981 resultados para MiSeq paired-end technology
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The Brazilian Environmental Data Collecting System (SBCDA) collects and broadcasts meteorological and environmental data, to be handled by dozens of institutions and organizations. The system space segment, composed by the data collecting satellites, plays an important role for the system operation. To ensure the continuity and quality of these services, efforts are being made to the development of new satellite architectures. Aiming a reduction of size and power consumption, the design of an integrated circuit containing a receiver front-end is proposed, to be embedded in the next SBCDA satellite generations. The circuit will also operate under the requirements of the international data collecting standard ARGOS. This work focuses on the design of an UHF low noise amplifier and mixers in a CMOS standard technology. The specifi- cations are firstly described and the circuit topologies presented. Then the circuit conception is discussed and the design variables derived. Finally, the layout is designed and the final results are commented. The chip will be fabricated in a 130 nm technology from ST Microelectronics.
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Funding This work was supported by the HADEEP projects, funded by the Nippon Foundation, Japan (2009765188), the Natural Environmental Research Council, UK (NE/E007171/1) and the Total Foundation, France. We acknowledge additional support from the Marine Alliance for Science and Technology for Scotland (MASTS) funded by the Scottish Funding Council (Ref: HR09011) and contributing institutions. We also acknowledge support from the Leverhulme Trust to SBP. Additional sea time was supported by NIWA’s ‘Impact of Resource Use on Vulnerable Deep-Sea Communities’ project (CO1_0906)
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This report is a review of additive and subtractive manufacturing techniques. This approach (additive manufacturing) has resided largely in the prototyping realm, where the methods of producing complex freeform solid objects directly from a computer model without part-specific tooling or knowledge. But these technologies are evolving steadily and are beginning to encompass related systems of material addition, subtraction, assembly, and insertion of components made by other processes. Furthermore, these various additive processes are starting to evolve into rapid manufacturing techniques for mass-customized products, away from narrowly defined rapid prototyping. Taking this idea far enough down the line, and several years hence, a radical restructuring of manufacturing could take place. Manufacturing itself would move from a resource base to a knowledge base and from mass production of single use products to mass customized, high value, life cycle products, majority of research and development was focused on advanced development of existing technologies by improving processing performance, materials, modelling and simulation tools, and design tools to enable the transition from prototyping to manufacturing of end use parts.
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Biofouling, the accumulation of biomolecules, cells, organisms and their deposits on submerged and implanted surfaces, is a ubiquitous problem across various human endeavors including maritime operations, medicine, food industries and biotechnology. Since several decades, there have been substantial research efforts towards developing various types of antifouling and fouling release approaches to control bioaccumulation on man-made surfaces. In this work we hypothesized, investigated and developed dynamic change of the surface area and topology of elastomers as a general approach for biofouling management. Further, we combined dynamic surface deformation of elastomers with other existing antifouling and fouling-release approaches to develop multifunctional, pro-active biofouling control strategies.
This research work was focused on developing fundamental, new and environment-friendly approaches for biofouling management with emphasis on marine model systems and applications, but which also provided fundamental insights into the control of infectious biofilms on biomedical devices. We used different methods (mechanical stretching, electrical-actuation and pneumatic-actuation) to generate dynamic deformation of elastomer surfaces. Our initial studies showed that dynamic surface deformation methods are effective in detaching laboratory grown bacterial biofilms and barnacles. Further systematic studies revealed that a threshold critical surface strain is required to debond a biofilm from the surface, and this critical strain is dependent on the biofilm mechanical properties including adhesion energy, thickness and modulus. To test the dynamic surface deformation approach in natural environment, we conducted field studies (at Beaufort, NC) in natural seawater using pneumatic-actuation of silicone elastomer. The field studies also confirmed that a critical substrate strain is needed to detach natural biofilm accumulated in seawater. Additionally, the results from the field studies suggested that substrate modulus also affect the critical strain needed to debond biofilms. To sum up, both the laboratory and the field studies proved that dynamic surface deformation approach can effectively detach various biofilms and barnacles, and therefore offers a non-toxic and environmental friendly approach for biofouling management.
Deformable elastomer systems used in our studies are easy to fabricate and can be used as complementary approach for existing commercial strategies for biofouling control. To this end, we aimed towards developed proactive multifunctional surfaces and proposed two different approaches: (i) modification of elastomers with antifouling polymers to produce multifunctional, and (ii) incorporation of silicone-oil additives into the elastomer to enhance fouling-release performance.
In approach (i), we modified poly(vinylmethylsiloxane) elastomer surfaces with zwitterionic polymers using thiol-ene click chemistry and controlled free radical polymerization. These surfaces exhibited both fouling resistance and triggered fouling-release functionalities. The zwitterionic polymers exhibited fouling resistance over short-term (∼hours) exposure to bacteria and barnacle cyprids. The biofilms that eventually accumulated over prolonged-exposure (∼days) were easily detached by applying mechanical strain to the elastomer substrate. In approach (ii), we incorporated silicone-oil additives in deformable elastomer and studied synergistic effect of silicone-oils and surface strain on barnacle detachment. We hypothesized that incorporation of silicone-oil additive reduces the amount of surface strain needed to detach barnacles. Our experimental results supported the above hypothesis and suggested that surface-action of silicone-oils plays a major role in decreasing the strain needed to detach barnacles. Further, we also examined the effect of change in substrate modulus and showed that stiffer substrates require lower amount of strain to detach barnacles.
In summary, this study shows that (1) dynamic surface deformation can be used as an effective, environmental friendly approach for biofouling control (2) stretchable elastomer surfaces modified with anti-fouling polymers provides a pro-active, dual-mode approach for biofouling control, and (3) incorporation of silicone-oils additives into stretchable elastomers improves the fouling-release performance of dynamic surface deformation technology. Dynamic surface deformation by itself and as a supplementary approach can be utilized biofouling management in biomedical, industrial and marine applications.
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The interaction of reducing sugars, such as aldose, with proteins and the subsequent molecular rearrangements, produces irreversible advanced glycation end-products (AGEs), a heterogeneous class of non-enzymatic glycated proteins or lipids. AGEs form cross-links, trap macromolecules and release reactive oxygen intermediates. AGEs are linked to aging, and increase in several related diseases. The aim of this study was to assess, in a murine macrophage cell line, J774A.1, the effects of 48 h of exposure to glycated serum containing a known amount of pentosidine, a well-known AGE found in the plasma and tissues of diabetic and uremic subjects. Fetal bovine serum was incubated with ribose (50 mm) for 7 days at 37 °C to obtain about 10 nmol/ml of pentosidine. The cytotoxic parameters studied were cell morphology and viability by neutral red uptake, lactate dehydrogenase release and tetrazolium salt test. In the medium and in the intracellular compartment, bound and free pentosidine were evaluated by HPLC, as sensitive and specific glycative markers, and thiobarbituric acid reactive substances (TBARs), as index of the extent of lipid peroxidation. Our results confirm that macrophages are able to take up pentosidine. It is conceivable that bound pentosidine is degraded and free pentosidine is released inside the cell and then into the medium. The AGE increase in the medium was combined with an increase in TBARs, meaning that an oxidative stress occurred; marked cytotoxic effects were observed, and were followed by the release of free pentosidine and TBARs into the culture medium.
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Given recent demands for more co-creational university technology commercialisation
processes involving industry and end users, this paper adopts a micro level approach to explore
the challenges faced by universities when managing quadruple helix stakeholders within the
technology commercialisation processes. To explore this research question, a qualitative
research methodology which relies upon comparative case analysis was adopted to explore the
technology commercialisation process in two universities within a UK region. The findings
revealed that university type impacts Quadruple Helix stakeholder salience and engagement
and consequently university technology commercialisation activities and process. This is
important as recent European regional policy fails to account for contextual influences when
promoting Quadruple Helix stakeholder relationships in co-creational university technology
commercialisation.
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Thermal treatments and storage influence milk quality, particularly in low lactose milk as the higher concentration of reducing sugars can lead to the increased formation of the Maillard reaction products (MRPs). The control of the Amadori products (APs) formation is the key step to mitigate the Maillard reaction (MR) in milk. The use of fructosamine oxidases, (Faox) provided promising results. In this paper, the effects of Faox I were evaluated by monitoring the concentration of free and bound MRPs in low lactose milk during shelf life. Results showed that the enzyme reduced the formation of protein-bound MRPs down to 79% after six days at 37 °C. Faox I lowered the glycation of almost all the free amino acids resulting effective on basic and polar amino acids. Data here reported corroborate previous findings on the potentiality of Faox enzymes in controlling the early stage of the MR in foods.
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The present work investigates the fouling mechanisms of PVDF hollow fibre membrane (0.03 μm) during the dead end ultrafiltration at a fixed permeate flux (outside to inside configuration) of complex synthetic seawater composed by humic acids, alginic acids, inorganic particles and numerous salts at high concentrations. Short term ultrafiltration experiments at 100 L.h-1.m-2 show that the optimal specific filtered volume seems to be equal to 50 L.m-2. A residual fouling resistance equal to 2.1010 m-1 is added after each cycle of filtration during 8h of ultrafiltration at 100 L.h-1.m-2 and 50 L.m-2. Most of the fouling is reversible (80%). Organics are barely (15% of humic acids) retained by the membrane. Backwash efficiency drops during operation which induces less organics into backwash waters. Humic acids could preferentially accumulate on the membrane early in the ultrafiltration and alginic acids after the build-up of a fouling pre-layer. Colloids and particulates could accumulate inside a heterogeneous fouling layer and/or the concentrate compartment of the membrane module before being more largely recovered inside backwash waters.
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The author carries out a pedagogical reflection on how the technology driven distance learning repeatedly neglects the scientific achievements of Second Language Acquisition and Language Pedagogy. Seeing communicative competence as a major goal of a language classroom, she presents the main challenges that the communicative approach poses to distance learning. To this end, a general distance learning theory by Moore is adapted to the needs of language education, through a distinction between three aspects of learner interaction – with the teacher, with other learners and with content. In this three-dimensional paradigm the learner is seen as the main actor of the process, the teacher as a facilitator, the text as a main source of communicative data and the learner autonomy as the fundament of the process.
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With its powerful search engines and billions of published pages, the Worldwide Web has become the ultimate tool to explore the human experience. But, despite the advent of the digital revolution, e-books, at their core, have remained remarkably similar to their printed siblings. This has resulted in a clear dichotomy between two ways of reading: on one side, the multi-dimensional world of the Web; on the other, the linearity of books and e-books. My investigation of the literature indicates that the focus of attempts to merge these two modes of production, and hence of reading, has been the insertion of interactivity into fiction. As I will show in the Literature Review, a clear thrust of research since the early 1990s, and in my opinion the most significant, has concentrated on presenting the reader with choices that affect the plot. This has resulted in interactive stories in which the structure of the narrative can be altered by the reader of experimental fiction. The interest in this area of research is not surprising, as the interaction of readers with the fabric of the narrative provides a fertile ground for exploring, analysing, and discussing issues of plot consistency and continuity. I found in the literature several papers concerned with the effects of hyperlinking on literature, but none about how hyperlinked material and narrative could be integrated without compromising the narrative flow as designed by the author. It led me to think that the researchers had accepted hypertextuality and the linear organisation of fiction as being antithetical, thereby ignoring the possibility of exploiting the first while preserving the second. All the works I consulted were focussed on exploring the possibilities provided to authors (and readers) by hypertext or how hypertext literature affects literary criticism. This was true in earlier works by Landow and Harpold and remained true in later works by Bolter and Grusin. To quote another example, in his book Hypertext 3.0, Landow states: “Most who have speculated on the relation between hypertextuality and fiction concentrate [...] on the effects it will have on linear narrative”, and “hypertext opens major questions about story and plot by apparently doing away with linear organization” (Landow, 2006, pp. 220, 221). In other words, the authors have added narrative elements to Web pages, effectively placing their stories in a subordinate role. By focussing on “opening up” the plots, the researchers have missed the opportunity to maintain the integrity of their stories and use hyperlinked information to provide interactive access to backstory and factual bases. This would represent a missing link between the traditional way of reading, in which the readers have no influence on the path the author has laid out for them, and interactive narrative, in which the readers choose their way across alternatives, thereby, at least to a certain extent, creating their own path. It would be, to continue the metaphor, as if the readers could follow the main path created by the author while being able to get “sidetracked” into exploring hyperlinked material. In Hypertext 3.0, Landow refers to an “Axial structure [of hypertext] characteristic of electronic books and scholarly books with foot-and endnotes” versus a “Network structure of hypertext” (Landow, 2006, p. 70). My research aims at generalising the axial structure and extending it to fiction without losing the linearity at its core. In creative nonfiction, the introduction of places, scenes, and settings, together with characterisation, brings to life the facts without altering them; while much fiction draws on facts to provide a foundation, or narrative elements, for the work. But how can the reader distinguish between facts and representations? For example, to what extent do dialogues and perceptions present what was actually said and thought? Some authors of creative nonfiction use end-notes to provide comments and citations while minimising disruption the flow of the main text, but they are limited in scope and constrained in space. Each reader should be able to enjoy the narrative as if it were a novel but also to explore the facts at the level of detail s/he needs. For this to be possible, end-notes should provide a Web-like way of exploring in more detail what the author has already researched. My research aims to develop ways of integrating narrative prose and hyperlinked documents into a Hyperbook. Its goal is to create a new writing paradigm in which a story incorporates a gateway to detailed information. While creative nonfiction uses the techniques of fictional writing to provide reportage of actual events and fact-based fiction illuminates the affectual dimensions of what happened (e.g., Kate Grenville’s The Secret River and Hilary Mantel’s Wolf Hall), Hyperbooks go one step further and link narrative prose to the details of the events on which the narrative is based or, more in general, to information the reader might find of interest. My dissertation introduces and utilises Hyperbooks to engage in two parallel types of investigation Build knowledge about Italian WWII POWs held in Australia and present it as part of a novella in Hyperbook format. Develop a new piece of technology capable of extending the writing and reading process.
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Students with specific learning disabilities (SLD) typically learn less history content than their peers without disabilities and show fewer learning gains. Even when they are provided with the same instructional strategies, many students with SLD struggle to grasp complex historical concepts and content area vocabulary. Many strategies involving technology have been used in the past to enhance learning for students with SLD in history classrooms. However, very few studies have explored the effectiveness of emerging mobile technology in K-12 history classrooms. ^ This study investigated the effects of mobile devices (iPads) as an active student response (ASR) system on the acquisition of U.S. history content of middle school students with SLD. An alternating treatments single subject design was used to compare the effects of two interventions. There were two conditions and a series of pretest probesin this study. The conditions were: (a) direct instruction and studying from handwritten notes using the interactive notebook strategy and (b) direct instruction and studying using the Quizlet App on the iPad. There were three dependent variables in this study: (a) percent correct on tests, (b) rate of correct responses per minute, and (c) rate of errors per minute. ^ A comparative analysis suggested that both interventions (studying from interactive notes and studying using Quizlet on the iPad) had varying degrees of effectiveness in increasing the learning gains of students with SLD. In most cases, both interventions were equally effective. During both interventions, all of the participants increased their percentage correct and increased their rate of correct responses. Most of the participants decreased their rate of errors. ^ The results of this study suggest that teachers of students with SLD should consider a post lesson review in the form of mobile devices as an ASR system or studying from handwritten notes paired with existing evidence-based practices to facilitate students’ knowledge in U.S. history. Future research should focus on the use of other interactive applications on various mobile operating platforms, on other social studies subjects, and should explore various testing formats such as oral question-answer and multiple choice. ^
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The trend related to the turnover of internal combustion engine vehicles with EVs goes by the name of electrification. The push electrification experienced in the last decade is linked to the still ongoing evolution in power electronics technology for charging systems. This is the reason why an evolution in testing strategies and testing equipment is crucial too. The project this dissertation is based on concerns the investigation of a new EV simulator design. that optimizes the structure of the testing equipment used by the company who commissioned this work. Project requirements can be summarized in the following two points: space occupation reduction and parallel charging implementation. Some components were completely redesigned, and others were substituted with equivalent ones that could perform the same tasks. In this way it was possible to reduce the space occupation of the simulator, as well as to increase the efficiency of the testing device. Moreover, the possibility of conjugating different charging simulations could be investigated by parallelly launching two testing procedures on a unique machine, properly predisposed for supporting the two charging protocols used. On the back of the results achieved in the body of this dissertation, a new design for the EV simulator was proposed. In this way, space reduction was obtained, and space occupation efficiency was improved with the proposed new design. The testing device thus resulted to be way more compact, enabling to gain in safety and productivity, along with a 25% cost reduction. Furthermore, parallel charging was implemented in the proposed new design since the conducted tests clearly showed the feasibility of parallel charging sessions. The results presented in this work can thus be implemented to build the first prototype of the new EV simulator.