1,786 research outputs found
Learning from power system data stream: phasor-detective approach
Assuming access to synchronized stream of Phasor Measurement Unit (PMU) data
over a significant portion of a power system interconnect, say controlled by an
Independent System Operator (ISO), what can you extract about past, current and
future state of the system? We have focused on answering this practical
questions pragmatically - empowered with nothing but standard tools of data
analysis, such as PCA, filtering and cross-correlation analysis. Quite
surprisingly we have found that even during the quiet "no significant events"
period this standard set of statistical tools allows the "phasor-detective" to
extract from the data important hidden anomalies, such as problematic control
loops at loads and wind farms, and mildly malfunctioning assets, such as
transformers and generators. We also discuss and sketch future challenges a
mature phasor-detective can possibly tackle by adding machine learning and
physics modeling sophistication to the basic approach
Synthesis and Biological Evaluation of Chalcone Scaffolds as Potential Antiangiogenic Agents.
Angiogenesis is an integral part of tumour growth and development. Endothelial cell proliferation, migration and differentiation are the main hallmarks of this physiological process. From this, the use of antiangiogenic therapy have brought about a range of licensed FDA approved agents (that are also used by the NHS), that aim to regress tumour induced angiogenesis. However, issues such as: drug resistance, evasion and poor efficacy have limited the use of antiangiogenic therapy as a main stake in anti-cancer therapy. The need for multi-targeted or combinatorial therapies are ever more needed to enhance the current use of these drugs. Therefore, in an attempt to identify novel compounds that exhibit antiangiogenic activity, a group of 1-3-diphenylpropenones (chalcones) were designed, synthesised and biologically evaluated using AH1 (2-chloro-2’5’-dihydroxychalcone) as the parent compound. Methods: Chalcones were synthesised using variations of the Clasien-Schmidt condensation reaction, to develop a compound library based on AH1 (the parent compound). Thereafter, using HUVECs as an angiogenesis model, the effects of the compounds on HUVEC proliferation and migration were evaluated. This was carried out using the MTT cell proliferation assay and the wound healing “scratch” assay. Therein mechanistic evaluation was carried via gel electrophoresis and chemiluminescence western blot. Main findings: Structure activity relationships (SARs) studies identified, that novel compounds AH9 (2-bromo-2’5’-dihydroxychalcone) and AH12 (2-nitro-2’5’-dihydroxychalcone) were shown to exhibit strong anti-proliferative activity along with AH1. Other synthesised derivatives containing different functional groups such as, alkoxy, halogen and methyl did not exhibit similar activities to AH1. The culmination of structure activity relationship suggested that 2’5’-dihydroxy moiety was important to the observed activity only in conjunction with 2-chloro or now 2-bromo substitution on the other phenyl ring. Due to AH9’s better drug likeness over AH12, AH9 and AH1 were taken forward as the lead candidates. Anti-migratory analysis of lead candidates and licensed drug Sorafenib were conducted against HUVECs. AH9 (p < 0.0007) was shown to exhibit significantly more potent inhibitory effects on endothelial migration than AH1 (p = 0.19) and Sorafenib (p = 0.41) over the 8 hour time course study when compared to the untreated control. Mechanistic evaluation identified that AH9 could be exerting its anti-proliferative and potent anti-migratory activity via inhibiting ERK kinase phosphorylation, this was seen at 10μM (p < 0.0001). Discussion and conclusion: To summarise, anti-proliferative and potent anti-migratory activity, towards HUVECs, of a
novel molecule AH9 have been identified showing significant effects against two hallmarks of the angiogenesis cascade. AH9 presents a strong case as an agent capable of being developed as an angiogenesis inhibitor for anti-angiogenic therapy
Calcium Regulation of Single Ryanodine Receptor Channel Gating Analyzed Using HMM/MCMC Statistical Methods
Type-II ryanodine receptor channels (RYRs) play a fundamental role in intracellular Ca2+ dynamics in heart. The processes of activation, inactivation, and regulation of these channels have been the subject of intensive research and the focus of recent debates. Typically, approaches to understand these processes involve statistical analysis of single RYRs, involving signal restoration, model estimation, and selection. These tasks are usually performed by following rather phenomenological criteria that turn models into self-fulfilling prophecies. Here, a thorough statistical treatment is applied by modeling single RYRs using aggregated hidden Markov models. Inferences are made using Bayesian statistics and stochastic search methods known as Markov chain Monte Carlo. These methods allow extension of the temporal resolution of the analysis far beyond the limits of previous approaches and provide a direct measure of the uncertainties associated with every estimation step, together with a direct assessment of why and where a particular model fails. Analyses of single RYRs at several Ca2+ concentrations are made by considering 16 models, some of them previously reported in the literature. Results clearly show that single RYRs have Ca2+-dependent gating modes. Moreover, our results demonstrate that single RYRs responding to a sudden change in Ca2+ display adaptation kinetics. Interestingly, best ranked models predict microscopic reversibility when monovalent cations are used as the main permeating species. Finally, the extended bandwidth revealed the existence of novel fast buzz-mode at low Ca2+ concentrations
Strategically Enhancing Business Capabilities And Social Development In The Hispanic Community
Hurricane Katrina displaced more than one million people while destroying or badly disrupting more than 40% of Louisiana’s economic base. Thousands of small businesses ceased to exist. The socio-economic damage in the U.S. appears without precedent. The growing Hispanic population in southeast Louisiana presents a unique and distinctive socio-economic challenge. As Hispanics move into the region in large numbers seeking economic opportunities, specific needs are emerging. A variety of work and social skills must be developed and nurtured. Business skills and guidance must be offered. These needs must be recognized and addressed to facilitate a holistic assimilation of a growing Hispanic population into southeast Louisiana and develop a strong and literate workforce. The Hispanic Business Resources & Technology Center (HBRTC) was created by the Hispanic Chamber of Commerce of Louisiana (HCCL) in alliance with The Hispanic Apostolate Catholic Charities of the Archdiocese of New Orleans, The Jefferson Parish School System, and Southeastern Louisiana University, to address the post-Katrina crisis in the New Orleans region and to address needs of Hispanic families and businesses. The HBRTC is the first of its kind in the State of Louisiana to specifically address the myriad needs of the developing Hispanic workforce and community in Louisiana
Improving society by improving education through service-dominant logic: Reframing the role of students in higher education
The role of higher education (HE) in the development of societies is an unquestionable fact, and its management has traditionally been a major concern of governments. Lately, there has been worldwide debate on whether universities should adopt traditional management practices as applied in any business sector. This paper questions the adoption of these practices, because they tend to simplify the complexity of this service, and argues that service-dominant logic (SDL) is a more appropriate approach to manage HE institutions. It envisions HE as a complex system where many actors interact to co-create value and focuses on the student-teacher dyad. Through a critical literature review, this paper states that the increasing established analogy of the 'student-customer' and 'teacher-provider', adopted to simplify the complexity of the HE service and thus allow the implementation of traditional management practices, jeopardizes the sustainability of social development due to its effects on the long-term quality of professionals' training. Then, under the frame of SDL, we define students as co-creators of value (rather than customers) and teachers as value proposers, providing new insights to the debate and critical new recommendations for policymakers and universities to manage this critical relationship. © 2019 by the authors
Enhancing Multilingual Capability Among Hispanics
Hispanics are the country’s largest and fastest growing minority, but they are not an easily identified racial or ethnic group (Pew Hispanic Center, Trends 2005). In 2000, the U.S. Census reported 32.8 million Hispanics or Latinos in the United States, representing 12% of the total population. By 2004, the Hispanic population was estimated to have grown to over 40 million, an increase of more than 23% in just four years. The largest increase in the Hispanic population is occurring in the southern United States (Pew Hispanic Center). Paralleling the growth of the Hispanic population, the Hispanic labor force will expand to nearly 10 million by 2020 (Pew Hispanic Center). Language barriers and cultural sensitivities need to be addressed for optimal inclusion of this force in the U.S. The dramatic expansion of the Latino population in the State of Louisiana emphasizes the importance of this group, both socially and culturally. At the same time it presents new challenges and demands a real approach for addressing the languages barriers and the cultural sensitivities inherent in such a socioeconomic shift
OS ÍNDICES IGC, ENADE E CAPES NOS CURSOS DE ADMINISTRAÇÃO
Recentemente foi criado o Índice Geral de Curso (IGC) que avalia as instituições de uma maneira geral. Esse índice é gerado a partir de uma série de outros índices, bem como ENADE e CAPES. A utilização do índice poderá auxiliar gestores de IES e coordenadores de cursos como suporte para tomadas de decisão. Nesse sentido, o presente estudo teve como objetivo avaliar a similitude existente entre os índices de avaliação IGC, ENADE e CAPES dos cursos de administração. O curso de administração foi escolhido pela familiaridade dos autores com a área. A pesquisa desenvolvida foi de caráter exploratório, a partir de dados secundários que permitiram gerar uma tabela para 51 IES. A técnica estatística utilizada foi a Análise de Correspondência Múltipla. Os resultados demonstram que os cursos de administração corroboram com as notas altas do IGC. O destaque é para as regiões Sul e Sudeste, bem como para programas de pós-graduação em nível de mestrado, acadêmico e profissional, e doutorado, principalmente nas universidades federais. Conclui-se que este estudo poderá auxiliar gestores a refletir e relacionar o IGC com os cursos oferecidos de forma a buscar excelência, além de auxiliá-los a manter um mapeamento dos concorrentes
The AL-Gaussian Distribution as the Descriptive Model for the Internal Proactive Inhibition in the Standard Stop Signal Task
Measurements of response inhibition components of reactive inhibition and
proactive inhibition within the stop signal paradigm have been of special
interest for researchers since the 1980s. While frequentist nonparametric and
Bayesian parametric methods have been proposed to precisely estimate the entire
distribution of reactive inhibition, quantified by stop signal reaction
times(SSRT), there is no method yet in the stop-signal task literature to
precisely estimate the entire distribution of proactive inhibition. We
introduce an Asymmetric Laplace Gaussian (ALG) model to describe the
distribution of proactive inhibition. The proposed method is based on two
assumptions of independent trial type(go/stop) reaction times, and Ex-Gaussian
(ExG) models for them. Results indicated that the four parametric, ALG model
uniquely describes the proactive inhibition distribution and its key shape
features; and, its hazard function is monotonically increasing as are its three
parametric ExG components. In conclusion, both response inhibition components
can be uniquely modeled via variations of the four parametric ALG model
described with their associated similar distributional features.Comment: KEYWORDS Proactive Inhibition, Reaction Times, Ex-Gaussian,
Asymmetric Laplace Gaussian, Bayesian Parametric Approach, Hazard functio
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