210 research outputs found
An Experimental Study on the Heat Enhancement and the Bio-Heat Transfer Using Gold Macro Road and Ultrasound: A Potential Alternative to Kill Cancer Cells
We have previously proposed a method of treating solid tumors with a combination of gold macro-rods irradiated with ultrasound. Macro particle sized rods offer a greater circumferential treatment area over nanoparticle options. Experimental studies were conducted to investigate the heat enhancement and the bio-heat transfer to breast chicken using gold macro rod and ultrasound. An ultrasound, other than a focused ultrasound, may produce heat enough to cook a chicken breast up to about 1 cm diameter if a single gold rod is placed on the superficial tissue. Simulations and experimental results will provide the means to evaluate the treatment, to better design a patient-specific therapy to achieve maximum destruction of tumor and injury minimization of healthy tissue by controlling size, shape and location of gold seeds and ultrasound parameters
Ecological implications of a flower size/number trade-off in tropical forest trees
Peer reviewedPublisher PD
Y-chromosome descent clusters and male differential reproductive success: young lineage expansions dominate Asian pastoral nomadic populations
International audienceHigh-frequency microsatellite haplotypes of the male-specific Y-chromosome can signal past episodes of high reproductive success of particular men and their patrilineal descendants. Previously, two examples of such successful Y-lineages have been described in Asia, both associated with Altaic-speaking pastoral nomadic societies, and putatively linked to dynasties descending, respectively, from Genghis Khan and Giocangga. Here we surveyed a total of 5321 Y-chromosomes from 127 Asian populations, including novel Y-SNP and microsatellite data on 461 Central Asian males, to ask whether additional lineage expansions could be identified. Based on the most frequent eight-microsatellite haplotypes, we objectively defined 11 descent clusters (DCs), each within a specific haplogroup, that represent likely past instances of high male reproductive success, including the two previously identified cases. Analysis of the geographical patterns and ages of these DCs and their associated cultural characteristics showed that the most successful lineages are found both among sedentary agriculturalists and pastoral nomads, and expanded between 2100 BCE and 1100 CE. However, those with recent origins in the historical period are almost exclusively found in Altaic-speaking pastoral nomadic populations, which may reflect a shift in political organisation in pastoralist economies and a greater ease of transmission of Y-chromosomes through time and space facilitated by the use of horses
Решение оптимизационных задач для систем массового обслуживання с отказами в условиях неопределенности
Построены математические модели расчета показателей качества функционирования вычислительных
сетей, которые можно представить в виде сетей массового обслуживания с отказами. Сформулированы
задачи оптимизации показателей качества функционирования таких сетей при заданных ограничениях
на максимальную пропускную способность каналов связи и на выделяемые для модернизации сети ресурсы. Построены алгоритмы, которые позволяют решать поставленные оптимизационные задачи в
рамках оговоренных ограничений
The Barcode of Life Data Portal: Bridging the Biodiversity Informatics Divide for DNA Barcoding
With the volume of molecular sequence data that is systematically being generated globally, there is a need for centralized resources for data exploration and analytics. DNA Barcode initiatives are on track to generate a compendium of molecular sequence–based signatures for identifying animals and plants. To date, the range of available data exploration and analytic tools to explore these data have only been available in a boutique form—often representing a frustrating hurdle for many researchers that may not necessarily have resources to install or implement algorithms described by the analytic community. The Barcode of Life Data Portal (BDP) is a first step towards integrating the latest biodiversity informatics innovations with molecular sequence data from DNA barcoding. Through establishment of community driven standards, based on discussion with the Data Analysis Working Group (DAWG) of the Consortium for the Barcode of Life (CBOL), the BDP provides an infrastructure for incorporation of existing and next-generation DNA barcode analytic applications in an open forum
Enhanced response of the fricke solution doped with hematoporphyrin under X-rays irradiation
Developing inclusive pedagogies in HE through an understanding of the learner-consumer : promiscuity, hybridisation, and innovation
Abstract: This article contributes to debates about how to respond to the changing profile of Higher Education (HE) students, and the marketisation of HE, by challenging prevailing views about student engagement, in order to develop learner-centric and inclusive pedagogies which are relevant to the twenty-first century. The concepts of ‘participatory culture’ and ‘co-creativity’ are often associated with the digital world in which the current generation of students have grown up. But it is a mistake to assume that some learning styles are inherently more participatory than others: participation is not an effect of the medium or form, (analog vs digital), or the space (actual vs virtual), or the mode of interaction a (face-to-face vs networked) through which the learner participates – it is an effect of the practices involved. Students engage with a complex network of both digital and analog texts and spaces, and it is this postdigital hybrid setting within which student engagement takes place. Marketisation provides an opportunity to actively demonstrate our commitments to student-centredness and inclusive practice, by transcending the binary opposition between ‘Student as Partner’ and ‘Student as Consumer’ and recognizing that students are learner-consumers, and allowing students’ diversity to drive innovation, rather than continuing to disempower students by bolstering practices which privilege some learning styles above others, informed by the assumption that innovation is technology-led
Invasive Predators Deplete Genetic Diversity of Island Lizards
Invasive species can dramatically impact natural populations, especially those living on islands. Though numerous examples illustrate the ecological impact of invasive predators, no study has examined the genetic consequences for native populations subject to invasion. Here we capitalize on a natural experiment in which a long-term study of the brown anole lizard (Anolis sagrei) was interrupted by rat invasion. An island population that was devastated by rats recovered numerically following rat extermination. However, population genetic analyses at six microsatellite loci suggested a possible loss of genetic diversity due to invasion when compared to an uninvaded island studied over the same time frame. Our results provide partial support for the hypothesis that invasive predators can impact the genetic diversity of resident island populations
Fine-Scale Genetic Structure Arises during Range Expansion of an Invasive Gecko
Processes of range expansion are increasingly important in light of current concerns about invasive species and range shifts due to climate change. Theoretical studies suggest that genetic structuring may occur during range expansion. Ephemeral genetic structure can have important evolutionary implications, such as propagating genetic changes along the wave front of expansion, yet few studies have shown evidence of such structure. We tested the hypothesis that genetic structure arises during range expansion in Hemidactylus mabouia, a nocturnal African gecko recently introduced to Florida, USA. Twelve highly variable microsatellite loci were used to screen 418 individuals collected from 43 locations from four sampling sites across Florida, representing a gradient from earlier (∼1990s) to very recent colonization. We found earlier colonized locations had little detectable genetic structure and higher allelic richness than more recently colonized locations. Genetic structuring was pronounced among locations at spatial scales of tens to hundreds of meters near the leading edge of range expansion. Despite the rapid pace of range expansion in this introduced gecko, dispersal is limited among many suitable habitat patches. Fine-scale genetic structure is likely the result of founder effects during colonization of suitable habitat patches. It may be obscured over time and by scale-dependent modes of dispersal. Further studies are needed to determine if such genetic structure affects adaptation and trait evolution in range expansions and range shifts
Effective Long-Distance Pollen Dispersal in Centaurea jacea
BACKGROUND: Agri-environment schemes play an increasingly important role for the conservation of rare plants in intensively managed agricultural landscapes. However, little is known about their effects on gene flow via pollen dispersal between populations of these species. METHODOLOGY/PRINCIPAL FINDINGS: In a 2-year experiment, we observed effective pollen dispersal from source populations of Centaurea jacea in restored meadows, the most widespread Swiss agri-environment scheme, to potted plants in adjacent intensively managed meadows without other individuals of this species. Potted plants were put in replicated source populations at 25, 50, 100 m and where possible 200 m distance from these source populations. Pollen transfer among isolated plants was prevented by temporary bagging, such that only one isolated plant was accessible for flower visitors at any one time. Because C. jacea is self-incompatible, seed set in single-plant isolates indicated insect mediated effective pollen dispersal from the source population. Seed set was higher in source populations (35.7+/-4.4) than in isolates (4.8+/-1.0). Seed set declined from 18.9% of that in source populations at a distance of 25 m to 7.4% at 200 m. At a distance of 200 m seed set was still significantly higher in selfed plants, indicating long-distance effective pollen dispersal up to 200 m. Analyses of covariance suggested that bees contributed more than flies to this long-distance pollen dispersal. We found evidence that pollen dispersal to single-plant isolates was positively affected by the diversity and flower abundance of neighboring plant species in the intensively managed meadow. Furthermore, the decline of the dispersal was less steep when the source population of C. jacea was large. CONCLUSIONS: We conclude that insect pollinators can effectively transfer pollen from source populations of C. jacea over at least 200 m, even when "recipient populations" consisted of single-plant isolates, suggesting that gene flow by pollen over this distance is very likely. Source population size and flowering environment surrounding recipient plants appear to be important factors affecting pollen dispersal in C. jacea. It is conceivable that most insect-pollinated plants in a network of restored sites within intensively managed grassland can form metapopulations, if distances between sites are of similar magnitude as tested here
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