe has become a notable new trend. Currently, the flow of international migration of highly skilled Chinese personnel is mainly oriented toward Europe and the United States. While studying abroad has been the main form of migration of the skilled, this has now been joined by the migration of technical and professional staff, and the trend is increasing. The main country of destination for Chinese students is the United States, which absorbs more than half of the total, while Australia and Canada receive the largest number of skilled Chinese manpower. The United States also receives a large number of Chinese technical personnel, but its proportion has declined, while the flow to Europe has sharply increased. This development may be attributed to the global expansion of economic, scientific and technological, as well as cultural and educational exchanges and cooperation. But it is also the result of an increase in the educational investment made by the Chinese people following the continuous increase in China's economic strength and the population's personal income. Of greater importance are the gaps between China and Europe at the scientific, technological, and educational levels and the research and marketing environment. The intervening changes in labour market and immigration policies in European and American countries accelerate the trend further. For all of these and other reasons, the spatial distribution of Chinese students will become more balanced and play a positive role in the promotion of mutually beneficial exchanges between China and other countries. [source]


Genetic and epigenetic heterogeneity in cancer: A genome-centric perspective

JOURNAL OF CELLULAR PHYSIOLOGY, Issue 3 2009
Henry H.Q. Heng
Genetic and epigenetic heterogeneity (the main form of non-genetic heterogeneity) are key elements in cancer progression and drug resistance, as they provide needed population diversity, complexity, and robustness. Despite drastically increased evidence of multiple levels of heterogeneity in cancer, the general approach has been to eliminate the "noise" of heterogeneity to establish genetic and epigenetic patterns. In particular, the appreciation of new types of epigenetic regulation like non-coding RNA, have led to the hope of solving the mystery of cancer that the current genetic theories seem to be unable to achieve. In this mini-review, we have briefly analyzed a number of mis-conceptions regarding cancer heterogeneity, followed by the re-evaluation of cancer heterogeneity within a framework of the genome-centric concept of evolution. The analysis of the relationship between gene, epigenetic and genome level heterogeneity, and the challenges of measuring heterogeneity among multiple levels have been discussed. Further, we propose that measuring genome level heterogeneity represents an effective strategy in the study of cancer and other types of complex diseases, as emphasis on the pattern of system evolution rather than specific pathways provides a global and synthetic approach. Compared to the degree of heterogeneity, individual molecular pathways will have limited predictability during stochastic cancer evolution where genome dynamics (reflected by karyotypic heterogeneity) will dominate. J. Cell. Physiol. 220: 538,547, 2009. © 2009 Wiley-Liss, Inc. [source]


Small-scale spatial dynamics of vegetation in a grazed Uruguayan grassland

AUSTRAL ECOLOGY, Issue 4 2009
MARCOS TEXEIRA
Abstract We explored the small-scale plant species mobility in a subhumid native grassland subjected to grazing by cattle in south-western Uruguay. We established four permanent plots of 40 × 40 cm, divided in 16 × 16 cells. In each cell, the presence of species was seasonally recorded for 2 years and annually recorded for 4 years. By nesting the cells, we studied the mobility at different scales, from 6.25 cm2 to 400 cm2. At each scale we measured species richness, cumulative richness and the turnover rates of the dominant species. We found that the cumulative species richness was an increasing power function, with higher accumulation rates with smaller spatial scale. Although species richness showed seasonal fluctuations, the mean species richness was constant during the study period. We detected significant spatio-temporal variability in mobility patterns among species. Certain species showed a high capacity to colonize new sites, whereas other species rotate among sites that they previously occupied. Grazed communities in Uruguayan Campos are structured as a dense matrix of perennials grasses and forbs, where vegetative propagation is the main form of growth of the species. The small-scale dynamics and the high variability in the mobility characteristics could be linked with the diversity of growth forms and spatial strategies of the species in this community. We believe that a high degree of small-scale spatial dynamics contribute to explain the species coexistence and the apparent stability of communities at local scales. [source]


Rupture of chordae tendineae in patients with ,-thalassemia

EUROPEAN JOURNAL OF HAEMATOLOGY, Issue 4 2004
Dimitrios Farmakis
Abstract: Cardiac disease is the primary cause of mortality in , -thalassemia patients. Except for ventricular dysfunction and pulmonary hypertension that represent the main forms of heart disease in these patients, valvular abnormalities including valvular regurgitation, endocardial thickening and calcification and mitral valve prolapse have also been described. Here we present two patients with thalassemia major and mitral chordal rupture, a previously undescribed abnormality in this population. Pathogenesis of this finding may involve thalassemia-related pseudoxanthoma elasticum-like syndrome, a diffuse elastic tissue defect, which is observed with a notable frequency in these patients and has been associated with numerous cardiovascular complications, including valvular ones. [source]


Molecular and clinical heterogeneity in CLCN7-dependent osteopetrosis: report of 20 novel mutations,

HUMAN MUTATION, Issue 1 2010
Alessandra Pangrazio
Abstract The "Osteopetroses" are genetic diseases whose clinical picture is caused by a defect in bone resorption by osteoclasts. Three main forms can be distinguished on the basis of severity, age of onset and means of inheritance: the dominant benign, the intermediate and the recessive severe form. While several genes have been involved in the pathogenesis of the different types of osteopetroses, the CLCN7 gene has drawn the attention of many researchers, as mutations within this gene are associated with very different phenotypes. We report here the characterization of 25 unpublished patients which has resulted in the identification of 20 novel mutations, including 11 missense mutations, 6 causing premature termination, 1 small deletion and 2 putative splice site defects. Careful analysis of clinical and molecular data led us to several conclusions. First, intermediate osteopetrosis is not homogeneous, since it can comprise both severe dominant forms with an early onset and recessive ones without central nervous system involvement. Second, the appropriateness of haematopoietic stem cell transplantation in CLCN7-dependent ARO patients has to be carefully evaluated and exhaustive CNS examination is strongly suggested, as transplantation can almost completely cure the disease in situations where no primary neurological symptoms are present. Finally, the analysis of this largest cohort of CLCN7-dependent ARO patients together with some ADO II families allowed us to draw preliminary genotype-phenotype correlations suggesting that haploinsufficiency is not the mechanism causing ADO II. The availability of biochemical assays to characterize ClC-7 function will help to confirm this hypothesis. © 2009 Wiley-Liss, Inc. [source]


Creating space for preferred identities: narrative practice conversations about gender and culture in the context of trauma

JOURNAL OF FAMILY THERAPY, Issue 1 2010
Pennie J. Blackburn
This paper describes a narrative approach to work with the effects of extreme trauma and forced migration. It describes an approach to work across cultures in cases in which the culturally informed dominant discourses have shaped the effects of the trauma on those that survived them. The paper sets out the stories of two women as exemplars of the complexities of such practice. Examples of the main forms of narrative practice conversations are given and the work is developed through considerations of ways in which therapists can work respectfully between cultures. [source]


From National Service to Global Player: Transforming the Organizational Logic of a Public Broadcaster

JOURNAL OF MANAGEMENT STUDIES, Issue 6 2010
André Spicer
abstract We present organizational logics as a meso-level construct that lies between institutional theory's field-level logics and the sense-making activities of individual agents in organizations. We argue that an institutional logic can be operationalized empirically using the concept of a discourse , that is, a coherent symbolic system articulating what constitutes legitimate, reasonable, and effective conduct in, around, and by organizations. An organization may, moreover, be simultaneously exposed to several institutional logics that make up its broader ideational environment. Taking these three observations together enables us to consider an organizational logic as a spatially and temporally localized configuration of diverse discourses. We go on to show how organizational logics were transformed in the Australian Broadcasting Corporation between 1953 and 1999 by examining the changing discourses that appeared in the Corporation's annual reports. We argue that these discourses were modified through three main forms of discursive agency: (1) undertaking acts of ironic accommodation between competing discourses; (2) building chains of equivalence between the potentially contradictory discourses; and (3) reconciling new and old discourses through pragmatic acts of ,bricolage'. We found that, using these forms of discursive agency, a powerful coalition of actors was able to transform the dominant organizational logic of the ABC from one where the Corporation's initial mission was to serve national interests through public service to one that was ultimately focused on participating in a globalized media market. Finally, we note that discursive resources could be used as the basis for resistance by less powerful agents, although further research is necessary to determine exactly how more powerful and less powerful agents interact around the establishment of an organizational logic. [source]


Genetic consequences of habitat fragmentation in plant populations: susceptible signals in plant traits and methodological approaches

MOLECULAR ECOLOGY, Issue 24 2008
RAMIRO AGUILAR
Abstract Conservation of genetic diversity, one of the three main forms of biodiversity, is a fundamental concern in conservation biology as it provides the raw material for evolutionary change and thus the potential to adapt to changing environments. By means of meta-analyses, we tested the generality of the hypotheses that habitat fragmentation affects genetic diversity of plant populations and that certain life history and ecological traits of plants can determine differential susceptibility to genetic erosion in fragmented habitats. Additionally, we assessed whether certain methodological approaches used by authors influence the ability to detect fragmentation effects on plant genetic diversity. We found overall large and negative effects of fragmentation on genetic diversity and outcrossing rates but no effects on inbreeding coefficients. Significant increases in inbreeding coefficient in fragmented habitats were only observed in studies analyzing progenies. The mating system and the rarity status of plants explained the highest proportion of variation in the effect sizes among species. The age of the fragment was also decisive in explaining variability among effect sizes: the larger the number of generations elapsed in fragmentation conditions, the larger the negative magnitude of effect sizes on heterozygosity. Our results also suggest that fragmentation is shifting mating patterns towards increased selfing. We conclude that current conservation efforts in fragmented habitats should be focused on common or recently rare species and mainly outcrossing species and outline important issues that need to be addressed in future research on this area. [source]


An introduction to medical statistics for health care professionals: Hypothesis tests and estimation

MUSCULOSKELETAL CARE, Issue 2 2005
Elaine Thomas PhD MSc BSc Lecturer in Biostatistics
Abstract This article is the second in a series of three that will give health care professionals (HCPs) a sound introduction to medical statistics (Thomas, 2004). The objective of research is to find out about the population at large. However, it is generally not possible to study the whole of the population and research questions are addressed in an appropriate study sample. The next crucial step is then to use the information from the sample of individuals to make statements about the wider population of like individuals. This procedure of drawing conclusions about the population, based on study data, is known as inferential statistics. The findings from the study give us the best estimate of what is true for the relevant population, given the sample is representative of the population. It is important to consider how accurate this best estimate is, based on a single sample, when compared to the unknown population figure. Any difference between the observed sample result and the population characteristic is termed the sampling error. This article will cover the two main forms of statistical inference (hypothesis tests and estimation) along with issues that need to be addressed when considering the implications of the study results. Copyright © 2005 Whurr Publishers Ltd. [source]


The myth of the best argument: power, deliberation and reason1

THE BRITISH JOURNAL OF SOCIOLOGY, Issue 1 2001
Luigi Pellizzoni
ABSTRACT Power in communication takes two main forms. As ,external' power, it consists in the ability to acknowledge or disregard a speaker or a discourse. As ,internal' power, it is the ability of an argument to eliminate other arguments by demonstrating its superiority. A positive or negative value may be ascribed to these forms of power. Four ideal-typical positions are discussed , strategy, technocracy, constructionism, and deliberation. Public deliberation has three virtues , civic virtue, governance virtue and cognitive virtue. Deliberation lowers the propensity to, and the benefit of, strategic behaviour. It also increases knowledge, enhancing the quality of decisions. For Habermas, the unity of reason is expressed in the possibility of agreement on the most convincing argument. However, sometimes conflicts are deeplying, principles and factual descriptions are profoundly different, and uncertainty is radical. The best argument cannot be found. There is no universal reason. The question is whether non-strategic agreement may spring from the incommensurability of languages. In search of an answer, Rawls's concept of overlapping consensus, the feminist theory of the public sphere, and the idea of deliberation as co-operation are discussed. The argument developed is that the approach to deliberative democracy may be renewed by rethinking its motivational and cognitive elements. Public deliberation is grounded on a pre-political level of co-operation. Intractable controversies may be faced at the level of practices, looking for local, contextual answers. [source]


Practitioner Review: Use of antiepileptic drugs in children

THE JOURNAL OF CHILD PSYCHOLOGY AND PSYCHIATRY AND ALLIED DISCIPLINES, Issue 2 2006
Renzo Guerrini
Background:, The aim in treating epilepsy is to minimise or control seizures with full respect of quality-of-life issues, especially of cognitive functions. Optimal treatment first demands a correct recognition of the major type of seizures, followed by a correct diagnosis of the type of epilepsy or of the specific syndrome. Methods:, Review of data from literature and personal clinical experience in treating children with epilepsy. Results:, After summarising the general aspects on the diagnosis and treatment of the main forms of childhood epilepsy, we review key issues about management of seizure disorders, including when to start treatment, how to proceed when the first treatment fails, and how to set the targets of treatment. A special section is devoted to the new concept of epileptic encephalopathy and to the influence of ,interictal' EEG abnormalities on cognition, behaviour, and motor abilities in children, providing some suggestions on why and how to treat these conditions. A second section approaches the choice of treatment according to the specific syndromes including infantile spasms, focal epilepsies, syndromes with typical absence seizures, the myoclonic epilepsies and the Lennox,Gastaut syndrome. Conclusions:, Antiepileptic drugs (AEDs) can efficiently control seizures in most children. However, the specificity of AEDs is relatively limited, although continuing research is leading to a better understanding of the relationship between pathogenesis and the mechanism(s) and site(s) of drug action. [source]


Economic Regulation: a review of issues

ANNALS OF PUBLIC AND COOPERATIVE ECONOMICS, Issue 4 2002
D. Parker
This article surveys a range of issues relating to economic regulation. It begins by examining market and state failures which provide the basis for arguments in support of regulation. Concentrating on natural monopolies, the article outlines the main forms of economic regulation, namely rate,of,return or cost,of,service regulation, price,cap regulation, and sliding scale regulation, a hybrid between price,cap and rate,of,return approaches. Reference is made to the broad phases that need to be considered in the evolution of natural monopoly regulation. These are concerned with regulating the incumbent monopoly, promoting and policing the development of competition, and maintaining competition once it has been introduced. The last phase may be better served through the use of effective national competition laws rather than dedicated sector regulation. The article also examines the range of factors that are likely to affect the economic efficiency and effectiveness of regulation. These involve a mixture of economic, political and governance conditions. [source]


Transvaginal electrical stimulation in the treatment of urinary incontinence

BJU INTERNATIONAL, Issue 3 2004
J.C.V. Barroso
OBJECTIVE To determine the effectiveness of transvaginal electrical stimulation (TES) in treating urinary incontinence, and to assess the clinical improvement 6 months after ending the treatment. PATIENTS AND METHODS In a double-blind randomized controlled clinical trial, 36 women (24 patients and 12 controls) with stress, urge or mixed urinary incontinence were chosen to use TES or placebo (identical equipment but with no electrical current). The patients had their treatment at home twice a day (20-min sessions) for 12 weeks. They completed a voiding diary and had a urodynamic study at the beginning and end of treatment. They were clinically re-evaluated after 6 months. RESULTS The mean time of use of TES was similar in both groups (, 40 h); the treatment group had a significant increase in maximum bladder capacity (P < 0.02), a significant reduction in the total number of voids (over 24 h; P < 0.02), in the number of episodes of voiding urgency (P < 0.001) and, importantly, in the number of episodes of urinary incontinence (P < 0.001). At the first evaluation, after ending the treatment, 88% of the patients had a significant reduction in symptoms or went into remission. At the 6-month re-evaluation, a third of the patients required another therapeutic approach. CONCLUSION TES is a practical alternative with few side-effects, and is effective for treating the main forms of female urinary incontinence. [source]


Breakdown of teenage placements in Swedish foster and residential care

CHILD & FAMILY SOCIAL WORK, Issue 2 2004
Marie Sallnäs
ABSTRACT This article deals with the problem of breakdown in different types of out-of-home care (foster care/residential care) for Swedish teenagers. How often are such placements prematurely terminated against the wishes and intentions of child welfare authorities? Which factors appear to increase or decrease the risk of placement breakdown? The sample consists of a national cohort of 776 youths who started 922 placements during 1991. Every placement was followed in municipal case files for a maximum period of five years. Between 30 and 37% of all placements were prematurely terminated, the exact figure depending on whether a narrow or wide definition of breakdown was applied. The lowest rates of breakdown were found in kinship care and secure units, the highest in non-kinship foster homes. Teenagers who display antisocial behaviour and/or have mental health problems constitute a high-risk category for most types of out-of-home care, but especially in non-kinship foster homes. Risk factors in relation to breakdown were analysed in the four main forms of Swedish out-of-home care separately (foster homes, privately/publicly run residential care and secure units). The analysis pointed out that risk factors are not the same in all types of care, but antisocial behaviour at time of placement increased the risk in most forms of care. Prior research indicates that placement breakdown is a major problem of child welfare in other countries, and this study found that Sweden is no exception. [source]