151 resultados para Congo Fan


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In 2001 45% (2.7 billion) of the world’s population of approximately 6.1 billion lived in ‘moderate poverty’ on less than US $ 2 per person per day (World Population Summary, 2012). In the last 60 years there have been many theories attempting to explain development, why some countries have the fastest growth in history, while others stagnate and so far no way has been found to explain the differences. Traditional views imply that development is the aggregation of successes from multiple individual business enterprises, but this ignores the interactions between and among institutions, organisations and individuals in the economy, which can often have unpredictable effects. Complexity Development Theory proposes that by viewing development as an emergent property of society, we can help create better development programs at the organisational, institutional and national levels. This paper asks how the principals of CAS can be used to develop CDT principals used to develop and operate development programs at the bottom of the pyramid in developing economies. To investigate this research question we conduct a literature review to define and describe CDT and create propositions for testing. We illustrate these propositions using a case study of an Asset Based Community Development (ABCD) Program for existing and nascent entrepreneurs in the Democratic Republic of the Congo (DRC). We found evidence that all the principals of CDT were related to the characteristics of CAS. If this is the case, development programs will be able to select which CAS needed to test these propositions.

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Distributed computation and storage have been widely used for processing of big data sets. For many big data problems, with the size of data growing rapidly, the distribution of computing tasks and related data can affect the performance of the computing system greatly. In this paper, a distributed computing framework is presented for high performance computing of All-to-All Comparison Problems. A data distribution strategy is embedded in the framework for reduced storage space and balanced computing load. Experiments are conducted to demonstrate the effectiveness of the developed approach. They have shown that about 88% of the ideal performance capacity have be achieved in multiple machines through using the approach presented in this paper.

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Periodontitis is an inflammatory disease that causes osteolysis and tooth loss. It is known that the nuclear factor kappa B (NF-κB) signalling pathway plays a key role in the progression of inflammation and osteoclastogenesis in periodontitis. Parthenolide (PTL), a sesquiterpene lactone extracted from the shoots of Tanacetum parthenium, has been shown to possess anti-inflammatory properties in various diseases. In the study reported herein, we investigated the effects of PTL on the inflammatory and osteoclastogenic response of human periodontal ligament-derived cells (hPDLCs) and revealed the signalling pathways in this process. Our results showed that PTL decreased NF-κB activation, I-κB degradation, and ERK activation in hPDLCs. PTL significantly reduced the expression of inflammatory (IL-1β, IL-6, and TNF-α) and osteoclastogenic (RANKL, OPG, and M-CSF) genes in LPS-stimulated hPDLCs. In addition, PTL attenuated hPDLC-induced osteoclastogenic differentiation of macrophages (RAW264.7 cells), as well as reducing gene expression of osteoclast-related markers in RAW264.7 cells in an hPDLC-macrophage coculture model. Taken together, these results demonstrate the anti-inflammatory and antiosteoclastogenic activities of PTL in hPDLCs in vitro. These data offer fundamental evidence supporting the potential use of PTL in periodontitis treatment.

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The reliable response to weak biological signals requires that they be amplified with fidelity. In E. coli, the flagellar motors that control swimming can switch direction in response to very small changes in the concentration of the signaling protein CheY-P, but how this works is not well understood. A recently proposed allosteric model based on cooperative conformational spread in a ring of identical protomers seems promising as it is able to qualitatively reproduce switching, locked state behavior and Hill coefficient values measured for the rotary motor. In this paper we undertook a comprehensive simulation study to analyze the behavior of this model in detail and made predictions on three experimentally observable quantities: switch time distribution, locked state interval distribution, Hill coefficient of the switch response. We parameterized the model using experimental measurements, finding excellent agreement with published data on motor behavior. Analysis of the simulated switching dynamics revealed a mechanism for chemotactic ultrasensitivity, in which cooperativity is indispensable for realizing both coherent switching and effective amplification. These results showed how cells can combine elements of analog and digital control to produce switches that are simultaneously sensitive and reliable. © 2012 Ma et al.

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This book focuses on how evolutionary computing techniques benefit engineering research and development tasks by converting practical problems of growing complexities into simple formulations, thus largely reducing development efforts. This book begins with an overview of the optimization theory and modern evolutionary computing techniques, and goes on to cover specific applications of evolutionary computing to power system optimization and control problems.

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Parody accounts are prevalent on Twitter, offering irreverent interpretations of public figures, fictional characters and more. These accounts post comments framed within the context of their fictional universes or stereotypes of their subjects, responding in-character to topical events. This article positions parody accounts as a ritualised social media practice, an extension of fan practices and irreverent Internet culture. By providing a typology of parody accounts and analysing the topicality of selected parody accounts’ tweets, the research examines how these accounts contribute to topical discussions. In-character framing of topical comments allows parody accounts to offer original interpretations of breaking news that receive more attention than their other tweets. The presence and longevity of parody accounts underline the importance of humour on social media, including within news and topical coverage.

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Scarring is a significant medical burden; financially to the health care system and physically and psychologically for patients. Importantly, there have been numerous case reports describing the occurrence of cancer in burn scars. Currently available therapies are not satisfactory due to their undesirable side-effects, complex delivery routes, requirements for long-term use and/or expense. Radix Arnebiae (Zi Cao), a perennial herb, has been clinically applied to treat burns and manage scars for thousands of years in Asia. Shikonin, an active component extracted from Radix Arnebiae, has been demonstrated to induce apoptosis in cancer cells. Apoptosis is an essential process during scar tissue remodelling. It was therefore hypothesized that Shikonin may induce apoptosis in scar-associated cells. This investigation presents the first detailed in vitro study examining the functional responses of scar-associated cells to Shikonin, and investigates the mechanisms underlying these responses. The data obtained suggests that Shikonin inhibits cell viability and proliferation and reduces detectable collagen in scar-derived fibroblasts. Further investigation revealed that Shikonin induces apoptosis in scar fibroblasts by differentially regulating the expression of caspase 3, Bcl-2, phospho-Erk1/2 and phospho-p38. In addition, Shikonin down-regulates the expression of collagen I, collagen III and alpha-smooth muscle actin genes hence attenuating collagen synthesis in scar-derived fibroblasts. In summary, it is demonstrated that Shikonin induces apoptosis and decreases collagen production in scar-associated fibroblasts and may therefore hold potential as a novel scar remediation therapy.

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Power line inspection is a vital function for electricity supply companies but it involves labor-intensive and expensive procedures which are tedious and error-prone for humans to perform. A possible solution is to use an unmanned aerial vehicle (UAV) equipped with video surveillance equipment to perform the inspection. This paper considers how a small, electrically driven rotorcraft conceived for this application could be controlled by visually tracking the overhead supply lines. A dynamic model for a ducted-fan rotorcraft is presented and used to control the action of an Air Vehicle Simulator (AVS), consisting of a cable-array robot. Results show how visual data can be used to determine, and hence regulate in closed loop, the simulated vehicle’s position relative to the overhead lines.

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Background Little is known about the relation between vitamin D status in early life and neurodevelopment outcomes. Objective This study was designed to examine the association of cord blood 25-hydroxyvitamin D [25(OH)D] at birth with neurocognitive development in toddlers. Methods As part of the China-Anhui Birth Cohort Study, 363 mother-infant pairs with completed data were selected. Concentrations of 25(OH)D in cord blood were measured by radioimmunoassay. Mental development index (MDI) and psychomotor development index (PDI) in toddlers were assessed at age 16–18 mo by using the Bayley Scales of Infant Development. The data on maternal sociodemographic characteristics and other confounding factors were also prospectively collected. Results Toddlers in the lowest quintile of cord blood 25(OH)D exhibited a deficit of 7.60 (95% CI: −12.4, −2.82; P = 0.002) and 8.04 (95% CI: −12.9, −3.11; P = 0.001) points in the MDI and PDI scores, respectively, compared with the reference category. Unexpectedly, toddlers in the highest quintile of cord blood 25(OH)D also had a significant deficit of 12.3 (95% CI: −17.9, −6.67; P < 0.001) points in PDI scores compared with the reference category. Conclusions This prospective study suggested that there was an inverted-U–shaped relation between neonatal vitamin D status and neurocognitive development in toddlers. Additional studies on the optimal 25(OH)D concentrations in early life are needed.

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Objective High utilisation of emergency department (ED) among the elderly is of worldwide concern. This study aims to review the effectiveness of interventions targeting the elderly population in reducing ED utilisation. Methods Major biomedical databases were searched for relevant studies. Qualitative approach was applied to derive common themes in the myriad interventions and to critically assess the variations influencing interventions’ effectiveness. Quality of studies was appraised using the Effective Public Health Practice Project (EPPHP) tool. Results 36 studies were included. Nine of 16 community-based interventions reported significant reductions in ED utilisation. Five of 20 hospital-based interventions proved effective while another four demonstrated failure. Seven key elements were identified. Ten of 14 interventions associated with significant reduction on ED use integrated at least three of the seven elements. All four interventions with significant negative results lacked five or more of the seven elements. Some key elements including multidisciplinary team, integrated primary care and social care often existed in effective interventions, while were absent in all significantly ineffective ones. Conclusions The investigated interventions have mixed effectiveness. Our findings suggest the hospital-based interventions have relatively poorer effects, and should be better connected to the community-based strategies. Interventions seem to achieve the most success with integration of multi-layered elements, especially when incorporating key elements such as a nurse-led multidisciplinary team, integrated social care, and strong linkages to the longer-term primary and community care. Notwithstanding limitations in generalising the findings, this review builds on the growing body of evidence in this particular area.

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In a three day trial in April 2008, the United States District Court for the Southern District of New York considered whether the Harry Potter Lexicon infringed the intellectual property rights of J.K. Rowling and Warner Brothers. The case has attracted great media attention. As John Crace, a reporter for The Guardian, observed: “On one side: global-celebrity author J.K. Rowling. On the other: an amateur fan site devoted to the world's favourite boy wizard. At stake: the soul of Harry Potter.” J.K. Rowling is the author of the seven book Harry Potter series, which tell the story of a young wizard, Harry Potter, and his battles with Voldemort, the Lord of Darkness. As the court papers noted, “The Harry Potter Books are a modern day publishing phenomenon and success story.” Warner Brothers sought and obtained the film rights to the series. The entertainment company has thus far produced five films; a sixth is due in November 2008; and the final instalment is planned. The Harry Potter Lexicon is a reference guide created by Steven Vander Ark, a former grade school teacher. He has organised a large volume of material on the Harry Potter books and the Harry Potter films on a website in an alphabetical listing, from “A-Z”. The founder of RDR Books, Roger Rapoport, approached Ark to publish the Harry Potter Lexicon in a book form. Ark agreed to this request, and provided the publisher with a condensed version of the web-site. After RDR Books announced its intention to publish the reference book, J.K. Rowling and Warner Brothers brought a legal action in the United States District Court for the Southern District of New York, alleging that the publishers of the Harry Potter Lexicon were in breach of various intellectual property rights. A spokesperson for Warner Brothers and J.K. Rowling observed: "A fan’s affectionate enthusiasm should not obscure acts of plagiarism. The publishers knew what they were doing. The problem remains that the Lexicon takes an enormous amount of Ms. Rowling’s work and adds virtually no original commentary of its own. As we’ve said in court, it takes too much and adds too little. Authors have a duty to prevent the exploitation of their works by people who contribute nothing original, creative or interpretive." The litigation involves the intersection of copyright law, trade mark law, and consumer protection law. It has a wider significance because it deals with the protection of authorial rights; the use of literary indexes, supplements and reference guides; and the clash between character merchandising and fan fiction.

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Distributed systems are widely used for solving large-scale and data-intensive computing problems, including all-to-all comparison (ATAC) problems. However, when used for ATAC problems, existing computational frameworks such as Hadoop focus on load balancing for allocating comparison tasks, without careful consideration of data distribution and storage usage. While Hadoop-based solutions provide users with simplicity of implementation, their inherent MapReduce computing pattern does not match the ATAC pattern. This leads to load imbalances and poor data locality when Hadoop's data distribution strategy is used for ATAC problems. Here we present a data distribution strategy which considers data locality, load balancing and storage savings for ATAC computing problems in homogeneous distributed systems. A simulated annealing algorithm is developed for data distribution and task scheduling. Experimental results show a significant performance improvement for our approach over Hadoop-based solutions.

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The requirement of distributed computing of all-to-all comparison (ATAC) problems in heterogeneous systems is increasingly important in various domains. Though Hadoop-based solutions are widely used, they are inefficient for the ATAC pattern, which is fundamentally different from the MapReduce pattern for which Hadoop is designed. They exhibit poor data locality and unbalanced allocation of comparison tasks, particularly in heterogeneous systems. The results in massive data movement at runtime and ineffective utilization of computing resources, affecting the overall computing performance significantly. To address these problems, a scalable and efficient data and task distribution strategy is presented in this paper for processing large-scale ATAC problems in heterogeneous systems. It not only saves storage space but also achieves load balancing and good data locality for all comparison tasks. Experiments of bioinformatics examples show that about 89\% of the ideal performance capacity of the multiple machines have be achieved through using the approach presented in this paper.