423 research outputs found
Camera-on-a-Chip: TeChnology Transfer from saTurn To your Cell phone
The invention of the CMOS active pixel image sensor "camera-on-a-chip" at the NASA Jet Propulsion Laboratory at Caltech and its subsequent development and commercialization via the spinoff company Photobit Corporation are discussed. The article traces the arc of the technology from innovation, technology transfer, and entrepreneurial startup to its use today in nearly all mobile phone cameras, tablet and web cameras, medical and automotive cameras, and many other applications
Biological Implications of Satellite Cells for Scaffold-based Muscle Regenerative Engineering
Satellite cells are anatomically localized along the surface of muscle fibers and have been regarded as a population of muscle-specific progenitors that are responsible for muscle regeneration. In response to muscle injuries, satellite cells are activated to enter the cell cycle, then proliferate and differentiate into mature muscle cells to regenerate damaged myofibers. Unfortunately, this natural repair mechanism is interrupted in conditions such as muscle degenerative diseases or volumetric muscle loss. The function of stem cells is regulated by signals from their local microenvironment which is called the stem cell niche. Current satellite cell-based strategies such as direct cell transplantation are hindered by the low survival and poor distribution of transplanted cells due to lack of the cell niche. Thus, the objective of this project is to develop a cell/biomaterial combination strategy for muscle regeneration based on understanding of the characteristics of satellite cells and their cell niche. First, satellite cells were isolated from the skeletal muscles of a wild-type mouse and expanded in culture. The scaffolds were synthesized to mimic the anisotropic organization of myofibers. Cells were then seeded on scaffolds and cultured. Cellular responses of satellite cells to the scaffolds were measured and analyzed for adhesion, self-renewal, and proliferation. These experiments provided critical insight on the interactions between synthetic biomaterials and satellite cells. In the future, this synthetic scaffold system will optimized with appropriate structural and mechanical properties to facilitate transplantation of satellite cells for muscle regeneration
Genomic basis of insularity and ecological divergence in barn owls (Tyto alba) of the Canary Islands.
Islands, and the particular organisms that populate them, have long fascinated biologists. Due to their isolation, islands offer unique opportunities to study the effect of neutral and adaptive mechanisms in determining genomic and phenotypical divergence. In the Canary Islands, an archipelago rich in endemics, the barn owl (Tyto alba), present in all the islands, is thought to have diverged into a subspecies (T. a. gracilirostris) on the eastern ones, Fuerteventura and Lanzarote. Taking advantage of 40 whole-genomes and modern population genomics tools, we provide the first look at the origin and genetic makeup of barn owls of this archipelago. We show that the Canaries hold diverse, long-standing and monophyletic populations with a neat distinction of gene pools from the different islands. Using a new method, less sensitive to structure than classical F <sub>ST</sub> , to detect regions involved in local adaptation to insular environments, we identified a haplotype-like region likely under selection in all Canaries individuals and genes in this region suggest morphological adaptations to insularity. In the eastern islands, where the subspecies is present, genomic traces of selection pinpoint signs of adapted body proportions and blood pressure, consistent with the smaller size of this population living in a hot arid climate. In turn, genomic regions under selection in the western barn owls from Tenerife showed an enrichment in genes linked to hypoxia, a potential response to inhabiting a small island with a marked altitudinal gradient. Our results illustrate the interplay of neutral and adaptive forces in shaping divergence and early onset speciation
The determinants of hotels' marketing managers' green marketing behaviour
Little is known about the factors underlying the pro-environmental behaviour of marketing managers. This paper explores the determinants of green marketing practices in the Red Sea hotel sector in Egypt. The research model assesses green marketing practices against the personal and organisational values of the marketing managers, together with a range of organisational and demographic variables expected to influence hotels' environmental behaviour. From a valid sample of 89 marketing managers responsible for 194 hotels, it was found that organisational contextual variables, and in particular targeting Western tourists, being affiliated to an international hotel chain and the marketers' own demographics, including age, academic subject studied and gender, were the best predictors of more proactive green marketing. Personal environmental values did not explain the pro-environmental behaviour of marketers, and the organisational environmental values that had explained part of their ethical behaviour had resulted from voluntarism rather than utilitarian or conformance-based values. Government policies also appeared to be ineffective determinants. The implications for green marketing practices are also discussed. © 2010 Taylor & Francis
The capabilities approach and critical social policy: lessons from the majority world?
The capabilities approach (CA) most closely associated with the thinner and thicker versions of Sen and Nussbaum has the potential to provide a paradigm shift for critical social policy, encompassing but also transcending some of the limitations associated with the Marshallian social citizenship approach. The article argues, however, that it cannot simply be imported from the majority world, rather there is a need to bear in mind the critical literature that developed around it. This is generally discussed and then critically applied to case studies of CA in the developed capitalist world, particularly the Equalities Review conducted for the Equality and Human Rights Commission
Best practice considerations on the assessment of robotic assisted surgical systems:results from an international consensus expert panel
Background Health technology assessments (HTAs) of robotic assisted surgery (RAS) face several challenges in assessing the value of robotic surgical platforms. As a result of using different assessment methods, previous HTAs have reached different conclusions when evaluating RAS. While the number of available systems and surgical procedures is rapidly growing, existing frameworks for assessing MedTech provide a starting point, but specific considerations are needed for HTAs of RAS to ensure consistent results. This work aimed to discuss different approaches and produce guidance on evaluating RAS. Methods A consensus conference research methodology was adopted. A panel of 14 experts was assembled with international experience and representing relevant stakeholders: clinicians, health economists, HTA practitioners, policy makers, and industry. A review of previous HTAs was performed and seven key themes were extracted from the literature for consideration. Over five meetings, the panel discussed the key themes and formulated consensus statements. Results A total of ninety-eight previous HTAs were identified from twenty-five total countries. The seven key themes were evidence inclusion and exclusion, patient- and clinician-reported outcomes, the learning curve, allocation of costs, appropriate time horizons, economic analysis methods, and robotic ecosystem/wider benefits. Conclusions Robotic surgical platforms are tools, not therapies. Their value varies according to context and should be considered across therapeutic areas and stakeholders. The principles set out in this paper should help HTA bodies at all levels to evaluate RAS. This work may serve as a case study for rapidly developing areas in MedTech that require particular consideration for HTAs.</p
Coal in the 21st Century: a climate of change and uncertainty
Coal presents a particular set of challenges when balancing energy policy goals. Despite presenting viable solutions to the problems of energy security and global energy poverty, coal struggles, given its greenhouse-gas drawbacks, in a world of increasingly harmful climate change. Notwithstanding the harm caused to the environment, coal remains an expanding low-price route to meeting local energy needs. It is forecasted to remain a major global resource for the foreseeable future. In the short term it is predicted to have a 26% share of the global energy mix. Recent years have witnessed severe deviations from previously stable trends in coal markets and policy dynamics. According to the predictions by the International Energy Agency (IEA), a variety of factors ranging from the planned phase-out of coal in countries such as Denmark, France and the UK, to changes in policy in China and import-dependency in India, and demand drop in the US have together resulted in the largest decline in coal production in 2015 since 1971 (IEA, Coal Information, 2016). This paper seeks to outline basic coal facts, recent market trends and directions globally and provides an overview of issues shaping the future of coal in the twenty-first century. This paper seeks to outline basic coal facts, recent market trends and directions globally and provide an overview of issues shaping the future of coal in the 21st century
Local decision makers’ awareness of the social determinants of health in Turkey: a cross-sectional study
The development and psychometric properties of the Arabic version of the child oral health impact profile-short form (COHIP- SF 19)
BACKGROUND: This study aims to cross-culturally adapt the original English-language COHIP-SF 19 to Arabic culture and to test its psychometric properties in a community sample. METHODS: The Arabic COHIP-SF 19 was developed and its psychometric properties were examined in a population-based sample of 876 schoolchildren who were aged 12 years of age, in Benghazi, Libya. The Arabic COHIP-SF 19 was tested for its internal consistency, reproducibility, construct validity, factorial validity and floor as well as ceiling effects. A Mann-Whitney U test was used to compare the mean scores of COHIP-SF 19 by participants' caries status and self-reported oral health rating, satisfaction and treatment need. RESULTS: The Arabic COHIP-SF 19 was successfully and smoothly developed. It showed an acceptable level of equivalence to the original version. Overall, the internal consistency and reproducibility were acceptable to excellent, with a Cronbach's alpha of 0.84 and an intra-class correlation coefficient (ICC) of 0.76. All hypotheses predefined to test construct validity were confirmed. That is, children who had active dental caries, and who rated their oral health as poor, were not satisfied with their oral health or indicated the need of treatment had lower COHIP-SF 19 scores (P < 0.05). Floor or ceiling effects were not observed. The exploratory Factorial analysis suggested a 4-component solution and deletion of one item. CONCLUSION: The Arabic COHIP-SF 19 was successfully developed. The measure demonstrated satisfactory reliability and validity to estimate OHRQoL in a representative sample of 12-year-old schoolchildren
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