Construction of smooth closed surfaces by ball functions on a cube

In Computer Aided Geometric Design (CAGD), surface constructions are basically formed from collections of surface patches, by placing a certain continuity condition between adjacent patches. Even though tensor product BŽzier patches are currently used extensively in most CAGD systems to model free-form surfaces, this method can only be used to generate closed surface of genus one, i.e. a surface which is equivalent to a torus. A surface with tangent plane continuity is known as a first order geometrically smooth surface or a G1 surface. This paper presents a simple G1 surface construction method, i.e. a surface of genus zero, by defining Ball bicubic functions on faces of a cube. The constructed basis functions have small support and sum to one. The functions are useful for designing, approximating and interpolating a simple closed surface of genus zero. This construction method was first introduced by Goodman in 1991 who defined biquadratic generalised B-spline functions on faces of a simple quadrilateral mesh. Several examples of surfaces/objects which are constructed by the proposed method are presented in this paper

Migration experiences, employment status and psychological distress among Somali immigrants: a mixed-method international study

Background: The discourse about mental health problems among migrants and refugees tends to focus on adverse pre-migration experiences; there is less investigation of the environmental conditions in which refugee migrants live, and the contrasts between these situations in different countries. This cross-national study of two samples of Somali refugees living in London (UK) and Minneapolis, Minnesota, (USA) helps to fill a gap in the literature, and is unusual in being able to compare information collected in the same way in two cities in different countries. Methods: There were two parts to the study, focus groups to gather in-depth qualitative data and a survey of health status and quantifiable demographic and material factors. Three of the focus groups involved nineteen Somali professionals and five groups included twenty-eight lay Somalis who were living in London and Minneapolis. The quantitative survey was done with 189 Somali respondents, also living in London and Minneapolis. We used the MINI International Neuropsychiatric Interview (MINI) to assess ICD-10 and Results: The overall qualitative and quantitative results suggested that challenges to masculinity, thwarted aspirations, devalued refugee identity, unemployment, legal uncertainties and longer duration of stay in the host country account for poor psychological well-being and psychiatric disorders among this group. Conclusion: The use of a mixed-methods approach in this international study was essential since the quantitative and qualitative data provide different layers and depth of meaning and complement each other to provide a fuller picture of complex and multi-faceted life situations of refugees and asylum seekers. The comparison between the UK and US suggests that greater flexibility of access to labour markets for this refugee group might help to promote opportunities for better integration and mental well-being

Selective Deletion of PTEN in Dopamine Neurons Leads to Trophic Effects and Adaptation of Striatal Medium Spiny Projecting Neurons

The widespread distribution of the tumor suppressor PTEN in the nervous system suggests a role in a broad range of brain functions. PTEN negatively regulates the signaling pathways initiated by protein kinase B (Akt) thereby regulating signals for growth, proliferation and cell survival. Pten deletion in the mouse brain has revealed its role in controlling cell size and number. In this study, we used Cre-loxP technology to specifically inactivate Pten in dopamine (DA) neurons (Pten KO mice). The resulting mutant mice showed neuronal hypertrophy, and an increased number of dopaminergic neurons and fibers in the ventral mesencephalon. Interestingly, quantitative microdialysis studies in Pten KO mice revealed no alterations in basal DA extracellular levels or evoked DA release in the dorsal striatum, despite a significant increase in total DA tissue levels. Striatal dopamine receptor D1 (DRD1) and prodynorphin (PDyn) mRNA levels were significantly elevated in KO animals, suggesting an enhancement in neuronal activity associated with the striatonigral projection pathway, while dopamine receptor D2 (DRD2) and preproenkephalin (PPE) mRNA levels remained unchanged. In addition, PTEN inactivation protected DA neurons and significantly enhanced DA-dependent behavioral functions in KO mice after a progressive 6OHDA lesion. These results provide further evidence about the role of PTEN in the brain and suggest that manipulation of the PTEN/Akt signaling pathway during development may alter the basal state of dopaminergic neurotransmission and could provide a therapeutic strategy for the treatment of Parkinson's disease, and other neurodegenerative disorders

Molecular fingerprinting of radiation resistant tumors: Can we apprehend and rehabilitate the suspects?

Radiation therapy continues to be one of the more popular treatment options for localized prostate cancer. One major obstacle to radiation therapy is that there is a limit to the amount of radiation that can be safely delivered to the target organ. Emerging evidence suggests that therapeutic agents targeting specific molecules might be combined with radiation therapy for more effective treatment of tumors. Recent studies suggest that modulation of these molecules by a variety of mechanisms (e.g., gene therapy, antisense oligonucleotides, small interfering RNA) may enhance the efficacy of radiation therapy by modifying the activity of key cell proliferation and survival pathways such as those controlled by Bcl-2, p53, Akt/PTEN and cyclooxygenase-2. In this article, we summarize the findings of recent investigations of radiosensitizing agents in the treatment of prostate cancer

Long-term behavioural impact of an integrated home garden intervention: evidence from Bangladesh

Integrated home garden interventions combine training in gardening practices with education about nutrition knowledge. Such interventions have been shown to improve nutrition behaviour in low income countries. However, to date rigorous evidence is lacking for their long-term impact. We test the impact of an integrated home garden intervention on vegetable production and consumption three years after the intervention ended. We analyse three rounds of survey data for 224 control and 395 intervention households in rural Bangladesh. Three years after the intervention, the average impact on vegetable production per household was 43 kg/year (+49% over baseline levels; p < 0.01), and the effect was not statistically different from the impact one year after the intervention, which demonstrates that impact was maintained in the long-term. The impact on the micronutrient supply for iron, zinc, folate and pro-vitamin A from home gardens was maintained in the long term. These impacts may have been driven by the long-term improvements in women’s nutrition knowledge and gardening practices, explaining the sustainability of the behavioural nutrition change. We also identify positive impacts on women’s empowerment and women’s output market participation, highlighting how integrated programs, even if modest in scope, can be drivers of social change